1 /*
2  * Adaptec AIC7xxx device driver for Linux.
3  *
4  * $Id: //depot/aic7xxx/linux/drivers/scsi/aic7xxx/aic7xxx_osm.c#235 $
5  *
6  * Copyright (c) 1994 John Aycock
7  *   The University of Calgary Department of Computer Science.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2, or (at your option)
12  * any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; see the file COPYING.  If not, write to
21  * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Sources include the Adaptec 1740 driver (aha1740.c), the Ultrastor 24F
24  * driver (ultrastor.c), various Linux kernel source, the Adaptec EISA
25  * config file (!adp7771.cfg), the Adaptec AHA-2740A Series User's Guide,
26  * the Linux Kernel Hacker's Guide, Writing a SCSI Device Driver for Linux,
27  * the Adaptec 1542 driver (aha1542.c), the Adaptec EISA overlay file
28  * (adp7770.ovl), the Adaptec AHA-2740 Series Technical Reference Manual,
29  * the Adaptec AIC-7770 Data Book, the ANSI SCSI specification, the
30  * ANSI SCSI-2 specification (draft 10c), ...
31  *
32  * --------------------------------------------------------------------------
33  *
34  *  Modifications by Daniel M. Eischen (deischen@iworks.InterWorks.org):
35  *
36  *  Substantially modified to include support for wide and twin bus
37  *  adapters, DMAing of SCBs, tagged queueing, IRQ sharing, bug fixes,
38  *  SCB paging, and other rework of the code.
39  *
40  * --------------------------------------------------------------------------
41  * Copyright (c) 1994-2000 Justin T. Gibbs.
42  * Copyright (c) 2000-2001 Adaptec Inc.
43  * All rights reserved.
44  *
45  * Redistribution and use in source and binary forms, with or without
46  * modification, are permitted provided that the following conditions
47  * are met:
48  * 1. Redistributions of source code must retain the above copyright
49  *    notice, this list of conditions, and the following disclaimer,
50  *    without modification.
51  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
52  *    substantially similar to the "NO WARRANTY" disclaimer below
53  *    ("Disclaimer") and any redistribution must be conditioned upon
54  *    including a substantially similar Disclaimer requirement for further
55  *    binary redistribution.
56  * 3. Neither the names of the above-listed copyright holders nor the names
57  *    of any contributors may be used to endorse or promote products derived
58  *    from this software without specific prior written permission.
59  *
60  * Alternatively, this software may be distributed under the terms of the
61  * GNU General Public License ("GPL") version 2 as published by the Free
62  * Software Foundation.
63  *
64  * NO WARRANTY
65  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
66  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
67  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
68  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
69  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
70  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
71  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
72  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
73  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
74  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
75  * POSSIBILITY OF SUCH DAMAGES.
76  *
77  *---------------------------------------------------------------------------
78  *
79  *  Thanks also go to (in alphabetical order) the following:
80  *
81  *    Rory Bolt     - Sequencer bug fixes
82  *    Jay Estabrook - Initial DEC Alpha support
83  *    Doug Ledford  - Much needed abort/reset bug fixes
84  *    Kai Makisara  - DMAing of SCBs
85  *
86  *  A Boot time option was also added for not resetting the scsi bus.
87  *
88  *    Form:  aic7xxx=extended
89  *           aic7xxx=no_reset
90  *           aic7xxx=verbose
91  *
92  *  Daniel M. Eischen, deischen@iworks.InterWorks.org, 1/23/97
93  *
94  *  Id: aic7xxx.c,v 4.1 1997/06/12 08:23:42 deang Exp
95  */
96 
97 /*
98  * Further driver modifications made by Doug Ledford <dledford@redhat.com>
99  *
100  * Copyright (c) 1997-1999 Doug Ledford
101  *
102  * These changes are released under the same licensing terms as the FreeBSD
103  * driver written by Justin Gibbs.  Please see his Copyright notice above
104  * for the exact terms and conditions covering my changes as well as the
105  * warranty statement.
106  *
107  * Modifications made to the aic7xxx.c,v 4.1 driver from Dan Eischen include
108  * but are not limited to:
109  *
110  *  1: Import of the latest FreeBSD sequencer code for this driver
111  *  2: Modification of kernel code to accommodate different sequencer semantics
112  *  3: Extensive changes throughout kernel portion of driver to improve
113  *     abort/reset processing and error hanndling
114  *  4: Other work contributed by various people on the Internet
115  *  5: Changes to printk information and verbosity selection code
116  *  6: General reliability related changes, especially in IRQ management
117  *  7: Modifications to the default probe/attach order for supported cards
118  *  8: SMP friendliness has been improved
119  *
120  */
121 
122 #include "aic7xxx_osm.h"
123 #include "aic7xxx_inline.h"
124 #include <scsi/scsicam.h>
125 
126 /*
127  * Include aiclib.c as part of our
128  * "module dependencies are hard" work around.
129  */
130 #include "aiclib.c"
131 
132 #include <linux/init.h>		/* __setup */
133 
134 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
135 #include "sd.h"			/* For geometry detection */
136 #endif
137 
138 #include <linux/mm.h>		/* For fetching system memory size */
139 #include <linux/blkdev.h>		/* For block_size() */
140 #include <linux/delay.h>	/* For ssleep/msleep */
141 
142 /*
143  * Lock protecting manipulation of the ahc softc list.
144  */
145 spinlock_t ahc_list_spinlock;
146 
147 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
148 /* For dynamic sglist size calculation. */
149 u_int ahc_linux_nseg;
150 #endif
151 
152 /*
153  * Set this to the delay in seconds after SCSI bus reset.
154  * Note, we honor this only for the initial bus reset.
155  * The scsi error recovery code performs its own bus settle
156  * delay handling for error recovery actions.
157  */
158 #ifdef CONFIG_AIC7XXX_RESET_DELAY_MS
159 #define AIC7XXX_RESET_DELAY CONFIG_AIC7XXX_RESET_DELAY_MS
160 #else
161 #define AIC7XXX_RESET_DELAY 5000
162 #endif
163 
164 /*
165  * Control collection of SCSI transfer statistics for the /proc filesystem.
166  *
167  * NOTE: Do NOT enable this when running on kernels version 1.2.x and below.
168  * NOTE: This does affect performance since it has to maintain statistics.
169  */
170 #ifdef CONFIG_AIC7XXX_PROC_STATS
171 #define AIC7XXX_PROC_STATS
172 #endif
173 
174 /*
175  * To change the default number of tagged transactions allowed per-device,
176  * add a line to the lilo.conf file like:
177  * append="aic7xxx=verbose,tag_info:{{32,32,32,32},{32,32,32,32}}"
178  * which will result in the first four devices on the first two
179  * controllers being set to a tagged queue depth of 32.
180  *
181  * The tag_commands is an array of 16 to allow for wide and twin adapters.
182  * Twin adapters will use indexes 0-7 for channel 0, and indexes 8-15
183  * for channel 1.
184  */
185 typedef struct {
186 	uint8_t tag_commands[16];	/* Allow for wide/twin adapters. */
187 } adapter_tag_info_t;
188 
189 /*
190  * Modify this as you see fit for your system.
191  *
192  * 0			tagged queuing disabled
193  * 1 <= n <= 253	n == max tags ever dispatched.
194  *
195  * The driver will throttle the number of commands dispatched to a
196  * device if it returns queue full.  For devices with a fixed maximum
197  * queue depth, the driver will eventually determine this depth and
198  * lock it in (a console message is printed to indicate that a lock
199  * has occurred).  On some devices, queue full is returned for a temporary
200  * resource shortage.  These devices will return queue full at varying
201  * depths.  The driver will throttle back when the queue fulls occur and
202  * attempt to slowly increase the depth over time as the device recovers
203  * from the resource shortage.
204  *
205  * In this example, the first line will disable tagged queueing for all
206  * the devices on the first probed aic7xxx adapter.
207  *
208  * The second line enables tagged queueing with 4 commands/LUN for IDs
209  * (0, 2-11, 13-15), disables tagged queueing for ID 12, and tells the
210  * driver to attempt to use up to 64 tags for ID 1.
211  *
212  * The third line is the same as the first line.
213  *
214  * The fourth line disables tagged queueing for devices 0 and 3.  It
215  * enables tagged queueing for the other IDs, with 16 commands/LUN
216  * for IDs 1 and 4, 127 commands/LUN for ID 8, and 4 commands/LUN for
217  * IDs 2, 5-7, and 9-15.
218  */
219 
220 /*
221  * NOTE: The below structure is for reference only, the actual structure
222  *       to modify in order to change things is just below this comment block.
223 adapter_tag_info_t aic7xxx_tag_info[] =
224 {
225 	{{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
226 	{{4, 64, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0, 4, 4, 4}},
227 	{{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
228 	{{0, 16, 4, 0, 16, 4, 4, 4, 127, 4, 4, 4, 4, 4, 4, 4}}
229 };
230 */
231 
232 #ifdef CONFIG_AIC7XXX_CMDS_PER_DEVICE
233 #define AIC7XXX_CMDS_PER_DEVICE CONFIG_AIC7XXX_CMDS_PER_DEVICE
234 #else
235 #define AIC7XXX_CMDS_PER_DEVICE AHC_MAX_QUEUE
236 #endif
237 
238 #define AIC7XXX_CONFIGED_TAG_COMMANDS {					\
239 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
240 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
241 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
242 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
243 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
244 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
245 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
246 	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE		\
247 }
248 
249 /*
250  * By default, use the number of commands specified by
251  * the users kernel configuration.
252  */
253 static adapter_tag_info_t aic7xxx_tag_info[] =
254 {
255 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
256 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
257 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
258 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
259 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
260 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
261 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
262 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
263 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
264 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
265 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
266 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
267 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
268 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
269 	{AIC7XXX_CONFIGED_TAG_COMMANDS},
270 	{AIC7XXX_CONFIGED_TAG_COMMANDS}
271 };
272 
273 /*
274  * DV option:
275  *
276  * positive value = DV Enabled
277  * zero		  = DV Disabled
278  * negative value = DV Default for adapter type/seeprom
279  */
280 #ifdef CONFIG_AIC7XXX_DV_SETTING
281 #define AIC7XXX_CONFIGED_DV CONFIG_AIC7XXX_DV_SETTING
282 #else
283 #define AIC7XXX_CONFIGED_DV -1
284 #endif
285 
286 static int8_t aic7xxx_dv_settings[] =
287 {
288 	AIC7XXX_CONFIGED_DV,
289 	AIC7XXX_CONFIGED_DV,
290 	AIC7XXX_CONFIGED_DV,
291 	AIC7XXX_CONFIGED_DV,
292 	AIC7XXX_CONFIGED_DV,
293 	AIC7XXX_CONFIGED_DV,
294 	AIC7XXX_CONFIGED_DV,
295 	AIC7XXX_CONFIGED_DV,
296 	AIC7XXX_CONFIGED_DV,
297 	AIC7XXX_CONFIGED_DV,
298 	AIC7XXX_CONFIGED_DV,
299 	AIC7XXX_CONFIGED_DV,
300 	AIC7XXX_CONFIGED_DV,
301 	AIC7XXX_CONFIGED_DV,
302 	AIC7XXX_CONFIGED_DV,
303 	AIC7XXX_CONFIGED_DV
304 };
305 
306 /*
307  * There should be a specific return value for this in scsi.h, but
308  * it seems that most drivers ignore it.
309  */
310 #define DID_UNDERFLOW   DID_ERROR
311 
312 void
313 ahc_print_path(struct ahc_softc *ahc, struct scb *scb)
314 {
315 	printk("(scsi%d:%c:%d:%d): ",
316 	       ahc->platform_data->host->host_no,
317 	       scb != NULL ? SCB_GET_CHANNEL(ahc, scb) : 'X',
318 	       scb != NULL ? SCB_GET_TARGET(ahc, scb) : -1,
319 	       scb != NULL ? SCB_GET_LUN(scb) : -1);
320 }
321 
322 /*
323  * XXX - these options apply unilaterally to _all_ 274x/284x/294x
324  *       cards in the system.  This should be fixed.  Exceptions to this
325  *       rule are noted in the comments.
326  */
327 
328 /*
329  * Skip the scsi bus reset.  Non 0 make us skip the reset at startup.  This
330  * has no effect on any later resets that might occur due to things like
331  * SCSI bus timeouts.
332  */
333 static uint32_t aic7xxx_no_reset;
334 
335 /*
336  * Certain PCI motherboards will scan PCI devices from highest to lowest,
337  * others scan from lowest to highest, and they tend to do all kinds of
338  * strange things when they come into contact with PCI bridge chips.  The
339  * net result of all this is that the PCI card that is actually used to boot
340  * the machine is very hard to detect.  Most motherboards go from lowest
341  * PCI slot number to highest, and the first SCSI controller found is the
342  * one you boot from.  The only exceptions to this are when a controller
343  * has its BIOS disabled.  So, we by default sort all of our SCSI controllers
344  * from lowest PCI slot number to highest PCI slot number.  We also force
345  * all controllers with their BIOS disabled to the end of the list.  This
346  * works on *almost* all computers.  Where it doesn't work, we have this
347  * option.  Setting this option to non-0 will reverse the order of the sort
348  * to highest first, then lowest, but will still leave cards with their BIOS
349  * disabled at the very end.  That should fix everyone up unless there are
350  * really strange cirumstances.
351  */
352 static uint32_t aic7xxx_reverse_scan;
353 
354 /*
355  * Should we force EXTENDED translation on a controller.
356  *     0 == Use whatever is in the SEEPROM or default to off
357  *     1 == Use whatever is in the SEEPROM or default to on
358  */
359 static uint32_t aic7xxx_extended;
360 
361 /*
362  * PCI bus parity checking of the Adaptec controllers.  This is somewhat
363  * dubious at best.  To my knowledge, this option has never actually
364  * solved a PCI parity problem, but on certain machines with broken PCI
365  * chipset configurations where stray PCI transactions with bad parity are
366  * the norm rather than the exception, the error messages can be overwelming.
367  * It's included in the driver for completeness.
368  *   0	   = Shut off PCI parity check
369  *   non-0 = reverse polarity pci parity checking
370  */
371 static uint32_t aic7xxx_pci_parity = ~0;
372 
373 /*
374  * Certain newer motherboards have put new PCI based devices into the
375  * IO spaces that used to typically be occupied by VLB or EISA cards.
376  * This overlap can cause these newer motherboards to lock up when scanned
377  * for older EISA and VLB devices.  Setting this option to non-0 will
378  * cause the driver to skip scanning for any VLB or EISA controllers and
379  * only support the PCI controllers.  NOTE: this means that if the kernel
380  * os compiled with PCI support disabled, then setting this to non-0
381  * would result in never finding any devices :)
382  */
383 #ifndef CONFIG_AIC7XXX_PROBE_EISA_VL
384 uint32_t aic7xxx_probe_eisa_vl;
385 #else
386 uint32_t aic7xxx_probe_eisa_vl = ~0;
387 #endif
388 
389 /*
390  * There are lots of broken chipsets in the world.  Some of them will
391  * violate the PCI spec when we issue byte sized memory writes to our
392  * controller.  I/O mapped register access, if allowed by the given
393  * platform, will work in almost all cases.
394  */
395 uint32_t aic7xxx_allow_memio = ~0;
396 
397 /*
398  * aic7xxx_detect() has been run, so register all device arrivals
399  * immediately with the system rather than deferring to the sorted
400  * attachment performed by aic7xxx_detect().
401  */
402 int aic7xxx_detect_complete;
403 
404 /*
405  * So that we can set how long each device is given as a selection timeout.
406  * The table of values goes like this:
407  *   0 - 256ms
408  *   1 - 128ms
409  *   2 - 64ms
410  *   3 - 32ms
411  * We default to 256ms because some older devices need a longer time
412  * to respond to initial selection.
413  */
414 static uint32_t aic7xxx_seltime;
415 
416 /*
417  * Certain devices do not perform any aging on commands.  Should the
418  * device be saturated by commands in one portion of the disk, it is
419  * possible for transactions on far away sectors to never be serviced.
420  * To handle these devices, we can periodically send an ordered tag to
421  * force all outstanding transactions to be serviced prior to a new
422  * transaction.
423  */
424 uint32_t aic7xxx_periodic_otag;
425 
426 /*
427  * Module information and settable options.
428  */
429 static char *aic7xxx = NULL;
430 
431 MODULE_AUTHOR("Maintainer: Justin T. Gibbs <gibbs@scsiguy.com>");
432 MODULE_DESCRIPTION("Adaptec Aic77XX/78XX SCSI Host Bus Adapter driver");
433 MODULE_LICENSE("Dual BSD/GPL");
434 MODULE_VERSION(AIC7XXX_DRIVER_VERSION);
435 module_param(aic7xxx, charp, 0444);
436 MODULE_PARM_DESC(aic7xxx,
437 "period delimited, options string.\n"
438 "	verbose			Enable verbose/diagnostic logging\n"
439 "	allow_memio		Allow device registers to be memory mapped\n"
440 "	debug			Bitmask of debug values to enable\n"
441 "	no_probe		Toggle EISA/VLB controller probing\n"
442 "	probe_eisa_vl		Toggle EISA/VLB controller probing\n"
443 "	no_reset		Supress initial bus resets\n"
444 "	extended		Enable extended geometry on all controllers\n"
445 "	periodic_otag		Send an ordered tagged transaction\n"
446 "				periodically to prevent tag starvation.\n"
447 "				This may be required by some older disk\n"
448 "				drives or RAID arrays.\n"
449 "	reverse_scan		Sort PCI devices highest Bus/Slot to lowest\n"
450 "	tag_info:<tag_str>	Set per-target tag depth\n"
451 "	global_tag_depth:<int>	Global tag depth for every target\n"
452 "				on every bus\n"
453 "	dv:<dv_settings>	Set per-controller Domain Validation Setting.\n"
454 "	seltime:<int>		Selection Timeout\n"
455 "				(0/256ms,1/128ms,2/64ms,3/32ms)\n"
456 "\n"
457 "	Sample /etc/modprobe.conf line:\n"
458 "		Toggle EISA/VLB probing\n"
459 "		Set tag depth on Controller 1/Target 1 to 10 tags\n"
460 "		Shorten the selection timeout to 128ms\n"
461 "\n"
462 "	options aic7xxx 'aic7xxx=probe_eisa_vl.tag_info:{{}.{.10}}.seltime:1'\n"
463 );
464 
465 static void ahc_linux_handle_scsi_status(struct ahc_softc *,
466 					 struct ahc_linux_device *,
467 					 struct scb *);
468 static void ahc_linux_queue_cmd_complete(struct ahc_softc *ahc,
469 					 Scsi_Cmnd *cmd);
470 static void ahc_linux_filter_inquiry(struct ahc_softc*, struct ahc_devinfo*);
471 static void ahc_linux_sem_timeout(u_long arg);
472 static void ahc_linux_freeze_simq(struct ahc_softc *ahc);
473 static void ahc_linux_release_simq(u_long arg);
474 static void ahc_linux_dev_timed_unfreeze(u_long arg);
475 static int  ahc_linux_queue_recovery_cmd(Scsi_Cmnd *cmd, scb_flag flag);
476 static void ahc_linux_initialize_scsi_bus(struct ahc_softc *ahc);
477 static void ahc_linux_size_nseg(void);
478 static void ahc_linux_thread_run_complete_queue(struct ahc_softc *ahc);
479 static void ahc_linux_start_dv(struct ahc_softc *ahc);
480 static void ahc_linux_dv_timeout(struct scsi_cmnd *cmd);
481 static int  ahc_linux_dv_thread(void *data);
482 static void ahc_linux_kill_dv_thread(struct ahc_softc *ahc);
483 static void ahc_linux_dv_target(struct ahc_softc *ahc, u_int target);
484 static void ahc_linux_dv_transition(struct ahc_softc *ahc,
485 				    struct scsi_cmnd *cmd,
486 				    struct ahc_devinfo *devinfo,
487 				    struct ahc_linux_target *targ);
488 static void ahc_linux_dv_fill_cmd(struct ahc_softc *ahc,
489 				  struct scsi_cmnd *cmd,
490 				  struct ahc_devinfo *devinfo);
491 static void ahc_linux_dv_inq(struct ahc_softc *ahc,
492 			     struct scsi_cmnd *cmd,
493 			     struct ahc_devinfo *devinfo,
494 			     struct ahc_linux_target *targ,
495 			     u_int request_length);
496 static void ahc_linux_dv_tur(struct ahc_softc *ahc,
497 			     struct scsi_cmnd *cmd,
498 			     struct ahc_devinfo *devinfo);
499 static void ahc_linux_dv_rebd(struct ahc_softc *ahc,
500 			      struct scsi_cmnd *cmd,
501 			      struct ahc_devinfo *devinfo,
502 			      struct ahc_linux_target *targ);
503 static void ahc_linux_dv_web(struct ahc_softc *ahc,
504 			     struct scsi_cmnd *cmd,
505 			     struct ahc_devinfo *devinfo,
506 			     struct ahc_linux_target *targ);
507 static void ahc_linux_dv_reb(struct ahc_softc *ahc,
508 			     struct scsi_cmnd *cmd,
509 			     struct ahc_devinfo *devinfo,
510 			     struct ahc_linux_target *targ);
511 static void ahc_linux_dv_su(struct ahc_softc *ahc,
512 			    struct scsi_cmnd *cmd,
513 			    struct ahc_devinfo *devinfo,
514 			    struct ahc_linux_target *targ);
515 static int ahc_linux_fallback(struct ahc_softc *ahc,
516 			      struct ahc_devinfo *devinfo);
517 static void ahc_linux_dv_complete(Scsi_Cmnd *cmd);
518 static void ahc_linux_generate_dv_pattern(struct ahc_linux_target *targ);
519 static u_int ahc_linux_user_tagdepth(struct ahc_softc *ahc,
520 				     struct ahc_devinfo *devinfo);
521 static u_int ahc_linux_user_dv_setting(struct ahc_softc *ahc);
522 static void ahc_linux_device_queue_depth(struct ahc_softc *ahc,
523 					 struct ahc_linux_device *dev);
524 static struct ahc_linux_target*	ahc_linux_alloc_target(struct ahc_softc*,
525 						       u_int, u_int);
526 static void			ahc_linux_free_target(struct ahc_softc*,
527 						      struct ahc_linux_target*);
528 static struct ahc_linux_device*	ahc_linux_alloc_device(struct ahc_softc*,
529 						       struct ahc_linux_target*,
530 						       u_int);
531 static void			ahc_linux_free_device(struct ahc_softc*,
532 						      struct ahc_linux_device*);
533 static void ahc_linux_run_device_queue(struct ahc_softc*,
534 				       struct ahc_linux_device*);
535 static void ahc_linux_setup_tag_info_global(char *p);
536 static aic_option_callback_t ahc_linux_setup_tag_info;
537 static aic_option_callback_t ahc_linux_setup_dv;
538 static int  aic7xxx_setup(char *s);
539 static int  ahc_linux_next_unit(void);
540 static void ahc_runq_tasklet(unsigned long data);
541 static struct ahc_cmd *ahc_linux_run_complete_queue(struct ahc_softc *ahc);
542 
543 /********************************* Inlines ************************************/
544 static __inline void ahc_schedule_runq(struct ahc_softc *ahc);
545 static __inline struct ahc_linux_device*
546 		     ahc_linux_get_device(struct ahc_softc *ahc, u_int channel,
547 					  u_int target, u_int lun, int alloc);
548 static __inline void ahc_schedule_completeq(struct ahc_softc *ahc);
549 static __inline void ahc_linux_check_device_queue(struct ahc_softc *ahc,
550 						  struct ahc_linux_device *dev);
551 static __inline struct ahc_linux_device *
552 		     ahc_linux_next_device_to_run(struct ahc_softc *ahc);
553 static __inline void ahc_linux_run_device_queues(struct ahc_softc *ahc);
554 static __inline void ahc_linux_unmap_scb(struct ahc_softc*, struct scb*);
555 
556 static __inline int ahc_linux_map_seg(struct ahc_softc *ahc, struct scb *scb,
557 		 		      struct ahc_dma_seg *sg,
558 				      dma_addr_t addr, bus_size_t len);
559 
560 static __inline void
561 ahc_schedule_completeq(struct ahc_softc *ahc)
562 {
563 	if ((ahc->platform_data->flags & AHC_RUN_CMPLT_Q_TIMER) == 0) {
564 		ahc->platform_data->flags |= AHC_RUN_CMPLT_Q_TIMER;
565 		ahc->platform_data->completeq_timer.expires = jiffies;
566 		add_timer(&ahc->platform_data->completeq_timer);
567 	}
568 }
569 
570 /*
571  * Must be called with our lock held.
572  */
573 static __inline void
574 ahc_schedule_runq(struct ahc_softc *ahc)
575 {
576 	tasklet_schedule(&ahc->platform_data->runq_tasklet);
577 }
578 
579 static __inline struct ahc_linux_device*
580 ahc_linux_get_device(struct ahc_softc *ahc, u_int channel, u_int target,
581 		     u_int lun, int alloc)
582 {
583 	struct ahc_linux_target *targ;
584 	struct ahc_linux_device *dev;
585 	u_int target_offset;
586 
587 	target_offset = target;
588 	if (channel != 0)
589 		target_offset += 8;
590 	targ = ahc->platform_data->targets[target_offset];
591 	if (targ == NULL) {
592 		if (alloc != 0) {
593 			targ = ahc_linux_alloc_target(ahc, channel, target);
594 			if (targ == NULL)
595 				return (NULL);
596 		} else
597 			return (NULL);
598 	}
599 	dev = targ->devices[lun];
600 	if (dev == NULL && alloc != 0)
601 		dev = ahc_linux_alloc_device(ahc, targ, lun);
602 	return (dev);
603 }
604 
605 #define AHC_LINUX_MAX_RETURNED_ERRORS 4
606 static struct ahc_cmd *
607 ahc_linux_run_complete_queue(struct ahc_softc *ahc)
608 {
609 	struct	ahc_cmd *acmd;
610 	u_long	done_flags;
611 	int	with_errors;
612 
613 	with_errors = 0;
614 	ahc_done_lock(ahc, &done_flags);
615 	while ((acmd = TAILQ_FIRST(&ahc->platform_data->completeq)) != NULL) {
616 		Scsi_Cmnd *cmd;
617 
618 		if (with_errors > AHC_LINUX_MAX_RETURNED_ERRORS) {
619 			/*
620 			 * Linux uses stack recursion to requeue
621 			 * commands that need to be retried.  Avoid
622 			 * blowing out the stack by "spoon feeding"
623 			 * commands that completed with error back
624 			 * the operating system in case they are going
625 			 * to be retried. "ick"
626 			 */
627 			ahc_schedule_completeq(ahc);
628 			break;
629 		}
630 		TAILQ_REMOVE(&ahc->platform_data->completeq,
631 			     acmd, acmd_links.tqe);
632 		cmd = &acmd_scsi_cmd(acmd);
633 		cmd->host_scribble = NULL;
634 		if (ahc_cmd_get_transaction_status(cmd) != DID_OK
635 		 || (cmd->result & 0xFF) != SCSI_STATUS_OK)
636 			with_errors++;
637 
638 		cmd->scsi_done(cmd);
639 	}
640 	ahc_done_unlock(ahc, &done_flags);
641 	return (acmd);
642 }
643 
644 static __inline void
645 ahc_linux_check_device_queue(struct ahc_softc *ahc,
646 			     struct ahc_linux_device *dev)
647 {
648 	if ((dev->flags & AHC_DEV_FREEZE_TIL_EMPTY) != 0
649 	 && dev->active == 0) {
650 		dev->flags &= ~AHC_DEV_FREEZE_TIL_EMPTY;
651 		dev->qfrozen--;
652 	}
653 
654 	if (TAILQ_FIRST(&dev->busyq) == NULL
655 	 || dev->openings == 0 || dev->qfrozen != 0)
656 		return;
657 
658 	ahc_linux_run_device_queue(ahc, dev);
659 }
660 
661 static __inline struct ahc_linux_device *
662 ahc_linux_next_device_to_run(struct ahc_softc *ahc)
663 {
664 
665 	if ((ahc->flags & AHC_RESOURCE_SHORTAGE) != 0
666 	 || (ahc->platform_data->qfrozen != 0
667 	  && AHC_DV_SIMQ_FROZEN(ahc) == 0))
668 		return (NULL);
669 	return (TAILQ_FIRST(&ahc->platform_data->device_runq));
670 }
671 
672 static __inline void
673 ahc_linux_run_device_queues(struct ahc_softc *ahc)
674 {
675 	struct ahc_linux_device *dev;
676 
677 	while ((dev = ahc_linux_next_device_to_run(ahc)) != NULL) {
678 		TAILQ_REMOVE(&ahc->platform_data->device_runq, dev, links);
679 		dev->flags &= ~AHC_DEV_ON_RUN_LIST;
680 		ahc_linux_check_device_queue(ahc, dev);
681 	}
682 }
683 
684 static __inline void
685 ahc_linux_unmap_scb(struct ahc_softc *ahc, struct scb *scb)
686 {
687 	Scsi_Cmnd *cmd;
688 
689 	cmd = scb->io_ctx;
690 	ahc_sync_sglist(ahc, scb, BUS_DMASYNC_POSTWRITE);
691 	if (cmd->use_sg != 0) {
692 		struct scatterlist *sg;
693 
694 		sg = (struct scatterlist *)cmd->request_buffer;
695 		pci_unmap_sg(ahc->dev_softc, sg, cmd->use_sg,
696 			     scsi_to_pci_dma_dir(cmd->sc_data_direction));
697 	} else if (cmd->request_bufflen != 0) {
698 		pci_unmap_single(ahc->dev_softc,
699 				 scb->platform_data->buf_busaddr,
700 				 cmd->request_bufflen,
701 				 scsi_to_pci_dma_dir(cmd->sc_data_direction));
702 	}
703 }
704 
705 static __inline int
706 ahc_linux_map_seg(struct ahc_softc *ahc, struct scb *scb,
707 		  struct ahc_dma_seg *sg, dma_addr_t addr, bus_size_t len)
708 {
709 	int	 consumed;
710 
711 	if ((scb->sg_count + 1) > AHC_NSEG)
712 		panic("Too few segs for dma mapping.  "
713 		      "Increase AHC_NSEG\n");
714 
715 	consumed = 1;
716 	sg->addr = ahc_htole32(addr & 0xFFFFFFFF);
717 	scb->platform_data->xfer_len += len;
718 
719 	if (sizeof(dma_addr_t) > 4
720 	 && (ahc->flags & AHC_39BIT_ADDRESSING) != 0)
721 		len |= (addr >> 8) & AHC_SG_HIGH_ADDR_MASK;
722 
723 	sg->len = ahc_htole32(len);
724 	return (consumed);
725 }
726 
727 /************************  Host template entry points *************************/
728 static int	   ahc_linux_detect(Scsi_Host_Template *);
729 static int	   ahc_linux_queue(Scsi_Cmnd *, void (*)(Scsi_Cmnd *));
730 static const char *ahc_linux_info(struct Scsi_Host *);
731 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
732 static int	   ahc_linux_slave_alloc(Scsi_Device *);
733 static int	   ahc_linux_slave_configure(Scsi_Device *);
734 static void	   ahc_linux_slave_destroy(Scsi_Device *);
735 #if defined(__i386__)
736 static int	   ahc_linux_biosparam(struct scsi_device*,
737 				       struct block_device*,
738 				       sector_t, int[]);
739 #endif
740 #else
741 static int	   ahc_linux_release(struct Scsi_Host *);
742 static void	   ahc_linux_select_queue_depth(struct Scsi_Host *host,
743 						Scsi_Device *scsi_devs);
744 #if defined(__i386__)
745 static int	   ahc_linux_biosparam(Disk *, kdev_t, int[]);
746 #endif
747 #endif
748 static int	   ahc_linux_bus_reset(Scsi_Cmnd *);
749 static int	   ahc_linux_dev_reset(Scsi_Cmnd *);
750 static int	   ahc_linux_abort(Scsi_Cmnd *);
751 
752 /*
753  * Calculate a safe value for AHC_NSEG (as expressed through ahc_linux_nseg).
754  *
755  * In pre-2.5.X...
756  * The midlayer allocates an S/G array dynamically when a command is issued
757  * using SCSI malloc.  This array, which is in an OS dependent format that
758  * must later be copied to our private S/G list, is sized to house just the
759  * number of segments needed for the current transfer.  Since the code that
760  * sizes the SCSI malloc pool does not take into consideration fragmentation
761  * of the pool, executing transactions numbering just a fraction of our
762  * concurrent transaction limit with list lengths aproaching AHC_NSEG will
763  * quickly depleat the SCSI malloc pool of usable space.  Unfortunately, the
764  * mid-layer does not properly handle this scsi malloc failures for the S/G
765  * array and the result can be a lockup of the I/O subsystem.  We try to size
766  * our S/G list so that it satisfies our drivers allocation requirements in
767  * addition to avoiding fragmentation of the SCSI malloc pool.
768  */
769 static void
770 ahc_linux_size_nseg(void)
771 {
772 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
773 	u_int cur_size;
774 	u_int best_size;
775 
776 	/*
777 	 * The SCSI allocator rounds to the nearest 512 bytes
778 	 * an cannot allocate across a page boundary.  Our algorithm
779 	 * is to start at 1K of scsi malloc space per-command and
780 	 * loop through all factors of the PAGE_SIZE and pick the best.
781 	 */
782 	best_size = 0;
783 	for (cur_size = 1024; cur_size <= PAGE_SIZE; cur_size *= 2) {
784 		u_int nseg;
785 
786 		nseg = cur_size / sizeof(struct scatterlist);
787 		if (nseg < AHC_LINUX_MIN_NSEG)
788 			continue;
789 
790 		if (best_size == 0) {
791 			best_size = cur_size;
792 			ahc_linux_nseg = nseg;
793 		} else {
794 			u_int best_rem;
795 			u_int cur_rem;
796 
797 			/*
798 			 * Compare the traits of the current "best_size"
799 			 * with the current size to determine if the
800 			 * current size is a better size.
801 			 */
802 			best_rem = best_size % sizeof(struct scatterlist);
803 			cur_rem = cur_size % sizeof(struct scatterlist);
804 			if (cur_rem < best_rem) {
805 				best_size = cur_size;
806 				ahc_linux_nseg = nseg;
807 			}
808 		}
809 	}
810 #endif
811 }
812 
813 /*
814  * Try to detect an Adaptec 7XXX controller.
815  */
816 static int
817 ahc_linux_detect(Scsi_Host_Template *template)
818 {
819 	struct	ahc_softc *ahc;
820 	int     found = 0;
821 
822 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
823 	/*
824 	 * It is a bug that the upper layer takes
825 	 * this lock just prior to calling us.
826 	 */
827 	spin_unlock_irq(&io_request_lock);
828 #endif
829 
830 	/*
831 	 * Sanity checking of Linux SCSI data structures so
832 	 * that some of our hacks^H^H^H^H^Hassumptions aren't
833 	 * violated.
834 	 */
835 	if (offsetof(struct ahc_cmd_internal, end)
836 	  > offsetof(struct scsi_cmnd, host_scribble)) {
837 		printf("ahc_linux_detect: SCSI data structures changed.\n");
838 		printf("ahc_linux_detect: Unable to attach\n");
839 		return (0);
840 	}
841 	ahc_linux_size_nseg();
842 	/*
843 	 * If we've been passed any parameters, process them now.
844 	 */
845 	if (aic7xxx)
846 		aic7xxx_setup(aic7xxx);
847 
848 	template->proc_name = "aic7xxx";
849 
850 	/*
851 	 * Initialize our softc list lock prior to
852 	 * probing for any adapters.
853 	 */
854 	ahc_list_lockinit();
855 
856 	found = ahc_linux_pci_init();
857 	if (!ahc_linux_eisa_init())
858 		found++;
859 
860 	/*
861 	 * Register with the SCSI layer all
862 	 * controllers we've found.
863 	 */
864 	TAILQ_FOREACH(ahc, &ahc_tailq, links) {
865 
866 		if (ahc_linux_register_host(ahc, template) == 0)
867 			found++;
868 	}
869 
870 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
871 	spin_lock_irq(&io_request_lock);
872 #endif
873 	aic7xxx_detect_complete++;
874 
875 	return (found);
876 }
877 
878 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
879 /*
880  * Free the passed in Scsi_Host memory structures prior to unloading the
881  * module.
882  */
883 int
884 ahc_linux_release(struct Scsi_Host * host)
885 {
886 	struct ahc_softc *ahc;
887 	u_long l;
888 
889 	ahc_list_lock(&l);
890 	if (host != NULL) {
891 
892 		/*
893 		 * We should be able to just perform
894 		 * the free directly, but check our
895 		 * list for extra sanity.
896 		 */
897 		ahc = ahc_find_softc(*(struct ahc_softc **)host->hostdata);
898 		if (ahc != NULL) {
899 			u_long s;
900 
901 			ahc_lock(ahc, &s);
902 			ahc_intr_enable(ahc, FALSE);
903 			ahc_unlock(ahc, &s);
904 			ahc_free(ahc);
905 		}
906 	}
907 	ahc_list_unlock(&l);
908 	return (0);
909 }
910 #endif
911 
912 /*
913  * Return a string describing the driver.
914  */
915 static const char *
916 ahc_linux_info(struct Scsi_Host *host)
917 {
918 	static char buffer[512];
919 	char	ahc_info[256];
920 	char   *bp;
921 	struct ahc_softc *ahc;
922 
923 	bp = &buffer[0];
924 	ahc = *(struct ahc_softc **)host->hostdata;
925 	memset(bp, 0, sizeof(buffer));
926 	strcpy(bp, "Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA DRIVER, Rev ");
927 	strcat(bp, AIC7XXX_DRIVER_VERSION);
928 	strcat(bp, "\n");
929 	strcat(bp, "        <");
930 	strcat(bp, ahc->description);
931 	strcat(bp, ">\n");
932 	strcat(bp, "        ");
933 	ahc_controller_info(ahc, ahc_info);
934 	strcat(bp, ahc_info);
935 	strcat(bp, "\n");
936 
937 	return (bp);
938 }
939 
940 /*
941  * Queue an SCB to the controller.
942  */
943 static int
944 ahc_linux_queue(Scsi_Cmnd * cmd, void (*scsi_done) (Scsi_Cmnd *))
945 {
946 	struct	 ahc_softc *ahc;
947 	struct	 ahc_linux_device *dev;
948 	u_long	 flags;
949 
950 	ahc = *(struct ahc_softc **)cmd->device->host->hostdata;
951 
952 	/*
953 	 * Save the callback on completion function.
954 	 */
955 	cmd->scsi_done = scsi_done;
956 
957 	ahc_midlayer_entrypoint_lock(ahc, &flags);
958 
959 	/*
960 	 * Close the race of a command that was in the process of
961 	 * being queued to us just as our simq was frozen.  Let
962 	 * DV commands through so long as we are only frozen to
963 	 * perform DV.
964 	 */
965 	if (ahc->platform_data->qfrozen != 0
966 	 && AHC_DV_CMD(cmd) == 0) {
967 
968 		ahc_cmd_set_transaction_status(cmd, CAM_REQUEUE_REQ);
969 		ahc_linux_queue_cmd_complete(ahc, cmd);
970 		ahc_schedule_completeq(ahc);
971 		ahc_midlayer_entrypoint_unlock(ahc, &flags);
972 		return (0);
973 	}
974 	dev = ahc_linux_get_device(ahc, cmd->device->channel, cmd->device->id,
975 				   cmd->device->lun, /*alloc*/TRUE);
976 	if (dev == NULL) {
977 		ahc_cmd_set_transaction_status(cmd, CAM_RESRC_UNAVAIL);
978 		ahc_linux_queue_cmd_complete(ahc, cmd);
979 		ahc_schedule_completeq(ahc);
980 		ahc_midlayer_entrypoint_unlock(ahc, &flags);
981 		printf("%s: aic7xxx_linux_queue - Unable to allocate device!\n",
982 		       ahc_name(ahc));
983 		return (0);
984 	}
985 	cmd->result = CAM_REQ_INPROG << 16;
986 	TAILQ_INSERT_TAIL(&dev->busyq, (struct ahc_cmd *)cmd, acmd_links.tqe);
987 	if ((dev->flags & AHC_DEV_ON_RUN_LIST) == 0) {
988 		TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq, dev, links);
989 		dev->flags |= AHC_DEV_ON_RUN_LIST;
990 		ahc_linux_run_device_queues(ahc);
991 	}
992 	ahc_midlayer_entrypoint_unlock(ahc, &flags);
993 	return (0);
994 }
995 
996 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
997 static int
998 ahc_linux_slave_alloc(Scsi_Device *device)
999 {
1000 	struct	ahc_softc *ahc;
1001 
1002 	ahc = *((struct ahc_softc **)device->host->hostdata);
1003 	if (bootverbose)
1004 		printf("%s: Slave Alloc %d\n", ahc_name(ahc), device->id);
1005 	return (0);
1006 }
1007 
1008 static int
1009 ahc_linux_slave_configure(Scsi_Device *device)
1010 {
1011 	struct	ahc_softc *ahc;
1012 	struct	ahc_linux_device *dev;
1013 	u_long	flags;
1014 
1015 	ahc = *((struct ahc_softc **)device->host->hostdata);
1016 	if (bootverbose)
1017 		printf("%s: Slave Configure %d\n", ahc_name(ahc), device->id);
1018 	ahc_midlayer_entrypoint_lock(ahc, &flags);
1019 	/*
1020 	 * Since Linux has attached to the device, configure
1021 	 * it so we don't free and allocate the device
1022 	 * structure on every command.
1023 	 */
1024 	dev = ahc_linux_get_device(ahc, device->channel,
1025 				   device->id, device->lun,
1026 				   /*alloc*/TRUE);
1027 	if (dev != NULL) {
1028 		dev->flags &= ~AHC_DEV_UNCONFIGURED;
1029 		dev->scsi_device = device;
1030 		ahc_linux_device_queue_depth(ahc, dev);
1031 	}
1032 	ahc_midlayer_entrypoint_unlock(ahc, &flags);
1033 	return (0);
1034 }
1035 
1036 static void
1037 ahc_linux_slave_destroy(Scsi_Device *device)
1038 {
1039 	struct	ahc_softc *ahc;
1040 	struct	ahc_linux_device *dev;
1041 	u_long	flags;
1042 
1043 	ahc = *((struct ahc_softc **)device->host->hostdata);
1044 	if (bootverbose)
1045 		printf("%s: Slave Destroy %d\n", ahc_name(ahc), device->id);
1046 	ahc_midlayer_entrypoint_lock(ahc, &flags);
1047 	dev = ahc_linux_get_device(ahc, device->channel,
1048 				   device->id, device->lun,
1049 					   /*alloc*/FALSE);
1050 	/*
1051 	 * Filter out "silly" deletions of real devices by only
1052 	 * deleting devices that have had slave_configure()
1053 	 * called on them.  All other devices that have not
1054 	 * been configured will automatically be deleted by
1055 	 * the refcounting process.
1056 	 */
1057 	if (dev != NULL
1058 	 && (dev->flags & AHC_DEV_SLAVE_CONFIGURED) != 0) {
1059 		dev->flags |= AHC_DEV_UNCONFIGURED;
1060 		if (TAILQ_EMPTY(&dev->busyq)
1061 		 && dev->active == 0
1062 	 	 && (dev->flags & AHC_DEV_TIMER_ACTIVE) == 0)
1063 			ahc_linux_free_device(ahc, dev);
1064 	}
1065 	ahc_midlayer_entrypoint_unlock(ahc, &flags);
1066 }
1067 #else
1068 /*
1069  * Sets the queue depth for each SCSI device hanging
1070  * off the input host adapter.
1071  */
1072 static void
1073 ahc_linux_select_queue_depth(struct Scsi_Host *host, Scsi_Device *scsi_devs)
1074 {
1075 	Scsi_Device *device;
1076 	Scsi_Device *ldev;
1077 	struct	ahc_softc *ahc;
1078 	u_long	flags;
1079 
1080 	ahc = *((struct ahc_softc **)host->hostdata);
1081 	ahc_lock(ahc, &flags);
1082 	for (device = scsi_devs; device != NULL; device = device->next) {
1083 
1084 		/*
1085 		 * Watch out for duplicate devices.  This works around
1086 		 * some quirks in how the SCSI scanning code does its
1087 		 * device management.
1088 		 */
1089 		for (ldev = scsi_devs; ldev != device; ldev = ldev->next) {
1090 			if (ldev->host == device->host
1091 			 && ldev->channel == device->channel
1092 			 && ldev->id == device->id
1093 			 && ldev->lun == device->lun)
1094 				break;
1095 		}
1096 		/* Skip duplicate. */
1097 		if (ldev != device)
1098 			continue;
1099 
1100 		if (device->host == host) {
1101 			struct	 ahc_linux_device *dev;
1102 
1103 			/*
1104 			 * Since Linux has attached to the device, configure
1105 			 * it so we don't free and allocate the device
1106 			 * structure on every command.
1107 			 */
1108 			dev = ahc_linux_get_device(ahc, device->channel,
1109 						   device->id, device->lun,
1110 						   /*alloc*/TRUE);
1111 			if (dev != NULL) {
1112 				dev->flags &= ~AHC_DEV_UNCONFIGURED;
1113 				dev->scsi_device = device;
1114 				ahc_linux_device_queue_depth(ahc, dev);
1115 				device->queue_depth = dev->openings
1116 						    + dev->active;
1117 				if ((dev->flags & (AHC_DEV_Q_BASIC
1118 						| AHC_DEV_Q_TAGGED)) == 0) {
1119 					/*
1120 					 * We allow the OS to queue 2 untagged
1121 					 * transactions to us at any time even
1122 					 * though we can only execute them
1123 					 * serially on the controller/device.
1124 					 * This should remove some latency.
1125 					 */
1126 					device->queue_depth = 2;
1127 				}
1128 			}
1129 		}
1130 	}
1131 	ahc_unlock(ahc, &flags);
1132 }
1133 #endif
1134 
1135 #if defined(__i386__)
1136 /*
1137  * Return the disk geometry for the given SCSI device.
1138  */
1139 static int
1140 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
1141 ahc_linux_biosparam(struct scsi_device *sdev, struct block_device *bdev,
1142 		    sector_t capacity, int geom[])
1143 {
1144 	uint8_t *bh;
1145 #else
1146 ahc_linux_biosparam(Disk *disk, kdev_t dev, int geom[])
1147 {
1148 	struct	scsi_device *sdev = disk->device;
1149 	u_long	capacity = disk->capacity;
1150 	struct	buffer_head *bh;
1151 #endif
1152 	int	 heads;
1153 	int	 sectors;
1154 	int	 cylinders;
1155 	int	 ret;
1156 	int	 extended;
1157 	struct	 ahc_softc *ahc;
1158 	u_int	 channel;
1159 
1160 	ahc = *((struct ahc_softc **)sdev->host->hostdata);
1161 	channel = sdev->channel;
1162 
1163 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
1164 	bh = scsi_bios_ptable(bdev);
1165 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,17)
1166 	bh = bread(MKDEV(MAJOR(dev), MINOR(dev) & ~0xf), 0, block_size(dev));
1167 #else
1168 	bh = bread(MKDEV(MAJOR(dev), MINOR(dev) & ~0xf), 0, 1024);
1169 #endif
1170 
1171 	if (bh) {
1172 		ret = scsi_partsize(bh, capacity,
1173 				    &geom[2], &geom[0], &geom[1]);
1174 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
1175 		kfree(bh);
1176 #else
1177 		brelse(bh);
1178 #endif
1179 		if (ret != -1)
1180 			return (ret);
1181 	}
1182 	heads = 64;
1183 	sectors = 32;
1184 	cylinders = aic_sector_div(capacity, heads, sectors);
1185 
1186 	if (aic7xxx_extended != 0)
1187 		extended = 1;
1188 	else if (channel == 0)
1189 		extended = (ahc->flags & AHC_EXTENDED_TRANS_A) != 0;
1190 	else
1191 		extended = (ahc->flags & AHC_EXTENDED_TRANS_B) != 0;
1192 	if (extended && cylinders >= 1024) {
1193 		heads = 255;
1194 		sectors = 63;
1195 		cylinders = aic_sector_div(capacity, heads, sectors);
1196 	}
1197 	geom[0] = heads;
1198 	geom[1] = sectors;
1199 	geom[2] = cylinders;
1200 	return (0);
1201 }
1202 #endif
1203 
1204 /*
1205  * Abort the current SCSI command(s).
1206  */
1207 static int
1208 ahc_linux_abort(Scsi_Cmnd *cmd)
1209 {
1210 	int error;
1211 
1212 	error = ahc_linux_queue_recovery_cmd(cmd, SCB_ABORT);
1213 	if (error != 0)
1214 		printf("aic7xxx_abort returns 0x%x\n", error);
1215 	return (error);
1216 }
1217 
1218 /*
1219  * Attempt to send a target reset message to the device that timed out.
1220  */
1221 static int
1222 ahc_linux_dev_reset(Scsi_Cmnd *cmd)
1223 {
1224 	int error;
1225 
1226 	error = ahc_linux_queue_recovery_cmd(cmd, SCB_DEVICE_RESET);
1227 	if (error != 0)
1228 		printf("aic7xxx_dev_reset returns 0x%x\n", error);
1229 	return (error);
1230 }
1231 
1232 /*
1233  * Reset the SCSI bus.
1234  */
1235 static int
1236 ahc_linux_bus_reset(Scsi_Cmnd *cmd)
1237 {
1238 	struct ahc_softc *ahc;
1239 	u_long s;
1240 	int    found;
1241 
1242 	ahc = *(struct ahc_softc **)cmd->device->host->hostdata;
1243 	ahc_midlayer_entrypoint_lock(ahc, &s);
1244 	found = ahc_reset_channel(ahc, cmd->device->channel + 'A',
1245 				  /*initiate reset*/TRUE);
1246 	ahc_linux_run_complete_queue(ahc);
1247 	ahc_midlayer_entrypoint_unlock(ahc, &s);
1248 
1249 	if (bootverbose)
1250 		printf("%s: SCSI bus reset delivered. "
1251 		       "%d SCBs aborted.\n", ahc_name(ahc), found);
1252 
1253 	return SUCCESS;
1254 }
1255 
1256 Scsi_Host_Template aic7xxx_driver_template = {
1257 	.module			= THIS_MODULE,
1258 	.name			= "aic7xxx",
1259 	.proc_info		= ahc_linux_proc_info,
1260 	.info			= ahc_linux_info,
1261 	.queuecommand		= ahc_linux_queue,
1262 	.eh_abort_handler	= ahc_linux_abort,
1263 	.eh_device_reset_handler = ahc_linux_dev_reset,
1264 	.eh_bus_reset_handler	= ahc_linux_bus_reset,
1265 #if defined(__i386__)
1266 	.bios_param		= ahc_linux_biosparam,
1267 #endif
1268 	.can_queue		= AHC_MAX_QUEUE,
1269 	.this_id		= -1,
1270 	.cmd_per_lun		= 2,
1271 	.use_clustering		= ENABLE_CLUSTERING,
1272 	.slave_alloc		= ahc_linux_slave_alloc,
1273 	.slave_configure	= ahc_linux_slave_configure,
1274 	.slave_destroy		= ahc_linux_slave_destroy,
1275 };
1276 
1277 /**************************** Tasklet Handler *********************************/
1278 
1279 /*
1280  * In 2.4.X and above, this routine is called from a tasklet,
1281  * so we must re-acquire our lock prior to executing this code.
1282  * In all prior kernels, ahc_schedule_runq() calls this routine
1283  * directly and ahc_schedule_runq() is called with our lock held.
1284  */
1285 static void
1286 ahc_runq_tasklet(unsigned long data)
1287 {
1288 	struct ahc_softc* ahc;
1289 	struct ahc_linux_device *dev;
1290 	u_long flags;
1291 
1292 	ahc = (struct ahc_softc *)data;
1293 	ahc_lock(ahc, &flags);
1294 	while ((dev = ahc_linux_next_device_to_run(ahc)) != NULL) {
1295 
1296 		TAILQ_REMOVE(&ahc->platform_data->device_runq, dev, links);
1297 		dev->flags &= ~AHC_DEV_ON_RUN_LIST;
1298 		ahc_linux_check_device_queue(ahc, dev);
1299 		/* Yeild to our interrupt handler */
1300 		ahc_unlock(ahc, &flags);
1301 		ahc_lock(ahc, &flags);
1302 	}
1303 	ahc_unlock(ahc, &flags);
1304 }
1305 
1306 /******************************** Macros **************************************/
1307 #define BUILD_SCSIID(ahc, cmd)						    \
1308 	((((cmd)->device->id << TID_SHIFT) & TID)			    \
1309 	| (((cmd)->device->channel == 0) ? (ahc)->our_id : (ahc)->our_id_b) \
1310 	| (((cmd)->device->channel == 0) ? 0 : TWIN_CHNLB))
1311 
1312 /******************************** Bus DMA *************************************/
1313 int
1314 ahc_dma_tag_create(struct ahc_softc *ahc, bus_dma_tag_t parent,
1315 		   bus_size_t alignment, bus_size_t boundary,
1316 		   dma_addr_t lowaddr, dma_addr_t highaddr,
1317 		   bus_dma_filter_t *filter, void *filterarg,
1318 		   bus_size_t maxsize, int nsegments,
1319 		   bus_size_t maxsegsz, int flags, bus_dma_tag_t *ret_tag)
1320 {
1321 	bus_dma_tag_t dmat;
1322 
1323 	dmat = malloc(sizeof(*dmat), M_DEVBUF, M_NOWAIT);
1324 	if (dmat == NULL)
1325 		return (ENOMEM);
1326 
1327 	/*
1328 	 * Linux is very simplistic about DMA memory.  For now don't
1329 	 * maintain all specification information.  Once Linux supplies
1330 	 * better facilities for doing these operations, or the
1331 	 * needs of this particular driver change, we might need to do
1332 	 * more here.
1333 	 */
1334 	dmat->alignment = alignment;
1335 	dmat->boundary = boundary;
1336 	dmat->maxsize = maxsize;
1337 	*ret_tag = dmat;
1338 	return (0);
1339 }
1340 
1341 void
1342 ahc_dma_tag_destroy(struct ahc_softc *ahc, bus_dma_tag_t dmat)
1343 {
1344 	free(dmat, M_DEVBUF);
1345 }
1346 
1347 int
1348 ahc_dmamem_alloc(struct ahc_softc *ahc, bus_dma_tag_t dmat, void** vaddr,
1349 		 int flags, bus_dmamap_t *mapp)
1350 {
1351 	bus_dmamap_t map;
1352 
1353 	map = malloc(sizeof(*map), M_DEVBUF, M_NOWAIT);
1354 	if (map == NULL)
1355 		return (ENOMEM);
1356 	/*
1357 	 * Although we can dma data above 4GB, our
1358 	 * "consistent" memory is below 4GB for
1359 	 * space efficiency reasons (only need a 4byte
1360 	 * address).  For this reason, we have to reset
1361 	 * our dma mask when doing allocations.
1362 	 */
1363 	if (ahc->dev_softc != NULL)
1364 		if (pci_set_dma_mask(ahc->dev_softc, 0xFFFFFFFF)) {
1365 			printk(KERN_WARNING "aic7xxx: No suitable DMA available.\n");
1366 			kfree(map);
1367 			return (ENODEV);
1368 		}
1369 	*vaddr = pci_alloc_consistent(ahc->dev_softc,
1370 				      dmat->maxsize, &map->bus_addr);
1371 	if (ahc->dev_softc != NULL)
1372 		if (pci_set_dma_mask(ahc->dev_softc,
1373 				     ahc->platform_data->hw_dma_mask)) {
1374 			printk(KERN_WARNING "aic7xxx: No suitable DMA available.\n");
1375 			kfree(map);
1376 			return (ENODEV);
1377 		}
1378 	if (*vaddr == NULL)
1379 		return (ENOMEM);
1380 	*mapp = map;
1381 	return(0);
1382 }
1383 
1384 void
1385 ahc_dmamem_free(struct ahc_softc *ahc, bus_dma_tag_t dmat,
1386 		void* vaddr, bus_dmamap_t map)
1387 {
1388 	pci_free_consistent(ahc->dev_softc, dmat->maxsize,
1389 			    vaddr, map->bus_addr);
1390 }
1391 
1392 int
1393 ahc_dmamap_load(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map,
1394 		void *buf, bus_size_t buflen, bus_dmamap_callback_t *cb,
1395 		void *cb_arg, int flags)
1396 {
1397 	/*
1398 	 * Assume for now that this will only be used during
1399 	 * initialization and not for per-transaction buffer mapping.
1400 	 */
1401 	bus_dma_segment_t stack_sg;
1402 
1403 	stack_sg.ds_addr = map->bus_addr;
1404 	stack_sg.ds_len = dmat->maxsize;
1405 	cb(cb_arg, &stack_sg, /*nseg*/1, /*error*/0);
1406 	return (0);
1407 }
1408 
1409 void
1410 ahc_dmamap_destroy(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map)
1411 {
1412 	/*
1413 	 * The map may is NULL in our < 2.3.X implementation.
1414 	 * Now it's 2.6.5, but just in case...
1415 	 */
1416 	BUG_ON(map == NULL);
1417 	free(map, M_DEVBUF);
1418 }
1419 
1420 int
1421 ahc_dmamap_unload(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map)
1422 {
1423 	/* Nothing to do */
1424 	return (0);
1425 }
1426 
1427 /********************* Platform Dependent Functions ***************************/
1428 /*
1429  * Compare "left hand" softc with "right hand" softc, returning:
1430  * < 0 - lahc has a lower priority than rahc
1431  *   0 - Softcs are equal
1432  * > 0 - lahc has a higher priority than rahc
1433  */
1434 int
1435 ahc_softc_comp(struct ahc_softc *lahc, struct ahc_softc *rahc)
1436 {
1437 	int	value;
1438 	int	rvalue;
1439 	int	lvalue;
1440 
1441 	/*
1442 	 * Under Linux, cards are ordered as follows:
1443 	 *	1) VLB/EISA BIOS enabled devices sorted by BIOS address.
1444 	 *	2) PCI devices with BIOS enabled sorted by bus/slot/func.
1445 	 *	3) All remaining VLB/EISA devices sorted by ioport.
1446 	 *	4) All remaining PCI devices sorted by bus/slot/func.
1447 	 */
1448 	value = (lahc->flags & AHC_BIOS_ENABLED)
1449 	      - (rahc->flags & AHC_BIOS_ENABLED);
1450 	if (value != 0)
1451 		/* Controllers with BIOS enabled have a *higher* priority */
1452 		return (value);
1453 
1454 	/*
1455 	 * Same BIOS setting, now sort based on bus type.
1456 	 * EISA and VL controllers sort together.  EISA/VL
1457 	 * have higher priority than PCI.
1458 	 */
1459 	rvalue = (rahc->chip & AHC_BUS_MASK);
1460  	if (rvalue == AHC_VL)
1461 		rvalue = AHC_EISA;
1462 	lvalue = (lahc->chip & AHC_BUS_MASK);
1463  	if (lvalue == AHC_VL)
1464 		lvalue = AHC_EISA;
1465 	value = rvalue - lvalue;
1466 	if (value != 0)
1467 		return (value);
1468 
1469 	/* Still equal.  Sort by BIOS address, ioport, or bus/slot/func. */
1470 	switch (rvalue) {
1471 #ifdef CONFIG_PCI
1472 	case AHC_PCI:
1473 	{
1474 		char primary_channel;
1475 
1476 		if (aic7xxx_reverse_scan != 0)
1477 			value = ahc_get_pci_bus(lahc->dev_softc)
1478 			      - ahc_get_pci_bus(rahc->dev_softc);
1479 		else
1480 			value = ahc_get_pci_bus(rahc->dev_softc)
1481 			      - ahc_get_pci_bus(lahc->dev_softc);
1482 		if (value != 0)
1483 			break;
1484 		if (aic7xxx_reverse_scan != 0)
1485 			value = ahc_get_pci_slot(lahc->dev_softc)
1486 			      - ahc_get_pci_slot(rahc->dev_softc);
1487 		else
1488 			value = ahc_get_pci_slot(rahc->dev_softc)
1489 			      - ahc_get_pci_slot(lahc->dev_softc);
1490 		if (value != 0)
1491 			break;
1492 		/*
1493 		 * On multi-function devices, the user can choose
1494 		 * to have function 1 probed before function 0.
1495 		 * Give whichever channel is the primary channel
1496 		 * the highest priority.
1497 		 */
1498 		primary_channel = (lahc->flags & AHC_PRIMARY_CHANNEL) + 'A';
1499 		value = -1;
1500 		if (lahc->channel == primary_channel)
1501 			value = 1;
1502 		break;
1503 	}
1504 #endif
1505 	case AHC_EISA:
1506 		if ((rahc->flags & AHC_BIOS_ENABLED) != 0) {
1507 			value = rahc->platform_data->bios_address
1508 			      - lahc->platform_data->bios_address;
1509 		} else {
1510 			value = rahc->bsh.ioport
1511 			      - lahc->bsh.ioport;
1512 		}
1513 		break;
1514 	default:
1515 		panic("ahc_softc_sort: invalid bus type");
1516 	}
1517 	return (value);
1518 }
1519 
1520 static void
1521 ahc_linux_setup_tag_info_global(char *p)
1522 {
1523 	int tags, i, j;
1524 
1525 	tags = simple_strtoul(p + 1, NULL, 0) & 0xff;
1526 	printf("Setting Global Tags= %d\n", tags);
1527 
1528 	for (i = 0; i < NUM_ELEMENTS(aic7xxx_tag_info); i++) {
1529 		for (j = 0; j < AHC_NUM_TARGETS; j++) {
1530 			aic7xxx_tag_info[i].tag_commands[j] = tags;
1531 		}
1532 	}
1533 }
1534 
1535 static void
1536 ahc_linux_setup_tag_info(u_long arg, int instance, int targ, int32_t value)
1537 {
1538 
1539 	if ((instance >= 0) && (targ >= 0)
1540 	 && (instance < NUM_ELEMENTS(aic7xxx_tag_info))
1541 	 && (targ < AHC_NUM_TARGETS)) {
1542 		aic7xxx_tag_info[instance].tag_commands[targ] = value & 0xff;
1543 		if (bootverbose)
1544 			printf("tag_info[%d:%d] = %d\n", instance, targ, value);
1545 	}
1546 }
1547 
1548 static void
1549 ahc_linux_setup_dv(u_long arg, int instance, int targ, int32_t value)
1550 {
1551 
1552 	if ((instance >= 0)
1553 	 && (instance < NUM_ELEMENTS(aic7xxx_dv_settings))) {
1554 		aic7xxx_dv_settings[instance] = value;
1555 		if (bootverbose)
1556 			printf("dv[%d] = %d\n", instance, value);
1557 	}
1558 }
1559 
1560 /*
1561  * Handle Linux boot parameters. This routine allows for assigning a value
1562  * to a parameter with a ':' between the parameter and the value.
1563  * ie. aic7xxx=stpwlev:1,extended
1564  */
1565 static int
1566 aic7xxx_setup(char *s)
1567 {
1568 	int	i, n;
1569 	char   *p;
1570 	char   *end;
1571 
1572 	static struct {
1573 		const char *name;
1574 		uint32_t *flag;
1575 	} options[] = {
1576 		{ "extended", &aic7xxx_extended },
1577 		{ "no_reset", &aic7xxx_no_reset },
1578 		{ "verbose", &aic7xxx_verbose },
1579 		{ "allow_memio", &aic7xxx_allow_memio},
1580 #ifdef AHC_DEBUG
1581 		{ "debug", &ahc_debug },
1582 #endif
1583 		{ "reverse_scan", &aic7xxx_reverse_scan },
1584 		{ "no_probe", &aic7xxx_probe_eisa_vl },
1585 		{ "probe_eisa_vl", &aic7xxx_probe_eisa_vl },
1586 		{ "periodic_otag", &aic7xxx_periodic_otag },
1587 		{ "pci_parity", &aic7xxx_pci_parity },
1588 		{ "seltime", &aic7xxx_seltime },
1589 		{ "tag_info", NULL },
1590 		{ "global_tag_depth", NULL },
1591 		{ "dv", NULL }
1592 	};
1593 
1594 	end = strchr(s, '\0');
1595 
1596 	/*
1597 	 * XXX ia64 gcc isn't smart enough to know that NUM_ELEMENTS
1598 	 * will never be 0 in this case.
1599 	 */
1600 	n = 0;
1601 
1602 	while ((p = strsep(&s, ",.")) != NULL) {
1603 		if (*p == '\0')
1604 			continue;
1605 		for (i = 0; i < NUM_ELEMENTS(options); i++) {
1606 
1607 			n = strlen(options[i].name);
1608 			if (strncmp(options[i].name, p, n) == 0)
1609 				break;
1610 		}
1611 		if (i == NUM_ELEMENTS(options))
1612 			continue;
1613 
1614 		if (strncmp(p, "global_tag_depth", n) == 0) {
1615 			ahc_linux_setup_tag_info_global(p + n);
1616 		} else if (strncmp(p, "tag_info", n) == 0) {
1617 			s = aic_parse_brace_option("tag_info", p + n, end,
1618 			    2, ahc_linux_setup_tag_info, 0);
1619 		} else if (strncmp(p, "dv", n) == 0) {
1620 			s = aic_parse_brace_option("dv", p + n, end, 1,
1621 			    ahc_linux_setup_dv, 0);
1622 		} else if (p[n] == ':') {
1623 			*(options[i].flag) = simple_strtoul(p + n + 1, NULL, 0);
1624 		} else if (strncmp(p, "verbose", n) == 0) {
1625 			*(options[i].flag) = 1;
1626 		} else {
1627 			*(options[i].flag) ^= 0xFFFFFFFF;
1628 		}
1629 	}
1630 	return 1;
1631 }
1632 
1633 __setup("aic7xxx=", aic7xxx_setup);
1634 
1635 uint32_t aic7xxx_verbose;
1636 
1637 int
1638 ahc_linux_register_host(struct ahc_softc *ahc, Scsi_Host_Template *template)
1639 {
1640 	char	 buf[80];
1641 	struct	 Scsi_Host *host;
1642 	char	*new_name;
1643 	u_long	 s;
1644 	u_int	 targ_offset;
1645 
1646 	template->name = ahc->description;
1647 	host = scsi_host_alloc(template, sizeof(struct ahc_softc *));
1648 	if (host == NULL)
1649 		return (ENOMEM);
1650 
1651 	*((struct ahc_softc **)host->hostdata) = ahc;
1652 	ahc_lock(ahc, &s);
1653 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
1654 	scsi_assign_lock(host, &ahc->platform_data->spin_lock);
1655 #elif AHC_SCSI_HAS_HOST_LOCK != 0
1656 	host->lock = &ahc->platform_data->spin_lock;
1657 #endif
1658 	ahc->platform_data->host = host;
1659 	host->can_queue = AHC_MAX_QUEUE;
1660 	host->cmd_per_lun = 2;
1661 	/* XXX No way to communicate the ID for multiple channels */
1662 	host->this_id = ahc->our_id;
1663 	host->irq = ahc->platform_data->irq;
1664 	host->max_id = (ahc->features & AHC_WIDE) ? 16 : 8;
1665 	host->max_lun = AHC_NUM_LUNS;
1666 	host->max_channel = (ahc->features & AHC_TWIN) ? 1 : 0;
1667 	host->sg_tablesize = AHC_NSEG;
1668 	ahc_set_unit(ahc, ahc_linux_next_unit());
1669 	sprintf(buf, "scsi%d", host->host_no);
1670 	new_name = malloc(strlen(buf) + 1, M_DEVBUF, M_NOWAIT);
1671 	if (new_name != NULL) {
1672 		strcpy(new_name, buf);
1673 		ahc_set_name(ahc, new_name);
1674 	}
1675 	host->unique_id = ahc->unit;
1676 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
1677 	scsi_set_pci_device(host, ahc->dev_softc);
1678 #endif
1679 	ahc_linux_initialize_scsi_bus(ahc);
1680 	ahc_unlock(ahc, &s);
1681 	ahc->platform_data->dv_pid = kernel_thread(ahc_linux_dv_thread, ahc, 0);
1682 	ahc_lock(ahc, &s);
1683 	if (ahc->platform_data->dv_pid < 0) {
1684 		printf("%s: Failed to create DV thread, error= %d\n",
1685 		       ahc_name(ahc), ahc->platform_data->dv_pid);
1686 		return (-ahc->platform_data->dv_pid);
1687 	}
1688 	/*
1689 	 * Initially allocate *all* of our linux target objects
1690 	 * so that the DV thread will scan them all in parallel
1691 	 * just after driver initialization.  Any device that
1692 	 * does not exist will have its target object destroyed
1693 	 * by the selection timeout handler.  In the case of a
1694 	 * device that appears after the initial DV scan, async
1695 	 * negotiation will occur for the first command, and DV
1696 	 * will comence should that first command be successful.
1697 	 */
1698 	for (targ_offset = 0;
1699 	     targ_offset < host->max_id * (host->max_channel + 1);
1700 	     targ_offset++) {
1701 		u_int channel;
1702 		u_int target;
1703 
1704 		channel = 0;
1705 		target = targ_offset;
1706 		if (target > 7
1707 		 && (ahc->features & AHC_TWIN) != 0) {
1708 			channel = 1;
1709 			target &= 0x7;
1710 		}
1711 		/*
1712 		 * Skip our own ID.  Some Compaq/HP storage devices
1713 		 * have enclosure management devices that respond to
1714 		 * single bit selection (i.e. selecting ourselves).
1715 		 * It is expected that either an external application
1716 		 * or a modified kernel will be used to probe this
1717 		 * ID if it is appropriate.  To accommodate these
1718 		 * installations, ahc_linux_alloc_target() will allocate
1719 		 * for our ID if asked to do so.
1720 		 */
1721 		if ((channel == 0 && target == ahc->our_id)
1722 		 || (channel == 1 && target == ahc->our_id_b))
1723 			continue;
1724 
1725 		ahc_linux_alloc_target(ahc, channel, target);
1726 	}
1727 	ahc_intr_enable(ahc, TRUE);
1728 	ahc_linux_start_dv(ahc);
1729 	ahc_unlock(ahc, &s);
1730 
1731 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
1732 	scsi_add_host(host, (ahc->dev_softc ? &ahc->dev_softc->dev : NULL)); /* XXX handle failure */
1733 	scsi_scan_host(host);
1734 #endif
1735 	return (0);
1736 }
1737 
1738 uint64_t
1739 ahc_linux_get_memsize(void)
1740 {
1741 	struct sysinfo si;
1742 
1743 	si_meminfo(&si);
1744 	return ((uint64_t)si.totalram << PAGE_SHIFT);
1745 }
1746 
1747 /*
1748  * Find the smallest available unit number to use
1749  * for a new device.  We don't just use a static
1750  * count to handle the "repeated hot-(un)plug"
1751  * scenario.
1752  */
1753 static int
1754 ahc_linux_next_unit(void)
1755 {
1756 	struct ahc_softc *ahc;
1757 	int unit;
1758 
1759 	unit = 0;
1760 retry:
1761 	TAILQ_FOREACH(ahc, &ahc_tailq, links) {
1762 		if (ahc->unit == unit) {
1763 			unit++;
1764 			goto retry;
1765 		}
1766 	}
1767 	return (unit);
1768 }
1769 
1770 /*
1771  * Place the SCSI bus into a known state by either resetting it,
1772  * or forcing transfer negotiations on the next command to any
1773  * target.
1774  */
1775 void
1776 ahc_linux_initialize_scsi_bus(struct ahc_softc *ahc)
1777 {
1778 	int i;
1779 	int numtarg;
1780 
1781 	i = 0;
1782 	numtarg = 0;
1783 
1784 	if (aic7xxx_no_reset != 0)
1785 		ahc->flags &= ~(AHC_RESET_BUS_A|AHC_RESET_BUS_B);
1786 
1787 	if ((ahc->flags & AHC_RESET_BUS_A) != 0)
1788 		ahc_reset_channel(ahc, 'A', /*initiate_reset*/TRUE);
1789 	else
1790 		numtarg = (ahc->features & AHC_WIDE) ? 16 : 8;
1791 
1792 	if ((ahc->features & AHC_TWIN) != 0) {
1793 
1794 		if ((ahc->flags & AHC_RESET_BUS_B) != 0) {
1795 			ahc_reset_channel(ahc, 'B', /*initiate_reset*/TRUE);
1796 		} else {
1797 			if (numtarg == 0)
1798 				i = 8;
1799 			numtarg += 8;
1800 		}
1801 	}
1802 
1803 	/*
1804 	 * Force negotiation to async for all targets that
1805 	 * will not see an initial bus reset.
1806 	 */
1807 	for (; i < numtarg; i++) {
1808 		struct ahc_devinfo devinfo;
1809 		struct ahc_initiator_tinfo *tinfo;
1810 		struct ahc_tmode_tstate *tstate;
1811 		u_int our_id;
1812 		u_int target_id;
1813 		char channel;
1814 
1815 		channel = 'A';
1816 		our_id = ahc->our_id;
1817 		target_id = i;
1818 		if (i > 7 && (ahc->features & AHC_TWIN) != 0) {
1819 			channel = 'B';
1820 			our_id = ahc->our_id_b;
1821 			target_id = i % 8;
1822 		}
1823 		tinfo = ahc_fetch_transinfo(ahc, channel, our_id,
1824 					    target_id, &tstate);
1825 		ahc_compile_devinfo(&devinfo, our_id, target_id,
1826 				    CAM_LUN_WILDCARD, channel, ROLE_INITIATOR);
1827 		ahc_update_neg_request(ahc, &devinfo, tstate,
1828 				       tinfo, AHC_NEG_ALWAYS);
1829 	}
1830 	/* Give the bus some time to recover */
1831 	if ((ahc->flags & (AHC_RESET_BUS_A|AHC_RESET_BUS_B)) != 0) {
1832 		ahc_linux_freeze_simq(ahc);
1833 		init_timer(&ahc->platform_data->reset_timer);
1834 		ahc->platform_data->reset_timer.data = (u_long)ahc;
1835 		ahc->platform_data->reset_timer.expires =
1836 		    jiffies + (AIC7XXX_RESET_DELAY * HZ)/1000;
1837 		ahc->platform_data->reset_timer.function =
1838 		    ahc_linux_release_simq;
1839 		add_timer(&ahc->platform_data->reset_timer);
1840 	}
1841 }
1842 
1843 int
1844 ahc_platform_alloc(struct ahc_softc *ahc, void *platform_arg)
1845 {
1846 
1847 	ahc->platform_data =
1848 	    malloc(sizeof(struct ahc_platform_data), M_DEVBUF, M_NOWAIT);
1849 	if (ahc->platform_data == NULL)
1850 		return (ENOMEM);
1851 	memset(ahc->platform_data, 0, sizeof(struct ahc_platform_data));
1852 	TAILQ_INIT(&ahc->platform_data->completeq);
1853 	TAILQ_INIT(&ahc->platform_data->device_runq);
1854 	ahc->platform_data->irq = AHC_LINUX_NOIRQ;
1855 	ahc->platform_data->hw_dma_mask = 0xFFFFFFFF;
1856 	ahc_lockinit(ahc);
1857 	ahc_done_lockinit(ahc);
1858 	init_timer(&ahc->platform_data->completeq_timer);
1859 	ahc->platform_data->completeq_timer.data = (u_long)ahc;
1860 	ahc->platform_data->completeq_timer.function =
1861 	    (ahc_linux_callback_t *)ahc_linux_thread_run_complete_queue;
1862 	init_MUTEX_LOCKED(&ahc->platform_data->eh_sem);
1863 	init_MUTEX_LOCKED(&ahc->platform_data->dv_sem);
1864 	init_MUTEX_LOCKED(&ahc->platform_data->dv_cmd_sem);
1865 	tasklet_init(&ahc->platform_data->runq_tasklet, ahc_runq_tasklet,
1866 		     (unsigned long)ahc);
1867 	ahc->seltime = (aic7xxx_seltime & 0x3) << 4;
1868 	ahc->seltime_b = (aic7xxx_seltime & 0x3) << 4;
1869 	if (aic7xxx_pci_parity == 0)
1870 		ahc->flags |= AHC_DISABLE_PCI_PERR;
1871 
1872 	return (0);
1873 }
1874 
1875 void
1876 ahc_platform_free(struct ahc_softc *ahc)
1877 {
1878 	struct ahc_linux_target *targ;
1879 	struct ahc_linux_device *dev;
1880 	int i, j;
1881 
1882 	if (ahc->platform_data != NULL) {
1883 		del_timer_sync(&ahc->platform_data->completeq_timer);
1884 		ahc_linux_kill_dv_thread(ahc);
1885 		tasklet_kill(&ahc->platform_data->runq_tasklet);
1886 		if (ahc->platform_data->host != NULL) {
1887 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
1888 			scsi_remove_host(ahc->platform_data->host);
1889 #endif
1890 			scsi_host_put(ahc->platform_data->host);
1891 		}
1892 
1893 		/* destroy all of the device and target objects */
1894 		for (i = 0; i < AHC_NUM_TARGETS; i++) {
1895 			targ = ahc->platform_data->targets[i];
1896 			if (targ != NULL) {
1897 				/* Keep target around through the loop. */
1898 				targ->refcount++;
1899 				for (j = 0; j < AHC_NUM_LUNS; j++) {
1900 
1901 					if (targ->devices[j] == NULL)
1902 						continue;
1903 					dev = targ->devices[j];
1904 					ahc_linux_free_device(ahc, dev);
1905 				}
1906 				/*
1907 				 * Forcibly free the target now that
1908 				 * all devices are gone.
1909 				 */
1910 				ahc_linux_free_target(ahc, targ);
1911  			}
1912  		}
1913 
1914 		if (ahc->platform_data->irq != AHC_LINUX_NOIRQ)
1915 			free_irq(ahc->platform_data->irq, ahc);
1916 		if (ahc->tag == BUS_SPACE_PIO
1917 		 && ahc->bsh.ioport != 0)
1918 			release_region(ahc->bsh.ioport, 256);
1919 		if (ahc->tag == BUS_SPACE_MEMIO
1920 		 && ahc->bsh.maddr != NULL) {
1921 			iounmap(ahc->bsh.maddr);
1922 			release_mem_region(ahc->platform_data->mem_busaddr,
1923 					   0x1000);
1924 		}
1925 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
1926 		/*
1927 		 * In 2.4 we detach from the scsi midlayer before the PCI
1928 		 * layer invokes our remove callback.  No per-instance
1929 		 * detach is provided, so we must reach inside the PCI
1930 		 * subsystem's internals and detach our driver manually.
1931 		 */
1932 		if (ahc->dev_softc != NULL)
1933 			ahc->dev_softc->driver = NULL;
1934 #endif
1935 		free(ahc->platform_data, M_DEVBUF);
1936 	}
1937 }
1938 
1939 void
1940 ahc_platform_freeze_devq(struct ahc_softc *ahc, struct scb *scb)
1941 {
1942 	ahc_platform_abort_scbs(ahc, SCB_GET_TARGET(ahc, scb),
1943 				SCB_GET_CHANNEL(ahc, scb),
1944 				SCB_GET_LUN(scb), SCB_LIST_NULL,
1945 				ROLE_UNKNOWN, CAM_REQUEUE_REQ);
1946 }
1947 
1948 void
1949 ahc_platform_set_tags(struct ahc_softc *ahc, struct ahc_devinfo *devinfo,
1950 		      ahc_queue_alg alg)
1951 {
1952 	struct ahc_linux_device *dev;
1953 	int was_queuing;
1954 	int now_queuing;
1955 
1956 	dev = ahc_linux_get_device(ahc, devinfo->channel - 'A',
1957 				   devinfo->target,
1958 				   devinfo->lun, /*alloc*/FALSE);
1959 	if (dev == NULL)
1960 		return;
1961 	was_queuing = dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED);
1962 	switch (alg) {
1963 	default:
1964 	case AHC_QUEUE_NONE:
1965 		now_queuing = 0;
1966 		break;
1967 	case AHC_QUEUE_BASIC:
1968 		now_queuing = AHC_DEV_Q_BASIC;
1969 		break;
1970 	case AHC_QUEUE_TAGGED:
1971 		now_queuing = AHC_DEV_Q_TAGGED;
1972 		break;
1973 	}
1974 	if ((dev->flags & AHC_DEV_FREEZE_TIL_EMPTY) == 0
1975 	 && (was_queuing != now_queuing)
1976 	 && (dev->active != 0)) {
1977 		dev->flags |= AHC_DEV_FREEZE_TIL_EMPTY;
1978 		dev->qfrozen++;
1979 	}
1980 
1981 	dev->flags &= ~(AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED|AHC_DEV_PERIODIC_OTAG);
1982 	if (now_queuing) {
1983 		u_int usertags;
1984 
1985 		usertags = ahc_linux_user_tagdepth(ahc, devinfo);
1986 		if (!was_queuing) {
1987 			/*
1988 			 * Start out agressively and allow our
1989 			 * dynamic queue depth algorithm to take
1990 			 * care of the rest.
1991 			 */
1992 			dev->maxtags = usertags;
1993 			dev->openings = dev->maxtags - dev->active;
1994 		}
1995 		if (dev->maxtags == 0) {
1996 			/*
1997 			 * Queueing is disabled by the user.
1998 			 */
1999 			dev->openings = 1;
2000 		} else if (alg == AHC_QUEUE_TAGGED) {
2001 			dev->flags |= AHC_DEV_Q_TAGGED;
2002 			if (aic7xxx_periodic_otag != 0)
2003 				dev->flags |= AHC_DEV_PERIODIC_OTAG;
2004 		} else
2005 			dev->flags |= AHC_DEV_Q_BASIC;
2006 	} else {
2007 		/* We can only have one opening. */
2008 		dev->maxtags = 0;
2009 		dev->openings =  1 - dev->active;
2010 	}
2011 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
2012 	if (dev->scsi_device != NULL) {
2013 		switch ((dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED))) {
2014 		case AHC_DEV_Q_BASIC:
2015 			scsi_adjust_queue_depth(dev->scsi_device,
2016 						MSG_SIMPLE_TASK,
2017 						dev->openings + dev->active);
2018 			break;
2019 		case AHC_DEV_Q_TAGGED:
2020 			scsi_adjust_queue_depth(dev->scsi_device,
2021 						MSG_ORDERED_TASK,
2022 						dev->openings + dev->active);
2023 			break;
2024 		default:
2025 			/*
2026 			 * We allow the OS to queue 2 untagged transactions to
2027 			 * us at any time even though we can only execute them
2028 			 * serially on the controller/device.  This should
2029 			 * remove some latency.
2030 			 */
2031 			scsi_adjust_queue_depth(dev->scsi_device,
2032 						/*NON-TAGGED*/0,
2033 						/*queue depth*/2);
2034 			break;
2035 		}
2036 	}
2037 #endif
2038 }
2039 
2040 int
2041 ahc_platform_abort_scbs(struct ahc_softc *ahc, int target, char channel,
2042 			int lun, u_int tag, role_t role, uint32_t status)
2043 {
2044 	int chan;
2045 	int maxchan;
2046 	int targ;
2047 	int maxtarg;
2048 	int clun;
2049 	int maxlun;
2050 	int count;
2051 
2052 	if (tag != SCB_LIST_NULL)
2053 		return (0);
2054 
2055 	chan = 0;
2056 	if (channel != ALL_CHANNELS) {
2057 		chan = channel - 'A';
2058 		maxchan = chan + 1;
2059 	} else {
2060 		maxchan = (ahc->features & AHC_TWIN) ? 2 : 1;
2061 	}
2062 	targ = 0;
2063 	if (target != CAM_TARGET_WILDCARD) {
2064 		targ = target;
2065 		maxtarg = targ + 1;
2066 	} else {
2067 		maxtarg = (ahc->features & AHC_WIDE) ? 16 : 8;
2068 	}
2069 	clun = 0;
2070 	if (lun != CAM_LUN_WILDCARD) {
2071 		clun = lun;
2072 		maxlun = clun + 1;
2073 	} else {
2074 		maxlun = AHC_NUM_LUNS;
2075 	}
2076 
2077 	count = 0;
2078 	for (; chan < maxchan; chan++) {
2079 
2080 		for (; targ < maxtarg; targ++) {
2081 
2082 			for (; clun < maxlun; clun++) {
2083 				struct ahc_linux_device *dev;
2084 				struct ahc_busyq *busyq;
2085 				struct ahc_cmd *acmd;
2086 
2087 				dev = ahc_linux_get_device(ahc, chan,
2088 							   targ, clun,
2089 							   /*alloc*/FALSE);
2090 				if (dev == NULL)
2091 					continue;
2092 
2093 				busyq = &dev->busyq;
2094 				while ((acmd = TAILQ_FIRST(busyq)) != NULL) {
2095 					Scsi_Cmnd *cmd;
2096 
2097 					cmd = &acmd_scsi_cmd(acmd);
2098 					TAILQ_REMOVE(busyq, acmd,
2099 						     acmd_links.tqe);
2100 					count++;
2101 					cmd->result = status << 16;
2102 					ahc_linux_queue_cmd_complete(ahc, cmd);
2103 				}
2104 			}
2105 		}
2106 	}
2107 
2108 	return (count);
2109 }
2110 
2111 static void
2112 ahc_linux_thread_run_complete_queue(struct ahc_softc *ahc)
2113 {
2114 	u_long flags;
2115 
2116 	ahc_lock(ahc, &flags);
2117 	del_timer(&ahc->platform_data->completeq_timer);
2118 	ahc->platform_data->flags &= ~AHC_RUN_CMPLT_Q_TIMER;
2119 	ahc_linux_run_complete_queue(ahc);
2120 	ahc_unlock(ahc, &flags);
2121 }
2122 
2123 static void
2124 ahc_linux_start_dv(struct ahc_softc *ahc)
2125 {
2126 
2127 	/*
2128 	 * Freeze the simq and signal ahc_linux_queue to not let any
2129 	 * more commands through.
2130 	 */
2131 	if ((ahc->platform_data->flags & AHC_DV_ACTIVE) == 0) {
2132 #ifdef AHC_DEBUG
2133 		if (ahc_debug & AHC_SHOW_DV)
2134 			printf("%s: Waking DV thread\n", ahc_name(ahc));
2135 #endif
2136 
2137 		ahc->platform_data->flags |= AHC_DV_ACTIVE;
2138 		ahc_linux_freeze_simq(ahc);
2139 
2140 		/* Wake up the DV kthread */
2141 		up(&ahc->platform_data->dv_sem);
2142 	}
2143 }
2144 
2145 static void
2146 ahc_linux_kill_dv_thread(struct ahc_softc *ahc)
2147 {
2148 	u_long s;
2149 
2150 	ahc_lock(ahc, &s);
2151 	if (ahc->platform_data->dv_pid != 0) {
2152 		ahc->platform_data->flags |= AHC_DV_SHUTDOWN;
2153 		ahc_unlock(ahc, &s);
2154 		up(&ahc->platform_data->dv_sem);
2155 
2156 		/*
2157 		 * Use the eh_sem as an indicator that the
2158 		 * dv thread is exiting.  Note that the dv
2159 		 * thread must still return after performing
2160 		 * the up on our semaphore before it has
2161 		 * completely exited this module.  Unfortunately,
2162 		 * there seems to be no easy way to wait for the
2163 		 * exit of a thread for which you are not the
2164 		 * parent (dv threads are parented by init).
2165 		 * Cross your fingers...
2166 		 */
2167 		down(&ahc->platform_data->eh_sem);
2168 
2169 		/*
2170 		 * Mark the dv thread as already dead.  This
2171 		 * avoids attempting to kill it a second time.
2172 		 * This is necessary because we must kill the
2173 		 * DV thread before calling ahc_free() in the
2174 		 * module shutdown case to avoid bogus locking
2175 		 * in the SCSI mid-layer, but we ahc_free() is
2176 		 * called without killing the DV thread in the
2177 		 * instance detach case, so ahc_platform_free()
2178 		 * calls us again to verify that the DV thread
2179 		 * is dead.
2180 		 */
2181 		ahc->platform_data->dv_pid = 0;
2182 	} else {
2183 		ahc_unlock(ahc, &s);
2184 	}
2185 }
2186 
2187 static int
2188 ahc_linux_dv_thread(void *data)
2189 {
2190 	struct	ahc_softc *ahc;
2191 	int	target;
2192 	u_long	s;
2193 
2194 	ahc = (struct ahc_softc *)data;
2195 
2196 #ifdef AHC_DEBUG
2197 	if (ahc_debug & AHC_SHOW_DV)
2198 		printf("Launching DV Thread\n");
2199 #endif
2200 
2201 	/*
2202 	 * Complete thread creation.
2203 	 */
2204 	lock_kernel();
2205 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
2206 	/*
2207 	 * Don't care about any signals.
2208 	 */
2209 	siginitsetinv(&current->blocked, 0);
2210 
2211 	daemonize();
2212 	sprintf(current->comm, "ahc_dv_%d", ahc->unit);
2213 #else
2214 	daemonize("ahc_dv_%d", ahc->unit);
2215 	current->flags |= PF_FREEZE;
2216 #endif
2217 	unlock_kernel();
2218 
2219 	while (1) {
2220 		/*
2221 		 * Use down_interruptible() rather than down() to
2222 		 * avoid inclusion in the load average.
2223 		 */
2224 		down_interruptible(&ahc->platform_data->dv_sem);
2225 
2226 		/* Check to see if we've been signaled to exit */
2227 		ahc_lock(ahc, &s);
2228 		if ((ahc->platform_data->flags & AHC_DV_SHUTDOWN) != 0) {
2229 			ahc_unlock(ahc, &s);
2230 			break;
2231 		}
2232 		ahc_unlock(ahc, &s);
2233 
2234 #ifdef AHC_DEBUG
2235 		if (ahc_debug & AHC_SHOW_DV)
2236 			printf("%s: Beginning Domain Validation\n",
2237 			       ahc_name(ahc));
2238 #endif
2239 
2240 		/*
2241 		 * Wait for any pending commands to drain before proceeding.
2242 		 */
2243 		ahc_lock(ahc, &s);
2244 		while (LIST_FIRST(&ahc->pending_scbs) != NULL) {
2245 			ahc->platform_data->flags |= AHC_DV_WAIT_SIMQ_EMPTY;
2246 			ahc_unlock(ahc, &s);
2247 			down_interruptible(&ahc->platform_data->dv_sem);
2248 			ahc_lock(ahc, &s);
2249 		}
2250 
2251 		/*
2252 		 * Wait for the SIMQ to be released so that DV is the
2253 		 * only reason the queue is frozen.
2254 		 */
2255 		while (AHC_DV_SIMQ_FROZEN(ahc) == 0) {
2256 			ahc->platform_data->flags |= AHC_DV_WAIT_SIMQ_RELEASE;
2257 			ahc_unlock(ahc, &s);
2258 			down_interruptible(&ahc->platform_data->dv_sem);
2259 			ahc_lock(ahc, &s);
2260 		}
2261 		ahc_unlock(ahc, &s);
2262 
2263 		for (target = 0; target < AHC_NUM_TARGETS; target++)
2264 			ahc_linux_dv_target(ahc, target);
2265 
2266 		ahc_lock(ahc, &s);
2267 		ahc->platform_data->flags &= ~AHC_DV_ACTIVE;
2268 		ahc_unlock(ahc, &s);
2269 
2270 		/*
2271 		 * Release the SIMQ so that normal commands are
2272 		 * allowed to continue on the bus.
2273 		 */
2274 		ahc_linux_release_simq((u_long)ahc);
2275 	}
2276 	up(&ahc->platform_data->eh_sem);
2277 	return (0);
2278 }
2279 
2280 #define AHC_LINUX_DV_INQ_SHORT_LEN	36
2281 #define AHC_LINUX_DV_INQ_LEN		256
2282 #define AHC_LINUX_DV_TIMEOUT		(HZ / 4)
2283 
2284 #define AHC_SET_DV_STATE(ahc, targ, newstate) \
2285 	ahc_set_dv_state(ahc, targ, newstate, __LINE__)
2286 
2287 static __inline void
2288 ahc_set_dv_state(struct ahc_softc *ahc, struct ahc_linux_target *targ,
2289 		 ahc_dv_state newstate, u_int line)
2290 {
2291 	ahc_dv_state oldstate;
2292 
2293 	oldstate = targ->dv_state;
2294 #ifdef AHC_DEBUG
2295 	if (ahc_debug & AHC_SHOW_DV)
2296 		printf("%s:%d: Going from state %d to state %d\n",
2297 		       ahc_name(ahc), line, oldstate, newstate);
2298 #endif
2299 
2300 	if (oldstate == newstate)
2301 		targ->dv_state_retry++;
2302 	else
2303 		targ->dv_state_retry = 0;
2304 	targ->dv_state = newstate;
2305 }
2306 
2307 static void
2308 ahc_linux_dv_target(struct ahc_softc *ahc, u_int target_offset)
2309 {
2310 	struct	 ahc_devinfo devinfo;
2311 	struct	 ahc_linux_target *targ;
2312 	struct	 scsi_cmnd *cmd;
2313 	struct	 scsi_device *scsi_dev;
2314 	struct	 scsi_sense_data *sense;
2315 	uint8_t *buffer;
2316 	u_long	 s;
2317 	u_int	 timeout;
2318 	int	 echo_size;
2319 
2320 	sense = NULL;
2321 	buffer = NULL;
2322 	echo_size = 0;
2323 	ahc_lock(ahc, &s);
2324 	targ = ahc->platform_data->targets[target_offset];
2325 	if (targ == NULL || (targ->flags & AHC_DV_REQUIRED) == 0) {
2326 		ahc_unlock(ahc, &s);
2327 		return;
2328 	}
2329 	ahc_compile_devinfo(&devinfo,
2330 			    targ->channel == 0 ? ahc->our_id : ahc->our_id_b,
2331 			    targ->target, /*lun*/0, targ->channel + 'A',
2332 			    ROLE_INITIATOR);
2333 #ifdef AHC_DEBUG
2334 	if (ahc_debug & AHC_SHOW_DV) {
2335 		ahc_print_devinfo(ahc, &devinfo);
2336 		printf("Performing DV\n");
2337 	}
2338 #endif
2339 
2340 	ahc_unlock(ahc, &s);
2341 
2342 	cmd = malloc(sizeof(struct scsi_cmnd), M_DEVBUF, M_WAITOK);
2343 	scsi_dev = malloc(sizeof(struct scsi_device), M_DEVBUF, M_WAITOK);
2344 	scsi_dev->host = ahc->platform_data->host;
2345 	scsi_dev->id = devinfo.target;
2346 	scsi_dev->lun = devinfo.lun;
2347 	scsi_dev->channel = devinfo.channel - 'A';
2348 	ahc->platform_data->dv_scsi_dev = scsi_dev;
2349 
2350 	AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_INQ_SHORT_ASYNC);
2351 
2352 	while (targ->dv_state != AHC_DV_STATE_EXIT) {
2353 		timeout = AHC_LINUX_DV_TIMEOUT;
2354 		switch (targ->dv_state) {
2355 		case AHC_DV_STATE_INQ_SHORT_ASYNC:
2356 		case AHC_DV_STATE_INQ_ASYNC:
2357 		case AHC_DV_STATE_INQ_ASYNC_VERIFY:
2358 			/*
2359 			 * Set things to async narrow to reduce the
2360 			 * chance that the INQ will fail.
2361 			 */
2362 			ahc_lock(ahc, &s);
2363 			ahc_set_syncrate(ahc, &devinfo, NULL, 0, 0, 0,
2364 					 AHC_TRANS_GOAL, /*paused*/FALSE);
2365 			ahc_set_width(ahc, &devinfo, MSG_EXT_WDTR_BUS_8_BIT,
2366 				      AHC_TRANS_GOAL, /*paused*/FALSE);
2367 			ahc_unlock(ahc, &s);
2368 			timeout = 10 * HZ;
2369 			targ->flags &= ~AHC_INQ_VALID;
2370 			/* FALLTHROUGH */
2371 		case AHC_DV_STATE_INQ_VERIFY:
2372 		{
2373 			u_int inq_len;
2374 
2375 			if (targ->dv_state == AHC_DV_STATE_INQ_SHORT_ASYNC)
2376 				inq_len = AHC_LINUX_DV_INQ_SHORT_LEN;
2377 			else
2378 				inq_len = targ->inq_data->additional_length + 5;
2379 			ahc_linux_dv_inq(ahc, cmd, &devinfo, targ, inq_len);
2380 			break;
2381 		}
2382 		case AHC_DV_STATE_TUR:
2383 		case AHC_DV_STATE_BUSY:
2384 			timeout = 5 * HZ;
2385 			ahc_linux_dv_tur(ahc, cmd, &devinfo);
2386 			break;
2387 		case AHC_DV_STATE_REBD:
2388 			ahc_linux_dv_rebd(ahc, cmd, &devinfo, targ);
2389 			break;
2390 		case AHC_DV_STATE_WEB:
2391 			ahc_linux_dv_web(ahc, cmd, &devinfo, targ);
2392 			break;
2393 
2394 		case AHC_DV_STATE_REB:
2395 			ahc_linux_dv_reb(ahc, cmd, &devinfo, targ);
2396 			break;
2397 
2398 		case AHC_DV_STATE_SU:
2399 			ahc_linux_dv_su(ahc, cmd, &devinfo, targ);
2400 			timeout = 50 * HZ;
2401 			break;
2402 
2403 		default:
2404 			ahc_print_devinfo(ahc, &devinfo);
2405 			printf("Unknown DV state %d\n", targ->dv_state);
2406 			goto out;
2407 		}
2408 
2409 		/* Queue the command and wait for it to complete */
2410 		/* Abuse eh_timeout in the scsi_cmnd struct for our purposes */
2411 		init_timer(&cmd->eh_timeout);
2412 #ifdef AHC_DEBUG
2413 		if ((ahc_debug & AHC_SHOW_MESSAGES) != 0)
2414 			/*
2415 			 * All of the printfs during negotiation
2416 			 * really slow down the negotiation.
2417 			 * Add a bit of time just to be safe.
2418 			 */
2419 			timeout += HZ;
2420 #endif
2421 		scsi_add_timer(cmd, timeout, ahc_linux_dv_timeout);
2422 		/*
2423 		 * In 2.5.X, it is assumed that all calls from the
2424 		 * "midlayer" (which we are emulating) will have the
2425 		 * ahc host lock held.  For other kernels, the
2426 		 * io_request_lock must be held.
2427 		 */
2428 #if AHC_SCSI_HAS_HOST_LOCK != 0
2429 		ahc_lock(ahc, &s);
2430 #else
2431 		spin_lock_irqsave(&io_request_lock, s);
2432 #endif
2433 		ahc_linux_queue(cmd, ahc_linux_dv_complete);
2434 #if AHC_SCSI_HAS_HOST_LOCK != 0
2435 		ahc_unlock(ahc, &s);
2436 #else
2437 		spin_unlock_irqrestore(&io_request_lock, s);
2438 #endif
2439 		down_interruptible(&ahc->platform_data->dv_cmd_sem);
2440 		/*
2441 		 * Wait for the SIMQ to be released so that DV is the
2442 		 * only reason the queue is frozen.
2443 		 */
2444 		ahc_lock(ahc, &s);
2445 		while (AHC_DV_SIMQ_FROZEN(ahc) == 0) {
2446 			ahc->platform_data->flags |= AHC_DV_WAIT_SIMQ_RELEASE;
2447 			ahc_unlock(ahc, &s);
2448 			down_interruptible(&ahc->platform_data->dv_sem);
2449 			ahc_lock(ahc, &s);
2450 		}
2451 		ahc_unlock(ahc, &s);
2452 
2453 		ahc_linux_dv_transition(ahc, cmd, &devinfo, targ);
2454 	}
2455 
2456 out:
2457 	if ((targ->flags & AHC_INQ_VALID) != 0
2458 	 && ahc_linux_get_device(ahc, devinfo.channel - 'A',
2459 				 devinfo.target, devinfo.lun,
2460 				 /*alloc*/FALSE) == NULL) {
2461 		/*
2462 		 * The DV state machine failed to configure this device.
2463 		 * This is normal if DV is disabled.  Since we have inquiry
2464 		 * data, filter it and use the "optimistic" negotiation
2465 		 * parameters found in the inquiry string.
2466 		 */
2467 		ahc_linux_filter_inquiry(ahc, &devinfo);
2468 		if ((targ->flags & (AHC_BASIC_DV|AHC_ENHANCED_DV)) != 0) {
2469 			ahc_print_devinfo(ahc, &devinfo);
2470 			printf("DV failed to configure device.  "
2471 			       "Please file a bug report against "
2472 			       "this driver.\n");
2473 		}
2474 	}
2475 
2476 	if (cmd != NULL)
2477 		free(cmd, M_DEVBUF);
2478 
2479 	if (ahc->platform_data->dv_scsi_dev != NULL) {
2480 		free(ahc->platform_data->dv_scsi_dev, M_DEVBUF);
2481 		ahc->platform_data->dv_scsi_dev = NULL;
2482 	}
2483 
2484 	ahc_lock(ahc, &s);
2485 	if (targ->dv_buffer != NULL) {
2486 		free(targ->dv_buffer, M_DEVBUF);
2487 		targ->dv_buffer = NULL;
2488 	}
2489 	if (targ->dv_buffer1 != NULL) {
2490 		free(targ->dv_buffer1, M_DEVBUF);
2491 		targ->dv_buffer1 = NULL;
2492 	}
2493 	targ->flags &= ~AHC_DV_REQUIRED;
2494 	if (targ->refcount == 0)
2495 		ahc_linux_free_target(ahc, targ);
2496 	ahc_unlock(ahc, &s);
2497 }
2498 
2499 static void
2500 ahc_linux_dv_transition(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
2501 			struct ahc_devinfo *devinfo,
2502 			struct ahc_linux_target *targ)
2503 {
2504 	u_int32_t status;
2505 
2506 	status = aic_error_action(cmd, targ->inq_data,
2507 				  ahc_cmd_get_transaction_status(cmd),
2508 				  ahc_cmd_get_scsi_status(cmd));
2509 
2510 #ifdef AHC_DEBUG
2511 	if (ahc_debug & AHC_SHOW_DV) {
2512 		ahc_print_devinfo(ahc, devinfo);
2513 		printf("Entering ahc_linux_dv_transition, state= %d, "
2514 		       "status= 0x%x, cmd->result= 0x%x\n", targ->dv_state,
2515 		       status, cmd->result);
2516 	}
2517 #endif
2518 
2519 	switch (targ->dv_state) {
2520 	case AHC_DV_STATE_INQ_SHORT_ASYNC:
2521 	case AHC_DV_STATE_INQ_ASYNC:
2522 		switch (status & SS_MASK) {
2523 		case SS_NOP:
2524 		{
2525 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state+1);
2526 			break;
2527 		}
2528 		case SS_INQ_REFRESH:
2529 			AHC_SET_DV_STATE(ahc, targ,
2530 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2531 			break;
2532 		case SS_TUR:
2533 		case SS_RETRY:
2534 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2535 			if (ahc_cmd_get_transaction_status(cmd)
2536 			 == CAM_REQUEUE_REQ)
2537 				targ->dv_state_retry--;
2538 			if ((status & SS_ERRMASK) == EBUSY)
2539 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_BUSY);
2540 			if (targ->dv_state_retry < 10)
2541 				break;
2542 			/* FALLTHROUGH */
2543 		default:
2544 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2545 #ifdef AHC_DEBUG
2546 			if (ahc_debug & AHC_SHOW_DV) {
2547 				ahc_print_devinfo(ahc, devinfo);
2548 				printf("Failed DV inquiry, skipping\n");
2549 			}
2550 #endif
2551 			break;
2552 		}
2553 		break;
2554 	case AHC_DV_STATE_INQ_ASYNC_VERIFY:
2555 		switch (status & SS_MASK) {
2556 		case SS_NOP:
2557 		{
2558 			u_int xportflags;
2559 			u_int spi3data;
2560 
2561 			if (memcmp(targ->inq_data, targ->dv_buffer,
2562 				   AHC_LINUX_DV_INQ_LEN) != 0) {
2563 				/*
2564 				 * Inquiry data must have changed.
2565 				 * Try from the top again.
2566 				 */
2567 				AHC_SET_DV_STATE(ahc, targ,
2568 						 AHC_DV_STATE_INQ_SHORT_ASYNC);
2569 				break;
2570 			}
2571 
2572 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state+1);
2573 			targ->flags |= AHC_INQ_VALID;
2574 			if (ahc_linux_user_dv_setting(ahc) == 0)
2575 				break;
2576 
2577 			xportflags = targ->inq_data->flags;
2578 			if ((xportflags & (SID_Sync|SID_WBus16)) == 0)
2579 				break;
2580 
2581 			spi3data = targ->inq_data->spi3data;
2582 			switch (spi3data & SID_SPI_CLOCK_DT_ST) {
2583 			default:
2584 			case SID_SPI_CLOCK_ST:
2585 				/* Assume only basic DV is supported. */
2586 				targ->flags |= AHC_BASIC_DV;
2587 				break;
2588 			case SID_SPI_CLOCK_DT:
2589 			case SID_SPI_CLOCK_DT_ST:
2590 				targ->flags |= AHC_ENHANCED_DV;
2591 				break;
2592 			}
2593 			break;
2594 		}
2595 		case SS_INQ_REFRESH:
2596 			AHC_SET_DV_STATE(ahc, targ,
2597 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2598 			break;
2599 		case SS_TUR:
2600 		case SS_RETRY:
2601 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2602 			if (ahc_cmd_get_transaction_status(cmd)
2603 			 == CAM_REQUEUE_REQ)
2604 				targ->dv_state_retry--;
2605 
2606 			if ((status & SS_ERRMASK) == EBUSY)
2607 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_BUSY);
2608 			if (targ->dv_state_retry < 10)
2609 				break;
2610 			/* FALLTHROUGH */
2611 		default:
2612 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2613 #ifdef AHC_DEBUG
2614 			if (ahc_debug & AHC_SHOW_DV) {
2615 				ahc_print_devinfo(ahc, devinfo);
2616 				printf("Failed DV inquiry, skipping\n");
2617 			}
2618 #endif
2619 			break;
2620 		}
2621 		break;
2622 	case AHC_DV_STATE_INQ_VERIFY:
2623 		switch (status & SS_MASK) {
2624 		case SS_NOP:
2625 		{
2626 
2627 			if (memcmp(targ->inq_data, targ->dv_buffer,
2628 				   AHC_LINUX_DV_INQ_LEN) == 0) {
2629 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2630 				break;
2631 			}
2632 #ifdef AHC_DEBUG
2633 			if (ahc_debug & AHC_SHOW_DV) {
2634 				int i;
2635 
2636 				ahc_print_devinfo(ahc, devinfo);
2637 				printf("Inquiry buffer mismatch:");
2638 				for (i = 0; i < AHC_LINUX_DV_INQ_LEN; i++) {
2639 					if ((i & 0xF) == 0)
2640 						printf("\n        ");
2641 					printf("0x%x:0x0%x ",
2642 					       ((uint8_t *)targ->inq_data)[i],
2643 					       targ->dv_buffer[i]);
2644 				}
2645 				printf("\n");
2646 			}
2647 #endif
2648 
2649 			if (ahc_linux_fallback(ahc, devinfo) != 0) {
2650 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2651 				break;
2652 			}
2653 			/*
2654 			 * Do not count "falling back"
2655 			 * against our retries.
2656 			 */
2657 			targ->dv_state_retry = 0;
2658 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2659 			break;
2660 		}
2661 		case SS_INQ_REFRESH:
2662 			AHC_SET_DV_STATE(ahc, targ,
2663 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2664 			break;
2665 		case SS_TUR:
2666 		case SS_RETRY:
2667 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2668 			if (ahc_cmd_get_transaction_status(cmd)
2669 			 == CAM_REQUEUE_REQ) {
2670 				targ->dv_state_retry--;
2671 			} else if ((status & SSQ_FALLBACK) != 0) {
2672 				if (ahc_linux_fallback(ahc, devinfo) != 0) {
2673 					AHC_SET_DV_STATE(ahc, targ,
2674 							 AHC_DV_STATE_EXIT);
2675 					break;
2676 				}
2677 				/*
2678 				 * Do not count "falling back"
2679 				 * against our retries.
2680 				 */
2681 				targ->dv_state_retry = 0;
2682 			} else if ((status & SS_ERRMASK) == EBUSY)
2683 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_BUSY);
2684 			if (targ->dv_state_retry < 10)
2685 				break;
2686 			/* FALLTHROUGH */
2687 		default:
2688 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2689 #ifdef AHC_DEBUG
2690 			if (ahc_debug & AHC_SHOW_DV) {
2691 				ahc_print_devinfo(ahc, devinfo);
2692 				printf("Failed DV inquiry, skipping\n");
2693 			}
2694 #endif
2695 			break;
2696 		}
2697 		break;
2698 
2699 	case AHC_DV_STATE_TUR:
2700 		switch (status & SS_MASK) {
2701 		case SS_NOP:
2702 			if ((targ->flags & AHC_BASIC_DV) != 0) {
2703 				ahc_linux_filter_inquiry(ahc, devinfo);
2704 				AHC_SET_DV_STATE(ahc, targ,
2705 						 AHC_DV_STATE_INQ_VERIFY);
2706 			} else if ((targ->flags & AHC_ENHANCED_DV) != 0) {
2707 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_REBD);
2708 			} else {
2709 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2710 			}
2711 			break;
2712 		case SS_RETRY:
2713 		case SS_TUR:
2714 			if ((status & SS_ERRMASK) == EBUSY) {
2715 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_BUSY);
2716 				break;
2717 			}
2718 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2719 			if (ahc_cmd_get_transaction_status(cmd)
2720 			 == CAM_REQUEUE_REQ) {
2721 				targ->dv_state_retry--;
2722 			} else if ((status & SSQ_FALLBACK) != 0) {
2723 				if (ahc_linux_fallback(ahc, devinfo) != 0) {
2724 					AHC_SET_DV_STATE(ahc, targ,
2725 							 AHC_DV_STATE_EXIT);
2726 					break;
2727 				}
2728 				/*
2729 				 * Do not count "falling back"
2730 				 * against our retries.
2731 				 */
2732 				targ->dv_state_retry = 0;
2733 			}
2734 			if (targ->dv_state_retry >= 10) {
2735 #ifdef AHC_DEBUG
2736 				if (ahc_debug & AHC_SHOW_DV) {
2737 					ahc_print_devinfo(ahc, devinfo);
2738 					printf("DV TUR reties exhausted\n");
2739 				}
2740 #endif
2741 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2742 				break;
2743 			}
2744 			if (status & SSQ_DELAY)
2745 				ssleep(1);
2746 
2747 			break;
2748 		case SS_START:
2749 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_SU);
2750 			break;
2751 		case SS_INQ_REFRESH:
2752 			AHC_SET_DV_STATE(ahc, targ,
2753 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2754 			break;
2755 		default:
2756 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2757 			break;
2758 		}
2759 		break;
2760 
2761 	case AHC_DV_STATE_REBD:
2762 		switch (status & SS_MASK) {
2763 		case SS_NOP:
2764 		{
2765 			uint32_t echo_size;
2766 
2767 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_WEB);
2768 			echo_size = scsi_3btoul(&targ->dv_buffer[1]);
2769 			echo_size &= 0x1FFF;
2770 #ifdef AHC_DEBUG
2771 			if (ahc_debug & AHC_SHOW_DV) {
2772 				ahc_print_devinfo(ahc, devinfo);
2773 				printf("Echo buffer size= %d\n", echo_size);
2774 			}
2775 #endif
2776 			if (echo_size == 0) {
2777 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2778 				break;
2779 			}
2780 
2781 			/* Generate the buffer pattern */
2782 			targ->dv_echo_size = echo_size;
2783 			ahc_linux_generate_dv_pattern(targ);
2784 			/*
2785 			 * Setup initial negotiation values.
2786 			 */
2787 			ahc_linux_filter_inquiry(ahc, devinfo);
2788 			break;
2789 		}
2790 		case SS_INQ_REFRESH:
2791 			AHC_SET_DV_STATE(ahc, targ,
2792 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2793 			break;
2794 		case SS_RETRY:
2795 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2796 			if (ahc_cmd_get_transaction_status(cmd)
2797 			 == CAM_REQUEUE_REQ)
2798 				targ->dv_state_retry--;
2799 			if (targ->dv_state_retry <= 10)
2800 				break;
2801 #ifdef AHC_DEBUG
2802 			if (ahc_debug & AHC_SHOW_DV) {
2803 				ahc_print_devinfo(ahc, devinfo);
2804 				printf("DV REBD reties exhausted\n");
2805 			}
2806 #endif
2807 			/* FALLTHROUGH */
2808 		case SS_FATAL:
2809 		default:
2810 			/*
2811 			 * Setup initial negotiation values
2812 			 * and try level 1 DV.
2813 			 */
2814 			ahc_linux_filter_inquiry(ahc, devinfo);
2815 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_INQ_VERIFY);
2816 			targ->dv_echo_size = 0;
2817 			break;
2818 		}
2819 		break;
2820 
2821 	case AHC_DV_STATE_WEB:
2822 		switch (status & SS_MASK) {
2823 		case SS_NOP:
2824 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_REB);
2825 			break;
2826 		case SS_INQ_REFRESH:
2827 			AHC_SET_DV_STATE(ahc, targ,
2828 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2829 			break;
2830 		case SS_RETRY:
2831 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2832 			if (ahc_cmd_get_transaction_status(cmd)
2833 			 == CAM_REQUEUE_REQ) {
2834 				targ->dv_state_retry--;
2835 			} else if ((status & SSQ_FALLBACK) != 0) {
2836 				if (ahc_linux_fallback(ahc, devinfo) != 0) {
2837 					AHC_SET_DV_STATE(ahc, targ,
2838 							 AHC_DV_STATE_EXIT);
2839 					break;
2840 				}
2841 				/*
2842 				 * Do not count "falling back"
2843 				 * against our retries.
2844 				 */
2845 				targ->dv_state_retry = 0;
2846 			}
2847 			if (targ->dv_state_retry <= 10)
2848 				break;
2849 			/* FALLTHROUGH */
2850 #ifdef AHC_DEBUG
2851 			if (ahc_debug & AHC_SHOW_DV) {
2852 				ahc_print_devinfo(ahc, devinfo);
2853 				printf("DV WEB reties exhausted\n");
2854 			}
2855 #endif
2856 		default:
2857 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2858 			break;
2859 		}
2860 		break;
2861 
2862 	case AHC_DV_STATE_REB:
2863 		switch (status & SS_MASK) {
2864 		case SS_NOP:
2865 			if (memcmp(targ->dv_buffer, targ->dv_buffer1,
2866 				   targ->dv_echo_size) != 0) {
2867 				if (ahc_linux_fallback(ahc, devinfo) != 0)
2868 					AHC_SET_DV_STATE(ahc, targ,
2869 							 AHC_DV_STATE_EXIT);
2870 				else
2871 					AHC_SET_DV_STATE(ahc, targ,
2872 							 AHC_DV_STATE_WEB);
2873 				break;
2874 			}
2875 
2876 			if (targ->dv_buffer != NULL) {
2877 				free(targ->dv_buffer, M_DEVBUF);
2878 				targ->dv_buffer = NULL;
2879 			}
2880 			if (targ->dv_buffer1 != NULL) {
2881 				free(targ->dv_buffer1, M_DEVBUF);
2882 				targ->dv_buffer1 = NULL;
2883 			}
2884 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2885 			break;
2886 		case SS_INQ_REFRESH:
2887 			AHC_SET_DV_STATE(ahc, targ,
2888 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2889 			break;
2890 		case SS_RETRY:
2891 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2892 			if (ahc_cmd_get_transaction_status(cmd)
2893 			 == CAM_REQUEUE_REQ) {
2894 				targ->dv_state_retry--;
2895 			} else if ((status & SSQ_FALLBACK) != 0) {
2896 				if (ahc_linux_fallback(ahc, devinfo) != 0) {
2897 					AHC_SET_DV_STATE(ahc, targ,
2898 							 AHC_DV_STATE_EXIT);
2899 					break;
2900 				}
2901 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_WEB);
2902 			}
2903 			if (targ->dv_state_retry <= 10) {
2904 				if ((status & (SSQ_DELAY_RANDOM|SSQ_DELAY))!= 0)
2905 					msleep(ahc->our_id*1000/10);
2906 				break;
2907 			}
2908 #ifdef AHC_DEBUG
2909 			if (ahc_debug & AHC_SHOW_DV) {
2910 				ahc_print_devinfo(ahc, devinfo);
2911 				printf("DV REB reties exhausted\n");
2912 			}
2913 #endif
2914 			/* FALLTHROUGH */
2915 		default:
2916 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2917 			break;
2918 		}
2919 		break;
2920 
2921 	case AHC_DV_STATE_SU:
2922 		switch (status & SS_MASK) {
2923 		case SS_NOP:
2924 		case SS_INQ_REFRESH:
2925 			AHC_SET_DV_STATE(ahc, targ,
2926 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2927 			break;
2928 		default:
2929 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2930 			break;
2931 		}
2932 		break;
2933 
2934 	case AHC_DV_STATE_BUSY:
2935 		switch (status & SS_MASK) {
2936 		case SS_NOP:
2937 		case SS_INQ_REFRESH:
2938 			AHC_SET_DV_STATE(ahc, targ,
2939 					 AHC_DV_STATE_INQ_SHORT_ASYNC);
2940 			break;
2941 		case SS_TUR:
2942 		case SS_RETRY:
2943 			AHC_SET_DV_STATE(ahc, targ, targ->dv_state);
2944 			if (ahc_cmd_get_transaction_status(cmd)
2945 			 == CAM_REQUEUE_REQ) {
2946 				targ->dv_state_retry--;
2947 			} else if (targ->dv_state_retry < 60) {
2948 				if ((status & SSQ_DELAY) != 0)
2949 					ssleep(1);
2950 			} else {
2951 #ifdef AHC_DEBUG
2952 				if (ahc_debug & AHC_SHOW_DV) {
2953 					ahc_print_devinfo(ahc, devinfo);
2954 					printf("DV BUSY reties exhausted\n");
2955 				}
2956 #endif
2957 				AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2958 			}
2959 			break;
2960 		default:
2961 			AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2962 			break;
2963 		}
2964 		break;
2965 
2966 	default:
2967 		printf("%s: Invalid DV completion state %d\n", ahc_name(ahc),
2968 		       targ->dv_state);
2969 		AHC_SET_DV_STATE(ahc, targ, AHC_DV_STATE_EXIT);
2970 		break;
2971 	}
2972 }
2973 
2974 static void
2975 ahc_linux_dv_fill_cmd(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
2976 		      struct ahc_devinfo *devinfo)
2977 {
2978 	memset(cmd, 0, sizeof(struct scsi_cmnd));
2979 	cmd->device = ahc->platform_data->dv_scsi_dev;
2980 	cmd->scsi_done = ahc_linux_dv_complete;
2981 }
2982 
2983 /*
2984  * Synthesize an inquiry command.  On the return trip, it'll be
2985  * sniffed and the device transfer settings set for us.
2986  */
2987 static void
2988 ahc_linux_dv_inq(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
2989 		 struct ahc_devinfo *devinfo, struct ahc_linux_target *targ,
2990 		 u_int request_length)
2991 {
2992 
2993 #ifdef AHC_DEBUG
2994 	if (ahc_debug & AHC_SHOW_DV) {
2995 		ahc_print_devinfo(ahc, devinfo);
2996 		printf("Sending INQ\n");
2997 	}
2998 #endif
2999 	if (targ->inq_data == NULL)
3000 		targ->inq_data = malloc(AHC_LINUX_DV_INQ_LEN,
3001 					M_DEVBUF, M_WAITOK);
3002 	if (targ->dv_state > AHC_DV_STATE_INQ_ASYNC) {
3003 		if (targ->dv_buffer != NULL)
3004 			free(targ->dv_buffer, M_DEVBUF);
3005 		targ->dv_buffer = malloc(AHC_LINUX_DV_INQ_LEN,
3006 					 M_DEVBUF, M_WAITOK);
3007 	}
3008 
3009 	ahc_linux_dv_fill_cmd(ahc, cmd, devinfo);
3010 	cmd->sc_data_direction = SCSI_DATA_READ;
3011 	cmd->cmd_len = 6;
3012 	cmd->cmnd[0] = INQUIRY;
3013 	cmd->cmnd[4] = request_length;
3014 	cmd->request_bufflen = request_length;
3015 	if (targ->dv_state > AHC_DV_STATE_INQ_ASYNC)
3016 		cmd->request_buffer = targ->dv_buffer;
3017 	else
3018 		cmd->request_buffer = targ->inq_data;
3019 	memset(cmd->request_buffer, 0, AHC_LINUX_DV_INQ_LEN);
3020 }
3021 
3022 static void
3023 ahc_linux_dv_tur(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
3024 		 struct ahc_devinfo *devinfo)
3025 {
3026 
3027 #ifdef AHC_DEBUG
3028 	if (ahc_debug & AHC_SHOW_DV) {
3029 		ahc_print_devinfo(ahc, devinfo);
3030 		printf("Sending TUR\n");
3031 	}
3032 #endif
3033 	/* Do a TUR to clear out any non-fatal transitional state */
3034 	ahc_linux_dv_fill_cmd(ahc, cmd, devinfo);
3035 	cmd->sc_data_direction = SCSI_DATA_NONE;
3036 	cmd->cmd_len = 6;
3037 	cmd->cmnd[0] = TEST_UNIT_READY;
3038 }
3039 
3040 #define AHC_REBD_LEN 4
3041 
3042 static void
3043 ahc_linux_dv_rebd(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
3044 		 struct ahc_devinfo *devinfo, struct ahc_linux_target *targ)
3045 {
3046 
3047 #ifdef AHC_DEBUG
3048 	if (ahc_debug & AHC_SHOW_DV) {
3049 		ahc_print_devinfo(ahc, devinfo);
3050 		printf("Sending REBD\n");
3051 	}
3052 #endif
3053 	if (targ->dv_buffer != NULL)
3054 		free(targ->dv_buffer, M_DEVBUF);
3055 	targ->dv_buffer = malloc(AHC_REBD_LEN, M_DEVBUF, M_WAITOK);
3056 	ahc_linux_dv_fill_cmd(ahc, cmd, devinfo);
3057 	cmd->sc_data_direction = SCSI_DATA_READ;
3058 	cmd->cmd_len = 10;
3059 	cmd->cmnd[0] = READ_BUFFER;
3060 	cmd->cmnd[1] = 0x0b;
3061 	scsi_ulto3b(AHC_REBD_LEN, &cmd->cmnd[6]);
3062 	cmd->request_bufflen = AHC_REBD_LEN;
3063 	cmd->underflow = cmd->request_bufflen;
3064 	cmd->request_buffer = targ->dv_buffer;
3065 }
3066 
3067 static void
3068 ahc_linux_dv_web(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
3069 		 struct ahc_devinfo *devinfo, struct ahc_linux_target *targ)
3070 {
3071 
3072 #ifdef AHC_DEBUG
3073 	if (ahc_debug & AHC_SHOW_DV) {
3074 		ahc_print_devinfo(ahc, devinfo);
3075 		printf("Sending WEB\n");
3076 	}
3077 #endif
3078 	ahc_linux_dv_fill_cmd(ahc, cmd, devinfo);
3079 	cmd->sc_data_direction = SCSI_DATA_WRITE;
3080 	cmd->cmd_len = 10;
3081 	cmd->cmnd[0] = WRITE_BUFFER;
3082 	cmd->cmnd[1] = 0x0a;
3083 	scsi_ulto3b(targ->dv_echo_size, &cmd->cmnd[6]);
3084 	cmd->request_bufflen = targ->dv_echo_size;
3085 	cmd->underflow = cmd->request_bufflen;
3086 	cmd->request_buffer = targ->dv_buffer;
3087 }
3088 
3089 static void
3090 ahc_linux_dv_reb(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
3091 		 struct ahc_devinfo *devinfo, struct ahc_linux_target *targ)
3092 {
3093 
3094 #ifdef AHC_DEBUG
3095 	if (ahc_debug & AHC_SHOW_DV) {
3096 		ahc_print_devinfo(ahc, devinfo);
3097 		printf("Sending REB\n");
3098 	}
3099 #endif
3100 	ahc_linux_dv_fill_cmd(ahc, cmd, devinfo);
3101 	cmd->sc_data_direction = SCSI_DATA_READ;
3102 	cmd->cmd_len = 10;
3103 	cmd->cmnd[0] = READ_BUFFER;
3104 	cmd->cmnd[1] = 0x0a;
3105 	scsi_ulto3b(targ->dv_echo_size, &cmd->cmnd[6]);
3106 	cmd->request_bufflen = targ->dv_echo_size;
3107 	cmd->underflow = cmd->request_bufflen;
3108 	cmd->request_buffer = targ->dv_buffer1;
3109 }
3110 
3111 static void
3112 ahc_linux_dv_su(struct ahc_softc *ahc, struct scsi_cmnd *cmd,
3113 		struct ahc_devinfo *devinfo,
3114 		struct ahc_linux_target *targ)
3115 {
3116 	u_int le;
3117 
3118 	le = SID_IS_REMOVABLE(targ->inq_data) ? SSS_LOEJ : 0;
3119 
3120 #ifdef AHC_DEBUG
3121 	if (ahc_debug & AHC_SHOW_DV) {
3122 		ahc_print_devinfo(ahc, devinfo);
3123 		printf("Sending SU\n");
3124 	}
3125 #endif
3126 	ahc_linux_dv_fill_cmd(ahc, cmd, devinfo);
3127 	cmd->sc_data_direction = SCSI_DATA_NONE;
3128 	cmd->cmd_len = 6;
3129 	cmd->cmnd[0] = START_STOP_UNIT;
3130 	cmd->cmnd[4] = le | SSS_START;
3131 }
3132 
3133 static int
3134 ahc_linux_fallback(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
3135 {
3136 	struct	ahc_linux_target *targ;
3137 	struct	ahc_initiator_tinfo *tinfo;
3138 	struct	ahc_transinfo *goal;
3139 	struct	ahc_tmode_tstate *tstate;
3140 	struct	ahc_syncrate *syncrate;
3141 	u_long	s;
3142 	u_int	width;
3143 	u_int	period;
3144 	u_int	offset;
3145 	u_int	ppr_options;
3146 	u_int	cur_speed;
3147 	u_int	wide_speed;
3148 	u_int	narrow_speed;
3149 	u_int	fallback_speed;
3150 
3151 #ifdef AHC_DEBUG
3152 	if (ahc_debug & AHC_SHOW_DV) {
3153 		ahc_print_devinfo(ahc, devinfo);
3154 		printf("Trying to fallback\n");
3155 	}
3156 #endif
3157 	ahc_lock(ahc, &s);
3158 	targ = ahc->platform_data->targets[devinfo->target_offset];
3159 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel,
3160 				    devinfo->our_scsiid,
3161 				    devinfo->target, &tstate);
3162 	goal = &tinfo->goal;
3163 	width = goal->width;
3164 	period = goal->period;
3165 	offset = goal->offset;
3166 	ppr_options = goal->ppr_options;
3167 	if (offset == 0)
3168 		period = AHC_ASYNC_XFER_PERIOD;
3169 	if (targ->dv_next_narrow_period == 0)
3170 		targ->dv_next_narrow_period = MAX(period, AHC_SYNCRATE_ULTRA2);
3171 	if (targ->dv_next_wide_period == 0)
3172 		targ->dv_next_wide_period = period;
3173 	if (targ->dv_max_width == 0)
3174 		targ->dv_max_width = width;
3175 	if (targ->dv_max_ppr_options == 0)
3176 		targ->dv_max_ppr_options = ppr_options;
3177 	if (targ->dv_last_ppr_options == 0)
3178 		targ->dv_last_ppr_options = ppr_options;
3179 
3180 	cur_speed = aic_calc_speed(width, period, offset, AHC_SYNCRATE_MIN);
3181 	wide_speed = aic_calc_speed(MSG_EXT_WDTR_BUS_16_BIT,
3182 					  targ->dv_next_wide_period,
3183 					  MAX_OFFSET,
3184 					  AHC_SYNCRATE_MIN);
3185 	narrow_speed = aic_calc_speed(MSG_EXT_WDTR_BUS_8_BIT,
3186 					    targ->dv_next_narrow_period,
3187 					    MAX_OFFSET,
3188 					    AHC_SYNCRATE_MIN);
3189 	fallback_speed = aic_calc_speed(width, period+1, offset,
3190 					AHC_SYNCRATE_MIN);
3191 #ifdef AHC_DEBUG
3192 	if (ahc_debug & AHC_SHOW_DV) {
3193 		printf("cur_speed= %d, wide_speed= %d, narrow_speed= %d, "
3194 		       "fallback_speed= %d\n", cur_speed, wide_speed,
3195 		       narrow_speed, fallback_speed);
3196 	}
3197 #endif
3198 
3199 	if (cur_speed > 160000) {
3200 		/*
3201 		 * Paced/DT/IU_REQ only transfer speeds.  All we
3202 		 * can do is fallback in terms of syncrate.
3203 		 */
3204 		period++;
3205 	} else if (cur_speed > 80000) {
3206 		if ((ppr_options & MSG_EXT_PPR_IU_REQ) != 0) {
3207 			/*
3208 			 * Try without IU_REQ as it may be confusing
3209 			 * an expander.
3210 			 */
3211 			ppr_options &= ~MSG_EXT_PPR_IU_REQ;
3212 		} else {
3213 			/*
3214 			 * Paced/DT only transfer speeds.  All we
3215 			 * can do is fallback in terms of syncrate.
3216 			 */
3217 			period++;
3218 			ppr_options = targ->dv_max_ppr_options;
3219 		}
3220 	} else if (cur_speed > 3300) {
3221 
3222 		/*
3223 		 * In this range we the following
3224 		 * options ordered from highest to
3225 		 * lowest desireability:
3226 		 *
3227 		 * o Wide/DT
3228 		 * o Wide/non-DT
3229 		 * o Narrow at a potentally higher sync rate.
3230 		 *
3231 		 * All modes are tested with and without IU_REQ
3232 		 * set since using IUs may confuse an expander.
3233 		 */
3234 		if ((ppr_options & MSG_EXT_PPR_IU_REQ) != 0) {
3235 
3236 			ppr_options &= ~MSG_EXT_PPR_IU_REQ;
3237 		} else if ((ppr_options & MSG_EXT_PPR_DT_REQ) != 0) {
3238 			/*
3239 			 * Try going non-DT.
3240 			 */
3241 			ppr_options = targ->dv_max_ppr_options;
3242 			ppr_options &= ~MSG_EXT_PPR_DT_REQ;
3243 		} else if (targ->dv_last_ppr_options != 0) {
3244 			/*
3245 			 * Try without QAS or any other PPR options.
3246 			 * We may need a non-PPR message to work with
3247 			 * an expander.  We look at the "last PPR options"
3248 			 * so we will perform this fallback even if the
3249 			 * target responded to our PPR negotiation with
3250 			 * no option bits set.
3251 			 */
3252 			ppr_options = 0;
3253 		} else if (width == MSG_EXT_WDTR_BUS_16_BIT) {
3254 			/*
3255 			 * If the next narrow speed is greater than
3256 			 * the next wide speed, fallback to narrow.
3257 			 * Otherwise fallback to the next DT/Wide setting.
3258 			 * The narrow async speed will always be smaller
3259 			 * than the wide async speed, so handle this case
3260 			 * specifically.
3261 			 */
3262 			ppr_options = targ->dv_max_ppr_options;
3263 			if (narrow_speed > fallback_speed
3264 			 || period >= AHC_ASYNC_XFER_PERIOD) {
3265 				targ->dv_next_wide_period = period+1;
3266 				width = MSG_EXT_WDTR_BUS_8_BIT;
3267 				period = targ->dv_next_narrow_period;
3268 			} else {
3269 				period++;
3270 			}
3271 		} else if ((ahc->features & AHC_WIDE) != 0
3272 			&& targ->dv_max_width != 0
3273 			&& wide_speed >= fallback_speed
3274 			&& (targ->dv_next_wide_period <= AHC_ASYNC_XFER_PERIOD
3275 			 || period >= AHC_ASYNC_XFER_PERIOD)) {
3276 
3277 			/*
3278 			 * We are narrow.  Try falling back
3279 			 * to the next wide speed with
3280 			 * all supported ppr options set.
3281 			 */
3282 			targ->dv_next_narrow_period = period+1;
3283 			width = MSG_EXT_WDTR_BUS_16_BIT;
3284 			period = targ->dv_next_wide_period;
3285 			ppr_options = targ->dv_max_ppr_options;
3286 		} else {
3287 			/* Only narrow fallback is allowed. */
3288 			period++;
3289 			ppr_options = targ->dv_max_ppr_options;
3290 		}
3291 	} else {
3292 		ahc_unlock(ahc, &s);
3293 		return (-1);
3294 	}
3295 	offset = MAX_OFFSET;
3296 	syncrate = ahc_find_syncrate(ahc, &period, &ppr_options,
3297 				     AHC_SYNCRATE_DT);
3298 	ahc_set_width(ahc, devinfo, width, AHC_TRANS_GOAL, FALSE);
3299 	if (period == 0) {
3300 		period = 0;
3301 		offset = 0;
3302 		ppr_options = 0;
3303 		if (width == MSG_EXT_WDTR_BUS_8_BIT)
3304 			targ->dv_next_narrow_period = AHC_ASYNC_XFER_PERIOD;
3305 		else
3306 			targ->dv_next_wide_period = AHC_ASYNC_XFER_PERIOD;
3307 	}
3308 	ahc_set_syncrate(ahc, devinfo, syncrate, period, offset,
3309 			 ppr_options, AHC_TRANS_GOAL, FALSE);
3310 	targ->dv_last_ppr_options = ppr_options;
3311 	ahc_unlock(ahc, &s);
3312 	return (0);
3313 }
3314 
3315 static void
3316 ahc_linux_dv_timeout(struct scsi_cmnd *cmd)
3317 {
3318 	struct	ahc_softc *ahc;
3319 	struct	scb *scb;
3320 	u_long	flags;
3321 
3322 	ahc = *((struct ahc_softc **)cmd->device->host->hostdata);
3323 	ahc_lock(ahc, &flags);
3324 
3325 #ifdef AHC_DEBUG
3326 	if (ahc_debug & AHC_SHOW_DV) {
3327 		printf("%s: Timeout while doing DV command %x.\n",
3328 		       ahc_name(ahc), cmd->cmnd[0]);
3329 		ahc_dump_card_state(ahc);
3330 	}
3331 #endif
3332 
3333 	/*
3334 	 * Guard against "done race".  No action is
3335 	 * required if we just completed.
3336 	 */
3337 	if ((scb = (struct scb *)cmd->host_scribble) == NULL) {
3338 		ahc_unlock(ahc, &flags);
3339 		return;
3340 	}
3341 
3342 	/*
3343 	 * Command has not completed.  Mark this
3344 	 * SCB as having failing status prior to
3345 	 * resetting the bus, so we get the correct
3346 	 * error code.
3347 	 */
3348 	if ((scb->flags & SCB_SENSE) != 0)
3349 		ahc_set_transaction_status(scb, CAM_AUTOSENSE_FAIL);
3350 	else
3351 		ahc_set_transaction_status(scb, CAM_CMD_TIMEOUT);
3352 	ahc_reset_channel(ahc, cmd->device->channel + 'A', /*initiate*/TRUE);
3353 
3354 	/*
3355 	 * Add a minimal bus settle delay for devices that are slow to
3356 	 * respond after bus resets.
3357 	 */
3358 	ahc_linux_freeze_simq(ahc);
3359 	init_timer(&ahc->platform_data->reset_timer);
3360 	ahc->platform_data->reset_timer.data = (u_long)ahc;
3361 	ahc->platform_data->reset_timer.expires = jiffies + HZ / 2;
3362 	ahc->platform_data->reset_timer.function =
3363 	    (ahc_linux_callback_t *)ahc_linux_release_simq;
3364 	add_timer(&ahc->platform_data->reset_timer);
3365 	if (ahc_linux_next_device_to_run(ahc) != NULL)
3366 		ahc_schedule_runq(ahc);
3367 	ahc_linux_run_complete_queue(ahc);
3368 	ahc_unlock(ahc, &flags);
3369 }
3370 
3371 static void
3372 ahc_linux_dv_complete(struct scsi_cmnd *cmd)
3373 {
3374 	struct ahc_softc *ahc;
3375 
3376 	ahc = *((struct ahc_softc **)cmd->device->host->hostdata);
3377 
3378 	/* Delete the DV timer before it goes off! */
3379 	scsi_delete_timer(cmd);
3380 
3381 #ifdef AHC_DEBUG
3382 	if (ahc_debug & AHC_SHOW_DV)
3383 		printf("%s:%d:%d: Command completed, status= 0x%x\n",
3384 		       ahc_name(ahc), cmd->device->channel,
3385 		       cmd->device->id, cmd->result);
3386 #endif
3387 
3388 	/* Wake up the state machine */
3389 	up(&ahc->platform_data->dv_cmd_sem);
3390 }
3391 
3392 static void
3393 ahc_linux_generate_dv_pattern(struct ahc_linux_target *targ)
3394 {
3395 	uint16_t b;
3396 	u_int	 i;
3397 	u_int	 j;
3398 
3399 	if (targ->dv_buffer != NULL)
3400 		free(targ->dv_buffer, M_DEVBUF);
3401 	targ->dv_buffer = malloc(targ->dv_echo_size, M_DEVBUF, M_WAITOK);
3402 	if (targ->dv_buffer1 != NULL)
3403 		free(targ->dv_buffer1, M_DEVBUF);
3404 	targ->dv_buffer1 = malloc(targ->dv_echo_size, M_DEVBUF, M_WAITOK);
3405 
3406 	i = 0;
3407 	b = 0x0001;
3408 	for (j = 0 ; i < targ->dv_echo_size; j++) {
3409 		if (j < 32) {
3410 			/*
3411 			 * 32bytes of sequential numbers.
3412 			 */
3413 			targ->dv_buffer[i++] = j & 0xff;
3414 		} else if (j < 48) {
3415 			/*
3416 			 * 32bytes of repeating 0x0000, 0xffff.
3417 			 */
3418 			targ->dv_buffer[i++] = (j & 0x02) ? 0xff : 0x00;
3419 		} else if (j < 64) {
3420 			/*
3421 			 * 32bytes of repeating 0x5555, 0xaaaa.
3422 			 */
3423 			targ->dv_buffer[i++] = (j & 0x02) ? 0xaa : 0x55;
3424 		} else {
3425 			/*
3426 			 * Remaining buffer is filled with a repeating
3427 			 * patter of:
3428 			 *
3429 			 *	 0xffff
3430 			 *	~0x0001 << shifted once in each loop.
3431 			 */
3432 			if (j & 0x02) {
3433 				if (j & 0x01) {
3434 					targ->dv_buffer[i++] = ~(b >> 8) & 0xff;
3435 					b <<= 1;
3436 					if (b == 0x0000)
3437 						b = 0x0001;
3438 				} else {
3439 					targ->dv_buffer[i++] = (~b & 0xff);
3440 				}
3441 			} else {
3442 				targ->dv_buffer[i++] = 0xff;
3443 			}
3444 		}
3445 	}
3446 }
3447 
3448 static u_int
3449 ahc_linux_user_tagdepth(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
3450 {
3451 	static int warned_user;
3452 	u_int tags;
3453 
3454 	tags = 0;
3455 	if ((ahc->user_discenable & devinfo->target_mask) != 0) {
3456 		if (ahc->unit >= NUM_ELEMENTS(aic7xxx_tag_info)) {
3457 			if (warned_user == 0) {
3458 
3459 				printf(KERN_WARNING
3460 "aic7xxx: WARNING: Insufficient tag_info instances\n"
3461 "aic7xxx: for installed controllers. Using defaults\n"
3462 "aic7xxx: Please update the aic7xxx_tag_info array in\n"
3463 "aic7xxx: the aic7xxx_osm..c source file.\n");
3464 				warned_user++;
3465 			}
3466 			tags = AHC_MAX_QUEUE;
3467 		} else {
3468 			adapter_tag_info_t *tag_info;
3469 
3470 			tag_info = &aic7xxx_tag_info[ahc->unit];
3471 			tags = tag_info->tag_commands[devinfo->target_offset];
3472 			if (tags > AHC_MAX_QUEUE)
3473 				tags = AHC_MAX_QUEUE;
3474 		}
3475 	}
3476 	return (tags);
3477 }
3478 
3479 static u_int
3480 ahc_linux_user_dv_setting(struct ahc_softc *ahc)
3481 {
3482 	static int warned_user;
3483 	int dv;
3484 
3485 	if (ahc->unit >= NUM_ELEMENTS(aic7xxx_dv_settings)) {
3486 		if (warned_user == 0) {
3487 
3488 			printf(KERN_WARNING
3489 "aic7xxx: WARNING: Insufficient dv settings instances\n"
3490 "aic7xxx: for installed controllers. Using defaults\n"
3491 "aic7xxx: Please update the aic7xxx_dv_settings array\n"
3492 "aic7xxx: in the aic7xxx_osm.c source file.\n");
3493 			warned_user++;
3494 		}
3495 		dv = -1;
3496 	} else {
3497 
3498 		dv = aic7xxx_dv_settings[ahc->unit];
3499 	}
3500 
3501 	if (dv < 0) {
3502 		u_long s;
3503 
3504 		/*
3505 		 * Apply the default.
3506 		 */
3507 		/*
3508 		 * XXX - Enable DV on non-U160 controllers once it
3509 		 *       has been tested there.
3510 		 */
3511 		ahc_lock(ahc, &s);
3512 		dv = (ahc->features & AHC_DT);
3513 		if (ahc->seep_config != 0
3514 		 && ahc->seep_config->signature >= CFSIGNATURE2)
3515 			dv = (ahc->seep_config->adapter_control & CFENABLEDV);
3516 		ahc_unlock(ahc, &s);
3517 	}
3518 	return (dv);
3519 }
3520 
3521 /*
3522  * Determines the queue depth for a given device.
3523  */
3524 static void
3525 ahc_linux_device_queue_depth(struct ahc_softc *ahc,
3526 			     struct ahc_linux_device *dev)
3527 {
3528 	struct	ahc_devinfo devinfo;
3529 	u_int	tags;
3530 
3531 	ahc_compile_devinfo(&devinfo,
3532 			    dev->target->channel == 0
3533 			  ? ahc->our_id : ahc->our_id_b,
3534 			    dev->target->target, dev->lun,
3535 			    dev->target->channel == 0 ? 'A' : 'B',
3536 			    ROLE_INITIATOR);
3537 	tags = ahc_linux_user_tagdepth(ahc, &devinfo);
3538 	if (tags != 0
3539 	 && dev->scsi_device != NULL
3540 	 && dev->scsi_device->tagged_supported != 0) {
3541 
3542 		ahc_set_tags(ahc, &devinfo, AHC_QUEUE_TAGGED);
3543 		ahc_print_devinfo(ahc, &devinfo);
3544 		printf("Tagged Queuing enabled.  Depth %d\n", tags);
3545 	} else {
3546 		ahc_set_tags(ahc, &devinfo, AHC_QUEUE_NONE);
3547 	}
3548 }
3549 
3550 static void
3551 ahc_linux_run_device_queue(struct ahc_softc *ahc, struct ahc_linux_device *dev)
3552 {
3553 	struct	 ahc_cmd *acmd;
3554 	struct	 scsi_cmnd *cmd;
3555 	struct	 scb *scb;
3556 	struct	 hardware_scb *hscb;
3557 	struct	 ahc_initiator_tinfo *tinfo;
3558 	struct	 ahc_tmode_tstate *tstate;
3559 	uint16_t mask;
3560 
3561 	if ((dev->flags & AHC_DEV_ON_RUN_LIST) != 0)
3562 		panic("running device on run list");
3563 
3564 	while ((acmd = TAILQ_FIRST(&dev->busyq)) != NULL
3565 	    && dev->openings > 0 && dev->qfrozen == 0) {
3566 
3567 		/*
3568 		 * Schedule us to run later.  The only reason we are not
3569 		 * running is because the whole controller Q is frozen.
3570 		 */
3571 		if (ahc->platform_data->qfrozen != 0
3572 	 	 && AHC_DV_SIMQ_FROZEN(ahc) == 0) {
3573 			TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq,
3574 					  dev, links);
3575 			dev->flags |= AHC_DEV_ON_RUN_LIST;
3576 			return;
3577 		}
3578 		/*
3579 		 * Get an scb to use.
3580 		 */
3581 		if ((scb = ahc_get_scb(ahc)) == NULL) {
3582 			TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq,
3583 					 dev, links);
3584 			dev->flags |= AHC_DEV_ON_RUN_LIST;
3585 			ahc->flags |= AHC_RESOURCE_SHORTAGE;
3586 			return;
3587 		}
3588 		TAILQ_REMOVE(&dev->busyq, acmd, acmd_links.tqe);
3589 		cmd = &acmd_scsi_cmd(acmd);
3590 		scb->io_ctx = cmd;
3591 		scb->platform_data->dev = dev;
3592 		hscb = scb->hscb;
3593 		cmd->host_scribble = (char *)scb;
3594 
3595 		/*
3596 		 * Fill out basics of the HSCB.
3597 		 */
3598 		hscb->control = 0;
3599 		hscb->scsiid = BUILD_SCSIID(ahc, cmd);
3600 		hscb->lun = cmd->device->lun;
3601 		mask = SCB_GET_TARGET_MASK(ahc, scb);
3602 		tinfo = ahc_fetch_transinfo(ahc, SCB_GET_CHANNEL(ahc, scb),
3603 					    SCB_GET_OUR_ID(scb),
3604 					    SCB_GET_TARGET(ahc, scb), &tstate);
3605 		hscb->scsirate = tinfo->scsirate;
3606 		hscb->scsioffset = tinfo->curr.offset;
3607 		if ((tstate->ultraenb & mask) != 0)
3608 			hscb->control |= ULTRAENB;
3609 
3610 		if ((ahc->user_discenable & mask) != 0)
3611 			hscb->control |= DISCENB;
3612 
3613 	 	if (AHC_DV_CMD(cmd) != 0)
3614 			scb->flags |= SCB_SILENT;
3615 
3616 		if ((tstate->auto_negotiate & mask) != 0) {
3617 			scb->flags |= SCB_AUTO_NEGOTIATE;
3618 			scb->hscb->control |= MK_MESSAGE;
3619 		}
3620 
3621 		if ((dev->flags & (AHC_DEV_Q_TAGGED|AHC_DEV_Q_BASIC)) != 0) {
3622 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
3623 			int	msg_bytes;
3624 			uint8_t tag_msgs[2];
3625 
3626 			msg_bytes = scsi_populate_tag_msg(cmd, tag_msgs);
3627 			if (msg_bytes && tag_msgs[0] != MSG_SIMPLE_TASK) {
3628 				hscb->control |= tag_msgs[0];
3629 				if (tag_msgs[0] == MSG_ORDERED_TASK)
3630 					dev->commands_since_idle_or_otag = 0;
3631 			} else
3632 #endif
3633 			if (dev->commands_since_idle_or_otag == AHC_OTAG_THRESH
3634 			 && (dev->flags & AHC_DEV_Q_TAGGED) != 0) {
3635 				hscb->control |= MSG_ORDERED_TASK;
3636 				dev->commands_since_idle_or_otag = 0;
3637 			} else {
3638 				hscb->control |= MSG_SIMPLE_TASK;
3639 			}
3640 		}
3641 
3642 		hscb->cdb_len = cmd->cmd_len;
3643 		if (hscb->cdb_len <= 12) {
3644 			memcpy(hscb->shared_data.cdb, cmd->cmnd, hscb->cdb_len);
3645 		} else {
3646 			memcpy(hscb->cdb32, cmd->cmnd, hscb->cdb_len);
3647 			scb->flags |= SCB_CDB32_PTR;
3648 		}
3649 
3650 		scb->platform_data->xfer_len = 0;
3651 		ahc_set_residual(scb, 0);
3652 		ahc_set_sense_residual(scb, 0);
3653 		scb->sg_count = 0;
3654 		if (cmd->use_sg != 0) {
3655 			struct	ahc_dma_seg *sg;
3656 			struct	scatterlist *cur_seg;
3657 			struct	scatterlist *end_seg;
3658 			int	nseg;
3659 
3660 			cur_seg = (struct scatterlist *)cmd->request_buffer;
3661 			nseg = pci_map_sg(ahc->dev_softc, cur_seg, cmd->use_sg,
3662 			    scsi_to_pci_dma_dir(cmd->sc_data_direction));
3663 			end_seg = cur_seg + nseg;
3664 			/* Copy the segments into the SG list. */
3665 			sg = scb->sg_list;
3666 			/*
3667 			 * The sg_count may be larger than nseg if
3668 			 * a transfer crosses a 32bit page.
3669 			 */
3670 			while (cur_seg < end_seg) {
3671 				dma_addr_t addr;
3672 				bus_size_t len;
3673 				int consumed;
3674 
3675 				addr = sg_dma_address(cur_seg);
3676 				len = sg_dma_len(cur_seg);
3677 				consumed = ahc_linux_map_seg(ahc, scb,
3678 							     sg, addr, len);
3679 				sg += consumed;
3680 				scb->sg_count += consumed;
3681 				cur_seg++;
3682 			}
3683 			sg--;
3684 			sg->len |= ahc_htole32(AHC_DMA_LAST_SEG);
3685 
3686 			/*
3687 			 * Reset the sg list pointer.
3688 			 */
3689 			scb->hscb->sgptr =
3690 			    ahc_htole32(scb->sg_list_phys | SG_FULL_RESID);
3691 
3692 			/*
3693 			 * Copy the first SG into the "current"
3694 			 * data pointer area.
3695 			 */
3696 			scb->hscb->dataptr = scb->sg_list->addr;
3697 			scb->hscb->datacnt = scb->sg_list->len;
3698 		} else if (cmd->request_bufflen != 0) {
3699 			struct	 ahc_dma_seg *sg;
3700 			dma_addr_t addr;
3701 
3702 			sg = scb->sg_list;
3703 			addr = pci_map_single(ahc->dev_softc,
3704 			       cmd->request_buffer,
3705 			       cmd->request_bufflen,
3706 			       scsi_to_pci_dma_dir(cmd->sc_data_direction));
3707 			scb->platform_data->buf_busaddr = addr;
3708 			scb->sg_count = ahc_linux_map_seg(ahc, scb,
3709 							  sg, addr,
3710 							  cmd->request_bufflen);
3711 			sg->len |= ahc_htole32(AHC_DMA_LAST_SEG);
3712 
3713 			/*
3714 			 * Reset the sg list pointer.
3715 			 */
3716 			scb->hscb->sgptr =
3717 			    ahc_htole32(scb->sg_list_phys | SG_FULL_RESID);
3718 
3719 			/*
3720 			 * Copy the first SG into the "current"
3721 			 * data pointer area.
3722 			 */
3723 			scb->hscb->dataptr = sg->addr;
3724 			scb->hscb->datacnt = sg->len;
3725 		} else {
3726 			scb->hscb->sgptr = ahc_htole32(SG_LIST_NULL);
3727 			scb->hscb->dataptr = 0;
3728 			scb->hscb->datacnt = 0;
3729 			scb->sg_count = 0;
3730 		}
3731 
3732 		ahc_sync_sglist(ahc, scb, BUS_DMASYNC_PREWRITE);
3733 		LIST_INSERT_HEAD(&ahc->pending_scbs, scb, pending_links);
3734 		dev->openings--;
3735 		dev->active++;
3736 		dev->commands_issued++;
3737 		if ((dev->flags & AHC_DEV_PERIODIC_OTAG) != 0)
3738 			dev->commands_since_idle_or_otag++;
3739 
3740 		/*
3741 		 * We only allow one untagged transaction
3742 		 * per target in the initiator role unless
3743 		 * we are storing a full busy target *lun*
3744 		 * table in SCB space.
3745 		 */
3746 		if ((scb->hscb->control & (TARGET_SCB|TAG_ENB)) == 0
3747 		 && (ahc->features & AHC_SCB_BTT) == 0) {
3748 			struct scb_tailq *untagged_q;
3749 			int target_offset;
3750 
3751 			target_offset = SCB_GET_TARGET_OFFSET(ahc, scb);
3752 			untagged_q = &(ahc->untagged_queues[target_offset]);
3753 			TAILQ_INSERT_TAIL(untagged_q, scb, links.tqe);
3754 			scb->flags |= SCB_UNTAGGEDQ;
3755 			if (TAILQ_FIRST(untagged_q) != scb)
3756 				continue;
3757 		}
3758 		scb->flags |= SCB_ACTIVE;
3759 		ahc_queue_scb(ahc, scb);
3760 	}
3761 }
3762 
3763 /*
3764  * SCSI controller interrupt handler.
3765  */
3766 irqreturn_t
3767 ahc_linux_isr(int irq, void *dev_id, struct pt_regs * regs)
3768 {
3769 	struct	ahc_softc *ahc;
3770 	u_long	flags;
3771 	int	ours;
3772 
3773 	ahc = (struct ahc_softc *) dev_id;
3774 	ahc_lock(ahc, &flags);
3775 	ours = ahc_intr(ahc);
3776 	if (ahc_linux_next_device_to_run(ahc) != NULL)
3777 		ahc_schedule_runq(ahc);
3778 	ahc_linux_run_complete_queue(ahc);
3779 	ahc_unlock(ahc, &flags);
3780 	return IRQ_RETVAL(ours);
3781 }
3782 
3783 void
3784 ahc_platform_flushwork(struct ahc_softc *ahc)
3785 {
3786 
3787 	while (ahc_linux_run_complete_queue(ahc) != NULL)
3788 		;
3789 }
3790 
3791 static struct ahc_linux_target*
3792 ahc_linux_alloc_target(struct ahc_softc *ahc, u_int channel, u_int target)
3793 {
3794 	struct ahc_linux_target *targ;
3795 	u_int target_offset;
3796 
3797 	target_offset = target;
3798 	if (channel != 0)
3799 		target_offset += 8;
3800 
3801 	targ = malloc(sizeof(*targ), M_DEVBUG, M_NOWAIT);
3802 	if (targ == NULL)
3803 		return (NULL);
3804 	memset(targ, 0, sizeof(*targ));
3805 	targ->channel = channel;
3806 	targ->target = target;
3807 	targ->ahc = ahc;
3808 	targ->flags = AHC_DV_REQUIRED;
3809 	ahc->platform_data->targets[target_offset] = targ;
3810 	return (targ);
3811 }
3812 
3813 static void
3814 ahc_linux_free_target(struct ahc_softc *ahc, struct ahc_linux_target *targ)
3815 {
3816 	struct ahc_devinfo devinfo;
3817 	struct ahc_initiator_tinfo *tinfo;
3818 	struct ahc_tmode_tstate *tstate;
3819 	u_int our_id;
3820 	u_int target_offset;
3821 	char channel;
3822 
3823 	/*
3824 	 * Force a negotiation to async/narrow on any
3825 	 * future command to this device unless a bus
3826 	 * reset occurs between now and that command.
3827 	 */
3828 	channel = 'A' + targ->channel;
3829 	our_id = ahc->our_id;
3830 	target_offset = targ->target;
3831 	if (targ->channel != 0) {
3832 		target_offset += 8;
3833 		our_id = ahc->our_id_b;
3834 	}
3835 	tinfo = ahc_fetch_transinfo(ahc, channel, our_id,
3836 				    targ->target, &tstate);
3837 	ahc_compile_devinfo(&devinfo, our_id, targ->target, CAM_LUN_WILDCARD,
3838 			    channel, ROLE_INITIATOR);
3839 	ahc_set_syncrate(ahc, &devinfo, NULL, 0, 0, 0,
3840 			 AHC_TRANS_GOAL, /*paused*/FALSE);
3841 	ahc_set_width(ahc, &devinfo, MSG_EXT_WDTR_BUS_8_BIT,
3842 		      AHC_TRANS_GOAL, /*paused*/FALSE);
3843 	ahc_update_neg_request(ahc, &devinfo, tstate, tinfo, AHC_NEG_ALWAYS);
3844 	ahc->platform_data->targets[target_offset] = NULL;
3845 	if (targ->inq_data != NULL)
3846 		free(targ->inq_data, M_DEVBUF);
3847 	if (targ->dv_buffer != NULL)
3848 		free(targ->dv_buffer, M_DEVBUF);
3849 	if (targ->dv_buffer1 != NULL)
3850 		free(targ->dv_buffer1, M_DEVBUF);
3851 	free(targ, M_DEVBUF);
3852 }
3853 
3854 static struct ahc_linux_device*
3855 ahc_linux_alloc_device(struct ahc_softc *ahc,
3856 		 struct ahc_linux_target *targ, u_int lun)
3857 {
3858 	struct ahc_linux_device *dev;
3859 
3860 	dev = malloc(sizeof(*dev), M_DEVBUG, M_NOWAIT);
3861 	if (dev == NULL)
3862 		return (NULL);
3863 	memset(dev, 0, sizeof(*dev));
3864 	init_timer(&dev->timer);
3865 	TAILQ_INIT(&dev->busyq);
3866 	dev->flags = AHC_DEV_UNCONFIGURED;
3867 	dev->lun = lun;
3868 	dev->target = targ;
3869 
3870 	/*
3871 	 * We start out life using untagged
3872 	 * transactions of which we allow one.
3873 	 */
3874 	dev->openings = 1;
3875 
3876 	/*
3877 	 * Set maxtags to 0.  This will be changed if we
3878 	 * later determine that we are dealing with
3879 	 * a tagged queuing capable device.
3880 	 */
3881 	dev->maxtags = 0;
3882 
3883 	targ->refcount++;
3884 	targ->devices[lun] = dev;
3885 	return (dev);
3886 }
3887 
3888 static void
3889 __ahc_linux_free_device(struct ahc_softc *ahc, struct ahc_linux_device *dev)
3890 {
3891 	struct ahc_linux_target *targ;
3892 
3893 	targ = dev->target;
3894 	targ->devices[dev->lun] = NULL;
3895 	free(dev, M_DEVBUF);
3896 	targ->refcount--;
3897 	if (targ->refcount == 0
3898 	 && (targ->flags & AHC_DV_REQUIRED) == 0)
3899 		ahc_linux_free_target(ahc, targ);
3900 }
3901 
3902 static void
3903 ahc_linux_free_device(struct ahc_softc *ahc, struct ahc_linux_device *dev)
3904 {
3905 	del_timer_sync(&dev->timer);
3906 	__ahc_linux_free_device(ahc, dev);
3907 }
3908 
3909 void
3910 ahc_send_async(struct ahc_softc *ahc, char channel,
3911 	       u_int target, u_int lun, ac_code code, void *arg)
3912 {
3913 	switch (code) {
3914 	case AC_TRANSFER_NEG:
3915 	{
3916 		char	buf[80];
3917 		struct	ahc_linux_target *targ;
3918 		struct	info_str info;
3919 		struct	ahc_initiator_tinfo *tinfo;
3920 		struct	ahc_tmode_tstate *tstate;
3921 		int	target_offset;
3922 
3923 		info.buffer = buf;
3924 		info.length = sizeof(buf);
3925 		info.offset = 0;
3926 		info.pos = 0;
3927 		tinfo = ahc_fetch_transinfo(ahc, channel,
3928 						channel == 'A' ? ahc->our_id
3929 							       : ahc->our_id_b,
3930 						target, &tstate);
3931 
3932 		/*
3933 		 * Don't bother reporting results while
3934 		 * negotiations are still pending.
3935 		 */
3936 		if (tinfo->curr.period != tinfo->goal.period
3937 		 || tinfo->curr.width != tinfo->goal.width
3938 		 || tinfo->curr.offset != tinfo->goal.offset
3939 		 || tinfo->curr.ppr_options != tinfo->goal.ppr_options)
3940 			if (bootverbose == 0)
3941 				break;
3942 
3943 		/*
3944 		 * Don't bother reporting results that
3945 		 * are identical to those last reported.
3946 		 */
3947 		target_offset = target;
3948 		if (channel == 'B')
3949 			target_offset += 8;
3950 		targ = ahc->platform_data->targets[target_offset];
3951 		if (targ == NULL)
3952 			break;
3953 		if (tinfo->curr.period == targ->last_tinfo.period
3954 		 && tinfo->curr.width == targ->last_tinfo.width
3955 		 && tinfo->curr.offset == targ->last_tinfo.offset
3956 		 && tinfo->curr.ppr_options == targ->last_tinfo.ppr_options)
3957 			if (bootverbose == 0)
3958 				break;
3959 
3960 		targ->last_tinfo.period = tinfo->curr.period;
3961 		targ->last_tinfo.width = tinfo->curr.width;
3962 		targ->last_tinfo.offset = tinfo->curr.offset;
3963 		targ->last_tinfo.ppr_options = tinfo->curr.ppr_options;
3964 
3965 		printf("(%s:%c:", ahc_name(ahc), channel);
3966 		if (target == CAM_TARGET_WILDCARD)
3967 			printf("*): ");
3968 		else
3969 			printf("%d): ", target);
3970 		ahc_format_transinfo(&info, &tinfo->curr);
3971 		if (info.pos < info.length)
3972 			*info.buffer = '\0';
3973 		else
3974 			buf[info.length - 1] = '\0';
3975 		printf("%s", buf);
3976 		break;
3977 	}
3978         case AC_SENT_BDR:
3979 	{
3980 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
3981 		WARN_ON(lun != CAM_LUN_WILDCARD);
3982 		scsi_report_device_reset(ahc->platform_data->host,
3983 					 channel - 'A', target);
3984 #else
3985 		Scsi_Device *scsi_dev;
3986 
3987 		/*
3988 		 * Find the SCSI device associated with this
3989 		 * request and indicate that a UA is expected.
3990 		 */
3991 		for (scsi_dev = ahc->platform_data->host->host_queue;
3992 		     scsi_dev != NULL; scsi_dev = scsi_dev->next) {
3993 			if (channel - 'A' == scsi_dev->channel
3994 			 && target == scsi_dev->id
3995 			 && (lun == CAM_LUN_WILDCARD
3996 			  || lun == scsi_dev->lun)) {
3997 				scsi_dev->was_reset = 1;
3998 				scsi_dev->expecting_cc_ua = 1;
3999 			}
4000 		}
4001 #endif
4002 		break;
4003 	}
4004         case AC_BUS_RESET:
4005 		if (ahc->platform_data->host != NULL) {
4006 			scsi_report_bus_reset(ahc->platform_data->host,
4007 					      channel - 'A');
4008 		}
4009                 break;
4010         default:
4011                 panic("ahc_send_async: Unexpected async event");
4012         }
4013 }
4014 
4015 /*
4016  * Calls the higher level scsi done function and frees the scb.
4017  */
4018 void
4019 ahc_done(struct ahc_softc *ahc, struct scb *scb)
4020 {
4021 	Scsi_Cmnd *cmd;
4022 	struct	   ahc_linux_device *dev;
4023 
4024 	LIST_REMOVE(scb, pending_links);
4025 	if ((scb->flags & SCB_UNTAGGEDQ) != 0) {
4026 		struct scb_tailq *untagged_q;
4027 		int target_offset;
4028 
4029 		target_offset = SCB_GET_TARGET_OFFSET(ahc, scb);
4030 		untagged_q = &(ahc->untagged_queues[target_offset]);
4031 		TAILQ_REMOVE(untagged_q, scb, links.tqe);
4032 		ahc_run_untagged_queue(ahc, untagged_q);
4033 	}
4034 
4035 	if ((scb->flags & SCB_ACTIVE) == 0) {
4036 		printf("SCB %d done'd twice\n", scb->hscb->tag);
4037 		ahc_dump_card_state(ahc);
4038 		panic("Stopping for safety");
4039 	}
4040 	cmd = scb->io_ctx;
4041 	dev = scb->platform_data->dev;
4042 	dev->active--;
4043 	dev->openings++;
4044 	if ((cmd->result & (CAM_DEV_QFRZN << 16)) != 0) {
4045 		cmd->result &= ~(CAM_DEV_QFRZN << 16);
4046 		dev->qfrozen--;
4047 	}
4048 	ahc_linux_unmap_scb(ahc, scb);
4049 
4050 	/*
4051 	 * Guard against stale sense data.
4052 	 * The Linux mid-layer assumes that sense
4053 	 * was retrieved anytime the first byte of
4054 	 * the sense buffer looks "sane".
4055 	 */
4056 	cmd->sense_buffer[0] = 0;
4057 	if (ahc_get_transaction_status(scb) == CAM_REQ_INPROG) {
4058 		uint32_t amount_xferred;
4059 
4060 		amount_xferred =
4061 		    ahc_get_transfer_length(scb) - ahc_get_residual(scb);
4062 		if ((scb->flags & SCB_TRANSMISSION_ERROR) != 0) {
4063 #ifdef AHC_DEBUG
4064 			if ((ahc_debug & AHC_SHOW_MISC) != 0) {
4065 				ahc_print_path(ahc, scb);
4066 				printf("Set CAM_UNCOR_PARITY\n");
4067 			}
4068 #endif
4069 			ahc_set_transaction_status(scb, CAM_UNCOR_PARITY);
4070 #ifdef AHC_REPORT_UNDERFLOWS
4071 		/*
4072 		 * This code is disabled by default as some
4073 		 * clients of the SCSI system do not properly
4074 		 * initialize the underflow parameter.  This
4075 		 * results in spurious termination of commands
4076 		 * that complete as expected (e.g. underflow is
4077 		 * allowed as command can return variable amounts
4078 		 * of data.
4079 		 */
4080 		} else if (amount_xferred < scb->io_ctx->underflow) {
4081 			u_int i;
4082 
4083 			ahc_print_path(ahc, scb);
4084 			printf("CDB:");
4085 			for (i = 0; i < scb->io_ctx->cmd_len; i++)
4086 				printf(" 0x%x", scb->io_ctx->cmnd[i]);
4087 			printf("\n");
4088 			ahc_print_path(ahc, scb);
4089 			printf("Saw underflow (%ld of %ld bytes). "
4090 			       "Treated as error\n",
4091 				ahc_get_residual(scb),
4092 				ahc_get_transfer_length(scb));
4093 			ahc_set_transaction_status(scb, CAM_DATA_RUN_ERR);
4094 #endif
4095 		} else {
4096 			ahc_set_transaction_status(scb, CAM_REQ_CMP);
4097 		}
4098 	} else if (ahc_get_transaction_status(scb) == CAM_SCSI_STATUS_ERROR) {
4099 		ahc_linux_handle_scsi_status(ahc, dev, scb);
4100 	} else if (ahc_get_transaction_status(scb) == CAM_SEL_TIMEOUT) {
4101 		dev->flags |= AHC_DEV_UNCONFIGURED;
4102 		if (AHC_DV_CMD(cmd) == FALSE)
4103 			dev->target->flags &= ~AHC_DV_REQUIRED;
4104 	}
4105 	/*
4106 	 * Start DV for devices that require it assuming the first command
4107 	 * sent does not result in a selection timeout.
4108 	 */
4109 	if (ahc_get_transaction_status(scb) != CAM_SEL_TIMEOUT
4110 	 && (dev->target->flags & AHC_DV_REQUIRED) != 0)
4111 		ahc_linux_start_dv(ahc);
4112 
4113 	if (dev->openings == 1
4114 	 && ahc_get_transaction_status(scb) == CAM_REQ_CMP
4115 	 && ahc_get_scsi_status(scb) != SCSI_STATUS_QUEUE_FULL)
4116 		dev->tag_success_count++;
4117 	/*
4118 	 * Some devices deal with temporary internal resource
4119 	 * shortages by returning queue full.  When the queue
4120 	 * full occurrs, we throttle back.  Slowly try to get
4121 	 * back to our previous queue depth.
4122 	 */
4123 	if ((dev->openings + dev->active) < dev->maxtags
4124 	 && dev->tag_success_count > AHC_TAG_SUCCESS_INTERVAL) {
4125 		dev->tag_success_count = 0;
4126 		dev->openings++;
4127 	}
4128 
4129 	if (dev->active == 0)
4130 		dev->commands_since_idle_or_otag = 0;
4131 
4132 	if (TAILQ_EMPTY(&dev->busyq)) {
4133 		if ((dev->flags & AHC_DEV_UNCONFIGURED) != 0
4134 		 && dev->active == 0
4135 	 	 && (dev->flags & AHC_DEV_TIMER_ACTIVE) == 0)
4136 			ahc_linux_free_device(ahc, dev);
4137 	} else if ((dev->flags & AHC_DEV_ON_RUN_LIST) == 0) {
4138 		TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq, dev, links);
4139 		dev->flags |= AHC_DEV_ON_RUN_LIST;
4140 	}
4141 
4142 	if ((scb->flags & SCB_RECOVERY_SCB) != 0) {
4143 		printf("Recovery SCB completes\n");
4144 		if (ahc_get_transaction_status(scb) == CAM_BDR_SENT
4145 		 || ahc_get_transaction_status(scb) == CAM_REQ_ABORTED)
4146 			ahc_set_transaction_status(scb, CAM_CMD_TIMEOUT);
4147 		if ((ahc->platform_data->flags & AHC_UP_EH_SEMAPHORE) != 0) {
4148 			ahc->platform_data->flags &= ~AHC_UP_EH_SEMAPHORE;
4149 			up(&ahc->platform_data->eh_sem);
4150 		}
4151 	}
4152 
4153 	ahc_free_scb(ahc, scb);
4154 	ahc_linux_queue_cmd_complete(ahc, cmd);
4155 
4156 	if ((ahc->platform_data->flags & AHC_DV_WAIT_SIMQ_EMPTY) != 0
4157 	 && LIST_FIRST(&ahc->pending_scbs) == NULL) {
4158 		ahc->platform_data->flags &= ~AHC_DV_WAIT_SIMQ_EMPTY;
4159 		up(&ahc->platform_data->dv_sem);
4160 	}
4161 
4162 }
4163 
4164 static void
4165 ahc_linux_handle_scsi_status(struct ahc_softc *ahc,
4166 			     struct ahc_linux_device *dev, struct scb *scb)
4167 {
4168 	struct	ahc_devinfo devinfo;
4169 
4170 	ahc_compile_devinfo(&devinfo,
4171 			    ahc->our_id,
4172 			    dev->target->target, dev->lun,
4173 			    dev->target->channel == 0 ? 'A' : 'B',
4174 			    ROLE_INITIATOR);
4175 
4176 	/*
4177 	 * We don't currently trust the mid-layer to
4178 	 * properly deal with queue full or busy.  So,
4179 	 * when one occurs, we tell the mid-layer to
4180 	 * unconditionally requeue the command to us
4181 	 * so that we can retry it ourselves.  We also
4182 	 * implement our own throttling mechanism so
4183 	 * we don't clobber the device with too many
4184 	 * commands.
4185 	 */
4186 	switch (ahc_get_scsi_status(scb)) {
4187 	default:
4188 		break;
4189 	case SCSI_STATUS_CHECK_COND:
4190 	case SCSI_STATUS_CMD_TERMINATED:
4191 	{
4192 		Scsi_Cmnd *cmd;
4193 
4194 		/*
4195 		 * Copy sense information to the OS's cmd
4196 		 * structure if it is available.
4197 		 */
4198 		cmd = scb->io_ctx;
4199 		if (scb->flags & SCB_SENSE) {
4200 			u_int sense_size;
4201 
4202 			sense_size = MIN(sizeof(struct scsi_sense_data)
4203 				       - ahc_get_sense_residual(scb),
4204 					 sizeof(cmd->sense_buffer));
4205 			memcpy(cmd->sense_buffer,
4206 			       ahc_get_sense_buf(ahc, scb), sense_size);
4207 			if (sense_size < sizeof(cmd->sense_buffer))
4208 				memset(&cmd->sense_buffer[sense_size], 0,
4209 				       sizeof(cmd->sense_buffer) - sense_size);
4210 			cmd->result |= (DRIVER_SENSE << 24);
4211 #ifdef AHC_DEBUG
4212 			if (ahc_debug & AHC_SHOW_SENSE) {
4213 				int i;
4214 
4215 				printf("Copied %d bytes of sense data:",
4216 				       sense_size);
4217 				for (i = 0; i < sense_size; i++) {
4218 					if ((i & 0xF) == 0)
4219 						printf("\n");
4220 					printf("0x%x ", cmd->sense_buffer[i]);
4221 				}
4222 				printf("\n");
4223 			}
4224 #endif
4225 		}
4226 		break;
4227 	}
4228 	case SCSI_STATUS_QUEUE_FULL:
4229 	{
4230 		/*
4231 		 * By the time the core driver has returned this
4232 		 * command, all other commands that were queued
4233 		 * to us but not the device have been returned.
4234 		 * This ensures that dev->active is equal to
4235 		 * the number of commands actually queued to
4236 		 * the device.
4237 		 */
4238 		dev->tag_success_count = 0;
4239 		if (dev->active != 0) {
4240 			/*
4241 			 * Drop our opening count to the number
4242 			 * of commands currently outstanding.
4243 			 */
4244 			dev->openings = 0;
4245 /*
4246 			ahc_print_path(ahc, scb);
4247 			printf("Dropping tag count to %d\n", dev->active);
4248  */
4249 			if (dev->active == dev->tags_on_last_queuefull) {
4250 
4251 				dev->last_queuefull_same_count++;
4252 				/*
4253 				 * If we repeatedly see a queue full
4254 				 * at the same queue depth, this
4255 				 * device has a fixed number of tag
4256 				 * slots.  Lock in this tag depth
4257 				 * so we stop seeing queue fulls from
4258 				 * this device.
4259 				 */
4260 				if (dev->last_queuefull_same_count
4261 				 == AHC_LOCK_TAGS_COUNT) {
4262 					dev->maxtags = dev->active;
4263 					ahc_print_path(ahc, scb);
4264 					printf("Locking max tag count at %d\n",
4265 					       dev->active);
4266 				}
4267 			} else {
4268 				dev->tags_on_last_queuefull = dev->active;
4269 				dev->last_queuefull_same_count = 0;
4270 			}
4271 			ahc_set_transaction_status(scb, CAM_REQUEUE_REQ);
4272 			ahc_set_scsi_status(scb, SCSI_STATUS_OK);
4273 			ahc_platform_set_tags(ahc, &devinfo,
4274 				     (dev->flags & AHC_DEV_Q_BASIC)
4275 				   ? AHC_QUEUE_BASIC : AHC_QUEUE_TAGGED);
4276 			break;
4277 		}
4278 		/*
4279 		 * Drop down to a single opening, and treat this
4280 		 * as if the target returned BUSY SCSI status.
4281 		 */
4282 		dev->openings = 1;
4283 		ahc_set_scsi_status(scb, SCSI_STATUS_BUSY);
4284 		ahc_platform_set_tags(ahc, &devinfo,
4285 			     (dev->flags & AHC_DEV_Q_BASIC)
4286 			   ? AHC_QUEUE_BASIC : AHC_QUEUE_TAGGED);
4287 		/* FALLTHROUGH */
4288 	}
4289 	case SCSI_STATUS_BUSY:
4290 	{
4291 		/*
4292 		 * Set a short timer to defer sending commands for
4293 		 * a bit since Linux will not delay in this case.
4294 		 */
4295 		if ((dev->flags & AHC_DEV_TIMER_ACTIVE) != 0) {
4296 			printf("%s:%c:%d: Device Timer still active during "
4297 			       "busy processing\n", ahc_name(ahc),
4298 				dev->target->channel, dev->target->target);
4299 			break;
4300 		}
4301 		dev->flags |= AHC_DEV_TIMER_ACTIVE;
4302 		dev->qfrozen++;
4303 		init_timer(&dev->timer);
4304 		dev->timer.data = (u_long)dev;
4305 		dev->timer.expires = jiffies + (HZ/2);
4306 		dev->timer.function = ahc_linux_dev_timed_unfreeze;
4307 		add_timer(&dev->timer);
4308 		break;
4309 	}
4310 	}
4311 }
4312 
4313 static void
4314 ahc_linux_queue_cmd_complete(struct ahc_softc *ahc, Scsi_Cmnd *cmd)
4315 {
4316 	/*
4317 	 * Typically, the complete queue has very few entries
4318 	 * queued to it before the queue is emptied by
4319 	 * ahc_linux_run_complete_queue, so sorting the entries
4320 	 * by generation number should be inexpensive.
4321 	 * We perform the sort so that commands that complete
4322 	 * with an error are retuned in the order origionally
4323 	 * queued to the controller so that any subsequent retries
4324 	 * are performed in order.  The underlying ahc routines do
4325 	 * not guarantee the order that aborted commands will be
4326 	 * returned to us.
4327 	 */
4328 	struct ahc_completeq *completeq;
4329 	struct ahc_cmd *list_cmd;
4330 	struct ahc_cmd *acmd;
4331 
4332 	/*
4333 	 * Map CAM error codes into Linux Error codes.  We
4334 	 * avoid the conversion so that the DV code has the
4335 	 * full error information available when making
4336 	 * state change decisions.
4337 	 */
4338 	if (AHC_DV_CMD(cmd) == FALSE) {
4339 		u_int new_status;
4340 
4341 		switch (ahc_cmd_get_transaction_status(cmd)) {
4342 		case CAM_REQ_INPROG:
4343 		case CAM_REQ_CMP:
4344 		case CAM_SCSI_STATUS_ERROR:
4345 			new_status = DID_OK;
4346 			break;
4347 		case CAM_REQ_ABORTED:
4348 			new_status = DID_ABORT;
4349 			break;
4350 		case CAM_BUSY:
4351 			new_status = DID_BUS_BUSY;
4352 			break;
4353 		case CAM_REQ_INVALID:
4354 		case CAM_PATH_INVALID:
4355 			new_status = DID_BAD_TARGET;
4356 			break;
4357 		case CAM_SEL_TIMEOUT:
4358 			new_status = DID_NO_CONNECT;
4359 			break;
4360 		case CAM_SCSI_BUS_RESET:
4361 		case CAM_BDR_SENT:
4362 			new_status = DID_RESET;
4363 			break;
4364 		case CAM_UNCOR_PARITY:
4365 			new_status = DID_PARITY;
4366 			break;
4367 		case CAM_CMD_TIMEOUT:
4368 			new_status = DID_TIME_OUT;
4369 			break;
4370 		case CAM_UA_ABORT:
4371 		case CAM_REQ_CMP_ERR:
4372 		case CAM_AUTOSENSE_FAIL:
4373 		case CAM_NO_HBA:
4374 		case CAM_DATA_RUN_ERR:
4375 		case CAM_UNEXP_BUSFREE:
4376 		case CAM_SEQUENCE_FAIL:
4377 		case CAM_CCB_LEN_ERR:
4378 		case CAM_PROVIDE_FAIL:
4379 		case CAM_REQ_TERMIO:
4380 		case CAM_UNREC_HBA_ERROR:
4381 		case CAM_REQ_TOO_BIG:
4382 			new_status = DID_ERROR;
4383 			break;
4384 		case CAM_REQUEUE_REQ:
4385 			/*
4386 			 * If we want the request requeued, make sure there
4387 			 * are sufficent retries.  In the old scsi error code,
4388 			 * we used to be able to specify a result code that
4389 			 * bypassed the retry count.  Now we must use this
4390 			 * hack.  We also "fake" a check condition with
4391 			 * a sense code of ABORTED COMMAND.  This seems to
4392 			 * evoke a retry even if this command is being sent
4393 			 * via the eh thread.  Ick!  Ick!  Ick!
4394 			 */
4395 			if (cmd->retries > 0)
4396 				cmd->retries--;
4397 			new_status = DID_OK;
4398 			ahc_cmd_set_scsi_status(cmd, SCSI_STATUS_CHECK_COND);
4399 			cmd->result |= (DRIVER_SENSE << 24);
4400 			memset(cmd->sense_buffer, 0,
4401 			       sizeof(cmd->sense_buffer));
4402 			cmd->sense_buffer[0] = SSD_ERRCODE_VALID
4403 					     | SSD_CURRENT_ERROR;
4404 			cmd->sense_buffer[2] = SSD_KEY_ABORTED_COMMAND;
4405 			break;
4406 		default:
4407 			/* We should never get here */
4408 			new_status = DID_ERROR;
4409 			break;
4410 		}
4411 
4412 		ahc_cmd_set_transaction_status(cmd, new_status);
4413 	}
4414 
4415 	completeq = &ahc->platform_data->completeq;
4416 	list_cmd = TAILQ_FIRST(completeq);
4417 	acmd = (struct ahc_cmd *)cmd;
4418 	while (list_cmd != NULL
4419 	    && acmd_scsi_cmd(list_cmd).serial_number
4420 	     < acmd_scsi_cmd(acmd).serial_number)
4421 		list_cmd = TAILQ_NEXT(list_cmd, acmd_links.tqe);
4422 	if (list_cmd != NULL)
4423 		TAILQ_INSERT_BEFORE(list_cmd, acmd, acmd_links.tqe);
4424 	else
4425 		TAILQ_INSERT_TAIL(completeq, acmd, acmd_links.tqe);
4426 }
4427 
4428 static void
4429 ahc_linux_filter_inquiry(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
4430 {
4431 	struct	scsi_inquiry_data *sid;
4432 	struct	ahc_initiator_tinfo *tinfo;
4433 	struct	ahc_transinfo *user;
4434 	struct	ahc_transinfo *goal;
4435 	struct	ahc_transinfo *curr;
4436 	struct	ahc_tmode_tstate *tstate;
4437 	struct	ahc_syncrate *syncrate;
4438 	struct	ahc_linux_device *dev;
4439 	u_int	maxsync;
4440 	u_int	width;
4441 	u_int	period;
4442 	u_int	offset;
4443 	u_int	ppr_options;
4444 	u_int	trans_version;
4445 	u_int	prot_version;
4446 
4447 	/*
4448 	 * Determine if this lun actually exists.  If so,
4449 	 * hold on to its corresponding device structure.
4450 	 * If not, make sure we release the device and
4451 	 * don't bother processing the rest of this inquiry
4452 	 * command.
4453 	 */
4454 	dev = ahc_linux_get_device(ahc, devinfo->channel - 'A',
4455 				   devinfo->target, devinfo->lun,
4456 				   /*alloc*/TRUE);
4457 
4458 	sid = (struct scsi_inquiry_data *)dev->target->inq_data;
4459 	if (SID_QUAL(sid) == SID_QUAL_LU_CONNECTED) {
4460 
4461 		dev->flags &= ~AHC_DEV_UNCONFIGURED;
4462 	} else {
4463 		dev->flags |= AHC_DEV_UNCONFIGURED;
4464 		return;
4465 	}
4466 
4467 	/*
4468 	 * Update our notion of this device's transfer
4469 	 * negotiation capabilities.
4470 	 */
4471 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel,
4472 				    devinfo->our_scsiid,
4473 				    devinfo->target, &tstate);
4474 	user = &tinfo->user;
4475 	goal = &tinfo->goal;
4476 	curr = &tinfo->curr;
4477 	width = user->width;
4478 	period = user->period;
4479 	offset = user->offset;
4480 	ppr_options = user->ppr_options;
4481 	trans_version = user->transport_version;
4482 	prot_version = MIN(user->protocol_version, SID_ANSI_REV(sid));
4483 
4484 	/*
4485 	 * Only attempt SPI3/4 once we've verified that
4486 	 * the device claims to support SPI3/4 features.
4487 	 */
4488 	if (prot_version < SCSI_REV_2)
4489 		trans_version = SID_ANSI_REV(sid);
4490 	else
4491 		trans_version = SCSI_REV_2;
4492 
4493 	if ((sid->flags & SID_WBus16) == 0)
4494 		width = MSG_EXT_WDTR_BUS_8_BIT;
4495 	if ((sid->flags & SID_Sync) == 0) {
4496 		period = 0;
4497 		offset = 0;
4498 		ppr_options = 0;
4499 	}
4500 	if ((sid->spi3data & SID_SPI_QAS) == 0)
4501 		ppr_options &= ~MSG_EXT_PPR_QAS_REQ;
4502 	if ((sid->spi3data & SID_SPI_CLOCK_DT) == 0)
4503 		ppr_options &= MSG_EXT_PPR_QAS_REQ;
4504 	if ((sid->spi3data & SID_SPI_IUS) == 0)
4505 		ppr_options &= (MSG_EXT_PPR_DT_REQ
4506 			      | MSG_EXT_PPR_QAS_REQ);
4507 
4508 	if (prot_version > SCSI_REV_2
4509 	 && ppr_options != 0)
4510 		trans_version = user->transport_version;
4511 
4512 	ahc_validate_width(ahc, /*tinfo limit*/NULL, &width, ROLE_UNKNOWN);
4513 	if ((ahc->features & AHC_ULTRA2) != 0)
4514 		maxsync = AHC_SYNCRATE_DT;
4515 	else if ((ahc->features & AHC_ULTRA) != 0)
4516 		maxsync = AHC_SYNCRATE_ULTRA;
4517 	else
4518 		maxsync = AHC_SYNCRATE_FAST;
4519 
4520 	syncrate = ahc_find_syncrate(ahc, &period, &ppr_options, maxsync);
4521 	ahc_validate_offset(ahc, /*tinfo limit*/NULL, syncrate,
4522 			    &offset, width, ROLE_UNKNOWN);
4523 	if (offset == 0 || period == 0) {
4524 		period = 0;
4525 		offset = 0;
4526 		ppr_options = 0;
4527 	}
4528 	/* Apply our filtered user settings. */
4529 	curr->transport_version = trans_version;
4530 	curr->protocol_version = prot_version;
4531 	ahc_set_width(ahc, devinfo, width, AHC_TRANS_GOAL, /*paused*/FALSE);
4532 	ahc_set_syncrate(ahc, devinfo, syncrate, period,
4533 			 offset, ppr_options, AHC_TRANS_GOAL,
4534 			 /*paused*/FALSE);
4535 }
4536 
4537 static void
4538 ahc_linux_sem_timeout(u_long arg)
4539 {
4540 	struct	ahc_softc *ahc;
4541 	u_long	s;
4542 
4543 	ahc = (struct ahc_softc *)arg;
4544 
4545 	ahc_lock(ahc, &s);
4546 	if ((ahc->platform_data->flags & AHC_UP_EH_SEMAPHORE) != 0) {
4547 		ahc->platform_data->flags &= ~AHC_UP_EH_SEMAPHORE;
4548 		up(&ahc->platform_data->eh_sem);
4549 	}
4550 	ahc_unlock(ahc, &s);
4551 }
4552 
4553 static void
4554 ahc_linux_freeze_simq(struct ahc_softc *ahc)
4555 {
4556 	ahc->platform_data->qfrozen++;
4557 	if (ahc->platform_data->qfrozen == 1) {
4558 		scsi_block_requests(ahc->platform_data->host);
4559 
4560 		/* XXX What about Twin channels? */
4561 		ahc_platform_abort_scbs(ahc, CAM_TARGET_WILDCARD, ALL_CHANNELS,
4562 					CAM_LUN_WILDCARD, SCB_LIST_NULL,
4563 					ROLE_INITIATOR, CAM_REQUEUE_REQ);
4564 	}
4565 }
4566 
4567 static void
4568 ahc_linux_release_simq(u_long arg)
4569 {
4570 	struct ahc_softc *ahc;
4571 	u_long s;
4572 	int    unblock_reqs;
4573 
4574 	ahc = (struct ahc_softc *)arg;
4575 
4576 	unblock_reqs = 0;
4577 	ahc_lock(ahc, &s);
4578 	if (ahc->platform_data->qfrozen > 0)
4579 		ahc->platform_data->qfrozen--;
4580 	if (ahc->platform_data->qfrozen == 0)
4581 		unblock_reqs = 1;
4582 	if (AHC_DV_SIMQ_FROZEN(ahc)
4583 	 && ((ahc->platform_data->flags & AHC_DV_WAIT_SIMQ_RELEASE) != 0)) {
4584 		ahc->platform_data->flags &= ~AHC_DV_WAIT_SIMQ_RELEASE;
4585 		up(&ahc->platform_data->dv_sem);
4586 	}
4587 	ahc_schedule_runq(ahc);
4588 	ahc_unlock(ahc, &s);
4589 	/*
4590 	 * There is still a race here.  The mid-layer
4591 	 * should keep its own freeze count and use
4592 	 * a bottom half handler to run the queues
4593 	 * so we can unblock with our own lock held.
4594 	 */
4595 	if (unblock_reqs)
4596 		scsi_unblock_requests(ahc->platform_data->host);
4597 }
4598 
4599 static void
4600 ahc_linux_dev_timed_unfreeze(u_long arg)
4601 {
4602 	struct ahc_linux_device *dev;
4603 	struct ahc_softc *ahc;
4604 	u_long s;
4605 
4606 	dev = (struct ahc_linux_device *)arg;
4607 	ahc = dev->target->ahc;
4608 	ahc_lock(ahc, &s);
4609 	dev->flags &= ~AHC_DEV_TIMER_ACTIVE;
4610 	if (dev->qfrozen > 0)
4611 		dev->qfrozen--;
4612 	if (dev->qfrozen == 0
4613 	 && (dev->flags & AHC_DEV_ON_RUN_LIST) == 0)
4614 		ahc_linux_run_device_queue(ahc, dev);
4615 	if (TAILQ_EMPTY(&dev->busyq)
4616 	 && dev->active == 0)
4617 		__ahc_linux_free_device(ahc, dev);
4618 	ahc_unlock(ahc, &s);
4619 }
4620 
4621 static int
4622 ahc_linux_queue_recovery_cmd(Scsi_Cmnd *cmd, scb_flag flag)
4623 {
4624 	struct ahc_softc *ahc;
4625 	struct ahc_cmd *acmd;
4626 	struct ahc_cmd *list_acmd;
4627 	struct ahc_linux_device *dev;
4628 	struct scb *pending_scb;
4629 	u_long s;
4630 	u_int  saved_scbptr;
4631 	u_int  active_scb_index;
4632 	u_int  last_phase;
4633 	u_int  saved_scsiid;
4634 	u_int  cdb_byte;
4635 	int    retval;
4636 	int    was_paused;
4637 	int    paused;
4638 	int    wait;
4639 	int    disconnected;
4640 
4641 	pending_scb = NULL;
4642 	paused = FALSE;
4643 	wait = FALSE;
4644 	ahc = *(struct ahc_softc **)cmd->device->host->hostdata;
4645 	acmd = (struct ahc_cmd *)cmd;
4646 
4647 	printf("%s:%d:%d:%d: Attempting to queue a%s message\n",
4648 	       ahc_name(ahc), cmd->device->channel,
4649 	       cmd->device->id, cmd->device->lun,
4650 	       flag == SCB_ABORT ? "n ABORT" : " TARGET RESET");
4651 
4652 	printf("CDB:");
4653 	for (cdb_byte = 0; cdb_byte < cmd->cmd_len; cdb_byte++)
4654 		printf(" 0x%x", cmd->cmnd[cdb_byte]);
4655 	printf("\n");
4656 
4657 	/*
4658 	 * In all versions of Linux, we have to work around
4659 	 * a major flaw in how the mid-layer is locked down
4660 	 * if we are to sleep successfully in our error handler
4661 	 * while allowing our interrupt handler to run.  Since
4662 	 * the midlayer acquires either the io_request_lock or
4663 	 * our lock prior to calling us, we must use the
4664 	 * spin_unlock_irq() method for unlocking our lock.
4665 	 * This will force interrupts to be enabled on the
4666 	 * current CPU.  Since the EH thread should not have
4667 	 * been running with CPU interrupts disabled other than
4668 	 * by acquiring either the io_request_lock or our own
4669 	 * lock, this *should* be safe.
4670 	 */
4671 	ahc_midlayer_entrypoint_lock(ahc, &s);
4672 
4673 	/*
4674 	 * First determine if we currently own this command.
4675 	 * Start by searching the device queue.  If not found
4676 	 * there, check the pending_scb list.  If not found
4677 	 * at all, and the system wanted us to just abort the
4678 	 * command, return success.
4679 	 */
4680 	dev = ahc_linux_get_device(ahc, cmd->device->channel, cmd->device->id,
4681 				   cmd->device->lun, /*alloc*/FALSE);
4682 
4683 	if (dev == NULL) {
4684 		/*
4685 		 * No target device for this command exists,
4686 		 * so we must not still own the command.
4687 		 */
4688 		printf("%s:%d:%d:%d: Is not an active device\n",
4689 		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
4690 		       cmd->device->lun);
4691 		retval = SUCCESS;
4692 		goto no_cmd;
4693 	}
4694 
4695 	TAILQ_FOREACH(list_acmd, &dev->busyq, acmd_links.tqe) {
4696 		if (list_acmd == acmd)
4697 			break;
4698 	}
4699 
4700 	if (list_acmd != NULL) {
4701 		printf("%s:%d:%d:%d: Command found on device queue\n",
4702 		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
4703 		       cmd->device->lun);
4704 		if (flag == SCB_ABORT) {
4705 			TAILQ_REMOVE(&dev->busyq, list_acmd, acmd_links.tqe);
4706 			cmd->result = DID_ABORT << 16;
4707 			ahc_linux_queue_cmd_complete(ahc, cmd);
4708 			retval = SUCCESS;
4709 			goto done;
4710 		}
4711 	}
4712 
4713 	if ((dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED)) == 0
4714 	 && ahc_search_untagged_queues(ahc, cmd, cmd->device->id,
4715 				       cmd->device->channel + 'A',
4716 				       cmd->device->lun,
4717 				       CAM_REQ_ABORTED, SEARCH_COMPLETE) != 0) {
4718 		printf("%s:%d:%d:%d: Command found on untagged queue\n",
4719 		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
4720 		       cmd->device->lun);
4721 		retval = SUCCESS;
4722 		goto done;
4723 	}
4724 
4725 	/*
4726 	 * See if we can find a matching cmd in the pending list.
4727 	 */
4728 	LIST_FOREACH(pending_scb, &ahc->pending_scbs, pending_links) {
4729 		if (pending_scb->io_ctx == cmd)
4730 			break;
4731 	}
4732 
4733 	if (pending_scb == NULL && flag == SCB_DEVICE_RESET) {
4734 
4735 		/* Any SCB for this device will do for a target reset */
4736 		LIST_FOREACH(pending_scb, &ahc->pending_scbs, pending_links) {
4737 		  	if (ahc_match_scb(ahc, pending_scb, cmd->device->id,
4738 					  cmd->device->channel + 'A',
4739 					  CAM_LUN_WILDCARD,
4740 					  SCB_LIST_NULL, ROLE_INITIATOR) == 0)
4741 				break;
4742 		}
4743 	}
4744 
4745 	if (pending_scb == NULL) {
4746 		printf("%s:%d:%d:%d: Command not found\n",
4747 		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
4748 		       cmd->device->lun);
4749 		goto no_cmd;
4750 	}
4751 
4752 	if ((pending_scb->flags & SCB_RECOVERY_SCB) != 0) {
4753 		/*
4754 		 * We can't queue two recovery actions using the same SCB
4755 		 */
4756 		retval = FAILED;
4757 		goto  done;
4758 	}
4759 
4760 	/*
4761 	 * Ensure that the card doesn't do anything
4762 	 * behind our back and that we didn't "just" miss
4763 	 * an interrupt that would affect this cmd.
4764 	 */
4765 	was_paused = ahc_is_paused(ahc);
4766 	ahc_pause_and_flushwork(ahc);
4767 	paused = TRUE;
4768 
4769 	if ((pending_scb->flags & SCB_ACTIVE) == 0) {
4770 		printf("%s:%d:%d:%d: Command already completed\n",
4771 		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
4772 		       cmd->device->lun);
4773 		goto no_cmd;
4774 	}
4775 
4776 	printf("%s: At time of recovery, card was %spaused\n",
4777 	       ahc_name(ahc), was_paused ? "" : "not ");
4778 	ahc_dump_card_state(ahc);
4779 
4780 	disconnected = TRUE;
4781 	if (flag == SCB_ABORT) {
4782 		if (ahc_search_qinfifo(ahc, cmd->device->id,
4783 				       cmd->device->channel + 'A',
4784 				       cmd->device->lun,
4785 				       pending_scb->hscb->tag,
4786 				       ROLE_INITIATOR, CAM_REQ_ABORTED,
4787 				       SEARCH_COMPLETE) > 0) {
4788 			printf("%s:%d:%d:%d: Cmd aborted from QINFIFO\n",
4789 			       ahc_name(ahc), cmd->device->channel,
4790 					cmd->device->id, cmd->device->lun);
4791 			retval = SUCCESS;
4792 			goto done;
4793 		}
4794 	} else if (ahc_search_qinfifo(ahc, cmd->device->id,
4795 				      cmd->device->channel + 'A',
4796 				      cmd->device->lun, pending_scb->hscb->tag,
4797 				      ROLE_INITIATOR, /*status*/0,
4798 				      SEARCH_COUNT) > 0) {
4799 		disconnected = FALSE;
4800 	}
4801 
4802 	if (disconnected && (ahc_inb(ahc, SEQ_FLAGS) & NOT_IDENTIFIED) == 0) {
4803 		struct scb *bus_scb;
4804 
4805 		bus_scb = ahc_lookup_scb(ahc, ahc_inb(ahc, SCB_TAG));
4806 		if (bus_scb == pending_scb)
4807 			disconnected = FALSE;
4808 		else if (flag != SCB_ABORT
4809 		      && ahc_inb(ahc, SAVED_SCSIID) == pending_scb->hscb->scsiid
4810 		      && ahc_inb(ahc, SAVED_LUN) == SCB_GET_LUN(pending_scb))
4811 			disconnected = FALSE;
4812 	}
4813 
4814 	/*
4815 	 * At this point, pending_scb is the scb associated with the
4816 	 * passed in command.  That command is currently active on the
4817 	 * bus, is in the disconnected state, or we're hoping to find
4818 	 * a command for the same target active on the bus to abuse to
4819 	 * send a BDR.  Queue the appropriate message based on which of
4820 	 * these states we are in.
4821 	 */
4822 	last_phase = ahc_inb(ahc, LASTPHASE);
4823 	saved_scbptr = ahc_inb(ahc, SCBPTR);
4824 	active_scb_index = ahc_inb(ahc, SCB_TAG);
4825 	saved_scsiid = ahc_inb(ahc, SAVED_SCSIID);
4826 	if (last_phase != P_BUSFREE
4827 	 && (pending_scb->hscb->tag == active_scb_index
4828 	  || (flag == SCB_DEVICE_RESET
4829 	   && SCSIID_TARGET(ahc, saved_scsiid) == cmd->device->id))) {
4830 
4831 		/*
4832 		 * We're active on the bus, so assert ATN
4833 		 * and hope that the target responds.
4834 		 */
4835 		pending_scb = ahc_lookup_scb(ahc, active_scb_index);
4836 		pending_scb->flags |= SCB_RECOVERY_SCB|flag;
4837 		ahc_outb(ahc, MSG_OUT, HOST_MSG);
4838 		ahc_outb(ahc, SCSISIGO, last_phase|ATNO);
4839 		printf("%s:%d:%d:%d: Device is active, asserting ATN\n",
4840 		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
4841 		       cmd->device->lun);
4842 		wait = TRUE;
4843 	} else if (disconnected) {
4844 
4845 		/*
4846 		 * Actually re-queue this SCB in an attempt
4847 		 * to select the device before it reconnects.
4848 		 * In either case (selection or reselection),
4849 		 * we will now issue the approprate message
4850 		 * to the timed-out device.
4851 		 *
4852 		 * Set the MK_MESSAGE control bit indicating
4853 		 * that we desire to send a message.  We
4854 		 * also set the disconnected flag since
4855 		 * in the paging case there is no guarantee
4856 		 * that our SCB control byte matches the
4857 		 * version on the card.  We don't want the
4858 		 * sequencer to abort the command thinking
4859 		 * an unsolicited reselection occurred.
4860 		 */
4861 		pending_scb->hscb->control |= MK_MESSAGE|DISCONNECTED;
4862 		pending_scb->flags |= SCB_RECOVERY_SCB|flag;
4863 
4864 		/*
4865 		 * Remove any cached copy of this SCB in the
4866 		 * disconnected list in preparation for the
4867 		 * queuing of our abort SCB.  We use the
4868 		 * same element in the SCB, SCB_NEXT, for
4869 		 * both the qinfifo and the disconnected list.
4870 		 */
4871 		ahc_search_disc_list(ahc, cmd->device->id,
4872 				     cmd->device->channel + 'A',
4873 				     cmd->device->lun, pending_scb->hscb->tag,
4874 				     /*stop_on_first*/TRUE,
4875 				     /*remove*/TRUE,
4876 				     /*save_state*/FALSE);
4877 
4878 		/*
4879 		 * In the non-paging case, the sequencer will
4880 		 * never re-reference the in-core SCB.
4881 		 * To make sure we are notified during
4882 		 * reslection, set the MK_MESSAGE flag in
4883 		 * the card's copy of the SCB.
4884 		 */
4885 		if ((ahc->flags & AHC_PAGESCBS) == 0) {
4886 			ahc_outb(ahc, SCBPTR, pending_scb->hscb->tag);
4887 			ahc_outb(ahc, SCB_CONTROL,
4888 				 ahc_inb(ahc, SCB_CONTROL)|MK_MESSAGE);
4889 		}
4890 
4891 		/*
4892 		 * Clear out any entries in the QINFIFO first
4893 		 * so we are the next SCB for this target
4894 		 * to run.
4895 		 */
4896 		ahc_search_qinfifo(ahc, cmd->device->id,
4897 				   cmd->device->channel + 'A',
4898 				   cmd->device->lun, SCB_LIST_NULL,
4899 				   ROLE_INITIATOR, CAM_REQUEUE_REQ,
4900 				   SEARCH_COMPLETE);
4901 		ahc_qinfifo_requeue_tail(ahc, pending_scb);
4902 		ahc_outb(ahc, SCBPTR, saved_scbptr);
4903 		ahc_print_path(ahc, pending_scb);
4904 		printf("Device is disconnected, re-queuing SCB\n");
4905 		wait = TRUE;
4906 	} else {
4907 		printf("%s:%d:%d:%d: Unable to deliver message\n",
4908 		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
4909 		       cmd->device->lun);
4910 		retval = FAILED;
4911 		goto done;
4912 	}
4913 
4914 no_cmd:
4915 	/*
4916 	 * Our assumption is that if we don't have the command, no
4917 	 * recovery action was required, so we return success.  Again,
4918 	 * the semantics of the mid-layer recovery engine are not
4919 	 * well defined, so this may change in time.
4920 	 */
4921 	retval = SUCCESS;
4922 done:
4923 	if (paused)
4924 		ahc_unpause(ahc);
4925 	if (wait) {
4926 		struct timer_list timer;
4927 		int ret;
4928 
4929 		ahc->platform_data->flags |= AHC_UP_EH_SEMAPHORE;
4930 		spin_unlock_irq(&ahc->platform_data->spin_lock);
4931 		init_timer(&timer);
4932 		timer.data = (u_long)ahc;
4933 		timer.expires = jiffies + (5 * HZ);
4934 		timer.function = ahc_linux_sem_timeout;
4935 		add_timer(&timer);
4936 		printf("Recovery code sleeping\n");
4937 		down(&ahc->platform_data->eh_sem);
4938 		printf("Recovery code awake\n");
4939         	ret = del_timer_sync(&timer);
4940 		if (ret == 0) {
4941 			printf("Timer Expired\n");
4942 			retval = FAILED;
4943 		}
4944 		spin_lock_irq(&ahc->platform_data->spin_lock);
4945 	}
4946 	ahc_schedule_runq(ahc);
4947 	ahc_linux_run_complete_queue(ahc);
4948 	ahc_midlayer_entrypoint_unlock(ahc, &s);
4949 	return (retval);
4950 }
4951 
4952 void
4953 ahc_platform_dump_card_state(struct ahc_softc *ahc)
4954 {
4955 	struct ahc_linux_device *dev;
4956 	int channel;
4957 	int maxchannel;
4958 	int target;
4959 	int maxtarget;
4960 	int lun;
4961 	int i;
4962 
4963 	maxchannel = (ahc->features & AHC_TWIN) ? 1 : 0;
4964 	maxtarget = (ahc->features & AHC_WIDE) ? 15 : 7;
4965 	for (channel = 0; channel <= maxchannel; channel++) {
4966 
4967 		for (target = 0; target <=maxtarget; target++) {
4968 
4969 			for (lun = 0; lun < AHC_NUM_LUNS; lun++) {
4970 				struct ahc_cmd *acmd;
4971 
4972 				dev = ahc_linux_get_device(ahc, channel, target,
4973 							   lun, /*alloc*/FALSE);
4974 				if (dev == NULL)
4975 					continue;
4976 
4977 				printf("DevQ(%d:%d:%d): ",
4978 				       channel, target, lun);
4979 				i = 0;
4980 				TAILQ_FOREACH(acmd, &dev->busyq,
4981 					      acmd_links.tqe) {
4982 					if (i++ > AHC_SCB_MAX)
4983 						break;
4984 				}
4985 				printf("%d waiting\n", i);
4986 			}
4987 		}
4988 	}
4989 }
4990 
4991 static void ahc_linux_exit(void);
4992 
4993 static int __init
4994 ahc_linux_init(void)
4995 {
4996 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
4997 	int rc = ahc_linux_detect(&aic7xxx_driver_template);
4998 	if (rc)
4999 		return rc;
5000 	ahc_linux_exit();
5001 	return -ENODEV;
5002 #else
5003 	scsi_register_module(MODULE_SCSI_HA, &aic7xxx_driver_template);
5004 	if (aic7xxx_driver_template.present == 0) {
5005 		scsi_unregister_module(MODULE_SCSI_HA,
5006 				       &aic7xxx_driver_template);
5007 		return (-ENODEV);
5008 	}
5009 
5010 	return (0);
5011 #endif
5012 }
5013 
5014 static void
5015 ahc_linux_exit(void)
5016 {
5017 	struct ahc_softc *ahc;
5018 
5019 	/*
5020 	 * Shutdown DV threads before going into the SCSI mid-layer.
5021 	 * This avoids situations where the mid-layer locks the entire
5022 	 * kernel so that waiting for our DV threads to exit leads
5023 	 * to deadlock.
5024 	 */
5025 	TAILQ_FOREACH(ahc, &ahc_tailq, links) {
5026 
5027 		ahc_linux_kill_dv_thread(ahc);
5028 	}
5029 
5030 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
5031 	/*
5032 	 * In 2.4 we have to unregister from the PCI core _after_
5033 	 * unregistering from the scsi midlayer to avoid dangling
5034 	 * references.
5035 	 */
5036 	scsi_unregister_module(MODULE_SCSI_HA, &aic7xxx_driver_template);
5037 #endif
5038 	ahc_linux_pci_exit();
5039 	ahc_linux_eisa_exit();
5040 }
5041 
5042 module_init(ahc_linux_init);
5043 module_exit(ahc_linux_exit);
5044