xref: /openbmc/linux/drivers/firewire/sbp2.c (revision 62e7ca52)
1 /*
2  * SBP2 driver (SCSI over IEEE1394)
3  *
4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20 
21 /*
22  * The basic structure of this driver is based on the old storage driver,
23  * drivers/ieee1394/sbp2.c, originally written by
24  *     James Goodwin <jamesg@filanet.com>
25  * with later contributions and ongoing maintenance from
26  *     Ben Collins <bcollins@debian.org>,
27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
28  * and many others.
29  */
30 
31 #include <linux/blkdev.h>
32 #include <linux/bug.h>
33 #include <linux/completion.h>
34 #include <linux/delay.h>
35 #include <linux/device.h>
36 #include <linux/dma-mapping.h>
37 #include <linux/firewire.h>
38 #include <linux/firewire-constants.h>
39 #include <linux/init.h>
40 #include <linux/jiffies.h>
41 #include <linux/kernel.h>
42 #include <linux/kref.h>
43 #include <linux/list.h>
44 #include <linux/mod_devicetable.h>
45 #include <linux/module.h>
46 #include <linux/moduleparam.h>
47 #include <linux/scatterlist.h>
48 #include <linux/slab.h>
49 #include <linux/spinlock.h>
50 #include <linux/string.h>
51 #include <linux/stringify.h>
52 #include <linux/workqueue.h>
53 
54 #include <asm/byteorder.h>
55 
56 #include <scsi/scsi.h>
57 #include <scsi/scsi_cmnd.h>
58 #include <scsi/scsi_device.h>
59 #include <scsi/scsi_host.h>
60 
61 /*
62  * So far only bridges from Oxford Semiconductor are known to support
63  * concurrent logins. Depending on firmware, four or two concurrent logins
64  * are possible on OXFW911 and newer Oxsemi bridges.
65  *
66  * Concurrent logins are useful together with cluster filesystems.
67  */
68 static bool sbp2_param_exclusive_login = 1;
69 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
70 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
71 		 "(default = Y, use N for concurrent initiators)");
72 
73 /*
74  * Flags for firmware oddities
75  *
76  * - 128kB max transfer
77  *   Limit transfer size. Necessary for some old bridges.
78  *
79  * - 36 byte inquiry
80  *   When scsi_mod probes the device, let the inquiry command look like that
81  *   from MS Windows.
82  *
83  * - skip mode page 8
84  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
85  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
86  *
87  * - fix capacity
88  *   Tell sd_mod to correct the last sector number reported by read_capacity.
89  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
90  *   Don't use this with devices which don't have this bug.
91  *
92  * - delay inquiry
93  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
94  *
95  * - power condition
96  *   Set the power condition field in the START STOP UNIT commands sent by
97  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
98  *   Some disks need this to spin down or to resume properly.
99  *
100  * - override internal blacklist
101  *   Instead of adding to the built-in blacklist, use only the workarounds
102  *   specified in the module load parameter.
103  *   Useful if a blacklist entry interfered with a non-broken device.
104  */
105 #define SBP2_WORKAROUND_128K_MAX_TRANS	0x1
106 #define SBP2_WORKAROUND_INQUIRY_36	0x2
107 #define SBP2_WORKAROUND_MODE_SENSE_8	0x4
108 #define SBP2_WORKAROUND_FIX_CAPACITY	0x8
109 #define SBP2_WORKAROUND_DELAY_INQUIRY	0x10
110 #define SBP2_INQUIRY_DELAY		12
111 #define SBP2_WORKAROUND_POWER_CONDITION	0x20
112 #define SBP2_WORKAROUND_OVERRIDE	0x100
113 
114 static int sbp2_param_workarounds;
115 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
116 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
117 	", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
118 	", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
119 	", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
120 	", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
121 	", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
122 	", set power condition in start stop unit = "
123 				  __stringify(SBP2_WORKAROUND_POWER_CONDITION)
124 	", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
125 	", or a combination)");
126 
127 /*
128  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
129  * and one struct scsi_device per sbp2_logical_unit.
130  */
131 struct sbp2_logical_unit {
132 	struct sbp2_target *tgt;
133 	struct list_head link;
134 	struct fw_address_handler address_handler;
135 	struct list_head orb_list;
136 
137 	u64 command_block_agent_address;
138 	u16 lun;
139 	int login_id;
140 
141 	/*
142 	 * The generation is updated once we've logged in or reconnected
143 	 * to the logical unit.  Thus, I/O to the device will automatically
144 	 * fail and get retried if it happens in a window where the device
145 	 * is not ready, e.g. after a bus reset but before we reconnect.
146 	 */
147 	int generation;
148 	int retries;
149 	work_func_t workfn;
150 	struct delayed_work work;
151 	bool has_sdev;
152 	bool blocked;
153 };
154 
155 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
156 {
157 	queue_delayed_work(fw_workqueue, &lu->work, delay);
158 }
159 
160 /*
161  * We create one struct sbp2_target per IEEE 1212 Unit Directory
162  * and one struct Scsi_Host per sbp2_target.
163  */
164 struct sbp2_target {
165 	struct fw_unit *unit;
166 	struct list_head lu_list;
167 
168 	u64 management_agent_address;
169 	u64 guid;
170 	int directory_id;
171 	int node_id;
172 	int address_high;
173 	unsigned int workarounds;
174 	unsigned int mgt_orb_timeout;
175 	unsigned int max_payload;
176 
177 	int dont_block;	/* counter for each logical unit */
178 	int blocked;	/* ditto */
179 };
180 
181 static struct fw_device *target_parent_device(struct sbp2_target *tgt)
182 {
183 	return fw_parent_device(tgt->unit);
184 }
185 
186 static const struct device *tgt_dev(const struct sbp2_target *tgt)
187 {
188 	return &tgt->unit->device;
189 }
190 
191 static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
192 {
193 	return &lu->tgt->unit->device;
194 }
195 
196 /* Impossible login_id, to detect logout attempt before successful login */
197 #define INVALID_LOGIN_ID 0x10000
198 
199 #define SBP2_ORB_TIMEOUT		2000U		/* Timeout in ms */
200 #define SBP2_ORB_NULL			0x80000000
201 #define SBP2_RETRY_LIMIT		0xf		/* 15 retries */
202 #define SBP2_CYCLE_LIMIT		(0xc8 << 12)	/* 200 125us cycles */
203 
204 /*
205  * There is no transport protocol limit to the CDB length,  but we implement
206  * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
207  */
208 #define SBP2_MAX_CDB_SIZE		16
209 
210 /*
211  * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
212  * for compatibility with earlier versions of this driver.
213  */
214 #define SBP2_MAX_SEG_SIZE		0xfffc
215 
216 /* Unit directory keys */
217 #define SBP2_CSR_UNIT_CHARACTERISTICS	0x3a
218 #define SBP2_CSR_FIRMWARE_REVISION	0x3c
219 #define SBP2_CSR_LOGICAL_UNIT_NUMBER	0x14
220 #define SBP2_CSR_UNIT_UNIQUE_ID		0x8d
221 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY	0xd4
222 
223 /* Management orb opcodes */
224 #define SBP2_LOGIN_REQUEST		0x0
225 #define SBP2_QUERY_LOGINS_REQUEST	0x1
226 #define SBP2_RECONNECT_REQUEST		0x3
227 #define SBP2_SET_PASSWORD_REQUEST	0x4
228 #define SBP2_LOGOUT_REQUEST		0x7
229 #define SBP2_ABORT_TASK_REQUEST		0xb
230 #define SBP2_ABORT_TASK_SET		0xc
231 #define SBP2_LOGICAL_UNIT_RESET		0xe
232 #define SBP2_TARGET_RESET_REQUEST	0xf
233 
234 /* Offsets for command block agent registers */
235 #define SBP2_AGENT_STATE		0x00
236 #define SBP2_AGENT_RESET		0x04
237 #define SBP2_ORB_POINTER		0x08
238 #define SBP2_DOORBELL			0x10
239 #define SBP2_UNSOLICITED_STATUS_ENABLE	0x14
240 
241 /* Status write response codes */
242 #define SBP2_STATUS_REQUEST_COMPLETE	0x0
243 #define SBP2_STATUS_TRANSPORT_FAILURE	0x1
244 #define SBP2_STATUS_ILLEGAL_REQUEST	0x2
245 #define SBP2_STATUS_VENDOR_DEPENDENT	0x3
246 
247 #define STATUS_GET_ORB_HIGH(v)		((v).status & 0xffff)
248 #define STATUS_GET_SBP_STATUS(v)	(((v).status >> 16) & 0xff)
249 #define STATUS_GET_LEN(v)		(((v).status >> 24) & 0x07)
250 #define STATUS_GET_DEAD(v)		(((v).status >> 27) & 0x01)
251 #define STATUS_GET_RESPONSE(v)		(((v).status >> 28) & 0x03)
252 #define STATUS_GET_SOURCE(v)		(((v).status >> 30) & 0x03)
253 #define STATUS_GET_ORB_LOW(v)		((v).orb_low)
254 #define STATUS_GET_DATA(v)		((v).data)
255 
256 struct sbp2_status {
257 	u32 status;
258 	u32 orb_low;
259 	u8 data[24];
260 };
261 
262 struct sbp2_pointer {
263 	__be32 high;
264 	__be32 low;
265 };
266 
267 struct sbp2_orb {
268 	struct fw_transaction t;
269 	struct kref kref;
270 	dma_addr_t request_bus;
271 	int rcode;
272 	void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
273 	struct list_head link;
274 };
275 
276 #define MANAGEMENT_ORB_LUN(v)			((v))
277 #define MANAGEMENT_ORB_FUNCTION(v)		((v) << 16)
278 #define MANAGEMENT_ORB_RECONNECT(v)		((v) << 20)
279 #define MANAGEMENT_ORB_EXCLUSIVE(v)		((v) ? 1 << 28 : 0)
280 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)	((v) << 29)
281 #define MANAGEMENT_ORB_NOTIFY			((1) << 31)
282 
283 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)	((v))
284 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)	((v) << 16)
285 
286 struct sbp2_management_orb {
287 	struct sbp2_orb base;
288 	struct {
289 		struct sbp2_pointer password;
290 		struct sbp2_pointer response;
291 		__be32 misc;
292 		__be32 length;
293 		struct sbp2_pointer status_fifo;
294 	} request;
295 	__be32 response[4];
296 	dma_addr_t response_bus;
297 	struct completion done;
298 	struct sbp2_status status;
299 };
300 
301 struct sbp2_login_response {
302 	__be32 misc;
303 	struct sbp2_pointer command_block_agent;
304 	__be32 reconnect_hold;
305 };
306 #define COMMAND_ORB_DATA_SIZE(v)	((v))
307 #define COMMAND_ORB_PAGE_SIZE(v)	((v) << 16)
308 #define COMMAND_ORB_PAGE_TABLE_PRESENT	((1) << 19)
309 #define COMMAND_ORB_MAX_PAYLOAD(v)	((v) << 20)
310 #define COMMAND_ORB_SPEED(v)		((v) << 24)
311 #define COMMAND_ORB_DIRECTION		((1) << 27)
312 #define COMMAND_ORB_REQUEST_FORMAT(v)	((v) << 29)
313 #define COMMAND_ORB_NOTIFY		((1) << 31)
314 
315 struct sbp2_command_orb {
316 	struct sbp2_orb base;
317 	struct {
318 		struct sbp2_pointer next;
319 		struct sbp2_pointer data_descriptor;
320 		__be32 misc;
321 		u8 command_block[SBP2_MAX_CDB_SIZE];
322 	} request;
323 	struct scsi_cmnd *cmd;
324 	struct sbp2_logical_unit *lu;
325 
326 	struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
327 	dma_addr_t page_table_bus;
328 };
329 
330 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
331 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
332 
333 /*
334  * List of devices with known bugs.
335  *
336  * The firmware_revision field, masked with 0xffff00, is the best
337  * indicator for the type of bridge chip of a device.  It yields a few
338  * false positives but this did not break correctly behaving devices
339  * so far.
340  */
341 static const struct {
342 	u32 firmware_revision;
343 	u32 model;
344 	unsigned int workarounds;
345 } sbp2_workarounds_table[] = {
346 	/* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
347 		.firmware_revision	= 0x002800,
348 		.model			= 0x001010,
349 		.workarounds		= SBP2_WORKAROUND_INQUIRY_36 |
350 					  SBP2_WORKAROUND_MODE_SENSE_8 |
351 					  SBP2_WORKAROUND_POWER_CONDITION,
352 	},
353 	/* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
354 		.firmware_revision	= 0x002800,
355 		.model			= 0x000000,
356 		.workarounds		= SBP2_WORKAROUND_POWER_CONDITION,
357 	},
358 	/* Initio bridges, actually only needed for some older ones */ {
359 		.firmware_revision	= 0x000200,
360 		.model			= SBP2_ROM_VALUE_WILDCARD,
361 		.workarounds		= SBP2_WORKAROUND_INQUIRY_36,
362 	},
363 	/* PL-3507 bridge with Prolific firmware */ {
364 		.firmware_revision	= 0x012800,
365 		.model			= SBP2_ROM_VALUE_WILDCARD,
366 		.workarounds		= SBP2_WORKAROUND_POWER_CONDITION,
367 	},
368 	/* Symbios bridge */ {
369 		.firmware_revision	= 0xa0b800,
370 		.model			= SBP2_ROM_VALUE_WILDCARD,
371 		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS,
372 	},
373 	/* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
374 		.firmware_revision	= 0x002600,
375 		.model			= SBP2_ROM_VALUE_WILDCARD,
376 		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS,
377 	},
378 	/*
379 	 * iPod 2nd generation: needs 128k max transfer size workaround
380 	 * iPod 3rd generation: needs fix capacity workaround
381 	 */
382 	{
383 		.firmware_revision	= 0x0a2700,
384 		.model			= 0x000000,
385 		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS |
386 					  SBP2_WORKAROUND_FIX_CAPACITY,
387 	},
388 	/* iPod 4th generation */ {
389 		.firmware_revision	= 0x0a2700,
390 		.model			= 0x000021,
391 		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
392 	},
393 	/* iPod mini */ {
394 		.firmware_revision	= 0x0a2700,
395 		.model			= 0x000022,
396 		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
397 	},
398 	/* iPod mini */ {
399 		.firmware_revision	= 0x0a2700,
400 		.model			= 0x000023,
401 		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
402 	},
403 	/* iPod Photo */ {
404 		.firmware_revision	= 0x0a2700,
405 		.model			= 0x00007e,
406 		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
407 	}
408 };
409 
410 static void free_orb(struct kref *kref)
411 {
412 	struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
413 
414 	kfree(orb);
415 }
416 
417 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
418 			      int tcode, int destination, int source,
419 			      int generation, unsigned long long offset,
420 			      void *payload, size_t length, void *callback_data)
421 {
422 	struct sbp2_logical_unit *lu = callback_data;
423 	struct sbp2_orb *orb;
424 	struct sbp2_status status;
425 	unsigned long flags;
426 
427 	if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
428 	    length < 8 || length > sizeof(status)) {
429 		fw_send_response(card, request, RCODE_TYPE_ERROR);
430 		return;
431 	}
432 
433 	status.status  = be32_to_cpup(payload);
434 	status.orb_low = be32_to_cpup(payload + 4);
435 	memset(status.data, 0, sizeof(status.data));
436 	if (length > 8)
437 		memcpy(status.data, payload + 8, length - 8);
438 
439 	if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
440 		dev_notice(lu_dev(lu),
441 			   "non-ORB related status write, not handled\n");
442 		fw_send_response(card, request, RCODE_COMPLETE);
443 		return;
444 	}
445 
446 	/* Lookup the orb corresponding to this status write. */
447 	spin_lock_irqsave(&card->lock, flags);
448 	list_for_each_entry(orb, &lu->orb_list, link) {
449 		if (STATUS_GET_ORB_HIGH(status) == 0 &&
450 		    STATUS_GET_ORB_LOW(status) == orb->request_bus) {
451 			orb->rcode = RCODE_COMPLETE;
452 			list_del(&orb->link);
453 			break;
454 		}
455 	}
456 	spin_unlock_irqrestore(&card->lock, flags);
457 
458 	if (&orb->link != &lu->orb_list) {
459 		orb->callback(orb, &status);
460 		kref_put(&orb->kref, free_orb); /* orb callback reference */
461 	} else {
462 		dev_err(lu_dev(lu), "status write for unknown ORB\n");
463 	}
464 
465 	fw_send_response(card, request, RCODE_COMPLETE);
466 }
467 
468 static void complete_transaction(struct fw_card *card, int rcode,
469 				 void *payload, size_t length, void *data)
470 {
471 	struct sbp2_orb *orb = data;
472 	unsigned long flags;
473 
474 	/*
475 	 * This is a little tricky.  We can get the status write for
476 	 * the orb before we get this callback.  The status write
477 	 * handler above will assume the orb pointer transaction was
478 	 * successful and set the rcode to RCODE_COMPLETE for the orb.
479 	 * So this callback only sets the rcode if it hasn't already
480 	 * been set and only does the cleanup if the transaction
481 	 * failed and we didn't already get a status write.
482 	 */
483 	spin_lock_irqsave(&card->lock, flags);
484 
485 	if (orb->rcode == -1)
486 		orb->rcode = rcode;
487 	if (orb->rcode != RCODE_COMPLETE) {
488 		list_del(&orb->link);
489 		spin_unlock_irqrestore(&card->lock, flags);
490 
491 		orb->callback(orb, NULL);
492 		kref_put(&orb->kref, free_orb); /* orb callback reference */
493 	} else {
494 		spin_unlock_irqrestore(&card->lock, flags);
495 	}
496 
497 	kref_put(&orb->kref, free_orb); /* transaction callback reference */
498 }
499 
500 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
501 			  int node_id, int generation, u64 offset)
502 {
503 	struct fw_device *device = target_parent_device(lu->tgt);
504 	struct sbp2_pointer orb_pointer;
505 	unsigned long flags;
506 
507 	orb_pointer.high = 0;
508 	orb_pointer.low = cpu_to_be32(orb->request_bus);
509 
510 	spin_lock_irqsave(&device->card->lock, flags);
511 	list_add_tail(&orb->link, &lu->orb_list);
512 	spin_unlock_irqrestore(&device->card->lock, flags);
513 
514 	kref_get(&orb->kref); /* transaction callback reference */
515 	kref_get(&orb->kref); /* orb callback reference */
516 
517 	fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
518 			node_id, generation, device->max_speed, offset,
519 			&orb_pointer, 8, complete_transaction, orb);
520 }
521 
522 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
523 {
524 	struct fw_device *device = target_parent_device(lu->tgt);
525 	struct sbp2_orb *orb, *next;
526 	struct list_head list;
527 	unsigned long flags;
528 	int retval = -ENOENT;
529 
530 	INIT_LIST_HEAD(&list);
531 	spin_lock_irqsave(&device->card->lock, flags);
532 	list_splice_init(&lu->orb_list, &list);
533 	spin_unlock_irqrestore(&device->card->lock, flags);
534 
535 	list_for_each_entry_safe(orb, next, &list, link) {
536 		retval = 0;
537 		if (fw_cancel_transaction(device->card, &orb->t) == 0)
538 			continue;
539 
540 		orb->rcode = RCODE_CANCELLED;
541 		orb->callback(orb, NULL);
542 		kref_put(&orb->kref, free_orb); /* orb callback reference */
543 	}
544 
545 	return retval;
546 }
547 
548 static void complete_management_orb(struct sbp2_orb *base_orb,
549 				    struct sbp2_status *status)
550 {
551 	struct sbp2_management_orb *orb =
552 		container_of(base_orb, struct sbp2_management_orb, base);
553 
554 	if (status)
555 		memcpy(&orb->status, status, sizeof(*status));
556 	complete(&orb->done);
557 }
558 
559 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
560 				    int generation, int function,
561 				    int lun_or_login_id, void *response)
562 {
563 	struct fw_device *device = target_parent_device(lu->tgt);
564 	struct sbp2_management_orb *orb;
565 	unsigned int timeout;
566 	int retval = -ENOMEM;
567 
568 	if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
569 		return 0;
570 
571 	orb = kzalloc(sizeof(*orb), GFP_NOIO);
572 	if (orb == NULL)
573 		return -ENOMEM;
574 
575 	kref_init(&orb->base.kref);
576 	orb->response_bus =
577 		dma_map_single(device->card->device, &orb->response,
578 			       sizeof(orb->response), DMA_FROM_DEVICE);
579 	if (dma_mapping_error(device->card->device, orb->response_bus))
580 		goto fail_mapping_response;
581 
582 	orb->request.response.high = 0;
583 	orb->request.response.low  = cpu_to_be32(orb->response_bus);
584 
585 	orb->request.misc = cpu_to_be32(
586 		MANAGEMENT_ORB_NOTIFY |
587 		MANAGEMENT_ORB_FUNCTION(function) |
588 		MANAGEMENT_ORB_LUN(lun_or_login_id));
589 	orb->request.length = cpu_to_be32(
590 		MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
591 
592 	orb->request.status_fifo.high =
593 		cpu_to_be32(lu->address_handler.offset >> 32);
594 	orb->request.status_fifo.low  =
595 		cpu_to_be32(lu->address_handler.offset);
596 
597 	if (function == SBP2_LOGIN_REQUEST) {
598 		/* Ask for 2^2 == 4 seconds reconnect grace period */
599 		orb->request.misc |= cpu_to_be32(
600 			MANAGEMENT_ORB_RECONNECT(2) |
601 			MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
602 		timeout = lu->tgt->mgt_orb_timeout;
603 	} else {
604 		timeout = SBP2_ORB_TIMEOUT;
605 	}
606 
607 	init_completion(&orb->done);
608 	orb->base.callback = complete_management_orb;
609 
610 	orb->base.request_bus =
611 		dma_map_single(device->card->device, &orb->request,
612 			       sizeof(orb->request), DMA_TO_DEVICE);
613 	if (dma_mapping_error(device->card->device, orb->base.request_bus))
614 		goto fail_mapping_request;
615 
616 	sbp2_send_orb(&orb->base, lu, node_id, generation,
617 		      lu->tgt->management_agent_address);
618 
619 	wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
620 
621 	retval = -EIO;
622 	if (sbp2_cancel_orbs(lu) == 0) {
623 		dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
624 			orb->base.rcode);
625 		goto out;
626 	}
627 
628 	if (orb->base.rcode != RCODE_COMPLETE) {
629 		dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
630 			orb->base.rcode);
631 		goto out;
632 	}
633 
634 	if (STATUS_GET_RESPONSE(orb->status) != 0 ||
635 	    STATUS_GET_SBP_STATUS(orb->status) != 0) {
636 		dev_err(lu_dev(lu), "error status: %d:%d\n",
637 			 STATUS_GET_RESPONSE(orb->status),
638 			 STATUS_GET_SBP_STATUS(orb->status));
639 		goto out;
640 	}
641 
642 	retval = 0;
643  out:
644 	dma_unmap_single(device->card->device, orb->base.request_bus,
645 			 sizeof(orb->request), DMA_TO_DEVICE);
646  fail_mapping_request:
647 	dma_unmap_single(device->card->device, orb->response_bus,
648 			 sizeof(orb->response), DMA_FROM_DEVICE);
649  fail_mapping_response:
650 	if (response)
651 		memcpy(response, orb->response, sizeof(orb->response));
652 	kref_put(&orb->base.kref, free_orb);
653 
654 	return retval;
655 }
656 
657 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
658 {
659 	struct fw_device *device = target_parent_device(lu->tgt);
660 	__be32 d = 0;
661 
662 	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
663 			   lu->tgt->node_id, lu->generation, device->max_speed,
664 			   lu->command_block_agent_address + SBP2_AGENT_RESET,
665 			   &d, 4);
666 }
667 
668 static void complete_agent_reset_write_no_wait(struct fw_card *card,
669 		int rcode, void *payload, size_t length, void *data)
670 {
671 	kfree(data);
672 }
673 
674 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
675 {
676 	struct fw_device *device = target_parent_device(lu->tgt);
677 	struct fw_transaction *t;
678 	static __be32 d;
679 
680 	t = kmalloc(sizeof(*t), GFP_ATOMIC);
681 	if (t == NULL)
682 		return;
683 
684 	fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
685 			lu->tgt->node_id, lu->generation, device->max_speed,
686 			lu->command_block_agent_address + SBP2_AGENT_RESET,
687 			&d, 4, complete_agent_reset_write_no_wait, t);
688 }
689 
690 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
691 {
692 	/*
693 	 * We may access dont_block without taking card->lock here:
694 	 * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
695 	 * are currently serialized against each other.
696 	 * And a wrong result in sbp2_conditionally_block()'s access of
697 	 * dont_block is rather harmless, it simply misses its first chance.
698 	 */
699 	--lu->tgt->dont_block;
700 }
701 
702 /*
703  * Blocks lu->tgt if all of the following conditions are met:
704  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
705  *     logical units have been finished (indicated by dont_block == 0).
706  *   - lu->generation is stale.
707  *
708  * Note, scsi_block_requests() must be called while holding card->lock,
709  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
710  * unblock the target.
711  */
712 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
713 {
714 	struct sbp2_target *tgt = lu->tgt;
715 	struct fw_card *card = target_parent_device(tgt)->card;
716 	struct Scsi_Host *shost =
717 		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
718 	unsigned long flags;
719 
720 	spin_lock_irqsave(&card->lock, flags);
721 	if (!tgt->dont_block && !lu->blocked &&
722 	    lu->generation != card->generation) {
723 		lu->blocked = true;
724 		if (++tgt->blocked == 1)
725 			scsi_block_requests(shost);
726 	}
727 	spin_unlock_irqrestore(&card->lock, flags);
728 }
729 
730 /*
731  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
732  * Note, it is harmless to run scsi_unblock_requests() outside the
733  * card->lock protected section.  On the other hand, running it inside
734  * the section might clash with shost->host_lock.
735  */
736 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
737 {
738 	struct sbp2_target *tgt = lu->tgt;
739 	struct fw_card *card = target_parent_device(tgt)->card;
740 	struct Scsi_Host *shost =
741 		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
742 	unsigned long flags;
743 	bool unblock = false;
744 
745 	spin_lock_irqsave(&card->lock, flags);
746 	if (lu->blocked && lu->generation == card->generation) {
747 		lu->blocked = false;
748 		unblock = --tgt->blocked == 0;
749 	}
750 	spin_unlock_irqrestore(&card->lock, flags);
751 
752 	if (unblock)
753 		scsi_unblock_requests(shost);
754 }
755 
756 /*
757  * Prevents future blocking of tgt and unblocks it.
758  * Note, it is harmless to run scsi_unblock_requests() outside the
759  * card->lock protected section.  On the other hand, running it inside
760  * the section might clash with shost->host_lock.
761  */
762 static void sbp2_unblock(struct sbp2_target *tgt)
763 {
764 	struct fw_card *card = target_parent_device(tgt)->card;
765 	struct Scsi_Host *shost =
766 		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
767 	unsigned long flags;
768 
769 	spin_lock_irqsave(&card->lock, flags);
770 	++tgt->dont_block;
771 	spin_unlock_irqrestore(&card->lock, flags);
772 
773 	scsi_unblock_requests(shost);
774 }
775 
776 static int sbp2_lun2int(u16 lun)
777 {
778 	struct scsi_lun eight_bytes_lun;
779 
780 	memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
781 	eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
782 	eight_bytes_lun.scsi_lun[1] = lun & 0xff;
783 
784 	return scsilun_to_int(&eight_bytes_lun);
785 }
786 
787 /*
788  * Write retransmit retry values into the BUSY_TIMEOUT register.
789  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
790  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
791  *   saner value after logging into the device.
792  * - The dual-phase retry protocol is optional to implement, and if not
793  *   supported, writes to the dual-phase portion of the register will be
794  *   ignored. We try to write the original 1394-1995 default here.
795  * - In the case of devices that are also SBP-3-compliant, all writes are
796  *   ignored, as the register is read-only, but contains single-phase retry of
797  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
798  *   write attempt is safe and yields more consistent behavior for all devices.
799  *
800  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
801  * and section 6.4 of the SBP-3 spec for further details.
802  */
803 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
804 {
805 	struct fw_device *device = target_parent_device(lu->tgt);
806 	__be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
807 
808 	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
809 			   lu->tgt->node_id, lu->generation, device->max_speed,
810 			   CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
811 }
812 
813 static void sbp2_reconnect(struct work_struct *work);
814 
815 static void sbp2_login(struct work_struct *work)
816 {
817 	struct sbp2_logical_unit *lu =
818 		container_of(work, struct sbp2_logical_unit, work.work);
819 	struct sbp2_target *tgt = lu->tgt;
820 	struct fw_device *device = target_parent_device(tgt);
821 	struct Scsi_Host *shost;
822 	struct scsi_device *sdev;
823 	struct sbp2_login_response response;
824 	int generation, node_id, local_node_id;
825 
826 	if (fw_device_is_shutdown(device))
827 		return;
828 
829 	generation    = device->generation;
830 	smp_rmb();    /* node IDs must not be older than generation */
831 	node_id       = device->node_id;
832 	local_node_id = device->card->node_id;
833 
834 	/* If this is a re-login attempt, log out, or we might be rejected. */
835 	if (lu->has_sdev)
836 		sbp2_send_management_orb(lu, device->node_id, generation,
837 				SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
838 
839 	if (sbp2_send_management_orb(lu, node_id, generation,
840 				SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
841 		if (lu->retries++ < 5) {
842 			sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
843 		} else {
844 			dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
845 				lu->lun);
846 			/* Let any waiting I/O fail from now on. */
847 			sbp2_unblock(lu->tgt);
848 		}
849 		return;
850 	}
851 
852 	tgt->node_id	  = node_id;
853 	tgt->address_high = local_node_id << 16;
854 	smp_wmb();	  /* node IDs must not be older than generation */
855 	lu->generation	  = generation;
856 
857 	lu->command_block_agent_address =
858 		((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
859 		      << 32) | be32_to_cpu(response.command_block_agent.low);
860 	lu->login_id = be32_to_cpu(response.misc) & 0xffff;
861 
862 	dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
863 		   lu->lun, lu->retries);
864 
865 	/* set appropriate retry limit(s) in BUSY_TIMEOUT register */
866 	sbp2_set_busy_timeout(lu);
867 
868 	lu->workfn = sbp2_reconnect;
869 	sbp2_agent_reset(lu);
870 
871 	/* This was a re-login. */
872 	if (lu->has_sdev) {
873 		sbp2_cancel_orbs(lu);
874 		sbp2_conditionally_unblock(lu);
875 
876 		return;
877 	}
878 
879 	if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
880 		ssleep(SBP2_INQUIRY_DELAY);
881 
882 	shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
883 	sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
884 	/*
885 	 * FIXME:  We are unable to perform reconnects while in sbp2_login().
886 	 * Therefore __scsi_add_device() will get into trouble if a bus reset
887 	 * happens in parallel.  It will either fail or leave us with an
888 	 * unusable sdev.  As a workaround we check for this and retry the
889 	 * whole login and SCSI probing.
890 	 */
891 
892 	/* Reported error during __scsi_add_device() */
893 	if (IS_ERR(sdev))
894 		goto out_logout_login;
895 
896 	/* Unreported error during __scsi_add_device() */
897 	smp_rmb(); /* get current card generation */
898 	if (generation != device->card->generation) {
899 		scsi_remove_device(sdev);
900 		scsi_device_put(sdev);
901 		goto out_logout_login;
902 	}
903 
904 	/* No error during __scsi_add_device() */
905 	lu->has_sdev = true;
906 	scsi_device_put(sdev);
907 	sbp2_allow_block(lu);
908 
909 	return;
910 
911  out_logout_login:
912 	smp_rmb(); /* generation may have changed */
913 	generation = device->generation;
914 	smp_rmb(); /* node_id must not be older than generation */
915 
916 	sbp2_send_management_orb(lu, device->node_id, generation,
917 				 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
918 	/*
919 	 * If a bus reset happened, sbp2_update will have requeued
920 	 * lu->work already.  Reset the work from reconnect to login.
921 	 */
922 	lu->workfn = sbp2_login;
923 }
924 
925 static void sbp2_reconnect(struct work_struct *work)
926 {
927 	struct sbp2_logical_unit *lu =
928 		container_of(work, struct sbp2_logical_unit, work.work);
929 	struct sbp2_target *tgt = lu->tgt;
930 	struct fw_device *device = target_parent_device(tgt);
931 	int generation, node_id, local_node_id;
932 
933 	if (fw_device_is_shutdown(device))
934 		return;
935 
936 	generation    = device->generation;
937 	smp_rmb();    /* node IDs must not be older than generation */
938 	node_id       = device->node_id;
939 	local_node_id = device->card->node_id;
940 
941 	if (sbp2_send_management_orb(lu, node_id, generation,
942 				     SBP2_RECONNECT_REQUEST,
943 				     lu->login_id, NULL) < 0) {
944 		/*
945 		 * If reconnect was impossible even though we are in the
946 		 * current generation, fall back and try to log in again.
947 		 *
948 		 * We could check for "Function rejected" status, but
949 		 * looking at the bus generation as simpler and more general.
950 		 */
951 		smp_rmb(); /* get current card generation */
952 		if (generation == device->card->generation ||
953 		    lu->retries++ >= 5) {
954 			dev_err(tgt_dev(tgt), "failed to reconnect\n");
955 			lu->retries = 0;
956 			lu->workfn = sbp2_login;
957 		}
958 		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
959 
960 		return;
961 	}
962 
963 	tgt->node_id      = node_id;
964 	tgt->address_high = local_node_id << 16;
965 	smp_wmb();	  /* node IDs must not be older than generation */
966 	lu->generation	  = generation;
967 
968 	dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
969 		   lu->lun, lu->retries);
970 
971 	sbp2_agent_reset(lu);
972 	sbp2_cancel_orbs(lu);
973 	sbp2_conditionally_unblock(lu);
974 }
975 
976 static void sbp2_lu_workfn(struct work_struct *work)
977 {
978 	struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
979 						struct sbp2_logical_unit, work);
980 	lu->workfn(work);
981 }
982 
983 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
984 {
985 	struct sbp2_logical_unit *lu;
986 
987 	lu = kmalloc(sizeof(*lu), GFP_KERNEL);
988 	if (!lu)
989 		return -ENOMEM;
990 
991 	lu->address_handler.length           = 0x100;
992 	lu->address_handler.address_callback = sbp2_status_write;
993 	lu->address_handler.callback_data    = lu;
994 
995 	if (fw_core_add_address_handler(&lu->address_handler,
996 					&fw_high_memory_region) < 0) {
997 		kfree(lu);
998 		return -ENOMEM;
999 	}
1000 
1001 	lu->tgt      = tgt;
1002 	lu->lun      = lun_entry & 0xffff;
1003 	lu->login_id = INVALID_LOGIN_ID;
1004 	lu->retries  = 0;
1005 	lu->has_sdev = false;
1006 	lu->blocked  = false;
1007 	++tgt->dont_block;
1008 	INIT_LIST_HEAD(&lu->orb_list);
1009 	lu->workfn = sbp2_login;
1010 	INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
1011 
1012 	list_add_tail(&lu->link, &tgt->lu_list);
1013 	return 0;
1014 }
1015 
1016 static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
1017 				    const u32 *leaf)
1018 {
1019 	if ((leaf[0] & 0xffff0000) == 0x00020000)
1020 		tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1021 }
1022 
1023 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1024 				      const u32 *directory)
1025 {
1026 	struct fw_csr_iterator ci;
1027 	int key, value;
1028 
1029 	fw_csr_iterator_init(&ci, directory);
1030 	while (fw_csr_iterator_next(&ci, &key, &value))
1031 		if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1032 		    sbp2_add_logical_unit(tgt, value) < 0)
1033 			return -ENOMEM;
1034 	return 0;
1035 }
1036 
1037 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1038 			      u32 *model, u32 *firmware_revision)
1039 {
1040 	struct fw_csr_iterator ci;
1041 	int key, value;
1042 
1043 	fw_csr_iterator_init(&ci, directory);
1044 	while (fw_csr_iterator_next(&ci, &key, &value)) {
1045 		switch (key) {
1046 
1047 		case CSR_DEPENDENT_INFO | CSR_OFFSET:
1048 			tgt->management_agent_address =
1049 					CSR_REGISTER_BASE + 4 * value;
1050 			break;
1051 
1052 		case CSR_DIRECTORY_ID:
1053 			tgt->directory_id = value;
1054 			break;
1055 
1056 		case CSR_MODEL:
1057 			*model = value;
1058 			break;
1059 
1060 		case SBP2_CSR_FIRMWARE_REVISION:
1061 			*firmware_revision = value;
1062 			break;
1063 
1064 		case SBP2_CSR_UNIT_CHARACTERISTICS:
1065 			/* the timeout value is stored in 500ms units */
1066 			tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1067 			break;
1068 
1069 		case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1070 			if (sbp2_add_logical_unit(tgt, value) < 0)
1071 				return -ENOMEM;
1072 			break;
1073 
1074 		case SBP2_CSR_UNIT_UNIQUE_ID:
1075 			sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1076 			break;
1077 
1078 		case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1079 			/* Adjust for the increment in the iterator */
1080 			if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1081 				return -ENOMEM;
1082 			break;
1083 		}
1084 	}
1085 	return 0;
1086 }
1087 
1088 /*
1089  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1090  * provided in the config rom. Most devices do provide a value, which
1091  * we'll use for login management orbs, but with some sane limits.
1092  */
1093 static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1094 {
1095 	unsigned int timeout = tgt->mgt_orb_timeout;
1096 
1097 	if (timeout > 40000)
1098 		dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1099 			   timeout / 1000);
1100 
1101 	tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1102 }
1103 
1104 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1105 				  u32 firmware_revision)
1106 {
1107 	int i;
1108 	unsigned int w = sbp2_param_workarounds;
1109 
1110 	if (w)
1111 		dev_notice(tgt_dev(tgt),
1112 			   "Please notify linux1394-devel@lists.sf.net "
1113 			   "if you need the workarounds parameter\n");
1114 
1115 	if (w & SBP2_WORKAROUND_OVERRIDE)
1116 		goto out;
1117 
1118 	for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1119 
1120 		if (sbp2_workarounds_table[i].firmware_revision !=
1121 		    (firmware_revision & 0xffffff00))
1122 			continue;
1123 
1124 		if (sbp2_workarounds_table[i].model != model &&
1125 		    sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1126 			continue;
1127 
1128 		w |= sbp2_workarounds_table[i].workarounds;
1129 		break;
1130 	}
1131  out:
1132 	if (w)
1133 		dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1134 			   "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1135 			   w, firmware_revision, model);
1136 	tgt->workarounds = w;
1137 }
1138 
1139 static struct scsi_host_template scsi_driver_template;
1140 static void sbp2_remove(struct fw_unit *unit);
1141 
1142 static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
1143 {
1144 	struct fw_device *device = fw_parent_device(unit);
1145 	struct sbp2_target *tgt;
1146 	struct sbp2_logical_unit *lu;
1147 	struct Scsi_Host *shost;
1148 	u32 model, firmware_revision;
1149 
1150 	/* cannot (or should not) handle targets on the local node */
1151 	if (device->is_local)
1152 		return -ENODEV;
1153 
1154 	if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1155 		WARN_ON(dma_set_max_seg_size(device->card->device,
1156 					     SBP2_MAX_SEG_SIZE));
1157 
1158 	shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1159 	if (shost == NULL)
1160 		return -ENOMEM;
1161 
1162 	tgt = (struct sbp2_target *)shost->hostdata;
1163 	dev_set_drvdata(&unit->device, tgt);
1164 	tgt->unit = unit;
1165 	INIT_LIST_HEAD(&tgt->lu_list);
1166 	tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1167 
1168 	if (fw_device_enable_phys_dma(device) < 0)
1169 		goto fail_shost_put;
1170 
1171 	shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1172 
1173 	if (scsi_add_host_with_dma(shost, &unit->device,
1174 				   device->card->device) < 0)
1175 		goto fail_shost_put;
1176 
1177 	/* implicit directory ID */
1178 	tgt->directory_id = ((unit->directory - device->config_rom) * 4
1179 			     + CSR_CONFIG_ROM) & 0xffffff;
1180 
1181 	firmware_revision = SBP2_ROM_VALUE_MISSING;
1182 	model		  = SBP2_ROM_VALUE_MISSING;
1183 
1184 	if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1185 			       &firmware_revision) < 0)
1186 		goto fail_remove;
1187 
1188 	sbp2_clamp_management_orb_timeout(tgt);
1189 	sbp2_init_workarounds(tgt, model, firmware_revision);
1190 
1191 	/*
1192 	 * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1193 	 * and so on up to 4096 bytes.  The SBP-2 max_payload field
1194 	 * specifies the max payload size as 2 ^ (max_payload + 2), so
1195 	 * if we set this to max_speed + 7, we get the right value.
1196 	 */
1197 	tgt->max_payload = min3(device->max_speed + 7, 10U,
1198 				device->card->max_receive - 1);
1199 
1200 	/* Do the login in a workqueue so we can easily reschedule retries. */
1201 	list_for_each_entry(lu, &tgt->lu_list, link)
1202 		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1203 
1204 	return 0;
1205 
1206  fail_remove:
1207 	sbp2_remove(unit);
1208 	return -ENOMEM;
1209 
1210  fail_shost_put:
1211 	scsi_host_put(shost);
1212 	return -ENOMEM;
1213 }
1214 
1215 static void sbp2_update(struct fw_unit *unit)
1216 {
1217 	struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1218 	struct sbp2_logical_unit *lu;
1219 
1220 	fw_device_enable_phys_dma(fw_parent_device(unit));
1221 
1222 	/*
1223 	 * Fw-core serializes sbp2_update() against sbp2_remove().
1224 	 * Iteration over tgt->lu_list is therefore safe here.
1225 	 */
1226 	list_for_each_entry(lu, &tgt->lu_list, link) {
1227 		sbp2_conditionally_block(lu);
1228 		lu->retries = 0;
1229 		sbp2_queue_work(lu, 0);
1230 	}
1231 }
1232 
1233 static void sbp2_remove(struct fw_unit *unit)
1234 {
1235 	struct fw_device *device = fw_parent_device(unit);
1236 	struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1237 	struct sbp2_logical_unit *lu, *next;
1238 	struct Scsi_Host *shost =
1239 		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1240 	struct scsi_device *sdev;
1241 
1242 	/* prevent deadlocks */
1243 	sbp2_unblock(tgt);
1244 
1245 	list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1246 		cancel_delayed_work_sync(&lu->work);
1247 		sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1248 		if (sdev) {
1249 			scsi_remove_device(sdev);
1250 			scsi_device_put(sdev);
1251 		}
1252 		if (lu->login_id != INVALID_LOGIN_ID) {
1253 			int generation, node_id;
1254 			/*
1255 			 * tgt->node_id may be obsolete here if we failed
1256 			 * during initial login or after a bus reset where
1257 			 * the topology changed.
1258 			 */
1259 			generation = device->generation;
1260 			smp_rmb(); /* node_id vs. generation */
1261 			node_id    = device->node_id;
1262 			sbp2_send_management_orb(lu, node_id, generation,
1263 						 SBP2_LOGOUT_REQUEST,
1264 						 lu->login_id, NULL);
1265 		}
1266 		fw_core_remove_address_handler(&lu->address_handler);
1267 		list_del(&lu->link);
1268 		kfree(lu);
1269 	}
1270 	scsi_remove_host(shost);
1271 	dev_notice(&unit->device, "released target %d:0:0\n", shost->host_no);
1272 
1273 	scsi_host_put(shost);
1274 }
1275 
1276 #define SBP2_UNIT_SPEC_ID_ENTRY	0x0000609e
1277 #define SBP2_SW_VERSION_ENTRY	0x00010483
1278 
1279 static const struct ieee1394_device_id sbp2_id_table[] = {
1280 	{
1281 		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1282 				IEEE1394_MATCH_VERSION,
1283 		.specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1284 		.version      = SBP2_SW_VERSION_ENTRY,
1285 	},
1286 	{ }
1287 };
1288 
1289 static struct fw_driver sbp2_driver = {
1290 	.driver   = {
1291 		.owner  = THIS_MODULE,
1292 		.name   = KBUILD_MODNAME,
1293 		.bus    = &fw_bus_type,
1294 	},
1295 	.probe    = sbp2_probe,
1296 	.update   = sbp2_update,
1297 	.remove   = sbp2_remove,
1298 	.id_table = sbp2_id_table,
1299 };
1300 
1301 static void sbp2_unmap_scatterlist(struct device *card_device,
1302 				   struct sbp2_command_orb *orb)
1303 {
1304 	scsi_dma_unmap(orb->cmd);
1305 
1306 	if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1307 		dma_unmap_single(card_device, orb->page_table_bus,
1308 				 sizeof(orb->page_table), DMA_TO_DEVICE);
1309 }
1310 
1311 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1312 {
1313 	int sam_status;
1314 	int sfmt = (sbp2_status[0] >> 6) & 0x03;
1315 
1316 	if (sfmt == 2 || sfmt == 3) {
1317 		/*
1318 		 * Reserved for future standardization (2) or
1319 		 * Status block format vendor-dependent (3)
1320 		 */
1321 		return DID_ERROR << 16;
1322 	}
1323 
1324 	sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1325 	sense_data[1] = 0x0;
1326 	sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1327 	sense_data[3] = sbp2_status[4];
1328 	sense_data[4] = sbp2_status[5];
1329 	sense_data[5] = sbp2_status[6];
1330 	sense_data[6] = sbp2_status[7];
1331 	sense_data[7] = 10;
1332 	sense_data[8] = sbp2_status[8];
1333 	sense_data[9] = sbp2_status[9];
1334 	sense_data[10] = sbp2_status[10];
1335 	sense_data[11] = sbp2_status[11];
1336 	sense_data[12] = sbp2_status[2];
1337 	sense_data[13] = sbp2_status[3];
1338 	sense_data[14] = sbp2_status[12];
1339 	sense_data[15] = sbp2_status[13];
1340 
1341 	sam_status = sbp2_status[0] & 0x3f;
1342 
1343 	switch (sam_status) {
1344 	case SAM_STAT_GOOD:
1345 	case SAM_STAT_CHECK_CONDITION:
1346 	case SAM_STAT_CONDITION_MET:
1347 	case SAM_STAT_BUSY:
1348 	case SAM_STAT_RESERVATION_CONFLICT:
1349 	case SAM_STAT_COMMAND_TERMINATED:
1350 		return DID_OK << 16 | sam_status;
1351 
1352 	default:
1353 		return DID_ERROR << 16;
1354 	}
1355 }
1356 
1357 static void complete_command_orb(struct sbp2_orb *base_orb,
1358 				 struct sbp2_status *status)
1359 {
1360 	struct sbp2_command_orb *orb =
1361 		container_of(base_orb, struct sbp2_command_orb, base);
1362 	struct fw_device *device = target_parent_device(orb->lu->tgt);
1363 	int result;
1364 
1365 	if (status != NULL) {
1366 		if (STATUS_GET_DEAD(*status))
1367 			sbp2_agent_reset_no_wait(orb->lu);
1368 
1369 		switch (STATUS_GET_RESPONSE(*status)) {
1370 		case SBP2_STATUS_REQUEST_COMPLETE:
1371 			result = DID_OK << 16;
1372 			break;
1373 		case SBP2_STATUS_TRANSPORT_FAILURE:
1374 			result = DID_BUS_BUSY << 16;
1375 			break;
1376 		case SBP2_STATUS_ILLEGAL_REQUEST:
1377 		case SBP2_STATUS_VENDOR_DEPENDENT:
1378 		default:
1379 			result = DID_ERROR << 16;
1380 			break;
1381 		}
1382 
1383 		if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1384 			result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1385 							   orb->cmd->sense_buffer);
1386 	} else {
1387 		/*
1388 		 * If the orb completes with status == NULL, something
1389 		 * went wrong, typically a bus reset happened mid-orb
1390 		 * or when sending the write (less likely).
1391 		 */
1392 		result = DID_BUS_BUSY << 16;
1393 		sbp2_conditionally_block(orb->lu);
1394 	}
1395 
1396 	dma_unmap_single(device->card->device, orb->base.request_bus,
1397 			 sizeof(orb->request), DMA_TO_DEVICE);
1398 	sbp2_unmap_scatterlist(device->card->device, orb);
1399 
1400 	orb->cmd->result = result;
1401 	orb->cmd->scsi_done(orb->cmd);
1402 }
1403 
1404 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1405 		struct fw_device *device, struct sbp2_logical_unit *lu)
1406 {
1407 	struct scatterlist *sg = scsi_sglist(orb->cmd);
1408 	int i, n;
1409 
1410 	n = scsi_dma_map(orb->cmd);
1411 	if (n <= 0)
1412 		goto fail;
1413 
1414 	/*
1415 	 * Handle the special case where there is only one element in
1416 	 * the scatter list by converting it to an immediate block
1417 	 * request. This is also a workaround for broken devices such
1418 	 * as the second generation iPod which doesn't support page
1419 	 * tables.
1420 	 */
1421 	if (n == 1) {
1422 		orb->request.data_descriptor.high =
1423 			cpu_to_be32(lu->tgt->address_high);
1424 		orb->request.data_descriptor.low  =
1425 			cpu_to_be32(sg_dma_address(sg));
1426 		orb->request.misc |=
1427 			cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1428 		return 0;
1429 	}
1430 
1431 	for_each_sg(sg, sg, n, i) {
1432 		orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1433 		orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1434 	}
1435 
1436 	orb->page_table_bus =
1437 		dma_map_single(device->card->device, orb->page_table,
1438 			       sizeof(orb->page_table), DMA_TO_DEVICE);
1439 	if (dma_mapping_error(device->card->device, orb->page_table_bus))
1440 		goto fail_page_table;
1441 
1442 	/*
1443 	 * The data_descriptor pointer is the one case where we need
1444 	 * to fill in the node ID part of the address.  All other
1445 	 * pointers assume that the data referenced reside on the
1446 	 * initiator (i.e. us), but data_descriptor can refer to data
1447 	 * on other nodes so we need to put our ID in descriptor.high.
1448 	 */
1449 	orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1450 	orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1451 	orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1452 					 COMMAND_ORB_DATA_SIZE(n));
1453 
1454 	return 0;
1455 
1456  fail_page_table:
1457 	scsi_dma_unmap(orb->cmd);
1458  fail:
1459 	return -ENOMEM;
1460 }
1461 
1462 /* SCSI stack integration */
1463 
1464 static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1465 				  struct scsi_cmnd *cmd)
1466 {
1467 	struct sbp2_logical_unit *lu = cmd->device->hostdata;
1468 	struct fw_device *device = target_parent_device(lu->tgt);
1469 	struct sbp2_command_orb *orb;
1470 	int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1471 
1472 	/*
1473 	 * Bidirectional commands are not yet implemented, and unknown
1474 	 * transfer direction not handled.
1475 	 */
1476 	if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1477 		dev_err(lu_dev(lu), "cannot handle bidirectional command\n");
1478 		cmd->result = DID_ERROR << 16;
1479 		cmd->scsi_done(cmd);
1480 		return 0;
1481 	}
1482 
1483 	orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1484 	if (orb == NULL)
1485 		return SCSI_MLQUEUE_HOST_BUSY;
1486 
1487 	/* Initialize rcode to something not RCODE_COMPLETE. */
1488 	orb->base.rcode = -1;
1489 	kref_init(&orb->base.kref);
1490 	orb->lu = lu;
1491 	orb->cmd = cmd;
1492 	orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1493 	orb->request.misc = cpu_to_be32(
1494 		COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1495 		COMMAND_ORB_SPEED(device->max_speed) |
1496 		COMMAND_ORB_NOTIFY);
1497 
1498 	if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1499 		orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1500 
1501 	generation = device->generation;
1502 	smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1503 
1504 	if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1505 		goto out;
1506 
1507 	memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1508 
1509 	orb->base.callback = complete_command_orb;
1510 	orb->base.request_bus =
1511 		dma_map_single(device->card->device, &orb->request,
1512 			       sizeof(orb->request), DMA_TO_DEVICE);
1513 	if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1514 		sbp2_unmap_scatterlist(device->card->device, orb);
1515 		goto out;
1516 	}
1517 
1518 	sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1519 		      lu->command_block_agent_address + SBP2_ORB_POINTER);
1520 	retval = 0;
1521  out:
1522 	kref_put(&orb->base.kref, free_orb);
1523 	return retval;
1524 }
1525 
1526 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1527 {
1528 	struct sbp2_logical_unit *lu = sdev->hostdata;
1529 
1530 	/* (Re-)Adding logical units via the SCSI stack is not supported. */
1531 	if (!lu)
1532 		return -ENOSYS;
1533 
1534 	sdev->allow_restart = 1;
1535 
1536 	/*
1537 	 * SBP-2 does not require any alignment, but we set it anyway
1538 	 * for compatibility with earlier versions of this driver.
1539 	 */
1540 	blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1541 
1542 	if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1543 		sdev->inquiry_len = 36;
1544 
1545 	return 0;
1546 }
1547 
1548 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1549 {
1550 	struct sbp2_logical_unit *lu = sdev->hostdata;
1551 
1552 	sdev->use_10_for_rw = 1;
1553 
1554 	if (sbp2_param_exclusive_login)
1555 		sdev->manage_start_stop = 1;
1556 
1557 	if (sdev->type == TYPE_ROM)
1558 		sdev->use_10_for_ms = 1;
1559 
1560 	if (sdev->type == TYPE_DISK &&
1561 	    lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1562 		sdev->skip_ms_page_8 = 1;
1563 
1564 	if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1565 		sdev->fix_capacity = 1;
1566 
1567 	if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1568 		sdev->start_stop_pwr_cond = 1;
1569 
1570 	if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1571 		blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1572 
1573 	return 0;
1574 }
1575 
1576 /*
1577  * Called by scsi stack when something has really gone wrong.  Usually
1578  * called when a command has timed-out for some reason.
1579  */
1580 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1581 {
1582 	struct sbp2_logical_unit *lu = cmd->device->hostdata;
1583 
1584 	dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1585 	sbp2_agent_reset(lu);
1586 	sbp2_cancel_orbs(lu);
1587 
1588 	return SUCCESS;
1589 }
1590 
1591 /*
1592  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1593  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1594  *
1595  * This is the concatenation of target port identifier and logical unit
1596  * identifier as per SAM-2...SAM-4 annex A.
1597  */
1598 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1599 			struct device_attribute *attr, char *buf)
1600 {
1601 	struct scsi_device *sdev = to_scsi_device(dev);
1602 	struct sbp2_logical_unit *lu;
1603 
1604 	if (!sdev)
1605 		return 0;
1606 
1607 	lu = sdev->hostdata;
1608 
1609 	return sprintf(buf, "%016llx:%06x:%04x\n",
1610 			(unsigned long long)lu->tgt->guid,
1611 			lu->tgt->directory_id, lu->lun);
1612 }
1613 
1614 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1615 
1616 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1617 	&dev_attr_ieee1394_id,
1618 	NULL
1619 };
1620 
1621 static struct scsi_host_template scsi_driver_template = {
1622 	.module			= THIS_MODULE,
1623 	.name			= "SBP-2 IEEE-1394",
1624 	.proc_name		= "sbp2",
1625 	.queuecommand		= sbp2_scsi_queuecommand,
1626 	.slave_alloc		= sbp2_scsi_slave_alloc,
1627 	.slave_configure	= sbp2_scsi_slave_configure,
1628 	.eh_abort_handler	= sbp2_scsi_abort,
1629 	.this_id		= -1,
1630 	.sg_tablesize		= SG_ALL,
1631 	.use_clustering		= ENABLE_CLUSTERING,
1632 	.cmd_per_lun		= 1,
1633 	.can_queue		= 1,
1634 	.sdev_attrs		= sbp2_scsi_sysfs_attrs,
1635 };
1636 
1637 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1638 MODULE_DESCRIPTION("SCSI over IEEE1394");
1639 MODULE_LICENSE("GPL");
1640 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1641 
1642 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1643 MODULE_ALIAS("sbp2");
1644 
1645 static int __init sbp2_init(void)
1646 {
1647 	return driver_register(&sbp2_driver.driver);
1648 }
1649 
1650 static void __exit sbp2_cleanup(void)
1651 {
1652 	driver_unregister(&sbp2_driver.driver);
1653 }
1654 
1655 module_init(sbp2_init);
1656 module_exit(sbp2_cleanup);
1657