xref: /openbmc/linux/drivers/firewire/ohci.c (revision 15e47304)
1 /*
2  * Driver for OHCI 1394 controllers
3  *
4  * Copyright (C) 2003-2006 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 #include <linux/bitops.h>
22 #include <linux/bug.h>
23 #include <linux/compiler.h>
24 #include <linux/delay.h>
25 #include <linux/device.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/firewire.h>
28 #include <linux/firewire-constants.h>
29 #include <linux/init.h>
30 #include <linux/interrupt.h>
31 #include <linux/io.h>
32 #include <linux/kernel.h>
33 #include <linux/list.h>
34 #include <linux/mm.h>
35 #include <linux/module.h>
36 #include <linux/moduleparam.h>
37 #include <linux/mutex.h>
38 #include <linux/pci.h>
39 #include <linux/pci_ids.h>
40 #include <linux/slab.h>
41 #include <linux/spinlock.h>
42 #include <linux/string.h>
43 #include <linux/time.h>
44 #include <linux/vmalloc.h>
45 #include <linux/workqueue.h>
46 
47 #include <asm/byteorder.h>
48 #include <asm/page.h>
49 
50 #ifdef CONFIG_PPC_PMAC
51 #include <asm/pmac_feature.h>
52 #endif
53 
54 #include "core.h"
55 #include "ohci.h"
56 
57 #define DESCRIPTOR_OUTPUT_MORE		0
58 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
59 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
60 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
61 #define DESCRIPTOR_STATUS		(1 << 11)
62 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
63 #define DESCRIPTOR_PING			(1 << 7)
64 #define DESCRIPTOR_YY			(1 << 6)
65 #define DESCRIPTOR_NO_IRQ		(0 << 4)
66 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
67 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
68 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
69 #define DESCRIPTOR_WAIT			(3 << 0)
70 
71 struct descriptor {
72 	__le16 req_count;
73 	__le16 control;
74 	__le32 data_address;
75 	__le32 branch_address;
76 	__le16 res_count;
77 	__le16 transfer_status;
78 } __attribute__((aligned(16)));
79 
80 #define CONTROL_SET(regs)	(regs)
81 #define CONTROL_CLEAR(regs)	((regs) + 4)
82 #define COMMAND_PTR(regs)	((regs) + 12)
83 #define CONTEXT_MATCH(regs)	((regs) + 16)
84 
85 #define AR_BUFFER_SIZE	(32*1024)
86 #define AR_BUFFERS_MIN	DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
87 /* we need at least two pages for proper list management */
88 #define AR_BUFFERS	(AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)
89 
90 #define MAX_ASYNC_PAYLOAD	4096
91 #define MAX_AR_PACKET_SIZE	(16 + MAX_ASYNC_PAYLOAD + 4)
92 #define AR_WRAPAROUND_PAGES	DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)
93 
94 struct ar_context {
95 	struct fw_ohci *ohci;
96 	struct page *pages[AR_BUFFERS];
97 	void *buffer;
98 	struct descriptor *descriptors;
99 	dma_addr_t descriptors_bus;
100 	void *pointer;
101 	unsigned int last_buffer_index;
102 	u32 regs;
103 	struct tasklet_struct tasklet;
104 };
105 
106 struct context;
107 
108 typedef int (*descriptor_callback_t)(struct context *ctx,
109 				     struct descriptor *d,
110 				     struct descriptor *last);
111 
112 /*
113  * A buffer that contains a block of DMA-able coherent memory used for
114  * storing a portion of a DMA descriptor program.
115  */
116 struct descriptor_buffer {
117 	struct list_head list;
118 	dma_addr_t buffer_bus;
119 	size_t buffer_size;
120 	size_t used;
121 	struct descriptor buffer[0];
122 };
123 
124 struct context {
125 	struct fw_ohci *ohci;
126 	u32 regs;
127 	int total_allocation;
128 	u32 current_bus;
129 	bool running;
130 	bool flushing;
131 
132 	/*
133 	 * List of page-sized buffers for storing DMA descriptors.
134 	 * Head of list contains buffers in use and tail of list contains
135 	 * free buffers.
136 	 */
137 	struct list_head buffer_list;
138 
139 	/*
140 	 * Pointer to a buffer inside buffer_list that contains the tail
141 	 * end of the current DMA program.
142 	 */
143 	struct descriptor_buffer *buffer_tail;
144 
145 	/*
146 	 * The descriptor containing the branch address of the first
147 	 * descriptor that has not yet been filled by the device.
148 	 */
149 	struct descriptor *last;
150 
151 	/*
152 	 * The last descriptor in the DMA program.  It contains the branch
153 	 * address that must be updated upon appending a new descriptor.
154 	 */
155 	struct descriptor *prev;
156 
157 	descriptor_callback_t callback;
158 
159 	struct tasklet_struct tasklet;
160 };
161 
162 #define IT_HEADER_SY(v)          ((v) <<  0)
163 #define IT_HEADER_TCODE(v)       ((v) <<  4)
164 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
165 #define IT_HEADER_TAG(v)         ((v) << 14)
166 #define IT_HEADER_SPEED(v)       ((v) << 16)
167 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
168 
169 struct iso_context {
170 	struct fw_iso_context base;
171 	struct context context;
172 	void *header;
173 	size_t header_length;
174 	unsigned long flushing_completions;
175 	u32 mc_buffer_bus;
176 	u16 mc_completed;
177 	u16 last_timestamp;
178 	u8 sync;
179 	u8 tags;
180 };
181 
182 #define CONFIG_ROM_SIZE 1024
183 
184 struct fw_ohci {
185 	struct fw_card card;
186 
187 	__iomem char *registers;
188 	int node_id;
189 	int generation;
190 	int request_generation;	/* for timestamping incoming requests */
191 	unsigned quirks;
192 	unsigned int pri_req_max;
193 	u32 bus_time;
194 	bool bus_time_running;
195 	bool is_root;
196 	bool csr_state_setclear_abdicate;
197 	int n_ir;
198 	int n_it;
199 	/*
200 	 * Spinlock for accessing fw_ohci data.  Never call out of
201 	 * this driver with this lock held.
202 	 */
203 	spinlock_t lock;
204 
205 	struct mutex phy_reg_mutex;
206 
207 	void *misc_buffer;
208 	dma_addr_t misc_buffer_bus;
209 
210 	struct ar_context ar_request_ctx;
211 	struct ar_context ar_response_ctx;
212 	struct context at_request_ctx;
213 	struct context at_response_ctx;
214 
215 	u32 it_context_support;
216 	u32 it_context_mask;     /* unoccupied IT contexts */
217 	struct iso_context *it_context_list;
218 	u64 ir_context_channels; /* unoccupied channels */
219 	u32 ir_context_support;
220 	u32 ir_context_mask;     /* unoccupied IR contexts */
221 	struct iso_context *ir_context_list;
222 	u64 mc_channels; /* channels in use by the multichannel IR context */
223 	bool mc_allocated;
224 
225 	__be32    *config_rom;
226 	dma_addr_t config_rom_bus;
227 	__be32    *next_config_rom;
228 	dma_addr_t next_config_rom_bus;
229 	__be32     next_header;
230 
231 	__le32    *self_id_cpu;
232 	dma_addr_t self_id_bus;
233 	struct work_struct bus_reset_work;
234 
235 	u32 self_id_buffer[512];
236 };
237 
238 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
239 {
240 	return container_of(card, struct fw_ohci, card);
241 }
242 
243 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
244 #define IR_CONTEXT_BUFFER_FILL		0x80000000
245 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
246 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
247 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
248 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
249 
250 #define CONTEXT_RUN	0x8000
251 #define CONTEXT_WAKE	0x1000
252 #define CONTEXT_DEAD	0x0800
253 #define CONTEXT_ACTIVE	0x0400
254 
255 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
256 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
257 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
258 
259 #define OHCI1394_REGISTER_SIZE		0x800
260 #define OHCI1394_PCI_HCI_Control	0x40
261 #define SELF_ID_BUF_SIZE		0x800
262 #define OHCI_TCODE_PHY_PACKET		0x0e
263 #define OHCI_VERSION_1_1		0x010010
264 
265 static char ohci_driver_name[] = KBUILD_MODNAME;
266 
267 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
268 #define PCI_DEVICE_ID_CREATIVE_SB1394	0x4001
269 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
270 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
271 #define PCI_DEVICE_ID_TI_TSB12LV26	0x8020
272 #define PCI_DEVICE_ID_TI_TSB82AA2	0x8025
273 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
274 
275 #define QUIRK_CYCLE_TIMER		1
276 #define QUIRK_RESET_PACKET		2
277 #define QUIRK_BE_HEADERS		4
278 #define QUIRK_NO_1394A			8
279 #define QUIRK_NO_MSI			16
280 #define QUIRK_TI_SLLZ059		32
281 
282 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
283 static const struct {
284 	unsigned short vendor, device, revision, flags;
285 } ohci_quirks[] = {
286 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
287 		QUIRK_CYCLE_TIMER},
288 
289 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
290 		QUIRK_BE_HEADERS},
291 
292 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
293 		QUIRK_NO_MSI},
294 
295 	{PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
296 		QUIRK_RESET_PACKET},
297 
298 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
299 		QUIRK_NO_MSI},
300 
301 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
302 		QUIRK_CYCLE_TIMER},
303 
304 	{PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
305 		QUIRK_NO_MSI},
306 
307 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
308 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
309 
310 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
311 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
312 
313 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
314 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
315 
316 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
317 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
318 
319 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
320 		QUIRK_RESET_PACKET},
321 
322 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
323 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
324 };
325 
326 /* This overrides anything that was found in ohci_quirks[]. */
327 static int param_quirks;
328 module_param_named(quirks, param_quirks, int, 0644);
329 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
330 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
331 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
332 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
333 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
334 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
335 	", TI SLLZ059 erratum = "	__stringify(QUIRK_TI_SLLZ059)
336 	")");
337 
338 #define OHCI_PARAM_DEBUG_AT_AR		1
339 #define OHCI_PARAM_DEBUG_SELFIDS	2
340 #define OHCI_PARAM_DEBUG_IRQS		4
341 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
342 
343 static int param_debug;
344 module_param_named(debug, param_debug, int, 0644);
345 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
346 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
347 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
348 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
349 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
350 	", or a combination, or all = -1)");
351 
352 static void log_irqs(struct fw_ohci *ohci, u32 evt)
353 {
354 	if (likely(!(param_debug &
355 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
356 		return;
357 
358 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
359 	    !(evt & OHCI1394_busReset))
360 		return;
361 
362 	dev_notice(ohci->card.device,
363 	    "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
364 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
365 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
366 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
367 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
368 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
369 	    evt & OHCI1394_isochRx		? " IR"			: "",
370 	    evt & OHCI1394_isochTx		? " IT"			: "",
371 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
372 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
373 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
374 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
375 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
376 	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
377 	    evt & OHCI1394_busReset		? " busReset"		: "",
378 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
379 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
380 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
381 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
382 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
383 		    OHCI1394_cycleInconsistent |
384 		    OHCI1394_regAccessFail | OHCI1394_busReset)
385 						? " ?"			: "");
386 }
387 
388 static const char *speed[] = {
389 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
390 };
391 static const char *power[] = {
392 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
393 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
394 };
395 static const char port[] = { '.', '-', 'p', 'c', };
396 
397 static char _p(u32 *s, int shift)
398 {
399 	return port[*s >> shift & 3];
400 }
401 
402 static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
403 {
404 	u32 *s;
405 
406 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
407 		return;
408 
409 	dev_notice(ohci->card.device,
410 		   "%d selfIDs, generation %d, local node ID %04x\n",
411 		   self_id_count, generation, ohci->node_id);
412 
413 	for (s = ohci->self_id_buffer; self_id_count--; ++s)
414 		if ((*s & 1 << 23) == 0)
415 			dev_notice(ohci->card.device,
416 			    "selfID 0: %08x, phy %d [%c%c%c] "
417 			    "%s gc=%d %s %s%s%s\n",
418 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
419 			    speed[*s >> 14 & 3], *s >> 16 & 63,
420 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
421 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
422 		else
423 			dev_notice(ohci->card.device,
424 			    "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
425 			    *s, *s >> 24 & 63,
426 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
427 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
428 }
429 
430 static const char *evts[] = {
431 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
432 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
433 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
434 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
435 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
436 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
437 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
438 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
439 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
440 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
441 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
442 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
443 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
444 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
445 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
446 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
447 	[0x20] = "pending/cancelled",
448 };
449 static const char *tcodes[] = {
450 	[0x0] = "QW req",		[0x1] = "BW req",
451 	[0x2] = "W resp",		[0x3] = "-reserved-",
452 	[0x4] = "QR req",		[0x5] = "BR req",
453 	[0x6] = "QR resp",		[0x7] = "BR resp",
454 	[0x8] = "cycle start",		[0x9] = "Lk req",
455 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
456 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
457 	[0xe] = "link internal",	[0xf] = "-reserved-",
458 };
459 
460 static void log_ar_at_event(struct fw_ohci *ohci,
461 			    char dir, int speed, u32 *header, int evt)
462 {
463 	int tcode = header[0] >> 4 & 0xf;
464 	char specific[12];
465 
466 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
467 		return;
468 
469 	if (unlikely(evt >= ARRAY_SIZE(evts)))
470 			evt = 0x1f;
471 
472 	if (evt == OHCI1394_evt_bus_reset) {
473 		dev_notice(ohci->card.device,
474 			   "A%c evt_bus_reset, generation %d\n",
475 			   dir, (header[2] >> 16) & 0xff);
476 		return;
477 	}
478 
479 	switch (tcode) {
480 	case 0x0: case 0x6: case 0x8:
481 		snprintf(specific, sizeof(specific), " = %08x",
482 			 be32_to_cpu((__force __be32)header[3]));
483 		break;
484 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
485 		snprintf(specific, sizeof(specific), " %x,%x",
486 			 header[3] >> 16, header[3] & 0xffff);
487 		break;
488 	default:
489 		specific[0] = '\0';
490 	}
491 
492 	switch (tcode) {
493 	case 0xa:
494 		dev_notice(ohci->card.device,
495 			   "A%c %s, %s\n",
496 			   dir, evts[evt], tcodes[tcode]);
497 		break;
498 	case 0xe:
499 		dev_notice(ohci->card.device,
500 			   "A%c %s, PHY %08x %08x\n",
501 			   dir, evts[evt], header[1], header[2]);
502 		break;
503 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
504 		dev_notice(ohci->card.device,
505 			   "A%c spd %x tl %02x, "
506 			   "%04x -> %04x, %s, "
507 			   "%s, %04x%08x%s\n",
508 			   dir, speed, header[0] >> 10 & 0x3f,
509 			   header[1] >> 16, header[0] >> 16, evts[evt],
510 			   tcodes[tcode], header[1] & 0xffff, header[2], specific);
511 		break;
512 	default:
513 		dev_notice(ohci->card.device,
514 			   "A%c spd %x tl %02x, "
515 			   "%04x -> %04x, %s, "
516 			   "%s%s\n",
517 			   dir, speed, header[0] >> 10 & 0x3f,
518 			   header[1] >> 16, header[0] >> 16, evts[evt],
519 			   tcodes[tcode], specific);
520 	}
521 }
522 
523 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
524 {
525 	writel(data, ohci->registers + offset);
526 }
527 
528 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
529 {
530 	return readl(ohci->registers + offset);
531 }
532 
533 static inline void flush_writes(const struct fw_ohci *ohci)
534 {
535 	/* Do a dummy read to flush writes. */
536 	reg_read(ohci, OHCI1394_Version);
537 }
538 
539 /*
540  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
541  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
542  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
543  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
544  */
545 static int read_phy_reg(struct fw_ohci *ohci, int addr)
546 {
547 	u32 val;
548 	int i;
549 
550 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
551 	for (i = 0; i < 3 + 100; i++) {
552 		val = reg_read(ohci, OHCI1394_PhyControl);
553 		if (!~val)
554 			return -ENODEV; /* Card was ejected. */
555 
556 		if (val & OHCI1394_PhyControl_ReadDone)
557 			return OHCI1394_PhyControl_ReadData(val);
558 
559 		/*
560 		 * Try a few times without waiting.  Sleeping is necessary
561 		 * only when the link/PHY interface is busy.
562 		 */
563 		if (i >= 3)
564 			msleep(1);
565 	}
566 	dev_err(ohci->card.device, "failed to read phy reg\n");
567 
568 	return -EBUSY;
569 }
570 
571 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
572 {
573 	int i;
574 
575 	reg_write(ohci, OHCI1394_PhyControl,
576 		  OHCI1394_PhyControl_Write(addr, val));
577 	for (i = 0; i < 3 + 100; i++) {
578 		val = reg_read(ohci, OHCI1394_PhyControl);
579 		if (!~val)
580 			return -ENODEV; /* Card was ejected. */
581 
582 		if (!(val & OHCI1394_PhyControl_WritePending))
583 			return 0;
584 
585 		if (i >= 3)
586 			msleep(1);
587 	}
588 	dev_err(ohci->card.device, "failed to write phy reg\n");
589 
590 	return -EBUSY;
591 }
592 
593 static int update_phy_reg(struct fw_ohci *ohci, int addr,
594 			  int clear_bits, int set_bits)
595 {
596 	int ret = read_phy_reg(ohci, addr);
597 	if (ret < 0)
598 		return ret;
599 
600 	/*
601 	 * The interrupt status bits are cleared by writing a one bit.
602 	 * Avoid clearing them unless explicitly requested in set_bits.
603 	 */
604 	if (addr == 5)
605 		clear_bits |= PHY_INT_STATUS_BITS;
606 
607 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
608 }
609 
610 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
611 {
612 	int ret;
613 
614 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
615 	if (ret < 0)
616 		return ret;
617 
618 	return read_phy_reg(ohci, addr);
619 }
620 
621 static int ohci_read_phy_reg(struct fw_card *card, int addr)
622 {
623 	struct fw_ohci *ohci = fw_ohci(card);
624 	int ret;
625 
626 	mutex_lock(&ohci->phy_reg_mutex);
627 	ret = read_phy_reg(ohci, addr);
628 	mutex_unlock(&ohci->phy_reg_mutex);
629 
630 	return ret;
631 }
632 
633 static int ohci_update_phy_reg(struct fw_card *card, int addr,
634 			       int clear_bits, int set_bits)
635 {
636 	struct fw_ohci *ohci = fw_ohci(card);
637 	int ret;
638 
639 	mutex_lock(&ohci->phy_reg_mutex);
640 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
641 	mutex_unlock(&ohci->phy_reg_mutex);
642 
643 	return ret;
644 }
645 
646 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
647 {
648 	return page_private(ctx->pages[i]);
649 }
650 
651 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
652 {
653 	struct descriptor *d;
654 
655 	d = &ctx->descriptors[index];
656 	d->branch_address  &= cpu_to_le32(~0xf);
657 	d->res_count       =  cpu_to_le16(PAGE_SIZE);
658 	d->transfer_status =  0;
659 
660 	wmb(); /* finish init of new descriptors before branch_address update */
661 	d = &ctx->descriptors[ctx->last_buffer_index];
662 	d->branch_address  |= cpu_to_le32(1);
663 
664 	ctx->last_buffer_index = index;
665 
666 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
667 }
668 
669 static void ar_context_release(struct ar_context *ctx)
670 {
671 	unsigned int i;
672 
673 	if (ctx->buffer)
674 		vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
675 
676 	for (i = 0; i < AR_BUFFERS; i++)
677 		if (ctx->pages[i]) {
678 			dma_unmap_page(ctx->ohci->card.device,
679 				       ar_buffer_bus(ctx, i),
680 				       PAGE_SIZE, DMA_FROM_DEVICE);
681 			__free_page(ctx->pages[i]);
682 		}
683 }
684 
685 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
686 {
687 	struct fw_ohci *ohci = ctx->ohci;
688 
689 	if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
690 		reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
691 		flush_writes(ohci);
692 
693 		dev_err(ohci->card.device, "AR error: %s; DMA stopped\n",
694 			error_msg);
695 	}
696 	/* FIXME: restart? */
697 }
698 
699 static inline unsigned int ar_next_buffer_index(unsigned int index)
700 {
701 	return (index + 1) % AR_BUFFERS;
702 }
703 
704 static inline unsigned int ar_prev_buffer_index(unsigned int index)
705 {
706 	return (index - 1 + AR_BUFFERS) % AR_BUFFERS;
707 }
708 
709 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
710 {
711 	return ar_next_buffer_index(ctx->last_buffer_index);
712 }
713 
714 /*
715  * We search for the buffer that contains the last AR packet DMA data written
716  * by the controller.
717  */
718 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
719 						 unsigned int *buffer_offset)
720 {
721 	unsigned int i, next_i, last = ctx->last_buffer_index;
722 	__le16 res_count, next_res_count;
723 
724 	i = ar_first_buffer_index(ctx);
725 	res_count = ACCESS_ONCE(ctx->descriptors[i].res_count);
726 
727 	/* A buffer that is not yet completely filled must be the last one. */
728 	while (i != last && res_count == 0) {
729 
730 		/* Peek at the next descriptor. */
731 		next_i = ar_next_buffer_index(i);
732 		rmb(); /* read descriptors in order */
733 		next_res_count = ACCESS_ONCE(
734 				ctx->descriptors[next_i].res_count);
735 		/*
736 		 * If the next descriptor is still empty, we must stop at this
737 		 * descriptor.
738 		 */
739 		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
740 			/*
741 			 * The exception is when the DMA data for one packet is
742 			 * split over three buffers; in this case, the middle
743 			 * buffer's descriptor might be never updated by the
744 			 * controller and look still empty, and we have to peek
745 			 * at the third one.
746 			 */
747 			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
748 				next_i = ar_next_buffer_index(next_i);
749 				rmb();
750 				next_res_count = ACCESS_ONCE(
751 					ctx->descriptors[next_i].res_count);
752 				if (next_res_count != cpu_to_le16(PAGE_SIZE))
753 					goto next_buffer_is_active;
754 			}
755 
756 			break;
757 		}
758 
759 next_buffer_is_active:
760 		i = next_i;
761 		res_count = next_res_count;
762 	}
763 
764 	rmb(); /* read res_count before the DMA data */
765 
766 	*buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
767 	if (*buffer_offset > PAGE_SIZE) {
768 		*buffer_offset = 0;
769 		ar_context_abort(ctx, "corrupted descriptor");
770 	}
771 
772 	return i;
773 }
774 
775 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
776 				    unsigned int end_buffer_index,
777 				    unsigned int end_buffer_offset)
778 {
779 	unsigned int i;
780 
781 	i = ar_first_buffer_index(ctx);
782 	while (i != end_buffer_index) {
783 		dma_sync_single_for_cpu(ctx->ohci->card.device,
784 					ar_buffer_bus(ctx, i),
785 					PAGE_SIZE, DMA_FROM_DEVICE);
786 		i = ar_next_buffer_index(i);
787 	}
788 	if (end_buffer_offset > 0)
789 		dma_sync_single_for_cpu(ctx->ohci->card.device,
790 					ar_buffer_bus(ctx, i),
791 					end_buffer_offset, DMA_FROM_DEVICE);
792 }
793 
794 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
795 #define cond_le32_to_cpu(v) \
796 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
797 #else
798 #define cond_le32_to_cpu(v) le32_to_cpu(v)
799 #endif
800 
801 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
802 {
803 	struct fw_ohci *ohci = ctx->ohci;
804 	struct fw_packet p;
805 	u32 status, length, tcode;
806 	int evt;
807 
808 	p.header[0] = cond_le32_to_cpu(buffer[0]);
809 	p.header[1] = cond_le32_to_cpu(buffer[1]);
810 	p.header[2] = cond_le32_to_cpu(buffer[2]);
811 
812 	tcode = (p.header[0] >> 4) & 0x0f;
813 	switch (tcode) {
814 	case TCODE_WRITE_QUADLET_REQUEST:
815 	case TCODE_READ_QUADLET_RESPONSE:
816 		p.header[3] = (__force __u32) buffer[3];
817 		p.header_length = 16;
818 		p.payload_length = 0;
819 		break;
820 
821 	case TCODE_READ_BLOCK_REQUEST :
822 		p.header[3] = cond_le32_to_cpu(buffer[3]);
823 		p.header_length = 16;
824 		p.payload_length = 0;
825 		break;
826 
827 	case TCODE_WRITE_BLOCK_REQUEST:
828 	case TCODE_READ_BLOCK_RESPONSE:
829 	case TCODE_LOCK_REQUEST:
830 	case TCODE_LOCK_RESPONSE:
831 		p.header[3] = cond_le32_to_cpu(buffer[3]);
832 		p.header_length = 16;
833 		p.payload_length = p.header[3] >> 16;
834 		if (p.payload_length > MAX_ASYNC_PAYLOAD) {
835 			ar_context_abort(ctx, "invalid packet length");
836 			return NULL;
837 		}
838 		break;
839 
840 	case TCODE_WRITE_RESPONSE:
841 	case TCODE_READ_QUADLET_REQUEST:
842 	case OHCI_TCODE_PHY_PACKET:
843 		p.header_length = 12;
844 		p.payload_length = 0;
845 		break;
846 
847 	default:
848 		ar_context_abort(ctx, "invalid tcode");
849 		return NULL;
850 	}
851 
852 	p.payload = (void *) buffer + p.header_length;
853 
854 	/* FIXME: What to do about evt_* errors? */
855 	length = (p.header_length + p.payload_length + 3) / 4;
856 	status = cond_le32_to_cpu(buffer[length]);
857 	evt    = (status >> 16) & 0x1f;
858 
859 	p.ack        = evt - 16;
860 	p.speed      = (status >> 21) & 0x7;
861 	p.timestamp  = status & 0xffff;
862 	p.generation = ohci->request_generation;
863 
864 	log_ar_at_event(ohci, 'R', p.speed, p.header, evt);
865 
866 	/*
867 	 * Several controllers, notably from NEC and VIA, forget to
868 	 * write ack_complete status at PHY packet reception.
869 	 */
870 	if (evt == OHCI1394_evt_no_status &&
871 	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
872 		p.ack = ACK_COMPLETE;
873 
874 	/*
875 	 * The OHCI bus reset handler synthesizes a PHY packet with
876 	 * the new generation number when a bus reset happens (see
877 	 * section 8.4.2.3).  This helps us determine when a request
878 	 * was received and make sure we send the response in the same
879 	 * generation.  We only need this for requests; for responses
880 	 * we use the unique tlabel for finding the matching
881 	 * request.
882 	 *
883 	 * Alas some chips sometimes emit bus reset packets with a
884 	 * wrong generation.  We set the correct generation for these
885 	 * at a slightly incorrect time (in bus_reset_work).
886 	 */
887 	if (evt == OHCI1394_evt_bus_reset) {
888 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
889 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
890 	} else if (ctx == &ohci->ar_request_ctx) {
891 		fw_core_handle_request(&ohci->card, &p);
892 	} else {
893 		fw_core_handle_response(&ohci->card, &p);
894 	}
895 
896 	return buffer + length + 1;
897 }
898 
899 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
900 {
901 	void *next;
902 
903 	while (p < end) {
904 		next = handle_ar_packet(ctx, p);
905 		if (!next)
906 			return p;
907 		p = next;
908 	}
909 
910 	return p;
911 }
912 
913 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
914 {
915 	unsigned int i;
916 
917 	i = ar_first_buffer_index(ctx);
918 	while (i != end_buffer) {
919 		dma_sync_single_for_device(ctx->ohci->card.device,
920 					   ar_buffer_bus(ctx, i),
921 					   PAGE_SIZE, DMA_FROM_DEVICE);
922 		ar_context_link_page(ctx, i);
923 		i = ar_next_buffer_index(i);
924 	}
925 }
926 
927 static void ar_context_tasklet(unsigned long data)
928 {
929 	struct ar_context *ctx = (struct ar_context *)data;
930 	unsigned int end_buffer_index, end_buffer_offset;
931 	void *p, *end;
932 
933 	p = ctx->pointer;
934 	if (!p)
935 		return;
936 
937 	end_buffer_index = ar_search_last_active_buffer(ctx,
938 							&end_buffer_offset);
939 	ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
940 	end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
941 
942 	if (end_buffer_index < ar_first_buffer_index(ctx)) {
943 		/*
944 		 * The filled part of the overall buffer wraps around; handle
945 		 * all packets up to the buffer end here.  If the last packet
946 		 * wraps around, its tail will be visible after the buffer end
947 		 * because the buffer start pages are mapped there again.
948 		 */
949 		void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
950 		p = handle_ar_packets(ctx, p, buffer_end);
951 		if (p < buffer_end)
952 			goto error;
953 		/* adjust p to point back into the actual buffer */
954 		p -= AR_BUFFERS * PAGE_SIZE;
955 	}
956 
957 	p = handle_ar_packets(ctx, p, end);
958 	if (p != end) {
959 		if (p > end)
960 			ar_context_abort(ctx, "inconsistent descriptor");
961 		goto error;
962 	}
963 
964 	ctx->pointer = p;
965 	ar_recycle_buffers(ctx, end_buffer_index);
966 
967 	return;
968 
969 error:
970 	ctx->pointer = NULL;
971 }
972 
973 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
974 			   unsigned int descriptors_offset, u32 regs)
975 {
976 	unsigned int i;
977 	dma_addr_t dma_addr;
978 	struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
979 	struct descriptor *d;
980 
981 	ctx->regs        = regs;
982 	ctx->ohci        = ohci;
983 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
984 
985 	for (i = 0; i < AR_BUFFERS; i++) {
986 		ctx->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32);
987 		if (!ctx->pages[i])
988 			goto out_of_memory;
989 		dma_addr = dma_map_page(ohci->card.device, ctx->pages[i],
990 					0, PAGE_SIZE, DMA_FROM_DEVICE);
991 		if (dma_mapping_error(ohci->card.device, dma_addr)) {
992 			__free_page(ctx->pages[i]);
993 			ctx->pages[i] = NULL;
994 			goto out_of_memory;
995 		}
996 		set_page_private(ctx->pages[i], dma_addr);
997 	}
998 
999 	for (i = 0; i < AR_BUFFERS; i++)
1000 		pages[i]              = ctx->pages[i];
1001 	for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
1002 		pages[AR_BUFFERS + i] = ctx->pages[i];
1003 	ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
1004 				 -1, PAGE_KERNEL);
1005 	if (!ctx->buffer)
1006 		goto out_of_memory;
1007 
1008 	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
1009 	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
1010 
1011 	for (i = 0; i < AR_BUFFERS; i++) {
1012 		d = &ctx->descriptors[i];
1013 		d->req_count      = cpu_to_le16(PAGE_SIZE);
1014 		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
1015 						DESCRIPTOR_STATUS |
1016 						DESCRIPTOR_BRANCH_ALWAYS);
1017 		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
1018 		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
1019 			ar_next_buffer_index(i) * sizeof(struct descriptor));
1020 	}
1021 
1022 	return 0;
1023 
1024 out_of_memory:
1025 	ar_context_release(ctx);
1026 
1027 	return -ENOMEM;
1028 }
1029 
1030 static void ar_context_run(struct ar_context *ctx)
1031 {
1032 	unsigned int i;
1033 
1034 	for (i = 0; i < AR_BUFFERS; i++)
1035 		ar_context_link_page(ctx, i);
1036 
1037 	ctx->pointer = ctx->buffer;
1038 
1039 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1040 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1041 }
1042 
1043 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1044 {
1045 	__le16 branch;
1046 
1047 	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1048 
1049 	/* figure out which descriptor the branch address goes in */
1050 	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1051 		return d;
1052 	else
1053 		return d + z - 1;
1054 }
1055 
1056 static void context_tasklet(unsigned long data)
1057 {
1058 	struct context *ctx = (struct context *) data;
1059 	struct descriptor *d, *last;
1060 	u32 address;
1061 	int z;
1062 	struct descriptor_buffer *desc;
1063 
1064 	desc = list_entry(ctx->buffer_list.next,
1065 			struct descriptor_buffer, list);
1066 	last = ctx->last;
1067 	while (last->branch_address != 0) {
1068 		struct descriptor_buffer *old_desc = desc;
1069 		address = le32_to_cpu(last->branch_address);
1070 		z = address & 0xf;
1071 		address &= ~0xf;
1072 		ctx->current_bus = address;
1073 
1074 		/* If the branch address points to a buffer outside of the
1075 		 * current buffer, advance to the next buffer. */
1076 		if (address < desc->buffer_bus ||
1077 				address >= desc->buffer_bus + desc->used)
1078 			desc = list_entry(desc->list.next,
1079 					struct descriptor_buffer, list);
1080 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1081 		last = find_branch_descriptor(d, z);
1082 
1083 		if (!ctx->callback(ctx, d, last))
1084 			break;
1085 
1086 		if (old_desc != desc) {
1087 			/* If we've advanced to the next buffer, move the
1088 			 * previous buffer to the free list. */
1089 			unsigned long flags;
1090 			old_desc->used = 0;
1091 			spin_lock_irqsave(&ctx->ohci->lock, flags);
1092 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1093 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1094 		}
1095 		ctx->last = last;
1096 	}
1097 }
1098 
1099 /*
1100  * Allocate a new buffer and add it to the list of free buffers for this
1101  * context.  Must be called with ohci->lock held.
1102  */
1103 static int context_add_buffer(struct context *ctx)
1104 {
1105 	struct descriptor_buffer *desc;
1106 	dma_addr_t uninitialized_var(bus_addr);
1107 	int offset;
1108 
1109 	/*
1110 	 * 16MB of descriptors should be far more than enough for any DMA
1111 	 * program.  This will catch run-away userspace or DoS attacks.
1112 	 */
1113 	if (ctx->total_allocation >= 16*1024*1024)
1114 		return -ENOMEM;
1115 
1116 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1117 			&bus_addr, GFP_ATOMIC);
1118 	if (!desc)
1119 		return -ENOMEM;
1120 
1121 	offset = (void *)&desc->buffer - (void *)desc;
1122 	desc->buffer_size = PAGE_SIZE - offset;
1123 	desc->buffer_bus = bus_addr + offset;
1124 	desc->used = 0;
1125 
1126 	list_add_tail(&desc->list, &ctx->buffer_list);
1127 	ctx->total_allocation += PAGE_SIZE;
1128 
1129 	return 0;
1130 }
1131 
1132 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1133 			u32 regs, descriptor_callback_t callback)
1134 {
1135 	ctx->ohci = ohci;
1136 	ctx->regs = regs;
1137 	ctx->total_allocation = 0;
1138 
1139 	INIT_LIST_HEAD(&ctx->buffer_list);
1140 	if (context_add_buffer(ctx) < 0)
1141 		return -ENOMEM;
1142 
1143 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1144 			struct descriptor_buffer, list);
1145 
1146 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1147 	ctx->callback = callback;
1148 
1149 	/*
1150 	 * We put a dummy descriptor in the buffer that has a NULL
1151 	 * branch address and looks like it's been sent.  That way we
1152 	 * have a descriptor to append DMA programs to.
1153 	 */
1154 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1155 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1156 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1157 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1158 	ctx->last = ctx->buffer_tail->buffer;
1159 	ctx->prev = ctx->buffer_tail->buffer;
1160 
1161 	return 0;
1162 }
1163 
1164 static void context_release(struct context *ctx)
1165 {
1166 	struct fw_card *card = &ctx->ohci->card;
1167 	struct descriptor_buffer *desc, *tmp;
1168 
1169 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1170 		dma_free_coherent(card->device, PAGE_SIZE, desc,
1171 			desc->buffer_bus -
1172 			((void *)&desc->buffer - (void *)desc));
1173 }
1174 
1175 /* Must be called with ohci->lock held */
1176 static struct descriptor *context_get_descriptors(struct context *ctx,
1177 						  int z, dma_addr_t *d_bus)
1178 {
1179 	struct descriptor *d = NULL;
1180 	struct descriptor_buffer *desc = ctx->buffer_tail;
1181 
1182 	if (z * sizeof(*d) > desc->buffer_size)
1183 		return NULL;
1184 
1185 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1186 		/* No room for the descriptor in this buffer, so advance to the
1187 		 * next one. */
1188 
1189 		if (desc->list.next == &ctx->buffer_list) {
1190 			/* If there is no free buffer next in the list,
1191 			 * allocate one. */
1192 			if (context_add_buffer(ctx) < 0)
1193 				return NULL;
1194 		}
1195 		desc = list_entry(desc->list.next,
1196 				struct descriptor_buffer, list);
1197 		ctx->buffer_tail = desc;
1198 	}
1199 
1200 	d = desc->buffer + desc->used / sizeof(*d);
1201 	memset(d, 0, z * sizeof(*d));
1202 	*d_bus = desc->buffer_bus + desc->used;
1203 
1204 	return d;
1205 }
1206 
1207 static void context_run(struct context *ctx, u32 extra)
1208 {
1209 	struct fw_ohci *ohci = ctx->ohci;
1210 
1211 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1212 		  le32_to_cpu(ctx->last->branch_address));
1213 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1214 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1215 	ctx->running = true;
1216 	flush_writes(ohci);
1217 }
1218 
1219 static void context_append(struct context *ctx,
1220 			   struct descriptor *d, int z, int extra)
1221 {
1222 	dma_addr_t d_bus;
1223 	struct descriptor_buffer *desc = ctx->buffer_tail;
1224 
1225 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1226 
1227 	desc->used += (z + extra) * sizeof(*d);
1228 
1229 	wmb(); /* finish init of new descriptors before branch_address update */
1230 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1231 	ctx->prev = find_branch_descriptor(d, z);
1232 }
1233 
1234 static void context_stop(struct context *ctx)
1235 {
1236 	struct fw_ohci *ohci = ctx->ohci;
1237 	u32 reg;
1238 	int i;
1239 
1240 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1241 	ctx->running = false;
1242 
1243 	for (i = 0; i < 1000; i++) {
1244 		reg = reg_read(ohci, CONTROL_SET(ctx->regs));
1245 		if ((reg & CONTEXT_ACTIVE) == 0)
1246 			return;
1247 
1248 		if (i)
1249 			udelay(10);
1250 	}
1251 	dev_err(ohci->card.device, "DMA context still active (0x%08x)\n", reg);
1252 }
1253 
1254 struct driver_data {
1255 	u8 inline_data[8];
1256 	struct fw_packet *packet;
1257 };
1258 
1259 /*
1260  * This function apppends a packet to the DMA queue for transmission.
1261  * Must always be called with the ochi->lock held to ensure proper
1262  * generation handling and locking around packet queue manipulation.
1263  */
1264 static int at_context_queue_packet(struct context *ctx,
1265 				   struct fw_packet *packet)
1266 {
1267 	struct fw_ohci *ohci = ctx->ohci;
1268 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1269 	struct driver_data *driver_data;
1270 	struct descriptor *d, *last;
1271 	__le32 *header;
1272 	int z, tcode;
1273 
1274 	d = context_get_descriptors(ctx, 4, &d_bus);
1275 	if (d == NULL) {
1276 		packet->ack = RCODE_SEND_ERROR;
1277 		return -1;
1278 	}
1279 
1280 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1281 	d[0].res_count = cpu_to_le16(packet->timestamp);
1282 
1283 	/*
1284 	 * The DMA format for asyncronous link packets is different
1285 	 * from the IEEE1394 layout, so shift the fields around
1286 	 * accordingly.
1287 	 */
1288 
1289 	tcode = (packet->header[0] >> 4) & 0x0f;
1290 	header = (__le32 *) &d[1];
1291 	switch (tcode) {
1292 	case TCODE_WRITE_QUADLET_REQUEST:
1293 	case TCODE_WRITE_BLOCK_REQUEST:
1294 	case TCODE_WRITE_RESPONSE:
1295 	case TCODE_READ_QUADLET_REQUEST:
1296 	case TCODE_READ_BLOCK_REQUEST:
1297 	case TCODE_READ_QUADLET_RESPONSE:
1298 	case TCODE_READ_BLOCK_RESPONSE:
1299 	case TCODE_LOCK_REQUEST:
1300 	case TCODE_LOCK_RESPONSE:
1301 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1302 					(packet->speed << 16));
1303 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1304 					(packet->header[0] & 0xffff0000));
1305 		header[2] = cpu_to_le32(packet->header[2]);
1306 
1307 		if (TCODE_IS_BLOCK_PACKET(tcode))
1308 			header[3] = cpu_to_le32(packet->header[3]);
1309 		else
1310 			header[3] = (__force __le32) packet->header[3];
1311 
1312 		d[0].req_count = cpu_to_le16(packet->header_length);
1313 		break;
1314 
1315 	case TCODE_LINK_INTERNAL:
1316 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1317 					(packet->speed << 16));
1318 		header[1] = cpu_to_le32(packet->header[1]);
1319 		header[2] = cpu_to_le32(packet->header[2]);
1320 		d[0].req_count = cpu_to_le16(12);
1321 
1322 		if (is_ping_packet(&packet->header[1]))
1323 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1324 		break;
1325 
1326 	case TCODE_STREAM_DATA:
1327 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1328 					(packet->speed << 16));
1329 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1330 		d[0].req_count = cpu_to_le16(8);
1331 		break;
1332 
1333 	default:
1334 		/* BUG(); */
1335 		packet->ack = RCODE_SEND_ERROR;
1336 		return -1;
1337 	}
1338 
1339 	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1340 	driver_data = (struct driver_data *) &d[3];
1341 	driver_data->packet = packet;
1342 	packet->driver_data = driver_data;
1343 
1344 	if (packet->payload_length > 0) {
1345 		if (packet->payload_length > sizeof(driver_data->inline_data)) {
1346 			payload_bus = dma_map_single(ohci->card.device,
1347 						     packet->payload,
1348 						     packet->payload_length,
1349 						     DMA_TO_DEVICE);
1350 			if (dma_mapping_error(ohci->card.device, payload_bus)) {
1351 				packet->ack = RCODE_SEND_ERROR;
1352 				return -1;
1353 			}
1354 			packet->payload_bus	= payload_bus;
1355 			packet->payload_mapped	= true;
1356 		} else {
1357 			memcpy(driver_data->inline_data, packet->payload,
1358 			       packet->payload_length);
1359 			payload_bus = d_bus + 3 * sizeof(*d);
1360 		}
1361 
1362 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1363 		d[2].data_address = cpu_to_le32(payload_bus);
1364 		last = &d[2];
1365 		z = 3;
1366 	} else {
1367 		last = &d[0];
1368 		z = 2;
1369 	}
1370 
1371 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1372 				     DESCRIPTOR_IRQ_ALWAYS |
1373 				     DESCRIPTOR_BRANCH_ALWAYS);
1374 
1375 	/* FIXME: Document how the locking works. */
1376 	if (ohci->generation != packet->generation) {
1377 		if (packet->payload_mapped)
1378 			dma_unmap_single(ohci->card.device, payload_bus,
1379 					 packet->payload_length, DMA_TO_DEVICE);
1380 		packet->ack = RCODE_GENERATION;
1381 		return -1;
1382 	}
1383 
1384 	context_append(ctx, d, z, 4 - z);
1385 
1386 	if (ctx->running)
1387 		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1388 	else
1389 		context_run(ctx, 0);
1390 
1391 	return 0;
1392 }
1393 
1394 static void at_context_flush(struct context *ctx)
1395 {
1396 	tasklet_disable(&ctx->tasklet);
1397 
1398 	ctx->flushing = true;
1399 	context_tasklet((unsigned long)ctx);
1400 	ctx->flushing = false;
1401 
1402 	tasklet_enable(&ctx->tasklet);
1403 }
1404 
1405 static int handle_at_packet(struct context *context,
1406 			    struct descriptor *d,
1407 			    struct descriptor *last)
1408 {
1409 	struct driver_data *driver_data;
1410 	struct fw_packet *packet;
1411 	struct fw_ohci *ohci = context->ohci;
1412 	int evt;
1413 
1414 	if (last->transfer_status == 0 && !context->flushing)
1415 		/* This descriptor isn't done yet, stop iteration. */
1416 		return 0;
1417 
1418 	driver_data = (struct driver_data *) &d[3];
1419 	packet = driver_data->packet;
1420 	if (packet == NULL)
1421 		/* This packet was cancelled, just continue. */
1422 		return 1;
1423 
1424 	if (packet->payload_mapped)
1425 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1426 				 packet->payload_length, DMA_TO_DEVICE);
1427 
1428 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1429 	packet->timestamp = le16_to_cpu(last->res_count);
1430 
1431 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);
1432 
1433 	switch (evt) {
1434 	case OHCI1394_evt_timeout:
1435 		/* Async response transmit timed out. */
1436 		packet->ack = RCODE_CANCELLED;
1437 		break;
1438 
1439 	case OHCI1394_evt_flushed:
1440 		/*
1441 		 * The packet was flushed should give same error as
1442 		 * when we try to use a stale generation count.
1443 		 */
1444 		packet->ack = RCODE_GENERATION;
1445 		break;
1446 
1447 	case OHCI1394_evt_missing_ack:
1448 		if (context->flushing)
1449 			packet->ack = RCODE_GENERATION;
1450 		else {
1451 			/*
1452 			 * Using a valid (current) generation count, but the
1453 			 * node is not on the bus or not sending acks.
1454 			 */
1455 			packet->ack = RCODE_NO_ACK;
1456 		}
1457 		break;
1458 
1459 	case ACK_COMPLETE + 0x10:
1460 	case ACK_PENDING + 0x10:
1461 	case ACK_BUSY_X + 0x10:
1462 	case ACK_BUSY_A + 0x10:
1463 	case ACK_BUSY_B + 0x10:
1464 	case ACK_DATA_ERROR + 0x10:
1465 	case ACK_TYPE_ERROR + 0x10:
1466 		packet->ack = evt - 0x10;
1467 		break;
1468 
1469 	case OHCI1394_evt_no_status:
1470 		if (context->flushing) {
1471 			packet->ack = RCODE_GENERATION;
1472 			break;
1473 		}
1474 		/* fall through */
1475 
1476 	default:
1477 		packet->ack = RCODE_SEND_ERROR;
1478 		break;
1479 	}
1480 
1481 	packet->callback(packet, &ohci->card, packet->ack);
1482 
1483 	return 1;
1484 }
1485 
1486 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1487 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1488 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1489 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1490 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1491 
1492 static void handle_local_rom(struct fw_ohci *ohci,
1493 			     struct fw_packet *packet, u32 csr)
1494 {
1495 	struct fw_packet response;
1496 	int tcode, length, i;
1497 
1498 	tcode = HEADER_GET_TCODE(packet->header[0]);
1499 	if (TCODE_IS_BLOCK_PACKET(tcode))
1500 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1501 	else
1502 		length = 4;
1503 
1504 	i = csr - CSR_CONFIG_ROM;
1505 	if (i + length > CONFIG_ROM_SIZE) {
1506 		fw_fill_response(&response, packet->header,
1507 				 RCODE_ADDRESS_ERROR, NULL, 0);
1508 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1509 		fw_fill_response(&response, packet->header,
1510 				 RCODE_TYPE_ERROR, NULL, 0);
1511 	} else {
1512 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1513 				 (void *) ohci->config_rom + i, length);
1514 	}
1515 
1516 	fw_core_handle_response(&ohci->card, &response);
1517 }
1518 
1519 static void handle_local_lock(struct fw_ohci *ohci,
1520 			      struct fw_packet *packet, u32 csr)
1521 {
1522 	struct fw_packet response;
1523 	int tcode, length, ext_tcode, sel, try;
1524 	__be32 *payload, lock_old;
1525 	u32 lock_arg, lock_data;
1526 
1527 	tcode = HEADER_GET_TCODE(packet->header[0]);
1528 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1529 	payload = packet->payload;
1530 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1531 
1532 	if (tcode == TCODE_LOCK_REQUEST &&
1533 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1534 		lock_arg = be32_to_cpu(payload[0]);
1535 		lock_data = be32_to_cpu(payload[1]);
1536 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1537 		lock_arg = 0;
1538 		lock_data = 0;
1539 	} else {
1540 		fw_fill_response(&response, packet->header,
1541 				 RCODE_TYPE_ERROR, NULL, 0);
1542 		goto out;
1543 	}
1544 
1545 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1546 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1547 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1548 	reg_write(ohci, OHCI1394_CSRControl, sel);
1549 
1550 	for (try = 0; try < 20; try++)
1551 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1552 			lock_old = cpu_to_be32(reg_read(ohci,
1553 							OHCI1394_CSRData));
1554 			fw_fill_response(&response, packet->header,
1555 					 RCODE_COMPLETE,
1556 					 &lock_old, sizeof(lock_old));
1557 			goto out;
1558 		}
1559 
1560 	dev_err(ohci->card.device, "swap not done (CSR lock timeout)\n");
1561 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1562 
1563  out:
1564 	fw_core_handle_response(&ohci->card, &response);
1565 }
1566 
1567 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1568 {
1569 	u64 offset, csr;
1570 
1571 	if (ctx == &ctx->ohci->at_request_ctx) {
1572 		packet->ack = ACK_PENDING;
1573 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1574 	}
1575 
1576 	offset =
1577 		((unsigned long long)
1578 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1579 		packet->header[2];
1580 	csr = offset - CSR_REGISTER_BASE;
1581 
1582 	/* Handle config rom reads. */
1583 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1584 		handle_local_rom(ctx->ohci, packet, csr);
1585 	else switch (csr) {
1586 	case CSR_BUS_MANAGER_ID:
1587 	case CSR_BANDWIDTH_AVAILABLE:
1588 	case CSR_CHANNELS_AVAILABLE_HI:
1589 	case CSR_CHANNELS_AVAILABLE_LO:
1590 		handle_local_lock(ctx->ohci, packet, csr);
1591 		break;
1592 	default:
1593 		if (ctx == &ctx->ohci->at_request_ctx)
1594 			fw_core_handle_request(&ctx->ohci->card, packet);
1595 		else
1596 			fw_core_handle_response(&ctx->ohci->card, packet);
1597 		break;
1598 	}
1599 
1600 	if (ctx == &ctx->ohci->at_response_ctx) {
1601 		packet->ack = ACK_COMPLETE;
1602 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1603 	}
1604 }
1605 
1606 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1607 {
1608 	unsigned long flags;
1609 	int ret;
1610 
1611 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1612 
1613 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1614 	    ctx->ohci->generation == packet->generation) {
1615 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1616 		handle_local_request(ctx, packet);
1617 		return;
1618 	}
1619 
1620 	ret = at_context_queue_packet(ctx, packet);
1621 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1622 
1623 	if (ret < 0)
1624 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1625 
1626 }
1627 
1628 static void detect_dead_context(struct fw_ohci *ohci,
1629 				const char *name, unsigned int regs)
1630 {
1631 	u32 ctl;
1632 
1633 	ctl = reg_read(ohci, CONTROL_SET(regs));
1634 	if (ctl & CONTEXT_DEAD)
1635 		dev_err(ohci->card.device,
1636 			"DMA context %s has stopped, error code: %s\n",
1637 			name, evts[ctl & 0x1f]);
1638 }
1639 
1640 static void handle_dead_contexts(struct fw_ohci *ohci)
1641 {
1642 	unsigned int i;
1643 	char name[8];
1644 
1645 	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1646 	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1647 	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1648 	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1649 	for (i = 0; i < 32; ++i) {
1650 		if (!(ohci->it_context_support & (1 << i)))
1651 			continue;
1652 		sprintf(name, "IT%u", i);
1653 		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1654 	}
1655 	for (i = 0; i < 32; ++i) {
1656 		if (!(ohci->ir_context_support & (1 << i)))
1657 			continue;
1658 		sprintf(name, "IR%u", i);
1659 		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1660 	}
1661 	/* TODO: maybe try to flush and restart the dead contexts */
1662 }
1663 
1664 static u32 cycle_timer_ticks(u32 cycle_timer)
1665 {
1666 	u32 ticks;
1667 
1668 	ticks = cycle_timer & 0xfff;
1669 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1670 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1671 
1672 	return ticks;
1673 }
1674 
1675 /*
1676  * Some controllers exhibit one or more of the following bugs when updating the
1677  * iso cycle timer register:
1678  *  - When the lowest six bits are wrapping around to zero, a read that happens
1679  *    at the same time will return garbage in the lowest ten bits.
1680  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1681  *    not incremented for about 60 ns.
1682  *  - Occasionally, the entire register reads zero.
1683  *
1684  * To catch these, we read the register three times and ensure that the
1685  * difference between each two consecutive reads is approximately the same, i.e.
1686  * less than twice the other.  Furthermore, any negative difference indicates an
1687  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1688  * execute, so we have enough precision to compute the ratio of the differences.)
1689  */
1690 static u32 get_cycle_time(struct fw_ohci *ohci)
1691 {
1692 	u32 c0, c1, c2;
1693 	u32 t0, t1, t2;
1694 	s32 diff01, diff12;
1695 	int i;
1696 
1697 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1698 
1699 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1700 		i = 0;
1701 		c1 = c2;
1702 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1703 		do {
1704 			c0 = c1;
1705 			c1 = c2;
1706 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1707 			t0 = cycle_timer_ticks(c0);
1708 			t1 = cycle_timer_ticks(c1);
1709 			t2 = cycle_timer_ticks(c2);
1710 			diff01 = t1 - t0;
1711 			diff12 = t2 - t1;
1712 		} while ((diff01 <= 0 || diff12 <= 0 ||
1713 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1714 			 && i++ < 20);
1715 	}
1716 
1717 	return c2;
1718 }
1719 
1720 /*
1721  * This function has to be called at least every 64 seconds.  The bus_time
1722  * field stores not only the upper 25 bits of the BUS_TIME register but also
1723  * the most significant bit of the cycle timer in bit 6 so that we can detect
1724  * changes in this bit.
1725  */
1726 static u32 update_bus_time(struct fw_ohci *ohci)
1727 {
1728 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1729 
1730 	if (unlikely(!ohci->bus_time_running)) {
1731 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_cycle64Seconds);
1732 		ohci->bus_time = (lower_32_bits(get_seconds()) & ~0x7f) |
1733 		                 (cycle_time_seconds & 0x40);
1734 		ohci->bus_time_running = true;
1735 	}
1736 
1737 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1738 		ohci->bus_time += 0x40;
1739 
1740 	return ohci->bus_time | cycle_time_seconds;
1741 }
1742 
1743 static int get_status_for_port(struct fw_ohci *ohci, int port_index)
1744 {
1745 	int reg;
1746 
1747 	mutex_lock(&ohci->phy_reg_mutex);
1748 	reg = write_phy_reg(ohci, 7, port_index);
1749 	if (reg >= 0)
1750 		reg = read_phy_reg(ohci, 8);
1751 	mutex_unlock(&ohci->phy_reg_mutex);
1752 	if (reg < 0)
1753 		return reg;
1754 
1755 	switch (reg & 0x0f) {
1756 	case 0x06:
1757 		return 2;	/* is child node (connected to parent node) */
1758 	case 0x0e:
1759 		return 3;	/* is parent node (connected to child node) */
1760 	}
1761 	return 1;		/* not connected */
1762 }
1763 
1764 static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
1765 	int self_id_count)
1766 {
1767 	int i;
1768 	u32 entry;
1769 
1770 	for (i = 0; i < self_id_count; i++) {
1771 		entry = ohci->self_id_buffer[i];
1772 		if ((self_id & 0xff000000) == (entry & 0xff000000))
1773 			return -1;
1774 		if ((self_id & 0xff000000) < (entry & 0xff000000))
1775 			return i;
1776 	}
1777 	return i;
1778 }
1779 
1780 /*
1781  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1782  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1783  * Construct the selfID from phy register contents.
1784  * FIXME:  How to determine the selfID.i flag?
1785  */
1786 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
1787 {
1788 	int reg, i, pos, status;
1789 	/* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
1790 	u32 self_id = 0x8040c800;
1791 
1792 	reg = reg_read(ohci, OHCI1394_NodeID);
1793 	if (!(reg & OHCI1394_NodeID_idValid)) {
1794 		dev_notice(ohci->card.device,
1795 			   "node ID not valid, new bus reset in progress\n");
1796 		return -EBUSY;
1797 	}
1798 	self_id |= ((reg & 0x3f) << 24); /* phy ID */
1799 
1800 	reg = ohci_read_phy_reg(&ohci->card, 4);
1801 	if (reg < 0)
1802 		return reg;
1803 	self_id |= ((reg & 0x07) << 8); /* power class */
1804 
1805 	reg = ohci_read_phy_reg(&ohci->card, 1);
1806 	if (reg < 0)
1807 		return reg;
1808 	self_id |= ((reg & 0x3f) << 16); /* gap count */
1809 
1810 	for (i = 0; i < 3; i++) {
1811 		status = get_status_for_port(ohci, i);
1812 		if (status < 0)
1813 			return status;
1814 		self_id |= ((status & 0x3) << (6 - (i * 2)));
1815 	}
1816 
1817 	pos = get_self_id_pos(ohci, self_id, self_id_count);
1818 	if (pos >= 0) {
1819 		memmove(&(ohci->self_id_buffer[pos+1]),
1820 			&(ohci->self_id_buffer[pos]),
1821 			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
1822 		ohci->self_id_buffer[pos] = self_id;
1823 		self_id_count++;
1824 	}
1825 	return self_id_count;
1826 }
1827 
1828 static void bus_reset_work(struct work_struct *work)
1829 {
1830 	struct fw_ohci *ohci =
1831 		container_of(work, struct fw_ohci, bus_reset_work);
1832 	int self_id_count, generation, new_generation, i, j;
1833 	u32 reg;
1834 	void *free_rom = NULL;
1835 	dma_addr_t free_rom_bus = 0;
1836 	bool is_new_root;
1837 
1838 	reg = reg_read(ohci, OHCI1394_NodeID);
1839 	if (!(reg & OHCI1394_NodeID_idValid)) {
1840 		dev_notice(ohci->card.device,
1841 			   "node ID not valid, new bus reset in progress\n");
1842 		return;
1843 	}
1844 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1845 		dev_notice(ohci->card.device, "malconfigured bus\n");
1846 		return;
1847 	}
1848 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1849 			       OHCI1394_NodeID_nodeNumber);
1850 
1851 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1852 	if (!(ohci->is_root && is_new_root))
1853 		reg_write(ohci, OHCI1394_LinkControlSet,
1854 			  OHCI1394_LinkControl_cycleMaster);
1855 	ohci->is_root = is_new_root;
1856 
1857 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1858 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1859 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1860 		return;
1861 	}
1862 	/*
1863 	 * The count in the SelfIDCount register is the number of
1864 	 * bytes in the self ID receive buffer.  Since we also receive
1865 	 * the inverted quadlets and a header quadlet, we shift one
1866 	 * bit extra to get the actual number of self IDs.
1867 	 */
1868 	self_id_count = (reg >> 3) & 0xff;
1869 
1870 	if (self_id_count > 252) {
1871 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1872 		return;
1873 	}
1874 
1875 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1876 	rmb();
1877 
1878 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1879 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1880 			/*
1881 			 * If the invalid data looks like a cycle start packet,
1882 			 * it's likely to be the result of the cycle master
1883 			 * having a wrong gap count.  In this case, the self IDs
1884 			 * so far are valid and should be processed so that the
1885 			 * bus manager can then correct the gap count.
1886 			 */
1887 			if (cond_le32_to_cpu(ohci->self_id_cpu[i])
1888 							== 0xffff008f) {
1889 				dev_notice(ohci->card.device,
1890 					   "ignoring spurious self IDs\n");
1891 				self_id_count = j;
1892 				break;
1893 			} else {
1894 				dev_notice(ohci->card.device,
1895 					   "inconsistent self IDs\n");
1896 				return;
1897 			}
1898 		}
1899 		ohci->self_id_buffer[j] =
1900 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1901 	}
1902 
1903 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
1904 		self_id_count = find_and_insert_self_id(ohci, self_id_count);
1905 		if (self_id_count < 0) {
1906 			dev_notice(ohci->card.device,
1907 				   "could not construct local self ID\n");
1908 			return;
1909 		}
1910 	}
1911 
1912 	if (self_id_count == 0) {
1913 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1914 		return;
1915 	}
1916 	rmb();
1917 
1918 	/*
1919 	 * Check the consistency of the self IDs we just read.  The
1920 	 * problem we face is that a new bus reset can start while we
1921 	 * read out the self IDs from the DMA buffer. If this happens,
1922 	 * the DMA buffer will be overwritten with new self IDs and we
1923 	 * will read out inconsistent data.  The OHCI specification
1924 	 * (section 11.2) recommends a technique similar to
1925 	 * linux/seqlock.h, where we remember the generation of the
1926 	 * self IDs in the buffer before reading them out and compare
1927 	 * it to the current generation after reading them out.  If
1928 	 * the two generations match we know we have a consistent set
1929 	 * of self IDs.
1930 	 */
1931 
1932 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1933 	if (new_generation != generation) {
1934 		dev_notice(ohci->card.device,
1935 			   "new bus reset, discarding self ids\n");
1936 		return;
1937 	}
1938 
1939 	/* FIXME: Document how the locking works. */
1940 	spin_lock_irq(&ohci->lock);
1941 
1942 	ohci->generation = -1; /* prevent AT packet queueing */
1943 	context_stop(&ohci->at_request_ctx);
1944 	context_stop(&ohci->at_response_ctx);
1945 
1946 	spin_unlock_irq(&ohci->lock);
1947 
1948 	/*
1949 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
1950 	 * packets in the AT queues and software needs to drain them.
1951 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
1952 	 */
1953 	at_context_flush(&ohci->at_request_ctx);
1954 	at_context_flush(&ohci->at_response_ctx);
1955 
1956 	spin_lock_irq(&ohci->lock);
1957 
1958 	ohci->generation = generation;
1959 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1960 
1961 	if (ohci->quirks & QUIRK_RESET_PACKET)
1962 		ohci->request_generation = generation;
1963 
1964 	/*
1965 	 * This next bit is unrelated to the AT context stuff but we
1966 	 * have to do it under the spinlock also.  If a new config rom
1967 	 * was set up before this reset, the old one is now no longer
1968 	 * in use and we can free it. Update the config rom pointers
1969 	 * to point to the current config rom and clear the
1970 	 * next_config_rom pointer so a new update can take place.
1971 	 */
1972 
1973 	if (ohci->next_config_rom != NULL) {
1974 		if (ohci->next_config_rom != ohci->config_rom) {
1975 			free_rom      = ohci->config_rom;
1976 			free_rom_bus  = ohci->config_rom_bus;
1977 		}
1978 		ohci->config_rom      = ohci->next_config_rom;
1979 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1980 		ohci->next_config_rom = NULL;
1981 
1982 		/*
1983 		 * Restore config_rom image and manually update
1984 		 * config_rom registers.  Writing the header quadlet
1985 		 * will indicate that the config rom is ready, so we
1986 		 * do that last.
1987 		 */
1988 		reg_write(ohci, OHCI1394_BusOptions,
1989 			  be32_to_cpu(ohci->config_rom[2]));
1990 		ohci->config_rom[0] = ohci->next_header;
1991 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1992 			  be32_to_cpu(ohci->next_header));
1993 	}
1994 
1995 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1996 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1997 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1998 #endif
1999 
2000 	spin_unlock_irq(&ohci->lock);
2001 
2002 	if (free_rom)
2003 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2004 				  free_rom, free_rom_bus);
2005 
2006 	log_selfids(ohci, generation, self_id_count);
2007 
2008 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2009 				 self_id_count, ohci->self_id_buffer,
2010 				 ohci->csr_state_setclear_abdicate);
2011 	ohci->csr_state_setclear_abdicate = false;
2012 }
2013 
2014 static irqreturn_t irq_handler(int irq, void *data)
2015 {
2016 	struct fw_ohci *ohci = data;
2017 	u32 event, iso_event;
2018 	int i;
2019 
2020 	event = reg_read(ohci, OHCI1394_IntEventClear);
2021 
2022 	if (!event || !~event)
2023 		return IRQ_NONE;
2024 
2025 	/*
2026 	 * busReset and postedWriteErr must not be cleared yet
2027 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2028 	 */
2029 	reg_write(ohci, OHCI1394_IntEventClear,
2030 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2031 	log_irqs(ohci, event);
2032 
2033 	if (event & OHCI1394_selfIDComplete)
2034 		queue_work(fw_workqueue, &ohci->bus_reset_work);
2035 
2036 	if (event & OHCI1394_RQPkt)
2037 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2038 
2039 	if (event & OHCI1394_RSPkt)
2040 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2041 
2042 	if (event & OHCI1394_reqTxComplete)
2043 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
2044 
2045 	if (event & OHCI1394_respTxComplete)
2046 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
2047 
2048 	if (event & OHCI1394_isochRx) {
2049 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2050 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2051 
2052 		while (iso_event) {
2053 			i = ffs(iso_event) - 1;
2054 			tasklet_schedule(
2055 				&ohci->ir_context_list[i].context.tasklet);
2056 			iso_event &= ~(1 << i);
2057 		}
2058 	}
2059 
2060 	if (event & OHCI1394_isochTx) {
2061 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2062 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2063 
2064 		while (iso_event) {
2065 			i = ffs(iso_event) - 1;
2066 			tasklet_schedule(
2067 				&ohci->it_context_list[i].context.tasklet);
2068 			iso_event &= ~(1 << i);
2069 		}
2070 	}
2071 
2072 	if (unlikely(event & OHCI1394_regAccessFail))
2073 		dev_err(ohci->card.device, "register access failure\n");
2074 
2075 	if (unlikely(event & OHCI1394_postedWriteErr)) {
2076 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2077 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2078 		reg_write(ohci, OHCI1394_IntEventClear,
2079 			  OHCI1394_postedWriteErr);
2080 		if (printk_ratelimit())
2081 			dev_err(ohci->card.device, "PCI posted write error\n");
2082 	}
2083 
2084 	if (unlikely(event & OHCI1394_cycleTooLong)) {
2085 		if (printk_ratelimit())
2086 			dev_notice(ohci->card.device,
2087 				   "isochronous cycle too long\n");
2088 		reg_write(ohci, OHCI1394_LinkControlSet,
2089 			  OHCI1394_LinkControl_cycleMaster);
2090 	}
2091 
2092 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
2093 		/*
2094 		 * We need to clear this event bit in order to make
2095 		 * cycleMatch isochronous I/O work.  In theory we should
2096 		 * stop active cycleMatch iso contexts now and restart
2097 		 * them at least two cycles later.  (FIXME?)
2098 		 */
2099 		if (printk_ratelimit())
2100 			dev_notice(ohci->card.device,
2101 				   "isochronous cycle inconsistent\n");
2102 	}
2103 
2104 	if (unlikely(event & OHCI1394_unrecoverableError))
2105 		handle_dead_contexts(ohci);
2106 
2107 	if (event & OHCI1394_cycle64Seconds) {
2108 		spin_lock(&ohci->lock);
2109 		update_bus_time(ohci);
2110 		spin_unlock(&ohci->lock);
2111 	} else
2112 		flush_writes(ohci);
2113 
2114 	return IRQ_HANDLED;
2115 }
2116 
2117 static int software_reset(struct fw_ohci *ohci)
2118 {
2119 	u32 val;
2120 	int i;
2121 
2122 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2123 	for (i = 0; i < 500; i++) {
2124 		val = reg_read(ohci, OHCI1394_HCControlSet);
2125 		if (!~val)
2126 			return -ENODEV; /* Card was ejected. */
2127 
2128 		if (!(val & OHCI1394_HCControl_softReset))
2129 			return 0;
2130 
2131 		msleep(1);
2132 	}
2133 
2134 	return -EBUSY;
2135 }
2136 
2137 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2138 {
2139 	size_t size = length * 4;
2140 
2141 	memcpy(dest, src, size);
2142 	if (size < CONFIG_ROM_SIZE)
2143 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2144 }
2145 
2146 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2147 {
2148 	bool enable_1394a;
2149 	int ret, clear, set, offset;
2150 
2151 	/* Check if the driver should configure link and PHY. */
2152 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2153 	      OHCI1394_HCControl_programPhyEnable))
2154 		return 0;
2155 
2156 	/* Paranoia: check whether the PHY supports 1394a, too. */
2157 	enable_1394a = false;
2158 	ret = read_phy_reg(ohci, 2);
2159 	if (ret < 0)
2160 		return ret;
2161 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2162 		ret = read_paged_phy_reg(ohci, 1, 8);
2163 		if (ret < 0)
2164 			return ret;
2165 		if (ret >= 1)
2166 			enable_1394a = true;
2167 	}
2168 
2169 	if (ohci->quirks & QUIRK_NO_1394A)
2170 		enable_1394a = false;
2171 
2172 	/* Configure PHY and link consistently. */
2173 	if (enable_1394a) {
2174 		clear = 0;
2175 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2176 	} else {
2177 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2178 		set = 0;
2179 	}
2180 	ret = update_phy_reg(ohci, 5, clear, set);
2181 	if (ret < 0)
2182 		return ret;
2183 
2184 	if (enable_1394a)
2185 		offset = OHCI1394_HCControlSet;
2186 	else
2187 		offset = OHCI1394_HCControlClear;
2188 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2189 
2190 	/* Clean up: configuration has been taken care of. */
2191 	reg_write(ohci, OHCI1394_HCControlClear,
2192 		  OHCI1394_HCControl_programPhyEnable);
2193 
2194 	return 0;
2195 }
2196 
2197 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2198 {
2199 	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2200 	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2201 	int reg, i;
2202 
2203 	reg = read_phy_reg(ohci, 2);
2204 	if (reg < 0)
2205 		return reg;
2206 	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2207 		return 0;
2208 
2209 	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2210 		reg = read_paged_phy_reg(ohci, 1, i + 10);
2211 		if (reg < 0)
2212 			return reg;
2213 		if (reg != id[i])
2214 			return 0;
2215 	}
2216 	return 1;
2217 }
2218 
2219 static int ohci_enable(struct fw_card *card,
2220 		       const __be32 *config_rom, size_t length)
2221 {
2222 	struct fw_ohci *ohci = fw_ohci(card);
2223 	struct pci_dev *dev = to_pci_dev(card->device);
2224 	u32 lps, version, irqs;
2225 	int i, ret;
2226 
2227 	if (software_reset(ohci)) {
2228 		dev_err(card->device, "failed to reset ohci card\n");
2229 		return -EBUSY;
2230 	}
2231 
2232 	/*
2233 	 * Now enable LPS, which we need in order to start accessing
2234 	 * most of the registers.  In fact, on some cards (ALI M5251),
2235 	 * accessing registers in the SClk domain without LPS enabled
2236 	 * will lock up the machine.  Wait 50msec to make sure we have
2237 	 * full link enabled.  However, with some cards (well, at least
2238 	 * a JMicron PCIe card), we have to try again sometimes.
2239 	 */
2240 	reg_write(ohci, OHCI1394_HCControlSet,
2241 		  OHCI1394_HCControl_LPS |
2242 		  OHCI1394_HCControl_postedWriteEnable);
2243 	flush_writes(ohci);
2244 
2245 	for (lps = 0, i = 0; !lps && i < 3; i++) {
2246 		msleep(50);
2247 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2248 		      OHCI1394_HCControl_LPS;
2249 	}
2250 
2251 	if (!lps) {
2252 		dev_err(card->device, "failed to set Link Power Status\n");
2253 		return -EIO;
2254 	}
2255 
2256 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2257 		ret = probe_tsb41ba3d(ohci);
2258 		if (ret < 0)
2259 			return ret;
2260 		if (ret)
2261 			dev_notice(card->device, "local TSB41BA3D phy\n");
2262 		else
2263 			ohci->quirks &= ~QUIRK_TI_SLLZ059;
2264 	}
2265 
2266 	reg_write(ohci, OHCI1394_HCControlClear,
2267 		  OHCI1394_HCControl_noByteSwapData);
2268 
2269 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2270 	reg_write(ohci, OHCI1394_LinkControlSet,
2271 		  OHCI1394_LinkControl_cycleTimerEnable |
2272 		  OHCI1394_LinkControl_cycleMaster);
2273 
2274 	reg_write(ohci, OHCI1394_ATRetries,
2275 		  OHCI1394_MAX_AT_REQ_RETRIES |
2276 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2277 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2278 		  (200 << 16));
2279 
2280 	ohci->bus_time_running = false;
2281 
2282 	for (i = 0; i < 32; i++)
2283 		if (ohci->ir_context_support & (1 << i))
2284 			reg_write(ohci, OHCI1394_IsoRcvContextControlClear(i),
2285 				  IR_CONTEXT_MULTI_CHANNEL_MODE);
2286 
2287 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2288 	if (version >= OHCI_VERSION_1_1) {
2289 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2290 			  0xfffffffe);
2291 		card->broadcast_channel_auto_allocated = true;
2292 	}
2293 
2294 	/* Get implemented bits of the priority arbitration request counter. */
2295 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2296 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2297 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2298 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2299 
2300 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
2301 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2302 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2303 
2304 	ret = configure_1394a_enhancements(ohci);
2305 	if (ret < 0)
2306 		return ret;
2307 
2308 	/* Activate link_on bit and contender bit in our self ID packets.*/
2309 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2310 	if (ret < 0)
2311 		return ret;
2312 
2313 	/*
2314 	 * When the link is not yet enabled, the atomic config rom
2315 	 * update mechanism described below in ohci_set_config_rom()
2316 	 * is not active.  We have to update ConfigRomHeader and
2317 	 * BusOptions manually, and the write to ConfigROMmap takes
2318 	 * effect immediately.  We tie this to the enabling of the
2319 	 * link, so we have a valid config rom before enabling - the
2320 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2321 	 * values before enabling.
2322 	 *
2323 	 * However, when the ConfigROMmap is written, some controllers
2324 	 * always read back quadlets 0 and 2 from the config rom to
2325 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2326 	 * They shouldn't do that in this initial case where the link
2327 	 * isn't enabled.  This means we have to use the same
2328 	 * workaround here, setting the bus header to 0 and then write
2329 	 * the right values in the bus reset tasklet.
2330 	 */
2331 
2332 	if (config_rom) {
2333 		ohci->next_config_rom =
2334 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2335 					   &ohci->next_config_rom_bus,
2336 					   GFP_KERNEL);
2337 		if (ohci->next_config_rom == NULL)
2338 			return -ENOMEM;
2339 
2340 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2341 	} else {
2342 		/*
2343 		 * In the suspend case, config_rom is NULL, which
2344 		 * means that we just reuse the old config rom.
2345 		 */
2346 		ohci->next_config_rom = ohci->config_rom;
2347 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2348 	}
2349 
2350 	ohci->next_header = ohci->next_config_rom[0];
2351 	ohci->next_config_rom[0] = 0;
2352 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2353 	reg_write(ohci, OHCI1394_BusOptions,
2354 		  be32_to_cpu(ohci->next_config_rom[2]));
2355 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2356 
2357 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2358 
2359 	if (!(ohci->quirks & QUIRK_NO_MSI))
2360 		pci_enable_msi(dev);
2361 	if (request_irq(dev->irq, irq_handler,
2362 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
2363 			ohci_driver_name, ohci)) {
2364 		dev_err(card->device, "failed to allocate interrupt %d\n",
2365 			dev->irq);
2366 		pci_disable_msi(dev);
2367 
2368 		if (config_rom) {
2369 			dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2370 					  ohci->next_config_rom,
2371 					  ohci->next_config_rom_bus);
2372 			ohci->next_config_rom = NULL;
2373 		}
2374 		return -EIO;
2375 	}
2376 
2377 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2378 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2379 		OHCI1394_isochTx | OHCI1394_isochRx |
2380 		OHCI1394_postedWriteErr |
2381 		OHCI1394_selfIDComplete |
2382 		OHCI1394_regAccessFail |
2383 		OHCI1394_cycleInconsistent |
2384 		OHCI1394_unrecoverableError |
2385 		OHCI1394_cycleTooLong |
2386 		OHCI1394_masterIntEnable;
2387 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2388 		irqs |= OHCI1394_busReset;
2389 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2390 
2391 	reg_write(ohci, OHCI1394_HCControlSet,
2392 		  OHCI1394_HCControl_linkEnable |
2393 		  OHCI1394_HCControl_BIBimageValid);
2394 
2395 	reg_write(ohci, OHCI1394_LinkControlSet,
2396 		  OHCI1394_LinkControl_rcvSelfID |
2397 		  OHCI1394_LinkControl_rcvPhyPkt);
2398 
2399 	ar_context_run(&ohci->ar_request_ctx);
2400 	ar_context_run(&ohci->ar_response_ctx);
2401 
2402 	flush_writes(ohci);
2403 
2404 	/* We are ready to go, reset bus to finish initialization. */
2405 	fw_schedule_bus_reset(&ohci->card, false, true);
2406 
2407 	return 0;
2408 }
2409 
2410 static int ohci_set_config_rom(struct fw_card *card,
2411 			       const __be32 *config_rom, size_t length)
2412 {
2413 	struct fw_ohci *ohci;
2414 	__be32 *next_config_rom;
2415 	dma_addr_t uninitialized_var(next_config_rom_bus);
2416 
2417 	ohci = fw_ohci(card);
2418 
2419 	/*
2420 	 * When the OHCI controller is enabled, the config rom update
2421 	 * mechanism is a bit tricky, but easy enough to use.  See
2422 	 * section 5.5.6 in the OHCI specification.
2423 	 *
2424 	 * The OHCI controller caches the new config rom address in a
2425 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2426 	 * for the changes to take place.  When the bus reset is
2427 	 * detected, the controller loads the new values for the
2428 	 * ConfigRomHeader and BusOptions registers from the specified
2429 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2430 	 * shadow register. All automatically and atomically.
2431 	 *
2432 	 * Now, there's a twist to this story.  The automatic load of
2433 	 * ConfigRomHeader and BusOptions doesn't honor the
2434 	 * noByteSwapData bit, so with a be32 config rom, the
2435 	 * controller will load be32 values in to these registers
2436 	 * during the atomic update, even on litte endian
2437 	 * architectures.  The workaround we use is to put a 0 in the
2438 	 * header quadlet; 0 is endian agnostic and means that the
2439 	 * config rom isn't ready yet.  In the bus reset tasklet we
2440 	 * then set up the real values for the two registers.
2441 	 *
2442 	 * We use ohci->lock to avoid racing with the code that sets
2443 	 * ohci->next_config_rom to NULL (see bus_reset_work).
2444 	 */
2445 
2446 	next_config_rom =
2447 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2448 				   &next_config_rom_bus, GFP_KERNEL);
2449 	if (next_config_rom == NULL)
2450 		return -ENOMEM;
2451 
2452 	spin_lock_irq(&ohci->lock);
2453 
2454 	/*
2455 	 * If there is not an already pending config_rom update,
2456 	 * push our new allocation into the ohci->next_config_rom
2457 	 * and then mark the local variable as null so that we
2458 	 * won't deallocate the new buffer.
2459 	 *
2460 	 * OTOH, if there is a pending config_rom update, just
2461 	 * use that buffer with the new config_rom data, and
2462 	 * let this routine free the unused DMA allocation.
2463 	 */
2464 
2465 	if (ohci->next_config_rom == NULL) {
2466 		ohci->next_config_rom = next_config_rom;
2467 		ohci->next_config_rom_bus = next_config_rom_bus;
2468 		next_config_rom = NULL;
2469 	}
2470 
2471 	copy_config_rom(ohci->next_config_rom, config_rom, length);
2472 
2473 	ohci->next_header = config_rom[0];
2474 	ohci->next_config_rom[0] = 0;
2475 
2476 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2477 
2478 	spin_unlock_irq(&ohci->lock);
2479 
2480 	/* If we didn't use the DMA allocation, delete it. */
2481 	if (next_config_rom != NULL)
2482 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2483 				  next_config_rom, next_config_rom_bus);
2484 
2485 	/*
2486 	 * Now initiate a bus reset to have the changes take
2487 	 * effect. We clean up the old config rom memory and DMA
2488 	 * mappings in the bus reset tasklet, since the OHCI
2489 	 * controller could need to access it before the bus reset
2490 	 * takes effect.
2491 	 */
2492 
2493 	fw_schedule_bus_reset(&ohci->card, true, true);
2494 
2495 	return 0;
2496 }
2497 
2498 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2499 {
2500 	struct fw_ohci *ohci = fw_ohci(card);
2501 
2502 	at_context_transmit(&ohci->at_request_ctx, packet);
2503 }
2504 
2505 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2506 {
2507 	struct fw_ohci *ohci = fw_ohci(card);
2508 
2509 	at_context_transmit(&ohci->at_response_ctx, packet);
2510 }
2511 
2512 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2513 {
2514 	struct fw_ohci *ohci = fw_ohci(card);
2515 	struct context *ctx = &ohci->at_request_ctx;
2516 	struct driver_data *driver_data = packet->driver_data;
2517 	int ret = -ENOENT;
2518 
2519 	tasklet_disable(&ctx->tasklet);
2520 
2521 	if (packet->ack != 0)
2522 		goto out;
2523 
2524 	if (packet->payload_mapped)
2525 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2526 				 packet->payload_length, DMA_TO_DEVICE);
2527 
2528 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2529 	driver_data->packet = NULL;
2530 	packet->ack = RCODE_CANCELLED;
2531 	packet->callback(packet, &ohci->card, packet->ack);
2532 	ret = 0;
2533  out:
2534 	tasklet_enable(&ctx->tasklet);
2535 
2536 	return ret;
2537 }
2538 
2539 static int ohci_enable_phys_dma(struct fw_card *card,
2540 				int node_id, int generation)
2541 {
2542 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2543 	return 0;
2544 #else
2545 	struct fw_ohci *ohci = fw_ohci(card);
2546 	unsigned long flags;
2547 	int n, ret = 0;
2548 
2549 	/*
2550 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2551 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2552 	 */
2553 
2554 	spin_lock_irqsave(&ohci->lock, flags);
2555 
2556 	if (ohci->generation != generation) {
2557 		ret = -ESTALE;
2558 		goto out;
2559 	}
2560 
2561 	/*
2562 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2563 	 * enabled for _all_ nodes on remote buses.
2564 	 */
2565 
2566 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2567 	if (n < 32)
2568 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2569 	else
2570 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2571 
2572 	flush_writes(ohci);
2573  out:
2574 	spin_unlock_irqrestore(&ohci->lock, flags);
2575 
2576 	return ret;
2577 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2578 }
2579 
2580 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2581 {
2582 	struct fw_ohci *ohci = fw_ohci(card);
2583 	unsigned long flags;
2584 	u32 value;
2585 
2586 	switch (csr_offset) {
2587 	case CSR_STATE_CLEAR:
2588 	case CSR_STATE_SET:
2589 		if (ohci->is_root &&
2590 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2591 		     OHCI1394_LinkControl_cycleMaster))
2592 			value = CSR_STATE_BIT_CMSTR;
2593 		else
2594 			value = 0;
2595 		if (ohci->csr_state_setclear_abdicate)
2596 			value |= CSR_STATE_BIT_ABDICATE;
2597 
2598 		return value;
2599 
2600 	case CSR_NODE_IDS:
2601 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2602 
2603 	case CSR_CYCLE_TIME:
2604 		return get_cycle_time(ohci);
2605 
2606 	case CSR_BUS_TIME:
2607 		/*
2608 		 * We might be called just after the cycle timer has wrapped
2609 		 * around but just before the cycle64Seconds handler, so we
2610 		 * better check here, too, if the bus time needs to be updated.
2611 		 */
2612 		spin_lock_irqsave(&ohci->lock, flags);
2613 		value = update_bus_time(ohci);
2614 		spin_unlock_irqrestore(&ohci->lock, flags);
2615 		return value;
2616 
2617 	case CSR_BUSY_TIMEOUT:
2618 		value = reg_read(ohci, OHCI1394_ATRetries);
2619 		return (value >> 4) & 0x0ffff00f;
2620 
2621 	case CSR_PRIORITY_BUDGET:
2622 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2623 			(ohci->pri_req_max << 8);
2624 
2625 	default:
2626 		WARN_ON(1);
2627 		return 0;
2628 	}
2629 }
2630 
2631 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2632 {
2633 	struct fw_ohci *ohci = fw_ohci(card);
2634 	unsigned long flags;
2635 
2636 	switch (csr_offset) {
2637 	case CSR_STATE_CLEAR:
2638 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2639 			reg_write(ohci, OHCI1394_LinkControlClear,
2640 				  OHCI1394_LinkControl_cycleMaster);
2641 			flush_writes(ohci);
2642 		}
2643 		if (value & CSR_STATE_BIT_ABDICATE)
2644 			ohci->csr_state_setclear_abdicate = false;
2645 		break;
2646 
2647 	case CSR_STATE_SET:
2648 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2649 			reg_write(ohci, OHCI1394_LinkControlSet,
2650 				  OHCI1394_LinkControl_cycleMaster);
2651 			flush_writes(ohci);
2652 		}
2653 		if (value & CSR_STATE_BIT_ABDICATE)
2654 			ohci->csr_state_setclear_abdicate = true;
2655 		break;
2656 
2657 	case CSR_NODE_IDS:
2658 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2659 		flush_writes(ohci);
2660 		break;
2661 
2662 	case CSR_CYCLE_TIME:
2663 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2664 		reg_write(ohci, OHCI1394_IntEventSet,
2665 			  OHCI1394_cycleInconsistent);
2666 		flush_writes(ohci);
2667 		break;
2668 
2669 	case CSR_BUS_TIME:
2670 		spin_lock_irqsave(&ohci->lock, flags);
2671 		ohci->bus_time = (update_bus_time(ohci) & 0x40) |
2672 		                 (value & ~0x7f);
2673 		spin_unlock_irqrestore(&ohci->lock, flags);
2674 		break;
2675 
2676 	case CSR_BUSY_TIMEOUT:
2677 		value = (value & 0xf) | ((value & 0xf) << 4) |
2678 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2679 		reg_write(ohci, OHCI1394_ATRetries, value);
2680 		flush_writes(ohci);
2681 		break;
2682 
2683 	case CSR_PRIORITY_BUDGET:
2684 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2685 		flush_writes(ohci);
2686 		break;
2687 
2688 	default:
2689 		WARN_ON(1);
2690 		break;
2691 	}
2692 }
2693 
2694 static void flush_iso_completions(struct iso_context *ctx)
2695 {
2696 	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2697 			      ctx->header_length, ctx->header,
2698 			      ctx->base.callback_data);
2699 	ctx->header_length = 0;
2700 }
2701 
2702 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2703 {
2704 	u32 *ctx_hdr;
2705 
2706 	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE)
2707 		flush_iso_completions(ctx);
2708 
2709 	ctx_hdr = ctx->header + ctx->header_length;
2710 	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2711 
2712 	/*
2713 	 * The two iso header quadlets are byteswapped to little
2714 	 * endian by the controller, but we want to present them
2715 	 * as big endian for consistency with the bus endianness.
2716 	 */
2717 	if (ctx->base.header_size > 0)
2718 		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2719 	if (ctx->base.header_size > 4)
2720 		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2721 	if (ctx->base.header_size > 8)
2722 		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2723 	ctx->header_length += ctx->base.header_size;
2724 }
2725 
2726 static int handle_ir_packet_per_buffer(struct context *context,
2727 				       struct descriptor *d,
2728 				       struct descriptor *last)
2729 {
2730 	struct iso_context *ctx =
2731 		container_of(context, struct iso_context, context);
2732 	struct descriptor *pd;
2733 	u32 buffer_dma;
2734 
2735 	for (pd = d; pd <= last; pd++)
2736 		if (pd->transfer_status)
2737 			break;
2738 	if (pd > last)
2739 		/* Descriptor(s) not done yet, stop iteration */
2740 		return 0;
2741 
2742 	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2743 		d++;
2744 		buffer_dma = le32_to_cpu(d->data_address);
2745 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2746 					      buffer_dma & PAGE_MASK,
2747 					      buffer_dma & ~PAGE_MASK,
2748 					      le16_to_cpu(d->req_count),
2749 					      DMA_FROM_DEVICE);
2750 	}
2751 
2752 	copy_iso_headers(ctx, (u32 *) (last + 1));
2753 
2754 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2755 		flush_iso_completions(ctx);
2756 
2757 	return 1;
2758 }
2759 
2760 /* d == last because each descriptor block is only a single descriptor. */
2761 static int handle_ir_buffer_fill(struct context *context,
2762 				 struct descriptor *d,
2763 				 struct descriptor *last)
2764 {
2765 	struct iso_context *ctx =
2766 		container_of(context, struct iso_context, context);
2767 	unsigned int req_count, res_count, completed;
2768 	u32 buffer_dma;
2769 
2770 	req_count = le16_to_cpu(last->req_count);
2771 	res_count = le16_to_cpu(ACCESS_ONCE(last->res_count));
2772 	completed = req_count - res_count;
2773 	buffer_dma = le32_to_cpu(last->data_address);
2774 
2775 	if (completed > 0) {
2776 		ctx->mc_buffer_bus = buffer_dma;
2777 		ctx->mc_completed = completed;
2778 	}
2779 
2780 	if (res_count != 0)
2781 		/* Descriptor(s) not done yet, stop iteration */
2782 		return 0;
2783 
2784 	dma_sync_single_range_for_cpu(context->ohci->card.device,
2785 				      buffer_dma & PAGE_MASK,
2786 				      buffer_dma & ~PAGE_MASK,
2787 				      completed, DMA_FROM_DEVICE);
2788 
2789 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2790 		ctx->base.callback.mc(&ctx->base,
2791 				      buffer_dma + completed,
2792 				      ctx->base.callback_data);
2793 		ctx->mc_completed = 0;
2794 	}
2795 
2796 	return 1;
2797 }
2798 
2799 static void flush_ir_buffer_fill(struct iso_context *ctx)
2800 {
2801 	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
2802 				      ctx->mc_buffer_bus & PAGE_MASK,
2803 				      ctx->mc_buffer_bus & ~PAGE_MASK,
2804 				      ctx->mc_completed, DMA_FROM_DEVICE);
2805 
2806 	ctx->base.callback.mc(&ctx->base,
2807 			      ctx->mc_buffer_bus + ctx->mc_completed,
2808 			      ctx->base.callback_data);
2809 	ctx->mc_completed = 0;
2810 }
2811 
2812 static inline void sync_it_packet_for_cpu(struct context *context,
2813 					  struct descriptor *pd)
2814 {
2815 	__le16 control;
2816 	u32 buffer_dma;
2817 
2818 	/* only packets beginning with OUTPUT_MORE* have data buffers */
2819 	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2820 		return;
2821 
2822 	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
2823 	pd += 2;
2824 
2825 	/*
2826 	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
2827 	 * data buffer is in the context program's coherent page and must not
2828 	 * be synced.
2829 	 */
2830 	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
2831 	    (context->current_bus          & PAGE_MASK)) {
2832 		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2833 			return;
2834 		pd++;
2835 	}
2836 
2837 	do {
2838 		buffer_dma = le32_to_cpu(pd->data_address);
2839 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2840 					      buffer_dma & PAGE_MASK,
2841 					      buffer_dma & ~PAGE_MASK,
2842 					      le16_to_cpu(pd->req_count),
2843 					      DMA_TO_DEVICE);
2844 		control = pd->control;
2845 		pd++;
2846 	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
2847 }
2848 
2849 static int handle_it_packet(struct context *context,
2850 			    struct descriptor *d,
2851 			    struct descriptor *last)
2852 {
2853 	struct iso_context *ctx =
2854 		container_of(context, struct iso_context, context);
2855 	struct descriptor *pd;
2856 	__be32 *ctx_hdr;
2857 
2858 	for (pd = d; pd <= last; pd++)
2859 		if (pd->transfer_status)
2860 			break;
2861 	if (pd > last)
2862 		/* Descriptor(s) not done yet, stop iteration */
2863 		return 0;
2864 
2865 	sync_it_packet_for_cpu(context, d);
2866 
2867 	if (ctx->header_length + 4 > PAGE_SIZE)
2868 		flush_iso_completions(ctx);
2869 
2870 	ctx_hdr = ctx->header + ctx->header_length;
2871 	ctx->last_timestamp = le16_to_cpu(last->res_count);
2872 	/* Present this value as big-endian to match the receive code */
2873 	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
2874 			       le16_to_cpu(pd->res_count));
2875 	ctx->header_length += 4;
2876 
2877 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2878 		flush_iso_completions(ctx);
2879 
2880 	return 1;
2881 }
2882 
2883 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2884 {
2885 	u32 hi = channels >> 32, lo = channels;
2886 
2887 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2888 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2889 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2890 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2891 	mmiowb();
2892 	ohci->mc_channels = channels;
2893 }
2894 
2895 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2896 				int type, int channel, size_t header_size)
2897 {
2898 	struct fw_ohci *ohci = fw_ohci(card);
2899 	struct iso_context *uninitialized_var(ctx);
2900 	descriptor_callback_t uninitialized_var(callback);
2901 	u64 *uninitialized_var(channels);
2902 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2903 	int index, ret = -EBUSY;
2904 
2905 	spin_lock_irq(&ohci->lock);
2906 
2907 	switch (type) {
2908 	case FW_ISO_CONTEXT_TRANSMIT:
2909 		mask     = &ohci->it_context_mask;
2910 		callback = handle_it_packet;
2911 		index    = ffs(*mask) - 1;
2912 		if (index >= 0) {
2913 			*mask &= ~(1 << index);
2914 			regs = OHCI1394_IsoXmitContextBase(index);
2915 			ctx  = &ohci->it_context_list[index];
2916 		}
2917 		break;
2918 
2919 	case FW_ISO_CONTEXT_RECEIVE:
2920 		channels = &ohci->ir_context_channels;
2921 		mask     = &ohci->ir_context_mask;
2922 		callback = handle_ir_packet_per_buffer;
2923 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2924 		if (index >= 0) {
2925 			*channels &= ~(1ULL << channel);
2926 			*mask     &= ~(1 << index);
2927 			regs = OHCI1394_IsoRcvContextBase(index);
2928 			ctx  = &ohci->ir_context_list[index];
2929 		}
2930 		break;
2931 
2932 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2933 		mask     = &ohci->ir_context_mask;
2934 		callback = handle_ir_buffer_fill;
2935 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2936 		if (index >= 0) {
2937 			ohci->mc_allocated = true;
2938 			*mask &= ~(1 << index);
2939 			regs = OHCI1394_IsoRcvContextBase(index);
2940 			ctx  = &ohci->ir_context_list[index];
2941 		}
2942 		break;
2943 
2944 	default:
2945 		index = -1;
2946 		ret = -ENOSYS;
2947 	}
2948 
2949 	spin_unlock_irq(&ohci->lock);
2950 
2951 	if (index < 0)
2952 		return ERR_PTR(ret);
2953 
2954 	memset(ctx, 0, sizeof(*ctx));
2955 	ctx->header_length = 0;
2956 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2957 	if (ctx->header == NULL) {
2958 		ret = -ENOMEM;
2959 		goto out;
2960 	}
2961 	ret = context_init(&ctx->context, ohci, regs, callback);
2962 	if (ret < 0)
2963 		goto out_with_header;
2964 
2965 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
2966 		set_multichannel_mask(ohci, 0);
2967 		ctx->mc_completed = 0;
2968 	}
2969 
2970 	return &ctx->base;
2971 
2972  out_with_header:
2973 	free_page((unsigned long)ctx->header);
2974  out:
2975 	spin_lock_irq(&ohci->lock);
2976 
2977 	switch (type) {
2978 	case FW_ISO_CONTEXT_RECEIVE:
2979 		*channels |= 1ULL << channel;
2980 		break;
2981 
2982 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2983 		ohci->mc_allocated = false;
2984 		break;
2985 	}
2986 	*mask |= 1 << index;
2987 
2988 	spin_unlock_irq(&ohci->lock);
2989 
2990 	return ERR_PTR(ret);
2991 }
2992 
2993 static int ohci_start_iso(struct fw_iso_context *base,
2994 			  s32 cycle, u32 sync, u32 tags)
2995 {
2996 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2997 	struct fw_ohci *ohci = ctx->context.ohci;
2998 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2999 	int index;
3000 
3001 	/* the controller cannot start without any queued packets */
3002 	if (ctx->context.last->branch_address == 0)
3003 		return -ENODATA;
3004 
3005 	switch (ctx->base.type) {
3006 	case FW_ISO_CONTEXT_TRANSMIT:
3007 		index = ctx - ohci->it_context_list;
3008 		match = 0;
3009 		if (cycle >= 0)
3010 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3011 				(cycle & 0x7fff) << 16;
3012 
3013 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3014 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3015 		context_run(&ctx->context, match);
3016 		break;
3017 
3018 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3019 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3020 		/* fall through */
3021 	case FW_ISO_CONTEXT_RECEIVE:
3022 		index = ctx - ohci->ir_context_list;
3023 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
3024 		if (cycle >= 0) {
3025 			match |= (cycle & 0x07fff) << 12;
3026 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3027 		}
3028 
3029 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3030 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3031 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3032 		context_run(&ctx->context, control);
3033 
3034 		ctx->sync = sync;
3035 		ctx->tags = tags;
3036 
3037 		break;
3038 	}
3039 
3040 	return 0;
3041 }
3042 
3043 static int ohci_stop_iso(struct fw_iso_context *base)
3044 {
3045 	struct fw_ohci *ohci = fw_ohci(base->card);
3046 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3047 	int index;
3048 
3049 	switch (ctx->base.type) {
3050 	case FW_ISO_CONTEXT_TRANSMIT:
3051 		index = ctx - ohci->it_context_list;
3052 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3053 		break;
3054 
3055 	case FW_ISO_CONTEXT_RECEIVE:
3056 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3057 		index = ctx - ohci->ir_context_list;
3058 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3059 		break;
3060 	}
3061 	flush_writes(ohci);
3062 	context_stop(&ctx->context);
3063 	tasklet_kill(&ctx->context.tasklet);
3064 
3065 	return 0;
3066 }
3067 
3068 static void ohci_free_iso_context(struct fw_iso_context *base)
3069 {
3070 	struct fw_ohci *ohci = fw_ohci(base->card);
3071 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3072 	unsigned long flags;
3073 	int index;
3074 
3075 	ohci_stop_iso(base);
3076 	context_release(&ctx->context);
3077 	free_page((unsigned long)ctx->header);
3078 
3079 	spin_lock_irqsave(&ohci->lock, flags);
3080 
3081 	switch (base->type) {
3082 	case FW_ISO_CONTEXT_TRANSMIT:
3083 		index = ctx - ohci->it_context_list;
3084 		ohci->it_context_mask |= 1 << index;
3085 		break;
3086 
3087 	case FW_ISO_CONTEXT_RECEIVE:
3088 		index = ctx - ohci->ir_context_list;
3089 		ohci->ir_context_mask |= 1 << index;
3090 		ohci->ir_context_channels |= 1ULL << base->channel;
3091 		break;
3092 
3093 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3094 		index = ctx - ohci->ir_context_list;
3095 		ohci->ir_context_mask |= 1 << index;
3096 		ohci->ir_context_channels |= ohci->mc_channels;
3097 		ohci->mc_channels = 0;
3098 		ohci->mc_allocated = false;
3099 		break;
3100 	}
3101 
3102 	spin_unlock_irqrestore(&ohci->lock, flags);
3103 }
3104 
3105 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3106 {
3107 	struct fw_ohci *ohci = fw_ohci(base->card);
3108 	unsigned long flags;
3109 	int ret;
3110 
3111 	switch (base->type) {
3112 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3113 
3114 		spin_lock_irqsave(&ohci->lock, flags);
3115 
3116 		/* Don't allow multichannel to grab other contexts' channels. */
3117 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3118 			*channels = ohci->ir_context_channels;
3119 			ret = -EBUSY;
3120 		} else {
3121 			set_multichannel_mask(ohci, *channels);
3122 			ret = 0;
3123 		}
3124 
3125 		spin_unlock_irqrestore(&ohci->lock, flags);
3126 
3127 		break;
3128 	default:
3129 		ret = -EINVAL;
3130 	}
3131 
3132 	return ret;
3133 }
3134 
3135 #ifdef CONFIG_PM
3136 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3137 {
3138 	int i;
3139 	struct iso_context *ctx;
3140 
3141 	for (i = 0 ; i < ohci->n_ir ; i++) {
3142 		ctx = &ohci->ir_context_list[i];
3143 		if (ctx->context.running)
3144 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3145 	}
3146 
3147 	for (i = 0 ; i < ohci->n_it ; i++) {
3148 		ctx = &ohci->it_context_list[i];
3149 		if (ctx->context.running)
3150 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3151 	}
3152 }
3153 #endif
3154 
3155 static int queue_iso_transmit(struct iso_context *ctx,
3156 			      struct fw_iso_packet *packet,
3157 			      struct fw_iso_buffer *buffer,
3158 			      unsigned long payload)
3159 {
3160 	struct descriptor *d, *last, *pd;
3161 	struct fw_iso_packet *p;
3162 	__le32 *header;
3163 	dma_addr_t d_bus, page_bus;
3164 	u32 z, header_z, payload_z, irq;
3165 	u32 payload_index, payload_end_index, next_page_index;
3166 	int page, end_page, i, length, offset;
3167 
3168 	p = packet;
3169 	payload_index = payload;
3170 
3171 	if (p->skip)
3172 		z = 1;
3173 	else
3174 		z = 2;
3175 	if (p->header_length > 0)
3176 		z++;
3177 
3178 	/* Determine the first page the payload isn't contained in. */
3179 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3180 	if (p->payload_length > 0)
3181 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
3182 	else
3183 		payload_z = 0;
3184 
3185 	z += payload_z;
3186 
3187 	/* Get header size in number of descriptors. */
3188 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3189 
3190 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3191 	if (d == NULL)
3192 		return -ENOMEM;
3193 
3194 	if (!p->skip) {
3195 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3196 		d[0].req_count = cpu_to_le16(8);
3197 		/*
3198 		 * Link the skip address to this descriptor itself.  This causes
3199 		 * a context to skip a cycle whenever lost cycles or FIFO
3200 		 * overruns occur, without dropping the data.  The application
3201 		 * should then decide whether this is an error condition or not.
3202 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
3203 		 */
3204 		d[0].branch_address = cpu_to_le32(d_bus | z);
3205 
3206 		header = (__le32 *) &d[1];
3207 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
3208 					IT_HEADER_TAG(p->tag) |
3209 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
3210 					IT_HEADER_CHANNEL(ctx->base.channel) |
3211 					IT_HEADER_SPEED(ctx->base.speed));
3212 		header[1] =
3213 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
3214 							  p->payload_length));
3215 	}
3216 
3217 	if (p->header_length > 0) {
3218 		d[2].req_count    = cpu_to_le16(p->header_length);
3219 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3220 		memcpy(&d[z], p->header, p->header_length);
3221 	}
3222 
3223 	pd = d + z - payload_z;
3224 	payload_end_index = payload_index + p->payload_length;
3225 	for (i = 0; i < payload_z; i++) {
3226 		page               = payload_index >> PAGE_SHIFT;
3227 		offset             = payload_index & ~PAGE_MASK;
3228 		next_page_index    = (page + 1) << PAGE_SHIFT;
3229 		length             =
3230 			min(next_page_index, payload_end_index) - payload_index;
3231 		pd[i].req_count    = cpu_to_le16(length);
3232 
3233 		page_bus = page_private(buffer->pages[page]);
3234 		pd[i].data_address = cpu_to_le32(page_bus + offset);
3235 
3236 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3237 						 page_bus, offset, length,
3238 						 DMA_TO_DEVICE);
3239 
3240 		payload_index += length;
3241 	}
3242 
3243 	if (p->interrupt)
3244 		irq = DESCRIPTOR_IRQ_ALWAYS;
3245 	else
3246 		irq = DESCRIPTOR_NO_IRQ;
3247 
3248 	last = z == 2 ? d : d + z - 1;
3249 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3250 				     DESCRIPTOR_STATUS |
3251 				     DESCRIPTOR_BRANCH_ALWAYS |
3252 				     irq);
3253 
3254 	context_append(&ctx->context, d, z, header_z);
3255 
3256 	return 0;
3257 }
3258 
3259 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3260 				       struct fw_iso_packet *packet,
3261 				       struct fw_iso_buffer *buffer,
3262 				       unsigned long payload)
3263 {
3264 	struct device *device = ctx->context.ohci->card.device;
3265 	struct descriptor *d, *pd;
3266 	dma_addr_t d_bus, page_bus;
3267 	u32 z, header_z, rest;
3268 	int i, j, length;
3269 	int page, offset, packet_count, header_size, payload_per_buffer;
3270 
3271 	/*
3272 	 * The OHCI controller puts the isochronous header and trailer in the
3273 	 * buffer, so we need at least 8 bytes.
3274 	 */
3275 	packet_count = packet->header_length / ctx->base.header_size;
3276 	header_size  = max(ctx->base.header_size, (size_t)8);
3277 
3278 	/* Get header size in number of descriptors. */
3279 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3280 	page     = payload >> PAGE_SHIFT;
3281 	offset   = payload & ~PAGE_MASK;
3282 	payload_per_buffer = packet->payload_length / packet_count;
3283 
3284 	for (i = 0; i < packet_count; i++) {
3285 		/* d points to the header descriptor */
3286 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3287 		d = context_get_descriptors(&ctx->context,
3288 				z + header_z, &d_bus);
3289 		if (d == NULL)
3290 			return -ENOMEM;
3291 
3292 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3293 					      DESCRIPTOR_INPUT_MORE);
3294 		if (packet->skip && i == 0)
3295 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3296 		d->req_count    = cpu_to_le16(header_size);
3297 		d->res_count    = d->req_count;
3298 		d->transfer_status = 0;
3299 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3300 
3301 		rest = payload_per_buffer;
3302 		pd = d;
3303 		for (j = 1; j < z; j++) {
3304 			pd++;
3305 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3306 						  DESCRIPTOR_INPUT_MORE);
3307 
3308 			if (offset + rest < PAGE_SIZE)
3309 				length = rest;
3310 			else
3311 				length = PAGE_SIZE - offset;
3312 			pd->req_count = cpu_to_le16(length);
3313 			pd->res_count = pd->req_count;
3314 			pd->transfer_status = 0;
3315 
3316 			page_bus = page_private(buffer->pages[page]);
3317 			pd->data_address = cpu_to_le32(page_bus + offset);
3318 
3319 			dma_sync_single_range_for_device(device, page_bus,
3320 							 offset, length,
3321 							 DMA_FROM_DEVICE);
3322 
3323 			offset = (offset + length) & ~PAGE_MASK;
3324 			rest -= length;
3325 			if (offset == 0)
3326 				page++;
3327 		}
3328 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3329 					  DESCRIPTOR_INPUT_LAST |
3330 					  DESCRIPTOR_BRANCH_ALWAYS);
3331 		if (packet->interrupt && i == packet_count - 1)
3332 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3333 
3334 		context_append(&ctx->context, d, z, header_z);
3335 	}
3336 
3337 	return 0;
3338 }
3339 
3340 static int queue_iso_buffer_fill(struct iso_context *ctx,
3341 				 struct fw_iso_packet *packet,
3342 				 struct fw_iso_buffer *buffer,
3343 				 unsigned long payload)
3344 {
3345 	struct descriptor *d;
3346 	dma_addr_t d_bus, page_bus;
3347 	int page, offset, rest, z, i, length;
3348 
3349 	page   = payload >> PAGE_SHIFT;
3350 	offset = payload & ~PAGE_MASK;
3351 	rest   = packet->payload_length;
3352 
3353 	/* We need one descriptor for each page in the buffer. */
3354 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3355 
3356 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3357 		return -EFAULT;
3358 
3359 	for (i = 0; i < z; i++) {
3360 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3361 		if (d == NULL)
3362 			return -ENOMEM;
3363 
3364 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3365 					 DESCRIPTOR_BRANCH_ALWAYS);
3366 		if (packet->skip && i == 0)
3367 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3368 		if (packet->interrupt && i == z - 1)
3369 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3370 
3371 		if (offset + rest < PAGE_SIZE)
3372 			length = rest;
3373 		else
3374 			length = PAGE_SIZE - offset;
3375 		d->req_count = cpu_to_le16(length);
3376 		d->res_count = d->req_count;
3377 		d->transfer_status = 0;
3378 
3379 		page_bus = page_private(buffer->pages[page]);
3380 		d->data_address = cpu_to_le32(page_bus + offset);
3381 
3382 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3383 						 page_bus, offset, length,
3384 						 DMA_FROM_DEVICE);
3385 
3386 		rest -= length;
3387 		offset = 0;
3388 		page++;
3389 
3390 		context_append(&ctx->context, d, 1, 0);
3391 	}
3392 
3393 	return 0;
3394 }
3395 
3396 static int ohci_queue_iso(struct fw_iso_context *base,
3397 			  struct fw_iso_packet *packet,
3398 			  struct fw_iso_buffer *buffer,
3399 			  unsigned long payload)
3400 {
3401 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3402 	unsigned long flags;
3403 	int ret = -ENOSYS;
3404 
3405 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3406 	switch (base->type) {
3407 	case FW_ISO_CONTEXT_TRANSMIT:
3408 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
3409 		break;
3410 	case FW_ISO_CONTEXT_RECEIVE:
3411 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3412 		break;
3413 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3414 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3415 		break;
3416 	}
3417 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3418 
3419 	return ret;
3420 }
3421 
3422 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3423 {
3424 	struct context *ctx =
3425 			&container_of(base, struct iso_context, base)->context;
3426 
3427 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3428 }
3429 
3430 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3431 {
3432 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3433 	int ret = 0;
3434 
3435 	tasklet_disable(&ctx->context.tasklet);
3436 
3437 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3438 		context_tasklet((unsigned long)&ctx->context);
3439 
3440 		switch (base->type) {
3441 		case FW_ISO_CONTEXT_TRANSMIT:
3442 		case FW_ISO_CONTEXT_RECEIVE:
3443 			if (ctx->header_length != 0)
3444 				flush_iso_completions(ctx);
3445 			break;
3446 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3447 			if (ctx->mc_completed != 0)
3448 				flush_ir_buffer_fill(ctx);
3449 			break;
3450 		default:
3451 			ret = -ENOSYS;
3452 		}
3453 
3454 		clear_bit_unlock(0, &ctx->flushing_completions);
3455 		smp_mb__after_clear_bit();
3456 	}
3457 
3458 	tasklet_enable(&ctx->context.tasklet);
3459 
3460 	return ret;
3461 }
3462 
3463 static const struct fw_card_driver ohci_driver = {
3464 	.enable			= ohci_enable,
3465 	.read_phy_reg		= ohci_read_phy_reg,
3466 	.update_phy_reg		= ohci_update_phy_reg,
3467 	.set_config_rom		= ohci_set_config_rom,
3468 	.send_request		= ohci_send_request,
3469 	.send_response		= ohci_send_response,
3470 	.cancel_packet		= ohci_cancel_packet,
3471 	.enable_phys_dma	= ohci_enable_phys_dma,
3472 	.read_csr		= ohci_read_csr,
3473 	.write_csr		= ohci_write_csr,
3474 
3475 	.allocate_iso_context	= ohci_allocate_iso_context,
3476 	.free_iso_context	= ohci_free_iso_context,
3477 	.set_iso_channels	= ohci_set_iso_channels,
3478 	.queue_iso		= ohci_queue_iso,
3479 	.flush_queue_iso	= ohci_flush_queue_iso,
3480 	.flush_iso_completions	= ohci_flush_iso_completions,
3481 	.start_iso		= ohci_start_iso,
3482 	.stop_iso		= ohci_stop_iso,
3483 };
3484 
3485 #ifdef CONFIG_PPC_PMAC
3486 static void pmac_ohci_on(struct pci_dev *dev)
3487 {
3488 	if (machine_is(powermac)) {
3489 		struct device_node *ofn = pci_device_to_OF_node(dev);
3490 
3491 		if (ofn) {
3492 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3493 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3494 		}
3495 	}
3496 }
3497 
3498 static void pmac_ohci_off(struct pci_dev *dev)
3499 {
3500 	if (machine_is(powermac)) {
3501 		struct device_node *ofn = pci_device_to_OF_node(dev);
3502 
3503 		if (ofn) {
3504 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3505 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3506 		}
3507 	}
3508 }
3509 #else
3510 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3511 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3512 #endif /* CONFIG_PPC_PMAC */
3513 
3514 static int __devinit pci_probe(struct pci_dev *dev,
3515 			       const struct pci_device_id *ent)
3516 {
3517 	struct fw_ohci *ohci;
3518 	u32 bus_options, max_receive, link_speed, version;
3519 	u64 guid;
3520 	int i, err;
3521 	size_t size;
3522 
3523 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3524 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3525 		return -ENOSYS;
3526 	}
3527 
3528 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3529 	if (ohci == NULL) {
3530 		err = -ENOMEM;
3531 		goto fail;
3532 	}
3533 
3534 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3535 
3536 	pmac_ohci_on(dev);
3537 
3538 	err = pci_enable_device(dev);
3539 	if (err) {
3540 		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3541 		goto fail_free;
3542 	}
3543 
3544 	pci_set_master(dev);
3545 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3546 	pci_set_drvdata(dev, ohci);
3547 
3548 	spin_lock_init(&ohci->lock);
3549 	mutex_init(&ohci->phy_reg_mutex);
3550 
3551 	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3552 
3553 	if (!(pci_resource_flags(dev, 0) & IORESOURCE_MEM) ||
3554 	    pci_resource_len(dev, 0) < OHCI1394_REGISTER_SIZE) {
3555 		dev_err(&dev->dev, "invalid MMIO resource\n");
3556 		err = -ENXIO;
3557 		goto fail_disable;
3558 	}
3559 
3560 	err = pci_request_region(dev, 0, ohci_driver_name);
3561 	if (err) {
3562 		dev_err(&dev->dev, "MMIO resource unavailable\n");
3563 		goto fail_disable;
3564 	}
3565 
3566 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3567 	if (ohci->registers == NULL) {
3568 		dev_err(&dev->dev, "failed to remap registers\n");
3569 		err = -ENXIO;
3570 		goto fail_iomem;
3571 	}
3572 
3573 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3574 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3575 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3576 		     ohci_quirks[i].device == dev->device) &&
3577 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3578 		     ohci_quirks[i].revision >= dev->revision)) {
3579 			ohci->quirks = ohci_quirks[i].flags;
3580 			break;
3581 		}
3582 	if (param_quirks)
3583 		ohci->quirks = param_quirks;
3584 
3585 	/*
3586 	 * Because dma_alloc_coherent() allocates at least one page,
3587 	 * we save space by using a common buffer for the AR request/
3588 	 * response descriptors and the self IDs buffer.
3589 	 */
3590 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3591 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3592 	ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3593 					       PAGE_SIZE,
3594 					       &ohci->misc_buffer_bus,
3595 					       GFP_KERNEL);
3596 	if (!ohci->misc_buffer) {
3597 		err = -ENOMEM;
3598 		goto fail_iounmap;
3599 	}
3600 
3601 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3602 			      OHCI1394_AsReqRcvContextControlSet);
3603 	if (err < 0)
3604 		goto fail_misc_buf;
3605 
3606 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3607 			      OHCI1394_AsRspRcvContextControlSet);
3608 	if (err < 0)
3609 		goto fail_arreq_ctx;
3610 
3611 	err = context_init(&ohci->at_request_ctx, ohci,
3612 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3613 	if (err < 0)
3614 		goto fail_arrsp_ctx;
3615 
3616 	err = context_init(&ohci->at_response_ctx, ohci,
3617 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3618 	if (err < 0)
3619 		goto fail_atreq_ctx;
3620 
3621 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3622 	ohci->ir_context_channels = ~0ULL;
3623 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3624 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3625 	ohci->ir_context_mask = ohci->ir_context_support;
3626 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3627 	size = sizeof(struct iso_context) * ohci->n_ir;
3628 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3629 
3630 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3631 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3632 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3633 	ohci->it_context_mask = ohci->it_context_support;
3634 	ohci->n_it = hweight32(ohci->it_context_mask);
3635 	size = sizeof(struct iso_context) * ohci->n_it;
3636 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3637 
3638 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3639 		err = -ENOMEM;
3640 		goto fail_contexts;
3641 	}
3642 
3643 	ohci->self_id_cpu = ohci->misc_buffer     + PAGE_SIZE/2;
3644 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3645 
3646 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3647 	max_receive = (bus_options >> 12) & 0xf;
3648 	link_speed = bus_options & 0x7;
3649 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3650 		reg_read(ohci, OHCI1394_GUIDLo);
3651 
3652 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3653 	if (err)
3654 		goto fail_contexts;
3655 
3656 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3657 	dev_notice(&dev->dev,
3658 		  "added OHCI v%x.%x device as card %d, "
3659 		  "%d IR + %d IT contexts, quirks 0x%x\n",
3660 		  version >> 16, version & 0xff, ohci->card.index,
3661 		  ohci->n_ir, ohci->n_it, ohci->quirks);
3662 
3663 	return 0;
3664 
3665  fail_contexts:
3666 	kfree(ohci->ir_context_list);
3667 	kfree(ohci->it_context_list);
3668 	context_release(&ohci->at_response_ctx);
3669  fail_atreq_ctx:
3670 	context_release(&ohci->at_request_ctx);
3671  fail_arrsp_ctx:
3672 	ar_context_release(&ohci->ar_response_ctx);
3673  fail_arreq_ctx:
3674 	ar_context_release(&ohci->ar_request_ctx);
3675  fail_misc_buf:
3676 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3677 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3678  fail_iounmap:
3679 	pci_iounmap(dev, ohci->registers);
3680  fail_iomem:
3681 	pci_release_region(dev, 0);
3682  fail_disable:
3683 	pci_disable_device(dev);
3684  fail_free:
3685 	kfree(ohci);
3686 	pmac_ohci_off(dev);
3687  fail:
3688 	if (err == -ENOMEM)
3689 		dev_err(&dev->dev, "out of memory\n");
3690 
3691 	return err;
3692 }
3693 
3694 static void pci_remove(struct pci_dev *dev)
3695 {
3696 	struct fw_ohci *ohci;
3697 
3698 	ohci = pci_get_drvdata(dev);
3699 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3700 	flush_writes(ohci);
3701 	cancel_work_sync(&ohci->bus_reset_work);
3702 	fw_core_remove_card(&ohci->card);
3703 
3704 	/*
3705 	 * FIXME: Fail all pending packets here, now that the upper
3706 	 * layers can't queue any more.
3707 	 */
3708 
3709 	software_reset(ohci);
3710 	free_irq(dev->irq, ohci);
3711 
3712 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3713 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3714 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3715 	if (ohci->config_rom)
3716 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3717 				  ohci->config_rom, ohci->config_rom_bus);
3718 	ar_context_release(&ohci->ar_request_ctx);
3719 	ar_context_release(&ohci->ar_response_ctx);
3720 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3721 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3722 	context_release(&ohci->at_request_ctx);
3723 	context_release(&ohci->at_response_ctx);
3724 	kfree(ohci->it_context_list);
3725 	kfree(ohci->ir_context_list);
3726 	pci_disable_msi(dev);
3727 	pci_iounmap(dev, ohci->registers);
3728 	pci_release_region(dev, 0);
3729 	pci_disable_device(dev);
3730 	kfree(ohci);
3731 	pmac_ohci_off(dev);
3732 
3733 	dev_notice(&dev->dev, "removed fw-ohci device\n");
3734 }
3735 
3736 #ifdef CONFIG_PM
3737 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3738 {
3739 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3740 	int err;
3741 
3742 	software_reset(ohci);
3743 	free_irq(dev->irq, ohci);
3744 	pci_disable_msi(dev);
3745 	err = pci_save_state(dev);
3746 	if (err) {
3747 		dev_err(&dev->dev, "pci_save_state failed\n");
3748 		return err;
3749 	}
3750 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3751 	if (err)
3752 		dev_err(&dev->dev, "pci_set_power_state failed with %d\n", err);
3753 	pmac_ohci_off(dev);
3754 
3755 	return 0;
3756 }
3757 
3758 static int pci_resume(struct pci_dev *dev)
3759 {
3760 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3761 	int err;
3762 
3763 	pmac_ohci_on(dev);
3764 	pci_set_power_state(dev, PCI_D0);
3765 	pci_restore_state(dev);
3766 	err = pci_enable_device(dev);
3767 	if (err) {
3768 		dev_err(&dev->dev, "pci_enable_device failed\n");
3769 		return err;
3770 	}
3771 
3772 	/* Some systems don't setup GUID register on resume from ram  */
3773 	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3774 					!reg_read(ohci, OHCI1394_GUIDHi)) {
3775 		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3776 		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3777 	}
3778 
3779 	err = ohci_enable(&ohci->card, NULL, 0);
3780 	if (err)
3781 		return err;
3782 
3783 	ohci_resume_iso_dma(ohci);
3784 
3785 	return 0;
3786 }
3787 #endif
3788 
3789 static const struct pci_device_id pci_table[] = {
3790 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3791 	{ }
3792 };
3793 
3794 MODULE_DEVICE_TABLE(pci, pci_table);
3795 
3796 static struct pci_driver fw_ohci_pci_driver = {
3797 	.name		= ohci_driver_name,
3798 	.id_table	= pci_table,
3799 	.probe		= pci_probe,
3800 	.remove		= pci_remove,
3801 #ifdef CONFIG_PM
3802 	.resume		= pci_resume,
3803 	.suspend	= pci_suspend,
3804 #endif
3805 };
3806 
3807 module_pci_driver(fw_ohci_pci_driver);
3808 
3809 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3810 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3811 MODULE_LICENSE("GPL");
3812 
3813 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3814 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3815 MODULE_ALIAS("ohci1394");
3816 #endif
3817