xref: /openbmc/linux/drivers/firewire/ohci.c (revision 8fdff1dc)
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 asynchronous 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 static int initiated_reset(struct fw_ohci *ohci)
1781 {
1782 	int reg;
1783 	int ret = 0;
1784 
1785 	mutex_lock(&ohci->phy_reg_mutex);
1786 	reg = write_phy_reg(ohci, 7, 0xe0); /* Select page 7 */
1787 	if (reg >= 0) {
1788 		reg = read_phy_reg(ohci, 8);
1789 		reg |= 0x40;
1790 		reg = write_phy_reg(ohci, 8, reg); /* set PMODE bit */
1791 		if (reg >= 0) {
1792 			reg = read_phy_reg(ohci, 12); /* read register 12 */
1793 			if (reg >= 0) {
1794 				if ((reg & 0x08) == 0x08) {
1795 					/* bit 3 indicates "initiated reset" */
1796 					ret = 0x2;
1797 				}
1798 			}
1799 		}
1800 	}
1801 	mutex_unlock(&ohci->phy_reg_mutex);
1802 	return ret;
1803 }
1804 
1805 /*
1806  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1807  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1808  * Construct the selfID from phy register contents.
1809  */
1810 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
1811 {
1812 	int reg, i, pos, status;
1813 	/* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
1814 	u32 self_id = 0x8040c800;
1815 
1816 	reg = reg_read(ohci, OHCI1394_NodeID);
1817 	if (!(reg & OHCI1394_NodeID_idValid)) {
1818 		dev_notice(ohci->card.device,
1819 			   "node ID not valid, new bus reset in progress\n");
1820 		return -EBUSY;
1821 	}
1822 	self_id |= ((reg & 0x3f) << 24); /* phy ID */
1823 
1824 	reg = ohci_read_phy_reg(&ohci->card, 4);
1825 	if (reg < 0)
1826 		return reg;
1827 	self_id |= ((reg & 0x07) << 8); /* power class */
1828 
1829 	reg = ohci_read_phy_reg(&ohci->card, 1);
1830 	if (reg < 0)
1831 		return reg;
1832 	self_id |= ((reg & 0x3f) << 16); /* gap count */
1833 
1834 	for (i = 0; i < 3; i++) {
1835 		status = get_status_for_port(ohci, i);
1836 		if (status < 0)
1837 			return status;
1838 		self_id |= ((status & 0x3) << (6 - (i * 2)));
1839 	}
1840 
1841 	self_id |= initiated_reset(ohci);
1842 
1843 	pos = get_self_id_pos(ohci, self_id, self_id_count);
1844 	if (pos >= 0) {
1845 		memmove(&(ohci->self_id_buffer[pos+1]),
1846 			&(ohci->self_id_buffer[pos]),
1847 			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
1848 		ohci->self_id_buffer[pos] = self_id;
1849 		self_id_count++;
1850 	}
1851 	return self_id_count;
1852 }
1853 
1854 static void bus_reset_work(struct work_struct *work)
1855 {
1856 	struct fw_ohci *ohci =
1857 		container_of(work, struct fw_ohci, bus_reset_work);
1858 	int self_id_count, generation, new_generation, i, j;
1859 	u32 reg;
1860 	void *free_rom = NULL;
1861 	dma_addr_t free_rom_bus = 0;
1862 	bool is_new_root;
1863 
1864 	reg = reg_read(ohci, OHCI1394_NodeID);
1865 	if (!(reg & OHCI1394_NodeID_idValid)) {
1866 		dev_notice(ohci->card.device,
1867 			   "node ID not valid, new bus reset in progress\n");
1868 		return;
1869 	}
1870 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1871 		dev_notice(ohci->card.device, "malconfigured bus\n");
1872 		return;
1873 	}
1874 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1875 			       OHCI1394_NodeID_nodeNumber);
1876 
1877 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1878 	if (!(ohci->is_root && is_new_root))
1879 		reg_write(ohci, OHCI1394_LinkControlSet,
1880 			  OHCI1394_LinkControl_cycleMaster);
1881 	ohci->is_root = is_new_root;
1882 
1883 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1884 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1885 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1886 		return;
1887 	}
1888 	/*
1889 	 * The count in the SelfIDCount register is the number of
1890 	 * bytes in the self ID receive buffer.  Since we also receive
1891 	 * the inverted quadlets and a header quadlet, we shift one
1892 	 * bit extra to get the actual number of self IDs.
1893 	 */
1894 	self_id_count = (reg >> 3) & 0xff;
1895 
1896 	if (self_id_count > 252) {
1897 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1898 		return;
1899 	}
1900 
1901 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1902 	rmb();
1903 
1904 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1905 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1906 			/*
1907 			 * If the invalid data looks like a cycle start packet,
1908 			 * it's likely to be the result of the cycle master
1909 			 * having a wrong gap count.  In this case, the self IDs
1910 			 * so far are valid and should be processed so that the
1911 			 * bus manager can then correct the gap count.
1912 			 */
1913 			if (cond_le32_to_cpu(ohci->self_id_cpu[i])
1914 							== 0xffff008f) {
1915 				dev_notice(ohci->card.device,
1916 					   "ignoring spurious self IDs\n");
1917 				self_id_count = j;
1918 				break;
1919 			} else {
1920 				dev_notice(ohci->card.device,
1921 					   "inconsistent self IDs\n");
1922 				return;
1923 			}
1924 		}
1925 		ohci->self_id_buffer[j] =
1926 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1927 	}
1928 
1929 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
1930 		self_id_count = find_and_insert_self_id(ohci, self_id_count);
1931 		if (self_id_count < 0) {
1932 			dev_notice(ohci->card.device,
1933 				   "could not construct local self ID\n");
1934 			return;
1935 		}
1936 	}
1937 
1938 	if (self_id_count == 0) {
1939 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1940 		return;
1941 	}
1942 	rmb();
1943 
1944 	/*
1945 	 * Check the consistency of the self IDs we just read.  The
1946 	 * problem we face is that a new bus reset can start while we
1947 	 * read out the self IDs from the DMA buffer. If this happens,
1948 	 * the DMA buffer will be overwritten with new self IDs and we
1949 	 * will read out inconsistent data.  The OHCI specification
1950 	 * (section 11.2) recommends a technique similar to
1951 	 * linux/seqlock.h, where we remember the generation of the
1952 	 * self IDs in the buffer before reading them out and compare
1953 	 * it to the current generation after reading them out.  If
1954 	 * the two generations match we know we have a consistent set
1955 	 * of self IDs.
1956 	 */
1957 
1958 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1959 	if (new_generation != generation) {
1960 		dev_notice(ohci->card.device,
1961 			   "new bus reset, discarding self ids\n");
1962 		return;
1963 	}
1964 
1965 	/* FIXME: Document how the locking works. */
1966 	spin_lock_irq(&ohci->lock);
1967 
1968 	ohci->generation = -1; /* prevent AT packet queueing */
1969 	context_stop(&ohci->at_request_ctx);
1970 	context_stop(&ohci->at_response_ctx);
1971 
1972 	spin_unlock_irq(&ohci->lock);
1973 
1974 	/*
1975 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
1976 	 * packets in the AT queues and software needs to drain them.
1977 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
1978 	 */
1979 	at_context_flush(&ohci->at_request_ctx);
1980 	at_context_flush(&ohci->at_response_ctx);
1981 
1982 	spin_lock_irq(&ohci->lock);
1983 
1984 	ohci->generation = generation;
1985 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1986 
1987 	if (ohci->quirks & QUIRK_RESET_PACKET)
1988 		ohci->request_generation = generation;
1989 
1990 	/*
1991 	 * This next bit is unrelated to the AT context stuff but we
1992 	 * have to do it under the spinlock also.  If a new config rom
1993 	 * was set up before this reset, the old one is now no longer
1994 	 * in use and we can free it. Update the config rom pointers
1995 	 * to point to the current config rom and clear the
1996 	 * next_config_rom pointer so a new update can take place.
1997 	 */
1998 
1999 	if (ohci->next_config_rom != NULL) {
2000 		if (ohci->next_config_rom != ohci->config_rom) {
2001 			free_rom      = ohci->config_rom;
2002 			free_rom_bus  = ohci->config_rom_bus;
2003 		}
2004 		ohci->config_rom      = ohci->next_config_rom;
2005 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
2006 		ohci->next_config_rom = NULL;
2007 
2008 		/*
2009 		 * Restore config_rom image and manually update
2010 		 * config_rom registers.  Writing the header quadlet
2011 		 * will indicate that the config rom is ready, so we
2012 		 * do that last.
2013 		 */
2014 		reg_write(ohci, OHCI1394_BusOptions,
2015 			  be32_to_cpu(ohci->config_rom[2]));
2016 		ohci->config_rom[0] = ohci->next_header;
2017 		reg_write(ohci, OHCI1394_ConfigROMhdr,
2018 			  be32_to_cpu(ohci->next_header));
2019 	}
2020 
2021 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2022 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
2023 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
2024 #endif
2025 
2026 	spin_unlock_irq(&ohci->lock);
2027 
2028 	if (free_rom)
2029 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2030 				  free_rom, free_rom_bus);
2031 
2032 	log_selfids(ohci, generation, self_id_count);
2033 
2034 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2035 				 self_id_count, ohci->self_id_buffer,
2036 				 ohci->csr_state_setclear_abdicate);
2037 	ohci->csr_state_setclear_abdicate = false;
2038 }
2039 
2040 static irqreturn_t irq_handler(int irq, void *data)
2041 {
2042 	struct fw_ohci *ohci = data;
2043 	u32 event, iso_event;
2044 	int i;
2045 
2046 	event = reg_read(ohci, OHCI1394_IntEventClear);
2047 
2048 	if (!event || !~event)
2049 		return IRQ_NONE;
2050 
2051 	/*
2052 	 * busReset and postedWriteErr must not be cleared yet
2053 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2054 	 */
2055 	reg_write(ohci, OHCI1394_IntEventClear,
2056 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2057 	log_irqs(ohci, event);
2058 
2059 	if (event & OHCI1394_selfIDComplete)
2060 		queue_work(fw_workqueue, &ohci->bus_reset_work);
2061 
2062 	if (event & OHCI1394_RQPkt)
2063 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2064 
2065 	if (event & OHCI1394_RSPkt)
2066 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2067 
2068 	if (event & OHCI1394_reqTxComplete)
2069 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
2070 
2071 	if (event & OHCI1394_respTxComplete)
2072 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
2073 
2074 	if (event & OHCI1394_isochRx) {
2075 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2076 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2077 
2078 		while (iso_event) {
2079 			i = ffs(iso_event) - 1;
2080 			tasklet_schedule(
2081 				&ohci->ir_context_list[i].context.tasklet);
2082 			iso_event &= ~(1 << i);
2083 		}
2084 	}
2085 
2086 	if (event & OHCI1394_isochTx) {
2087 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2088 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2089 
2090 		while (iso_event) {
2091 			i = ffs(iso_event) - 1;
2092 			tasklet_schedule(
2093 				&ohci->it_context_list[i].context.tasklet);
2094 			iso_event &= ~(1 << i);
2095 		}
2096 	}
2097 
2098 	if (unlikely(event & OHCI1394_regAccessFail))
2099 		dev_err(ohci->card.device, "register access failure\n");
2100 
2101 	if (unlikely(event & OHCI1394_postedWriteErr)) {
2102 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2103 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2104 		reg_write(ohci, OHCI1394_IntEventClear,
2105 			  OHCI1394_postedWriteErr);
2106 		if (printk_ratelimit())
2107 			dev_err(ohci->card.device, "PCI posted write error\n");
2108 	}
2109 
2110 	if (unlikely(event & OHCI1394_cycleTooLong)) {
2111 		if (printk_ratelimit())
2112 			dev_notice(ohci->card.device,
2113 				   "isochronous cycle too long\n");
2114 		reg_write(ohci, OHCI1394_LinkControlSet,
2115 			  OHCI1394_LinkControl_cycleMaster);
2116 	}
2117 
2118 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
2119 		/*
2120 		 * We need to clear this event bit in order to make
2121 		 * cycleMatch isochronous I/O work.  In theory we should
2122 		 * stop active cycleMatch iso contexts now and restart
2123 		 * them at least two cycles later.  (FIXME?)
2124 		 */
2125 		if (printk_ratelimit())
2126 			dev_notice(ohci->card.device,
2127 				   "isochronous cycle inconsistent\n");
2128 	}
2129 
2130 	if (unlikely(event & OHCI1394_unrecoverableError))
2131 		handle_dead_contexts(ohci);
2132 
2133 	if (event & OHCI1394_cycle64Seconds) {
2134 		spin_lock(&ohci->lock);
2135 		update_bus_time(ohci);
2136 		spin_unlock(&ohci->lock);
2137 	} else
2138 		flush_writes(ohci);
2139 
2140 	return IRQ_HANDLED;
2141 }
2142 
2143 static int software_reset(struct fw_ohci *ohci)
2144 {
2145 	u32 val;
2146 	int i;
2147 
2148 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2149 	for (i = 0; i < 500; i++) {
2150 		val = reg_read(ohci, OHCI1394_HCControlSet);
2151 		if (!~val)
2152 			return -ENODEV; /* Card was ejected. */
2153 
2154 		if (!(val & OHCI1394_HCControl_softReset))
2155 			return 0;
2156 
2157 		msleep(1);
2158 	}
2159 
2160 	return -EBUSY;
2161 }
2162 
2163 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2164 {
2165 	size_t size = length * 4;
2166 
2167 	memcpy(dest, src, size);
2168 	if (size < CONFIG_ROM_SIZE)
2169 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2170 }
2171 
2172 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2173 {
2174 	bool enable_1394a;
2175 	int ret, clear, set, offset;
2176 
2177 	/* Check if the driver should configure link and PHY. */
2178 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2179 	      OHCI1394_HCControl_programPhyEnable))
2180 		return 0;
2181 
2182 	/* Paranoia: check whether the PHY supports 1394a, too. */
2183 	enable_1394a = false;
2184 	ret = read_phy_reg(ohci, 2);
2185 	if (ret < 0)
2186 		return ret;
2187 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2188 		ret = read_paged_phy_reg(ohci, 1, 8);
2189 		if (ret < 0)
2190 			return ret;
2191 		if (ret >= 1)
2192 			enable_1394a = true;
2193 	}
2194 
2195 	if (ohci->quirks & QUIRK_NO_1394A)
2196 		enable_1394a = false;
2197 
2198 	/* Configure PHY and link consistently. */
2199 	if (enable_1394a) {
2200 		clear = 0;
2201 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2202 	} else {
2203 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2204 		set = 0;
2205 	}
2206 	ret = update_phy_reg(ohci, 5, clear, set);
2207 	if (ret < 0)
2208 		return ret;
2209 
2210 	if (enable_1394a)
2211 		offset = OHCI1394_HCControlSet;
2212 	else
2213 		offset = OHCI1394_HCControlClear;
2214 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2215 
2216 	/* Clean up: configuration has been taken care of. */
2217 	reg_write(ohci, OHCI1394_HCControlClear,
2218 		  OHCI1394_HCControl_programPhyEnable);
2219 
2220 	return 0;
2221 }
2222 
2223 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2224 {
2225 	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2226 	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2227 	int reg, i;
2228 
2229 	reg = read_phy_reg(ohci, 2);
2230 	if (reg < 0)
2231 		return reg;
2232 	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2233 		return 0;
2234 
2235 	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2236 		reg = read_paged_phy_reg(ohci, 1, i + 10);
2237 		if (reg < 0)
2238 			return reg;
2239 		if (reg != id[i])
2240 			return 0;
2241 	}
2242 	return 1;
2243 }
2244 
2245 static int ohci_enable(struct fw_card *card,
2246 		       const __be32 *config_rom, size_t length)
2247 {
2248 	struct fw_ohci *ohci = fw_ohci(card);
2249 	struct pci_dev *dev = to_pci_dev(card->device);
2250 	u32 lps, version, irqs;
2251 	int i, ret;
2252 
2253 	if (software_reset(ohci)) {
2254 		dev_err(card->device, "failed to reset ohci card\n");
2255 		return -EBUSY;
2256 	}
2257 
2258 	/*
2259 	 * Now enable LPS, which we need in order to start accessing
2260 	 * most of the registers.  In fact, on some cards (ALI M5251),
2261 	 * accessing registers in the SClk domain without LPS enabled
2262 	 * will lock up the machine.  Wait 50msec to make sure we have
2263 	 * full link enabled.  However, with some cards (well, at least
2264 	 * a JMicron PCIe card), we have to try again sometimes.
2265 	 */
2266 	reg_write(ohci, OHCI1394_HCControlSet,
2267 		  OHCI1394_HCControl_LPS |
2268 		  OHCI1394_HCControl_postedWriteEnable);
2269 	flush_writes(ohci);
2270 
2271 	for (lps = 0, i = 0; !lps && i < 3; i++) {
2272 		msleep(50);
2273 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2274 		      OHCI1394_HCControl_LPS;
2275 	}
2276 
2277 	if (!lps) {
2278 		dev_err(card->device, "failed to set Link Power Status\n");
2279 		return -EIO;
2280 	}
2281 
2282 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2283 		ret = probe_tsb41ba3d(ohci);
2284 		if (ret < 0)
2285 			return ret;
2286 		if (ret)
2287 			dev_notice(card->device, "local TSB41BA3D phy\n");
2288 		else
2289 			ohci->quirks &= ~QUIRK_TI_SLLZ059;
2290 	}
2291 
2292 	reg_write(ohci, OHCI1394_HCControlClear,
2293 		  OHCI1394_HCControl_noByteSwapData);
2294 
2295 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2296 	reg_write(ohci, OHCI1394_LinkControlSet,
2297 		  OHCI1394_LinkControl_cycleTimerEnable |
2298 		  OHCI1394_LinkControl_cycleMaster);
2299 
2300 	reg_write(ohci, OHCI1394_ATRetries,
2301 		  OHCI1394_MAX_AT_REQ_RETRIES |
2302 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2303 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2304 		  (200 << 16));
2305 
2306 	ohci->bus_time_running = false;
2307 
2308 	for (i = 0; i < 32; i++)
2309 		if (ohci->ir_context_support & (1 << i))
2310 			reg_write(ohci, OHCI1394_IsoRcvContextControlClear(i),
2311 				  IR_CONTEXT_MULTI_CHANNEL_MODE);
2312 
2313 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2314 	if (version >= OHCI_VERSION_1_1) {
2315 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2316 			  0xfffffffe);
2317 		card->broadcast_channel_auto_allocated = true;
2318 	}
2319 
2320 	/* Get implemented bits of the priority arbitration request counter. */
2321 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2322 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2323 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2324 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2325 
2326 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
2327 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2328 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2329 
2330 	ret = configure_1394a_enhancements(ohci);
2331 	if (ret < 0)
2332 		return ret;
2333 
2334 	/* Activate link_on bit and contender bit in our self ID packets.*/
2335 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2336 	if (ret < 0)
2337 		return ret;
2338 
2339 	/*
2340 	 * When the link is not yet enabled, the atomic config rom
2341 	 * update mechanism described below in ohci_set_config_rom()
2342 	 * is not active.  We have to update ConfigRomHeader and
2343 	 * BusOptions manually, and the write to ConfigROMmap takes
2344 	 * effect immediately.  We tie this to the enabling of the
2345 	 * link, so we have a valid config rom before enabling - the
2346 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2347 	 * values before enabling.
2348 	 *
2349 	 * However, when the ConfigROMmap is written, some controllers
2350 	 * always read back quadlets 0 and 2 from the config rom to
2351 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2352 	 * They shouldn't do that in this initial case where the link
2353 	 * isn't enabled.  This means we have to use the same
2354 	 * workaround here, setting the bus header to 0 and then write
2355 	 * the right values in the bus reset tasklet.
2356 	 */
2357 
2358 	if (config_rom) {
2359 		ohci->next_config_rom =
2360 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2361 					   &ohci->next_config_rom_bus,
2362 					   GFP_KERNEL);
2363 		if (ohci->next_config_rom == NULL)
2364 			return -ENOMEM;
2365 
2366 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2367 	} else {
2368 		/*
2369 		 * In the suspend case, config_rom is NULL, which
2370 		 * means that we just reuse the old config rom.
2371 		 */
2372 		ohci->next_config_rom = ohci->config_rom;
2373 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2374 	}
2375 
2376 	ohci->next_header = ohci->next_config_rom[0];
2377 	ohci->next_config_rom[0] = 0;
2378 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2379 	reg_write(ohci, OHCI1394_BusOptions,
2380 		  be32_to_cpu(ohci->next_config_rom[2]));
2381 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2382 
2383 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2384 
2385 	if (!(ohci->quirks & QUIRK_NO_MSI))
2386 		pci_enable_msi(dev);
2387 	if (request_irq(dev->irq, irq_handler,
2388 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
2389 			ohci_driver_name, ohci)) {
2390 		dev_err(card->device, "failed to allocate interrupt %d\n",
2391 			dev->irq);
2392 		pci_disable_msi(dev);
2393 
2394 		if (config_rom) {
2395 			dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2396 					  ohci->next_config_rom,
2397 					  ohci->next_config_rom_bus);
2398 			ohci->next_config_rom = NULL;
2399 		}
2400 		return -EIO;
2401 	}
2402 
2403 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2404 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2405 		OHCI1394_isochTx | OHCI1394_isochRx |
2406 		OHCI1394_postedWriteErr |
2407 		OHCI1394_selfIDComplete |
2408 		OHCI1394_regAccessFail |
2409 		OHCI1394_cycleInconsistent |
2410 		OHCI1394_unrecoverableError |
2411 		OHCI1394_cycleTooLong |
2412 		OHCI1394_masterIntEnable;
2413 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2414 		irqs |= OHCI1394_busReset;
2415 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2416 
2417 	reg_write(ohci, OHCI1394_HCControlSet,
2418 		  OHCI1394_HCControl_linkEnable |
2419 		  OHCI1394_HCControl_BIBimageValid);
2420 
2421 	reg_write(ohci, OHCI1394_LinkControlSet,
2422 		  OHCI1394_LinkControl_rcvSelfID |
2423 		  OHCI1394_LinkControl_rcvPhyPkt);
2424 
2425 	ar_context_run(&ohci->ar_request_ctx);
2426 	ar_context_run(&ohci->ar_response_ctx);
2427 
2428 	flush_writes(ohci);
2429 
2430 	/* We are ready to go, reset bus to finish initialization. */
2431 	fw_schedule_bus_reset(&ohci->card, false, true);
2432 
2433 	return 0;
2434 }
2435 
2436 static int ohci_set_config_rom(struct fw_card *card,
2437 			       const __be32 *config_rom, size_t length)
2438 {
2439 	struct fw_ohci *ohci;
2440 	__be32 *next_config_rom;
2441 	dma_addr_t uninitialized_var(next_config_rom_bus);
2442 
2443 	ohci = fw_ohci(card);
2444 
2445 	/*
2446 	 * When the OHCI controller is enabled, the config rom update
2447 	 * mechanism is a bit tricky, but easy enough to use.  See
2448 	 * section 5.5.6 in the OHCI specification.
2449 	 *
2450 	 * The OHCI controller caches the new config rom address in a
2451 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2452 	 * for the changes to take place.  When the bus reset is
2453 	 * detected, the controller loads the new values for the
2454 	 * ConfigRomHeader and BusOptions registers from the specified
2455 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2456 	 * shadow register. All automatically and atomically.
2457 	 *
2458 	 * Now, there's a twist to this story.  The automatic load of
2459 	 * ConfigRomHeader and BusOptions doesn't honor the
2460 	 * noByteSwapData bit, so with a be32 config rom, the
2461 	 * controller will load be32 values in to these registers
2462 	 * during the atomic update, even on litte endian
2463 	 * architectures.  The workaround we use is to put a 0 in the
2464 	 * header quadlet; 0 is endian agnostic and means that the
2465 	 * config rom isn't ready yet.  In the bus reset tasklet we
2466 	 * then set up the real values for the two registers.
2467 	 *
2468 	 * We use ohci->lock to avoid racing with the code that sets
2469 	 * ohci->next_config_rom to NULL (see bus_reset_work).
2470 	 */
2471 
2472 	next_config_rom =
2473 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2474 				   &next_config_rom_bus, GFP_KERNEL);
2475 	if (next_config_rom == NULL)
2476 		return -ENOMEM;
2477 
2478 	spin_lock_irq(&ohci->lock);
2479 
2480 	/*
2481 	 * If there is not an already pending config_rom update,
2482 	 * push our new allocation into the ohci->next_config_rom
2483 	 * and then mark the local variable as null so that we
2484 	 * won't deallocate the new buffer.
2485 	 *
2486 	 * OTOH, if there is a pending config_rom update, just
2487 	 * use that buffer with the new config_rom data, and
2488 	 * let this routine free the unused DMA allocation.
2489 	 */
2490 
2491 	if (ohci->next_config_rom == NULL) {
2492 		ohci->next_config_rom = next_config_rom;
2493 		ohci->next_config_rom_bus = next_config_rom_bus;
2494 		next_config_rom = NULL;
2495 	}
2496 
2497 	copy_config_rom(ohci->next_config_rom, config_rom, length);
2498 
2499 	ohci->next_header = config_rom[0];
2500 	ohci->next_config_rom[0] = 0;
2501 
2502 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2503 
2504 	spin_unlock_irq(&ohci->lock);
2505 
2506 	/* If we didn't use the DMA allocation, delete it. */
2507 	if (next_config_rom != NULL)
2508 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2509 				  next_config_rom, next_config_rom_bus);
2510 
2511 	/*
2512 	 * Now initiate a bus reset to have the changes take
2513 	 * effect. We clean up the old config rom memory and DMA
2514 	 * mappings in the bus reset tasklet, since the OHCI
2515 	 * controller could need to access it before the bus reset
2516 	 * takes effect.
2517 	 */
2518 
2519 	fw_schedule_bus_reset(&ohci->card, true, true);
2520 
2521 	return 0;
2522 }
2523 
2524 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2525 {
2526 	struct fw_ohci *ohci = fw_ohci(card);
2527 
2528 	at_context_transmit(&ohci->at_request_ctx, packet);
2529 }
2530 
2531 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2532 {
2533 	struct fw_ohci *ohci = fw_ohci(card);
2534 
2535 	at_context_transmit(&ohci->at_response_ctx, packet);
2536 }
2537 
2538 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2539 {
2540 	struct fw_ohci *ohci = fw_ohci(card);
2541 	struct context *ctx = &ohci->at_request_ctx;
2542 	struct driver_data *driver_data = packet->driver_data;
2543 	int ret = -ENOENT;
2544 
2545 	tasklet_disable(&ctx->tasklet);
2546 
2547 	if (packet->ack != 0)
2548 		goto out;
2549 
2550 	if (packet->payload_mapped)
2551 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2552 				 packet->payload_length, DMA_TO_DEVICE);
2553 
2554 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2555 	driver_data->packet = NULL;
2556 	packet->ack = RCODE_CANCELLED;
2557 	packet->callback(packet, &ohci->card, packet->ack);
2558 	ret = 0;
2559  out:
2560 	tasklet_enable(&ctx->tasklet);
2561 
2562 	return ret;
2563 }
2564 
2565 static int ohci_enable_phys_dma(struct fw_card *card,
2566 				int node_id, int generation)
2567 {
2568 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2569 	return 0;
2570 #else
2571 	struct fw_ohci *ohci = fw_ohci(card);
2572 	unsigned long flags;
2573 	int n, ret = 0;
2574 
2575 	/*
2576 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2577 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2578 	 */
2579 
2580 	spin_lock_irqsave(&ohci->lock, flags);
2581 
2582 	if (ohci->generation != generation) {
2583 		ret = -ESTALE;
2584 		goto out;
2585 	}
2586 
2587 	/*
2588 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2589 	 * enabled for _all_ nodes on remote buses.
2590 	 */
2591 
2592 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2593 	if (n < 32)
2594 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2595 	else
2596 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2597 
2598 	flush_writes(ohci);
2599  out:
2600 	spin_unlock_irqrestore(&ohci->lock, flags);
2601 
2602 	return ret;
2603 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2604 }
2605 
2606 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2607 {
2608 	struct fw_ohci *ohci = fw_ohci(card);
2609 	unsigned long flags;
2610 	u32 value;
2611 
2612 	switch (csr_offset) {
2613 	case CSR_STATE_CLEAR:
2614 	case CSR_STATE_SET:
2615 		if (ohci->is_root &&
2616 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2617 		     OHCI1394_LinkControl_cycleMaster))
2618 			value = CSR_STATE_BIT_CMSTR;
2619 		else
2620 			value = 0;
2621 		if (ohci->csr_state_setclear_abdicate)
2622 			value |= CSR_STATE_BIT_ABDICATE;
2623 
2624 		return value;
2625 
2626 	case CSR_NODE_IDS:
2627 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2628 
2629 	case CSR_CYCLE_TIME:
2630 		return get_cycle_time(ohci);
2631 
2632 	case CSR_BUS_TIME:
2633 		/*
2634 		 * We might be called just after the cycle timer has wrapped
2635 		 * around but just before the cycle64Seconds handler, so we
2636 		 * better check here, too, if the bus time needs to be updated.
2637 		 */
2638 		spin_lock_irqsave(&ohci->lock, flags);
2639 		value = update_bus_time(ohci);
2640 		spin_unlock_irqrestore(&ohci->lock, flags);
2641 		return value;
2642 
2643 	case CSR_BUSY_TIMEOUT:
2644 		value = reg_read(ohci, OHCI1394_ATRetries);
2645 		return (value >> 4) & 0x0ffff00f;
2646 
2647 	case CSR_PRIORITY_BUDGET:
2648 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2649 			(ohci->pri_req_max << 8);
2650 
2651 	default:
2652 		WARN_ON(1);
2653 		return 0;
2654 	}
2655 }
2656 
2657 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2658 {
2659 	struct fw_ohci *ohci = fw_ohci(card);
2660 	unsigned long flags;
2661 
2662 	switch (csr_offset) {
2663 	case CSR_STATE_CLEAR:
2664 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2665 			reg_write(ohci, OHCI1394_LinkControlClear,
2666 				  OHCI1394_LinkControl_cycleMaster);
2667 			flush_writes(ohci);
2668 		}
2669 		if (value & CSR_STATE_BIT_ABDICATE)
2670 			ohci->csr_state_setclear_abdicate = false;
2671 		break;
2672 
2673 	case CSR_STATE_SET:
2674 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2675 			reg_write(ohci, OHCI1394_LinkControlSet,
2676 				  OHCI1394_LinkControl_cycleMaster);
2677 			flush_writes(ohci);
2678 		}
2679 		if (value & CSR_STATE_BIT_ABDICATE)
2680 			ohci->csr_state_setclear_abdicate = true;
2681 		break;
2682 
2683 	case CSR_NODE_IDS:
2684 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2685 		flush_writes(ohci);
2686 		break;
2687 
2688 	case CSR_CYCLE_TIME:
2689 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2690 		reg_write(ohci, OHCI1394_IntEventSet,
2691 			  OHCI1394_cycleInconsistent);
2692 		flush_writes(ohci);
2693 		break;
2694 
2695 	case CSR_BUS_TIME:
2696 		spin_lock_irqsave(&ohci->lock, flags);
2697 		ohci->bus_time = (update_bus_time(ohci) & 0x40) |
2698 		                 (value & ~0x7f);
2699 		spin_unlock_irqrestore(&ohci->lock, flags);
2700 		break;
2701 
2702 	case CSR_BUSY_TIMEOUT:
2703 		value = (value & 0xf) | ((value & 0xf) << 4) |
2704 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2705 		reg_write(ohci, OHCI1394_ATRetries, value);
2706 		flush_writes(ohci);
2707 		break;
2708 
2709 	case CSR_PRIORITY_BUDGET:
2710 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2711 		flush_writes(ohci);
2712 		break;
2713 
2714 	default:
2715 		WARN_ON(1);
2716 		break;
2717 	}
2718 }
2719 
2720 static void flush_iso_completions(struct iso_context *ctx)
2721 {
2722 	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2723 			      ctx->header_length, ctx->header,
2724 			      ctx->base.callback_data);
2725 	ctx->header_length = 0;
2726 }
2727 
2728 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2729 {
2730 	u32 *ctx_hdr;
2731 
2732 	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE)
2733 		flush_iso_completions(ctx);
2734 
2735 	ctx_hdr = ctx->header + ctx->header_length;
2736 	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2737 
2738 	/*
2739 	 * The two iso header quadlets are byteswapped to little
2740 	 * endian by the controller, but we want to present them
2741 	 * as big endian for consistency with the bus endianness.
2742 	 */
2743 	if (ctx->base.header_size > 0)
2744 		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2745 	if (ctx->base.header_size > 4)
2746 		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2747 	if (ctx->base.header_size > 8)
2748 		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2749 	ctx->header_length += ctx->base.header_size;
2750 }
2751 
2752 static int handle_ir_packet_per_buffer(struct context *context,
2753 				       struct descriptor *d,
2754 				       struct descriptor *last)
2755 {
2756 	struct iso_context *ctx =
2757 		container_of(context, struct iso_context, context);
2758 	struct descriptor *pd;
2759 	u32 buffer_dma;
2760 
2761 	for (pd = d; pd <= last; pd++)
2762 		if (pd->transfer_status)
2763 			break;
2764 	if (pd > last)
2765 		/* Descriptor(s) not done yet, stop iteration */
2766 		return 0;
2767 
2768 	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2769 		d++;
2770 		buffer_dma = le32_to_cpu(d->data_address);
2771 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2772 					      buffer_dma & PAGE_MASK,
2773 					      buffer_dma & ~PAGE_MASK,
2774 					      le16_to_cpu(d->req_count),
2775 					      DMA_FROM_DEVICE);
2776 	}
2777 
2778 	copy_iso_headers(ctx, (u32 *) (last + 1));
2779 
2780 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2781 		flush_iso_completions(ctx);
2782 
2783 	return 1;
2784 }
2785 
2786 /* d == last because each descriptor block is only a single descriptor. */
2787 static int handle_ir_buffer_fill(struct context *context,
2788 				 struct descriptor *d,
2789 				 struct descriptor *last)
2790 {
2791 	struct iso_context *ctx =
2792 		container_of(context, struct iso_context, context);
2793 	unsigned int req_count, res_count, completed;
2794 	u32 buffer_dma;
2795 
2796 	req_count = le16_to_cpu(last->req_count);
2797 	res_count = le16_to_cpu(ACCESS_ONCE(last->res_count));
2798 	completed = req_count - res_count;
2799 	buffer_dma = le32_to_cpu(last->data_address);
2800 
2801 	if (completed > 0) {
2802 		ctx->mc_buffer_bus = buffer_dma;
2803 		ctx->mc_completed = completed;
2804 	}
2805 
2806 	if (res_count != 0)
2807 		/* Descriptor(s) not done yet, stop iteration */
2808 		return 0;
2809 
2810 	dma_sync_single_range_for_cpu(context->ohci->card.device,
2811 				      buffer_dma & PAGE_MASK,
2812 				      buffer_dma & ~PAGE_MASK,
2813 				      completed, DMA_FROM_DEVICE);
2814 
2815 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2816 		ctx->base.callback.mc(&ctx->base,
2817 				      buffer_dma + completed,
2818 				      ctx->base.callback_data);
2819 		ctx->mc_completed = 0;
2820 	}
2821 
2822 	return 1;
2823 }
2824 
2825 static void flush_ir_buffer_fill(struct iso_context *ctx)
2826 {
2827 	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
2828 				      ctx->mc_buffer_bus & PAGE_MASK,
2829 				      ctx->mc_buffer_bus & ~PAGE_MASK,
2830 				      ctx->mc_completed, DMA_FROM_DEVICE);
2831 
2832 	ctx->base.callback.mc(&ctx->base,
2833 			      ctx->mc_buffer_bus + ctx->mc_completed,
2834 			      ctx->base.callback_data);
2835 	ctx->mc_completed = 0;
2836 }
2837 
2838 static inline void sync_it_packet_for_cpu(struct context *context,
2839 					  struct descriptor *pd)
2840 {
2841 	__le16 control;
2842 	u32 buffer_dma;
2843 
2844 	/* only packets beginning with OUTPUT_MORE* have data buffers */
2845 	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2846 		return;
2847 
2848 	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
2849 	pd += 2;
2850 
2851 	/*
2852 	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
2853 	 * data buffer is in the context program's coherent page and must not
2854 	 * be synced.
2855 	 */
2856 	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
2857 	    (context->current_bus          & PAGE_MASK)) {
2858 		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2859 			return;
2860 		pd++;
2861 	}
2862 
2863 	do {
2864 		buffer_dma = le32_to_cpu(pd->data_address);
2865 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2866 					      buffer_dma & PAGE_MASK,
2867 					      buffer_dma & ~PAGE_MASK,
2868 					      le16_to_cpu(pd->req_count),
2869 					      DMA_TO_DEVICE);
2870 		control = pd->control;
2871 		pd++;
2872 	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
2873 }
2874 
2875 static int handle_it_packet(struct context *context,
2876 			    struct descriptor *d,
2877 			    struct descriptor *last)
2878 {
2879 	struct iso_context *ctx =
2880 		container_of(context, struct iso_context, context);
2881 	struct descriptor *pd;
2882 	__be32 *ctx_hdr;
2883 
2884 	for (pd = d; pd <= last; pd++)
2885 		if (pd->transfer_status)
2886 			break;
2887 	if (pd > last)
2888 		/* Descriptor(s) not done yet, stop iteration */
2889 		return 0;
2890 
2891 	sync_it_packet_for_cpu(context, d);
2892 
2893 	if (ctx->header_length + 4 > PAGE_SIZE)
2894 		flush_iso_completions(ctx);
2895 
2896 	ctx_hdr = ctx->header + ctx->header_length;
2897 	ctx->last_timestamp = le16_to_cpu(last->res_count);
2898 	/* Present this value as big-endian to match the receive code */
2899 	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
2900 			       le16_to_cpu(pd->res_count));
2901 	ctx->header_length += 4;
2902 
2903 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2904 		flush_iso_completions(ctx);
2905 
2906 	return 1;
2907 }
2908 
2909 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2910 {
2911 	u32 hi = channels >> 32, lo = channels;
2912 
2913 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2914 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2915 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2916 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2917 	mmiowb();
2918 	ohci->mc_channels = channels;
2919 }
2920 
2921 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2922 				int type, int channel, size_t header_size)
2923 {
2924 	struct fw_ohci *ohci = fw_ohci(card);
2925 	struct iso_context *uninitialized_var(ctx);
2926 	descriptor_callback_t uninitialized_var(callback);
2927 	u64 *uninitialized_var(channels);
2928 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2929 	int index, ret = -EBUSY;
2930 
2931 	spin_lock_irq(&ohci->lock);
2932 
2933 	switch (type) {
2934 	case FW_ISO_CONTEXT_TRANSMIT:
2935 		mask     = &ohci->it_context_mask;
2936 		callback = handle_it_packet;
2937 		index    = ffs(*mask) - 1;
2938 		if (index >= 0) {
2939 			*mask &= ~(1 << index);
2940 			regs = OHCI1394_IsoXmitContextBase(index);
2941 			ctx  = &ohci->it_context_list[index];
2942 		}
2943 		break;
2944 
2945 	case FW_ISO_CONTEXT_RECEIVE:
2946 		channels = &ohci->ir_context_channels;
2947 		mask     = &ohci->ir_context_mask;
2948 		callback = handle_ir_packet_per_buffer;
2949 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2950 		if (index >= 0) {
2951 			*channels &= ~(1ULL << channel);
2952 			*mask     &= ~(1 << index);
2953 			regs = OHCI1394_IsoRcvContextBase(index);
2954 			ctx  = &ohci->ir_context_list[index];
2955 		}
2956 		break;
2957 
2958 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2959 		mask     = &ohci->ir_context_mask;
2960 		callback = handle_ir_buffer_fill;
2961 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2962 		if (index >= 0) {
2963 			ohci->mc_allocated = true;
2964 			*mask &= ~(1 << index);
2965 			regs = OHCI1394_IsoRcvContextBase(index);
2966 			ctx  = &ohci->ir_context_list[index];
2967 		}
2968 		break;
2969 
2970 	default:
2971 		index = -1;
2972 		ret = -ENOSYS;
2973 	}
2974 
2975 	spin_unlock_irq(&ohci->lock);
2976 
2977 	if (index < 0)
2978 		return ERR_PTR(ret);
2979 
2980 	memset(ctx, 0, sizeof(*ctx));
2981 	ctx->header_length = 0;
2982 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2983 	if (ctx->header == NULL) {
2984 		ret = -ENOMEM;
2985 		goto out;
2986 	}
2987 	ret = context_init(&ctx->context, ohci, regs, callback);
2988 	if (ret < 0)
2989 		goto out_with_header;
2990 
2991 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
2992 		set_multichannel_mask(ohci, 0);
2993 		ctx->mc_completed = 0;
2994 	}
2995 
2996 	return &ctx->base;
2997 
2998  out_with_header:
2999 	free_page((unsigned long)ctx->header);
3000  out:
3001 	spin_lock_irq(&ohci->lock);
3002 
3003 	switch (type) {
3004 	case FW_ISO_CONTEXT_RECEIVE:
3005 		*channels |= 1ULL << channel;
3006 		break;
3007 
3008 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3009 		ohci->mc_allocated = false;
3010 		break;
3011 	}
3012 	*mask |= 1 << index;
3013 
3014 	spin_unlock_irq(&ohci->lock);
3015 
3016 	return ERR_PTR(ret);
3017 }
3018 
3019 static int ohci_start_iso(struct fw_iso_context *base,
3020 			  s32 cycle, u32 sync, u32 tags)
3021 {
3022 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3023 	struct fw_ohci *ohci = ctx->context.ohci;
3024 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
3025 	int index;
3026 
3027 	/* the controller cannot start without any queued packets */
3028 	if (ctx->context.last->branch_address == 0)
3029 		return -ENODATA;
3030 
3031 	switch (ctx->base.type) {
3032 	case FW_ISO_CONTEXT_TRANSMIT:
3033 		index = ctx - ohci->it_context_list;
3034 		match = 0;
3035 		if (cycle >= 0)
3036 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3037 				(cycle & 0x7fff) << 16;
3038 
3039 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3040 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3041 		context_run(&ctx->context, match);
3042 		break;
3043 
3044 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3045 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3046 		/* fall through */
3047 	case FW_ISO_CONTEXT_RECEIVE:
3048 		index = ctx - ohci->ir_context_list;
3049 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
3050 		if (cycle >= 0) {
3051 			match |= (cycle & 0x07fff) << 12;
3052 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3053 		}
3054 
3055 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3056 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3057 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3058 		context_run(&ctx->context, control);
3059 
3060 		ctx->sync = sync;
3061 		ctx->tags = tags;
3062 
3063 		break;
3064 	}
3065 
3066 	return 0;
3067 }
3068 
3069 static int ohci_stop_iso(struct fw_iso_context *base)
3070 {
3071 	struct fw_ohci *ohci = fw_ohci(base->card);
3072 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3073 	int index;
3074 
3075 	switch (ctx->base.type) {
3076 	case FW_ISO_CONTEXT_TRANSMIT:
3077 		index = ctx - ohci->it_context_list;
3078 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3079 		break;
3080 
3081 	case FW_ISO_CONTEXT_RECEIVE:
3082 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3083 		index = ctx - ohci->ir_context_list;
3084 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3085 		break;
3086 	}
3087 	flush_writes(ohci);
3088 	context_stop(&ctx->context);
3089 	tasklet_kill(&ctx->context.tasklet);
3090 
3091 	return 0;
3092 }
3093 
3094 static void ohci_free_iso_context(struct fw_iso_context *base)
3095 {
3096 	struct fw_ohci *ohci = fw_ohci(base->card);
3097 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3098 	unsigned long flags;
3099 	int index;
3100 
3101 	ohci_stop_iso(base);
3102 	context_release(&ctx->context);
3103 	free_page((unsigned long)ctx->header);
3104 
3105 	spin_lock_irqsave(&ohci->lock, flags);
3106 
3107 	switch (base->type) {
3108 	case FW_ISO_CONTEXT_TRANSMIT:
3109 		index = ctx - ohci->it_context_list;
3110 		ohci->it_context_mask |= 1 << index;
3111 		break;
3112 
3113 	case FW_ISO_CONTEXT_RECEIVE:
3114 		index = ctx - ohci->ir_context_list;
3115 		ohci->ir_context_mask |= 1 << index;
3116 		ohci->ir_context_channels |= 1ULL << base->channel;
3117 		break;
3118 
3119 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3120 		index = ctx - ohci->ir_context_list;
3121 		ohci->ir_context_mask |= 1 << index;
3122 		ohci->ir_context_channels |= ohci->mc_channels;
3123 		ohci->mc_channels = 0;
3124 		ohci->mc_allocated = false;
3125 		break;
3126 	}
3127 
3128 	spin_unlock_irqrestore(&ohci->lock, flags);
3129 }
3130 
3131 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3132 {
3133 	struct fw_ohci *ohci = fw_ohci(base->card);
3134 	unsigned long flags;
3135 	int ret;
3136 
3137 	switch (base->type) {
3138 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3139 
3140 		spin_lock_irqsave(&ohci->lock, flags);
3141 
3142 		/* Don't allow multichannel to grab other contexts' channels. */
3143 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3144 			*channels = ohci->ir_context_channels;
3145 			ret = -EBUSY;
3146 		} else {
3147 			set_multichannel_mask(ohci, *channels);
3148 			ret = 0;
3149 		}
3150 
3151 		spin_unlock_irqrestore(&ohci->lock, flags);
3152 
3153 		break;
3154 	default:
3155 		ret = -EINVAL;
3156 	}
3157 
3158 	return ret;
3159 }
3160 
3161 #ifdef CONFIG_PM
3162 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3163 {
3164 	int i;
3165 	struct iso_context *ctx;
3166 
3167 	for (i = 0 ; i < ohci->n_ir ; i++) {
3168 		ctx = &ohci->ir_context_list[i];
3169 		if (ctx->context.running)
3170 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3171 	}
3172 
3173 	for (i = 0 ; i < ohci->n_it ; i++) {
3174 		ctx = &ohci->it_context_list[i];
3175 		if (ctx->context.running)
3176 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3177 	}
3178 }
3179 #endif
3180 
3181 static int queue_iso_transmit(struct iso_context *ctx,
3182 			      struct fw_iso_packet *packet,
3183 			      struct fw_iso_buffer *buffer,
3184 			      unsigned long payload)
3185 {
3186 	struct descriptor *d, *last, *pd;
3187 	struct fw_iso_packet *p;
3188 	__le32 *header;
3189 	dma_addr_t d_bus, page_bus;
3190 	u32 z, header_z, payload_z, irq;
3191 	u32 payload_index, payload_end_index, next_page_index;
3192 	int page, end_page, i, length, offset;
3193 
3194 	p = packet;
3195 	payload_index = payload;
3196 
3197 	if (p->skip)
3198 		z = 1;
3199 	else
3200 		z = 2;
3201 	if (p->header_length > 0)
3202 		z++;
3203 
3204 	/* Determine the first page the payload isn't contained in. */
3205 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3206 	if (p->payload_length > 0)
3207 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
3208 	else
3209 		payload_z = 0;
3210 
3211 	z += payload_z;
3212 
3213 	/* Get header size in number of descriptors. */
3214 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3215 
3216 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3217 	if (d == NULL)
3218 		return -ENOMEM;
3219 
3220 	if (!p->skip) {
3221 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3222 		d[0].req_count = cpu_to_le16(8);
3223 		/*
3224 		 * Link the skip address to this descriptor itself.  This causes
3225 		 * a context to skip a cycle whenever lost cycles or FIFO
3226 		 * overruns occur, without dropping the data.  The application
3227 		 * should then decide whether this is an error condition or not.
3228 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
3229 		 */
3230 		d[0].branch_address = cpu_to_le32(d_bus | z);
3231 
3232 		header = (__le32 *) &d[1];
3233 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
3234 					IT_HEADER_TAG(p->tag) |
3235 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
3236 					IT_HEADER_CHANNEL(ctx->base.channel) |
3237 					IT_HEADER_SPEED(ctx->base.speed));
3238 		header[1] =
3239 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
3240 							  p->payload_length));
3241 	}
3242 
3243 	if (p->header_length > 0) {
3244 		d[2].req_count    = cpu_to_le16(p->header_length);
3245 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3246 		memcpy(&d[z], p->header, p->header_length);
3247 	}
3248 
3249 	pd = d + z - payload_z;
3250 	payload_end_index = payload_index + p->payload_length;
3251 	for (i = 0; i < payload_z; i++) {
3252 		page               = payload_index >> PAGE_SHIFT;
3253 		offset             = payload_index & ~PAGE_MASK;
3254 		next_page_index    = (page + 1) << PAGE_SHIFT;
3255 		length             =
3256 			min(next_page_index, payload_end_index) - payload_index;
3257 		pd[i].req_count    = cpu_to_le16(length);
3258 
3259 		page_bus = page_private(buffer->pages[page]);
3260 		pd[i].data_address = cpu_to_le32(page_bus + offset);
3261 
3262 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3263 						 page_bus, offset, length,
3264 						 DMA_TO_DEVICE);
3265 
3266 		payload_index += length;
3267 	}
3268 
3269 	if (p->interrupt)
3270 		irq = DESCRIPTOR_IRQ_ALWAYS;
3271 	else
3272 		irq = DESCRIPTOR_NO_IRQ;
3273 
3274 	last = z == 2 ? d : d + z - 1;
3275 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3276 				     DESCRIPTOR_STATUS |
3277 				     DESCRIPTOR_BRANCH_ALWAYS |
3278 				     irq);
3279 
3280 	context_append(&ctx->context, d, z, header_z);
3281 
3282 	return 0;
3283 }
3284 
3285 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3286 				       struct fw_iso_packet *packet,
3287 				       struct fw_iso_buffer *buffer,
3288 				       unsigned long payload)
3289 {
3290 	struct device *device = ctx->context.ohci->card.device;
3291 	struct descriptor *d, *pd;
3292 	dma_addr_t d_bus, page_bus;
3293 	u32 z, header_z, rest;
3294 	int i, j, length;
3295 	int page, offset, packet_count, header_size, payload_per_buffer;
3296 
3297 	/*
3298 	 * The OHCI controller puts the isochronous header and trailer in the
3299 	 * buffer, so we need at least 8 bytes.
3300 	 */
3301 	packet_count = packet->header_length / ctx->base.header_size;
3302 	header_size  = max(ctx->base.header_size, (size_t)8);
3303 
3304 	/* Get header size in number of descriptors. */
3305 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3306 	page     = payload >> PAGE_SHIFT;
3307 	offset   = payload & ~PAGE_MASK;
3308 	payload_per_buffer = packet->payload_length / packet_count;
3309 
3310 	for (i = 0; i < packet_count; i++) {
3311 		/* d points to the header descriptor */
3312 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3313 		d = context_get_descriptors(&ctx->context,
3314 				z + header_z, &d_bus);
3315 		if (d == NULL)
3316 			return -ENOMEM;
3317 
3318 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3319 					      DESCRIPTOR_INPUT_MORE);
3320 		if (packet->skip && i == 0)
3321 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3322 		d->req_count    = cpu_to_le16(header_size);
3323 		d->res_count    = d->req_count;
3324 		d->transfer_status = 0;
3325 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3326 
3327 		rest = payload_per_buffer;
3328 		pd = d;
3329 		for (j = 1; j < z; j++) {
3330 			pd++;
3331 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3332 						  DESCRIPTOR_INPUT_MORE);
3333 
3334 			if (offset + rest < PAGE_SIZE)
3335 				length = rest;
3336 			else
3337 				length = PAGE_SIZE - offset;
3338 			pd->req_count = cpu_to_le16(length);
3339 			pd->res_count = pd->req_count;
3340 			pd->transfer_status = 0;
3341 
3342 			page_bus = page_private(buffer->pages[page]);
3343 			pd->data_address = cpu_to_le32(page_bus + offset);
3344 
3345 			dma_sync_single_range_for_device(device, page_bus,
3346 							 offset, length,
3347 							 DMA_FROM_DEVICE);
3348 
3349 			offset = (offset + length) & ~PAGE_MASK;
3350 			rest -= length;
3351 			if (offset == 0)
3352 				page++;
3353 		}
3354 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3355 					  DESCRIPTOR_INPUT_LAST |
3356 					  DESCRIPTOR_BRANCH_ALWAYS);
3357 		if (packet->interrupt && i == packet_count - 1)
3358 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3359 
3360 		context_append(&ctx->context, d, z, header_z);
3361 	}
3362 
3363 	return 0;
3364 }
3365 
3366 static int queue_iso_buffer_fill(struct iso_context *ctx,
3367 				 struct fw_iso_packet *packet,
3368 				 struct fw_iso_buffer *buffer,
3369 				 unsigned long payload)
3370 {
3371 	struct descriptor *d;
3372 	dma_addr_t d_bus, page_bus;
3373 	int page, offset, rest, z, i, length;
3374 
3375 	page   = payload >> PAGE_SHIFT;
3376 	offset = payload & ~PAGE_MASK;
3377 	rest   = packet->payload_length;
3378 
3379 	/* We need one descriptor for each page in the buffer. */
3380 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3381 
3382 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3383 		return -EFAULT;
3384 
3385 	for (i = 0; i < z; i++) {
3386 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3387 		if (d == NULL)
3388 			return -ENOMEM;
3389 
3390 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3391 					 DESCRIPTOR_BRANCH_ALWAYS);
3392 		if (packet->skip && i == 0)
3393 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3394 		if (packet->interrupt && i == z - 1)
3395 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3396 
3397 		if (offset + rest < PAGE_SIZE)
3398 			length = rest;
3399 		else
3400 			length = PAGE_SIZE - offset;
3401 		d->req_count = cpu_to_le16(length);
3402 		d->res_count = d->req_count;
3403 		d->transfer_status = 0;
3404 
3405 		page_bus = page_private(buffer->pages[page]);
3406 		d->data_address = cpu_to_le32(page_bus + offset);
3407 
3408 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3409 						 page_bus, offset, length,
3410 						 DMA_FROM_DEVICE);
3411 
3412 		rest -= length;
3413 		offset = 0;
3414 		page++;
3415 
3416 		context_append(&ctx->context, d, 1, 0);
3417 	}
3418 
3419 	return 0;
3420 }
3421 
3422 static int ohci_queue_iso(struct fw_iso_context *base,
3423 			  struct fw_iso_packet *packet,
3424 			  struct fw_iso_buffer *buffer,
3425 			  unsigned long payload)
3426 {
3427 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3428 	unsigned long flags;
3429 	int ret = -ENOSYS;
3430 
3431 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3432 	switch (base->type) {
3433 	case FW_ISO_CONTEXT_TRANSMIT:
3434 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
3435 		break;
3436 	case FW_ISO_CONTEXT_RECEIVE:
3437 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3438 		break;
3439 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3440 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3441 		break;
3442 	}
3443 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3444 
3445 	return ret;
3446 }
3447 
3448 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3449 {
3450 	struct context *ctx =
3451 			&container_of(base, struct iso_context, base)->context;
3452 
3453 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3454 }
3455 
3456 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3457 {
3458 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3459 	int ret = 0;
3460 
3461 	tasklet_disable(&ctx->context.tasklet);
3462 
3463 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3464 		context_tasklet((unsigned long)&ctx->context);
3465 
3466 		switch (base->type) {
3467 		case FW_ISO_CONTEXT_TRANSMIT:
3468 		case FW_ISO_CONTEXT_RECEIVE:
3469 			if (ctx->header_length != 0)
3470 				flush_iso_completions(ctx);
3471 			break;
3472 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3473 			if (ctx->mc_completed != 0)
3474 				flush_ir_buffer_fill(ctx);
3475 			break;
3476 		default:
3477 			ret = -ENOSYS;
3478 		}
3479 
3480 		clear_bit_unlock(0, &ctx->flushing_completions);
3481 		smp_mb__after_clear_bit();
3482 	}
3483 
3484 	tasklet_enable(&ctx->context.tasklet);
3485 
3486 	return ret;
3487 }
3488 
3489 static const struct fw_card_driver ohci_driver = {
3490 	.enable			= ohci_enable,
3491 	.read_phy_reg		= ohci_read_phy_reg,
3492 	.update_phy_reg		= ohci_update_phy_reg,
3493 	.set_config_rom		= ohci_set_config_rom,
3494 	.send_request		= ohci_send_request,
3495 	.send_response		= ohci_send_response,
3496 	.cancel_packet		= ohci_cancel_packet,
3497 	.enable_phys_dma	= ohci_enable_phys_dma,
3498 	.read_csr		= ohci_read_csr,
3499 	.write_csr		= ohci_write_csr,
3500 
3501 	.allocate_iso_context	= ohci_allocate_iso_context,
3502 	.free_iso_context	= ohci_free_iso_context,
3503 	.set_iso_channels	= ohci_set_iso_channels,
3504 	.queue_iso		= ohci_queue_iso,
3505 	.flush_queue_iso	= ohci_flush_queue_iso,
3506 	.flush_iso_completions	= ohci_flush_iso_completions,
3507 	.start_iso		= ohci_start_iso,
3508 	.stop_iso		= ohci_stop_iso,
3509 };
3510 
3511 #ifdef CONFIG_PPC_PMAC
3512 static void pmac_ohci_on(struct pci_dev *dev)
3513 {
3514 	if (machine_is(powermac)) {
3515 		struct device_node *ofn = pci_device_to_OF_node(dev);
3516 
3517 		if (ofn) {
3518 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3519 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3520 		}
3521 	}
3522 }
3523 
3524 static void pmac_ohci_off(struct pci_dev *dev)
3525 {
3526 	if (machine_is(powermac)) {
3527 		struct device_node *ofn = pci_device_to_OF_node(dev);
3528 
3529 		if (ofn) {
3530 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3531 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3532 		}
3533 	}
3534 }
3535 #else
3536 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3537 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3538 #endif /* CONFIG_PPC_PMAC */
3539 
3540 static int pci_probe(struct pci_dev *dev,
3541 			       const struct pci_device_id *ent)
3542 {
3543 	struct fw_ohci *ohci;
3544 	u32 bus_options, max_receive, link_speed, version;
3545 	u64 guid;
3546 	int i, err;
3547 	size_t size;
3548 
3549 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3550 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3551 		return -ENOSYS;
3552 	}
3553 
3554 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3555 	if (ohci == NULL) {
3556 		err = -ENOMEM;
3557 		goto fail;
3558 	}
3559 
3560 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3561 
3562 	pmac_ohci_on(dev);
3563 
3564 	err = pci_enable_device(dev);
3565 	if (err) {
3566 		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3567 		goto fail_free;
3568 	}
3569 
3570 	pci_set_master(dev);
3571 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3572 	pci_set_drvdata(dev, ohci);
3573 
3574 	spin_lock_init(&ohci->lock);
3575 	mutex_init(&ohci->phy_reg_mutex);
3576 
3577 	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3578 
3579 	if (!(pci_resource_flags(dev, 0) & IORESOURCE_MEM) ||
3580 	    pci_resource_len(dev, 0) < OHCI1394_REGISTER_SIZE) {
3581 		dev_err(&dev->dev, "invalid MMIO resource\n");
3582 		err = -ENXIO;
3583 		goto fail_disable;
3584 	}
3585 
3586 	err = pci_request_region(dev, 0, ohci_driver_name);
3587 	if (err) {
3588 		dev_err(&dev->dev, "MMIO resource unavailable\n");
3589 		goto fail_disable;
3590 	}
3591 
3592 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3593 	if (ohci->registers == NULL) {
3594 		dev_err(&dev->dev, "failed to remap registers\n");
3595 		err = -ENXIO;
3596 		goto fail_iomem;
3597 	}
3598 
3599 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3600 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3601 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3602 		     ohci_quirks[i].device == dev->device) &&
3603 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3604 		     ohci_quirks[i].revision >= dev->revision)) {
3605 			ohci->quirks = ohci_quirks[i].flags;
3606 			break;
3607 		}
3608 	if (param_quirks)
3609 		ohci->quirks = param_quirks;
3610 
3611 	/*
3612 	 * Because dma_alloc_coherent() allocates at least one page,
3613 	 * we save space by using a common buffer for the AR request/
3614 	 * response descriptors and the self IDs buffer.
3615 	 */
3616 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3617 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3618 	ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3619 					       PAGE_SIZE,
3620 					       &ohci->misc_buffer_bus,
3621 					       GFP_KERNEL);
3622 	if (!ohci->misc_buffer) {
3623 		err = -ENOMEM;
3624 		goto fail_iounmap;
3625 	}
3626 
3627 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3628 			      OHCI1394_AsReqRcvContextControlSet);
3629 	if (err < 0)
3630 		goto fail_misc_buf;
3631 
3632 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3633 			      OHCI1394_AsRspRcvContextControlSet);
3634 	if (err < 0)
3635 		goto fail_arreq_ctx;
3636 
3637 	err = context_init(&ohci->at_request_ctx, ohci,
3638 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3639 	if (err < 0)
3640 		goto fail_arrsp_ctx;
3641 
3642 	err = context_init(&ohci->at_response_ctx, ohci,
3643 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3644 	if (err < 0)
3645 		goto fail_atreq_ctx;
3646 
3647 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3648 	ohci->ir_context_channels = ~0ULL;
3649 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3650 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3651 	ohci->ir_context_mask = ohci->ir_context_support;
3652 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3653 	size = sizeof(struct iso_context) * ohci->n_ir;
3654 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3655 
3656 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3657 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3658 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3659 	ohci->it_context_mask = ohci->it_context_support;
3660 	ohci->n_it = hweight32(ohci->it_context_mask);
3661 	size = sizeof(struct iso_context) * ohci->n_it;
3662 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3663 
3664 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3665 		err = -ENOMEM;
3666 		goto fail_contexts;
3667 	}
3668 
3669 	ohci->self_id_cpu = ohci->misc_buffer     + PAGE_SIZE/2;
3670 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3671 
3672 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3673 	max_receive = (bus_options >> 12) & 0xf;
3674 	link_speed = bus_options & 0x7;
3675 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3676 		reg_read(ohci, OHCI1394_GUIDLo);
3677 
3678 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3679 	if (err)
3680 		goto fail_contexts;
3681 
3682 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3683 	dev_notice(&dev->dev,
3684 		  "added OHCI v%x.%x device as card %d, "
3685 		  "%d IR + %d IT contexts, quirks 0x%x\n",
3686 		  version >> 16, version & 0xff, ohci->card.index,
3687 		  ohci->n_ir, ohci->n_it, ohci->quirks);
3688 
3689 	return 0;
3690 
3691  fail_contexts:
3692 	kfree(ohci->ir_context_list);
3693 	kfree(ohci->it_context_list);
3694 	context_release(&ohci->at_response_ctx);
3695  fail_atreq_ctx:
3696 	context_release(&ohci->at_request_ctx);
3697  fail_arrsp_ctx:
3698 	ar_context_release(&ohci->ar_response_ctx);
3699  fail_arreq_ctx:
3700 	ar_context_release(&ohci->ar_request_ctx);
3701  fail_misc_buf:
3702 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3703 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3704  fail_iounmap:
3705 	pci_iounmap(dev, ohci->registers);
3706  fail_iomem:
3707 	pci_release_region(dev, 0);
3708  fail_disable:
3709 	pci_disable_device(dev);
3710  fail_free:
3711 	kfree(ohci);
3712 	pmac_ohci_off(dev);
3713  fail:
3714 	if (err == -ENOMEM)
3715 		dev_err(&dev->dev, "out of memory\n");
3716 
3717 	return err;
3718 }
3719 
3720 static void pci_remove(struct pci_dev *dev)
3721 {
3722 	struct fw_ohci *ohci;
3723 
3724 	ohci = pci_get_drvdata(dev);
3725 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3726 	flush_writes(ohci);
3727 	cancel_work_sync(&ohci->bus_reset_work);
3728 	fw_core_remove_card(&ohci->card);
3729 
3730 	/*
3731 	 * FIXME: Fail all pending packets here, now that the upper
3732 	 * layers can't queue any more.
3733 	 */
3734 
3735 	software_reset(ohci);
3736 	free_irq(dev->irq, ohci);
3737 
3738 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3739 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3740 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3741 	if (ohci->config_rom)
3742 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3743 				  ohci->config_rom, ohci->config_rom_bus);
3744 	ar_context_release(&ohci->ar_request_ctx);
3745 	ar_context_release(&ohci->ar_response_ctx);
3746 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3747 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3748 	context_release(&ohci->at_request_ctx);
3749 	context_release(&ohci->at_response_ctx);
3750 	kfree(ohci->it_context_list);
3751 	kfree(ohci->ir_context_list);
3752 	pci_disable_msi(dev);
3753 	pci_iounmap(dev, ohci->registers);
3754 	pci_release_region(dev, 0);
3755 	pci_disable_device(dev);
3756 	kfree(ohci);
3757 	pmac_ohci_off(dev);
3758 
3759 	dev_notice(&dev->dev, "removed fw-ohci device\n");
3760 }
3761 
3762 #ifdef CONFIG_PM
3763 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3764 {
3765 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3766 	int err;
3767 
3768 	software_reset(ohci);
3769 	free_irq(dev->irq, ohci);
3770 	pci_disable_msi(dev);
3771 	err = pci_save_state(dev);
3772 	if (err) {
3773 		dev_err(&dev->dev, "pci_save_state failed\n");
3774 		return err;
3775 	}
3776 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3777 	if (err)
3778 		dev_err(&dev->dev, "pci_set_power_state failed with %d\n", err);
3779 	pmac_ohci_off(dev);
3780 
3781 	return 0;
3782 }
3783 
3784 static int pci_resume(struct pci_dev *dev)
3785 {
3786 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3787 	int err;
3788 
3789 	pmac_ohci_on(dev);
3790 	pci_set_power_state(dev, PCI_D0);
3791 	pci_restore_state(dev);
3792 	err = pci_enable_device(dev);
3793 	if (err) {
3794 		dev_err(&dev->dev, "pci_enable_device failed\n");
3795 		return err;
3796 	}
3797 
3798 	/* Some systems don't setup GUID register on resume from ram  */
3799 	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3800 					!reg_read(ohci, OHCI1394_GUIDHi)) {
3801 		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3802 		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3803 	}
3804 
3805 	err = ohci_enable(&ohci->card, NULL, 0);
3806 	if (err)
3807 		return err;
3808 
3809 	ohci_resume_iso_dma(ohci);
3810 
3811 	return 0;
3812 }
3813 #endif
3814 
3815 static const struct pci_device_id pci_table[] = {
3816 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3817 	{ }
3818 };
3819 
3820 MODULE_DEVICE_TABLE(pci, pci_table);
3821 
3822 static struct pci_driver fw_ohci_pci_driver = {
3823 	.name		= ohci_driver_name,
3824 	.id_table	= pci_table,
3825 	.probe		= pci_probe,
3826 	.remove		= pci_remove,
3827 #ifdef CONFIG_PM
3828 	.resume		= pci_resume,
3829 	.suspend	= pci_suspend,
3830 #endif
3831 };
3832 
3833 module_pci_driver(fw_ohci_pci_driver);
3834 
3835 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3836 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3837 MODULE_LICENSE("GPL");
3838 
3839 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3840 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3841 MODULE_ALIAS("ohci1394");
3842 #endif
3843