xref: /linux/drivers/firewire/ohci.c (revision 98f4a2c27c76e7eaf75c2f3f25487fabca62ef3d)
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 
46 #include <asm/byteorder.h>
47 #include <asm/page.h>
48 #include <asm/system.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 	bool running;
129 	bool flushing;
130 
131 	/*
132 	 * List of page-sized buffers for storing DMA descriptors.
133 	 * Head of list contains buffers in use and tail of list contains
134 	 * free buffers.
135 	 */
136 	struct list_head buffer_list;
137 
138 	/*
139 	 * Pointer to a buffer inside buffer_list that contains the tail
140 	 * end of the current DMA program.
141 	 */
142 	struct descriptor_buffer *buffer_tail;
143 
144 	/*
145 	 * The descriptor containing the branch address of the first
146 	 * descriptor that has not yet been filled by the device.
147 	 */
148 	struct descriptor *last;
149 
150 	/*
151 	 * The last descriptor in the DMA program.  It contains the branch
152 	 * address that must be updated upon appending a new descriptor.
153 	 */
154 	struct descriptor *prev;
155 
156 	descriptor_callback_t callback;
157 
158 	struct tasklet_struct tasklet;
159 };
160 
161 #define IT_HEADER_SY(v)          ((v) <<  0)
162 #define IT_HEADER_TCODE(v)       ((v) <<  4)
163 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
164 #define IT_HEADER_TAG(v)         ((v) << 14)
165 #define IT_HEADER_SPEED(v)       ((v) << 16)
166 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
167 
168 struct iso_context {
169 	struct fw_iso_context base;
170 	struct context context;
171 	int excess_bytes;
172 	void *header;
173 	size_t header_length;
174 
175 	u8 sync;
176 	u8 tags;
177 };
178 
179 #define CONFIG_ROM_SIZE 1024
180 
181 struct fw_ohci {
182 	struct fw_card card;
183 
184 	__iomem char *registers;
185 	int node_id;
186 	int generation;
187 	int request_generation;	/* for timestamping incoming requests */
188 	unsigned quirks;
189 	unsigned int pri_req_max;
190 	u32 bus_time;
191 	bool is_root;
192 	bool csr_state_setclear_abdicate;
193 	int n_ir;
194 	int n_it;
195 	/*
196 	 * Spinlock for accessing fw_ohci data.  Never call out of
197 	 * this driver with this lock held.
198 	 */
199 	spinlock_t lock;
200 
201 	struct mutex phy_reg_mutex;
202 
203 	void *misc_buffer;
204 	dma_addr_t misc_buffer_bus;
205 
206 	struct ar_context ar_request_ctx;
207 	struct ar_context ar_response_ctx;
208 	struct context at_request_ctx;
209 	struct context at_response_ctx;
210 
211 	u32 it_context_support;
212 	u32 it_context_mask;     /* unoccupied IT contexts */
213 	struct iso_context *it_context_list;
214 	u64 ir_context_channels; /* unoccupied channels */
215 	u32 ir_context_support;
216 	u32 ir_context_mask;     /* unoccupied IR contexts */
217 	struct iso_context *ir_context_list;
218 	u64 mc_channels; /* channels in use by the multichannel IR context */
219 	bool mc_allocated;
220 
221 	__be32    *config_rom;
222 	dma_addr_t config_rom_bus;
223 	__be32    *next_config_rom;
224 	dma_addr_t next_config_rom_bus;
225 	__be32     next_header;
226 
227 	__le32    *self_id_cpu;
228 	dma_addr_t self_id_bus;
229 	struct tasklet_struct bus_reset_tasklet;
230 
231 	u32 self_id_buffer[512];
232 };
233 
234 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
235 {
236 	return container_of(card, struct fw_ohci, card);
237 }
238 
239 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
240 #define IR_CONTEXT_BUFFER_FILL		0x80000000
241 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
242 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
243 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
244 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
245 
246 #define CONTEXT_RUN	0x8000
247 #define CONTEXT_WAKE	0x1000
248 #define CONTEXT_DEAD	0x0800
249 #define CONTEXT_ACTIVE	0x0400
250 
251 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
252 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
253 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
254 
255 #define OHCI1394_REGISTER_SIZE		0x800
256 #define OHCI_LOOP_COUNT			500
257 #define OHCI1394_PCI_HCI_Control	0x40
258 #define SELF_ID_BUF_SIZE		0x800
259 #define OHCI_TCODE_PHY_PACKET		0x0e
260 #define OHCI_VERSION_1_1		0x010010
261 
262 static char ohci_driver_name[] = KBUILD_MODNAME;
263 
264 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
265 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
266 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
267 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
268 
269 #define QUIRK_CYCLE_TIMER		1
270 #define QUIRK_RESET_PACKET		2
271 #define QUIRK_BE_HEADERS		4
272 #define QUIRK_NO_1394A			8
273 #define QUIRK_NO_MSI			16
274 
275 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
276 static const struct {
277 	unsigned short vendor, device, revision, flags;
278 } ohci_quirks[] = {
279 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
280 		QUIRK_CYCLE_TIMER},
281 
282 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
283 		QUIRK_BE_HEADERS},
284 
285 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
286 		QUIRK_NO_MSI},
287 
288 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
289 		QUIRK_NO_MSI},
290 
291 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
292 		QUIRK_CYCLE_TIMER},
293 
294 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
295 		QUIRK_CYCLE_TIMER},
296 
297 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
298 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
299 
300 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
301 		QUIRK_RESET_PACKET},
302 
303 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
304 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
305 };
306 
307 /* This overrides anything that was found in ohci_quirks[]. */
308 static int param_quirks;
309 module_param_named(quirks, param_quirks, int, 0644);
310 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
311 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
312 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
313 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
314 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
315 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
316 	")");
317 
318 #define OHCI_PARAM_DEBUG_AT_AR		1
319 #define OHCI_PARAM_DEBUG_SELFIDS	2
320 #define OHCI_PARAM_DEBUG_IRQS		4
321 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
322 
323 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
324 
325 static int param_debug;
326 module_param_named(debug, param_debug, int, 0644);
327 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
328 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
329 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
330 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
331 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
332 	", or a combination, or all = -1)");
333 
334 static void log_irqs(u32 evt)
335 {
336 	if (likely(!(param_debug &
337 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
338 		return;
339 
340 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
341 	    !(evt & OHCI1394_busReset))
342 		return;
343 
344 	fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
345 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
346 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
347 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
348 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
349 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
350 	    evt & OHCI1394_isochRx		? " IR"			: "",
351 	    evt & OHCI1394_isochTx		? " IT"			: "",
352 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
353 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
354 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
355 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
356 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
357 	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
358 	    evt & OHCI1394_busReset		? " busReset"		: "",
359 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
360 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
361 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
362 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
363 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
364 		    OHCI1394_cycleInconsistent |
365 		    OHCI1394_regAccessFail | OHCI1394_busReset)
366 						? " ?"			: "");
367 }
368 
369 static const char *speed[] = {
370 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
371 };
372 static const char *power[] = {
373 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
374 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
375 };
376 static const char port[] = { '.', '-', 'p', 'c', };
377 
378 static char _p(u32 *s, int shift)
379 {
380 	return port[*s >> shift & 3];
381 }
382 
383 static void log_selfids(int node_id, int generation, int self_id_count, u32 *s)
384 {
385 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
386 		return;
387 
388 	fw_notify("%d selfIDs, generation %d, local node ID %04x\n",
389 		  self_id_count, generation, node_id);
390 
391 	for (; self_id_count--; ++s)
392 		if ((*s & 1 << 23) == 0)
393 			fw_notify("selfID 0: %08x, phy %d [%c%c%c] "
394 			    "%s gc=%d %s %s%s%s\n",
395 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
396 			    speed[*s >> 14 & 3], *s >> 16 & 63,
397 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
398 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
399 		else
400 			fw_notify("selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
401 			    *s, *s >> 24 & 63,
402 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
403 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
404 }
405 
406 static const char *evts[] = {
407 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
408 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
409 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
410 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
411 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
412 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
413 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
414 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
415 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
416 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
417 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
418 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
419 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
420 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
421 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
422 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
423 	[0x20] = "pending/cancelled",
424 };
425 static const char *tcodes[] = {
426 	[0x0] = "QW req",		[0x1] = "BW req",
427 	[0x2] = "W resp",		[0x3] = "-reserved-",
428 	[0x4] = "QR req",		[0x5] = "BR req",
429 	[0x6] = "QR resp",		[0x7] = "BR resp",
430 	[0x8] = "cycle start",		[0x9] = "Lk req",
431 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
432 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
433 	[0xe] = "link internal",	[0xf] = "-reserved-",
434 };
435 
436 static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
437 {
438 	int tcode = header[0] >> 4 & 0xf;
439 	char specific[12];
440 
441 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
442 		return;
443 
444 	if (unlikely(evt >= ARRAY_SIZE(evts)))
445 			evt = 0x1f;
446 
447 	if (evt == OHCI1394_evt_bus_reset) {
448 		fw_notify("A%c evt_bus_reset, generation %d\n",
449 		    dir, (header[2] >> 16) & 0xff);
450 		return;
451 	}
452 
453 	switch (tcode) {
454 	case 0x0: case 0x6: case 0x8:
455 		snprintf(specific, sizeof(specific), " = %08x",
456 			 be32_to_cpu((__force __be32)header[3]));
457 		break;
458 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
459 		snprintf(specific, sizeof(specific), " %x,%x",
460 			 header[3] >> 16, header[3] & 0xffff);
461 		break;
462 	default:
463 		specific[0] = '\0';
464 	}
465 
466 	switch (tcode) {
467 	case 0xa:
468 		fw_notify("A%c %s, %s\n", dir, evts[evt], tcodes[tcode]);
469 		break;
470 	case 0xe:
471 		fw_notify("A%c %s, PHY %08x %08x\n",
472 			  dir, evts[evt], header[1], header[2]);
473 		break;
474 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
475 		fw_notify("A%c spd %x tl %02x, "
476 		    "%04x -> %04x, %s, "
477 		    "%s, %04x%08x%s\n",
478 		    dir, speed, header[0] >> 10 & 0x3f,
479 		    header[1] >> 16, header[0] >> 16, evts[evt],
480 		    tcodes[tcode], header[1] & 0xffff, header[2], specific);
481 		break;
482 	default:
483 		fw_notify("A%c spd %x tl %02x, "
484 		    "%04x -> %04x, %s, "
485 		    "%s%s\n",
486 		    dir, speed, header[0] >> 10 & 0x3f,
487 		    header[1] >> 16, header[0] >> 16, evts[evt],
488 		    tcodes[tcode], specific);
489 	}
490 }
491 
492 #else
493 
494 #define param_debug 0
495 static inline void log_irqs(u32 evt) {}
496 static inline void log_selfids(int node_id, int generation, int self_id_count, u32 *s) {}
497 static inline void log_ar_at_event(char dir, int speed, u32 *header, int evt) {}
498 
499 #endif /* CONFIG_FIREWIRE_OHCI_DEBUG */
500 
501 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
502 {
503 	writel(data, ohci->registers + offset);
504 }
505 
506 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
507 {
508 	return readl(ohci->registers + offset);
509 }
510 
511 static inline void flush_writes(const struct fw_ohci *ohci)
512 {
513 	/* Do a dummy read to flush writes. */
514 	reg_read(ohci, OHCI1394_Version);
515 }
516 
517 static int read_phy_reg(struct fw_ohci *ohci, int addr)
518 {
519 	u32 val;
520 	int i;
521 
522 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
523 	for (i = 0; i < 3 + 100; i++) {
524 		val = reg_read(ohci, OHCI1394_PhyControl);
525 		if (val & OHCI1394_PhyControl_ReadDone)
526 			return OHCI1394_PhyControl_ReadData(val);
527 
528 		/*
529 		 * Try a few times without waiting.  Sleeping is necessary
530 		 * only when the link/PHY interface is busy.
531 		 */
532 		if (i >= 3)
533 			msleep(1);
534 	}
535 	fw_error("failed to read phy reg\n");
536 
537 	return -EBUSY;
538 }
539 
540 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
541 {
542 	int i;
543 
544 	reg_write(ohci, OHCI1394_PhyControl,
545 		  OHCI1394_PhyControl_Write(addr, val));
546 	for (i = 0; i < 3 + 100; i++) {
547 		val = reg_read(ohci, OHCI1394_PhyControl);
548 		if (!(val & OHCI1394_PhyControl_WritePending))
549 			return 0;
550 
551 		if (i >= 3)
552 			msleep(1);
553 	}
554 	fw_error("failed to write phy reg\n");
555 
556 	return -EBUSY;
557 }
558 
559 static int update_phy_reg(struct fw_ohci *ohci, int addr,
560 			  int clear_bits, int set_bits)
561 {
562 	int ret = read_phy_reg(ohci, addr);
563 	if (ret < 0)
564 		return ret;
565 
566 	/*
567 	 * The interrupt status bits are cleared by writing a one bit.
568 	 * Avoid clearing them unless explicitly requested in set_bits.
569 	 */
570 	if (addr == 5)
571 		clear_bits |= PHY_INT_STATUS_BITS;
572 
573 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
574 }
575 
576 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
577 {
578 	int ret;
579 
580 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
581 	if (ret < 0)
582 		return ret;
583 
584 	return read_phy_reg(ohci, addr);
585 }
586 
587 static int ohci_read_phy_reg(struct fw_card *card, int addr)
588 {
589 	struct fw_ohci *ohci = fw_ohci(card);
590 	int ret;
591 
592 	mutex_lock(&ohci->phy_reg_mutex);
593 	ret = read_phy_reg(ohci, addr);
594 	mutex_unlock(&ohci->phy_reg_mutex);
595 
596 	return ret;
597 }
598 
599 static int ohci_update_phy_reg(struct fw_card *card, int addr,
600 			       int clear_bits, int set_bits)
601 {
602 	struct fw_ohci *ohci = fw_ohci(card);
603 	int ret;
604 
605 	mutex_lock(&ohci->phy_reg_mutex);
606 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
607 	mutex_unlock(&ohci->phy_reg_mutex);
608 
609 	return ret;
610 }
611 
612 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
613 {
614 	return page_private(ctx->pages[i]);
615 }
616 
617 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
618 {
619 	struct descriptor *d;
620 
621 	d = &ctx->descriptors[index];
622 	d->branch_address  &= cpu_to_le32(~0xf);
623 	d->res_count       =  cpu_to_le16(PAGE_SIZE);
624 	d->transfer_status =  0;
625 
626 	wmb(); /* finish init of new descriptors before branch_address update */
627 	d = &ctx->descriptors[ctx->last_buffer_index];
628 	d->branch_address  |= cpu_to_le32(1);
629 
630 	ctx->last_buffer_index = index;
631 
632 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
633 	flush_writes(ctx->ohci);
634 }
635 
636 static void ar_context_release(struct ar_context *ctx)
637 {
638 	unsigned int i;
639 
640 	if (ctx->buffer)
641 		vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
642 
643 	for (i = 0; i < AR_BUFFERS; i++)
644 		if (ctx->pages[i]) {
645 			dma_unmap_page(ctx->ohci->card.device,
646 				       ar_buffer_bus(ctx, i),
647 				       PAGE_SIZE, DMA_FROM_DEVICE);
648 			__free_page(ctx->pages[i]);
649 		}
650 }
651 
652 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
653 {
654 	if (reg_read(ctx->ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
655 		reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
656 		flush_writes(ctx->ohci);
657 
658 		fw_error("AR error: %s; DMA stopped\n", error_msg);
659 	}
660 	/* FIXME: restart? */
661 }
662 
663 static inline unsigned int ar_next_buffer_index(unsigned int index)
664 {
665 	return (index + 1) % AR_BUFFERS;
666 }
667 
668 static inline unsigned int ar_prev_buffer_index(unsigned int index)
669 {
670 	return (index - 1 + AR_BUFFERS) % AR_BUFFERS;
671 }
672 
673 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
674 {
675 	return ar_next_buffer_index(ctx->last_buffer_index);
676 }
677 
678 /*
679  * We search for the buffer that contains the last AR packet DMA data written
680  * by the controller.
681  */
682 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
683 						 unsigned int *buffer_offset)
684 {
685 	unsigned int i, next_i, last = ctx->last_buffer_index;
686 	__le16 res_count, next_res_count;
687 
688 	i = ar_first_buffer_index(ctx);
689 	res_count = ACCESS_ONCE(ctx->descriptors[i].res_count);
690 
691 	/* A buffer that is not yet completely filled must be the last one. */
692 	while (i != last && res_count == 0) {
693 
694 		/* Peek at the next descriptor. */
695 		next_i = ar_next_buffer_index(i);
696 		rmb(); /* read descriptors in order */
697 		next_res_count = ACCESS_ONCE(
698 				ctx->descriptors[next_i].res_count);
699 		/*
700 		 * If the next descriptor is still empty, we must stop at this
701 		 * descriptor.
702 		 */
703 		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
704 			/*
705 			 * The exception is when the DMA data for one packet is
706 			 * split over three buffers; in this case, the middle
707 			 * buffer's descriptor might be never updated by the
708 			 * controller and look still empty, and we have to peek
709 			 * at the third one.
710 			 */
711 			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
712 				next_i = ar_next_buffer_index(next_i);
713 				rmb();
714 				next_res_count = ACCESS_ONCE(
715 					ctx->descriptors[next_i].res_count);
716 				if (next_res_count != cpu_to_le16(PAGE_SIZE))
717 					goto next_buffer_is_active;
718 			}
719 
720 			break;
721 		}
722 
723 next_buffer_is_active:
724 		i = next_i;
725 		res_count = next_res_count;
726 	}
727 
728 	rmb(); /* read res_count before the DMA data */
729 
730 	*buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
731 	if (*buffer_offset > PAGE_SIZE) {
732 		*buffer_offset = 0;
733 		ar_context_abort(ctx, "corrupted descriptor");
734 	}
735 
736 	return i;
737 }
738 
739 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
740 				    unsigned int end_buffer_index,
741 				    unsigned int end_buffer_offset)
742 {
743 	unsigned int i;
744 
745 	i = ar_first_buffer_index(ctx);
746 	while (i != end_buffer_index) {
747 		dma_sync_single_for_cpu(ctx->ohci->card.device,
748 					ar_buffer_bus(ctx, i),
749 					PAGE_SIZE, DMA_FROM_DEVICE);
750 		i = ar_next_buffer_index(i);
751 	}
752 	if (end_buffer_offset > 0)
753 		dma_sync_single_for_cpu(ctx->ohci->card.device,
754 					ar_buffer_bus(ctx, i),
755 					end_buffer_offset, DMA_FROM_DEVICE);
756 }
757 
758 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
759 #define cond_le32_to_cpu(v) \
760 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
761 #else
762 #define cond_le32_to_cpu(v) le32_to_cpu(v)
763 #endif
764 
765 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
766 {
767 	struct fw_ohci *ohci = ctx->ohci;
768 	struct fw_packet p;
769 	u32 status, length, tcode;
770 	int evt;
771 
772 	p.header[0] = cond_le32_to_cpu(buffer[0]);
773 	p.header[1] = cond_le32_to_cpu(buffer[1]);
774 	p.header[2] = cond_le32_to_cpu(buffer[2]);
775 
776 	tcode = (p.header[0] >> 4) & 0x0f;
777 	switch (tcode) {
778 	case TCODE_WRITE_QUADLET_REQUEST:
779 	case TCODE_READ_QUADLET_RESPONSE:
780 		p.header[3] = (__force __u32) buffer[3];
781 		p.header_length = 16;
782 		p.payload_length = 0;
783 		break;
784 
785 	case TCODE_READ_BLOCK_REQUEST :
786 		p.header[3] = cond_le32_to_cpu(buffer[3]);
787 		p.header_length = 16;
788 		p.payload_length = 0;
789 		break;
790 
791 	case TCODE_WRITE_BLOCK_REQUEST:
792 	case TCODE_READ_BLOCK_RESPONSE:
793 	case TCODE_LOCK_REQUEST:
794 	case TCODE_LOCK_RESPONSE:
795 		p.header[3] = cond_le32_to_cpu(buffer[3]);
796 		p.header_length = 16;
797 		p.payload_length = p.header[3] >> 16;
798 		if (p.payload_length > MAX_ASYNC_PAYLOAD) {
799 			ar_context_abort(ctx, "invalid packet length");
800 			return NULL;
801 		}
802 		break;
803 
804 	case TCODE_WRITE_RESPONSE:
805 	case TCODE_READ_QUADLET_REQUEST:
806 	case OHCI_TCODE_PHY_PACKET:
807 		p.header_length = 12;
808 		p.payload_length = 0;
809 		break;
810 
811 	default:
812 		ar_context_abort(ctx, "invalid tcode");
813 		return NULL;
814 	}
815 
816 	p.payload = (void *) buffer + p.header_length;
817 
818 	/* FIXME: What to do about evt_* errors? */
819 	length = (p.header_length + p.payload_length + 3) / 4;
820 	status = cond_le32_to_cpu(buffer[length]);
821 	evt    = (status >> 16) & 0x1f;
822 
823 	p.ack        = evt - 16;
824 	p.speed      = (status >> 21) & 0x7;
825 	p.timestamp  = status & 0xffff;
826 	p.generation = ohci->request_generation;
827 
828 	log_ar_at_event('R', p.speed, p.header, evt);
829 
830 	/*
831 	 * Several controllers, notably from NEC and VIA, forget to
832 	 * write ack_complete status at PHY packet reception.
833 	 */
834 	if (evt == OHCI1394_evt_no_status &&
835 	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
836 		p.ack = ACK_COMPLETE;
837 
838 	/*
839 	 * The OHCI bus reset handler synthesizes a PHY packet with
840 	 * the new generation number when a bus reset happens (see
841 	 * section 8.4.2.3).  This helps us determine when a request
842 	 * was received and make sure we send the response in the same
843 	 * generation.  We only need this for requests; for responses
844 	 * we use the unique tlabel for finding the matching
845 	 * request.
846 	 *
847 	 * Alas some chips sometimes emit bus reset packets with a
848 	 * wrong generation.  We set the correct generation for these
849 	 * at a slightly incorrect time (in bus_reset_tasklet).
850 	 */
851 	if (evt == OHCI1394_evt_bus_reset) {
852 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
853 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
854 	} else if (ctx == &ohci->ar_request_ctx) {
855 		fw_core_handle_request(&ohci->card, &p);
856 	} else {
857 		fw_core_handle_response(&ohci->card, &p);
858 	}
859 
860 	return buffer + length + 1;
861 }
862 
863 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
864 {
865 	void *next;
866 
867 	while (p < end) {
868 		next = handle_ar_packet(ctx, p);
869 		if (!next)
870 			return p;
871 		p = next;
872 	}
873 
874 	return p;
875 }
876 
877 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
878 {
879 	unsigned int i;
880 
881 	i = ar_first_buffer_index(ctx);
882 	while (i != end_buffer) {
883 		dma_sync_single_for_device(ctx->ohci->card.device,
884 					   ar_buffer_bus(ctx, i),
885 					   PAGE_SIZE, DMA_FROM_DEVICE);
886 		ar_context_link_page(ctx, i);
887 		i = ar_next_buffer_index(i);
888 	}
889 }
890 
891 static void ar_context_tasklet(unsigned long data)
892 {
893 	struct ar_context *ctx = (struct ar_context *)data;
894 	unsigned int end_buffer_index, end_buffer_offset;
895 	void *p, *end;
896 
897 	p = ctx->pointer;
898 	if (!p)
899 		return;
900 
901 	end_buffer_index = ar_search_last_active_buffer(ctx,
902 							&end_buffer_offset);
903 	ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
904 	end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
905 
906 	if (end_buffer_index < ar_first_buffer_index(ctx)) {
907 		/*
908 		 * The filled part of the overall buffer wraps around; handle
909 		 * all packets up to the buffer end here.  If the last packet
910 		 * wraps around, its tail will be visible after the buffer end
911 		 * because the buffer start pages are mapped there again.
912 		 */
913 		void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
914 		p = handle_ar_packets(ctx, p, buffer_end);
915 		if (p < buffer_end)
916 			goto error;
917 		/* adjust p to point back into the actual buffer */
918 		p -= AR_BUFFERS * PAGE_SIZE;
919 	}
920 
921 	p = handle_ar_packets(ctx, p, end);
922 	if (p != end) {
923 		if (p > end)
924 			ar_context_abort(ctx, "inconsistent descriptor");
925 		goto error;
926 	}
927 
928 	ctx->pointer = p;
929 	ar_recycle_buffers(ctx, end_buffer_index);
930 
931 	return;
932 
933 error:
934 	ctx->pointer = NULL;
935 }
936 
937 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
938 			   unsigned int descriptors_offset, u32 regs)
939 {
940 	unsigned int i;
941 	dma_addr_t dma_addr;
942 	struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
943 	struct descriptor *d;
944 
945 	ctx->regs        = regs;
946 	ctx->ohci        = ohci;
947 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
948 
949 	for (i = 0; i < AR_BUFFERS; i++) {
950 		ctx->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32);
951 		if (!ctx->pages[i])
952 			goto out_of_memory;
953 		dma_addr = dma_map_page(ohci->card.device, ctx->pages[i],
954 					0, PAGE_SIZE, DMA_FROM_DEVICE);
955 		if (dma_mapping_error(ohci->card.device, dma_addr)) {
956 			__free_page(ctx->pages[i]);
957 			ctx->pages[i] = NULL;
958 			goto out_of_memory;
959 		}
960 		set_page_private(ctx->pages[i], dma_addr);
961 	}
962 
963 	for (i = 0; i < AR_BUFFERS; i++)
964 		pages[i]              = ctx->pages[i];
965 	for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
966 		pages[AR_BUFFERS + i] = ctx->pages[i];
967 	ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
968 				 -1, PAGE_KERNEL);
969 	if (!ctx->buffer)
970 		goto out_of_memory;
971 
972 	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
973 	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
974 
975 	for (i = 0; i < AR_BUFFERS; i++) {
976 		d = &ctx->descriptors[i];
977 		d->req_count      = cpu_to_le16(PAGE_SIZE);
978 		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
979 						DESCRIPTOR_STATUS |
980 						DESCRIPTOR_BRANCH_ALWAYS);
981 		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
982 		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
983 			ar_next_buffer_index(i) * sizeof(struct descriptor));
984 	}
985 
986 	return 0;
987 
988 out_of_memory:
989 	ar_context_release(ctx);
990 
991 	return -ENOMEM;
992 }
993 
994 static void ar_context_run(struct ar_context *ctx)
995 {
996 	unsigned int i;
997 
998 	for (i = 0; i < AR_BUFFERS; i++)
999 		ar_context_link_page(ctx, i);
1000 
1001 	ctx->pointer = ctx->buffer;
1002 
1003 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1004 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1005 	flush_writes(ctx->ohci);
1006 }
1007 
1008 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1009 {
1010 	__le16 branch;
1011 
1012 	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1013 
1014 	/* figure out which descriptor the branch address goes in */
1015 	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1016 		return d;
1017 	else
1018 		return d + z - 1;
1019 }
1020 
1021 static void context_tasklet(unsigned long data)
1022 {
1023 	struct context *ctx = (struct context *) data;
1024 	struct descriptor *d, *last;
1025 	u32 address;
1026 	int z;
1027 	struct descriptor_buffer *desc;
1028 
1029 	desc = list_entry(ctx->buffer_list.next,
1030 			struct descriptor_buffer, list);
1031 	last = ctx->last;
1032 	while (last->branch_address != 0) {
1033 		struct descriptor_buffer *old_desc = desc;
1034 		address = le32_to_cpu(last->branch_address);
1035 		z = address & 0xf;
1036 		address &= ~0xf;
1037 
1038 		/* If the branch address points to a buffer outside of the
1039 		 * current buffer, advance to the next buffer. */
1040 		if (address < desc->buffer_bus ||
1041 				address >= desc->buffer_bus + desc->used)
1042 			desc = list_entry(desc->list.next,
1043 					struct descriptor_buffer, list);
1044 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1045 		last = find_branch_descriptor(d, z);
1046 
1047 		if (!ctx->callback(ctx, d, last))
1048 			break;
1049 
1050 		if (old_desc != desc) {
1051 			/* If we've advanced to the next buffer, move the
1052 			 * previous buffer to the free list. */
1053 			unsigned long flags;
1054 			old_desc->used = 0;
1055 			spin_lock_irqsave(&ctx->ohci->lock, flags);
1056 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1057 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1058 		}
1059 		ctx->last = last;
1060 	}
1061 }
1062 
1063 /*
1064  * Allocate a new buffer and add it to the list of free buffers for this
1065  * context.  Must be called with ohci->lock held.
1066  */
1067 static int context_add_buffer(struct context *ctx)
1068 {
1069 	struct descriptor_buffer *desc;
1070 	dma_addr_t uninitialized_var(bus_addr);
1071 	int offset;
1072 
1073 	/*
1074 	 * 16MB of descriptors should be far more than enough for any DMA
1075 	 * program.  This will catch run-away userspace or DoS attacks.
1076 	 */
1077 	if (ctx->total_allocation >= 16*1024*1024)
1078 		return -ENOMEM;
1079 
1080 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1081 			&bus_addr, GFP_ATOMIC);
1082 	if (!desc)
1083 		return -ENOMEM;
1084 
1085 	offset = (void *)&desc->buffer - (void *)desc;
1086 	desc->buffer_size = PAGE_SIZE - offset;
1087 	desc->buffer_bus = bus_addr + offset;
1088 	desc->used = 0;
1089 
1090 	list_add_tail(&desc->list, &ctx->buffer_list);
1091 	ctx->total_allocation += PAGE_SIZE;
1092 
1093 	return 0;
1094 }
1095 
1096 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1097 			u32 regs, descriptor_callback_t callback)
1098 {
1099 	ctx->ohci = ohci;
1100 	ctx->regs = regs;
1101 	ctx->total_allocation = 0;
1102 
1103 	INIT_LIST_HEAD(&ctx->buffer_list);
1104 	if (context_add_buffer(ctx) < 0)
1105 		return -ENOMEM;
1106 
1107 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1108 			struct descriptor_buffer, list);
1109 
1110 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1111 	ctx->callback = callback;
1112 
1113 	/*
1114 	 * We put a dummy descriptor in the buffer that has a NULL
1115 	 * branch address and looks like it's been sent.  That way we
1116 	 * have a descriptor to append DMA programs to.
1117 	 */
1118 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1119 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1120 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1121 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1122 	ctx->last = ctx->buffer_tail->buffer;
1123 	ctx->prev = ctx->buffer_tail->buffer;
1124 
1125 	return 0;
1126 }
1127 
1128 static void context_release(struct context *ctx)
1129 {
1130 	struct fw_card *card = &ctx->ohci->card;
1131 	struct descriptor_buffer *desc, *tmp;
1132 
1133 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1134 		dma_free_coherent(card->device, PAGE_SIZE, desc,
1135 			desc->buffer_bus -
1136 			((void *)&desc->buffer - (void *)desc));
1137 }
1138 
1139 /* Must be called with ohci->lock held */
1140 static struct descriptor *context_get_descriptors(struct context *ctx,
1141 						  int z, dma_addr_t *d_bus)
1142 {
1143 	struct descriptor *d = NULL;
1144 	struct descriptor_buffer *desc = ctx->buffer_tail;
1145 
1146 	if (z * sizeof(*d) > desc->buffer_size)
1147 		return NULL;
1148 
1149 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1150 		/* No room for the descriptor in this buffer, so advance to the
1151 		 * next one. */
1152 
1153 		if (desc->list.next == &ctx->buffer_list) {
1154 			/* If there is no free buffer next in the list,
1155 			 * allocate one. */
1156 			if (context_add_buffer(ctx) < 0)
1157 				return NULL;
1158 		}
1159 		desc = list_entry(desc->list.next,
1160 				struct descriptor_buffer, list);
1161 		ctx->buffer_tail = desc;
1162 	}
1163 
1164 	d = desc->buffer + desc->used / sizeof(*d);
1165 	memset(d, 0, z * sizeof(*d));
1166 	*d_bus = desc->buffer_bus + desc->used;
1167 
1168 	return d;
1169 }
1170 
1171 static void context_run(struct context *ctx, u32 extra)
1172 {
1173 	struct fw_ohci *ohci = ctx->ohci;
1174 
1175 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1176 		  le32_to_cpu(ctx->last->branch_address));
1177 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1178 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1179 	ctx->running = true;
1180 	flush_writes(ohci);
1181 }
1182 
1183 static void context_append(struct context *ctx,
1184 			   struct descriptor *d, int z, int extra)
1185 {
1186 	dma_addr_t d_bus;
1187 	struct descriptor_buffer *desc = ctx->buffer_tail;
1188 
1189 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1190 
1191 	desc->used += (z + extra) * sizeof(*d);
1192 
1193 	wmb(); /* finish init of new descriptors before branch_address update */
1194 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1195 	ctx->prev = find_branch_descriptor(d, z);
1196 }
1197 
1198 static void context_stop(struct context *ctx)
1199 {
1200 	u32 reg;
1201 	int i;
1202 
1203 	reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1204 	ctx->running = false;
1205 	flush_writes(ctx->ohci);
1206 
1207 	for (i = 0; i < 10; i++) {
1208 		reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1209 		if ((reg & CONTEXT_ACTIVE) == 0)
1210 			return;
1211 
1212 		mdelay(1);
1213 	}
1214 	fw_error("Error: DMA context still active (0x%08x)\n", reg);
1215 }
1216 
1217 struct driver_data {
1218 	u8 inline_data[8];
1219 	struct fw_packet *packet;
1220 };
1221 
1222 /*
1223  * This function apppends a packet to the DMA queue for transmission.
1224  * Must always be called with the ochi->lock held to ensure proper
1225  * generation handling and locking around packet queue manipulation.
1226  */
1227 static int at_context_queue_packet(struct context *ctx,
1228 				   struct fw_packet *packet)
1229 {
1230 	struct fw_ohci *ohci = ctx->ohci;
1231 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1232 	struct driver_data *driver_data;
1233 	struct descriptor *d, *last;
1234 	__le32 *header;
1235 	int z, tcode;
1236 
1237 	d = context_get_descriptors(ctx, 4, &d_bus);
1238 	if (d == NULL) {
1239 		packet->ack = RCODE_SEND_ERROR;
1240 		return -1;
1241 	}
1242 
1243 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1244 	d[0].res_count = cpu_to_le16(packet->timestamp);
1245 
1246 	/*
1247 	 * The DMA format for asyncronous link packets is different
1248 	 * from the IEEE1394 layout, so shift the fields around
1249 	 * accordingly.
1250 	 */
1251 
1252 	tcode = (packet->header[0] >> 4) & 0x0f;
1253 	header = (__le32 *) &d[1];
1254 	switch (tcode) {
1255 	case TCODE_WRITE_QUADLET_REQUEST:
1256 	case TCODE_WRITE_BLOCK_REQUEST:
1257 	case TCODE_WRITE_RESPONSE:
1258 	case TCODE_READ_QUADLET_REQUEST:
1259 	case TCODE_READ_BLOCK_REQUEST:
1260 	case TCODE_READ_QUADLET_RESPONSE:
1261 	case TCODE_READ_BLOCK_RESPONSE:
1262 	case TCODE_LOCK_REQUEST:
1263 	case TCODE_LOCK_RESPONSE:
1264 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1265 					(packet->speed << 16));
1266 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1267 					(packet->header[0] & 0xffff0000));
1268 		header[2] = cpu_to_le32(packet->header[2]);
1269 
1270 		if (TCODE_IS_BLOCK_PACKET(tcode))
1271 			header[3] = cpu_to_le32(packet->header[3]);
1272 		else
1273 			header[3] = (__force __le32) packet->header[3];
1274 
1275 		d[0].req_count = cpu_to_le16(packet->header_length);
1276 		break;
1277 
1278 	case TCODE_LINK_INTERNAL:
1279 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1280 					(packet->speed << 16));
1281 		header[1] = cpu_to_le32(packet->header[1]);
1282 		header[2] = cpu_to_le32(packet->header[2]);
1283 		d[0].req_count = cpu_to_le16(12);
1284 
1285 		if (is_ping_packet(&packet->header[1]))
1286 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1287 		break;
1288 
1289 	case TCODE_STREAM_DATA:
1290 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1291 					(packet->speed << 16));
1292 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1293 		d[0].req_count = cpu_to_le16(8);
1294 		break;
1295 
1296 	default:
1297 		/* BUG(); */
1298 		packet->ack = RCODE_SEND_ERROR;
1299 		return -1;
1300 	}
1301 
1302 	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1303 	driver_data = (struct driver_data *) &d[3];
1304 	driver_data->packet = packet;
1305 	packet->driver_data = driver_data;
1306 
1307 	if (packet->payload_length > 0) {
1308 		if (packet->payload_length > sizeof(driver_data->inline_data)) {
1309 			payload_bus = dma_map_single(ohci->card.device,
1310 						     packet->payload,
1311 						     packet->payload_length,
1312 						     DMA_TO_DEVICE);
1313 			if (dma_mapping_error(ohci->card.device, payload_bus)) {
1314 				packet->ack = RCODE_SEND_ERROR;
1315 				return -1;
1316 			}
1317 			packet->payload_bus	= payload_bus;
1318 			packet->payload_mapped	= true;
1319 		} else {
1320 			memcpy(driver_data->inline_data, packet->payload,
1321 			       packet->payload_length);
1322 			payload_bus = d_bus + 3 * sizeof(*d);
1323 		}
1324 
1325 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1326 		d[2].data_address = cpu_to_le32(payload_bus);
1327 		last = &d[2];
1328 		z = 3;
1329 	} else {
1330 		last = &d[0];
1331 		z = 2;
1332 	}
1333 
1334 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1335 				     DESCRIPTOR_IRQ_ALWAYS |
1336 				     DESCRIPTOR_BRANCH_ALWAYS);
1337 
1338 	/* FIXME: Document how the locking works. */
1339 	if (ohci->generation != packet->generation) {
1340 		if (packet->payload_mapped)
1341 			dma_unmap_single(ohci->card.device, payload_bus,
1342 					 packet->payload_length, DMA_TO_DEVICE);
1343 		packet->ack = RCODE_GENERATION;
1344 		return -1;
1345 	}
1346 
1347 	context_append(ctx, d, z, 4 - z);
1348 
1349 	if (ctx->running) {
1350 		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1351 		flush_writes(ohci);
1352 	} else {
1353 		context_run(ctx, 0);
1354 	}
1355 
1356 	return 0;
1357 }
1358 
1359 static void at_context_flush(struct context *ctx)
1360 {
1361 	tasklet_disable(&ctx->tasklet);
1362 
1363 	ctx->flushing = true;
1364 	context_tasklet((unsigned long)ctx);
1365 	ctx->flushing = false;
1366 
1367 	tasklet_enable(&ctx->tasklet);
1368 }
1369 
1370 static int handle_at_packet(struct context *context,
1371 			    struct descriptor *d,
1372 			    struct descriptor *last)
1373 {
1374 	struct driver_data *driver_data;
1375 	struct fw_packet *packet;
1376 	struct fw_ohci *ohci = context->ohci;
1377 	int evt;
1378 
1379 	if (last->transfer_status == 0 && !context->flushing)
1380 		/* This descriptor isn't done yet, stop iteration. */
1381 		return 0;
1382 
1383 	driver_data = (struct driver_data *) &d[3];
1384 	packet = driver_data->packet;
1385 	if (packet == NULL)
1386 		/* This packet was cancelled, just continue. */
1387 		return 1;
1388 
1389 	if (packet->payload_mapped)
1390 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1391 				 packet->payload_length, DMA_TO_DEVICE);
1392 
1393 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1394 	packet->timestamp = le16_to_cpu(last->res_count);
1395 
1396 	log_ar_at_event('T', packet->speed, packet->header, evt);
1397 
1398 	switch (evt) {
1399 	case OHCI1394_evt_timeout:
1400 		/* Async response transmit timed out. */
1401 		packet->ack = RCODE_CANCELLED;
1402 		break;
1403 
1404 	case OHCI1394_evt_flushed:
1405 		/*
1406 		 * The packet was flushed should give same error as
1407 		 * when we try to use a stale generation count.
1408 		 */
1409 		packet->ack = RCODE_GENERATION;
1410 		break;
1411 
1412 	case OHCI1394_evt_missing_ack:
1413 		if (context->flushing)
1414 			packet->ack = RCODE_GENERATION;
1415 		else {
1416 			/*
1417 			 * Using a valid (current) generation count, but the
1418 			 * node is not on the bus or not sending acks.
1419 			 */
1420 			packet->ack = RCODE_NO_ACK;
1421 		}
1422 		break;
1423 
1424 	case ACK_COMPLETE + 0x10:
1425 	case ACK_PENDING + 0x10:
1426 	case ACK_BUSY_X + 0x10:
1427 	case ACK_BUSY_A + 0x10:
1428 	case ACK_BUSY_B + 0x10:
1429 	case ACK_DATA_ERROR + 0x10:
1430 	case ACK_TYPE_ERROR + 0x10:
1431 		packet->ack = evt - 0x10;
1432 		break;
1433 
1434 	case OHCI1394_evt_no_status:
1435 		if (context->flushing) {
1436 			packet->ack = RCODE_GENERATION;
1437 			break;
1438 		}
1439 		/* fall through */
1440 
1441 	default:
1442 		packet->ack = RCODE_SEND_ERROR;
1443 		break;
1444 	}
1445 
1446 	packet->callback(packet, &ohci->card, packet->ack);
1447 
1448 	return 1;
1449 }
1450 
1451 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1452 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1453 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1454 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1455 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1456 
1457 static void handle_local_rom(struct fw_ohci *ohci,
1458 			     struct fw_packet *packet, u32 csr)
1459 {
1460 	struct fw_packet response;
1461 	int tcode, length, i;
1462 
1463 	tcode = HEADER_GET_TCODE(packet->header[0]);
1464 	if (TCODE_IS_BLOCK_PACKET(tcode))
1465 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1466 	else
1467 		length = 4;
1468 
1469 	i = csr - CSR_CONFIG_ROM;
1470 	if (i + length > CONFIG_ROM_SIZE) {
1471 		fw_fill_response(&response, packet->header,
1472 				 RCODE_ADDRESS_ERROR, NULL, 0);
1473 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1474 		fw_fill_response(&response, packet->header,
1475 				 RCODE_TYPE_ERROR, NULL, 0);
1476 	} else {
1477 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1478 				 (void *) ohci->config_rom + i, length);
1479 	}
1480 
1481 	fw_core_handle_response(&ohci->card, &response);
1482 }
1483 
1484 static void handle_local_lock(struct fw_ohci *ohci,
1485 			      struct fw_packet *packet, u32 csr)
1486 {
1487 	struct fw_packet response;
1488 	int tcode, length, ext_tcode, sel, try;
1489 	__be32 *payload, lock_old;
1490 	u32 lock_arg, lock_data;
1491 
1492 	tcode = HEADER_GET_TCODE(packet->header[0]);
1493 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1494 	payload = packet->payload;
1495 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1496 
1497 	if (tcode == TCODE_LOCK_REQUEST &&
1498 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1499 		lock_arg = be32_to_cpu(payload[0]);
1500 		lock_data = be32_to_cpu(payload[1]);
1501 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1502 		lock_arg = 0;
1503 		lock_data = 0;
1504 	} else {
1505 		fw_fill_response(&response, packet->header,
1506 				 RCODE_TYPE_ERROR, NULL, 0);
1507 		goto out;
1508 	}
1509 
1510 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1511 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1512 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1513 	reg_write(ohci, OHCI1394_CSRControl, sel);
1514 
1515 	for (try = 0; try < 20; try++)
1516 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1517 			lock_old = cpu_to_be32(reg_read(ohci,
1518 							OHCI1394_CSRData));
1519 			fw_fill_response(&response, packet->header,
1520 					 RCODE_COMPLETE,
1521 					 &lock_old, sizeof(lock_old));
1522 			goto out;
1523 		}
1524 
1525 	fw_error("swap not done (CSR lock timeout)\n");
1526 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1527 
1528  out:
1529 	fw_core_handle_response(&ohci->card, &response);
1530 }
1531 
1532 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1533 {
1534 	u64 offset, csr;
1535 
1536 	if (ctx == &ctx->ohci->at_request_ctx) {
1537 		packet->ack = ACK_PENDING;
1538 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1539 	}
1540 
1541 	offset =
1542 		((unsigned long long)
1543 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1544 		packet->header[2];
1545 	csr = offset - CSR_REGISTER_BASE;
1546 
1547 	/* Handle config rom reads. */
1548 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1549 		handle_local_rom(ctx->ohci, packet, csr);
1550 	else switch (csr) {
1551 	case CSR_BUS_MANAGER_ID:
1552 	case CSR_BANDWIDTH_AVAILABLE:
1553 	case CSR_CHANNELS_AVAILABLE_HI:
1554 	case CSR_CHANNELS_AVAILABLE_LO:
1555 		handle_local_lock(ctx->ohci, packet, csr);
1556 		break;
1557 	default:
1558 		if (ctx == &ctx->ohci->at_request_ctx)
1559 			fw_core_handle_request(&ctx->ohci->card, packet);
1560 		else
1561 			fw_core_handle_response(&ctx->ohci->card, packet);
1562 		break;
1563 	}
1564 
1565 	if (ctx == &ctx->ohci->at_response_ctx) {
1566 		packet->ack = ACK_COMPLETE;
1567 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1568 	}
1569 }
1570 
1571 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1572 {
1573 	unsigned long flags;
1574 	int ret;
1575 
1576 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1577 
1578 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1579 	    ctx->ohci->generation == packet->generation) {
1580 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1581 		handle_local_request(ctx, packet);
1582 		return;
1583 	}
1584 
1585 	ret = at_context_queue_packet(ctx, packet);
1586 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1587 
1588 	if (ret < 0)
1589 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1590 
1591 }
1592 
1593 static void detect_dead_context(struct fw_ohci *ohci,
1594 				const char *name, unsigned int regs)
1595 {
1596 	u32 ctl;
1597 
1598 	ctl = reg_read(ohci, CONTROL_SET(regs));
1599 	if (ctl & CONTEXT_DEAD) {
1600 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
1601 		fw_error("DMA context %s has stopped, error code: %s\n",
1602 			 name, evts[ctl & 0x1f]);
1603 #else
1604 		fw_error("DMA context %s has stopped, error code: %#x\n",
1605 			 name, ctl & 0x1f);
1606 #endif
1607 	}
1608 }
1609 
1610 static void handle_dead_contexts(struct fw_ohci *ohci)
1611 {
1612 	unsigned int i;
1613 	char name[8];
1614 
1615 	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1616 	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1617 	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1618 	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1619 	for (i = 0; i < 32; ++i) {
1620 		if (!(ohci->it_context_support & (1 << i)))
1621 			continue;
1622 		sprintf(name, "IT%u", i);
1623 		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1624 	}
1625 	for (i = 0; i < 32; ++i) {
1626 		if (!(ohci->ir_context_support & (1 << i)))
1627 			continue;
1628 		sprintf(name, "IR%u", i);
1629 		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1630 	}
1631 	/* TODO: maybe try to flush and restart the dead contexts */
1632 }
1633 
1634 static u32 cycle_timer_ticks(u32 cycle_timer)
1635 {
1636 	u32 ticks;
1637 
1638 	ticks = cycle_timer & 0xfff;
1639 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1640 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1641 
1642 	return ticks;
1643 }
1644 
1645 /*
1646  * Some controllers exhibit one or more of the following bugs when updating the
1647  * iso cycle timer register:
1648  *  - When the lowest six bits are wrapping around to zero, a read that happens
1649  *    at the same time will return garbage in the lowest ten bits.
1650  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1651  *    not incremented for about 60 ns.
1652  *  - Occasionally, the entire register reads zero.
1653  *
1654  * To catch these, we read the register three times and ensure that the
1655  * difference between each two consecutive reads is approximately the same, i.e.
1656  * less than twice the other.  Furthermore, any negative difference indicates an
1657  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1658  * execute, so we have enough precision to compute the ratio of the differences.)
1659  */
1660 static u32 get_cycle_time(struct fw_ohci *ohci)
1661 {
1662 	u32 c0, c1, c2;
1663 	u32 t0, t1, t2;
1664 	s32 diff01, diff12;
1665 	int i;
1666 
1667 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1668 
1669 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1670 		i = 0;
1671 		c1 = c2;
1672 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1673 		do {
1674 			c0 = c1;
1675 			c1 = c2;
1676 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1677 			t0 = cycle_timer_ticks(c0);
1678 			t1 = cycle_timer_ticks(c1);
1679 			t2 = cycle_timer_ticks(c2);
1680 			diff01 = t1 - t0;
1681 			diff12 = t2 - t1;
1682 		} while ((diff01 <= 0 || diff12 <= 0 ||
1683 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1684 			 && i++ < 20);
1685 	}
1686 
1687 	return c2;
1688 }
1689 
1690 /*
1691  * This function has to be called at least every 64 seconds.  The bus_time
1692  * field stores not only the upper 25 bits of the BUS_TIME register but also
1693  * the most significant bit of the cycle timer in bit 6 so that we can detect
1694  * changes in this bit.
1695  */
1696 static u32 update_bus_time(struct fw_ohci *ohci)
1697 {
1698 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1699 
1700 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1701 		ohci->bus_time += 0x40;
1702 
1703 	return ohci->bus_time | cycle_time_seconds;
1704 }
1705 
1706 static void bus_reset_tasklet(unsigned long data)
1707 {
1708 	struct fw_ohci *ohci = (struct fw_ohci *)data;
1709 	int self_id_count, i, j, reg;
1710 	int generation, new_generation;
1711 	unsigned long flags;
1712 	void *free_rom = NULL;
1713 	dma_addr_t free_rom_bus = 0;
1714 	bool is_new_root;
1715 
1716 	reg = reg_read(ohci, OHCI1394_NodeID);
1717 	if (!(reg & OHCI1394_NodeID_idValid)) {
1718 		fw_notify("node ID not valid, new bus reset in progress\n");
1719 		return;
1720 	}
1721 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1722 		fw_notify("malconfigured bus\n");
1723 		return;
1724 	}
1725 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1726 			       OHCI1394_NodeID_nodeNumber);
1727 
1728 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1729 	if (!(ohci->is_root && is_new_root))
1730 		reg_write(ohci, OHCI1394_LinkControlSet,
1731 			  OHCI1394_LinkControl_cycleMaster);
1732 	ohci->is_root = is_new_root;
1733 
1734 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1735 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1736 		fw_notify("inconsistent self IDs\n");
1737 		return;
1738 	}
1739 	/*
1740 	 * The count in the SelfIDCount register is the number of
1741 	 * bytes in the self ID receive buffer.  Since we also receive
1742 	 * the inverted quadlets and a header quadlet, we shift one
1743 	 * bit extra to get the actual number of self IDs.
1744 	 */
1745 	self_id_count = (reg >> 3) & 0xff;
1746 	if (self_id_count == 0 || self_id_count > 252) {
1747 		fw_notify("inconsistent self IDs\n");
1748 		return;
1749 	}
1750 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1751 	rmb();
1752 
1753 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1754 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1755 			fw_notify("inconsistent self IDs\n");
1756 			return;
1757 		}
1758 		ohci->self_id_buffer[j] =
1759 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1760 	}
1761 	rmb();
1762 
1763 	/*
1764 	 * Check the consistency of the self IDs we just read.  The
1765 	 * problem we face is that a new bus reset can start while we
1766 	 * read out the self IDs from the DMA buffer. If this happens,
1767 	 * the DMA buffer will be overwritten with new self IDs and we
1768 	 * will read out inconsistent data.  The OHCI specification
1769 	 * (section 11.2) recommends a technique similar to
1770 	 * linux/seqlock.h, where we remember the generation of the
1771 	 * self IDs in the buffer before reading them out and compare
1772 	 * it to the current generation after reading them out.  If
1773 	 * the two generations match we know we have a consistent set
1774 	 * of self IDs.
1775 	 */
1776 
1777 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1778 	if (new_generation != generation) {
1779 		fw_notify("recursive bus reset detected, "
1780 			  "discarding self ids\n");
1781 		return;
1782 	}
1783 
1784 	/* FIXME: Document how the locking works. */
1785 	spin_lock_irqsave(&ohci->lock, flags);
1786 
1787 	ohci->generation = -1; /* prevent AT packet queueing */
1788 	context_stop(&ohci->at_request_ctx);
1789 	context_stop(&ohci->at_response_ctx);
1790 
1791 	spin_unlock_irqrestore(&ohci->lock, flags);
1792 
1793 	/*
1794 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
1795 	 * packets in the AT queues and software needs to drain them.
1796 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
1797 	 */
1798 	at_context_flush(&ohci->at_request_ctx);
1799 	at_context_flush(&ohci->at_response_ctx);
1800 
1801 	spin_lock_irqsave(&ohci->lock, flags);
1802 
1803 	ohci->generation = generation;
1804 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1805 
1806 	if (ohci->quirks & QUIRK_RESET_PACKET)
1807 		ohci->request_generation = generation;
1808 
1809 	/*
1810 	 * This next bit is unrelated to the AT context stuff but we
1811 	 * have to do it under the spinlock also.  If a new config rom
1812 	 * was set up before this reset, the old one is now no longer
1813 	 * in use and we can free it. Update the config rom pointers
1814 	 * to point to the current config rom and clear the
1815 	 * next_config_rom pointer so a new update can take place.
1816 	 */
1817 
1818 	if (ohci->next_config_rom != NULL) {
1819 		if (ohci->next_config_rom != ohci->config_rom) {
1820 			free_rom      = ohci->config_rom;
1821 			free_rom_bus  = ohci->config_rom_bus;
1822 		}
1823 		ohci->config_rom      = ohci->next_config_rom;
1824 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1825 		ohci->next_config_rom = NULL;
1826 
1827 		/*
1828 		 * Restore config_rom image and manually update
1829 		 * config_rom registers.  Writing the header quadlet
1830 		 * will indicate that the config rom is ready, so we
1831 		 * do that last.
1832 		 */
1833 		reg_write(ohci, OHCI1394_BusOptions,
1834 			  be32_to_cpu(ohci->config_rom[2]));
1835 		ohci->config_rom[0] = ohci->next_header;
1836 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1837 			  be32_to_cpu(ohci->next_header));
1838 	}
1839 
1840 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1841 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1842 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1843 #endif
1844 
1845 	spin_unlock_irqrestore(&ohci->lock, flags);
1846 
1847 	if (free_rom)
1848 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1849 				  free_rom, free_rom_bus);
1850 
1851 	log_selfids(ohci->node_id, generation,
1852 		    self_id_count, ohci->self_id_buffer);
1853 
1854 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1855 				 self_id_count, ohci->self_id_buffer,
1856 				 ohci->csr_state_setclear_abdicate);
1857 	ohci->csr_state_setclear_abdicate = false;
1858 }
1859 
1860 static irqreturn_t irq_handler(int irq, void *data)
1861 {
1862 	struct fw_ohci *ohci = data;
1863 	u32 event, iso_event;
1864 	int i;
1865 
1866 	event = reg_read(ohci, OHCI1394_IntEventClear);
1867 
1868 	if (!event || !~event)
1869 		return IRQ_NONE;
1870 
1871 	/*
1872 	 * busReset and postedWriteErr must not be cleared yet
1873 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
1874 	 */
1875 	reg_write(ohci, OHCI1394_IntEventClear,
1876 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
1877 	log_irqs(event);
1878 
1879 	if (event & OHCI1394_selfIDComplete)
1880 		tasklet_schedule(&ohci->bus_reset_tasklet);
1881 
1882 	if (event & OHCI1394_RQPkt)
1883 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1884 
1885 	if (event & OHCI1394_RSPkt)
1886 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1887 
1888 	if (event & OHCI1394_reqTxComplete)
1889 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
1890 
1891 	if (event & OHCI1394_respTxComplete)
1892 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
1893 
1894 	if (event & OHCI1394_isochRx) {
1895 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1896 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1897 
1898 		while (iso_event) {
1899 			i = ffs(iso_event) - 1;
1900 			tasklet_schedule(
1901 				&ohci->ir_context_list[i].context.tasklet);
1902 			iso_event &= ~(1 << i);
1903 		}
1904 	}
1905 
1906 	if (event & OHCI1394_isochTx) {
1907 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1908 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1909 
1910 		while (iso_event) {
1911 			i = ffs(iso_event) - 1;
1912 			tasklet_schedule(
1913 				&ohci->it_context_list[i].context.tasklet);
1914 			iso_event &= ~(1 << i);
1915 		}
1916 	}
1917 
1918 	if (unlikely(event & OHCI1394_regAccessFail))
1919 		fw_error("Register access failure - "
1920 			 "please notify linux1394-devel@lists.sf.net\n");
1921 
1922 	if (unlikely(event & OHCI1394_postedWriteErr)) {
1923 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
1924 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
1925 		reg_write(ohci, OHCI1394_IntEventClear,
1926 			  OHCI1394_postedWriteErr);
1927 		fw_error("PCI posted write error\n");
1928 	}
1929 
1930 	if (unlikely(event & OHCI1394_cycleTooLong)) {
1931 		if (printk_ratelimit())
1932 			fw_notify("isochronous cycle too long\n");
1933 		reg_write(ohci, OHCI1394_LinkControlSet,
1934 			  OHCI1394_LinkControl_cycleMaster);
1935 	}
1936 
1937 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
1938 		/*
1939 		 * We need to clear this event bit in order to make
1940 		 * cycleMatch isochronous I/O work.  In theory we should
1941 		 * stop active cycleMatch iso contexts now and restart
1942 		 * them at least two cycles later.  (FIXME?)
1943 		 */
1944 		if (printk_ratelimit())
1945 			fw_notify("isochronous cycle inconsistent\n");
1946 	}
1947 
1948 	if (unlikely(event & OHCI1394_unrecoverableError))
1949 		handle_dead_contexts(ohci);
1950 
1951 	if (event & OHCI1394_cycle64Seconds) {
1952 		spin_lock(&ohci->lock);
1953 		update_bus_time(ohci);
1954 		spin_unlock(&ohci->lock);
1955 	} else
1956 		flush_writes(ohci);
1957 
1958 	return IRQ_HANDLED;
1959 }
1960 
1961 static int software_reset(struct fw_ohci *ohci)
1962 {
1963 	int i;
1964 
1965 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1966 
1967 	for (i = 0; i < OHCI_LOOP_COUNT; i++) {
1968 		if ((reg_read(ohci, OHCI1394_HCControlSet) &
1969 		     OHCI1394_HCControl_softReset) == 0)
1970 			return 0;
1971 		msleep(1);
1972 	}
1973 
1974 	return -EBUSY;
1975 }
1976 
1977 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
1978 {
1979 	size_t size = length * 4;
1980 
1981 	memcpy(dest, src, size);
1982 	if (size < CONFIG_ROM_SIZE)
1983 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
1984 }
1985 
1986 static int configure_1394a_enhancements(struct fw_ohci *ohci)
1987 {
1988 	bool enable_1394a;
1989 	int ret, clear, set, offset;
1990 
1991 	/* Check if the driver should configure link and PHY. */
1992 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
1993 	      OHCI1394_HCControl_programPhyEnable))
1994 		return 0;
1995 
1996 	/* Paranoia: check whether the PHY supports 1394a, too. */
1997 	enable_1394a = false;
1998 	ret = read_phy_reg(ohci, 2);
1999 	if (ret < 0)
2000 		return ret;
2001 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2002 		ret = read_paged_phy_reg(ohci, 1, 8);
2003 		if (ret < 0)
2004 			return ret;
2005 		if (ret >= 1)
2006 			enable_1394a = true;
2007 	}
2008 
2009 	if (ohci->quirks & QUIRK_NO_1394A)
2010 		enable_1394a = false;
2011 
2012 	/* Configure PHY and link consistently. */
2013 	if (enable_1394a) {
2014 		clear = 0;
2015 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2016 	} else {
2017 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2018 		set = 0;
2019 	}
2020 	ret = update_phy_reg(ohci, 5, clear, set);
2021 	if (ret < 0)
2022 		return ret;
2023 
2024 	if (enable_1394a)
2025 		offset = OHCI1394_HCControlSet;
2026 	else
2027 		offset = OHCI1394_HCControlClear;
2028 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2029 
2030 	/* Clean up: configuration has been taken care of. */
2031 	reg_write(ohci, OHCI1394_HCControlClear,
2032 		  OHCI1394_HCControl_programPhyEnable);
2033 
2034 	return 0;
2035 }
2036 
2037 static int ohci_enable(struct fw_card *card,
2038 		       const __be32 *config_rom, size_t length)
2039 {
2040 	struct fw_ohci *ohci = fw_ohci(card);
2041 	struct pci_dev *dev = to_pci_dev(card->device);
2042 	u32 lps, seconds, version, irqs;
2043 	int i, ret;
2044 
2045 	if (software_reset(ohci)) {
2046 		fw_error("Failed to reset ohci card.\n");
2047 		return -EBUSY;
2048 	}
2049 
2050 	/*
2051 	 * Now enable LPS, which we need in order to start accessing
2052 	 * most of the registers.  In fact, on some cards (ALI M5251),
2053 	 * accessing registers in the SClk domain without LPS enabled
2054 	 * will lock up the machine.  Wait 50msec to make sure we have
2055 	 * full link enabled.  However, with some cards (well, at least
2056 	 * a JMicron PCIe card), we have to try again sometimes.
2057 	 */
2058 	reg_write(ohci, OHCI1394_HCControlSet,
2059 		  OHCI1394_HCControl_LPS |
2060 		  OHCI1394_HCControl_postedWriteEnable);
2061 	flush_writes(ohci);
2062 
2063 	for (lps = 0, i = 0; !lps && i < 3; i++) {
2064 		msleep(50);
2065 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2066 		      OHCI1394_HCControl_LPS;
2067 	}
2068 
2069 	if (!lps) {
2070 		fw_error("Failed to set Link Power Status\n");
2071 		return -EIO;
2072 	}
2073 
2074 	reg_write(ohci, OHCI1394_HCControlClear,
2075 		  OHCI1394_HCControl_noByteSwapData);
2076 
2077 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2078 	reg_write(ohci, OHCI1394_LinkControlSet,
2079 		  OHCI1394_LinkControl_cycleTimerEnable |
2080 		  OHCI1394_LinkControl_cycleMaster);
2081 
2082 	reg_write(ohci, OHCI1394_ATRetries,
2083 		  OHCI1394_MAX_AT_REQ_RETRIES |
2084 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2085 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2086 		  (200 << 16));
2087 
2088 	seconds = lower_32_bits(get_seconds());
2089 	reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
2090 	ohci->bus_time = seconds & ~0x3f;
2091 
2092 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2093 	if (version >= OHCI_VERSION_1_1) {
2094 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2095 			  0xfffffffe);
2096 		card->broadcast_channel_auto_allocated = true;
2097 	}
2098 
2099 	/* Get implemented bits of the priority arbitration request counter. */
2100 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2101 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2102 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2103 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2104 
2105 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
2106 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2107 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2108 
2109 	ret = configure_1394a_enhancements(ohci);
2110 	if (ret < 0)
2111 		return ret;
2112 
2113 	/* Activate link_on bit and contender bit in our self ID packets.*/
2114 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2115 	if (ret < 0)
2116 		return ret;
2117 
2118 	/*
2119 	 * When the link is not yet enabled, the atomic config rom
2120 	 * update mechanism described below in ohci_set_config_rom()
2121 	 * is not active.  We have to update ConfigRomHeader and
2122 	 * BusOptions manually, and the write to ConfigROMmap takes
2123 	 * effect immediately.  We tie this to the enabling of the
2124 	 * link, so we have a valid config rom before enabling - the
2125 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2126 	 * values before enabling.
2127 	 *
2128 	 * However, when the ConfigROMmap is written, some controllers
2129 	 * always read back quadlets 0 and 2 from the config rom to
2130 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2131 	 * They shouldn't do that in this initial case where the link
2132 	 * isn't enabled.  This means we have to use the same
2133 	 * workaround here, setting the bus header to 0 and then write
2134 	 * the right values in the bus reset tasklet.
2135 	 */
2136 
2137 	if (config_rom) {
2138 		ohci->next_config_rom =
2139 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2140 					   &ohci->next_config_rom_bus,
2141 					   GFP_KERNEL);
2142 		if (ohci->next_config_rom == NULL)
2143 			return -ENOMEM;
2144 
2145 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2146 	} else {
2147 		/*
2148 		 * In the suspend case, config_rom is NULL, which
2149 		 * means that we just reuse the old config rom.
2150 		 */
2151 		ohci->next_config_rom = ohci->config_rom;
2152 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2153 	}
2154 
2155 	ohci->next_header = ohci->next_config_rom[0];
2156 	ohci->next_config_rom[0] = 0;
2157 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2158 	reg_write(ohci, OHCI1394_BusOptions,
2159 		  be32_to_cpu(ohci->next_config_rom[2]));
2160 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2161 
2162 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2163 
2164 	if (!(ohci->quirks & QUIRK_NO_MSI))
2165 		pci_enable_msi(dev);
2166 	if (request_irq(dev->irq, irq_handler,
2167 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
2168 			ohci_driver_name, ohci)) {
2169 		fw_error("Failed to allocate interrupt %d.\n", dev->irq);
2170 		pci_disable_msi(dev);
2171 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2172 				  ohci->config_rom, ohci->config_rom_bus);
2173 		return -EIO;
2174 	}
2175 
2176 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2177 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2178 		OHCI1394_isochTx | OHCI1394_isochRx |
2179 		OHCI1394_postedWriteErr |
2180 		OHCI1394_selfIDComplete |
2181 		OHCI1394_regAccessFail |
2182 		OHCI1394_cycle64Seconds |
2183 		OHCI1394_cycleInconsistent |
2184 		OHCI1394_unrecoverableError |
2185 		OHCI1394_cycleTooLong |
2186 		OHCI1394_masterIntEnable;
2187 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2188 		irqs |= OHCI1394_busReset;
2189 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2190 
2191 	reg_write(ohci, OHCI1394_HCControlSet,
2192 		  OHCI1394_HCControl_linkEnable |
2193 		  OHCI1394_HCControl_BIBimageValid);
2194 
2195 	reg_write(ohci, OHCI1394_LinkControlSet,
2196 		  OHCI1394_LinkControl_rcvSelfID |
2197 		  OHCI1394_LinkControl_rcvPhyPkt);
2198 
2199 	ar_context_run(&ohci->ar_request_ctx);
2200 	ar_context_run(&ohci->ar_response_ctx); /* also flushes writes */
2201 
2202 	/* We are ready to go, reset bus to finish initialization. */
2203 	fw_schedule_bus_reset(&ohci->card, false, true);
2204 
2205 	return 0;
2206 }
2207 
2208 static int ohci_set_config_rom(struct fw_card *card,
2209 			       const __be32 *config_rom, size_t length)
2210 {
2211 	struct fw_ohci *ohci;
2212 	unsigned long flags;
2213 	__be32 *next_config_rom;
2214 	dma_addr_t uninitialized_var(next_config_rom_bus);
2215 
2216 	ohci = fw_ohci(card);
2217 
2218 	/*
2219 	 * When the OHCI controller is enabled, the config rom update
2220 	 * mechanism is a bit tricky, but easy enough to use.  See
2221 	 * section 5.5.6 in the OHCI specification.
2222 	 *
2223 	 * The OHCI controller caches the new config rom address in a
2224 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2225 	 * for the changes to take place.  When the bus reset is
2226 	 * detected, the controller loads the new values for the
2227 	 * ConfigRomHeader and BusOptions registers from the specified
2228 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2229 	 * shadow register. All automatically and atomically.
2230 	 *
2231 	 * Now, there's a twist to this story.  The automatic load of
2232 	 * ConfigRomHeader and BusOptions doesn't honor the
2233 	 * noByteSwapData bit, so with a be32 config rom, the
2234 	 * controller will load be32 values in to these registers
2235 	 * during the atomic update, even on litte endian
2236 	 * architectures.  The workaround we use is to put a 0 in the
2237 	 * header quadlet; 0 is endian agnostic and means that the
2238 	 * config rom isn't ready yet.  In the bus reset tasklet we
2239 	 * then set up the real values for the two registers.
2240 	 *
2241 	 * We use ohci->lock to avoid racing with the code that sets
2242 	 * ohci->next_config_rom to NULL (see bus_reset_tasklet).
2243 	 */
2244 
2245 	next_config_rom =
2246 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2247 				   &next_config_rom_bus, GFP_KERNEL);
2248 	if (next_config_rom == NULL)
2249 		return -ENOMEM;
2250 
2251 	spin_lock_irqsave(&ohci->lock, flags);
2252 
2253 	/*
2254 	 * If there is not an already pending config_rom update,
2255 	 * push our new allocation into the ohci->next_config_rom
2256 	 * and then mark the local variable as null so that we
2257 	 * won't deallocate the new buffer.
2258 	 *
2259 	 * OTOH, if there is a pending config_rom update, just
2260 	 * use that buffer with the new config_rom data, and
2261 	 * let this routine free the unused DMA allocation.
2262 	 */
2263 
2264 	if (ohci->next_config_rom == NULL) {
2265 		ohci->next_config_rom = next_config_rom;
2266 		ohci->next_config_rom_bus = next_config_rom_bus;
2267 		next_config_rom = NULL;
2268 	}
2269 
2270 	copy_config_rom(ohci->next_config_rom, config_rom, length);
2271 
2272 	ohci->next_header = config_rom[0];
2273 	ohci->next_config_rom[0] = 0;
2274 
2275 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2276 
2277 	spin_unlock_irqrestore(&ohci->lock, flags);
2278 
2279 	/* If we didn't use the DMA allocation, delete it. */
2280 	if (next_config_rom != NULL)
2281 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2282 				  next_config_rom, next_config_rom_bus);
2283 
2284 	/*
2285 	 * Now initiate a bus reset to have the changes take
2286 	 * effect. We clean up the old config rom memory and DMA
2287 	 * mappings in the bus reset tasklet, since the OHCI
2288 	 * controller could need to access it before the bus reset
2289 	 * takes effect.
2290 	 */
2291 
2292 	fw_schedule_bus_reset(&ohci->card, true, true);
2293 
2294 	return 0;
2295 }
2296 
2297 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2298 {
2299 	struct fw_ohci *ohci = fw_ohci(card);
2300 
2301 	at_context_transmit(&ohci->at_request_ctx, packet);
2302 }
2303 
2304 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2305 {
2306 	struct fw_ohci *ohci = fw_ohci(card);
2307 
2308 	at_context_transmit(&ohci->at_response_ctx, packet);
2309 }
2310 
2311 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2312 {
2313 	struct fw_ohci *ohci = fw_ohci(card);
2314 	struct context *ctx = &ohci->at_request_ctx;
2315 	struct driver_data *driver_data = packet->driver_data;
2316 	int ret = -ENOENT;
2317 
2318 	tasklet_disable(&ctx->tasklet);
2319 
2320 	if (packet->ack != 0)
2321 		goto out;
2322 
2323 	if (packet->payload_mapped)
2324 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2325 				 packet->payload_length, DMA_TO_DEVICE);
2326 
2327 	log_ar_at_event('T', packet->speed, packet->header, 0x20);
2328 	driver_data->packet = NULL;
2329 	packet->ack = RCODE_CANCELLED;
2330 	packet->callback(packet, &ohci->card, packet->ack);
2331 	ret = 0;
2332  out:
2333 	tasklet_enable(&ctx->tasklet);
2334 
2335 	return ret;
2336 }
2337 
2338 static int ohci_enable_phys_dma(struct fw_card *card,
2339 				int node_id, int generation)
2340 {
2341 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2342 	return 0;
2343 #else
2344 	struct fw_ohci *ohci = fw_ohci(card);
2345 	unsigned long flags;
2346 	int n, ret = 0;
2347 
2348 	/*
2349 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2350 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2351 	 */
2352 
2353 	spin_lock_irqsave(&ohci->lock, flags);
2354 
2355 	if (ohci->generation != generation) {
2356 		ret = -ESTALE;
2357 		goto out;
2358 	}
2359 
2360 	/*
2361 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2362 	 * enabled for _all_ nodes on remote buses.
2363 	 */
2364 
2365 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2366 	if (n < 32)
2367 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2368 	else
2369 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2370 
2371 	flush_writes(ohci);
2372  out:
2373 	spin_unlock_irqrestore(&ohci->lock, flags);
2374 
2375 	return ret;
2376 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2377 }
2378 
2379 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2380 {
2381 	struct fw_ohci *ohci = fw_ohci(card);
2382 	unsigned long flags;
2383 	u32 value;
2384 
2385 	switch (csr_offset) {
2386 	case CSR_STATE_CLEAR:
2387 	case CSR_STATE_SET:
2388 		if (ohci->is_root &&
2389 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2390 		     OHCI1394_LinkControl_cycleMaster))
2391 			value = CSR_STATE_BIT_CMSTR;
2392 		else
2393 			value = 0;
2394 		if (ohci->csr_state_setclear_abdicate)
2395 			value |= CSR_STATE_BIT_ABDICATE;
2396 
2397 		return value;
2398 
2399 	case CSR_NODE_IDS:
2400 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2401 
2402 	case CSR_CYCLE_TIME:
2403 		return get_cycle_time(ohci);
2404 
2405 	case CSR_BUS_TIME:
2406 		/*
2407 		 * We might be called just after the cycle timer has wrapped
2408 		 * around but just before the cycle64Seconds handler, so we
2409 		 * better check here, too, if the bus time needs to be updated.
2410 		 */
2411 		spin_lock_irqsave(&ohci->lock, flags);
2412 		value = update_bus_time(ohci);
2413 		spin_unlock_irqrestore(&ohci->lock, flags);
2414 		return value;
2415 
2416 	case CSR_BUSY_TIMEOUT:
2417 		value = reg_read(ohci, OHCI1394_ATRetries);
2418 		return (value >> 4) & 0x0ffff00f;
2419 
2420 	case CSR_PRIORITY_BUDGET:
2421 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2422 			(ohci->pri_req_max << 8);
2423 
2424 	default:
2425 		WARN_ON(1);
2426 		return 0;
2427 	}
2428 }
2429 
2430 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2431 {
2432 	struct fw_ohci *ohci = fw_ohci(card);
2433 	unsigned long flags;
2434 
2435 	switch (csr_offset) {
2436 	case CSR_STATE_CLEAR:
2437 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2438 			reg_write(ohci, OHCI1394_LinkControlClear,
2439 				  OHCI1394_LinkControl_cycleMaster);
2440 			flush_writes(ohci);
2441 		}
2442 		if (value & CSR_STATE_BIT_ABDICATE)
2443 			ohci->csr_state_setclear_abdicate = false;
2444 		break;
2445 
2446 	case CSR_STATE_SET:
2447 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2448 			reg_write(ohci, OHCI1394_LinkControlSet,
2449 				  OHCI1394_LinkControl_cycleMaster);
2450 			flush_writes(ohci);
2451 		}
2452 		if (value & CSR_STATE_BIT_ABDICATE)
2453 			ohci->csr_state_setclear_abdicate = true;
2454 		break;
2455 
2456 	case CSR_NODE_IDS:
2457 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2458 		flush_writes(ohci);
2459 		break;
2460 
2461 	case CSR_CYCLE_TIME:
2462 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2463 		reg_write(ohci, OHCI1394_IntEventSet,
2464 			  OHCI1394_cycleInconsistent);
2465 		flush_writes(ohci);
2466 		break;
2467 
2468 	case CSR_BUS_TIME:
2469 		spin_lock_irqsave(&ohci->lock, flags);
2470 		ohci->bus_time = (ohci->bus_time & 0x7f) | (value & ~0x7f);
2471 		spin_unlock_irqrestore(&ohci->lock, flags);
2472 		break;
2473 
2474 	case CSR_BUSY_TIMEOUT:
2475 		value = (value & 0xf) | ((value & 0xf) << 4) |
2476 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2477 		reg_write(ohci, OHCI1394_ATRetries, value);
2478 		flush_writes(ohci);
2479 		break;
2480 
2481 	case CSR_PRIORITY_BUDGET:
2482 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2483 		flush_writes(ohci);
2484 		break;
2485 
2486 	default:
2487 		WARN_ON(1);
2488 		break;
2489 	}
2490 }
2491 
2492 static void copy_iso_headers(struct iso_context *ctx, void *p)
2493 {
2494 	int i = ctx->header_length;
2495 
2496 	if (i + ctx->base.header_size > PAGE_SIZE)
2497 		return;
2498 
2499 	/*
2500 	 * The iso header is byteswapped to little endian by
2501 	 * the controller, but the remaining header quadlets
2502 	 * are big endian.  We want to present all the headers
2503 	 * as big endian, so we have to swap the first quadlet.
2504 	 */
2505 	if (ctx->base.header_size > 0)
2506 		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
2507 	if (ctx->base.header_size > 4)
2508 		*(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
2509 	if (ctx->base.header_size > 8)
2510 		memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
2511 	ctx->header_length += ctx->base.header_size;
2512 }
2513 
2514 static int handle_ir_packet_per_buffer(struct context *context,
2515 				       struct descriptor *d,
2516 				       struct descriptor *last)
2517 {
2518 	struct iso_context *ctx =
2519 		container_of(context, struct iso_context, context);
2520 	struct descriptor *pd;
2521 	__le32 *ir_header;
2522 	void *p;
2523 
2524 	for (pd = d; pd <= last; pd++)
2525 		if (pd->transfer_status)
2526 			break;
2527 	if (pd > last)
2528 		/* Descriptor(s) not done yet, stop iteration */
2529 		return 0;
2530 
2531 	p = last + 1;
2532 	copy_iso_headers(ctx, p);
2533 
2534 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2535 		ir_header = (__le32 *) p;
2536 		ctx->base.callback.sc(&ctx->base,
2537 				      le32_to_cpu(ir_header[0]) & 0xffff,
2538 				      ctx->header_length, ctx->header,
2539 				      ctx->base.callback_data);
2540 		ctx->header_length = 0;
2541 	}
2542 
2543 	return 1;
2544 }
2545 
2546 /* d == last because each descriptor block is only a single descriptor. */
2547 static int handle_ir_buffer_fill(struct context *context,
2548 				 struct descriptor *d,
2549 				 struct descriptor *last)
2550 {
2551 	struct iso_context *ctx =
2552 		container_of(context, struct iso_context, context);
2553 
2554 	if (!last->transfer_status)
2555 		/* Descriptor(s) not done yet, stop iteration */
2556 		return 0;
2557 
2558 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS)
2559 		ctx->base.callback.mc(&ctx->base,
2560 				      le32_to_cpu(last->data_address) +
2561 				      le16_to_cpu(last->req_count) -
2562 				      le16_to_cpu(last->res_count),
2563 				      ctx->base.callback_data);
2564 
2565 	return 1;
2566 }
2567 
2568 static int handle_it_packet(struct context *context,
2569 			    struct descriptor *d,
2570 			    struct descriptor *last)
2571 {
2572 	struct iso_context *ctx =
2573 		container_of(context, struct iso_context, context);
2574 	int i;
2575 	struct descriptor *pd;
2576 
2577 	for (pd = d; pd <= last; pd++)
2578 		if (pd->transfer_status)
2579 			break;
2580 	if (pd > last)
2581 		/* Descriptor(s) not done yet, stop iteration */
2582 		return 0;
2583 
2584 	i = ctx->header_length;
2585 	if (i + 4 < PAGE_SIZE) {
2586 		/* Present this value as big-endian to match the receive code */
2587 		*(__be32 *)(ctx->header + i) = cpu_to_be32(
2588 				((u32)le16_to_cpu(pd->transfer_status) << 16) |
2589 				le16_to_cpu(pd->res_count));
2590 		ctx->header_length += 4;
2591 	}
2592 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2593 		ctx->base.callback.sc(&ctx->base, le16_to_cpu(last->res_count),
2594 				      ctx->header_length, ctx->header,
2595 				      ctx->base.callback_data);
2596 		ctx->header_length = 0;
2597 	}
2598 	return 1;
2599 }
2600 
2601 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2602 {
2603 	u32 hi = channels >> 32, lo = channels;
2604 
2605 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2606 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2607 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2608 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2609 	mmiowb();
2610 	ohci->mc_channels = channels;
2611 }
2612 
2613 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2614 				int type, int channel, size_t header_size)
2615 {
2616 	struct fw_ohci *ohci = fw_ohci(card);
2617 	struct iso_context *uninitialized_var(ctx);
2618 	descriptor_callback_t uninitialized_var(callback);
2619 	u64 *uninitialized_var(channels);
2620 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2621 	unsigned long flags;
2622 	int index, ret = -EBUSY;
2623 
2624 	spin_lock_irqsave(&ohci->lock, flags);
2625 
2626 	switch (type) {
2627 	case FW_ISO_CONTEXT_TRANSMIT:
2628 		mask     = &ohci->it_context_mask;
2629 		callback = handle_it_packet;
2630 		index    = ffs(*mask) - 1;
2631 		if (index >= 0) {
2632 			*mask &= ~(1 << index);
2633 			regs = OHCI1394_IsoXmitContextBase(index);
2634 			ctx  = &ohci->it_context_list[index];
2635 		}
2636 		break;
2637 
2638 	case FW_ISO_CONTEXT_RECEIVE:
2639 		channels = &ohci->ir_context_channels;
2640 		mask     = &ohci->ir_context_mask;
2641 		callback = handle_ir_packet_per_buffer;
2642 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2643 		if (index >= 0) {
2644 			*channels &= ~(1ULL << channel);
2645 			*mask     &= ~(1 << index);
2646 			regs = OHCI1394_IsoRcvContextBase(index);
2647 			ctx  = &ohci->ir_context_list[index];
2648 		}
2649 		break;
2650 
2651 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2652 		mask     = &ohci->ir_context_mask;
2653 		callback = handle_ir_buffer_fill;
2654 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2655 		if (index >= 0) {
2656 			ohci->mc_allocated = true;
2657 			*mask &= ~(1 << index);
2658 			regs = OHCI1394_IsoRcvContextBase(index);
2659 			ctx  = &ohci->ir_context_list[index];
2660 		}
2661 		break;
2662 
2663 	default:
2664 		index = -1;
2665 		ret = -ENOSYS;
2666 	}
2667 
2668 	spin_unlock_irqrestore(&ohci->lock, flags);
2669 
2670 	if (index < 0)
2671 		return ERR_PTR(ret);
2672 
2673 	memset(ctx, 0, sizeof(*ctx));
2674 	ctx->header_length = 0;
2675 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2676 	if (ctx->header == NULL) {
2677 		ret = -ENOMEM;
2678 		goto out;
2679 	}
2680 	ret = context_init(&ctx->context, ohci, regs, callback);
2681 	if (ret < 0)
2682 		goto out_with_header;
2683 
2684 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
2685 		set_multichannel_mask(ohci, 0);
2686 
2687 	return &ctx->base;
2688 
2689  out_with_header:
2690 	free_page((unsigned long)ctx->header);
2691  out:
2692 	spin_lock_irqsave(&ohci->lock, flags);
2693 
2694 	switch (type) {
2695 	case FW_ISO_CONTEXT_RECEIVE:
2696 		*channels |= 1ULL << channel;
2697 		break;
2698 
2699 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2700 		ohci->mc_allocated = false;
2701 		break;
2702 	}
2703 	*mask |= 1 << index;
2704 
2705 	spin_unlock_irqrestore(&ohci->lock, flags);
2706 
2707 	return ERR_PTR(ret);
2708 }
2709 
2710 static int ohci_start_iso(struct fw_iso_context *base,
2711 			  s32 cycle, u32 sync, u32 tags)
2712 {
2713 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2714 	struct fw_ohci *ohci = ctx->context.ohci;
2715 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2716 	int index;
2717 
2718 	/* the controller cannot start without any queued packets */
2719 	if (ctx->context.last->branch_address == 0)
2720 		return -ENODATA;
2721 
2722 	switch (ctx->base.type) {
2723 	case FW_ISO_CONTEXT_TRANSMIT:
2724 		index = ctx - ohci->it_context_list;
2725 		match = 0;
2726 		if (cycle >= 0)
2727 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
2728 				(cycle & 0x7fff) << 16;
2729 
2730 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
2731 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
2732 		context_run(&ctx->context, match);
2733 		break;
2734 
2735 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2736 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
2737 		/* fall through */
2738 	case FW_ISO_CONTEXT_RECEIVE:
2739 		index = ctx - ohci->ir_context_list;
2740 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
2741 		if (cycle >= 0) {
2742 			match |= (cycle & 0x07fff) << 12;
2743 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
2744 		}
2745 
2746 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2747 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2748 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2749 		context_run(&ctx->context, control);
2750 
2751 		ctx->sync = sync;
2752 		ctx->tags = tags;
2753 
2754 		break;
2755 	}
2756 
2757 	return 0;
2758 }
2759 
2760 static int ohci_stop_iso(struct fw_iso_context *base)
2761 {
2762 	struct fw_ohci *ohci = fw_ohci(base->card);
2763 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2764 	int index;
2765 
2766 	switch (ctx->base.type) {
2767 	case FW_ISO_CONTEXT_TRANSMIT:
2768 		index = ctx - ohci->it_context_list;
2769 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2770 		break;
2771 
2772 	case FW_ISO_CONTEXT_RECEIVE:
2773 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2774 		index = ctx - ohci->ir_context_list;
2775 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2776 		break;
2777 	}
2778 	flush_writes(ohci);
2779 	context_stop(&ctx->context);
2780 	tasklet_kill(&ctx->context.tasklet);
2781 
2782 	return 0;
2783 }
2784 
2785 static void ohci_free_iso_context(struct fw_iso_context *base)
2786 {
2787 	struct fw_ohci *ohci = fw_ohci(base->card);
2788 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2789 	unsigned long flags;
2790 	int index;
2791 
2792 	ohci_stop_iso(base);
2793 	context_release(&ctx->context);
2794 	free_page((unsigned long)ctx->header);
2795 
2796 	spin_lock_irqsave(&ohci->lock, flags);
2797 
2798 	switch (base->type) {
2799 	case FW_ISO_CONTEXT_TRANSMIT:
2800 		index = ctx - ohci->it_context_list;
2801 		ohci->it_context_mask |= 1 << index;
2802 		break;
2803 
2804 	case FW_ISO_CONTEXT_RECEIVE:
2805 		index = ctx - ohci->ir_context_list;
2806 		ohci->ir_context_mask |= 1 << index;
2807 		ohci->ir_context_channels |= 1ULL << base->channel;
2808 		break;
2809 
2810 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2811 		index = ctx - ohci->ir_context_list;
2812 		ohci->ir_context_mask |= 1 << index;
2813 		ohci->ir_context_channels |= ohci->mc_channels;
2814 		ohci->mc_channels = 0;
2815 		ohci->mc_allocated = false;
2816 		break;
2817 	}
2818 
2819 	spin_unlock_irqrestore(&ohci->lock, flags);
2820 }
2821 
2822 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
2823 {
2824 	struct fw_ohci *ohci = fw_ohci(base->card);
2825 	unsigned long flags;
2826 	int ret;
2827 
2828 	switch (base->type) {
2829 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2830 
2831 		spin_lock_irqsave(&ohci->lock, flags);
2832 
2833 		/* Don't allow multichannel to grab other contexts' channels. */
2834 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
2835 			*channels = ohci->ir_context_channels;
2836 			ret = -EBUSY;
2837 		} else {
2838 			set_multichannel_mask(ohci, *channels);
2839 			ret = 0;
2840 		}
2841 
2842 		spin_unlock_irqrestore(&ohci->lock, flags);
2843 
2844 		break;
2845 	default:
2846 		ret = -EINVAL;
2847 	}
2848 
2849 	return ret;
2850 }
2851 
2852 #ifdef CONFIG_PM
2853 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
2854 {
2855 	int i;
2856 	struct iso_context *ctx;
2857 
2858 	for (i = 0 ; i < ohci->n_ir ; i++) {
2859 		ctx = &ohci->ir_context_list[i];
2860 		if (ctx->context.running)
2861 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
2862 	}
2863 
2864 	for (i = 0 ; i < ohci->n_it ; i++) {
2865 		ctx = &ohci->it_context_list[i];
2866 		if (ctx->context.running)
2867 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
2868 	}
2869 }
2870 #endif
2871 
2872 static int queue_iso_transmit(struct iso_context *ctx,
2873 			      struct fw_iso_packet *packet,
2874 			      struct fw_iso_buffer *buffer,
2875 			      unsigned long payload)
2876 {
2877 	struct descriptor *d, *last, *pd;
2878 	struct fw_iso_packet *p;
2879 	__le32 *header;
2880 	dma_addr_t d_bus, page_bus;
2881 	u32 z, header_z, payload_z, irq;
2882 	u32 payload_index, payload_end_index, next_page_index;
2883 	int page, end_page, i, length, offset;
2884 
2885 	p = packet;
2886 	payload_index = payload;
2887 
2888 	if (p->skip)
2889 		z = 1;
2890 	else
2891 		z = 2;
2892 	if (p->header_length > 0)
2893 		z++;
2894 
2895 	/* Determine the first page the payload isn't contained in. */
2896 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2897 	if (p->payload_length > 0)
2898 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
2899 	else
2900 		payload_z = 0;
2901 
2902 	z += payload_z;
2903 
2904 	/* Get header size in number of descriptors. */
2905 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2906 
2907 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2908 	if (d == NULL)
2909 		return -ENOMEM;
2910 
2911 	if (!p->skip) {
2912 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2913 		d[0].req_count = cpu_to_le16(8);
2914 		/*
2915 		 * Link the skip address to this descriptor itself.  This causes
2916 		 * a context to skip a cycle whenever lost cycles or FIFO
2917 		 * overruns occur, without dropping the data.  The application
2918 		 * should then decide whether this is an error condition or not.
2919 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
2920 		 */
2921 		d[0].branch_address = cpu_to_le32(d_bus | z);
2922 
2923 		header = (__le32 *) &d[1];
2924 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2925 					IT_HEADER_TAG(p->tag) |
2926 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2927 					IT_HEADER_CHANNEL(ctx->base.channel) |
2928 					IT_HEADER_SPEED(ctx->base.speed));
2929 		header[1] =
2930 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2931 							  p->payload_length));
2932 	}
2933 
2934 	if (p->header_length > 0) {
2935 		d[2].req_count    = cpu_to_le16(p->header_length);
2936 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2937 		memcpy(&d[z], p->header, p->header_length);
2938 	}
2939 
2940 	pd = d + z - payload_z;
2941 	payload_end_index = payload_index + p->payload_length;
2942 	for (i = 0; i < payload_z; i++) {
2943 		page               = payload_index >> PAGE_SHIFT;
2944 		offset             = payload_index & ~PAGE_MASK;
2945 		next_page_index    = (page + 1) << PAGE_SHIFT;
2946 		length             =
2947 			min(next_page_index, payload_end_index) - payload_index;
2948 		pd[i].req_count    = cpu_to_le16(length);
2949 
2950 		page_bus = page_private(buffer->pages[page]);
2951 		pd[i].data_address = cpu_to_le32(page_bus + offset);
2952 
2953 		payload_index += length;
2954 	}
2955 
2956 	if (p->interrupt)
2957 		irq = DESCRIPTOR_IRQ_ALWAYS;
2958 	else
2959 		irq = DESCRIPTOR_NO_IRQ;
2960 
2961 	last = z == 2 ? d : d + z - 1;
2962 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2963 				     DESCRIPTOR_STATUS |
2964 				     DESCRIPTOR_BRANCH_ALWAYS |
2965 				     irq);
2966 
2967 	context_append(&ctx->context, d, z, header_z);
2968 
2969 	return 0;
2970 }
2971 
2972 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
2973 				       struct fw_iso_packet *packet,
2974 				       struct fw_iso_buffer *buffer,
2975 				       unsigned long payload)
2976 {
2977 	struct descriptor *d, *pd;
2978 	dma_addr_t d_bus, page_bus;
2979 	u32 z, header_z, rest;
2980 	int i, j, length;
2981 	int page, offset, packet_count, header_size, payload_per_buffer;
2982 
2983 	/*
2984 	 * The OHCI controller puts the isochronous header and trailer in the
2985 	 * buffer, so we need at least 8 bytes.
2986 	 */
2987 	packet_count = packet->header_length / ctx->base.header_size;
2988 	header_size  = max(ctx->base.header_size, (size_t)8);
2989 
2990 	/* Get header size in number of descriptors. */
2991 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2992 	page     = payload >> PAGE_SHIFT;
2993 	offset   = payload & ~PAGE_MASK;
2994 	payload_per_buffer = packet->payload_length / packet_count;
2995 
2996 	for (i = 0; i < packet_count; i++) {
2997 		/* d points to the header descriptor */
2998 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
2999 		d = context_get_descriptors(&ctx->context,
3000 				z + header_z, &d_bus);
3001 		if (d == NULL)
3002 			return -ENOMEM;
3003 
3004 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3005 					      DESCRIPTOR_INPUT_MORE);
3006 		if (packet->skip && i == 0)
3007 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3008 		d->req_count    = cpu_to_le16(header_size);
3009 		d->res_count    = d->req_count;
3010 		d->transfer_status = 0;
3011 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3012 
3013 		rest = payload_per_buffer;
3014 		pd = d;
3015 		for (j = 1; j < z; j++) {
3016 			pd++;
3017 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3018 						  DESCRIPTOR_INPUT_MORE);
3019 
3020 			if (offset + rest < PAGE_SIZE)
3021 				length = rest;
3022 			else
3023 				length = PAGE_SIZE - offset;
3024 			pd->req_count = cpu_to_le16(length);
3025 			pd->res_count = pd->req_count;
3026 			pd->transfer_status = 0;
3027 
3028 			page_bus = page_private(buffer->pages[page]);
3029 			pd->data_address = cpu_to_le32(page_bus + offset);
3030 
3031 			offset = (offset + length) & ~PAGE_MASK;
3032 			rest -= length;
3033 			if (offset == 0)
3034 				page++;
3035 		}
3036 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3037 					  DESCRIPTOR_INPUT_LAST |
3038 					  DESCRIPTOR_BRANCH_ALWAYS);
3039 		if (packet->interrupt && i == packet_count - 1)
3040 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3041 
3042 		context_append(&ctx->context, d, z, header_z);
3043 	}
3044 
3045 	return 0;
3046 }
3047 
3048 static int queue_iso_buffer_fill(struct iso_context *ctx,
3049 				 struct fw_iso_packet *packet,
3050 				 struct fw_iso_buffer *buffer,
3051 				 unsigned long payload)
3052 {
3053 	struct descriptor *d;
3054 	dma_addr_t d_bus, page_bus;
3055 	int page, offset, rest, z, i, length;
3056 
3057 	page   = payload >> PAGE_SHIFT;
3058 	offset = payload & ~PAGE_MASK;
3059 	rest   = packet->payload_length;
3060 
3061 	/* We need one descriptor for each page in the buffer. */
3062 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3063 
3064 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3065 		return -EFAULT;
3066 
3067 	for (i = 0; i < z; i++) {
3068 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3069 		if (d == NULL)
3070 			return -ENOMEM;
3071 
3072 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3073 					 DESCRIPTOR_BRANCH_ALWAYS);
3074 		if (packet->skip && i == 0)
3075 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3076 		if (packet->interrupt && i == z - 1)
3077 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3078 
3079 		if (offset + rest < PAGE_SIZE)
3080 			length = rest;
3081 		else
3082 			length = PAGE_SIZE - offset;
3083 		d->req_count = cpu_to_le16(length);
3084 		d->res_count = d->req_count;
3085 		d->transfer_status = 0;
3086 
3087 		page_bus = page_private(buffer->pages[page]);
3088 		d->data_address = cpu_to_le32(page_bus + offset);
3089 
3090 		rest -= length;
3091 		offset = 0;
3092 		page++;
3093 
3094 		context_append(&ctx->context, d, 1, 0);
3095 	}
3096 
3097 	return 0;
3098 }
3099 
3100 static int ohci_queue_iso(struct fw_iso_context *base,
3101 			  struct fw_iso_packet *packet,
3102 			  struct fw_iso_buffer *buffer,
3103 			  unsigned long payload)
3104 {
3105 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3106 	unsigned long flags;
3107 	int ret = -ENOSYS;
3108 
3109 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3110 	switch (base->type) {
3111 	case FW_ISO_CONTEXT_TRANSMIT:
3112 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
3113 		break;
3114 	case FW_ISO_CONTEXT_RECEIVE:
3115 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3116 		break;
3117 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3118 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3119 		break;
3120 	}
3121 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3122 
3123 	return ret;
3124 }
3125 
3126 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3127 {
3128 	struct context *ctx =
3129 			&container_of(base, struct iso_context, base)->context;
3130 
3131 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3132 	flush_writes(ctx->ohci);
3133 }
3134 
3135 static const struct fw_card_driver ohci_driver = {
3136 	.enable			= ohci_enable,
3137 	.read_phy_reg		= ohci_read_phy_reg,
3138 	.update_phy_reg		= ohci_update_phy_reg,
3139 	.set_config_rom		= ohci_set_config_rom,
3140 	.send_request		= ohci_send_request,
3141 	.send_response		= ohci_send_response,
3142 	.cancel_packet		= ohci_cancel_packet,
3143 	.enable_phys_dma	= ohci_enable_phys_dma,
3144 	.read_csr		= ohci_read_csr,
3145 	.write_csr		= ohci_write_csr,
3146 
3147 	.allocate_iso_context	= ohci_allocate_iso_context,
3148 	.free_iso_context	= ohci_free_iso_context,
3149 	.set_iso_channels	= ohci_set_iso_channels,
3150 	.queue_iso		= ohci_queue_iso,
3151 	.flush_queue_iso	= ohci_flush_queue_iso,
3152 	.start_iso		= ohci_start_iso,
3153 	.stop_iso		= ohci_stop_iso,
3154 };
3155 
3156 #ifdef CONFIG_PPC_PMAC
3157 static void pmac_ohci_on(struct pci_dev *dev)
3158 {
3159 	if (machine_is(powermac)) {
3160 		struct device_node *ofn = pci_device_to_OF_node(dev);
3161 
3162 		if (ofn) {
3163 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3164 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3165 		}
3166 	}
3167 }
3168 
3169 static void pmac_ohci_off(struct pci_dev *dev)
3170 {
3171 	if (machine_is(powermac)) {
3172 		struct device_node *ofn = pci_device_to_OF_node(dev);
3173 
3174 		if (ofn) {
3175 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3176 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3177 		}
3178 	}
3179 }
3180 #else
3181 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3182 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3183 #endif /* CONFIG_PPC_PMAC */
3184 
3185 static int __devinit pci_probe(struct pci_dev *dev,
3186 			       const struct pci_device_id *ent)
3187 {
3188 	struct fw_ohci *ohci;
3189 	u32 bus_options, max_receive, link_speed, version;
3190 	u64 guid;
3191 	int i, err;
3192 	size_t size;
3193 
3194 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3195 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3196 		return -ENOSYS;
3197 	}
3198 
3199 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3200 	if (ohci == NULL) {
3201 		err = -ENOMEM;
3202 		goto fail;
3203 	}
3204 
3205 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3206 
3207 	pmac_ohci_on(dev);
3208 
3209 	err = pci_enable_device(dev);
3210 	if (err) {
3211 		fw_error("Failed to enable OHCI hardware\n");
3212 		goto fail_free;
3213 	}
3214 
3215 	pci_set_master(dev);
3216 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3217 	pci_set_drvdata(dev, ohci);
3218 
3219 	spin_lock_init(&ohci->lock);
3220 	mutex_init(&ohci->phy_reg_mutex);
3221 
3222 	tasklet_init(&ohci->bus_reset_tasklet,
3223 		     bus_reset_tasklet, (unsigned long)ohci);
3224 
3225 	err = pci_request_region(dev, 0, ohci_driver_name);
3226 	if (err) {
3227 		fw_error("MMIO resource unavailable\n");
3228 		goto fail_disable;
3229 	}
3230 
3231 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3232 	if (ohci->registers == NULL) {
3233 		fw_error("Failed to remap registers\n");
3234 		err = -ENXIO;
3235 		goto fail_iomem;
3236 	}
3237 
3238 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3239 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3240 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3241 		     ohci_quirks[i].device == dev->device) &&
3242 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3243 		     ohci_quirks[i].revision >= dev->revision)) {
3244 			ohci->quirks = ohci_quirks[i].flags;
3245 			break;
3246 		}
3247 	if (param_quirks)
3248 		ohci->quirks = param_quirks;
3249 
3250 	/*
3251 	 * Because dma_alloc_coherent() allocates at least one page,
3252 	 * we save space by using a common buffer for the AR request/
3253 	 * response descriptors and the self IDs buffer.
3254 	 */
3255 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3256 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3257 	ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3258 					       PAGE_SIZE,
3259 					       &ohci->misc_buffer_bus,
3260 					       GFP_KERNEL);
3261 	if (!ohci->misc_buffer) {
3262 		err = -ENOMEM;
3263 		goto fail_iounmap;
3264 	}
3265 
3266 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3267 			      OHCI1394_AsReqRcvContextControlSet);
3268 	if (err < 0)
3269 		goto fail_misc_buf;
3270 
3271 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3272 			      OHCI1394_AsRspRcvContextControlSet);
3273 	if (err < 0)
3274 		goto fail_arreq_ctx;
3275 
3276 	err = context_init(&ohci->at_request_ctx, ohci,
3277 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3278 	if (err < 0)
3279 		goto fail_arrsp_ctx;
3280 
3281 	err = context_init(&ohci->at_response_ctx, ohci,
3282 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3283 	if (err < 0)
3284 		goto fail_atreq_ctx;
3285 
3286 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3287 	ohci->ir_context_channels = ~0ULL;
3288 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3289 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3290 	ohci->ir_context_mask = ohci->ir_context_support;
3291 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3292 	size = sizeof(struct iso_context) * ohci->n_ir;
3293 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3294 
3295 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3296 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3297 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3298 	ohci->it_context_mask = ohci->it_context_support;
3299 	ohci->n_it = hweight32(ohci->it_context_mask);
3300 	size = sizeof(struct iso_context) * ohci->n_it;
3301 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3302 
3303 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3304 		err = -ENOMEM;
3305 		goto fail_contexts;
3306 	}
3307 
3308 	ohci->self_id_cpu = ohci->misc_buffer     + PAGE_SIZE/2;
3309 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3310 
3311 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3312 	max_receive = (bus_options >> 12) & 0xf;
3313 	link_speed = bus_options & 0x7;
3314 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3315 		reg_read(ohci, OHCI1394_GUIDLo);
3316 
3317 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3318 	if (err)
3319 		goto fail_contexts;
3320 
3321 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3322 	fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
3323 		  "%d IR + %d IT contexts, quirks 0x%x\n",
3324 		  dev_name(&dev->dev), version >> 16, version & 0xff,
3325 		  ohci->n_ir, ohci->n_it, ohci->quirks);
3326 
3327 	return 0;
3328 
3329  fail_contexts:
3330 	kfree(ohci->ir_context_list);
3331 	kfree(ohci->it_context_list);
3332 	context_release(&ohci->at_response_ctx);
3333  fail_atreq_ctx:
3334 	context_release(&ohci->at_request_ctx);
3335  fail_arrsp_ctx:
3336 	ar_context_release(&ohci->ar_response_ctx);
3337  fail_arreq_ctx:
3338 	ar_context_release(&ohci->ar_request_ctx);
3339  fail_misc_buf:
3340 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3341 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3342  fail_iounmap:
3343 	pci_iounmap(dev, ohci->registers);
3344  fail_iomem:
3345 	pci_release_region(dev, 0);
3346  fail_disable:
3347 	pci_disable_device(dev);
3348  fail_free:
3349 	kfree(ohci);
3350 	pmac_ohci_off(dev);
3351  fail:
3352 	if (err == -ENOMEM)
3353 		fw_error("Out of memory\n");
3354 
3355 	return err;
3356 }
3357 
3358 static void pci_remove(struct pci_dev *dev)
3359 {
3360 	struct fw_ohci *ohci;
3361 
3362 	ohci = pci_get_drvdata(dev);
3363 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3364 	flush_writes(ohci);
3365 	fw_core_remove_card(&ohci->card);
3366 
3367 	/*
3368 	 * FIXME: Fail all pending packets here, now that the upper
3369 	 * layers can't queue any more.
3370 	 */
3371 
3372 	software_reset(ohci);
3373 	free_irq(dev->irq, ohci);
3374 
3375 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3376 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3377 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3378 	if (ohci->config_rom)
3379 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3380 				  ohci->config_rom, ohci->config_rom_bus);
3381 	ar_context_release(&ohci->ar_request_ctx);
3382 	ar_context_release(&ohci->ar_response_ctx);
3383 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3384 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3385 	context_release(&ohci->at_request_ctx);
3386 	context_release(&ohci->at_response_ctx);
3387 	kfree(ohci->it_context_list);
3388 	kfree(ohci->ir_context_list);
3389 	pci_disable_msi(dev);
3390 	pci_iounmap(dev, ohci->registers);
3391 	pci_release_region(dev, 0);
3392 	pci_disable_device(dev);
3393 	kfree(ohci);
3394 	pmac_ohci_off(dev);
3395 
3396 	fw_notify("Removed fw-ohci device.\n");
3397 }
3398 
3399 #ifdef CONFIG_PM
3400 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3401 {
3402 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3403 	int err;
3404 
3405 	software_reset(ohci);
3406 	free_irq(dev->irq, ohci);
3407 	pci_disable_msi(dev);
3408 	err = pci_save_state(dev);
3409 	if (err) {
3410 		fw_error("pci_save_state failed\n");
3411 		return err;
3412 	}
3413 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3414 	if (err)
3415 		fw_error("pci_set_power_state failed with %d\n", err);
3416 	pmac_ohci_off(dev);
3417 
3418 	return 0;
3419 }
3420 
3421 static int pci_resume(struct pci_dev *dev)
3422 {
3423 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3424 	int err;
3425 
3426 	pmac_ohci_on(dev);
3427 	pci_set_power_state(dev, PCI_D0);
3428 	pci_restore_state(dev);
3429 	err = pci_enable_device(dev);
3430 	if (err) {
3431 		fw_error("pci_enable_device failed\n");
3432 		return err;
3433 	}
3434 
3435 	/* Some systems don't setup GUID register on resume from ram  */
3436 	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3437 					!reg_read(ohci, OHCI1394_GUIDHi)) {
3438 		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3439 		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3440 	}
3441 
3442 	err = ohci_enable(&ohci->card, NULL, 0);
3443 	if (err)
3444 		return err;
3445 
3446 	ohci_resume_iso_dma(ohci);
3447 
3448 	return 0;
3449 }
3450 #endif
3451 
3452 static const struct pci_device_id pci_table[] = {
3453 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3454 	{ }
3455 };
3456 
3457 MODULE_DEVICE_TABLE(pci, pci_table);
3458 
3459 static struct pci_driver fw_ohci_pci_driver = {
3460 	.name		= ohci_driver_name,
3461 	.id_table	= pci_table,
3462 	.probe		= pci_probe,
3463 	.remove		= pci_remove,
3464 #ifdef CONFIG_PM
3465 	.resume		= pci_resume,
3466 	.suspend	= pci_suspend,
3467 #endif
3468 };
3469 
3470 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3471 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3472 MODULE_LICENSE("GPL");
3473 
3474 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3475 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3476 MODULE_ALIAS("ohci1394");
3477 #endif
3478 
3479 static int __init fw_ohci_init(void)
3480 {
3481 	return pci_register_driver(&fw_ohci_pci_driver);
3482 }
3483 
3484 static void __exit fw_ohci_cleanup(void)
3485 {
3486 	pci_unregister_driver(&fw_ohci_pci_driver);
3487 }
3488 
3489 module_init(fw_ohci_init);
3490 module_exit(fw_ohci_cleanup);
3491