xref: /linux/drivers/firewire/ohci.c (revision a33f32244d8550da8b4a26e277ce07d5c6d158b5)
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/compiler.h>
22 #include <linux/delay.h>
23 #include <linux/device.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/firewire.h>
26 #include <linux/firewire-constants.h>
27 #include <linux/init.h>
28 #include <linux/interrupt.h>
29 #include <linux/io.h>
30 #include <linux/kernel.h>
31 #include <linux/list.h>
32 #include <linux/mm.h>
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/pci.h>
36 #include <linux/pci_ids.h>
37 #include <linux/slab.h>
38 #include <linux/spinlock.h>
39 #include <linux/string.h>
40 
41 #include <asm/byteorder.h>
42 #include <asm/page.h>
43 #include <asm/system.h>
44 
45 #ifdef CONFIG_PPC_PMAC
46 #include <asm/pmac_feature.h>
47 #endif
48 
49 #include "core.h"
50 #include "ohci.h"
51 
52 #define DESCRIPTOR_OUTPUT_MORE		0
53 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
54 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
55 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
56 #define DESCRIPTOR_STATUS		(1 << 11)
57 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
58 #define DESCRIPTOR_PING			(1 << 7)
59 #define DESCRIPTOR_YY			(1 << 6)
60 #define DESCRIPTOR_NO_IRQ		(0 << 4)
61 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
62 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
63 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
64 #define DESCRIPTOR_WAIT			(3 << 0)
65 
66 struct descriptor {
67 	__le16 req_count;
68 	__le16 control;
69 	__le32 data_address;
70 	__le32 branch_address;
71 	__le16 res_count;
72 	__le16 transfer_status;
73 } __attribute__((aligned(16)));
74 
75 #define CONTROL_SET(regs)	(regs)
76 #define CONTROL_CLEAR(regs)	((regs) + 4)
77 #define COMMAND_PTR(regs)	((regs) + 12)
78 #define CONTEXT_MATCH(regs)	((regs) + 16)
79 
80 struct ar_buffer {
81 	struct descriptor descriptor;
82 	struct ar_buffer *next;
83 	__le32 data[0];
84 };
85 
86 struct ar_context {
87 	struct fw_ohci *ohci;
88 	struct ar_buffer *current_buffer;
89 	struct ar_buffer *last_buffer;
90 	void *pointer;
91 	u32 regs;
92 	struct tasklet_struct tasklet;
93 };
94 
95 struct context;
96 
97 typedef int (*descriptor_callback_t)(struct context *ctx,
98 				     struct descriptor *d,
99 				     struct descriptor *last);
100 
101 /*
102  * A buffer that contains a block of DMA-able coherent memory used for
103  * storing a portion of a DMA descriptor program.
104  */
105 struct descriptor_buffer {
106 	struct list_head list;
107 	dma_addr_t buffer_bus;
108 	size_t buffer_size;
109 	size_t used;
110 	struct descriptor buffer[0];
111 };
112 
113 struct context {
114 	struct fw_ohci *ohci;
115 	u32 regs;
116 	int total_allocation;
117 
118 	/*
119 	 * List of page-sized buffers for storing DMA descriptors.
120 	 * Head of list contains buffers in use and tail of list contains
121 	 * free buffers.
122 	 */
123 	struct list_head buffer_list;
124 
125 	/*
126 	 * Pointer to a buffer inside buffer_list that contains the tail
127 	 * end of the current DMA program.
128 	 */
129 	struct descriptor_buffer *buffer_tail;
130 
131 	/*
132 	 * The descriptor containing the branch address of the first
133 	 * descriptor that has not yet been filled by the device.
134 	 */
135 	struct descriptor *last;
136 
137 	/*
138 	 * The last descriptor in the DMA program.  It contains the branch
139 	 * address that must be updated upon appending a new descriptor.
140 	 */
141 	struct descriptor *prev;
142 
143 	descriptor_callback_t callback;
144 
145 	struct tasklet_struct tasklet;
146 };
147 
148 #define IT_HEADER_SY(v)          ((v) <<  0)
149 #define IT_HEADER_TCODE(v)       ((v) <<  4)
150 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
151 #define IT_HEADER_TAG(v)         ((v) << 14)
152 #define IT_HEADER_SPEED(v)       ((v) << 16)
153 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
154 
155 struct iso_context {
156 	struct fw_iso_context base;
157 	struct context context;
158 	int excess_bytes;
159 	void *header;
160 	size_t header_length;
161 };
162 
163 #define CONFIG_ROM_SIZE 1024
164 
165 struct fw_ohci {
166 	struct fw_card card;
167 
168 	__iomem char *registers;
169 	int node_id;
170 	int generation;
171 	int request_generation;	/* for timestamping incoming requests */
172 	unsigned quirks;
173 
174 	/*
175 	 * Spinlock for accessing fw_ohci data.  Never call out of
176 	 * this driver with this lock held.
177 	 */
178 	spinlock_t lock;
179 
180 	struct ar_context ar_request_ctx;
181 	struct ar_context ar_response_ctx;
182 	struct context at_request_ctx;
183 	struct context at_response_ctx;
184 
185 	u32 it_context_mask;
186 	struct iso_context *it_context_list;
187 	u64 ir_context_channels;
188 	u32 ir_context_mask;
189 	struct iso_context *ir_context_list;
190 
191 	__be32    *config_rom;
192 	dma_addr_t config_rom_bus;
193 	__be32    *next_config_rom;
194 	dma_addr_t next_config_rom_bus;
195 	__be32     next_header;
196 
197 	__le32    *self_id_cpu;
198 	dma_addr_t self_id_bus;
199 	struct tasklet_struct bus_reset_tasklet;
200 
201 	u32 self_id_buffer[512];
202 };
203 
204 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
205 {
206 	return container_of(card, struct fw_ohci, card);
207 }
208 
209 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
210 #define IR_CONTEXT_BUFFER_FILL		0x80000000
211 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
212 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
213 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
214 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
215 
216 #define CONTEXT_RUN	0x8000
217 #define CONTEXT_WAKE	0x1000
218 #define CONTEXT_DEAD	0x0800
219 #define CONTEXT_ACTIVE	0x0400
220 
221 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
222 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
223 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
224 
225 #define OHCI1394_REGISTER_SIZE		0x800
226 #define OHCI_LOOP_COUNT			500
227 #define OHCI1394_PCI_HCI_Control	0x40
228 #define SELF_ID_BUF_SIZE		0x800
229 #define OHCI_TCODE_PHY_PACKET		0x0e
230 #define OHCI_VERSION_1_1		0x010010
231 
232 static char ohci_driver_name[] = KBUILD_MODNAME;
233 
234 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
235 
236 #define QUIRK_CYCLE_TIMER		1
237 #define QUIRK_RESET_PACKET		2
238 #define QUIRK_BE_HEADERS		4
239 
240 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
241 static const struct {
242 	unsigned short vendor, device, flags;
243 } ohci_quirks[] = {
244 	{PCI_VENDOR_ID_TI,	PCI_DEVICE_ID_TI_TSB12LV22, QUIRK_CYCLE_TIMER |
245 							    QUIRK_RESET_PACKET},
246 	{PCI_VENDOR_ID_TI,	PCI_ANY_ID,	QUIRK_RESET_PACKET},
247 	{PCI_VENDOR_ID_AL,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
248 	{PCI_VENDOR_ID_NEC,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
249 	{PCI_VENDOR_ID_VIA,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
250 	{PCI_VENDOR_ID_APPLE,	PCI_DEVICE_ID_APPLE_UNI_N_FW, QUIRK_BE_HEADERS},
251 };
252 
253 /* This overrides anything that was found in ohci_quirks[]. */
254 static int param_quirks;
255 module_param_named(quirks, param_quirks, int, 0644);
256 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
257 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
258 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
259 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
260 	")");
261 
262 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
263 
264 #define OHCI_PARAM_DEBUG_AT_AR		1
265 #define OHCI_PARAM_DEBUG_SELFIDS	2
266 #define OHCI_PARAM_DEBUG_IRQS		4
267 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
268 
269 static int param_debug;
270 module_param_named(debug, param_debug, int, 0644);
271 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
272 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
273 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
274 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
275 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
276 	", or a combination, or all = -1)");
277 
278 static void log_irqs(u32 evt)
279 {
280 	if (likely(!(param_debug &
281 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
282 		return;
283 
284 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
285 	    !(evt & OHCI1394_busReset))
286 		return;
287 
288 	fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
289 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
290 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
291 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
292 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
293 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
294 	    evt & OHCI1394_isochRx		? " IR"			: "",
295 	    evt & OHCI1394_isochTx		? " IT"			: "",
296 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
297 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
298 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
299 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
300 	    evt & OHCI1394_busReset		? " busReset"		: "",
301 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
302 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
303 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
304 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
305 		    OHCI1394_cycleTooLong | OHCI1394_cycleInconsistent |
306 		    OHCI1394_regAccessFail | OHCI1394_busReset)
307 						? " ?"			: "");
308 }
309 
310 static const char *speed[] = {
311 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
312 };
313 static const char *power[] = {
314 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
315 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
316 };
317 static const char port[] = { '.', '-', 'p', 'c', };
318 
319 static char _p(u32 *s, int shift)
320 {
321 	return port[*s >> shift & 3];
322 }
323 
324 static void log_selfids(int node_id, int generation, int self_id_count, u32 *s)
325 {
326 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
327 		return;
328 
329 	fw_notify("%d selfIDs, generation %d, local node ID %04x\n",
330 		  self_id_count, generation, node_id);
331 
332 	for (; self_id_count--; ++s)
333 		if ((*s & 1 << 23) == 0)
334 			fw_notify("selfID 0: %08x, phy %d [%c%c%c] "
335 			    "%s gc=%d %s %s%s%s\n",
336 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
337 			    speed[*s >> 14 & 3], *s >> 16 & 63,
338 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
339 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
340 		else
341 			fw_notify("selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
342 			    *s, *s >> 24 & 63,
343 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
344 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
345 }
346 
347 static const char *evts[] = {
348 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
349 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
350 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
351 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
352 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
353 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
354 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
355 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
356 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
357 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
358 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
359 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
360 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
361 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
362 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
363 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
364 	[0x20] = "pending/cancelled",
365 };
366 static const char *tcodes[] = {
367 	[0x0] = "QW req",		[0x1] = "BW req",
368 	[0x2] = "W resp",		[0x3] = "-reserved-",
369 	[0x4] = "QR req",		[0x5] = "BR req",
370 	[0x6] = "QR resp",		[0x7] = "BR resp",
371 	[0x8] = "cycle start",		[0x9] = "Lk req",
372 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
373 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
374 	[0xe] = "link internal",	[0xf] = "-reserved-",
375 };
376 static const char *phys[] = {
377 	[0x0] = "phy config packet",	[0x1] = "link-on packet",
378 	[0x2] = "self-id packet",	[0x3] = "-reserved-",
379 };
380 
381 static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
382 {
383 	int tcode = header[0] >> 4 & 0xf;
384 	char specific[12];
385 
386 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
387 		return;
388 
389 	if (unlikely(evt >= ARRAY_SIZE(evts)))
390 			evt = 0x1f;
391 
392 	if (evt == OHCI1394_evt_bus_reset) {
393 		fw_notify("A%c evt_bus_reset, generation %d\n",
394 		    dir, (header[2] >> 16) & 0xff);
395 		return;
396 	}
397 
398 	if (header[0] == ~header[1]) {
399 		fw_notify("A%c %s, %s, %08x\n",
400 		    dir, evts[evt], phys[header[0] >> 30 & 0x3], header[0]);
401 		return;
402 	}
403 
404 	switch (tcode) {
405 	case 0x0: case 0x6: case 0x8:
406 		snprintf(specific, sizeof(specific), " = %08x",
407 			 be32_to_cpu((__force __be32)header[3]));
408 		break;
409 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
410 		snprintf(specific, sizeof(specific), " %x,%x",
411 			 header[3] >> 16, header[3] & 0xffff);
412 		break;
413 	default:
414 		specific[0] = '\0';
415 	}
416 
417 	switch (tcode) {
418 	case 0xe: case 0xa:
419 		fw_notify("A%c %s, %s\n", dir, evts[evt], tcodes[tcode]);
420 		break;
421 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
422 		fw_notify("A%c spd %x tl %02x, "
423 		    "%04x -> %04x, %s, "
424 		    "%s, %04x%08x%s\n",
425 		    dir, speed, header[0] >> 10 & 0x3f,
426 		    header[1] >> 16, header[0] >> 16, evts[evt],
427 		    tcodes[tcode], header[1] & 0xffff, header[2], specific);
428 		break;
429 	default:
430 		fw_notify("A%c spd %x tl %02x, "
431 		    "%04x -> %04x, %s, "
432 		    "%s%s\n",
433 		    dir, speed, header[0] >> 10 & 0x3f,
434 		    header[1] >> 16, header[0] >> 16, evts[evt],
435 		    tcodes[tcode], specific);
436 	}
437 }
438 
439 #else
440 
441 #define log_irqs(evt)
442 #define log_selfids(node_id, generation, self_id_count, sid)
443 #define log_ar_at_event(dir, speed, header, evt)
444 
445 #endif /* CONFIG_FIREWIRE_OHCI_DEBUG */
446 
447 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
448 {
449 	writel(data, ohci->registers + offset);
450 }
451 
452 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
453 {
454 	return readl(ohci->registers + offset);
455 }
456 
457 static inline void flush_writes(const struct fw_ohci *ohci)
458 {
459 	/* Do a dummy read to flush writes. */
460 	reg_read(ohci, OHCI1394_Version);
461 }
462 
463 static int ohci_update_phy_reg(struct fw_card *card, int addr,
464 			       int clear_bits, int set_bits)
465 {
466 	struct fw_ohci *ohci = fw_ohci(card);
467 	u32 val, old;
468 
469 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
470 	flush_writes(ohci);
471 	msleep(2);
472 	val = reg_read(ohci, OHCI1394_PhyControl);
473 	if ((val & OHCI1394_PhyControl_ReadDone) == 0) {
474 		fw_error("failed to set phy reg bits.\n");
475 		return -EBUSY;
476 	}
477 
478 	old = OHCI1394_PhyControl_ReadData(val);
479 	old = (old & ~clear_bits) | set_bits;
480 	reg_write(ohci, OHCI1394_PhyControl,
481 		  OHCI1394_PhyControl_Write(addr, old));
482 
483 	return 0;
484 }
485 
486 static int ar_context_add_page(struct ar_context *ctx)
487 {
488 	struct device *dev = ctx->ohci->card.device;
489 	struct ar_buffer *ab;
490 	dma_addr_t uninitialized_var(ab_bus);
491 	size_t offset;
492 
493 	ab = dma_alloc_coherent(dev, PAGE_SIZE, &ab_bus, GFP_ATOMIC);
494 	if (ab == NULL)
495 		return -ENOMEM;
496 
497 	ab->next = NULL;
498 	memset(&ab->descriptor, 0, sizeof(ab->descriptor));
499 	ab->descriptor.control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
500 						    DESCRIPTOR_STATUS |
501 						    DESCRIPTOR_BRANCH_ALWAYS);
502 	offset = offsetof(struct ar_buffer, data);
503 	ab->descriptor.req_count      = cpu_to_le16(PAGE_SIZE - offset);
504 	ab->descriptor.data_address   = cpu_to_le32(ab_bus + offset);
505 	ab->descriptor.res_count      = cpu_to_le16(PAGE_SIZE - offset);
506 	ab->descriptor.branch_address = 0;
507 
508 	ctx->last_buffer->descriptor.branch_address = cpu_to_le32(ab_bus | 1);
509 	ctx->last_buffer->next = ab;
510 	ctx->last_buffer = ab;
511 
512 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
513 	flush_writes(ctx->ohci);
514 
515 	return 0;
516 }
517 
518 static void ar_context_release(struct ar_context *ctx)
519 {
520 	struct ar_buffer *ab, *ab_next;
521 	size_t offset;
522 	dma_addr_t ab_bus;
523 
524 	for (ab = ctx->current_buffer; ab; ab = ab_next) {
525 		ab_next = ab->next;
526 		offset = offsetof(struct ar_buffer, data);
527 		ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
528 		dma_free_coherent(ctx->ohci->card.device, PAGE_SIZE,
529 				  ab, ab_bus);
530 	}
531 }
532 
533 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
534 #define cond_le32_to_cpu(v) \
535 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
536 #else
537 #define cond_le32_to_cpu(v) le32_to_cpu(v)
538 #endif
539 
540 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
541 {
542 	struct fw_ohci *ohci = ctx->ohci;
543 	struct fw_packet p;
544 	u32 status, length, tcode;
545 	int evt;
546 
547 	p.header[0] = cond_le32_to_cpu(buffer[0]);
548 	p.header[1] = cond_le32_to_cpu(buffer[1]);
549 	p.header[2] = cond_le32_to_cpu(buffer[2]);
550 
551 	tcode = (p.header[0] >> 4) & 0x0f;
552 	switch (tcode) {
553 	case TCODE_WRITE_QUADLET_REQUEST:
554 	case TCODE_READ_QUADLET_RESPONSE:
555 		p.header[3] = (__force __u32) buffer[3];
556 		p.header_length = 16;
557 		p.payload_length = 0;
558 		break;
559 
560 	case TCODE_READ_BLOCK_REQUEST :
561 		p.header[3] = cond_le32_to_cpu(buffer[3]);
562 		p.header_length = 16;
563 		p.payload_length = 0;
564 		break;
565 
566 	case TCODE_WRITE_BLOCK_REQUEST:
567 	case TCODE_READ_BLOCK_RESPONSE:
568 	case TCODE_LOCK_REQUEST:
569 	case TCODE_LOCK_RESPONSE:
570 		p.header[3] = cond_le32_to_cpu(buffer[3]);
571 		p.header_length = 16;
572 		p.payload_length = p.header[3] >> 16;
573 		break;
574 
575 	case TCODE_WRITE_RESPONSE:
576 	case TCODE_READ_QUADLET_REQUEST:
577 	case OHCI_TCODE_PHY_PACKET:
578 		p.header_length = 12;
579 		p.payload_length = 0;
580 		break;
581 
582 	default:
583 		/* FIXME: Stop context, discard everything, and restart? */
584 		p.header_length = 0;
585 		p.payload_length = 0;
586 	}
587 
588 	p.payload = (void *) buffer + p.header_length;
589 
590 	/* FIXME: What to do about evt_* errors? */
591 	length = (p.header_length + p.payload_length + 3) / 4;
592 	status = cond_le32_to_cpu(buffer[length]);
593 	evt    = (status >> 16) & 0x1f;
594 
595 	p.ack        = evt - 16;
596 	p.speed      = (status >> 21) & 0x7;
597 	p.timestamp  = status & 0xffff;
598 	p.generation = ohci->request_generation;
599 
600 	log_ar_at_event('R', p.speed, p.header, evt);
601 
602 	/*
603 	 * The OHCI bus reset handler synthesizes a phy packet with
604 	 * the new generation number when a bus reset happens (see
605 	 * section 8.4.2.3).  This helps us determine when a request
606 	 * was received and make sure we send the response in the same
607 	 * generation.  We only need this for requests; for responses
608 	 * we use the unique tlabel for finding the matching
609 	 * request.
610 	 *
611 	 * Alas some chips sometimes emit bus reset packets with a
612 	 * wrong generation.  We set the correct generation for these
613 	 * at a slightly incorrect time (in bus_reset_tasklet).
614 	 */
615 	if (evt == OHCI1394_evt_bus_reset) {
616 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
617 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
618 	} else if (ctx == &ohci->ar_request_ctx) {
619 		fw_core_handle_request(&ohci->card, &p);
620 	} else {
621 		fw_core_handle_response(&ohci->card, &p);
622 	}
623 
624 	return buffer + length + 1;
625 }
626 
627 static void ar_context_tasklet(unsigned long data)
628 {
629 	struct ar_context *ctx = (struct ar_context *)data;
630 	struct fw_ohci *ohci = ctx->ohci;
631 	struct ar_buffer *ab;
632 	struct descriptor *d;
633 	void *buffer, *end;
634 
635 	ab = ctx->current_buffer;
636 	d = &ab->descriptor;
637 
638 	if (d->res_count == 0) {
639 		size_t size, rest, offset;
640 		dma_addr_t start_bus;
641 		void *start;
642 
643 		/*
644 		 * This descriptor is finished and we may have a
645 		 * packet split across this and the next buffer. We
646 		 * reuse the page for reassembling the split packet.
647 		 */
648 
649 		offset = offsetof(struct ar_buffer, data);
650 		start = buffer = ab;
651 		start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
652 
653 		ab = ab->next;
654 		d = &ab->descriptor;
655 		size = buffer + PAGE_SIZE - ctx->pointer;
656 		rest = le16_to_cpu(d->req_count) - le16_to_cpu(d->res_count);
657 		memmove(buffer, ctx->pointer, size);
658 		memcpy(buffer + size, ab->data, rest);
659 		ctx->current_buffer = ab;
660 		ctx->pointer = (void *) ab->data + rest;
661 		end = buffer + size + rest;
662 
663 		while (buffer < end)
664 			buffer = handle_ar_packet(ctx, buffer);
665 
666 		dma_free_coherent(ohci->card.device, PAGE_SIZE,
667 				  start, start_bus);
668 		ar_context_add_page(ctx);
669 	} else {
670 		buffer = ctx->pointer;
671 		ctx->pointer = end =
672 			(void *) ab + PAGE_SIZE - le16_to_cpu(d->res_count);
673 
674 		while (buffer < end)
675 			buffer = handle_ar_packet(ctx, buffer);
676 	}
677 }
678 
679 static int ar_context_init(struct ar_context *ctx,
680 			   struct fw_ohci *ohci, u32 regs)
681 {
682 	struct ar_buffer ab;
683 
684 	ctx->regs        = regs;
685 	ctx->ohci        = ohci;
686 	ctx->last_buffer = &ab;
687 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
688 
689 	ar_context_add_page(ctx);
690 	ar_context_add_page(ctx);
691 	ctx->current_buffer = ab.next;
692 	ctx->pointer = ctx->current_buffer->data;
693 
694 	return 0;
695 }
696 
697 static void ar_context_run(struct ar_context *ctx)
698 {
699 	struct ar_buffer *ab = ctx->current_buffer;
700 	dma_addr_t ab_bus;
701 	size_t offset;
702 
703 	offset = offsetof(struct ar_buffer, data);
704 	ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
705 
706 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ab_bus | 1);
707 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
708 	flush_writes(ctx->ohci);
709 }
710 
711 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
712 {
713 	int b, key;
714 
715 	b   = (le16_to_cpu(d->control) & DESCRIPTOR_BRANCH_ALWAYS) >> 2;
716 	key = (le16_to_cpu(d->control) & DESCRIPTOR_KEY_IMMEDIATE) >> 8;
717 
718 	/* figure out which descriptor the branch address goes in */
719 	if (z == 2 && (b == 3 || key == 2))
720 		return d;
721 	else
722 		return d + z - 1;
723 }
724 
725 static void context_tasklet(unsigned long data)
726 {
727 	struct context *ctx = (struct context *) data;
728 	struct descriptor *d, *last;
729 	u32 address;
730 	int z;
731 	struct descriptor_buffer *desc;
732 
733 	desc = list_entry(ctx->buffer_list.next,
734 			struct descriptor_buffer, list);
735 	last = ctx->last;
736 	while (last->branch_address != 0) {
737 		struct descriptor_buffer *old_desc = desc;
738 		address = le32_to_cpu(last->branch_address);
739 		z = address & 0xf;
740 		address &= ~0xf;
741 
742 		/* If the branch address points to a buffer outside of the
743 		 * current buffer, advance to the next buffer. */
744 		if (address < desc->buffer_bus ||
745 				address >= desc->buffer_bus + desc->used)
746 			desc = list_entry(desc->list.next,
747 					struct descriptor_buffer, list);
748 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
749 		last = find_branch_descriptor(d, z);
750 
751 		if (!ctx->callback(ctx, d, last))
752 			break;
753 
754 		if (old_desc != desc) {
755 			/* If we've advanced to the next buffer, move the
756 			 * previous buffer to the free list. */
757 			unsigned long flags;
758 			old_desc->used = 0;
759 			spin_lock_irqsave(&ctx->ohci->lock, flags);
760 			list_move_tail(&old_desc->list, &ctx->buffer_list);
761 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
762 		}
763 		ctx->last = last;
764 	}
765 }
766 
767 /*
768  * Allocate a new buffer and add it to the list of free buffers for this
769  * context.  Must be called with ohci->lock held.
770  */
771 static int context_add_buffer(struct context *ctx)
772 {
773 	struct descriptor_buffer *desc;
774 	dma_addr_t uninitialized_var(bus_addr);
775 	int offset;
776 
777 	/*
778 	 * 16MB of descriptors should be far more than enough for any DMA
779 	 * program.  This will catch run-away userspace or DoS attacks.
780 	 */
781 	if (ctx->total_allocation >= 16*1024*1024)
782 		return -ENOMEM;
783 
784 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
785 			&bus_addr, GFP_ATOMIC);
786 	if (!desc)
787 		return -ENOMEM;
788 
789 	offset = (void *)&desc->buffer - (void *)desc;
790 	desc->buffer_size = PAGE_SIZE - offset;
791 	desc->buffer_bus = bus_addr + offset;
792 	desc->used = 0;
793 
794 	list_add_tail(&desc->list, &ctx->buffer_list);
795 	ctx->total_allocation += PAGE_SIZE;
796 
797 	return 0;
798 }
799 
800 static int context_init(struct context *ctx, struct fw_ohci *ohci,
801 			u32 regs, descriptor_callback_t callback)
802 {
803 	ctx->ohci = ohci;
804 	ctx->regs = regs;
805 	ctx->total_allocation = 0;
806 
807 	INIT_LIST_HEAD(&ctx->buffer_list);
808 	if (context_add_buffer(ctx) < 0)
809 		return -ENOMEM;
810 
811 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
812 			struct descriptor_buffer, list);
813 
814 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
815 	ctx->callback = callback;
816 
817 	/*
818 	 * We put a dummy descriptor in the buffer that has a NULL
819 	 * branch address and looks like it's been sent.  That way we
820 	 * have a descriptor to append DMA programs to.
821 	 */
822 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
823 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
824 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
825 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
826 	ctx->last = ctx->buffer_tail->buffer;
827 	ctx->prev = ctx->buffer_tail->buffer;
828 
829 	return 0;
830 }
831 
832 static void context_release(struct context *ctx)
833 {
834 	struct fw_card *card = &ctx->ohci->card;
835 	struct descriptor_buffer *desc, *tmp;
836 
837 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
838 		dma_free_coherent(card->device, PAGE_SIZE, desc,
839 			desc->buffer_bus -
840 			((void *)&desc->buffer - (void *)desc));
841 }
842 
843 /* Must be called with ohci->lock held */
844 static struct descriptor *context_get_descriptors(struct context *ctx,
845 						  int z, dma_addr_t *d_bus)
846 {
847 	struct descriptor *d = NULL;
848 	struct descriptor_buffer *desc = ctx->buffer_tail;
849 
850 	if (z * sizeof(*d) > desc->buffer_size)
851 		return NULL;
852 
853 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
854 		/* No room for the descriptor in this buffer, so advance to the
855 		 * next one. */
856 
857 		if (desc->list.next == &ctx->buffer_list) {
858 			/* If there is no free buffer next in the list,
859 			 * allocate one. */
860 			if (context_add_buffer(ctx) < 0)
861 				return NULL;
862 		}
863 		desc = list_entry(desc->list.next,
864 				struct descriptor_buffer, list);
865 		ctx->buffer_tail = desc;
866 	}
867 
868 	d = desc->buffer + desc->used / sizeof(*d);
869 	memset(d, 0, z * sizeof(*d));
870 	*d_bus = desc->buffer_bus + desc->used;
871 
872 	return d;
873 }
874 
875 static void context_run(struct context *ctx, u32 extra)
876 {
877 	struct fw_ohci *ohci = ctx->ohci;
878 
879 	reg_write(ohci, COMMAND_PTR(ctx->regs),
880 		  le32_to_cpu(ctx->last->branch_address));
881 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
882 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
883 	flush_writes(ohci);
884 }
885 
886 static void context_append(struct context *ctx,
887 			   struct descriptor *d, int z, int extra)
888 {
889 	dma_addr_t d_bus;
890 	struct descriptor_buffer *desc = ctx->buffer_tail;
891 
892 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
893 
894 	desc->used += (z + extra) * sizeof(*d);
895 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
896 	ctx->prev = find_branch_descriptor(d, z);
897 
898 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
899 	flush_writes(ctx->ohci);
900 }
901 
902 static void context_stop(struct context *ctx)
903 {
904 	u32 reg;
905 	int i;
906 
907 	reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
908 	flush_writes(ctx->ohci);
909 
910 	for (i = 0; i < 10; i++) {
911 		reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
912 		if ((reg & CONTEXT_ACTIVE) == 0)
913 			return;
914 
915 		mdelay(1);
916 	}
917 	fw_error("Error: DMA context still active (0x%08x)\n", reg);
918 }
919 
920 struct driver_data {
921 	struct fw_packet *packet;
922 };
923 
924 /*
925  * This function apppends a packet to the DMA queue for transmission.
926  * Must always be called with the ochi->lock held to ensure proper
927  * generation handling and locking around packet queue manipulation.
928  */
929 static int at_context_queue_packet(struct context *ctx,
930 				   struct fw_packet *packet)
931 {
932 	struct fw_ohci *ohci = ctx->ohci;
933 	dma_addr_t d_bus, uninitialized_var(payload_bus);
934 	struct driver_data *driver_data;
935 	struct descriptor *d, *last;
936 	__le32 *header;
937 	int z, tcode;
938 	u32 reg;
939 
940 	d = context_get_descriptors(ctx, 4, &d_bus);
941 	if (d == NULL) {
942 		packet->ack = RCODE_SEND_ERROR;
943 		return -1;
944 	}
945 
946 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
947 	d[0].res_count = cpu_to_le16(packet->timestamp);
948 
949 	/*
950 	 * The DMA format for asyncronous link packets is different
951 	 * from the IEEE1394 layout, so shift the fields around
952 	 * accordingly.  If header_length is 8, it's a PHY packet, to
953 	 * which we need to prepend an extra quadlet.
954 	 */
955 
956 	header = (__le32 *) &d[1];
957 	switch (packet->header_length) {
958 	case 16:
959 	case 12:
960 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
961 					(packet->speed << 16));
962 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
963 					(packet->header[0] & 0xffff0000));
964 		header[2] = cpu_to_le32(packet->header[2]);
965 
966 		tcode = (packet->header[0] >> 4) & 0x0f;
967 		if (TCODE_IS_BLOCK_PACKET(tcode))
968 			header[3] = cpu_to_le32(packet->header[3]);
969 		else
970 			header[3] = (__force __le32) packet->header[3];
971 
972 		d[0].req_count = cpu_to_le16(packet->header_length);
973 		break;
974 
975 	case 8:
976 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
977 					(packet->speed << 16));
978 		header[1] = cpu_to_le32(packet->header[0]);
979 		header[2] = cpu_to_le32(packet->header[1]);
980 		d[0].req_count = cpu_to_le16(12);
981 		break;
982 
983 	case 4:
984 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
985 					(packet->speed << 16));
986 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
987 		d[0].req_count = cpu_to_le16(8);
988 		break;
989 
990 	default:
991 		/* BUG(); */
992 		packet->ack = RCODE_SEND_ERROR;
993 		return -1;
994 	}
995 
996 	driver_data = (struct driver_data *) &d[3];
997 	driver_data->packet = packet;
998 	packet->driver_data = driver_data;
999 
1000 	if (packet->payload_length > 0) {
1001 		payload_bus =
1002 			dma_map_single(ohci->card.device, packet->payload,
1003 				       packet->payload_length, DMA_TO_DEVICE);
1004 		if (dma_mapping_error(ohci->card.device, payload_bus)) {
1005 			packet->ack = RCODE_SEND_ERROR;
1006 			return -1;
1007 		}
1008 		packet->payload_bus	= payload_bus;
1009 		packet->payload_mapped	= true;
1010 
1011 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1012 		d[2].data_address = cpu_to_le32(payload_bus);
1013 		last = &d[2];
1014 		z = 3;
1015 	} else {
1016 		last = &d[0];
1017 		z = 2;
1018 	}
1019 
1020 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1021 				     DESCRIPTOR_IRQ_ALWAYS |
1022 				     DESCRIPTOR_BRANCH_ALWAYS);
1023 
1024 	/*
1025 	 * If the controller and packet generations don't match, we need to
1026 	 * bail out and try again.  If IntEvent.busReset is set, the AT context
1027 	 * is halted, so appending to the context and trying to run it is
1028 	 * futile.  Most controllers do the right thing and just flush the AT
1029 	 * queue (per section 7.2.3.2 of the OHCI 1.1 specification), but
1030 	 * some controllers (like a JMicron JMB381 PCI-e) misbehave and wind
1031 	 * up stalling out.  So we just bail out in software and try again
1032 	 * later, and everyone is happy.
1033 	 * FIXME: Document how the locking works.
1034 	 */
1035 	if (ohci->generation != packet->generation ||
1036 	    reg_read(ohci, OHCI1394_IntEventSet) & OHCI1394_busReset) {
1037 		if (packet->payload_mapped)
1038 			dma_unmap_single(ohci->card.device, payload_bus,
1039 					 packet->payload_length, DMA_TO_DEVICE);
1040 		packet->ack = RCODE_GENERATION;
1041 		return -1;
1042 	}
1043 
1044 	context_append(ctx, d, z, 4 - z);
1045 
1046 	/* If the context isn't already running, start it up. */
1047 	reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1048 	if ((reg & CONTEXT_RUN) == 0)
1049 		context_run(ctx, 0);
1050 
1051 	return 0;
1052 }
1053 
1054 static int handle_at_packet(struct context *context,
1055 			    struct descriptor *d,
1056 			    struct descriptor *last)
1057 {
1058 	struct driver_data *driver_data;
1059 	struct fw_packet *packet;
1060 	struct fw_ohci *ohci = context->ohci;
1061 	int evt;
1062 
1063 	if (last->transfer_status == 0)
1064 		/* This descriptor isn't done yet, stop iteration. */
1065 		return 0;
1066 
1067 	driver_data = (struct driver_data *) &d[3];
1068 	packet = driver_data->packet;
1069 	if (packet == NULL)
1070 		/* This packet was cancelled, just continue. */
1071 		return 1;
1072 
1073 	if (packet->payload_mapped)
1074 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1075 				 packet->payload_length, DMA_TO_DEVICE);
1076 
1077 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1078 	packet->timestamp = le16_to_cpu(last->res_count);
1079 
1080 	log_ar_at_event('T', packet->speed, packet->header, evt);
1081 
1082 	switch (evt) {
1083 	case OHCI1394_evt_timeout:
1084 		/* Async response transmit timed out. */
1085 		packet->ack = RCODE_CANCELLED;
1086 		break;
1087 
1088 	case OHCI1394_evt_flushed:
1089 		/*
1090 		 * The packet was flushed should give same error as
1091 		 * when we try to use a stale generation count.
1092 		 */
1093 		packet->ack = RCODE_GENERATION;
1094 		break;
1095 
1096 	case OHCI1394_evt_missing_ack:
1097 		/*
1098 		 * Using a valid (current) generation count, but the
1099 		 * node is not on the bus or not sending acks.
1100 		 */
1101 		packet->ack = RCODE_NO_ACK;
1102 		break;
1103 
1104 	case ACK_COMPLETE + 0x10:
1105 	case ACK_PENDING + 0x10:
1106 	case ACK_BUSY_X + 0x10:
1107 	case ACK_BUSY_A + 0x10:
1108 	case ACK_BUSY_B + 0x10:
1109 	case ACK_DATA_ERROR + 0x10:
1110 	case ACK_TYPE_ERROR + 0x10:
1111 		packet->ack = evt - 0x10;
1112 		break;
1113 
1114 	default:
1115 		packet->ack = RCODE_SEND_ERROR;
1116 		break;
1117 	}
1118 
1119 	packet->callback(packet, &ohci->card, packet->ack);
1120 
1121 	return 1;
1122 }
1123 
1124 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1125 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1126 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1127 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1128 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1129 
1130 static void handle_local_rom(struct fw_ohci *ohci,
1131 			     struct fw_packet *packet, u32 csr)
1132 {
1133 	struct fw_packet response;
1134 	int tcode, length, i;
1135 
1136 	tcode = HEADER_GET_TCODE(packet->header[0]);
1137 	if (TCODE_IS_BLOCK_PACKET(tcode))
1138 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1139 	else
1140 		length = 4;
1141 
1142 	i = csr - CSR_CONFIG_ROM;
1143 	if (i + length > CONFIG_ROM_SIZE) {
1144 		fw_fill_response(&response, packet->header,
1145 				 RCODE_ADDRESS_ERROR, NULL, 0);
1146 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1147 		fw_fill_response(&response, packet->header,
1148 				 RCODE_TYPE_ERROR, NULL, 0);
1149 	} else {
1150 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1151 				 (void *) ohci->config_rom + i, length);
1152 	}
1153 
1154 	fw_core_handle_response(&ohci->card, &response);
1155 }
1156 
1157 static void handle_local_lock(struct fw_ohci *ohci,
1158 			      struct fw_packet *packet, u32 csr)
1159 {
1160 	struct fw_packet response;
1161 	int tcode, length, ext_tcode, sel;
1162 	__be32 *payload, lock_old;
1163 	u32 lock_arg, lock_data;
1164 
1165 	tcode = HEADER_GET_TCODE(packet->header[0]);
1166 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1167 	payload = packet->payload;
1168 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1169 
1170 	if (tcode == TCODE_LOCK_REQUEST &&
1171 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1172 		lock_arg = be32_to_cpu(payload[0]);
1173 		lock_data = be32_to_cpu(payload[1]);
1174 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1175 		lock_arg = 0;
1176 		lock_data = 0;
1177 	} else {
1178 		fw_fill_response(&response, packet->header,
1179 				 RCODE_TYPE_ERROR, NULL, 0);
1180 		goto out;
1181 	}
1182 
1183 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1184 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1185 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1186 	reg_write(ohci, OHCI1394_CSRControl, sel);
1187 
1188 	if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000)
1189 		lock_old = cpu_to_be32(reg_read(ohci, OHCI1394_CSRData));
1190 	else
1191 		fw_notify("swap not done yet\n");
1192 
1193 	fw_fill_response(&response, packet->header,
1194 			 RCODE_COMPLETE, &lock_old, sizeof(lock_old));
1195  out:
1196 	fw_core_handle_response(&ohci->card, &response);
1197 }
1198 
1199 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1200 {
1201 	u64 offset;
1202 	u32 csr;
1203 
1204 	if (ctx == &ctx->ohci->at_request_ctx) {
1205 		packet->ack = ACK_PENDING;
1206 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1207 	}
1208 
1209 	offset =
1210 		((unsigned long long)
1211 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1212 		packet->header[2];
1213 	csr = offset - CSR_REGISTER_BASE;
1214 
1215 	/* Handle config rom reads. */
1216 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1217 		handle_local_rom(ctx->ohci, packet, csr);
1218 	else switch (csr) {
1219 	case CSR_BUS_MANAGER_ID:
1220 	case CSR_BANDWIDTH_AVAILABLE:
1221 	case CSR_CHANNELS_AVAILABLE_HI:
1222 	case CSR_CHANNELS_AVAILABLE_LO:
1223 		handle_local_lock(ctx->ohci, packet, csr);
1224 		break;
1225 	default:
1226 		if (ctx == &ctx->ohci->at_request_ctx)
1227 			fw_core_handle_request(&ctx->ohci->card, packet);
1228 		else
1229 			fw_core_handle_response(&ctx->ohci->card, packet);
1230 		break;
1231 	}
1232 
1233 	if (ctx == &ctx->ohci->at_response_ctx) {
1234 		packet->ack = ACK_COMPLETE;
1235 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1236 	}
1237 }
1238 
1239 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1240 {
1241 	unsigned long flags;
1242 	int ret;
1243 
1244 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1245 
1246 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1247 	    ctx->ohci->generation == packet->generation) {
1248 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1249 		handle_local_request(ctx, packet);
1250 		return;
1251 	}
1252 
1253 	ret = at_context_queue_packet(ctx, packet);
1254 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1255 
1256 	if (ret < 0)
1257 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1258 
1259 }
1260 
1261 static void bus_reset_tasklet(unsigned long data)
1262 {
1263 	struct fw_ohci *ohci = (struct fw_ohci *)data;
1264 	int self_id_count, i, j, reg;
1265 	int generation, new_generation;
1266 	unsigned long flags;
1267 	void *free_rom = NULL;
1268 	dma_addr_t free_rom_bus = 0;
1269 
1270 	reg = reg_read(ohci, OHCI1394_NodeID);
1271 	if (!(reg & OHCI1394_NodeID_idValid)) {
1272 		fw_notify("node ID not valid, new bus reset in progress\n");
1273 		return;
1274 	}
1275 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1276 		fw_notify("malconfigured bus\n");
1277 		return;
1278 	}
1279 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1280 			       OHCI1394_NodeID_nodeNumber);
1281 
1282 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1283 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1284 		fw_notify("inconsistent self IDs\n");
1285 		return;
1286 	}
1287 	/*
1288 	 * The count in the SelfIDCount register is the number of
1289 	 * bytes in the self ID receive buffer.  Since we also receive
1290 	 * the inverted quadlets and a header quadlet, we shift one
1291 	 * bit extra to get the actual number of self IDs.
1292 	 */
1293 	self_id_count = (reg >> 3) & 0xff;
1294 	if (self_id_count == 0 || self_id_count > 252) {
1295 		fw_notify("inconsistent self IDs\n");
1296 		return;
1297 	}
1298 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1299 	rmb();
1300 
1301 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1302 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1303 			fw_notify("inconsistent self IDs\n");
1304 			return;
1305 		}
1306 		ohci->self_id_buffer[j] =
1307 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1308 	}
1309 	rmb();
1310 
1311 	/*
1312 	 * Check the consistency of the self IDs we just read.  The
1313 	 * problem we face is that a new bus reset can start while we
1314 	 * read out the self IDs from the DMA buffer. If this happens,
1315 	 * the DMA buffer will be overwritten with new self IDs and we
1316 	 * will read out inconsistent data.  The OHCI specification
1317 	 * (section 11.2) recommends a technique similar to
1318 	 * linux/seqlock.h, where we remember the generation of the
1319 	 * self IDs in the buffer before reading them out and compare
1320 	 * it to the current generation after reading them out.  If
1321 	 * the two generations match we know we have a consistent set
1322 	 * of self IDs.
1323 	 */
1324 
1325 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1326 	if (new_generation != generation) {
1327 		fw_notify("recursive bus reset detected, "
1328 			  "discarding self ids\n");
1329 		return;
1330 	}
1331 
1332 	/* FIXME: Document how the locking works. */
1333 	spin_lock_irqsave(&ohci->lock, flags);
1334 
1335 	ohci->generation = generation;
1336 	context_stop(&ohci->at_request_ctx);
1337 	context_stop(&ohci->at_response_ctx);
1338 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1339 
1340 	if (ohci->quirks & QUIRK_RESET_PACKET)
1341 		ohci->request_generation = generation;
1342 
1343 	/*
1344 	 * This next bit is unrelated to the AT context stuff but we
1345 	 * have to do it under the spinlock also.  If a new config rom
1346 	 * was set up before this reset, the old one is now no longer
1347 	 * in use and we can free it. Update the config rom pointers
1348 	 * to point to the current config rom and clear the
1349 	 * next_config_rom pointer so a new update can take place.
1350 	 */
1351 
1352 	if (ohci->next_config_rom != NULL) {
1353 		if (ohci->next_config_rom != ohci->config_rom) {
1354 			free_rom      = ohci->config_rom;
1355 			free_rom_bus  = ohci->config_rom_bus;
1356 		}
1357 		ohci->config_rom      = ohci->next_config_rom;
1358 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1359 		ohci->next_config_rom = NULL;
1360 
1361 		/*
1362 		 * Restore config_rom image and manually update
1363 		 * config_rom registers.  Writing the header quadlet
1364 		 * will indicate that the config rom is ready, so we
1365 		 * do that last.
1366 		 */
1367 		reg_write(ohci, OHCI1394_BusOptions,
1368 			  be32_to_cpu(ohci->config_rom[2]));
1369 		ohci->config_rom[0] = ohci->next_header;
1370 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1371 			  be32_to_cpu(ohci->next_header));
1372 	}
1373 
1374 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1375 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1376 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1377 #endif
1378 
1379 	spin_unlock_irqrestore(&ohci->lock, flags);
1380 
1381 	if (free_rom)
1382 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1383 				  free_rom, free_rom_bus);
1384 
1385 	log_selfids(ohci->node_id, generation,
1386 		    self_id_count, ohci->self_id_buffer);
1387 
1388 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1389 				 self_id_count, ohci->self_id_buffer);
1390 }
1391 
1392 static irqreturn_t irq_handler(int irq, void *data)
1393 {
1394 	struct fw_ohci *ohci = data;
1395 	u32 event, iso_event;
1396 	int i;
1397 
1398 	event = reg_read(ohci, OHCI1394_IntEventClear);
1399 
1400 	if (!event || !~event)
1401 		return IRQ_NONE;
1402 
1403 	/* busReset must not be cleared yet, see OHCI 1.1 clause 7.2.3.2 */
1404 	reg_write(ohci, OHCI1394_IntEventClear, event & ~OHCI1394_busReset);
1405 	log_irqs(event);
1406 
1407 	if (event & OHCI1394_selfIDComplete)
1408 		tasklet_schedule(&ohci->bus_reset_tasklet);
1409 
1410 	if (event & OHCI1394_RQPkt)
1411 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1412 
1413 	if (event & OHCI1394_RSPkt)
1414 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1415 
1416 	if (event & OHCI1394_reqTxComplete)
1417 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
1418 
1419 	if (event & OHCI1394_respTxComplete)
1420 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
1421 
1422 	iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1423 	reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1424 
1425 	while (iso_event) {
1426 		i = ffs(iso_event) - 1;
1427 		tasklet_schedule(&ohci->ir_context_list[i].context.tasklet);
1428 		iso_event &= ~(1 << i);
1429 	}
1430 
1431 	iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1432 	reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1433 
1434 	while (iso_event) {
1435 		i = ffs(iso_event) - 1;
1436 		tasklet_schedule(&ohci->it_context_list[i].context.tasklet);
1437 		iso_event &= ~(1 << i);
1438 	}
1439 
1440 	if (unlikely(event & OHCI1394_regAccessFail))
1441 		fw_error("Register access failure - "
1442 			 "please notify linux1394-devel@lists.sf.net\n");
1443 
1444 	if (unlikely(event & OHCI1394_postedWriteErr))
1445 		fw_error("PCI posted write error\n");
1446 
1447 	if (unlikely(event & OHCI1394_cycleTooLong)) {
1448 		if (printk_ratelimit())
1449 			fw_notify("isochronous cycle too long\n");
1450 		reg_write(ohci, OHCI1394_LinkControlSet,
1451 			  OHCI1394_LinkControl_cycleMaster);
1452 	}
1453 
1454 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
1455 		/*
1456 		 * We need to clear this event bit in order to make
1457 		 * cycleMatch isochronous I/O work.  In theory we should
1458 		 * stop active cycleMatch iso contexts now and restart
1459 		 * them at least two cycles later.  (FIXME?)
1460 		 */
1461 		if (printk_ratelimit())
1462 			fw_notify("isochronous cycle inconsistent\n");
1463 	}
1464 
1465 	return IRQ_HANDLED;
1466 }
1467 
1468 static int software_reset(struct fw_ohci *ohci)
1469 {
1470 	int i;
1471 
1472 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1473 
1474 	for (i = 0; i < OHCI_LOOP_COUNT; i++) {
1475 		if ((reg_read(ohci, OHCI1394_HCControlSet) &
1476 		     OHCI1394_HCControl_softReset) == 0)
1477 			return 0;
1478 		msleep(1);
1479 	}
1480 
1481 	return -EBUSY;
1482 }
1483 
1484 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
1485 {
1486 	size_t size = length * 4;
1487 
1488 	memcpy(dest, src, size);
1489 	if (size < CONFIG_ROM_SIZE)
1490 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
1491 }
1492 
1493 static int ohci_enable(struct fw_card *card,
1494 		       const __be32 *config_rom, size_t length)
1495 {
1496 	struct fw_ohci *ohci = fw_ohci(card);
1497 	struct pci_dev *dev = to_pci_dev(card->device);
1498 	u32 lps;
1499 	int i;
1500 
1501 	if (software_reset(ohci)) {
1502 		fw_error("Failed to reset ohci card.\n");
1503 		return -EBUSY;
1504 	}
1505 
1506 	/*
1507 	 * Now enable LPS, which we need in order to start accessing
1508 	 * most of the registers.  In fact, on some cards (ALI M5251),
1509 	 * accessing registers in the SClk domain without LPS enabled
1510 	 * will lock up the machine.  Wait 50msec to make sure we have
1511 	 * full link enabled.  However, with some cards (well, at least
1512 	 * a JMicron PCIe card), we have to try again sometimes.
1513 	 */
1514 	reg_write(ohci, OHCI1394_HCControlSet,
1515 		  OHCI1394_HCControl_LPS |
1516 		  OHCI1394_HCControl_postedWriteEnable);
1517 	flush_writes(ohci);
1518 
1519 	for (lps = 0, i = 0; !lps && i < 3; i++) {
1520 		msleep(50);
1521 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
1522 		      OHCI1394_HCControl_LPS;
1523 	}
1524 
1525 	if (!lps) {
1526 		fw_error("Failed to set Link Power Status\n");
1527 		return -EIO;
1528 	}
1529 
1530 	reg_write(ohci, OHCI1394_HCControlClear,
1531 		  OHCI1394_HCControl_noByteSwapData);
1532 
1533 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
1534 	reg_write(ohci, OHCI1394_LinkControlClear,
1535 		  OHCI1394_LinkControl_rcvPhyPkt);
1536 	reg_write(ohci, OHCI1394_LinkControlSet,
1537 		  OHCI1394_LinkControl_rcvSelfID |
1538 		  OHCI1394_LinkControl_cycleTimerEnable |
1539 		  OHCI1394_LinkControl_cycleMaster);
1540 
1541 	reg_write(ohci, OHCI1394_ATRetries,
1542 		  OHCI1394_MAX_AT_REQ_RETRIES |
1543 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
1544 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8));
1545 
1546 	ar_context_run(&ohci->ar_request_ctx);
1547 	ar_context_run(&ohci->ar_response_ctx);
1548 
1549 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
1550 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
1551 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
1552 	reg_write(ohci, OHCI1394_IntMaskSet,
1553 		  OHCI1394_selfIDComplete |
1554 		  OHCI1394_RQPkt | OHCI1394_RSPkt |
1555 		  OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
1556 		  OHCI1394_isochRx | OHCI1394_isochTx |
1557 		  OHCI1394_postedWriteErr | OHCI1394_cycleTooLong |
1558 		  OHCI1394_cycleInconsistent | OHCI1394_regAccessFail |
1559 		  OHCI1394_masterIntEnable);
1560 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
1561 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_busReset);
1562 
1563 	/* Activate link_on bit and contender bit in our self ID packets.*/
1564 	if (ohci_update_phy_reg(card, 4, 0,
1565 				PHY_LINK_ACTIVE | PHY_CONTENDER) < 0)
1566 		return -EIO;
1567 
1568 	/*
1569 	 * When the link is not yet enabled, the atomic config rom
1570 	 * update mechanism described below in ohci_set_config_rom()
1571 	 * is not active.  We have to update ConfigRomHeader and
1572 	 * BusOptions manually, and the write to ConfigROMmap takes
1573 	 * effect immediately.  We tie this to the enabling of the
1574 	 * link, so we have a valid config rom before enabling - the
1575 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
1576 	 * values before enabling.
1577 	 *
1578 	 * However, when the ConfigROMmap is written, some controllers
1579 	 * always read back quadlets 0 and 2 from the config rom to
1580 	 * the ConfigRomHeader and BusOptions registers on bus reset.
1581 	 * They shouldn't do that in this initial case where the link
1582 	 * isn't enabled.  This means we have to use the same
1583 	 * workaround here, setting the bus header to 0 and then write
1584 	 * the right values in the bus reset tasklet.
1585 	 */
1586 
1587 	if (config_rom) {
1588 		ohci->next_config_rom =
1589 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1590 					   &ohci->next_config_rom_bus,
1591 					   GFP_KERNEL);
1592 		if (ohci->next_config_rom == NULL)
1593 			return -ENOMEM;
1594 
1595 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1596 	} else {
1597 		/*
1598 		 * In the suspend case, config_rom is NULL, which
1599 		 * means that we just reuse the old config rom.
1600 		 */
1601 		ohci->next_config_rom = ohci->config_rom;
1602 		ohci->next_config_rom_bus = ohci->config_rom_bus;
1603 	}
1604 
1605 	ohci->next_header = ohci->next_config_rom[0];
1606 	ohci->next_config_rom[0] = 0;
1607 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
1608 	reg_write(ohci, OHCI1394_BusOptions,
1609 		  be32_to_cpu(ohci->next_config_rom[2]));
1610 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
1611 
1612 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
1613 
1614 	if (request_irq(dev->irq, irq_handler,
1615 			IRQF_SHARED, ohci_driver_name, ohci)) {
1616 		fw_error("Failed to allocate shared interrupt %d.\n",
1617 			 dev->irq);
1618 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1619 				  ohci->config_rom, ohci->config_rom_bus);
1620 		return -EIO;
1621 	}
1622 
1623 	reg_write(ohci, OHCI1394_HCControlSet,
1624 		  OHCI1394_HCControl_linkEnable |
1625 		  OHCI1394_HCControl_BIBimageValid);
1626 	flush_writes(ohci);
1627 
1628 	/*
1629 	 * We are ready to go, initiate bus reset to finish the
1630 	 * initialization.
1631 	 */
1632 
1633 	fw_core_initiate_bus_reset(&ohci->card, 1);
1634 
1635 	return 0;
1636 }
1637 
1638 static int ohci_set_config_rom(struct fw_card *card,
1639 			       const __be32 *config_rom, size_t length)
1640 {
1641 	struct fw_ohci *ohci;
1642 	unsigned long flags;
1643 	int ret = -EBUSY;
1644 	__be32 *next_config_rom;
1645 	dma_addr_t uninitialized_var(next_config_rom_bus);
1646 
1647 	ohci = fw_ohci(card);
1648 
1649 	/*
1650 	 * When the OHCI controller is enabled, the config rom update
1651 	 * mechanism is a bit tricky, but easy enough to use.  See
1652 	 * section 5.5.6 in the OHCI specification.
1653 	 *
1654 	 * The OHCI controller caches the new config rom address in a
1655 	 * shadow register (ConfigROMmapNext) and needs a bus reset
1656 	 * for the changes to take place.  When the bus reset is
1657 	 * detected, the controller loads the new values for the
1658 	 * ConfigRomHeader and BusOptions registers from the specified
1659 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
1660 	 * shadow register. All automatically and atomically.
1661 	 *
1662 	 * Now, there's a twist to this story.  The automatic load of
1663 	 * ConfigRomHeader and BusOptions doesn't honor the
1664 	 * noByteSwapData bit, so with a be32 config rom, the
1665 	 * controller will load be32 values in to these registers
1666 	 * during the atomic update, even on litte endian
1667 	 * architectures.  The workaround we use is to put a 0 in the
1668 	 * header quadlet; 0 is endian agnostic and means that the
1669 	 * config rom isn't ready yet.  In the bus reset tasklet we
1670 	 * then set up the real values for the two registers.
1671 	 *
1672 	 * We use ohci->lock to avoid racing with the code that sets
1673 	 * ohci->next_config_rom to NULL (see bus_reset_tasklet).
1674 	 */
1675 
1676 	next_config_rom =
1677 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1678 				   &next_config_rom_bus, GFP_KERNEL);
1679 	if (next_config_rom == NULL)
1680 		return -ENOMEM;
1681 
1682 	spin_lock_irqsave(&ohci->lock, flags);
1683 
1684 	if (ohci->next_config_rom == NULL) {
1685 		ohci->next_config_rom = next_config_rom;
1686 		ohci->next_config_rom_bus = next_config_rom_bus;
1687 
1688 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1689 
1690 		ohci->next_header = config_rom[0];
1691 		ohci->next_config_rom[0] = 0;
1692 
1693 		reg_write(ohci, OHCI1394_ConfigROMmap,
1694 			  ohci->next_config_rom_bus);
1695 		ret = 0;
1696 	}
1697 
1698 	spin_unlock_irqrestore(&ohci->lock, flags);
1699 
1700 	/*
1701 	 * Now initiate a bus reset to have the changes take
1702 	 * effect. We clean up the old config rom memory and DMA
1703 	 * mappings in the bus reset tasklet, since the OHCI
1704 	 * controller could need to access it before the bus reset
1705 	 * takes effect.
1706 	 */
1707 	if (ret == 0)
1708 		fw_core_initiate_bus_reset(&ohci->card, 1);
1709 	else
1710 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1711 				  next_config_rom, next_config_rom_bus);
1712 
1713 	return ret;
1714 }
1715 
1716 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
1717 {
1718 	struct fw_ohci *ohci = fw_ohci(card);
1719 
1720 	at_context_transmit(&ohci->at_request_ctx, packet);
1721 }
1722 
1723 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
1724 {
1725 	struct fw_ohci *ohci = fw_ohci(card);
1726 
1727 	at_context_transmit(&ohci->at_response_ctx, packet);
1728 }
1729 
1730 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
1731 {
1732 	struct fw_ohci *ohci = fw_ohci(card);
1733 	struct context *ctx = &ohci->at_request_ctx;
1734 	struct driver_data *driver_data = packet->driver_data;
1735 	int ret = -ENOENT;
1736 
1737 	tasklet_disable(&ctx->tasklet);
1738 
1739 	if (packet->ack != 0)
1740 		goto out;
1741 
1742 	if (packet->payload_mapped)
1743 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1744 				 packet->payload_length, DMA_TO_DEVICE);
1745 
1746 	log_ar_at_event('T', packet->speed, packet->header, 0x20);
1747 	driver_data->packet = NULL;
1748 	packet->ack = RCODE_CANCELLED;
1749 	packet->callback(packet, &ohci->card, packet->ack);
1750 	ret = 0;
1751  out:
1752 	tasklet_enable(&ctx->tasklet);
1753 
1754 	return ret;
1755 }
1756 
1757 static int ohci_enable_phys_dma(struct fw_card *card,
1758 				int node_id, int generation)
1759 {
1760 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1761 	return 0;
1762 #else
1763 	struct fw_ohci *ohci = fw_ohci(card);
1764 	unsigned long flags;
1765 	int n, ret = 0;
1766 
1767 	/*
1768 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
1769 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
1770 	 */
1771 
1772 	spin_lock_irqsave(&ohci->lock, flags);
1773 
1774 	if (ohci->generation != generation) {
1775 		ret = -ESTALE;
1776 		goto out;
1777 	}
1778 
1779 	/*
1780 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
1781 	 * enabled for _all_ nodes on remote buses.
1782 	 */
1783 
1784 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
1785 	if (n < 32)
1786 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
1787 	else
1788 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
1789 
1790 	flush_writes(ohci);
1791  out:
1792 	spin_unlock_irqrestore(&ohci->lock, flags);
1793 
1794 	return ret;
1795 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
1796 }
1797 
1798 static u32 cycle_timer_ticks(u32 cycle_timer)
1799 {
1800 	u32 ticks;
1801 
1802 	ticks = cycle_timer & 0xfff;
1803 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1804 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1805 
1806 	return ticks;
1807 }
1808 
1809 /*
1810  * Some controllers exhibit one or more of the following bugs when updating the
1811  * iso cycle timer register:
1812  *  - When the lowest six bits are wrapping around to zero, a read that happens
1813  *    at the same time will return garbage in the lowest ten bits.
1814  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1815  *    not incremented for about 60 ns.
1816  *  - Occasionally, the entire register reads zero.
1817  *
1818  * To catch these, we read the register three times and ensure that the
1819  * difference between each two consecutive reads is approximately the same, i.e.
1820  * less than twice the other.  Furthermore, any negative difference indicates an
1821  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1822  * execute, so we have enough precision to compute the ratio of the differences.)
1823  */
1824 static u32 ohci_get_cycle_time(struct fw_card *card)
1825 {
1826 	struct fw_ohci *ohci = fw_ohci(card);
1827 	u32 c0, c1, c2;
1828 	u32 t0, t1, t2;
1829 	s32 diff01, diff12;
1830 	int i;
1831 
1832 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1833 
1834 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1835 		i = 0;
1836 		c1 = c2;
1837 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1838 		do {
1839 			c0 = c1;
1840 			c1 = c2;
1841 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1842 			t0 = cycle_timer_ticks(c0);
1843 			t1 = cycle_timer_ticks(c1);
1844 			t2 = cycle_timer_ticks(c2);
1845 			diff01 = t1 - t0;
1846 			diff12 = t2 - t1;
1847 		} while ((diff01 <= 0 || diff12 <= 0 ||
1848 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1849 			 && i++ < 20);
1850 	}
1851 
1852 	return c2;
1853 }
1854 
1855 static void copy_iso_headers(struct iso_context *ctx, void *p)
1856 {
1857 	int i = ctx->header_length;
1858 
1859 	if (i + ctx->base.header_size > PAGE_SIZE)
1860 		return;
1861 
1862 	/*
1863 	 * The iso header is byteswapped to little endian by
1864 	 * the controller, but the remaining header quadlets
1865 	 * are big endian.  We want to present all the headers
1866 	 * as big endian, so we have to swap the first quadlet.
1867 	 */
1868 	if (ctx->base.header_size > 0)
1869 		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
1870 	if (ctx->base.header_size > 4)
1871 		*(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
1872 	if (ctx->base.header_size > 8)
1873 		memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
1874 	ctx->header_length += ctx->base.header_size;
1875 }
1876 
1877 static int handle_ir_packet_per_buffer(struct context *context,
1878 				       struct descriptor *d,
1879 				       struct descriptor *last)
1880 {
1881 	struct iso_context *ctx =
1882 		container_of(context, struct iso_context, context);
1883 	struct descriptor *pd;
1884 	__le32 *ir_header;
1885 	void *p;
1886 
1887 	for (pd = d; pd <= last; pd++) {
1888 		if (pd->transfer_status)
1889 			break;
1890 	}
1891 	if (pd > last)
1892 		/* Descriptor(s) not done yet, stop iteration */
1893 		return 0;
1894 
1895 	p = last + 1;
1896 	copy_iso_headers(ctx, p);
1897 
1898 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
1899 		ir_header = (__le32 *) p;
1900 		ctx->base.callback(&ctx->base,
1901 				   le32_to_cpu(ir_header[0]) & 0xffff,
1902 				   ctx->header_length, ctx->header,
1903 				   ctx->base.callback_data);
1904 		ctx->header_length = 0;
1905 	}
1906 
1907 	return 1;
1908 }
1909 
1910 static int handle_it_packet(struct context *context,
1911 			    struct descriptor *d,
1912 			    struct descriptor *last)
1913 {
1914 	struct iso_context *ctx =
1915 		container_of(context, struct iso_context, context);
1916 	int i;
1917 	struct descriptor *pd;
1918 
1919 	for (pd = d; pd <= last; pd++)
1920 		if (pd->transfer_status)
1921 			break;
1922 	if (pd > last)
1923 		/* Descriptor(s) not done yet, stop iteration */
1924 		return 0;
1925 
1926 	i = ctx->header_length;
1927 	if (i + 4 < PAGE_SIZE) {
1928 		/* Present this value as big-endian to match the receive code */
1929 		*(__be32 *)(ctx->header + i) = cpu_to_be32(
1930 				((u32)le16_to_cpu(pd->transfer_status) << 16) |
1931 				le16_to_cpu(pd->res_count));
1932 		ctx->header_length += 4;
1933 	}
1934 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
1935 		ctx->base.callback(&ctx->base, le16_to_cpu(last->res_count),
1936 				   ctx->header_length, ctx->header,
1937 				   ctx->base.callback_data);
1938 		ctx->header_length = 0;
1939 	}
1940 	return 1;
1941 }
1942 
1943 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
1944 				int type, int channel, size_t header_size)
1945 {
1946 	struct fw_ohci *ohci = fw_ohci(card);
1947 	struct iso_context *ctx, *list;
1948 	descriptor_callback_t callback;
1949 	u64 *channels, dont_care = ~0ULL;
1950 	u32 *mask, regs;
1951 	unsigned long flags;
1952 	int index, ret = -ENOMEM;
1953 
1954 	if (type == FW_ISO_CONTEXT_TRANSMIT) {
1955 		channels = &dont_care;
1956 		mask = &ohci->it_context_mask;
1957 		list = ohci->it_context_list;
1958 		callback = handle_it_packet;
1959 	} else {
1960 		channels = &ohci->ir_context_channels;
1961 		mask = &ohci->ir_context_mask;
1962 		list = ohci->ir_context_list;
1963 		callback = handle_ir_packet_per_buffer;
1964 	}
1965 
1966 	spin_lock_irqsave(&ohci->lock, flags);
1967 	index = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
1968 	if (index >= 0) {
1969 		*channels &= ~(1ULL << channel);
1970 		*mask &= ~(1 << index);
1971 	}
1972 	spin_unlock_irqrestore(&ohci->lock, flags);
1973 
1974 	if (index < 0)
1975 		return ERR_PTR(-EBUSY);
1976 
1977 	if (type == FW_ISO_CONTEXT_TRANSMIT)
1978 		regs = OHCI1394_IsoXmitContextBase(index);
1979 	else
1980 		regs = OHCI1394_IsoRcvContextBase(index);
1981 
1982 	ctx = &list[index];
1983 	memset(ctx, 0, sizeof(*ctx));
1984 	ctx->header_length = 0;
1985 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
1986 	if (ctx->header == NULL)
1987 		goto out;
1988 
1989 	ret = context_init(&ctx->context, ohci, regs, callback);
1990 	if (ret < 0)
1991 		goto out_with_header;
1992 
1993 	return &ctx->base;
1994 
1995  out_with_header:
1996 	free_page((unsigned long)ctx->header);
1997  out:
1998 	spin_lock_irqsave(&ohci->lock, flags);
1999 	*mask |= 1 << index;
2000 	spin_unlock_irqrestore(&ohci->lock, flags);
2001 
2002 	return ERR_PTR(ret);
2003 }
2004 
2005 static int ohci_start_iso(struct fw_iso_context *base,
2006 			  s32 cycle, u32 sync, u32 tags)
2007 {
2008 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2009 	struct fw_ohci *ohci = ctx->context.ohci;
2010 	u32 control, match;
2011 	int index;
2012 
2013 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2014 		index = ctx - ohci->it_context_list;
2015 		match = 0;
2016 		if (cycle >= 0)
2017 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
2018 				(cycle & 0x7fff) << 16;
2019 
2020 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
2021 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
2022 		context_run(&ctx->context, match);
2023 	} else {
2024 		index = ctx - ohci->ir_context_list;
2025 		control = IR_CONTEXT_ISOCH_HEADER;
2026 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
2027 		if (cycle >= 0) {
2028 			match |= (cycle & 0x07fff) << 12;
2029 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
2030 		}
2031 
2032 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2033 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2034 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2035 		context_run(&ctx->context, control);
2036 	}
2037 
2038 	return 0;
2039 }
2040 
2041 static int ohci_stop_iso(struct fw_iso_context *base)
2042 {
2043 	struct fw_ohci *ohci = fw_ohci(base->card);
2044 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2045 	int index;
2046 
2047 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2048 		index = ctx - ohci->it_context_list;
2049 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2050 	} else {
2051 		index = ctx - ohci->ir_context_list;
2052 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2053 	}
2054 	flush_writes(ohci);
2055 	context_stop(&ctx->context);
2056 
2057 	return 0;
2058 }
2059 
2060 static void ohci_free_iso_context(struct fw_iso_context *base)
2061 {
2062 	struct fw_ohci *ohci = fw_ohci(base->card);
2063 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2064 	unsigned long flags;
2065 	int index;
2066 
2067 	ohci_stop_iso(base);
2068 	context_release(&ctx->context);
2069 	free_page((unsigned long)ctx->header);
2070 
2071 	spin_lock_irqsave(&ohci->lock, flags);
2072 
2073 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2074 		index = ctx - ohci->it_context_list;
2075 		ohci->it_context_mask |= 1 << index;
2076 	} else {
2077 		index = ctx - ohci->ir_context_list;
2078 		ohci->ir_context_mask |= 1 << index;
2079 		ohci->ir_context_channels |= 1ULL << base->channel;
2080 	}
2081 
2082 	spin_unlock_irqrestore(&ohci->lock, flags);
2083 }
2084 
2085 static int ohci_queue_iso_transmit(struct fw_iso_context *base,
2086 				   struct fw_iso_packet *packet,
2087 				   struct fw_iso_buffer *buffer,
2088 				   unsigned long payload)
2089 {
2090 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2091 	struct descriptor *d, *last, *pd;
2092 	struct fw_iso_packet *p;
2093 	__le32 *header;
2094 	dma_addr_t d_bus, page_bus;
2095 	u32 z, header_z, payload_z, irq;
2096 	u32 payload_index, payload_end_index, next_page_index;
2097 	int page, end_page, i, length, offset;
2098 
2099 	p = packet;
2100 	payload_index = payload;
2101 
2102 	if (p->skip)
2103 		z = 1;
2104 	else
2105 		z = 2;
2106 	if (p->header_length > 0)
2107 		z++;
2108 
2109 	/* Determine the first page the payload isn't contained in. */
2110 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2111 	if (p->payload_length > 0)
2112 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
2113 	else
2114 		payload_z = 0;
2115 
2116 	z += payload_z;
2117 
2118 	/* Get header size in number of descriptors. */
2119 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2120 
2121 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2122 	if (d == NULL)
2123 		return -ENOMEM;
2124 
2125 	if (!p->skip) {
2126 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2127 		d[0].req_count = cpu_to_le16(8);
2128 		/*
2129 		 * Link the skip address to this descriptor itself.  This causes
2130 		 * a context to skip a cycle whenever lost cycles or FIFO
2131 		 * overruns occur, without dropping the data.  The application
2132 		 * should then decide whether this is an error condition or not.
2133 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
2134 		 */
2135 		d[0].branch_address = cpu_to_le32(d_bus | z);
2136 
2137 		header = (__le32 *) &d[1];
2138 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2139 					IT_HEADER_TAG(p->tag) |
2140 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2141 					IT_HEADER_CHANNEL(ctx->base.channel) |
2142 					IT_HEADER_SPEED(ctx->base.speed));
2143 		header[1] =
2144 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2145 							  p->payload_length));
2146 	}
2147 
2148 	if (p->header_length > 0) {
2149 		d[2].req_count    = cpu_to_le16(p->header_length);
2150 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2151 		memcpy(&d[z], p->header, p->header_length);
2152 	}
2153 
2154 	pd = d + z - payload_z;
2155 	payload_end_index = payload_index + p->payload_length;
2156 	for (i = 0; i < payload_z; i++) {
2157 		page               = payload_index >> PAGE_SHIFT;
2158 		offset             = payload_index & ~PAGE_MASK;
2159 		next_page_index    = (page + 1) << PAGE_SHIFT;
2160 		length             =
2161 			min(next_page_index, payload_end_index) - payload_index;
2162 		pd[i].req_count    = cpu_to_le16(length);
2163 
2164 		page_bus = page_private(buffer->pages[page]);
2165 		pd[i].data_address = cpu_to_le32(page_bus + offset);
2166 
2167 		payload_index += length;
2168 	}
2169 
2170 	if (p->interrupt)
2171 		irq = DESCRIPTOR_IRQ_ALWAYS;
2172 	else
2173 		irq = DESCRIPTOR_NO_IRQ;
2174 
2175 	last = z == 2 ? d : d + z - 1;
2176 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2177 				     DESCRIPTOR_STATUS |
2178 				     DESCRIPTOR_BRANCH_ALWAYS |
2179 				     irq);
2180 
2181 	context_append(&ctx->context, d, z, header_z);
2182 
2183 	return 0;
2184 }
2185 
2186 static int ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base,
2187 					struct fw_iso_packet *packet,
2188 					struct fw_iso_buffer *buffer,
2189 					unsigned long payload)
2190 {
2191 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2192 	struct descriptor *d, *pd;
2193 	struct fw_iso_packet *p = packet;
2194 	dma_addr_t d_bus, page_bus;
2195 	u32 z, header_z, rest;
2196 	int i, j, length;
2197 	int page, offset, packet_count, header_size, payload_per_buffer;
2198 
2199 	/*
2200 	 * The OHCI controller puts the isochronous header and trailer in the
2201 	 * buffer, so we need at least 8 bytes.
2202 	 */
2203 	packet_count = p->header_length / ctx->base.header_size;
2204 	header_size  = max(ctx->base.header_size, (size_t)8);
2205 
2206 	/* Get header size in number of descriptors. */
2207 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2208 	page     = payload >> PAGE_SHIFT;
2209 	offset   = payload & ~PAGE_MASK;
2210 	payload_per_buffer = p->payload_length / packet_count;
2211 
2212 	for (i = 0; i < packet_count; i++) {
2213 		/* d points to the header descriptor */
2214 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
2215 		d = context_get_descriptors(&ctx->context,
2216 				z + header_z, &d_bus);
2217 		if (d == NULL)
2218 			return -ENOMEM;
2219 
2220 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
2221 					      DESCRIPTOR_INPUT_MORE);
2222 		if (p->skip && i == 0)
2223 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2224 		d->req_count    = cpu_to_le16(header_size);
2225 		d->res_count    = d->req_count;
2226 		d->transfer_status = 0;
2227 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
2228 
2229 		rest = payload_per_buffer;
2230 		pd = d;
2231 		for (j = 1; j < z; j++) {
2232 			pd++;
2233 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2234 						  DESCRIPTOR_INPUT_MORE);
2235 
2236 			if (offset + rest < PAGE_SIZE)
2237 				length = rest;
2238 			else
2239 				length = PAGE_SIZE - offset;
2240 			pd->req_count = cpu_to_le16(length);
2241 			pd->res_count = pd->req_count;
2242 			pd->transfer_status = 0;
2243 
2244 			page_bus = page_private(buffer->pages[page]);
2245 			pd->data_address = cpu_to_le32(page_bus + offset);
2246 
2247 			offset = (offset + length) & ~PAGE_MASK;
2248 			rest -= length;
2249 			if (offset == 0)
2250 				page++;
2251 		}
2252 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2253 					  DESCRIPTOR_INPUT_LAST |
2254 					  DESCRIPTOR_BRANCH_ALWAYS);
2255 		if (p->interrupt && i == packet_count - 1)
2256 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2257 
2258 		context_append(&ctx->context, d, z, header_z);
2259 	}
2260 
2261 	return 0;
2262 }
2263 
2264 static int ohci_queue_iso(struct fw_iso_context *base,
2265 			  struct fw_iso_packet *packet,
2266 			  struct fw_iso_buffer *buffer,
2267 			  unsigned long payload)
2268 {
2269 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2270 	unsigned long flags;
2271 	int ret;
2272 
2273 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
2274 	if (base->type == FW_ISO_CONTEXT_TRANSMIT)
2275 		ret = ohci_queue_iso_transmit(base, packet, buffer, payload);
2276 	else
2277 		ret = ohci_queue_iso_receive_packet_per_buffer(base, packet,
2278 							buffer, payload);
2279 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
2280 
2281 	return ret;
2282 }
2283 
2284 static const struct fw_card_driver ohci_driver = {
2285 	.enable			= ohci_enable,
2286 	.update_phy_reg		= ohci_update_phy_reg,
2287 	.set_config_rom		= ohci_set_config_rom,
2288 	.send_request		= ohci_send_request,
2289 	.send_response		= ohci_send_response,
2290 	.cancel_packet		= ohci_cancel_packet,
2291 	.enable_phys_dma	= ohci_enable_phys_dma,
2292 	.get_cycle_time		= ohci_get_cycle_time,
2293 
2294 	.allocate_iso_context	= ohci_allocate_iso_context,
2295 	.free_iso_context	= ohci_free_iso_context,
2296 	.queue_iso		= ohci_queue_iso,
2297 	.start_iso		= ohci_start_iso,
2298 	.stop_iso		= ohci_stop_iso,
2299 };
2300 
2301 #ifdef CONFIG_PPC_PMAC
2302 static void ohci_pmac_on(struct pci_dev *dev)
2303 {
2304 	if (machine_is(powermac)) {
2305 		struct device_node *ofn = pci_device_to_OF_node(dev);
2306 
2307 		if (ofn) {
2308 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
2309 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
2310 		}
2311 	}
2312 }
2313 
2314 static void ohci_pmac_off(struct pci_dev *dev)
2315 {
2316 	if (machine_is(powermac)) {
2317 		struct device_node *ofn = pci_device_to_OF_node(dev);
2318 
2319 		if (ofn) {
2320 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
2321 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
2322 		}
2323 	}
2324 }
2325 #else
2326 #define ohci_pmac_on(dev)
2327 #define ohci_pmac_off(dev)
2328 #endif /* CONFIG_PPC_PMAC */
2329 
2330 static int __devinit pci_probe(struct pci_dev *dev,
2331 			       const struct pci_device_id *ent)
2332 {
2333 	struct fw_ohci *ohci;
2334 	u32 bus_options, max_receive, link_speed, version;
2335 	u64 guid;
2336 	int i, err, n_ir, n_it;
2337 	size_t size;
2338 
2339 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
2340 	if (ohci == NULL) {
2341 		err = -ENOMEM;
2342 		goto fail;
2343 	}
2344 
2345 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
2346 
2347 	ohci_pmac_on(dev);
2348 
2349 	err = pci_enable_device(dev);
2350 	if (err) {
2351 		fw_error("Failed to enable OHCI hardware\n");
2352 		goto fail_free;
2353 	}
2354 
2355 	pci_set_master(dev);
2356 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
2357 	pci_set_drvdata(dev, ohci);
2358 
2359 	spin_lock_init(&ohci->lock);
2360 
2361 	tasklet_init(&ohci->bus_reset_tasklet,
2362 		     bus_reset_tasklet, (unsigned long)ohci);
2363 
2364 	err = pci_request_region(dev, 0, ohci_driver_name);
2365 	if (err) {
2366 		fw_error("MMIO resource unavailable\n");
2367 		goto fail_disable;
2368 	}
2369 
2370 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
2371 	if (ohci->registers == NULL) {
2372 		fw_error("Failed to remap registers\n");
2373 		err = -ENXIO;
2374 		goto fail_iomem;
2375 	}
2376 
2377 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
2378 		if (ohci_quirks[i].vendor == dev->vendor &&
2379 		    (ohci_quirks[i].device == dev->device ||
2380 		     ohci_quirks[i].device == (unsigned short)PCI_ANY_ID)) {
2381 			ohci->quirks = ohci_quirks[i].flags;
2382 			break;
2383 		}
2384 	if (param_quirks)
2385 		ohci->quirks = param_quirks;
2386 
2387 	ar_context_init(&ohci->ar_request_ctx, ohci,
2388 			OHCI1394_AsReqRcvContextControlSet);
2389 
2390 	ar_context_init(&ohci->ar_response_ctx, ohci,
2391 			OHCI1394_AsRspRcvContextControlSet);
2392 
2393 	context_init(&ohci->at_request_ctx, ohci,
2394 		     OHCI1394_AsReqTrContextControlSet, handle_at_packet);
2395 
2396 	context_init(&ohci->at_response_ctx, ohci,
2397 		     OHCI1394_AsRspTrContextControlSet, handle_at_packet);
2398 
2399 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
2400 	ohci->ir_context_channels = ~0ULL;
2401 	ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
2402 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
2403 	n_ir = hweight32(ohci->ir_context_mask);
2404 	size = sizeof(struct iso_context) * n_ir;
2405 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
2406 
2407 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
2408 	ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
2409 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
2410 	n_it = hweight32(ohci->it_context_mask);
2411 	size = sizeof(struct iso_context) * n_it;
2412 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
2413 
2414 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
2415 		err = -ENOMEM;
2416 		goto fail_contexts;
2417 	}
2418 
2419 	/* self-id dma buffer allocation */
2420 	ohci->self_id_cpu = dma_alloc_coherent(ohci->card.device,
2421 					       SELF_ID_BUF_SIZE,
2422 					       &ohci->self_id_bus,
2423 					       GFP_KERNEL);
2424 	if (ohci->self_id_cpu == NULL) {
2425 		err = -ENOMEM;
2426 		goto fail_contexts;
2427 	}
2428 
2429 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
2430 	max_receive = (bus_options >> 12) & 0xf;
2431 	link_speed = bus_options & 0x7;
2432 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
2433 		reg_read(ohci, OHCI1394_GUIDLo);
2434 
2435 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
2436 	if (err)
2437 		goto fail_self_id;
2438 
2439 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2440 	fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
2441 		  "%d IR + %d IT contexts, quirks 0x%x\n",
2442 		  dev_name(&dev->dev), version >> 16, version & 0xff,
2443 		  n_ir, n_it, ohci->quirks);
2444 
2445 	return 0;
2446 
2447  fail_self_id:
2448 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2449 			  ohci->self_id_cpu, ohci->self_id_bus);
2450  fail_contexts:
2451 	kfree(ohci->ir_context_list);
2452 	kfree(ohci->it_context_list);
2453 	context_release(&ohci->at_response_ctx);
2454 	context_release(&ohci->at_request_ctx);
2455 	ar_context_release(&ohci->ar_response_ctx);
2456 	ar_context_release(&ohci->ar_request_ctx);
2457 	pci_iounmap(dev, ohci->registers);
2458  fail_iomem:
2459 	pci_release_region(dev, 0);
2460  fail_disable:
2461 	pci_disable_device(dev);
2462  fail_free:
2463 	kfree(&ohci->card);
2464 	ohci_pmac_off(dev);
2465  fail:
2466 	if (err == -ENOMEM)
2467 		fw_error("Out of memory\n");
2468 
2469 	return err;
2470 }
2471 
2472 static void pci_remove(struct pci_dev *dev)
2473 {
2474 	struct fw_ohci *ohci;
2475 
2476 	ohci = pci_get_drvdata(dev);
2477 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2478 	flush_writes(ohci);
2479 	fw_core_remove_card(&ohci->card);
2480 
2481 	/*
2482 	 * FIXME: Fail all pending packets here, now that the upper
2483 	 * layers can't queue any more.
2484 	 */
2485 
2486 	software_reset(ohci);
2487 	free_irq(dev->irq, ohci);
2488 
2489 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
2490 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2491 				  ohci->next_config_rom, ohci->next_config_rom_bus);
2492 	if (ohci->config_rom)
2493 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2494 				  ohci->config_rom, ohci->config_rom_bus);
2495 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2496 			  ohci->self_id_cpu, ohci->self_id_bus);
2497 	ar_context_release(&ohci->ar_request_ctx);
2498 	ar_context_release(&ohci->ar_response_ctx);
2499 	context_release(&ohci->at_request_ctx);
2500 	context_release(&ohci->at_response_ctx);
2501 	kfree(ohci->it_context_list);
2502 	kfree(ohci->ir_context_list);
2503 	pci_iounmap(dev, ohci->registers);
2504 	pci_release_region(dev, 0);
2505 	pci_disable_device(dev);
2506 	kfree(&ohci->card);
2507 	ohci_pmac_off(dev);
2508 
2509 	fw_notify("Removed fw-ohci device.\n");
2510 }
2511 
2512 #ifdef CONFIG_PM
2513 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
2514 {
2515 	struct fw_ohci *ohci = pci_get_drvdata(dev);
2516 	int err;
2517 
2518 	software_reset(ohci);
2519 	free_irq(dev->irq, ohci);
2520 	err = pci_save_state(dev);
2521 	if (err) {
2522 		fw_error("pci_save_state failed\n");
2523 		return err;
2524 	}
2525 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
2526 	if (err)
2527 		fw_error("pci_set_power_state failed with %d\n", err);
2528 	ohci_pmac_off(dev);
2529 
2530 	return 0;
2531 }
2532 
2533 static int pci_resume(struct pci_dev *dev)
2534 {
2535 	struct fw_ohci *ohci = pci_get_drvdata(dev);
2536 	int err;
2537 
2538 	ohci_pmac_on(dev);
2539 	pci_set_power_state(dev, PCI_D0);
2540 	pci_restore_state(dev);
2541 	err = pci_enable_device(dev);
2542 	if (err) {
2543 		fw_error("pci_enable_device failed\n");
2544 		return err;
2545 	}
2546 
2547 	return ohci_enable(&ohci->card, NULL, 0);
2548 }
2549 #endif
2550 
2551 static const struct pci_device_id pci_table[] = {
2552 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
2553 	{ }
2554 };
2555 
2556 MODULE_DEVICE_TABLE(pci, pci_table);
2557 
2558 static struct pci_driver fw_ohci_pci_driver = {
2559 	.name		= ohci_driver_name,
2560 	.id_table	= pci_table,
2561 	.probe		= pci_probe,
2562 	.remove		= pci_remove,
2563 #ifdef CONFIG_PM
2564 	.resume		= pci_resume,
2565 	.suspend	= pci_suspend,
2566 #endif
2567 };
2568 
2569 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
2570 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
2571 MODULE_LICENSE("GPL");
2572 
2573 /* Provide a module alias so root-on-sbp2 initrds don't break. */
2574 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
2575 MODULE_ALIAS("ohci1394");
2576 #endif
2577 
2578 static int __init fw_ohci_init(void)
2579 {
2580 	return pci_register_driver(&fw_ohci_pci_driver);
2581 }
2582 
2583 static void __exit fw_ohci_cleanup(void)
2584 {
2585 	pci_unregister_driver(&fw_ohci_pci_driver);
2586 }
2587 
2588 module_init(fw_ohci_init);
2589 module_exit(fw_ohci_cleanup);
2590