xref: /linux/drivers/firewire/ohci.c (revision a115bc070b1fc57ab23f3972401425927b5b465c)
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/gfp.h>
28 #include <linux/init.h>
29 #include <linux/interrupt.h>
30 #include <linux/io.h>
31 #include <linux/kernel.h>
32 #include <linux/list.h>
33 #include <linux/mm.h>
34 #include <linux/module.h>
35 #include <linux/moduleparam.h>
36 #include <linux/pci.h>
37 #include <linux/pci_ids.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 QUIRK_CYCLE_TIMER		1
235 #define QUIRK_RESET_PACKET		2
236 #define QUIRK_BE_HEADERS		4
237 
238 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
239 static const struct {
240 	unsigned short vendor, device, flags;
241 } ohci_quirks[] = {
242 	{PCI_VENDOR_ID_TI,	PCI_ANY_ID,	QUIRK_RESET_PACKET},
243 	{PCI_VENDOR_ID_AL,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
244 	{PCI_VENDOR_ID_NEC,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
245 	{PCI_VENDOR_ID_VIA,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
246 	{PCI_VENDOR_ID_APPLE,	PCI_DEVICE_ID_APPLE_UNI_N_FW, QUIRK_BE_HEADERS},
247 };
248 
249 /* This overrides anything that was found in ohci_quirks[]. */
250 static int param_quirks;
251 module_param_named(quirks, param_quirks, int, 0644);
252 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
253 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
254 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
255 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
256 	")");
257 
258 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
259 
260 #define OHCI_PARAM_DEBUG_AT_AR		1
261 #define OHCI_PARAM_DEBUG_SELFIDS	2
262 #define OHCI_PARAM_DEBUG_IRQS		4
263 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
264 
265 static int param_debug;
266 module_param_named(debug, param_debug, int, 0644);
267 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
268 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
269 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
270 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
271 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
272 	", or a combination, or all = -1)");
273 
274 static void log_irqs(u32 evt)
275 {
276 	if (likely(!(param_debug &
277 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
278 		return;
279 
280 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
281 	    !(evt & OHCI1394_busReset))
282 		return;
283 
284 	fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
285 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
286 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
287 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
288 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
289 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
290 	    evt & OHCI1394_isochRx		? " IR"			: "",
291 	    evt & OHCI1394_isochTx		? " IT"			: "",
292 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
293 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
294 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
295 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
296 	    evt & OHCI1394_busReset		? " busReset"		: "",
297 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
298 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
299 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
300 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
301 		    OHCI1394_cycleTooLong | OHCI1394_cycleInconsistent |
302 		    OHCI1394_regAccessFail | OHCI1394_busReset)
303 						? " ?"			: "");
304 }
305 
306 static const char *speed[] = {
307 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
308 };
309 static const char *power[] = {
310 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
311 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
312 };
313 static const char port[] = { '.', '-', 'p', 'c', };
314 
315 static char _p(u32 *s, int shift)
316 {
317 	return port[*s >> shift & 3];
318 }
319 
320 static void log_selfids(int node_id, int generation, int self_id_count, u32 *s)
321 {
322 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
323 		return;
324 
325 	fw_notify("%d selfIDs, generation %d, local node ID %04x\n",
326 		  self_id_count, generation, node_id);
327 
328 	for (; self_id_count--; ++s)
329 		if ((*s & 1 << 23) == 0)
330 			fw_notify("selfID 0: %08x, phy %d [%c%c%c] "
331 			    "%s gc=%d %s %s%s%s\n",
332 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
333 			    speed[*s >> 14 & 3], *s >> 16 & 63,
334 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
335 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
336 		else
337 			fw_notify("selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
338 			    *s, *s >> 24 & 63,
339 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
340 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
341 }
342 
343 static const char *evts[] = {
344 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
345 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
346 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
347 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
348 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
349 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
350 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
351 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
352 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
353 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
354 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
355 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
356 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
357 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
358 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
359 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
360 	[0x20] = "pending/cancelled",
361 };
362 static const char *tcodes[] = {
363 	[0x0] = "QW req",		[0x1] = "BW req",
364 	[0x2] = "W resp",		[0x3] = "-reserved-",
365 	[0x4] = "QR req",		[0x5] = "BR req",
366 	[0x6] = "QR resp",		[0x7] = "BR resp",
367 	[0x8] = "cycle start",		[0x9] = "Lk req",
368 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
369 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
370 	[0xe] = "link internal",	[0xf] = "-reserved-",
371 };
372 static const char *phys[] = {
373 	[0x0] = "phy config packet",	[0x1] = "link-on packet",
374 	[0x2] = "self-id packet",	[0x3] = "-reserved-",
375 };
376 
377 static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
378 {
379 	int tcode = header[0] >> 4 & 0xf;
380 	char specific[12];
381 
382 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
383 		return;
384 
385 	if (unlikely(evt >= ARRAY_SIZE(evts)))
386 			evt = 0x1f;
387 
388 	if (evt == OHCI1394_evt_bus_reset) {
389 		fw_notify("A%c evt_bus_reset, generation %d\n",
390 		    dir, (header[2] >> 16) & 0xff);
391 		return;
392 	}
393 
394 	if (header[0] == ~header[1]) {
395 		fw_notify("A%c %s, %s, %08x\n",
396 		    dir, evts[evt], phys[header[0] >> 30 & 0x3], header[0]);
397 		return;
398 	}
399 
400 	switch (tcode) {
401 	case 0x0: case 0x6: case 0x8:
402 		snprintf(specific, sizeof(specific), " = %08x",
403 			 be32_to_cpu((__force __be32)header[3]));
404 		break;
405 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
406 		snprintf(specific, sizeof(specific), " %x,%x",
407 			 header[3] >> 16, header[3] & 0xffff);
408 		break;
409 	default:
410 		specific[0] = '\0';
411 	}
412 
413 	switch (tcode) {
414 	case 0xe: case 0xa:
415 		fw_notify("A%c %s, %s\n", dir, evts[evt], tcodes[tcode]);
416 		break;
417 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
418 		fw_notify("A%c spd %x tl %02x, "
419 		    "%04x -> %04x, %s, "
420 		    "%s, %04x%08x%s\n",
421 		    dir, speed, header[0] >> 10 & 0x3f,
422 		    header[1] >> 16, header[0] >> 16, evts[evt],
423 		    tcodes[tcode], header[1] & 0xffff, header[2], specific);
424 		break;
425 	default:
426 		fw_notify("A%c spd %x tl %02x, "
427 		    "%04x -> %04x, %s, "
428 		    "%s%s\n",
429 		    dir, speed, header[0] >> 10 & 0x3f,
430 		    header[1] >> 16, header[0] >> 16, evts[evt],
431 		    tcodes[tcode], specific);
432 	}
433 }
434 
435 #else
436 
437 #define log_irqs(evt)
438 #define log_selfids(node_id, generation, self_id_count, sid)
439 #define log_ar_at_event(dir, speed, header, evt)
440 
441 #endif /* CONFIG_FIREWIRE_OHCI_DEBUG */
442 
443 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
444 {
445 	writel(data, ohci->registers + offset);
446 }
447 
448 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
449 {
450 	return readl(ohci->registers + offset);
451 }
452 
453 static inline void flush_writes(const struct fw_ohci *ohci)
454 {
455 	/* Do a dummy read to flush writes. */
456 	reg_read(ohci, OHCI1394_Version);
457 }
458 
459 static int ohci_update_phy_reg(struct fw_card *card, int addr,
460 			       int clear_bits, int set_bits)
461 {
462 	struct fw_ohci *ohci = fw_ohci(card);
463 	u32 val, old;
464 
465 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
466 	flush_writes(ohci);
467 	msleep(2);
468 	val = reg_read(ohci, OHCI1394_PhyControl);
469 	if ((val & OHCI1394_PhyControl_ReadDone) == 0) {
470 		fw_error("failed to set phy reg bits.\n");
471 		return -EBUSY;
472 	}
473 
474 	old = OHCI1394_PhyControl_ReadData(val);
475 	old = (old & ~clear_bits) | set_bits;
476 	reg_write(ohci, OHCI1394_PhyControl,
477 		  OHCI1394_PhyControl_Write(addr, old));
478 
479 	return 0;
480 }
481 
482 static int ar_context_add_page(struct ar_context *ctx)
483 {
484 	struct device *dev = ctx->ohci->card.device;
485 	struct ar_buffer *ab;
486 	dma_addr_t uninitialized_var(ab_bus);
487 	size_t offset;
488 
489 	ab = dma_alloc_coherent(dev, PAGE_SIZE, &ab_bus, GFP_ATOMIC);
490 	if (ab == NULL)
491 		return -ENOMEM;
492 
493 	ab->next = NULL;
494 	memset(&ab->descriptor, 0, sizeof(ab->descriptor));
495 	ab->descriptor.control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
496 						    DESCRIPTOR_STATUS |
497 						    DESCRIPTOR_BRANCH_ALWAYS);
498 	offset = offsetof(struct ar_buffer, data);
499 	ab->descriptor.req_count      = cpu_to_le16(PAGE_SIZE - offset);
500 	ab->descriptor.data_address   = cpu_to_le32(ab_bus + offset);
501 	ab->descriptor.res_count      = cpu_to_le16(PAGE_SIZE - offset);
502 	ab->descriptor.branch_address = 0;
503 
504 	ctx->last_buffer->descriptor.branch_address = cpu_to_le32(ab_bus | 1);
505 	ctx->last_buffer->next = ab;
506 	ctx->last_buffer = ab;
507 
508 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
509 	flush_writes(ctx->ohci);
510 
511 	return 0;
512 }
513 
514 static void ar_context_release(struct ar_context *ctx)
515 {
516 	struct ar_buffer *ab, *ab_next;
517 	size_t offset;
518 	dma_addr_t ab_bus;
519 
520 	for (ab = ctx->current_buffer; ab; ab = ab_next) {
521 		ab_next = ab->next;
522 		offset = offsetof(struct ar_buffer, data);
523 		ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
524 		dma_free_coherent(ctx->ohci->card.device, PAGE_SIZE,
525 				  ab, ab_bus);
526 	}
527 }
528 
529 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
530 #define cond_le32_to_cpu(v) \
531 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
532 #else
533 #define cond_le32_to_cpu(v) le32_to_cpu(v)
534 #endif
535 
536 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
537 {
538 	struct fw_ohci *ohci = ctx->ohci;
539 	struct fw_packet p;
540 	u32 status, length, tcode;
541 	int evt;
542 
543 	p.header[0] = cond_le32_to_cpu(buffer[0]);
544 	p.header[1] = cond_le32_to_cpu(buffer[1]);
545 	p.header[2] = cond_le32_to_cpu(buffer[2]);
546 
547 	tcode = (p.header[0] >> 4) & 0x0f;
548 	switch (tcode) {
549 	case TCODE_WRITE_QUADLET_REQUEST:
550 	case TCODE_READ_QUADLET_RESPONSE:
551 		p.header[3] = (__force __u32) buffer[3];
552 		p.header_length = 16;
553 		p.payload_length = 0;
554 		break;
555 
556 	case TCODE_READ_BLOCK_REQUEST :
557 		p.header[3] = cond_le32_to_cpu(buffer[3]);
558 		p.header_length = 16;
559 		p.payload_length = 0;
560 		break;
561 
562 	case TCODE_WRITE_BLOCK_REQUEST:
563 	case TCODE_READ_BLOCK_RESPONSE:
564 	case TCODE_LOCK_REQUEST:
565 	case TCODE_LOCK_RESPONSE:
566 		p.header[3] = cond_le32_to_cpu(buffer[3]);
567 		p.header_length = 16;
568 		p.payload_length = p.header[3] >> 16;
569 		break;
570 
571 	case TCODE_WRITE_RESPONSE:
572 	case TCODE_READ_QUADLET_REQUEST:
573 	case OHCI_TCODE_PHY_PACKET:
574 		p.header_length = 12;
575 		p.payload_length = 0;
576 		break;
577 
578 	default:
579 		/* FIXME: Stop context, discard everything, and restart? */
580 		p.header_length = 0;
581 		p.payload_length = 0;
582 	}
583 
584 	p.payload = (void *) buffer + p.header_length;
585 
586 	/* FIXME: What to do about evt_* errors? */
587 	length = (p.header_length + p.payload_length + 3) / 4;
588 	status = cond_le32_to_cpu(buffer[length]);
589 	evt    = (status >> 16) & 0x1f;
590 
591 	p.ack        = evt - 16;
592 	p.speed      = (status >> 21) & 0x7;
593 	p.timestamp  = status & 0xffff;
594 	p.generation = ohci->request_generation;
595 
596 	log_ar_at_event('R', p.speed, p.header, evt);
597 
598 	/*
599 	 * The OHCI bus reset handler synthesizes a phy packet with
600 	 * the new generation number when a bus reset happens (see
601 	 * section 8.4.2.3).  This helps us determine when a request
602 	 * was received and make sure we send the response in the same
603 	 * generation.  We only need this for requests; for responses
604 	 * we use the unique tlabel for finding the matching
605 	 * request.
606 	 *
607 	 * Alas some chips sometimes emit bus reset packets with a
608 	 * wrong generation.  We set the correct generation for these
609 	 * at a slightly incorrect time (in bus_reset_tasklet).
610 	 */
611 	if (evt == OHCI1394_evt_bus_reset) {
612 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
613 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
614 	} else if (ctx == &ohci->ar_request_ctx) {
615 		fw_core_handle_request(&ohci->card, &p);
616 	} else {
617 		fw_core_handle_response(&ohci->card, &p);
618 	}
619 
620 	return buffer + length + 1;
621 }
622 
623 static void ar_context_tasklet(unsigned long data)
624 {
625 	struct ar_context *ctx = (struct ar_context *)data;
626 	struct fw_ohci *ohci = ctx->ohci;
627 	struct ar_buffer *ab;
628 	struct descriptor *d;
629 	void *buffer, *end;
630 
631 	ab = ctx->current_buffer;
632 	d = &ab->descriptor;
633 
634 	if (d->res_count == 0) {
635 		size_t size, rest, offset;
636 		dma_addr_t start_bus;
637 		void *start;
638 
639 		/*
640 		 * This descriptor is finished and we may have a
641 		 * packet split across this and the next buffer. We
642 		 * reuse the page for reassembling the split packet.
643 		 */
644 
645 		offset = offsetof(struct ar_buffer, data);
646 		start = buffer = ab;
647 		start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
648 
649 		ab = ab->next;
650 		d = &ab->descriptor;
651 		size = buffer + PAGE_SIZE - ctx->pointer;
652 		rest = le16_to_cpu(d->req_count) - le16_to_cpu(d->res_count);
653 		memmove(buffer, ctx->pointer, size);
654 		memcpy(buffer + size, ab->data, rest);
655 		ctx->current_buffer = ab;
656 		ctx->pointer = (void *) ab->data + rest;
657 		end = buffer + size + rest;
658 
659 		while (buffer < end)
660 			buffer = handle_ar_packet(ctx, buffer);
661 
662 		dma_free_coherent(ohci->card.device, PAGE_SIZE,
663 				  start, start_bus);
664 		ar_context_add_page(ctx);
665 	} else {
666 		buffer = ctx->pointer;
667 		ctx->pointer = end =
668 			(void *) ab + PAGE_SIZE - le16_to_cpu(d->res_count);
669 
670 		while (buffer < end)
671 			buffer = handle_ar_packet(ctx, buffer);
672 	}
673 }
674 
675 static int ar_context_init(struct ar_context *ctx,
676 			   struct fw_ohci *ohci, u32 regs)
677 {
678 	struct ar_buffer ab;
679 
680 	ctx->regs        = regs;
681 	ctx->ohci        = ohci;
682 	ctx->last_buffer = &ab;
683 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
684 
685 	ar_context_add_page(ctx);
686 	ar_context_add_page(ctx);
687 	ctx->current_buffer = ab.next;
688 	ctx->pointer = ctx->current_buffer->data;
689 
690 	return 0;
691 }
692 
693 static void ar_context_run(struct ar_context *ctx)
694 {
695 	struct ar_buffer *ab = ctx->current_buffer;
696 	dma_addr_t ab_bus;
697 	size_t offset;
698 
699 	offset = offsetof(struct ar_buffer, data);
700 	ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
701 
702 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ab_bus | 1);
703 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
704 	flush_writes(ctx->ohci);
705 }
706 
707 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
708 {
709 	int b, key;
710 
711 	b   = (le16_to_cpu(d->control) & DESCRIPTOR_BRANCH_ALWAYS) >> 2;
712 	key = (le16_to_cpu(d->control) & DESCRIPTOR_KEY_IMMEDIATE) >> 8;
713 
714 	/* figure out which descriptor the branch address goes in */
715 	if (z == 2 && (b == 3 || key == 2))
716 		return d;
717 	else
718 		return d + z - 1;
719 }
720 
721 static void context_tasklet(unsigned long data)
722 {
723 	struct context *ctx = (struct context *) data;
724 	struct descriptor *d, *last;
725 	u32 address;
726 	int z;
727 	struct descriptor_buffer *desc;
728 
729 	desc = list_entry(ctx->buffer_list.next,
730 			struct descriptor_buffer, list);
731 	last = ctx->last;
732 	while (last->branch_address != 0) {
733 		struct descriptor_buffer *old_desc = desc;
734 		address = le32_to_cpu(last->branch_address);
735 		z = address & 0xf;
736 		address &= ~0xf;
737 
738 		/* If the branch address points to a buffer outside of the
739 		 * current buffer, advance to the next buffer. */
740 		if (address < desc->buffer_bus ||
741 				address >= desc->buffer_bus + desc->used)
742 			desc = list_entry(desc->list.next,
743 					struct descriptor_buffer, list);
744 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
745 		last = find_branch_descriptor(d, z);
746 
747 		if (!ctx->callback(ctx, d, last))
748 			break;
749 
750 		if (old_desc != desc) {
751 			/* If we've advanced to the next buffer, move the
752 			 * previous buffer to the free list. */
753 			unsigned long flags;
754 			old_desc->used = 0;
755 			spin_lock_irqsave(&ctx->ohci->lock, flags);
756 			list_move_tail(&old_desc->list, &ctx->buffer_list);
757 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
758 		}
759 		ctx->last = last;
760 	}
761 }
762 
763 /*
764  * Allocate a new buffer and add it to the list of free buffers for this
765  * context.  Must be called with ohci->lock held.
766  */
767 static int context_add_buffer(struct context *ctx)
768 {
769 	struct descriptor_buffer *desc;
770 	dma_addr_t uninitialized_var(bus_addr);
771 	int offset;
772 
773 	/*
774 	 * 16MB of descriptors should be far more than enough for any DMA
775 	 * program.  This will catch run-away userspace or DoS attacks.
776 	 */
777 	if (ctx->total_allocation >= 16*1024*1024)
778 		return -ENOMEM;
779 
780 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
781 			&bus_addr, GFP_ATOMIC);
782 	if (!desc)
783 		return -ENOMEM;
784 
785 	offset = (void *)&desc->buffer - (void *)desc;
786 	desc->buffer_size = PAGE_SIZE - offset;
787 	desc->buffer_bus = bus_addr + offset;
788 	desc->used = 0;
789 
790 	list_add_tail(&desc->list, &ctx->buffer_list);
791 	ctx->total_allocation += PAGE_SIZE;
792 
793 	return 0;
794 }
795 
796 static int context_init(struct context *ctx, struct fw_ohci *ohci,
797 			u32 regs, descriptor_callback_t callback)
798 {
799 	ctx->ohci = ohci;
800 	ctx->regs = regs;
801 	ctx->total_allocation = 0;
802 
803 	INIT_LIST_HEAD(&ctx->buffer_list);
804 	if (context_add_buffer(ctx) < 0)
805 		return -ENOMEM;
806 
807 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
808 			struct descriptor_buffer, list);
809 
810 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
811 	ctx->callback = callback;
812 
813 	/*
814 	 * We put a dummy descriptor in the buffer that has a NULL
815 	 * branch address and looks like it's been sent.  That way we
816 	 * have a descriptor to append DMA programs to.
817 	 */
818 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
819 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
820 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
821 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
822 	ctx->last = ctx->buffer_tail->buffer;
823 	ctx->prev = ctx->buffer_tail->buffer;
824 
825 	return 0;
826 }
827 
828 static void context_release(struct context *ctx)
829 {
830 	struct fw_card *card = &ctx->ohci->card;
831 	struct descriptor_buffer *desc, *tmp;
832 
833 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
834 		dma_free_coherent(card->device, PAGE_SIZE, desc,
835 			desc->buffer_bus -
836 			((void *)&desc->buffer - (void *)desc));
837 }
838 
839 /* Must be called with ohci->lock held */
840 static struct descriptor *context_get_descriptors(struct context *ctx,
841 						  int z, dma_addr_t *d_bus)
842 {
843 	struct descriptor *d = NULL;
844 	struct descriptor_buffer *desc = ctx->buffer_tail;
845 
846 	if (z * sizeof(*d) > desc->buffer_size)
847 		return NULL;
848 
849 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
850 		/* No room for the descriptor in this buffer, so advance to the
851 		 * next one. */
852 
853 		if (desc->list.next == &ctx->buffer_list) {
854 			/* If there is no free buffer next in the list,
855 			 * allocate one. */
856 			if (context_add_buffer(ctx) < 0)
857 				return NULL;
858 		}
859 		desc = list_entry(desc->list.next,
860 				struct descriptor_buffer, list);
861 		ctx->buffer_tail = desc;
862 	}
863 
864 	d = desc->buffer + desc->used / sizeof(*d);
865 	memset(d, 0, z * sizeof(*d));
866 	*d_bus = desc->buffer_bus + desc->used;
867 
868 	return d;
869 }
870 
871 static void context_run(struct context *ctx, u32 extra)
872 {
873 	struct fw_ohci *ohci = ctx->ohci;
874 
875 	reg_write(ohci, COMMAND_PTR(ctx->regs),
876 		  le32_to_cpu(ctx->last->branch_address));
877 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
878 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
879 	flush_writes(ohci);
880 }
881 
882 static void context_append(struct context *ctx,
883 			   struct descriptor *d, int z, int extra)
884 {
885 	dma_addr_t d_bus;
886 	struct descriptor_buffer *desc = ctx->buffer_tail;
887 
888 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
889 
890 	desc->used += (z + extra) * sizeof(*d);
891 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
892 	ctx->prev = find_branch_descriptor(d, z);
893 
894 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
895 	flush_writes(ctx->ohci);
896 }
897 
898 static void context_stop(struct context *ctx)
899 {
900 	u32 reg;
901 	int i;
902 
903 	reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
904 	flush_writes(ctx->ohci);
905 
906 	for (i = 0; i < 10; i++) {
907 		reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
908 		if ((reg & CONTEXT_ACTIVE) == 0)
909 			return;
910 
911 		mdelay(1);
912 	}
913 	fw_error("Error: DMA context still active (0x%08x)\n", reg);
914 }
915 
916 struct driver_data {
917 	struct fw_packet *packet;
918 };
919 
920 /*
921  * This function apppends a packet to the DMA queue for transmission.
922  * Must always be called with the ochi->lock held to ensure proper
923  * generation handling and locking around packet queue manipulation.
924  */
925 static int at_context_queue_packet(struct context *ctx,
926 				   struct fw_packet *packet)
927 {
928 	struct fw_ohci *ohci = ctx->ohci;
929 	dma_addr_t d_bus, uninitialized_var(payload_bus);
930 	struct driver_data *driver_data;
931 	struct descriptor *d, *last;
932 	__le32 *header;
933 	int z, tcode;
934 	u32 reg;
935 
936 	d = context_get_descriptors(ctx, 4, &d_bus);
937 	if (d == NULL) {
938 		packet->ack = RCODE_SEND_ERROR;
939 		return -1;
940 	}
941 
942 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
943 	d[0].res_count = cpu_to_le16(packet->timestamp);
944 
945 	/*
946 	 * The DMA format for asyncronous link packets is different
947 	 * from the IEEE1394 layout, so shift the fields around
948 	 * accordingly.  If header_length is 8, it's a PHY packet, to
949 	 * which we need to prepend an extra quadlet.
950 	 */
951 
952 	header = (__le32 *) &d[1];
953 	switch (packet->header_length) {
954 	case 16:
955 	case 12:
956 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
957 					(packet->speed << 16));
958 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
959 					(packet->header[0] & 0xffff0000));
960 		header[2] = cpu_to_le32(packet->header[2]);
961 
962 		tcode = (packet->header[0] >> 4) & 0x0f;
963 		if (TCODE_IS_BLOCK_PACKET(tcode))
964 			header[3] = cpu_to_le32(packet->header[3]);
965 		else
966 			header[3] = (__force __le32) packet->header[3];
967 
968 		d[0].req_count = cpu_to_le16(packet->header_length);
969 		break;
970 
971 	case 8:
972 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
973 					(packet->speed << 16));
974 		header[1] = cpu_to_le32(packet->header[0]);
975 		header[2] = cpu_to_le32(packet->header[1]);
976 		d[0].req_count = cpu_to_le16(12);
977 		break;
978 
979 	case 4:
980 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
981 					(packet->speed << 16));
982 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
983 		d[0].req_count = cpu_to_le16(8);
984 		break;
985 
986 	default:
987 		/* BUG(); */
988 		packet->ack = RCODE_SEND_ERROR;
989 		return -1;
990 	}
991 
992 	driver_data = (struct driver_data *) &d[3];
993 	driver_data->packet = packet;
994 	packet->driver_data = driver_data;
995 
996 	if (packet->payload_length > 0) {
997 		payload_bus =
998 			dma_map_single(ohci->card.device, packet->payload,
999 				       packet->payload_length, DMA_TO_DEVICE);
1000 		if (dma_mapping_error(ohci->card.device, payload_bus)) {
1001 			packet->ack = RCODE_SEND_ERROR;
1002 			return -1;
1003 		}
1004 		packet->payload_bus	= payload_bus;
1005 		packet->payload_mapped	= true;
1006 
1007 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1008 		d[2].data_address = cpu_to_le32(payload_bus);
1009 		last = &d[2];
1010 		z = 3;
1011 	} else {
1012 		last = &d[0];
1013 		z = 2;
1014 	}
1015 
1016 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1017 				     DESCRIPTOR_IRQ_ALWAYS |
1018 				     DESCRIPTOR_BRANCH_ALWAYS);
1019 
1020 	/*
1021 	 * If the controller and packet generations don't match, we need to
1022 	 * bail out and try again.  If IntEvent.busReset is set, the AT context
1023 	 * is halted, so appending to the context and trying to run it is
1024 	 * futile.  Most controllers do the right thing and just flush the AT
1025 	 * queue (per section 7.2.3.2 of the OHCI 1.1 specification), but
1026 	 * some controllers (like a JMicron JMB381 PCI-e) misbehave and wind
1027 	 * up stalling out.  So we just bail out in software and try again
1028 	 * later, and everyone is happy.
1029 	 * FIXME: Document how the locking works.
1030 	 */
1031 	if (ohci->generation != packet->generation ||
1032 	    reg_read(ohci, OHCI1394_IntEventSet) & OHCI1394_busReset) {
1033 		if (packet->payload_mapped)
1034 			dma_unmap_single(ohci->card.device, payload_bus,
1035 					 packet->payload_length, DMA_TO_DEVICE);
1036 		packet->ack = RCODE_GENERATION;
1037 		return -1;
1038 	}
1039 
1040 	context_append(ctx, d, z, 4 - z);
1041 
1042 	/* If the context isn't already running, start it up. */
1043 	reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1044 	if ((reg & CONTEXT_RUN) == 0)
1045 		context_run(ctx, 0);
1046 
1047 	return 0;
1048 }
1049 
1050 static int handle_at_packet(struct context *context,
1051 			    struct descriptor *d,
1052 			    struct descriptor *last)
1053 {
1054 	struct driver_data *driver_data;
1055 	struct fw_packet *packet;
1056 	struct fw_ohci *ohci = context->ohci;
1057 	int evt;
1058 
1059 	if (last->transfer_status == 0)
1060 		/* This descriptor isn't done yet, stop iteration. */
1061 		return 0;
1062 
1063 	driver_data = (struct driver_data *) &d[3];
1064 	packet = driver_data->packet;
1065 	if (packet == NULL)
1066 		/* This packet was cancelled, just continue. */
1067 		return 1;
1068 
1069 	if (packet->payload_mapped)
1070 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1071 				 packet->payload_length, DMA_TO_DEVICE);
1072 
1073 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1074 	packet->timestamp = le16_to_cpu(last->res_count);
1075 
1076 	log_ar_at_event('T', packet->speed, packet->header, evt);
1077 
1078 	switch (evt) {
1079 	case OHCI1394_evt_timeout:
1080 		/* Async response transmit timed out. */
1081 		packet->ack = RCODE_CANCELLED;
1082 		break;
1083 
1084 	case OHCI1394_evt_flushed:
1085 		/*
1086 		 * The packet was flushed should give same error as
1087 		 * when we try to use a stale generation count.
1088 		 */
1089 		packet->ack = RCODE_GENERATION;
1090 		break;
1091 
1092 	case OHCI1394_evt_missing_ack:
1093 		/*
1094 		 * Using a valid (current) generation count, but the
1095 		 * node is not on the bus or not sending acks.
1096 		 */
1097 		packet->ack = RCODE_NO_ACK;
1098 		break;
1099 
1100 	case ACK_COMPLETE + 0x10:
1101 	case ACK_PENDING + 0x10:
1102 	case ACK_BUSY_X + 0x10:
1103 	case ACK_BUSY_A + 0x10:
1104 	case ACK_BUSY_B + 0x10:
1105 	case ACK_DATA_ERROR + 0x10:
1106 	case ACK_TYPE_ERROR + 0x10:
1107 		packet->ack = evt - 0x10;
1108 		break;
1109 
1110 	default:
1111 		packet->ack = RCODE_SEND_ERROR;
1112 		break;
1113 	}
1114 
1115 	packet->callback(packet, &ohci->card, packet->ack);
1116 
1117 	return 1;
1118 }
1119 
1120 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1121 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1122 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1123 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1124 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1125 
1126 static void handle_local_rom(struct fw_ohci *ohci,
1127 			     struct fw_packet *packet, u32 csr)
1128 {
1129 	struct fw_packet response;
1130 	int tcode, length, i;
1131 
1132 	tcode = HEADER_GET_TCODE(packet->header[0]);
1133 	if (TCODE_IS_BLOCK_PACKET(tcode))
1134 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1135 	else
1136 		length = 4;
1137 
1138 	i = csr - CSR_CONFIG_ROM;
1139 	if (i + length > CONFIG_ROM_SIZE) {
1140 		fw_fill_response(&response, packet->header,
1141 				 RCODE_ADDRESS_ERROR, NULL, 0);
1142 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1143 		fw_fill_response(&response, packet->header,
1144 				 RCODE_TYPE_ERROR, NULL, 0);
1145 	} else {
1146 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1147 				 (void *) ohci->config_rom + i, length);
1148 	}
1149 
1150 	fw_core_handle_response(&ohci->card, &response);
1151 }
1152 
1153 static void handle_local_lock(struct fw_ohci *ohci,
1154 			      struct fw_packet *packet, u32 csr)
1155 {
1156 	struct fw_packet response;
1157 	int tcode, length, ext_tcode, sel;
1158 	__be32 *payload, lock_old;
1159 	u32 lock_arg, lock_data;
1160 
1161 	tcode = HEADER_GET_TCODE(packet->header[0]);
1162 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1163 	payload = packet->payload;
1164 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1165 
1166 	if (tcode == TCODE_LOCK_REQUEST &&
1167 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1168 		lock_arg = be32_to_cpu(payload[0]);
1169 		lock_data = be32_to_cpu(payload[1]);
1170 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1171 		lock_arg = 0;
1172 		lock_data = 0;
1173 	} else {
1174 		fw_fill_response(&response, packet->header,
1175 				 RCODE_TYPE_ERROR, NULL, 0);
1176 		goto out;
1177 	}
1178 
1179 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1180 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1181 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1182 	reg_write(ohci, OHCI1394_CSRControl, sel);
1183 
1184 	if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000)
1185 		lock_old = cpu_to_be32(reg_read(ohci, OHCI1394_CSRData));
1186 	else
1187 		fw_notify("swap not done yet\n");
1188 
1189 	fw_fill_response(&response, packet->header,
1190 			 RCODE_COMPLETE, &lock_old, sizeof(lock_old));
1191  out:
1192 	fw_core_handle_response(&ohci->card, &response);
1193 }
1194 
1195 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1196 {
1197 	u64 offset;
1198 	u32 csr;
1199 
1200 	if (ctx == &ctx->ohci->at_request_ctx) {
1201 		packet->ack = ACK_PENDING;
1202 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1203 	}
1204 
1205 	offset =
1206 		((unsigned long long)
1207 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1208 		packet->header[2];
1209 	csr = offset - CSR_REGISTER_BASE;
1210 
1211 	/* Handle config rom reads. */
1212 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1213 		handle_local_rom(ctx->ohci, packet, csr);
1214 	else switch (csr) {
1215 	case CSR_BUS_MANAGER_ID:
1216 	case CSR_BANDWIDTH_AVAILABLE:
1217 	case CSR_CHANNELS_AVAILABLE_HI:
1218 	case CSR_CHANNELS_AVAILABLE_LO:
1219 		handle_local_lock(ctx->ohci, packet, csr);
1220 		break;
1221 	default:
1222 		if (ctx == &ctx->ohci->at_request_ctx)
1223 			fw_core_handle_request(&ctx->ohci->card, packet);
1224 		else
1225 			fw_core_handle_response(&ctx->ohci->card, packet);
1226 		break;
1227 	}
1228 
1229 	if (ctx == &ctx->ohci->at_response_ctx) {
1230 		packet->ack = ACK_COMPLETE;
1231 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1232 	}
1233 }
1234 
1235 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1236 {
1237 	unsigned long flags;
1238 	int ret;
1239 
1240 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1241 
1242 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1243 	    ctx->ohci->generation == packet->generation) {
1244 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1245 		handle_local_request(ctx, packet);
1246 		return;
1247 	}
1248 
1249 	ret = at_context_queue_packet(ctx, packet);
1250 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1251 
1252 	if (ret < 0)
1253 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1254 
1255 }
1256 
1257 static void bus_reset_tasklet(unsigned long data)
1258 {
1259 	struct fw_ohci *ohci = (struct fw_ohci *)data;
1260 	int self_id_count, i, j, reg;
1261 	int generation, new_generation;
1262 	unsigned long flags;
1263 	void *free_rom = NULL;
1264 	dma_addr_t free_rom_bus = 0;
1265 
1266 	reg = reg_read(ohci, OHCI1394_NodeID);
1267 	if (!(reg & OHCI1394_NodeID_idValid)) {
1268 		fw_notify("node ID not valid, new bus reset in progress\n");
1269 		return;
1270 	}
1271 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1272 		fw_notify("malconfigured bus\n");
1273 		return;
1274 	}
1275 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1276 			       OHCI1394_NodeID_nodeNumber);
1277 
1278 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1279 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1280 		fw_notify("inconsistent self IDs\n");
1281 		return;
1282 	}
1283 	/*
1284 	 * The count in the SelfIDCount register is the number of
1285 	 * bytes in the self ID receive buffer.  Since we also receive
1286 	 * the inverted quadlets and a header quadlet, we shift one
1287 	 * bit extra to get the actual number of self IDs.
1288 	 */
1289 	self_id_count = (reg >> 3) & 0xff;
1290 	if (self_id_count == 0 || self_id_count > 252) {
1291 		fw_notify("inconsistent self IDs\n");
1292 		return;
1293 	}
1294 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1295 	rmb();
1296 
1297 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1298 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1299 			fw_notify("inconsistent self IDs\n");
1300 			return;
1301 		}
1302 		ohci->self_id_buffer[j] =
1303 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1304 	}
1305 	rmb();
1306 
1307 	/*
1308 	 * Check the consistency of the self IDs we just read.  The
1309 	 * problem we face is that a new bus reset can start while we
1310 	 * read out the self IDs from the DMA buffer. If this happens,
1311 	 * the DMA buffer will be overwritten with new self IDs and we
1312 	 * will read out inconsistent data.  The OHCI specification
1313 	 * (section 11.2) recommends a technique similar to
1314 	 * linux/seqlock.h, where we remember the generation of the
1315 	 * self IDs in the buffer before reading them out and compare
1316 	 * it to the current generation after reading them out.  If
1317 	 * the two generations match we know we have a consistent set
1318 	 * of self IDs.
1319 	 */
1320 
1321 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1322 	if (new_generation != generation) {
1323 		fw_notify("recursive bus reset detected, "
1324 			  "discarding self ids\n");
1325 		return;
1326 	}
1327 
1328 	/* FIXME: Document how the locking works. */
1329 	spin_lock_irqsave(&ohci->lock, flags);
1330 
1331 	ohci->generation = generation;
1332 	context_stop(&ohci->at_request_ctx);
1333 	context_stop(&ohci->at_response_ctx);
1334 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1335 
1336 	if (ohci->quirks & QUIRK_RESET_PACKET)
1337 		ohci->request_generation = generation;
1338 
1339 	/*
1340 	 * This next bit is unrelated to the AT context stuff but we
1341 	 * have to do it under the spinlock also.  If a new config rom
1342 	 * was set up before this reset, the old one is now no longer
1343 	 * in use and we can free it. Update the config rom pointers
1344 	 * to point to the current config rom and clear the
1345 	 * next_config_rom pointer so a new udpate can take place.
1346 	 */
1347 
1348 	if (ohci->next_config_rom != NULL) {
1349 		if (ohci->next_config_rom != ohci->config_rom) {
1350 			free_rom      = ohci->config_rom;
1351 			free_rom_bus  = ohci->config_rom_bus;
1352 		}
1353 		ohci->config_rom      = ohci->next_config_rom;
1354 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1355 		ohci->next_config_rom = NULL;
1356 
1357 		/*
1358 		 * Restore config_rom image and manually update
1359 		 * config_rom registers.  Writing the header quadlet
1360 		 * will indicate that the config rom is ready, so we
1361 		 * do that last.
1362 		 */
1363 		reg_write(ohci, OHCI1394_BusOptions,
1364 			  be32_to_cpu(ohci->config_rom[2]));
1365 		ohci->config_rom[0] = ohci->next_header;
1366 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1367 			  be32_to_cpu(ohci->next_header));
1368 	}
1369 
1370 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1371 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1372 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1373 #endif
1374 
1375 	spin_unlock_irqrestore(&ohci->lock, flags);
1376 
1377 	if (free_rom)
1378 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1379 				  free_rom, free_rom_bus);
1380 
1381 	log_selfids(ohci->node_id, generation,
1382 		    self_id_count, ohci->self_id_buffer);
1383 
1384 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1385 				 self_id_count, ohci->self_id_buffer);
1386 }
1387 
1388 static irqreturn_t irq_handler(int irq, void *data)
1389 {
1390 	struct fw_ohci *ohci = data;
1391 	u32 event, iso_event;
1392 	int i;
1393 
1394 	event = reg_read(ohci, OHCI1394_IntEventClear);
1395 
1396 	if (!event || !~event)
1397 		return IRQ_NONE;
1398 
1399 	/* busReset must not be cleared yet, see OHCI 1.1 clause 7.2.3.2 */
1400 	reg_write(ohci, OHCI1394_IntEventClear, event & ~OHCI1394_busReset);
1401 	log_irqs(event);
1402 
1403 	if (event & OHCI1394_selfIDComplete)
1404 		tasklet_schedule(&ohci->bus_reset_tasklet);
1405 
1406 	if (event & OHCI1394_RQPkt)
1407 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1408 
1409 	if (event & OHCI1394_RSPkt)
1410 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1411 
1412 	if (event & OHCI1394_reqTxComplete)
1413 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
1414 
1415 	if (event & OHCI1394_respTxComplete)
1416 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
1417 
1418 	iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1419 	reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1420 
1421 	while (iso_event) {
1422 		i = ffs(iso_event) - 1;
1423 		tasklet_schedule(&ohci->ir_context_list[i].context.tasklet);
1424 		iso_event &= ~(1 << i);
1425 	}
1426 
1427 	iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1428 	reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1429 
1430 	while (iso_event) {
1431 		i = ffs(iso_event) - 1;
1432 		tasklet_schedule(&ohci->it_context_list[i].context.tasklet);
1433 		iso_event &= ~(1 << i);
1434 	}
1435 
1436 	if (unlikely(event & OHCI1394_regAccessFail))
1437 		fw_error("Register access failure - "
1438 			 "please notify linux1394-devel@lists.sf.net\n");
1439 
1440 	if (unlikely(event & OHCI1394_postedWriteErr))
1441 		fw_error("PCI posted write error\n");
1442 
1443 	if (unlikely(event & OHCI1394_cycleTooLong)) {
1444 		if (printk_ratelimit())
1445 			fw_notify("isochronous cycle too long\n");
1446 		reg_write(ohci, OHCI1394_LinkControlSet,
1447 			  OHCI1394_LinkControl_cycleMaster);
1448 	}
1449 
1450 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
1451 		/*
1452 		 * We need to clear this event bit in order to make
1453 		 * cycleMatch isochronous I/O work.  In theory we should
1454 		 * stop active cycleMatch iso contexts now and restart
1455 		 * them at least two cycles later.  (FIXME?)
1456 		 */
1457 		if (printk_ratelimit())
1458 			fw_notify("isochronous cycle inconsistent\n");
1459 	}
1460 
1461 	return IRQ_HANDLED;
1462 }
1463 
1464 static int software_reset(struct fw_ohci *ohci)
1465 {
1466 	int i;
1467 
1468 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1469 
1470 	for (i = 0; i < OHCI_LOOP_COUNT; i++) {
1471 		if ((reg_read(ohci, OHCI1394_HCControlSet) &
1472 		     OHCI1394_HCControl_softReset) == 0)
1473 			return 0;
1474 		msleep(1);
1475 	}
1476 
1477 	return -EBUSY;
1478 }
1479 
1480 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
1481 {
1482 	size_t size = length * 4;
1483 
1484 	memcpy(dest, src, size);
1485 	if (size < CONFIG_ROM_SIZE)
1486 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
1487 }
1488 
1489 static int ohci_enable(struct fw_card *card,
1490 		       const __be32 *config_rom, size_t length)
1491 {
1492 	struct fw_ohci *ohci = fw_ohci(card);
1493 	struct pci_dev *dev = to_pci_dev(card->device);
1494 	u32 lps;
1495 	int i;
1496 
1497 	if (software_reset(ohci)) {
1498 		fw_error("Failed to reset ohci card.\n");
1499 		return -EBUSY;
1500 	}
1501 
1502 	/*
1503 	 * Now enable LPS, which we need in order to start accessing
1504 	 * most of the registers.  In fact, on some cards (ALI M5251),
1505 	 * accessing registers in the SClk domain without LPS enabled
1506 	 * will lock up the machine.  Wait 50msec to make sure we have
1507 	 * full link enabled.  However, with some cards (well, at least
1508 	 * a JMicron PCIe card), we have to try again sometimes.
1509 	 */
1510 	reg_write(ohci, OHCI1394_HCControlSet,
1511 		  OHCI1394_HCControl_LPS |
1512 		  OHCI1394_HCControl_postedWriteEnable);
1513 	flush_writes(ohci);
1514 
1515 	for (lps = 0, i = 0; !lps && i < 3; i++) {
1516 		msleep(50);
1517 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
1518 		      OHCI1394_HCControl_LPS;
1519 	}
1520 
1521 	if (!lps) {
1522 		fw_error("Failed to set Link Power Status\n");
1523 		return -EIO;
1524 	}
1525 
1526 	reg_write(ohci, OHCI1394_HCControlClear,
1527 		  OHCI1394_HCControl_noByteSwapData);
1528 
1529 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
1530 	reg_write(ohci, OHCI1394_LinkControlClear,
1531 		  OHCI1394_LinkControl_rcvPhyPkt);
1532 	reg_write(ohci, OHCI1394_LinkControlSet,
1533 		  OHCI1394_LinkControl_rcvSelfID |
1534 		  OHCI1394_LinkControl_cycleTimerEnable |
1535 		  OHCI1394_LinkControl_cycleMaster);
1536 
1537 	reg_write(ohci, OHCI1394_ATRetries,
1538 		  OHCI1394_MAX_AT_REQ_RETRIES |
1539 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
1540 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8));
1541 
1542 	ar_context_run(&ohci->ar_request_ctx);
1543 	ar_context_run(&ohci->ar_response_ctx);
1544 
1545 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
1546 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
1547 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
1548 	reg_write(ohci, OHCI1394_IntMaskSet,
1549 		  OHCI1394_selfIDComplete |
1550 		  OHCI1394_RQPkt | OHCI1394_RSPkt |
1551 		  OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
1552 		  OHCI1394_isochRx | OHCI1394_isochTx |
1553 		  OHCI1394_postedWriteErr | OHCI1394_cycleTooLong |
1554 		  OHCI1394_cycleInconsistent | OHCI1394_regAccessFail |
1555 		  OHCI1394_masterIntEnable);
1556 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
1557 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_busReset);
1558 
1559 	/* Activate link_on bit and contender bit in our self ID packets.*/
1560 	if (ohci_update_phy_reg(card, 4, 0,
1561 				PHY_LINK_ACTIVE | PHY_CONTENDER) < 0)
1562 		return -EIO;
1563 
1564 	/*
1565 	 * When the link is not yet enabled, the atomic config rom
1566 	 * update mechanism described below in ohci_set_config_rom()
1567 	 * is not active.  We have to update ConfigRomHeader and
1568 	 * BusOptions manually, and the write to ConfigROMmap takes
1569 	 * effect immediately.  We tie this to the enabling of the
1570 	 * link, so we have a valid config rom before enabling - the
1571 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
1572 	 * values before enabling.
1573 	 *
1574 	 * However, when the ConfigROMmap is written, some controllers
1575 	 * always read back quadlets 0 and 2 from the config rom to
1576 	 * the ConfigRomHeader and BusOptions registers on bus reset.
1577 	 * They shouldn't do that in this initial case where the link
1578 	 * isn't enabled.  This means we have to use the same
1579 	 * workaround here, setting the bus header to 0 and then write
1580 	 * the right values in the bus reset tasklet.
1581 	 */
1582 
1583 	if (config_rom) {
1584 		ohci->next_config_rom =
1585 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1586 					   &ohci->next_config_rom_bus,
1587 					   GFP_KERNEL);
1588 		if (ohci->next_config_rom == NULL)
1589 			return -ENOMEM;
1590 
1591 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1592 	} else {
1593 		/*
1594 		 * In the suspend case, config_rom is NULL, which
1595 		 * means that we just reuse the old config rom.
1596 		 */
1597 		ohci->next_config_rom = ohci->config_rom;
1598 		ohci->next_config_rom_bus = ohci->config_rom_bus;
1599 	}
1600 
1601 	ohci->next_header = ohci->next_config_rom[0];
1602 	ohci->next_config_rom[0] = 0;
1603 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
1604 	reg_write(ohci, OHCI1394_BusOptions,
1605 		  be32_to_cpu(ohci->next_config_rom[2]));
1606 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
1607 
1608 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
1609 
1610 	if (request_irq(dev->irq, irq_handler,
1611 			IRQF_SHARED, ohci_driver_name, ohci)) {
1612 		fw_error("Failed to allocate shared interrupt %d.\n",
1613 			 dev->irq);
1614 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1615 				  ohci->config_rom, ohci->config_rom_bus);
1616 		return -EIO;
1617 	}
1618 
1619 	reg_write(ohci, OHCI1394_HCControlSet,
1620 		  OHCI1394_HCControl_linkEnable |
1621 		  OHCI1394_HCControl_BIBimageValid);
1622 	flush_writes(ohci);
1623 
1624 	/*
1625 	 * We are ready to go, initiate bus reset to finish the
1626 	 * initialization.
1627 	 */
1628 
1629 	fw_core_initiate_bus_reset(&ohci->card, 1);
1630 
1631 	return 0;
1632 }
1633 
1634 static int ohci_set_config_rom(struct fw_card *card,
1635 			       const __be32 *config_rom, size_t length)
1636 {
1637 	struct fw_ohci *ohci;
1638 	unsigned long flags;
1639 	int ret = -EBUSY;
1640 	__be32 *next_config_rom;
1641 	dma_addr_t uninitialized_var(next_config_rom_bus);
1642 
1643 	ohci = fw_ohci(card);
1644 
1645 	/*
1646 	 * When the OHCI controller is enabled, the config rom update
1647 	 * mechanism is a bit tricky, but easy enough to use.  See
1648 	 * section 5.5.6 in the OHCI specification.
1649 	 *
1650 	 * The OHCI controller caches the new config rom address in a
1651 	 * shadow register (ConfigROMmapNext) and needs a bus reset
1652 	 * for the changes to take place.  When the bus reset is
1653 	 * detected, the controller loads the new values for the
1654 	 * ConfigRomHeader and BusOptions registers from the specified
1655 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
1656 	 * shadow register. All automatically and atomically.
1657 	 *
1658 	 * Now, there's a twist to this story.  The automatic load of
1659 	 * ConfigRomHeader and BusOptions doesn't honor the
1660 	 * noByteSwapData bit, so with a be32 config rom, the
1661 	 * controller will load be32 values in to these registers
1662 	 * during the atomic update, even on litte endian
1663 	 * architectures.  The workaround we use is to put a 0 in the
1664 	 * header quadlet; 0 is endian agnostic and means that the
1665 	 * config rom isn't ready yet.  In the bus reset tasklet we
1666 	 * then set up the real values for the two registers.
1667 	 *
1668 	 * We use ohci->lock to avoid racing with the code that sets
1669 	 * ohci->next_config_rom to NULL (see bus_reset_tasklet).
1670 	 */
1671 
1672 	next_config_rom =
1673 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1674 				   &next_config_rom_bus, GFP_KERNEL);
1675 	if (next_config_rom == NULL)
1676 		return -ENOMEM;
1677 
1678 	spin_lock_irqsave(&ohci->lock, flags);
1679 
1680 	if (ohci->next_config_rom == NULL) {
1681 		ohci->next_config_rom = next_config_rom;
1682 		ohci->next_config_rom_bus = next_config_rom_bus;
1683 
1684 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1685 
1686 		ohci->next_header = config_rom[0];
1687 		ohci->next_config_rom[0] = 0;
1688 
1689 		reg_write(ohci, OHCI1394_ConfigROMmap,
1690 			  ohci->next_config_rom_bus);
1691 		ret = 0;
1692 	}
1693 
1694 	spin_unlock_irqrestore(&ohci->lock, flags);
1695 
1696 	/*
1697 	 * Now initiate a bus reset to have the changes take
1698 	 * effect. We clean up the old config rom memory and DMA
1699 	 * mappings in the bus reset tasklet, since the OHCI
1700 	 * controller could need to access it before the bus reset
1701 	 * takes effect.
1702 	 */
1703 	if (ret == 0)
1704 		fw_core_initiate_bus_reset(&ohci->card, 1);
1705 	else
1706 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1707 				  next_config_rom, next_config_rom_bus);
1708 
1709 	return ret;
1710 }
1711 
1712 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
1713 {
1714 	struct fw_ohci *ohci = fw_ohci(card);
1715 
1716 	at_context_transmit(&ohci->at_request_ctx, packet);
1717 }
1718 
1719 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
1720 {
1721 	struct fw_ohci *ohci = fw_ohci(card);
1722 
1723 	at_context_transmit(&ohci->at_response_ctx, packet);
1724 }
1725 
1726 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
1727 {
1728 	struct fw_ohci *ohci = fw_ohci(card);
1729 	struct context *ctx = &ohci->at_request_ctx;
1730 	struct driver_data *driver_data = packet->driver_data;
1731 	int ret = -ENOENT;
1732 
1733 	tasklet_disable(&ctx->tasklet);
1734 
1735 	if (packet->ack != 0)
1736 		goto out;
1737 
1738 	if (packet->payload_mapped)
1739 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1740 				 packet->payload_length, DMA_TO_DEVICE);
1741 
1742 	log_ar_at_event('T', packet->speed, packet->header, 0x20);
1743 	driver_data->packet = NULL;
1744 	packet->ack = RCODE_CANCELLED;
1745 	packet->callback(packet, &ohci->card, packet->ack);
1746 	ret = 0;
1747  out:
1748 	tasklet_enable(&ctx->tasklet);
1749 
1750 	return ret;
1751 }
1752 
1753 static int ohci_enable_phys_dma(struct fw_card *card,
1754 				int node_id, int generation)
1755 {
1756 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1757 	return 0;
1758 #else
1759 	struct fw_ohci *ohci = fw_ohci(card);
1760 	unsigned long flags;
1761 	int n, ret = 0;
1762 
1763 	/*
1764 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
1765 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
1766 	 */
1767 
1768 	spin_lock_irqsave(&ohci->lock, flags);
1769 
1770 	if (ohci->generation != generation) {
1771 		ret = -ESTALE;
1772 		goto out;
1773 	}
1774 
1775 	/*
1776 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
1777 	 * enabled for _all_ nodes on remote buses.
1778 	 */
1779 
1780 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
1781 	if (n < 32)
1782 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
1783 	else
1784 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
1785 
1786 	flush_writes(ohci);
1787  out:
1788 	spin_unlock_irqrestore(&ohci->lock, flags);
1789 
1790 	return ret;
1791 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
1792 }
1793 
1794 static u32 cycle_timer_ticks(u32 cycle_timer)
1795 {
1796 	u32 ticks;
1797 
1798 	ticks = cycle_timer & 0xfff;
1799 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1800 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1801 
1802 	return ticks;
1803 }
1804 
1805 /*
1806  * Some controllers exhibit one or more of the following bugs when updating the
1807  * iso cycle timer register:
1808  *  - When the lowest six bits are wrapping around to zero, a read that happens
1809  *    at the same time will return garbage in the lowest ten bits.
1810  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1811  *    not incremented for about 60 ns.
1812  *  - Occasionally, the entire register reads zero.
1813  *
1814  * To catch these, we read the register three times and ensure that the
1815  * difference between each two consecutive reads is approximately the same, i.e.
1816  * less than twice the other.  Furthermore, any negative difference indicates an
1817  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1818  * execute, so we have enough precision to compute the ratio of the differences.)
1819  */
1820 static u32 ohci_get_cycle_time(struct fw_card *card)
1821 {
1822 	struct fw_ohci *ohci = fw_ohci(card);
1823 	u32 c0, c1, c2;
1824 	u32 t0, t1, t2;
1825 	s32 diff01, diff12;
1826 	int i;
1827 
1828 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1829 
1830 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1831 		i = 0;
1832 		c1 = c2;
1833 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1834 		do {
1835 			c0 = c1;
1836 			c1 = c2;
1837 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1838 			t0 = cycle_timer_ticks(c0);
1839 			t1 = cycle_timer_ticks(c1);
1840 			t2 = cycle_timer_ticks(c2);
1841 			diff01 = t1 - t0;
1842 			diff12 = t2 - t1;
1843 		} while ((diff01 <= 0 || diff12 <= 0 ||
1844 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1845 			 && i++ < 20);
1846 	}
1847 
1848 	return c2;
1849 }
1850 
1851 static void copy_iso_headers(struct iso_context *ctx, void *p)
1852 {
1853 	int i = ctx->header_length;
1854 
1855 	if (i + ctx->base.header_size > PAGE_SIZE)
1856 		return;
1857 
1858 	/*
1859 	 * The iso header is byteswapped to little endian by
1860 	 * the controller, but the remaining header quadlets
1861 	 * are big endian.  We want to present all the headers
1862 	 * as big endian, so we have to swap the first quadlet.
1863 	 */
1864 	if (ctx->base.header_size > 0)
1865 		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
1866 	if (ctx->base.header_size > 4)
1867 		*(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
1868 	if (ctx->base.header_size > 8)
1869 		memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
1870 	ctx->header_length += ctx->base.header_size;
1871 }
1872 
1873 static int handle_ir_packet_per_buffer(struct context *context,
1874 				       struct descriptor *d,
1875 				       struct descriptor *last)
1876 {
1877 	struct iso_context *ctx =
1878 		container_of(context, struct iso_context, context);
1879 	struct descriptor *pd;
1880 	__le32 *ir_header;
1881 	void *p;
1882 
1883 	for (pd = d; pd <= last; pd++) {
1884 		if (pd->transfer_status)
1885 			break;
1886 	}
1887 	if (pd > last)
1888 		/* Descriptor(s) not done yet, stop iteration */
1889 		return 0;
1890 
1891 	p = last + 1;
1892 	copy_iso_headers(ctx, p);
1893 
1894 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
1895 		ir_header = (__le32 *) p;
1896 		ctx->base.callback(&ctx->base,
1897 				   le32_to_cpu(ir_header[0]) & 0xffff,
1898 				   ctx->header_length, ctx->header,
1899 				   ctx->base.callback_data);
1900 		ctx->header_length = 0;
1901 	}
1902 
1903 	return 1;
1904 }
1905 
1906 static int handle_it_packet(struct context *context,
1907 			    struct descriptor *d,
1908 			    struct descriptor *last)
1909 {
1910 	struct iso_context *ctx =
1911 		container_of(context, struct iso_context, context);
1912 	int i;
1913 	struct descriptor *pd;
1914 
1915 	for (pd = d; pd <= last; pd++)
1916 		if (pd->transfer_status)
1917 			break;
1918 	if (pd > last)
1919 		/* Descriptor(s) not done yet, stop iteration */
1920 		return 0;
1921 
1922 	i = ctx->header_length;
1923 	if (i + 4 < PAGE_SIZE) {
1924 		/* Present this value as big-endian to match the receive code */
1925 		*(__be32 *)(ctx->header + i) = cpu_to_be32(
1926 				((u32)le16_to_cpu(pd->transfer_status) << 16) |
1927 				le16_to_cpu(pd->res_count));
1928 		ctx->header_length += 4;
1929 	}
1930 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
1931 		ctx->base.callback(&ctx->base, le16_to_cpu(last->res_count),
1932 				   ctx->header_length, ctx->header,
1933 				   ctx->base.callback_data);
1934 		ctx->header_length = 0;
1935 	}
1936 	return 1;
1937 }
1938 
1939 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
1940 				int type, int channel, size_t header_size)
1941 {
1942 	struct fw_ohci *ohci = fw_ohci(card);
1943 	struct iso_context *ctx, *list;
1944 	descriptor_callback_t callback;
1945 	u64 *channels, dont_care = ~0ULL;
1946 	u32 *mask, regs;
1947 	unsigned long flags;
1948 	int index, ret = -ENOMEM;
1949 
1950 	if (type == FW_ISO_CONTEXT_TRANSMIT) {
1951 		channels = &dont_care;
1952 		mask = &ohci->it_context_mask;
1953 		list = ohci->it_context_list;
1954 		callback = handle_it_packet;
1955 	} else {
1956 		channels = &ohci->ir_context_channels;
1957 		mask = &ohci->ir_context_mask;
1958 		list = ohci->ir_context_list;
1959 		callback = handle_ir_packet_per_buffer;
1960 	}
1961 
1962 	spin_lock_irqsave(&ohci->lock, flags);
1963 	index = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
1964 	if (index >= 0) {
1965 		*channels &= ~(1ULL << channel);
1966 		*mask &= ~(1 << index);
1967 	}
1968 	spin_unlock_irqrestore(&ohci->lock, flags);
1969 
1970 	if (index < 0)
1971 		return ERR_PTR(-EBUSY);
1972 
1973 	if (type == FW_ISO_CONTEXT_TRANSMIT)
1974 		regs = OHCI1394_IsoXmitContextBase(index);
1975 	else
1976 		regs = OHCI1394_IsoRcvContextBase(index);
1977 
1978 	ctx = &list[index];
1979 	memset(ctx, 0, sizeof(*ctx));
1980 	ctx->header_length = 0;
1981 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
1982 	if (ctx->header == NULL)
1983 		goto out;
1984 
1985 	ret = context_init(&ctx->context, ohci, regs, callback);
1986 	if (ret < 0)
1987 		goto out_with_header;
1988 
1989 	return &ctx->base;
1990 
1991  out_with_header:
1992 	free_page((unsigned long)ctx->header);
1993  out:
1994 	spin_lock_irqsave(&ohci->lock, flags);
1995 	*mask |= 1 << index;
1996 	spin_unlock_irqrestore(&ohci->lock, flags);
1997 
1998 	return ERR_PTR(ret);
1999 }
2000 
2001 static int ohci_start_iso(struct fw_iso_context *base,
2002 			  s32 cycle, u32 sync, u32 tags)
2003 {
2004 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2005 	struct fw_ohci *ohci = ctx->context.ohci;
2006 	u32 control, match;
2007 	int index;
2008 
2009 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2010 		index = ctx - ohci->it_context_list;
2011 		match = 0;
2012 		if (cycle >= 0)
2013 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
2014 				(cycle & 0x7fff) << 16;
2015 
2016 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
2017 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
2018 		context_run(&ctx->context, match);
2019 	} else {
2020 		index = ctx - ohci->ir_context_list;
2021 		control = IR_CONTEXT_ISOCH_HEADER;
2022 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
2023 		if (cycle >= 0) {
2024 			match |= (cycle & 0x07fff) << 12;
2025 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
2026 		}
2027 
2028 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2029 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2030 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2031 		context_run(&ctx->context, control);
2032 	}
2033 
2034 	return 0;
2035 }
2036 
2037 static int ohci_stop_iso(struct fw_iso_context *base)
2038 {
2039 	struct fw_ohci *ohci = fw_ohci(base->card);
2040 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2041 	int index;
2042 
2043 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2044 		index = ctx - ohci->it_context_list;
2045 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2046 	} else {
2047 		index = ctx - ohci->ir_context_list;
2048 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2049 	}
2050 	flush_writes(ohci);
2051 	context_stop(&ctx->context);
2052 
2053 	return 0;
2054 }
2055 
2056 static void ohci_free_iso_context(struct fw_iso_context *base)
2057 {
2058 	struct fw_ohci *ohci = fw_ohci(base->card);
2059 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2060 	unsigned long flags;
2061 	int index;
2062 
2063 	ohci_stop_iso(base);
2064 	context_release(&ctx->context);
2065 	free_page((unsigned long)ctx->header);
2066 
2067 	spin_lock_irqsave(&ohci->lock, flags);
2068 
2069 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2070 		index = ctx - ohci->it_context_list;
2071 		ohci->it_context_mask |= 1 << index;
2072 	} else {
2073 		index = ctx - ohci->ir_context_list;
2074 		ohci->ir_context_mask |= 1 << index;
2075 		ohci->ir_context_channels |= 1ULL << base->channel;
2076 	}
2077 
2078 	spin_unlock_irqrestore(&ohci->lock, flags);
2079 }
2080 
2081 static int ohci_queue_iso_transmit(struct fw_iso_context *base,
2082 				   struct fw_iso_packet *packet,
2083 				   struct fw_iso_buffer *buffer,
2084 				   unsigned long payload)
2085 {
2086 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2087 	struct descriptor *d, *last, *pd;
2088 	struct fw_iso_packet *p;
2089 	__le32 *header;
2090 	dma_addr_t d_bus, page_bus;
2091 	u32 z, header_z, payload_z, irq;
2092 	u32 payload_index, payload_end_index, next_page_index;
2093 	int page, end_page, i, length, offset;
2094 
2095 	p = packet;
2096 	payload_index = payload;
2097 
2098 	if (p->skip)
2099 		z = 1;
2100 	else
2101 		z = 2;
2102 	if (p->header_length > 0)
2103 		z++;
2104 
2105 	/* Determine the first page the payload isn't contained in. */
2106 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2107 	if (p->payload_length > 0)
2108 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
2109 	else
2110 		payload_z = 0;
2111 
2112 	z += payload_z;
2113 
2114 	/* Get header size in number of descriptors. */
2115 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2116 
2117 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2118 	if (d == NULL)
2119 		return -ENOMEM;
2120 
2121 	if (!p->skip) {
2122 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2123 		d[0].req_count = cpu_to_le16(8);
2124 		/*
2125 		 * Link the skip address to this descriptor itself.  This causes
2126 		 * a context to skip a cycle whenever lost cycles or FIFO
2127 		 * overruns occur, without dropping the data.  The application
2128 		 * should then decide whether this is an error condition or not.
2129 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
2130 		 */
2131 		d[0].branch_address = cpu_to_le32(d_bus | z);
2132 
2133 		header = (__le32 *) &d[1];
2134 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2135 					IT_HEADER_TAG(p->tag) |
2136 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2137 					IT_HEADER_CHANNEL(ctx->base.channel) |
2138 					IT_HEADER_SPEED(ctx->base.speed));
2139 		header[1] =
2140 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2141 							  p->payload_length));
2142 	}
2143 
2144 	if (p->header_length > 0) {
2145 		d[2].req_count    = cpu_to_le16(p->header_length);
2146 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2147 		memcpy(&d[z], p->header, p->header_length);
2148 	}
2149 
2150 	pd = d + z - payload_z;
2151 	payload_end_index = payload_index + p->payload_length;
2152 	for (i = 0; i < payload_z; i++) {
2153 		page               = payload_index >> PAGE_SHIFT;
2154 		offset             = payload_index & ~PAGE_MASK;
2155 		next_page_index    = (page + 1) << PAGE_SHIFT;
2156 		length             =
2157 			min(next_page_index, payload_end_index) - payload_index;
2158 		pd[i].req_count    = cpu_to_le16(length);
2159 
2160 		page_bus = page_private(buffer->pages[page]);
2161 		pd[i].data_address = cpu_to_le32(page_bus + offset);
2162 
2163 		payload_index += length;
2164 	}
2165 
2166 	if (p->interrupt)
2167 		irq = DESCRIPTOR_IRQ_ALWAYS;
2168 	else
2169 		irq = DESCRIPTOR_NO_IRQ;
2170 
2171 	last = z == 2 ? d : d + z - 1;
2172 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2173 				     DESCRIPTOR_STATUS |
2174 				     DESCRIPTOR_BRANCH_ALWAYS |
2175 				     irq);
2176 
2177 	context_append(&ctx->context, d, z, header_z);
2178 
2179 	return 0;
2180 }
2181 
2182 static int ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base,
2183 					struct fw_iso_packet *packet,
2184 					struct fw_iso_buffer *buffer,
2185 					unsigned long payload)
2186 {
2187 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2188 	struct descriptor *d, *pd;
2189 	struct fw_iso_packet *p = packet;
2190 	dma_addr_t d_bus, page_bus;
2191 	u32 z, header_z, rest;
2192 	int i, j, length;
2193 	int page, offset, packet_count, header_size, payload_per_buffer;
2194 
2195 	/*
2196 	 * The OHCI controller puts the isochronous header and trailer in the
2197 	 * buffer, so we need at least 8 bytes.
2198 	 */
2199 	packet_count = p->header_length / ctx->base.header_size;
2200 	header_size  = max(ctx->base.header_size, (size_t)8);
2201 
2202 	/* Get header size in number of descriptors. */
2203 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2204 	page     = payload >> PAGE_SHIFT;
2205 	offset   = payload & ~PAGE_MASK;
2206 	payload_per_buffer = p->payload_length / packet_count;
2207 
2208 	for (i = 0; i < packet_count; i++) {
2209 		/* d points to the header descriptor */
2210 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
2211 		d = context_get_descriptors(&ctx->context,
2212 				z + header_z, &d_bus);
2213 		if (d == NULL)
2214 			return -ENOMEM;
2215 
2216 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
2217 					      DESCRIPTOR_INPUT_MORE);
2218 		if (p->skip && i == 0)
2219 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2220 		d->req_count    = cpu_to_le16(header_size);
2221 		d->res_count    = d->req_count;
2222 		d->transfer_status = 0;
2223 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
2224 
2225 		rest = payload_per_buffer;
2226 		pd = d;
2227 		for (j = 1; j < z; j++) {
2228 			pd++;
2229 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2230 						  DESCRIPTOR_INPUT_MORE);
2231 
2232 			if (offset + rest < PAGE_SIZE)
2233 				length = rest;
2234 			else
2235 				length = PAGE_SIZE - offset;
2236 			pd->req_count = cpu_to_le16(length);
2237 			pd->res_count = pd->req_count;
2238 			pd->transfer_status = 0;
2239 
2240 			page_bus = page_private(buffer->pages[page]);
2241 			pd->data_address = cpu_to_le32(page_bus + offset);
2242 
2243 			offset = (offset + length) & ~PAGE_MASK;
2244 			rest -= length;
2245 			if (offset == 0)
2246 				page++;
2247 		}
2248 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2249 					  DESCRIPTOR_INPUT_LAST |
2250 					  DESCRIPTOR_BRANCH_ALWAYS);
2251 		if (p->interrupt && i == packet_count - 1)
2252 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2253 
2254 		context_append(&ctx->context, d, z, header_z);
2255 	}
2256 
2257 	return 0;
2258 }
2259 
2260 static int ohci_queue_iso(struct fw_iso_context *base,
2261 			  struct fw_iso_packet *packet,
2262 			  struct fw_iso_buffer *buffer,
2263 			  unsigned long payload)
2264 {
2265 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2266 	unsigned long flags;
2267 	int ret;
2268 
2269 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
2270 	if (base->type == FW_ISO_CONTEXT_TRANSMIT)
2271 		ret = ohci_queue_iso_transmit(base, packet, buffer, payload);
2272 	else
2273 		ret = ohci_queue_iso_receive_packet_per_buffer(base, packet,
2274 							buffer, payload);
2275 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
2276 
2277 	return ret;
2278 }
2279 
2280 static const struct fw_card_driver ohci_driver = {
2281 	.enable			= ohci_enable,
2282 	.update_phy_reg		= ohci_update_phy_reg,
2283 	.set_config_rom		= ohci_set_config_rom,
2284 	.send_request		= ohci_send_request,
2285 	.send_response		= ohci_send_response,
2286 	.cancel_packet		= ohci_cancel_packet,
2287 	.enable_phys_dma	= ohci_enable_phys_dma,
2288 	.get_cycle_time		= ohci_get_cycle_time,
2289 
2290 	.allocate_iso_context	= ohci_allocate_iso_context,
2291 	.free_iso_context	= ohci_free_iso_context,
2292 	.queue_iso		= ohci_queue_iso,
2293 	.start_iso		= ohci_start_iso,
2294 	.stop_iso		= ohci_stop_iso,
2295 };
2296 
2297 #ifdef CONFIG_PPC_PMAC
2298 static void ohci_pmac_on(struct pci_dev *dev)
2299 {
2300 	if (machine_is(powermac)) {
2301 		struct device_node *ofn = pci_device_to_OF_node(dev);
2302 
2303 		if (ofn) {
2304 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
2305 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
2306 		}
2307 	}
2308 }
2309 
2310 static void ohci_pmac_off(struct pci_dev *dev)
2311 {
2312 	if (machine_is(powermac)) {
2313 		struct device_node *ofn = pci_device_to_OF_node(dev);
2314 
2315 		if (ofn) {
2316 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
2317 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
2318 		}
2319 	}
2320 }
2321 #else
2322 #define ohci_pmac_on(dev)
2323 #define ohci_pmac_off(dev)
2324 #endif /* CONFIG_PPC_PMAC */
2325 
2326 static int __devinit pci_probe(struct pci_dev *dev,
2327 			       const struct pci_device_id *ent)
2328 {
2329 	struct fw_ohci *ohci;
2330 	u32 bus_options, max_receive, link_speed, version;
2331 	u64 guid;
2332 	int i, err, n_ir, n_it;
2333 	size_t size;
2334 
2335 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
2336 	if (ohci == NULL) {
2337 		err = -ENOMEM;
2338 		goto fail;
2339 	}
2340 
2341 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
2342 
2343 	ohci_pmac_on(dev);
2344 
2345 	err = pci_enable_device(dev);
2346 	if (err) {
2347 		fw_error("Failed to enable OHCI hardware\n");
2348 		goto fail_free;
2349 	}
2350 
2351 	pci_set_master(dev);
2352 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
2353 	pci_set_drvdata(dev, ohci);
2354 
2355 	spin_lock_init(&ohci->lock);
2356 
2357 	tasklet_init(&ohci->bus_reset_tasklet,
2358 		     bus_reset_tasklet, (unsigned long)ohci);
2359 
2360 	err = pci_request_region(dev, 0, ohci_driver_name);
2361 	if (err) {
2362 		fw_error("MMIO resource unavailable\n");
2363 		goto fail_disable;
2364 	}
2365 
2366 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
2367 	if (ohci->registers == NULL) {
2368 		fw_error("Failed to remap registers\n");
2369 		err = -ENXIO;
2370 		goto fail_iomem;
2371 	}
2372 
2373 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
2374 		if (ohci_quirks[i].vendor == dev->vendor &&
2375 		    (ohci_quirks[i].device == dev->device ||
2376 		     ohci_quirks[i].device == (unsigned short)PCI_ANY_ID)) {
2377 			ohci->quirks = ohci_quirks[i].flags;
2378 			break;
2379 		}
2380 	if (param_quirks)
2381 		ohci->quirks = param_quirks;
2382 
2383 	ar_context_init(&ohci->ar_request_ctx, ohci,
2384 			OHCI1394_AsReqRcvContextControlSet);
2385 
2386 	ar_context_init(&ohci->ar_response_ctx, ohci,
2387 			OHCI1394_AsRspRcvContextControlSet);
2388 
2389 	context_init(&ohci->at_request_ctx, ohci,
2390 		     OHCI1394_AsReqTrContextControlSet, handle_at_packet);
2391 
2392 	context_init(&ohci->at_response_ctx, ohci,
2393 		     OHCI1394_AsRspTrContextControlSet, handle_at_packet);
2394 
2395 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
2396 	ohci->ir_context_channels = ~0ULL;
2397 	ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
2398 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
2399 	n_ir = hweight32(ohci->ir_context_mask);
2400 	size = sizeof(struct iso_context) * n_ir;
2401 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
2402 
2403 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
2404 	ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
2405 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
2406 	n_it = hweight32(ohci->it_context_mask);
2407 	size = sizeof(struct iso_context) * n_it;
2408 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
2409 
2410 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
2411 		err = -ENOMEM;
2412 		goto fail_contexts;
2413 	}
2414 
2415 	/* self-id dma buffer allocation */
2416 	ohci->self_id_cpu = dma_alloc_coherent(ohci->card.device,
2417 					       SELF_ID_BUF_SIZE,
2418 					       &ohci->self_id_bus,
2419 					       GFP_KERNEL);
2420 	if (ohci->self_id_cpu == NULL) {
2421 		err = -ENOMEM;
2422 		goto fail_contexts;
2423 	}
2424 
2425 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
2426 	max_receive = (bus_options >> 12) & 0xf;
2427 	link_speed = bus_options & 0x7;
2428 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
2429 		reg_read(ohci, OHCI1394_GUIDLo);
2430 
2431 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
2432 	if (err)
2433 		goto fail_self_id;
2434 
2435 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2436 	fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
2437 		  "%d IR + %d IT contexts, quirks 0x%x\n",
2438 		  dev_name(&dev->dev), version >> 16, version & 0xff,
2439 		  n_ir, n_it, ohci->quirks);
2440 
2441 	return 0;
2442 
2443  fail_self_id:
2444 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2445 			  ohci->self_id_cpu, ohci->self_id_bus);
2446  fail_contexts:
2447 	kfree(ohci->ir_context_list);
2448 	kfree(ohci->it_context_list);
2449 	context_release(&ohci->at_response_ctx);
2450 	context_release(&ohci->at_request_ctx);
2451 	ar_context_release(&ohci->ar_response_ctx);
2452 	ar_context_release(&ohci->ar_request_ctx);
2453 	pci_iounmap(dev, ohci->registers);
2454  fail_iomem:
2455 	pci_release_region(dev, 0);
2456  fail_disable:
2457 	pci_disable_device(dev);
2458  fail_free:
2459 	kfree(&ohci->card);
2460 	ohci_pmac_off(dev);
2461  fail:
2462 	if (err == -ENOMEM)
2463 		fw_error("Out of memory\n");
2464 
2465 	return err;
2466 }
2467 
2468 static void pci_remove(struct pci_dev *dev)
2469 {
2470 	struct fw_ohci *ohci;
2471 
2472 	ohci = pci_get_drvdata(dev);
2473 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2474 	flush_writes(ohci);
2475 	fw_core_remove_card(&ohci->card);
2476 
2477 	/*
2478 	 * FIXME: Fail all pending packets here, now that the upper
2479 	 * layers can't queue any more.
2480 	 */
2481 
2482 	software_reset(ohci);
2483 	free_irq(dev->irq, ohci);
2484 
2485 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
2486 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2487 				  ohci->next_config_rom, ohci->next_config_rom_bus);
2488 	if (ohci->config_rom)
2489 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2490 				  ohci->config_rom, ohci->config_rom_bus);
2491 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2492 			  ohci->self_id_cpu, ohci->self_id_bus);
2493 	ar_context_release(&ohci->ar_request_ctx);
2494 	ar_context_release(&ohci->ar_response_ctx);
2495 	context_release(&ohci->at_request_ctx);
2496 	context_release(&ohci->at_response_ctx);
2497 	kfree(ohci->it_context_list);
2498 	kfree(ohci->ir_context_list);
2499 	pci_iounmap(dev, ohci->registers);
2500 	pci_release_region(dev, 0);
2501 	pci_disable_device(dev);
2502 	kfree(&ohci->card);
2503 	ohci_pmac_off(dev);
2504 
2505 	fw_notify("Removed fw-ohci device.\n");
2506 }
2507 
2508 #ifdef CONFIG_PM
2509 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
2510 {
2511 	struct fw_ohci *ohci = pci_get_drvdata(dev);
2512 	int err;
2513 
2514 	software_reset(ohci);
2515 	free_irq(dev->irq, ohci);
2516 	err = pci_save_state(dev);
2517 	if (err) {
2518 		fw_error("pci_save_state failed\n");
2519 		return err;
2520 	}
2521 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
2522 	if (err)
2523 		fw_error("pci_set_power_state failed with %d\n", err);
2524 	ohci_pmac_off(dev);
2525 
2526 	return 0;
2527 }
2528 
2529 static int pci_resume(struct pci_dev *dev)
2530 {
2531 	struct fw_ohci *ohci = pci_get_drvdata(dev);
2532 	int err;
2533 
2534 	ohci_pmac_on(dev);
2535 	pci_set_power_state(dev, PCI_D0);
2536 	pci_restore_state(dev);
2537 	err = pci_enable_device(dev);
2538 	if (err) {
2539 		fw_error("pci_enable_device failed\n");
2540 		return err;
2541 	}
2542 
2543 	return ohci_enable(&ohci->card, NULL, 0);
2544 }
2545 #endif
2546 
2547 static const struct pci_device_id pci_table[] = {
2548 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
2549 	{ }
2550 };
2551 
2552 MODULE_DEVICE_TABLE(pci, pci_table);
2553 
2554 static struct pci_driver fw_ohci_pci_driver = {
2555 	.name		= ohci_driver_name,
2556 	.id_table	= pci_table,
2557 	.probe		= pci_probe,
2558 	.remove		= pci_remove,
2559 #ifdef CONFIG_PM
2560 	.resume		= pci_resume,
2561 	.suspend	= pci_suspend,
2562 #endif
2563 };
2564 
2565 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
2566 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
2567 MODULE_LICENSE("GPL");
2568 
2569 /* Provide a module alias so root-on-sbp2 initrds don't break. */
2570 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
2571 MODULE_ALIAS("ohci1394");
2572 #endif
2573 
2574 static int __init fw_ohci_init(void)
2575 {
2576 	return pci_register_driver(&fw_ohci_pci_driver);
2577 }
2578 
2579 static void __exit fw_ohci_cleanup(void)
2580 {
2581 	pci_unregister_driver(&fw_ohci_pci_driver);
2582 }
2583 
2584 module_init(fw_ohci_init);
2585 module_exit(fw_ohci_cleanup);
2586