xref: /openbmc/linux/drivers/firewire/ohci.c (revision fd589a8f)
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/atomic.h>
42 #include <asm/byteorder.h>
43 #include <asm/page.h>
44 #include <asm/system.h>
45 
46 #ifdef CONFIG_PPC_PMAC
47 #include <asm/pmac_feature.h>
48 #endif
49 
50 #include "core.h"
51 #include "ohci.h"
52 
53 #define DESCRIPTOR_OUTPUT_MORE		0
54 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
55 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
56 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
57 #define DESCRIPTOR_STATUS		(1 << 11)
58 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
59 #define DESCRIPTOR_PING			(1 << 7)
60 #define DESCRIPTOR_YY			(1 << 6)
61 #define DESCRIPTOR_NO_IRQ		(0 << 4)
62 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
63 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
64 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
65 #define DESCRIPTOR_WAIT			(3 << 0)
66 
67 struct descriptor {
68 	__le16 req_count;
69 	__le16 control;
70 	__le32 data_address;
71 	__le32 branch_address;
72 	__le16 res_count;
73 	__le16 transfer_status;
74 } __attribute__((aligned(16)));
75 
76 struct db_descriptor {
77 	__le16 first_size;
78 	__le16 control;
79 	__le16 second_req_count;
80 	__le16 first_req_count;
81 	__le32 branch_address;
82 	__le16 second_res_count;
83 	__le16 first_res_count;
84 	__le32 reserved0;
85 	__le32 first_buffer;
86 	__le32 second_buffer;
87 	__le32 reserved1;
88 } __attribute__((aligned(16)));
89 
90 #define CONTROL_SET(regs)	(regs)
91 #define CONTROL_CLEAR(regs)	((regs) + 4)
92 #define COMMAND_PTR(regs)	((regs) + 12)
93 #define CONTEXT_MATCH(regs)	((regs) + 16)
94 
95 struct ar_buffer {
96 	struct descriptor descriptor;
97 	struct ar_buffer *next;
98 	__le32 data[0];
99 };
100 
101 struct ar_context {
102 	struct fw_ohci *ohci;
103 	struct ar_buffer *current_buffer;
104 	struct ar_buffer *last_buffer;
105 	void *pointer;
106 	u32 regs;
107 	struct tasklet_struct tasklet;
108 };
109 
110 struct context;
111 
112 typedef int (*descriptor_callback_t)(struct context *ctx,
113 				     struct descriptor *d,
114 				     struct descriptor *last);
115 
116 /*
117  * A buffer that contains a block of DMA-able coherent memory used for
118  * storing a portion of a DMA descriptor program.
119  */
120 struct descriptor_buffer {
121 	struct list_head list;
122 	dma_addr_t buffer_bus;
123 	size_t buffer_size;
124 	size_t used;
125 	struct descriptor buffer[0];
126 };
127 
128 struct context {
129 	struct fw_ohci *ohci;
130 	u32 regs;
131 	int total_allocation;
132 
133 	/*
134 	 * List of page-sized buffers for storing DMA descriptors.
135 	 * Head of list contains buffers in use and tail of list contains
136 	 * free buffers.
137 	 */
138 	struct list_head buffer_list;
139 
140 	/*
141 	 * Pointer to a buffer inside buffer_list that contains the tail
142 	 * end of the current DMA program.
143 	 */
144 	struct descriptor_buffer *buffer_tail;
145 
146 	/*
147 	 * The descriptor containing the branch address of the first
148 	 * descriptor that has not yet been filled by the device.
149 	 */
150 	struct descriptor *last;
151 
152 	/*
153 	 * The last descriptor in the DMA program.  It contains the branch
154 	 * address that must be updated upon appending a new descriptor.
155 	 */
156 	struct descriptor *prev;
157 
158 	descriptor_callback_t callback;
159 
160 	struct tasklet_struct tasklet;
161 };
162 
163 #define IT_HEADER_SY(v)          ((v) <<  0)
164 #define IT_HEADER_TCODE(v)       ((v) <<  4)
165 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
166 #define IT_HEADER_TAG(v)         ((v) << 14)
167 #define IT_HEADER_SPEED(v)       ((v) << 16)
168 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
169 
170 struct iso_context {
171 	struct fw_iso_context base;
172 	struct context context;
173 	int excess_bytes;
174 	void *header;
175 	size_t header_length;
176 };
177 
178 #define CONFIG_ROM_SIZE 1024
179 
180 struct fw_ohci {
181 	struct fw_card card;
182 
183 	__iomem char *registers;
184 	dma_addr_t self_id_bus;
185 	__le32 *self_id_cpu;
186 	struct tasklet_struct bus_reset_tasklet;
187 	int node_id;
188 	int generation;
189 	int request_generation;	/* for timestamping incoming requests */
190 	atomic_t bus_seconds;
191 
192 	bool use_dualbuffer;
193 	bool old_uninorth;
194 	bool bus_reset_packet_quirk;
195 
196 	/*
197 	 * Spinlock for accessing fw_ohci data.  Never call out of
198 	 * this driver with this lock held.
199 	 */
200 	spinlock_t lock;
201 	u32 self_id_buffer[512];
202 
203 	/* Config rom buffers */
204 	__be32 *config_rom;
205 	dma_addr_t config_rom_bus;
206 	__be32 *next_config_rom;
207 	dma_addr_t next_config_rom_bus;
208 	u32 next_header;
209 
210 	struct ar_context ar_request_ctx;
211 	struct ar_context ar_response_ctx;
212 	struct context at_request_ctx;
213 	struct context at_response_ctx;
214 
215 	u32 it_context_mask;
216 	struct iso_context *it_context_list;
217 	u64 ir_context_channels;
218 	u32 ir_context_mask;
219 	struct iso_context *ir_context_list;
220 };
221 
222 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
223 {
224 	return container_of(card, struct fw_ohci, card);
225 }
226 
227 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
228 #define IR_CONTEXT_BUFFER_FILL		0x80000000
229 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
230 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
231 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
232 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
233 
234 #define CONTEXT_RUN	0x8000
235 #define CONTEXT_WAKE	0x1000
236 #define CONTEXT_DEAD	0x0800
237 #define CONTEXT_ACTIVE	0x0400
238 
239 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
240 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
241 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
242 
243 #define OHCI1394_REGISTER_SIZE		0x800
244 #define OHCI_LOOP_COUNT			500
245 #define OHCI1394_PCI_HCI_Control	0x40
246 #define SELF_ID_BUF_SIZE		0x800
247 #define OHCI_TCODE_PHY_PACKET		0x0e
248 #define OHCI_VERSION_1_1		0x010010
249 
250 static char ohci_driver_name[] = KBUILD_MODNAME;
251 
252 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
253 
254 #define OHCI_PARAM_DEBUG_AT_AR		1
255 #define OHCI_PARAM_DEBUG_SELFIDS	2
256 #define OHCI_PARAM_DEBUG_IRQS		4
257 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
258 
259 static int param_debug;
260 module_param_named(debug, param_debug, int, 0644);
261 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
262 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
263 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
264 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
265 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
266 	", or a combination, or all = -1)");
267 
268 static void log_irqs(u32 evt)
269 {
270 	if (likely(!(param_debug &
271 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
272 		return;
273 
274 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
275 	    !(evt & OHCI1394_busReset))
276 		return;
277 
278 	fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
279 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
280 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
281 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
282 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
283 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
284 	    evt & OHCI1394_isochRx		? " IR"			: "",
285 	    evt & OHCI1394_isochTx		? " IT"			: "",
286 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
287 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
288 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
289 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
290 	    evt & OHCI1394_busReset		? " busReset"		: "",
291 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
292 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
293 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
294 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
295 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
296 		    OHCI1394_regAccessFail | OHCI1394_busReset)
297 						? " ?"			: "");
298 }
299 
300 static const char *speed[] = {
301 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
302 };
303 static const char *power[] = {
304 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
305 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
306 };
307 static const char port[] = { '.', '-', 'p', 'c', };
308 
309 static char _p(u32 *s, int shift)
310 {
311 	return port[*s >> shift & 3];
312 }
313 
314 static void log_selfids(int node_id, int generation, int self_id_count, u32 *s)
315 {
316 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
317 		return;
318 
319 	fw_notify("%d selfIDs, generation %d, local node ID %04x\n",
320 		  self_id_count, generation, node_id);
321 
322 	for (; self_id_count--; ++s)
323 		if ((*s & 1 << 23) == 0)
324 			fw_notify("selfID 0: %08x, phy %d [%c%c%c] "
325 			    "%s gc=%d %s %s%s%s\n",
326 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
327 			    speed[*s >> 14 & 3], *s >> 16 & 63,
328 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
329 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
330 		else
331 			fw_notify("selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
332 			    *s, *s >> 24 & 63,
333 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
334 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
335 }
336 
337 static const char *evts[] = {
338 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
339 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
340 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
341 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
342 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
343 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
344 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
345 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
346 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
347 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
348 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
349 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
350 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
351 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
352 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
353 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
354 	[0x20] = "pending/cancelled",
355 };
356 static const char *tcodes[] = {
357 	[0x0] = "QW req",		[0x1] = "BW req",
358 	[0x2] = "W resp",		[0x3] = "-reserved-",
359 	[0x4] = "QR req",		[0x5] = "BR req",
360 	[0x6] = "QR resp",		[0x7] = "BR resp",
361 	[0x8] = "cycle start",		[0x9] = "Lk req",
362 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
363 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
364 	[0xe] = "link internal",	[0xf] = "-reserved-",
365 };
366 static const char *phys[] = {
367 	[0x0] = "phy config packet",	[0x1] = "link-on packet",
368 	[0x2] = "self-id packet",	[0x3] = "-reserved-",
369 };
370 
371 static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
372 {
373 	int tcode = header[0] >> 4 & 0xf;
374 	char specific[12];
375 
376 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
377 		return;
378 
379 	if (unlikely(evt >= ARRAY_SIZE(evts)))
380 			evt = 0x1f;
381 
382 	if (evt == OHCI1394_evt_bus_reset) {
383 		fw_notify("A%c evt_bus_reset, generation %d\n",
384 		    dir, (header[2] >> 16) & 0xff);
385 		return;
386 	}
387 
388 	if (header[0] == ~header[1]) {
389 		fw_notify("A%c %s, %s, %08x\n",
390 		    dir, evts[evt], phys[header[0] >> 30 & 0x3], header[0]);
391 		return;
392 	}
393 
394 	switch (tcode) {
395 	case 0x0: case 0x6: case 0x8:
396 		snprintf(specific, sizeof(specific), " = %08x",
397 			 be32_to_cpu((__force __be32)header[3]));
398 		break;
399 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
400 		snprintf(specific, sizeof(specific), " %x,%x",
401 			 header[3] >> 16, header[3] & 0xffff);
402 		break;
403 	default:
404 		specific[0] = '\0';
405 	}
406 
407 	switch (tcode) {
408 	case 0xe: case 0xa:
409 		fw_notify("A%c %s, %s\n", dir, evts[evt], tcodes[tcode]);
410 		break;
411 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
412 		fw_notify("A%c spd %x tl %02x, "
413 		    "%04x -> %04x, %s, "
414 		    "%s, %04x%08x%s\n",
415 		    dir, speed, header[0] >> 10 & 0x3f,
416 		    header[1] >> 16, header[0] >> 16, evts[evt],
417 		    tcodes[tcode], header[1] & 0xffff, header[2], specific);
418 		break;
419 	default:
420 		fw_notify("A%c spd %x tl %02x, "
421 		    "%04x -> %04x, %s, "
422 		    "%s%s\n",
423 		    dir, speed, header[0] >> 10 & 0x3f,
424 		    header[1] >> 16, header[0] >> 16, evts[evt],
425 		    tcodes[tcode], specific);
426 	}
427 }
428 
429 #else
430 
431 #define log_irqs(evt)
432 #define log_selfids(node_id, generation, self_id_count, sid)
433 #define log_ar_at_event(dir, speed, header, evt)
434 
435 #endif /* CONFIG_FIREWIRE_OHCI_DEBUG */
436 
437 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
438 {
439 	writel(data, ohci->registers + offset);
440 }
441 
442 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
443 {
444 	return readl(ohci->registers + offset);
445 }
446 
447 static inline void flush_writes(const struct fw_ohci *ohci)
448 {
449 	/* Do a dummy read to flush writes. */
450 	reg_read(ohci, OHCI1394_Version);
451 }
452 
453 static int ohci_update_phy_reg(struct fw_card *card, int addr,
454 			       int clear_bits, int set_bits)
455 {
456 	struct fw_ohci *ohci = fw_ohci(card);
457 	u32 val, old;
458 
459 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
460 	flush_writes(ohci);
461 	msleep(2);
462 	val = reg_read(ohci, OHCI1394_PhyControl);
463 	if ((val & OHCI1394_PhyControl_ReadDone) == 0) {
464 		fw_error("failed to set phy reg bits.\n");
465 		return -EBUSY;
466 	}
467 
468 	old = OHCI1394_PhyControl_ReadData(val);
469 	old = (old & ~clear_bits) | set_bits;
470 	reg_write(ohci, OHCI1394_PhyControl,
471 		  OHCI1394_PhyControl_Write(addr, old));
472 
473 	return 0;
474 }
475 
476 static int ar_context_add_page(struct ar_context *ctx)
477 {
478 	struct device *dev = ctx->ohci->card.device;
479 	struct ar_buffer *ab;
480 	dma_addr_t uninitialized_var(ab_bus);
481 	size_t offset;
482 
483 	ab = dma_alloc_coherent(dev, PAGE_SIZE, &ab_bus, GFP_ATOMIC);
484 	if (ab == NULL)
485 		return -ENOMEM;
486 
487 	ab->next = NULL;
488 	memset(&ab->descriptor, 0, sizeof(ab->descriptor));
489 	ab->descriptor.control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
490 						    DESCRIPTOR_STATUS |
491 						    DESCRIPTOR_BRANCH_ALWAYS);
492 	offset = offsetof(struct ar_buffer, data);
493 	ab->descriptor.req_count      = cpu_to_le16(PAGE_SIZE - offset);
494 	ab->descriptor.data_address   = cpu_to_le32(ab_bus + offset);
495 	ab->descriptor.res_count      = cpu_to_le16(PAGE_SIZE - offset);
496 	ab->descriptor.branch_address = 0;
497 
498 	ctx->last_buffer->descriptor.branch_address = cpu_to_le32(ab_bus | 1);
499 	ctx->last_buffer->next = ab;
500 	ctx->last_buffer = ab;
501 
502 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
503 	flush_writes(ctx->ohci);
504 
505 	return 0;
506 }
507 
508 static void ar_context_release(struct ar_context *ctx)
509 {
510 	struct ar_buffer *ab, *ab_next;
511 	size_t offset;
512 	dma_addr_t ab_bus;
513 
514 	for (ab = ctx->current_buffer; ab; ab = ab_next) {
515 		ab_next = ab->next;
516 		offset = offsetof(struct ar_buffer, data);
517 		ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
518 		dma_free_coherent(ctx->ohci->card.device, PAGE_SIZE,
519 				  ab, ab_bus);
520 	}
521 }
522 
523 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
524 #define cond_le32_to_cpu(v) \
525 	(ohci->old_uninorth ? (__force __u32)(v) : le32_to_cpu(v))
526 #else
527 #define cond_le32_to_cpu(v) le32_to_cpu(v)
528 #endif
529 
530 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
531 {
532 	struct fw_ohci *ohci = ctx->ohci;
533 	struct fw_packet p;
534 	u32 status, length, tcode;
535 	int evt;
536 
537 	p.header[0] = cond_le32_to_cpu(buffer[0]);
538 	p.header[1] = cond_le32_to_cpu(buffer[1]);
539 	p.header[2] = cond_le32_to_cpu(buffer[2]);
540 
541 	tcode = (p.header[0] >> 4) & 0x0f;
542 	switch (tcode) {
543 	case TCODE_WRITE_QUADLET_REQUEST:
544 	case TCODE_READ_QUADLET_RESPONSE:
545 		p.header[3] = (__force __u32) buffer[3];
546 		p.header_length = 16;
547 		p.payload_length = 0;
548 		break;
549 
550 	case TCODE_READ_BLOCK_REQUEST :
551 		p.header[3] = cond_le32_to_cpu(buffer[3]);
552 		p.header_length = 16;
553 		p.payload_length = 0;
554 		break;
555 
556 	case TCODE_WRITE_BLOCK_REQUEST:
557 	case TCODE_READ_BLOCK_RESPONSE:
558 	case TCODE_LOCK_REQUEST:
559 	case TCODE_LOCK_RESPONSE:
560 		p.header[3] = cond_le32_to_cpu(buffer[3]);
561 		p.header_length = 16;
562 		p.payload_length = p.header[3] >> 16;
563 		break;
564 
565 	case TCODE_WRITE_RESPONSE:
566 	case TCODE_READ_QUADLET_REQUEST:
567 	case OHCI_TCODE_PHY_PACKET:
568 		p.header_length = 12;
569 		p.payload_length = 0;
570 		break;
571 
572 	default:
573 		/* FIXME: Stop context, discard everything, and restart? */
574 		p.header_length = 0;
575 		p.payload_length = 0;
576 	}
577 
578 	p.payload = (void *) buffer + p.header_length;
579 
580 	/* FIXME: What to do about evt_* errors? */
581 	length = (p.header_length + p.payload_length + 3) / 4;
582 	status = cond_le32_to_cpu(buffer[length]);
583 	evt    = (status >> 16) & 0x1f;
584 
585 	p.ack        = evt - 16;
586 	p.speed      = (status >> 21) & 0x7;
587 	p.timestamp  = status & 0xffff;
588 	p.generation = ohci->request_generation;
589 
590 	log_ar_at_event('R', p.speed, p.header, evt);
591 
592 	/*
593 	 * The OHCI bus reset handler synthesizes a phy packet with
594 	 * the new generation number when a bus reset happens (see
595 	 * section 8.4.2.3).  This helps us determine when a request
596 	 * was received and make sure we send the response in the same
597 	 * generation.  We only need this for requests; for responses
598 	 * we use the unique tlabel for finding the matching
599 	 * request.
600 	 *
601 	 * Alas some chips sometimes emit bus reset packets with a
602 	 * wrong generation.  We set the correct generation for these
603 	 * at a slightly incorrect time (in bus_reset_tasklet).
604 	 */
605 	if (evt == OHCI1394_evt_bus_reset) {
606 		if (!ohci->bus_reset_packet_quirk)
607 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
608 	} else if (ctx == &ohci->ar_request_ctx) {
609 		fw_core_handle_request(&ohci->card, &p);
610 	} else {
611 		fw_core_handle_response(&ohci->card, &p);
612 	}
613 
614 	return buffer + length + 1;
615 }
616 
617 static void ar_context_tasklet(unsigned long data)
618 {
619 	struct ar_context *ctx = (struct ar_context *)data;
620 	struct fw_ohci *ohci = ctx->ohci;
621 	struct ar_buffer *ab;
622 	struct descriptor *d;
623 	void *buffer, *end;
624 
625 	ab = ctx->current_buffer;
626 	d = &ab->descriptor;
627 
628 	if (d->res_count == 0) {
629 		size_t size, rest, offset;
630 		dma_addr_t start_bus;
631 		void *start;
632 
633 		/*
634 		 * This descriptor is finished and we may have a
635 		 * packet split across this and the next buffer. We
636 		 * reuse the page for reassembling the split packet.
637 		 */
638 
639 		offset = offsetof(struct ar_buffer, data);
640 		start = buffer = ab;
641 		start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
642 
643 		ab = ab->next;
644 		d = &ab->descriptor;
645 		size = buffer + PAGE_SIZE - ctx->pointer;
646 		rest = le16_to_cpu(d->req_count) - le16_to_cpu(d->res_count);
647 		memmove(buffer, ctx->pointer, size);
648 		memcpy(buffer + size, ab->data, rest);
649 		ctx->current_buffer = ab;
650 		ctx->pointer = (void *) ab->data + rest;
651 		end = buffer + size + rest;
652 
653 		while (buffer < end)
654 			buffer = handle_ar_packet(ctx, buffer);
655 
656 		dma_free_coherent(ohci->card.device, PAGE_SIZE,
657 				  start, start_bus);
658 		ar_context_add_page(ctx);
659 	} else {
660 		buffer = ctx->pointer;
661 		ctx->pointer = end =
662 			(void *) ab + PAGE_SIZE - le16_to_cpu(d->res_count);
663 
664 		while (buffer < end)
665 			buffer = handle_ar_packet(ctx, buffer);
666 	}
667 }
668 
669 static int ar_context_init(struct ar_context *ctx,
670 			   struct fw_ohci *ohci, u32 regs)
671 {
672 	struct ar_buffer ab;
673 
674 	ctx->regs        = regs;
675 	ctx->ohci        = ohci;
676 	ctx->last_buffer = &ab;
677 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
678 
679 	ar_context_add_page(ctx);
680 	ar_context_add_page(ctx);
681 	ctx->current_buffer = ab.next;
682 	ctx->pointer = ctx->current_buffer->data;
683 
684 	return 0;
685 }
686 
687 static void ar_context_run(struct ar_context *ctx)
688 {
689 	struct ar_buffer *ab = ctx->current_buffer;
690 	dma_addr_t ab_bus;
691 	size_t offset;
692 
693 	offset = offsetof(struct ar_buffer, data);
694 	ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
695 
696 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ab_bus | 1);
697 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
698 	flush_writes(ctx->ohci);
699 }
700 
701 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
702 {
703 	int b, key;
704 
705 	b   = (le16_to_cpu(d->control) & DESCRIPTOR_BRANCH_ALWAYS) >> 2;
706 	key = (le16_to_cpu(d->control) & DESCRIPTOR_KEY_IMMEDIATE) >> 8;
707 
708 	/* figure out which descriptor the branch address goes in */
709 	if (z == 2 && (b == 3 || key == 2))
710 		return d;
711 	else
712 		return d + z - 1;
713 }
714 
715 static void context_tasklet(unsigned long data)
716 {
717 	struct context *ctx = (struct context *) data;
718 	struct descriptor *d, *last;
719 	u32 address;
720 	int z;
721 	struct descriptor_buffer *desc;
722 
723 	desc = list_entry(ctx->buffer_list.next,
724 			struct descriptor_buffer, list);
725 	last = ctx->last;
726 	while (last->branch_address != 0) {
727 		struct descriptor_buffer *old_desc = desc;
728 		address = le32_to_cpu(last->branch_address);
729 		z = address & 0xf;
730 		address &= ~0xf;
731 
732 		/* If the branch address points to a buffer outside of the
733 		 * current buffer, advance to the next buffer. */
734 		if (address < desc->buffer_bus ||
735 				address >= desc->buffer_bus + desc->used)
736 			desc = list_entry(desc->list.next,
737 					struct descriptor_buffer, list);
738 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
739 		last = find_branch_descriptor(d, z);
740 
741 		if (!ctx->callback(ctx, d, last))
742 			break;
743 
744 		if (old_desc != desc) {
745 			/* If we've advanced to the next buffer, move the
746 			 * previous buffer to the free list. */
747 			unsigned long flags;
748 			old_desc->used = 0;
749 			spin_lock_irqsave(&ctx->ohci->lock, flags);
750 			list_move_tail(&old_desc->list, &ctx->buffer_list);
751 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
752 		}
753 		ctx->last = last;
754 	}
755 }
756 
757 /*
758  * Allocate a new buffer and add it to the list of free buffers for this
759  * context.  Must be called with ohci->lock held.
760  */
761 static int context_add_buffer(struct context *ctx)
762 {
763 	struct descriptor_buffer *desc;
764 	dma_addr_t uninitialized_var(bus_addr);
765 	int offset;
766 
767 	/*
768 	 * 16MB of descriptors should be far more than enough for any DMA
769 	 * program.  This will catch run-away userspace or DoS attacks.
770 	 */
771 	if (ctx->total_allocation >= 16*1024*1024)
772 		return -ENOMEM;
773 
774 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
775 			&bus_addr, GFP_ATOMIC);
776 	if (!desc)
777 		return -ENOMEM;
778 
779 	offset = (void *)&desc->buffer - (void *)desc;
780 	desc->buffer_size = PAGE_SIZE - offset;
781 	desc->buffer_bus = bus_addr + offset;
782 	desc->used = 0;
783 
784 	list_add_tail(&desc->list, &ctx->buffer_list);
785 	ctx->total_allocation += PAGE_SIZE;
786 
787 	return 0;
788 }
789 
790 static int context_init(struct context *ctx, struct fw_ohci *ohci,
791 			u32 regs, descriptor_callback_t callback)
792 {
793 	ctx->ohci = ohci;
794 	ctx->regs = regs;
795 	ctx->total_allocation = 0;
796 
797 	INIT_LIST_HEAD(&ctx->buffer_list);
798 	if (context_add_buffer(ctx) < 0)
799 		return -ENOMEM;
800 
801 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
802 			struct descriptor_buffer, list);
803 
804 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
805 	ctx->callback = callback;
806 
807 	/*
808 	 * We put a dummy descriptor in the buffer that has a NULL
809 	 * branch address and looks like it's been sent.  That way we
810 	 * have a descriptor to append DMA programs to.
811 	 */
812 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
813 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
814 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
815 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
816 	ctx->last = ctx->buffer_tail->buffer;
817 	ctx->prev = ctx->buffer_tail->buffer;
818 
819 	return 0;
820 }
821 
822 static void context_release(struct context *ctx)
823 {
824 	struct fw_card *card = &ctx->ohci->card;
825 	struct descriptor_buffer *desc, *tmp;
826 
827 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
828 		dma_free_coherent(card->device, PAGE_SIZE, desc,
829 			desc->buffer_bus -
830 			((void *)&desc->buffer - (void *)desc));
831 }
832 
833 /* Must be called with ohci->lock held */
834 static struct descriptor *context_get_descriptors(struct context *ctx,
835 						  int z, dma_addr_t *d_bus)
836 {
837 	struct descriptor *d = NULL;
838 	struct descriptor_buffer *desc = ctx->buffer_tail;
839 
840 	if (z * sizeof(*d) > desc->buffer_size)
841 		return NULL;
842 
843 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
844 		/* No room for the descriptor in this buffer, so advance to the
845 		 * next one. */
846 
847 		if (desc->list.next == &ctx->buffer_list) {
848 			/* If there is no free buffer next in the list,
849 			 * allocate one. */
850 			if (context_add_buffer(ctx) < 0)
851 				return NULL;
852 		}
853 		desc = list_entry(desc->list.next,
854 				struct descriptor_buffer, list);
855 		ctx->buffer_tail = desc;
856 	}
857 
858 	d = desc->buffer + desc->used / sizeof(*d);
859 	memset(d, 0, z * sizeof(*d));
860 	*d_bus = desc->buffer_bus + desc->used;
861 
862 	return d;
863 }
864 
865 static void context_run(struct context *ctx, u32 extra)
866 {
867 	struct fw_ohci *ohci = ctx->ohci;
868 
869 	reg_write(ohci, COMMAND_PTR(ctx->regs),
870 		  le32_to_cpu(ctx->last->branch_address));
871 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
872 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
873 	flush_writes(ohci);
874 }
875 
876 static void context_append(struct context *ctx,
877 			   struct descriptor *d, int z, int extra)
878 {
879 	dma_addr_t d_bus;
880 	struct descriptor_buffer *desc = ctx->buffer_tail;
881 
882 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
883 
884 	desc->used += (z + extra) * sizeof(*d);
885 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
886 	ctx->prev = find_branch_descriptor(d, z);
887 
888 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
889 	flush_writes(ctx->ohci);
890 }
891 
892 static void context_stop(struct context *ctx)
893 {
894 	u32 reg;
895 	int i;
896 
897 	reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
898 	flush_writes(ctx->ohci);
899 
900 	for (i = 0; i < 10; i++) {
901 		reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
902 		if ((reg & CONTEXT_ACTIVE) == 0)
903 			return;
904 
905 		mdelay(1);
906 	}
907 	fw_error("Error: DMA context still active (0x%08x)\n", reg);
908 }
909 
910 struct driver_data {
911 	struct fw_packet *packet;
912 };
913 
914 /*
915  * This function apppends a packet to the DMA queue for transmission.
916  * Must always be called with the ochi->lock held to ensure proper
917  * generation handling and locking around packet queue manipulation.
918  */
919 static int at_context_queue_packet(struct context *ctx,
920 				   struct fw_packet *packet)
921 {
922 	struct fw_ohci *ohci = ctx->ohci;
923 	dma_addr_t d_bus, uninitialized_var(payload_bus);
924 	struct driver_data *driver_data;
925 	struct descriptor *d, *last;
926 	__le32 *header;
927 	int z, tcode;
928 	u32 reg;
929 
930 	d = context_get_descriptors(ctx, 4, &d_bus);
931 	if (d == NULL) {
932 		packet->ack = RCODE_SEND_ERROR;
933 		return -1;
934 	}
935 
936 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
937 	d[0].res_count = cpu_to_le16(packet->timestamp);
938 
939 	/*
940 	 * The DMA format for asyncronous link packets is different
941 	 * from the IEEE1394 layout, so shift the fields around
942 	 * accordingly.  If header_length is 8, it's a PHY packet, to
943 	 * which we need to prepend an extra quadlet.
944 	 */
945 
946 	header = (__le32 *) &d[1];
947 	switch (packet->header_length) {
948 	case 16:
949 	case 12:
950 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
951 					(packet->speed << 16));
952 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
953 					(packet->header[0] & 0xffff0000));
954 		header[2] = cpu_to_le32(packet->header[2]);
955 
956 		tcode = (packet->header[0] >> 4) & 0x0f;
957 		if (TCODE_IS_BLOCK_PACKET(tcode))
958 			header[3] = cpu_to_le32(packet->header[3]);
959 		else
960 			header[3] = (__force __le32) packet->header[3];
961 
962 		d[0].req_count = cpu_to_le16(packet->header_length);
963 		break;
964 
965 	case 8:
966 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
967 					(packet->speed << 16));
968 		header[1] = cpu_to_le32(packet->header[0]);
969 		header[2] = cpu_to_le32(packet->header[1]);
970 		d[0].req_count = cpu_to_le16(12);
971 		break;
972 
973 	case 4:
974 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
975 					(packet->speed << 16));
976 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
977 		d[0].req_count = cpu_to_le16(8);
978 		break;
979 
980 	default:
981 		/* BUG(); */
982 		packet->ack = RCODE_SEND_ERROR;
983 		return -1;
984 	}
985 
986 	driver_data = (struct driver_data *) &d[3];
987 	driver_data->packet = packet;
988 	packet->driver_data = driver_data;
989 
990 	if (packet->payload_length > 0) {
991 		payload_bus =
992 			dma_map_single(ohci->card.device, packet->payload,
993 				       packet->payload_length, DMA_TO_DEVICE);
994 		if (dma_mapping_error(ohci->card.device, payload_bus)) {
995 			packet->ack = RCODE_SEND_ERROR;
996 			return -1;
997 		}
998 		packet->payload_bus = payload_bus;
999 
1000 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1001 		d[2].data_address = cpu_to_le32(payload_bus);
1002 		last = &d[2];
1003 		z = 3;
1004 	} else {
1005 		last = &d[0];
1006 		z = 2;
1007 	}
1008 
1009 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1010 				     DESCRIPTOR_IRQ_ALWAYS |
1011 				     DESCRIPTOR_BRANCH_ALWAYS);
1012 
1013 	/*
1014 	 * If the controller and packet generations don't match, we need to
1015 	 * bail out and try again.  If IntEvent.busReset is set, the AT context
1016 	 * is halted, so appending to the context and trying to run it is
1017 	 * futile.  Most controllers do the right thing and just flush the AT
1018 	 * queue (per section 7.2.3.2 of the OHCI 1.1 specification), but
1019 	 * some controllers (like a JMicron JMB381 PCI-e) misbehave and wind
1020 	 * up stalling out.  So we just bail out in software and try again
1021 	 * later, and everyone is happy.
1022 	 * FIXME: Document how the locking works.
1023 	 */
1024 	if (ohci->generation != packet->generation ||
1025 	    reg_read(ohci, OHCI1394_IntEventSet) & OHCI1394_busReset) {
1026 		if (packet->payload_length > 0)
1027 			dma_unmap_single(ohci->card.device, payload_bus,
1028 					 packet->payload_length, DMA_TO_DEVICE);
1029 		packet->ack = RCODE_GENERATION;
1030 		return -1;
1031 	}
1032 
1033 	context_append(ctx, d, z, 4 - z);
1034 
1035 	/* If the context isn't already running, start it up. */
1036 	reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1037 	if ((reg & CONTEXT_RUN) == 0)
1038 		context_run(ctx, 0);
1039 
1040 	return 0;
1041 }
1042 
1043 static int handle_at_packet(struct context *context,
1044 			    struct descriptor *d,
1045 			    struct descriptor *last)
1046 {
1047 	struct driver_data *driver_data;
1048 	struct fw_packet *packet;
1049 	struct fw_ohci *ohci = context->ohci;
1050 	int evt;
1051 
1052 	if (last->transfer_status == 0)
1053 		/* This descriptor isn't done yet, stop iteration. */
1054 		return 0;
1055 
1056 	driver_data = (struct driver_data *) &d[3];
1057 	packet = driver_data->packet;
1058 	if (packet == NULL)
1059 		/* This packet was cancelled, just continue. */
1060 		return 1;
1061 
1062 	if (packet->payload_bus)
1063 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1064 				 packet->payload_length, DMA_TO_DEVICE);
1065 
1066 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1067 	packet->timestamp = le16_to_cpu(last->res_count);
1068 
1069 	log_ar_at_event('T', packet->speed, packet->header, evt);
1070 
1071 	switch (evt) {
1072 	case OHCI1394_evt_timeout:
1073 		/* Async response transmit timed out. */
1074 		packet->ack = RCODE_CANCELLED;
1075 		break;
1076 
1077 	case OHCI1394_evt_flushed:
1078 		/*
1079 		 * The packet was flushed should give same error as
1080 		 * when we try to use a stale generation count.
1081 		 */
1082 		packet->ack = RCODE_GENERATION;
1083 		break;
1084 
1085 	case OHCI1394_evt_missing_ack:
1086 		/*
1087 		 * Using a valid (current) generation count, but the
1088 		 * node is not on the bus or not sending acks.
1089 		 */
1090 		packet->ack = RCODE_NO_ACK;
1091 		break;
1092 
1093 	case ACK_COMPLETE + 0x10:
1094 	case ACK_PENDING + 0x10:
1095 	case ACK_BUSY_X + 0x10:
1096 	case ACK_BUSY_A + 0x10:
1097 	case ACK_BUSY_B + 0x10:
1098 	case ACK_DATA_ERROR + 0x10:
1099 	case ACK_TYPE_ERROR + 0x10:
1100 		packet->ack = evt - 0x10;
1101 		break;
1102 
1103 	default:
1104 		packet->ack = RCODE_SEND_ERROR;
1105 		break;
1106 	}
1107 
1108 	packet->callback(packet, &ohci->card, packet->ack);
1109 
1110 	return 1;
1111 }
1112 
1113 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1114 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1115 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1116 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1117 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1118 
1119 static void handle_local_rom(struct fw_ohci *ohci,
1120 			     struct fw_packet *packet, u32 csr)
1121 {
1122 	struct fw_packet response;
1123 	int tcode, length, i;
1124 
1125 	tcode = HEADER_GET_TCODE(packet->header[0]);
1126 	if (TCODE_IS_BLOCK_PACKET(tcode))
1127 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1128 	else
1129 		length = 4;
1130 
1131 	i = csr - CSR_CONFIG_ROM;
1132 	if (i + length > CONFIG_ROM_SIZE) {
1133 		fw_fill_response(&response, packet->header,
1134 				 RCODE_ADDRESS_ERROR, NULL, 0);
1135 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1136 		fw_fill_response(&response, packet->header,
1137 				 RCODE_TYPE_ERROR, NULL, 0);
1138 	} else {
1139 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1140 				 (void *) ohci->config_rom + i, length);
1141 	}
1142 
1143 	fw_core_handle_response(&ohci->card, &response);
1144 }
1145 
1146 static void handle_local_lock(struct fw_ohci *ohci,
1147 			      struct fw_packet *packet, u32 csr)
1148 {
1149 	struct fw_packet response;
1150 	int tcode, length, ext_tcode, sel;
1151 	__be32 *payload, lock_old;
1152 	u32 lock_arg, lock_data;
1153 
1154 	tcode = HEADER_GET_TCODE(packet->header[0]);
1155 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1156 	payload = packet->payload;
1157 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1158 
1159 	if (tcode == TCODE_LOCK_REQUEST &&
1160 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1161 		lock_arg = be32_to_cpu(payload[0]);
1162 		lock_data = be32_to_cpu(payload[1]);
1163 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1164 		lock_arg = 0;
1165 		lock_data = 0;
1166 	} else {
1167 		fw_fill_response(&response, packet->header,
1168 				 RCODE_TYPE_ERROR, NULL, 0);
1169 		goto out;
1170 	}
1171 
1172 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1173 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1174 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1175 	reg_write(ohci, OHCI1394_CSRControl, sel);
1176 
1177 	if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000)
1178 		lock_old = cpu_to_be32(reg_read(ohci, OHCI1394_CSRData));
1179 	else
1180 		fw_notify("swap not done yet\n");
1181 
1182 	fw_fill_response(&response, packet->header,
1183 			 RCODE_COMPLETE, &lock_old, sizeof(lock_old));
1184  out:
1185 	fw_core_handle_response(&ohci->card, &response);
1186 }
1187 
1188 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1189 {
1190 	u64 offset;
1191 	u32 csr;
1192 
1193 	if (ctx == &ctx->ohci->at_request_ctx) {
1194 		packet->ack = ACK_PENDING;
1195 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1196 	}
1197 
1198 	offset =
1199 		((unsigned long long)
1200 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1201 		packet->header[2];
1202 	csr = offset - CSR_REGISTER_BASE;
1203 
1204 	/* Handle config rom reads. */
1205 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1206 		handle_local_rom(ctx->ohci, packet, csr);
1207 	else switch (csr) {
1208 	case CSR_BUS_MANAGER_ID:
1209 	case CSR_BANDWIDTH_AVAILABLE:
1210 	case CSR_CHANNELS_AVAILABLE_HI:
1211 	case CSR_CHANNELS_AVAILABLE_LO:
1212 		handle_local_lock(ctx->ohci, packet, csr);
1213 		break;
1214 	default:
1215 		if (ctx == &ctx->ohci->at_request_ctx)
1216 			fw_core_handle_request(&ctx->ohci->card, packet);
1217 		else
1218 			fw_core_handle_response(&ctx->ohci->card, packet);
1219 		break;
1220 	}
1221 
1222 	if (ctx == &ctx->ohci->at_response_ctx) {
1223 		packet->ack = ACK_COMPLETE;
1224 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1225 	}
1226 }
1227 
1228 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1229 {
1230 	unsigned long flags;
1231 	int ret;
1232 
1233 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1234 
1235 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1236 	    ctx->ohci->generation == packet->generation) {
1237 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1238 		handle_local_request(ctx, packet);
1239 		return;
1240 	}
1241 
1242 	ret = at_context_queue_packet(ctx, packet);
1243 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1244 
1245 	if (ret < 0)
1246 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1247 
1248 }
1249 
1250 static void bus_reset_tasklet(unsigned long data)
1251 {
1252 	struct fw_ohci *ohci = (struct fw_ohci *)data;
1253 	int self_id_count, i, j, reg;
1254 	int generation, new_generation;
1255 	unsigned long flags;
1256 	void *free_rom = NULL;
1257 	dma_addr_t free_rom_bus = 0;
1258 
1259 	reg = reg_read(ohci, OHCI1394_NodeID);
1260 	if (!(reg & OHCI1394_NodeID_idValid)) {
1261 		fw_notify("node ID not valid, new bus reset in progress\n");
1262 		return;
1263 	}
1264 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1265 		fw_notify("malconfigured bus\n");
1266 		return;
1267 	}
1268 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1269 			       OHCI1394_NodeID_nodeNumber);
1270 
1271 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1272 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1273 		fw_notify("inconsistent self IDs\n");
1274 		return;
1275 	}
1276 	/*
1277 	 * The count in the SelfIDCount register is the number of
1278 	 * bytes in the self ID receive buffer.  Since we also receive
1279 	 * the inverted quadlets and a header quadlet, we shift one
1280 	 * bit extra to get the actual number of self IDs.
1281 	 */
1282 	self_id_count = (reg >> 3) & 0x3ff;
1283 	if (self_id_count == 0) {
1284 		fw_notify("inconsistent self IDs\n");
1285 		return;
1286 	}
1287 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1288 	rmb();
1289 
1290 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1291 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1292 			fw_notify("inconsistent self IDs\n");
1293 			return;
1294 		}
1295 		ohci->self_id_buffer[j] =
1296 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1297 	}
1298 	rmb();
1299 
1300 	/*
1301 	 * Check the consistency of the self IDs we just read.  The
1302 	 * problem we face is that a new bus reset can start while we
1303 	 * read out the self IDs from the DMA buffer. If this happens,
1304 	 * the DMA buffer will be overwritten with new self IDs and we
1305 	 * will read out inconsistent data.  The OHCI specification
1306 	 * (section 11.2) recommends a technique similar to
1307 	 * linux/seqlock.h, where we remember the generation of the
1308 	 * self IDs in the buffer before reading them out and compare
1309 	 * it to the current generation after reading them out.  If
1310 	 * the two generations match we know we have a consistent set
1311 	 * of self IDs.
1312 	 */
1313 
1314 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1315 	if (new_generation != generation) {
1316 		fw_notify("recursive bus reset detected, "
1317 			  "discarding self ids\n");
1318 		return;
1319 	}
1320 
1321 	/* FIXME: Document how the locking works. */
1322 	spin_lock_irqsave(&ohci->lock, flags);
1323 
1324 	ohci->generation = generation;
1325 	context_stop(&ohci->at_request_ctx);
1326 	context_stop(&ohci->at_response_ctx);
1327 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1328 
1329 	if (ohci->bus_reset_packet_quirk)
1330 		ohci->request_generation = generation;
1331 
1332 	/*
1333 	 * This next bit is unrelated to the AT context stuff but we
1334 	 * have to do it under the spinlock also.  If a new config rom
1335 	 * was set up before this reset, the old one is now no longer
1336 	 * in use and we can free it. Update the config rom pointers
1337 	 * to point to the current config rom and clear the
1338 	 * next_config_rom pointer so a new udpate can take place.
1339 	 */
1340 
1341 	if (ohci->next_config_rom != NULL) {
1342 		if (ohci->next_config_rom != ohci->config_rom) {
1343 			free_rom      = ohci->config_rom;
1344 			free_rom_bus  = ohci->config_rom_bus;
1345 		}
1346 		ohci->config_rom      = ohci->next_config_rom;
1347 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1348 		ohci->next_config_rom = NULL;
1349 
1350 		/*
1351 		 * Restore config_rom image and manually update
1352 		 * config_rom registers.  Writing the header quadlet
1353 		 * will indicate that the config rom is ready, so we
1354 		 * do that last.
1355 		 */
1356 		reg_write(ohci, OHCI1394_BusOptions,
1357 			  be32_to_cpu(ohci->config_rom[2]));
1358 		ohci->config_rom[0] = cpu_to_be32(ohci->next_header);
1359 		reg_write(ohci, OHCI1394_ConfigROMhdr, ohci->next_header);
1360 	}
1361 
1362 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1363 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1364 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1365 #endif
1366 
1367 	spin_unlock_irqrestore(&ohci->lock, flags);
1368 
1369 	if (free_rom)
1370 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1371 				  free_rom, free_rom_bus);
1372 
1373 	log_selfids(ohci->node_id, generation,
1374 		    self_id_count, ohci->self_id_buffer);
1375 
1376 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1377 				 self_id_count, ohci->self_id_buffer);
1378 }
1379 
1380 static irqreturn_t irq_handler(int irq, void *data)
1381 {
1382 	struct fw_ohci *ohci = data;
1383 	u32 event, iso_event, cycle_time;
1384 	int i;
1385 
1386 	event = reg_read(ohci, OHCI1394_IntEventClear);
1387 
1388 	if (!event || !~event)
1389 		return IRQ_NONE;
1390 
1391 	/* busReset must not be cleared yet, see OHCI 1.1 clause 7.2.3.2 */
1392 	reg_write(ohci, OHCI1394_IntEventClear, event & ~OHCI1394_busReset);
1393 	log_irqs(event);
1394 
1395 	if (event & OHCI1394_selfIDComplete)
1396 		tasklet_schedule(&ohci->bus_reset_tasklet);
1397 
1398 	if (event & OHCI1394_RQPkt)
1399 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1400 
1401 	if (event & OHCI1394_RSPkt)
1402 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1403 
1404 	if (event & OHCI1394_reqTxComplete)
1405 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
1406 
1407 	if (event & OHCI1394_respTxComplete)
1408 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
1409 
1410 	iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1411 	reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1412 
1413 	while (iso_event) {
1414 		i = ffs(iso_event) - 1;
1415 		tasklet_schedule(&ohci->ir_context_list[i].context.tasklet);
1416 		iso_event &= ~(1 << i);
1417 	}
1418 
1419 	iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1420 	reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1421 
1422 	while (iso_event) {
1423 		i = ffs(iso_event) - 1;
1424 		tasklet_schedule(&ohci->it_context_list[i].context.tasklet);
1425 		iso_event &= ~(1 << i);
1426 	}
1427 
1428 	if (unlikely(event & OHCI1394_regAccessFail))
1429 		fw_error("Register access failure - "
1430 			 "please notify linux1394-devel@lists.sf.net\n");
1431 
1432 	if (unlikely(event & OHCI1394_postedWriteErr))
1433 		fw_error("PCI posted write error\n");
1434 
1435 	if (unlikely(event & OHCI1394_cycleTooLong)) {
1436 		if (printk_ratelimit())
1437 			fw_notify("isochronous cycle too long\n");
1438 		reg_write(ohci, OHCI1394_LinkControlSet,
1439 			  OHCI1394_LinkControl_cycleMaster);
1440 	}
1441 
1442 	if (event & OHCI1394_cycle64Seconds) {
1443 		cycle_time = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1444 		if ((cycle_time & 0x80000000) == 0)
1445 			atomic_inc(&ohci->bus_seconds);
1446 	}
1447 
1448 	return IRQ_HANDLED;
1449 }
1450 
1451 static int software_reset(struct fw_ohci *ohci)
1452 {
1453 	int i;
1454 
1455 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1456 
1457 	for (i = 0; i < OHCI_LOOP_COUNT; i++) {
1458 		if ((reg_read(ohci, OHCI1394_HCControlSet) &
1459 		     OHCI1394_HCControl_softReset) == 0)
1460 			return 0;
1461 		msleep(1);
1462 	}
1463 
1464 	return -EBUSY;
1465 }
1466 
1467 static int ohci_enable(struct fw_card *card, u32 *config_rom, size_t length)
1468 {
1469 	struct fw_ohci *ohci = fw_ohci(card);
1470 	struct pci_dev *dev = to_pci_dev(card->device);
1471 	u32 lps;
1472 	int i;
1473 
1474 	if (software_reset(ohci)) {
1475 		fw_error("Failed to reset ohci card.\n");
1476 		return -EBUSY;
1477 	}
1478 
1479 	/*
1480 	 * Now enable LPS, which we need in order to start accessing
1481 	 * most of the registers.  In fact, on some cards (ALI M5251),
1482 	 * accessing registers in the SClk domain without LPS enabled
1483 	 * will lock up the machine.  Wait 50msec to make sure we have
1484 	 * full link enabled.  However, with some cards (well, at least
1485 	 * a JMicron PCIe card), we have to try again sometimes.
1486 	 */
1487 	reg_write(ohci, OHCI1394_HCControlSet,
1488 		  OHCI1394_HCControl_LPS |
1489 		  OHCI1394_HCControl_postedWriteEnable);
1490 	flush_writes(ohci);
1491 
1492 	for (lps = 0, i = 0; !lps && i < 3; i++) {
1493 		msleep(50);
1494 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
1495 		      OHCI1394_HCControl_LPS;
1496 	}
1497 
1498 	if (!lps) {
1499 		fw_error("Failed to set Link Power Status\n");
1500 		return -EIO;
1501 	}
1502 
1503 	reg_write(ohci, OHCI1394_HCControlClear,
1504 		  OHCI1394_HCControl_noByteSwapData);
1505 
1506 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
1507 	reg_write(ohci, OHCI1394_LinkControlClear,
1508 		  OHCI1394_LinkControl_rcvPhyPkt);
1509 	reg_write(ohci, OHCI1394_LinkControlSet,
1510 		  OHCI1394_LinkControl_rcvSelfID |
1511 		  OHCI1394_LinkControl_cycleTimerEnable |
1512 		  OHCI1394_LinkControl_cycleMaster);
1513 
1514 	reg_write(ohci, OHCI1394_ATRetries,
1515 		  OHCI1394_MAX_AT_REQ_RETRIES |
1516 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
1517 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8));
1518 
1519 	ar_context_run(&ohci->ar_request_ctx);
1520 	ar_context_run(&ohci->ar_response_ctx);
1521 
1522 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
1523 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
1524 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
1525 	reg_write(ohci, OHCI1394_IntMaskSet,
1526 		  OHCI1394_selfIDComplete |
1527 		  OHCI1394_RQPkt | OHCI1394_RSPkt |
1528 		  OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
1529 		  OHCI1394_isochRx | OHCI1394_isochTx |
1530 		  OHCI1394_postedWriteErr | OHCI1394_cycleTooLong |
1531 		  OHCI1394_cycle64Seconds | OHCI1394_regAccessFail |
1532 		  OHCI1394_masterIntEnable);
1533 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
1534 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_busReset);
1535 
1536 	/* Activate link_on bit and contender bit in our self ID packets.*/
1537 	if (ohci_update_phy_reg(card, 4, 0,
1538 				PHY_LINK_ACTIVE | PHY_CONTENDER) < 0)
1539 		return -EIO;
1540 
1541 	/*
1542 	 * When the link is not yet enabled, the atomic config rom
1543 	 * update mechanism described below in ohci_set_config_rom()
1544 	 * is not active.  We have to update ConfigRomHeader and
1545 	 * BusOptions manually, and the write to ConfigROMmap takes
1546 	 * effect immediately.  We tie this to the enabling of the
1547 	 * link, so we have a valid config rom before enabling - the
1548 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
1549 	 * values before enabling.
1550 	 *
1551 	 * However, when the ConfigROMmap is written, some controllers
1552 	 * always read back quadlets 0 and 2 from the config rom to
1553 	 * the ConfigRomHeader and BusOptions registers on bus reset.
1554 	 * They shouldn't do that in this initial case where the link
1555 	 * isn't enabled.  This means we have to use the same
1556 	 * workaround here, setting the bus header to 0 and then write
1557 	 * the right values in the bus reset tasklet.
1558 	 */
1559 
1560 	if (config_rom) {
1561 		ohci->next_config_rom =
1562 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1563 					   &ohci->next_config_rom_bus,
1564 					   GFP_KERNEL);
1565 		if (ohci->next_config_rom == NULL)
1566 			return -ENOMEM;
1567 
1568 		memset(ohci->next_config_rom, 0, CONFIG_ROM_SIZE);
1569 		fw_memcpy_to_be32(ohci->next_config_rom, config_rom, length * 4);
1570 	} else {
1571 		/*
1572 		 * In the suspend case, config_rom is NULL, which
1573 		 * means that we just reuse the old config rom.
1574 		 */
1575 		ohci->next_config_rom = ohci->config_rom;
1576 		ohci->next_config_rom_bus = ohci->config_rom_bus;
1577 	}
1578 
1579 	ohci->next_header = be32_to_cpu(ohci->next_config_rom[0]);
1580 	ohci->next_config_rom[0] = 0;
1581 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
1582 	reg_write(ohci, OHCI1394_BusOptions,
1583 		  be32_to_cpu(ohci->next_config_rom[2]));
1584 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
1585 
1586 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
1587 
1588 	if (request_irq(dev->irq, irq_handler,
1589 			IRQF_SHARED, ohci_driver_name, ohci)) {
1590 		fw_error("Failed to allocate shared interrupt %d.\n",
1591 			 dev->irq);
1592 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1593 				  ohci->config_rom, ohci->config_rom_bus);
1594 		return -EIO;
1595 	}
1596 
1597 	reg_write(ohci, OHCI1394_HCControlSet,
1598 		  OHCI1394_HCControl_linkEnable |
1599 		  OHCI1394_HCControl_BIBimageValid);
1600 	flush_writes(ohci);
1601 
1602 	/*
1603 	 * We are ready to go, initiate bus reset to finish the
1604 	 * initialization.
1605 	 */
1606 
1607 	fw_core_initiate_bus_reset(&ohci->card, 1);
1608 
1609 	return 0;
1610 }
1611 
1612 static int ohci_set_config_rom(struct fw_card *card,
1613 			       u32 *config_rom, size_t length)
1614 {
1615 	struct fw_ohci *ohci;
1616 	unsigned long flags;
1617 	int ret = -EBUSY;
1618 	__be32 *next_config_rom;
1619 	dma_addr_t uninitialized_var(next_config_rom_bus);
1620 
1621 	ohci = fw_ohci(card);
1622 
1623 	/*
1624 	 * When the OHCI controller is enabled, the config rom update
1625 	 * mechanism is a bit tricky, but easy enough to use.  See
1626 	 * section 5.5.6 in the OHCI specification.
1627 	 *
1628 	 * The OHCI controller caches the new config rom address in a
1629 	 * shadow register (ConfigROMmapNext) and needs a bus reset
1630 	 * for the changes to take place.  When the bus reset is
1631 	 * detected, the controller loads the new values for the
1632 	 * ConfigRomHeader and BusOptions registers from the specified
1633 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
1634 	 * shadow register. All automatically and atomically.
1635 	 *
1636 	 * Now, there's a twist to this story.  The automatic load of
1637 	 * ConfigRomHeader and BusOptions doesn't honor the
1638 	 * noByteSwapData bit, so with a be32 config rom, the
1639 	 * controller will load be32 values in to these registers
1640 	 * during the atomic update, even on litte endian
1641 	 * architectures.  The workaround we use is to put a 0 in the
1642 	 * header quadlet; 0 is endian agnostic and means that the
1643 	 * config rom isn't ready yet.  In the bus reset tasklet we
1644 	 * then set up the real values for the two registers.
1645 	 *
1646 	 * We use ohci->lock to avoid racing with the code that sets
1647 	 * ohci->next_config_rom to NULL (see bus_reset_tasklet).
1648 	 */
1649 
1650 	next_config_rom =
1651 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1652 				   &next_config_rom_bus, GFP_KERNEL);
1653 	if (next_config_rom == NULL)
1654 		return -ENOMEM;
1655 
1656 	spin_lock_irqsave(&ohci->lock, flags);
1657 
1658 	if (ohci->next_config_rom == NULL) {
1659 		ohci->next_config_rom = next_config_rom;
1660 		ohci->next_config_rom_bus = next_config_rom_bus;
1661 
1662 		memset(ohci->next_config_rom, 0, CONFIG_ROM_SIZE);
1663 		fw_memcpy_to_be32(ohci->next_config_rom, config_rom,
1664 				  length * 4);
1665 
1666 		ohci->next_header = config_rom[0];
1667 		ohci->next_config_rom[0] = 0;
1668 
1669 		reg_write(ohci, OHCI1394_ConfigROMmap,
1670 			  ohci->next_config_rom_bus);
1671 		ret = 0;
1672 	}
1673 
1674 	spin_unlock_irqrestore(&ohci->lock, flags);
1675 
1676 	/*
1677 	 * Now initiate a bus reset to have the changes take
1678 	 * effect. We clean up the old config rom memory and DMA
1679 	 * mappings in the bus reset tasklet, since the OHCI
1680 	 * controller could need to access it before the bus reset
1681 	 * takes effect.
1682 	 */
1683 	if (ret == 0)
1684 		fw_core_initiate_bus_reset(&ohci->card, 1);
1685 	else
1686 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1687 				  next_config_rom, next_config_rom_bus);
1688 
1689 	return ret;
1690 }
1691 
1692 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
1693 {
1694 	struct fw_ohci *ohci = fw_ohci(card);
1695 
1696 	at_context_transmit(&ohci->at_request_ctx, packet);
1697 }
1698 
1699 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
1700 {
1701 	struct fw_ohci *ohci = fw_ohci(card);
1702 
1703 	at_context_transmit(&ohci->at_response_ctx, packet);
1704 }
1705 
1706 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
1707 {
1708 	struct fw_ohci *ohci = fw_ohci(card);
1709 	struct context *ctx = &ohci->at_request_ctx;
1710 	struct driver_data *driver_data = packet->driver_data;
1711 	int ret = -ENOENT;
1712 
1713 	tasklet_disable(&ctx->tasklet);
1714 
1715 	if (packet->ack != 0)
1716 		goto out;
1717 
1718 	if (packet->payload_bus)
1719 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1720 				 packet->payload_length, DMA_TO_DEVICE);
1721 
1722 	log_ar_at_event('T', packet->speed, packet->header, 0x20);
1723 	driver_data->packet = NULL;
1724 	packet->ack = RCODE_CANCELLED;
1725 	packet->callback(packet, &ohci->card, packet->ack);
1726 	ret = 0;
1727  out:
1728 	tasklet_enable(&ctx->tasklet);
1729 
1730 	return ret;
1731 }
1732 
1733 static int ohci_enable_phys_dma(struct fw_card *card,
1734 				int node_id, int generation)
1735 {
1736 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1737 	return 0;
1738 #else
1739 	struct fw_ohci *ohci = fw_ohci(card);
1740 	unsigned long flags;
1741 	int n, ret = 0;
1742 
1743 	/*
1744 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
1745 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
1746 	 */
1747 
1748 	spin_lock_irqsave(&ohci->lock, flags);
1749 
1750 	if (ohci->generation != generation) {
1751 		ret = -ESTALE;
1752 		goto out;
1753 	}
1754 
1755 	/*
1756 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
1757 	 * enabled for _all_ nodes on remote buses.
1758 	 */
1759 
1760 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
1761 	if (n < 32)
1762 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
1763 	else
1764 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
1765 
1766 	flush_writes(ohci);
1767  out:
1768 	spin_unlock_irqrestore(&ohci->lock, flags);
1769 
1770 	return ret;
1771 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
1772 }
1773 
1774 static u64 ohci_get_bus_time(struct fw_card *card)
1775 {
1776 	struct fw_ohci *ohci = fw_ohci(card);
1777 	u32 cycle_time;
1778 	u64 bus_time;
1779 
1780 	cycle_time = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1781 	bus_time = ((u64)atomic_read(&ohci->bus_seconds) << 32) | cycle_time;
1782 
1783 	return bus_time;
1784 }
1785 
1786 static void copy_iso_headers(struct iso_context *ctx, void *p)
1787 {
1788 	int i = ctx->header_length;
1789 
1790 	if (i + ctx->base.header_size > PAGE_SIZE)
1791 		return;
1792 
1793 	/*
1794 	 * The iso header is byteswapped to little endian by
1795 	 * the controller, but the remaining header quadlets
1796 	 * are big endian.  We want to present all the headers
1797 	 * as big endian, so we have to swap the first quadlet.
1798 	 */
1799 	if (ctx->base.header_size > 0)
1800 		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
1801 	if (ctx->base.header_size > 4)
1802 		*(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
1803 	if (ctx->base.header_size > 8)
1804 		memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
1805 	ctx->header_length += ctx->base.header_size;
1806 }
1807 
1808 static int handle_ir_dualbuffer_packet(struct context *context,
1809 				       struct descriptor *d,
1810 				       struct descriptor *last)
1811 {
1812 	struct iso_context *ctx =
1813 		container_of(context, struct iso_context, context);
1814 	struct db_descriptor *db = (struct db_descriptor *) d;
1815 	__le32 *ir_header;
1816 	size_t header_length;
1817 	void *p, *end;
1818 
1819 	if (db->first_res_count != 0 && db->second_res_count != 0) {
1820 		if (ctx->excess_bytes <= le16_to_cpu(db->second_req_count)) {
1821 			/* This descriptor isn't done yet, stop iteration. */
1822 			return 0;
1823 		}
1824 		ctx->excess_bytes -= le16_to_cpu(db->second_req_count);
1825 	}
1826 
1827 	header_length = le16_to_cpu(db->first_req_count) -
1828 		le16_to_cpu(db->first_res_count);
1829 
1830 	p = db + 1;
1831 	end = p + header_length;
1832 	while (p < end) {
1833 		copy_iso_headers(ctx, p);
1834 		ctx->excess_bytes +=
1835 			(le32_to_cpu(*(__le32 *)(p + 4)) >> 16) & 0xffff;
1836 		p += max(ctx->base.header_size, (size_t)8);
1837 	}
1838 
1839 	ctx->excess_bytes -= le16_to_cpu(db->second_req_count) -
1840 		le16_to_cpu(db->second_res_count);
1841 
1842 	if (le16_to_cpu(db->control) & DESCRIPTOR_IRQ_ALWAYS) {
1843 		ir_header = (__le32 *) (db + 1);
1844 		ctx->base.callback(&ctx->base,
1845 				   le32_to_cpu(ir_header[0]) & 0xffff,
1846 				   ctx->header_length, ctx->header,
1847 				   ctx->base.callback_data);
1848 		ctx->header_length = 0;
1849 	}
1850 
1851 	return 1;
1852 }
1853 
1854 static int handle_ir_packet_per_buffer(struct context *context,
1855 				       struct descriptor *d,
1856 				       struct descriptor *last)
1857 {
1858 	struct iso_context *ctx =
1859 		container_of(context, struct iso_context, context);
1860 	struct descriptor *pd;
1861 	__le32 *ir_header;
1862 	void *p;
1863 
1864 	for (pd = d; pd <= last; pd++) {
1865 		if (pd->transfer_status)
1866 			break;
1867 	}
1868 	if (pd > last)
1869 		/* Descriptor(s) not done yet, stop iteration */
1870 		return 0;
1871 
1872 	p = last + 1;
1873 	copy_iso_headers(ctx, p);
1874 
1875 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
1876 		ir_header = (__le32 *) p;
1877 		ctx->base.callback(&ctx->base,
1878 				   le32_to_cpu(ir_header[0]) & 0xffff,
1879 				   ctx->header_length, ctx->header,
1880 				   ctx->base.callback_data);
1881 		ctx->header_length = 0;
1882 	}
1883 
1884 	return 1;
1885 }
1886 
1887 static int handle_it_packet(struct context *context,
1888 			    struct descriptor *d,
1889 			    struct descriptor *last)
1890 {
1891 	struct iso_context *ctx =
1892 		container_of(context, struct iso_context, context);
1893 
1894 	if (last->transfer_status == 0)
1895 		/* This descriptor isn't done yet, stop iteration. */
1896 		return 0;
1897 
1898 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS)
1899 		ctx->base.callback(&ctx->base, le16_to_cpu(last->res_count),
1900 				   0, NULL, ctx->base.callback_data);
1901 
1902 	return 1;
1903 }
1904 
1905 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
1906 				int type, int channel, size_t header_size)
1907 {
1908 	struct fw_ohci *ohci = fw_ohci(card);
1909 	struct iso_context *ctx, *list;
1910 	descriptor_callback_t callback;
1911 	u64 *channels, dont_care = ~0ULL;
1912 	u32 *mask, regs;
1913 	unsigned long flags;
1914 	int index, ret = -ENOMEM;
1915 
1916 	if (type == FW_ISO_CONTEXT_TRANSMIT) {
1917 		channels = &dont_care;
1918 		mask = &ohci->it_context_mask;
1919 		list = ohci->it_context_list;
1920 		callback = handle_it_packet;
1921 	} else {
1922 		channels = &ohci->ir_context_channels;
1923 		mask = &ohci->ir_context_mask;
1924 		list = ohci->ir_context_list;
1925 		if (ohci->use_dualbuffer)
1926 			callback = handle_ir_dualbuffer_packet;
1927 		else
1928 			callback = handle_ir_packet_per_buffer;
1929 	}
1930 
1931 	spin_lock_irqsave(&ohci->lock, flags);
1932 	index = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
1933 	if (index >= 0) {
1934 		*channels &= ~(1ULL << channel);
1935 		*mask &= ~(1 << index);
1936 	}
1937 	spin_unlock_irqrestore(&ohci->lock, flags);
1938 
1939 	if (index < 0)
1940 		return ERR_PTR(-EBUSY);
1941 
1942 	if (type == FW_ISO_CONTEXT_TRANSMIT)
1943 		regs = OHCI1394_IsoXmitContextBase(index);
1944 	else
1945 		regs = OHCI1394_IsoRcvContextBase(index);
1946 
1947 	ctx = &list[index];
1948 	memset(ctx, 0, sizeof(*ctx));
1949 	ctx->header_length = 0;
1950 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
1951 	if (ctx->header == NULL)
1952 		goto out;
1953 
1954 	ret = context_init(&ctx->context, ohci, regs, callback);
1955 	if (ret < 0)
1956 		goto out_with_header;
1957 
1958 	return &ctx->base;
1959 
1960  out_with_header:
1961 	free_page((unsigned long)ctx->header);
1962  out:
1963 	spin_lock_irqsave(&ohci->lock, flags);
1964 	*mask |= 1 << index;
1965 	spin_unlock_irqrestore(&ohci->lock, flags);
1966 
1967 	return ERR_PTR(ret);
1968 }
1969 
1970 static int ohci_start_iso(struct fw_iso_context *base,
1971 			  s32 cycle, u32 sync, u32 tags)
1972 {
1973 	struct iso_context *ctx = container_of(base, struct iso_context, base);
1974 	struct fw_ohci *ohci = ctx->context.ohci;
1975 	u32 control, match;
1976 	int index;
1977 
1978 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
1979 		index = ctx - ohci->it_context_list;
1980 		match = 0;
1981 		if (cycle >= 0)
1982 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
1983 				(cycle & 0x7fff) << 16;
1984 
1985 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
1986 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
1987 		context_run(&ctx->context, match);
1988 	} else {
1989 		index = ctx - ohci->ir_context_list;
1990 		control = IR_CONTEXT_ISOCH_HEADER;
1991 		if (ohci->use_dualbuffer)
1992 			control |= IR_CONTEXT_DUAL_BUFFER_MODE;
1993 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
1994 		if (cycle >= 0) {
1995 			match |= (cycle & 0x07fff) << 12;
1996 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
1997 		}
1998 
1999 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2000 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2001 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2002 		context_run(&ctx->context, control);
2003 	}
2004 
2005 	return 0;
2006 }
2007 
2008 static int ohci_stop_iso(struct fw_iso_context *base)
2009 {
2010 	struct fw_ohci *ohci = fw_ohci(base->card);
2011 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2012 	int index;
2013 
2014 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2015 		index = ctx - ohci->it_context_list;
2016 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2017 	} else {
2018 		index = ctx - ohci->ir_context_list;
2019 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2020 	}
2021 	flush_writes(ohci);
2022 	context_stop(&ctx->context);
2023 
2024 	return 0;
2025 }
2026 
2027 static void ohci_free_iso_context(struct fw_iso_context *base)
2028 {
2029 	struct fw_ohci *ohci = fw_ohci(base->card);
2030 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2031 	unsigned long flags;
2032 	int index;
2033 
2034 	ohci_stop_iso(base);
2035 	context_release(&ctx->context);
2036 	free_page((unsigned long)ctx->header);
2037 
2038 	spin_lock_irqsave(&ohci->lock, flags);
2039 
2040 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
2041 		index = ctx - ohci->it_context_list;
2042 		ohci->it_context_mask |= 1 << index;
2043 	} else {
2044 		index = ctx - ohci->ir_context_list;
2045 		ohci->ir_context_mask |= 1 << index;
2046 		ohci->ir_context_channels |= 1ULL << base->channel;
2047 	}
2048 
2049 	spin_unlock_irqrestore(&ohci->lock, flags);
2050 }
2051 
2052 static int ohci_queue_iso_transmit(struct fw_iso_context *base,
2053 				   struct fw_iso_packet *packet,
2054 				   struct fw_iso_buffer *buffer,
2055 				   unsigned long payload)
2056 {
2057 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2058 	struct descriptor *d, *last, *pd;
2059 	struct fw_iso_packet *p;
2060 	__le32 *header;
2061 	dma_addr_t d_bus, page_bus;
2062 	u32 z, header_z, payload_z, irq;
2063 	u32 payload_index, payload_end_index, next_page_index;
2064 	int page, end_page, i, length, offset;
2065 
2066 	/*
2067 	 * FIXME: Cycle lost behavior should be configurable: lose
2068 	 * packet, retransmit or terminate..
2069 	 */
2070 
2071 	p = packet;
2072 	payload_index = payload;
2073 
2074 	if (p->skip)
2075 		z = 1;
2076 	else
2077 		z = 2;
2078 	if (p->header_length > 0)
2079 		z++;
2080 
2081 	/* Determine the first page the payload isn't contained in. */
2082 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2083 	if (p->payload_length > 0)
2084 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
2085 	else
2086 		payload_z = 0;
2087 
2088 	z += payload_z;
2089 
2090 	/* Get header size in number of descriptors. */
2091 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2092 
2093 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2094 	if (d == NULL)
2095 		return -ENOMEM;
2096 
2097 	if (!p->skip) {
2098 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2099 		d[0].req_count = cpu_to_le16(8);
2100 
2101 		header = (__le32 *) &d[1];
2102 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2103 					IT_HEADER_TAG(p->tag) |
2104 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2105 					IT_HEADER_CHANNEL(ctx->base.channel) |
2106 					IT_HEADER_SPEED(ctx->base.speed));
2107 		header[1] =
2108 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2109 							  p->payload_length));
2110 	}
2111 
2112 	if (p->header_length > 0) {
2113 		d[2].req_count    = cpu_to_le16(p->header_length);
2114 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2115 		memcpy(&d[z], p->header, p->header_length);
2116 	}
2117 
2118 	pd = d + z - payload_z;
2119 	payload_end_index = payload_index + p->payload_length;
2120 	for (i = 0; i < payload_z; i++) {
2121 		page               = payload_index >> PAGE_SHIFT;
2122 		offset             = payload_index & ~PAGE_MASK;
2123 		next_page_index    = (page + 1) << PAGE_SHIFT;
2124 		length             =
2125 			min(next_page_index, payload_end_index) - payload_index;
2126 		pd[i].req_count    = cpu_to_le16(length);
2127 
2128 		page_bus = page_private(buffer->pages[page]);
2129 		pd[i].data_address = cpu_to_le32(page_bus + offset);
2130 
2131 		payload_index += length;
2132 	}
2133 
2134 	if (p->interrupt)
2135 		irq = DESCRIPTOR_IRQ_ALWAYS;
2136 	else
2137 		irq = DESCRIPTOR_NO_IRQ;
2138 
2139 	last = z == 2 ? d : d + z - 1;
2140 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2141 				     DESCRIPTOR_STATUS |
2142 				     DESCRIPTOR_BRANCH_ALWAYS |
2143 				     irq);
2144 
2145 	context_append(&ctx->context, d, z, header_z);
2146 
2147 	return 0;
2148 }
2149 
2150 static int ohci_queue_iso_receive_dualbuffer(struct fw_iso_context *base,
2151 					     struct fw_iso_packet *packet,
2152 					     struct fw_iso_buffer *buffer,
2153 					     unsigned long payload)
2154 {
2155 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2156 	struct db_descriptor *db = NULL;
2157 	struct descriptor *d;
2158 	struct fw_iso_packet *p;
2159 	dma_addr_t d_bus, page_bus;
2160 	u32 z, header_z, length, rest;
2161 	int page, offset, packet_count, header_size;
2162 
2163 	/*
2164 	 * FIXME: Cycle lost behavior should be configurable: lose
2165 	 * packet, retransmit or terminate..
2166 	 */
2167 
2168 	p = packet;
2169 	z = 2;
2170 
2171 	/*
2172 	 * The OHCI controller puts the isochronous header and trailer in the
2173 	 * buffer, so we need at least 8 bytes.
2174 	 */
2175 	packet_count = p->header_length / ctx->base.header_size;
2176 	header_size = packet_count * max(ctx->base.header_size, (size_t)8);
2177 
2178 	/* Get header size in number of descriptors. */
2179 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2180 	page     = payload >> PAGE_SHIFT;
2181 	offset   = payload & ~PAGE_MASK;
2182 	rest     = p->payload_length;
2183 
2184 	/* FIXME: make packet-per-buffer/dual-buffer a context option */
2185 	while (rest > 0) {
2186 		d = context_get_descriptors(&ctx->context,
2187 					    z + header_z, &d_bus);
2188 		if (d == NULL)
2189 			return -ENOMEM;
2190 
2191 		db = (struct db_descriptor *) d;
2192 		db->control = cpu_to_le16(DESCRIPTOR_STATUS |
2193 					  DESCRIPTOR_BRANCH_ALWAYS);
2194 		db->first_size =
2195 		    cpu_to_le16(max(ctx->base.header_size, (size_t)8));
2196 		if (p->skip && rest == p->payload_length) {
2197 			db->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2198 			db->first_req_count = db->first_size;
2199 		} else {
2200 			db->first_req_count = cpu_to_le16(header_size);
2201 		}
2202 		db->first_res_count = db->first_req_count;
2203 		db->first_buffer = cpu_to_le32(d_bus + sizeof(*db));
2204 
2205 		if (p->skip && rest == p->payload_length)
2206 			length = 4;
2207 		else if (offset + rest < PAGE_SIZE)
2208 			length = rest;
2209 		else
2210 			length = PAGE_SIZE - offset;
2211 
2212 		db->second_req_count = cpu_to_le16(length);
2213 		db->second_res_count = db->second_req_count;
2214 		page_bus = page_private(buffer->pages[page]);
2215 		db->second_buffer = cpu_to_le32(page_bus + offset);
2216 
2217 		if (p->interrupt && length == rest)
2218 			db->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2219 
2220 		context_append(&ctx->context, d, z, header_z);
2221 		offset = (offset + length) & ~PAGE_MASK;
2222 		rest -= length;
2223 		if (offset == 0)
2224 			page++;
2225 	}
2226 
2227 	return 0;
2228 }
2229 
2230 static int ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base,
2231 					struct fw_iso_packet *packet,
2232 					struct fw_iso_buffer *buffer,
2233 					unsigned long payload)
2234 {
2235 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2236 	struct descriptor *d = NULL, *pd = NULL;
2237 	struct fw_iso_packet *p = packet;
2238 	dma_addr_t d_bus, page_bus;
2239 	u32 z, header_z, rest;
2240 	int i, j, length;
2241 	int page, offset, packet_count, header_size, payload_per_buffer;
2242 
2243 	/*
2244 	 * The OHCI controller puts the isochronous header and trailer in the
2245 	 * buffer, so we need at least 8 bytes.
2246 	 */
2247 	packet_count = p->header_length / ctx->base.header_size;
2248 	header_size  = max(ctx->base.header_size, (size_t)8);
2249 
2250 	/* Get header size in number of descriptors. */
2251 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2252 	page     = payload >> PAGE_SHIFT;
2253 	offset   = payload & ~PAGE_MASK;
2254 	payload_per_buffer = p->payload_length / packet_count;
2255 
2256 	for (i = 0; i < packet_count; i++) {
2257 		/* d points to the header descriptor */
2258 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
2259 		d = context_get_descriptors(&ctx->context,
2260 				z + header_z, &d_bus);
2261 		if (d == NULL)
2262 			return -ENOMEM;
2263 
2264 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
2265 					      DESCRIPTOR_INPUT_MORE);
2266 		if (p->skip && i == 0)
2267 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2268 		d->req_count    = cpu_to_le16(header_size);
2269 		d->res_count    = d->req_count;
2270 		d->transfer_status = 0;
2271 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
2272 
2273 		rest = payload_per_buffer;
2274 		for (j = 1; j < z; j++) {
2275 			pd = d + j;
2276 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2277 						  DESCRIPTOR_INPUT_MORE);
2278 
2279 			if (offset + rest < PAGE_SIZE)
2280 				length = rest;
2281 			else
2282 				length = PAGE_SIZE - offset;
2283 			pd->req_count = cpu_to_le16(length);
2284 			pd->res_count = pd->req_count;
2285 			pd->transfer_status = 0;
2286 
2287 			page_bus = page_private(buffer->pages[page]);
2288 			pd->data_address = cpu_to_le32(page_bus + offset);
2289 
2290 			offset = (offset + length) & ~PAGE_MASK;
2291 			rest -= length;
2292 			if (offset == 0)
2293 				page++;
2294 		}
2295 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2296 					  DESCRIPTOR_INPUT_LAST |
2297 					  DESCRIPTOR_BRANCH_ALWAYS);
2298 		if (p->interrupt && i == packet_count - 1)
2299 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2300 
2301 		context_append(&ctx->context, d, z, header_z);
2302 	}
2303 
2304 	return 0;
2305 }
2306 
2307 static int ohci_queue_iso(struct fw_iso_context *base,
2308 			  struct fw_iso_packet *packet,
2309 			  struct fw_iso_buffer *buffer,
2310 			  unsigned long payload)
2311 {
2312 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2313 	unsigned long flags;
2314 	int ret;
2315 
2316 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
2317 	if (base->type == FW_ISO_CONTEXT_TRANSMIT)
2318 		ret = ohci_queue_iso_transmit(base, packet, buffer, payload);
2319 	else if (ctx->context.ohci->use_dualbuffer)
2320 		ret = ohci_queue_iso_receive_dualbuffer(base, packet,
2321 							buffer, payload);
2322 	else
2323 		ret = ohci_queue_iso_receive_packet_per_buffer(base, packet,
2324 							buffer, payload);
2325 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
2326 
2327 	return ret;
2328 }
2329 
2330 static const struct fw_card_driver ohci_driver = {
2331 	.enable			= ohci_enable,
2332 	.update_phy_reg		= ohci_update_phy_reg,
2333 	.set_config_rom		= ohci_set_config_rom,
2334 	.send_request		= ohci_send_request,
2335 	.send_response		= ohci_send_response,
2336 	.cancel_packet		= ohci_cancel_packet,
2337 	.enable_phys_dma	= ohci_enable_phys_dma,
2338 	.get_bus_time		= ohci_get_bus_time,
2339 
2340 	.allocate_iso_context	= ohci_allocate_iso_context,
2341 	.free_iso_context	= ohci_free_iso_context,
2342 	.queue_iso		= ohci_queue_iso,
2343 	.start_iso		= ohci_start_iso,
2344 	.stop_iso		= ohci_stop_iso,
2345 };
2346 
2347 #ifdef CONFIG_PPC_PMAC
2348 static void ohci_pmac_on(struct pci_dev *dev)
2349 {
2350 	if (machine_is(powermac)) {
2351 		struct device_node *ofn = pci_device_to_OF_node(dev);
2352 
2353 		if (ofn) {
2354 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
2355 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
2356 		}
2357 	}
2358 }
2359 
2360 static void ohci_pmac_off(struct pci_dev *dev)
2361 {
2362 	if (machine_is(powermac)) {
2363 		struct device_node *ofn = pci_device_to_OF_node(dev);
2364 
2365 		if (ofn) {
2366 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
2367 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
2368 		}
2369 	}
2370 }
2371 #else
2372 #define ohci_pmac_on(dev)
2373 #define ohci_pmac_off(dev)
2374 #endif /* CONFIG_PPC_PMAC */
2375 
2376 #define PCI_VENDOR_ID_AGERE		PCI_VENDOR_ID_ATT
2377 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
2378 
2379 static int __devinit pci_probe(struct pci_dev *dev,
2380 			       const struct pci_device_id *ent)
2381 {
2382 	struct fw_ohci *ohci;
2383 	u32 bus_options, max_receive, link_speed, version;
2384 	u64 guid;
2385 	int err;
2386 	size_t size;
2387 
2388 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
2389 	if (ohci == NULL) {
2390 		err = -ENOMEM;
2391 		goto fail;
2392 	}
2393 
2394 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
2395 
2396 	ohci_pmac_on(dev);
2397 
2398 	err = pci_enable_device(dev);
2399 	if (err) {
2400 		fw_error("Failed to enable OHCI hardware\n");
2401 		goto fail_free;
2402 	}
2403 
2404 	pci_set_master(dev);
2405 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
2406 	pci_set_drvdata(dev, ohci);
2407 
2408 	spin_lock_init(&ohci->lock);
2409 
2410 	tasklet_init(&ohci->bus_reset_tasklet,
2411 		     bus_reset_tasklet, (unsigned long)ohci);
2412 
2413 	err = pci_request_region(dev, 0, ohci_driver_name);
2414 	if (err) {
2415 		fw_error("MMIO resource unavailable\n");
2416 		goto fail_disable;
2417 	}
2418 
2419 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
2420 	if (ohci->registers == NULL) {
2421 		fw_error("Failed to remap registers\n");
2422 		err = -ENXIO;
2423 		goto fail_iomem;
2424 	}
2425 
2426 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2427 	ohci->use_dualbuffer = version >= OHCI_VERSION_1_1;
2428 
2429 	/* dual-buffer mode is broken if more than one IR context is active */
2430 	if (dev->vendor == PCI_VENDOR_ID_AGERE &&
2431 	    dev->device == PCI_DEVICE_ID_AGERE_FW643)
2432 		ohci->use_dualbuffer = false;
2433 
2434 	/* dual-buffer mode is broken */
2435 	if (dev->vendor == PCI_VENDOR_ID_RICOH &&
2436 	    dev->device == PCI_DEVICE_ID_RICOH_R5C832)
2437 		ohci->use_dualbuffer = false;
2438 
2439 /* x86-32 currently doesn't use highmem for dma_alloc_coherent */
2440 #if !defined(CONFIG_X86_32)
2441 	/* dual-buffer mode is broken with descriptor addresses above 2G */
2442 	if (dev->vendor == PCI_VENDOR_ID_TI &&
2443 	    dev->device == PCI_DEVICE_ID_TI_TSB43AB22)
2444 		ohci->use_dualbuffer = false;
2445 #endif
2446 
2447 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
2448 	ohci->old_uninorth = dev->vendor == PCI_VENDOR_ID_APPLE &&
2449 			     dev->device == PCI_DEVICE_ID_APPLE_UNI_N_FW;
2450 #endif
2451 	ohci->bus_reset_packet_quirk = dev->vendor == PCI_VENDOR_ID_TI;
2452 
2453 	ar_context_init(&ohci->ar_request_ctx, ohci,
2454 			OHCI1394_AsReqRcvContextControlSet);
2455 
2456 	ar_context_init(&ohci->ar_response_ctx, ohci,
2457 			OHCI1394_AsRspRcvContextControlSet);
2458 
2459 	context_init(&ohci->at_request_ctx, ohci,
2460 		     OHCI1394_AsReqTrContextControlSet, handle_at_packet);
2461 
2462 	context_init(&ohci->at_response_ctx, ohci,
2463 		     OHCI1394_AsRspTrContextControlSet, handle_at_packet);
2464 
2465 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
2466 	ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
2467 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
2468 	size = sizeof(struct iso_context) * hweight32(ohci->it_context_mask);
2469 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
2470 
2471 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
2472 	ohci->ir_context_channels = ~0ULL;
2473 	ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
2474 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
2475 	size = sizeof(struct iso_context) * hweight32(ohci->ir_context_mask);
2476 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
2477 
2478 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
2479 		err = -ENOMEM;
2480 		goto fail_contexts;
2481 	}
2482 
2483 	/* self-id dma buffer allocation */
2484 	ohci->self_id_cpu = dma_alloc_coherent(ohci->card.device,
2485 					       SELF_ID_BUF_SIZE,
2486 					       &ohci->self_id_bus,
2487 					       GFP_KERNEL);
2488 	if (ohci->self_id_cpu == NULL) {
2489 		err = -ENOMEM;
2490 		goto fail_contexts;
2491 	}
2492 
2493 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
2494 	max_receive = (bus_options >> 12) & 0xf;
2495 	link_speed = bus_options & 0x7;
2496 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
2497 		reg_read(ohci, OHCI1394_GUIDLo);
2498 
2499 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
2500 	if (err)
2501 		goto fail_self_id;
2502 
2503 	fw_notify("Added fw-ohci device %s, OHCI version %x.%x\n",
2504 		  dev_name(&dev->dev), version >> 16, version & 0xff);
2505 
2506 	return 0;
2507 
2508  fail_self_id:
2509 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2510 			  ohci->self_id_cpu, ohci->self_id_bus);
2511  fail_contexts:
2512 	kfree(ohci->ir_context_list);
2513 	kfree(ohci->it_context_list);
2514 	context_release(&ohci->at_response_ctx);
2515 	context_release(&ohci->at_request_ctx);
2516 	ar_context_release(&ohci->ar_response_ctx);
2517 	ar_context_release(&ohci->ar_request_ctx);
2518 	pci_iounmap(dev, ohci->registers);
2519  fail_iomem:
2520 	pci_release_region(dev, 0);
2521  fail_disable:
2522 	pci_disable_device(dev);
2523  fail_free:
2524 	kfree(&ohci->card);
2525 	ohci_pmac_off(dev);
2526  fail:
2527 	if (err == -ENOMEM)
2528 		fw_error("Out of memory\n");
2529 
2530 	return err;
2531 }
2532 
2533 static void pci_remove(struct pci_dev *dev)
2534 {
2535 	struct fw_ohci *ohci;
2536 
2537 	ohci = pci_get_drvdata(dev);
2538 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2539 	flush_writes(ohci);
2540 	fw_core_remove_card(&ohci->card);
2541 
2542 	/*
2543 	 * FIXME: Fail all pending packets here, now that the upper
2544 	 * layers can't queue any more.
2545 	 */
2546 
2547 	software_reset(ohci);
2548 	free_irq(dev->irq, ohci);
2549 
2550 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
2551 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2552 				  ohci->next_config_rom, ohci->next_config_rom_bus);
2553 	if (ohci->config_rom)
2554 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2555 				  ohci->config_rom, ohci->config_rom_bus);
2556 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2557 			  ohci->self_id_cpu, ohci->self_id_bus);
2558 	ar_context_release(&ohci->ar_request_ctx);
2559 	ar_context_release(&ohci->ar_response_ctx);
2560 	context_release(&ohci->at_request_ctx);
2561 	context_release(&ohci->at_response_ctx);
2562 	kfree(ohci->it_context_list);
2563 	kfree(ohci->ir_context_list);
2564 	pci_iounmap(dev, ohci->registers);
2565 	pci_release_region(dev, 0);
2566 	pci_disable_device(dev);
2567 	kfree(&ohci->card);
2568 	ohci_pmac_off(dev);
2569 
2570 	fw_notify("Removed fw-ohci device.\n");
2571 }
2572 
2573 #ifdef CONFIG_PM
2574 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
2575 {
2576 	struct fw_ohci *ohci = pci_get_drvdata(dev);
2577 	int err;
2578 
2579 	software_reset(ohci);
2580 	free_irq(dev->irq, ohci);
2581 	err = pci_save_state(dev);
2582 	if (err) {
2583 		fw_error("pci_save_state failed\n");
2584 		return err;
2585 	}
2586 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
2587 	if (err)
2588 		fw_error("pci_set_power_state failed with %d\n", err);
2589 	ohci_pmac_off(dev);
2590 
2591 	return 0;
2592 }
2593 
2594 static int pci_resume(struct pci_dev *dev)
2595 {
2596 	struct fw_ohci *ohci = pci_get_drvdata(dev);
2597 	int err;
2598 
2599 	ohci_pmac_on(dev);
2600 	pci_set_power_state(dev, PCI_D0);
2601 	pci_restore_state(dev);
2602 	err = pci_enable_device(dev);
2603 	if (err) {
2604 		fw_error("pci_enable_device failed\n");
2605 		return err;
2606 	}
2607 
2608 	return ohci_enable(&ohci->card, NULL, 0);
2609 }
2610 #endif
2611 
2612 static struct pci_device_id pci_table[] = {
2613 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
2614 	{ }
2615 };
2616 
2617 MODULE_DEVICE_TABLE(pci, pci_table);
2618 
2619 static struct pci_driver fw_ohci_pci_driver = {
2620 	.name		= ohci_driver_name,
2621 	.id_table	= pci_table,
2622 	.probe		= pci_probe,
2623 	.remove		= pci_remove,
2624 #ifdef CONFIG_PM
2625 	.resume		= pci_resume,
2626 	.suspend	= pci_suspend,
2627 #endif
2628 };
2629 
2630 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
2631 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
2632 MODULE_LICENSE("GPL");
2633 
2634 /* Provide a module alias so root-on-sbp2 initrds don't break. */
2635 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
2636 MODULE_ALIAS("ohci1394");
2637 #endif
2638 
2639 static int __init fw_ohci_init(void)
2640 {
2641 	return pci_register_driver(&fw_ohci_pci_driver);
2642 }
2643 
2644 static void __exit fw_ohci_cleanup(void)
2645 {
2646 	pci_unregister_driver(&fw_ohci_pci_driver);
2647 }
2648 
2649 module_init(fw_ohci_init);
2650 module_exit(fw_ohci_cleanup);
2651