xref: /linux/drivers/firewire/ohci.c (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
1 /*
2  * Driver for OHCI 1394 controllers
3  *
4  * Copyright (C) 2003-2006 Kristian Hoegsberg <krh@bitplanet.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20 
21 #include <linux/bitops.h>
22 #include <linux/bug.h>
23 #include <linux/compiler.h>
24 #include <linux/delay.h>
25 #include <linux/device.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/firewire.h>
28 #include <linux/firewire-constants.h>
29 #include <linux/init.h>
30 #include <linux/interrupt.h>
31 #include <linux/io.h>
32 #include <linux/kernel.h>
33 #include <linux/list.h>
34 #include <linux/mm.h>
35 #include <linux/module.h>
36 #include <linux/moduleparam.h>
37 #include <linux/mutex.h>
38 #include <linux/pci.h>
39 #include <linux/pci_ids.h>
40 #include <linux/slab.h>
41 #include <linux/spinlock.h>
42 #include <linux/string.h>
43 #include <linux/time.h>
44 #include <linux/vmalloc.h>
45 #include <linux/workqueue.h>
46 
47 #include <asm/byteorder.h>
48 #include <asm/page.h>
49 
50 #ifdef CONFIG_PPC_PMAC
51 #include <asm/pmac_feature.h>
52 #endif
53 
54 #include "core.h"
55 #include "ohci.h"
56 
57 #define DESCRIPTOR_OUTPUT_MORE		0
58 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
59 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
60 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
61 #define DESCRIPTOR_STATUS		(1 << 11)
62 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
63 #define DESCRIPTOR_PING			(1 << 7)
64 #define DESCRIPTOR_YY			(1 << 6)
65 #define DESCRIPTOR_NO_IRQ		(0 << 4)
66 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
67 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
68 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
69 #define DESCRIPTOR_WAIT			(3 << 0)
70 
71 struct descriptor {
72 	__le16 req_count;
73 	__le16 control;
74 	__le32 data_address;
75 	__le32 branch_address;
76 	__le16 res_count;
77 	__le16 transfer_status;
78 } __attribute__((aligned(16)));
79 
80 #define CONTROL_SET(regs)	(regs)
81 #define CONTROL_CLEAR(regs)	((regs) + 4)
82 #define COMMAND_PTR(regs)	((regs) + 12)
83 #define CONTEXT_MATCH(regs)	((regs) + 16)
84 
85 #define AR_BUFFER_SIZE	(32*1024)
86 #define AR_BUFFERS_MIN	DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
87 /* we need at least two pages for proper list management */
88 #define AR_BUFFERS	(AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)
89 
90 #define MAX_ASYNC_PAYLOAD	4096
91 #define MAX_AR_PACKET_SIZE	(16 + MAX_ASYNC_PAYLOAD + 4)
92 #define AR_WRAPAROUND_PAGES	DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)
93 
94 struct ar_context {
95 	struct fw_ohci *ohci;
96 	struct page *pages[AR_BUFFERS];
97 	void *buffer;
98 	struct descriptor *descriptors;
99 	dma_addr_t descriptors_bus;
100 	void *pointer;
101 	unsigned int last_buffer_index;
102 	u32 regs;
103 	struct tasklet_struct tasklet;
104 };
105 
106 struct context;
107 
108 typedef int (*descriptor_callback_t)(struct context *ctx,
109 				     struct descriptor *d,
110 				     struct descriptor *last);
111 
112 /*
113  * A buffer that contains a block of DMA-able coherent memory used for
114  * storing a portion of a DMA descriptor program.
115  */
116 struct descriptor_buffer {
117 	struct list_head list;
118 	dma_addr_t buffer_bus;
119 	size_t buffer_size;
120 	size_t used;
121 	struct descriptor buffer[0];
122 };
123 
124 struct context {
125 	struct fw_ohci *ohci;
126 	u32 regs;
127 	int total_allocation;
128 	u32 current_bus;
129 	bool running;
130 	bool flushing;
131 
132 	/*
133 	 * List of page-sized buffers for storing DMA descriptors.
134 	 * Head of list contains buffers in use and tail of list contains
135 	 * free buffers.
136 	 */
137 	struct list_head buffer_list;
138 
139 	/*
140 	 * Pointer to a buffer inside buffer_list that contains the tail
141 	 * end of the current DMA program.
142 	 */
143 	struct descriptor_buffer *buffer_tail;
144 
145 	/*
146 	 * The descriptor containing the branch address of the first
147 	 * descriptor that has not yet been filled by the device.
148 	 */
149 	struct descriptor *last;
150 
151 	/*
152 	 * The last descriptor in the DMA program.  It contains the branch
153 	 * address that must be updated upon appending a new descriptor.
154 	 */
155 	struct descriptor *prev;
156 
157 	descriptor_callback_t callback;
158 
159 	struct tasklet_struct tasklet;
160 };
161 
162 #define IT_HEADER_SY(v)          ((v) <<  0)
163 #define IT_HEADER_TCODE(v)       ((v) <<  4)
164 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
165 #define IT_HEADER_TAG(v)         ((v) << 14)
166 #define IT_HEADER_SPEED(v)       ((v) << 16)
167 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
168 
169 struct iso_context {
170 	struct fw_iso_context base;
171 	struct context context;
172 	void *header;
173 	size_t header_length;
174 	unsigned long flushing_completions;
175 	u32 mc_buffer_bus;
176 	u16 mc_completed;
177 	u16 last_timestamp;
178 	u8 sync;
179 	u8 tags;
180 };
181 
182 #define CONFIG_ROM_SIZE 1024
183 
184 struct fw_ohci {
185 	struct fw_card card;
186 
187 	__iomem char *registers;
188 	int node_id;
189 	int generation;
190 	int request_generation;	/* for timestamping incoming requests */
191 	unsigned quirks;
192 	unsigned int pri_req_max;
193 	u32 bus_time;
194 	bool is_root;
195 	bool csr_state_setclear_abdicate;
196 	int n_ir;
197 	int n_it;
198 	/*
199 	 * Spinlock for accessing fw_ohci data.  Never call out of
200 	 * this driver with this lock held.
201 	 */
202 	spinlock_t lock;
203 
204 	struct mutex phy_reg_mutex;
205 
206 	void *misc_buffer;
207 	dma_addr_t misc_buffer_bus;
208 
209 	struct ar_context ar_request_ctx;
210 	struct ar_context ar_response_ctx;
211 	struct context at_request_ctx;
212 	struct context at_response_ctx;
213 
214 	u32 it_context_support;
215 	u32 it_context_mask;     /* unoccupied IT contexts */
216 	struct iso_context *it_context_list;
217 	u64 ir_context_channels; /* unoccupied channels */
218 	u32 ir_context_support;
219 	u32 ir_context_mask;     /* unoccupied IR contexts */
220 	struct iso_context *ir_context_list;
221 	u64 mc_channels; /* channels in use by the multichannel IR context */
222 	bool mc_allocated;
223 
224 	__be32    *config_rom;
225 	dma_addr_t config_rom_bus;
226 	__be32    *next_config_rom;
227 	dma_addr_t next_config_rom_bus;
228 	__be32     next_header;
229 
230 	__le32    *self_id_cpu;
231 	dma_addr_t self_id_bus;
232 	struct work_struct bus_reset_work;
233 
234 	u32 self_id_buffer[512];
235 };
236 
237 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
238 {
239 	return container_of(card, struct fw_ohci, card);
240 }
241 
242 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
243 #define IR_CONTEXT_BUFFER_FILL		0x80000000
244 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
245 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
246 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
247 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
248 
249 #define CONTEXT_RUN	0x8000
250 #define CONTEXT_WAKE	0x1000
251 #define CONTEXT_DEAD	0x0800
252 #define CONTEXT_ACTIVE	0x0400
253 
254 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
255 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
256 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
257 
258 #define OHCI1394_REGISTER_SIZE		0x800
259 #define OHCI1394_PCI_HCI_Control	0x40
260 #define SELF_ID_BUF_SIZE		0x800
261 #define OHCI_TCODE_PHY_PACKET		0x0e
262 #define OHCI_VERSION_1_1		0x010010
263 
264 static char ohci_driver_name[] = KBUILD_MODNAME;
265 
266 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
267 #define PCI_DEVICE_ID_CREATIVE_SB1394	0x4001
268 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
269 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
270 #define PCI_DEVICE_ID_TI_TSB12LV26	0x8020
271 #define PCI_DEVICE_ID_TI_TSB82AA2	0x8025
272 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
273 
274 #define QUIRK_CYCLE_TIMER		1
275 #define QUIRK_RESET_PACKET		2
276 #define QUIRK_BE_HEADERS		4
277 #define QUIRK_NO_1394A			8
278 #define QUIRK_NO_MSI			16
279 #define QUIRK_TI_SLLZ059		32
280 
281 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
282 static const struct {
283 	unsigned short vendor, device, revision, flags;
284 } ohci_quirks[] = {
285 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
286 		QUIRK_CYCLE_TIMER},
287 
288 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
289 		QUIRK_BE_HEADERS},
290 
291 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
292 		QUIRK_NO_MSI},
293 
294 	{PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
295 		QUIRK_RESET_PACKET},
296 
297 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
298 		QUIRK_NO_MSI},
299 
300 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
301 		QUIRK_CYCLE_TIMER},
302 
303 	{PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
304 		QUIRK_NO_MSI},
305 
306 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
307 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
308 
309 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
310 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
311 
312 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
313 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
314 
315 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
316 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
317 
318 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
319 		QUIRK_RESET_PACKET},
320 
321 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
322 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
323 };
324 
325 /* This overrides anything that was found in ohci_quirks[]. */
326 static int param_quirks;
327 module_param_named(quirks, param_quirks, int, 0644);
328 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
329 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
330 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
331 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
332 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
333 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
334 	", TI SLLZ059 erratum = "	__stringify(QUIRK_TI_SLLZ059)
335 	")");
336 
337 #define OHCI_PARAM_DEBUG_AT_AR		1
338 #define OHCI_PARAM_DEBUG_SELFIDS	2
339 #define OHCI_PARAM_DEBUG_IRQS		4
340 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
341 
342 static int param_debug;
343 module_param_named(debug, param_debug, int, 0644);
344 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
345 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
346 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
347 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
348 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
349 	", or a combination, or all = -1)");
350 
351 static void log_irqs(struct fw_ohci *ohci, u32 evt)
352 {
353 	if (likely(!(param_debug &
354 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
355 		return;
356 
357 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
358 	    !(evt & OHCI1394_busReset))
359 		return;
360 
361 	dev_notice(ohci->card.device,
362 	    "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
363 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
364 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
365 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
366 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
367 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
368 	    evt & OHCI1394_isochRx		? " IR"			: "",
369 	    evt & OHCI1394_isochTx		? " IT"			: "",
370 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
371 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
372 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
373 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
374 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
375 	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
376 	    evt & OHCI1394_busReset		? " busReset"		: "",
377 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
378 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
379 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
380 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
381 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
382 		    OHCI1394_cycleInconsistent |
383 		    OHCI1394_regAccessFail | OHCI1394_busReset)
384 						? " ?"			: "");
385 }
386 
387 static const char *speed[] = {
388 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
389 };
390 static const char *power[] = {
391 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
392 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
393 };
394 static const char port[] = { '.', '-', 'p', 'c', };
395 
396 static char _p(u32 *s, int shift)
397 {
398 	return port[*s >> shift & 3];
399 }
400 
401 static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
402 {
403 	u32 *s;
404 
405 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
406 		return;
407 
408 	dev_notice(ohci->card.device,
409 		   "%d selfIDs, generation %d, local node ID %04x\n",
410 		   self_id_count, generation, ohci->node_id);
411 
412 	for (s = ohci->self_id_buffer; self_id_count--; ++s)
413 		if ((*s & 1 << 23) == 0)
414 			dev_notice(ohci->card.device,
415 			    "selfID 0: %08x, phy %d [%c%c%c] "
416 			    "%s gc=%d %s %s%s%s\n",
417 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
418 			    speed[*s >> 14 & 3], *s >> 16 & 63,
419 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
420 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
421 		else
422 			dev_notice(ohci->card.device,
423 			    "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
424 			    *s, *s >> 24 & 63,
425 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
426 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
427 }
428 
429 static const char *evts[] = {
430 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
431 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
432 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
433 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
434 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
435 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
436 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
437 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
438 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
439 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
440 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
441 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
442 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
443 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
444 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
445 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
446 	[0x20] = "pending/cancelled",
447 };
448 static const char *tcodes[] = {
449 	[0x0] = "QW req",		[0x1] = "BW req",
450 	[0x2] = "W resp",		[0x3] = "-reserved-",
451 	[0x4] = "QR req",		[0x5] = "BR req",
452 	[0x6] = "QR resp",		[0x7] = "BR resp",
453 	[0x8] = "cycle start",		[0x9] = "Lk req",
454 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
455 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
456 	[0xe] = "link internal",	[0xf] = "-reserved-",
457 };
458 
459 static void log_ar_at_event(struct fw_ohci *ohci,
460 			    char dir, int speed, u32 *header, int evt)
461 {
462 	int tcode = header[0] >> 4 & 0xf;
463 	char specific[12];
464 
465 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
466 		return;
467 
468 	if (unlikely(evt >= ARRAY_SIZE(evts)))
469 			evt = 0x1f;
470 
471 	if (evt == OHCI1394_evt_bus_reset) {
472 		dev_notice(ohci->card.device,
473 			   "A%c evt_bus_reset, generation %d\n",
474 			   dir, (header[2] >> 16) & 0xff);
475 		return;
476 	}
477 
478 	switch (tcode) {
479 	case 0x0: case 0x6: case 0x8:
480 		snprintf(specific, sizeof(specific), " = %08x",
481 			 be32_to_cpu((__force __be32)header[3]));
482 		break;
483 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
484 		snprintf(specific, sizeof(specific), " %x,%x",
485 			 header[3] >> 16, header[3] & 0xffff);
486 		break;
487 	default:
488 		specific[0] = '\0';
489 	}
490 
491 	switch (tcode) {
492 	case 0xa:
493 		dev_notice(ohci->card.device,
494 			   "A%c %s, %s\n",
495 			   dir, evts[evt], tcodes[tcode]);
496 		break;
497 	case 0xe:
498 		dev_notice(ohci->card.device,
499 			   "A%c %s, PHY %08x %08x\n",
500 			   dir, evts[evt], header[1], header[2]);
501 		break;
502 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
503 		dev_notice(ohci->card.device,
504 			   "A%c spd %x tl %02x, "
505 			   "%04x -> %04x, %s, "
506 			   "%s, %04x%08x%s\n",
507 			   dir, speed, header[0] >> 10 & 0x3f,
508 			   header[1] >> 16, header[0] >> 16, evts[evt],
509 			   tcodes[tcode], header[1] & 0xffff, header[2], specific);
510 		break;
511 	default:
512 		dev_notice(ohci->card.device,
513 			   "A%c spd %x tl %02x, "
514 			   "%04x -> %04x, %s, "
515 			   "%s%s\n",
516 			   dir, speed, header[0] >> 10 & 0x3f,
517 			   header[1] >> 16, header[0] >> 16, evts[evt],
518 			   tcodes[tcode], specific);
519 	}
520 }
521 
522 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
523 {
524 	writel(data, ohci->registers + offset);
525 }
526 
527 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
528 {
529 	return readl(ohci->registers + offset);
530 }
531 
532 static inline void flush_writes(const struct fw_ohci *ohci)
533 {
534 	/* Do a dummy read to flush writes. */
535 	reg_read(ohci, OHCI1394_Version);
536 }
537 
538 /*
539  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
540  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
541  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
542  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
543  */
544 static int read_phy_reg(struct fw_ohci *ohci, int addr)
545 {
546 	u32 val;
547 	int i;
548 
549 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
550 	for (i = 0; i < 3 + 100; i++) {
551 		val = reg_read(ohci, OHCI1394_PhyControl);
552 		if (!~val)
553 			return -ENODEV; /* Card was ejected. */
554 
555 		if (val & OHCI1394_PhyControl_ReadDone)
556 			return OHCI1394_PhyControl_ReadData(val);
557 
558 		/*
559 		 * Try a few times without waiting.  Sleeping is necessary
560 		 * only when the link/PHY interface is busy.
561 		 */
562 		if (i >= 3)
563 			msleep(1);
564 	}
565 	dev_err(ohci->card.device, "failed to read phy reg\n");
566 
567 	return -EBUSY;
568 }
569 
570 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
571 {
572 	int i;
573 
574 	reg_write(ohci, OHCI1394_PhyControl,
575 		  OHCI1394_PhyControl_Write(addr, val));
576 	for (i = 0; i < 3 + 100; i++) {
577 		val = reg_read(ohci, OHCI1394_PhyControl);
578 		if (!~val)
579 			return -ENODEV; /* Card was ejected. */
580 
581 		if (!(val & OHCI1394_PhyControl_WritePending))
582 			return 0;
583 
584 		if (i >= 3)
585 			msleep(1);
586 	}
587 	dev_err(ohci->card.device, "failed to write phy reg\n");
588 
589 	return -EBUSY;
590 }
591 
592 static int update_phy_reg(struct fw_ohci *ohci, int addr,
593 			  int clear_bits, int set_bits)
594 {
595 	int ret = read_phy_reg(ohci, addr);
596 	if (ret < 0)
597 		return ret;
598 
599 	/*
600 	 * The interrupt status bits are cleared by writing a one bit.
601 	 * Avoid clearing them unless explicitly requested in set_bits.
602 	 */
603 	if (addr == 5)
604 		clear_bits |= PHY_INT_STATUS_BITS;
605 
606 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
607 }
608 
609 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
610 {
611 	int ret;
612 
613 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
614 	if (ret < 0)
615 		return ret;
616 
617 	return read_phy_reg(ohci, addr);
618 }
619 
620 static int ohci_read_phy_reg(struct fw_card *card, int addr)
621 {
622 	struct fw_ohci *ohci = fw_ohci(card);
623 	int ret;
624 
625 	mutex_lock(&ohci->phy_reg_mutex);
626 	ret = read_phy_reg(ohci, addr);
627 	mutex_unlock(&ohci->phy_reg_mutex);
628 
629 	return ret;
630 }
631 
632 static int ohci_update_phy_reg(struct fw_card *card, int addr,
633 			       int clear_bits, int set_bits)
634 {
635 	struct fw_ohci *ohci = fw_ohci(card);
636 	int ret;
637 
638 	mutex_lock(&ohci->phy_reg_mutex);
639 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
640 	mutex_unlock(&ohci->phy_reg_mutex);
641 
642 	return ret;
643 }
644 
645 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
646 {
647 	return page_private(ctx->pages[i]);
648 }
649 
650 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
651 {
652 	struct descriptor *d;
653 
654 	d = &ctx->descriptors[index];
655 	d->branch_address  &= cpu_to_le32(~0xf);
656 	d->res_count       =  cpu_to_le16(PAGE_SIZE);
657 	d->transfer_status =  0;
658 
659 	wmb(); /* finish init of new descriptors before branch_address update */
660 	d = &ctx->descriptors[ctx->last_buffer_index];
661 	d->branch_address  |= cpu_to_le32(1);
662 
663 	ctx->last_buffer_index = index;
664 
665 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
666 }
667 
668 static void ar_context_release(struct ar_context *ctx)
669 {
670 	unsigned int i;
671 
672 	if (ctx->buffer)
673 		vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
674 
675 	for (i = 0; i < AR_BUFFERS; i++)
676 		if (ctx->pages[i]) {
677 			dma_unmap_page(ctx->ohci->card.device,
678 				       ar_buffer_bus(ctx, i),
679 				       PAGE_SIZE, DMA_FROM_DEVICE);
680 			__free_page(ctx->pages[i]);
681 		}
682 }
683 
684 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
685 {
686 	struct fw_ohci *ohci = ctx->ohci;
687 
688 	if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
689 		reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
690 		flush_writes(ohci);
691 
692 		dev_err(ohci->card.device, "AR error: %s; DMA stopped\n",
693 			error_msg);
694 	}
695 	/* FIXME: restart? */
696 }
697 
698 static inline unsigned int ar_next_buffer_index(unsigned int index)
699 {
700 	return (index + 1) % AR_BUFFERS;
701 }
702 
703 static inline unsigned int ar_prev_buffer_index(unsigned int index)
704 {
705 	return (index - 1 + AR_BUFFERS) % AR_BUFFERS;
706 }
707 
708 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
709 {
710 	return ar_next_buffer_index(ctx->last_buffer_index);
711 }
712 
713 /*
714  * We search for the buffer that contains the last AR packet DMA data written
715  * by the controller.
716  */
717 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
718 						 unsigned int *buffer_offset)
719 {
720 	unsigned int i, next_i, last = ctx->last_buffer_index;
721 	__le16 res_count, next_res_count;
722 
723 	i = ar_first_buffer_index(ctx);
724 	res_count = ACCESS_ONCE(ctx->descriptors[i].res_count);
725 
726 	/* A buffer that is not yet completely filled must be the last one. */
727 	while (i != last && res_count == 0) {
728 
729 		/* Peek at the next descriptor. */
730 		next_i = ar_next_buffer_index(i);
731 		rmb(); /* read descriptors in order */
732 		next_res_count = ACCESS_ONCE(
733 				ctx->descriptors[next_i].res_count);
734 		/*
735 		 * If the next descriptor is still empty, we must stop at this
736 		 * descriptor.
737 		 */
738 		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
739 			/*
740 			 * The exception is when the DMA data for one packet is
741 			 * split over three buffers; in this case, the middle
742 			 * buffer's descriptor might be never updated by the
743 			 * controller and look still empty, and we have to peek
744 			 * at the third one.
745 			 */
746 			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
747 				next_i = ar_next_buffer_index(next_i);
748 				rmb();
749 				next_res_count = ACCESS_ONCE(
750 					ctx->descriptors[next_i].res_count);
751 				if (next_res_count != cpu_to_le16(PAGE_SIZE))
752 					goto next_buffer_is_active;
753 			}
754 
755 			break;
756 		}
757 
758 next_buffer_is_active:
759 		i = next_i;
760 		res_count = next_res_count;
761 	}
762 
763 	rmb(); /* read res_count before the DMA data */
764 
765 	*buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
766 	if (*buffer_offset > PAGE_SIZE) {
767 		*buffer_offset = 0;
768 		ar_context_abort(ctx, "corrupted descriptor");
769 	}
770 
771 	return i;
772 }
773 
774 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
775 				    unsigned int end_buffer_index,
776 				    unsigned int end_buffer_offset)
777 {
778 	unsigned int i;
779 
780 	i = ar_first_buffer_index(ctx);
781 	while (i != end_buffer_index) {
782 		dma_sync_single_for_cpu(ctx->ohci->card.device,
783 					ar_buffer_bus(ctx, i),
784 					PAGE_SIZE, DMA_FROM_DEVICE);
785 		i = ar_next_buffer_index(i);
786 	}
787 	if (end_buffer_offset > 0)
788 		dma_sync_single_for_cpu(ctx->ohci->card.device,
789 					ar_buffer_bus(ctx, i),
790 					end_buffer_offset, DMA_FROM_DEVICE);
791 }
792 
793 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
794 #define cond_le32_to_cpu(v) \
795 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
796 #else
797 #define cond_le32_to_cpu(v) le32_to_cpu(v)
798 #endif
799 
800 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
801 {
802 	struct fw_ohci *ohci = ctx->ohci;
803 	struct fw_packet p;
804 	u32 status, length, tcode;
805 	int evt;
806 
807 	p.header[0] = cond_le32_to_cpu(buffer[0]);
808 	p.header[1] = cond_le32_to_cpu(buffer[1]);
809 	p.header[2] = cond_le32_to_cpu(buffer[2]);
810 
811 	tcode = (p.header[0] >> 4) & 0x0f;
812 	switch (tcode) {
813 	case TCODE_WRITE_QUADLET_REQUEST:
814 	case TCODE_READ_QUADLET_RESPONSE:
815 		p.header[3] = (__force __u32) buffer[3];
816 		p.header_length = 16;
817 		p.payload_length = 0;
818 		break;
819 
820 	case TCODE_READ_BLOCK_REQUEST :
821 		p.header[3] = cond_le32_to_cpu(buffer[3]);
822 		p.header_length = 16;
823 		p.payload_length = 0;
824 		break;
825 
826 	case TCODE_WRITE_BLOCK_REQUEST:
827 	case TCODE_READ_BLOCK_RESPONSE:
828 	case TCODE_LOCK_REQUEST:
829 	case TCODE_LOCK_RESPONSE:
830 		p.header[3] = cond_le32_to_cpu(buffer[3]);
831 		p.header_length = 16;
832 		p.payload_length = p.header[3] >> 16;
833 		if (p.payload_length > MAX_ASYNC_PAYLOAD) {
834 			ar_context_abort(ctx, "invalid packet length");
835 			return NULL;
836 		}
837 		break;
838 
839 	case TCODE_WRITE_RESPONSE:
840 	case TCODE_READ_QUADLET_REQUEST:
841 	case OHCI_TCODE_PHY_PACKET:
842 		p.header_length = 12;
843 		p.payload_length = 0;
844 		break;
845 
846 	default:
847 		ar_context_abort(ctx, "invalid tcode");
848 		return NULL;
849 	}
850 
851 	p.payload = (void *) buffer + p.header_length;
852 
853 	/* FIXME: What to do about evt_* errors? */
854 	length = (p.header_length + p.payload_length + 3) / 4;
855 	status = cond_le32_to_cpu(buffer[length]);
856 	evt    = (status >> 16) & 0x1f;
857 
858 	p.ack        = evt - 16;
859 	p.speed      = (status >> 21) & 0x7;
860 	p.timestamp  = status & 0xffff;
861 	p.generation = ohci->request_generation;
862 
863 	log_ar_at_event(ohci, 'R', p.speed, p.header, evt);
864 
865 	/*
866 	 * Several controllers, notably from NEC and VIA, forget to
867 	 * write ack_complete status at PHY packet reception.
868 	 */
869 	if (evt == OHCI1394_evt_no_status &&
870 	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
871 		p.ack = ACK_COMPLETE;
872 
873 	/*
874 	 * The OHCI bus reset handler synthesizes a PHY packet with
875 	 * the new generation number when a bus reset happens (see
876 	 * section 8.4.2.3).  This helps us determine when a request
877 	 * was received and make sure we send the response in the same
878 	 * generation.  We only need this for requests; for responses
879 	 * we use the unique tlabel for finding the matching
880 	 * request.
881 	 *
882 	 * Alas some chips sometimes emit bus reset packets with a
883 	 * wrong generation.  We set the correct generation for these
884 	 * at a slightly incorrect time (in bus_reset_work).
885 	 */
886 	if (evt == OHCI1394_evt_bus_reset) {
887 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
888 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
889 	} else if (ctx == &ohci->ar_request_ctx) {
890 		fw_core_handle_request(&ohci->card, &p);
891 	} else {
892 		fw_core_handle_response(&ohci->card, &p);
893 	}
894 
895 	return buffer + length + 1;
896 }
897 
898 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
899 {
900 	void *next;
901 
902 	while (p < end) {
903 		next = handle_ar_packet(ctx, p);
904 		if (!next)
905 			return p;
906 		p = next;
907 	}
908 
909 	return p;
910 }
911 
912 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
913 {
914 	unsigned int i;
915 
916 	i = ar_first_buffer_index(ctx);
917 	while (i != end_buffer) {
918 		dma_sync_single_for_device(ctx->ohci->card.device,
919 					   ar_buffer_bus(ctx, i),
920 					   PAGE_SIZE, DMA_FROM_DEVICE);
921 		ar_context_link_page(ctx, i);
922 		i = ar_next_buffer_index(i);
923 	}
924 }
925 
926 static void ar_context_tasklet(unsigned long data)
927 {
928 	struct ar_context *ctx = (struct ar_context *)data;
929 	unsigned int end_buffer_index, end_buffer_offset;
930 	void *p, *end;
931 
932 	p = ctx->pointer;
933 	if (!p)
934 		return;
935 
936 	end_buffer_index = ar_search_last_active_buffer(ctx,
937 							&end_buffer_offset);
938 	ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
939 	end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
940 
941 	if (end_buffer_index < ar_first_buffer_index(ctx)) {
942 		/*
943 		 * The filled part of the overall buffer wraps around; handle
944 		 * all packets up to the buffer end here.  If the last packet
945 		 * wraps around, its tail will be visible after the buffer end
946 		 * because the buffer start pages are mapped there again.
947 		 */
948 		void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
949 		p = handle_ar_packets(ctx, p, buffer_end);
950 		if (p < buffer_end)
951 			goto error;
952 		/* adjust p to point back into the actual buffer */
953 		p -= AR_BUFFERS * PAGE_SIZE;
954 	}
955 
956 	p = handle_ar_packets(ctx, p, end);
957 	if (p != end) {
958 		if (p > end)
959 			ar_context_abort(ctx, "inconsistent descriptor");
960 		goto error;
961 	}
962 
963 	ctx->pointer = p;
964 	ar_recycle_buffers(ctx, end_buffer_index);
965 
966 	return;
967 
968 error:
969 	ctx->pointer = NULL;
970 }
971 
972 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
973 			   unsigned int descriptors_offset, u32 regs)
974 {
975 	unsigned int i;
976 	dma_addr_t dma_addr;
977 	struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
978 	struct descriptor *d;
979 
980 	ctx->regs        = regs;
981 	ctx->ohci        = ohci;
982 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
983 
984 	for (i = 0; i < AR_BUFFERS; i++) {
985 		ctx->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32);
986 		if (!ctx->pages[i])
987 			goto out_of_memory;
988 		dma_addr = dma_map_page(ohci->card.device, ctx->pages[i],
989 					0, PAGE_SIZE, DMA_FROM_DEVICE);
990 		if (dma_mapping_error(ohci->card.device, dma_addr)) {
991 			__free_page(ctx->pages[i]);
992 			ctx->pages[i] = NULL;
993 			goto out_of_memory;
994 		}
995 		set_page_private(ctx->pages[i], dma_addr);
996 	}
997 
998 	for (i = 0; i < AR_BUFFERS; i++)
999 		pages[i]              = ctx->pages[i];
1000 	for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
1001 		pages[AR_BUFFERS + i] = ctx->pages[i];
1002 	ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
1003 				 -1, PAGE_KERNEL);
1004 	if (!ctx->buffer)
1005 		goto out_of_memory;
1006 
1007 	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
1008 	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
1009 
1010 	for (i = 0; i < AR_BUFFERS; i++) {
1011 		d = &ctx->descriptors[i];
1012 		d->req_count      = cpu_to_le16(PAGE_SIZE);
1013 		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
1014 						DESCRIPTOR_STATUS |
1015 						DESCRIPTOR_BRANCH_ALWAYS);
1016 		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
1017 		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
1018 			ar_next_buffer_index(i) * sizeof(struct descriptor));
1019 	}
1020 
1021 	return 0;
1022 
1023 out_of_memory:
1024 	ar_context_release(ctx);
1025 
1026 	return -ENOMEM;
1027 }
1028 
1029 static void ar_context_run(struct ar_context *ctx)
1030 {
1031 	unsigned int i;
1032 
1033 	for (i = 0; i < AR_BUFFERS; i++)
1034 		ar_context_link_page(ctx, i);
1035 
1036 	ctx->pointer = ctx->buffer;
1037 
1038 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1039 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1040 }
1041 
1042 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1043 {
1044 	__le16 branch;
1045 
1046 	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1047 
1048 	/* figure out which descriptor the branch address goes in */
1049 	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1050 		return d;
1051 	else
1052 		return d + z - 1;
1053 }
1054 
1055 static void context_tasklet(unsigned long data)
1056 {
1057 	struct context *ctx = (struct context *) data;
1058 	struct descriptor *d, *last;
1059 	u32 address;
1060 	int z;
1061 	struct descriptor_buffer *desc;
1062 
1063 	desc = list_entry(ctx->buffer_list.next,
1064 			struct descriptor_buffer, list);
1065 	last = ctx->last;
1066 	while (last->branch_address != 0) {
1067 		struct descriptor_buffer *old_desc = desc;
1068 		address = le32_to_cpu(last->branch_address);
1069 		z = address & 0xf;
1070 		address &= ~0xf;
1071 		ctx->current_bus = address;
1072 
1073 		/* If the branch address points to a buffer outside of the
1074 		 * current buffer, advance to the next buffer. */
1075 		if (address < desc->buffer_bus ||
1076 				address >= desc->buffer_bus + desc->used)
1077 			desc = list_entry(desc->list.next,
1078 					struct descriptor_buffer, list);
1079 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1080 		last = find_branch_descriptor(d, z);
1081 
1082 		if (!ctx->callback(ctx, d, last))
1083 			break;
1084 
1085 		if (old_desc != desc) {
1086 			/* If we've advanced to the next buffer, move the
1087 			 * previous buffer to the free list. */
1088 			unsigned long flags;
1089 			old_desc->used = 0;
1090 			spin_lock_irqsave(&ctx->ohci->lock, flags);
1091 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1092 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1093 		}
1094 		ctx->last = last;
1095 	}
1096 }
1097 
1098 /*
1099  * Allocate a new buffer and add it to the list of free buffers for this
1100  * context.  Must be called with ohci->lock held.
1101  */
1102 static int context_add_buffer(struct context *ctx)
1103 {
1104 	struct descriptor_buffer *desc;
1105 	dma_addr_t uninitialized_var(bus_addr);
1106 	int offset;
1107 
1108 	/*
1109 	 * 16MB of descriptors should be far more than enough for any DMA
1110 	 * program.  This will catch run-away userspace or DoS attacks.
1111 	 */
1112 	if (ctx->total_allocation >= 16*1024*1024)
1113 		return -ENOMEM;
1114 
1115 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1116 			&bus_addr, GFP_ATOMIC);
1117 	if (!desc)
1118 		return -ENOMEM;
1119 
1120 	offset = (void *)&desc->buffer - (void *)desc;
1121 	desc->buffer_size = PAGE_SIZE - offset;
1122 	desc->buffer_bus = bus_addr + offset;
1123 	desc->used = 0;
1124 
1125 	list_add_tail(&desc->list, &ctx->buffer_list);
1126 	ctx->total_allocation += PAGE_SIZE;
1127 
1128 	return 0;
1129 }
1130 
1131 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1132 			u32 regs, descriptor_callback_t callback)
1133 {
1134 	ctx->ohci = ohci;
1135 	ctx->regs = regs;
1136 	ctx->total_allocation = 0;
1137 
1138 	INIT_LIST_HEAD(&ctx->buffer_list);
1139 	if (context_add_buffer(ctx) < 0)
1140 		return -ENOMEM;
1141 
1142 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1143 			struct descriptor_buffer, list);
1144 
1145 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1146 	ctx->callback = callback;
1147 
1148 	/*
1149 	 * We put a dummy descriptor in the buffer that has a NULL
1150 	 * branch address and looks like it's been sent.  That way we
1151 	 * have a descriptor to append DMA programs to.
1152 	 */
1153 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1154 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1155 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1156 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1157 	ctx->last = ctx->buffer_tail->buffer;
1158 	ctx->prev = ctx->buffer_tail->buffer;
1159 
1160 	return 0;
1161 }
1162 
1163 static void context_release(struct context *ctx)
1164 {
1165 	struct fw_card *card = &ctx->ohci->card;
1166 	struct descriptor_buffer *desc, *tmp;
1167 
1168 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1169 		dma_free_coherent(card->device, PAGE_SIZE, desc,
1170 			desc->buffer_bus -
1171 			((void *)&desc->buffer - (void *)desc));
1172 }
1173 
1174 /* Must be called with ohci->lock held */
1175 static struct descriptor *context_get_descriptors(struct context *ctx,
1176 						  int z, dma_addr_t *d_bus)
1177 {
1178 	struct descriptor *d = NULL;
1179 	struct descriptor_buffer *desc = ctx->buffer_tail;
1180 
1181 	if (z * sizeof(*d) > desc->buffer_size)
1182 		return NULL;
1183 
1184 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1185 		/* No room for the descriptor in this buffer, so advance to the
1186 		 * next one. */
1187 
1188 		if (desc->list.next == &ctx->buffer_list) {
1189 			/* If there is no free buffer next in the list,
1190 			 * allocate one. */
1191 			if (context_add_buffer(ctx) < 0)
1192 				return NULL;
1193 		}
1194 		desc = list_entry(desc->list.next,
1195 				struct descriptor_buffer, list);
1196 		ctx->buffer_tail = desc;
1197 	}
1198 
1199 	d = desc->buffer + desc->used / sizeof(*d);
1200 	memset(d, 0, z * sizeof(*d));
1201 	*d_bus = desc->buffer_bus + desc->used;
1202 
1203 	return d;
1204 }
1205 
1206 static void context_run(struct context *ctx, u32 extra)
1207 {
1208 	struct fw_ohci *ohci = ctx->ohci;
1209 
1210 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1211 		  le32_to_cpu(ctx->last->branch_address));
1212 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1213 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1214 	ctx->running = true;
1215 	flush_writes(ohci);
1216 }
1217 
1218 static void context_append(struct context *ctx,
1219 			   struct descriptor *d, int z, int extra)
1220 {
1221 	dma_addr_t d_bus;
1222 	struct descriptor_buffer *desc = ctx->buffer_tail;
1223 
1224 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1225 
1226 	desc->used += (z + extra) * sizeof(*d);
1227 
1228 	wmb(); /* finish init of new descriptors before branch_address update */
1229 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1230 	ctx->prev = find_branch_descriptor(d, z);
1231 }
1232 
1233 static void context_stop(struct context *ctx)
1234 {
1235 	struct fw_ohci *ohci = ctx->ohci;
1236 	u32 reg;
1237 	int i;
1238 
1239 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1240 	ctx->running = false;
1241 
1242 	for (i = 0; i < 1000; i++) {
1243 		reg = reg_read(ohci, CONTROL_SET(ctx->regs));
1244 		if ((reg & CONTEXT_ACTIVE) == 0)
1245 			return;
1246 
1247 		if (i)
1248 			udelay(10);
1249 	}
1250 	dev_err(ohci->card.device, "DMA context still active (0x%08x)\n", reg);
1251 }
1252 
1253 struct driver_data {
1254 	u8 inline_data[8];
1255 	struct fw_packet *packet;
1256 };
1257 
1258 /*
1259  * This function apppends a packet to the DMA queue for transmission.
1260  * Must always be called with the ochi->lock held to ensure proper
1261  * generation handling and locking around packet queue manipulation.
1262  */
1263 static int at_context_queue_packet(struct context *ctx,
1264 				   struct fw_packet *packet)
1265 {
1266 	struct fw_ohci *ohci = ctx->ohci;
1267 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1268 	struct driver_data *driver_data;
1269 	struct descriptor *d, *last;
1270 	__le32 *header;
1271 	int z, tcode;
1272 
1273 	d = context_get_descriptors(ctx, 4, &d_bus);
1274 	if (d == NULL) {
1275 		packet->ack = RCODE_SEND_ERROR;
1276 		return -1;
1277 	}
1278 
1279 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1280 	d[0].res_count = cpu_to_le16(packet->timestamp);
1281 
1282 	/*
1283 	 * The DMA format for asyncronous link packets is different
1284 	 * from the IEEE1394 layout, so shift the fields around
1285 	 * accordingly.
1286 	 */
1287 
1288 	tcode = (packet->header[0] >> 4) & 0x0f;
1289 	header = (__le32 *) &d[1];
1290 	switch (tcode) {
1291 	case TCODE_WRITE_QUADLET_REQUEST:
1292 	case TCODE_WRITE_BLOCK_REQUEST:
1293 	case TCODE_WRITE_RESPONSE:
1294 	case TCODE_READ_QUADLET_REQUEST:
1295 	case TCODE_READ_BLOCK_REQUEST:
1296 	case TCODE_READ_QUADLET_RESPONSE:
1297 	case TCODE_READ_BLOCK_RESPONSE:
1298 	case TCODE_LOCK_REQUEST:
1299 	case TCODE_LOCK_RESPONSE:
1300 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1301 					(packet->speed << 16));
1302 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1303 					(packet->header[0] & 0xffff0000));
1304 		header[2] = cpu_to_le32(packet->header[2]);
1305 
1306 		if (TCODE_IS_BLOCK_PACKET(tcode))
1307 			header[3] = cpu_to_le32(packet->header[3]);
1308 		else
1309 			header[3] = (__force __le32) packet->header[3];
1310 
1311 		d[0].req_count = cpu_to_le16(packet->header_length);
1312 		break;
1313 
1314 	case TCODE_LINK_INTERNAL:
1315 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1316 					(packet->speed << 16));
1317 		header[1] = cpu_to_le32(packet->header[1]);
1318 		header[2] = cpu_to_le32(packet->header[2]);
1319 		d[0].req_count = cpu_to_le16(12);
1320 
1321 		if (is_ping_packet(&packet->header[1]))
1322 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1323 		break;
1324 
1325 	case TCODE_STREAM_DATA:
1326 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1327 					(packet->speed << 16));
1328 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1329 		d[0].req_count = cpu_to_le16(8);
1330 		break;
1331 
1332 	default:
1333 		/* BUG(); */
1334 		packet->ack = RCODE_SEND_ERROR;
1335 		return -1;
1336 	}
1337 
1338 	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1339 	driver_data = (struct driver_data *) &d[3];
1340 	driver_data->packet = packet;
1341 	packet->driver_data = driver_data;
1342 
1343 	if (packet->payload_length > 0) {
1344 		if (packet->payload_length > sizeof(driver_data->inline_data)) {
1345 			payload_bus = dma_map_single(ohci->card.device,
1346 						     packet->payload,
1347 						     packet->payload_length,
1348 						     DMA_TO_DEVICE);
1349 			if (dma_mapping_error(ohci->card.device, payload_bus)) {
1350 				packet->ack = RCODE_SEND_ERROR;
1351 				return -1;
1352 			}
1353 			packet->payload_bus	= payload_bus;
1354 			packet->payload_mapped	= true;
1355 		} else {
1356 			memcpy(driver_data->inline_data, packet->payload,
1357 			       packet->payload_length);
1358 			payload_bus = d_bus + 3 * sizeof(*d);
1359 		}
1360 
1361 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1362 		d[2].data_address = cpu_to_le32(payload_bus);
1363 		last = &d[2];
1364 		z = 3;
1365 	} else {
1366 		last = &d[0];
1367 		z = 2;
1368 	}
1369 
1370 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1371 				     DESCRIPTOR_IRQ_ALWAYS |
1372 				     DESCRIPTOR_BRANCH_ALWAYS);
1373 
1374 	/* FIXME: Document how the locking works. */
1375 	if (ohci->generation != packet->generation) {
1376 		if (packet->payload_mapped)
1377 			dma_unmap_single(ohci->card.device, payload_bus,
1378 					 packet->payload_length, DMA_TO_DEVICE);
1379 		packet->ack = RCODE_GENERATION;
1380 		return -1;
1381 	}
1382 
1383 	context_append(ctx, d, z, 4 - z);
1384 
1385 	if (ctx->running)
1386 		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1387 	else
1388 		context_run(ctx, 0);
1389 
1390 	return 0;
1391 }
1392 
1393 static void at_context_flush(struct context *ctx)
1394 {
1395 	tasklet_disable(&ctx->tasklet);
1396 
1397 	ctx->flushing = true;
1398 	context_tasklet((unsigned long)ctx);
1399 	ctx->flushing = false;
1400 
1401 	tasklet_enable(&ctx->tasklet);
1402 }
1403 
1404 static int handle_at_packet(struct context *context,
1405 			    struct descriptor *d,
1406 			    struct descriptor *last)
1407 {
1408 	struct driver_data *driver_data;
1409 	struct fw_packet *packet;
1410 	struct fw_ohci *ohci = context->ohci;
1411 	int evt;
1412 
1413 	if (last->transfer_status == 0 && !context->flushing)
1414 		/* This descriptor isn't done yet, stop iteration. */
1415 		return 0;
1416 
1417 	driver_data = (struct driver_data *) &d[3];
1418 	packet = driver_data->packet;
1419 	if (packet == NULL)
1420 		/* This packet was cancelled, just continue. */
1421 		return 1;
1422 
1423 	if (packet->payload_mapped)
1424 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1425 				 packet->payload_length, DMA_TO_DEVICE);
1426 
1427 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1428 	packet->timestamp = le16_to_cpu(last->res_count);
1429 
1430 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);
1431 
1432 	switch (evt) {
1433 	case OHCI1394_evt_timeout:
1434 		/* Async response transmit timed out. */
1435 		packet->ack = RCODE_CANCELLED;
1436 		break;
1437 
1438 	case OHCI1394_evt_flushed:
1439 		/*
1440 		 * The packet was flushed should give same error as
1441 		 * when we try to use a stale generation count.
1442 		 */
1443 		packet->ack = RCODE_GENERATION;
1444 		break;
1445 
1446 	case OHCI1394_evt_missing_ack:
1447 		if (context->flushing)
1448 			packet->ack = RCODE_GENERATION;
1449 		else {
1450 			/*
1451 			 * Using a valid (current) generation count, but the
1452 			 * node is not on the bus or not sending acks.
1453 			 */
1454 			packet->ack = RCODE_NO_ACK;
1455 		}
1456 		break;
1457 
1458 	case ACK_COMPLETE + 0x10:
1459 	case ACK_PENDING + 0x10:
1460 	case ACK_BUSY_X + 0x10:
1461 	case ACK_BUSY_A + 0x10:
1462 	case ACK_BUSY_B + 0x10:
1463 	case ACK_DATA_ERROR + 0x10:
1464 	case ACK_TYPE_ERROR + 0x10:
1465 		packet->ack = evt - 0x10;
1466 		break;
1467 
1468 	case OHCI1394_evt_no_status:
1469 		if (context->flushing) {
1470 			packet->ack = RCODE_GENERATION;
1471 			break;
1472 		}
1473 		/* fall through */
1474 
1475 	default:
1476 		packet->ack = RCODE_SEND_ERROR;
1477 		break;
1478 	}
1479 
1480 	packet->callback(packet, &ohci->card, packet->ack);
1481 
1482 	return 1;
1483 }
1484 
1485 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1486 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1487 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1488 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1489 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1490 
1491 static void handle_local_rom(struct fw_ohci *ohci,
1492 			     struct fw_packet *packet, u32 csr)
1493 {
1494 	struct fw_packet response;
1495 	int tcode, length, i;
1496 
1497 	tcode = HEADER_GET_TCODE(packet->header[0]);
1498 	if (TCODE_IS_BLOCK_PACKET(tcode))
1499 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1500 	else
1501 		length = 4;
1502 
1503 	i = csr - CSR_CONFIG_ROM;
1504 	if (i + length > CONFIG_ROM_SIZE) {
1505 		fw_fill_response(&response, packet->header,
1506 				 RCODE_ADDRESS_ERROR, NULL, 0);
1507 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1508 		fw_fill_response(&response, packet->header,
1509 				 RCODE_TYPE_ERROR, NULL, 0);
1510 	} else {
1511 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1512 				 (void *) ohci->config_rom + i, length);
1513 	}
1514 
1515 	fw_core_handle_response(&ohci->card, &response);
1516 }
1517 
1518 static void handle_local_lock(struct fw_ohci *ohci,
1519 			      struct fw_packet *packet, u32 csr)
1520 {
1521 	struct fw_packet response;
1522 	int tcode, length, ext_tcode, sel, try;
1523 	__be32 *payload, lock_old;
1524 	u32 lock_arg, lock_data;
1525 
1526 	tcode = HEADER_GET_TCODE(packet->header[0]);
1527 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1528 	payload = packet->payload;
1529 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1530 
1531 	if (tcode == TCODE_LOCK_REQUEST &&
1532 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1533 		lock_arg = be32_to_cpu(payload[0]);
1534 		lock_data = be32_to_cpu(payload[1]);
1535 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1536 		lock_arg = 0;
1537 		lock_data = 0;
1538 	} else {
1539 		fw_fill_response(&response, packet->header,
1540 				 RCODE_TYPE_ERROR, NULL, 0);
1541 		goto out;
1542 	}
1543 
1544 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1545 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1546 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1547 	reg_write(ohci, OHCI1394_CSRControl, sel);
1548 
1549 	for (try = 0; try < 20; try++)
1550 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1551 			lock_old = cpu_to_be32(reg_read(ohci,
1552 							OHCI1394_CSRData));
1553 			fw_fill_response(&response, packet->header,
1554 					 RCODE_COMPLETE,
1555 					 &lock_old, sizeof(lock_old));
1556 			goto out;
1557 		}
1558 
1559 	dev_err(ohci->card.device, "swap not done (CSR lock timeout)\n");
1560 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1561 
1562  out:
1563 	fw_core_handle_response(&ohci->card, &response);
1564 }
1565 
1566 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1567 {
1568 	u64 offset, csr;
1569 
1570 	if (ctx == &ctx->ohci->at_request_ctx) {
1571 		packet->ack = ACK_PENDING;
1572 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1573 	}
1574 
1575 	offset =
1576 		((unsigned long long)
1577 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1578 		packet->header[2];
1579 	csr = offset - CSR_REGISTER_BASE;
1580 
1581 	/* Handle config rom reads. */
1582 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1583 		handle_local_rom(ctx->ohci, packet, csr);
1584 	else switch (csr) {
1585 	case CSR_BUS_MANAGER_ID:
1586 	case CSR_BANDWIDTH_AVAILABLE:
1587 	case CSR_CHANNELS_AVAILABLE_HI:
1588 	case CSR_CHANNELS_AVAILABLE_LO:
1589 		handle_local_lock(ctx->ohci, packet, csr);
1590 		break;
1591 	default:
1592 		if (ctx == &ctx->ohci->at_request_ctx)
1593 			fw_core_handle_request(&ctx->ohci->card, packet);
1594 		else
1595 			fw_core_handle_response(&ctx->ohci->card, packet);
1596 		break;
1597 	}
1598 
1599 	if (ctx == &ctx->ohci->at_response_ctx) {
1600 		packet->ack = ACK_COMPLETE;
1601 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1602 	}
1603 }
1604 
1605 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1606 {
1607 	unsigned long flags;
1608 	int ret;
1609 
1610 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1611 
1612 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1613 	    ctx->ohci->generation == packet->generation) {
1614 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1615 		handle_local_request(ctx, packet);
1616 		return;
1617 	}
1618 
1619 	ret = at_context_queue_packet(ctx, packet);
1620 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1621 
1622 	if (ret < 0)
1623 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1624 
1625 }
1626 
1627 static void detect_dead_context(struct fw_ohci *ohci,
1628 				const char *name, unsigned int regs)
1629 {
1630 	u32 ctl;
1631 
1632 	ctl = reg_read(ohci, CONTROL_SET(regs));
1633 	if (ctl & CONTEXT_DEAD)
1634 		dev_err(ohci->card.device,
1635 			"DMA context %s has stopped, error code: %s\n",
1636 			name, evts[ctl & 0x1f]);
1637 }
1638 
1639 static void handle_dead_contexts(struct fw_ohci *ohci)
1640 {
1641 	unsigned int i;
1642 	char name[8];
1643 
1644 	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1645 	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1646 	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1647 	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1648 	for (i = 0; i < 32; ++i) {
1649 		if (!(ohci->it_context_support & (1 << i)))
1650 			continue;
1651 		sprintf(name, "IT%u", i);
1652 		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1653 	}
1654 	for (i = 0; i < 32; ++i) {
1655 		if (!(ohci->ir_context_support & (1 << i)))
1656 			continue;
1657 		sprintf(name, "IR%u", i);
1658 		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1659 	}
1660 	/* TODO: maybe try to flush and restart the dead contexts */
1661 }
1662 
1663 static u32 cycle_timer_ticks(u32 cycle_timer)
1664 {
1665 	u32 ticks;
1666 
1667 	ticks = cycle_timer & 0xfff;
1668 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1669 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1670 
1671 	return ticks;
1672 }
1673 
1674 /*
1675  * Some controllers exhibit one or more of the following bugs when updating the
1676  * iso cycle timer register:
1677  *  - When the lowest six bits are wrapping around to zero, a read that happens
1678  *    at the same time will return garbage in the lowest ten bits.
1679  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1680  *    not incremented for about 60 ns.
1681  *  - Occasionally, the entire register reads zero.
1682  *
1683  * To catch these, we read the register three times and ensure that the
1684  * difference between each two consecutive reads is approximately the same, i.e.
1685  * less than twice the other.  Furthermore, any negative difference indicates an
1686  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1687  * execute, so we have enough precision to compute the ratio of the differences.)
1688  */
1689 static u32 get_cycle_time(struct fw_ohci *ohci)
1690 {
1691 	u32 c0, c1, c2;
1692 	u32 t0, t1, t2;
1693 	s32 diff01, diff12;
1694 	int i;
1695 
1696 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1697 
1698 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1699 		i = 0;
1700 		c1 = c2;
1701 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1702 		do {
1703 			c0 = c1;
1704 			c1 = c2;
1705 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1706 			t0 = cycle_timer_ticks(c0);
1707 			t1 = cycle_timer_ticks(c1);
1708 			t2 = cycle_timer_ticks(c2);
1709 			diff01 = t1 - t0;
1710 			diff12 = t2 - t1;
1711 		} while ((diff01 <= 0 || diff12 <= 0 ||
1712 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1713 			 && i++ < 20);
1714 	}
1715 
1716 	return c2;
1717 }
1718 
1719 /*
1720  * This function has to be called at least every 64 seconds.  The bus_time
1721  * field stores not only the upper 25 bits of the BUS_TIME register but also
1722  * the most significant bit of the cycle timer in bit 6 so that we can detect
1723  * changes in this bit.
1724  */
1725 static u32 update_bus_time(struct fw_ohci *ohci)
1726 {
1727 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1728 
1729 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1730 		ohci->bus_time += 0x40;
1731 
1732 	return ohci->bus_time | cycle_time_seconds;
1733 }
1734 
1735 static int get_status_for_port(struct fw_ohci *ohci, int port_index)
1736 {
1737 	int reg;
1738 
1739 	mutex_lock(&ohci->phy_reg_mutex);
1740 	reg = write_phy_reg(ohci, 7, port_index);
1741 	if (reg >= 0)
1742 		reg = read_phy_reg(ohci, 8);
1743 	mutex_unlock(&ohci->phy_reg_mutex);
1744 	if (reg < 0)
1745 		return reg;
1746 
1747 	switch (reg & 0x0f) {
1748 	case 0x06:
1749 		return 2;	/* is child node (connected to parent node) */
1750 	case 0x0e:
1751 		return 3;	/* is parent node (connected to child node) */
1752 	}
1753 	return 1;		/* not connected */
1754 }
1755 
1756 static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
1757 	int self_id_count)
1758 {
1759 	int i;
1760 	u32 entry;
1761 
1762 	for (i = 0; i < self_id_count; i++) {
1763 		entry = ohci->self_id_buffer[i];
1764 		if ((self_id & 0xff000000) == (entry & 0xff000000))
1765 			return -1;
1766 		if ((self_id & 0xff000000) < (entry & 0xff000000))
1767 			return i;
1768 	}
1769 	return i;
1770 }
1771 
1772 /*
1773  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1774  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1775  * Construct the selfID from phy register contents.
1776  * FIXME:  How to determine the selfID.i flag?
1777  */
1778 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
1779 {
1780 	int reg, i, pos, status;
1781 	/* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
1782 	u32 self_id = 0x8040c800;
1783 
1784 	reg = reg_read(ohci, OHCI1394_NodeID);
1785 	if (!(reg & OHCI1394_NodeID_idValid)) {
1786 		dev_notice(ohci->card.device,
1787 			   "node ID not valid, new bus reset in progress\n");
1788 		return -EBUSY;
1789 	}
1790 	self_id |= ((reg & 0x3f) << 24); /* phy ID */
1791 
1792 	reg = ohci_read_phy_reg(&ohci->card, 4);
1793 	if (reg < 0)
1794 		return reg;
1795 	self_id |= ((reg & 0x07) << 8); /* power class */
1796 
1797 	reg = ohci_read_phy_reg(&ohci->card, 1);
1798 	if (reg < 0)
1799 		return reg;
1800 	self_id |= ((reg & 0x3f) << 16); /* gap count */
1801 
1802 	for (i = 0; i < 3; i++) {
1803 		status = get_status_for_port(ohci, i);
1804 		if (status < 0)
1805 			return status;
1806 		self_id |= ((status & 0x3) << (6 - (i * 2)));
1807 	}
1808 
1809 	pos = get_self_id_pos(ohci, self_id, self_id_count);
1810 	if (pos >= 0) {
1811 		memmove(&(ohci->self_id_buffer[pos+1]),
1812 			&(ohci->self_id_buffer[pos]),
1813 			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
1814 		ohci->self_id_buffer[pos] = self_id;
1815 		self_id_count++;
1816 	}
1817 	return self_id_count;
1818 }
1819 
1820 static void bus_reset_work(struct work_struct *work)
1821 {
1822 	struct fw_ohci *ohci =
1823 		container_of(work, struct fw_ohci, bus_reset_work);
1824 	int self_id_count, generation, new_generation, i, j;
1825 	u32 reg;
1826 	void *free_rom = NULL;
1827 	dma_addr_t free_rom_bus = 0;
1828 	bool is_new_root;
1829 
1830 	reg = reg_read(ohci, OHCI1394_NodeID);
1831 	if (!(reg & OHCI1394_NodeID_idValid)) {
1832 		dev_notice(ohci->card.device,
1833 			   "node ID not valid, new bus reset in progress\n");
1834 		return;
1835 	}
1836 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1837 		dev_notice(ohci->card.device, "malconfigured bus\n");
1838 		return;
1839 	}
1840 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1841 			       OHCI1394_NodeID_nodeNumber);
1842 
1843 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1844 	if (!(ohci->is_root && is_new_root))
1845 		reg_write(ohci, OHCI1394_LinkControlSet,
1846 			  OHCI1394_LinkControl_cycleMaster);
1847 	ohci->is_root = is_new_root;
1848 
1849 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1850 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1851 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1852 		return;
1853 	}
1854 	/*
1855 	 * The count in the SelfIDCount register is the number of
1856 	 * bytes in the self ID receive buffer.  Since we also receive
1857 	 * the inverted quadlets and a header quadlet, we shift one
1858 	 * bit extra to get the actual number of self IDs.
1859 	 */
1860 	self_id_count = (reg >> 3) & 0xff;
1861 
1862 	if (self_id_count > 252) {
1863 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1864 		return;
1865 	}
1866 
1867 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1868 	rmb();
1869 
1870 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1871 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1872 			/*
1873 			 * If the invalid data looks like a cycle start packet,
1874 			 * it's likely to be the result of the cycle master
1875 			 * having a wrong gap count.  In this case, the self IDs
1876 			 * so far are valid and should be processed so that the
1877 			 * bus manager can then correct the gap count.
1878 			 */
1879 			if (cond_le32_to_cpu(ohci->self_id_cpu[i])
1880 							== 0xffff008f) {
1881 				dev_notice(ohci->card.device,
1882 					   "ignoring spurious self IDs\n");
1883 				self_id_count = j;
1884 				break;
1885 			} else {
1886 				dev_notice(ohci->card.device,
1887 					   "inconsistent self IDs\n");
1888 				return;
1889 			}
1890 		}
1891 		ohci->self_id_buffer[j] =
1892 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1893 	}
1894 
1895 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
1896 		self_id_count = find_and_insert_self_id(ohci, self_id_count);
1897 		if (self_id_count < 0) {
1898 			dev_notice(ohci->card.device,
1899 				   "could not construct local self ID\n");
1900 			return;
1901 		}
1902 	}
1903 
1904 	if (self_id_count == 0) {
1905 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1906 		return;
1907 	}
1908 	rmb();
1909 
1910 	/*
1911 	 * Check the consistency of the self IDs we just read.  The
1912 	 * problem we face is that a new bus reset can start while we
1913 	 * read out the self IDs from the DMA buffer. If this happens,
1914 	 * the DMA buffer will be overwritten with new self IDs and we
1915 	 * will read out inconsistent data.  The OHCI specification
1916 	 * (section 11.2) recommends a technique similar to
1917 	 * linux/seqlock.h, where we remember the generation of the
1918 	 * self IDs in the buffer before reading them out and compare
1919 	 * it to the current generation after reading them out.  If
1920 	 * the two generations match we know we have a consistent set
1921 	 * of self IDs.
1922 	 */
1923 
1924 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1925 	if (new_generation != generation) {
1926 		dev_notice(ohci->card.device,
1927 			   "new bus reset, discarding self ids\n");
1928 		return;
1929 	}
1930 
1931 	/* FIXME: Document how the locking works. */
1932 	spin_lock_irq(&ohci->lock);
1933 
1934 	ohci->generation = -1; /* prevent AT packet queueing */
1935 	context_stop(&ohci->at_request_ctx);
1936 	context_stop(&ohci->at_response_ctx);
1937 
1938 	spin_unlock_irq(&ohci->lock);
1939 
1940 	/*
1941 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
1942 	 * packets in the AT queues and software needs to drain them.
1943 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
1944 	 */
1945 	at_context_flush(&ohci->at_request_ctx);
1946 	at_context_flush(&ohci->at_response_ctx);
1947 
1948 	spin_lock_irq(&ohci->lock);
1949 
1950 	ohci->generation = generation;
1951 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1952 
1953 	if (ohci->quirks & QUIRK_RESET_PACKET)
1954 		ohci->request_generation = generation;
1955 
1956 	/*
1957 	 * This next bit is unrelated to the AT context stuff but we
1958 	 * have to do it under the spinlock also.  If a new config rom
1959 	 * was set up before this reset, the old one is now no longer
1960 	 * in use and we can free it. Update the config rom pointers
1961 	 * to point to the current config rom and clear the
1962 	 * next_config_rom pointer so a new update can take place.
1963 	 */
1964 
1965 	if (ohci->next_config_rom != NULL) {
1966 		if (ohci->next_config_rom != ohci->config_rom) {
1967 			free_rom      = ohci->config_rom;
1968 			free_rom_bus  = ohci->config_rom_bus;
1969 		}
1970 		ohci->config_rom      = ohci->next_config_rom;
1971 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1972 		ohci->next_config_rom = NULL;
1973 
1974 		/*
1975 		 * Restore config_rom image and manually update
1976 		 * config_rom registers.  Writing the header quadlet
1977 		 * will indicate that the config rom is ready, so we
1978 		 * do that last.
1979 		 */
1980 		reg_write(ohci, OHCI1394_BusOptions,
1981 			  be32_to_cpu(ohci->config_rom[2]));
1982 		ohci->config_rom[0] = ohci->next_header;
1983 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1984 			  be32_to_cpu(ohci->next_header));
1985 	}
1986 
1987 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1988 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1989 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1990 #endif
1991 
1992 	spin_unlock_irq(&ohci->lock);
1993 
1994 	if (free_rom)
1995 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1996 				  free_rom, free_rom_bus);
1997 
1998 	log_selfids(ohci, generation, self_id_count);
1999 
2000 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2001 				 self_id_count, ohci->self_id_buffer,
2002 				 ohci->csr_state_setclear_abdicate);
2003 	ohci->csr_state_setclear_abdicate = false;
2004 }
2005 
2006 static irqreturn_t irq_handler(int irq, void *data)
2007 {
2008 	struct fw_ohci *ohci = data;
2009 	u32 event, iso_event;
2010 	int i;
2011 
2012 	event = reg_read(ohci, OHCI1394_IntEventClear);
2013 
2014 	if (!event || !~event)
2015 		return IRQ_NONE;
2016 
2017 	/*
2018 	 * busReset and postedWriteErr must not be cleared yet
2019 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2020 	 */
2021 	reg_write(ohci, OHCI1394_IntEventClear,
2022 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2023 	log_irqs(ohci, event);
2024 
2025 	if (event & OHCI1394_selfIDComplete)
2026 		queue_work(fw_workqueue, &ohci->bus_reset_work);
2027 
2028 	if (event & OHCI1394_RQPkt)
2029 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2030 
2031 	if (event & OHCI1394_RSPkt)
2032 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2033 
2034 	if (event & OHCI1394_reqTxComplete)
2035 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
2036 
2037 	if (event & OHCI1394_respTxComplete)
2038 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
2039 
2040 	if (event & OHCI1394_isochRx) {
2041 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2042 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2043 
2044 		while (iso_event) {
2045 			i = ffs(iso_event) - 1;
2046 			tasklet_schedule(
2047 				&ohci->ir_context_list[i].context.tasklet);
2048 			iso_event &= ~(1 << i);
2049 		}
2050 	}
2051 
2052 	if (event & OHCI1394_isochTx) {
2053 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2054 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2055 
2056 		while (iso_event) {
2057 			i = ffs(iso_event) - 1;
2058 			tasklet_schedule(
2059 				&ohci->it_context_list[i].context.tasklet);
2060 			iso_event &= ~(1 << i);
2061 		}
2062 	}
2063 
2064 	if (unlikely(event & OHCI1394_regAccessFail))
2065 		dev_err(ohci->card.device, "register access failure\n");
2066 
2067 	if (unlikely(event & OHCI1394_postedWriteErr)) {
2068 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2069 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2070 		reg_write(ohci, OHCI1394_IntEventClear,
2071 			  OHCI1394_postedWriteErr);
2072 		if (printk_ratelimit())
2073 			dev_err(ohci->card.device, "PCI posted write error\n");
2074 	}
2075 
2076 	if (unlikely(event & OHCI1394_cycleTooLong)) {
2077 		if (printk_ratelimit())
2078 			dev_notice(ohci->card.device,
2079 				   "isochronous cycle too long\n");
2080 		reg_write(ohci, OHCI1394_LinkControlSet,
2081 			  OHCI1394_LinkControl_cycleMaster);
2082 	}
2083 
2084 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
2085 		/*
2086 		 * We need to clear this event bit in order to make
2087 		 * cycleMatch isochronous I/O work.  In theory we should
2088 		 * stop active cycleMatch iso contexts now and restart
2089 		 * them at least two cycles later.  (FIXME?)
2090 		 */
2091 		if (printk_ratelimit())
2092 			dev_notice(ohci->card.device,
2093 				   "isochronous cycle inconsistent\n");
2094 	}
2095 
2096 	if (unlikely(event & OHCI1394_unrecoverableError))
2097 		handle_dead_contexts(ohci);
2098 
2099 	if (event & OHCI1394_cycle64Seconds) {
2100 		spin_lock(&ohci->lock);
2101 		update_bus_time(ohci);
2102 		spin_unlock(&ohci->lock);
2103 	} else
2104 		flush_writes(ohci);
2105 
2106 	return IRQ_HANDLED;
2107 }
2108 
2109 static int software_reset(struct fw_ohci *ohci)
2110 {
2111 	u32 val;
2112 	int i;
2113 
2114 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2115 	for (i = 0; i < 500; i++) {
2116 		val = reg_read(ohci, OHCI1394_HCControlSet);
2117 		if (!~val)
2118 			return -ENODEV; /* Card was ejected. */
2119 
2120 		if (!(val & OHCI1394_HCControl_softReset))
2121 			return 0;
2122 
2123 		msleep(1);
2124 	}
2125 
2126 	return -EBUSY;
2127 }
2128 
2129 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2130 {
2131 	size_t size = length * 4;
2132 
2133 	memcpy(dest, src, size);
2134 	if (size < CONFIG_ROM_SIZE)
2135 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2136 }
2137 
2138 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2139 {
2140 	bool enable_1394a;
2141 	int ret, clear, set, offset;
2142 
2143 	/* Check if the driver should configure link and PHY. */
2144 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2145 	      OHCI1394_HCControl_programPhyEnable))
2146 		return 0;
2147 
2148 	/* Paranoia: check whether the PHY supports 1394a, too. */
2149 	enable_1394a = false;
2150 	ret = read_phy_reg(ohci, 2);
2151 	if (ret < 0)
2152 		return ret;
2153 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2154 		ret = read_paged_phy_reg(ohci, 1, 8);
2155 		if (ret < 0)
2156 			return ret;
2157 		if (ret >= 1)
2158 			enable_1394a = true;
2159 	}
2160 
2161 	if (ohci->quirks & QUIRK_NO_1394A)
2162 		enable_1394a = false;
2163 
2164 	/* Configure PHY and link consistently. */
2165 	if (enable_1394a) {
2166 		clear = 0;
2167 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2168 	} else {
2169 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2170 		set = 0;
2171 	}
2172 	ret = update_phy_reg(ohci, 5, clear, set);
2173 	if (ret < 0)
2174 		return ret;
2175 
2176 	if (enable_1394a)
2177 		offset = OHCI1394_HCControlSet;
2178 	else
2179 		offset = OHCI1394_HCControlClear;
2180 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2181 
2182 	/* Clean up: configuration has been taken care of. */
2183 	reg_write(ohci, OHCI1394_HCControlClear,
2184 		  OHCI1394_HCControl_programPhyEnable);
2185 
2186 	return 0;
2187 }
2188 
2189 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2190 {
2191 	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2192 	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2193 	int reg, i;
2194 
2195 	reg = read_phy_reg(ohci, 2);
2196 	if (reg < 0)
2197 		return reg;
2198 	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2199 		return 0;
2200 
2201 	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2202 		reg = read_paged_phy_reg(ohci, 1, i + 10);
2203 		if (reg < 0)
2204 			return reg;
2205 		if (reg != id[i])
2206 			return 0;
2207 	}
2208 	return 1;
2209 }
2210 
2211 static int ohci_enable(struct fw_card *card,
2212 		       const __be32 *config_rom, size_t length)
2213 {
2214 	struct fw_ohci *ohci = fw_ohci(card);
2215 	struct pci_dev *dev = to_pci_dev(card->device);
2216 	u32 lps, seconds, version, irqs;
2217 	int i, ret;
2218 
2219 	if (software_reset(ohci)) {
2220 		dev_err(card->device, "failed to reset ohci card\n");
2221 		return -EBUSY;
2222 	}
2223 
2224 	/*
2225 	 * Now enable LPS, which we need in order to start accessing
2226 	 * most of the registers.  In fact, on some cards (ALI M5251),
2227 	 * accessing registers in the SClk domain without LPS enabled
2228 	 * will lock up the machine.  Wait 50msec to make sure we have
2229 	 * full link enabled.  However, with some cards (well, at least
2230 	 * a JMicron PCIe card), we have to try again sometimes.
2231 	 */
2232 	reg_write(ohci, OHCI1394_HCControlSet,
2233 		  OHCI1394_HCControl_LPS |
2234 		  OHCI1394_HCControl_postedWriteEnable);
2235 	flush_writes(ohci);
2236 
2237 	for (lps = 0, i = 0; !lps && i < 3; i++) {
2238 		msleep(50);
2239 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2240 		      OHCI1394_HCControl_LPS;
2241 	}
2242 
2243 	if (!lps) {
2244 		dev_err(card->device, "failed to set Link Power Status\n");
2245 		return -EIO;
2246 	}
2247 
2248 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2249 		ret = probe_tsb41ba3d(ohci);
2250 		if (ret < 0)
2251 			return ret;
2252 		if (ret)
2253 			dev_notice(card->device, "local TSB41BA3D phy\n");
2254 		else
2255 			ohci->quirks &= ~QUIRK_TI_SLLZ059;
2256 	}
2257 
2258 	reg_write(ohci, OHCI1394_HCControlClear,
2259 		  OHCI1394_HCControl_noByteSwapData);
2260 
2261 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2262 	reg_write(ohci, OHCI1394_LinkControlSet,
2263 		  OHCI1394_LinkControl_cycleTimerEnable |
2264 		  OHCI1394_LinkControl_cycleMaster);
2265 
2266 	reg_write(ohci, OHCI1394_ATRetries,
2267 		  OHCI1394_MAX_AT_REQ_RETRIES |
2268 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2269 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2270 		  (200 << 16));
2271 
2272 	seconds = lower_32_bits(get_seconds());
2273 	reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
2274 	ohci->bus_time = seconds & ~0x3f;
2275 
2276 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2277 	if (version >= OHCI_VERSION_1_1) {
2278 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2279 			  0xfffffffe);
2280 		card->broadcast_channel_auto_allocated = true;
2281 	}
2282 
2283 	/* Get implemented bits of the priority arbitration request counter. */
2284 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2285 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2286 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2287 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2288 
2289 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
2290 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2291 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2292 
2293 	ret = configure_1394a_enhancements(ohci);
2294 	if (ret < 0)
2295 		return ret;
2296 
2297 	/* Activate link_on bit and contender bit in our self ID packets.*/
2298 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2299 	if (ret < 0)
2300 		return ret;
2301 
2302 	/*
2303 	 * When the link is not yet enabled, the atomic config rom
2304 	 * update mechanism described below in ohci_set_config_rom()
2305 	 * is not active.  We have to update ConfigRomHeader and
2306 	 * BusOptions manually, and the write to ConfigROMmap takes
2307 	 * effect immediately.  We tie this to the enabling of the
2308 	 * link, so we have a valid config rom before enabling - the
2309 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2310 	 * values before enabling.
2311 	 *
2312 	 * However, when the ConfigROMmap is written, some controllers
2313 	 * always read back quadlets 0 and 2 from the config rom to
2314 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2315 	 * They shouldn't do that in this initial case where the link
2316 	 * isn't enabled.  This means we have to use the same
2317 	 * workaround here, setting the bus header to 0 and then write
2318 	 * the right values in the bus reset tasklet.
2319 	 */
2320 
2321 	if (config_rom) {
2322 		ohci->next_config_rom =
2323 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2324 					   &ohci->next_config_rom_bus,
2325 					   GFP_KERNEL);
2326 		if (ohci->next_config_rom == NULL)
2327 			return -ENOMEM;
2328 
2329 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2330 	} else {
2331 		/*
2332 		 * In the suspend case, config_rom is NULL, which
2333 		 * means that we just reuse the old config rom.
2334 		 */
2335 		ohci->next_config_rom = ohci->config_rom;
2336 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2337 	}
2338 
2339 	ohci->next_header = ohci->next_config_rom[0];
2340 	ohci->next_config_rom[0] = 0;
2341 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2342 	reg_write(ohci, OHCI1394_BusOptions,
2343 		  be32_to_cpu(ohci->next_config_rom[2]));
2344 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2345 
2346 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2347 
2348 	if (!(ohci->quirks & QUIRK_NO_MSI))
2349 		pci_enable_msi(dev);
2350 	if (request_irq(dev->irq, irq_handler,
2351 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
2352 			ohci_driver_name, ohci)) {
2353 		dev_err(card->device, "failed to allocate interrupt %d\n",
2354 			dev->irq);
2355 		pci_disable_msi(dev);
2356 
2357 		if (config_rom) {
2358 			dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2359 					  ohci->next_config_rom,
2360 					  ohci->next_config_rom_bus);
2361 			ohci->next_config_rom = NULL;
2362 		}
2363 		return -EIO;
2364 	}
2365 
2366 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2367 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2368 		OHCI1394_isochTx | OHCI1394_isochRx |
2369 		OHCI1394_postedWriteErr |
2370 		OHCI1394_selfIDComplete |
2371 		OHCI1394_regAccessFail |
2372 		OHCI1394_cycle64Seconds |
2373 		OHCI1394_cycleInconsistent |
2374 		OHCI1394_unrecoverableError |
2375 		OHCI1394_cycleTooLong |
2376 		OHCI1394_masterIntEnable;
2377 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2378 		irqs |= OHCI1394_busReset;
2379 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2380 
2381 	reg_write(ohci, OHCI1394_HCControlSet,
2382 		  OHCI1394_HCControl_linkEnable |
2383 		  OHCI1394_HCControl_BIBimageValid);
2384 
2385 	reg_write(ohci, OHCI1394_LinkControlSet,
2386 		  OHCI1394_LinkControl_rcvSelfID |
2387 		  OHCI1394_LinkControl_rcvPhyPkt);
2388 
2389 	ar_context_run(&ohci->ar_request_ctx);
2390 	ar_context_run(&ohci->ar_response_ctx);
2391 
2392 	flush_writes(ohci);
2393 
2394 	/* We are ready to go, reset bus to finish initialization. */
2395 	fw_schedule_bus_reset(&ohci->card, false, true);
2396 
2397 	return 0;
2398 }
2399 
2400 static int ohci_set_config_rom(struct fw_card *card,
2401 			       const __be32 *config_rom, size_t length)
2402 {
2403 	struct fw_ohci *ohci;
2404 	__be32 *next_config_rom;
2405 	dma_addr_t uninitialized_var(next_config_rom_bus);
2406 
2407 	ohci = fw_ohci(card);
2408 
2409 	/*
2410 	 * When the OHCI controller is enabled, the config rom update
2411 	 * mechanism is a bit tricky, but easy enough to use.  See
2412 	 * section 5.5.6 in the OHCI specification.
2413 	 *
2414 	 * The OHCI controller caches the new config rom address in a
2415 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2416 	 * for the changes to take place.  When the bus reset is
2417 	 * detected, the controller loads the new values for the
2418 	 * ConfigRomHeader and BusOptions registers from the specified
2419 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2420 	 * shadow register. All automatically and atomically.
2421 	 *
2422 	 * Now, there's a twist to this story.  The automatic load of
2423 	 * ConfigRomHeader and BusOptions doesn't honor the
2424 	 * noByteSwapData bit, so with a be32 config rom, the
2425 	 * controller will load be32 values in to these registers
2426 	 * during the atomic update, even on litte endian
2427 	 * architectures.  The workaround we use is to put a 0 in the
2428 	 * header quadlet; 0 is endian agnostic and means that the
2429 	 * config rom isn't ready yet.  In the bus reset tasklet we
2430 	 * then set up the real values for the two registers.
2431 	 *
2432 	 * We use ohci->lock to avoid racing with the code that sets
2433 	 * ohci->next_config_rom to NULL (see bus_reset_work).
2434 	 */
2435 
2436 	next_config_rom =
2437 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2438 				   &next_config_rom_bus, GFP_KERNEL);
2439 	if (next_config_rom == NULL)
2440 		return -ENOMEM;
2441 
2442 	spin_lock_irq(&ohci->lock);
2443 
2444 	/*
2445 	 * If there is not an already pending config_rom update,
2446 	 * push our new allocation into the ohci->next_config_rom
2447 	 * and then mark the local variable as null so that we
2448 	 * won't deallocate the new buffer.
2449 	 *
2450 	 * OTOH, if there is a pending config_rom update, just
2451 	 * use that buffer with the new config_rom data, and
2452 	 * let this routine free the unused DMA allocation.
2453 	 */
2454 
2455 	if (ohci->next_config_rom == NULL) {
2456 		ohci->next_config_rom = next_config_rom;
2457 		ohci->next_config_rom_bus = next_config_rom_bus;
2458 		next_config_rom = NULL;
2459 	}
2460 
2461 	copy_config_rom(ohci->next_config_rom, config_rom, length);
2462 
2463 	ohci->next_header = config_rom[0];
2464 	ohci->next_config_rom[0] = 0;
2465 
2466 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2467 
2468 	spin_unlock_irq(&ohci->lock);
2469 
2470 	/* If we didn't use the DMA allocation, delete it. */
2471 	if (next_config_rom != NULL)
2472 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2473 				  next_config_rom, next_config_rom_bus);
2474 
2475 	/*
2476 	 * Now initiate a bus reset to have the changes take
2477 	 * effect. We clean up the old config rom memory and DMA
2478 	 * mappings in the bus reset tasklet, since the OHCI
2479 	 * controller could need to access it before the bus reset
2480 	 * takes effect.
2481 	 */
2482 
2483 	fw_schedule_bus_reset(&ohci->card, true, true);
2484 
2485 	return 0;
2486 }
2487 
2488 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2489 {
2490 	struct fw_ohci *ohci = fw_ohci(card);
2491 
2492 	at_context_transmit(&ohci->at_request_ctx, packet);
2493 }
2494 
2495 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2496 {
2497 	struct fw_ohci *ohci = fw_ohci(card);
2498 
2499 	at_context_transmit(&ohci->at_response_ctx, packet);
2500 }
2501 
2502 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2503 {
2504 	struct fw_ohci *ohci = fw_ohci(card);
2505 	struct context *ctx = &ohci->at_request_ctx;
2506 	struct driver_data *driver_data = packet->driver_data;
2507 	int ret = -ENOENT;
2508 
2509 	tasklet_disable(&ctx->tasklet);
2510 
2511 	if (packet->ack != 0)
2512 		goto out;
2513 
2514 	if (packet->payload_mapped)
2515 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2516 				 packet->payload_length, DMA_TO_DEVICE);
2517 
2518 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2519 	driver_data->packet = NULL;
2520 	packet->ack = RCODE_CANCELLED;
2521 	packet->callback(packet, &ohci->card, packet->ack);
2522 	ret = 0;
2523  out:
2524 	tasklet_enable(&ctx->tasklet);
2525 
2526 	return ret;
2527 }
2528 
2529 static int ohci_enable_phys_dma(struct fw_card *card,
2530 				int node_id, int generation)
2531 {
2532 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2533 	return 0;
2534 #else
2535 	struct fw_ohci *ohci = fw_ohci(card);
2536 	unsigned long flags;
2537 	int n, ret = 0;
2538 
2539 	/*
2540 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2541 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2542 	 */
2543 
2544 	spin_lock_irqsave(&ohci->lock, flags);
2545 
2546 	if (ohci->generation != generation) {
2547 		ret = -ESTALE;
2548 		goto out;
2549 	}
2550 
2551 	/*
2552 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2553 	 * enabled for _all_ nodes on remote buses.
2554 	 */
2555 
2556 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2557 	if (n < 32)
2558 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2559 	else
2560 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2561 
2562 	flush_writes(ohci);
2563  out:
2564 	spin_unlock_irqrestore(&ohci->lock, flags);
2565 
2566 	return ret;
2567 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2568 }
2569 
2570 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2571 {
2572 	struct fw_ohci *ohci = fw_ohci(card);
2573 	unsigned long flags;
2574 	u32 value;
2575 
2576 	switch (csr_offset) {
2577 	case CSR_STATE_CLEAR:
2578 	case CSR_STATE_SET:
2579 		if (ohci->is_root &&
2580 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2581 		     OHCI1394_LinkControl_cycleMaster))
2582 			value = CSR_STATE_BIT_CMSTR;
2583 		else
2584 			value = 0;
2585 		if (ohci->csr_state_setclear_abdicate)
2586 			value |= CSR_STATE_BIT_ABDICATE;
2587 
2588 		return value;
2589 
2590 	case CSR_NODE_IDS:
2591 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2592 
2593 	case CSR_CYCLE_TIME:
2594 		return get_cycle_time(ohci);
2595 
2596 	case CSR_BUS_TIME:
2597 		/*
2598 		 * We might be called just after the cycle timer has wrapped
2599 		 * around but just before the cycle64Seconds handler, so we
2600 		 * better check here, too, if the bus time needs to be updated.
2601 		 */
2602 		spin_lock_irqsave(&ohci->lock, flags);
2603 		value = update_bus_time(ohci);
2604 		spin_unlock_irqrestore(&ohci->lock, flags);
2605 		return value;
2606 
2607 	case CSR_BUSY_TIMEOUT:
2608 		value = reg_read(ohci, OHCI1394_ATRetries);
2609 		return (value >> 4) & 0x0ffff00f;
2610 
2611 	case CSR_PRIORITY_BUDGET:
2612 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2613 			(ohci->pri_req_max << 8);
2614 
2615 	default:
2616 		WARN_ON(1);
2617 		return 0;
2618 	}
2619 }
2620 
2621 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2622 {
2623 	struct fw_ohci *ohci = fw_ohci(card);
2624 	unsigned long flags;
2625 
2626 	switch (csr_offset) {
2627 	case CSR_STATE_CLEAR:
2628 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2629 			reg_write(ohci, OHCI1394_LinkControlClear,
2630 				  OHCI1394_LinkControl_cycleMaster);
2631 			flush_writes(ohci);
2632 		}
2633 		if (value & CSR_STATE_BIT_ABDICATE)
2634 			ohci->csr_state_setclear_abdicate = false;
2635 		break;
2636 
2637 	case CSR_STATE_SET:
2638 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2639 			reg_write(ohci, OHCI1394_LinkControlSet,
2640 				  OHCI1394_LinkControl_cycleMaster);
2641 			flush_writes(ohci);
2642 		}
2643 		if (value & CSR_STATE_BIT_ABDICATE)
2644 			ohci->csr_state_setclear_abdicate = true;
2645 		break;
2646 
2647 	case CSR_NODE_IDS:
2648 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2649 		flush_writes(ohci);
2650 		break;
2651 
2652 	case CSR_CYCLE_TIME:
2653 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2654 		reg_write(ohci, OHCI1394_IntEventSet,
2655 			  OHCI1394_cycleInconsistent);
2656 		flush_writes(ohci);
2657 		break;
2658 
2659 	case CSR_BUS_TIME:
2660 		spin_lock_irqsave(&ohci->lock, flags);
2661 		ohci->bus_time = (ohci->bus_time & 0x7f) | (value & ~0x7f);
2662 		spin_unlock_irqrestore(&ohci->lock, flags);
2663 		break;
2664 
2665 	case CSR_BUSY_TIMEOUT:
2666 		value = (value & 0xf) | ((value & 0xf) << 4) |
2667 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2668 		reg_write(ohci, OHCI1394_ATRetries, value);
2669 		flush_writes(ohci);
2670 		break;
2671 
2672 	case CSR_PRIORITY_BUDGET:
2673 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2674 		flush_writes(ohci);
2675 		break;
2676 
2677 	default:
2678 		WARN_ON(1);
2679 		break;
2680 	}
2681 }
2682 
2683 static void flush_iso_completions(struct iso_context *ctx)
2684 {
2685 	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2686 			      ctx->header_length, ctx->header,
2687 			      ctx->base.callback_data);
2688 	ctx->header_length = 0;
2689 }
2690 
2691 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2692 {
2693 	u32 *ctx_hdr;
2694 
2695 	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE)
2696 		flush_iso_completions(ctx);
2697 
2698 	ctx_hdr = ctx->header + ctx->header_length;
2699 	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2700 
2701 	/*
2702 	 * The two iso header quadlets are byteswapped to little
2703 	 * endian by the controller, but we want to present them
2704 	 * as big endian for consistency with the bus endianness.
2705 	 */
2706 	if (ctx->base.header_size > 0)
2707 		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2708 	if (ctx->base.header_size > 4)
2709 		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2710 	if (ctx->base.header_size > 8)
2711 		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2712 	ctx->header_length += ctx->base.header_size;
2713 }
2714 
2715 static int handle_ir_packet_per_buffer(struct context *context,
2716 				       struct descriptor *d,
2717 				       struct descriptor *last)
2718 {
2719 	struct iso_context *ctx =
2720 		container_of(context, struct iso_context, context);
2721 	struct descriptor *pd;
2722 	u32 buffer_dma;
2723 
2724 	for (pd = d; pd <= last; pd++)
2725 		if (pd->transfer_status)
2726 			break;
2727 	if (pd > last)
2728 		/* Descriptor(s) not done yet, stop iteration */
2729 		return 0;
2730 
2731 	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2732 		d++;
2733 		buffer_dma = le32_to_cpu(d->data_address);
2734 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2735 					      buffer_dma & PAGE_MASK,
2736 					      buffer_dma & ~PAGE_MASK,
2737 					      le16_to_cpu(d->req_count),
2738 					      DMA_FROM_DEVICE);
2739 	}
2740 
2741 	copy_iso_headers(ctx, (u32 *) (last + 1));
2742 
2743 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2744 		flush_iso_completions(ctx);
2745 
2746 	return 1;
2747 }
2748 
2749 /* d == last because each descriptor block is only a single descriptor. */
2750 static int handle_ir_buffer_fill(struct context *context,
2751 				 struct descriptor *d,
2752 				 struct descriptor *last)
2753 {
2754 	struct iso_context *ctx =
2755 		container_of(context, struct iso_context, context);
2756 	unsigned int req_count, res_count, completed;
2757 	u32 buffer_dma;
2758 
2759 	req_count = le16_to_cpu(last->req_count);
2760 	res_count = le16_to_cpu(ACCESS_ONCE(last->res_count));
2761 	completed = req_count - res_count;
2762 	buffer_dma = le32_to_cpu(last->data_address);
2763 
2764 	if (completed > 0) {
2765 		ctx->mc_buffer_bus = buffer_dma;
2766 		ctx->mc_completed = completed;
2767 	}
2768 
2769 	if (res_count != 0)
2770 		/* Descriptor(s) not done yet, stop iteration */
2771 		return 0;
2772 
2773 	dma_sync_single_range_for_cpu(context->ohci->card.device,
2774 				      buffer_dma & PAGE_MASK,
2775 				      buffer_dma & ~PAGE_MASK,
2776 				      completed, DMA_FROM_DEVICE);
2777 
2778 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2779 		ctx->base.callback.mc(&ctx->base,
2780 				      buffer_dma + completed,
2781 				      ctx->base.callback_data);
2782 		ctx->mc_completed = 0;
2783 	}
2784 
2785 	return 1;
2786 }
2787 
2788 static void flush_ir_buffer_fill(struct iso_context *ctx)
2789 {
2790 	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
2791 				      ctx->mc_buffer_bus & PAGE_MASK,
2792 				      ctx->mc_buffer_bus & ~PAGE_MASK,
2793 				      ctx->mc_completed, DMA_FROM_DEVICE);
2794 
2795 	ctx->base.callback.mc(&ctx->base,
2796 			      ctx->mc_buffer_bus + ctx->mc_completed,
2797 			      ctx->base.callback_data);
2798 	ctx->mc_completed = 0;
2799 }
2800 
2801 static inline void sync_it_packet_for_cpu(struct context *context,
2802 					  struct descriptor *pd)
2803 {
2804 	__le16 control;
2805 	u32 buffer_dma;
2806 
2807 	/* only packets beginning with OUTPUT_MORE* have data buffers */
2808 	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2809 		return;
2810 
2811 	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
2812 	pd += 2;
2813 
2814 	/*
2815 	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
2816 	 * data buffer is in the context program's coherent page and must not
2817 	 * be synced.
2818 	 */
2819 	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
2820 	    (context->current_bus          & PAGE_MASK)) {
2821 		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2822 			return;
2823 		pd++;
2824 	}
2825 
2826 	do {
2827 		buffer_dma = le32_to_cpu(pd->data_address);
2828 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2829 					      buffer_dma & PAGE_MASK,
2830 					      buffer_dma & ~PAGE_MASK,
2831 					      le16_to_cpu(pd->req_count),
2832 					      DMA_TO_DEVICE);
2833 		control = pd->control;
2834 		pd++;
2835 	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
2836 }
2837 
2838 static int handle_it_packet(struct context *context,
2839 			    struct descriptor *d,
2840 			    struct descriptor *last)
2841 {
2842 	struct iso_context *ctx =
2843 		container_of(context, struct iso_context, context);
2844 	struct descriptor *pd;
2845 	__be32 *ctx_hdr;
2846 
2847 	for (pd = d; pd <= last; pd++)
2848 		if (pd->transfer_status)
2849 			break;
2850 	if (pd > last)
2851 		/* Descriptor(s) not done yet, stop iteration */
2852 		return 0;
2853 
2854 	sync_it_packet_for_cpu(context, d);
2855 
2856 	if (ctx->header_length + 4 > PAGE_SIZE)
2857 		flush_iso_completions(ctx);
2858 
2859 	ctx_hdr = ctx->header + ctx->header_length;
2860 	ctx->last_timestamp = le16_to_cpu(last->res_count);
2861 	/* Present this value as big-endian to match the receive code */
2862 	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
2863 			       le16_to_cpu(pd->res_count));
2864 	ctx->header_length += 4;
2865 
2866 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2867 		flush_iso_completions(ctx);
2868 
2869 	return 1;
2870 }
2871 
2872 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2873 {
2874 	u32 hi = channels >> 32, lo = channels;
2875 
2876 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2877 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2878 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2879 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2880 	mmiowb();
2881 	ohci->mc_channels = channels;
2882 }
2883 
2884 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2885 				int type, int channel, size_t header_size)
2886 {
2887 	struct fw_ohci *ohci = fw_ohci(card);
2888 	struct iso_context *uninitialized_var(ctx);
2889 	descriptor_callback_t uninitialized_var(callback);
2890 	u64 *uninitialized_var(channels);
2891 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2892 	int index, ret = -EBUSY;
2893 
2894 	spin_lock_irq(&ohci->lock);
2895 
2896 	switch (type) {
2897 	case FW_ISO_CONTEXT_TRANSMIT:
2898 		mask     = &ohci->it_context_mask;
2899 		callback = handle_it_packet;
2900 		index    = ffs(*mask) - 1;
2901 		if (index >= 0) {
2902 			*mask &= ~(1 << index);
2903 			regs = OHCI1394_IsoXmitContextBase(index);
2904 			ctx  = &ohci->it_context_list[index];
2905 		}
2906 		break;
2907 
2908 	case FW_ISO_CONTEXT_RECEIVE:
2909 		channels = &ohci->ir_context_channels;
2910 		mask     = &ohci->ir_context_mask;
2911 		callback = handle_ir_packet_per_buffer;
2912 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2913 		if (index >= 0) {
2914 			*channels &= ~(1ULL << channel);
2915 			*mask     &= ~(1 << index);
2916 			regs = OHCI1394_IsoRcvContextBase(index);
2917 			ctx  = &ohci->ir_context_list[index];
2918 		}
2919 		break;
2920 
2921 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2922 		mask     = &ohci->ir_context_mask;
2923 		callback = handle_ir_buffer_fill;
2924 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2925 		if (index >= 0) {
2926 			ohci->mc_allocated = true;
2927 			*mask &= ~(1 << index);
2928 			regs = OHCI1394_IsoRcvContextBase(index);
2929 			ctx  = &ohci->ir_context_list[index];
2930 		}
2931 		break;
2932 
2933 	default:
2934 		index = -1;
2935 		ret = -ENOSYS;
2936 	}
2937 
2938 	spin_unlock_irq(&ohci->lock);
2939 
2940 	if (index < 0)
2941 		return ERR_PTR(ret);
2942 
2943 	memset(ctx, 0, sizeof(*ctx));
2944 	ctx->header_length = 0;
2945 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2946 	if (ctx->header == NULL) {
2947 		ret = -ENOMEM;
2948 		goto out;
2949 	}
2950 	ret = context_init(&ctx->context, ohci, regs, callback);
2951 	if (ret < 0)
2952 		goto out_with_header;
2953 
2954 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
2955 		set_multichannel_mask(ohci, 0);
2956 		ctx->mc_completed = 0;
2957 	}
2958 
2959 	return &ctx->base;
2960 
2961  out_with_header:
2962 	free_page((unsigned long)ctx->header);
2963  out:
2964 	spin_lock_irq(&ohci->lock);
2965 
2966 	switch (type) {
2967 	case FW_ISO_CONTEXT_RECEIVE:
2968 		*channels |= 1ULL << channel;
2969 		break;
2970 
2971 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2972 		ohci->mc_allocated = false;
2973 		break;
2974 	}
2975 	*mask |= 1 << index;
2976 
2977 	spin_unlock_irq(&ohci->lock);
2978 
2979 	return ERR_PTR(ret);
2980 }
2981 
2982 static int ohci_start_iso(struct fw_iso_context *base,
2983 			  s32 cycle, u32 sync, u32 tags)
2984 {
2985 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2986 	struct fw_ohci *ohci = ctx->context.ohci;
2987 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2988 	int index;
2989 
2990 	/* the controller cannot start without any queued packets */
2991 	if (ctx->context.last->branch_address == 0)
2992 		return -ENODATA;
2993 
2994 	switch (ctx->base.type) {
2995 	case FW_ISO_CONTEXT_TRANSMIT:
2996 		index = ctx - ohci->it_context_list;
2997 		match = 0;
2998 		if (cycle >= 0)
2999 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3000 				(cycle & 0x7fff) << 16;
3001 
3002 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3003 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3004 		context_run(&ctx->context, match);
3005 		break;
3006 
3007 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3008 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3009 		/* fall through */
3010 	case FW_ISO_CONTEXT_RECEIVE:
3011 		index = ctx - ohci->ir_context_list;
3012 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
3013 		if (cycle >= 0) {
3014 			match |= (cycle & 0x07fff) << 12;
3015 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3016 		}
3017 
3018 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3019 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3020 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3021 		context_run(&ctx->context, control);
3022 
3023 		ctx->sync = sync;
3024 		ctx->tags = tags;
3025 
3026 		break;
3027 	}
3028 
3029 	return 0;
3030 }
3031 
3032 static int ohci_stop_iso(struct fw_iso_context *base)
3033 {
3034 	struct fw_ohci *ohci = fw_ohci(base->card);
3035 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3036 	int index;
3037 
3038 	switch (ctx->base.type) {
3039 	case FW_ISO_CONTEXT_TRANSMIT:
3040 		index = ctx - ohci->it_context_list;
3041 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3042 		break;
3043 
3044 	case FW_ISO_CONTEXT_RECEIVE:
3045 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3046 		index = ctx - ohci->ir_context_list;
3047 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3048 		break;
3049 	}
3050 	flush_writes(ohci);
3051 	context_stop(&ctx->context);
3052 	tasklet_kill(&ctx->context.tasklet);
3053 
3054 	return 0;
3055 }
3056 
3057 static void ohci_free_iso_context(struct fw_iso_context *base)
3058 {
3059 	struct fw_ohci *ohci = fw_ohci(base->card);
3060 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3061 	unsigned long flags;
3062 	int index;
3063 
3064 	ohci_stop_iso(base);
3065 	context_release(&ctx->context);
3066 	free_page((unsigned long)ctx->header);
3067 
3068 	spin_lock_irqsave(&ohci->lock, flags);
3069 
3070 	switch (base->type) {
3071 	case FW_ISO_CONTEXT_TRANSMIT:
3072 		index = ctx - ohci->it_context_list;
3073 		ohci->it_context_mask |= 1 << index;
3074 		break;
3075 
3076 	case FW_ISO_CONTEXT_RECEIVE:
3077 		index = ctx - ohci->ir_context_list;
3078 		ohci->ir_context_mask |= 1 << index;
3079 		ohci->ir_context_channels |= 1ULL << base->channel;
3080 		break;
3081 
3082 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3083 		index = ctx - ohci->ir_context_list;
3084 		ohci->ir_context_mask |= 1 << index;
3085 		ohci->ir_context_channels |= ohci->mc_channels;
3086 		ohci->mc_channels = 0;
3087 		ohci->mc_allocated = false;
3088 		break;
3089 	}
3090 
3091 	spin_unlock_irqrestore(&ohci->lock, flags);
3092 }
3093 
3094 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3095 {
3096 	struct fw_ohci *ohci = fw_ohci(base->card);
3097 	unsigned long flags;
3098 	int ret;
3099 
3100 	switch (base->type) {
3101 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3102 
3103 		spin_lock_irqsave(&ohci->lock, flags);
3104 
3105 		/* Don't allow multichannel to grab other contexts' channels. */
3106 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3107 			*channels = ohci->ir_context_channels;
3108 			ret = -EBUSY;
3109 		} else {
3110 			set_multichannel_mask(ohci, *channels);
3111 			ret = 0;
3112 		}
3113 
3114 		spin_unlock_irqrestore(&ohci->lock, flags);
3115 
3116 		break;
3117 	default:
3118 		ret = -EINVAL;
3119 	}
3120 
3121 	return ret;
3122 }
3123 
3124 #ifdef CONFIG_PM
3125 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3126 {
3127 	int i;
3128 	struct iso_context *ctx;
3129 
3130 	for (i = 0 ; i < ohci->n_ir ; i++) {
3131 		ctx = &ohci->ir_context_list[i];
3132 		if (ctx->context.running)
3133 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3134 	}
3135 
3136 	for (i = 0 ; i < ohci->n_it ; i++) {
3137 		ctx = &ohci->it_context_list[i];
3138 		if (ctx->context.running)
3139 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3140 	}
3141 }
3142 #endif
3143 
3144 static int queue_iso_transmit(struct iso_context *ctx,
3145 			      struct fw_iso_packet *packet,
3146 			      struct fw_iso_buffer *buffer,
3147 			      unsigned long payload)
3148 {
3149 	struct descriptor *d, *last, *pd;
3150 	struct fw_iso_packet *p;
3151 	__le32 *header;
3152 	dma_addr_t d_bus, page_bus;
3153 	u32 z, header_z, payload_z, irq;
3154 	u32 payload_index, payload_end_index, next_page_index;
3155 	int page, end_page, i, length, offset;
3156 
3157 	p = packet;
3158 	payload_index = payload;
3159 
3160 	if (p->skip)
3161 		z = 1;
3162 	else
3163 		z = 2;
3164 	if (p->header_length > 0)
3165 		z++;
3166 
3167 	/* Determine the first page the payload isn't contained in. */
3168 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3169 	if (p->payload_length > 0)
3170 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
3171 	else
3172 		payload_z = 0;
3173 
3174 	z += payload_z;
3175 
3176 	/* Get header size in number of descriptors. */
3177 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3178 
3179 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3180 	if (d == NULL)
3181 		return -ENOMEM;
3182 
3183 	if (!p->skip) {
3184 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3185 		d[0].req_count = cpu_to_le16(8);
3186 		/*
3187 		 * Link the skip address to this descriptor itself.  This causes
3188 		 * a context to skip a cycle whenever lost cycles or FIFO
3189 		 * overruns occur, without dropping the data.  The application
3190 		 * should then decide whether this is an error condition or not.
3191 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
3192 		 */
3193 		d[0].branch_address = cpu_to_le32(d_bus | z);
3194 
3195 		header = (__le32 *) &d[1];
3196 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
3197 					IT_HEADER_TAG(p->tag) |
3198 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
3199 					IT_HEADER_CHANNEL(ctx->base.channel) |
3200 					IT_HEADER_SPEED(ctx->base.speed));
3201 		header[1] =
3202 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
3203 							  p->payload_length));
3204 	}
3205 
3206 	if (p->header_length > 0) {
3207 		d[2].req_count    = cpu_to_le16(p->header_length);
3208 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3209 		memcpy(&d[z], p->header, p->header_length);
3210 	}
3211 
3212 	pd = d + z - payload_z;
3213 	payload_end_index = payload_index + p->payload_length;
3214 	for (i = 0; i < payload_z; i++) {
3215 		page               = payload_index >> PAGE_SHIFT;
3216 		offset             = payload_index & ~PAGE_MASK;
3217 		next_page_index    = (page + 1) << PAGE_SHIFT;
3218 		length             =
3219 			min(next_page_index, payload_end_index) - payload_index;
3220 		pd[i].req_count    = cpu_to_le16(length);
3221 
3222 		page_bus = page_private(buffer->pages[page]);
3223 		pd[i].data_address = cpu_to_le32(page_bus + offset);
3224 
3225 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3226 						 page_bus, offset, length,
3227 						 DMA_TO_DEVICE);
3228 
3229 		payload_index += length;
3230 	}
3231 
3232 	if (p->interrupt)
3233 		irq = DESCRIPTOR_IRQ_ALWAYS;
3234 	else
3235 		irq = DESCRIPTOR_NO_IRQ;
3236 
3237 	last = z == 2 ? d : d + z - 1;
3238 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3239 				     DESCRIPTOR_STATUS |
3240 				     DESCRIPTOR_BRANCH_ALWAYS |
3241 				     irq);
3242 
3243 	context_append(&ctx->context, d, z, header_z);
3244 
3245 	return 0;
3246 }
3247 
3248 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3249 				       struct fw_iso_packet *packet,
3250 				       struct fw_iso_buffer *buffer,
3251 				       unsigned long payload)
3252 {
3253 	struct device *device = ctx->context.ohci->card.device;
3254 	struct descriptor *d, *pd;
3255 	dma_addr_t d_bus, page_bus;
3256 	u32 z, header_z, rest;
3257 	int i, j, length;
3258 	int page, offset, packet_count, header_size, payload_per_buffer;
3259 
3260 	/*
3261 	 * The OHCI controller puts the isochronous header and trailer in the
3262 	 * buffer, so we need at least 8 bytes.
3263 	 */
3264 	packet_count = packet->header_length / ctx->base.header_size;
3265 	header_size  = max(ctx->base.header_size, (size_t)8);
3266 
3267 	/* Get header size in number of descriptors. */
3268 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3269 	page     = payload >> PAGE_SHIFT;
3270 	offset   = payload & ~PAGE_MASK;
3271 	payload_per_buffer = packet->payload_length / packet_count;
3272 
3273 	for (i = 0; i < packet_count; i++) {
3274 		/* d points to the header descriptor */
3275 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3276 		d = context_get_descriptors(&ctx->context,
3277 				z + header_z, &d_bus);
3278 		if (d == NULL)
3279 			return -ENOMEM;
3280 
3281 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3282 					      DESCRIPTOR_INPUT_MORE);
3283 		if (packet->skip && i == 0)
3284 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3285 		d->req_count    = cpu_to_le16(header_size);
3286 		d->res_count    = d->req_count;
3287 		d->transfer_status = 0;
3288 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3289 
3290 		rest = payload_per_buffer;
3291 		pd = d;
3292 		for (j = 1; j < z; j++) {
3293 			pd++;
3294 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3295 						  DESCRIPTOR_INPUT_MORE);
3296 
3297 			if (offset + rest < PAGE_SIZE)
3298 				length = rest;
3299 			else
3300 				length = PAGE_SIZE - offset;
3301 			pd->req_count = cpu_to_le16(length);
3302 			pd->res_count = pd->req_count;
3303 			pd->transfer_status = 0;
3304 
3305 			page_bus = page_private(buffer->pages[page]);
3306 			pd->data_address = cpu_to_le32(page_bus + offset);
3307 
3308 			dma_sync_single_range_for_device(device, page_bus,
3309 							 offset, length,
3310 							 DMA_FROM_DEVICE);
3311 
3312 			offset = (offset + length) & ~PAGE_MASK;
3313 			rest -= length;
3314 			if (offset == 0)
3315 				page++;
3316 		}
3317 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3318 					  DESCRIPTOR_INPUT_LAST |
3319 					  DESCRIPTOR_BRANCH_ALWAYS);
3320 		if (packet->interrupt && i == packet_count - 1)
3321 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3322 
3323 		context_append(&ctx->context, d, z, header_z);
3324 	}
3325 
3326 	return 0;
3327 }
3328 
3329 static int queue_iso_buffer_fill(struct iso_context *ctx,
3330 				 struct fw_iso_packet *packet,
3331 				 struct fw_iso_buffer *buffer,
3332 				 unsigned long payload)
3333 {
3334 	struct descriptor *d;
3335 	dma_addr_t d_bus, page_bus;
3336 	int page, offset, rest, z, i, length;
3337 
3338 	page   = payload >> PAGE_SHIFT;
3339 	offset = payload & ~PAGE_MASK;
3340 	rest   = packet->payload_length;
3341 
3342 	/* We need one descriptor for each page in the buffer. */
3343 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3344 
3345 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3346 		return -EFAULT;
3347 
3348 	for (i = 0; i < z; i++) {
3349 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3350 		if (d == NULL)
3351 			return -ENOMEM;
3352 
3353 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3354 					 DESCRIPTOR_BRANCH_ALWAYS);
3355 		if (packet->skip && i == 0)
3356 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3357 		if (packet->interrupt && i == z - 1)
3358 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3359 
3360 		if (offset + rest < PAGE_SIZE)
3361 			length = rest;
3362 		else
3363 			length = PAGE_SIZE - offset;
3364 		d->req_count = cpu_to_le16(length);
3365 		d->res_count = d->req_count;
3366 		d->transfer_status = 0;
3367 
3368 		page_bus = page_private(buffer->pages[page]);
3369 		d->data_address = cpu_to_le32(page_bus + offset);
3370 
3371 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3372 						 page_bus, offset, length,
3373 						 DMA_FROM_DEVICE);
3374 
3375 		rest -= length;
3376 		offset = 0;
3377 		page++;
3378 
3379 		context_append(&ctx->context, d, 1, 0);
3380 	}
3381 
3382 	return 0;
3383 }
3384 
3385 static int ohci_queue_iso(struct fw_iso_context *base,
3386 			  struct fw_iso_packet *packet,
3387 			  struct fw_iso_buffer *buffer,
3388 			  unsigned long payload)
3389 {
3390 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3391 	unsigned long flags;
3392 	int ret = -ENOSYS;
3393 
3394 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3395 	switch (base->type) {
3396 	case FW_ISO_CONTEXT_TRANSMIT:
3397 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
3398 		break;
3399 	case FW_ISO_CONTEXT_RECEIVE:
3400 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3401 		break;
3402 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3403 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3404 		break;
3405 	}
3406 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3407 
3408 	return ret;
3409 }
3410 
3411 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3412 {
3413 	struct context *ctx =
3414 			&container_of(base, struct iso_context, base)->context;
3415 
3416 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3417 }
3418 
3419 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3420 {
3421 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3422 	int ret = 0;
3423 
3424 	tasklet_disable(&ctx->context.tasklet);
3425 
3426 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3427 		context_tasklet((unsigned long)&ctx->context);
3428 
3429 		switch (base->type) {
3430 		case FW_ISO_CONTEXT_TRANSMIT:
3431 		case FW_ISO_CONTEXT_RECEIVE:
3432 			if (ctx->header_length != 0)
3433 				flush_iso_completions(ctx);
3434 			break;
3435 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3436 			if (ctx->mc_completed != 0)
3437 				flush_ir_buffer_fill(ctx);
3438 			break;
3439 		default:
3440 			ret = -ENOSYS;
3441 		}
3442 
3443 		clear_bit_unlock(0, &ctx->flushing_completions);
3444 		smp_mb__after_clear_bit();
3445 	}
3446 
3447 	tasklet_enable(&ctx->context.tasklet);
3448 
3449 	return ret;
3450 }
3451 
3452 static const struct fw_card_driver ohci_driver = {
3453 	.enable			= ohci_enable,
3454 	.read_phy_reg		= ohci_read_phy_reg,
3455 	.update_phy_reg		= ohci_update_phy_reg,
3456 	.set_config_rom		= ohci_set_config_rom,
3457 	.send_request		= ohci_send_request,
3458 	.send_response		= ohci_send_response,
3459 	.cancel_packet		= ohci_cancel_packet,
3460 	.enable_phys_dma	= ohci_enable_phys_dma,
3461 	.read_csr		= ohci_read_csr,
3462 	.write_csr		= ohci_write_csr,
3463 
3464 	.allocate_iso_context	= ohci_allocate_iso_context,
3465 	.free_iso_context	= ohci_free_iso_context,
3466 	.set_iso_channels	= ohci_set_iso_channels,
3467 	.queue_iso		= ohci_queue_iso,
3468 	.flush_queue_iso	= ohci_flush_queue_iso,
3469 	.flush_iso_completions	= ohci_flush_iso_completions,
3470 	.start_iso		= ohci_start_iso,
3471 	.stop_iso		= ohci_stop_iso,
3472 };
3473 
3474 #ifdef CONFIG_PPC_PMAC
3475 static void pmac_ohci_on(struct pci_dev *dev)
3476 {
3477 	if (machine_is(powermac)) {
3478 		struct device_node *ofn = pci_device_to_OF_node(dev);
3479 
3480 		if (ofn) {
3481 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3482 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3483 		}
3484 	}
3485 }
3486 
3487 static void pmac_ohci_off(struct pci_dev *dev)
3488 {
3489 	if (machine_is(powermac)) {
3490 		struct device_node *ofn = pci_device_to_OF_node(dev);
3491 
3492 		if (ofn) {
3493 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3494 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3495 		}
3496 	}
3497 }
3498 #else
3499 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3500 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3501 #endif /* CONFIG_PPC_PMAC */
3502 
3503 static int __devinit pci_probe(struct pci_dev *dev,
3504 			       const struct pci_device_id *ent)
3505 {
3506 	struct fw_ohci *ohci;
3507 	u32 bus_options, max_receive, link_speed, version;
3508 	u64 guid;
3509 	int i, err;
3510 	size_t size;
3511 
3512 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3513 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3514 		return -ENOSYS;
3515 	}
3516 
3517 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3518 	if (ohci == NULL) {
3519 		err = -ENOMEM;
3520 		goto fail;
3521 	}
3522 
3523 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3524 
3525 	pmac_ohci_on(dev);
3526 
3527 	err = pci_enable_device(dev);
3528 	if (err) {
3529 		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3530 		goto fail_free;
3531 	}
3532 
3533 	pci_set_master(dev);
3534 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3535 	pci_set_drvdata(dev, ohci);
3536 
3537 	spin_lock_init(&ohci->lock);
3538 	mutex_init(&ohci->phy_reg_mutex);
3539 
3540 	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3541 
3542 	err = pci_request_region(dev, 0, ohci_driver_name);
3543 	if (err) {
3544 		dev_err(&dev->dev, "MMIO resource unavailable\n");
3545 		goto fail_disable;
3546 	}
3547 
3548 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3549 	if (ohci->registers == NULL) {
3550 		dev_err(&dev->dev, "failed to remap registers\n");
3551 		err = -ENXIO;
3552 		goto fail_iomem;
3553 	}
3554 
3555 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3556 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3557 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3558 		     ohci_quirks[i].device == dev->device) &&
3559 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3560 		     ohci_quirks[i].revision >= dev->revision)) {
3561 			ohci->quirks = ohci_quirks[i].flags;
3562 			break;
3563 		}
3564 	if (param_quirks)
3565 		ohci->quirks = param_quirks;
3566 
3567 	/*
3568 	 * Because dma_alloc_coherent() allocates at least one page,
3569 	 * we save space by using a common buffer for the AR request/
3570 	 * response descriptors and the self IDs buffer.
3571 	 */
3572 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3573 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3574 	ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3575 					       PAGE_SIZE,
3576 					       &ohci->misc_buffer_bus,
3577 					       GFP_KERNEL);
3578 	if (!ohci->misc_buffer) {
3579 		err = -ENOMEM;
3580 		goto fail_iounmap;
3581 	}
3582 
3583 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3584 			      OHCI1394_AsReqRcvContextControlSet);
3585 	if (err < 0)
3586 		goto fail_misc_buf;
3587 
3588 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3589 			      OHCI1394_AsRspRcvContextControlSet);
3590 	if (err < 0)
3591 		goto fail_arreq_ctx;
3592 
3593 	err = context_init(&ohci->at_request_ctx, ohci,
3594 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3595 	if (err < 0)
3596 		goto fail_arrsp_ctx;
3597 
3598 	err = context_init(&ohci->at_response_ctx, ohci,
3599 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3600 	if (err < 0)
3601 		goto fail_atreq_ctx;
3602 
3603 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3604 	ohci->ir_context_channels = ~0ULL;
3605 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3606 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3607 	ohci->ir_context_mask = ohci->ir_context_support;
3608 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3609 	size = sizeof(struct iso_context) * ohci->n_ir;
3610 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3611 
3612 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3613 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3614 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3615 	ohci->it_context_mask = ohci->it_context_support;
3616 	ohci->n_it = hweight32(ohci->it_context_mask);
3617 	size = sizeof(struct iso_context) * ohci->n_it;
3618 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3619 
3620 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3621 		err = -ENOMEM;
3622 		goto fail_contexts;
3623 	}
3624 
3625 	ohci->self_id_cpu = ohci->misc_buffer     + PAGE_SIZE/2;
3626 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3627 
3628 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3629 	max_receive = (bus_options >> 12) & 0xf;
3630 	link_speed = bus_options & 0x7;
3631 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3632 		reg_read(ohci, OHCI1394_GUIDLo);
3633 
3634 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3635 	if (err)
3636 		goto fail_contexts;
3637 
3638 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3639 	dev_notice(&dev->dev,
3640 		  "added OHCI v%x.%x device as card %d, "
3641 		  "%d IR + %d IT contexts, quirks 0x%x\n",
3642 		  version >> 16, version & 0xff, ohci->card.index,
3643 		  ohci->n_ir, ohci->n_it, ohci->quirks);
3644 
3645 	return 0;
3646 
3647  fail_contexts:
3648 	kfree(ohci->ir_context_list);
3649 	kfree(ohci->it_context_list);
3650 	context_release(&ohci->at_response_ctx);
3651  fail_atreq_ctx:
3652 	context_release(&ohci->at_request_ctx);
3653  fail_arrsp_ctx:
3654 	ar_context_release(&ohci->ar_response_ctx);
3655  fail_arreq_ctx:
3656 	ar_context_release(&ohci->ar_request_ctx);
3657  fail_misc_buf:
3658 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3659 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3660  fail_iounmap:
3661 	pci_iounmap(dev, ohci->registers);
3662  fail_iomem:
3663 	pci_release_region(dev, 0);
3664  fail_disable:
3665 	pci_disable_device(dev);
3666  fail_free:
3667 	kfree(ohci);
3668 	pmac_ohci_off(dev);
3669  fail:
3670 	if (err == -ENOMEM)
3671 		dev_err(&dev->dev, "out of memory\n");
3672 
3673 	return err;
3674 }
3675 
3676 static void pci_remove(struct pci_dev *dev)
3677 {
3678 	struct fw_ohci *ohci;
3679 
3680 	ohci = pci_get_drvdata(dev);
3681 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3682 	flush_writes(ohci);
3683 	cancel_work_sync(&ohci->bus_reset_work);
3684 	fw_core_remove_card(&ohci->card);
3685 
3686 	/*
3687 	 * FIXME: Fail all pending packets here, now that the upper
3688 	 * layers can't queue any more.
3689 	 */
3690 
3691 	software_reset(ohci);
3692 	free_irq(dev->irq, ohci);
3693 
3694 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3695 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3696 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3697 	if (ohci->config_rom)
3698 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3699 				  ohci->config_rom, ohci->config_rom_bus);
3700 	ar_context_release(&ohci->ar_request_ctx);
3701 	ar_context_release(&ohci->ar_response_ctx);
3702 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3703 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3704 	context_release(&ohci->at_request_ctx);
3705 	context_release(&ohci->at_response_ctx);
3706 	kfree(ohci->it_context_list);
3707 	kfree(ohci->ir_context_list);
3708 	pci_disable_msi(dev);
3709 	pci_iounmap(dev, ohci->registers);
3710 	pci_release_region(dev, 0);
3711 	pci_disable_device(dev);
3712 	kfree(ohci);
3713 	pmac_ohci_off(dev);
3714 
3715 	dev_notice(&dev->dev, "removed fw-ohci device\n");
3716 }
3717 
3718 #ifdef CONFIG_PM
3719 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3720 {
3721 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3722 	int err;
3723 
3724 	software_reset(ohci);
3725 	free_irq(dev->irq, ohci);
3726 	pci_disable_msi(dev);
3727 	err = pci_save_state(dev);
3728 	if (err) {
3729 		dev_err(&dev->dev, "pci_save_state failed\n");
3730 		return err;
3731 	}
3732 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3733 	if (err)
3734 		dev_err(&dev->dev, "pci_set_power_state failed with %d\n", err);
3735 	pmac_ohci_off(dev);
3736 
3737 	return 0;
3738 }
3739 
3740 static int pci_resume(struct pci_dev *dev)
3741 {
3742 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3743 	int err;
3744 
3745 	pmac_ohci_on(dev);
3746 	pci_set_power_state(dev, PCI_D0);
3747 	pci_restore_state(dev);
3748 	err = pci_enable_device(dev);
3749 	if (err) {
3750 		dev_err(&dev->dev, "pci_enable_device failed\n");
3751 		return err;
3752 	}
3753 
3754 	/* Some systems don't setup GUID register on resume from ram  */
3755 	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3756 					!reg_read(ohci, OHCI1394_GUIDHi)) {
3757 		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3758 		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3759 	}
3760 
3761 	err = ohci_enable(&ohci->card, NULL, 0);
3762 	if (err)
3763 		return err;
3764 
3765 	ohci_resume_iso_dma(ohci);
3766 
3767 	return 0;
3768 }
3769 #endif
3770 
3771 static const struct pci_device_id pci_table[] = {
3772 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3773 	{ }
3774 };
3775 
3776 MODULE_DEVICE_TABLE(pci, pci_table);
3777 
3778 static struct pci_driver fw_ohci_pci_driver = {
3779 	.name		= ohci_driver_name,
3780 	.id_table	= pci_table,
3781 	.probe		= pci_probe,
3782 	.remove		= pci_remove,
3783 #ifdef CONFIG_PM
3784 	.resume		= pci_resume,
3785 	.suspend	= pci_suspend,
3786 #endif
3787 };
3788 
3789 module_pci_driver(fw_ohci_pci_driver);
3790 
3791 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3792 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3793 MODULE_LICENSE("GPL");
3794 
3795 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3796 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3797 MODULE_ALIAS("ohci1394");
3798 #endif
3799