xref: /linux/drivers/firewire/ohci.c (revision ec2212088c42ff7d1362629ec26dda4f3e8bdad3)
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 #include <asm/system.h>
50 
51 #ifdef CONFIG_PPC_PMAC
52 #include <asm/pmac_feature.h>
53 #endif
54 
55 #include "core.h"
56 #include "ohci.h"
57 
58 #define DESCRIPTOR_OUTPUT_MORE		0
59 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
60 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
61 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
62 #define DESCRIPTOR_STATUS		(1 << 11)
63 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
64 #define DESCRIPTOR_PING			(1 << 7)
65 #define DESCRIPTOR_YY			(1 << 6)
66 #define DESCRIPTOR_NO_IRQ		(0 << 4)
67 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
68 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
69 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
70 #define DESCRIPTOR_WAIT			(3 << 0)
71 
72 struct descriptor {
73 	__le16 req_count;
74 	__le16 control;
75 	__le32 data_address;
76 	__le32 branch_address;
77 	__le16 res_count;
78 	__le16 transfer_status;
79 } __attribute__((aligned(16)));
80 
81 #define CONTROL_SET(regs)	(regs)
82 #define CONTROL_CLEAR(regs)	((regs) + 4)
83 #define COMMAND_PTR(regs)	((regs) + 12)
84 #define CONTEXT_MATCH(regs)	((regs) + 16)
85 
86 #define AR_BUFFER_SIZE	(32*1024)
87 #define AR_BUFFERS_MIN	DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
88 /* we need at least two pages for proper list management */
89 #define AR_BUFFERS	(AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)
90 
91 #define MAX_ASYNC_PAYLOAD	4096
92 #define MAX_AR_PACKET_SIZE	(16 + MAX_ASYNC_PAYLOAD + 4)
93 #define AR_WRAPAROUND_PAGES	DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)
94 
95 struct ar_context {
96 	struct fw_ohci *ohci;
97 	struct page *pages[AR_BUFFERS];
98 	void *buffer;
99 	struct descriptor *descriptors;
100 	dma_addr_t descriptors_bus;
101 	void *pointer;
102 	unsigned int last_buffer_index;
103 	u32 regs;
104 	struct tasklet_struct tasklet;
105 };
106 
107 struct context;
108 
109 typedef int (*descriptor_callback_t)(struct context *ctx,
110 				     struct descriptor *d,
111 				     struct descriptor *last);
112 
113 /*
114  * A buffer that contains a block of DMA-able coherent memory used for
115  * storing a portion of a DMA descriptor program.
116  */
117 struct descriptor_buffer {
118 	struct list_head list;
119 	dma_addr_t buffer_bus;
120 	size_t buffer_size;
121 	size_t used;
122 	struct descriptor buffer[0];
123 };
124 
125 struct context {
126 	struct fw_ohci *ohci;
127 	u32 regs;
128 	int total_allocation;
129 	u32 current_bus;
130 	bool running;
131 	bool flushing;
132 
133 	/*
134 	 * List of page-sized buffers for storing DMA descriptors.
135 	 * Head of list contains buffers in use and tail of list contains
136 	 * free buffers.
137 	 */
138 	struct list_head buffer_list;
139 
140 	/*
141 	 * Pointer to a buffer inside buffer_list that contains the tail
142 	 * end of the current DMA program.
143 	 */
144 	struct descriptor_buffer *buffer_tail;
145 
146 	/*
147 	 * The descriptor containing the branch address of the first
148 	 * descriptor that has not yet been filled by the device.
149 	 */
150 	struct descriptor *last;
151 
152 	/*
153 	 * The last descriptor in the DMA program.  It contains the branch
154 	 * address that must be updated upon appending a new descriptor.
155 	 */
156 	struct descriptor *prev;
157 
158 	descriptor_callback_t callback;
159 
160 	struct tasklet_struct tasklet;
161 };
162 
163 #define IT_HEADER_SY(v)          ((v) <<  0)
164 #define IT_HEADER_TCODE(v)       ((v) <<  4)
165 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
166 #define IT_HEADER_TAG(v)         ((v) << 14)
167 #define IT_HEADER_SPEED(v)       ((v) << 16)
168 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
169 
170 struct iso_context {
171 	struct fw_iso_context base;
172 	struct context context;
173 	void *header;
174 	size_t header_length;
175 	unsigned long flushing_completions;
176 	u32 mc_buffer_bus;
177 	u16 mc_completed;
178 	u16 last_timestamp;
179 	u8 sync;
180 	u8 tags;
181 };
182 
183 #define CONFIG_ROM_SIZE 1024
184 
185 struct fw_ohci {
186 	struct fw_card card;
187 
188 	__iomem char *registers;
189 	int node_id;
190 	int generation;
191 	int request_generation;	/* for timestamping incoming requests */
192 	unsigned quirks;
193 	unsigned int pri_req_max;
194 	u32 bus_time;
195 	bool is_root;
196 	bool csr_state_setclear_abdicate;
197 	int n_ir;
198 	int n_it;
199 	/*
200 	 * Spinlock for accessing fw_ohci data.  Never call out of
201 	 * this driver with this lock held.
202 	 */
203 	spinlock_t lock;
204 
205 	struct mutex phy_reg_mutex;
206 
207 	void *misc_buffer;
208 	dma_addr_t misc_buffer_bus;
209 
210 	struct ar_context ar_request_ctx;
211 	struct ar_context ar_response_ctx;
212 	struct context at_request_ctx;
213 	struct context at_response_ctx;
214 
215 	u32 it_context_support;
216 	u32 it_context_mask;     /* unoccupied IT contexts */
217 	struct iso_context *it_context_list;
218 	u64 ir_context_channels; /* unoccupied channels */
219 	u32 ir_context_support;
220 	u32 ir_context_mask;     /* unoccupied IR contexts */
221 	struct iso_context *ir_context_list;
222 	u64 mc_channels; /* channels in use by the multichannel IR context */
223 	bool mc_allocated;
224 
225 	__be32    *config_rom;
226 	dma_addr_t config_rom_bus;
227 	__be32    *next_config_rom;
228 	dma_addr_t next_config_rom_bus;
229 	__be32     next_header;
230 
231 	__le32    *self_id_cpu;
232 	dma_addr_t self_id_bus;
233 	struct work_struct bus_reset_work;
234 
235 	u32 self_id_buffer[512];
236 };
237 
238 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
239 {
240 	return container_of(card, struct fw_ohci, card);
241 }
242 
243 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
244 #define IR_CONTEXT_BUFFER_FILL		0x80000000
245 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
246 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
247 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
248 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
249 
250 #define CONTEXT_RUN	0x8000
251 #define CONTEXT_WAKE	0x1000
252 #define CONTEXT_DEAD	0x0800
253 #define CONTEXT_ACTIVE	0x0400
254 
255 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
256 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
257 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
258 
259 #define OHCI1394_REGISTER_SIZE		0x800
260 #define OHCI1394_PCI_HCI_Control	0x40
261 #define SELF_ID_BUF_SIZE		0x800
262 #define OHCI_TCODE_PHY_PACKET		0x0e
263 #define OHCI_VERSION_1_1		0x010010
264 
265 static char ohci_driver_name[] = KBUILD_MODNAME;
266 
267 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
268 #define PCI_DEVICE_ID_CREATIVE_SB1394	0x4001
269 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
270 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
271 #define PCI_DEVICE_ID_TI_TSB12LV26	0x8020
272 #define PCI_DEVICE_ID_TI_TSB82AA2	0x8025
273 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
274 
275 #define QUIRK_CYCLE_TIMER		1
276 #define QUIRK_RESET_PACKET		2
277 #define QUIRK_BE_HEADERS		4
278 #define QUIRK_NO_1394A			8
279 #define QUIRK_NO_MSI			16
280 #define QUIRK_TI_SLLZ059		32
281 
282 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
283 static const struct {
284 	unsigned short vendor, device, revision, flags;
285 } ohci_quirks[] = {
286 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
287 		QUIRK_CYCLE_TIMER},
288 
289 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
290 		QUIRK_BE_HEADERS},
291 
292 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
293 		QUIRK_NO_MSI},
294 
295 	{PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
296 		QUIRK_RESET_PACKET},
297 
298 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
299 		QUIRK_NO_MSI},
300 
301 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
302 		QUIRK_CYCLE_TIMER},
303 
304 	{PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
305 		QUIRK_NO_MSI},
306 
307 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
308 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
309 
310 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
311 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
312 
313 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
314 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
315 
316 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
317 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
318 
319 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
320 		QUIRK_RESET_PACKET},
321 
322 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
323 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
324 };
325 
326 /* This overrides anything that was found in ohci_quirks[]. */
327 static int param_quirks;
328 module_param_named(quirks, param_quirks, int, 0644);
329 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
330 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
331 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
332 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
333 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
334 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
335 	", TI SLLZ059 erratum = "	__stringify(QUIRK_TI_SLLZ059)
336 	")");
337 
338 #define OHCI_PARAM_DEBUG_AT_AR		1
339 #define OHCI_PARAM_DEBUG_SELFIDS	2
340 #define OHCI_PARAM_DEBUG_IRQS		4
341 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
342 
343 static int param_debug;
344 module_param_named(debug, param_debug, int, 0644);
345 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
346 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
347 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
348 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
349 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
350 	", or a combination, or all = -1)");
351 
352 static void log_irqs(struct fw_ohci *ohci, u32 evt)
353 {
354 	if (likely(!(param_debug &
355 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
356 		return;
357 
358 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
359 	    !(evt & OHCI1394_busReset))
360 		return;
361 
362 	dev_notice(ohci->card.device,
363 	    "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
364 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
365 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
366 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
367 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
368 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
369 	    evt & OHCI1394_isochRx		? " IR"			: "",
370 	    evt & OHCI1394_isochTx		? " IT"			: "",
371 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
372 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
373 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
374 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
375 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
376 	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
377 	    evt & OHCI1394_busReset		? " busReset"		: "",
378 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
379 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
380 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
381 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
382 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
383 		    OHCI1394_cycleInconsistent |
384 		    OHCI1394_regAccessFail | OHCI1394_busReset)
385 						? " ?"			: "");
386 }
387 
388 static const char *speed[] = {
389 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
390 };
391 static const char *power[] = {
392 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
393 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
394 };
395 static const char port[] = { '.', '-', 'p', 'c', };
396 
397 static char _p(u32 *s, int shift)
398 {
399 	return port[*s >> shift & 3];
400 }
401 
402 static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
403 {
404 	u32 *s;
405 
406 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
407 		return;
408 
409 	dev_notice(ohci->card.device,
410 		   "%d selfIDs, generation %d, local node ID %04x\n",
411 		   self_id_count, generation, ohci->node_id);
412 
413 	for (s = ohci->self_id_buffer; self_id_count--; ++s)
414 		if ((*s & 1 << 23) == 0)
415 			dev_notice(ohci->card.device,
416 			    "selfID 0: %08x, phy %d [%c%c%c] "
417 			    "%s gc=%d %s %s%s%s\n",
418 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
419 			    speed[*s >> 14 & 3], *s >> 16 & 63,
420 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
421 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
422 		else
423 			dev_notice(ohci->card.device,
424 			    "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
425 			    *s, *s >> 24 & 63,
426 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
427 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
428 }
429 
430 static const char *evts[] = {
431 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
432 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
433 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
434 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
435 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
436 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
437 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
438 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
439 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
440 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
441 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
442 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
443 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
444 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
445 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
446 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
447 	[0x20] = "pending/cancelled",
448 };
449 static const char *tcodes[] = {
450 	[0x0] = "QW req",		[0x1] = "BW req",
451 	[0x2] = "W resp",		[0x3] = "-reserved-",
452 	[0x4] = "QR req",		[0x5] = "BR req",
453 	[0x6] = "QR resp",		[0x7] = "BR resp",
454 	[0x8] = "cycle start",		[0x9] = "Lk req",
455 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
456 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
457 	[0xe] = "link internal",	[0xf] = "-reserved-",
458 };
459 
460 static void log_ar_at_event(struct fw_ohci *ohci,
461 			    char dir, int speed, u32 *header, int evt)
462 {
463 	int tcode = header[0] >> 4 & 0xf;
464 	char specific[12];
465 
466 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
467 		return;
468 
469 	if (unlikely(evt >= ARRAY_SIZE(evts)))
470 			evt = 0x1f;
471 
472 	if (evt == OHCI1394_evt_bus_reset) {
473 		dev_notice(ohci->card.device,
474 			   "A%c evt_bus_reset, generation %d\n",
475 			   dir, (header[2] >> 16) & 0xff);
476 		return;
477 	}
478 
479 	switch (tcode) {
480 	case 0x0: case 0x6: case 0x8:
481 		snprintf(specific, sizeof(specific), " = %08x",
482 			 be32_to_cpu((__force __be32)header[3]));
483 		break;
484 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
485 		snprintf(specific, sizeof(specific), " %x,%x",
486 			 header[3] >> 16, header[3] & 0xffff);
487 		break;
488 	default:
489 		specific[0] = '\0';
490 	}
491 
492 	switch (tcode) {
493 	case 0xa:
494 		dev_notice(ohci->card.device,
495 			   "A%c %s, %s\n",
496 			   dir, evts[evt], tcodes[tcode]);
497 		break;
498 	case 0xe:
499 		dev_notice(ohci->card.device,
500 			   "A%c %s, PHY %08x %08x\n",
501 			   dir, evts[evt], header[1], header[2]);
502 		break;
503 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
504 		dev_notice(ohci->card.device,
505 			   "A%c spd %x tl %02x, "
506 			   "%04x -> %04x, %s, "
507 			   "%s, %04x%08x%s\n",
508 			   dir, speed, header[0] >> 10 & 0x3f,
509 			   header[1] >> 16, header[0] >> 16, evts[evt],
510 			   tcodes[tcode], header[1] & 0xffff, header[2], specific);
511 		break;
512 	default:
513 		dev_notice(ohci->card.device,
514 			   "A%c spd %x tl %02x, "
515 			   "%04x -> %04x, %s, "
516 			   "%s%s\n",
517 			   dir, speed, header[0] >> 10 & 0x3f,
518 			   header[1] >> 16, header[0] >> 16, evts[evt],
519 			   tcodes[tcode], specific);
520 	}
521 }
522 
523 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
524 {
525 	writel(data, ohci->registers + offset);
526 }
527 
528 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
529 {
530 	return readl(ohci->registers + offset);
531 }
532 
533 static inline void flush_writes(const struct fw_ohci *ohci)
534 {
535 	/* Do a dummy read to flush writes. */
536 	reg_read(ohci, OHCI1394_Version);
537 }
538 
539 /*
540  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
541  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
542  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
543  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
544  */
545 static int read_phy_reg(struct fw_ohci *ohci, int addr)
546 {
547 	u32 val;
548 	int i;
549 
550 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
551 	for (i = 0; i < 3 + 100; i++) {
552 		val = reg_read(ohci, OHCI1394_PhyControl);
553 		if (!~val)
554 			return -ENODEV; /* Card was ejected. */
555 
556 		if (val & OHCI1394_PhyControl_ReadDone)
557 			return OHCI1394_PhyControl_ReadData(val);
558 
559 		/*
560 		 * Try a few times without waiting.  Sleeping is necessary
561 		 * only when the link/PHY interface is busy.
562 		 */
563 		if (i >= 3)
564 			msleep(1);
565 	}
566 	dev_err(ohci->card.device, "failed to read phy reg\n");
567 
568 	return -EBUSY;
569 }
570 
571 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
572 {
573 	int i;
574 
575 	reg_write(ohci, OHCI1394_PhyControl,
576 		  OHCI1394_PhyControl_Write(addr, val));
577 	for (i = 0; i < 3 + 100; i++) {
578 		val = reg_read(ohci, OHCI1394_PhyControl);
579 		if (!~val)
580 			return -ENODEV; /* Card was ejected. */
581 
582 		if (!(val & OHCI1394_PhyControl_WritePending))
583 			return 0;
584 
585 		if (i >= 3)
586 			msleep(1);
587 	}
588 	dev_err(ohci->card.device, "failed to write phy reg\n");
589 
590 	return -EBUSY;
591 }
592 
593 static int update_phy_reg(struct fw_ohci *ohci, int addr,
594 			  int clear_bits, int set_bits)
595 {
596 	int ret = read_phy_reg(ohci, addr);
597 	if (ret < 0)
598 		return ret;
599 
600 	/*
601 	 * The interrupt status bits are cleared by writing a one bit.
602 	 * Avoid clearing them unless explicitly requested in set_bits.
603 	 */
604 	if (addr == 5)
605 		clear_bits |= PHY_INT_STATUS_BITS;
606 
607 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
608 }
609 
610 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
611 {
612 	int ret;
613 
614 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
615 	if (ret < 0)
616 		return ret;
617 
618 	return read_phy_reg(ohci, addr);
619 }
620 
621 static int ohci_read_phy_reg(struct fw_card *card, int addr)
622 {
623 	struct fw_ohci *ohci = fw_ohci(card);
624 	int ret;
625 
626 	mutex_lock(&ohci->phy_reg_mutex);
627 	ret = read_phy_reg(ohci, addr);
628 	mutex_unlock(&ohci->phy_reg_mutex);
629 
630 	return ret;
631 }
632 
633 static int ohci_update_phy_reg(struct fw_card *card, int addr,
634 			       int clear_bits, int set_bits)
635 {
636 	struct fw_ohci *ohci = fw_ohci(card);
637 	int ret;
638 
639 	mutex_lock(&ohci->phy_reg_mutex);
640 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
641 	mutex_unlock(&ohci->phy_reg_mutex);
642 
643 	return ret;
644 }
645 
646 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
647 {
648 	return page_private(ctx->pages[i]);
649 }
650 
651 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
652 {
653 	struct descriptor *d;
654 
655 	d = &ctx->descriptors[index];
656 	d->branch_address  &= cpu_to_le32(~0xf);
657 	d->res_count       =  cpu_to_le16(PAGE_SIZE);
658 	d->transfer_status =  0;
659 
660 	wmb(); /* finish init of new descriptors before branch_address update */
661 	d = &ctx->descriptors[ctx->last_buffer_index];
662 	d->branch_address  |= cpu_to_le32(1);
663 
664 	ctx->last_buffer_index = index;
665 
666 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
667 }
668 
669 static void ar_context_release(struct ar_context *ctx)
670 {
671 	unsigned int i;
672 
673 	if (ctx->buffer)
674 		vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
675 
676 	for (i = 0; i < AR_BUFFERS; i++)
677 		if (ctx->pages[i]) {
678 			dma_unmap_page(ctx->ohci->card.device,
679 				       ar_buffer_bus(ctx, i),
680 				       PAGE_SIZE, DMA_FROM_DEVICE);
681 			__free_page(ctx->pages[i]);
682 		}
683 }
684 
685 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
686 {
687 	struct fw_ohci *ohci = ctx->ohci;
688 
689 	if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
690 		reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
691 		flush_writes(ohci);
692 
693 		dev_err(ohci->card.device, "AR error: %s; DMA stopped\n",
694 			error_msg);
695 	}
696 	/* FIXME: restart? */
697 }
698 
699 static inline unsigned int ar_next_buffer_index(unsigned int index)
700 {
701 	return (index + 1) % AR_BUFFERS;
702 }
703 
704 static inline unsigned int ar_prev_buffer_index(unsigned int index)
705 {
706 	return (index - 1 + AR_BUFFERS) % AR_BUFFERS;
707 }
708 
709 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
710 {
711 	return ar_next_buffer_index(ctx->last_buffer_index);
712 }
713 
714 /*
715  * We search for the buffer that contains the last AR packet DMA data written
716  * by the controller.
717  */
718 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
719 						 unsigned int *buffer_offset)
720 {
721 	unsigned int i, next_i, last = ctx->last_buffer_index;
722 	__le16 res_count, next_res_count;
723 
724 	i = ar_first_buffer_index(ctx);
725 	res_count = ACCESS_ONCE(ctx->descriptors[i].res_count);
726 
727 	/* A buffer that is not yet completely filled must be the last one. */
728 	while (i != last && res_count == 0) {
729 
730 		/* Peek at the next descriptor. */
731 		next_i = ar_next_buffer_index(i);
732 		rmb(); /* read descriptors in order */
733 		next_res_count = ACCESS_ONCE(
734 				ctx->descriptors[next_i].res_count);
735 		/*
736 		 * If the next descriptor is still empty, we must stop at this
737 		 * descriptor.
738 		 */
739 		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
740 			/*
741 			 * The exception is when the DMA data for one packet is
742 			 * split over three buffers; in this case, the middle
743 			 * buffer's descriptor might be never updated by the
744 			 * controller and look still empty, and we have to peek
745 			 * at the third one.
746 			 */
747 			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
748 				next_i = ar_next_buffer_index(next_i);
749 				rmb();
750 				next_res_count = ACCESS_ONCE(
751 					ctx->descriptors[next_i].res_count);
752 				if (next_res_count != cpu_to_le16(PAGE_SIZE))
753 					goto next_buffer_is_active;
754 			}
755 
756 			break;
757 		}
758 
759 next_buffer_is_active:
760 		i = next_i;
761 		res_count = next_res_count;
762 	}
763 
764 	rmb(); /* read res_count before the DMA data */
765 
766 	*buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
767 	if (*buffer_offset > PAGE_SIZE) {
768 		*buffer_offset = 0;
769 		ar_context_abort(ctx, "corrupted descriptor");
770 	}
771 
772 	return i;
773 }
774 
775 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
776 				    unsigned int end_buffer_index,
777 				    unsigned int end_buffer_offset)
778 {
779 	unsigned int i;
780 
781 	i = ar_first_buffer_index(ctx);
782 	while (i != end_buffer_index) {
783 		dma_sync_single_for_cpu(ctx->ohci->card.device,
784 					ar_buffer_bus(ctx, i),
785 					PAGE_SIZE, DMA_FROM_DEVICE);
786 		i = ar_next_buffer_index(i);
787 	}
788 	if (end_buffer_offset > 0)
789 		dma_sync_single_for_cpu(ctx->ohci->card.device,
790 					ar_buffer_bus(ctx, i),
791 					end_buffer_offset, DMA_FROM_DEVICE);
792 }
793 
794 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
795 #define cond_le32_to_cpu(v) \
796 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
797 #else
798 #define cond_le32_to_cpu(v) le32_to_cpu(v)
799 #endif
800 
801 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
802 {
803 	struct fw_ohci *ohci = ctx->ohci;
804 	struct fw_packet p;
805 	u32 status, length, tcode;
806 	int evt;
807 
808 	p.header[0] = cond_le32_to_cpu(buffer[0]);
809 	p.header[1] = cond_le32_to_cpu(buffer[1]);
810 	p.header[2] = cond_le32_to_cpu(buffer[2]);
811 
812 	tcode = (p.header[0] >> 4) & 0x0f;
813 	switch (tcode) {
814 	case TCODE_WRITE_QUADLET_REQUEST:
815 	case TCODE_READ_QUADLET_RESPONSE:
816 		p.header[3] = (__force __u32) buffer[3];
817 		p.header_length = 16;
818 		p.payload_length = 0;
819 		break;
820 
821 	case TCODE_READ_BLOCK_REQUEST :
822 		p.header[3] = cond_le32_to_cpu(buffer[3]);
823 		p.header_length = 16;
824 		p.payload_length = 0;
825 		break;
826 
827 	case TCODE_WRITE_BLOCK_REQUEST:
828 	case TCODE_READ_BLOCK_RESPONSE:
829 	case TCODE_LOCK_REQUEST:
830 	case TCODE_LOCK_RESPONSE:
831 		p.header[3] = cond_le32_to_cpu(buffer[3]);
832 		p.header_length = 16;
833 		p.payload_length = p.header[3] >> 16;
834 		if (p.payload_length > MAX_ASYNC_PAYLOAD) {
835 			ar_context_abort(ctx, "invalid packet length");
836 			return NULL;
837 		}
838 		break;
839 
840 	case TCODE_WRITE_RESPONSE:
841 	case TCODE_READ_QUADLET_REQUEST:
842 	case OHCI_TCODE_PHY_PACKET:
843 		p.header_length = 12;
844 		p.payload_length = 0;
845 		break;
846 
847 	default:
848 		ar_context_abort(ctx, "invalid tcode");
849 		return NULL;
850 	}
851 
852 	p.payload = (void *) buffer + p.header_length;
853 
854 	/* FIXME: What to do about evt_* errors? */
855 	length = (p.header_length + p.payload_length + 3) / 4;
856 	status = cond_le32_to_cpu(buffer[length]);
857 	evt    = (status >> 16) & 0x1f;
858 
859 	p.ack        = evt - 16;
860 	p.speed      = (status >> 21) & 0x7;
861 	p.timestamp  = status & 0xffff;
862 	p.generation = ohci->request_generation;
863 
864 	log_ar_at_event(ohci, 'R', p.speed, p.header, evt);
865 
866 	/*
867 	 * Several controllers, notably from NEC and VIA, forget to
868 	 * write ack_complete status at PHY packet reception.
869 	 */
870 	if (evt == OHCI1394_evt_no_status &&
871 	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
872 		p.ack = ACK_COMPLETE;
873 
874 	/*
875 	 * The OHCI bus reset handler synthesizes a PHY packet with
876 	 * the new generation number when a bus reset happens (see
877 	 * section 8.4.2.3).  This helps us determine when a request
878 	 * was received and make sure we send the response in the same
879 	 * generation.  We only need this for requests; for responses
880 	 * we use the unique tlabel for finding the matching
881 	 * request.
882 	 *
883 	 * Alas some chips sometimes emit bus reset packets with a
884 	 * wrong generation.  We set the correct generation for these
885 	 * at a slightly incorrect time (in bus_reset_work).
886 	 */
887 	if (evt == OHCI1394_evt_bus_reset) {
888 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
889 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
890 	} else if (ctx == &ohci->ar_request_ctx) {
891 		fw_core_handle_request(&ohci->card, &p);
892 	} else {
893 		fw_core_handle_response(&ohci->card, &p);
894 	}
895 
896 	return buffer + length + 1;
897 }
898 
899 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
900 {
901 	void *next;
902 
903 	while (p < end) {
904 		next = handle_ar_packet(ctx, p);
905 		if (!next)
906 			return p;
907 		p = next;
908 	}
909 
910 	return p;
911 }
912 
913 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
914 {
915 	unsigned int i;
916 
917 	i = ar_first_buffer_index(ctx);
918 	while (i != end_buffer) {
919 		dma_sync_single_for_device(ctx->ohci->card.device,
920 					   ar_buffer_bus(ctx, i),
921 					   PAGE_SIZE, DMA_FROM_DEVICE);
922 		ar_context_link_page(ctx, i);
923 		i = ar_next_buffer_index(i);
924 	}
925 }
926 
927 static void ar_context_tasklet(unsigned long data)
928 {
929 	struct ar_context *ctx = (struct ar_context *)data;
930 	unsigned int end_buffer_index, end_buffer_offset;
931 	void *p, *end;
932 
933 	p = ctx->pointer;
934 	if (!p)
935 		return;
936 
937 	end_buffer_index = ar_search_last_active_buffer(ctx,
938 							&end_buffer_offset);
939 	ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
940 	end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
941 
942 	if (end_buffer_index < ar_first_buffer_index(ctx)) {
943 		/*
944 		 * The filled part of the overall buffer wraps around; handle
945 		 * all packets up to the buffer end here.  If the last packet
946 		 * wraps around, its tail will be visible after the buffer end
947 		 * because the buffer start pages are mapped there again.
948 		 */
949 		void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
950 		p = handle_ar_packets(ctx, p, buffer_end);
951 		if (p < buffer_end)
952 			goto error;
953 		/* adjust p to point back into the actual buffer */
954 		p -= AR_BUFFERS * PAGE_SIZE;
955 	}
956 
957 	p = handle_ar_packets(ctx, p, end);
958 	if (p != end) {
959 		if (p > end)
960 			ar_context_abort(ctx, "inconsistent descriptor");
961 		goto error;
962 	}
963 
964 	ctx->pointer = p;
965 	ar_recycle_buffers(ctx, end_buffer_index);
966 
967 	return;
968 
969 error:
970 	ctx->pointer = NULL;
971 }
972 
973 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
974 			   unsigned int descriptors_offset, u32 regs)
975 {
976 	unsigned int i;
977 	dma_addr_t dma_addr;
978 	struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
979 	struct descriptor *d;
980 
981 	ctx->regs        = regs;
982 	ctx->ohci        = ohci;
983 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
984 
985 	for (i = 0; i < AR_BUFFERS; i++) {
986 		ctx->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32);
987 		if (!ctx->pages[i])
988 			goto out_of_memory;
989 		dma_addr = dma_map_page(ohci->card.device, ctx->pages[i],
990 					0, PAGE_SIZE, DMA_FROM_DEVICE);
991 		if (dma_mapping_error(ohci->card.device, dma_addr)) {
992 			__free_page(ctx->pages[i]);
993 			ctx->pages[i] = NULL;
994 			goto out_of_memory;
995 		}
996 		set_page_private(ctx->pages[i], dma_addr);
997 	}
998 
999 	for (i = 0; i < AR_BUFFERS; i++)
1000 		pages[i]              = ctx->pages[i];
1001 	for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
1002 		pages[AR_BUFFERS + i] = ctx->pages[i];
1003 	ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
1004 				 -1, PAGE_KERNEL);
1005 	if (!ctx->buffer)
1006 		goto out_of_memory;
1007 
1008 	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
1009 	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
1010 
1011 	for (i = 0; i < AR_BUFFERS; i++) {
1012 		d = &ctx->descriptors[i];
1013 		d->req_count      = cpu_to_le16(PAGE_SIZE);
1014 		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
1015 						DESCRIPTOR_STATUS |
1016 						DESCRIPTOR_BRANCH_ALWAYS);
1017 		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
1018 		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
1019 			ar_next_buffer_index(i) * sizeof(struct descriptor));
1020 	}
1021 
1022 	return 0;
1023 
1024 out_of_memory:
1025 	ar_context_release(ctx);
1026 
1027 	return -ENOMEM;
1028 }
1029 
1030 static void ar_context_run(struct ar_context *ctx)
1031 {
1032 	unsigned int i;
1033 
1034 	for (i = 0; i < AR_BUFFERS; i++)
1035 		ar_context_link_page(ctx, i);
1036 
1037 	ctx->pointer = ctx->buffer;
1038 
1039 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1040 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1041 }
1042 
1043 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1044 {
1045 	__le16 branch;
1046 
1047 	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1048 
1049 	/* figure out which descriptor the branch address goes in */
1050 	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1051 		return d;
1052 	else
1053 		return d + z - 1;
1054 }
1055 
1056 static void context_tasklet(unsigned long data)
1057 {
1058 	struct context *ctx = (struct context *) data;
1059 	struct descriptor *d, *last;
1060 	u32 address;
1061 	int z;
1062 	struct descriptor_buffer *desc;
1063 
1064 	desc = list_entry(ctx->buffer_list.next,
1065 			struct descriptor_buffer, list);
1066 	last = ctx->last;
1067 	while (last->branch_address != 0) {
1068 		struct descriptor_buffer *old_desc = desc;
1069 		address = le32_to_cpu(last->branch_address);
1070 		z = address & 0xf;
1071 		address &= ~0xf;
1072 		ctx->current_bus = address;
1073 
1074 		/* If the branch address points to a buffer outside of the
1075 		 * current buffer, advance to the next buffer. */
1076 		if (address < desc->buffer_bus ||
1077 				address >= desc->buffer_bus + desc->used)
1078 			desc = list_entry(desc->list.next,
1079 					struct descriptor_buffer, list);
1080 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1081 		last = find_branch_descriptor(d, z);
1082 
1083 		if (!ctx->callback(ctx, d, last))
1084 			break;
1085 
1086 		if (old_desc != desc) {
1087 			/* If we've advanced to the next buffer, move the
1088 			 * previous buffer to the free list. */
1089 			unsigned long flags;
1090 			old_desc->used = 0;
1091 			spin_lock_irqsave(&ctx->ohci->lock, flags);
1092 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1093 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1094 		}
1095 		ctx->last = last;
1096 	}
1097 }
1098 
1099 /*
1100  * Allocate a new buffer and add it to the list of free buffers for this
1101  * context.  Must be called with ohci->lock held.
1102  */
1103 static int context_add_buffer(struct context *ctx)
1104 {
1105 	struct descriptor_buffer *desc;
1106 	dma_addr_t uninitialized_var(bus_addr);
1107 	int offset;
1108 
1109 	/*
1110 	 * 16MB of descriptors should be far more than enough for any DMA
1111 	 * program.  This will catch run-away userspace or DoS attacks.
1112 	 */
1113 	if (ctx->total_allocation >= 16*1024*1024)
1114 		return -ENOMEM;
1115 
1116 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1117 			&bus_addr, GFP_ATOMIC);
1118 	if (!desc)
1119 		return -ENOMEM;
1120 
1121 	offset = (void *)&desc->buffer - (void *)desc;
1122 	desc->buffer_size = PAGE_SIZE - offset;
1123 	desc->buffer_bus = bus_addr + offset;
1124 	desc->used = 0;
1125 
1126 	list_add_tail(&desc->list, &ctx->buffer_list);
1127 	ctx->total_allocation += PAGE_SIZE;
1128 
1129 	return 0;
1130 }
1131 
1132 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1133 			u32 regs, descriptor_callback_t callback)
1134 {
1135 	ctx->ohci = ohci;
1136 	ctx->regs = regs;
1137 	ctx->total_allocation = 0;
1138 
1139 	INIT_LIST_HEAD(&ctx->buffer_list);
1140 	if (context_add_buffer(ctx) < 0)
1141 		return -ENOMEM;
1142 
1143 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1144 			struct descriptor_buffer, list);
1145 
1146 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1147 	ctx->callback = callback;
1148 
1149 	/*
1150 	 * We put a dummy descriptor in the buffer that has a NULL
1151 	 * branch address and looks like it's been sent.  That way we
1152 	 * have a descriptor to append DMA programs to.
1153 	 */
1154 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1155 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1156 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1157 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1158 	ctx->last = ctx->buffer_tail->buffer;
1159 	ctx->prev = ctx->buffer_tail->buffer;
1160 
1161 	return 0;
1162 }
1163 
1164 static void context_release(struct context *ctx)
1165 {
1166 	struct fw_card *card = &ctx->ohci->card;
1167 	struct descriptor_buffer *desc, *tmp;
1168 
1169 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1170 		dma_free_coherent(card->device, PAGE_SIZE, desc,
1171 			desc->buffer_bus -
1172 			((void *)&desc->buffer - (void *)desc));
1173 }
1174 
1175 /* Must be called with ohci->lock held */
1176 static struct descriptor *context_get_descriptors(struct context *ctx,
1177 						  int z, dma_addr_t *d_bus)
1178 {
1179 	struct descriptor *d = NULL;
1180 	struct descriptor_buffer *desc = ctx->buffer_tail;
1181 
1182 	if (z * sizeof(*d) > desc->buffer_size)
1183 		return NULL;
1184 
1185 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1186 		/* No room for the descriptor in this buffer, so advance to the
1187 		 * next one. */
1188 
1189 		if (desc->list.next == &ctx->buffer_list) {
1190 			/* If there is no free buffer next in the list,
1191 			 * allocate one. */
1192 			if (context_add_buffer(ctx) < 0)
1193 				return NULL;
1194 		}
1195 		desc = list_entry(desc->list.next,
1196 				struct descriptor_buffer, list);
1197 		ctx->buffer_tail = desc;
1198 	}
1199 
1200 	d = desc->buffer + desc->used / sizeof(*d);
1201 	memset(d, 0, z * sizeof(*d));
1202 	*d_bus = desc->buffer_bus + desc->used;
1203 
1204 	return d;
1205 }
1206 
1207 static void context_run(struct context *ctx, u32 extra)
1208 {
1209 	struct fw_ohci *ohci = ctx->ohci;
1210 
1211 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1212 		  le32_to_cpu(ctx->last->branch_address));
1213 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1214 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1215 	ctx->running = true;
1216 	flush_writes(ohci);
1217 }
1218 
1219 static void context_append(struct context *ctx,
1220 			   struct descriptor *d, int z, int extra)
1221 {
1222 	dma_addr_t d_bus;
1223 	struct descriptor_buffer *desc = ctx->buffer_tail;
1224 
1225 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1226 
1227 	desc->used += (z + extra) * sizeof(*d);
1228 
1229 	wmb(); /* finish init of new descriptors before branch_address update */
1230 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1231 	ctx->prev = find_branch_descriptor(d, z);
1232 }
1233 
1234 static void context_stop(struct context *ctx)
1235 {
1236 	struct fw_ohci *ohci = ctx->ohci;
1237 	u32 reg;
1238 	int i;
1239 
1240 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1241 	ctx->running = false;
1242 
1243 	for (i = 0; i < 1000; i++) {
1244 		reg = reg_read(ohci, CONTROL_SET(ctx->regs));
1245 		if ((reg & CONTEXT_ACTIVE) == 0)
1246 			return;
1247 
1248 		if (i)
1249 			udelay(10);
1250 	}
1251 	dev_err(ohci->card.device, "DMA context still active (0x%08x)\n", reg);
1252 }
1253 
1254 struct driver_data {
1255 	u8 inline_data[8];
1256 	struct fw_packet *packet;
1257 };
1258 
1259 /*
1260  * This function apppends a packet to the DMA queue for transmission.
1261  * Must always be called with the ochi->lock held to ensure proper
1262  * generation handling and locking around packet queue manipulation.
1263  */
1264 static int at_context_queue_packet(struct context *ctx,
1265 				   struct fw_packet *packet)
1266 {
1267 	struct fw_ohci *ohci = ctx->ohci;
1268 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1269 	struct driver_data *driver_data;
1270 	struct descriptor *d, *last;
1271 	__le32 *header;
1272 	int z, tcode;
1273 
1274 	d = context_get_descriptors(ctx, 4, &d_bus);
1275 	if (d == NULL) {
1276 		packet->ack = RCODE_SEND_ERROR;
1277 		return -1;
1278 	}
1279 
1280 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1281 	d[0].res_count = cpu_to_le16(packet->timestamp);
1282 
1283 	/*
1284 	 * The DMA format for asyncronous link packets is different
1285 	 * from the IEEE1394 layout, so shift the fields around
1286 	 * accordingly.
1287 	 */
1288 
1289 	tcode = (packet->header[0] >> 4) & 0x0f;
1290 	header = (__le32 *) &d[1];
1291 	switch (tcode) {
1292 	case TCODE_WRITE_QUADLET_REQUEST:
1293 	case TCODE_WRITE_BLOCK_REQUEST:
1294 	case TCODE_WRITE_RESPONSE:
1295 	case TCODE_READ_QUADLET_REQUEST:
1296 	case TCODE_READ_BLOCK_REQUEST:
1297 	case TCODE_READ_QUADLET_RESPONSE:
1298 	case TCODE_READ_BLOCK_RESPONSE:
1299 	case TCODE_LOCK_REQUEST:
1300 	case TCODE_LOCK_RESPONSE:
1301 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1302 					(packet->speed << 16));
1303 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1304 					(packet->header[0] & 0xffff0000));
1305 		header[2] = cpu_to_le32(packet->header[2]);
1306 
1307 		if (TCODE_IS_BLOCK_PACKET(tcode))
1308 			header[3] = cpu_to_le32(packet->header[3]);
1309 		else
1310 			header[3] = (__force __le32) packet->header[3];
1311 
1312 		d[0].req_count = cpu_to_le16(packet->header_length);
1313 		break;
1314 
1315 	case TCODE_LINK_INTERNAL:
1316 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1317 					(packet->speed << 16));
1318 		header[1] = cpu_to_le32(packet->header[1]);
1319 		header[2] = cpu_to_le32(packet->header[2]);
1320 		d[0].req_count = cpu_to_le16(12);
1321 
1322 		if (is_ping_packet(&packet->header[1]))
1323 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1324 		break;
1325 
1326 	case TCODE_STREAM_DATA:
1327 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1328 					(packet->speed << 16));
1329 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1330 		d[0].req_count = cpu_to_le16(8);
1331 		break;
1332 
1333 	default:
1334 		/* BUG(); */
1335 		packet->ack = RCODE_SEND_ERROR;
1336 		return -1;
1337 	}
1338 
1339 	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1340 	driver_data = (struct driver_data *) &d[3];
1341 	driver_data->packet = packet;
1342 	packet->driver_data = driver_data;
1343 
1344 	if (packet->payload_length > 0) {
1345 		if (packet->payload_length > sizeof(driver_data->inline_data)) {
1346 			payload_bus = dma_map_single(ohci->card.device,
1347 						     packet->payload,
1348 						     packet->payload_length,
1349 						     DMA_TO_DEVICE);
1350 			if (dma_mapping_error(ohci->card.device, payload_bus)) {
1351 				packet->ack = RCODE_SEND_ERROR;
1352 				return -1;
1353 			}
1354 			packet->payload_bus	= payload_bus;
1355 			packet->payload_mapped	= true;
1356 		} else {
1357 			memcpy(driver_data->inline_data, packet->payload,
1358 			       packet->payload_length);
1359 			payload_bus = d_bus + 3 * sizeof(*d);
1360 		}
1361 
1362 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1363 		d[2].data_address = cpu_to_le32(payload_bus);
1364 		last = &d[2];
1365 		z = 3;
1366 	} else {
1367 		last = &d[0];
1368 		z = 2;
1369 	}
1370 
1371 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1372 				     DESCRIPTOR_IRQ_ALWAYS |
1373 				     DESCRIPTOR_BRANCH_ALWAYS);
1374 
1375 	/* FIXME: Document how the locking works. */
1376 	if (ohci->generation != packet->generation) {
1377 		if (packet->payload_mapped)
1378 			dma_unmap_single(ohci->card.device, payload_bus,
1379 					 packet->payload_length, DMA_TO_DEVICE);
1380 		packet->ack = RCODE_GENERATION;
1381 		return -1;
1382 	}
1383 
1384 	context_append(ctx, d, z, 4 - z);
1385 
1386 	if (ctx->running)
1387 		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1388 	else
1389 		context_run(ctx, 0);
1390 
1391 	return 0;
1392 }
1393 
1394 static void at_context_flush(struct context *ctx)
1395 {
1396 	tasklet_disable(&ctx->tasklet);
1397 
1398 	ctx->flushing = true;
1399 	context_tasklet((unsigned long)ctx);
1400 	ctx->flushing = false;
1401 
1402 	tasklet_enable(&ctx->tasklet);
1403 }
1404 
1405 static int handle_at_packet(struct context *context,
1406 			    struct descriptor *d,
1407 			    struct descriptor *last)
1408 {
1409 	struct driver_data *driver_data;
1410 	struct fw_packet *packet;
1411 	struct fw_ohci *ohci = context->ohci;
1412 	int evt;
1413 
1414 	if (last->transfer_status == 0 && !context->flushing)
1415 		/* This descriptor isn't done yet, stop iteration. */
1416 		return 0;
1417 
1418 	driver_data = (struct driver_data *) &d[3];
1419 	packet = driver_data->packet;
1420 	if (packet == NULL)
1421 		/* This packet was cancelled, just continue. */
1422 		return 1;
1423 
1424 	if (packet->payload_mapped)
1425 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1426 				 packet->payload_length, DMA_TO_DEVICE);
1427 
1428 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1429 	packet->timestamp = le16_to_cpu(last->res_count);
1430 
1431 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);
1432 
1433 	switch (evt) {
1434 	case OHCI1394_evt_timeout:
1435 		/* Async response transmit timed out. */
1436 		packet->ack = RCODE_CANCELLED;
1437 		break;
1438 
1439 	case OHCI1394_evt_flushed:
1440 		/*
1441 		 * The packet was flushed should give same error as
1442 		 * when we try to use a stale generation count.
1443 		 */
1444 		packet->ack = RCODE_GENERATION;
1445 		break;
1446 
1447 	case OHCI1394_evt_missing_ack:
1448 		if (context->flushing)
1449 			packet->ack = RCODE_GENERATION;
1450 		else {
1451 			/*
1452 			 * Using a valid (current) generation count, but the
1453 			 * node is not on the bus or not sending acks.
1454 			 */
1455 			packet->ack = RCODE_NO_ACK;
1456 		}
1457 		break;
1458 
1459 	case ACK_COMPLETE + 0x10:
1460 	case ACK_PENDING + 0x10:
1461 	case ACK_BUSY_X + 0x10:
1462 	case ACK_BUSY_A + 0x10:
1463 	case ACK_BUSY_B + 0x10:
1464 	case ACK_DATA_ERROR + 0x10:
1465 	case ACK_TYPE_ERROR + 0x10:
1466 		packet->ack = evt - 0x10;
1467 		break;
1468 
1469 	case OHCI1394_evt_no_status:
1470 		if (context->flushing) {
1471 			packet->ack = RCODE_GENERATION;
1472 			break;
1473 		}
1474 		/* fall through */
1475 
1476 	default:
1477 		packet->ack = RCODE_SEND_ERROR;
1478 		break;
1479 	}
1480 
1481 	packet->callback(packet, &ohci->card, packet->ack);
1482 
1483 	return 1;
1484 }
1485 
1486 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1487 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1488 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1489 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1490 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1491 
1492 static void handle_local_rom(struct fw_ohci *ohci,
1493 			     struct fw_packet *packet, u32 csr)
1494 {
1495 	struct fw_packet response;
1496 	int tcode, length, i;
1497 
1498 	tcode = HEADER_GET_TCODE(packet->header[0]);
1499 	if (TCODE_IS_BLOCK_PACKET(tcode))
1500 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1501 	else
1502 		length = 4;
1503 
1504 	i = csr - CSR_CONFIG_ROM;
1505 	if (i + length > CONFIG_ROM_SIZE) {
1506 		fw_fill_response(&response, packet->header,
1507 				 RCODE_ADDRESS_ERROR, NULL, 0);
1508 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1509 		fw_fill_response(&response, packet->header,
1510 				 RCODE_TYPE_ERROR, NULL, 0);
1511 	} else {
1512 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1513 				 (void *) ohci->config_rom + i, length);
1514 	}
1515 
1516 	fw_core_handle_response(&ohci->card, &response);
1517 }
1518 
1519 static void handle_local_lock(struct fw_ohci *ohci,
1520 			      struct fw_packet *packet, u32 csr)
1521 {
1522 	struct fw_packet response;
1523 	int tcode, length, ext_tcode, sel, try;
1524 	__be32 *payload, lock_old;
1525 	u32 lock_arg, lock_data;
1526 
1527 	tcode = HEADER_GET_TCODE(packet->header[0]);
1528 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1529 	payload = packet->payload;
1530 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1531 
1532 	if (tcode == TCODE_LOCK_REQUEST &&
1533 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1534 		lock_arg = be32_to_cpu(payload[0]);
1535 		lock_data = be32_to_cpu(payload[1]);
1536 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1537 		lock_arg = 0;
1538 		lock_data = 0;
1539 	} else {
1540 		fw_fill_response(&response, packet->header,
1541 				 RCODE_TYPE_ERROR, NULL, 0);
1542 		goto out;
1543 	}
1544 
1545 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1546 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1547 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1548 	reg_write(ohci, OHCI1394_CSRControl, sel);
1549 
1550 	for (try = 0; try < 20; try++)
1551 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1552 			lock_old = cpu_to_be32(reg_read(ohci,
1553 							OHCI1394_CSRData));
1554 			fw_fill_response(&response, packet->header,
1555 					 RCODE_COMPLETE,
1556 					 &lock_old, sizeof(lock_old));
1557 			goto out;
1558 		}
1559 
1560 	dev_err(ohci->card.device, "swap not done (CSR lock timeout)\n");
1561 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1562 
1563  out:
1564 	fw_core_handle_response(&ohci->card, &response);
1565 }
1566 
1567 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1568 {
1569 	u64 offset, csr;
1570 
1571 	if (ctx == &ctx->ohci->at_request_ctx) {
1572 		packet->ack = ACK_PENDING;
1573 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1574 	}
1575 
1576 	offset =
1577 		((unsigned long long)
1578 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1579 		packet->header[2];
1580 	csr = offset - CSR_REGISTER_BASE;
1581 
1582 	/* Handle config rom reads. */
1583 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1584 		handle_local_rom(ctx->ohci, packet, csr);
1585 	else switch (csr) {
1586 	case CSR_BUS_MANAGER_ID:
1587 	case CSR_BANDWIDTH_AVAILABLE:
1588 	case CSR_CHANNELS_AVAILABLE_HI:
1589 	case CSR_CHANNELS_AVAILABLE_LO:
1590 		handle_local_lock(ctx->ohci, packet, csr);
1591 		break;
1592 	default:
1593 		if (ctx == &ctx->ohci->at_request_ctx)
1594 			fw_core_handle_request(&ctx->ohci->card, packet);
1595 		else
1596 			fw_core_handle_response(&ctx->ohci->card, packet);
1597 		break;
1598 	}
1599 
1600 	if (ctx == &ctx->ohci->at_response_ctx) {
1601 		packet->ack = ACK_COMPLETE;
1602 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1603 	}
1604 }
1605 
1606 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1607 {
1608 	unsigned long flags;
1609 	int ret;
1610 
1611 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1612 
1613 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1614 	    ctx->ohci->generation == packet->generation) {
1615 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1616 		handle_local_request(ctx, packet);
1617 		return;
1618 	}
1619 
1620 	ret = at_context_queue_packet(ctx, packet);
1621 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1622 
1623 	if (ret < 0)
1624 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1625 
1626 }
1627 
1628 static void detect_dead_context(struct fw_ohci *ohci,
1629 				const char *name, unsigned int regs)
1630 {
1631 	u32 ctl;
1632 
1633 	ctl = reg_read(ohci, CONTROL_SET(regs));
1634 	if (ctl & CONTEXT_DEAD)
1635 		dev_err(ohci->card.device,
1636 			"DMA context %s has stopped, error code: %s\n",
1637 			name, evts[ctl & 0x1f]);
1638 }
1639 
1640 static void handle_dead_contexts(struct fw_ohci *ohci)
1641 {
1642 	unsigned int i;
1643 	char name[8];
1644 
1645 	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1646 	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1647 	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1648 	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1649 	for (i = 0; i < 32; ++i) {
1650 		if (!(ohci->it_context_support & (1 << i)))
1651 			continue;
1652 		sprintf(name, "IT%u", i);
1653 		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1654 	}
1655 	for (i = 0; i < 32; ++i) {
1656 		if (!(ohci->ir_context_support & (1 << i)))
1657 			continue;
1658 		sprintf(name, "IR%u", i);
1659 		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1660 	}
1661 	/* TODO: maybe try to flush and restart the dead contexts */
1662 }
1663 
1664 static u32 cycle_timer_ticks(u32 cycle_timer)
1665 {
1666 	u32 ticks;
1667 
1668 	ticks = cycle_timer & 0xfff;
1669 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1670 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1671 
1672 	return ticks;
1673 }
1674 
1675 /*
1676  * Some controllers exhibit one or more of the following bugs when updating the
1677  * iso cycle timer register:
1678  *  - When the lowest six bits are wrapping around to zero, a read that happens
1679  *    at the same time will return garbage in the lowest ten bits.
1680  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1681  *    not incremented for about 60 ns.
1682  *  - Occasionally, the entire register reads zero.
1683  *
1684  * To catch these, we read the register three times and ensure that the
1685  * difference between each two consecutive reads is approximately the same, i.e.
1686  * less than twice the other.  Furthermore, any negative difference indicates an
1687  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1688  * execute, so we have enough precision to compute the ratio of the differences.)
1689  */
1690 static u32 get_cycle_time(struct fw_ohci *ohci)
1691 {
1692 	u32 c0, c1, c2;
1693 	u32 t0, t1, t2;
1694 	s32 diff01, diff12;
1695 	int i;
1696 
1697 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1698 
1699 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1700 		i = 0;
1701 		c1 = c2;
1702 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1703 		do {
1704 			c0 = c1;
1705 			c1 = c2;
1706 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1707 			t0 = cycle_timer_ticks(c0);
1708 			t1 = cycle_timer_ticks(c1);
1709 			t2 = cycle_timer_ticks(c2);
1710 			diff01 = t1 - t0;
1711 			diff12 = t2 - t1;
1712 		} while ((diff01 <= 0 || diff12 <= 0 ||
1713 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1714 			 && i++ < 20);
1715 	}
1716 
1717 	return c2;
1718 }
1719 
1720 /*
1721  * This function has to be called at least every 64 seconds.  The bus_time
1722  * field stores not only the upper 25 bits of the BUS_TIME register but also
1723  * the most significant bit of the cycle timer in bit 6 so that we can detect
1724  * changes in this bit.
1725  */
1726 static u32 update_bus_time(struct fw_ohci *ohci)
1727 {
1728 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1729 
1730 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1731 		ohci->bus_time += 0x40;
1732 
1733 	return ohci->bus_time | cycle_time_seconds;
1734 }
1735 
1736 static int get_status_for_port(struct fw_ohci *ohci, int port_index)
1737 {
1738 	int reg;
1739 
1740 	mutex_lock(&ohci->phy_reg_mutex);
1741 	reg = write_phy_reg(ohci, 7, port_index);
1742 	if (reg >= 0)
1743 		reg = read_phy_reg(ohci, 8);
1744 	mutex_unlock(&ohci->phy_reg_mutex);
1745 	if (reg < 0)
1746 		return reg;
1747 
1748 	switch (reg & 0x0f) {
1749 	case 0x06:
1750 		return 2;	/* is child node (connected to parent node) */
1751 	case 0x0e:
1752 		return 3;	/* is parent node (connected to child node) */
1753 	}
1754 	return 1;		/* not connected */
1755 }
1756 
1757 static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
1758 	int self_id_count)
1759 {
1760 	int i;
1761 	u32 entry;
1762 
1763 	for (i = 0; i < self_id_count; i++) {
1764 		entry = ohci->self_id_buffer[i];
1765 		if ((self_id & 0xff000000) == (entry & 0xff000000))
1766 			return -1;
1767 		if ((self_id & 0xff000000) < (entry & 0xff000000))
1768 			return i;
1769 	}
1770 	return i;
1771 }
1772 
1773 /*
1774  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1775  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1776  * Construct the selfID from phy register contents.
1777  * FIXME:  How to determine the selfID.i flag?
1778  */
1779 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
1780 {
1781 	int reg, i, pos, status;
1782 	/* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
1783 	u32 self_id = 0x8040c800;
1784 
1785 	reg = reg_read(ohci, OHCI1394_NodeID);
1786 	if (!(reg & OHCI1394_NodeID_idValid)) {
1787 		dev_notice(ohci->card.device,
1788 			   "node ID not valid, new bus reset in progress\n");
1789 		return -EBUSY;
1790 	}
1791 	self_id |= ((reg & 0x3f) << 24); /* phy ID */
1792 
1793 	reg = ohci_read_phy_reg(&ohci->card, 4);
1794 	if (reg < 0)
1795 		return reg;
1796 	self_id |= ((reg & 0x07) << 8); /* power class */
1797 
1798 	reg = ohci_read_phy_reg(&ohci->card, 1);
1799 	if (reg < 0)
1800 		return reg;
1801 	self_id |= ((reg & 0x3f) << 16); /* gap count */
1802 
1803 	for (i = 0; i < 3; i++) {
1804 		status = get_status_for_port(ohci, i);
1805 		if (status < 0)
1806 			return status;
1807 		self_id |= ((status & 0x3) << (6 - (i * 2)));
1808 	}
1809 
1810 	pos = get_self_id_pos(ohci, self_id, self_id_count);
1811 	if (pos >= 0) {
1812 		memmove(&(ohci->self_id_buffer[pos+1]),
1813 			&(ohci->self_id_buffer[pos]),
1814 			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
1815 		ohci->self_id_buffer[pos] = self_id;
1816 		self_id_count++;
1817 	}
1818 	return self_id_count;
1819 }
1820 
1821 static void bus_reset_work(struct work_struct *work)
1822 {
1823 	struct fw_ohci *ohci =
1824 		container_of(work, struct fw_ohci, bus_reset_work);
1825 	int self_id_count, i, j, reg;
1826 	int generation, new_generation;
1827 	unsigned long flags;
1828 	void *free_rom = NULL;
1829 	dma_addr_t free_rom_bus = 0;
1830 	bool is_new_root;
1831 
1832 	reg = reg_read(ohci, OHCI1394_NodeID);
1833 	if (!(reg & OHCI1394_NodeID_idValid)) {
1834 		dev_notice(ohci->card.device,
1835 			   "node ID not valid, new bus reset in progress\n");
1836 		return;
1837 	}
1838 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1839 		dev_notice(ohci->card.device, "malconfigured bus\n");
1840 		return;
1841 	}
1842 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1843 			       OHCI1394_NodeID_nodeNumber);
1844 
1845 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1846 	if (!(ohci->is_root && is_new_root))
1847 		reg_write(ohci, OHCI1394_LinkControlSet,
1848 			  OHCI1394_LinkControl_cycleMaster);
1849 	ohci->is_root = is_new_root;
1850 
1851 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1852 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1853 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1854 		return;
1855 	}
1856 	/*
1857 	 * The count in the SelfIDCount register is the number of
1858 	 * bytes in the self ID receive buffer.  Since we also receive
1859 	 * the inverted quadlets and a header quadlet, we shift one
1860 	 * bit extra to get the actual number of self IDs.
1861 	 */
1862 	self_id_count = (reg >> 3) & 0xff;
1863 
1864 	if (self_id_count > 252) {
1865 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1866 		return;
1867 	}
1868 
1869 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1870 	rmb();
1871 
1872 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1873 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1874 			/*
1875 			 * If the invalid data looks like a cycle start packet,
1876 			 * it's likely to be the result of the cycle master
1877 			 * having a wrong gap count.  In this case, the self IDs
1878 			 * so far are valid and should be processed so that the
1879 			 * bus manager can then correct the gap count.
1880 			 */
1881 			if (cond_le32_to_cpu(ohci->self_id_cpu[i])
1882 							== 0xffff008f) {
1883 				dev_notice(ohci->card.device,
1884 					   "ignoring spurious self IDs\n");
1885 				self_id_count = j;
1886 				break;
1887 			} else {
1888 				dev_notice(ohci->card.device,
1889 					   "inconsistent self IDs\n");
1890 				return;
1891 			}
1892 		}
1893 		ohci->self_id_buffer[j] =
1894 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1895 	}
1896 
1897 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
1898 		self_id_count = find_and_insert_self_id(ohci, self_id_count);
1899 		if (self_id_count < 0) {
1900 			dev_notice(ohci->card.device,
1901 				   "could not construct local self ID\n");
1902 			return;
1903 		}
1904 	}
1905 
1906 	if (self_id_count == 0) {
1907 		dev_notice(ohci->card.device, "inconsistent self IDs\n");
1908 		return;
1909 	}
1910 	rmb();
1911 
1912 	/*
1913 	 * Check the consistency of the self IDs we just read.  The
1914 	 * problem we face is that a new bus reset can start while we
1915 	 * read out the self IDs from the DMA buffer. If this happens,
1916 	 * the DMA buffer will be overwritten with new self IDs and we
1917 	 * will read out inconsistent data.  The OHCI specification
1918 	 * (section 11.2) recommends a technique similar to
1919 	 * linux/seqlock.h, where we remember the generation of the
1920 	 * self IDs in the buffer before reading them out and compare
1921 	 * it to the current generation after reading them out.  If
1922 	 * the two generations match we know we have a consistent set
1923 	 * of self IDs.
1924 	 */
1925 
1926 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1927 	if (new_generation != generation) {
1928 		dev_notice(ohci->card.device,
1929 			   "new bus reset, discarding self ids\n");
1930 		return;
1931 	}
1932 
1933 	/* FIXME: Document how the locking works. */
1934 	spin_lock_irqsave(&ohci->lock, flags);
1935 
1936 	ohci->generation = -1; /* prevent AT packet queueing */
1937 	context_stop(&ohci->at_request_ctx);
1938 	context_stop(&ohci->at_response_ctx);
1939 
1940 	spin_unlock_irqrestore(&ohci->lock, flags);
1941 
1942 	/*
1943 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
1944 	 * packets in the AT queues and software needs to drain them.
1945 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
1946 	 */
1947 	at_context_flush(&ohci->at_request_ctx);
1948 	at_context_flush(&ohci->at_response_ctx);
1949 
1950 	spin_lock_irqsave(&ohci->lock, flags);
1951 
1952 	ohci->generation = generation;
1953 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1954 
1955 	if (ohci->quirks & QUIRK_RESET_PACKET)
1956 		ohci->request_generation = generation;
1957 
1958 	/*
1959 	 * This next bit is unrelated to the AT context stuff but we
1960 	 * have to do it under the spinlock also.  If a new config rom
1961 	 * was set up before this reset, the old one is now no longer
1962 	 * in use and we can free it. Update the config rom pointers
1963 	 * to point to the current config rom and clear the
1964 	 * next_config_rom pointer so a new update can take place.
1965 	 */
1966 
1967 	if (ohci->next_config_rom != NULL) {
1968 		if (ohci->next_config_rom != ohci->config_rom) {
1969 			free_rom      = ohci->config_rom;
1970 			free_rom_bus  = ohci->config_rom_bus;
1971 		}
1972 		ohci->config_rom      = ohci->next_config_rom;
1973 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1974 		ohci->next_config_rom = NULL;
1975 
1976 		/*
1977 		 * Restore config_rom image and manually update
1978 		 * config_rom registers.  Writing the header quadlet
1979 		 * will indicate that the config rom is ready, so we
1980 		 * do that last.
1981 		 */
1982 		reg_write(ohci, OHCI1394_BusOptions,
1983 			  be32_to_cpu(ohci->config_rom[2]));
1984 		ohci->config_rom[0] = ohci->next_header;
1985 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1986 			  be32_to_cpu(ohci->next_header));
1987 	}
1988 
1989 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1990 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1991 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1992 #endif
1993 
1994 	spin_unlock_irqrestore(&ohci->lock, flags);
1995 
1996 	if (free_rom)
1997 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1998 				  free_rom, free_rom_bus);
1999 
2000 	log_selfids(ohci, generation, self_id_count);
2001 
2002 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2003 				 self_id_count, ohci->self_id_buffer,
2004 				 ohci->csr_state_setclear_abdicate);
2005 	ohci->csr_state_setclear_abdicate = false;
2006 }
2007 
2008 static irqreturn_t irq_handler(int irq, void *data)
2009 {
2010 	struct fw_ohci *ohci = data;
2011 	u32 event, iso_event;
2012 	int i;
2013 
2014 	event = reg_read(ohci, OHCI1394_IntEventClear);
2015 
2016 	if (!event || !~event)
2017 		return IRQ_NONE;
2018 
2019 	/*
2020 	 * busReset and postedWriteErr must not be cleared yet
2021 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2022 	 */
2023 	reg_write(ohci, OHCI1394_IntEventClear,
2024 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2025 	log_irqs(ohci, event);
2026 
2027 	if (event & OHCI1394_selfIDComplete)
2028 		queue_work(fw_workqueue, &ohci->bus_reset_work);
2029 
2030 	if (event & OHCI1394_RQPkt)
2031 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2032 
2033 	if (event & OHCI1394_RSPkt)
2034 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2035 
2036 	if (event & OHCI1394_reqTxComplete)
2037 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
2038 
2039 	if (event & OHCI1394_respTxComplete)
2040 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
2041 
2042 	if (event & OHCI1394_isochRx) {
2043 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2044 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2045 
2046 		while (iso_event) {
2047 			i = ffs(iso_event) - 1;
2048 			tasklet_schedule(
2049 				&ohci->ir_context_list[i].context.tasklet);
2050 			iso_event &= ~(1 << i);
2051 		}
2052 	}
2053 
2054 	if (event & OHCI1394_isochTx) {
2055 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2056 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2057 
2058 		while (iso_event) {
2059 			i = ffs(iso_event) - 1;
2060 			tasklet_schedule(
2061 				&ohci->it_context_list[i].context.tasklet);
2062 			iso_event &= ~(1 << i);
2063 		}
2064 	}
2065 
2066 	if (unlikely(event & OHCI1394_regAccessFail))
2067 		dev_err(ohci->card.device, "register access failure\n");
2068 
2069 	if (unlikely(event & OHCI1394_postedWriteErr)) {
2070 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2071 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2072 		reg_write(ohci, OHCI1394_IntEventClear,
2073 			  OHCI1394_postedWriteErr);
2074 		if (printk_ratelimit())
2075 			dev_err(ohci->card.device, "PCI posted write error\n");
2076 	}
2077 
2078 	if (unlikely(event & OHCI1394_cycleTooLong)) {
2079 		if (printk_ratelimit())
2080 			dev_notice(ohci->card.device,
2081 				   "isochronous cycle too long\n");
2082 		reg_write(ohci, OHCI1394_LinkControlSet,
2083 			  OHCI1394_LinkControl_cycleMaster);
2084 	}
2085 
2086 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
2087 		/*
2088 		 * We need to clear this event bit in order to make
2089 		 * cycleMatch isochronous I/O work.  In theory we should
2090 		 * stop active cycleMatch iso contexts now and restart
2091 		 * them at least two cycles later.  (FIXME?)
2092 		 */
2093 		if (printk_ratelimit())
2094 			dev_notice(ohci->card.device,
2095 				   "isochronous cycle inconsistent\n");
2096 	}
2097 
2098 	if (unlikely(event & OHCI1394_unrecoverableError))
2099 		handle_dead_contexts(ohci);
2100 
2101 	if (event & OHCI1394_cycle64Seconds) {
2102 		spin_lock(&ohci->lock);
2103 		update_bus_time(ohci);
2104 		spin_unlock(&ohci->lock);
2105 	} else
2106 		flush_writes(ohci);
2107 
2108 	return IRQ_HANDLED;
2109 }
2110 
2111 static int software_reset(struct fw_ohci *ohci)
2112 {
2113 	u32 val;
2114 	int i;
2115 
2116 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2117 	for (i = 0; i < 500; i++) {
2118 		val = reg_read(ohci, OHCI1394_HCControlSet);
2119 		if (!~val)
2120 			return -ENODEV; /* Card was ejected. */
2121 
2122 		if (!(val & OHCI1394_HCControl_softReset))
2123 			return 0;
2124 
2125 		msleep(1);
2126 	}
2127 
2128 	return -EBUSY;
2129 }
2130 
2131 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2132 {
2133 	size_t size = length * 4;
2134 
2135 	memcpy(dest, src, size);
2136 	if (size < CONFIG_ROM_SIZE)
2137 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2138 }
2139 
2140 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2141 {
2142 	bool enable_1394a;
2143 	int ret, clear, set, offset;
2144 
2145 	/* Check if the driver should configure link and PHY. */
2146 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2147 	      OHCI1394_HCControl_programPhyEnable))
2148 		return 0;
2149 
2150 	/* Paranoia: check whether the PHY supports 1394a, too. */
2151 	enable_1394a = false;
2152 	ret = read_phy_reg(ohci, 2);
2153 	if (ret < 0)
2154 		return ret;
2155 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2156 		ret = read_paged_phy_reg(ohci, 1, 8);
2157 		if (ret < 0)
2158 			return ret;
2159 		if (ret >= 1)
2160 			enable_1394a = true;
2161 	}
2162 
2163 	if (ohci->quirks & QUIRK_NO_1394A)
2164 		enable_1394a = false;
2165 
2166 	/* Configure PHY and link consistently. */
2167 	if (enable_1394a) {
2168 		clear = 0;
2169 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2170 	} else {
2171 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2172 		set = 0;
2173 	}
2174 	ret = update_phy_reg(ohci, 5, clear, set);
2175 	if (ret < 0)
2176 		return ret;
2177 
2178 	if (enable_1394a)
2179 		offset = OHCI1394_HCControlSet;
2180 	else
2181 		offset = OHCI1394_HCControlClear;
2182 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2183 
2184 	/* Clean up: configuration has been taken care of. */
2185 	reg_write(ohci, OHCI1394_HCControlClear,
2186 		  OHCI1394_HCControl_programPhyEnable);
2187 
2188 	return 0;
2189 }
2190 
2191 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2192 {
2193 	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2194 	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2195 	int reg, i;
2196 
2197 	reg = read_phy_reg(ohci, 2);
2198 	if (reg < 0)
2199 		return reg;
2200 	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2201 		return 0;
2202 
2203 	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2204 		reg = read_paged_phy_reg(ohci, 1, i + 10);
2205 		if (reg < 0)
2206 			return reg;
2207 		if (reg != id[i])
2208 			return 0;
2209 	}
2210 	return 1;
2211 }
2212 
2213 static int ohci_enable(struct fw_card *card,
2214 		       const __be32 *config_rom, size_t length)
2215 {
2216 	struct fw_ohci *ohci = fw_ohci(card);
2217 	struct pci_dev *dev = to_pci_dev(card->device);
2218 	u32 lps, seconds, version, irqs;
2219 	int i, ret;
2220 
2221 	if (software_reset(ohci)) {
2222 		dev_err(card->device, "failed to reset ohci card\n");
2223 		return -EBUSY;
2224 	}
2225 
2226 	/*
2227 	 * Now enable LPS, which we need in order to start accessing
2228 	 * most of the registers.  In fact, on some cards (ALI M5251),
2229 	 * accessing registers in the SClk domain without LPS enabled
2230 	 * will lock up the machine.  Wait 50msec to make sure we have
2231 	 * full link enabled.  However, with some cards (well, at least
2232 	 * a JMicron PCIe card), we have to try again sometimes.
2233 	 */
2234 	reg_write(ohci, OHCI1394_HCControlSet,
2235 		  OHCI1394_HCControl_LPS |
2236 		  OHCI1394_HCControl_postedWriteEnable);
2237 	flush_writes(ohci);
2238 
2239 	for (lps = 0, i = 0; !lps && i < 3; i++) {
2240 		msleep(50);
2241 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2242 		      OHCI1394_HCControl_LPS;
2243 	}
2244 
2245 	if (!lps) {
2246 		dev_err(card->device, "failed to set Link Power Status\n");
2247 		return -EIO;
2248 	}
2249 
2250 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2251 		ret = probe_tsb41ba3d(ohci);
2252 		if (ret < 0)
2253 			return ret;
2254 		if (ret)
2255 			dev_notice(card->device, "local TSB41BA3D phy\n");
2256 		else
2257 			ohci->quirks &= ~QUIRK_TI_SLLZ059;
2258 	}
2259 
2260 	reg_write(ohci, OHCI1394_HCControlClear,
2261 		  OHCI1394_HCControl_noByteSwapData);
2262 
2263 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2264 	reg_write(ohci, OHCI1394_LinkControlSet,
2265 		  OHCI1394_LinkControl_cycleTimerEnable |
2266 		  OHCI1394_LinkControl_cycleMaster);
2267 
2268 	reg_write(ohci, OHCI1394_ATRetries,
2269 		  OHCI1394_MAX_AT_REQ_RETRIES |
2270 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2271 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2272 		  (200 << 16));
2273 
2274 	seconds = lower_32_bits(get_seconds());
2275 	reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
2276 	ohci->bus_time = seconds & ~0x3f;
2277 
2278 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2279 	if (version >= OHCI_VERSION_1_1) {
2280 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2281 			  0xfffffffe);
2282 		card->broadcast_channel_auto_allocated = true;
2283 	}
2284 
2285 	/* Get implemented bits of the priority arbitration request counter. */
2286 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2287 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2288 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2289 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2290 
2291 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
2292 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2293 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2294 
2295 	ret = configure_1394a_enhancements(ohci);
2296 	if (ret < 0)
2297 		return ret;
2298 
2299 	/* Activate link_on bit and contender bit in our self ID packets.*/
2300 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2301 	if (ret < 0)
2302 		return ret;
2303 
2304 	/*
2305 	 * When the link is not yet enabled, the atomic config rom
2306 	 * update mechanism described below in ohci_set_config_rom()
2307 	 * is not active.  We have to update ConfigRomHeader and
2308 	 * BusOptions manually, and the write to ConfigROMmap takes
2309 	 * effect immediately.  We tie this to the enabling of the
2310 	 * link, so we have a valid config rom before enabling - the
2311 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2312 	 * values before enabling.
2313 	 *
2314 	 * However, when the ConfigROMmap is written, some controllers
2315 	 * always read back quadlets 0 and 2 from the config rom to
2316 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2317 	 * They shouldn't do that in this initial case where the link
2318 	 * isn't enabled.  This means we have to use the same
2319 	 * workaround here, setting the bus header to 0 and then write
2320 	 * the right values in the bus reset tasklet.
2321 	 */
2322 
2323 	if (config_rom) {
2324 		ohci->next_config_rom =
2325 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2326 					   &ohci->next_config_rom_bus,
2327 					   GFP_KERNEL);
2328 		if (ohci->next_config_rom == NULL)
2329 			return -ENOMEM;
2330 
2331 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2332 	} else {
2333 		/*
2334 		 * In the suspend case, config_rom is NULL, which
2335 		 * means that we just reuse the old config rom.
2336 		 */
2337 		ohci->next_config_rom = ohci->config_rom;
2338 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2339 	}
2340 
2341 	ohci->next_header = ohci->next_config_rom[0];
2342 	ohci->next_config_rom[0] = 0;
2343 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2344 	reg_write(ohci, OHCI1394_BusOptions,
2345 		  be32_to_cpu(ohci->next_config_rom[2]));
2346 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2347 
2348 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2349 
2350 	if (!(ohci->quirks & QUIRK_NO_MSI))
2351 		pci_enable_msi(dev);
2352 	if (request_irq(dev->irq, irq_handler,
2353 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
2354 			ohci_driver_name, ohci)) {
2355 		dev_err(card->device, "failed to allocate interrupt %d\n",
2356 			dev->irq);
2357 		pci_disable_msi(dev);
2358 
2359 		if (config_rom) {
2360 			dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2361 					  ohci->next_config_rom,
2362 					  ohci->next_config_rom_bus);
2363 			ohci->next_config_rom = NULL;
2364 		}
2365 		return -EIO;
2366 	}
2367 
2368 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2369 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2370 		OHCI1394_isochTx | OHCI1394_isochRx |
2371 		OHCI1394_postedWriteErr |
2372 		OHCI1394_selfIDComplete |
2373 		OHCI1394_regAccessFail |
2374 		OHCI1394_cycle64Seconds |
2375 		OHCI1394_cycleInconsistent |
2376 		OHCI1394_unrecoverableError |
2377 		OHCI1394_cycleTooLong |
2378 		OHCI1394_masterIntEnable;
2379 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2380 		irqs |= OHCI1394_busReset;
2381 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2382 
2383 	reg_write(ohci, OHCI1394_HCControlSet,
2384 		  OHCI1394_HCControl_linkEnable |
2385 		  OHCI1394_HCControl_BIBimageValid);
2386 
2387 	reg_write(ohci, OHCI1394_LinkControlSet,
2388 		  OHCI1394_LinkControl_rcvSelfID |
2389 		  OHCI1394_LinkControl_rcvPhyPkt);
2390 
2391 	ar_context_run(&ohci->ar_request_ctx);
2392 	ar_context_run(&ohci->ar_response_ctx);
2393 
2394 	flush_writes(ohci);
2395 
2396 	/* We are ready to go, reset bus to finish initialization. */
2397 	fw_schedule_bus_reset(&ohci->card, false, true);
2398 
2399 	return 0;
2400 }
2401 
2402 static int ohci_set_config_rom(struct fw_card *card,
2403 			       const __be32 *config_rom, size_t length)
2404 {
2405 	struct fw_ohci *ohci;
2406 	unsigned long flags;
2407 	__be32 *next_config_rom;
2408 	dma_addr_t uninitialized_var(next_config_rom_bus);
2409 
2410 	ohci = fw_ohci(card);
2411 
2412 	/*
2413 	 * When the OHCI controller is enabled, the config rom update
2414 	 * mechanism is a bit tricky, but easy enough to use.  See
2415 	 * section 5.5.6 in the OHCI specification.
2416 	 *
2417 	 * The OHCI controller caches the new config rom address in a
2418 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2419 	 * for the changes to take place.  When the bus reset is
2420 	 * detected, the controller loads the new values for the
2421 	 * ConfigRomHeader and BusOptions registers from the specified
2422 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2423 	 * shadow register. All automatically and atomically.
2424 	 *
2425 	 * Now, there's a twist to this story.  The automatic load of
2426 	 * ConfigRomHeader and BusOptions doesn't honor the
2427 	 * noByteSwapData bit, so with a be32 config rom, the
2428 	 * controller will load be32 values in to these registers
2429 	 * during the atomic update, even on litte endian
2430 	 * architectures.  The workaround we use is to put a 0 in the
2431 	 * header quadlet; 0 is endian agnostic and means that the
2432 	 * config rom isn't ready yet.  In the bus reset tasklet we
2433 	 * then set up the real values for the two registers.
2434 	 *
2435 	 * We use ohci->lock to avoid racing with the code that sets
2436 	 * ohci->next_config_rom to NULL (see bus_reset_work).
2437 	 */
2438 
2439 	next_config_rom =
2440 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2441 				   &next_config_rom_bus, GFP_KERNEL);
2442 	if (next_config_rom == NULL)
2443 		return -ENOMEM;
2444 
2445 	spin_lock_irqsave(&ohci->lock, flags);
2446 
2447 	/*
2448 	 * If there is not an already pending config_rom update,
2449 	 * push our new allocation into the ohci->next_config_rom
2450 	 * and then mark the local variable as null so that we
2451 	 * won't deallocate the new buffer.
2452 	 *
2453 	 * OTOH, if there is a pending config_rom update, just
2454 	 * use that buffer with the new config_rom data, and
2455 	 * let this routine free the unused DMA allocation.
2456 	 */
2457 
2458 	if (ohci->next_config_rom == NULL) {
2459 		ohci->next_config_rom = next_config_rom;
2460 		ohci->next_config_rom_bus = next_config_rom_bus;
2461 		next_config_rom = NULL;
2462 	}
2463 
2464 	copy_config_rom(ohci->next_config_rom, config_rom, length);
2465 
2466 	ohci->next_header = config_rom[0];
2467 	ohci->next_config_rom[0] = 0;
2468 
2469 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2470 
2471 	spin_unlock_irqrestore(&ohci->lock, flags);
2472 
2473 	/* If we didn't use the DMA allocation, delete it. */
2474 	if (next_config_rom != NULL)
2475 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2476 				  next_config_rom, next_config_rom_bus);
2477 
2478 	/*
2479 	 * Now initiate a bus reset to have the changes take
2480 	 * effect. We clean up the old config rom memory and DMA
2481 	 * mappings in the bus reset tasklet, since the OHCI
2482 	 * controller could need to access it before the bus reset
2483 	 * takes effect.
2484 	 */
2485 
2486 	fw_schedule_bus_reset(&ohci->card, true, true);
2487 
2488 	return 0;
2489 }
2490 
2491 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2492 {
2493 	struct fw_ohci *ohci = fw_ohci(card);
2494 
2495 	at_context_transmit(&ohci->at_request_ctx, packet);
2496 }
2497 
2498 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2499 {
2500 	struct fw_ohci *ohci = fw_ohci(card);
2501 
2502 	at_context_transmit(&ohci->at_response_ctx, packet);
2503 }
2504 
2505 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2506 {
2507 	struct fw_ohci *ohci = fw_ohci(card);
2508 	struct context *ctx = &ohci->at_request_ctx;
2509 	struct driver_data *driver_data = packet->driver_data;
2510 	int ret = -ENOENT;
2511 
2512 	tasklet_disable(&ctx->tasklet);
2513 
2514 	if (packet->ack != 0)
2515 		goto out;
2516 
2517 	if (packet->payload_mapped)
2518 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2519 				 packet->payload_length, DMA_TO_DEVICE);
2520 
2521 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2522 	driver_data->packet = NULL;
2523 	packet->ack = RCODE_CANCELLED;
2524 	packet->callback(packet, &ohci->card, packet->ack);
2525 	ret = 0;
2526  out:
2527 	tasklet_enable(&ctx->tasklet);
2528 
2529 	return ret;
2530 }
2531 
2532 static int ohci_enable_phys_dma(struct fw_card *card,
2533 				int node_id, int generation)
2534 {
2535 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2536 	return 0;
2537 #else
2538 	struct fw_ohci *ohci = fw_ohci(card);
2539 	unsigned long flags;
2540 	int n, ret = 0;
2541 
2542 	/*
2543 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2544 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2545 	 */
2546 
2547 	spin_lock_irqsave(&ohci->lock, flags);
2548 
2549 	if (ohci->generation != generation) {
2550 		ret = -ESTALE;
2551 		goto out;
2552 	}
2553 
2554 	/*
2555 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2556 	 * enabled for _all_ nodes on remote buses.
2557 	 */
2558 
2559 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2560 	if (n < 32)
2561 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2562 	else
2563 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2564 
2565 	flush_writes(ohci);
2566  out:
2567 	spin_unlock_irqrestore(&ohci->lock, flags);
2568 
2569 	return ret;
2570 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2571 }
2572 
2573 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2574 {
2575 	struct fw_ohci *ohci = fw_ohci(card);
2576 	unsigned long flags;
2577 	u32 value;
2578 
2579 	switch (csr_offset) {
2580 	case CSR_STATE_CLEAR:
2581 	case CSR_STATE_SET:
2582 		if (ohci->is_root &&
2583 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2584 		     OHCI1394_LinkControl_cycleMaster))
2585 			value = CSR_STATE_BIT_CMSTR;
2586 		else
2587 			value = 0;
2588 		if (ohci->csr_state_setclear_abdicate)
2589 			value |= CSR_STATE_BIT_ABDICATE;
2590 
2591 		return value;
2592 
2593 	case CSR_NODE_IDS:
2594 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2595 
2596 	case CSR_CYCLE_TIME:
2597 		return get_cycle_time(ohci);
2598 
2599 	case CSR_BUS_TIME:
2600 		/*
2601 		 * We might be called just after the cycle timer has wrapped
2602 		 * around but just before the cycle64Seconds handler, so we
2603 		 * better check here, too, if the bus time needs to be updated.
2604 		 */
2605 		spin_lock_irqsave(&ohci->lock, flags);
2606 		value = update_bus_time(ohci);
2607 		spin_unlock_irqrestore(&ohci->lock, flags);
2608 		return value;
2609 
2610 	case CSR_BUSY_TIMEOUT:
2611 		value = reg_read(ohci, OHCI1394_ATRetries);
2612 		return (value >> 4) & 0x0ffff00f;
2613 
2614 	case CSR_PRIORITY_BUDGET:
2615 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2616 			(ohci->pri_req_max << 8);
2617 
2618 	default:
2619 		WARN_ON(1);
2620 		return 0;
2621 	}
2622 }
2623 
2624 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2625 {
2626 	struct fw_ohci *ohci = fw_ohci(card);
2627 	unsigned long flags;
2628 
2629 	switch (csr_offset) {
2630 	case CSR_STATE_CLEAR:
2631 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2632 			reg_write(ohci, OHCI1394_LinkControlClear,
2633 				  OHCI1394_LinkControl_cycleMaster);
2634 			flush_writes(ohci);
2635 		}
2636 		if (value & CSR_STATE_BIT_ABDICATE)
2637 			ohci->csr_state_setclear_abdicate = false;
2638 		break;
2639 
2640 	case CSR_STATE_SET:
2641 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2642 			reg_write(ohci, OHCI1394_LinkControlSet,
2643 				  OHCI1394_LinkControl_cycleMaster);
2644 			flush_writes(ohci);
2645 		}
2646 		if (value & CSR_STATE_BIT_ABDICATE)
2647 			ohci->csr_state_setclear_abdicate = true;
2648 		break;
2649 
2650 	case CSR_NODE_IDS:
2651 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2652 		flush_writes(ohci);
2653 		break;
2654 
2655 	case CSR_CYCLE_TIME:
2656 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2657 		reg_write(ohci, OHCI1394_IntEventSet,
2658 			  OHCI1394_cycleInconsistent);
2659 		flush_writes(ohci);
2660 		break;
2661 
2662 	case CSR_BUS_TIME:
2663 		spin_lock_irqsave(&ohci->lock, flags);
2664 		ohci->bus_time = (ohci->bus_time & 0x7f) | (value & ~0x7f);
2665 		spin_unlock_irqrestore(&ohci->lock, flags);
2666 		break;
2667 
2668 	case CSR_BUSY_TIMEOUT:
2669 		value = (value & 0xf) | ((value & 0xf) << 4) |
2670 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2671 		reg_write(ohci, OHCI1394_ATRetries, value);
2672 		flush_writes(ohci);
2673 		break;
2674 
2675 	case CSR_PRIORITY_BUDGET:
2676 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2677 		flush_writes(ohci);
2678 		break;
2679 
2680 	default:
2681 		WARN_ON(1);
2682 		break;
2683 	}
2684 }
2685 
2686 static void flush_iso_completions(struct iso_context *ctx)
2687 {
2688 	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2689 			      ctx->header_length, ctx->header,
2690 			      ctx->base.callback_data);
2691 	ctx->header_length = 0;
2692 }
2693 
2694 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2695 {
2696 	u32 *ctx_hdr;
2697 
2698 	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE)
2699 		flush_iso_completions(ctx);
2700 
2701 	ctx_hdr = ctx->header + ctx->header_length;
2702 	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2703 
2704 	/*
2705 	 * The two iso header quadlets are byteswapped to little
2706 	 * endian by the controller, but we want to present them
2707 	 * as big endian for consistency with the bus endianness.
2708 	 */
2709 	if (ctx->base.header_size > 0)
2710 		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2711 	if (ctx->base.header_size > 4)
2712 		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2713 	if (ctx->base.header_size > 8)
2714 		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2715 	ctx->header_length += ctx->base.header_size;
2716 }
2717 
2718 static int handle_ir_packet_per_buffer(struct context *context,
2719 				       struct descriptor *d,
2720 				       struct descriptor *last)
2721 {
2722 	struct iso_context *ctx =
2723 		container_of(context, struct iso_context, context);
2724 	struct descriptor *pd;
2725 	u32 buffer_dma;
2726 
2727 	for (pd = d; pd <= last; pd++)
2728 		if (pd->transfer_status)
2729 			break;
2730 	if (pd > last)
2731 		/* Descriptor(s) not done yet, stop iteration */
2732 		return 0;
2733 
2734 	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2735 		d++;
2736 		buffer_dma = le32_to_cpu(d->data_address);
2737 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2738 					      buffer_dma & PAGE_MASK,
2739 					      buffer_dma & ~PAGE_MASK,
2740 					      le16_to_cpu(d->req_count),
2741 					      DMA_FROM_DEVICE);
2742 	}
2743 
2744 	copy_iso_headers(ctx, (u32 *) (last + 1));
2745 
2746 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2747 		flush_iso_completions(ctx);
2748 
2749 	return 1;
2750 }
2751 
2752 /* d == last because each descriptor block is only a single descriptor. */
2753 static int handle_ir_buffer_fill(struct context *context,
2754 				 struct descriptor *d,
2755 				 struct descriptor *last)
2756 {
2757 	struct iso_context *ctx =
2758 		container_of(context, struct iso_context, context);
2759 	unsigned int req_count, res_count, completed;
2760 	u32 buffer_dma;
2761 
2762 	req_count = le16_to_cpu(last->req_count);
2763 	res_count = le16_to_cpu(ACCESS_ONCE(last->res_count));
2764 	completed = req_count - res_count;
2765 	buffer_dma = le32_to_cpu(last->data_address);
2766 
2767 	if (completed > 0) {
2768 		ctx->mc_buffer_bus = buffer_dma;
2769 		ctx->mc_completed = completed;
2770 	}
2771 
2772 	if (res_count != 0)
2773 		/* Descriptor(s) not done yet, stop iteration */
2774 		return 0;
2775 
2776 	dma_sync_single_range_for_cpu(context->ohci->card.device,
2777 				      buffer_dma & PAGE_MASK,
2778 				      buffer_dma & ~PAGE_MASK,
2779 				      completed, DMA_FROM_DEVICE);
2780 
2781 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2782 		ctx->base.callback.mc(&ctx->base,
2783 				      buffer_dma + completed,
2784 				      ctx->base.callback_data);
2785 		ctx->mc_completed = 0;
2786 	}
2787 
2788 	return 1;
2789 }
2790 
2791 static void flush_ir_buffer_fill(struct iso_context *ctx)
2792 {
2793 	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
2794 				      ctx->mc_buffer_bus & PAGE_MASK,
2795 				      ctx->mc_buffer_bus & ~PAGE_MASK,
2796 				      ctx->mc_completed, DMA_FROM_DEVICE);
2797 
2798 	ctx->base.callback.mc(&ctx->base,
2799 			      ctx->mc_buffer_bus + ctx->mc_completed,
2800 			      ctx->base.callback_data);
2801 	ctx->mc_completed = 0;
2802 }
2803 
2804 static inline void sync_it_packet_for_cpu(struct context *context,
2805 					  struct descriptor *pd)
2806 {
2807 	__le16 control;
2808 	u32 buffer_dma;
2809 
2810 	/* only packets beginning with OUTPUT_MORE* have data buffers */
2811 	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2812 		return;
2813 
2814 	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
2815 	pd += 2;
2816 
2817 	/*
2818 	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
2819 	 * data buffer is in the context program's coherent page and must not
2820 	 * be synced.
2821 	 */
2822 	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
2823 	    (context->current_bus          & PAGE_MASK)) {
2824 		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2825 			return;
2826 		pd++;
2827 	}
2828 
2829 	do {
2830 		buffer_dma = le32_to_cpu(pd->data_address);
2831 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2832 					      buffer_dma & PAGE_MASK,
2833 					      buffer_dma & ~PAGE_MASK,
2834 					      le16_to_cpu(pd->req_count),
2835 					      DMA_TO_DEVICE);
2836 		control = pd->control;
2837 		pd++;
2838 	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
2839 }
2840 
2841 static int handle_it_packet(struct context *context,
2842 			    struct descriptor *d,
2843 			    struct descriptor *last)
2844 {
2845 	struct iso_context *ctx =
2846 		container_of(context, struct iso_context, context);
2847 	struct descriptor *pd;
2848 	__be32 *ctx_hdr;
2849 
2850 	for (pd = d; pd <= last; pd++)
2851 		if (pd->transfer_status)
2852 			break;
2853 	if (pd > last)
2854 		/* Descriptor(s) not done yet, stop iteration */
2855 		return 0;
2856 
2857 	sync_it_packet_for_cpu(context, d);
2858 
2859 	if (ctx->header_length + 4 > PAGE_SIZE)
2860 		flush_iso_completions(ctx);
2861 
2862 	ctx_hdr = ctx->header + ctx->header_length;
2863 	ctx->last_timestamp = le16_to_cpu(last->res_count);
2864 	/* Present this value as big-endian to match the receive code */
2865 	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
2866 			       le16_to_cpu(pd->res_count));
2867 	ctx->header_length += 4;
2868 
2869 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2870 		flush_iso_completions(ctx);
2871 
2872 	return 1;
2873 }
2874 
2875 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2876 {
2877 	u32 hi = channels >> 32, lo = channels;
2878 
2879 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2880 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2881 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2882 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2883 	mmiowb();
2884 	ohci->mc_channels = channels;
2885 }
2886 
2887 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2888 				int type, int channel, size_t header_size)
2889 {
2890 	struct fw_ohci *ohci = fw_ohci(card);
2891 	struct iso_context *uninitialized_var(ctx);
2892 	descriptor_callback_t uninitialized_var(callback);
2893 	u64 *uninitialized_var(channels);
2894 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2895 	unsigned long flags;
2896 	int index, ret = -EBUSY;
2897 
2898 	spin_lock_irqsave(&ohci->lock, flags);
2899 
2900 	switch (type) {
2901 	case FW_ISO_CONTEXT_TRANSMIT:
2902 		mask     = &ohci->it_context_mask;
2903 		callback = handle_it_packet;
2904 		index    = ffs(*mask) - 1;
2905 		if (index >= 0) {
2906 			*mask &= ~(1 << index);
2907 			regs = OHCI1394_IsoXmitContextBase(index);
2908 			ctx  = &ohci->it_context_list[index];
2909 		}
2910 		break;
2911 
2912 	case FW_ISO_CONTEXT_RECEIVE:
2913 		channels = &ohci->ir_context_channels;
2914 		mask     = &ohci->ir_context_mask;
2915 		callback = handle_ir_packet_per_buffer;
2916 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2917 		if (index >= 0) {
2918 			*channels &= ~(1ULL << channel);
2919 			*mask     &= ~(1 << index);
2920 			regs = OHCI1394_IsoRcvContextBase(index);
2921 			ctx  = &ohci->ir_context_list[index];
2922 		}
2923 		break;
2924 
2925 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2926 		mask     = &ohci->ir_context_mask;
2927 		callback = handle_ir_buffer_fill;
2928 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2929 		if (index >= 0) {
2930 			ohci->mc_allocated = true;
2931 			*mask &= ~(1 << index);
2932 			regs = OHCI1394_IsoRcvContextBase(index);
2933 			ctx  = &ohci->ir_context_list[index];
2934 		}
2935 		break;
2936 
2937 	default:
2938 		index = -1;
2939 		ret = -ENOSYS;
2940 	}
2941 
2942 	spin_unlock_irqrestore(&ohci->lock, flags);
2943 
2944 	if (index < 0)
2945 		return ERR_PTR(ret);
2946 
2947 	memset(ctx, 0, sizeof(*ctx));
2948 	ctx->header_length = 0;
2949 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2950 	if (ctx->header == NULL) {
2951 		ret = -ENOMEM;
2952 		goto out;
2953 	}
2954 	ret = context_init(&ctx->context, ohci, regs, callback);
2955 	if (ret < 0)
2956 		goto out_with_header;
2957 
2958 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
2959 		set_multichannel_mask(ohci, 0);
2960 		ctx->mc_completed = 0;
2961 	}
2962 
2963 	return &ctx->base;
2964 
2965  out_with_header:
2966 	free_page((unsigned long)ctx->header);
2967  out:
2968 	spin_lock_irqsave(&ohci->lock, flags);
2969 
2970 	switch (type) {
2971 	case FW_ISO_CONTEXT_RECEIVE:
2972 		*channels |= 1ULL << channel;
2973 		break;
2974 
2975 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2976 		ohci->mc_allocated = false;
2977 		break;
2978 	}
2979 	*mask |= 1 << index;
2980 
2981 	spin_unlock_irqrestore(&ohci->lock, flags);
2982 
2983 	return ERR_PTR(ret);
2984 }
2985 
2986 static int ohci_start_iso(struct fw_iso_context *base,
2987 			  s32 cycle, u32 sync, u32 tags)
2988 {
2989 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2990 	struct fw_ohci *ohci = ctx->context.ohci;
2991 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2992 	int index;
2993 
2994 	/* the controller cannot start without any queued packets */
2995 	if (ctx->context.last->branch_address == 0)
2996 		return -ENODATA;
2997 
2998 	switch (ctx->base.type) {
2999 	case FW_ISO_CONTEXT_TRANSMIT:
3000 		index = ctx - ohci->it_context_list;
3001 		match = 0;
3002 		if (cycle >= 0)
3003 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3004 				(cycle & 0x7fff) << 16;
3005 
3006 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3007 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3008 		context_run(&ctx->context, match);
3009 		break;
3010 
3011 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3012 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3013 		/* fall through */
3014 	case FW_ISO_CONTEXT_RECEIVE:
3015 		index = ctx - ohci->ir_context_list;
3016 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
3017 		if (cycle >= 0) {
3018 			match |= (cycle & 0x07fff) << 12;
3019 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3020 		}
3021 
3022 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3023 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3024 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3025 		context_run(&ctx->context, control);
3026 
3027 		ctx->sync = sync;
3028 		ctx->tags = tags;
3029 
3030 		break;
3031 	}
3032 
3033 	return 0;
3034 }
3035 
3036 static int ohci_stop_iso(struct fw_iso_context *base)
3037 {
3038 	struct fw_ohci *ohci = fw_ohci(base->card);
3039 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3040 	int index;
3041 
3042 	switch (ctx->base.type) {
3043 	case FW_ISO_CONTEXT_TRANSMIT:
3044 		index = ctx - ohci->it_context_list;
3045 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3046 		break;
3047 
3048 	case FW_ISO_CONTEXT_RECEIVE:
3049 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3050 		index = ctx - ohci->ir_context_list;
3051 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3052 		break;
3053 	}
3054 	flush_writes(ohci);
3055 	context_stop(&ctx->context);
3056 	tasklet_kill(&ctx->context.tasklet);
3057 
3058 	return 0;
3059 }
3060 
3061 static void ohci_free_iso_context(struct fw_iso_context *base)
3062 {
3063 	struct fw_ohci *ohci = fw_ohci(base->card);
3064 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3065 	unsigned long flags;
3066 	int index;
3067 
3068 	ohci_stop_iso(base);
3069 	context_release(&ctx->context);
3070 	free_page((unsigned long)ctx->header);
3071 
3072 	spin_lock_irqsave(&ohci->lock, flags);
3073 
3074 	switch (base->type) {
3075 	case FW_ISO_CONTEXT_TRANSMIT:
3076 		index = ctx - ohci->it_context_list;
3077 		ohci->it_context_mask |= 1 << index;
3078 		break;
3079 
3080 	case FW_ISO_CONTEXT_RECEIVE:
3081 		index = ctx - ohci->ir_context_list;
3082 		ohci->ir_context_mask |= 1 << index;
3083 		ohci->ir_context_channels |= 1ULL << base->channel;
3084 		break;
3085 
3086 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3087 		index = ctx - ohci->ir_context_list;
3088 		ohci->ir_context_mask |= 1 << index;
3089 		ohci->ir_context_channels |= ohci->mc_channels;
3090 		ohci->mc_channels = 0;
3091 		ohci->mc_allocated = false;
3092 		break;
3093 	}
3094 
3095 	spin_unlock_irqrestore(&ohci->lock, flags);
3096 }
3097 
3098 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3099 {
3100 	struct fw_ohci *ohci = fw_ohci(base->card);
3101 	unsigned long flags;
3102 	int ret;
3103 
3104 	switch (base->type) {
3105 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3106 
3107 		spin_lock_irqsave(&ohci->lock, flags);
3108 
3109 		/* Don't allow multichannel to grab other contexts' channels. */
3110 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3111 			*channels = ohci->ir_context_channels;
3112 			ret = -EBUSY;
3113 		} else {
3114 			set_multichannel_mask(ohci, *channels);
3115 			ret = 0;
3116 		}
3117 
3118 		spin_unlock_irqrestore(&ohci->lock, flags);
3119 
3120 		break;
3121 	default:
3122 		ret = -EINVAL;
3123 	}
3124 
3125 	return ret;
3126 }
3127 
3128 #ifdef CONFIG_PM
3129 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3130 {
3131 	int i;
3132 	struct iso_context *ctx;
3133 
3134 	for (i = 0 ; i < ohci->n_ir ; i++) {
3135 		ctx = &ohci->ir_context_list[i];
3136 		if (ctx->context.running)
3137 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3138 	}
3139 
3140 	for (i = 0 ; i < ohci->n_it ; i++) {
3141 		ctx = &ohci->it_context_list[i];
3142 		if (ctx->context.running)
3143 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3144 	}
3145 }
3146 #endif
3147 
3148 static int queue_iso_transmit(struct iso_context *ctx,
3149 			      struct fw_iso_packet *packet,
3150 			      struct fw_iso_buffer *buffer,
3151 			      unsigned long payload)
3152 {
3153 	struct descriptor *d, *last, *pd;
3154 	struct fw_iso_packet *p;
3155 	__le32 *header;
3156 	dma_addr_t d_bus, page_bus;
3157 	u32 z, header_z, payload_z, irq;
3158 	u32 payload_index, payload_end_index, next_page_index;
3159 	int page, end_page, i, length, offset;
3160 
3161 	p = packet;
3162 	payload_index = payload;
3163 
3164 	if (p->skip)
3165 		z = 1;
3166 	else
3167 		z = 2;
3168 	if (p->header_length > 0)
3169 		z++;
3170 
3171 	/* Determine the first page the payload isn't contained in. */
3172 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3173 	if (p->payload_length > 0)
3174 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
3175 	else
3176 		payload_z = 0;
3177 
3178 	z += payload_z;
3179 
3180 	/* Get header size in number of descriptors. */
3181 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3182 
3183 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3184 	if (d == NULL)
3185 		return -ENOMEM;
3186 
3187 	if (!p->skip) {
3188 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3189 		d[0].req_count = cpu_to_le16(8);
3190 		/*
3191 		 * Link the skip address to this descriptor itself.  This causes
3192 		 * a context to skip a cycle whenever lost cycles or FIFO
3193 		 * overruns occur, without dropping the data.  The application
3194 		 * should then decide whether this is an error condition or not.
3195 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
3196 		 */
3197 		d[0].branch_address = cpu_to_le32(d_bus | z);
3198 
3199 		header = (__le32 *) &d[1];
3200 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
3201 					IT_HEADER_TAG(p->tag) |
3202 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
3203 					IT_HEADER_CHANNEL(ctx->base.channel) |
3204 					IT_HEADER_SPEED(ctx->base.speed));
3205 		header[1] =
3206 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
3207 							  p->payload_length));
3208 	}
3209 
3210 	if (p->header_length > 0) {
3211 		d[2].req_count    = cpu_to_le16(p->header_length);
3212 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3213 		memcpy(&d[z], p->header, p->header_length);
3214 	}
3215 
3216 	pd = d + z - payload_z;
3217 	payload_end_index = payload_index + p->payload_length;
3218 	for (i = 0; i < payload_z; i++) {
3219 		page               = payload_index >> PAGE_SHIFT;
3220 		offset             = payload_index & ~PAGE_MASK;
3221 		next_page_index    = (page + 1) << PAGE_SHIFT;
3222 		length             =
3223 			min(next_page_index, payload_end_index) - payload_index;
3224 		pd[i].req_count    = cpu_to_le16(length);
3225 
3226 		page_bus = page_private(buffer->pages[page]);
3227 		pd[i].data_address = cpu_to_le32(page_bus + offset);
3228 
3229 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3230 						 page_bus, offset, length,
3231 						 DMA_TO_DEVICE);
3232 
3233 		payload_index += length;
3234 	}
3235 
3236 	if (p->interrupt)
3237 		irq = DESCRIPTOR_IRQ_ALWAYS;
3238 	else
3239 		irq = DESCRIPTOR_NO_IRQ;
3240 
3241 	last = z == 2 ? d : d + z - 1;
3242 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3243 				     DESCRIPTOR_STATUS |
3244 				     DESCRIPTOR_BRANCH_ALWAYS |
3245 				     irq);
3246 
3247 	context_append(&ctx->context, d, z, header_z);
3248 
3249 	return 0;
3250 }
3251 
3252 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3253 				       struct fw_iso_packet *packet,
3254 				       struct fw_iso_buffer *buffer,
3255 				       unsigned long payload)
3256 {
3257 	struct device *device = ctx->context.ohci->card.device;
3258 	struct descriptor *d, *pd;
3259 	dma_addr_t d_bus, page_bus;
3260 	u32 z, header_z, rest;
3261 	int i, j, length;
3262 	int page, offset, packet_count, header_size, payload_per_buffer;
3263 
3264 	/*
3265 	 * The OHCI controller puts the isochronous header and trailer in the
3266 	 * buffer, so we need at least 8 bytes.
3267 	 */
3268 	packet_count = packet->header_length / ctx->base.header_size;
3269 	header_size  = max(ctx->base.header_size, (size_t)8);
3270 
3271 	/* Get header size in number of descriptors. */
3272 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3273 	page     = payload >> PAGE_SHIFT;
3274 	offset   = payload & ~PAGE_MASK;
3275 	payload_per_buffer = packet->payload_length / packet_count;
3276 
3277 	for (i = 0; i < packet_count; i++) {
3278 		/* d points to the header descriptor */
3279 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3280 		d = context_get_descriptors(&ctx->context,
3281 				z + header_z, &d_bus);
3282 		if (d == NULL)
3283 			return -ENOMEM;
3284 
3285 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3286 					      DESCRIPTOR_INPUT_MORE);
3287 		if (packet->skip && i == 0)
3288 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3289 		d->req_count    = cpu_to_le16(header_size);
3290 		d->res_count    = d->req_count;
3291 		d->transfer_status = 0;
3292 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3293 
3294 		rest = payload_per_buffer;
3295 		pd = d;
3296 		for (j = 1; j < z; j++) {
3297 			pd++;
3298 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3299 						  DESCRIPTOR_INPUT_MORE);
3300 
3301 			if (offset + rest < PAGE_SIZE)
3302 				length = rest;
3303 			else
3304 				length = PAGE_SIZE - offset;
3305 			pd->req_count = cpu_to_le16(length);
3306 			pd->res_count = pd->req_count;
3307 			pd->transfer_status = 0;
3308 
3309 			page_bus = page_private(buffer->pages[page]);
3310 			pd->data_address = cpu_to_le32(page_bus + offset);
3311 
3312 			dma_sync_single_range_for_device(device, page_bus,
3313 							 offset, length,
3314 							 DMA_FROM_DEVICE);
3315 
3316 			offset = (offset + length) & ~PAGE_MASK;
3317 			rest -= length;
3318 			if (offset == 0)
3319 				page++;
3320 		}
3321 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3322 					  DESCRIPTOR_INPUT_LAST |
3323 					  DESCRIPTOR_BRANCH_ALWAYS);
3324 		if (packet->interrupt && i == packet_count - 1)
3325 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3326 
3327 		context_append(&ctx->context, d, z, header_z);
3328 	}
3329 
3330 	return 0;
3331 }
3332 
3333 static int queue_iso_buffer_fill(struct iso_context *ctx,
3334 				 struct fw_iso_packet *packet,
3335 				 struct fw_iso_buffer *buffer,
3336 				 unsigned long payload)
3337 {
3338 	struct descriptor *d;
3339 	dma_addr_t d_bus, page_bus;
3340 	int page, offset, rest, z, i, length;
3341 
3342 	page   = payload >> PAGE_SHIFT;
3343 	offset = payload & ~PAGE_MASK;
3344 	rest   = packet->payload_length;
3345 
3346 	/* We need one descriptor for each page in the buffer. */
3347 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3348 
3349 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3350 		return -EFAULT;
3351 
3352 	for (i = 0; i < z; i++) {
3353 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3354 		if (d == NULL)
3355 			return -ENOMEM;
3356 
3357 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3358 					 DESCRIPTOR_BRANCH_ALWAYS);
3359 		if (packet->skip && i == 0)
3360 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3361 		if (packet->interrupt && i == z - 1)
3362 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3363 
3364 		if (offset + rest < PAGE_SIZE)
3365 			length = rest;
3366 		else
3367 			length = PAGE_SIZE - offset;
3368 		d->req_count = cpu_to_le16(length);
3369 		d->res_count = d->req_count;
3370 		d->transfer_status = 0;
3371 
3372 		page_bus = page_private(buffer->pages[page]);
3373 		d->data_address = cpu_to_le32(page_bus + offset);
3374 
3375 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3376 						 page_bus, offset, length,
3377 						 DMA_FROM_DEVICE);
3378 
3379 		rest -= length;
3380 		offset = 0;
3381 		page++;
3382 
3383 		context_append(&ctx->context, d, 1, 0);
3384 	}
3385 
3386 	return 0;
3387 }
3388 
3389 static int ohci_queue_iso(struct fw_iso_context *base,
3390 			  struct fw_iso_packet *packet,
3391 			  struct fw_iso_buffer *buffer,
3392 			  unsigned long payload)
3393 {
3394 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3395 	unsigned long flags;
3396 	int ret = -ENOSYS;
3397 
3398 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3399 	switch (base->type) {
3400 	case FW_ISO_CONTEXT_TRANSMIT:
3401 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
3402 		break;
3403 	case FW_ISO_CONTEXT_RECEIVE:
3404 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3405 		break;
3406 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3407 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3408 		break;
3409 	}
3410 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3411 
3412 	return ret;
3413 }
3414 
3415 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3416 {
3417 	struct context *ctx =
3418 			&container_of(base, struct iso_context, base)->context;
3419 
3420 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3421 }
3422 
3423 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3424 {
3425 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3426 	int ret = 0;
3427 
3428 	tasklet_disable(&ctx->context.tasklet);
3429 
3430 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3431 		context_tasklet((unsigned long)&ctx->context);
3432 
3433 		switch (base->type) {
3434 		case FW_ISO_CONTEXT_TRANSMIT:
3435 		case FW_ISO_CONTEXT_RECEIVE:
3436 			if (ctx->header_length != 0)
3437 				flush_iso_completions(ctx);
3438 			break;
3439 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3440 			if (ctx->mc_completed != 0)
3441 				flush_ir_buffer_fill(ctx);
3442 			break;
3443 		default:
3444 			ret = -ENOSYS;
3445 		}
3446 
3447 		clear_bit_unlock(0, &ctx->flushing_completions);
3448 		smp_mb__after_clear_bit();
3449 	}
3450 
3451 	tasklet_enable(&ctx->context.tasklet);
3452 
3453 	return ret;
3454 }
3455 
3456 static const struct fw_card_driver ohci_driver = {
3457 	.enable			= ohci_enable,
3458 	.read_phy_reg		= ohci_read_phy_reg,
3459 	.update_phy_reg		= ohci_update_phy_reg,
3460 	.set_config_rom		= ohci_set_config_rom,
3461 	.send_request		= ohci_send_request,
3462 	.send_response		= ohci_send_response,
3463 	.cancel_packet		= ohci_cancel_packet,
3464 	.enable_phys_dma	= ohci_enable_phys_dma,
3465 	.read_csr		= ohci_read_csr,
3466 	.write_csr		= ohci_write_csr,
3467 
3468 	.allocate_iso_context	= ohci_allocate_iso_context,
3469 	.free_iso_context	= ohci_free_iso_context,
3470 	.set_iso_channels	= ohci_set_iso_channels,
3471 	.queue_iso		= ohci_queue_iso,
3472 	.flush_queue_iso	= ohci_flush_queue_iso,
3473 	.flush_iso_completions	= ohci_flush_iso_completions,
3474 	.start_iso		= ohci_start_iso,
3475 	.stop_iso		= ohci_stop_iso,
3476 };
3477 
3478 #ifdef CONFIG_PPC_PMAC
3479 static void pmac_ohci_on(struct pci_dev *dev)
3480 {
3481 	if (machine_is(powermac)) {
3482 		struct device_node *ofn = pci_device_to_OF_node(dev);
3483 
3484 		if (ofn) {
3485 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3486 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3487 		}
3488 	}
3489 }
3490 
3491 static void pmac_ohci_off(struct pci_dev *dev)
3492 {
3493 	if (machine_is(powermac)) {
3494 		struct device_node *ofn = pci_device_to_OF_node(dev);
3495 
3496 		if (ofn) {
3497 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3498 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3499 		}
3500 	}
3501 }
3502 #else
3503 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3504 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3505 #endif /* CONFIG_PPC_PMAC */
3506 
3507 static int __devinit pci_probe(struct pci_dev *dev,
3508 			       const struct pci_device_id *ent)
3509 {
3510 	struct fw_ohci *ohci;
3511 	u32 bus_options, max_receive, link_speed, version;
3512 	u64 guid;
3513 	int i, err;
3514 	size_t size;
3515 
3516 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3517 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3518 		return -ENOSYS;
3519 	}
3520 
3521 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3522 	if (ohci == NULL) {
3523 		err = -ENOMEM;
3524 		goto fail;
3525 	}
3526 
3527 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3528 
3529 	pmac_ohci_on(dev);
3530 
3531 	err = pci_enable_device(dev);
3532 	if (err) {
3533 		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3534 		goto fail_free;
3535 	}
3536 
3537 	pci_set_master(dev);
3538 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3539 	pci_set_drvdata(dev, ohci);
3540 
3541 	spin_lock_init(&ohci->lock);
3542 	mutex_init(&ohci->phy_reg_mutex);
3543 
3544 	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3545 
3546 	err = pci_request_region(dev, 0, ohci_driver_name);
3547 	if (err) {
3548 		dev_err(&dev->dev, "MMIO resource unavailable\n");
3549 		goto fail_disable;
3550 	}
3551 
3552 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3553 	if (ohci->registers == NULL) {
3554 		dev_err(&dev->dev, "failed to remap registers\n");
3555 		err = -ENXIO;
3556 		goto fail_iomem;
3557 	}
3558 
3559 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3560 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3561 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3562 		     ohci_quirks[i].device == dev->device) &&
3563 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3564 		     ohci_quirks[i].revision >= dev->revision)) {
3565 			ohci->quirks = ohci_quirks[i].flags;
3566 			break;
3567 		}
3568 	if (param_quirks)
3569 		ohci->quirks = param_quirks;
3570 
3571 	/*
3572 	 * Because dma_alloc_coherent() allocates at least one page,
3573 	 * we save space by using a common buffer for the AR request/
3574 	 * response descriptors and the self IDs buffer.
3575 	 */
3576 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3577 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3578 	ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3579 					       PAGE_SIZE,
3580 					       &ohci->misc_buffer_bus,
3581 					       GFP_KERNEL);
3582 	if (!ohci->misc_buffer) {
3583 		err = -ENOMEM;
3584 		goto fail_iounmap;
3585 	}
3586 
3587 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3588 			      OHCI1394_AsReqRcvContextControlSet);
3589 	if (err < 0)
3590 		goto fail_misc_buf;
3591 
3592 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3593 			      OHCI1394_AsRspRcvContextControlSet);
3594 	if (err < 0)
3595 		goto fail_arreq_ctx;
3596 
3597 	err = context_init(&ohci->at_request_ctx, ohci,
3598 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3599 	if (err < 0)
3600 		goto fail_arrsp_ctx;
3601 
3602 	err = context_init(&ohci->at_response_ctx, ohci,
3603 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3604 	if (err < 0)
3605 		goto fail_atreq_ctx;
3606 
3607 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3608 	ohci->ir_context_channels = ~0ULL;
3609 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3610 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3611 	ohci->ir_context_mask = ohci->ir_context_support;
3612 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3613 	size = sizeof(struct iso_context) * ohci->n_ir;
3614 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3615 
3616 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3617 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3618 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3619 	ohci->it_context_mask = ohci->it_context_support;
3620 	ohci->n_it = hweight32(ohci->it_context_mask);
3621 	size = sizeof(struct iso_context) * ohci->n_it;
3622 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3623 
3624 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3625 		err = -ENOMEM;
3626 		goto fail_contexts;
3627 	}
3628 
3629 	ohci->self_id_cpu = ohci->misc_buffer     + PAGE_SIZE/2;
3630 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3631 
3632 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3633 	max_receive = (bus_options >> 12) & 0xf;
3634 	link_speed = bus_options & 0x7;
3635 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3636 		reg_read(ohci, OHCI1394_GUIDLo);
3637 
3638 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3639 	if (err)
3640 		goto fail_contexts;
3641 
3642 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3643 	dev_notice(&dev->dev,
3644 		  "added OHCI v%x.%x device as card %d, "
3645 		  "%d IR + %d IT contexts, quirks 0x%x\n",
3646 		  version >> 16, version & 0xff, ohci->card.index,
3647 		  ohci->n_ir, ohci->n_it, ohci->quirks);
3648 
3649 	return 0;
3650 
3651  fail_contexts:
3652 	kfree(ohci->ir_context_list);
3653 	kfree(ohci->it_context_list);
3654 	context_release(&ohci->at_response_ctx);
3655  fail_atreq_ctx:
3656 	context_release(&ohci->at_request_ctx);
3657  fail_arrsp_ctx:
3658 	ar_context_release(&ohci->ar_response_ctx);
3659  fail_arreq_ctx:
3660 	ar_context_release(&ohci->ar_request_ctx);
3661  fail_misc_buf:
3662 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3663 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3664  fail_iounmap:
3665 	pci_iounmap(dev, ohci->registers);
3666  fail_iomem:
3667 	pci_release_region(dev, 0);
3668  fail_disable:
3669 	pci_disable_device(dev);
3670  fail_free:
3671 	kfree(ohci);
3672 	pmac_ohci_off(dev);
3673  fail:
3674 	if (err == -ENOMEM)
3675 		dev_err(&dev->dev, "out of memory\n");
3676 
3677 	return err;
3678 }
3679 
3680 static void pci_remove(struct pci_dev *dev)
3681 {
3682 	struct fw_ohci *ohci;
3683 
3684 	ohci = pci_get_drvdata(dev);
3685 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3686 	flush_writes(ohci);
3687 	cancel_work_sync(&ohci->bus_reset_work);
3688 	fw_core_remove_card(&ohci->card);
3689 
3690 	/*
3691 	 * FIXME: Fail all pending packets here, now that the upper
3692 	 * layers can't queue any more.
3693 	 */
3694 
3695 	software_reset(ohci);
3696 	free_irq(dev->irq, ohci);
3697 
3698 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3699 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3700 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3701 	if (ohci->config_rom)
3702 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3703 				  ohci->config_rom, ohci->config_rom_bus);
3704 	ar_context_release(&ohci->ar_request_ctx);
3705 	ar_context_release(&ohci->ar_response_ctx);
3706 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3707 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3708 	context_release(&ohci->at_request_ctx);
3709 	context_release(&ohci->at_response_ctx);
3710 	kfree(ohci->it_context_list);
3711 	kfree(ohci->ir_context_list);
3712 	pci_disable_msi(dev);
3713 	pci_iounmap(dev, ohci->registers);
3714 	pci_release_region(dev, 0);
3715 	pci_disable_device(dev);
3716 	kfree(ohci);
3717 	pmac_ohci_off(dev);
3718 
3719 	dev_notice(&dev->dev, "removed fw-ohci device\n");
3720 }
3721 
3722 #ifdef CONFIG_PM
3723 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3724 {
3725 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3726 	int err;
3727 
3728 	software_reset(ohci);
3729 	free_irq(dev->irq, ohci);
3730 	pci_disable_msi(dev);
3731 	err = pci_save_state(dev);
3732 	if (err) {
3733 		dev_err(&dev->dev, "pci_save_state failed\n");
3734 		return err;
3735 	}
3736 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3737 	if (err)
3738 		dev_err(&dev->dev, "pci_set_power_state failed with %d\n", err);
3739 	pmac_ohci_off(dev);
3740 
3741 	return 0;
3742 }
3743 
3744 static int pci_resume(struct pci_dev *dev)
3745 {
3746 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3747 	int err;
3748 
3749 	pmac_ohci_on(dev);
3750 	pci_set_power_state(dev, PCI_D0);
3751 	pci_restore_state(dev);
3752 	err = pci_enable_device(dev);
3753 	if (err) {
3754 		dev_err(&dev->dev, "pci_enable_device failed\n");
3755 		return err;
3756 	}
3757 
3758 	/* Some systems don't setup GUID register on resume from ram  */
3759 	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3760 					!reg_read(ohci, OHCI1394_GUIDHi)) {
3761 		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3762 		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3763 	}
3764 
3765 	err = ohci_enable(&ohci->card, NULL, 0);
3766 	if (err)
3767 		return err;
3768 
3769 	ohci_resume_iso_dma(ohci);
3770 
3771 	return 0;
3772 }
3773 #endif
3774 
3775 static const struct pci_device_id pci_table[] = {
3776 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3777 	{ }
3778 };
3779 
3780 MODULE_DEVICE_TABLE(pci, pci_table);
3781 
3782 static struct pci_driver fw_ohci_pci_driver = {
3783 	.name		= ohci_driver_name,
3784 	.id_table	= pci_table,
3785 	.probe		= pci_probe,
3786 	.remove		= pci_remove,
3787 #ifdef CONFIG_PM
3788 	.resume		= pci_resume,
3789 	.suspend	= pci_suspend,
3790 #endif
3791 };
3792 
3793 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3794 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3795 MODULE_LICENSE("GPL");
3796 
3797 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3798 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3799 MODULE_ALIAS("ohci1394");
3800 #endif
3801 
3802 static int __init fw_ohci_init(void)
3803 {
3804 	return pci_register_driver(&fw_ohci_pci_driver);
3805 }
3806 
3807 static void __exit fw_ohci_cleanup(void)
3808 {
3809 	pci_unregister_driver(&fw_ohci_pci_driver);
3810 }
3811 
3812 module_init(fw_ohci_init);
3813 module_exit(fw_ohci_cleanup);
3814