xref: /linux/drivers/firewire/ohci.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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/bug.h>
22 #include <linux/compiler.h>
23 #include <linux/delay.h>
24 #include <linux/device.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/firewire.h>
27 #include <linux/firewire-constants.h>
28 #include <linux/init.h>
29 #include <linux/interrupt.h>
30 #include <linux/io.h>
31 #include <linux/kernel.h>
32 #include <linux/list.h>
33 #include <linux/mm.h>
34 #include <linux/module.h>
35 #include <linux/moduleparam.h>
36 #include <linux/mutex.h>
37 #include <linux/pci.h>
38 #include <linux/pci_ids.h>
39 #include <linux/slab.h>
40 #include <linux/spinlock.h>
41 #include <linux/string.h>
42 #include <linux/time.h>
43 
44 #include <asm/byteorder.h>
45 #include <asm/page.h>
46 #include <asm/system.h>
47 
48 #ifdef CONFIG_PPC_PMAC
49 #include <asm/pmac_feature.h>
50 #endif
51 
52 #include "core.h"
53 #include "ohci.h"
54 
55 #define DESCRIPTOR_OUTPUT_MORE		0
56 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
57 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
58 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
59 #define DESCRIPTOR_STATUS		(1 << 11)
60 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
61 #define DESCRIPTOR_PING			(1 << 7)
62 #define DESCRIPTOR_YY			(1 << 6)
63 #define DESCRIPTOR_NO_IRQ		(0 << 4)
64 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
65 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
66 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
67 #define DESCRIPTOR_WAIT			(3 << 0)
68 
69 struct descriptor {
70 	__le16 req_count;
71 	__le16 control;
72 	__le32 data_address;
73 	__le32 branch_address;
74 	__le16 res_count;
75 	__le16 transfer_status;
76 } __attribute__((aligned(16)));
77 
78 #define CONTROL_SET(regs)	(regs)
79 #define CONTROL_CLEAR(regs)	((regs) + 4)
80 #define COMMAND_PTR(regs)	((regs) + 12)
81 #define CONTEXT_MATCH(regs)	((regs) + 16)
82 
83 struct ar_buffer {
84 	struct descriptor descriptor;
85 	struct ar_buffer *next;
86 	__le32 data[0];
87 };
88 
89 struct ar_context {
90 	struct fw_ohci *ohci;
91 	struct ar_buffer *current_buffer;
92 	struct ar_buffer *last_buffer;
93 	void *pointer;
94 	u32 regs;
95 	struct tasklet_struct tasklet;
96 };
97 
98 struct context;
99 
100 typedef int (*descriptor_callback_t)(struct context *ctx,
101 				     struct descriptor *d,
102 				     struct descriptor *last);
103 
104 /*
105  * A buffer that contains a block of DMA-able coherent memory used for
106  * storing a portion of a DMA descriptor program.
107  */
108 struct descriptor_buffer {
109 	struct list_head list;
110 	dma_addr_t buffer_bus;
111 	size_t buffer_size;
112 	size_t used;
113 	struct descriptor buffer[0];
114 };
115 
116 struct context {
117 	struct fw_ohci *ohci;
118 	u32 regs;
119 	int total_allocation;
120 
121 	/*
122 	 * List of page-sized buffers for storing DMA descriptors.
123 	 * Head of list contains buffers in use and tail of list contains
124 	 * free buffers.
125 	 */
126 	struct list_head buffer_list;
127 
128 	/*
129 	 * Pointer to a buffer inside buffer_list that contains the tail
130 	 * end of the current DMA program.
131 	 */
132 	struct descriptor_buffer *buffer_tail;
133 
134 	/*
135 	 * The descriptor containing the branch address of the first
136 	 * descriptor that has not yet been filled by the device.
137 	 */
138 	struct descriptor *last;
139 
140 	/*
141 	 * The last descriptor in the DMA program.  It contains the branch
142 	 * address that must be updated upon appending a new descriptor.
143 	 */
144 	struct descriptor *prev;
145 
146 	descriptor_callback_t callback;
147 
148 	struct tasklet_struct tasklet;
149 };
150 
151 #define IT_HEADER_SY(v)          ((v) <<  0)
152 #define IT_HEADER_TCODE(v)       ((v) <<  4)
153 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
154 #define IT_HEADER_TAG(v)         ((v) << 14)
155 #define IT_HEADER_SPEED(v)       ((v) << 16)
156 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
157 
158 struct iso_context {
159 	struct fw_iso_context base;
160 	struct context context;
161 	int excess_bytes;
162 	void *header;
163 	size_t header_length;
164 };
165 
166 #define CONFIG_ROM_SIZE 1024
167 
168 struct fw_ohci {
169 	struct fw_card card;
170 
171 	__iomem char *registers;
172 	int node_id;
173 	int generation;
174 	int request_generation;	/* for timestamping incoming requests */
175 	unsigned quirks;
176 	unsigned int pri_req_max;
177 	u32 bus_time;
178 	bool is_root;
179 	bool csr_state_setclear_abdicate;
180 
181 	/*
182 	 * Spinlock for accessing fw_ohci data.  Never call out of
183 	 * this driver with this lock held.
184 	 */
185 	spinlock_t lock;
186 
187 	struct mutex phy_reg_mutex;
188 
189 	struct ar_context ar_request_ctx;
190 	struct ar_context ar_response_ctx;
191 	struct context at_request_ctx;
192 	struct context at_response_ctx;
193 
194 	u32 it_context_mask;     /* unoccupied IT contexts */
195 	struct iso_context *it_context_list;
196 	u64 ir_context_channels; /* unoccupied channels */
197 	u32 ir_context_mask;     /* unoccupied IR contexts */
198 	struct iso_context *ir_context_list;
199 	u64 mc_channels; /* channels in use by the multichannel IR context */
200 	bool mc_allocated;
201 
202 	__be32    *config_rom;
203 	dma_addr_t config_rom_bus;
204 	__be32    *next_config_rom;
205 	dma_addr_t next_config_rom_bus;
206 	__be32     next_header;
207 
208 	__le32    *self_id_cpu;
209 	dma_addr_t self_id_bus;
210 	struct tasklet_struct bus_reset_tasklet;
211 
212 	u32 self_id_buffer[512];
213 };
214 
215 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
216 {
217 	return container_of(card, struct fw_ohci, card);
218 }
219 
220 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
221 #define IR_CONTEXT_BUFFER_FILL		0x80000000
222 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
223 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
224 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
225 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
226 
227 #define CONTEXT_RUN	0x8000
228 #define CONTEXT_WAKE	0x1000
229 #define CONTEXT_DEAD	0x0800
230 #define CONTEXT_ACTIVE	0x0400
231 
232 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
233 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
234 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
235 
236 #define OHCI1394_REGISTER_SIZE		0x800
237 #define OHCI_LOOP_COUNT			500
238 #define OHCI1394_PCI_HCI_Control	0x40
239 #define SELF_ID_BUF_SIZE		0x800
240 #define OHCI_TCODE_PHY_PACKET		0x0e
241 #define OHCI_VERSION_1_1		0x010010
242 
243 static char ohci_driver_name[] = KBUILD_MODNAME;
244 
245 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
246 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
247 
248 #define QUIRK_CYCLE_TIMER		1
249 #define QUIRK_RESET_PACKET		2
250 #define QUIRK_BE_HEADERS		4
251 #define QUIRK_NO_1394A			8
252 #define QUIRK_NO_MSI			16
253 
254 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
255 static const struct {
256 	unsigned short vendor, device, flags;
257 } ohci_quirks[] = {
258 	{PCI_VENDOR_ID_TI,	PCI_DEVICE_ID_TI_TSB12LV22, QUIRK_CYCLE_TIMER |
259 							    QUIRK_RESET_PACKET |
260 							    QUIRK_NO_1394A},
261 	{PCI_VENDOR_ID_TI,	PCI_ANY_ID,	QUIRK_RESET_PACKET},
262 	{PCI_VENDOR_ID_AL,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
263 	{PCI_VENDOR_ID_JMICRON,	PCI_DEVICE_ID_JMICRON_JMB38X_FW, QUIRK_NO_MSI},
264 	{PCI_VENDOR_ID_NEC,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
265 	{PCI_VENDOR_ID_VIA,	PCI_ANY_ID,	QUIRK_CYCLE_TIMER},
266 	{PCI_VENDOR_ID_APPLE,	PCI_DEVICE_ID_APPLE_UNI_N_FW, QUIRK_BE_HEADERS},
267 };
268 
269 /* This overrides anything that was found in ohci_quirks[]. */
270 static int param_quirks;
271 module_param_named(quirks, param_quirks, int, 0644);
272 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
273 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
274 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
275 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
276 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
277 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
278 	")");
279 
280 #define OHCI_PARAM_DEBUG_AT_AR		1
281 #define OHCI_PARAM_DEBUG_SELFIDS	2
282 #define OHCI_PARAM_DEBUG_IRQS		4
283 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
284 
285 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
286 
287 static int param_debug;
288 module_param_named(debug, param_debug, int, 0644);
289 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
290 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
291 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
292 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
293 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
294 	", or a combination, or all = -1)");
295 
296 static void log_irqs(u32 evt)
297 {
298 	if (likely(!(param_debug &
299 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
300 		return;
301 
302 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
303 	    !(evt & OHCI1394_busReset))
304 		return;
305 
306 	fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
307 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
308 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
309 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
310 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
311 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
312 	    evt & OHCI1394_isochRx		? " IR"			: "",
313 	    evt & OHCI1394_isochTx		? " IT"			: "",
314 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
315 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
316 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
317 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
318 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
319 	    evt & OHCI1394_busReset		? " busReset"		: "",
320 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
321 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
322 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
323 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
324 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
325 		    OHCI1394_cycleInconsistent |
326 		    OHCI1394_regAccessFail | OHCI1394_busReset)
327 						? " ?"			: "");
328 }
329 
330 static const char *speed[] = {
331 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
332 };
333 static const char *power[] = {
334 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
335 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
336 };
337 static const char port[] = { '.', '-', 'p', 'c', };
338 
339 static char _p(u32 *s, int shift)
340 {
341 	return port[*s >> shift & 3];
342 }
343 
344 static void log_selfids(int node_id, int generation, int self_id_count, u32 *s)
345 {
346 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
347 		return;
348 
349 	fw_notify("%d selfIDs, generation %d, local node ID %04x\n",
350 		  self_id_count, generation, node_id);
351 
352 	for (; self_id_count--; ++s)
353 		if ((*s & 1 << 23) == 0)
354 			fw_notify("selfID 0: %08x, phy %d [%c%c%c] "
355 			    "%s gc=%d %s %s%s%s\n",
356 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
357 			    speed[*s >> 14 & 3], *s >> 16 & 63,
358 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
359 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
360 		else
361 			fw_notify("selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
362 			    *s, *s >> 24 & 63,
363 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
364 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
365 }
366 
367 static const char *evts[] = {
368 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
369 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
370 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
371 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
372 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
373 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
374 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
375 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
376 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
377 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
378 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
379 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
380 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
381 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
382 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
383 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
384 	[0x20] = "pending/cancelled",
385 };
386 static const char *tcodes[] = {
387 	[0x0] = "QW req",		[0x1] = "BW req",
388 	[0x2] = "W resp",		[0x3] = "-reserved-",
389 	[0x4] = "QR req",		[0x5] = "BR req",
390 	[0x6] = "QR resp",		[0x7] = "BR resp",
391 	[0x8] = "cycle start",		[0x9] = "Lk req",
392 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
393 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
394 	[0xe] = "link internal",	[0xf] = "-reserved-",
395 };
396 static const char *phys[] = {
397 	[0x0] = "phy config packet",	[0x1] = "link-on packet",
398 	[0x2] = "self-id packet",	[0x3] = "-reserved-",
399 };
400 
401 static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
402 {
403 	int tcode = header[0] >> 4 & 0xf;
404 	char specific[12];
405 
406 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
407 		return;
408 
409 	if (unlikely(evt >= ARRAY_SIZE(evts)))
410 			evt = 0x1f;
411 
412 	if (evt == OHCI1394_evt_bus_reset) {
413 		fw_notify("A%c evt_bus_reset, generation %d\n",
414 		    dir, (header[2] >> 16) & 0xff);
415 		return;
416 	}
417 
418 	if (header[0] == ~header[1]) {
419 		fw_notify("A%c %s, %s, %08x\n",
420 		    dir, evts[evt], phys[header[0] >> 30 & 0x3], header[0]);
421 		return;
422 	}
423 
424 	switch (tcode) {
425 	case 0x0: case 0x6: case 0x8:
426 		snprintf(specific, sizeof(specific), " = %08x",
427 			 be32_to_cpu((__force __be32)header[3]));
428 		break;
429 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
430 		snprintf(specific, sizeof(specific), " %x,%x",
431 			 header[3] >> 16, header[3] & 0xffff);
432 		break;
433 	default:
434 		specific[0] = '\0';
435 	}
436 
437 	switch (tcode) {
438 	case 0xe: case 0xa:
439 		fw_notify("A%c %s, %s\n", dir, evts[evt], tcodes[tcode]);
440 		break;
441 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
442 		fw_notify("A%c spd %x tl %02x, "
443 		    "%04x -> %04x, %s, "
444 		    "%s, %04x%08x%s\n",
445 		    dir, speed, header[0] >> 10 & 0x3f,
446 		    header[1] >> 16, header[0] >> 16, evts[evt],
447 		    tcodes[tcode], header[1] & 0xffff, header[2], specific);
448 		break;
449 	default:
450 		fw_notify("A%c spd %x tl %02x, "
451 		    "%04x -> %04x, %s, "
452 		    "%s%s\n",
453 		    dir, speed, header[0] >> 10 & 0x3f,
454 		    header[1] >> 16, header[0] >> 16, evts[evt],
455 		    tcodes[tcode], specific);
456 	}
457 }
458 
459 #else
460 
461 #define param_debug 0
462 static inline void log_irqs(u32 evt) {}
463 static inline void log_selfids(int node_id, int generation, int self_id_count, u32 *s) {}
464 static inline void log_ar_at_event(char dir, int speed, u32 *header, int evt) {}
465 
466 #endif /* CONFIG_FIREWIRE_OHCI_DEBUG */
467 
468 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
469 {
470 	writel(data, ohci->registers + offset);
471 }
472 
473 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
474 {
475 	return readl(ohci->registers + offset);
476 }
477 
478 static inline void flush_writes(const struct fw_ohci *ohci)
479 {
480 	/* Do a dummy read to flush writes. */
481 	reg_read(ohci, OHCI1394_Version);
482 }
483 
484 static int read_phy_reg(struct fw_ohci *ohci, int addr)
485 {
486 	u32 val;
487 	int i;
488 
489 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
490 	for (i = 0; i < 3 + 100; i++) {
491 		val = reg_read(ohci, OHCI1394_PhyControl);
492 		if (val & OHCI1394_PhyControl_ReadDone)
493 			return OHCI1394_PhyControl_ReadData(val);
494 
495 		/*
496 		 * Try a few times without waiting.  Sleeping is necessary
497 		 * only when the link/PHY interface is busy.
498 		 */
499 		if (i >= 3)
500 			msleep(1);
501 	}
502 	fw_error("failed to read phy reg\n");
503 
504 	return -EBUSY;
505 }
506 
507 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
508 {
509 	int i;
510 
511 	reg_write(ohci, OHCI1394_PhyControl,
512 		  OHCI1394_PhyControl_Write(addr, val));
513 	for (i = 0; i < 3 + 100; i++) {
514 		val = reg_read(ohci, OHCI1394_PhyControl);
515 		if (!(val & OHCI1394_PhyControl_WritePending))
516 			return 0;
517 
518 		if (i >= 3)
519 			msleep(1);
520 	}
521 	fw_error("failed to write phy reg\n");
522 
523 	return -EBUSY;
524 }
525 
526 static int update_phy_reg(struct fw_ohci *ohci, int addr,
527 			  int clear_bits, int set_bits)
528 {
529 	int ret = read_phy_reg(ohci, addr);
530 	if (ret < 0)
531 		return ret;
532 
533 	/*
534 	 * The interrupt status bits are cleared by writing a one bit.
535 	 * Avoid clearing them unless explicitly requested in set_bits.
536 	 */
537 	if (addr == 5)
538 		clear_bits |= PHY_INT_STATUS_BITS;
539 
540 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
541 }
542 
543 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
544 {
545 	int ret;
546 
547 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
548 	if (ret < 0)
549 		return ret;
550 
551 	return read_phy_reg(ohci, addr);
552 }
553 
554 static int ohci_read_phy_reg(struct fw_card *card, int addr)
555 {
556 	struct fw_ohci *ohci = fw_ohci(card);
557 	int ret;
558 
559 	mutex_lock(&ohci->phy_reg_mutex);
560 	ret = read_phy_reg(ohci, addr);
561 	mutex_unlock(&ohci->phy_reg_mutex);
562 
563 	return ret;
564 }
565 
566 static int ohci_update_phy_reg(struct fw_card *card, int addr,
567 			       int clear_bits, int set_bits)
568 {
569 	struct fw_ohci *ohci = fw_ohci(card);
570 	int ret;
571 
572 	mutex_lock(&ohci->phy_reg_mutex);
573 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
574 	mutex_unlock(&ohci->phy_reg_mutex);
575 
576 	return ret;
577 }
578 
579 static int ar_context_add_page(struct ar_context *ctx)
580 {
581 	struct device *dev = ctx->ohci->card.device;
582 	struct ar_buffer *ab;
583 	dma_addr_t uninitialized_var(ab_bus);
584 	size_t offset;
585 
586 	ab = dma_alloc_coherent(dev, PAGE_SIZE, &ab_bus, GFP_ATOMIC);
587 	if (ab == NULL)
588 		return -ENOMEM;
589 
590 	ab->next = NULL;
591 	memset(&ab->descriptor, 0, sizeof(ab->descriptor));
592 	ab->descriptor.control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
593 						    DESCRIPTOR_STATUS |
594 						    DESCRIPTOR_BRANCH_ALWAYS);
595 	offset = offsetof(struct ar_buffer, data);
596 	ab->descriptor.req_count      = cpu_to_le16(PAGE_SIZE - offset);
597 	ab->descriptor.data_address   = cpu_to_le32(ab_bus + offset);
598 	ab->descriptor.res_count      = cpu_to_le16(PAGE_SIZE - offset);
599 	ab->descriptor.branch_address = 0;
600 
601 	wmb(); /* finish init of new descriptors before branch_address update */
602 	ctx->last_buffer->descriptor.branch_address = cpu_to_le32(ab_bus | 1);
603 	ctx->last_buffer->next = ab;
604 	ctx->last_buffer = ab;
605 
606 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
607 	flush_writes(ctx->ohci);
608 
609 	return 0;
610 }
611 
612 static void ar_context_release(struct ar_context *ctx)
613 {
614 	struct ar_buffer *ab, *ab_next;
615 	size_t offset;
616 	dma_addr_t ab_bus;
617 
618 	for (ab = ctx->current_buffer; ab; ab = ab_next) {
619 		ab_next = ab->next;
620 		offset = offsetof(struct ar_buffer, data);
621 		ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
622 		dma_free_coherent(ctx->ohci->card.device, PAGE_SIZE,
623 				  ab, ab_bus);
624 	}
625 }
626 
627 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
628 #define cond_le32_to_cpu(v) \
629 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
630 #else
631 #define cond_le32_to_cpu(v) le32_to_cpu(v)
632 #endif
633 
634 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
635 {
636 	struct fw_ohci *ohci = ctx->ohci;
637 	struct fw_packet p;
638 	u32 status, length, tcode;
639 	int evt;
640 
641 	p.header[0] = cond_le32_to_cpu(buffer[0]);
642 	p.header[1] = cond_le32_to_cpu(buffer[1]);
643 	p.header[2] = cond_le32_to_cpu(buffer[2]);
644 
645 	tcode = (p.header[0] >> 4) & 0x0f;
646 	switch (tcode) {
647 	case TCODE_WRITE_QUADLET_REQUEST:
648 	case TCODE_READ_QUADLET_RESPONSE:
649 		p.header[3] = (__force __u32) buffer[3];
650 		p.header_length = 16;
651 		p.payload_length = 0;
652 		break;
653 
654 	case TCODE_READ_BLOCK_REQUEST :
655 		p.header[3] = cond_le32_to_cpu(buffer[3]);
656 		p.header_length = 16;
657 		p.payload_length = 0;
658 		break;
659 
660 	case TCODE_WRITE_BLOCK_REQUEST:
661 	case TCODE_READ_BLOCK_RESPONSE:
662 	case TCODE_LOCK_REQUEST:
663 	case TCODE_LOCK_RESPONSE:
664 		p.header[3] = cond_le32_to_cpu(buffer[3]);
665 		p.header_length = 16;
666 		p.payload_length = p.header[3] >> 16;
667 		break;
668 
669 	case TCODE_WRITE_RESPONSE:
670 	case TCODE_READ_QUADLET_REQUEST:
671 	case OHCI_TCODE_PHY_PACKET:
672 		p.header_length = 12;
673 		p.payload_length = 0;
674 		break;
675 
676 	default:
677 		/* FIXME: Stop context, discard everything, and restart? */
678 		p.header_length = 0;
679 		p.payload_length = 0;
680 	}
681 
682 	p.payload = (void *) buffer + p.header_length;
683 
684 	/* FIXME: What to do about evt_* errors? */
685 	length = (p.header_length + p.payload_length + 3) / 4;
686 	status = cond_le32_to_cpu(buffer[length]);
687 	evt    = (status >> 16) & 0x1f;
688 
689 	p.ack        = evt - 16;
690 	p.speed      = (status >> 21) & 0x7;
691 	p.timestamp  = status & 0xffff;
692 	p.generation = ohci->request_generation;
693 
694 	log_ar_at_event('R', p.speed, p.header, evt);
695 
696 	/*
697 	 * The OHCI bus reset handler synthesizes a phy packet with
698 	 * the new generation number when a bus reset happens (see
699 	 * section 8.4.2.3).  This helps us determine when a request
700 	 * was received and make sure we send the response in the same
701 	 * generation.  We only need this for requests; for responses
702 	 * we use the unique tlabel for finding the matching
703 	 * request.
704 	 *
705 	 * Alas some chips sometimes emit bus reset packets with a
706 	 * wrong generation.  We set the correct generation for these
707 	 * at a slightly incorrect time (in bus_reset_tasklet).
708 	 */
709 	if (evt == OHCI1394_evt_bus_reset) {
710 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
711 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
712 	} else if (ctx == &ohci->ar_request_ctx) {
713 		fw_core_handle_request(&ohci->card, &p);
714 	} else {
715 		fw_core_handle_response(&ohci->card, &p);
716 	}
717 
718 	return buffer + length + 1;
719 }
720 
721 static void ar_context_tasklet(unsigned long data)
722 {
723 	struct ar_context *ctx = (struct ar_context *)data;
724 	struct fw_ohci *ohci = ctx->ohci;
725 	struct ar_buffer *ab;
726 	struct descriptor *d;
727 	void *buffer, *end;
728 
729 	ab = ctx->current_buffer;
730 	d = &ab->descriptor;
731 
732 	if (d->res_count == 0) {
733 		size_t size, rest, offset;
734 		dma_addr_t start_bus;
735 		void *start;
736 
737 		/*
738 		 * This descriptor is finished and we may have a
739 		 * packet split across this and the next buffer. We
740 		 * reuse the page for reassembling the split packet.
741 		 */
742 
743 		offset = offsetof(struct ar_buffer, data);
744 		start = buffer = ab;
745 		start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
746 
747 		ab = ab->next;
748 		d = &ab->descriptor;
749 		size = buffer + PAGE_SIZE - ctx->pointer;
750 		rest = le16_to_cpu(d->req_count) - le16_to_cpu(d->res_count);
751 		memmove(buffer, ctx->pointer, size);
752 		memcpy(buffer + size, ab->data, rest);
753 		ctx->current_buffer = ab;
754 		ctx->pointer = (void *) ab->data + rest;
755 		end = buffer + size + rest;
756 
757 		while (buffer < end)
758 			buffer = handle_ar_packet(ctx, buffer);
759 
760 		dma_free_coherent(ohci->card.device, PAGE_SIZE,
761 				  start, start_bus);
762 		ar_context_add_page(ctx);
763 	} else {
764 		buffer = ctx->pointer;
765 		ctx->pointer = end =
766 			(void *) ab + PAGE_SIZE - le16_to_cpu(d->res_count);
767 
768 		while (buffer < end)
769 			buffer = handle_ar_packet(ctx, buffer);
770 	}
771 }
772 
773 static int ar_context_init(struct ar_context *ctx,
774 			   struct fw_ohci *ohci, u32 regs)
775 {
776 	struct ar_buffer ab;
777 
778 	ctx->regs        = regs;
779 	ctx->ohci        = ohci;
780 	ctx->last_buffer = &ab;
781 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
782 
783 	ar_context_add_page(ctx);
784 	ar_context_add_page(ctx);
785 	ctx->current_buffer = ab.next;
786 	ctx->pointer = ctx->current_buffer->data;
787 
788 	return 0;
789 }
790 
791 static void ar_context_run(struct ar_context *ctx)
792 {
793 	struct ar_buffer *ab = ctx->current_buffer;
794 	dma_addr_t ab_bus;
795 	size_t offset;
796 
797 	offset = offsetof(struct ar_buffer, data);
798 	ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
799 
800 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ab_bus | 1);
801 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
802 	flush_writes(ctx->ohci);
803 }
804 
805 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
806 {
807 	int b, key;
808 
809 	b   = (le16_to_cpu(d->control) & DESCRIPTOR_BRANCH_ALWAYS) >> 2;
810 	key = (le16_to_cpu(d->control) & DESCRIPTOR_KEY_IMMEDIATE) >> 8;
811 
812 	/* figure out which descriptor the branch address goes in */
813 	if (z == 2 && (b == 3 || key == 2))
814 		return d;
815 	else
816 		return d + z - 1;
817 }
818 
819 static void context_tasklet(unsigned long data)
820 {
821 	struct context *ctx = (struct context *) data;
822 	struct descriptor *d, *last;
823 	u32 address;
824 	int z;
825 	struct descriptor_buffer *desc;
826 
827 	desc = list_entry(ctx->buffer_list.next,
828 			struct descriptor_buffer, list);
829 	last = ctx->last;
830 	while (last->branch_address != 0) {
831 		struct descriptor_buffer *old_desc = desc;
832 		address = le32_to_cpu(last->branch_address);
833 		z = address & 0xf;
834 		address &= ~0xf;
835 
836 		/* If the branch address points to a buffer outside of the
837 		 * current buffer, advance to the next buffer. */
838 		if (address < desc->buffer_bus ||
839 				address >= desc->buffer_bus + desc->used)
840 			desc = list_entry(desc->list.next,
841 					struct descriptor_buffer, list);
842 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
843 		last = find_branch_descriptor(d, z);
844 
845 		if (!ctx->callback(ctx, d, last))
846 			break;
847 
848 		if (old_desc != desc) {
849 			/* If we've advanced to the next buffer, move the
850 			 * previous buffer to the free list. */
851 			unsigned long flags;
852 			old_desc->used = 0;
853 			spin_lock_irqsave(&ctx->ohci->lock, flags);
854 			list_move_tail(&old_desc->list, &ctx->buffer_list);
855 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
856 		}
857 		ctx->last = last;
858 	}
859 }
860 
861 /*
862  * Allocate a new buffer and add it to the list of free buffers for this
863  * context.  Must be called with ohci->lock held.
864  */
865 static int context_add_buffer(struct context *ctx)
866 {
867 	struct descriptor_buffer *desc;
868 	dma_addr_t uninitialized_var(bus_addr);
869 	int offset;
870 
871 	/*
872 	 * 16MB of descriptors should be far more than enough for any DMA
873 	 * program.  This will catch run-away userspace or DoS attacks.
874 	 */
875 	if (ctx->total_allocation >= 16*1024*1024)
876 		return -ENOMEM;
877 
878 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
879 			&bus_addr, GFP_ATOMIC);
880 	if (!desc)
881 		return -ENOMEM;
882 
883 	offset = (void *)&desc->buffer - (void *)desc;
884 	desc->buffer_size = PAGE_SIZE - offset;
885 	desc->buffer_bus = bus_addr + offset;
886 	desc->used = 0;
887 
888 	list_add_tail(&desc->list, &ctx->buffer_list);
889 	ctx->total_allocation += PAGE_SIZE;
890 
891 	return 0;
892 }
893 
894 static int context_init(struct context *ctx, struct fw_ohci *ohci,
895 			u32 regs, descriptor_callback_t callback)
896 {
897 	ctx->ohci = ohci;
898 	ctx->regs = regs;
899 	ctx->total_allocation = 0;
900 
901 	INIT_LIST_HEAD(&ctx->buffer_list);
902 	if (context_add_buffer(ctx) < 0)
903 		return -ENOMEM;
904 
905 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
906 			struct descriptor_buffer, list);
907 
908 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
909 	ctx->callback = callback;
910 
911 	/*
912 	 * We put a dummy descriptor in the buffer that has a NULL
913 	 * branch address and looks like it's been sent.  That way we
914 	 * have a descriptor to append DMA programs to.
915 	 */
916 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
917 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
918 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
919 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
920 	ctx->last = ctx->buffer_tail->buffer;
921 	ctx->prev = ctx->buffer_tail->buffer;
922 
923 	return 0;
924 }
925 
926 static void context_release(struct context *ctx)
927 {
928 	struct fw_card *card = &ctx->ohci->card;
929 	struct descriptor_buffer *desc, *tmp;
930 
931 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
932 		dma_free_coherent(card->device, PAGE_SIZE, desc,
933 			desc->buffer_bus -
934 			((void *)&desc->buffer - (void *)desc));
935 }
936 
937 /* Must be called with ohci->lock held */
938 static struct descriptor *context_get_descriptors(struct context *ctx,
939 						  int z, dma_addr_t *d_bus)
940 {
941 	struct descriptor *d = NULL;
942 	struct descriptor_buffer *desc = ctx->buffer_tail;
943 
944 	if (z * sizeof(*d) > desc->buffer_size)
945 		return NULL;
946 
947 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
948 		/* No room for the descriptor in this buffer, so advance to the
949 		 * next one. */
950 
951 		if (desc->list.next == &ctx->buffer_list) {
952 			/* If there is no free buffer next in the list,
953 			 * allocate one. */
954 			if (context_add_buffer(ctx) < 0)
955 				return NULL;
956 		}
957 		desc = list_entry(desc->list.next,
958 				struct descriptor_buffer, list);
959 		ctx->buffer_tail = desc;
960 	}
961 
962 	d = desc->buffer + desc->used / sizeof(*d);
963 	memset(d, 0, z * sizeof(*d));
964 	*d_bus = desc->buffer_bus + desc->used;
965 
966 	return d;
967 }
968 
969 static void context_run(struct context *ctx, u32 extra)
970 {
971 	struct fw_ohci *ohci = ctx->ohci;
972 
973 	reg_write(ohci, COMMAND_PTR(ctx->regs),
974 		  le32_to_cpu(ctx->last->branch_address));
975 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
976 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
977 	flush_writes(ohci);
978 }
979 
980 static void context_append(struct context *ctx,
981 			   struct descriptor *d, int z, int extra)
982 {
983 	dma_addr_t d_bus;
984 	struct descriptor_buffer *desc = ctx->buffer_tail;
985 
986 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
987 
988 	desc->used += (z + extra) * sizeof(*d);
989 
990 	wmb(); /* finish init of new descriptors before branch_address update */
991 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
992 	ctx->prev = find_branch_descriptor(d, z);
993 
994 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
995 	flush_writes(ctx->ohci);
996 }
997 
998 static void context_stop(struct context *ctx)
999 {
1000 	u32 reg;
1001 	int i;
1002 
1003 	reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1004 	flush_writes(ctx->ohci);
1005 
1006 	for (i = 0; i < 10; i++) {
1007 		reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1008 		if ((reg & CONTEXT_ACTIVE) == 0)
1009 			return;
1010 
1011 		mdelay(1);
1012 	}
1013 	fw_error("Error: DMA context still active (0x%08x)\n", reg);
1014 }
1015 
1016 struct driver_data {
1017 	struct fw_packet *packet;
1018 };
1019 
1020 /*
1021  * This function apppends a packet to the DMA queue for transmission.
1022  * Must always be called with the ochi->lock held to ensure proper
1023  * generation handling and locking around packet queue manipulation.
1024  */
1025 static int at_context_queue_packet(struct context *ctx,
1026 				   struct fw_packet *packet)
1027 {
1028 	struct fw_ohci *ohci = ctx->ohci;
1029 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1030 	struct driver_data *driver_data;
1031 	struct descriptor *d, *last;
1032 	__le32 *header;
1033 	int z, tcode;
1034 	u32 reg;
1035 
1036 	d = context_get_descriptors(ctx, 4, &d_bus);
1037 	if (d == NULL) {
1038 		packet->ack = RCODE_SEND_ERROR;
1039 		return -1;
1040 	}
1041 
1042 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1043 	d[0].res_count = cpu_to_le16(packet->timestamp);
1044 
1045 	/*
1046 	 * The DMA format for asyncronous link packets is different
1047 	 * from the IEEE1394 layout, so shift the fields around
1048 	 * accordingly.  If header_length is 8, it's a PHY packet, to
1049 	 * which we need to prepend an extra quadlet.
1050 	 */
1051 
1052 	header = (__le32 *) &d[1];
1053 	switch (packet->header_length) {
1054 	case 16:
1055 	case 12:
1056 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1057 					(packet->speed << 16));
1058 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1059 					(packet->header[0] & 0xffff0000));
1060 		header[2] = cpu_to_le32(packet->header[2]);
1061 
1062 		tcode = (packet->header[0] >> 4) & 0x0f;
1063 		if (TCODE_IS_BLOCK_PACKET(tcode))
1064 			header[3] = cpu_to_le32(packet->header[3]);
1065 		else
1066 			header[3] = (__force __le32) packet->header[3];
1067 
1068 		d[0].req_count = cpu_to_le16(packet->header_length);
1069 		break;
1070 
1071 	case 8:
1072 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1073 					(packet->speed << 16));
1074 		header[1] = cpu_to_le32(packet->header[0]);
1075 		header[2] = cpu_to_le32(packet->header[1]);
1076 		d[0].req_count = cpu_to_le16(12);
1077 
1078 		if (is_ping_packet(packet->header))
1079 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1080 		break;
1081 
1082 	case 4:
1083 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1084 					(packet->speed << 16));
1085 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1086 		d[0].req_count = cpu_to_le16(8);
1087 		break;
1088 
1089 	default:
1090 		/* BUG(); */
1091 		packet->ack = RCODE_SEND_ERROR;
1092 		return -1;
1093 	}
1094 
1095 	driver_data = (struct driver_data *) &d[3];
1096 	driver_data->packet = packet;
1097 	packet->driver_data = driver_data;
1098 
1099 	if (packet->payload_length > 0) {
1100 		payload_bus =
1101 			dma_map_single(ohci->card.device, packet->payload,
1102 				       packet->payload_length, DMA_TO_DEVICE);
1103 		if (dma_mapping_error(ohci->card.device, payload_bus)) {
1104 			packet->ack = RCODE_SEND_ERROR;
1105 			return -1;
1106 		}
1107 		packet->payload_bus	= payload_bus;
1108 		packet->payload_mapped	= true;
1109 
1110 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1111 		d[2].data_address = cpu_to_le32(payload_bus);
1112 		last = &d[2];
1113 		z = 3;
1114 	} else {
1115 		last = &d[0];
1116 		z = 2;
1117 	}
1118 
1119 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1120 				     DESCRIPTOR_IRQ_ALWAYS |
1121 				     DESCRIPTOR_BRANCH_ALWAYS);
1122 
1123 	/*
1124 	 * If the controller and packet generations don't match, we need to
1125 	 * bail out and try again.  If IntEvent.busReset is set, the AT context
1126 	 * is halted, so appending to the context and trying to run it is
1127 	 * futile.  Most controllers do the right thing and just flush the AT
1128 	 * queue (per section 7.2.3.2 of the OHCI 1.1 specification), but
1129 	 * some controllers (like a JMicron JMB381 PCI-e) misbehave and wind
1130 	 * up stalling out.  So we just bail out in software and try again
1131 	 * later, and everyone is happy.
1132 	 * FIXME: Document how the locking works.
1133 	 */
1134 	if (ohci->generation != packet->generation ||
1135 	    reg_read(ohci, OHCI1394_IntEventSet) & OHCI1394_busReset) {
1136 		if (packet->payload_mapped)
1137 			dma_unmap_single(ohci->card.device, payload_bus,
1138 					 packet->payload_length, DMA_TO_DEVICE);
1139 		packet->ack = RCODE_GENERATION;
1140 		return -1;
1141 	}
1142 
1143 	context_append(ctx, d, z, 4 - z);
1144 
1145 	/* If the context isn't already running, start it up. */
1146 	reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1147 	if ((reg & CONTEXT_RUN) == 0)
1148 		context_run(ctx, 0);
1149 
1150 	return 0;
1151 }
1152 
1153 static int handle_at_packet(struct context *context,
1154 			    struct descriptor *d,
1155 			    struct descriptor *last)
1156 {
1157 	struct driver_data *driver_data;
1158 	struct fw_packet *packet;
1159 	struct fw_ohci *ohci = context->ohci;
1160 	int evt;
1161 
1162 	if (last->transfer_status == 0)
1163 		/* This descriptor isn't done yet, stop iteration. */
1164 		return 0;
1165 
1166 	driver_data = (struct driver_data *) &d[3];
1167 	packet = driver_data->packet;
1168 	if (packet == NULL)
1169 		/* This packet was cancelled, just continue. */
1170 		return 1;
1171 
1172 	if (packet->payload_mapped)
1173 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1174 				 packet->payload_length, DMA_TO_DEVICE);
1175 
1176 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1177 	packet->timestamp = le16_to_cpu(last->res_count);
1178 
1179 	log_ar_at_event('T', packet->speed, packet->header, evt);
1180 
1181 	switch (evt) {
1182 	case OHCI1394_evt_timeout:
1183 		/* Async response transmit timed out. */
1184 		packet->ack = RCODE_CANCELLED;
1185 		break;
1186 
1187 	case OHCI1394_evt_flushed:
1188 		/*
1189 		 * The packet was flushed should give same error as
1190 		 * when we try to use a stale generation count.
1191 		 */
1192 		packet->ack = RCODE_GENERATION;
1193 		break;
1194 
1195 	case OHCI1394_evt_missing_ack:
1196 		/*
1197 		 * Using a valid (current) generation count, but the
1198 		 * node is not on the bus or not sending acks.
1199 		 */
1200 		packet->ack = RCODE_NO_ACK;
1201 		break;
1202 
1203 	case ACK_COMPLETE + 0x10:
1204 	case ACK_PENDING + 0x10:
1205 	case ACK_BUSY_X + 0x10:
1206 	case ACK_BUSY_A + 0x10:
1207 	case ACK_BUSY_B + 0x10:
1208 	case ACK_DATA_ERROR + 0x10:
1209 	case ACK_TYPE_ERROR + 0x10:
1210 		packet->ack = evt - 0x10;
1211 		break;
1212 
1213 	default:
1214 		packet->ack = RCODE_SEND_ERROR;
1215 		break;
1216 	}
1217 
1218 	packet->callback(packet, &ohci->card, packet->ack);
1219 
1220 	return 1;
1221 }
1222 
1223 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1224 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1225 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1226 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1227 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1228 
1229 static void handle_local_rom(struct fw_ohci *ohci,
1230 			     struct fw_packet *packet, u32 csr)
1231 {
1232 	struct fw_packet response;
1233 	int tcode, length, i;
1234 
1235 	tcode = HEADER_GET_TCODE(packet->header[0]);
1236 	if (TCODE_IS_BLOCK_PACKET(tcode))
1237 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1238 	else
1239 		length = 4;
1240 
1241 	i = csr - CSR_CONFIG_ROM;
1242 	if (i + length > CONFIG_ROM_SIZE) {
1243 		fw_fill_response(&response, packet->header,
1244 				 RCODE_ADDRESS_ERROR, NULL, 0);
1245 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1246 		fw_fill_response(&response, packet->header,
1247 				 RCODE_TYPE_ERROR, NULL, 0);
1248 	} else {
1249 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1250 				 (void *) ohci->config_rom + i, length);
1251 	}
1252 
1253 	fw_core_handle_response(&ohci->card, &response);
1254 }
1255 
1256 static void handle_local_lock(struct fw_ohci *ohci,
1257 			      struct fw_packet *packet, u32 csr)
1258 {
1259 	struct fw_packet response;
1260 	int tcode, length, ext_tcode, sel, try;
1261 	__be32 *payload, lock_old;
1262 	u32 lock_arg, lock_data;
1263 
1264 	tcode = HEADER_GET_TCODE(packet->header[0]);
1265 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1266 	payload = packet->payload;
1267 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1268 
1269 	if (tcode == TCODE_LOCK_REQUEST &&
1270 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1271 		lock_arg = be32_to_cpu(payload[0]);
1272 		lock_data = be32_to_cpu(payload[1]);
1273 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1274 		lock_arg = 0;
1275 		lock_data = 0;
1276 	} else {
1277 		fw_fill_response(&response, packet->header,
1278 				 RCODE_TYPE_ERROR, NULL, 0);
1279 		goto out;
1280 	}
1281 
1282 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1283 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1284 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1285 	reg_write(ohci, OHCI1394_CSRControl, sel);
1286 
1287 	for (try = 0; try < 20; try++)
1288 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1289 			lock_old = cpu_to_be32(reg_read(ohci,
1290 							OHCI1394_CSRData));
1291 			fw_fill_response(&response, packet->header,
1292 					 RCODE_COMPLETE,
1293 					 &lock_old, sizeof(lock_old));
1294 			goto out;
1295 		}
1296 
1297 	fw_error("swap not done (CSR lock timeout)\n");
1298 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1299 
1300  out:
1301 	fw_core_handle_response(&ohci->card, &response);
1302 }
1303 
1304 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1305 {
1306 	u64 offset, csr;
1307 
1308 	if (ctx == &ctx->ohci->at_request_ctx) {
1309 		packet->ack = ACK_PENDING;
1310 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1311 	}
1312 
1313 	offset =
1314 		((unsigned long long)
1315 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1316 		packet->header[2];
1317 	csr = offset - CSR_REGISTER_BASE;
1318 
1319 	/* Handle config rom reads. */
1320 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1321 		handle_local_rom(ctx->ohci, packet, csr);
1322 	else switch (csr) {
1323 	case CSR_BUS_MANAGER_ID:
1324 	case CSR_BANDWIDTH_AVAILABLE:
1325 	case CSR_CHANNELS_AVAILABLE_HI:
1326 	case CSR_CHANNELS_AVAILABLE_LO:
1327 		handle_local_lock(ctx->ohci, packet, csr);
1328 		break;
1329 	default:
1330 		if (ctx == &ctx->ohci->at_request_ctx)
1331 			fw_core_handle_request(&ctx->ohci->card, packet);
1332 		else
1333 			fw_core_handle_response(&ctx->ohci->card, packet);
1334 		break;
1335 	}
1336 
1337 	if (ctx == &ctx->ohci->at_response_ctx) {
1338 		packet->ack = ACK_COMPLETE;
1339 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1340 	}
1341 }
1342 
1343 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1344 {
1345 	unsigned long flags;
1346 	int ret;
1347 
1348 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1349 
1350 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1351 	    ctx->ohci->generation == packet->generation) {
1352 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1353 		handle_local_request(ctx, packet);
1354 		return;
1355 	}
1356 
1357 	ret = at_context_queue_packet(ctx, packet);
1358 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1359 
1360 	if (ret < 0)
1361 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1362 
1363 }
1364 
1365 static u32 cycle_timer_ticks(u32 cycle_timer)
1366 {
1367 	u32 ticks;
1368 
1369 	ticks = cycle_timer & 0xfff;
1370 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1371 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1372 
1373 	return ticks;
1374 }
1375 
1376 /*
1377  * Some controllers exhibit one or more of the following bugs when updating the
1378  * iso cycle timer register:
1379  *  - When the lowest six bits are wrapping around to zero, a read that happens
1380  *    at the same time will return garbage in the lowest ten bits.
1381  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1382  *    not incremented for about 60 ns.
1383  *  - Occasionally, the entire register reads zero.
1384  *
1385  * To catch these, we read the register three times and ensure that the
1386  * difference between each two consecutive reads is approximately the same, i.e.
1387  * less than twice the other.  Furthermore, any negative difference indicates an
1388  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1389  * execute, so we have enough precision to compute the ratio of the differences.)
1390  */
1391 static u32 get_cycle_time(struct fw_ohci *ohci)
1392 {
1393 	u32 c0, c1, c2;
1394 	u32 t0, t1, t2;
1395 	s32 diff01, diff12;
1396 	int i;
1397 
1398 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1399 
1400 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1401 		i = 0;
1402 		c1 = c2;
1403 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1404 		do {
1405 			c0 = c1;
1406 			c1 = c2;
1407 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1408 			t0 = cycle_timer_ticks(c0);
1409 			t1 = cycle_timer_ticks(c1);
1410 			t2 = cycle_timer_ticks(c2);
1411 			diff01 = t1 - t0;
1412 			diff12 = t2 - t1;
1413 		} while ((diff01 <= 0 || diff12 <= 0 ||
1414 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1415 			 && i++ < 20);
1416 	}
1417 
1418 	return c2;
1419 }
1420 
1421 /*
1422  * This function has to be called at least every 64 seconds.  The bus_time
1423  * field stores not only the upper 25 bits of the BUS_TIME register but also
1424  * the most significant bit of the cycle timer in bit 6 so that we can detect
1425  * changes in this bit.
1426  */
1427 static u32 update_bus_time(struct fw_ohci *ohci)
1428 {
1429 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1430 
1431 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1432 		ohci->bus_time += 0x40;
1433 
1434 	return ohci->bus_time | cycle_time_seconds;
1435 }
1436 
1437 static void bus_reset_tasklet(unsigned long data)
1438 {
1439 	struct fw_ohci *ohci = (struct fw_ohci *)data;
1440 	int self_id_count, i, j, reg;
1441 	int generation, new_generation;
1442 	unsigned long flags;
1443 	void *free_rom = NULL;
1444 	dma_addr_t free_rom_bus = 0;
1445 	bool is_new_root;
1446 
1447 	reg = reg_read(ohci, OHCI1394_NodeID);
1448 	if (!(reg & OHCI1394_NodeID_idValid)) {
1449 		fw_notify("node ID not valid, new bus reset in progress\n");
1450 		return;
1451 	}
1452 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1453 		fw_notify("malconfigured bus\n");
1454 		return;
1455 	}
1456 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1457 			       OHCI1394_NodeID_nodeNumber);
1458 
1459 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1460 	if (!(ohci->is_root && is_new_root))
1461 		reg_write(ohci, OHCI1394_LinkControlSet,
1462 			  OHCI1394_LinkControl_cycleMaster);
1463 	ohci->is_root = is_new_root;
1464 
1465 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1466 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1467 		fw_notify("inconsistent self IDs\n");
1468 		return;
1469 	}
1470 	/*
1471 	 * The count in the SelfIDCount register is the number of
1472 	 * bytes in the self ID receive buffer.  Since we also receive
1473 	 * the inverted quadlets and a header quadlet, we shift one
1474 	 * bit extra to get the actual number of self IDs.
1475 	 */
1476 	self_id_count = (reg >> 3) & 0xff;
1477 	if (self_id_count == 0 || self_id_count > 252) {
1478 		fw_notify("inconsistent self IDs\n");
1479 		return;
1480 	}
1481 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1482 	rmb();
1483 
1484 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1485 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1486 			fw_notify("inconsistent self IDs\n");
1487 			return;
1488 		}
1489 		ohci->self_id_buffer[j] =
1490 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1491 	}
1492 	rmb();
1493 
1494 	/*
1495 	 * Check the consistency of the self IDs we just read.  The
1496 	 * problem we face is that a new bus reset can start while we
1497 	 * read out the self IDs from the DMA buffer. If this happens,
1498 	 * the DMA buffer will be overwritten with new self IDs and we
1499 	 * will read out inconsistent data.  The OHCI specification
1500 	 * (section 11.2) recommends a technique similar to
1501 	 * linux/seqlock.h, where we remember the generation of the
1502 	 * self IDs in the buffer before reading them out and compare
1503 	 * it to the current generation after reading them out.  If
1504 	 * the two generations match we know we have a consistent set
1505 	 * of self IDs.
1506 	 */
1507 
1508 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1509 	if (new_generation != generation) {
1510 		fw_notify("recursive bus reset detected, "
1511 			  "discarding self ids\n");
1512 		return;
1513 	}
1514 
1515 	/* FIXME: Document how the locking works. */
1516 	spin_lock_irqsave(&ohci->lock, flags);
1517 
1518 	ohci->generation = generation;
1519 	context_stop(&ohci->at_request_ctx);
1520 	context_stop(&ohci->at_response_ctx);
1521 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1522 
1523 	if (ohci->quirks & QUIRK_RESET_PACKET)
1524 		ohci->request_generation = generation;
1525 
1526 	/*
1527 	 * This next bit is unrelated to the AT context stuff but we
1528 	 * have to do it under the spinlock also.  If a new config rom
1529 	 * was set up before this reset, the old one is now no longer
1530 	 * in use and we can free it. Update the config rom pointers
1531 	 * to point to the current config rom and clear the
1532 	 * next_config_rom pointer so a new update can take place.
1533 	 */
1534 
1535 	if (ohci->next_config_rom != NULL) {
1536 		if (ohci->next_config_rom != ohci->config_rom) {
1537 			free_rom      = ohci->config_rom;
1538 			free_rom_bus  = ohci->config_rom_bus;
1539 		}
1540 		ohci->config_rom      = ohci->next_config_rom;
1541 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1542 		ohci->next_config_rom = NULL;
1543 
1544 		/*
1545 		 * Restore config_rom image and manually update
1546 		 * config_rom registers.  Writing the header quadlet
1547 		 * will indicate that the config rom is ready, so we
1548 		 * do that last.
1549 		 */
1550 		reg_write(ohci, OHCI1394_BusOptions,
1551 			  be32_to_cpu(ohci->config_rom[2]));
1552 		ohci->config_rom[0] = ohci->next_header;
1553 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1554 			  be32_to_cpu(ohci->next_header));
1555 	}
1556 
1557 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1558 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1559 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1560 #endif
1561 
1562 	spin_unlock_irqrestore(&ohci->lock, flags);
1563 
1564 	if (free_rom)
1565 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1566 				  free_rom, free_rom_bus);
1567 
1568 	log_selfids(ohci->node_id, generation,
1569 		    self_id_count, ohci->self_id_buffer);
1570 
1571 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1572 				 self_id_count, ohci->self_id_buffer,
1573 				 ohci->csr_state_setclear_abdicate);
1574 	ohci->csr_state_setclear_abdicate = false;
1575 }
1576 
1577 static irqreturn_t irq_handler(int irq, void *data)
1578 {
1579 	struct fw_ohci *ohci = data;
1580 	u32 event, iso_event;
1581 	int i;
1582 
1583 	event = reg_read(ohci, OHCI1394_IntEventClear);
1584 
1585 	if (!event || !~event)
1586 		return IRQ_NONE;
1587 
1588 	/* busReset must not be cleared yet, see OHCI 1.1 clause 7.2.3.2 */
1589 	reg_write(ohci, OHCI1394_IntEventClear, event & ~OHCI1394_busReset);
1590 	log_irqs(event);
1591 
1592 	if (event & OHCI1394_selfIDComplete)
1593 		tasklet_schedule(&ohci->bus_reset_tasklet);
1594 
1595 	if (event & OHCI1394_RQPkt)
1596 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1597 
1598 	if (event & OHCI1394_RSPkt)
1599 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1600 
1601 	if (event & OHCI1394_reqTxComplete)
1602 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
1603 
1604 	if (event & OHCI1394_respTxComplete)
1605 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
1606 
1607 	iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1608 	reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1609 
1610 	while (iso_event) {
1611 		i = ffs(iso_event) - 1;
1612 		tasklet_schedule(&ohci->ir_context_list[i].context.tasklet);
1613 		iso_event &= ~(1 << i);
1614 	}
1615 
1616 	iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1617 	reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1618 
1619 	while (iso_event) {
1620 		i = ffs(iso_event) - 1;
1621 		tasklet_schedule(&ohci->it_context_list[i].context.tasklet);
1622 		iso_event &= ~(1 << i);
1623 	}
1624 
1625 	if (unlikely(event & OHCI1394_regAccessFail))
1626 		fw_error("Register access failure - "
1627 			 "please notify linux1394-devel@lists.sf.net\n");
1628 
1629 	if (unlikely(event & OHCI1394_postedWriteErr))
1630 		fw_error("PCI posted write error\n");
1631 
1632 	if (unlikely(event & OHCI1394_cycleTooLong)) {
1633 		if (printk_ratelimit())
1634 			fw_notify("isochronous cycle too long\n");
1635 		reg_write(ohci, OHCI1394_LinkControlSet,
1636 			  OHCI1394_LinkControl_cycleMaster);
1637 	}
1638 
1639 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
1640 		/*
1641 		 * We need to clear this event bit in order to make
1642 		 * cycleMatch isochronous I/O work.  In theory we should
1643 		 * stop active cycleMatch iso contexts now and restart
1644 		 * them at least two cycles later.  (FIXME?)
1645 		 */
1646 		if (printk_ratelimit())
1647 			fw_notify("isochronous cycle inconsistent\n");
1648 	}
1649 
1650 	if (event & OHCI1394_cycle64Seconds) {
1651 		spin_lock(&ohci->lock);
1652 		update_bus_time(ohci);
1653 		spin_unlock(&ohci->lock);
1654 	}
1655 
1656 	return IRQ_HANDLED;
1657 }
1658 
1659 static int software_reset(struct fw_ohci *ohci)
1660 {
1661 	int i;
1662 
1663 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1664 
1665 	for (i = 0; i < OHCI_LOOP_COUNT; i++) {
1666 		if ((reg_read(ohci, OHCI1394_HCControlSet) &
1667 		     OHCI1394_HCControl_softReset) == 0)
1668 			return 0;
1669 		msleep(1);
1670 	}
1671 
1672 	return -EBUSY;
1673 }
1674 
1675 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
1676 {
1677 	size_t size = length * 4;
1678 
1679 	memcpy(dest, src, size);
1680 	if (size < CONFIG_ROM_SIZE)
1681 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
1682 }
1683 
1684 static int configure_1394a_enhancements(struct fw_ohci *ohci)
1685 {
1686 	bool enable_1394a;
1687 	int ret, clear, set, offset;
1688 
1689 	/* Check if the driver should configure link and PHY. */
1690 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
1691 	      OHCI1394_HCControl_programPhyEnable))
1692 		return 0;
1693 
1694 	/* Paranoia: check whether the PHY supports 1394a, too. */
1695 	enable_1394a = false;
1696 	ret = read_phy_reg(ohci, 2);
1697 	if (ret < 0)
1698 		return ret;
1699 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
1700 		ret = read_paged_phy_reg(ohci, 1, 8);
1701 		if (ret < 0)
1702 			return ret;
1703 		if (ret >= 1)
1704 			enable_1394a = true;
1705 	}
1706 
1707 	if (ohci->quirks & QUIRK_NO_1394A)
1708 		enable_1394a = false;
1709 
1710 	/* Configure PHY and link consistently. */
1711 	if (enable_1394a) {
1712 		clear = 0;
1713 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
1714 	} else {
1715 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
1716 		set = 0;
1717 	}
1718 	ret = update_phy_reg(ohci, 5, clear, set);
1719 	if (ret < 0)
1720 		return ret;
1721 
1722 	if (enable_1394a)
1723 		offset = OHCI1394_HCControlSet;
1724 	else
1725 		offset = OHCI1394_HCControlClear;
1726 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
1727 
1728 	/* Clean up: configuration has been taken care of. */
1729 	reg_write(ohci, OHCI1394_HCControlClear,
1730 		  OHCI1394_HCControl_programPhyEnable);
1731 
1732 	return 0;
1733 }
1734 
1735 static int ohci_enable(struct fw_card *card,
1736 		       const __be32 *config_rom, size_t length)
1737 {
1738 	struct fw_ohci *ohci = fw_ohci(card);
1739 	struct pci_dev *dev = to_pci_dev(card->device);
1740 	u32 lps, seconds, version, irqs;
1741 	int i, ret;
1742 
1743 	if (software_reset(ohci)) {
1744 		fw_error("Failed to reset ohci card.\n");
1745 		return -EBUSY;
1746 	}
1747 
1748 	/*
1749 	 * Now enable LPS, which we need in order to start accessing
1750 	 * most of the registers.  In fact, on some cards (ALI M5251),
1751 	 * accessing registers in the SClk domain without LPS enabled
1752 	 * will lock up the machine.  Wait 50msec to make sure we have
1753 	 * full link enabled.  However, with some cards (well, at least
1754 	 * a JMicron PCIe card), we have to try again sometimes.
1755 	 */
1756 	reg_write(ohci, OHCI1394_HCControlSet,
1757 		  OHCI1394_HCControl_LPS |
1758 		  OHCI1394_HCControl_postedWriteEnable);
1759 	flush_writes(ohci);
1760 
1761 	for (lps = 0, i = 0; !lps && i < 3; i++) {
1762 		msleep(50);
1763 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
1764 		      OHCI1394_HCControl_LPS;
1765 	}
1766 
1767 	if (!lps) {
1768 		fw_error("Failed to set Link Power Status\n");
1769 		return -EIO;
1770 	}
1771 
1772 	reg_write(ohci, OHCI1394_HCControlClear,
1773 		  OHCI1394_HCControl_noByteSwapData);
1774 
1775 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
1776 	reg_write(ohci, OHCI1394_LinkControlSet,
1777 		  OHCI1394_LinkControl_rcvSelfID |
1778 		  OHCI1394_LinkControl_rcvPhyPkt |
1779 		  OHCI1394_LinkControl_cycleTimerEnable |
1780 		  OHCI1394_LinkControl_cycleMaster);
1781 
1782 	reg_write(ohci, OHCI1394_ATRetries,
1783 		  OHCI1394_MAX_AT_REQ_RETRIES |
1784 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
1785 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
1786 		  (200 << 16));
1787 
1788 	seconds = lower_32_bits(get_seconds());
1789 	reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
1790 	ohci->bus_time = seconds & ~0x3f;
1791 
1792 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
1793 	if (version >= OHCI_VERSION_1_1) {
1794 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
1795 			  0xfffffffe);
1796 		card->broadcast_channel_auto_allocated = true;
1797 	}
1798 
1799 	/* Get implemented bits of the priority arbitration request counter. */
1800 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
1801 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
1802 	reg_write(ohci, OHCI1394_FairnessControl, 0);
1803 	card->priority_budget_implemented = ohci->pri_req_max != 0;
1804 
1805 	ar_context_run(&ohci->ar_request_ctx);
1806 	ar_context_run(&ohci->ar_response_ctx);
1807 
1808 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
1809 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
1810 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
1811 
1812 	ret = configure_1394a_enhancements(ohci);
1813 	if (ret < 0)
1814 		return ret;
1815 
1816 	/* Activate link_on bit and contender bit in our self ID packets.*/
1817 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
1818 	if (ret < 0)
1819 		return ret;
1820 
1821 	/*
1822 	 * When the link is not yet enabled, the atomic config rom
1823 	 * update mechanism described below in ohci_set_config_rom()
1824 	 * is not active.  We have to update ConfigRomHeader and
1825 	 * BusOptions manually, and the write to ConfigROMmap takes
1826 	 * effect immediately.  We tie this to the enabling of the
1827 	 * link, so we have a valid config rom before enabling - the
1828 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
1829 	 * values before enabling.
1830 	 *
1831 	 * However, when the ConfigROMmap is written, some controllers
1832 	 * always read back quadlets 0 and 2 from the config rom to
1833 	 * the ConfigRomHeader and BusOptions registers on bus reset.
1834 	 * They shouldn't do that in this initial case where the link
1835 	 * isn't enabled.  This means we have to use the same
1836 	 * workaround here, setting the bus header to 0 and then write
1837 	 * the right values in the bus reset tasklet.
1838 	 */
1839 
1840 	if (config_rom) {
1841 		ohci->next_config_rom =
1842 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1843 					   &ohci->next_config_rom_bus,
1844 					   GFP_KERNEL);
1845 		if (ohci->next_config_rom == NULL)
1846 			return -ENOMEM;
1847 
1848 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1849 	} else {
1850 		/*
1851 		 * In the suspend case, config_rom is NULL, which
1852 		 * means that we just reuse the old config rom.
1853 		 */
1854 		ohci->next_config_rom = ohci->config_rom;
1855 		ohci->next_config_rom_bus = ohci->config_rom_bus;
1856 	}
1857 
1858 	ohci->next_header = ohci->next_config_rom[0];
1859 	ohci->next_config_rom[0] = 0;
1860 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
1861 	reg_write(ohci, OHCI1394_BusOptions,
1862 		  be32_to_cpu(ohci->next_config_rom[2]));
1863 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
1864 
1865 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
1866 
1867 	if (!(ohci->quirks & QUIRK_NO_MSI))
1868 		pci_enable_msi(dev);
1869 	if (request_irq(dev->irq, irq_handler,
1870 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
1871 			ohci_driver_name, ohci)) {
1872 		fw_error("Failed to allocate interrupt %d.\n", dev->irq);
1873 		pci_disable_msi(dev);
1874 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1875 				  ohci->config_rom, ohci->config_rom_bus);
1876 		return -EIO;
1877 	}
1878 
1879 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
1880 		OHCI1394_RQPkt | OHCI1394_RSPkt |
1881 		OHCI1394_isochTx | OHCI1394_isochRx |
1882 		OHCI1394_postedWriteErr |
1883 		OHCI1394_selfIDComplete |
1884 		OHCI1394_regAccessFail |
1885 		OHCI1394_cycle64Seconds |
1886 		OHCI1394_cycleInconsistent | OHCI1394_cycleTooLong |
1887 		OHCI1394_masterIntEnable;
1888 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
1889 		irqs |= OHCI1394_busReset;
1890 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
1891 
1892 	reg_write(ohci, OHCI1394_HCControlSet,
1893 		  OHCI1394_HCControl_linkEnable |
1894 		  OHCI1394_HCControl_BIBimageValid);
1895 	flush_writes(ohci);
1896 
1897 	/* We are ready to go, reset bus to finish initialization. */
1898 	fw_schedule_bus_reset(&ohci->card, false, true);
1899 
1900 	return 0;
1901 }
1902 
1903 static int ohci_set_config_rom(struct fw_card *card,
1904 			       const __be32 *config_rom, size_t length)
1905 {
1906 	struct fw_ohci *ohci;
1907 	unsigned long flags;
1908 	int ret = -EBUSY;
1909 	__be32 *next_config_rom;
1910 	dma_addr_t uninitialized_var(next_config_rom_bus);
1911 
1912 	ohci = fw_ohci(card);
1913 
1914 	/*
1915 	 * When the OHCI controller is enabled, the config rom update
1916 	 * mechanism is a bit tricky, but easy enough to use.  See
1917 	 * section 5.5.6 in the OHCI specification.
1918 	 *
1919 	 * The OHCI controller caches the new config rom address in a
1920 	 * shadow register (ConfigROMmapNext) and needs a bus reset
1921 	 * for the changes to take place.  When the bus reset is
1922 	 * detected, the controller loads the new values for the
1923 	 * ConfigRomHeader and BusOptions registers from the specified
1924 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
1925 	 * shadow register. All automatically and atomically.
1926 	 *
1927 	 * Now, there's a twist to this story.  The automatic load of
1928 	 * ConfigRomHeader and BusOptions doesn't honor the
1929 	 * noByteSwapData bit, so with a be32 config rom, the
1930 	 * controller will load be32 values in to these registers
1931 	 * during the atomic update, even on litte endian
1932 	 * architectures.  The workaround we use is to put a 0 in the
1933 	 * header quadlet; 0 is endian agnostic and means that the
1934 	 * config rom isn't ready yet.  In the bus reset tasklet we
1935 	 * then set up the real values for the two registers.
1936 	 *
1937 	 * We use ohci->lock to avoid racing with the code that sets
1938 	 * ohci->next_config_rom to NULL (see bus_reset_tasklet).
1939 	 */
1940 
1941 	next_config_rom =
1942 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1943 				   &next_config_rom_bus, GFP_KERNEL);
1944 	if (next_config_rom == NULL)
1945 		return -ENOMEM;
1946 
1947 	spin_lock_irqsave(&ohci->lock, flags);
1948 
1949 	if (ohci->next_config_rom == NULL) {
1950 		ohci->next_config_rom = next_config_rom;
1951 		ohci->next_config_rom_bus = next_config_rom_bus;
1952 
1953 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1954 
1955 		ohci->next_header = config_rom[0];
1956 		ohci->next_config_rom[0] = 0;
1957 
1958 		reg_write(ohci, OHCI1394_ConfigROMmap,
1959 			  ohci->next_config_rom_bus);
1960 		ret = 0;
1961 	}
1962 
1963 	spin_unlock_irqrestore(&ohci->lock, flags);
1964 
1965 	/*
1966 	 * Now initiate a bus reset to have the changes take
1967 	 * effect. We clean up the old config rom memory and DMA
1968 	 * mappings in the bus reset tasklet, since the OHCI
1969 	 * controller could need to access it before the bus reset
1970 	 * takes effect.
1971 	 */
1972 	if (ret == 0)
1973 		fw_schedule_bus_reset(&ohci->card, true, true);
1974 	else
1975 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1976 				  next_config_rom, next_config_rom_bus);
1977 
1978 	return ret;
1979 }
1980 
1981 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
1982 {
1983 	struct fw_ohci *ohci = fw_ohci(card);
1984 
1985 	at_context_transmit(&ohci->at_request_ctx, packet);
1986 }
1987 
1988 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
1989 {
1990 	struct fw_ohci *ohci = fw_ohci(card);
1991 
1992 	at_context_transmit(&ohci->at_response_ctx, packet);
1993 }
1994 
1995 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
1996 {
1997 	struct fw_ohci *ohci = fw_ohci(card);
1998 	struct context *ctx = &ohci->at_request_ctx;
1999 	struct driver_data *driver_data = packet->driver_data;
2000 	int ret = -ENOENT;
2001 
2002 	tasklet_disable(&ctx->tasklet);
2003 
2004 	if (packet->ack != 0)
2005 		goto out;
2006 
2007 	if (packet->payload_mapped)
2008 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2009 				 packet->payload_length, DMA_TO_DEVICE);
2010 
2011 	log_ar_at_event('T', packet->speed, packet->header, 0x20);
2012 	driver_data->packet = NULL;
2013 	packet->ack = RCODE_CANCELLED;
2014 	packet->callback(packet, &ohci->card, packet->ack);
2015 	ret = 0;
2016  out:
2017 	tasklet_enable(&ctx->tasklet);
2018 
2019 	return ret;
2020 }
2021 
2022 static int ohci_enable_phys_dma(struct fw_card *card,
2023 				int node_id, int generation)
2024 {
2025 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2026 	return 0;
2027 #else
2028 	struct fw_ohci *ohci = fw_ohci(card);
2029 	unsigned long flags;
2030 	int n, ret = 0;
2031 
2032 	/*
2033 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2034 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2035 	 */
2036 
2037 	spin_lock_irqsave(&ohci->lock, flags);
2038 
2039 	if (ohci->generation != generation) {
2040 		ret = -ESTALE;
2041 		goto out;
2042 	}
2043 
2044 	/*
2045 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2046 	 * enabled for _all_ nodes on remote buses.
2047 	 */
2048 
2049 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2050 	if (n < 32)
2051 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2052 	else
2053 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2054 
2055 	flush_writes(ohci);
2056  out:
2057 	spin_unlock_irqrestore(&ohci->lock, flags);
2058 
2059 	return ret;
2060 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2061 }
2062 
2063 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2064 {
2065 	struct fw_ohci *ohci = fw_ohci(card);
2066 	unsigned long flags;
2067 	u32 value;
2068 
2069 	switch (csr_offset) {
2070 	case CSR_STATE_CLEAR:
2071 	case CSR_STATE_SET:
2072 		if (ohci->is_root &&
2073 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2074 		     OHCI1394_LinkControl_cycleMaster))
2075 			value = CSR_STATE_BIT_CMSTR;
2076 		else
2077 			value = 0;
2078 		if (ohci->csr_state_setclear_abdicate)
2079 			value |= CSR_STATE_BIT_ABDICATE;
2080 
2081 		return value;
2082 
2083 	case CSR_NODE_IDS:
2084 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2085 
2086 	case CSR_CYCLE_TIME:
2087 		return get_cycle_time(ohci);
2088 
2089 	case CSR_BUS_TIME:
2090 		/*
2091 		 * We might be called just after the cycle timer has wrapped
2092 		 * around but just before the cycle64Seconds handler, so we
2093 		 * better check here, too, if the bus time needs to be updated.
2094 		 */
2095 		spin_lock_irqsave(&ohci->lock, flags);
2096 		value = update_bus_time(ohci);
2097 		spin_unlock_irqrestore(&ohci->lock, flags);
2098 		return value;
2099 
2100 	case CSR_BUSY_TIMEOUT:
2101 		value = reg_read(ohci, OHCI1394_ATRetries);
2102 		return (value >> 4) & 0x0ffff00f;
2103 
2104 	case CSR_PRIORITY_BUDGET:
2105 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2106 			(ohci->pri_req_max << 8);
2107 
2108 	default:
2109 		WARN_ON(1);
2110 		return 0;
2111 	}
2112 }
2113 
2114 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2115 {
2116 	struct fw_ohci *ohci = fw_ohci(card);
2117 	unsigned long flags;
2118 
2119 	switch (csr_offset) {
2120 	case CSR_STATE_CLEAR:
2121 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2122 			reg_write(ohci, OHCI1394_LinkControlClear,
2123 				  OHCI1394_LinkControl_cycleMaster);
2124 			flush_writes(ohci);
2125 		}
2126 		if (value & CSR_STATE_BIT_ABDICATE)
2127 			ohci->csr_state_setclear_abdicate = false;
2128 		break;
2129 
2130 	case CSR_STATE_SET:
2131 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2132 			reg_write(ohci, OHCI1394_LinkControlSet,
2133 				  OHCI1394_LinkControl_cycleMaster);
2134 			flush_writes(ohci);
2135 		}
2136 		if (value & CSR_STATE_BIT_ABDICATE)
2137 			ohci->csr_state_setclear_abdicate = true;
2138 		break;
2139 
2140 	case CSR_NODE_IDS:
2141 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2142 		flush_writes(ohci);
2143 		break;
2144 
2145 	case CSR_CYCLE_TIME:
2146 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2147 		reg_write(ohci, OHCI1394_IntEventSet,
2148 			  OHCI1394_cycleInconsistent);
2149 		flush_writes(ohci);
2150 		break;
2151 
2152 	case CSR_BUS_TIME:
2153 		spin_lock_irqsave(&ohci->lock, flags);
2154 		ohci->bus_time = (ohci->bus_time & 0x7f) | (value & ~0x7f);
2155 		spin_unlock_irqrestore(&ohci->lock, flags);
2156 		break;
2157 
2158 	case CSR_BUSY_TIMEOUT:
2159 		value = (value & 0xf) | ((value & 0xf) << 4) |
2160 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2161 		reg_write(ohci, OHCI1394_ATRetries, value);
2162 		flush_writes(ohci);
2163 		break;
2164 
2165 	case CSR_PRIORITY_BUDGET:
2166 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2167 		flush_writes(ohci);
2168 		break;
2169 
2170 	default:
2171 		WARN_ON(1);
2172 		break;
2173 	}
2174 }
2175 
2176 static void copy_iso_headers(struct iso_context *ctx, void *p)
2177 {
2178 	int i = ctx->header_length;
2179 
2180 	if (i + ctx->base.header_size > PAGE_SIZE)
2181 		return;
2182 
2183 	/*
2184 	 * The iso header is byteswapped to little endian by
2185 	 * the controller, but the remaining header quadlets
2186 	 * are big endian.  We want to present all the headers
2187 	 * as big endian, so we have to swap the first quadlet.
2188 	 */
2189 	if (ctx->base.header_size > 0)
2190 		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
2191 	if (ctx->base.header_size > 4)
2192 		*(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
2193 	if (ctx->base.header_size > 8)
2194 		memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
2195 	ctx->header_length += ctx->base.header_size;
2196 }
2197 
2198 static int handle_ir_packet_per_buffer(struct context *context,
2199 				       struct descriptor *d,
2200 				       struct descriptor *last)
2201 {
2202 	struct iso_context *ctx =
2203 		container_of(context, struct iso_context, context);
2204 	struct descriptor *pd;
2205 	__le32 *ir_header;
2206 	void *p;
2207 
2208 	for (pd = d; pd <= last; pd++)
2209 		if (pd->transfer_status)
2210 			break;
2211 	if (pd > last)
2212 		/* Descriptor(s) not done yet, stop iteration */
2213 		return 0;
2214 
2215 	p = last + 1;
2216 	copy_iso_headers(ctx, p);
2217 
2218 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2219 		ir_header = (__le32 *) p;
2220 		ctx->base.callback.sc(&ctx->base,
2221 				      le32_to_cpu(ir_header[0]) & 0xffff,
2222 				      ctx->header_length, ctx->header,
2223 				      ctx->base.callback_data);
2224 		ctx->header_length = 0;
2225 	}
2226 
2227 	return 1;
2228 }
2229 
2230 /* d == last because each descriptor block is only a single descriptor. */
2231 static int handle_ir_buffer_fill(struct context *context,
2232 				 struct descriptor *d,
2233 				 struct descriptor *last)
2234 {
2235 	struct iso_context *ctx =
2236 		container_of(context, struct iso_context, context);
2237 
2238 	if (!last->transfer_status)
2239 		/* Descriptor(s) not done yet, stop iteration */
2240 		return 0;
2241 
2242 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS)
2243 		ctx->base.callback.mc(&ctx->base,
2244 				      le32_to_cpu(last->data_address) +
2245 				      le16_to_cpu(last->req_count) -
2246 				      le16_to_cpu(last->res_count),
2247 				      ctx->base.callback_data);
2248 
2249 	return 1;
2250 }
2251 
2252 static int handle_it_packet(struct context *context,
2253 			    struct descriptor *d,
2254 			    struct descriptor *last)
2255 {
2256 	struct iso_context *ctx =
2257 		container_of(context, struct iso_context, context);
2258 	int i;
2259 	struct descriptor *pd;
2260 
2261 	for (pd = d; pd <= last; pd++)
2262 		if (pd->transfer_status)
2263 			break;
2264 	if (pd > last)
2265 		/* Descriptor(s) not done yet, stop iteration */
2266 		return 0;
2267 
2268 	i = ctx->header_length;
2269 	if (i + 4 < PAGE_SIZE) {
2270 		/* Present this value as big-endian to match the receive code */
2271 		*(__be32 *)(ctx->header + i) = cpu_to_be32(
2272 				((u32)le16_to_cpu(pd->transfer_status) << 16) |
2273 				le16_to_cpu(pd->res_count));
2274 		ctx->header_length += 4;
2275 	}
2276 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2277 		ctx->base.callback.sc(&ctx->base, le16_to_cpu(last->res_count),
2278 				      ctx->header_length, ctx->header,
2279 				      ctx->base.callback_data);
2280 		ctx->header_length = 0;
2281 	}
2282 	return 1;
2283 }
2284 
2285 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2286 {
2287 	u32 hi = channels >> 32, lo = channels;
2288 
2289 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2290 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2291 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2292 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2293 	mmiowb();
2294 	ohci->mc_channels = channels;
2295 }
2296 
2297 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2298 				int type, int channel, size_t header_size)
2299 {
2300 	struct fw_ohci *ohci = fw_ohci(card);
2301 	struct iso_context *uninitialized_var(ctx);
2302 	descriptor_callback_t uninitialized_var(callback);
2303 	u64 *uninitialized_var(channels);
2304 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2305 	unsigned long flags;
2306 	int index, ret = -EBUSY;
2307 
2308 	spin_lock_irqsave(&ohci->lock, flags);
2309 
2310 	switch (type) {
2311 	case FW_ISO_CONTEXT_TRANSMIT:
2312 		mask     = &ohci->it_context_mask;
2313 		callback = handle_it_packet;
2314 		index    = ffs(*mask) - 1;
2315 		if (index >= 0) {
2316 			*mask &= ~(1 << index);
2317 			regs = OHCI1394_IsoXmitContextBase(index);
2318 			ctx  = &ohci->it_context_list[index];
2319 		}
2320 		break;
2321 
2322 	case FW_ISO_CONTEXT_RECEIVE:
2323 		channels = &ohci->ir_context_channels;
2324 		mask     = &ohci->ir_context_mask;
2325 		callback = handle_ir_packet_per_buffer;
2326 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2327 		if (index >= 0) {
2328 			*channels &= ~(1ULL << channel);
2329 			*mask     &= ~(1 << index);
2330 			regs = OHCI1394_IsoRcvContextBase(index);
2331 			ctx  = &ohci->ir_context_list[index];
2332 		}
2333 		break;
2334 
2335 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2336 		mask     = &ohci->ir_context_mask;
2337 		callback = handle_ir_buffer_fill;
2338 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2339 		if (index >= 0) {
2340 			ohci->mc_allocated = true;
2341 			*mask &= ~(1 << index);
2342 			regs = OHCI1394_IsoRcvContextBase(index);
2343 			ctx  = &ohci->ir_context_list[index];
2344 		}
2345 		break;
2346 
2347 	default:
2348 		index = -1;
2349 		ret = -ENOSYS;
2350 	}
2351 
2352 	spin_unlock_irqrestore(&ohci->lock, flags);
2353 
2354 	if (index < 0)
2355 		return ERR_PTR(ret);
2356 
2357 	memset(ctx, 0, sizeof(*ctx));
2358 	ctx->header_length = 0;
2359 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2360 	if (ctx->header == NULL) {
2361 		ret = -ENOMEM;
2362 		goto out;
2363 	}
2364 	ret = context_init(&ctx->context, ohci, regs, callback);
2365 	if (ret < 0)
2366 		goto out_with_header;
2367 
2368 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
2369 		set_multichannel_mask(ohci, 0);
2370 
2371 	return &ctx->base;
2372 
2373  out_with_header:
2374 	free_page((unsigned long)ctx->header);
2375  out:
2376 	spin_lock_irqsave(&ohci->lock, flags);
2377 
2378 	switch (type) {
2379 	case FW_ISO_CONTEXT_RECEIVE:
2380 		*channels |= 1ULL << channel;
2381 		break;
2382 
2383 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2384 		ohci->mc_allocated = false;
2385 		break;
2386 	}
2387 	*mask |= 1 << index;
2388 
2389 	spin_unlock_irqrestore(&ohci->lock, flags);
2390 
2391 	return ERR_PTR(ret);
2392 }
2393 
2394 static int ohci_start_iso(struct fw_iso_context *base,
2395 			  s32 cycle, u32 sync, u32 tags)
2396 {
2397 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2398 	struct fw_ohci *ohci = ctx->context.ohci;
2399 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2400 	int index;
2401 
2402 	switch (ctx->base.type) {
2403 	case FW_ISO_CONTEXT_TRANSMIT:
2404 		index = ctx - ohci->it_context_list;
2405 		match = 0;
2406 		if (cycle >= 0)
2407 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
2408 				(cycle & 0x7fff) << 16;
2409 
2410 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
2411 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
2412 		context_run(&ctx->context, match);
2413 		break;
2414 
2415 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2416 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
2417 		/* fall through */
2418 	case FW_ISO_CONTEXT_RECEIVE:
2419 		index = ctx - ohci->ir_context_list;
2420 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
2421 		if (cycle >= 0) {
2422 			match |= (cycle & 0x07fff) << 12;
2423 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
2424 		}
2425 
2426 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2427 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2428 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2429 		context_run(&ctx->context, control);
2430 		break;
2431 	}
2432 
2433 	return 0;
2434 }
2435 
2436 static int ohci_stop_iso(struct fw_iso_context *base)
2437 {
2438 	struct fw_ohci *ohci = fw_ohci(base->card);
2439 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2440 	int index;
2441 
2442 	switch (ctx->base.type) {
2443 	case FW_ISO_CONTEXT_TRANSMIT:
2444 		index = ctx - ohci->it_context_list;
2445 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2446 		break;
2447 
2448 	case FW_ISO_CONTEXT_RECEIVE:
2449 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2450 		index = ctx - ohci->ir_context_list;
2451 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2452 		break;
2453 	}
2454 	flush_writes(ohci);
2455 	context_stop(&ctx->context);
2456 
2457 	return 0;
2458 }
2459 
2460 static void ohci_free_iso_context(struct fw_iso_context *base)
2461 {
2462 	struct fw_ohci *ohci = fw_ohci(base->card);
2463 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2464 	unsigned long flags;
2465 	int index;
2466 
2467 	ohci_stop_iso(base);
2468 	context_release(&ctx->context);
2469 	free_page((unsigned long)ctx->header);
2470 
2471 	spin_lock_irqsave(&ohci->lock, flags);
2472 
2473 	switch (base->type) {
2474 	case FW_ISO_CONTEXT_TRANSMIT:
2475 		index = ctx - ohci->it_context_list;
2476 		ohci->it_context_mask |= 1 << index;
2477 		break;
2478 
2479 	case FW_ISO_CONTEXT_RECEIVE:
2480 		index = ctx - ohci->ir_context_list;
2481 		ohci->ir_context_mask |= 1 << index;
2482 		ohci->ir_context_channels |= 1ULL << base->channel;
2483 		break;
2484 
2485 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2486 		index = ctx - ohci->ir_context_list;
2487 		ohci->ir_context_mask |= 1 << index;
2488 		ohci->ir_context_channels |= ohci->mc_channels;
2489 		ohci->mc_channels = 0;
2490 		ohci->mc_allocated = false;
2491 		break;
2492 	}
2493 
2494 	spin_unlock_irqrestore(&ohci->lock, flags);
2495 }
2496 
2497 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
2498 {
2499 	struct fw_ohci *ohci = fw_ohci(base->card);
2500 	unsigned long flags;
2501 	int ret;
2502 
2503 	switch (base->type) {
2504 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2505 
2506 		spin_lock_irqsave(&ohci->lock, flags);
2507 
2508 		/* Don't allow multichannel to grab other contexts' channels. */
2509 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
2510 			*channels = ohci->ir_context_channels;
2511 			ret = -EBUSY;
2512 		} else {
2513 			set_multichannel_mask(ohci, *channels);
2514 			ret = 0;
2515 		}
2516 
2517 		spin_unlock_irqrestore(&ohci->lock, flags);
2518 
2519 		break;
2520 	default:
2521 		ret = -EINVAL;
2522 	}
2523 
2524 	return ret;
2525 }
2526 
2527 static int queue_iso_transmit(struct iso_context *ctx,
2528 			      struct fw_iso_packet *packet,
2529 			      struct fw_iso_buffer *buffer,
2530 			      unsigned long payload)
2531 {
2532 	struct descriptor *d, *last, *pd;
2533 	struct fw_iso_packet *p;
2534 	__le32 *header;
2535 	dma_addr_t d_bus, page_bus;
2536 	u32 z, header_z, payload_z, irq;
2537 	u32 payload_index, payload_end_index, next_page_index;
2538 	int page, end_page, i, length, offset;
2539 
2540 	p = packet;
2541 	payload_index = payload;
2542 
2543 	if (p->skip)
2544 		z = 1;
2545 	else
2546 		z = 2;
2547 	if (p->header_length > 0)
2548 		z++;
2549 
2550 	/* Determine the first page the payload isn't contained in. */
2551 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2552 	if (p->payload_length > 0)
2553 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
2554 	else
2555 		payload_z = 0;
2556 
2557 	z += payload_z;
2558 
2559 	/* Get header size in number of descriptors. */
2560 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2561 
2562 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2563 	if (d == NULL)
2564 		return -ENOMEM;
2565 
2566 	if (!p->skip) {
2567 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2568 		d[0].req_count = cpu_to_le16(8);
2569 		/*
2570 		 * Link the skip address to this descriptor itself.  This causes
2571 		 * a context to skip a cycle whenever lost cycles or FIFO
2572 		 * overruns occur, without dropping the data.  The application
2573 		 * should then decide whether this is an error condition or not.
2574 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
2575 		 */
2576 		d[0].branch_address = cpu_to_le32(d_bus | z);
2577 
2578 		header = (__le32 *) &d[1];
2579 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2580 					IT_HEADER_TAG(p->tag) |
2581 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2582 					IT_HEADER_CHANNEL(ctx->base.channel) |
2583 					IT_HEADER_SPEED(ctx->base.speed));
2584 		header[1] =
2585 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2586 							  p->payload_length));
2587 	}
2588 
2589 	if (p->header_length > 0) {
2590 		d[2].req_count    = cpu_to_le16(p->header_length);
2591 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2592 		memcpy(&d[z], p->header, p->header_length);
2593 	}
2594 
2595 	pd = d + z - payload_z;
2596 	payload_end_index = payload_index + p->payload_length;
2597 	for (i = 0; i < payload_z; i++) {
2598 		page               = payload_index >> PAGE_SHIFT;
2599 		offset             = payload_index & ~PAGE_MASK;
2600 		next_page_index    = (page + 1) << PAGE_SHIFT;
2601 		length             =
2602 			min(next_page_index, payload_end_index) - payload_index;
2603 		pd[i].req_count    = cpu_to_le16(length);
2604 
2605 		page_bus = page_private(buffer->pages[page]);
2606 		pd[i].data_address = cpu_to_le32(page_bus + offset);
2607 
2608 		payload_index += length;
2609 	}
2610 
2611 	if (p->interrupt)
2612 		irq = DESCRIPTOR_IRQ_ALWAYS;
2613 	else
2614 		irq = DESCRIPTOR_NO_IRQ;
2615 
2616 	last = z == 2 ? d : d + z - 1;
2617 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2618 				     DESCRIPTOR_STATUS |
2619 				     DESCRIPTOR_BRANCH_ALWAYS |
2620 				     irq);
2621 
2622 	context_append(&ctx->context, d, z, header_z);
2623 
2624 	return 0;
2625 }
2626 
2627 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
2628 				       struct fw_iso_packet *packet,
2629 				       struct fw_iso_buffer *buffer,
2630 				       unsigned long payload)
2631 {
2632 	struct descriptor *d, *pd;
2633 	dma_addr_t d_bus, page_bus;
2634 	u32 z, header_z, rest;
2635 	int i, j, length;
2636 	int page, offset, packet_count, header_size, payload_per_buffer;
2637 
2638 	/*
2639 	 * The OHCI controller puts the isochronous header and trailer in the
2640 	 * buffer, so we need at least 8 bytes.
2641 	 */
2642 	packet_count = packet->header_length / ctx->base.header_size;
2643 	header_size  = max(ctx->base.header_size, (size_t)8);
2644 
2645 	/* Get header size in number of descriptors. */
2646 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2647 	page     = payload >> PAGE_SHIFT;
2648 	offset   = payload & ~PAGE_MASK;
2649 	payload_per_buffer = packet->payload_length / packet_count;
2650 
2651 	for (i = 0; i < packet_count; i++) {
2652 		/* d points to the header descriptor */
2653 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
2654 		d = context_get_descriptors(&ctx->context,
2655 				z + header_z, &d_bus);
2656 		if (d == NULL)
2657 			return -ENOMEM;
2658 
2659 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
2660 					      DESCRIPTOR_INPUT_MORE);
2661 		if (packet->skip && i == 0)
2662 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2663 		d->req_count    = cpu_to_le16(header_size);
2664 		d->res_count    = d->req_count;
2665 		d->transfer_status = 0;
2666 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
2667 
2668 		rest = payload_per_buffer;
2669 		pd = d;
2670 		for (j = 1; j < z; j++) {
2671 			pd++;
2672 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2673 						  DESCRIPTOR_INPUT_MORE);
2674 
2675 			if (offset + rest < PAGE_SIZE)
2676 				length = rest;
2677 			else
2678 				length = PAGE_SIZE - offset;
2679 			pd->req_count = cpu_to_le16(length);
2680 			pd->res_count = pd->req_count;
2681 			pd->transfer_status = 0;
2682 
2683 			page_bus = page_private(buffer->pages[page]);
2684 			pd->data_address = cpu_to_le32(page_bus + offset);
2685 
2686 			offset = (offset + length) & ~PAGE_MASK;
2687 			rest -= length;
2688 			if (offset == 0)
2689 				page++;
2690 		}
2691 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2692 					  DESCRIPTOR_INPUT_LAST |
2693 					  DESCRIPTOR_BRANCH_ALWAYS);
2694 		if (packet->interrupt && i == packet_count - 1)
2695 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2696 
2697 		context_append(&ctx->context, d, z, header_z);
2698 	}
2699 
2700 	return 0;
2701 }
2702 
2703 static int queue_iso_buffer_fill(struct iso_context *ctx,
2704 				 struct fw_iso_packet *packet,
2705 				 struct fw_iso_buffer *buffer,
2706 				 unsigned long payload)
2707 {
2708 	struct descriptor *d;
2709 	dma_addr_t d_bus, page_bus;
2710 	int page, offset, rest, z, i, length;
2711 
2712 	page   = payload >> PAGE_SHIFT;
2713 	offset = payload & ~PAGE_MASK;
2714 	rest   = packet->payload_length;
2715 
2716 	/* We need one descriptor for each page in the buffer. */
2717 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
2718 
2719 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
2720 		return -EFAULT;
2721 
2722 	for (i = 0; i < z; i++) {
2723 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
2724 		if (d == NULL)
2725 			return -ENOMEM;
2726 
2727 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
2728 					 DESCRIPTOR_BRANCH_ALWAYS);
2729 		if (packet->skip && i == 0)
2730 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2731 		if (packet->interrupt && i == z - 1)
2732 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2733 
2734 		if (offset + rest < PAGE_SIZE)
2735 			length = rest;
2736 		else
2737 			length = PAGE_SIZE - offset;
2738 		d->req_count = cpu_to_le16(length);
2739 		d->res_count = d->req_count;
2740 		d->transfer_status = 0;
2741 
2742 		page_bus = page_private(buffer->pages[page]);
2743 		d->data_address = cpu_to_le32(page_bus + offset);
2744 
2745 		rest -= length;
2746 		offset = 0;
2747 		page++;
2748 
2749 		context_append(&ctx->context, d, 1, 0);
2750 	}
2751 
2752 	return 0;
2753 }
2754 
2755 static int ohci_queue_iso(struct fw_iso_context *base,
2756 			  struct fw_iso_packet *packet,
2757 			  struct fw_iso_buffer *buffer,
2758 			  unsigned long payload)
2759 {
2760 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2761 	unsigned long flags;
2762 	int ret = -ENOSYS;
2763 
2764 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
2765 	switch (base->type) {
2766 	case FW_ISO_CONTEXT_TRANSMIT:
2767 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
2768 		break;
2769 	case FW_ISO_CONTEXT_RECEIVE:
2770 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
2771 		break;
2772 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2773 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
2774 		break;
2775 	}
2776 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
2777 
2778 	return ret;
2779 }
2780 
2781 static const struct fw_card_driver ohci_driver = {
2782 	.enable			= ohci_enable,
2783 	.read_phy_reg		= ohci_read_phy_reg,
2784 	.update_phy_reg		= ohci_update_phy_reg,
2785 	.set_config_rom		= ohci_set_config_rom,
2786 	.send_request		= ohci_send_request,
2787 	.send_response		= ohci_send_response,
2788 	.cancel_packet		= ohci_cancel_packet,
2789 	.enable_phys_dma	= ohci_enable_phys_dma,
2790 	.read_csr		= ohci_read_csr,
2791 	.write_csr		= ohci_write_csr,
2792 
2793 	.allocate_iso_context	= ohci_allocate_iso_context,
2794 	.free_iso_context	= ohci_free_iso_context,
2795 	.set_iso_channels	= ohci_set_iso_channels,
2796 	.queue_iso		= ohci_queue_iso,
2797 	.start_iso		= ohci_start_iso,
2798 	.stop_iso		= ohci_stop_iso,
2799 };
2800 
2801 #ifdef CONFIG_PPC_PMAC
2802 static void pmac_ohci_on(struct pci_dev *dev)
2803 {
2804 	if (machine_is(powermac)) {
2805 		struct device_node *ofn = pci_device_to_OF_node(dev);
2806 
2807 		if (ofn) {
2808 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
2809 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
2810 		}
2811 	}
2812 }
2813 
2814 static void pmac_ohci_off(struct pci_dev *dev)
2815 {
2816 	if (machine_is(powermac)) {
2817 		struct device_node *ofn = pci_device_to_OF_node(dev);
2818 
2819 		if (ofn) {
2820 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
2821 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
2822 		}
2823 	}
2824 }
2825 #else
2826 static inline void pmac_ohci_on(struct pci_dev *dev) {}
2827 static inline void pmac_ohci_off(struct pci_dev *dev) {}
2828 #endif /* CONFIG_PPC_PMAC */
2829 
2830 static int __devinit pci_probe(struct pci_dev *dev,
2831 			       const struct pci_device_id *ent)
2832 {
2833 	struct fw_ohci *ohci;
2834 	u32 bus_options, max_receive, link_speed, version, link_enh;
2835 	u64 guid;
2836 	int i, err, n_ir, n_it;
2837 	size_t size;
2838 
2839 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
2840 	if (ohci == NULL) {
2841 		err = -ENOMEM;
2842 		goto fail;
2843 	}
2844 
2845 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
2846 
2847 	pmac_ohci_on(dev);
2848 
2849 	err = pci_enable_device(dev);
2850 	if (err) {
2851 		fw_error("Failed to enable OHCI hardware\n");
2852 		goto fail_free;
2853 	}
2854 
2855 	pci_set_master(dev);
2856 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
2857 	pci_set_drvdata(dev, ohci);
2858 
2859 	spin_lock_init(&ohci->lock);
2860 	mutex_init(&ohci->phy_reg_mutex);
2861 
2862 	tasklet_init(&ohci->bus_reset_tasklet,
2863 		     bus_reset_tasklet, (unsigned long)ohci);
2864 
2865 	err = pci_request_region(dev, 0, ohci_driver_name);
2866 	if (err) {
2867 		fw_error("MMIO resource unavailable\n");
2868 		goto fail_disable;
2869 	}
2870 
2871 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
2872 	if (ohci->registers == NULL) {
2873 		fw_error("Failed to remap registers\n");
2874 		err = -ENXIO;
2875 		goto fail_iomem;
2876 	}
2877 
2878 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
2879 		if (ohci_quirks[i].vendor == dev->vendor &&
2880 		    (ohci_quirks[i].device == dev->device ||
2881 		     ohci_quirks[i].device == (unsigned short)PCI_ANY_ID)) {
2882 			ohci->quirks = ohci_quirks[i].flags;
2883 			break;
2884 		}
2885 	if (param_quirks)
2886 		ohci->quirks = param_quirks;
2887 
2888 	/* TI OHCI-Lynx and compatible: set recommended configuration bits. */
2889 	if (dev->vendor == PCI_VENDOR_ID_TI) {
2890 		pci_read_config_dword(dev, PCI_CFG_TI_LinkEnh, &link_enh);
2891 
2892 		/* adjust latency of ATx FIFO: use 1.7 KB threshold */
2893 		link_enh &= ~TI_LinkEnh_atx_thresh_mask;
2894 		link_enh |= TI_LinkEnh_atx_thresh_1_7K;
2895 
2896 		/* use priority arbitration for asynchronous responses */
2897 		link_enh |= TI_LinkEnh_enab_unfair;
2898 
2899 		/* required for aPhyEnhanceEnable to work */
2900 		link_enh |= TI_LinkEnh_enab_accel;
2901 
2902 		pci_write_config_dword(dev, PCI_CFG_TI_LinkEnh, link_enh);
2903 	}
2904 
2905 	ar_context_init(&ohci->ar_request_ctx, ohci,
2906 			OHCI1394_AsReqRcvContextControlSet);
2907 
2908 	ar_context_init(&ohci->ar_response_ctx, ohci,
2909 			OHCI1394_AsRspRcvContextControlSet);
2910 
2911 	context_init(&ohci->at_request_ctx, ohci,
2912 		     OHCI1394_AsReqTrContextControlSet, handle_at_packet);
2913 
2914 	context_init(&ohci->at_response_ctx, ohci,
2915 		     OHCI1394_AsRspTrContextControlSet, handle_at_packet);
2916 
2917 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
2918 	ohci->ir_context_channels = ~0ULL;
2919 	ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
2920 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
2921 	n_ir = hweight32(ohci->ir_context_mask);
2922 	size = sizeof(struct iso_context) * n_ir;
2923 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
2924 
2925 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
2926 	ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
2927 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
2928 	n_it = hweight32(ohci->it_context_mask);
2929 	size = sizeof(struct iso_context) * n_it;
2930 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
2931 
2932 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
2933 		err = -ENOMEM;
2934 		goto fail_contexts;
2935 	}
2936 
2937 	/* self-id dma buffer allocation */
2938 	ohci->self_id_cpu = dma_alloc_coherent(ohci->card.device,
2939 					       SELF_ID_BUF_SIZE,
2940 					       &ohci->self_id_bus,
2941 					       GFP_KERNEL);
2942 	if (ohci->self_id_cpu == NULL) {
2943 		err = -ENOMEM;
2944 		goto fail_contexts;
2945 	}
2946 
2947 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
2948 	max_receive = (bus_options >> 12) & 0xf;
2949 	link_speed = bus_options & 0x7;
2950 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
2951 		reg_read(ohci, OHCI1394_GUIDLo);
2952 
2953 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
2954 	if (err)
2955 		goto fail_self_id;
2956 
2957 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2958 	fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
2959 		  "%d IR + %d IT contexts, quirks 0x%x\n",
2960 		  dev_name(&dev->dev), version >> 16, version & 0xff,
2961 		  n_ir, n_it, ohci->quirks);
2962 
2963 	return 0;
2964 
2965  fail_self_id:
2966 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2967 			  ohci->self_id_cpu, ohci->self_id_bus);
2968  fail_contexts:
2969 	kfree(ohci->ir_context_list);
2970 	kfree(ohci->it_context_list);
2971 	context_release(&ohci->at_response_ctx);
2972 	context_release(&ohci->at_request_ctx);
2973 	ar_context_release(&ohci->ar_response_ctx);
2974 	ar_context_release(&ohci->ar_request_ctx);
2975 	pci_iounmap(dev, ohci->registers);
2976  fail_iomem:
2977 	pci_release_region(dev, 0);
2978  fail_disable:
2979 	pci_disable_device(dev);
2980  fail_free:
2981 	kfree(&ohci->card);
2982 	pmac_ohci_off(dev);
2983  fail:
2984 	if (err == -ENOMEM)
2985 		fw_error("Out of memory\n");
2986 
2987 	return err;
2988 }
2989 
2990 static void pci_remove(struct pci_dev *dev)
2991 {
2992 	struct fw_ohci *ohci;
2993 
2994 	ohci = pci_get_drvdata(dev);
2995 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2996 	flush_writes(ohci);
2997 	fw_core_remove_card(&ohci->card);
2998 
2999 	/*
3000 	 * FIXME: Fail all pending packets here, now that the upper
3001 	 * layers can't queue any more.
3002 	 */
3003 
3004 	software_reset(ohci);
3005 	free_irq(dev->irq, ohci);
3006 
3007 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3008 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3009 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3010 	if (ohci->config_rom)
3011 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3012 				  ohci->config_rom, ohci->config_rom_bus);
3013 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
3014 			  ohci->self_id_cpu, ohci->self_id_bus);
3015 	ar_context_release(&ohci->ar_request_ctx);
3016 	ar_context_release(&ohci->ar_response_ctx);
3017 	context_release(&ohci->at_request_ctx);
3018 	context_release(&ohci->at_response_ctx);
3019 	kfree(ohci->it_context_list);
3020 	kfree(ohci->ir_context_list);
3021 	pci_disable_msi(dev);
3022 	pci_iounmap(dev, ohci->registers);
3023 	pci_release_region(dev, 0);
3024 	pci_disable_device(dev);
3025 	kfree(&ohci->card);
3026 	pmac_ohci_off(dev);
3027 
3028 	fw_notify("Removed fw-ohci device.\n");
3029 }
3030 
3031 #ifdef CONFIG_PM
3032 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3033 {
3034 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3035 	int err;
3036 
3037 	software_reset(ohci);
3038 	free_irq(dev->irq, ohci);
3039 	pci_disable_msi(dev);
3040 	err = pci_save_state(dev);
3041 	if (err) {
3042 		fw_error("pci_save_state failed\n");
3043 		return err;
3044 	}
3045 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3046 	if (err)
3047 		fw_error("pci_set_power_state failed with %d\n", err);
3048 	pmac_ohci_off(dev);
3049 
3050 	return 0;
3051 }
3052 
3053 static int pci_resume(struct pci_dev *dev)
3054 {
3055 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3056 	int err;
3057 
3058 	pmac_ohci_on(dev);
3059 	pci_set_power_state(dev, PCI_D0);
3060 	pci_restore_state(dev);
3061 	err = pci_enable_device(dev);
3062 	if (err) {
3063 		fw_error("pci_enable_device failed\n");
3064 		return err;
3065 	}
3066 
3067 	return ohci_enable(&ohci->card, NULL, 0);
3068 }
3069 #endif
3070 
3071 static const struct pci_device_id pci_table[] = {
3072 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3073 	{ }
3074 };
3075 
3076 MODULE_DEVICE_TABLE(pci, pci_table);
3077 
3078 static struct pci_driver fw_ohci_pci_driver = {
3079 	.name		= ohci_driver_name,
3080 	.id_table	= pci_table,
3081 	.probe		= pci_probe,
3082 	.remove		= pci_remove,
3083 #ifdef CONFIG_PM
3084 	.resume		= pci_resume,
3085 	.suspend	= pci_suspend,
3086 #endif
3087 };
3088 
3089 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3090 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3091 MODULE_LICENSE("GPL");
3092 
3093 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3094 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3095 MODULE_ALIAS("ohci1394");
3096 #endif
3097 
3098 static int __init fw_ohci_init(void)
3099 {
3100 	return pci_register_driver(&fw_ohci_pci_driver);
3101 }
3102 
3103 static void __exit fw_ohci_cleanup(void)
3104 {
3105 	pci_unregister_driver(&fw_ohci_pci_driver);
3106 }
3107 
3108 module_init(fw_ohci_init);
3109 module_exit(fw_ohci_cleanup);
3110