xref: /linux/drivers/firewire/ohci.c (revision 606b2f490fb80e55d05cf0e6cec0b6c0ff0fc18f)
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 	 * Several controllers, notably from NEC and VIA, forget to
698 	 * write ack_complete status at PHY packet reception.
699 	 */
700 	if (evt == OHCI1394_evt_no_status &&
701 	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
702 		p.ack = ACK_COMPLETE;
703 
704 	/*
705 	 * The OHCI bus reset handler synthesizes a PHY packet with
706 	 * the new generation number when a bus reset happens (see
707 	 * section 8.4.2.3).  This helps us determine when a request
708 	 * was received and make sure we send the response in the same
709 	 * generation.  We only need this for requests; for responses
710 	 * we use the unique tlabel for finding the matching
711 	 * request.
712 	 *
713 	 * Alas some chips sometimes emit bus reset packets with a
714 	 * wrong generation.  We set the correct generation for these
715 	 * at a slightly incorrect time (in bus_reset_tasklet).
716 	 */
717 	if (evt == OHCI1394_evt_bus_reset) {
718 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
719 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
720 	} else if (ctx == &ohci->ar_request_ctx) {
721 		fw_core_handle_request(&ohci->card, &p);
722 	} else {
723 		fw_core_handle_response(&ohci->card, &p);
724 	}
725 
726 	return buffer + length + 1;
727 }
728 
729 static void ar_context_tasklet(unsigned long data)
730 {
731 	struct ar_context *ctx = (struct ar_context *)data;
732 	struct fw_ohci *ohci = ctx->ohci;
733 	struct ar_buffer *ab;
734 	struct descriptor *d;
735 	void *buffer, *end;
736 
737 	ab = ctx->current_buffer;
738 	d = &ab->descriptor;
739 
740 	if (d->res_count == 0) {
741 		size_t size, rest, offset;
742 		dma_addr_t start_bus;
743 		void *start;
744 
745 		/*
746 		 * This descriptor is finished and we may have a
747 		 * packet split across this and the next buffer. We
748 		 * reuse the page for reassembling the split packet.
749 		 */
750 
751 		offset = offsetof(struct ar_buffer, data);
752 		start = buffer = ab;
753 		start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
754 
755 		ab = ab->next;
756 		d = &ab->descriptor;
757 		size = buffer + PAGE_SIZE - ctx->pointer;
758 		rest = le16_to_cpu(d->req_count) - le16_to_cpu(d->res_count);
759 		memmove(buffer, ctx->pointer, size);
760 		memcpy(buffer + size, ab->data, rest);
761 		ctx->current_buffer = ab;
762 		ctx->pointer = (void *) ab->data + rest;
763 		end = buffer + size + rest;
764 
765 		while (buffer < end)
766 			buffer = handle_ar_packet(ctx, buffer);
767 
768 		dma_free_coherent(ohci->card.device, PAGE_SIZE,
769 				  start, start_bus);
770 		ar_context_add_page(ctx);
771 	} else {
772 		buffer = ctx->pointer;
773 		ctx->pointer = end =
774 			(void *) ab + PAGE_SIZE - le16_to_cpu(d->res_count);
775 
776 		while (buffer < end)
777 			buffer = handle_ar_packet(ctx, buffer);
778 	}
779 }
780 
781 static int ar_context_init(struct ar_context *ctx,
782 			   struct fw_ohci *ohci, u32 regs)
783 {
784 	struct ar_buffer ab;
785 
786 	ctx->regs        = regs;
787 	ctx->ohci        = ohci;
788 	ctx->last_buffer = &ab;
789 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
790 
791 	ar_context_add_page(ctx);
792 	ar_context_add_page(ctx);
793 	ctx->current_buffer = ab.next;
794 	ctx->pointer = ctx->current_buffer->data;
795 
796 	return 0;
797 }
798 
799 static void ar_context_run(struct ar_context *ctx)
800 {
801 	struct ar_buffer *ab = ctx->current_buffer;
802 	dma_addr_t ab_bus;
803 	size_t offset;
804 
805 	offset = offsetof(struct ar_buffer, data);
806 	ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
807 
808 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ab_bus | 1);
809 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
810 	flush_writes(ctx->ohci);
811 }
812 
813 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
814 {
815 	int b, key;
816 
817 	b   = (le16_to_cpu(d->control) & DESCRIPTOR_BRANCH_ALWAYS) >> 2;
818 	key = (le16_to_cpu(d->control) & DESCRIPTOR_KEY_IMMEDIATE) >> 8;
819 
820 	/* figure out which descriptor the branch address goes in */
821 	if (z == 2 && (b == 3 || key == 2))
822 		return d;
823 	else
824 		return d + z - 1;
825 }
826 
827 static void context_tasklet(unsigned long data)
828 {
829 	struct context *ctx = (struct context *) data;
830 	struct descriptor *d, *last;
831 	u32 address;
832 	int z;
833 	struct descriptor_buffer *desc;
834 
835 	desc = list_entry(ctx->buffer_list.next,
836 			struct descriptor_buffer, list);
837 	last = ctx->last;
838 	while (last->branch_address != 0) {
839 		struct descriptor_buffer *old_desc = desc;
840 		address = le32_to_cpu(last->branch_address);
841 		z = address & 0xf;
842 		address &= ~0xf;
843 
844 		/* If the branch address points to a buffer outside of the
845 		 * current buffer, advance to the next buffer. */
846 		if (address < desc->buffer_bus ||
847 				address >= desc->buffer_bus + desc->used)
848 			desc = list_entry(desc->list.next,
849 					struct descriptor_buffer, list);
850 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
851 		last = find_branch_descriptor(d, z);
852 
853 		if (!ctx->callback(ctx, d, last))
854 			break;
855 
856 		if (old_desc != desc) {
857 			/* If we've advanced to the next buffer, move the
858 			 * previous buffer to the free list. */
859 			unsigned long flags;
860 			old_desc->used = 0;
861 			spin_lock_irqsave(&ctx->ohci->lock, flags);
862 			list_move_tail(&old_desc->list, &ctx->buffer_list);
863 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
864 		}
865 		ctx->last = last;
866 	}
867 }
868 
869 /*
870  * Allocate a new buffer and add it to the list of free buffers for this
871  * context.  Must be called with ohci->lock held.
872  */
873 static int context_add_buffer(struct context *ctx)
874 {
875 	struct descriptor_buffer *desc;
876 	dma_addr_t uninitialized_var(bus_addr);
877 	int offset;
878 
879 	/*
880 	 * 16MB of descriptors should be far more than enough for any DMA
881 	 * program.  This will catch run-away userspace or DoS attacks.
882 	 */
883 	if (ctx->total_allocation >= 16*1024*1024)
884 		return -ENOMEM;
885 
886 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
887 			&bus_addr, GFP_ATOMIC);
888 	if (!desc)
889 		return -ENOMEM;
890 
891 	offset = (void *)&desc->buffer - (void *)desc;
892 	desc->buffer_size = PAGE_SIZE - offset;
893 	desc->buffer_bus = bus_addr + offset;
894 	desc->used = 0;
895 
896 	list_add_tail(&desc->list, &ctx->buffer_list);
897 	ctx->total_allocation += PAGE_SIZE;
898 
899 	return 0;
900 }
901 
902 static int context_init(struct context *ctx, struct fw_ohci *ohci,
903 			u32 regs, descriptor_callback_t callback)
904 {
905 	ctx->ohci = ohci;
906 	ctx->regs = regs;
907 	ctx->total_allocation = 0;
908 
909 	INIT_LIST_HEAD(&ctx->buffer_list);
910 	if (context_add_buffer(ctx) < 0)
911 		return -ENOMEM;
912 
913 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
914 			struct descriptor_buffer, list);
915 
916 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
917 	ctx->callback = callback;
918 
919 	/*
920 	 * We put a dummy descriptor in the buffer that has a NULL
921 	 * branch address and looks like it's been sent.  That way we
922 	 * have a descriptor to append DMA programs to.
923 	 */
924 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
925 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
926 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
927 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
928 	ctx->last = ctx->buffer_tail->buffer;
929 	ctx->prev = ctx->buffer_tail->buffer;
930 
931 	return 0;
932 }
933 
934 static void context_release(struct context *ctx)
935 {
936 	struct fw_card *card = &ctx->ohci->card;
937 	struct descriptor_buffer *desc, *tmp;
938 
939 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
940 		dma_free_coherent(card->device, PAGE_SIZE, desc,
941 			desc->buffer_bus -
942 			((void *)&desc->buffer - (void *)desc));
943 }
944 
945 /* Must be called with ohci->lock held */
946 static struct descriptor *context_get_descriptors(struct context *ctx,
947 						  int z, dma_addr_t *d_bus)
948 {
949 	struct descriptor *d = NULL;
950 	struct descriptor_buffer *desc = ctx->buffer_tail;
951 
952 	if (z * sizeof(*d) > desc->buffer_size)
953 		return NULL;
954 
955 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
956 		/* No room for the descriptor in this buffer, so advance to the
957 		 * next one. */
958 
959 		if (desc->list.next == &ctx->buffer_list) {
960 			/* If there is no free buffer next in the list,
961 			 * allocate one. */
962 			if (context_add_buffer(ctx) < 0)
963 				return NULL;
964 		}
965 		desc = list_entry(desc->list.next,
966 				struct descriptor_buffer, list);
967 		ctx->buffer_tail = desc;
968 	}
969 
970 	d = desc->buffer + desc->used / sizeof(*d);
971 	memset(d, 0, z * sizeof(*d));
972 	*d_bus = desc->buffer_bus + desc->used;
973 
974 	return d;
975 }
976 
977 static void context_run(struct context *ctx, u32 extra)
978 {
979 	struct fw_ohci *ohci = ctx->ohci;
980 
981 	reg_write(ohci, COMMAND_PTR(ctx->regs),
982 		  le32_to_cpu(ctx->last->branch_address));
983 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
984 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
985 	flush_writes(ohci);
986 }
987 
988 static void context_append(struct context *ctx,
989 			   struct descriptor *d, int z, int extra)
990 {
991 	dma_addr_t d_bus;
992 	struct descriptor_buffer *desc = ctx->buffer_tail;
993 
994 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
995 
996 	desc->used += (z + extra) * sizeof(*d);
997 
998 	wmb(); /* finish init of new descriptors before branch_address update */
999 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1000 	ctx->prev = find_branch_descriptor(d, z);
1001 
1002 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1003 	flush_writes(ctx->ohci);
1004 }
1005 
1006 static void context_stop(struct context *ctx)
1007 {
1008 	u32 reg;
1009 	int i;
1010 
1011 	reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1012 	flush_writes(ctx->ohci);
1013 
1014 	for (i = 0; i < 10; i++) {
1015 		reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1016 		if ((reg & CONTEXT_ACTIVE) == 0)
1017 			return;
1018 
1019 		mdelay(1);
1020 	}
1021 	fw_error("Error: DMA context still active (0x%08x)\n", reg);
1022 }
1023 
1024 struct driver_data {
1025 	struct fw_packet *packet;
1026 };
1027 
1028 /*
1029  * This function apppends a packet to the DMA queue for transmission.
1030  * Must always be called with the ochi->lock held to ensure proper
1031  * generation handling and locking around packet queue manipulation.
1032  */
1033 static int at_context_queue_packet(struct context *ctx,
1034 				   struct fw_packet *packet)
1035 {
1036 	struct fw_ohci *ohci = ctx->ohci;
1037 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1038 	struct driver_data *driver_data;
1039 	struct descriptor *d, *last;
1040 	__le32 *header;
1041 	int z, tcode;
1042 	u32 reg;
1043 
1044 	d = context_get_descriptors(ctx, 4, &d_bus);
1045 	if (d == NULL) {
1046 		packet->ack = RCODE_SEND_ERROR;
1047 		return -1;
1048 	}
1049 
1050 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1051 	d[0].res_count = cpu_to_le16(packet->timestamp);
1052 
1053 	/*
1054 	 * The DMA format for asyncronous link packets is different
1055 	 * from the IEEE1394 layout, so shift the fields around
1056 	 * accordingly.  If header_length is 8, it's a PHY packet, to
1057 	 * which we need to prepend an extra quadlet.
1058 	 */
1059 
1060 	header = (__le32 *) &d[1];
1061 	switch (packet->header_length) {
1062 	case 16:
1063 	case 12:
1064 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1065 					(packet->speed << 16));
1066 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1067 					(packet->header[0] & 0xffff0000));
1068 		header[2] = cpu_to_le32(packet->header[2]);
1069 
1070 		tcode = (packet->header[0] >> 4) & 0x0f;
1071 		if (TCODE_IS_BLOCK_PACKET(tcode))
1072 			header[3] = cpu_to_le32(packet->header[3]);
1073 		else
1074 			header[3] = (__force __le32) packet->header[3];
1075 
1076 		d[0].req_count = cpu_to_le16(packet->header_length);
1077 		break;
1078 
1079 	case 8:
1080 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1081 					(packet->speed << 16));
1082 		header[1] = cpu_to_le32(packet->header[0]);
1083 		header[2] = cpu_to_le32(packet->header[1]);
1084 		d[0].req_count = cpu_to_le16(12);
1085 
1086 		if (is_ping_packet(packet->header))
1087 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1088 		break;
1089 
1090 	case 4:
1091 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1092 					(packet->speed << 16));
1093 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1094 		d[0].req_count = cpu_to_le16(8);
1095 		break;
1096 
1097 	default:
1098 		/* BUG(); */
1099 		packet->ack = RCODE_SEND_ERROR;
1100 		return -1;
1101 	}
1102 
1103 	driver_data = (struct driver_data *) &d[3];
1104 	driver_data->packet = packet;
1105 	packet->driver_data = driver_data;
1106 
1107 	if (packet->payload_length > 0) {
1108 		payload_bus =
1109 			dma_map_single(ohci->card.device, packet->payload,
1110 				       packet->payload_length, DMA_TO_DEVICE);
1111 		if (dma_mapping_error(ohci->card.device, payload_bus)) {
1112 			packet->ack = RCODE_SEND_ERROR;
1113 			return -1;
1114 		}
1115 		packet->payload_bus	= payload_bus;
1116 		packet->payload_mapped	= true;
1117 
1118 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1119 		d[2].data_address = cpu_to_le32(payload_bus);
1120 		last = &d[2];
1121 		z = 3;
1122 	} else {
1123 		last = &d[0];
1124 		z = 2;
1125 	}
1126 
1127 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1128 				     DESCRIPTOR_IRQ_ALWAYS |
1129 				     DESCRIPTOR_BRANCH_ALWAYS);
1130 
1131 	/*
1132 	 * If the controller and packet generations don't match, we need to
1133 	 * bail out and try again.  If IntEvent.busReset is set, the AT context
1134 	 * is halted, so appending to the context and trying to run it is
1135 	 * futile.  Most controllers do the right thing and just flush the AT
1136 	 * queue (per section 7.2.3.2 of the OHCI 1.1 specification), but
1137 	 * some controllers (like a JMicron JMB381 PCI-e) misbehave and wind
1138 	 * up stalling out.  So we just bail out in software and try again
1139 	 * later, and everyone is happy.
1140 	 * FIXME: Document how the locking works.
1141 	 */
1142 	if (ohci->generation != packet->generation ||
1143 	    reg_read(ohci, OHCI1394_IntEventSet) & OHCI1394_busReset) {
1144 		if (packet->payload_mapped)
1145 			dma_unmap_single(ohci->card.device, payload_bus,
1146 					 packet->payload_length, DMA_TO_DEVICE);
1147 		packet->ack = RCODE_GENERATION;
1148 		return -1;
1149 	}
1150 
1151 	context_append(ctx, d, z, 4 - z);
1152 
1153 	/* If the context isn't already running, start it up. */
1154 	reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1155 	if ((reg & CONTEXT_RUN) == 0)
1156 		context_run(ctx, 0);
1157 
1158 	return 0;
1159 }
1160 
1161 static int handle_at_packet(struct context *context,
1162 			    struct descriptor *d,
1163 			    struct descriptor *last)
1164 {
1165 	struct driver_data *driver_data;
1166 	struct fw_packet *packet;
1167 	struct fw_ohci *ohci = context->ohci;
1168 	int evt;
1169 
1170 	if (last->transfer_status == 0)
1171 		/* This descriptor isn't done yet, stop iteration. */
1172 		return 0;
1173 
1174 	driver_data = (struct driver_data *) &d[3];
1175 	packet = driver_data->packet;
1176 	if (packet == NULL)
1177 		/* This packet was cancelled, just continue. */
1178 		return 1;
1179 
1180 	if (packet->payload_mapped)
1181 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1182 				 packet->payload_length, DMA_TO_DEVICE);
1183 
1184 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1185 	packet->timestamp = le16_to_cpu(last->res_count);
1186 
1187 	log_ar_at_event('T', packet->speed, packet->header, evt);
1188 
1189 	switch (evt) {
1190 	case OHCI1394_evt_timeout:
1191 		/* Async response transmit timed out. */
1192 		packet->ack = RCODE_CANCELLED;
1193 		break;
1194 
1195 	case OHCI1394_evt_flushed:
1196 		/*
1197 		 * The packet was flushed should give same error as
1198 		 * when we try to use a stale generation count.
1199 		 */
1200 		packet->ack = RCODE_GENERATION;
1201 		break;
1202 
1203 	case OHCI1394_evt_missing_ack:
1204 		/*
1205 		 * Using a valid (current) generation count, but the
1206 		 * node is not on the bus or not sending acks.
1207 		 */
1208 		packet->ack = RCODE_NO_ACK;
1209 		break;
1210 
1211 	case ACK_COMPLETE + 0x10:
1212 	case ACK_PENDING + 0x10:
1213 	case ACK_BUSY_X + 0x10:
1214 	case ACK_BUSY_A + 0x10:
1215 	case ACK_BUSY_B + 0x10:
1216 	case ACK_DATA_ERROR + 0x10:
1217 	case ACK_TYPE_ERROR + 0x10:
1218 		packet->ack = evt - 0x10;
1219 		break;
1220 
1221 	default:
1222 		packet->ack = RCODE_SEND_ERROR;
1223 		break;
1224 	}
1225 
1226 	packet->callback(packet, &ohci->card, packet->ack);
1227 
1228 	return 1;
1229 }
1230 
1231 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1232 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1233 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1234 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1235 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1236 
1237 static void handle_local_rom(struct fw_ohci *ohci,
1238 			     struct fw_packet *packet, u32 csr)
1239 {
1240 	struct fw_packet response;
1241 	int tcode, length, i;
1242 
1243 	tcode = HEADER_GET_TCODE(packet->header[0]);
1244 	if (TCODE_IS_BLOCK_PACKET(tcode))
1245 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1246 	else
1247 		length = 4;
1248 
1249 	i = csr - CSR_CONFIG_ROM;
1250 	if (i + length > CONFIG_ROM_SIZE) {
1251 		fw_fill_response(&response, packet->header,
1252 				 RCODE_ADDRESS_ERROR, NULL, 0);
1253 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1254 		fw_fill_response(&response, packet->header,
1255 				 RCODE_TYPE_ERROR, NULL, 0);
1256 	} else {
1257 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1258 				 (void *) ohci->config_rom + i, length);
1259 	}
1260 
1261 	fw_core_handle_response(&ohci->card, &response);
1262 }
1263 
1264 static void handle_local_lock(struct fw_ohci *ohci,
1265 			      struct fw_packet *packet, u32 csr)
1266 {
1267 	struct fw_packet response;
1268 	int tcode, length, ext_tcode, sel, try;
1269 	__be32 *payload, lock_old;
1270 	u32 lock_arg, lock_data;
1271 
1272 	tcode = HEADER_GET_TCODE(packet->header[0]);
1273 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1274 	payload = packet->payload;
1275 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1276 
1277 	if (tcode == TCODE_LOCK_REQUEST &&
1278 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1279 		lock_arg = be32_to_cpu(payload[0]);
1280 		lock_data = be32_to_cpu(payload[1]);
1281 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1282 		lock_arg = 0;
1283 		lock_data = 0;
1284 	} else {
1285 		fw_fill_response(&response, packet->header,
1286 				 RCODE_TYPE_ERROR, NULL, 0);
1287 		goto out;
1288 	}
1289 
1290 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1291 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1292 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1293 	reg_write(ohci, OHCI1394_CSRControl, sel);
1294 
1295 	for (try = 0; try < 20; try++)
1296 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1297 			lock_old = cpu_to_be32(reg_read(ohci,
1298 							OHCI1394_CSRData));
1299 			fw_fill_response(&response, packet->header,
1300 					 RCODE_COMPLETE,
1301 					 &lock_old, sizeof(lock_old));
1302 			goto out;
1303 		}
1304 
1305 	fw_error("swap not done (CSR lock timeout)\n");
1306 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1307 
1308  out:
1309 	fw_core_handle_response(&ohci->card, &response);
1310 }
1311 
1312 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1313 {
1314 	u64 offset, csr;
1315 
1316 	if (ctx == &ctx->ohci->at_request_ctx) {
1317 		packet->ack = ACK_PENDING;
1318 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1319 	}
1320 
1321 	offset =
1322 		((unsigned long long)
1323 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1324 		packet->header[2];
1325 	csr = offset - CSR_REGISTER_BASE;
1326 
1327 	/* Handle config rom reads. */
1328 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1329 		handle_local_rom(ctx->ohci, packet, csr);
1330 	else switch (csr) {
1331 	case CSR_BUS_MANAGER_ID:
1332 	case CSR_BANDWIDTH_AVAILABLE:
1333 	case CSR_CHANNELS_AVAILABLE_HI:
1334 	case CSR_CHANNELS_AVAILABLE_LO:
1335 		handle_local_lock(ctx->ohci, packet, csr);
1336 		break;
1337 	default:
1338 		if (ctx == &ctx->ohci->at_request_ctx)
1339 			fw_core_handle_request(&ctx->ohci->card, packet);
1340 		else
1341 			fw_core_handle_response(&ctx->ohci->card, packet);
1342 		break;
1343 	}
1344 
1345 	if (ctx == &ctx->ohci->at_response_ctx) {
1346 		packet->ack = ACK_COMPLETE;
1347 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1348 	}
1349 }
1350 
1351 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1352 {
1353 	unsigned long flags;
1354 	int ret;
1355 
1356 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1357 
1358 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1359 	    ctx->ohci->generation == packet->generation) {
1360 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1361 		handle_local_request(ctx, packet);
1362 		return;
1363 	}
1364 
1365 	ret = at_context_queue_packet(ctx, packet);
1366 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1367 
1368 	if (ret < 0)
1369 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1370 
1371 }
1372 
1373 static u32 cycle_timer_ticks(u32 cycle_timer)
1374 {
1375 	u32 ticks;
1376 
1377 	ticks = cycle_timer & 0xfff;
1378 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1379 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1380 
1381 	return ticks;
1382 }
1383 
1384 /*
1385  * Some controllers exhibit one or more of the following bugs when updating the
1386  * iso cycle timer register:
1387  *  - When the lowest six bits are wrapping around to zero, a read that happens
1388  *    at the same time will return garbage in the lowest ten bits.
1389  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1390  *    not incremented for about 60 ns.
1391  *  - Occasionally, the entire register reads zero.
1392  *
1393  * To catch these, we read the register three times and ensure that the
1394  * difference between each two consecutive reads is approximately the same, i.e.
1395  * less than twice the other.  Furthermore, any negative difference indicates an
1396  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1397  * execute, so we have enough precision to compute the ratio of the differences.)
1398  */
1399 static u32 get_cycle_time(struct fw_ohci *ohci)
1400 {
1401 	u32 c0, c1, c2;
1402 	u32 t0, t1, t2;
1403 	s32 diff01, diff12;
1404 	int i;
1405 
1406 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1407 
1408 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1409 		i = 0;
1410 		c1 = c2;
1411 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1412 		do {
1413 			c0 = c1;
1414 			c1 = c2;
1415 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1416 			t0 = cycle_timer_ticks(c0);
1417 			t1 = cycle_timer_ticks(c1);
1418 			t2 = cycle_timer_ticks(c2);
1419 			diff01 = t1 - t0;
1420 			diff12 = t2 - t1;
1421 		} while ((diff01 <= 0 || diff12 <= 0 ||
1422 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1423 			 && i++ < 20);
1424 	}
1425 
1426 	return c2;
1427 }
1428 
1429 /*
1430  * This function has to be called at least every 64 seconds.  The bus_time
1431  * field stores not only the upper 25 bits of the BUS_TIME register but also
1432  * the most significant bit of the cycle timer in bit 6 so that we can detect
1433  * changes in this bit.
1434  */
1435 static u32 update_bus_time(struct fw_ohci *ohci)
1436 {
1437 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1438 
1439 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1440 		ohci->bus_time += 0x40;
1441 
1442 	return ohci->bus_time | cycle_time_seconds;
1443 }
1444 
1445 static void bus_reset_tasklet(unsigned long data)
1446 {
1447 	struct fw_ohci *ohci = (struct fw_ohci *)data;
1448 	int self_id_count, i, j, reg;
1449 	int generation, new_generation;
1450 	unsigned long flags;
1451 	void *free_rom = NULL;
1452 	dma_addr_t free_rom_bus = 0;
1453 	bool is_new_root;
1454 
1455 	reg = reg_read(ohci, OHCI1394_NodeID);
1456 	if (!(reg & OHCI1394_NodeID_idValid)) {
1457 		fw_notify("node ID not valid, new bus reset in progress\n");
1458 		return;
1459 	}
1460 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1461 		fw_notify("malconfigured bus\n");
1462 		return;
1463 	}
1464 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1465 			       OHCI1394_NodeID_nodeNumber);
1466 
1467 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1468 	if (!(ohci->is_root && is_new_root))
1469 		reg_write(ohci, OHCI1394_LinkControlSet,
1470 			  OHCI1394_LinkControl_cycleMaster);
1471 	ohci->is_root = is_new_root;
1472 
1473 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1474 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1475 		fw_notify("inconsistent self IDs\n");
1476 		return;
1477 	}
1478 	/*
1479 	 * The count in the SelfIDCount register is the number of
1480 	 * bytes in the self ID receive buffer.  Since we also receive
1481 	 * the inverted quadlets and a header quadlet, we shift one
1482 	 * bit extra to get the actual number of self IDs.
1483 	 */
1484 	self_id_count = (reg >> 3) & 0xff;
1485 	if (self_id_count == 0 || self_id_count > 252) {
1486 		fw_notify("inconsistent self IDs\n");
1487 		return;
1488 	}
1489 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1490 	rmb();
1491 
1492 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1493 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1494 			fw_notify("inconsistent self IDs\n");
1495 			return;
1496 		}
1497 		ohci->self_id_buffer[j] =
1498 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1499 	}
1500 	rmb();
1501 
1502 	/*
1503 	 * Check the consistency of the self IDs we just read.  The
1504 	 * problem we face is that a new bus reset can start while we
1505 	 * read out the self IDs from the DMA buffer. If this happens,
1506 	 * the DMA buffer will be overwritten with new self IDs and we
1507 	 * will read out inconsistent data.  The OHCI specification
1508 	 * (section 11.2) recommends a technique similar to
1509 	 * linux/seqlock.h, where we remember the generation of the
1510 	 * self IDs in the buffer before reading them out and compare
1511 	 * it to the current generation after reading them out.  If
1512 	 * the two generations match we know we have a consistent set
1513 	 * of self IDs.
1514 	 */
1515 
1516 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1517 	if (new_generation != generation) {
1518 		fw_notify("recursive bus reset detected, "
1519 			  "discarding self ids\n");
1520 		return;
1521 	}
1522 
1523 	/* FIXME: Document how the locking works. */
1524 	spin_lock_irqsave(&ohci->lock, flags);
1525 
1526 	ohci->generation = generation;
1527 	context_stop(&ohci->at_request_ctx);
1528 	context_stop(&ohci->at_response_ctx);
1529 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1530 
1531 	if (ohci->quirks & QUIRK_RESET_PACKET)
1532 		ohci->request_generation = generation;
1533 
1534 	/*
1535 	 * This next bit is unrelated to the AT context stuff but we
1536 	 * have to do it under the spinlock also.  If a new config rom
1537 	 * was set up before this reset, the old one is now no longer
1538 	 * in use and we can free it. Update the config rom pointers
1539 	 * to point to the current config rom and clear the
1540 	 * next_config_rom pointer so a new update can take place.
1541 	 */
1542 
1543 	if (ohci->next_config_rom != NULL) {
1544 		if (ohci->next_config_rom != ohci->config_rom) {
1545 			free_rom      = ohci->config_rom;
1546 			free_rom_bus  = ohci->config_rom_bus;
1547 		}
1548 		ohci->config_rom      = ohci->next_config_rom;
1549 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1550 		ohci->next_config_rom = NULL;
1551 
1552 		/*
1553 		 * Restore config_rom image and manually update
1554 		 * config_rom registers.  Writing the header quadlet
1555 		 * will indicate that the config rom is ready, so we
1556 		 * do that last.
1557 		 */
1558 		reg_write(ohci, OHCI1394_BusOptions,
1559 			  be32_to_cpu(ohci->config_rom[2]));
1560 		ohci->config_rom[0] = ohci->next_header;
1561 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1562 			  be32_to_cpu(ohci->next_header));
1563 	}
1564 
1565 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1566 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1567 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1568 #endif
1569 
1570 	spin_unlock_irqrestore(&ohci->lock, flags);
1571 
1572 	if (free_rom)
1573 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1574 				  free_rom, free_rom_bus);
1575 
1576 	log_selfids(ohci->node_id, generation,
1577 		    self_id_count, ohci->self_id_buffer);
1578 
1579 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1580 				 self_id_count, ohci->self_id_buffer,
1581 				 ohci->csr_state_setclear_abdicate);
1582 	ohci->csr_state_setclear_abdicate = false;
1583 }
1584 
1585 static irqreturn_t irq_handler(int irq, void *data)
1586 {
1587 	struct fw_ohci *ohci = data;
1588 	u32 event, iso_event;
1589 	int i;
1590 
1591 	event = reg_read(ohci, OHCI1394_IntEventClear);
1592 
1593 	if (!event || !~event)
1594 		return IRQ_NONE;
1595 
1596 	/* busReset must not be cleared yet, see OHCI 1.1 clause 7.2.3.2 */
1597 	reg_write(ohci, OHCI1394_IntEventClear, event & ~OHCI1394_busReset);
1598 	log_irqs(event);
1599 
1600 	if (event & OHCI1394_selfIDComplete)
1601 		tasklet_schedule(&ohci->bus_reset_tasklet);
1602 
1603 	if (event & OHCI1394_RQPkt)
1604 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1605 
1606 	if (event & OHCI1394_RSPkt)
1607 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1608 
1609 	if (event & OHCI1394_reqTxComplete)
1610 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
1611 
1612 	if (event & OHCI1394_respTxComplete)
1613 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
1614 
1615 	iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1616 	reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1617 
1618 	while (iso_event) {
1619 		i = ffs(iso_event) - 1;
1620 		tasklet_schedule(&ohci->ir_context_list[i].context.tasklet);
1621 		iso_event &= ~(1 << i);
1622 	}
1623 
1624 	iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1625 	reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1626 
1627 	while (iso_event) {
1628 		i = ffs(iso_event) - 1;
1629 		tasklet_schedule(&ohci->it_context_list[i].context.tasklet);
1630 		iso_event &= ~(1 << i);
1631 	}
1632 
1633 	if (unlikely(event & OHCI1394_regAccessFail))
1634 		fw_error("Register access failure - "
1635 			 "please notify linux1394-devel@lists.sf.net\n");
1636 
1637 	if (unlikely(event & OHCI1394_postedWriteErr))
1638 		fw_error("PCI posted write error\n");
1639 
1640 	if (unlikely(event & OHCI1394_cycleTooLong)) {
1641 		if (printk_ratelimit())
1642 			fw_notify("isochronous cycle too long\n");
1643 		reg_write(ohci, OHCI1394_LinkControlSet,
1644 			  OHCI1394_LinkControl_cycleMaster);
1645 	}
1646 
1647 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
1648 		/*
1649 		 * We need to clear this event bit in order to make
1650 		 * cycleMatch isochronous I/O work.  In theory we should
1651 		 * stop active cycleMatch iso contexts now and restart
1652 		 * them at least two cycles later.  (FIXME?)
1653 		 */
1654 		if (printk_ratelimit())
1655 			fw_notify("isochronous cycle inconsistent\n");
1656 	}
1657 
1658 	if (event & OHCI1394_cycle64Seconds) {
1659 		spin_lock(&ohci->lock);
1660 		update_bus_time(ohci);
1661 		spin_unlock(&ohci->lock);
1662 	}
1663 
1664 	return IRQ_HANDLED;
1665 }
1666 
1667 static int software_reset(struct fw_ohci *ohci)
1668 {
1669 	int i;
1670 
1671 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1672 
1673 	for (i = 0; i < OHCI_LOOP_COUNT; i++) {
1674 		if ((reg_read(ohci, OHCI1394_HCControlSet) &
1675 		     OHCI1394_HCControl_softReset) == 0)
1676 			return 0;
1677 		msleep(1);
1678 	}
1679 
1680 	return -EBUSY;
1681 }
1682 
1683 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
1684 {
1685 	size_t size = length * 4;
1686 
1687 	memcpy(dest, src, size);
1688 	if (size < CONFIG_ROM_SIZE)
1689 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
1690 }
1691 
1692 static int configure_1394a_enhancements(struct fw_ohci *ohci)
1693 {
1694 	bool enable_1394a;
1695 	int ret, clear, set, offset;
1696 
1697 	/* Check if the driver should configure link and PHY. */
1698 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
1699 	      OHCI1394_HCControl_programPhyEnable))
1700 		return 0;
1701 
1702 	/* Paranoia: check whether the PHY supports 1394a, too. */
1703 	enable_1394a = false;
1704 	ret = read_phy_reg(ohci, 2);
1705 	if (ret < 0)
1706 		return ret;
1707 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
1708 		ret = read_paged_phy_reg(ohci, 1, 8);
1709 		if (ret < 0)
1710 			return ret;
1711 		if (ret >= 1)
1712 			enable_1394a = true;
1713 	}
1714 
1715 	if (ohci->quirks & QUIRK_NO_1394A)
1716 		enable_1394a = false;
1717 
1718 	/* Configure PHY and link consistently. */
1719 	if (enable_1394a) {
1720 		clear = 0;
1721 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
1722 	} else {
1723 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
1724 		set = 0;
1725 	}
1726 	ret = update_phy_reg(ohci, 5, clear, set);
1727 	if (ret < 0)
1728 		return ret;
1729 
1730 	if (enable_1394a)
1731 		offset = OHCI1394_HCControlSet;
1732 	else
1733 		offset = OHCI1394_HCControlClear;
1734 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
1735 
1736 	/* Clean up: configuration has been taken care of. */
1737 	reg_write(ohci, OHCI1394_HCControlClear,
1738 		  OHCI1394_HCControl_programPhyEnable);
1739 
1740 	return 0;
1741 }
1742 
1743 static int ohci_enable(struct fw_card *card,
1744 		       const __be32 *config_rom, size_t length)
1745 {
1746 	struct fw_ohci *ohci = fw_ohci(card);
1747 	struct pci_dev *dev = to_pci_dev(card->device);
1748 	u32 lps, seconds, version, irqs;
1749 	int i, ret;
1750 
1751 	if (software_reset(ohci)) {
1752 		fw_error("Failed to reset ohci card.\n");
1753 		return -EBUSY;
1754 	}
1755 
1756 	/*
1757 	 * Now enable LPS, which we need in order to start accessing
1758 	 * most of the registers.  In fact, on some cards (ALI M5251),
1759 	 * accessing registers in the SClk domain without LPS enabled
1760 	 * will lock up the machine.  Wait 50msec to make sure we have
1761 	 * full link enabled.  However, with some cards (well, at least
1762 	 * a JMicron PCIe card), we have to try again sometimes.
1763 	 */
1764 	reg_write(ohci, OHCI1394_HCControlSet,
1765 		  OHCI1394_HCControl_LPS |
1766 		  OHCI1394_HCControl_postedWriteEnable);
1767 	flush_writes(ohci);
1768 
1769 	for (lps = 0, i = 0; !lps && i < 3; i++) {
1770 		msleep(50);
1771 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
1772 		      OHCI1394_HCControl_LPS;
1773 	}
1774 
1775 	if (!lps) {
1776 		fw_error("Failed to set Link Power Status\n");
1777 		return -EIO;
1778 	}
1779 
1780 	reg_write(ohci, OHCI1394_HCControlClear,
1781 		  OHCI1394_HCControl_noByteSwapData);
1782 
1783 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
1784 	reg_write(ohci, OHCI1394_LinkControlSet,
1785 		  OHCI1394_LinkControl_rcvSelfID |
1786 		  OHCI1394_LinkControl_rcvPhyPkt |
1787 		  OHCI1394_LinkControl_cycleTimerEnable |
1788 		  OHCI1394_LinkControl_cycleMaster);
1789 
1790 	reg_write(ohci, OHCI1394_ATRetries,
1791 		  OHCI1394_MAX_AT_REQ_RETRIES |
1792 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
1793 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
1794 		  (200 << 16));
1795 
1796 	seconds = lower_32_bits(get_seconds());
1797 	reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
1798 	ohci->bus_time = seconds & ~0x3f;
1799 
1800 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
1801 	if (version >= OHCI_VERSION_1_1) {
1802 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
1803 			  0xfffffffe);
1804 		card->broadcast_channel_auto_allocated = true;
1805 	}
1806 
1807 	/* Get implemented bits of the priority arbitration request counter. */
1808 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
1809 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
1810 	reg_write(ohci, OHCI1394_FairnessControl, 0);
1811 	card->priority_budget_implemented = ohci->pri_req_max != 0;
1812 
1813 	ar_context_run(&ohci->ar_request_ctx);
1814 	ar_context_run(&ohci->ar_response_ctx);
1815 
1816 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
1817 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
1818 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
1819 
1820 	ret = configure_1394a_enhancements(ohci);
1821 	if (ret < 0)
1822 		return ret;
1823 
1824 	/* Activate link_on bit and contender bit in our self ID packets.*/
1825 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
1826 	if (ret < 0)
1827 		return ret;
1828 
1829 	/*
1830 	 * When the link is not yet enabled, the atomic config rom
1831 	 * update mechanism described below in ohci_set_config_rom()
1832 	 * is not active.  We have to update ConfigRomHeader and
1833 	 * BusOptions manually, and the write to ConfigROMmap takes
1834 	 * effect immediately.  We tie this to the enabling of the
1835 	 * link, so we have a valid config rom before enabling - the
1836 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
1837 	 * values before enabling.
1838 	 *
1839 	 * However, when the ConfigROMmap is written, some controllers
1840 	 * always read back quadlets 0 and 2 from the config rom to
1841 	 * the ConfigRomHeader and BusOptions registers on bus reset.
1842 	 * They shouldn't do that in this initial case where the link
1843 	 * isn't enabled.  This means we have to use the same
1844 	 * workaround here, setting the bus header to 0 and then write
1845 	 * the right values in the bus reset tasklet.
1846 	 */
1847 
1848 	if (config_rom) {
1849 		ohci->next_config_rom =
1850 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1851 					   &ohci->next_config_rom_bus,
1852 					   GFP_KERNEL);
1853 		if (ohci->next_config_rom == NULL)
1854 			return -ENOMEM;
1855 
1856 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1857 	} else {
1858 		/*
1859 		 * In the suspend case, config_rom is NULL, which
1860 		 * means that we just reuse the old config rom.
1861 		 */
1862 		ohci->next_config_rom = ohci->config_rom;
1863 		ohci->next_config_rom_bus = ohci->config_rom_bus;
1864 	}
1865 
1866 	ohci->next_header = ohci->next_config_rom[0];
1867 	ohci->next_config_rom[0] = 0;
1868 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
1869 	reg_write(ohci, OHCI1394_BusOptions,
1870 		  be32_to_cpu(ohci->next_config_rom[2]));
1871 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
1872 
1873 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
1874 
1875 	if (!(ohci->quirks & QUIRK_NO_MSI))
1876 		pci_enable_msi(dev);
1877 	if (request_irq(dev->irq, irq_handler,
1878 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
1879 			ohci_driver_name, ohci)) {
1880 		fw_error("Failed to allocate interrupt %d.\n", dev->irq);
1881 		pci_disable_msi(dev);
1882 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1883 				  ohci->config_rom, ohci->config_rom_bus);
1884 		return -EIO;
1885 	}
1886 
1887 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
1888 		OHCI1394_RQPkt | OHCI1394_RSPkt |
1889 		OHCI1394_isochTx | OHCI1394_isochRx |
1890 		OHCI1394_postedWriteErr |
1891 		OHCI1394_selfIDComplete |
1892 		OHCI1394_regAccessFail |
1893 		OHCI1394_cycle64Seconds |
1894 		OHCI1394_cycleInconsistent | OHCI1394_cycleTooLong |
1895 		OHCI1394_masterIntEnable;
1896 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
1897 		irqs |= OHCI1394_busReset;
1898 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
1899 
1900 	reg_write(ohci, OHCI1394_HCControlSet,
1901 		  OHCI1394_HCControl_linkEnable |
1902 		  OHCI1394_HCControl_BIBimageValid);
1903 	flush_writes(ohci);
1904 
1905 	/* We are ready to go, reset bus to finish initialization. */
1906 	fw_schedule_bus_reset(&ohci->card, false, true);
1907 
1908 	return 0;
1909 }
1910 
1911 static int ohci_set_config_rom(struct fw_card *card,
1912 			       const __be32 *config_rom, size_t length)
1913 {
1914 	struct fw_ohci *ohci;
1915 	unsigned long flags;
1916 	int ret = -EBUSY;
1917 	__be32 *next_config_rom;
1918 	dma_addr_t uninitialized_var(next_config_rom_bus);
1919 
1920 	ohci = fw_ohci(card);
1921 
1922 	/*
1923 	 * When the OHCI controller is enabled, the config rom update
1924 	 * mechanism is a bit tricky, but easy enough to use.  See
1925 	 * section 5.5.6 in the OHCI specification.
1926 	 *
1927 	 * The OHCI controller caches the new config rom address in a
1928 	 * shadow register (ConfigROMmapNext) and needs a bus reset
1929 	 * for the changes to take place.  When the bus reset is
1930 	 * detected, the controller loads the new values for the
1931 	 * ConfigRomHeader and BusOptions registers from the specified
1932 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
1933 	 * shadow register. All automatically and atomically.
1934 	 *
1935 	 * Now, there's a twist to this story.  The automatic load of
1936 	 * ConfigRomHeader and BusOptions doesn't honor the
1937 	 * noByteSwapData bit, so with a be32 config rom, the
1938 	 * controller will load be32 values in to these registers
1939 	 * during the atomic update, even on litte endian
1940 	 * architectures.  The workaround we use is to put a 0 in the
1941 	 * header quadlet; 0 is endian agnostic and means that the
1942 	 * config rom isn't ready yet.  In the bus reset tasklet we
1943 	 * then set up the real values for the two registers.
1944 	 *
1945 	 * We use ohci->lock to avoid racing with the code that sets
1946 	 * ohci->next_config_rom to NULL (see bus_reset_tasklet).
1947 	 */
1948 
1949 	next_config_rom =
1950 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1951 				   &next_config_rom_bus, GFP_KERNEL);
1952 	if (next_config_rom == NULL)
1953 		return -ENOMEM;
1954 
1955 	spin_lock_irqsave(&ohci->lock, flags);
1956 
1957 	if (ohci->next_config_rom == NULL) {
1958 		ohci->next_config_rom = next_config_rom;
1959 		ohci->next_config_rom_bus = next_config_rom_bus;
1960 
1961 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1962 
1963 		ohci->next_header = config_rom[0];
1964 		ohci->next_config_rom[0] = 0;
1965 
1966 		reg_write(ohci, OHCI1394_ConfigROMmap,
1967 			  ohci->next_config_rom_bus);
1968 		ret = 0;
1969 	}
1970 
1971 	spin_unlock_irqrestore(&ohci->lock, flags);
1972 
1973 	/*
1974 	 * Now initiate a bus reset to have the changes take
1975 	 * effect. We clean up the old config rom memory and DMA
1976 	 * mappings in the bus reset tasklet, since the OHCI
1977 	 * controller could need to access it before the bus reset
1978 	 * takes effect.
1979 	 */
1980 	if (ret == 0)
1981 		fw_schedule_bus_reset(&ohci->card, true, true);
1982 	else
1983 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1984 				  next_config_rom, next_config_rom_bus);
1985 
1986 	return ret;
1987 }
1988 
1989 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
1990 {
1991 	struct fw_ohci *ohci = fw_ohci(card);
1992 
1993 	at_context_transmit(&ohci->at_request_ctx, packet);
1994 }
1995 
1996 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
1997 {
1998 	struct fw_ohci *ohci = fw_ohci(card);
1999 
2000 	at_context_transmit(&ohci->at_response_ctx, packet);
2001 }
2002 
2003 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2004 {
2005 	struct fw_ohci *ohci = fw_ohci(card);
2006 	struct context *ctx = &ohci->at_request_ctx;
2007 	struct driver_data *driver_data = packet->driver_data;
2008 	int ret = -ENOENT;
2009 
2010 	tasklet_disable(&ctx->tasklet);
2011 
2012 	if (packet->ack != 0)
2013 		goto out;
2014 
2015 	if (packet->payload_mapped)
2016 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2017 				 packet->payload_length, DMA_TO_DEVICE);
2018 
2019 	log_ar_at_event('T', packet->speed, packet->header, 0x20);
2020 	driver_data->packet = NULL;
2021 	packet->ack = RCODE_CANCELLED;
2022 	packet->callback(packet, &ohci->card, packet->ack);
2023 	ret = 0;
2024  out:
2025 	tasklet_enable(&ctx->tasklet);
2026 
2027 	return ret;
2028 }
2029 
2030 static int ohci_enable_phys_dma(struct fw_card *card,
2031 				int node_id, int generation)
2032 {
2033 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2034 	return 0;
2035 #else
2036 	struct fw_ohci *ohci = fw_ohci(card);
2037 	unsigned long flags;
2038 	int n, ret = 0;
2039 
2040 	/*
2041 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2042 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2043 	 */
2044 
2045 	spin_lock_irqsave(&ohci->lock, flags);
2046 
2047 	if (ohci->generation != generation) {
2048 		ret = -ESTALE;
2049 		goto out;
2050 	}
2051 
2052 	/*
2053 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2054 	 * enabled for _all_ nodes on remote buses.
2055 	 */
2056 
2057 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2058 	if (n < 32)
2059 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2060 	else
2061 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2062 
2063 	flush_writes(ohci);
2064  out:
2065 	spin_unlock_irqrestore(&ohci->lock, flags);
2066 
2067 	return ret;
2068 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2069 }
2070 
2071 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2072 {
2073 	struct fw_ohci *ohci = fw_ohci(card);
2074 	unsigned long flags;
2075 	u32 value;
2076 
2077 	switch (csr_offset) {
2078 	case CSR_STATE_CLEAR:
2079 	case CSR_STATE_SET:
2080 		if (ohci->is_root &&
2081 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2082 		     OHCI1394_LinkControl_cycleMaster))
2083 			value = CSR_STATE_BIT_CMSTR;
2084 		else
2085 			value = 0;
2086 		if (ohci->csr_state_setclear_abdicate)
2087 			value |= CSR_STATE_BIT_ABDICATE;
2088 
2089 		return value;
2090 
2091 	case CSR_NODE_IDS:
2092 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2093 
2094 	case CSR_CYCLE_TIME:
2095 		return get_cycle_time(ohci);
2096 
2097 	case CSR_BUS_TIME:
2098 		/*
2099 		 * We might be called just after the cycle timer has wrapped
2100 		 * around but just before the cycle64Seconds handler, so we
2101 		 * better check here, too, if the bus time needs to be updated.
2102 		 */
2103 		spin_lock_irqsave(&ohci->lock, flags);
2104 		value = update_bus_time(ohci);
2105 		spin_unlock_irqrestore(&ohci->lock, flags);
2106 		return value;
2107 
2108 	case CSR_BUSY_TIMEOUT:
2109 		value = reg_read(ohci, OHCI1394_ATRetries);
2110 		return (value >> 4) & 0x0ffff00f;
2111 
2112 	case CSR_PRIORITY_BUDGET:
2113 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2114 			(ohci->pri_req_max << 8);
2115 
2116 	default:
2117 		WARN_ON(1);
2118 		return 0;
2119 	}
2120 }
2121 
2122 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2123 {
2124 	struct fw_ohci *ohci = fw_ohci(card);
2125 	unsigned long flags;
2126 
2127 	switch (csr_offset) {
2128 	case CSR_STATE_CLEAR:
2129 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2130 			reg_write(ohci, OHCI1394_LinkControlClear,
2131 				  OHCI1394_LinkControl_cycleMaster);
2132 			flush_writes(ohci);
2133 		}
2134 		if (value & CSR_STATE_BIT_ABDICATE)
2135 			ohci->csr_state_setclear_abdicate = false;
2136 		break;
2137 
2138 	case CSR_STATE_SET:
2139 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2140 			reg_write(ohci, OHCI1394_LinkControlSet,
2141 				  OHCI1394_LinkControl_cycleMaster);
2142 			flush_writes(ohci);
2143 		}
2144 		if (value & CSR_STATE_BIT_ABDICATE)
2145 			ohci->csr_state_setclear_abdicate = true;
2146 		break;
2147 
2148 	case CSR_NODE_IDS:
2149 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2150 		flush_writes(ohci);
2151 		break;
2152 
2153 	case CSR_CYCLE_TIME:
2154 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2155 		reg_write(ohci, OHCI1394_IntEventSet,
2156 			  OHCI1394_cycleInconsistent);
2157 		flush_writes(ohci);
2158 		break;
2159 
2160 	case CSR_BUS_TIME:
2161 		spin_lock_irqsave(&ohci->lock, flags);
2162 		ohci->bus_time = (ohci->bus_time & 0x7f) | (value & ~0x7f);
2163 		spin_unlock_irqrestore(&ohci->lock, flags);
2164 		break;
2165 
2166 	case CSR_BUSY_TIMEOUT:
2167 		value = (value & 0xf) | ((value & 0xf) << 4) |
2168 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2169 		reg_write(ohci, OHCI1394_ATRetries, value);
2170 		flush_writes(ohci);
2171 		break;
2172 
2173 	case CSR_PRIORITY_BUDGET:
2174 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2175 		flush_writes(ohci);
2176 		break;
2177 
2178 	default:
2179 		WARN_ON(1);
2180 		break;
2181 	}
2182 }
2183 
2184 static void copy_iso_headers(struct iso_context *ctx, void *p)
2185 {
2186 	int i = ctx->header_length;
2187 
2188 	if (i + ctx->base.header_size > PAGE_SIZE)
2189 		return;
2190 
2191 	/*
2192 	 * The iso header is byteswapped to little endian by
2193 	 * the controller, but the remaining header quadlets
2194 	 * are big endian.  We want to present all the headers
2195 	 * as big endian, so we have to swap the first quadlet.
2196 	 */
2197 	if (ctx->base.header_size > 0)
2198 		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
2199 	if (ctx->base.header_size > 4)
2200 		*(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
2201 	if (ctx->base.header_size > 8)
2202 		memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
2203 	ctx->header_length += ctx->base.header_size;
2204 }
2205 
2206 static int handle_ir_packet_per_buffer(struct context *context,
2207 				       struct descriptor *d,
2208 				       struct descriptor *last)
2209 {
2210 	struct iso_context *ctx =
2211 		container_of(context, struct iso_context, context);
2212 	struct descriptor *pd;
2213 	__le32 *ir_header;
2214 	void *p;
2215 
2216 	for (pd = d; pd <= last; pd++)
2217 		if (pd->transfer_status)
2218 			break;
2219 	if (pd > last)
2220 		/* Descriptor(s) not done yet, stop iteration */
2221 		return 0;
2222 
2223 	p = last + 1;
2224 	copy_iso_headers(ctx, p);
2225 
2226 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2227 		ir_header = (__le32 *) p;
2228 		ctx->base.callback.sc(&ctx->base,
2229 				      le32_to_cpu(ir_header[0]) & 0xffff,
2230 				      ctx->header_length, ctx->header,
2231 				      ctx->base.callback_data);
2232 		ctx->header_length = 0;
2233 	}
2234 
2235 	return 1;
2236 }
2237 
2238 /* d == last because each descriptor block is only a single descriptor. */
2239 static int handle_ir_buffer_fill(struct context *context,
2240 				 struct descriptor *d,
2241 				 struct descriptor *last)
2242 {
2243 	struct iso_context *ctx =
2244 		container_of(context, struct iso_context, context);
2245 
2246 	if (!last->transfer_status)
2247 		/* Descriptor(s) not done yet, stop iteration */
2248 		return 0;
2249 
2250 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS)
2251 		ctx->base.callback.mc(&ctx->base,
2252 				      le32_to_cpu(last->data_address) +
2253 				      le16_to_cpu(last->req_count) -
2254 				      le16_to_cpu(last->res_count),
2255 				      ctx->base.callback_data);
2256 
2257 	return 1;
2258 }
2259 
2260 static int handle_it_packet(struct context *context,
2261 			    struct descriptor *d,
2262 			    struct descriptor *last)
2263 {
2264 	struct iso_context *ctx =
2265 		container_of(context, struct iso_context, context);
2266 	int i;
2267 	struct descriptor *pd;
2268 
2269 	for (pd = d; pd <= last; pd++)
2270 		if (pd->transfer_status)
2271 			break;
2272 	if (pd > last)
2273 		/* Descriptor(s) not done yet, stop iteration */
2274 		return 0;
2275 
2276 	i = ctx->header_length;
2277 	if (i + 4 < PAGE_SIZE) {
2278 		/* Present this value as big-endian to match the receive code */
2279 		*(__be32 *)(ctx->header + i) = cpu_to_be32(
2280 				((u32)le16_to_cpu(pd->transfer_status) << 16) |
2281 				le16_to_cpu(pd->res_count));
2282 		ctx->header_length += 4;
2283 	}
2284 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2285 		ctx->base.callback.sc(&ctx->base, le16_to_cpu(last->res_count),
2286 				      ctx->header_length, ctx->header,
2287 				      ctx->base.callback_data);
2288 		ctx->header_length = 0;
2289 	}
2290 	return 1;
2291 }
2292 
2293 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2294 {
2295 	u32 hi = channels >> 32, lo = channels;
2296 
2297 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2298 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2299 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2300 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2301 	mmiowb();
2302 	ohci->mc_channels = channels;
2303 }
2304 
2305 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2306 				int type, int channel, size_t header_size)
2307 {
2308 	struct fw_ohci *ohci = fw_ohci(card);
2309 	struct iso_context *uninitialized_var(ctx);
2310 	descriptor_callback_t uninitialized_var(callback);
2311 	u64 *uninitialized_var(channels);
2312 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2313 	unsigned long flags;
2314 	int index, ret = -EBUSY;
2315 
2316 	spin_lock_irqsave(&ohci->lock, flags);
2317 
2318 	switch (type) {
2319 	case FW_ISO_CONTEXT_TRANSMIT:
2320 		mask     = &ohci->it_context_mask;
2321 		callback = handle_it_packet;
2322 		index    = ffs(*mask) - 1;
2323 		if (index >= 0) {
2324 			*mask &= ~(1 << index);
2325 			regs = OHCI1394_IsoXmitContextBase(index);
2326 			ctx  = &ohci->it_context_list[index];
2327 		}
2328 		break;
2329 
2330 	case FW_ISO_CONTEXT_RECEIVE:
2331 		channels = &ohci->ir_context_channels;
2332 		mask     = &ohci->ir_context_mask;
2333 		callback = handle_ir_packet_per_buffer;
2334 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2335 		if (index >= 0) {
2336 			*channels &= ~(1ULL << channel);
2337 			*mask     &= ~(1 << index);
2338 			regs = OHCI1394_IsoRcvContextBase(index);
2339 			ctx  = &ohci->ir_context_list[index];
2340 		}
2341 		break;
2342 
2343 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2344 		mask     = &ohci->ir_context_mask;
2345 		callback = handle_ir_buffer_fill;
2346 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2347 		if (index >= 0) {
2348 			ohci->mc_allocated = true;
2349 			*mask &= ~(1 << index);
2350 			regs = OHCI1394_IsoRcvContextBase(index);
2351 			ctx  = &ohci->ir_context_list[index];
2352 		}
2353 		break;
2354 
2355 	default:
2356 		index = -1;
2357 		ret = -ENOSYS;
2358 	}
2359 
2360 	spin_unlock_irqrestore(&ohci->lock, flags);
2361 
2362 	if (index < 0)
2363 		return ERR_PTR(ret);
2364 
2365 	memset(ctx, 0, sizeof(*ctx));
2366 	ctx->header_length = 0;
2367 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2368 	if (ctx->header == NULL) {
2369 		ret = -ENOMEM;
2370 		goto out;
2371 	}
2372 	ret = context_init(&ctx->context, ohci, regs, callback);
2373 	if (ret < 0)
2374 		goto out_with_header;
2375 
2376 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
2377 		set_multichannel_mask(ohci, 0);
2378 
2379 	return &ctx->base;
2380 
2381  out_with_header:
2382 	free_page((unsigned long)ctx->header);
2383  out:
2384 	spin_lock_irqsave(&ohci->lock, flags);
2385 
2386 	switch (type) {
2387 	case FW_ISO_CONTEXT_RECEIVE:
2388 		*channels |= 1ULL << channel;
2389 		break;
2390 
2391 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2392 		ohci->mc_allocated = false;
2393 		break;
2394 	}
2395 	*mask |= 1 << index;
2396 
2397 	spin_unlock_irqrestore(&ohci->lock, flags);
2398 
2399 	return ERR_PTR(ret);
2400 }
2401 
2402 static int ohci_start_iso(struct fw_iso_context *base,
2403 			  s32 cycle, u32 sync, u32 tags)
2404 {
2405 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2406 	struct fw_ohci *ohci = ctx->context.ohci;
2407 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2408 	int index;
2409 
2410 	switch (ctx->base.type) {
2411 	case FW_ISO_CONTEXT_TRANSMIT:
2412 		index = ctx - ohci->it_context_list;
2413 		match = 0;
2414 		if (cycle >= 0)
2415 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
2416 				(cycle & 0x7fff) << 16;
2417 
2418 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
2419 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
2420 		context_run(&ctx->context, match);
2421 		break;
2422 
2423 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2424 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
2425 		/* fall through */
2426 	case FW_ISO_CONTEXT_RECEIVE:
2427 		index = ctx - ohci->ir_context_list;
2428 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
2429 		if (cycle >= 0) {
2430 			match |= (cycle & 0x07fff) << 12;
2431 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
2432 		}
2433 
2434 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2435 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2436 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2437 		context_run(&ctx->context, control);
2438 		break;
2439 	}
2440 
2441 	return 0;
2442 }
2443 
2444 static int ohci_stop_iso(struct fw_iso_context *base)
2445 {
2446 	struct fw_ohci *ohci = fw_ohci(base->card);
2447 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2448 	int index;
2449 
2450 	switch (ctx->base.type) {
2451 	case FW_ISO_CONTEXT_TRANSMIT:
2452 		index = ctx - ohci->it_context_list;
2453 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2454 		break;
2455 
2456 	case FW_ISO_CONTEXT_RECEIVE:
2457 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2458 		index = ctx - ohci->ir_context_list;
2459 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2460 		break;
2461 	}
2462 	flush_writes(ohci);
2463 	context_stop(&ctx->context);
2464 
2465 	return 0;
2466 }
2467 
2468 static void ohci_free_iso_context(struct fw_iso_context *base)
2469 {
2470 	struct fw_ohci *ohci = fw_ohci(base->card);
2471 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2472 	unsigned long flags;
2473 	int index;
2474 
2475 	ohci_stop_iso(base);
2476 	context_release(&ctx->context);
2477 	free_page((unsigned long)ctx->header);
2478 
2479 	spin_lock_irqsave(&ohci->lock, flags);
2480 
2481 	switch (base->type) {
2482 	case FW_ISO_CONTEXT_TRANSMIT:
2483 		index = ctx - ohci->it_context_list;
2484 		ohci->it_context_mask |= 1 << index;
2485 		break;
2486 
2487 	case FW_ISO_CONTEXT_RECEIVE:
2488 		index = ctx - ohci->ir_context_list;
2489 		ohci->ir_context_mask |= 1 << index;
2490 		ohci->ir_context_channels |= 1ULL << base->channel;
2491 		break;
2492 
2493 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2494 		index = ctx - ohci->ir_context_list;
2495 		ohci->ir_context_mask |= 1 << index;
2496 		ohci->ir_context_channels |= ohci->mc_channels;
2497 		ohci->mc_channels = 0;
2498 		ohci->mc_allocated = false;
2499 		break;
2500 	}
2501 
2502 	spin_unlock_irqrestore(&ohci->lock, flags);
2503 }
2504 
2505 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
2506 {
2507 	struct fw_ohci *ohci = fw_ohci(base->card);
2508 	unsigned long flags;
2509 	int ret;
2510 
2511 	switch (base->type) {
2512 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2513 
2514 		spin_lock_irqsave(&ohci->lock, flags);
2515 
2516 		/* Don't allow multichannel to grab other contexts' channels. */
2517 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
2518 			*channels = ohci->ir_context_channels;
2519 			ret = -EBUSY;
2520 		} else {
2521 			set_multichannel_mask(ohci, *channels);
2522 			ret = 0;
2523 		}
2524 
2525 		spin_unlock_irqrestore(&ohci->lock, flags);
2526 
2527 		break;
2528 	default:
2529 		ret = -EINVAL;
2530 	}
2531 
2532 	return ret;
2533 }
2534 
2535 static int queue_iso_transmit(struct iso_context *ctx,
2536 			      struct fw_iso_packet *packet,
2537 			      struct fw_iso_buffer *buffer,
2538 			      unsigned long payload)
2539 {
2540 	struct descriptor *d, *last, *pd;
2541 	struct fw_iso_packet *p;
2542 	__le32 *header;
2543 	dma_addr_t d_bus, page_bus;
2544 	u32 z, header_z, payload_z, irq;
2545 	u32 payload_index, payload_end_index, next_page_index;
2546 	int page, end_page, i, length, offset;
2547 
2548 	p = packet;
2549 	payload_index = payload;
2550 
2551 	if (p->skip)
2552 		z = 1;
2553 	else
2554 		z = 2;
2555 	if (p->header_length > 0)
2556 		z++;
2557 
2558 	/* Determine the first page the payload isn't contained in. */
2559 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2560 	if (p->payload_length > 0)
2561 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
2562 	else
2563 		payload_z = 0;
2564 
2565 	z += payload_z;
2566 
2567 	/* Get header size in number of descriptors. */
2568 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2569 
2570 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2571 	if (d == NULL)
2572 		return -ENOMEM;
2573 
2574 	if (!p->skip) {
2575 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2576 		d[0].req_count = cpu_to_le16(8);
2577 		/*
2578 		 * Link the skip address to this descriptor itself.  This causes
2579 		 * a context to skip a cycle whenever lost cycles or FIFO
2580 		 * overruns occur, without dropping the data.  The application
2581 		 * should then decide whether this is an error condition or not.
2582 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
2583 		 */
2584 		d[0].branch_address = cpu_to_le32(d_bus | z);
2585 
2586 		header = (__le32 *) &d[1];
2587 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2588 					IT_HEADER_TAG(p->tag) |
2589 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2590 					IT_HEADER_CHANNEL(ctx->base.channel) |
2591 					IT_HEADER_SPEED(ctx->base.speed));
2592 		header[1] =
2593 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2594 							  p->payload_length));
2595 	}
2596 
2597 	if (p->header_length > 0) {
2598 		d[2].req_count    = cpu_to_le16(p->header_length);
2599 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2600 		memcpy(&d[z], p->header, p->header_length);
2601 	}
2602 
2603 	pd = d + z - payload_z;
2604 	payload_end_index = payload_index + p->payload_length;
2605 	for (i = 0; i < payload_z; i++) {
2606 		page               = payload_index >> PAGE_SHIFT;
2607 		offset             = payload_index & ~PAGE_MASK;
2608 		next_page_index    = (page + 1) << PAGE_SHIFT;
2609 		length             =
2610 			min(next_page_index, payload_end_index) - payload_index;
2611 		pd[i].req_count    = cpu_to_le16(length);
2612 
2613 		page_bus = page_private(buffer->pages[page]);
2614 		pd[i].data_address = cpu_to_le32(page_bus + offset);
2615 
2616 		payload_index += length;
2617 	}
2618 
2619 	if (p->interrupt)
2620 		irq = DESCRIPTOR_IRQ_ALWAYS;
2621 	else
2622 		irq = DESCRIPTOR_NO_IRQ;
2623 
2624 	last = z == 2 ? d : d + z - 1;
2625 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2626 				     DESCRIPTOR_STATUS |
2627 				     DESCRIPTOR_BRANCH_ALWAYS |
2628 				     irq);
2629 
2630 	context_append(&ctx->context, d, z, header_z);
2631 
2632 	return 0;
2633 }
2634 
2635 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
2636 				       struct fw_iso_packet *packet,
2637 				       struct fw_iso_buffer *buffer,
2638 				       unsigned long payload)
2639 {
2640 	struct descriptor *d, *pd;
2641 	dma_addr_t d_bus, page_bus;
2642 	u32 z, header_z, rest;
2643 	int i, j, length;
2644 	int page, offset, packet_count, header_size, payload_per_buffer;
2645 
2646 	/*
2647 	 * The OHCI controller puts the isochronous header and trailer in the
2648 	 * buffer, so we need at least 8 bytes.
2649 	 */
2650 	packet_count = packet->header_length / ctx->base.header_size;
2651 	header_size  = max(ctx->base.header_size, (size_t)8);
2652 
2653 	/* Get header size in number of descriptors. */
2654 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2655 	page     = payload >> PAGE_SHIFT;
2656 	offset   = payload & ~PAGE_MASK;
2657 	payload_per_buffer = packet->payload_length / packet_count;
2658 
2659 	for (i = 0; i < packet_count; i++) {
2660 		/* d points to the header descriptor */
2661 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
2662 		d = context_get_descriptors(&ctx->context,
2663 				z + header_z, &d_bus);
2664 		if (d == NULL)
2665 			return -ENOMEM;
2666 
2667 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
2668 					      DESCRIPTOR_INPUT_MORE);
2669 		if (packet->skip && i == 0)
2670 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2671 		d->req_count    = cpu_to_le16(header_size);
2672 		d->res_count    = d->req_count;
2673 		d->transfer_status = 0;
2674 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
2675 
2676 		rest = payload_per_buffer;
2677 		pd = d;
2678 		for (j = 1; j < z; j++) {
2679 			pd++;
2680 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2681 						  DESCRIPTOR_INPUT_MORE);
2682 
2683 			if (offset + rest < PAGE_SIZE)
2684 				length = rest;
2685 			else
2686 				length = PAGE_SIZE - offset;
2687 			pd->req_count = cpu_to_le16(length);
2688 			pd->res_count = pd->req_count;
2689 			pd->transfer_status = 0;
2690 
2691 			page_bus = page_private(buffer->pages[page]);
2692 			pd->data_address = cpu_to_le32(page_bus + offset);
2693 
2694 			offset = (offset + length) & ~PAGE_MASK;
2695 			rest -= length;
2696 			if (offset == 0)
2697 				page++;
2698 		}
2699 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2700 					  DESCRIPTOR_INPUT_LAST |
2701 					  DESCRIPTOR_BRANCH_ALWAYS);
2702 		if (packet->interrupt && i == packet_count - 1)
2703 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2704 
2705 		context_append(&ctx->context, d, z, header_z);
2706 	}
2707 
2708 	return 0;
2709 }
2710 
2711 static int queue_iso_buffer_fill(struct iso_context *ctx,
2712 				 struct fw_iso_packet *packet,
2713 				 struct fw_iso_buffer *buffer,
2714 				 unsigned long payload)
2715 {
2716 	struct descriptor *d;
2717 	dma_addr_t d_bus, page_bus;
2718 	int page, offset, rest, z, i, length;
2719 
2720 	page   = payload >> PAGE_SHIFT;
2721 	offset = payload & ~PAGE_MASK;
2722 	rest   = packet->payload_length;
2723 
2724 	/* We need one descriptor for each page in the buffer. */
2725 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
2726 
2727 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
2728 		return -EFAULT;
2729 
2730 	for (i = 0; i < z; i++) {
2731 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
2732 		if (d == NULL)
2733 			return -ENOMEM;
2734 
2735 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
2736 					 DESCRIPTOR_BRANCH_ALWAYS);
2737 		if (packet->skip && i == 0)
2738 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2739 		if (packet->interrupt && i == z - 1)
2740 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2741 
2742 		if (offset + rest < PAGE_SIZE)
2743 			length = rest;
2744 		else
2745 			length = PAGE_SIZE - offset;
2746 		d->req_count = cpu_to_le16(length);
2747 		d->res_count = d->req_count;
2748 		d->transfer_status = 0;
2749 
2750 		page_bus = page_private(buffer->pages[page]);
2751 		d->data_address = cpu_to_le32(page_bus + offset);
2752 
2753 		rest -= length;
2754 		offset = 0;
2755 		page++;
2756 
2757 		context_append(&ctx->context, d, 1, 0);
2758 	}
2759 
2760 	return 0;
2761 }
2762 
2763 static int ohci_queue_iso(struct fw_iso_context *base,
2764 			  struct fw_iso_packet *packet,
2765 			  struct fw_iso_buffer *buffer,
2766 			  unsigned long payload)
2767 {
2768 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2769 	unsigned long flags;
2770 	int ret = -ENOSYS;
2771 
2772 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
2773 	switch (base->type) {
2774 	case FW_ISO_CONTEXT_TRANSMIT:
2775 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
2776 		break;
2777 	case FW_ISO_CONTEXT_RECEIVE:
2778 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
2779 		break;
2780 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2781 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
2782 		break;
2783 	}
2784 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
2785 
2786 	return ret;
2787 }
2788 
2789 static const struct fw_card_driver ohci_driver = {
2790 	.enable			= ohci_enable,
2791 	.read_phy_reg		= ohci_read_phy_reg,
2792 	.update_phy_reg		= ohci_update_phy_reg,
2793 	.set_config_rom		= ohci_set_config_rom,
2794 	.send_request		= ohci_send_request,
2795 	.send_response		= ohci_send_response,
2796 	.cancel_packet		= ohci_cancel_packet,
2797 	.enable_phys_dma	= ohci_enable_phys_dma,
2798 	.read_csr		= ohci_read_csr,
2799 	.write_csr		= ohci_write_csr,
2800 
2801 	.allocate_iso_context	= ohci_allocate_iso_context,
2802 	.free_iso_context	= ohci_free_iso_context,
2803 	.set_iso_channels	= ohci_set_iso_channels,
2804 	.queue_iso		= ohci_queue_iso,
2805 	.start_iso		= ohci_start_iso,
2806 	.stop_iso		= ohci_stop_iso,
2807 };
2808 
2809 #ifdef CONFIG_PPC_PMAC
2810 static void pmac_ohci_on(struct pci_dev *dev)
2811 {
2812 	if (machine_is(powermac)) {
2813 		struct device_node *ofn = pci_device_to_OF_node(dev);
2814 
2815 		if (ofn) {
2816 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
2817 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
2818 		}
2819 	}
2820 }
2821 
2822 static void pmac_ohci_off(struct pci_dev *dev)
2823 {
2824 	if (machine_is(powermac)) {
2825 		struct device_node *ofn = pci_device_to_OF_node(dev);
2826 
2827 		if (ofn) {
2828 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
2829 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
2830 		}
2831 	}
2832 }
2833 #else
2834 static inline void pmac_ohci_on(struct pci_dev *dev) {}
2835 static inline void pmac_ohci_off(struct pci_dev *dev) {}
2836 #endif /* CONFIG_PPC_PMAC */
2837 
2838 static int __devinit pci_probe(struct pci_dev *dev,
2839 			       const struct pci_device_id *ent)
2840 {
2841 	struct fw_ohci *ohci;
2842 	u32 bus_options, max_receive, link_speed, version, link_enh;
2843 	u64 guid;
2844 	int i, err, n_ir, n_it;
2845 	size_t size;
2846 
2847 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
2848 	if (ohci == NULL) {
2849 		err = -ENOMEM;
2850 		goto fail;
2851 	}
2852 
2853 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
2854 
2855 	pmac_ohci_on(dev);
2856 
2857 	err = pci_enable_device(dev);
2858 	if (err) {
2859 		fw_error("Failed to enable OHCI hardware\n");
2860 		goto fail_free;
2861 	}
2862 
2863 	pci_set_master(dev);
2864 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
2865 	pci_set_drvdata(dev, ohci);
2866 
2867 	spin_lock_init(&ohci->lock);
2868 	mutex_init(&ohci->phy_reg_mutex);
2869 
2870 	tasklet_init(&ohci->bus_reset_tasklet,
2871 		     bus_reset_tasklet, (unsigned long)ohci);
2872 
2873 	err = pci_request_region(dev, 0, ohci_driver_name);
2874 	if (err) {
2875 		fw_error("MMIO resource unavailable\n");
2876 		goto fail_disable;
2877 	}
2878 
2879 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
2880 	if (ohci->registers == NULL) {
2881 		fw_error("Failed to remap registers\n");
2882 		err = -ENXIO;
2883 		goto fail_iomem;
2884 	}
2885 
2886 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
2887 		if (ohci_quirks[i].vendor == dev->vendor &&
2888 		    (ohci_quirks[i].device == dev->device ||
2889 		     ohci_quirks[i].device == (unsigned short)PCI_ANY_ID)) {
2890 			ohci->quirks = ohci_quirks[i].flags;
2891 			break;
2892 		}
2893 	if (param_quirks)
2894 		ohci->quirks = param_quirks;
2895 
2896 	/* TI OHCI-Lynx and compatible: set recommended configuration bits. */
2897 	if (dev->vendor == PCI_VENDOR_ID_TI) {
2898 		pci_read_config_dword(dev, PCI_CFG_TI_LinkEnh, &link_enh);
2899 
2900 		/* adjust latency of ATx FIFO: use 1.7 KB threshold */
2901 		link_enh &= ~TI_LinkEnh_atx_thresh_mask;
2902 		link_enh |= TI_LinkEnh_atx_thresh_1_7K;
2903 
2904 		/* use priority arbitration for asynchronous responses */
2905 		link_enh |= TI_LinkEnh_enab_unfair;
2906 
2907 		/* required for aPhyEnhanceEnable to work */
2908 		link_enh |= TI_LinkEnh_enab_accel;
2909 
2910 		pci_write_config_dword(dev, PCI_CFG_TI_LinkEnh, link_enh);
2911 	}
2912 
2913 	ar_context_init(&ohci->ar_request_ctx, ohci,
2914 			OHCI1394_AsReqRcvContextControlSet);
2915 
2916 	ar_context_init(&ohci->ar_response_ctx, ohci,
2917 			OHCI1394_AsRspRcvContextControlSet);
2918 
2919 	context_init(&ohci->at_request_ctx, ohci,
2920 		     OHCI1394_AsReqTrContextControlSet, handle_at_packet);
2921 
2922 	context_init(&ohci->at_response_ctx, ohci,
2923 		     OHCI1394_AsRspTrContextControlSet, handle_at_packet);
2924 
2925 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
2926 	ohci->ir_context_channels = ~0ULL;
2927 	ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
2928 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
2929 	n_ir = hweight32(ohci->ir_context_mask);
2930 	size = sizeof(struct iso_context) * n_ir;
2931 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
2932 
2933 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
2934 	ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
2935 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
2936 	n_it = hweight32(ohci->it_context_mask);
2937 	size = sizeof(struct iso_context) * n_it;
2938 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
2939 
2940 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
2941 		err = -ENOMEM;
2942 		goto fail_contexts;
2943 	}
2944 
2945 	/* self-id dma buffer allocation */
2946 	ohci->self_id_cpu = dma_alloc_coherent(ohci->card.device,
2947 					       SELF_ID_BUF_SIZE,
2948 					       &ohci->self_id_bus,
2949 					       GFP_KERNEL);
2950 	if (ohci->self_id_cpu == NULL) {
2951 		err = -ENOMEM;
2952 		goto fail_contexts;
2953 	}
2954 
2955 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
2956 	max_receive = (bus_options >> 12) & 0xf;
2957 	link_speed = bus_options & 0x7;
2958 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
2959 		reg_read(ohci, OHCI1394_GUIDLo);
2960 
2961 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
2962 	if (err)
2963 		goto fail_self_id;
2964 
2965 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2966 	fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
2967 		  "%d IR + %d IT contexts, quirks 0x%x\n",
2968 		  dev_name(&dev->dev), version >> 16, version & 0xff,
2969 		  n_ir, n_it, ohci->quirks);
2970 
2971 	return 0;
2972 
2973  fail_self_id:
2974 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
2975 			  ohci->self_id_cpu, ohci->self_id_bus);
2976  fail_contexts:
2977 	kfree(ohci->ir_context_list);
2978 	kfree(ohci->it_context_list);
2979 	context_release(&ohci->at_response_ctx);
2980 	context_release(&ohci->at_request_ctx);
2981 	ar_context_release(&ohci->ar_response_ctx);
2982 	ar_context_release(&ohci->ar_request_ctx);
2983 	pci_iounmap(dev, ohci->registers);
2984  fail_iomem:
2985 	pci_release_region(dev, 0);
2986  fail_disable:
2987 	pci_disable_device(dev);
2988  fail_free:
2989 	kfree(&ohci->card);
2990 	pmac_ohci_off(dev);
2991  fail:
2992 	if (err == -ENOMEM)
2993 		fw_error("Out of memory\n");
2994 
2995 	return err;
2996 }
2997 
2998 static void pci_remove(struct pci_dev *dev)
2999 {
3000 	struct fw_ohci *ohci;
3001 
3002 	ohci = pci_get_drvdata(dev);
3003 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3004 	flush_writes(ohci);
3005 	fw_core_remove_card(&ohci->card);
3006 
3007 	/*
3008 	 * FIXME: Fail all pending packets here, now that the upper
3009 	 * layers can't queue any more.
3010 	 */
3011 
3012 	software_reset(ohci);
3013 	free_irq(dev->irq, ohci);
3014 
3015 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3016 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3017 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3018 	if (ohci->config_rom)
3019 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3020 				  ohci->config_rom, ohci->config_rom_bus);
3021 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
3022 			  ohci->self_id_cpu, ohci->self_id_bus);
3023 	ar_context_release(&ohci->ar_request_ctx);
3024 	ar_context_release(&ohci->ar_response_ctx);
3025 	context_release(&ohci->at_request_ctx);
3026 	context_release(&ohci->at_response_ctx);
3027 	kfree(ohci->it_context_list);
3028 	kfree(ohci->ir_context_list);
3029 	pci_disable_msi(dev);
3030 	pci_iounmap(dev, ohci->registers);
3031 	pci_release_region(dev, 0);
3032 	pci_disable_device(dev);
3033 	kfree(&ohci->card);
3034 	pmac_ohci_off(dev);
3035 
3036 	fw_notify("Removed fw-ohci device.\n");
3037 }
3038 
3039 #ifdef CONFIG_PM
3040 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3041 {
3042 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3043 	int err;
3044 
3045 	software_reset(ohci);
3046 	free_irq(dev->irq, ohci);
3047 	pci_disable_msi(dev);
3048 	err = pci_save_state(dev);
3049 	if (err) {
3050 		fw_error("pci_save_state failed\n");
3051 		return err;
3052 	}
3053 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3054 	if (err)
3055 		fw_error("pci_set_power_state failed with %d\n", err);
3056 	pmac_ohci_off(dev);
3057 
3058 	return 0;
3059 }
3060 
3061 static int pci_resume(struct pci_dev *dev)
3062 {
3063 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3064 	int err;
3065 
3066 	pmac_ohci_on(dev);
3067 	pci_set_power_state(dev, PCI_D0);
3068 	pci_restore_state(dev);
3069 	err = pci_enable_device(dev);
3070 	if (err) {
3071 		fw_error("pci_enable_device failed\n");
3072 		return err;
3073 	}
3074 
3075 	return ohci_enable(&ohci->card, NULL, 0);
3076 }
3077 #endif
3078 
3079 static const struct pci_device_id pci_table[] = {
3080 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3081 	{ }
3082 };
3083 
3084 MODULE_DEVICE_TABLE(pci, pci_table);
3085 
3086 static struct pci_driver fw_ohci_pci_driver = {
3087 	.name		= ohci_driver_name,
3088 	.id_table	= pci_table,
3089 	.probe		= pci_probe,
3090 	.remove		= pci_remove,
3091 #ifdef CONFIG_PM
3092 	.resume		= pci_resume,
3093 	.suspend	= pci_suspend,
3094 #endif
3095 };
3096 
3097 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3098 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3099 MODULE_LICENSE("GPL");
3100 
3101 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3102 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3103 MODULE_ALIAS("ohci1394");
3104 #endif
3105 
3106 static int __init fw_ohci_init(void)
3107 {
3108 	return pci_register_driver(&fw_ohci_pci_driver);
3109 }
3110 
3111 static void __exit fw_ohci_cleanup(void)
3112 {
3113 	pci_unregister_driver(&fw_ohci_pci_driver);
3114 }
3115 
3116 module_init(fw_ohci_init);
3117 module_exit(fw_ohci_cleanup);
3118