xref: /openbmc/linux/drivers/firewire/ohci.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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_AGERE_FW643	0x5901
246 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
247 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
248 
249 #define QUIRK_CYCLE_TIMER		1
250 #define QUIRK_RESET_PACKET		2
251 #define QUIRK_BE_HEADERS		4
252 #define QUIRK_NO_1394A			8
253 #define QUIRK_NO_MSI			16
254 
255 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
256 static const struct {
257 	unsigned short vendor, device, revision, flags;
258 } ohci_quirks[] = {
259 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
260 		QUIRK_CYCLE_TIMER},
261 
262 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
263 		QUIRK_BE_HEADERS},
264 
265 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
266 		QUIRK_NO_MSI},
267 
268 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
269 		QUIRK_NO_MSI},
270 
271 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
272 		QUIRK_CYCLE_TIMER},
273 
274 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
275 		QUIRK_CYCLE_TIMER},
276 
277 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
278 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
279 
280 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
281 		QUIRK_RESET_PACKET},
282 
283 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
284 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
285 };
286 
287 /* This overrides anything that was found in ohci_quirks[]. */
288 static int param_quirks;
289 module_param_named(quirks, param_quirks, int, 0644);
290 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
291 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
292 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
293 	", AR/selfID endianess = "	__stringify(QUIRK_BE_HEADERS)
294 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
295 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
296 	")");
297 
298 #define OHCI_PARAM_DEBUG_AT_AR		1
299 #define OHCI_PARAM_DEBUG_SELFIDS	2
300 #define OHCI_PARAM_DEBUG_IRQS		4
301 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
302 
303 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
304 
305 static int param_debug;
306 module_param_named(debug, param_debug, int, 0644);
307 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
308 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
309 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
310 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
311 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
312 	", or a combination, or all = -1)");
313 
314 static void log_irqs(u32 evt)
315 {
316 	if (likely(!(param_debug &
317 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
318 		return;
319 
320 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
321 	    !(evt & OHCI1394_busReset))
322 		return;
323 
324 	fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
325 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
326 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
327 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
328 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
329 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
330 	    evt & OHCI1394_isochRx		? " IR"			: "",
331 	    evt & OHCI1394_isochTx		? " IT"			: "",
332 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
333 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
334 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
335 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
336 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
337 	    evt & OHCI1394_busReset		? " busReset"		: "",
338 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
339 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
340 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
341 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
342 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
343 		    OHCI1394_cycleInconsistent |
344 		    OHCI1394_regAccessFail | OHCI1394_busReset)
345 						? " ?"			: "");
346 }
347 
348 static const char *speed[] = {
349 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
350 };
351 static const char *power[] = {
352 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
353 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
354 };
355 static const char port[] = { '.', '-', 'p', 'c', };
356 
357 static char _p(u32 *s, int shift)
358 {
359 	return port[*s >> shift & 3];
360 }
361 
362 static void log_selfids(int node_id, int generation, int self_id_count, u32 *s)
363 {
364 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
365 		return;
366 
367 	fw_notify("%d selfIDs, generation %d, local node ID %04x\n",
368 		  self_id_count, generation, node_id);
369 
370 	for (; self_id_count--; ++s)
371 		if ((*s & 1 << 23) == 0)
372 			fw_notify("selfID 0: %08x, phy %d [%c%c%c] "
373 			    "%s gc=%d %s %s%s%s\n",
374 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
375 			    speed[*s >> 14 & 3], *s >> 16 & 63,
376 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
377 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
378 		else
379 			fw_notify("selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
380 			    *s, *s >> 24 & 63,
381 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
382 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
383 }
384 
385 static const char *evts[] = {
386 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
387 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
388 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
389 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
390 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
391 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
392 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
393 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
394 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
395 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
396 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
397 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
398 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
399 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
400 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
401 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
402 	[0x20] = "pending/cancelled",
403 };
404 static const char *tcodes[] = {
405 	[0x0] = "QW req",		[0x1] = "BW req",
406 	[0x2] = "W resp",		[0x3] = "-reserved-",
407 	[0x4] = "QR req",		[0x5] = "BR req",
408 	[0x6] = "QR resp",		[0x7] = "BR resp",
409 	[0x8] = "cycle start",		[0x9] = "Lk req",
410 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
411 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
412 	[0xe] = "link internal",	[0xf] = "-reserved-",
413 };
414 static const char *phys[] = {
415 	[0x0] = "phy config packet",	[0x1] = "link-on packet",
416 	[0x2] = "self-id packet",	[0x3] = "-reserved-",
417 };
418 
419 static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
420 {
421 	int tcode = header[0] >> 4 & 0xf;
422 	char specific[12];
423 
424 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
425 		return;
426 
427 	if (unlikely(evt >= ARRAY_SIZE(evts)))
428 			evt = 0x1f;
429 
430 	if (evt == OHCI1394_evt_bus_reset) {
431 		fw_notify("A%c evt_bus_reset, generation %d\n",
432 		    dir, (header[2] >> 16) & 0xff);
433 		return;
434 	}
435 
436 	if (header[0] == ~header[1]) {
437 		fw_notify("A%c %s, %s, %08x\n",
438 		    dir, evts[evt], phys[header[0] >> 30 & 0x3], header[0]);
439 		return;
440 	}
441 
442 	switch (tcode) {
443 	case 0x0: case 0x6: case 0x8:
444 		snprintf(specific, sizeof(specific), " = %08x",
445 			 be32_to_cpu((__force __be32)header[3]));
446 		break;
447 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
448 		snprintf(specific, sizeof(specific), " %x,%x",
449 			 header[3] >> 16, header[3] & 0xffff);
450 		break;
451 	default:
452 		specific[0] = '\0';
453 	}
454 
455 	switch (tcode) {
456 	case 0xe: case 0xa:
457 		fw_notify("A%c %s, %s\n", dir, evts[evt], tcodes[tcode]);
458 		break;
459 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
460 		fw_notify("A%c spd %x tl %02x, "
461 		    "%04x -> %04x, %s, "
462 		    "%s, %04x%08x%s\n",
463 		    dir, speed, header[0] >> 10 & 0x3f,
464 		    header[1] >> 16, header[0] >> 16, evts[evt],
465 		    tcodes[tcode], header[1] & 0xffff, header[2], specific);
466 		break;
467 	default:
468 		fw_notify("A%c spd %x tl %02x, "
469 		    "%04x -> %04x, %s, "
470 		    "%s%s\n",
471 		    dir, speed, header[0] >> 10 & 0x3f,
472 		    header[1] >> 16, header[0] >> 16, evts[evt],
473 		    tcodes[tcode], specific);
474 	}
475 }
476 
477 #else
478 
479 #define param_debug 0
480 static inline void log_irqs(u32 evt) {}
481 static inline void log_selfids(int node_id, int generation, int self_id_count, u32 *s) {}
482 static inline void log_ar_at_event(char dir, int speed, u32 *header, int evt) {}
483 
484 #endif /* CONFIG_FIREWIRE_OHCI_DEBUG */
485 
486 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
487 {
488 	writel(data, ohci->registers + offset);
489 }
490 
491 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
492 {
493 	return readl(ohci->registers + offset);
494 }
495 
496 static inline void flush_writes(const struct fw_ohci *ohci)
497 {
498 	/* Do a dummy read to flush writes. */
499 	reg_read(ohci, OHCI1394_Version);
500 }
501 
502 static int read_phy_reg(struct fw_ohci *ohci, int addr)
503 {
504 	u32 val;
505 	int i;
506 
507 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
508 	for (i = 0; i < 3 + 100; i++) {
509 		val = reg_read(ohci, OHCI1394_PhyControl);
510 		if (val & OHCI1394_PhyControl_ReadDone)
511 			return OHCI1394_PhyControl_ReadData(val);
512 
513 		/*
514 		 * Try a few times without waiting.  Sleeping is necessary
515 		 * only when the link/PHY interface is busy.
516 		 */
517 		if (i >= 3)
518 			msleep(1);
519 	}
520 	fw_error("failed to read phy reg\n");
521 
522 	return -EBUSY;
523 }
524 
525 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
526 {
527 	int i;
528 
529 	reg_write(ohci, OHCI1394_PhyControl,
530 		  OHCI1394_PhyControl_Write(addr, val));
531 	for (i = 0; i < 3 + 100; i++) {
532 		val = reg_read(ohci, OHCI1394_PhyControl);
533 		if (!(val & OHCI1394_PhyControl_WritePending))
534 			return 0;
535 
536 		if (i >= 3)
537 			msleep(1);
538 	}
539 	fw_error("failed to write phy reg\n");
540 
541 	return -EBUSY;
542 }
543 
544 static int update_phy_reg(struct fw_ohci *ohci, int addr,
545 			  int clear_bits, int set_bits)
546 {
547 	int ret = read_phy_reg(ohci, addr);
548 	if (ret < 0)
549 		return ret;
550 
551 	/*
552 	 * The interrupt status bits are cleared by writing a one bit.
553 	 * Avoid clearing them unless explicitly requested in set_bits.
554 	 */
555 	if (addr == 5)
556 		clear_bits |= PHY_INT_STATUS_BITS;
557 
558 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
559 }
560 
561 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
562 {
563 	int ret;
564 
565 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
566 	if (ret < 0)
567 		return ret;
568 
569 	return read_phy_reg(ohci, addr);
570 }
571 
572 static int ohci_read_phy_reg(struct fw_card *card, int addr)
573 {
574 	struct fw_ohci *ohci = fw_ohci(card);
575 	int ret;
576 
577 	mutex_lock(&ohci->phy_reg_mutex);
578 	ret = read_phy_reg(ohci, addr);
579 	mutex_unlock(&ohci->phy_reg_mutex);
580 
581 	return ret;
582 }
583 
584 static int ohci_update_phy_reg(struct fw_card *card, int addr,
585 			       int clear_bits, int set_bits)
586 {
587 	struct fw_ohci *ohci = fw_ohci(card);
588 	int ret;
589 
590 	mutex_lock(&ohci->phy_reg_mutex);
591 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
592 	mutex_unlock(&ohci->phy_reg_mutex);
593 
594 	return ret;
595 }
596 
597 static void ar_context_link_page(struct ar_context *ctx,
598 				 struct ar_buffer *ab, dma_addr_t ab_bus)
599 {
600 	size_t offset;
601 
602 	ab->next = NULL;
603 	memset(&ab->descriptor, 0, sizeof(ab->descriptor));
604 	ab->descriptor.control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
605 						    DESCRIPTOR_STATUS |
606 						    DESCRIPTOR_BRANCH_ALWAYS);
607 	offset = offsetof(struct ar_buffer, data);
608 	ab->descriptor.req_count      = cpu_to_le16(PAGE_SIZE - offset);
609 	ab->descriptor.data_address   = cpu_to_le32(ab_bus + offset);
610 	ab->descriptor.res_count      = cpu_to_le16(PAGE_SIZE - offset);
611 	ab->descriptor.branch_address = 0;
612 
613 	wmb(); /* finish init of new descriptors before branch_address update */
614 	ctx->last_buffer->descriptor.branch_address = cpu_to_le32(ab_bus | 1);
615 	ctx->last_buffer->next = ab;
616 	ctx->last_buffer = ab;
617 
618 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
619 	flush_writes(ctx->ohci);
620 }
621 
622 static int ar_context_add_page(struct ar_context *ctx)
623 {
624 	struct device *dev = ctx->ohci->card.device;
625 	struct ar_buffer *ab;
626 	dma_addr_t uninitialized_var(ab_bus);
627 
628 	ab = dma_alloc_coherent(dev, PAGE_SIZE, &ab_bus, GFP_ATOMIC);
629 	if (ab == NULL)
630 		return -ENOMEM;
631 
632 	ar_context_link_page(ctx, ab, ab_bus);
633 
634 	return 0;
635 }
636 
637 static void ar_context_release(struct ar_context *ctx)
638 {
639 	struct ar_buffer *ab, *ab_next;
640 	size_t offset;
641 	dma_addr_t ab_bus;
642 
643 	for (ab = ctx->current_buffer; ab; ab = ab_next) {
644 		ab_next = ab->next;
645 		offset = offsetof(struct ar_buffer, data);
646 		ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
647 		dma_free_coherent(ctx->ohci->card.device, PAGE_SIZE,
648 				  ab, ab_bus);
649 	}
650 }
651 
652 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
653 #define cond_le32_to_cpu(v) \
654 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
655 #else
656 #define cond_le32_to_cpu(v) le32_to_cpu(v)
657 #endif
658 
659 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
660 {
661 	struct fw_ohci *ohci = ctx->ohci;
662 	struct fw_packet p;
663 	u32 status, length, tcode;
664 	int evt;
665 
666 	p.header[0] = cond_le32_to_cpu(buffer[0]);
667 	p.header[1] = cond_le32_to_cpu(buffer[1]);
668 	p.header[2] = cond_le32_to_cpu(buffer[2]);
669 
670 	tcode = (p.header[0] >> 4) & 0x0f;
671 	switch (tcode) {
672 	case TCODE_WRITE_QUADLET_REQUEST:
673 	case TCODE_READ_QUADLET_RESPONSE:
674 		p.header[3] = (__force __u32) buffer[3];
675 		p.header_length = 16;
676 		p.payload_length = 0;
677 		break;
678 
679 	case TCODE_READ_BLOCK_REQUEST :
680 		p.header[3] = cond_le32_to_cpu(buffer[3]);
681 		p.header_length = 16;
682 		p.payload_length = 0;
683 		break;
684 
685 	case TCODE_WRITE_BLOCK_REQUEST:
686 	case TCODE_READ_BLOCK_RESPONSE:
687 	case TCODE_LOCK_REQUEST:
688 	case TCODE_LOCK_RESPONSE:
689 		p.header[3] = cond_le32_to_cpu(buffer[3]);
690 		p.header_length = 16;
691 		p.payload_length = p.header[3] >> 16;
692 		break;
693 
694 	case TCODE_WRITE_RESPONSE:
695 	case TCODE_READ_QUADLET_REQUEST:
696 	case OHCI_TCODE_PHY_PACKET:
697 		p.header_length = 12;
698 		p.payload_length = 0;
699 		break;
700 
701 	default:
702 		/* FIXME: Stop context, discard everything, and restart? */
703 		p.header_length = 0;
704 		p.payload_length = 0;
705 	}
706 
707 	p.payload = (void *) buffer + p.header_length;
708 
709 	/* FIXME: What to do about evt_* errors? */
710 	length = (p.header_length + p.payload_length + 3) / 4;
711 	status = cond_le32_to_cpu(buffer[length]);
712 	evt    = (status >> 16) & 0x1f;
713 
714 	p.ack        = evt - 16;
715 	p.speed      = (status >> 21) & 0x7;
716 	p.timestamp  = status & 0xffff;
717 	p.generation = ohci->request_generation;
718 
719 	log_ar_at_event('R', p.speed, p.header, evt);
720 
721 	/*
722 	 * Several controllers, notably from NEC and VIA, forget to
723 	 * write ack_complete status at PHY packet reception.
724 	 */
725 	if (evt == OHCI1394_evt_no_status &&
726 	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
727 		p.ack = ACK_COMPLETE;
728 
729 	/*
730 	 * The OHCI bus reset handler synthesizes a PHY packet with
731 	 * the new generation number when a bus reset happens (see
732 	 * section 8.4.2.3).  This helps us determine when a request
733 	 * was received and make sure we send the response in the same
734 	 * generation.  We only need this for requests; for responses
735 	 * we use the unique tlabel for finding the matching
736 	 * request.
737 	 *
738 	 * Alas some chips sometimes emit bus reset packets with a
739 	 * wrong generation.  We set the correct generation for these
740 	 * at a slightly incorrect time (in bus_reset_tasklet).
741 	 */
742 	if (evt == OHCI1394_evt_bus_reset) {
743 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
744 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
745 	} else if (ctx == &ohci->ar_request_ctx) {
746 		fw_core_handle_request(&ohci->card, &p);
747 	} else {
748 		fw_core_handle_response(&ohci->card, &p);
749 	}
750 
751 	return buffer + length + 1;
752 }
753 
754 static void ar_context_tasklet(unsigned long data)
755 {
756 	struct ar_context *ctx = (struct ar_context *)data;
757 	struct ar_buffer *ab;
758 	struct descriptor *d;
759 	void *buffer, *end;
760 	__le16 res_count;
761 
762 	ab = ctx->current_buffer;
763 	d = &ab->descriptor;
764 
765 	res_count = ACCESS_ONCE(d->res_count);
766 	if (res_count == 0) {
767 		size_t size, size2, rest, pktsize, size3, offset;
768 		dma_addr_t start_bus;
769 		void *start;
770 
771 		/*
772 		 * This descriptor is finished and we may have a
773 		 * packet split across this and the next buffer. We
774 		 * reuse the page for reassembling the split packet.
775 		 */
776 
777 		offset = offsetof(struct ar_buffer, data);
778 		start = ab;
779 		start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
780 		buffer = ab->data;
781 
782 		ab = ab->next;
783 		d = &ab->descriptor;
784 		size = start + PAGE_SIZE - ctx->pointer;
785 		/* valid buffer data in the next page */
786 		rest = le16_to_cpu(d->req_count) - le16_to_cpu(d->res_count);
787 		/* what actually fits in this page */
788 		size2 = min(rest, (size_t)PAGE_SIZE - offset - size);
789 		memmove(buffer, ctx->pointer, size);
790 		memcpy(buffer + size, ab->data, size2);
791 
792 		while (size > 0) {
793 			void *next = handle_ar_packet(ctx, buffer);
794 			pktsize = next - buffer;
795 			if (pktsize >= size) {
796 				/*
797 				 * We have handled all the data that was
798 				 * originally in this page, so we can now
799 				 * continue in the next page.
800 				 */
801 				buffer = next;
802 				break;
803 			}
804 			/* move the next packet to the start of the buffer */
805 			memmove(buffer, next, size + size2 - pktsize);
806 			size -= pktsize;
807 			/* fill up this page again */
808 			size3 = min(rest - size2,
809 				    (size_t)PAGE_SIZE - offset - size - size2);
810 			memcpy(buffer + size + size2,
811 			       (void *) ab->data + size2, size3);
812 			size2 += size3;
813 		}
814 
815 		if (rest > 0) {
816 			/* handle the packets that are fully in the next page */
817 			buffer = (void *) ab->data +
818 					(buffer - (start + offset + size));
819 			end = (void *) ab->data + rest;
820 
821 			while (buffer < end)
822 				buffer = handle_ar_packet(ctx, buffer);
823 
824 			ctx->current_buffer = ab;
825 			ctx->pointer = end;
826 
827 			ar_context_link_page(ctx, start, start_bus);
828 		} else {
829 			ctx->pointer = start + PAGE_SIZE;
830 		}
831 	} else {
832 		buffer = ctx->pointer;
833 		ctx->pointer = end =
834 			(void *) ab + PAGE_SIZE - le16_to_cpu(res_count);
835 
836 		while (buffer < end)
837 			buffer = handle_ar_packet(ctx, buffer);
838 	}
839 }
840 
841 static int ar_context_init(struct ar_context *ctx,
842 			   struct fw_ohci *ohci, u32 regs)
843 {
844 	struct ar_buffer ab;
845 
846 	ctx->regs        = regs;
847 	ctx->ohci        = ohci;
848 	ctx->last_buffer = &ab;
849 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
850 
851 	ar_context_add_page(ctx);
852 	ar_context_add_page(ctx);
853 	ctx->current_buffer = ab.next;
854 	ctx->pointer = ctx->current_buffer->data;
855 
856 	return 0;
857 }
858 
859 static void ar_context_run(struct ar_context *ctx)
860 {
861 	struct ar_buffer *ab = ctx->current_buffer;
862 	dma_addr_t ab_bus;
863 	size_t offset;
864 
865 	offset = offsetof(struct ar_buffer, data);
866 	ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
867 
868 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ab_bus | 1);
869 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
870 	flush_writes(ctx->ohci);
871 }
872 
873 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
874 {
875 	int b, key;
876 
877 	b   = (le16_to_cpu(d->control) & DESCRIPTOR_BRANCH_ALWAYS) >> 2;
878 	key = (le16_to_cpu(d->control) & DESCRIPTOR_KEY_IMMEDIATE) >> 8;
879 
880 	/* figure out which descriptor the branch address goes in */
881 	if (z == 2 && (b == 3 || key == 2))
882 		return d;
883 	else
884 		return d + z - 1;
885 }
886 
887 static void context_tasklet(unsigned long data)
888 {
889 	struct context *ctx = (struct context *) data;
890 	struct descriptor *d, *last;
891 	u32 address;
892 	int z;
893 	struct descriptor_buffer *desc;
894 
895 	desc = list_entry(ctx->buffer_list.next,
896 			struct descriptor_buffer, list);
897 	last = ctx->last;
898 	while (last->branch_address != 0) {
899 		struct descriptor_buffer *old_desc = desc;
900 		address = le32_to_cpu(last->branch_address);
901 		z = address & 0xf;
902 		address &= ~0xf;
903 
904 		/* If the branch address points to a buffer outside of the
905 		 * current buffer, advance to the next buffer. */
906 		if (address < desc->buffer_bus ||
907 				address >= desc->buffer_bus + desc->used)
908 			desc = list_entry(desc->list.next,
909 					struct descriptor_buffer, list);
910 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
911 		last = find_branch_descriptor(d, z);
912 
913 		if (!ctx->callback(ctx, d, last))
914 			break;
915 
916 		if (old_desc != desc) {
917 			/* If we've advanced to the next buffer, move the
918 			 * previous buffer to the free list. */
919 			unsigned long flags;
920 			old_desc->used = 0;
921 			spin_lock_irqsave(&ctx->ohci->lock, flags);
922 			list_move_tail(&old_desc->list, &ctx->buffer_list);
923 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
924 		}
925 		ctx->last = last;
926 	}
927 }
928 
929 /*
930  * Allocate a new buffer and add it to the list of free buffers for this
931  * context.  Must be called with ohci->lock held.
932  */
933 static int context_add_buffer(struct context *ctx)
934 {
935 	struct descriptor_buffer *desc;
936 	dma_addr_t uninitialized_var(bus_addr);
937 	int offset;
938 
939 	/*
940 	 * 16MB of descriptors should be far more than enough for any DMA
941 	 * program.  This will catch run-away userspace or DoS attacks.
942 	 */
943 	if (ctx->total_allocation >= 16*1024*1024)
944 		return -ENOMEM;
945 
946 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
947 			&bus_addr, GFP_ATOMIC);
948 	if (!desc)
949 		return -ENOMEM;
950 
951 	offset = (void *)&desc->buffer - (void *)desc;
952 	desc->buffer_size = PAGE_SIZE - offset;
953 	desc->buffer_bus = bus_addr + offset;
954 	desc->used = 0;
955 
956 	list_add_tail(&desc->list, &ctx->buffer_list);
957 	ctx->total_allocation += PAGE_SIZE;
958 
959 	return 0;
960 }
961 
962 static int context_init(struct context *ctx, struct fw_ohci *ohci,
963 			u32 regs, descriptor_callback_t callback)
964 {
965 	ctx->ohci = ohci;
966 	ctx->regs = regs;
967 	ctx->total_allocation = 0;
968 
969 	INIT_LIST_HEAD(&ctx->buffer_list);
970 	if (context_add_buffer(ctx) < 0)
971 		return -ENOMEM;
972 
973 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
974 			struct descriptor_buffer, list);
975 
976 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
977 	ctx->callback = callback;
978 
979 	/*
980 	 * We put a dummy descriptor in the buffer that has a NULL
981 	 * branch address and looks like it's been sent.  That way we
982 	 * have a descriptor to append DMA programs to.
983 	 */
984 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
985 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
986 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
987 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
988 	ctx->last = ctx->buffer_tail->buffer;
989 	ctx->prev = ctx->buffer_tail->buffer;
990 
991 	return 0;
992 }
993 
994 static void context_release(struct context *ctx)
995 {
996 	struct fw_card *card = &ctx->ohci->card;
997 	struct descriptor_buffer *desc, *tmp;
998 
999 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1000 		dma_free_coherent(card->device, PAGE_SIZE, desc,
1001 			desc->buffer_bus -
1002 			((void *)&desc->buffer - (void *)desc));
1003 }
1004 
1005 /* Must be called with ohci->lock held */
1006 static struct descriptor *context_get_descriptors(struct context *ctx,
1007 						  int z, dma_addr_t *d_bus)
1008 {
1009 	struct descriptor *d = NULL;
1010 	struct descriptor_buffer *desc = ctx->buffer_tail;
1011 
1012 	if (z * sizeof(*d) > desc->buffer_size)
1013 		return NULL;
1014 
1015 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1016 		/* No room for the descriptor in this buffer, so advance to the
1017 		 * next one. */
1018 
1019 		if (desc->list.next == &ctx->buffer_list) {
1020 			/* If there is no free buffer next in the list,
1021 			 * allocate one. */
1022 			if (context_add_buffer(ctx) < 0)
1023 				return NULL;
1024 		}
1025 		desc = list_entry(desc->list.next,
1026 				struct descriptor_buffer, list);
1027 		ctx->buffer_tail = desc;
1028 	}
1029 
1030 	d = desc->buffer + desc->used / sizeof(*d);
1031 	memset(d, 0, z * sizeof(*d));
1032 	*d_bus = desc->buffer_bus + desc->used;
1033 
1034 	return d;
1035 }
1036 
1037 static void context_run(struct context *ctx, u32 extra)
1038 {
1039 	struct fw_ohci *ohci = ctx->ohci;
1040 
1041 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1042 		  le32_to_cpu(ctx->last->branch_address));
1043 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1044 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1045 	flush_writes(ohci);
1046 }
1047 
1048 static void context_append(struct context *ctx,
1049 			   struct descriptor *d, int z, int extra)
1050 {
1051 	dma_addr_t d_bus;
1052 	struct descriptor_buffer *desc = ctx->buffer_tail;
1053 
1054 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1055 
1056 	desc->used += (z + extra) * sizeof(*d);
1057 
1058 	wmb(); /* finish init of new descriptors before branch_address update */
1059 	ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1060 	ctx->prev = find_branch_descriptor(d, z);
1061 
1062 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1063 	flush_writes(ctx->ohci);
1064 }
1065 
1066 static void context_stop(struct context *ctx)
1067 {
1068 	u32 reg;
1069 	int i;
1070 
1071 	reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1072 	flush_writes(ctx->ohci);
1073 
1074 	for (i = 0; i < 10; i++) {
1075 		reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1076 		if ((reg & CONTEXT_ACTIVE) == 0)
1077 			return;
1078 
1079 		mdelay(1);
1080 	}
1081 	fw_error("Error: DMA context still active (0x%08x)\n", reg);
1082 }
1083 
1084 struct driver_data {
1085 	struct fw_packet *packet;
1086 };
1087 
1088 /*
1089  * This function apppends a packet to the DMA queue for transmission.
1090  * Must always be called with the ochi->lock held to ensure proper
1091  * generation handling and locking around packet queue manipulation.
1092  */
1093 static int at_context_queue_packet(struct context *ctx,
1094 				   struct fw_packet *packet)
1095 {
1096 	struct fw_ohci *ohci = ctx->ohci;
1097 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1098 	struct driver_data *driver_data;
1099 	struct descriptor *d, *last;
1100 	__le32 *header;
1101 	int z, tcode;
1102 	u32 reg;
1103 
1104 	d = context_get_descriptors(ctx, 4, &d_bus);
1105 	if (d == NULL) {
1106 		packet->ack = RCODE_SEND_ERROR;
1107 		return -1;
1108 	}
1109 
1110 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1111 	d[0].res_count = cpu_to_le16(packet->timestamp);
1112 
1113 	/*
1114 	 * The DMA format for asyncronous link packets is different
1115 	 * from the IEEE1394 layout, so shift the fields around
1116 	 * accordingly.  If header_length is 8, it's a PHY packet, to
1117 	 * which we need to prepend an extra quadlet.
1118 	 */
1119 
1120 	header = (__le32 *) &d[1];
1121 	switch (packet->header_length) {
1122 	case 16:
1123 	case 12:
1124 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1125 					(packet->speed << 16));
1126 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1127 					(packet->header[0] & 0xffff0000));
1128 		header[2] = cpu_to_le32(packet->header[2]);
1129 
1130 		tcode = (packet->header[0] >> 4) & 0x0f;
1131 		if (TCODE_IS_BLOCK_PACKET(tcode))
1132 			header[3] = cpu_to_le32(packet->header[3]);
1133 		else
1134 			header[3] = (__force __le32) packet->header[3];
1135 
1136 		d[0].req_count = cpu_to_le16(packet->header_length);
1137 		break;
1138 
1139 	case 8:
1140 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1141 					(packet->speed << 16));
1142 		header[1] = cpu_to_le32(packet->header[0]);
1143 		header[2] = cpu_to_le32(packet->header[1]);
1144 		d[0].req_count = cpu_to_le16(12);
1145 
1146 		if (is_ping_packet(packet->header))
1147 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1148 		break;
1149 
1150 	case 4:
1151 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1152 					(packet->speed << 16));
1153 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1154 		d[0].req_count = cpu_to_le16(8);
1155 		break;
1156 
1157 	default:
1158 		/* BUG(); */
1159 		packet->ack = RCODE_SEND_ERROR;
1160 		return -1;
1161 	}
1162 
1163 	driver_data = (struct driver_data *) &d[3];
1164 	driver_data->packet = packet;
1165 	packet->driver_data = driver_data;
1166 
1167 	if (packet->payload_length > 0) {
1168 		payload_bus =
1169 			dma_map_single(ohci->card.device, packet->payload,
1170 				       packet->payload_length, DMA_TO_DEVICE);
1171 		if (dma_mapping_error(ohci->card.device, payload_bus)) {
1172 			packet->ack = RCODE_SEND_ERROR;
1173 			return -1;
1174 		}
1175 		packet->payload_bus	= payload_bus;
1176 		packet->payload_mapped	= true;
1177 
1178 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1179 		d[2].data_address = cpu_to_le32(payload_bus);
1180 		last = &d[2];
1181 		z = 3;
1182 	} else {
1183 		last = &d[0];
1184 		z = 2;
1185 	}
1186 
1187 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1188 				     DESCRIPTOR_IRQ_ALWAYS |
1189 				     DESCRIPTOR_BRANCH_ALWAYS);
1190 
1191 	/*
1192 	 * If the controller and packet generations don't match, we need to
1193 	 * bail out and try again.  If IntEvent.busReset is set, the AT context
1194 	 * is halted, so appending to the context and trying to run it is
1195 	 * futile.  Most controllers do the right thing and just flush the AT
1196 	 * queue (per section 7.2.3.2 of the OHCI 1.1 specification), but
1197 	 * some controllers (like a JMicron JMB381 PCI-e) misbehave and wind
1198 	 * up stalling out.  So we just bail out in software and try again
1199 	 * later, and everyone is happy.
1200 	 * FIXME: Document how the locking works.
1201 	 */
1202 	if (ohci->generation != packet->generation ||
1203 	    reg_read(ohci, OHCI1394_IntEventSet) & OHCI1394_busReset) {
1204 		if (packet->payload_mapped)
1205 			dma_unmap_single(ohci->card.device, payload_bus,
1206 					 packet->payload_length, DMA_TO_DEVICE);
1207 		packet->ack = RCODE_GENERATION;
1208 		return -1;
1209 	}
1210 
1211 	context_append(ctx, d, z, 4 - z);
1212 
1213 	/* If the context isn't already running, start it up. */
1214 	reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1215 	if ((reg & CONTEXT_RUN) == 0)
1216 		context_run(ctx, 0);
1217 
1218 	return 0;
1219 }
1220 
1221 static int handle_at_packet(struct context *context,
1222 			    struct descriptor *d,
1223 			    struct descriptor *last)
1224 {
1225 	struct driver_data *driver_data;
1226 	struct fw_packet *packet;
1227 	struct fw_ohci *ohci = context->ohci;
1228 	int evt;
1229 
1230 	if (last->transfer_status == 0)
1231 		/* This descriptor isn't done yet, stop iteration. */
1232 		return 0;
1233 
1234 	driver_data = (struct driver_data *) &d[3];
1235 	packet = driver_data->packet;
1236 	if (packet == NULL)
1237 		/* This packet was cancelled, just continue. */
1238 		return 1;
1239 
1240 	if (packet->payload_mapped)
1241 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1242 				 packet->payload_length, DMA_TO_DEVICE);
1243 
1244 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1245 	packet->timestamp = le16_to_cpu(last->res_count);
1246 
1247 	log_ar_at_event('T', packet->speed, packet->header, evt);
1248 
1249 	switch (evt) {
1250 	case OHCI1394_evt_timeout:
1251 		/* Async response transmit timed out. */
1252 		packet->ack = RCODE_CANCELLED;
1253 		break;
1254 
1255 	case OHCI1394_evt_flushed:
1256 		/*
1257 		 * The packet was flushed should give same error as
1258 		 * when we try to use a stale generation count.
1259 		 */
1260 		packet->ack = RCODE_GENERATION;
1261 		break;
1262 
1263 	case OHCI1394_evt_missing_ack:
1264 		/*
1265 		 * Using a valid (current) generation count, but the
1266 		 * node is not on the bus or not sending acks.
1267 		 */
1268 		packet->ack = RCODE_NO_ACK;
1269 		break;
1270 
1271 	case ACK_COMPLETE + 0x10:
1272 	case ACK_PENDING + 0x10:
1273 	case ACK_BUSY_X + 0x10:
1274 	case ACK_BUSY_A + 0x10:
1275 	case ACK_BUSY_B + 0x10:
1276 	case ACK_DATA_ERROR + 0x10:
1277 	case ACK_TYPE_ERROR + 0x10:
1278 		packet->ack = evt - 0x10;
1279 		break;
1280 
1281 	default:
1282 		packet->ack = RCODE_SEND_ERROR;
1283 		break;
1284 	}
1285 
1286 	packet->callback(packet, &ohci->card, packet->ack);
1287 
1288 	return 1;
1289 }
1290 
1291 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1292 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1293 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1294 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1295 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1296 
1297 static void handle_local_rom(struct fw_ohci *ohci,
1298 			     struct fw_packet *packet, u32 csr)
1299 {
1300 	struct fw_packet response;
1301 	int tcode, length, i;
1302 
1303 	tcode = HEADER_GET_TCODE(packet->header[0]);
1304 	if (TCODE_IS_BLOCK_PACKET(tcode))
1305 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1306 	else
1307 		length = 4;
1308 
1309 	i = csr - CSR_CONFIG_ROM;
1310 	if (i + length > CONFIG_ROM_SIZE) {
1311 		fw_fill_response(&response, packet->header,
1312 				 RCODE_ADDRESS_ERROR, NULL, 0);
1313 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1314 		fw_fill_response(&response, packet->header,
1315 				 RCODE_TYPE_ERROR, NULL, 0);
1316 	} else {
1317 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1318 				 (void *) ohci->config_rom + i, length);
1319 	}
1320 
1321 	fw_core_handle_response(&ohci->card, &response);
1322 }
1323 
1324 static void handle_local_lock(struct fw_ohci *ohci,
1325 			      struct fw_packet *packet, u32 csr)
1326 {
1327 	struct fw_packet response;
1328 	int tcode, length, ext_tcode, sel, try;
1329 	__be32 *payload, lock_old;
1330 	u32 lock_arg, lock_data;
1331 
1332 	tcode = HEADER_GET_TCODE(packet->header[0]);
1333 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1334 	payload = packet->payload;
1335 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1336 
1337 	if (tcode == TCODE_LOCK_REQUEST &&
1338 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1339 		lock_arg = be32_to_cpu(payload[0]);
1340 		lock_data = be32_to_cpu(payload[1]);
1341 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1342 		lock_arg = 0;
1343 		lock_data = 0;
1344 	} else {
1345 		fw_fill_response(&response, packet->header,
1346 				 RCODE_TYPE_ERROR, NULL, 0);
1347 		goto out;
1348 	}
1349 
1350 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1351 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1352 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1353 	reg_write(ohci, OHCI1394_CSRControl, sel);
1354 
1355 	for (try = 0; try < 20; try++)
1356 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1357 			lock_old = cpu_to_be32(reg_read(ohci,
1358 							OHCI1394_CSRData));
1359 			fw_fill_response(&response, packet->header,
1360 					 RCODE_COMPLETE,
1361 					 &lock_old, sizeof(lock_old));
1362 			goto out;
1363 		}
1364 
1365 	fw_error("swap not done (CSR lock timeout)\n");
1366 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1367 
1368  out:
1369 	fw_core_handle_response(&ohci->card, &response);
1370 }
1371 
1372 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1373 {
1374 	u64 offset, csr;
1375 
1376 	if (ctx == &ctx->ohci->at_request_ctx) {
1377 		packet->ack = ACK_PENDING;
1378 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1379 	}
1380 
1381 	offset =
1382 		((unsigned long long)
1383 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1384 		packet->header[2];
1385 	csr = offset - CSR_REGISTER_BASE;
1386 
1387 	/* Handle config rom reads. */
1388 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1389 		handle_local_rom(ctx->ohci, packet, csr);
1390 	else switch (csr) {
1391 	case CSR_BUS_MANAGER_ID:
1392 	case CSR_BANDWIDTH_AVAILABLE:
1393 	case CSR_CHANNELS_AVAILABLE_HI:
1394 	case CSR_CHANNELS_AVAILABLE_LO:
1395 		handle_local_lock(ctx->ohci, packet, csr);
1396 		break;
1397 	default:
1398 		if (ctx == &ctx->ohci->at_request_ctx)
1399 			fw_core_handle_request(&ctx->ohci->card, packet);
1400 		else
1401 			fw_core_handle_response(&ctx->ohci->card, packet);
1402 		break;
1403 	}
1404 
1405 	if (ctx == &ctx->ohci->at_response_ctx) {
1406 		packet->ack = ACK_COMPLETE;
1407 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1408 	}
1409 }
1410 
1411 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1412 {
1413 	unsigned long flags;
1414 	int ret;
1415 
1416 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1417 
1418 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1419 	    ctx->ohci->generation == packet->generation) {
1420 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1421 		handle_local_request(ctx, packet);
1422 		return;
1423 	}
1424 
1425 	ret = at_context_queue_packet(ctx, packet);
1426 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1427 
1428 	if (ret < 0)
1429 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1430 
1431 }
1432 
1433 static u32 cycle_timer_ticks(u32 cycle_timer)
1434 {
1435 	u32 ticks;
1436 
1437 	ticks = cycle_timer & 0xfff;
1438 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1439 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1440 
1441 	return ticks;
1442 }
1443 
1444 /*
1445  * Some controllers exhibit one or more of the following bugs when updating the
1446  * iso cycle timer register:
1447  *  - When the lowest six bits are wrapping around to zero, a read that happens
1448  *    at the same time will return garbage in the lowest ten bits.
1449  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1450  *    not incremented for about 60 ns.
1451  *  - Occasionally, the entire register reads zero.
1452  *
1453  * To catch these, we read the register three times and ensure that the
1454  * difference between each two consecutive reads is approximately the same, i.e.
1455  * less than twice the other.  Furthermore, any negative difference indicates an
1456  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1457  * execute, so we have enough precision to compute the ratio of the differences.)
1458  */
1459 static u32 get_cycle_time(struct fw_ohci *ohci)
1460 {
1461 	u32 c0, c1, c2;
1462 	u32 t0, t1, t2;
1463 	s32 diff01, diff12;
1464 	int i;
1465 
1466 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1467 
1468 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1469 		i = 0;
1470 		c1 = c2;
1471 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1472 		do {
1473 			c0 = c1;
1474 			c1 = c2;
1475 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1476 			t0 = cycle_timer_ticks(c0);
1477 			t1 = cycle_timer_ticks(c1);
1478 			t2 = cycle_timer_ticks(c2);
1479 			diff01 = t1 - t0;
1480 			diff12 = t2 - t1;
1481 		} while ((diff01 <= 0 || diff12 <= 0 ||
1482 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1483 			 && i++ < 20);
1484 	}
1485 
1486 	return c2;
1487 }
1488 
1489 /*
1490  * This function has to be called at least every 64 seconds.  The bus_time
1491  * field stores not only the upper 25 bits of the BUS_TIME register but also
1492  * the most significant bit of the cycle timer in bit 6 so that we can detect
1493  * changes in this bit.
1494  */
1495 static u32 update_bus_time(struct fw_ohci *ohci)
1496 {
1497 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1498 
1499 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1500 		ohci->bus_time += 0x40;
1501 
1502 	return ohci->bus_time | cycle_time_seconds;
1503 }
1504 
1505 static void bus_reset_tasklet(unsigned long data)
1506 {
1507 	struct fw_ohci *ohci = (struct fw_ohci *)data;
1508 	int self_id_count, i, j, reg;
1509 	int generation, new_generation;
1510 	unsigned long flags;
1511 	void *free_rom = NULL;
1512 	dma_addr_t free_rom_bus = 0;
1513 	bool is_new_root;
1514 
1515 	reg = reg_read(ohci, OHCI1394_NodeID);
1516 	if (!(reg & OHCI1394_NodeID_idValid)) {
1517 		fw_notify("node ID not valid, new bus reset in progress\n");
1518 		return;
1519 	}
1520 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1521 		fw_notify("malconfigured bus\n");
1522 		return;
1523 	}
1524 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1525 			       OHCI1394_NodeID_nodeNumber);
1526 
1527 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1528 	if (!(ohci->is_root && is_new_root))
1529 		reg_write(ohci, OHCI1394_LinkControlSet,
1530 			  OHCI1394_LinkControl_cycleMaster);
1531 	ohci->is_root = is_new_root;
1532 
1533 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1534 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1535 		fw_notify("inconsistent self IDs\n");
1536 		return;
1537 	}
1538 	/*
1539 	 * The count in the SelfIDCount register is the number of
1540 	 * bytes in the self ID receive buffer.  Since we also receive
1541 	 * the inverted quadlets and a header quadlet, we shift one
1542 	 * bit extra to get the actual number of self IDs.
1543 	 */
1544 	self_id_count = (reg >> 3) & 0xff;
1545 	if (self_id_count == 0 || self_id_count > 252) {
1546 		fw_notify("inconsistent self IDs\n");
1547 		return;
1548 	}
1549 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1550 	rmb();
1551 
1552 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1553 		if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1554 			fw_notify("inconsistent self IDs\n");
1555 			return;
1556 		}
1557 		ohci->self_id_buffer[j] =
1558 				cond_le32_to_cpu(ohci->self_id_cpu[i]);
1559 	}
1560 	rmb();
1561 
1562 	/*
1563 	 * Check the consistency of the self IDs we just read.  The
1564 	 * problem we face is that a new bus reset can start while we
1565 	 * read out the self IDs from the DMA buffer. If this happens,
1566 	 * the DMA buffer will be overwritten with new self IDs and we
1567 	 * will read out inconsistent data.  The OHCI specification
1568 	 * (section 11.2) recommends a technique similar to
1569 	 * linux/seqlock.h, where we remember the generation of the
1570 	 * self IDs in the buffer before reading them out and compare
1571 	 * it to the current generation after reading them out.  If
1572 	 * the two generations match we know we have a consistent set
1573 	 * of self IDs.
1574 	 */
1575 
1576 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1577 	if (new_generation != generation) {
1578 		fw_notify("recursive bus reset detected, "
1579 			  "discarding self ids\n");
1580 		return;
1581 	}
1582 
1583 	/* FIXME: Document how the locking works. */
1584 	spin_lock_irqsave(&ohci->lock, flags);
1585 
1586 	ohci->generation = generation;
1587 	context_stop(&ohci->at_request_ctx);
1588 	context_stop(&ohci->at_response_ctx);
1589 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1590 
1591 	if (ohci->quirks & QUIRK_RESET_PACKET)
1592 		ohci->request_generation = generation;
1593 
1594 	/*
1595 	 * This next bit is unrelated to the AT context stuff but we
1596 	 * have to do it under the spinlock also.  If a new config rom
1597 	 * was set up before this reset, the old one is now no longer
1598 	 * in use and we can free it. Update the config rom pointers
1599 	 * to point to the current config rom and clear the
1600 	 * next_config_rom pointer so a new update can take place.
1601 	 */
1602 
1603 	if (ohci->next_config_rom != NULL) {
1604 		if (ohci->next_config_rom != ohci->config_rom) {
1605 			free_rom      = ohci->config_rom;
1606 			free_rom_bus  = ohci->config_rom_bus;
1607 		}
1608 		ohci->config_rom      = ohci->next_config_rom;
1609 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
1610 		ohci->next_config_rom = NULL;
1611 
1612 		/*
1613 		 * Restore config_rom image and manually update
1614 		 * config_rom registers.  Writing the header quadlet
1615 		 * will indicate that the config rom is ready, so we
1616 		 * do that last.
1617 		 */
1618 		reg_write(ohci, OHCI1394_BusOptions,
1619 			  be32_to_cpu(ohci->config_rom[2]));
1620 		ohci->config_rom[0] = ohci->next_header;
1621 		reg_write(ohci, OHCI1394_ConfigROMhdr,
1622 			  be32_to_cpu(ohci->next_header));
1623 	}
1624 
1625 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1626 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1627 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1628 #endif
1629 
1630 	spin_unlock_irqrestore(&ohci->lock, flags);
1631 
1632 	if (free_rom)
1633 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1634 				  free_rom, free_rom_bus);
1635 
1636 	log_selfids(ohci->node_id, generation,
1637 		    self_id_count, ohci->self_id_buffer);
1638 
1639 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1640 				 self_id_count, ohci->self_id_buffer,
1641 				 ohci->csr_state_setclear_abdicate);
1642 	ohci->csr_state_setclear_abdicate = false;
1643 }
1644 
1645 static irqreturn_t irq_handler(int irq, void *data)
1646 {
1647 	struct fw_ohci *ohci = data;
1648 	u32 event, iso_event;
1649 	int i;
1650 
1651 	event = reg_read(ohci, OHCI1394_IntEventClear);
1652 
1653 	if (!event || !~event)
1654 		return IRQ_NONE;
1655 
1656 	/* busReset must not be cleared yet, see OHCI 1.1 clause 7.2.3.2 */
1657 	reg_write(ohci, OHCI1394_IntEventClear, event & ~OHCI1394_busReset);
1658 	log_irqs(event);
1659 
1660 	if (event & OHCI1394_selfIDComplete)
1661 		tasklet_schedule(&ohci->bus_reset_tasklet);
1662 
1663 	if (event & OHCI1394_RQPkt)
1664 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1665 
1666 	if (event & OHCI1394_RSPkt)
1667 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1668 
1669 	if (event & OHCI1394_reqTxComplete)
1670 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
1671 
1672 	if (event & OHCI1394_respTxComplete)
1673 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
1674 
1675 	iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1676 	reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1677 
1678 	while (iso_event) {
1679 		i = ffs(iso_event) - 1;
1680 		tasklet_schedule(&ohci->ir_context_list[i].context.tasklet);
1681 		iso_event &= ~(1 << i);
1682 	}
1683 
1684 	iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1685 	reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1686 
1687 	while (iso_event) {
1688 		i = ffs(iso_event) - 1;
1689 		tasklet_schedule(&ohci->it_context_list[i].context.tasklet);
1690 		iso_event &= ~(1 << i);
1691 	}
1692 
1693 	if (unlikely(event & OHCI1394_regAccessFail))
1694 		fw_error("Register access failure - "
1695 			 "please notify linux1394-devel@lists.sf.net\n");
1696 
1697 	if (unlikely(event & OHCI1394_postedWriteErr))
1698 		fw_error("PCI posted write error\n");
1699 
1700 	if (unlikely(event & OHCI1394_cycleTooLong)) {
1701 		if (printk_ratelimit())
1702 			fw_notify("isochronous cycle too long\n");
1703 		reg_write(ohci, OHCI1394_LinkControlSet,
1704 			  OHCI1394_LinkControl_cycleMaster);
1705 	}
1706 
1707 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
1708 		/*
1709 		 * We need to clear this event bit in order to make
1710 		 * cycleMatch isochronous I/O work.  In theory we should
1711 		 * stop active cycleMatch iso contexts now and restart
1712 		 * them at least two cycles later.  (FIXME?)
1713 		 */
1714 		if (printk_ratelimit())
1715 			fw_notify("isochronous cycle inconsistent\n");
1716 	}
1717 
1718 	if (event & OHCI1394_cycle64Seconds) {
1719 		spin_lock(&ohci->lock);
1720 		update_bus_time(ohci);
1721 		spin_unlock(&ohci->lock);
1722 	}
1723 
1724 	return IRQ_HANDLED;
1725 }
1726 
1727 static int software_reset(struct fw_ohci *ohci)
1728 {
1729 	int i;
1730 
1731 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1732 
1733 	for (i = 0; i < OHCI_LOOP_COUNT; i++) {
1734 		if ((reg_read(ohci, OHCI1394_HCControlSet) &
1735 		     OHCI1394_HCControl_softReset) == 0)
1736 			return 0;
1737 		msleep(1);
1738 	}
1739 
1740 	return -EBUSY;
1741 }
1742 
1743 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
1744 {
1745 	size_t size = length * 4;
1746 
1747 	memcpy(dest, src, size);
1748 	if (size < CONFIG_ROM_SIZE)
1749 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
1750 }
1751 
1752 static int configure_1394a_enhancements(struct fw_ohci *ohci)
1753 {
1754 	bool enable_1394a;
1755 	int ret, clear, set, offset;
1756 
1757 	/* Check if the driver should configure link and PHY. */
1758 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
1759 	      OHCI1394_HCControl_programPhyEnable))
1760 		return 0;
1761 
1762 	/* Paranoia: check whether the PHY supports 1394a, too. */
1763 	enable_1394a = false;
1764 	ret = read_phy_reg(ohci, 2);
1765 	if (ret < 0)
1766 		return ret;
1767 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
1768 		ret = read_paged_phy_reg(ohci, 1, 8);
1769 		if (ret < 0)
1770 			return ret;
1771 		if (ret >= 1)
1772 			enable_1394a = true;
1773 	}
1774 
1775 	if (ohci->quirks & QUIRK_NO_1394A)
1776 		enable_1394a = false;
1777 
1778 	/* Configure PHY and link consistently. */
1779 	if (enable_1394a) {
1780 		clear = 0;
1781 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
1782 	} else {
1783 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
1784 		set = 0;
1785 	}
1786 	ret = update_phy_reg(ohci, 5, clear, set);
1787 	if (ret < 0)
1788 		return ret;
1789 
1790 	if (enable_1394a)
1791 		offset = OHCI1394_HCControlSet;
1792 	else
1793 		offset = OHCI1394_HCControlClear;
1794 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
1795 
1796 	/* Clean up: configuration has been taken care of. */
1797 	reg_write(ohci, OHCI1394_HCControlClear,
1798 		  OHCI1394_HCControl_programPhyEnable);
1799 
1800 	return 0;
1801 }
1802 
1803 static int ohci_enable(struct fw_card *card,
1804 		       const __be32 *config_rom, size_t length)
1805 {
1806 	struct fw_ohci *ohci = fw_ohci(card);
1807 	struct pci_dev *dev = to_pci_dev(card->device);
1808 	u32 lps, seconds, version, irqs;
1809 	int i, ret;
1810 
1811 	if (software_reset(ohci)) {
1812 		fw_error("Failed to reset ohci card.\n");
1813 		return -EBUSY;
1814 	}
1815 
1816 	/*
1817 	 * Now enable LPS, which we need in order to start accessing
1818 	 * most of the registers.  In fact, on some cards (ALI M5251),
1819 	 * accessing registers in the SClk domain without LPS enabled
1820 	 * will lock up the machine.  Wait 50msec to make sure we have
1821 	 * full link enabled.  However, with some cards (well, at least
1822 	 * a JMicron PCIe card), we have to try again sometimes.
1823 	 */
1824 	reg_write(ohci, OHCI1394_HCControlSet,
1825 		  OHCI1394_HCControl_LPS |
1826 		  OHCI1394_HCControl_postedWriteEnable);
1827 	flush_writes(ohci);
1828 
1829 	for (lps = 0, i = 0; !lps && i < 3; i++) {
1830 		msleep(50);
1831 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
1832 		      OHCI1394_HCControl_LPS;
1833 	}
1834 
1835 	if (!lps) {
1836 		fw_error("Failed to set Link Power Status\n");
1837 		return -EIO;
1838 	}
1839 
1840 	reg_write(ohci, OHCI1394_HCControlClear,
1841 		  OHCI1394_HCControl_noByteSwapData);
1842 
1843 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
1844 	reg_write(ohci, OHCI1394_LinkControlSet,
1845 		  OHCI1394_LinkControl_rcvSelfID |
1846 		  OHCI1394_LinkControl_rcvPhyPkt |
1847 		  OHCI1394_LinkControl_cycleTimerEnable |
1848 		  OHCI1394_LinkControl_cycleMaster);
1849 
1850 	reg_write(ohci, OHCI1394_ATRetries,
1851 		  OHCI1394_MAX_AT_REQ_RETRIES |
1852 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
1853 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
1854 		  (200 << 16));
1855 
1856 	seconds = lower_32_bits(get_seconds());
1857 	reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
1858 	ohci->bus_time = seconds & ~0x3f;
1859 
1860 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
1861 	if (version >= OHCI_VERSION_1_1) {
1862 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
1863 			  0xfffffffe);
1864 		card->broadcast_channel_auto_allocated = true;
1865 	}
1866 
1867 	/* Get implemented bits of the priority arbitration request counter. */
1868 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
1869 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
1870 	reg_write(ohci, OHCI1394_FairnessControl, 0);
1871 	card->priority_budget_implemented = ohci->pri_req_max != 0;
1872 
1873 	ar_context_run(&ohci->ar_request_ctx);
1874 	ar_context_run(&ohci->ar_response_ctx);
1875 
1876 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
1877 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
1878 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
1879 
1880 	ret = configure_1394a_enhancements(ohci);
1881 	if (ret < 0)
1882 		return ret;
1883 
1884 	/* Activate link_on bit and contender bit in our self ID packets.*/
1885 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
1886 	if (ret < 0)
1887 		return ret;
1888 
1889 	/*
1890 	 * When the link is not yet enabled, the atomic config rom
1891 	 * update mechanism described below in ohci_set_config_rom()
1892 	 * is not active.  We have to update ConfigRomHeader and
1893 	 * BusOptions manually, and the write to ConfigROMmap takes
1894 	 * effect immediately.  We tie this to the enabling of the
1895 	 * link, so we have a valid config rom before enabling - the
1896 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
1897 	 * values before enabling.
1898 	 *
1899 	 * However, when the ConfigROMmap is written, some controllers
1900 	 * always read back quadlets 0 and 2 from the config rom to
1901 	 * the ConfigRomHeader and BusOptions registers on bus reset.
1902 	 * They shouldn't do that in this initial case where the link
1903 	 * isn't enabled.  This means we have to use the same
1904 	 * workaround here, setting the bus header to 0 and then write
1905 	 * the right values in the bus reset tasklet.
1906 	 */
1907 
1908 	if (config_rom) {
1909 		ohci->next_config_rom =
1910 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1911 					   &ohci->next_config_rom_bus,
1912 					   GFP_KERNEL);
1913 		if (ohci->next_config_rom == NULL)
1914 			return -ENOMEM;
1915 
1916 		copy_config_rom(ohci->next_config_rom, config_rom, length);
1917 	} else {
1918 		/*
1919 		 * In the suspend case, config_rom is NULL, which
1920 		 * means that we just reuse the old config rom.
1921 		 */
1922 		ohci->next_config_rom = ohci->config_rom;
1923 		ohci->next_config_rom_bus = ohci->config_rom_bus;
1924 	}
1925 
1926 	ohci->next_header = ohci->next_config_rom[0];
1927 	ohci->next_config_rom[0] = 0;
1928 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
1929 	reg_write(ohci, OHCI1394_BusOptions,
1930 		  be32_to_cpu(ohci->next_config_rom[2]));
1931 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
1932 
1933 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
1934 
1935 	if (!(ohci->quirks & QUIRK_NO_MSI))
1936 		pci_enable_msi(dev);
1937 	if (request_irq(dev->irq, irq_handler,
1938 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
1939 			ohci_driver_name, ohci)) {
1940 		fw_error("Failed to allocate interrupt %d.\n", dev->irq);
1941 		pci_disable_msi(dev);
1942 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1943 				  ohci->config_rom, ohci->config_rom_bus);
1944 		return -EIO;
1945 	}
1946 
1947 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
1948 		OHCI1394_RQPkt | OHCI1394_RSPkt |
1949 		OHCI1394_isochTx | OHCI1394_isochRx |
1950 		OHCI1394_postedWriteErr |
1951 		OHCI1394_selfIDComplete |
1952 		OHCI1394_regAccessFail |
1953 		OHCI1394_cycle64Seconds |
1954 		OHCI1394_cycleInconsistent | OHCI1394_cycleTooLong |
1955 		OHCI1394_masterIntEnable;
1956 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
1957 		irqs |= OHCI1394_busReset;
1958 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
1959 
1960 	reg_write(ohci, OHCI1394_HCControlSet,
1961 		  OHCI1394_HCControl_linkEnable |
1962 		  OHCI1394_HCControl_BIBimageValid);
1963 	flush_writes(ohci);
1964 
1965 	/* We are ready to go, reset bus to finish initialization. */
1966 	fw_schedule_bus_reset(&ohci->card, false, true);
1967 
1968 	return 0;
1969 }
1970 
1971 static int ohci_set_config_rom(struct fw_card *card,
1972 			       const __be32 *config_rom, size_t length)
1973 {
1974 	struct fw_ohci *ohci;
1975 	unsigned long flags;
1976 	int ret = -EBUSY;
1977 	__be32 *next_config_rom;
1978 	dma_addr_t uninitialized_var(next_config_rom_bus);
1979 
1980 	ohci = fw_ohci(card);
1981 
1982 	/*
1983 	 * When the OHCI controller is enabled, the config rom update
1984 	 * mechanism is a bit tricky, but easy enough to use.  See
1985 	 * section 5.5.6 in the OHCI specification.
1986 	 *
1987 	 * The OHCI controller caches the new config rom address in a
1988 	 * shadow register (ConfigROMmapNext) and needs a bus reset
1989 	 * for the changes to take place.  When the bus reset is
1990 	 * detected, the controller loads the new values for the
1991 	 * ConfigRomHeader and BusOptions registers from the specified
1992 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
1993 	 * shadow register. All automatically and atomically.
1994 	 *
1995 	 * Now, there's a twist to this story.  The automatic load of
1996 	 * ConfigRomHeader and BusOptions doesn't honor the
1997 	 * noByteSwapData bit, so with a be32 config rom, the
1998 	 * controller will load be32 values in to these registers
1999 	 * during the atomic update, even on litte endian
2000 	 * architectures.  The workaround we use is to put a 0 in the
2001 	 * header quadlet; 0 is endian agnostic and means that the
2002 	 * config rom isn't ready yet.  In the bus reset tasklet we
2003 	 * then set up the real values for the two registers.
2004 	 *
2005 	 * We use ohci->lock to avoid racing with the code that sets
2006 	 * ohci->next_config_rom to NULL (see bus_reset_tasklet).
2007 	 */
2008 
2009 	next_config_rom =
2010 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2011 				   &next_config_rom_bus, GFP_KERNEL);
2012 	if (next_config_rom == NULL)
2013 		return -ENOMEM;
2014 
2015 	spin_lock_irqsave(&ohci->lock, flags);
2016 
2017 	if (ohci->next_config_rom == NULL) {
2018 		ohci->next_config_rom = next_config_rom;
2019 		ohci->next_config_rom_bus = next_config_rom_bus;
2020 
2021 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2022 
2023 		ohci->next_header = config_rom[0];
2024 		ohci->next_config_rom[0] = 0;
2025 
2026 		reg_write(ohci, OHCI1394_ConfigROMmap,
2027 			  ohci->next_config_rom_bus);
2028 		ret = 0;
2029 	}
2030 
2031 	spin_unlock_irqrestore(&ohci->lock, flags);
2032 
2033 	/*
2034 	 * Now initiate a bus reset to have the changes take
2035 	 * effect. We clean up the old config rom memory and DMA
2036 	 * mappings in the bus reset tasklet, since the OHCI
2037 	 * controller could need to access it before the bus reset
2038 	 * takes effect.
2039 	 */
2040 	if (ret == 0)
2041 		fw_schedule_bus_reset(&ohci->card, true, true);
2042 	else
2043 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2044 				  next_config_rom, next_config_rom_bus);
2045 
2046 	return ret;
2047 }
2048 
2049 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2050 {
2051 	struct fw_ohci *ohci = fw_ohci(card);
2052 
2053 	at_context_transmit(&ohci->at_request_ctx, packet);
2054 }
2055 
2056 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2057 {
2058 	struct fw_ohci *ohci = fw_ohci(card);
2059 
2060 	at_context_transmit(&ohci->at_response_ctx, packet);
2061 }
2062 
2063 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2064 {
2065 	struct fw_ohci *ohci = fw_ohci(card);
2066 	struct context *ctx = &ohci->at_request_ctx;
2067 	struct driver_data *driver_data = packet->driver_data;
2068 	int ret = -ENOENT;
2069 
2070 	tasklet_disable(&ctx->tasklet);
2071 
2072 	if (packet->ack != 0)
2073 		goto out;
2074 
2075 	if (packet->payload_mapped)
2076 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2077 				 packet->payload_length, DMA_TO_DEVICE);
2078 
2079 	log_ar_at_event('T', packet->speed, packet->header, 0x20);
2080 	driver_data->packet = NULL;
2081 	packet->ack = RCODE_CANCELLED;
2082 	packet->callback(packet, &ohci->card, packet->ack);
2083 	ret = 0;
2084  out:
2085 	tasklet_enable(&ctx->tasklet);
2086 
2087 	return ret;
2088 }
2089 
2090 static int ohci_enable_phys_dma(struct fw_card *card,
2091 				int node_id, int generation)
2092 {
2093 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2094 	return 0;
2095 #else
2096 	struct fw_ohci *ohci = fw_ohci(card);
2097 	unsigned long flags;
2098 	int n, ret = 0;
2099 
2100 	/*
2101 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2102 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2103 	 */
2104 
2105 	spin_lock_irqsave(&ohci->lock, flags);
2106 
2107 	if (ohci->generation != generation) {
2108 		ret = -ESTALE;
2109 		goto out;
2110 	}
2111 
2112 	/*
2113 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2114 	 * enabled for _all_ nodes on remote buses.
2115 	 */
2116 
2117 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2118 	if (n < 32)
2119 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2120 	else
2121 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2122 
2123 	flush_writes(ohci);
2124  out:
2125 	spin_unlock_irqrestore(&ohci->lock, flags);
2126 
2127 	return ret;
2128 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2129 }
2130 
2131 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2132 {
2133 	struct fw_ohci *ohci = fw_ohci(card);
2134 	unsigned long flags;
2135 	u32 value;
2136 
2137 	switch (csr_offset) {
2138 	case CSR_STATE_CLEAR:
2139 	case CSR_STATE_SET:
2140 		if (ohci->is_root &&
2141 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2142 		     OHCI1394_LinkControl_cycleMaster))
2143 			value = CSR_STATE_BIT_CMSTR;
2144 		else
2145 			value = 0;
2146 		if (ohci->csr_state_setclear_abdicate)
2147 			value |= CSR_STATE_BIT_ABDICATE;
2148 
2149 		return value;
2150 
2151 	case CSR_NODE_IDS:
2152 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2153 
2154 	case CSR_CYCLE_TIME:
2155 		return get_cycle_time(ohci);
2156 
2157 	case CSR_BUS_TIME:
2158 		/*
2159 		 * We might be called just after the cycle timer has wrapped
2160 		 * around but just before the cycle64Seconds handler, so we
2161 		 * better check here, too, if the bus time needs to be updated.
2162 		 */
2163 		spin_lock_irqsave(&ohci->lock, flags);
2164 		value = update_bus_time(ohci);
2165 		spin_unlock_irqrestore(&ohci->lock, flags);
2166 		return value;
2167 
2168 	case CSR_BUSY_TIMEOUT:
2169 		value = reg_read(ohci, OHCI1394_ATRetries);
2170 		return (value >> 4) & 0x0ffff00f;
2171 
2172 	case CSR_PRIORITY_BUDGET:
2173 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2174 			(ohci->pri_req_max << 8);
2175 
2176 	default:
2177 		WARN_ON(1);
2178 		return 0;
2179 	}
2180 }
2181 
2182 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2183 {
2184 	struct fw_ohci *ohci = fw_ohci(card);
2185 	unsigned long flags;
2186 
2187 	switch (csr_offset) {
2188 	case CSR_STATE_CLEAR:
2189 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2190 			reg_write(ohci, OHCI1394_LinkControlClear,
2191 				  OHCI1394_LinkControl_cycleMaster);
2192 			flush_writes(ohci);
2193 		}
2194 		if (value & CSR_STATE_BIT_ABDICATE)
2195 			ohci->csr_state_setclear_abdicate = false;
2196 		break;
2197 
2198 	case CSR_STATE_SET:
2199 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2200 			reg_write(ohci, OHCI1394_LinkControlSet,
2201 				  OHCI1394_LinkControl_cycleMaster);
2202 			flush_writes(ohci);
2203 		}
2204 		if (value & CSR_STATE_BIT_ABDICATE)
2205 			ohci->csr_state_setclear_abdicate = true;
2206 		break;
2207 
2208 	case CSR_NODE_IDS:
2209 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2210 		flush_writes(ohci);
2211 		break;
2212 
2213 	case CSR_CYCLE_TIME:
2214 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2215 		reg_write(ohci, OHCI1394_IntEventSet,
2216 			  OHCI1394_cycleInconsistent);
2217 		flush_writes(ohci);
2218 		break;
2219 
2220 	case CSR_BUS_TIME:
2221 		spin_lock_irqsave(&ohci->lock, flags);
2222 		ohci->bus_time = (ohci->bus_time & 0x7f) | (value & ~0x7f);
2223 		spin_unlock_irqrestore(&ohci->lock, flags);
2224 		break;
2225 
2226 	case CSR_BUSY_TIMEOUT:
2227 		value = (value & 0xf) | ((value & 0xf) << 4) |
2228 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2229 		reg_write(ohci, OHCI1394_ATRetries, value);
2230 		flush_writes(ohci);
2231 		break;
2232 
2233 	case CSR_PRIORITY_BUDGET:
2234 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2235 		flush_writes(ohci);
2236 		break;
2237 
2238 	default:
2239 		WARN_ON(1);
2240 		break;
2241 	}
2242 }
2243 
2244 static void copy_iso_headers(struct iso_context *ctx, void *p)
2245 {
2246 	int i = ctx->header_length;
2247 
2248 	if (i + ctx->base.header_size > PAGE_SIZE)
2249 		return;
2250 
2251 	/*
2252 	 * The iso header is byteswapped to little endian by
2253 	 * the controller, but the remaining header quadlets
2254 	 * are big endian.  We want to present all the headers
2255 	 * as big endian, so we have to swap the first quadlet.
2256 	 */
2257 	if (ctx->base.header_size > 0)
2258 		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
2259 	if (ctx->base.header_size > 4)
2260 		*(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
2261 	if (ctx->base.header_size > 8)
2262 		memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
2263 	ctx->header_length += ctx->base.header_size;
2264 }
2265 
2266 static int handle_ir_packet_per_buffer(struct context *context,
2267 				       struct descriptor *d,
2268 				       struct descriptor *last)
2269 {
2270 	struct iso_context *ctx =
2271 		container_of(context, struct iso_context, context);
2272 	struct descriptor *pd;
2273 	__le32 *ir_header;
2274 	void *p;
2275 
2276 	for (pd = d; pd <= last; pd++)
2277 		if (pd->transfer_status)
2278 			break;
2279 	if (pd > last)
2280 		/* Descriptor(s) not done yet, stop iteration */
2281 		return 0;
2282 
2283 	p = last + 1;
2284 	copy_iso_headers(ctx, p);
2285 
2286 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2287 		ir_header = (__le32 *) p;
2288 		ctx->base.callback.sc(&ctx->base,
2289 				      le32_to_cpu(ir_header[0]) & 0xffff,
2290 				      ctx->header_length, ctx->header,
2291 				      ctx->base.callback_data);
2292 		ctx->header_length = 0;
2293 	}
2294 
2295 	return 1;
2296 }
2297 
2298 /* d == last because each descriptor block is only a single descriptor. */
2299 static int handle_ir_buffer_fill(struct context *context,
2300 				 struct descriptor *d,
2301 				 struct descriptor *last)
2302 {
2303 	struct iso_context *ctx =
2304 		container_of(context, struct iso_context, context);
2305 
2306 	if (!last->transfer_status)
2307 		/* Descriptor(s) not done yet, stop iteration */
2308 		return 0;
2309 
2310 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS)
2311 		ctx->base.callback.mc(&ctx->base,
2312 				      le32_to_cpu(last->data_address) +
2313 				      le16_to_cpu(last->req_count) -
2314 				      le16_to_cpu(last->res_count),
2315 				      ctx->base.callback_data);
2316 
2317 	return 1;
2318 }
2319 
2320 static int handle_it_packet(struct context *context,
2321 			    struct descriptor *d,
2322 			    struct descriptor *last)
2323 {
2324 	struct iso_context *ctx =
2325 		container_of(context, struct iso_context, context);
2326 	int i;
2327 	struct descriptor *pd;
2328 
2329 	for (pd = d; pd <= last; pd++)
2330 		if (pd->transfer_status)
2331 			break;
2332 	if (pd > last)
2333 		/* Descriptor(s) not done yet, stop iteration */
2334 		return 0;
2335 
2336 	i = ctx->header_length;
2337 	if (i + 4 < PAGE_SIZE) {
2338 		/* Present this value as big-endian to match the receive code */
2339 		*(__be32 *)(ctx->header + i) = cpu_to_be32(
2340 				((u32)le16_to_cpu(pd->transfer_status) << 16) |
2341 				le16_to_cpu(pd->res_count));
2342 		ctx->header_length += 4;
2343 	}
2344 	if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2345 		ctx->base.callback.sc(&ctx->base, le16_to_cpu(last->res_count),
2346 				      ctx->header_length, ctx->header,
2347 				      ctx->base.callback_data);
2348 		ctx->header_length = 0;
2349 	}
2350 	return 1;
2351 }
2352 
2353 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2354 {
2355 	u32 hi = channels >> 32, lo = channels;
2356 
2357 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2358 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2359 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2360 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2361 	mmiowb();
2362 	ohci->mc_channels = channels;
2363 }
2364 
2365 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2366 				int type, int channel, size_t header_size)
2367 {
2368 	struct fw_ohci *ohci = fw_ohci(card);
2369 	struct iso_context *uninitialized_var(ctx);
2370 	descriptor_callback_t uninitialized_var(callback);
2371 	u64 *uninitialized_var(channels);
2372 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2373 	unsigned long flags;
2374 	int index, ret = -EBUSY;
2375 
2376 	spin_lock_irqsave(&ohci->lock, flags);
2377 
2378 	switch (type) {
2379 	case FW_ISO_CONTEXT_TRANSMIT:
2380 		mask     = &ohci->it_context_mask;
2381 		callback = handle_it_packet;
2382 		index    = ffs(*mask) - 1;
2383 		if (index >= 0) {
2384 			*mask &= ~(1 << index);
2385 			regs = OHCI1394_IsoXmitContextBase(index);
2386 			ctx  = &ohci->it_context_list[index];
2387 		}
2388 		break;
2389 
2390 	case FW_ISO_CONTEXT_RECEIVE:
2391 		channels = &ohci->ir_context_channels;
2392 		mask     = &ohci->ir_context_mask;
2393 		callback = handle_ir_packet_per_buffer;
2394 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2395 		if (index >= 0) {
2396 			*channels &= ~(1ULL << channel);
2397 			*mask     &= ~(1 << index);
2398 			regs = OHCI1394_IsoRcvContextBase(index);
2399 			ctx  = &ohci->ir_context_list[index];
2400 		}
2401 		break;
2402 
2403 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2404 		mask     = &ohci->ir_context_mask;
2405 		callback = handle_ir_buffer_fill;
2406 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2407 		if (index >= 0) {
2408 			ohci->mc_allocated = true;
2409 			*mask &= ~(1 << index);
2410 			regs = OHCI1394_IsoRcvContextBase(index);
2411 			ctx  = &ohci->ir_context_list[index];
2412 		}
2413 		break;
2414 
2415 	default:
2416 		index = -1;
2417 		ret = -ENOSYS;
2418 	}
2419 
2420 	spin_unlock_irqrestore(&ohci->lock, flags);
2421 
2422 	if (index < 0)
2423 		return ERR_PTR(ret);
2424 
2425 	memset(ctx, 0, sizeof(*ctx));
2426 	ctx->header_length = 0;
2427 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
2428 	if (ctx->header == NULL) {
2429 		ret = -ENOMEM;
2430 		goto out;
2431 	}
2432 	ret = context_init(&ctx->context, ohci, regs, callback);
2433 	if (ret < 0)
2434 		goto out_with_header;
2435 
2436 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
2437 		set_multichannel_mask(ohci, 0);
2438 
2439 	return &ctx->base;
2440 
2441  out_with_header:
2442 	free_page((unsigned long)ctx->header);
2443  out:
2444 	spin_lock_irqsave(&ohci->lock, flags);
2445 
2446 	switch (type) {
2447 	case FW_ISO_CONTEXT_RECEIVE:
2448 		*channels |= 1ULL << channel;
2449 		break;
2450 
2451 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2452 		ohci->mc_allocated = false;
2453 		break;
2454 	}
2455 	*mask |= 1 << index;
2456 
2457 	spin_unlock_irqrestore(&ohci->lock, flags);
2458 
2459 	return ERR_PTR(ret);
2460 }
2461 
2462 static int ohci_start_iso(struct fw_iso_context *base,
2463 			  s32 cycle, u32 sync, u32 tags)
2464 {
2465 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2466 	struct fw_ohci *ohci = ctx->context.ohci;
2467 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2468 	int index;
2469 
2470 	switch (ctx->base.type) {
2471 	case FW_ISO_CONTEXT_TRANSMIT:
2472 		index = ctx - ohci->it_context_list;
2473 		match = 0;
2474 		if (cycle >= 0)
2475 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
2476 				(cycle & 0x7fff) << 16;
2477 
2478 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
2479 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
2480 		context_run(&ctx->context, match);
2481 		break;
2482 
2483 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2484 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
2485 		/* fall through */
2486 	case FW_ISO_CONTEXT_RECEIVE:
2487 		index = ctx - ohci->ir_context_list;
2488 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
2489 		if (cycle >= 0) {
2490 			match |= (cycle & 0x07fff) << 12;
2491 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
2492 		}
2493 
2494 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2495 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2496 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2497 		context_run(&ctx->context, control);
2498 		break;
2499 	}
2500 
2501 	return 0;
2502 }
2503 
2504 static int ohci_stop_iso(struct fw_iso_context *base)
2505 {
2506 	struct fw_ohci *ohci = fw_ohci(base->card);
2507 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2508 	int index;
2509 
2510 	switch (ctx->base.type) {
2511 	case FW_ISO_CONTEXT_TRANSMIT:
2512 		index = ctx - ohci->it_context_list;
2513 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2514 		break;
2515 
2516 	case FW_ISO_CONTEXT_RECEIVE:
2517 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2518 		index = ctx - ohci->ir_context_list;
2519 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2520 		break;
2521 	}
2522 	flush_writes(ohci);
2523 	context_stop(&ctx->context);
2524 
2525 	return 0;
2526 }
2527 
2528 static void ohci_free_iso_context(struct fw_iso_context *base)
2529 {
2530 	struct fw_ohci *ohci = fw_ohci(base->card);
2531 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2532 	unsigned long flags;
2533 	int index;
2534 
2535 	ohci_stop_iso(base);
2536 	context_release(&ctx->context);
2537 	free_page((unsigned long)ctx->header);
2538 
2539 	spin_lock_irqsave(&ohci->lock, flags);
2540 
2541 	switch (base->type) {
2542 	case FW_ISO_CONTEXT_TRANSMIT:
2543 		index = ctx - ohci->it_context_list;
2544 		ohci->it_context_mask |= 1 << index;
2545 		break;
2546 
2547 	case FW_ISO_CONTEXT_RECEIVE:
2548 		index = ctx - ohci->ir_context_list;
2549 		ohci->ir_context_mask |= 1 << index;
2550 		ohci->ir_context_channels |= 1ULL << base->channel;
2551 		break;
2552 
2553 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2554 		index = ctx - ohci->ir_context_list;
2555 		ohci->ir_context_mask |= 1 << index;
2556 		ohci->ir_context_channels |= ohci->mc_channels;
2557 		ohci->mc_channels = 0;
2558 		ohci->mc_allocated = false;
2559 		break;
2560 	}
2561 
2562 	spin_unlock_irqrestore(&ohci->lock, flags);
2563 }
2564 
2565 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
2566 {
2567 	struct fw_ohci *ohci = fw_ohci(base->card);
2568 	unsigned long flags;
2569 	int ret;
2570 
2571 	switch (base->type) {
2572 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2573 
2574 		spin_lock_irqsave(&ohci->lock, flags);
2575 
2576 		/* Don't allow multichannel to grab other contexts' channels. */
2577 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
2578 			*channels = ohci->ir_context_channels;
2579 			ret = -EBUSY;
2580 		} else {
2581 			set_multichannel_mask(ohci, *channels);
2582 			ret = 0;
2583 		}
2584 
2585 		spin_unlock_irqrestore(&ohci->lock, flags);
2586 
2587 		break;
2588 	default:
2589 		ret = -EINVAL;
2590 	}
2591 
2592 	return ret;
2593 }
2594 
2595 static int queue_iso_transmit(struct iso_context *ctx,
2596 			      struct fw_iso_packet *packet,
2597 			      struct fw_iso_buffer *buffer,
2598 			      unsigned long payload)
2599 {
2600 	struct descriptor *d, *last, *pd;
2601 	struct fw_iso_packet *p;
2602 	__le32 *header;
2603 	dma_addr_t d_bus, page_bus;
2604 	u32 z, header_z, payload_z, irq;
2605 	u32 payload_index, payload_end_index, next_page_index;
2606 	int page, end_page, i, length, offset;
2607 
2608 	p = packet;
2609 	payload_index = payload;
2610 
2611 	if (p->skip)
2612 		z = 1;
2613 	else
2614 		z = 2;
2615 	if (p->header_length > 0)
2616 		z++;
2617 
2618 	/* Determine the first page the payload isn't contained in. */
2619 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2620 	if (p->payload_length > 0)
2621 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
2622 	else
2623 		payload_z = 0;
2624 
2625 	z += payload_z;
2626 
2627 	/* Get header size in number of descriptors. */
2628 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2629 
2630 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2631 	if (d == NULL)
2632 		return -ENOMEM;
2633 
2634 	if (!p->skip) {
2635 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2636 		d[0].req_count = cpu_to_le16(8);
2637 		/*
2638 		 * Link the skip address to this descriptor itself.  This causes
2639 		 * a context to skip a cycle whenever lost cycles or FIFO
2640 		 * overruns occur, without dropping the data.  The application
2641 		 * should then decide whether this is an error condition or not.
2642 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
2643 		 */
2644 		d[0].branch_address = cpu_to_le32(d_bus | z);
2645 
2646 		header = (__le32 *) &d[1];
2647 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2648 					IT_HEADER_TAG(p->tag) |
2649 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2650 					IT_HEADER_CHANNEL(ctx->base.channel) |
2651 					IT_HEADER_SPEED(ctx->base.speed));
2652 		header[1] =
2653 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2654 							  p->payload_length));
2655 	}
2656 
2657 	if (p->header_length > 0) {
2658 		d[2].req_count    = cpu_to_le16(p->header_length);
2659 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2660 		memcpy(&d[z], p->header, p->header_length);
2661 	}
2662 
2663 	pd = d + z - payload_z;
2664 	payload_end_index = payload_index + p->payload_length;
2665 	for (i = 0; i < payload_z; i++) {
2666 		page               = payload_index >> PAGE_SHIFT;
2667 		offset             = payload_index & ~PAGE_MASK;
2668 		next_page_index    = (page + 1) << PAGE_SHIFT;
2669 		length             =
2670 			min(next_page_index, payload_end_index) - payload_index;
2671 		pd[i].req_count    = cpu_to_le16(length);
2672 
2673 		page_bus = page_private(buffer->pages[page]);
2674 		pd[i].data_address = cpu_to_le32(page_bus + offset);
2675 
2676 		payload_index += length;
2677 	}
2678 
2679 	if (p->interrupt)
2680 		irq = DESCRIPTOR_IRQ_ALWAYS;
2681 	else
2682 		irq = DESCRIPTOR_NO_IRQ;
2683 
2684 	last = z == 2 ? d : d + z - 1;
2685 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2686 				     DESCRIPTOR_STATUS |
2687 				     DESCRIPTOR_BRANCH_ALWAYS |
2688 				     irq);
2689 
2690 	context_append(&ctx->context, d, z, header_z);
2691 
2692 	return 0;
2693 }
2694 
2695 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
2696 				       struct fw_iso_packet *packet,
2697 				       struct fw_iso_buffer *buffer,
2698 				       unsigned long payload)
2699 {
2700 	struct descriptor *d, *pd;
2701 	dma_addr_t d_bus, page_bus;
2702 	u32 z, header_z, rest;
2703 	int i, j, length;
2704 	int page, offset, packet_count, header_size, payload_per_buffer;
2705 
2706 	/*
2707 	 * The OHCI controller puts the isochronous header and trailer in the
2708 	 * buffer, so we need at least 8 bytes.
2709 	 */
2710 	packet_count = packet->header_length / ctx->base.header_size;
2711 	header_size  = max(ctx->base.header_size, (size_t)8);
2712 
2713 	/* Get header size in number of descriptors. */
2714 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
2715 	page     = payload >> PAGE_SHIFT;
2716 	offset   = payload & ~PAGE_MASK;
2717 	payload_per_buffer = packet->payload_length / packet_count;
2718 
2719 	for (i = 0; i < packet_count; i++) {
2720 		/* d points to the header descriptor */
2721 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
2722 		d = context_get_descriptors(&ctx->context,
2723 				z + header_z, &d_bus);
2724 		if (d == NULL)
2725 			return -ENOMEM;
2726 
2727 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
2728 					      DESCRIPTOR_INPUT_MORE);
2729 		if (packet->skip && i == 0)
2730 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2731 		d->req_count    = cpu_to_le16(header_size);
2732 		d->res_count    = d->req_count;
2733 		d->transfer_status = 0;
2734 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
2735 
2736 		rest = payload_per_buffer;
2737 		pd = d;
2738 		for (j = 1; j < z; j++) {
2739 			pd++;
2740 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2741 						  DESCRIPTOR_INPUT_MORE);
2742 
2743 			if (offset + rest < PAGE_SIZE)
2744 				length = rest;
2745 			else
2746 				length = PAGE_SIZE - offset;
2747 			pd->req_count = cpu_to_le16(length);
2748 			pd->res_count = pd->req_count;
2749 			pd->transfer_status = 0;
2750 
2751 			page_bus = page_private(buffer->pages[page]);
2752 			pd->data_address = cpu_to_le32(page_bus + offset);
2753 
2754 			offset = (offset + length) & ~PAGE_MASK;
2755 			rest -= length;
2756 			if (offset == 0)
2757 				page++;
2758 		}
2759 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
2760 					  DESCRIPTOR_INPUT_LAST |
2761 					  DESCRIPTOR_BRANCH_ALWAYS);
2762 		if (packet->interrupt && i == packet_count - 1)
2763 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2764 
2765 		context_append(&ctx->context, d, z, header_z);
2766 	}
2767 
2768 	return 0;
2769 }
2770 
2771 static int queue_iso_buffer_fill(struct iso_context *ctx,
2772 				 struct fw_iso_packet *packet,
2773 				 struct fw_iso_buffer *buffer,
2774 				 unsigned long payload)
2775 {
2776 	struct descriptor *d;
2777 	dma_addr_t d_bus, page_bus;
2778 	int page, offset, rest, z, i, length;
2779 
2780 	page   = payload >> PAGE_SHIFT;
2781 	offset = payload & ~PAGE_MASK;
2782 	rest   = packet->payload_length;
2783 
2784 	/* We need one descriptor for each page in the buffer. */
2785 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
2786 
2787 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
2788 		return -EFAULT;
2789 
2790 	for (i = 0; i < z; i++) {
2791 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
2792 		if (d == NULL)
2793 			return -ENOMEM;
2794 
2795 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
2796 					 DESCRIPTOR_BRANCH_ALWAYS);
2797 		if (packet->skip && i == 0)
2798 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
2799 		if (packet->interrupt && i == z - 1)
2800 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
2801 
2802 		if (offset + rest < PAGE_SIZE)
2803 			length = rest;
2804 		else
2805 			length = PAGE_SIZE - offset;
2806 		d->req_count = cpu_to_le16(length);
2807 		d->res_count = d->req_count;
2808 		d->transfer_status = 0;
2809 
2810 		page_bus = page_private(buffer->pages[page]);
2811 		d->data_address = cpu_to_le32(page_bus + offset);
2812 
2813 		rest -= length;
2814 		offset = 0;
2815 		page++;
2816 
2817 		context_append(&ctx->context, d, 1, 0);
2818 	}
2819 
2820 	return 0;
2821 }
2822 
2823 static int ohci_queue_iso(struct fw_iso_context *base,
2824 			  struct fw_iso_packet *packet,
2825 			  struct fw_iso_buffer *buffer,
2826 			  unsigned long payload)
2827 {
2828 	struct iso_context *ctx = container_of(base, struct iso_context, base);
2829 	unsigned long flags;
2830 	int ret = -ENOSYS;
2831 
2832 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
2833 	switch (base->type) {
2834 	case FW_ISO_CONTEXT_TRANSMIT:
2835 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
2836 		break;
2837 	case FW_ISO_CONTEXT_RECEIVE:
2838 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
2839 		break;
2840 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2841 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
2842 		break;
2843 	}
2844 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
2845 
2846 	return ret;
2847 }
2848 
2849 static const struct fw_card_driver ohci_driver = {
2850 	.enable			= ohci_enable,
2851 	.read_phy_reg		= ohci_read_phy_reg,
2852 	.update_phy_reg		= ohci_update_phy_reg,
2853 	.set_config_rom		= ohci_set_config_rom,
2854 	.send_request		= ohci_send_request,
2855 	.send_response		= ohci_send_response,
2856 	.cancel_packet		= ohci_cancel_packet,
2857 	.enable_phys_dma	= ohci_enable_phys_dma,
2858 	.read_csr		= ohci_read_csr,
2859 	.write_csr		= ohci_write_csr,
2860 
2861 	.allocate_iso_context	= ohci_allocate_iso_context,
2862 	.free_iso_context	= ohci_free_iso_context,
2863 	.set_iso_channels	= ohci_set_iso_channels,
2864 	.queue_iso		= ohci_queue_iso,
2865 	.start_iso		= ohci_start_iso,
2866 	.stop_iso		= ohci_stop_iso,
2867 };
2868 
2869 #ifdef CONFIG_PPC_PMAC
2870 static void pmac_ohci_on(struct pci_dev *dev)
2871 {
2872 	if (machine_is(powermac)) {
2873 		struct device_node *ofn = pci_device_to_OF_node(dev);
2874 
2875 		if (ofn) {
2876 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
2877 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
2878 		}
2879 	}
2880 }
2881 
2882 static void pmac_ohci_off(struct pci_dev *dev)
2883 {
2884 	if (machine_is(powermac)) {
2885 		struct device_node *ofn = pci_device_to_OF_node(dev);
2886 
2887 		if (ofn) {
2888 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
2889 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
2890 		}
2891 	}
2892 }
2893 #else
2894 static inline void pmac_ohci_on(struct pci_dev *dev) {}
2895 static inline void pmac_ohci_off(struct pci_dev *dev) {}
2896 #endif /* CONFIG_PPC_PMAC */
2897 
2898 static int __devinit pci_probe(struct pci_dev *dev,
2899 			       const struct pci_device_id *ent)
2900 {
2901 	struct fw_ohci *ohci;
2902 	u32 bus_options, max_receive, link_speed, version;
2903 	u64 guid;
2904 	int i, err, n_ir, n_it;
2905 	size_t size;
2906 
2907 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
2908 	if (ohci == NULL) {
2909 		err = -ENOMEM;
2910 		goto fail;
2911 	}
2912 
2913 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
2914 
2915 	pmac_ohci_on(dev);
2916 
2917 	err = pci_enable_device(dev);
2918 	if (err) {
2919 		fw_error("Failed to enable OHCI hardware\n");
2920 		goto fail_free;
2921 	}
2922 
2923 	pci_set_master(dev);
2924 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
2925 	pci_set_drvdata(dev, ohci);
2926 
2927 	spin_lock_init(&ohci->lock);
2928 	mutex_init(&ohci->phy_reg_mutex);
2929 
2930 	tasklet_init(&ohci->bus_reset_tasklet,
2931 		     bus_reset_tasklet, (unsigned long)ohci);
2932 
2933 	err = pci_request_region(dev, 0, ohci_driver_name);
2934 	if (err) {
2935 		fw_error("MMIO resource unavailable\n");
2936 		goto fail_disable;
2937 	}
2938 
2939 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
2940 	if (ohci->registers == NULL) {
2941 		fw_error("Failed to remap registers\n");
2942 		err = -ENXIO;
2943 		goto fail_iomem;
2944 	}
2945 
2946 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
2947 		if ((ohci_quirks[i].vendor == dev->vendor) &&
2948 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
2949 		     ohci_quirks[i].device == dev->device) &&
2950 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
2951 		     ohci_quirks[i].revision >= dev->revision)) {
2952 			ohci->quirks = ohci_quirks[i].flags;
2953 			break;
2954 		}
2955 	if (param_quirks)
2956 		ohci->quirks = param_quirks;
2957 
2958 	ar_context_init(&ohci->ar_request_ctx, ohci,
2959 			OHCI1394_AsReqRcvContextControlSet);
2960 
2961 	ar_context_init(&ohci->ar_response_ctx, ohci,
2962 			OHCI1394_AsRspRcvContextControlSet);
2963 
2964 	context_init(&ohci->at_request_ctx, ohci,
2965 		     OHCI1394_AsReqTrContextControlSet, handle_at_packet);
2966 
2967 	context_init(&ohci->at_response_ctx, ohci,
2968 		     OHCI1394_AsRspTrContextControlSet, handle_at_packet);
2969 
2970 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
2971 	ohci->ir_context_channels = ~0ULL;
2972 	ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
2973 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
2974 	n_ir = hweight32(ohci->ir_context_mask);
2975 	size = sizeof(struct iso_context) * n_ir;
2976 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
2977 
2978 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
2979 	ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
2980 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
2981 	n_it = hweight32(ohci->it_context_mask);
2982 	size = sizeof(struct iso_context) * n_it;
2983 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
2984 
2985 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
2986 		err = -ENOMEM;
2987 		goto fail_contexts;
2988 	}
2989 
2990 	/* self-id dma buffer allocation */
2991 	ohci->self_id_cpu = dma_alloc_coherent(ohci->card.device,
2992 					       SELF_ID_BUF_SIZE,
2993 					       &ohci->self_id_bus,
2994 					       GFP_KERNEL);
2995 	if (ohci->self_id_cpu == NULL) {
2996 		err = -ENOMEM;
2997 		goto fail_contexts;
2998 	}
2999 
3000 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3001 	max_receive = (bus_options >> 12) & 0xf;
3002 	link_speed = bus_options & 0x7;
3003 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3004 		reg_read(ohci, OHCI1394_GUIDLo);
3005 
3006 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3007 	if (err)
3008 		goto fail_self_id;
3009 
3010 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3011 	fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
3012 		  "%d IR + %d IT contexts, quirks 0x%x\n",
3013 		  dev_name(&dev->dev), version >> 16, version & 0xff,
3014 		  n_ir, n_it, ohci->quirks);
3015 
3016 	return 0;
3017 
3018  fail_self_id:
3019 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
3020 			  ohci->self_id_cpu, ohci->self_id_bus);
3021  fail_contexts:
3022 	kfree(ohci->ir_context_list);
3023 	kfree(ohci->it_context_list);
3024 	context_release(&ohci->at_response_ctx);
3025 	context_release(&ohci->at_request_ctx);
3026 	ar_context_release(&ohci->ar_response_ctx);
3027 	ar_context_release(&ohci->ar_request_ctx);
3028 	pci_iounmap(dev, ohci->registers);
3029  fail_iomem:
3030 	pci_release_region(dev, 0);
3031  fail_disable:
3032 	pci_disable_device(dev);
3033  fail_free:
3034 	kfree(&ohci->card);
3035 	pmac_ohci_off(dev);
3036  fail:
3037 	if (err == -ENOMEM)
3038 		fw_error("Out of memory\n");
3039 
3040 	return err;
3041 }
3042 
3043 static void pci_remove(struct pci_dev *dev)
3044 {
3045 	struct fw_ohci *ohci;
3046 
3047 	ohci = pci_get_drvdata(dev);
3048 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3049 	flush_writes(ohci);
3050 	fw_core_remove_card(&ohci->card);
3051 
3052 	/*
3053 	 * FIXME: Fail all pending packets here, now that the upper
3054 	 * layers can't queue any more.
3055 	 */
3056 
3057 	software_reset(ohci);
3058 	free_irq(dev->irq, ohci);
3059 
3060 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3061 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3062 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3063 	if (ohci->config_rom)
3064 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3065 				  ohci->config_rom, ohci->config_rom_bus);
3066 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
3067 			  ohci->self_id_cpu, ohci->self_id_bus);
3068 	ar_context_release(&ohci->ar_request_ctx);
3069 	ar_context_release(&ohci->ar_response_ctx);
3070 	context_release(&ohci->at_request_ctx);
3071 	context_release(&ohci->at_response_ctx);
3072 	kfree(ohci->it_context_list);
3073 	kfree(ohci->ir_context_list);
3074 	pci_disable_msi(dev);
3075 	pci_iounmap(dev, ohci->registers);
3076 	pci_release_region(dev, 0);
3077 	pci_disable_device(dev);
3078 	kfree(&ohci->card);
3079 	pmac_ohci_off(dev);
3080 
3081 	fw_notify("Removed fw-ohci device.\n");
3082 }
3083 
3084 #ifdef CONFIG_PM
3085 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3086 {
3087 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3088 	int err;
3089 
3090 	software_reset(ohci);
3091 	free_irq(dev->irq, ohci);
3092 	pci_disable_msi(dev);
3093 	err = pci_save_state(dev);
3094 	if (err) {
3095 		fw_error("pci_save_state failed\n");
3096 		return err;
3097 	}
3098 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3099 	if (err)
3100 		fw_error("pci_set_power_state failed with %d\n", err);
3101 	pmac_ohci_off(dev);
3102 
3103 	return 0;
3104 }
3105 
3106 static int pci_resume(struct pci_dev *dev)
3107 {
3108 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3109 	int err;
3110 
3111 	pmac_ohci_on(dev);
3112 	pci_set_power_state(dev, PCI_D0);
3113 	pci_restore_state(dev);
3114 	err = pci_enable_device(dev);
3115 	if (err) {
3116 		fw_error("pci_enable_device failed\n");
3117 		return err;
3118 	}
3119 
3120 	return ohci_enable(&ohci->card, NULL, 0);
3121 }
3122 #endif
3123 
3124 static const struct pci_device_id pci_table[] = {
3125 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3126 	{ }
3127 };
3128 
3129 MODULE_DEVICE_TABLE(pci, pci_table);
3130 
3131 static struct pci_driver fw_ohci_pci_driver = {
3132 	.name		= ohci_driver_name,
3133 	.id_table	= pci_table,
3134 	.probe		= pci_probe,
3135 	.remove		= pci_remove,
3136 #ifdef CONFIG_PM
3137 	.resume		= pci_resume,
3138 	.suspend	= pci_suspend,
3139 #endif
3140 };
3141 
3142 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3143 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3144 MODULE_LICENSE("GPL");
3145 
3146 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3147 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3148 MODULE_ALIAS("ohci1394");
3149 #endif
3150 
3151 static int __init fw_ohci_init(void)
3152 {
3153 	return pci_register_driver(&fw_ohci_pci_driver);
3154 }
3155 
3156 static void __exit fw_ohci_cleanup(void)
3157 {
3158 	pci_unregister_driver(&fw_ohci_pci_driver);
3159 }
3160 
3161 module_init(fw_ohci_init);
3162 module_exit(fw_ohci_cleanup);
3163