xref: /openbmc/linux/drivers/firewire/ohci.c (revision 80ecbd24)
1 /*
2  * Driver for OHCI 1394 controllers
3  *
4  * Copyright (C) 2003-2006 Kristian Hoegsberg <krh@bitplanet.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20 
21 #include <linux/bitops.h>
22 #include <linux/bug.h>
23 #include <linux/compiler.h>
24 #include <linux/delay.h>
25 #include <linux/device.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/firewire.h>
28 #include <linux/firewire-constants.h>
29 #include <linux/init.h>
30 #include <linux/interrupt.h>
31 #include <linux/io.h>
32 #include <linux/kernel.h>
33 #include <linux/list.h>
34 #include <linux/mm.h>
35 #include <linux/module.h>
36 #include <linux/moduleparam.h>
37 #include <linux/mutex.h>
38 #include <linux/pci.h>
39 #include <linux/pci_ids.h>
40 #include <linux/slab.h>
41 #include <linux/spinlock.h>
42 #include <linux/string.h>
43 #include <linux/time.h>
44 #include <linux/vmalloc.h>
45 #include <linux/workqueue.h>
46 
47 #include <asm/byteorder.h>
48 #include <asm/page.h>
49 
50 #ifdef CONFIG_PPC_PMAC
51 #include <asm/pmac_feature.h>
52 #endif
53 
54 #include "core.h"
55 #include "ohci.h"
56 
57 #define ohci_info(ohci, f, args...)	dev_info(ohci->card.device, f, ##args)
58 #define ohci_notice(ohci, f, args...)	dev_notice(ohci->card.device, f, ##args)
59 #define ohci_err(ohci, f, args...)	dev_err(ohci->card.device, f, ##args)
60 
61 #define DESCRIPTOR_OUTPUT_MORE		0
62 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
63 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
64 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
65 #define DESCRIPTOR_STATUS		(1 << 11)
66 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
67 #define DESCRIPTOR_PING			(1 << 7)
68 #define DESCRIPTOR_YY			(1 << 6)
69 #define DESCRIPTOR_NO_IRQ		(0 << 4)
70 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
71 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
72 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
73 #define DESCRIPTOR_WAIT			(3 << 0)
74 
75 #define DESCRIPTOR_CMD			(0xf << 12)
76 
77 struct descriptor {
78 	__le16 req_count;
79 	__le16 control;
80 	__le32 data_address;
81 	__le32 branch_address;
82 	__le16 res_count;
83 	__le16 transfer_status;
84 } __attribute__((aligned(16)));
85 
86 #define CONTROL_SET(regs)	(regs)
87 #define CONTROL_CLEAR(regs)	((regs) + 4)
88 #define COMMAND_PTR(regs)	((regs) + 12)
89 #define CONTEXT_MATCH(regs)	((regs) + 16)
90 
91 #define AR_BUFFER_SIZE	(32*1024)
92 #define AR_BUFFERS_MIN	DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
93 /* we need at least two pages for proper list management */
94 #define AR_BUFFERS	(AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)
95 
96 #define MAX_ASYNC_PAYLOAD	4096
97 #define MAX_AR_PACKET_SIZE	(16 + MAX_ASYNC_PAYLOAD + 4)
98 #define AR_WRAPAROUND_PAGES	DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)
99 
100 struct ar_context {
101 	struct fw_ohci *ohci;
102 	struct page *pages[AR_BUFFERS];
103 	void *buffer;
104 	struct descriptor *descriptors;
105 	dma_addr_t descriptors_bus;
106 	void *pointer;
107 	unsigned int last_buffer_index;
108 	u32 regs;
109 	struct tasklet_struct tasklet;
110 };
111 
112 struct context;
113 
114 typedef int (*descriptor_callback_t)(struct context *ctx,
115 				     struct descriptor *d,
116 				     struct descriptor *last);
117 
118 /*
119  * A buffer that contains a block of DMA-able coherent memory used for
120  * storing a portion of a DMA descriptor program.
121  */
122 struct descriptor_buffer {
123 	struct list_head list;
124 	dma_addr_t buffer_bus;
125 	size_t buffer_size;
126 	size_t used;
127 	struct descriptor buffer[0];
128 };
129 
130 struct context {
131 	struct fw_ohci *ohci;
132 	u32 regs;
133 	int total_allocation;
134 	u32 current_bus;
135 	bool running;
136 	bool flushing;
137 
138 	/*
139 	 * List of page-sized buffers for storing DMA descriptors.
140 	 * Head of list contains buffers in use and tail of list contains
141 	 * free buffers.
142 	 */
143 	struct list_head buffer_list;
144 
145 	/*
146 	 * Pointer to a buffer inside buffer_list that contains the tail
147 	 * end of the current DMA program.
148 	 */
149 	struct descriptor_buffer *buffer_tail;
150 
151 	/*
152 	 * The descriptor containing the branch address of the first
153 	 * descriptor that has not yet been filled by the device.
154 	 */
155 	struct descriptor *last;
156 
157 	/*
158 	 * The last descriptor block in the DMA program. It contains the branch
159 	 * address that must be updated upon appending a new descriptor.
160 	 */
161 	struct descriptor *prev;
162 	int prev_z;
163 
164 	descriptor_callback_t callback;
165 
166 	struct tasklet_struct tasklet;
167 };
168 
169 #define IT_HEADER_SY(v)          ((v) <<  0)
170 #define IT_HEADER_TCODE(v)       ((v) <<  4)
171 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
172 #define IT_HEADER_TAG(v)         ((v) << 14)
173 #define IT_HEADER_SPEED(v)       ((v) << 16)
174 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
175 
176 struct iso_context {
177 	struct fw_iso_context base;
178 	struct context context;
179 	void *header;
180 	size_t header_length;
181 	unsigned long flushing_completions;
182 	u32 mc_buffer_bus;
183 	u16 mc_completed;
184 	u16 last_timestamp;
185 	u8 sync;
186 	u8 tags;
187 };
188 
189 #define CONFIG_ROM_SIZE 1024
190 
191 struct fw_ohci {
192 	struct fw_card card;
193 
194 	__iomem char *registers;
195 	int node_id;
196 	int generation;
197 	int request_generation;	/* for timestamping incoming requests */
198 	unsigned quirks;
199 	unsigned int pri_req_max;
200 	u32 bus_time;
201 	bool bus_time_running;
202 	bool is_root;
203 	bool csr_state_setclear_abdicate;
204 	int n_ir;
205 	int n_it;
206 	/*
207 	 * Spinlock for accessing fw_ohci data.  Never call out of
208 	 * this driver with this lock held.
209 	 */
210 	spinlock_t lock;
211 
212 	struct mutex phy_reg_mutex;
213 
214 	void *misc_buffer;
215 	dma_addr_t misc_buffer_bus;
216 
217 	struct ar_context ar_request_ctx;
218 	struct ar_context ar_response_ctx;
219 	struct context at_request_ctx;
220 	struct context at_response_ctx;
221 
222 	u32 it_context_support;
223 	u32 it_context_mask;     /* unoccupied IT contexts */
224 	struct iso_context *it_context_list;
225 	u64 ir_context_channels; /* unoccupied channels */
226 	u32 ir_context_support;
227 	u32 ir_context_mask;     /* unoccupied IR contexts */
228 	struct iso_context *ir_context_list;
229 	u64 mc_channels; /* channels in use by the multichannel IR context */
230 	bool mc_allocated;
231 
232 	__be32    *config_rom;
233 	dma_addr_t config_rom_bus;
234 	__be32    *next_config_rom;
235 	dma_addr_t next_config_rom_bus;
236 	__be32     next_header;
237 
238 	__le32    *self_id_cpu;
239 	dma_addr_t self_id_bus;
240 	struct work_struct bus_reset_work;
241 
242 	u32 self_id_buffer[512];
243 };
244 
245 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
246 {
247 	return container_of(card, struct fw_ohci, card);
248 }
249 
250 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
251 #define IR_CONTEXT_BUFFER_FILL		0x80000000
252 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
253 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
254 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
255 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
256 
257 #define CONTEXT_RUN	0x8000
258 #define CONTEXT_WAKE	0x1000
259 #define CONTEXT_DEAD	0x0800
260 #define CONTEXT_ACTIVE	0x0400
261 
262 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
263 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
264 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
265 
266 #define OHCI1394_REGISTER_SIZE		0x800
267 #define OHCI1394_PCI_HCI_Control	0x40
268 #define SELF_ID_BUF_SIZE		0x800
269 #define OHCI_TCODE_PHY_PACKET		0x0e
270 #define OHCI_VERSION_1_1		0x010010
271 
272 static char ohci_driver_name[] = KBUILD_MODNAME;
273 
274 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
275 #define PCI_DEVICE_ID_CREATIVE_SB1394	0x4001
276 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
277 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
278 #define PCI_DEVICE_ID_TI_TSB12LV26	0x8020
279 #define PCI_DEVICE_ID_TI_TSB82AA2	0x8025
280 #define PCI_DEVICE_ID_VIA_VT630X	0x3044
281 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
282 #define PCI_REV_ID_VIA_VT6306		0x46
283 
284 #define QUIRK_CYCLE_TIMER		1
285 #define QUIRK_RESET_PACKET		2
286 #define QUIRK_BE_HEADERS		4
287 #define QUIRK_NO_1394A			8
288 #define QUIRK_NO_MSI			16
289 #define QUIRK_TI_SLLZ059		32
290 #define QUIRK_IR_WAKE			64
291 #define QUIRK_PHY_LCTRL_TIMEOUT		128
292 
293 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
294 static const struct {
295 	unsigned short vendor, device, revision, flags;
296 } ohci_quirks[] = {
297 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
298 		QUIRK_CYCLE_TIMER},
299 
300 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
301 		QUIRK_BE_HEADERS},
302 
303 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
304 		QUIRK_PHY_LCTRL_TIMEOUT | QUIRK_NO_MSI},
305 
306 	{PCI_VENDOR_ID_ATT, PCI_ANY_ID, PCI_ANY_ID,
307 		QUIRK_PHY_LCTRL_TIMEOUT},
308 
309 	{PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
310 		QUIRK_RESET_PACKET},
311 
312 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
313 		QUIRK_NO_MSI},
314 
315 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
316 		QUIRK_CYCLE_TIMER},
317 
318 	{PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
319 		QUIRK_NO_MSI},
320 
321 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
322 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
323 
324 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
325 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
326 
327 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
328 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
329 
330 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
331 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
332 
333 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
334 		QUIRK_RESET_PACKET},
335 
336 	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT630X, PCI_REV_ID_VIA_VT6306,
337 		QUIRK_CYCLE_TIMER | QUIRK_IR_WAKE},
338 
339 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
340 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
341 };
342 
343 /* This overrides anything that was found in ohci_quirks[]. */
344 static int param_quirks;
345 module_param_named(quirks, param_quirks, int, 0644);
346 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
347 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
348 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
349 	", AR/selfID endianness = "	__stringify(QUIRK_BE_HEADERS)
350 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
351 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
352 	", TI SLLZ059 erratum = "	__stringify(QUIRK_TI_SLLZ059)
353 	", IR wake unreliable = "	__stringify(QUIRK_IR_WAKE)
354 	", phy LCtrl timeout = "	__stringify(QUIRK_PHY_LCTRL_TIMEOUT)
355 	")");
356 
357 #define OHCI_PARAM_DEBUG_AT_AR		1
358 #define OHCI_PARAM_DEBUG_SELFIDS	2
359 #define OHCI_PARAM_DEBUG_IRQS		4
360 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
361 
362 static int param_debug;
363 module_param_named(debug, param_debug, int, 0644);
364 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
365 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
366 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
367 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
368 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
369 	", or a combination, or all = -1)");
370 
371 static void log_irqs(struct fw_ohci *ohci, u32 evt)
372 {
373 	if (likely(!(param_debug &
374 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
375 		return;
376 
377 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
378 	    !(evt & OHCI1394_busReset))
379 		return;
380 
381 	ohci_notice(ohci, "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
382 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
383 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
384 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
385 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
386 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
387 	    evt & OHCI1394_isochRx		? " IR"			: "",
388 	    evt & OHCI1394_isochTx		? " IT"			: "",
389 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
390 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
391 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
392 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
393 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
394 	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
395 	    evt & OHCI1394_busReset		? " busReset"		: "",
396 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
397 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
398 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
399 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
400 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
401 		    OHCI1394_cycleInconsistent |
402 		    OHCI1394_regAccessFail | OHCI1394_busReset)
403 						? " ?"			: "");
404 }
405 
406 static const char *speed[] = {
407 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
408 };
409 static const char *power[] = {
410 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
411 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
412 };
413 static const char port[] = { '.', '-', 'p', 'c', };
414 
415 static char _p(u32 *s, int shift)
416 {
417 	return port[*s >> shift & 3];
418 }
419 
420 static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
421 {
422 	u32 *s;
423 
424 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
425 		return;
426 
427 	ohci_notice(ohci, "%d selfIDs, generation %d, local node ID %04x\n",
428 		    self_id_count, generation, ohci->node_id);
429 
430 	for (s = ohci->self_id_buffer; self_id_count--; ++s)
431 		if ((*s & 1 << 23) == 0)
432 			ohci_notice(ohci,
433 			    "selfID 0: %08x, phy %d [%c%c%c] %s gc=%d %s %s%s%s\n",
434 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
435 			    speed[*s >> 14 & 3], *s >> 16 & 63,
436 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
437 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
438 		else
439 			ohci_notice(ohci,
440 			    "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
441 			    *s, *s >> 24 & 63,
442 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
443 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
444 }
445 
446 static const char *evts[] = {
447 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
448 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
449 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
450 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
451 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
452 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
453 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
454 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
455 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
456 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
457 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
458 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
459 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
460 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
461 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
462 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
463 	[0x20] = "pending/cancelled",
464 };
465 static const char *tcodes[] = {
466 	[0x0] = "QW req",		[0x1] = "BW req",
467 	[0x2] = "W resp",		[0x3] = "-reserved-",
468 	[0x4] = "QR req",		[0x5] = "BR req",
469 	[0x6] = "QR resp",		[0x7] = "BR resp",
470 	[0x8] = "cycle start",		[0x9] = "Lk req",
471 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
472 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
473 	[0xe] = "link internal",	[0xf] = "-reserved-",
474 };
475 
476 static void log_ar_at_event(struct fw_ohci *ohci,
477 			    char dir, int speed, u32 *header, int evt)
478 {
479 	int tcode = header[0] >> 4 & 0xf;
480 	char specific[12];
481 
482 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
483 		return;
484 
485 	if (unlikely(evt >= ARRAY_SIZE(evts)))
486 			evt = 0x1f;
487 
488 	if (evt == OHCI1394_evt_bus_reset) {
489 		ohci_notice(ohci, "A%c evt_bus_reset, generation %d\n",
490 			    dir, (header[2] >> 16) & 0xff);
491 		return;
492 	}
493 
494 	switch (tcode) {
495 	case 0x0: case 0x6: case 0x8:
496 		snprintf(specific, sizeof(specific), " = %08x",
497 			 be32_to_cpu((__force __be32)header[3]));
498 		break;
499 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
500 		snprintf(specific, sizeof(specific), " %x,%x",
501 			 header[3] >> 16, header[3] & 0xffff);
502 		break;
503 	default:
504 		specific[0] = '\0';
505 	}
506 
507 	switch (tcode) {
508 	case 0xa:
509 		ohci_notice(ohci, "A%c %s, %s\n",
510 			    dir, evts[evt], tcodes[tcode]);
511 		break;
512 	case 0xe:
513 		ohci_notice(ohci, "A%c %s, PHY %08x %08x\n",
514 			    dir, evts[evt], header[1], header[2]);
515 		break;
516 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
517 		ohci_notice(ohci,
518 			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s, %04x%08x%s\n",
519 			    dir, speed, header[0] >> 10 & 0x3f,
520 			    header[1] >> 16, header[0] >> 16, evts[evt],
521 			    tcodes[tcode], header[1] & 0xffff, header[2], specific);
522 		break;
523 	default:
524 		ohci_notice(ohci,
525 			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s%s\n",
526 			    dir, speed, header[0] >> 10 & 0x3f,
527 			    header[1] >> 16, header[0] >> 16, evts[evt],
528 			    tcodes[tcode], specific);
529 	}
530 }
531 
532 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
533 {
534 	writel(data, ohci->registers + offset);
535 }
536 
537 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
538 {
539 	return readl(ohci->registers + offset);
540 }
541 
542 static inline void flush_writes(const struct fw_ohci *ohci)
543 {
544 	/* Do a dummy read to flush writes. */
545 	reg_read(ohci, OHCI1394_Version);
546 }
547 
548 /*
549  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
550  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
551  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
552  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
553  */
554 static int read_phy_reg(struct fw_ohci *ohci, int addr)
555 {
556 	u32 val;
557 	int i;
558 
559 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
560 	for (i = 0; i < 3 + 100; i++) {
561 		val = reg_read(ohci, OHCI1394_PhyControl);
562 		if (!~val)
563 			return -ENODEV; /* Card was ejected. */
564 
565 		if (val & OHCI1394_PhyControl_ReadDone)
566 			return OHCI1394_PhyControl_ReadData(val);
567 
568 		/*
569 		 * Try a few times without waiting.  Sleeping is necessary
570 		 * only when the link/PHY interface is busy.
571 		 */
572 		if (i >= 3)
573 			msleep(1);
574 	}
575 	ohci_err(ohci, "failed to read phy reg %d\n", addr);
576 	dump_stack();
577 
578 	return -EBUSY;
579 }
580 
581 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
582 {
583 	int i;
584 
585 	reg_write(ohci, OHCI1394_PhyControl,
586 		  OHCI1394_PhyControl_Write(addr, val));
587 	for (i = 0; i < 3 + 100; i++) {
588 		val = reg_read(ohci, OHCI1394_PhyControl);
589 		if (!~val)
590 			return -ENODEV; /* Card was ejected. */
591 
592 		if (!(val & OHCI1394_PhyControl_WritePending))
593 			return 0;
594 
595 		if (i >= 3)
596 			msleep(1);
597 	}
598 	ohci_err(ohci, "failed to write phy reg %d, val %u\n", addr, val);
599 	dump_stack();
600 
601 	return -EBUSY;
602 }
603 
604 static int update_phy_reg(struct fw_ohci *ohci, int addr,
605 			  int clear_bits, int set_bits)
606 {
607 	int ret = read_phy_reg(ohci, addr);
608 	if (ret < 0)
609 		return ret;
610 
611 	/*
612 	 * The interrupt status bits are cleared by writing a one bit.
613 	 * Avoid clearing them unless explicitly requested in set_bits.
614 	 */
615 	if (addr == 5)
616 		clear_bits |= PHY_INT_STATUS_BITS;
617 
618 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
619 }
620 
621 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
622 {
623 	int ret;
624 
625 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
626 	if (ret < 0)
627 		return ret;
628 
629 	return read_phy_reg(ohci, addr);
630 }
631 
632 static int ohci_read_phy_reg(struct fw_card *card, int addr)
633 {
634 	struct fw_ohci *ohci = fw_ohci(card);
635 	int ret;
636 
637 	mutex_lock(&ohci->phy_reg_mutex);
638 	ret = read_phy_reg(ohci, addr);
639 	mutex_unlock(&ohci->phy_reg_mutex);
640 
641 	return ret;
642 }
643 
644 static int ohci_update_phy_reg(struct fw_card *card, int addr,
645 			       int clear_bits, int set_bits)
646 {
647 	struct fw_ohci *ohci = fw_ohci(card);
648 	int ret;
649 
650 	mutex_lock(&ohci->phy_reg_mutex);
651 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
652 	mutex_unlock(&ohci->phy_reg_mutex);
653 
654 	return ret;
655 }
656 
657 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
658 {
659 	return page_private(ctx->pages[i]);
660 }
661 
662 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
663 {
664 	struct descriptor *d;
665 
666 	d = &ctx->descriptors[index];
667 	d->branch_address  &= cpu_to_le32(~0xf);
668 	d->res_count       =  cpu_to_le16(PAGE_SIZE);
669 	d->transfer_status =  0;
670 
671 	wmb(); /* finish init of new descriptors before branch_address update */
672 	d = &ctx->descriptors[ctx->last_buffer_index];
673 	d->branch_address  |= cpu_to_le32(1);
674 
675 	ctx->last_buffer_index = index;
676 
677 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
678 }
679 
680 static void ar_context_release(struct ar_context *ctx)
681 {
682 	unsigned int i;
683 
684 	if (ctx->buffer)
685 		vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
686 
687 	for (i = 0; i < AR_BUFFERS; i++)
688 		if (ctx->pages[i]) {
689 			dma_unmap_page(ctx->ohci->card.device,
690 				       ar_buffer_bus(ctx, i),
691 				       PAGE_SIZE, DMA_FROM_DEVICE);
692 			__free_page(ctx->pages[i]);
693 		}
694 }
695 
696 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
697 {
698 	struct fw_ohci *ohci = ctx->ohci;
699 
700 	if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
701 		reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
702 		flush_writes(ohci);
703 
704 		ohci_err(ohci, "AR error: %s; DMA stopped\n", error_msg);
705 	}
706 	/* FIXME: restart? */
707 }
708 
709 static inline unsigned int ar_next_buffer_index(unsigned int index)
710 {
711 	return (index + 1) % AR_BUFFERS;
712 }
713 
714 static inline unsigned int ar_prev_buffer_index(unsigned int index)
715 {
716 	return (index - 1 + AR_BUFFERS) % AR_BUFFERS;
717 }
718 
719 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
720 {
721 	return ar_next_buffer_index(ctx->last_buffer_index);
722 }
723 
724 /*
725  * We search for the buffer that contains the last AR packet DMA data written
726  * by the controller.
727  */
728 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
729 						 unsigned int *buffer_offset)
730 {
731 	unsigned int i, next_i, last = ctx->last_buffer_index;
732 	__le16 res_count, next_res_count;
733 
734 	i = ar_first_buffer_index(ctx);
735 	res_count = ACCESS_ONCE(ctx->descriptors[i].res_count);
736 
737 	/* A buffer that is not yet completely filled must be the last one. */
738 	while (i != last && res_count == 0) {
739 
740 		/* Peek at the next descriptor. */
741 		next_i = ar_next_buffer_index(i);
742 		rmb(); /* read descriptors in order */
743 		next_res_count = ACCESS_ONCE(
744 				ctx->descriptors[next_i].res_count);
745 		/*
746 		 * If the next descriptor is still empty, we must stop at this
747 		 * descriptor.
748 		 */
749 		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
750 			/*
751 			 * The exception is when the DMA data for one packet is
752 			 * split over three buffers; in this case, the middle
753 			 * buffer's descriptor might be never updated by the
754 			 * controller and look still empty, and we have to peek
755 			 * at the third one.
756 			 */
757 			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
758 				next_i = ar_next_buffer_index(next_i);
759 				rmb();
760 				next_res_count = ACCESS_ONCE(
761 					ctx->descriptors[next_i].res_count);
762 				if (next_res_count != cpu_to_le16(PAGE_SIZE))
763 					goto next_buffer_is_active;
764 			}
765 
766 			break;
767 		}
768 
769 next_buffer_is_active:
770 		i = next_i;
771 		res_count = next_res_count;
772 	}
773 
774 	rmb(); /* read res_count before the DMA data */
775 
776 	*buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
777 	if (*buffer_offset > PAGE_SIZE) {
778 		*buffer_offset = 0;
779 		ar_context_abort(ctx, "corrupted descriptor");
780 	}
781 
782 	return i;
783 }
784 
785 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
786 				    unsigned int end_buffer_index,
787 				    unsigned int end_buffer_offset)
788 {
789 	unsigned int i;
790 
791 	i = ar_first_buffer_index(ctx);
792 	while (i != end_buffer_index) {
793 		dma_sync_single_for_cpu(ctx->ohci->card.device,
794 					ar_buffer_bus(ctx, i),
795 					PAGE_SIZE, DMA_FROM_DEVICE);
796 		i = ar_next_buffer_index(i);
797 	}
798 	if (end_buffer_offset > 0)
799 		dma_sync_single_for_cpu(ctx->ohci->card.device,
800 					ar_buffer_bus(ctx, i),
801 					end_buffer_offset, DMA_FROM_DEVICE);
802 }
803 
804 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
805 #define cond_le32_to_cpu(v) \
806 	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
807 #else
808 #define cond_le32_to_cpu(v) le32_to_cpu(v)
809 #endif
810 
811 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
812 {
813 	struct fw_ohci *ohci = ctx->ohci;
814 	struct fw_packet p;
815 	u32 status, length, tcode;
816 	int evt;
817 
818 	p.header[0] = cond_le32_to_cpu(buffer[0]);
819 	p.header[1] = cond_le32_to_cpu(buffer[1]);
820 	p.header[2] = cond_le32_to_cpu(buffer[2]);
821 
822 	tcode = (p.header[0] >> 4) & 0x0f;
823 	switch (tcode) {
824 	case TCODE_WRITE_QUADLET_REQUEST:
825 	case TCODE_READ_QUADLET_RESPONSE:
826 		p.header[3] = (__force __u32) buffer[3];
827 		p.header_length = 16;
828 		p.payload_length = 0;
829 		break;
830 
831 	case TCODE_READ_BLOCK_REQUEST :
832 		p.header[3] = cond_le32_to_cpu(buffer[3]);
833 		p.header_length = 16;
834 		p.payload_length = 0;
835 		break;
836 
837 	case TCODE_WRITE_BLOCK_REQUEST:
838 	case TCODE_READ_BLOCK_RESPONSE:
839 	case TCODE_LOCK_REQUEST:
840 	case TCODE_LOCK_RESPONSE:
841 		p.header[3] = cond_le32_to_cpu(buffer[3]);
842 		p.header_length = 16;
843 		p.payload_length = p.header[3] >> 16;
844 		if (p.payload_length > MAX_ASYNC_PAYLOAD) {
845 			ar_context_abort(ctx, "invalid packet length");
846 			return NULL;
847 		}
848 		break;
849 
850 	case TCODE_WRITE_RESPONSE:
851 	case TCODE_READ_QUADLET_REQUEST:
852 	case OHCI_TCODE_PHY_PACKET:
853 		p.header_length = 12;
854 		p.payload_length = 0;
855 		break;
856 
857 	default:
858 		ar_context_abort(ctx, "invalid tcode");
859 		return NULL;
860 	}
861 
862 	p.payload = (void *) buffer + p.header_length;
863 
864 	/* FIXME: What to do about evt_* errors? */
865 	length = (p.header_length + p.payload_length + 3) / 4;
866 	status = cond_le32_to_cpu(buffer[length]);
867 	evt    = (status >> 16) & 0x1f;
868 
869 	p.ack        = evt - 16;
870 	p.speed      = (status >> 21) & 0x7;
871 	p.timestamp  = status & 0xffff;
872 	p.generation = ohci->request_generation;
873 
874 	log_ar_at_event(ohci, 'R', p.speed, p.header, evt);
875 
876 	/*
877 	 * Several controllers, notably from NEC and VIA, forget to
878 	 * write ack_complete status at PHY packet reception.
879 	 */
880 	if (evt == OHCI1394_evt_no_status &&
881 	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
882 		p.ack = ACK_COMPLETE;
883 
884 	/*
885 	 * The OHCI bus reset handler synthesizes a PHY packet with
886 	 * the new generation number when a bus reset happens (see
887 	 * section 8.4.2.3).  This helps us determine when a request
888 	 * was received and make sure we send the response in the same
889 	 * generation.  We only need this for requests; for responses
890 	 * we use the unique tlabel for finding the matching
891 	 * request.
892 	 *
893 	 * Alas some chips sometimes emit bus reset packets with a
894 	 * wrong generation.  We set the correct generation for these
895 	 * at a slightly incorrect time (in bus_reset_work).
896 	 */
897 	if (evt == OHCI1394_evt_bus_reset) {
898 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
899 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
900 	} else if (ctx == &ohci->ar_request_ctx) {
901 		fw_core_handle_request(&ohci->card, &p);
902 	} else {
903 		fw_core_handle_response(&ohci->card, &p);
904 	}
905 
906 	return buffer + length + 1;
907 }
908 
909 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
910 {
911 	void *next;
912 
913 	while (p < end) {
914 		next = handle_ar_packet(ctx, p);
915 		if (!next)
916 			return p;
917 		p = next;
918 	}
919 
920 	return p;
921 }
922 
923 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
924 {
925 	unsigned int i;
926 
927 	i = ar_first_buffer_index(ctx);
928 	while (i != end_buffer) {
929 		dma_sync_single_for_device(ctx->ohci->card.device,
930 					   ar_buffer_bus(ctx, i),
931 					   PAGE_SIZE, DMA_FROM_DEVICE);
932 		ar_context_link_page(ctx, i);
933 		i = ar_next_buffer_index(i);
934 	}
935 }
936 
937 static void ar_context_tasklet(unsigned long data)
938 {
939 	struct ar_context *ctx = (struct ar_context *)data;
940 	unsigned int end_buffer_index, end_buffer_offset;
941 	void *p, *end;
942 
943 	p = ctx->pointer;
944 	if (!p)
945 		return;
946 
947 	end_buffer_index = ar_search_last_active_buffer(ctx,
948 							&end_buffer_offset);
949 	ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
950 	end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
951 
952 	if (end_buffer_index < ar_first_buffer_index(ctx)) {
953 		/*
954 		 * The filled part of the overall buffer wraps around; handle
955 		 * all packets up to the buffer end here.  If the last packet
956 		 * wraps around, its tail will be visible after the buffer end
957 		 * because the buffer start pages are mapped there again.
958 		 */
959 		void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
960 		p = handle_ar_packets(ctx, p, buffer_end);
961 		if (p < buffer_end)
962 			goto error;
963 		/* adjust p to point back into the actual buffer */
964 		p -= AR_BUFFERS * PAGE_SIZE;
965 	}
966 
967 	p = handle_ar_packets(ctx, p, end);
968 	if (p != end) {
969 		if (p > end)
970 			ar_context_abort(ctx, "inconsistent descriptor");
971 		goto error;
972 	}
973 
974 	ctx->pointer = p;
975 	ar_recycle_buffers(ctx, end_buffer_index);
976 
977 	return;
978 
979 error:
980 	ctx->pointer = NULL;
981 }
982 
983 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
984 			   unsigned int descriptors_offset, u32 regs)
985 {
986 	unsigned int i;
987 	dma_addr_t dma_addr;
988 	struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
989 	struct descriptor *d;
990 
991 	ctx->regs        = regs;
992 	ctx->ohci        = ohci;
993 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
994 
995 	for (i = 0; i < AR_BUFFERS; i++) {
996 		ctx->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32);
997 		if (!ctx->pages[i])
998 			goto out_of_memory;
999 		dma_addr = dma_map_page(ohci->card.device, ctx->pages[i],
1000 					0, PAGE_SIZE, DMA_FROM_DEVICE);
1001 		if (dma_mapping_error(ohci->card.device, dma_addr)) {
1002 			__free_page(ctx->pages[i]);
1003 			ctx->pages[i] = NULL;
1004 			goto out_of_memory;
1005 		}
1006 		set_page_private(ctx->pages[i], dma_addr);
1007 	}
1008 
1009 	for (i = 0; i < AR_BUFFERS; i++)
1010 		pages[i]              = ctx->pages[i];
1011 	for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
1012 		pages[AR_BUFFERS + i] = ctx->pages[i];
1013 	ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
1014 				 -1, PAGE_KERNEL);
1015 	if (!ctx->buffer)
1016 		goto out_of_memory;
1017 
1018 	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
1019 	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
1020 
1021 	for (i = 0; i < AR_BUFFERS; i++) {
1022 		d = &ctx->descriptors[i];
1023 		d->req_count      = cpu_to_le16(PAGE_SIZE);
1024 		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
1025 						DESCRIPTOR_STATUS |
1026 						DESCRIPTOR_BRANCH_ALWAYS);
1027 		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
1028 		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
1029 			ar_next_buffer_index(i) * sizeof(struct descriptor));
1030 	}
1031 
1032 	return 0;
1033 
1034 out_of_memory:
1035 	ar_context_release(ctx);
1036 
1037 	return -ENOMEM;
1038 }
1039 
1040 static void ar_context_run(struct ar_context *ctx)
1041 {
1042 	unsigned int i;
1043 
1044 	for (i = 0; i < AR_BUFFERS; i++)
1045 		ar_context_link_page(ctx, i);
1046 
1047 	ctx->pointer = ctx->buffer;
1048 
1049 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1050 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1051 }
1052 
1053 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1054 {
1055 	__le16 branch;
1056 
1057 	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1058 
1059 	/* figure out which descriptor the branch address goes in */
1060 	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1061 		return d;
1062 	else
1063 		return d + z - 1;
1064 }
1065 
1066 static void context_tasklet(unsigned long data)
1067 {
1068 	struct context *ctx = (struct context *) data;
1069 	struct descriptor *d, *last;
1070 	u32 address;
1071 	int z;
1072 	struct descriptor_buffer *desc;
1073 
1074 	desc = list_entry(ctx->buffer_list.next,
1075 			struct descriptor_buffer, list);
1076 	last = ctx->last;
1077 	while (last->branch_address != 0) {
1078 		struct descriptor_buffer *old_desc = desc;
1079 		address = le32_to_cpu(last->branch_address);
1080 		z = address & 0xf;
1081 		address &= ~0xf;
1082 		ctx->current_bus = address;
1083 
1084 		/* If the branch address points to a buffer outside of the
1085 		 * current buffer, advance to the next buffer. */
1086 		if (address < desc->buffer_bus ||
1087 				address >= desc->buffer_bus + desc->used)
1088 			desc = list_entry(desc->list.next,
1089 					struct descriptor_buffer, list);
1090 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1091 		last = find_branch_descriptor(d, z);
1092 
1093 		if (!ctx->callback(ctx, d, last))
1094 			break;
1095 
1096 		if (old_desc != desc) {
1097 			/* If we've advanced to the next buffer, move the
1098 			 * previous buffer to the free list. */
1099 			unsigned long flags;
1100 			old_desc->used = 0;
1101 			spin_lock_irqsave(&ctx->ohci->lock, flags);
1102 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1103 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1104 		}
1105 		ctx->last = last;
1106 	}
1107 }
1108 
1109 /*
1110  * Allocate a new buffer and add it to the list of free buffers for this
1111  * context.  Must be called with ohci->lock held.
1112  */
1113 static int context_add_buffer(struct context *ctx)
1114 {
1115 	struct descriptor_buffer *desc;
1116 	dma_addr_t uninitialized_var(bus_addr);
1117 	int offset;
1118 
1119 	/*
1120 	 * 16MB of descriptors should be far more than enough for any DMA
1121 	 * program.  This will catch run-away userspace or DoS attacks.
1122 	 */
1123 	if (ctx->total_allocation >= 16*1024*1024)
1124 		return -ENOMEM;
1125 
1126 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1127 			&bus_addr, GFP_ATOMIC);
1128 	if (!desc)
1129 		return -ENOMEM;
1130 
1131 	offset = (void *)&desc->buffer - (void *)desc;
1132 	desc->buffer_size = PAGE_SIZE - offset;
1133 	desc->buffer_bus = bus_addr + offset;
1134 	desc->used = 0;
1135 
1136 	list_add_tail(&desc->list, &ctx->buffer_list);
1137 	ctx->total_allocation += PAGE_SIZE;
1138 
1139 	return 0;
1140 }
1141 
1142 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1143 			u32 regs, descriptor_callback_t callback)
1144 {
1145 	ctx->ohci = ohci;
1146 	ctx->regs = regs;
1147 	ctx->total_allocation = 0;
1148 
1149 	INIT_LIST_HEAD(&ctx->buffer_list);
1150 	if (context_add_buffer(ctx) < 0)
1151 		return -ENOMEM;
1152 
1153 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1154 			struct descriptor_buffer, list);
1155 
1156 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1157 	ctx->callback = callback;
1158 
1159 	/*
1160 	 * We put a dummy descriptor in the buffer that has a NULL
1161 	 * branch address and looks like it's been sent.  That way we
1162 	 * have a descriptor to append DMA programs to.
1163 	 */
1164 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1165 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1166 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1167 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1168 	ctx->last = ctx->buffer_tail->buffer;
1169 	ctx->prev = ctx->buffer_tail->buffer;
1170 	ctx->prev_z = 1;
1171 
1172 	return 0;
1173 }
1174 
1175 static void context_release(struct context *ctx)
1176 {
1177 	struct fw_card *card = &ctx->ohci->card;
1178 	struct descriptor_buffer *desc, *tmp;
1179 
1180 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1181 		dma_free_coherent(card->device, PAGE_SIZE, desc,
1182 			desc->buffer_bus -
1183 			((void *)&desc->buffer - (void *)desc));
1184 }
1185 
1186 /* Must be called with ohci->lock held */
1187 static struct descriptor *context_get_descriptors(struct context *ctx,
1188 						  int z, dma_addr_t *d_bus)
1189 {
1190 	struct descriptor *d = NULL;
1191 	struct descriptor_buffer *desc = ctx->buffer_tail;
1192 
1193 	if (z * sizeof(*d) > desc->buffer_size)
1194 		return NULL;
1195 
1196 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1197 		/* No room for the descriptor in this buffer, so advance to the
1198 		 * next one. */
1199 
1200 		if (desc->list.next == &ctx->buffer_list) {
1201 			/* If there is no free buffer next in the list,
1202 			 * allocate one. */
1203 			if (context_add_buffer(ctx) < 0)
1204 				return NULL;
1205 		}
1206 		desc = list_entry(desc->list.next,
1207 				struct descriptor_buffer, list);
1208 		ctx->buffer_tail = desc;
1209 	}
1210 
1211 	d = desc->buffer + desc->used / sizeof(*d);
1212 	memset(d, 0, z * sizeof(*d));
1213 	*d_bus = desc->buffer_bus + desc->used;
1214 
1215 	return d;
1216 }
1217 
1218 static void context_run(struct context *ctx, u32 extra)
1219 {
1220 	struct fw_ohci *ohci = ctx->ohci;
1221 
1222 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1223 		  le32_to_cpu(ctx->last->branch_address));
1224 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1225 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1226 	ctx->running = true;
1227 	flush_writes(ohci);
1228 }
1229 
1230 static void context_append(struct context *ctx,
1231 			   struct descriptor *d, int z, int extra)
1232 {
1233 	dma_addr_t d_bus;
1234 	struct descriptor_buffer *desc = ctx->buffer_tail;
1235 	struct descriptor *d_branch;
1236 
1237 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1238 
1239 	desc->used += (z + extra) * sizeof(*d);
1240 
1241 	wmb(); /* finish init of new descriptors before branch_address update */
1242 
1243 	d_branch = find_branch_descriptor(ctx->prev, ctx->prev_z);
1244 	d_branch->branch_address = cpu_to_le32(d_bus | z);
1245 
1246 	/*
1247 	 * VT6306 incorrectly checks only the single descriptor at the
1248 	 * CommandPtr when the wake bit is written, so if it's a
1249 	 * multi-descriptor block starting with an INPUT_MORE, put a copy of
1250 	 * the branch address in the first descriptor.
1251 	 *
1252 	 * Not doing this for transmit contexts since not sure how it interacts
1253 	 * with skip addresses.
1254 	 */
1255 	if (unlikely(ctx->ohci->quirks & QUIRK_IR_WAKE) &&
1256 	    d_branch != ctx->prev &&
1257 	    (ctx->prev->control & cpu_to_le16(DESCRIPTOR_CMD)) ==
1258 	     cpu_to_le16(DESCRIPTOR_INPUT_MORE)) {
1259 		ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1260 	}
1261 
1262 	ctx->prev = d;
1263 	ctx->prev_z = z;
1264 }
1265 
1266 static void context_stop(struct context *ctx)
1267 {
1268 	struct fw_ohci *ohci = ctx->ohci;
1269 	u32 reg;
1270 	int i;
1271 
1272 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1273 	ctx->running = false;
1274 
1275 	for (i = 0; i < 1000; i++) {
1276 		reg = reg_read(ohci, CONTROL_SET(ctx->regs));
1277 		if ((reg & CONTEXT_ACTIVE) == 0)
1278 			return;
1279 
1280 		if (i)
1281 			udelay(10);
1282 	}
1283 	ohci_err(ohci, "DMA context still active (0x%08x)\n", reg);
1284 }
1285 
1286 struct driver_data {
1287 	u8 inline_data[8];
1288 	struct fw_packet *packet;
1289 };
1290 
1291 /*
1292  * This function apppends a packet to the DMA queue for transmission.
1293  * Must always be called with the ochi->lock held to ensure proper
1294  * generation handling and locking around packet queue manipulation.
1295  */
1296 static int at_context_queue_packet(struct context *ctx,
1297 				   struct fw_packet *packet)
1298 {
1299 	struct fw_ohci *ohci = ctx->ohci;
1300 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1301 	struct driver_data *driver_data;
1302 	struct descriptor *d, *last;
1303 	__le32 *header;
1304 	int z, tcode;
1305 
1306 	d = context_get_descriptors(ctx, 4, &d_bus);
1307 	if (d == NULL) {
1308 		packet->ack = RCODE_SEND_ERROR;
1309 		return -1;
1310 	}
1311 
1312 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1313 	d[0].res_count = cpu_to_le16(packet->timestamp);
1314 
1315 	/*
1316 	 * The DMA format for asynchronous link packets is different
1317 	 * from the IEEE1394 layout, so shift the fields around
1318 	 * accordingly.
1319 	 */
1320 
1321 	tcode = (packet->header[0] >> 4) & 0x0f;
1322 	header = (__le32 *) &d[1];
1323 	switch (tcode) {
1324 	case TCODE_WRITE_QUADLET_REQUEST:
1325 	case TCODE_WRITE_BLOCK_REQUEST:
1326 	case TCODE_WRITE_RESPONSE:
1327 	case TCODE_READ_QUADLET_REQUEST:
1328 	case TCODE_READ_BLOCK_REQUEST:
1329 	case TCODE_READ_QUADLET_RESPONSE:
1330 	case TCODE_READ_BLOCK_RESPONSE:
1331 	case TCODE_LOCK_REQUEST:
1332 	case TCODE_LOCK_RESPONSE:
1333 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1334 					(packet->speed << 16));
1335 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1336 					(packet->header[0] & 0xffff0000));
1337 		header[2] = cpu_to_le32(packet->header[2]);
1338 
1339 		if (TCODE_IS_BLOCK_PACKET(tcode))
1340 			header[3] = cpu_to_le32(packet->header[3]);
1341 		else
1342 			header[3] = (__force __le32) packet->header[3];
1343 
1344 		d[0].req_count = cpu_to_le16(packet->header_length);
1345 		break;
1346 
1347 	case TCODE_LINK_INTERNAL:
1348 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1349 					(packet->speed << 16));
1350 		header[1] = cpu_to_le32(packet->header[1]);
1351 		header[2] = cpu_to_le32(packet->header[2]);
1352 		d[0].req_count = cpu_to_le16(12);
1353 
1354 		if (is_ping_packet(&packet->header[1]))
1355 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1356 		break;
1357 
1358 	case TCODE_STREAM_DATA:
1359 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1360 					(packet->speed << 16));
1361 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1362 		d[0].req_count = cpu_to_le16(8);
1363 		break;
1364 
1365 	default:
1366 		/* BUG(); */
1367 		packet->ack = RCODE_SEND_ERROR;
1368 		return -1;
1369 	}
1370 
1371 	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1372 	driver_data = (struct driver_data *) &d[3];
1373 	driver_data->packet = packet;
1374 	packet->driver_data = driver_data;
1375 
1376 	if (packet->payload_length > 0) {
1377 		if (packet->payload_length > sizeof(driver_data->inline_data)) {
1378 			payload_bus = dma_map_single(ohci->card.device,
1379 						     packet->payload,
1380 						     packet->payload_length,
1381 						     DMA_TO_DEVICE);
1382 			if (dma_mapping_error(ohci->card.device, payload_bus)) {
1383 				packet->ack = RCODE_SEND_ERROR;
1384 				return -1;
1385 			}
1386 			packet->payload_bus	= payload_bus;
1387 			packet->payload_mapped	= true;
1388 		} else {
1389 			memcpy(driver_data->inline_data, packet->payload,
1390 			       packet->payload_length);
1391 			payload_bus = d_bus + 3 * sizeof(*d);
1392 		}
1393 
1394 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1395 		d[2].data_address = cpu_to_le32(payload_bus);
1396 		last = &d[2];
1397 		z = 3;
1398 	} else {
1399 		last = &d[0];
1400 		z = 2;
1401 	}
1402 
1403 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1404 				     DESCRIPTOR_IRQ_ALWAYS |
1405 				     DESCRIPTOR_BRANCH_ALWAYS);
1406 
1407 	/* FIXME: Document how the locking works. */
1408 	if (ohci->generation != packet->generation) {
1409 		if (packet->payload_mapped)
1410 			dma_unmap_single(ohci->card.device, payload_bus,
1411 					 packet->payload_length, DMA_TO_DEVICE);
1412 		packet->ack = RCODE_GENERATION;
1413 		return -1;
1414 	}
1415 
1416 	context_append(ctx, d, z, 4 - z);
1417 
1418 	if (ctx->running)
1419 		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1420 	else
1421 		context_run(ctx, 0);
1422 
1423 	return 0;
1424 }
1425 
1426 static void at_context_flush(struct context *ctx)
1427 {
1428 	tasklet_disable(&ctx->tasklet);
1429 
1430 	ctx->flushing = true;
1431 	context_tasklet((unsigned long)ctx);
1432 	ctx->flushing = false;
1433 
1434 	tasklet_enable(&ctx->tasklet);
1435 }
1436 
1437 static int handle_at_packet(struct context *context,
1438 			    struct descriptor *d,
1439 			    struct descriptor *last)
1440 {
1441 	struct driver_data *driver_data;
1442 	struct fw_packet *packet;
1443 	struct fw_ohci *ohci = context->ohci;
1444 	int evt;
1445 
1446 	if (last->transfer_status == 0 && !context->flushing)
1447 		/* This descriptor isn't done yet, stop iteration. */
1448 		return 0;
1449 
1450 	driver_data = (struct driver_data *) &d[3];
1451 	packet = driver_data->packet;
1452 	if (packet == NULL)
1453 		/* This packet was cancelled, just continue. */
1454 		return 1;
1455 
1456 	if (packet->payload_mapped)
1457 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1458 				 packet->payload_length, DMA_TO_DEVICE);
1459 
1460 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1461 	packet->timestamp = le16_to_cpu(last->res_count);
1462 
1463 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);
1464 
1465 	switch (evt) {
1466 	case OHCI1394_evt_timeout:
1467 		/* Async response transmit timed out. */
1468 		packet->ack = RCODE_CANCELLED;
1469 		break;
1470 
1471 	case OHCI1394_evt_flushed:
1472 		/*
1473 		 * The packet was flushed should give same error as
1474 		 * when we try to use a stale generation count.
1475 		 */
1476 		packet->ack = RCODE_GENERATION;
1477 		break;
1478 
1479 	case OHCI1394_evt_missing_ack:
1480 		if (context->flushing)
1481 			packet->ack = RCODE_GENERATION;
1482 		else {
1483 			/*
1484 			 * Using a valid (current) generation count, but the
1485 			 * node is not on the bus or not sending acks.
1486 			 */
1487 			packet->ack = RCODE_NO_ACK;
1488 		}
1489 		break;
1490 
1491 	case ACK_COMPLETE + 0x10:
1492 	case ACK_PENDING + 0x10:
1493 	case ACK_BUSY_X + 0x10:
1494 	case ACK_BUSY_A + 0x10:
1495 	case ACK_BUSY_B + 0x10:
1496 	case ACK_DATA_ERROR + 0x10:
1497 	case ACK_TYPE_ERROR + 0x10:
1498 		packet->ack = evt - 0x10;
1499 		break;
1500 
1501 	case OHCI1394_evt_no_status:
1502 		if (context->flushing) {
1503 			packet->ack = RCODE_GENERATION;
1504 			break;
1505 		}
1506 		/* fall through */
1507 
1508 	default:
1509 		packet->ack = RCODE_SEND_ERROR;
1510 		break;
1511 	}
1512 
1513 	packet->callback(packet, &ohci->card, packet->ack);
1514 
1515 	return 1;
1516 }
1517 
1518 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1519 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1520 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1521 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1522 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1523 
1524 static void handle_local_rom(struct fw_ohci *ohci,
1525 			     struct fw_packet *packet, u32 csr)
1526 {
1527 	struct fw_packet response;
1528 	int tcode, length, i;
1529 
1530 	tcode = HEADER_GET_TCODE(packet->header[0]);
1531 	if (TCODE_IS_BLOCK_PACKET(tcode))
1532 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1533 	else
1534 		length = 4;
1535 
1536 	i = csr - CSR_CONFIG_ROM;
1537 	if (i + length > CONFIG_ROM_SIZE) {
1538 		fw_fill_response(&response, packet->header,
1539 				 RCODE_ADDRESS_ERROR, NULL, 0);
1540 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1541 		fw_fill_response(&response, packet->header,
1542 				 RCODE_TYPE_ERROR, NULL, 0);
1543 	} else {
1544 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1545 				 (void *) ohci->config_rom + i, length);
1546 	}
1547 
1548 	fw_core_handle_response(&ohci->card, &response);
1549 }
1550 
1551 static void handle_local_lock(struct fw_ohci *ohci,
1552 			      struct fw_packet *packet, u32 csr)
1553 {
1554 	struct fw_packet response;
1555 	int tcode, length, ext_tcode, sel, try;
1556 	__be32 *payload, lock_old;
1557 	u32 lock_arg, lock_data;
1558 
1559 	tcode = HEADER_GET_TCODE(packet->header[0]);
1560 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1561 	payload = packet->payload;
1562 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1563 
1564 	if (tcode == TCODE_LOCK_REQUEST &&
1565 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1566 		lock_arg = be32_to_cpu(payload[0]);
1567 		lock_data = be32_to_cpu(payload[1]);
1568 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1569 		lock_arg = 0;
1570 		lock_data = 0;
1571 	} else {
1572 		fw_fill_response(&response, packet->header,
1573 				 RCODE_TYPE_ERROR, NULL, 0);
1574 		goto out;
1575 	}
1576 
1577 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1578 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1579 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1580 	reg_write(ohci, OHCI1394_CSRControl, sel);
1581 
1582 	for (try = 0; try < 20; try++)
1583 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1584 			lock_old = cpu_to_be32(reg_read(ohci,
1585 							OHCI1394_CSRData));
1586 			fw_fill_response(&response, packet->header,
1587 					 RCODE_COMPLETE,
1588 					 &lock_old, sizeof(lock_old));
1589 			goto out;
1590 		}
1591 
1592 	ohci_err(ohci, "swap not done (CSR lock timeout)\n");
1593 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1594 
1595  out:
1596 	fw_core_handle_response(&ohci->card, &response);
1597 }
1598 
1599 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1600 {
1601 	u64 offset, csr;
1602 
1603 	if (ctx == &ctx->ohci->at_request_ctx) {
1604 		packet->ack = ACK_PENDING;
1605 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1606 	}
1607 
1608 	offset =
1609 		((unsigned long long)
1610 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1611 		packet->header[2];
1612 	csr = offset - CSR_REGISTER_BASE;
1613 
1614 	/* Handle config rom reads. */
1615 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1616 		handle_local_rom(ctx->ohci, packet, csr);
1617 	else switch (csr) {
1618 	case CSR_BUS_MANAGER_ID:
1619 	case CSR_BANDWIDTH_AVAILABLE:
1620 	case CSR_CHANNELS_AVAILABLE_HI:
1621 	case CSR_CHANNELS_AVAILABLE_LO:
1622 		handle_local_lock(ctx->ohci, packet, csr);
1623 		break;
1624 	default:
1625 		if (ctx == &ctx->ohci->at_request_ctx)
1626 			fw_core_handle_request(&ctx->ohci->card, packet);
1627 		else
1628 			fw_core_handle_response(&ctx->ohci->card, packet);
1629 		break;
1630 	}
1631 
1632 	if (ctx == &ctx->ohci->at_response_ctx) {
1633 		packet->ack = ACK_COMPLETE;
1634 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1635 	}
1636 }
1637 
1638 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1639 {
1640 	unsigned long flags;
1641 	int ret;
1642 
1643 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1644 
1645 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1646 	    ctx->ohci->generation == packet->generation) {
1647 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1648 		handle_local_request(ctx, packet);
1649 		return;
1650 	}
1651 
1652 	ret = at_context_queue_packet(ctx, packet);
1653 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1654 
1655 	if (ret < 0)
1656 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1657 
1658 }
1659 
1660 static void detect_dead_context(struct fw_ohci *ohci,
1661 				const char *name, unsigned int regs)
1662 {
1663 	u32 ctl;
1664 
1665 	ctl = reg_read(ohci, CONTROL_SET(regs));
1666 	if (ctl & CONTEXT_DEAD)
1667 		ohci_err(ohci, "DMA context %s has stopped, error code: %s\n",
1668 			name, evts[ctl & 0x1f]);
1669 }
1670 
1671 static void handle_dead_contexts(struct fw_ohci *ohci)
1672 {
1673 	unsigned int i;
1674 	char name[8];
1675 
1676 	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1677 	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1678 	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1679 	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1680 	for (i = 0; i < 32; ++i) {
1681 		if (!(ohci->it_context_support & (1 << i)))
1682 			continue;
1683 		sprintf(name, "IT%u", i);
1684 		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1685 	}
1686 	for (i = 0; i < 32; ++i) {
1687 		if (!(ohci->ir_context_support & (1 << i)))
1688 			continue;
1689 		sprintf(name, "IR%u", i);
1690 		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1691 	}
1692 	/* TODO: maybe try to flush and restart the dead contexts */
1693 }
1694 
1695 static u32 cycle_timer_ticks(u32 cycle_timer)
1696 {
1697 	u32 ticks;
1698 
1699 	ticks = cycle_timer & 0xfff;
1700 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1701 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1702 
1703 	return ticks;
1704 }
1705 
1706 /*
1707  * Some controllers exhibit one or more of the following bugs when updating the
1708  * iso cycle timer register:
1709  *  - When the lowest six bits are wrapping around to zero, a read that happens
1710  *    at the same time will return garbage in the lowest ten bits.
1711  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1712  *    not incremented for about 60 ns.
1713  *  - Occasionally, the entire register reads zero.
1714  *
1715  * To catch these, we read the register three times and ensure that the
1716  * difference between each two consecutive reads is approximately the same, i.e.
1717  * less than twice the other.  Furthermore, any negative difference indicates an
1718  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1719  * execute, so we have enough precision to compute the ratio of the differences.)
1720  */
1721 static u32 get_cycle_time(struct fw_ohci *ohci)
1722 {
1723 	u32 c0, c1, c2;
1724 	u32 t0, t1, t2;
1725 	s32 diff01, diff12;
1726 	int i;
1727 
1728 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1729 
1730 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1731 		i = 0;
1732 		c1 = c2;
1733 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1734 		do {
1735 			c0 = c1;
1736 			c1 = c2;
1737 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1738 			t0 = cycle_timer_ticks(c0);
1739 			t1 = cycle_timer_ticks(c1);
1740 			t2 = cycle_timer_ticks(c2);
1741 			diff01 = t1 - t0;
1742 			diff12 = t2 - t1;
1743 		} while ((diff01 <= 0 || diff12 <= 0 ||
1744 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1745 			 && i++ < 20);
1746 	}
1747 
1748 	return c2;
1749 }
1750 
1751 /*
1752  * This function has to be called at least every 64 seconds.  The bus_time
1753  * field stores not only the upper 25 bits of the BUS_TIME register but also
1754  * the most significant bit of the cycle timer in bit 6 so that we can detect
1755  * changes in this bit.
1756  */
1757 static u32 update_bus_time(struct fw_ohci *ohci)
1758 {
1759 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1760 
1761 	if (unlikely(!ohci->bus_time_running)) {
1762 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_cycle64Seconds);
1763 		ohci->bus_time = (lower_32_bits(get_seconds()) & ~0x7f) |
1764 		                 (cycle_time_seconds & 0x40);
1765 		ohci->bus_time_running = true;
1766 	}
1767 
1768 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1769 		ohci->bus_time += 0x40;
1770 
1771 	return ohci->bus_time | cycle_time_seconds;
1772 }
1773 
1774 static int get_status_for_port(struct fw_ohci *ohci, int port_index)
1775 {
1776 	int reg;
1777 
1778 	mutex_lock(&ohci->phy_reg_mutex);
1779 	reg = write_phy_reg(ohci, 7, port_index);
1780 	if (reg >= 0)
1781 		reg = read_phy_reg(ohci, 8);
1782 	mutex_unlock(&ohci->phy_reg_mutex);
1783 	if (reg < 0)
1784 		return reg;
1785 
1786 	switch (reg & 0x0f) {
1787 	case 0x06:
1788 		return 2;	/* is child node (connected to parent node) */
1789 	case 0x0e:
1790 		return 3;	/* is parent node (connected to child node) */
1791 	}
1792 	return 1;		/* not connected */
1793 }
1794 
1795 static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
1796 	int self_id_count)
1797 {
1798 	int i;
1799 	u32 entry;
1800 
1801 	for (i = 0; i < self_id_count; i++) {
1802 		entry = ohci->self_id_buffer[i];
1803 		if ((self_id & 0xff000000) == (entry & 0xff000000))
1804 			return -1;
1805 		if ((self_id & 0xff000000) < (entry & 0xff000000))
1806 			return i;
1807 	}
1808 	return i;
1809 }
1810 
1811 static int initiated_reset(struct fw_ohci *ohci)
1812 {
1813 	int reg;
1814 	int ret = 0;
1815 
1816 	mutex_lock(&ohci->phy_reg_mutex);
1817 	reg = write_phy_reg(ohci, 7, 0xe0); /* Select page 7 */
1818 	if (reg >= 0) {
1819 		reg = read_phy_reg(ohci, 8);
1820 		reg |= 0x40;
1821 		reg = write_phy_reg(ohci, 8, reg); /* set PMODE bit */
1822 		if (reg >= 0) {
1823 			reg = read_phy_reg(ohci, 12); /* read register 12 */
1824 			if (reg >= 0) {
1825 				if ((reg & 0x08) == 0x08) {
1826 					/* bit 3 indicates "initiated reset" */
1827 					ret = 0x2;
1828 				}
1829 			}
1830 		}
1831 	}
1832 	mutex_unlock(&ohci->phy_reg_mutex);
1833 	return ret;
1834 }
1835 
1836 /*
1837  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1838  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1839  * Construct the selfID from phy register contents.
1840  */
1841 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
1842 {
1843 	int reg, i, pos, status;
1844 	/* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
1845 	u32 self_id = 0x8040c800;
1846 
1847 	reg = reg_read(ohci, OHCI1394_NodeID);
1848 	if (!(reg & OHCI1394_NodeID_idValid)) {
1849 		ohci_notice(ohci,
1850 			    "node ID not valid, new bus reset in progress\n");
1851 		return -EBUSY;
1852 	}
1853 	self_id |= ((reg & 0x3f) << 24); /* phy ID */
1854 
1855 	reg = ohci_read_phy_reg(&ohci->card, 4);
1856 	if (reg < 0)
1857 		return reg;
1858 	self_id |= ((reg & 0x07) << 8); /* power class */
1859 
1860 	reg = ohci_read_phy_reg(&ohci->card, 1);
1861 	if (reg < 0)
1862 		return reg;
1863 	self_id |= ((reg & 0x3f) << 16); /* gap count */
1864 
1865 	for (i = 0; i < 3; i++) {
1866 		status = get_status_for_port(ohci, i);
1867 		if (status < 0)
1868 			return status;
1869 		self_id |= ((status & 0x3) << (6 - (i * 2)));
1870 	}
1871 
1872 	self_id |= initiated_reset(ohci);
1873 
1874 	pos = get_self_id_pos(ohci, self_id, self_id_count);
1875 	if (pos >= 0) {
1876 		memmove(&(ohci->self_id_buffer[pos+1]),
1877 			&(ohci->self_id_buffer[pos]),
1878 			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
1879 		ohci->self_id_buffer[pos] = self_id;
1880 		self_id_count++;
1881 	}
1882 	return self_id_count;
1883 }
1884 
1885 static void bus_reset_work(struct work_struct *work)
1886 {
1887 	struct fw_ohci *ohci =
1888 		container_of(work, struct fw_ohci, bus_reset_work);
1889 	int self_id_count, generation, new_generation, i, j;
1890 	u32 reg;
1891 	void *free_rom = NULL;
1892 	dma_addr_t free_rom_bus = 0;
1893 	bool is_new_root;
1894 
1895 	reg = reg_read(ohci, OHCI1394_NodeID);
1896 	if (!(reg & OHCI1394_NodeID_idValid)) {
1897 		ohci_notice(ohci,
1898 			    "node ID not valid, new bus reset in progress\n");
1899 		return;
1900 	}
1901 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1902 		ohci_notice(ohci, "malconfigured bus\n");
1903 		return;
1904 	}
1905 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1906 			       OHCI1394_NodeID_nodeNumber);
1907 
1908 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1909 	if (!(ohci->is_root && is_new_root))
1910 		reg_write(ohci, OHCI1394_LinkControlSet,
1911 			  OHCI1394_LinkControl_cycleMaster);
1912 	ohci->is_root = is_new_root;
1913 
1914 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1915 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1916 		ohci_notice(ohci, "self ID receive error\n");
1917 		return;
1918 	}
1919 	/*
1920 	 * The count in the SelfIDCount register is the number of
1921 	 * bytes in the self ID receive buffer.  Since we also receive
1922 	 * the inverted quadlets and a header quadlet, we shift one
1923 	 * bit extra to get the actual number of self IDs.
1924 	 */
1925 	self_id_count = (reg >> 3) & 0xff;
1926 
1927 	if (self_id_count > 252) {
1928 		ohci_notice(ohci, "bad selfIDSize (%08x)\n", reg);
1929 		return;
1930 	}
1931 
1932 	generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1933 	rmb();
1934 
1935 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1936 		u32 id  = cond_le32_to_cpu(ohci->self_id_cpu[i]);
1937 		u32 id2 = cond_le32_to_cpu(ohci->self_id_cpu[i + 1]);
1938 
1939 		if (id != ~id2) {
1940 			/*
1941 			 * If the invalid data looks like a cycle start packet,
1942 			 * it's likely to be the result of the cycle master
1943 			 * having a wrong gap count.  In this case, the self IDs
1944 			 * so far are valid and should be processed so that the
1945 			 * bus manager can then correct the gap count.
1946 			 */
1947 			if (id == 0xffff008f) {
1948 				ohci_notice(ohci, "ignoring spurious self IDs\n");
1949 				self_id_count = j;
1950 				break;
1951 			}
1952 
1953 			ohci_notice(ohci, "bad self ID %d/%d (%08x != ~%08x)\n",
1954 				    j, self_id_count, id, id2);
1955 			return;
1956 		}
1957 		ohci->self_id_buffer[j] = id;
1958 	}
1959 
1960 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
1961 		self_id_count = find_and_insert_self_id(ohci, self_id_count);
1962 		if (self_id_count < 0) {
1963 			ohci_notice(ohci,
1964 				    "could not construct local self ID\n");
1965 			return;
1966 		}
1967 	}
1968 
1969 	if (self_id_count == 0) {
1970 		ohci_notice(ohci, "no self IDs\n");
1971 		return;
1972 	}
1973 	rmb();
1974 
1975 	/*
1976 	 * Check the consistency of the self IDs we just read.  The
1977 	 * problem we face is that a new bus reset can start while we
1978 	 * read out the self IDs from the DMA buffer. If this happens,
1979 	 * the DMA buffer will be overwritten with new self IDs and we
1980 	 * will read out inconsistent data.  The OHCI specification
1981 	 * (section 11.2) recommends a technique similar to
1982 	 * linux/seqlock.h, where we remember the generation of the
1983 	 * self IDs in the buffer before reading them out and compare
1984 	 * it to the current generation after reading them out.  If
1985 	 * the two generations match we know we have a consistent set
1986 	 * of self IDs.
1987 	 */
1988 
1989 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1990 	if (new_generation != generation) {
1991 		ohci_notice(ohci, "new bus reset, discarding self ids\n");
1992 		return;
1993 	}
1994 
1995 	/* FIXME: Document how the locking works. */
1996 	spin_lock_irq(&ohci->lock);
1997 
1998 	ohci->generation = -1; /* prevent AT packet queueing */
1999 	context_stop(&ohci->at_request_ctx);
2000 	context_stop(&ohci->at_response_ctx);
2001 
2002 	spin_unlock_irq(&ohci->lock);
2003 
2004 	/*
2005 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
2006 	 * packets in the AT queues and software needs to drain them.
2007 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
2008 	 */
2009 	at_context_flush(&ohci->at_request_ctx);
2010 	at_context_flush(&ohci->at_response_ctx);
2011 
2012 	spin_lock_irq(&ohci->lock);
2013 
2014 	ohci->generation = generation;
2015 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
2016 
2017 	if (ohci->quirks & QUIRK_RESET_PACKET)
2018 		ohci->request_generation = generation;
2019 
2020 	/*
2021 	 * This next bit is unrelated to the AT context stuff but we
2022 	 * have to do it under the spinlock also.  If a new config rom
2023 	 * was set up before this reset, the old one is now no longer
2024 	 * in use and we can free it. Update the config rom pointers
2025 	 * to point to the current config rom and clear the
2026 	 * next_config_rom pointer so a new update can take place.
2027 	 */
2028 
2029 	if (ohci->next_config_rom != NULL) {
2030 		if (ohci->next_config_rom != ohci->config_rom) {
2031 			free_rom      = ohci->config_rom;
2032 			free_rom_bus  = ohci->config_rom_bus;
2033 		}
2034 		ohci->config_rom      = ohci->next_config_rom;
2035 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
2036 		ohci->next_config_rom = NULL;
2037 
2038 		/*
2039 		 * Restore config_rom image and manually update
2040 		 * config_rom registers.  Writing the header quadlet
2041 		 * will indicate that the config rom is ready, so we
2042 		 * do that last.
2043 		 */
2044 		reg_write(ohci, OHCI1394_BusOptions,
2045 			  be32_to_cpu(ohci->config_rom[2]));
2046 		ohci->config_rom[0] = ohci->next_header;
2047 		reg_write(ohci, OHCI1394_ConfigROMhdr,
2048 			  be32_to_cpu(ohci->next_header));
2049 	}
2050 
2051 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2052 	reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
2053 	reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
2054 #endif
2055 
2056 	spin_unlock_irq(&ohci->lock);
2057 
2058 	if (free_rom)
2059 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2060 				  free_rom, free_rom_bus);
2061 
2062 	log_selfids(ohci, generation, self_id_count);
2063 
2064 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2065 				 self_id_count, ohci->self_id_buffer,
2066 				 ohci->csr_state_setclear_abdicate);
2067 	ohci->csr_state_setclear_abdicate = false;
2068 }
2069 
2070 static irqreturn_t irq_handler(int irq, void *data)
2071 {
2072 	struct fw_ohci *ohci = data;
2073 	u32 event, iso_event;
2074 	int i;
2075 
2076 	event = reg_read(ohci, OHCI1394_IntEventClear);
2077 
2078 	if (!event || !~event)
2079 		return IRQ_NONE;
2080 
2081 	/*
2082 	 * busReset and postedWriteErr must not be cleared yet
2083 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2084 	 */
2085 	reg_write(ohci, OHCI1394_IntEventClear,
2086 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2087 	log_irqs(ohci, event);
2088 
2089 	if (event & OHCI1394_selfIDComplete)
2090 		queue_work(fw_workqueue, &ohci->bus_reset_work);
2091 
2092 	if (event & OHCI1394_RQPkt)
2093 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2094 
2095 	if (event & OHCI1394_RSPkt)
2096 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2097 
2098 	if (event & OHCI1394_reqTxComplete)
2099 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
2100 
2101 	if (event & OHCI1394_respTxComplete)
2102 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
2103 
2104 	if (event & OHCI1394_isochRx) {
2105 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2106 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2107 
2108 		while (iso_event) {
2109 			i = ffs(iso_event) - 1;
2110 			tasklet_schedule(
2111 				&ohci->ir_context_list[i].context.tasklet);
2112 			iso_event &= ~(1 << i);
2113 		}
2114 	}
2115 
2116 	if (event & OHCI1394_isochTx) {
2117 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2118 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2119 
2120 		while (iso_event) {
2121 			i = ffs(iso_event) - 1;
2122 			tasklet_schedule(
2123 				&ohci->it_context_list[i].context.tasklet);
2124 			iso_event &= ~(1 << i);
2125 		}
2126 	}
2127 
2128 	if (unlikely(event & OHCI1394_regAccessFail))
2129 		ohci_err(ohci, "register access failure\n");
2130 
2131 	if (unlikely(event & OHCI1394_postedWriteErr)) {
2132 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2133 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2134 		reg_write(ohci, OHCI1394_IntEventClear,
2135 			  OHCI1394_postedWriteErr);
2136 		if (printk_ratelimit())
2137 			ohci_err(ohci, "PCI posted write error\n");
2138 	}
2139 
2140 	if (unlikely(event & OHCI1394_cycleTooLong)) {
2141 		if (printk_ratelimit())
2142 			ohci_notice(ohci, "isochronous cycle too long\n");
2143 		reg_write(ohci, OHCI1394_LinkControlSet,
2144 			  OHCI1394_LinkControl_cycleMaster);
2145 	}
2146 
2147 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
2148 		/*
2149 		 * We need to clear this event bit in order to make
2150 		 * cycleMatch isochronous I/O work.  In theory we should
2151 		 * stop active cycleMatch iso contexts now and restart
2152 		 * them at least two cycles later.  (FIXME?)
2153 		 */
2154 		if (printk_ratelimit())
2155 			ohci_notice(ohci, "isochronous cycle inconsistent\n");
2156 	}
2157 
2158 	if (unlikely(event & OHCI1394_unrecoverableError))
2159 		handle_dead_contexts(ohci);
2160 
2161 	if (event & OHCI1394_cycle64Seconds) {
2162 		spin_lock(&ohci->lock);
2163 		update_bus_time(ohci);
2164 		spin_unlock(&ohci->lock);
2165 	} else
2166 		flush_writes(ohci);
2167 
2168 	return IRQ_HANDLED;
2169 }
2170 
2171 static int software_reset(struct fw_ohci *ohci)
2172 {
2173 	u32 val;
2174 	int i;
2175 
2176 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2177 	for (i = 0; i < 500; i++) {
2178 		val = reg_read(ohci, OHCI1394_HCControlSet);
2179 		if (!~val)
2180 			return -ENODEV; /* Card was ejected. */
2181 
2182 		if (!(val & OHCI1394_HCControl_softReset))
2183 			return 0;
2184 
2185 		msleep(1);
2186 	}
2187 
2188 	return -EBUSY;
2189 }
2190 
2191 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2192 {
2193 	size_t size = length * 4;
2194 
2195 	memcpy(dest, src, size);
2196 	if (size < CONFIG_ROM_SIZE)
2197 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2198 }
2199 
2200 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2201 {
2202 	bool enable_1394a;
2203 	int ret, clear, set, offset;
2204 
2205 	/* Check if the driver should configure link and PHY. */
2206 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2207 	      OHCI1394_HCControl_programPhyEnable))
2208 		return 0;
2209 
2210 	/* Paranoia: check whether the PHY supports 1394a, too. */
2211 	enable_1394a = false;
2212 	ret = read_phy_reg(ohci, 2);
2213 	if (ret < 0)
2214 		return ret;
2215 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2216 		ret = read_paged_phy_reg(ohci, 1, 8);
2217 		if (ret < 0)
2218 			return ret;
2219 		if (ret >= 1)
2220 			enable_1394a = true;
2221 	}
2222 
2223 	if (ohci->quirks & QUIRK_NO_1394A)
2224 		enable_1394a = false;
2225 
2226 	/* Configure PHY and link consistently. */
2227 	if (enable_1394a) {
2228 		clear = 0;
2229 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2230 	} else {
2231 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2232 		set = 0;
2233 	}
2234 	ret = update_phy_reg(ohci, 5, clear, set);
2235 	if (ret < 0)
2236 		return ret;
2237 
2238 	if (enable_1394a)
2239 		offset = OHCI1394_HCControlSet;
2240 	else
2241 		offset = OHCI1394_HCControlClear;
2242 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2243 
2244 	/* Clean up: configuration has been taken care of. */
2245 	reg_write(ohci, OHCI1394_HCControlClear,
2246 		  OHCI1394_HCControl_programPhyEnable);
2247 
2248 	return 0;
2249 }
2250 
2251 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2252 {
2253 	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2254 	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2255 	int reg, i;
2256 
2257 	reg = read_phy_reg(ohci, 2);
2258 	if (reg < 0)
2259 		return reg;
2260 	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2261 		return 0;
2262 
2263 	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2264 		reg = read_paged_phy_reg(ohci, 1, i + 10);
2265 		if (reg < 0)
2266 			return reg;
2267 		if (reg != id[i])
2268 			return 0;
2269 	}
2270 	return 1;
2271 }
2272 
2273 static int ohci_enable(struct fw_card *card,
2274 		       const __be32 *config_rom, size_t length)
2275 {
2276 	struct fw_ohci *ohci = fw_ohci(card);
2277 	u32 lps, version, irqs;
2278 	int i, ret;
2279 
2280 	if (software_reset(ohci)) {
2281 		ohci_err(ohci, "failed to reset ohci card\n");
2282 		return -EBUSY;
2283 	}
2284 
2285 	/*
2286 	 * Now enable LPS, which we need in order to start accessing
2287 	 * most of the registers.  In fact, on some cards (ALI M5251),
2288 	 * accessing registers in the SClk domain without LPS enabled
2289 	 * will lock up the machine.  Wait 50msec to make sure we have
2290 	 * full link enabled.  However, with some cards (well, at least
2291 	 * a JMicron PCIe card), we have to try again sometimes.
2292 	 *
2293 	 * TI TSB82AA2 + TSB81BA3(A) cards signal LPS enabled early but
2294 	 * cannot actually use the phy at that time.  These need tens of
2295 	 * millisecods pause between LPS write and first phy access too.
2296 	 *
2297 	 * But do not wait for 50msec on Agere/LSI cards.  Their phy
2298 	 * arbitration state machine may time out during such a long wait.
2299 	 */
2300 
2301 	reg_write(ohci, OHCI1394_HCControlSet,
2302 		  OHCI1394_HCControl_LPS |
2303 		  OHCI1394_HCControl_postedWriteEnable);
2304 	flush_writes(ohci);
2305 
2306 	if (!(ohci->quirks & QUIRK_PHY_LCTRL_TIMEOUT))
2307 		msleep(50);
2308 
2309 	for (lps = 0, i = 0; !lps && i < 150; i++) {
2310 		msleep(1);
2311 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2312 		      OHCI1394_HCControl_LPS;
2313 	}
2314 
2315 	if (!lps) {
2316 		ohci_err(ohci, "failed to set Link Power Status\n");
2317 		return -EIO;
2318 	}
2319 
2320 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2321 		ret = probe_tsb41ba3d(ohci);
2322 		if (ret < 0)
2323 			return ret;
2324 		if (ret)
2325 			ohci_notice(ohci, "local TSB41BA3D phy\n");
2326 		else
2327 			ohci->quirks &= ~QUIRK_TI_SLLZ059;
2328 	}
2329 
2330 	reg_write(ohci, OHCI1394_HCControlClear,
2331 		  OHCI1394_HCControl_noByteSwapData);
2332 
2333 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2334 	reg_write(ohci, OHCI1394_LinkControlSet,
2335 		  OHCI1394_LinkControl_cycleTimerEnable |
2336 		  OHCI1394_LinkControl_cycleMaster);
2337 
2338 	reg_write(ohci, OHCI1394_ATRetries,
2339 		  OHCI1394_MAX_AT_REQ_RETRIES |
2340 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2341 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2342 		  (200 << 16));
2343 
2344 	ohci->bus_time_running = false;
2345 
2346 	for (i = 0; i < 32; i++)
2347 		if (ohci->ir_context_support & (1 << i))
2348 			reg_write(ohci, OHCI1394_IsoRcvContextControlClear(i),
2349 				  IR_CONTEXT_MULTI_CHANNEL_MODE);
2350 
2351 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2352 	if (version >= OHCI_VERSION_1_1) {
2353 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2354 			  0xfffffffe);
2355 		card->broadcast_channel_auto_allocated = true;
2356 	}
2357 
2358 	/* Get implemented bits of the priority arbitration request counter. */
2359 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2360 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2361 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2362 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2363 
2364 	reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
2365 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2366 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2367 
2368 	ret = configure_1394a_enhancements(ohci);
2369 	if (ret < 0)
2370 		return ret;
2371 
2372 	/* Activate link_on bit and contender bit in our self ID packets.*/
2373 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2374 	if (ret < 0)
2375 		return ret;
2376 
2377 	/*
2378 	 * When the link is not yet enabled, the atomic config rom
2379 	 * update mechanism described below in ohci_set_config_rom()
2380 	 * is not active.  We have to update ConfigRomHeader and
2381 	 * BusOptions manually, and the write to ConfigROMmap takes
2382 	 * effect immediately.  We tie this to the enabling of the
2383 	 * link, so we have a valid config rom before enabling - the
2384 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2385 	 * values before enabling.
2386 	 *
2387 	 * However, when the ConfigROMmap is written, some controllers
2388 	 * always read back quadlets 0 and 2 from the config rom to
2389 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2390 	 * They shouldn't do that in this initial case where the link
2391 	 * isn't enabled.  This means we have to use the same
2392 	 * workaround here, setting the bus header to 0 and then write
2393 	 * the right values in the bus reset tasklet.
2394 	 */
2395 
2396 	if (config_rom) {
2397 		ohci->next_config_rom =
2398 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2399 					   &ohci->next_config_rom_bus,
2400 					   GFP_KERNEL);
2401 		if (ohci->next_config_rom == NULL)
2402 			return -ENOMEM;
2403 
2404 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2405 	} else {
2406 		/*
2407 		 * In the suspend case, config_rom is NULL, which
2408 		 * means that we just reuse the old config rom.
2409 		 */
2410 		ohci->next_config_rom = ohci->config_rom;
2411 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2412 	}
2413 
2414 	ohci->next_header = ohci->next_config_rom[0];
2415 	ohci->next_config_rom[0] = 0;
2416 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2417 	reg_write(ohci, OHCI1394_BusOptions,
2418 		  be32_to_cpu(ohci->next_config_rom[2]));
2419 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2420 
2421 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2422 
2423 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2424 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2425 		OHCI1394_isochTx | OHCI1394_isochRx |
2426 		OHCI1394_postedWriteErr |
2427 		OHCI1394_selfIDComplete |
2428 		OHCI1394_regAccessFail |
2429 		OHCI1394_cycleInconsistent |
2430 		OHCI1394_unrecoverableError |
2431 		OHCI1394_cycleTooLong |
2432 		OHCI1394_masterIntEnable;
2433 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2434 		irqs |= OHCI1394_busReset;
2435 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2436 
2437 	reg_write(ohci, OHCI1394_HCControlSet,
2438 		  OHCI1394_HCControl_linkEnable |
2439 		  OHCI1394_HCControl_BIBimageValid);
2440 
2441 	reg_write(ohci, OHCI1394_LinkControlSet,
2442 		  OHCI1394_LinkControl_rcvSelfID |
2443 		  OHCI1394_LinkControl_rcvPhyPkt);
2444 
2445 	ar_context_run(&ohci->ar_request_ctx);
2446 	ar_context_run(&ohci->ar_response_ctx);
2447 
2448 	flush_writes(ohci);
2449 
2450 	/* We are ready to go, reset bus to finish initialization. */
2451 	fw_schedule_bus_reset(&ohci->card, false, true);
2452 
2453 	return 0;
2454 }
2455 
2456 static int ohci_set_config_rom(struct fw_card *card,
2457 			       const __be32 *config_rom, size_t length)
2458 {
2459 	struct fw_ohci *ohci;
2460 	__be32 *next_config_rom;
2461 	dma_addr_t uninitialized_var(next_config_rom_bus);
2462 
2463 	ohci = fw_ohci(card);
2464 
2465 	/*
2466 	 * When the OHCI controller is enabled, the config rom update
2467 	 * mechanism is a bit tricky, but easy enough to use.  See
2468 	 * section 5.5.6 in the OHCI specification.
2469 	 *
2470 	 * The OHCI controller caches the new config rom address in a
2471 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2472 	 * for the changes to take place.  When the bus reset is
2473 	 * detected, the controller loads the new values for the
2474 	 * ConfigRomHeader and BusOptions registers from the specified
2475 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2476 	 * shadow register. All automatically and atomically.
2477 	 *
2478 	 * Now, there's a twist to this story.  The automatic load of
2479 	 * ConfigRomHeader and BusOptions doesn't honor the
2480 	 * noByteSwapData bit, so with a be32 config rom, the
2481 	 * controller will load be32 values in to these registers
2482 	 * during the atomic update, even on litte endian
2483 	 * architectures.  The workaround we use is to put a 0 in the
2484 	 * header quadlet; 0 is endian agnostic and means that the
2485 	 * config rom isn't ready yet.  In the bus reset tasklet we
2486 	 * then set up the real values for the two registers.
2487 	 *
2488 	 * We use ohci->lock to avoid racing with the code that sets
2489 	 * ohci->next_config_rom to NULL (see bus_reset_work).
2490 	 */
2491 
2492 	next_config_rom =
2493 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2494 				   &next_config_rom_bus, GFP_KERNEL);
2495 	if (next_config_rom == NULL)
2496 		return -ENOMEM;
2497 
2498 	spin_lock_irq(&ohci->lock);
2499 
2500 	/*
2501 	 * If there is not an already pending config_rom update,
2502 	 * push our new allocation into the ohci->next_config_rom
2503 	 * and then mark the local variable as null so that we
2504 	 * won't deallocate the new buffer.
2505 	 *
2506 	 * OTOH, if there is a pending config_rom update, just
2507 	 * use that buffer with the new config_rom data, and
2508 	 * let this routine free the unused DMA allocation.
2509 	 */
2510 
2511 	if (ohci->next_config_rom == NULL) {
2512 		ohci->next_config_rom = next_config_rom;
2513 		ohci->next_config_rom_bus = next_config_rom_bus;
2514 		next_config_rom = NULL;
2515 	}
2516 
2517 	copy_config_rom(ohci->next_config_rom, config_rom, length);
2518 
2519 	ohci->next_header = config_rom[0];
2520 	ohci->next_config_rom[0] = 0;
2521 
2522 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2523 
2524 	spin_unlock_irq(&ohci->lock);
2525 
2526 	/* If we didn't use the DMA allocation, delete it. */
2527 	if (next_config_rom != NULL)
2528 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2529 				  next_config_rom, next_config_rom_bus);
2530 
2531 	/*
2532 	 * Now initiate a bus reset to have the changes take
2533 	 * effect. We clean up the old config rom memory and DMA
2534 	 * mappings in the bus reset tasklet, since the OHCI
2535 	 * controller could need to access it before the bus reset
2536 	 * takes effect.
2537 	 */
2538 
2539 	fw_schedule_bus_reset(&ohci->card, true, true);
2540 
2541 	return 0;
2542 }
2543 
2544 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2545 {
2546 	struct fw_ohci *ohci = fw_ohci(card);
2547 
2548 	at_context_transmit(&ohci->at_request_ctx, packet);
2549 }
2550 
2551 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2552 {
2553 	struct fw_ohci *ohci = fw_ohci(card);
2554 
2555 	at_context_transmit(&ohci->at_response_ctx, packet);
2556 }
2557 
2558 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2559 {
2560 	struct fw_ohci *ohci = fw_ohci(card);
2561 	struct context *ctx = &ohci->at_request_ctx;
2562 	struct driver_data *driver_data = packet->driver_data;
2563 	int ret = -ENOENT;
2564 
2565 	tasklet_disable(&ctx->tasklet);
2566 
2567 	if (packet->ack != 0)
2568 		goto out;
2569 
2570 	if (packet->payload_mapped)
2571 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2572 				 packet->payload_length, DMA_TO_DEVICE);
2573 
2574 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2575 	driver_data->packet = NULL;
2576 	packet->ack = RCODE_CANCELLED;
2577 	packet->callback(packet, &ohci->card, packet->ack);
2578 	ret = 0;
2579  out:
2580 	tasklet_enable(&ctx->tasklet);
2581 
2582 	return ret;
2583 }
2584 
2585 static int ohci_enable_phys_dma(struct fw_card *card,
2586 				int node_id, int generation)
2587 {
2588 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2589 	return 0;
2590 #else
2591 	struct fw_ohci *ohci = fw_ohci(card);
2592 	unsigned long flags;
2593 	int n, ret = 0;
2594 
2595 	/*
2596 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2597 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2598 	 */
2599 
2600 	spin_lock_irqsave(&ohci->lock, flags);
2601 
2602 	if (ohci->generation != generation) {
2603 		ret = -ESTALE;
2604 		goto out;
2605 	}
2606 
2607 	/*
2608 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2609 	 * enabled for _all_ nodes on remote buses.
2610 	 */
2611 
2612 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2613 	if (n < 32)
2614 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2615 	else
2616 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2617 
2618 	flush_writes(ohci);
2619  out:
2620 	spin_unlock_irqrestore(&ohci->lock, flags);
2621 
2622 	return ret;
2623 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2624 }
2625 
2626 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2627 {
2628 	struct fw_ohci *ohci = fw_ohci(card);
2629 	unsigned long flags;
2630 	u32 value;
2631 
2632 	switch (csr_offset) {
2633 	case CSR_STATE_CLEAR:
2634 	case CSR_STATE_SET:
2635 		if (ohci->is_root &&
2636 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2637 		     OHCI1394_LinkControl_cycleMaster))
2638 			value = CSR_STATE_BIT_CMSTR;
2639 		else
2640 			value = 0;
2641 		if (ohci->csr_state_setclear_abdicate)
2642 			value |= CSR_STATE_BIT_ABDICATE;
2643 
2644 		return value;
2645 
2646 	case CSR_NODE_IDS:
2647 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2648 
2649 	case CSR_CYCLE_TIME:
2650 		return get_cycle_time(ohci);
2651 
2652 	case CSR_BUS_TIME:
2653 		/*
2654 		 * We might be called just after the cycle timer has wrapped
2655 		 * around but just before the cycle64Seconds handler, so we
2656 		 * better check here, too, if the bus time needs to be updated.
2657 		 */
2658 		spin_lock_irqsave(&ohci->lock, flags);
2659 		value = update_bus_time(ohci);
2660 		spin_unlock_irqrestore(&ohci->lock, flags);
2661 		return value;
2662 
2663 	case CSR_BUSY_TIMEOUT:
2664 		value = reg_read(ohci, OHCI1394_ATRetries);
2665 		return (value >> 4) & 0x0ffff00f;
2666 
2667 	case CSR_PRIORITY_BUDGET:
2668 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2669 			(ohci->pri_req_max << 8);
2670 
2671 	default:
2672 		WARN_ON(1);
2673 		return 0;
2674 	}
2675 }
2676 
2677 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2678 {
2679 	struct fw_ohci *ohci = fw_ohci(card);
2680 	unsigned long flags;
2681 
2682 	switch (csr_offset) {
2683 	case CSR_STATE_CLEAR:
2684 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2685 			reg_write(ohci, OHCI1394_LinkControlClear,
2686 				  OHCI1394_LinkControl_cycleMaster);
2687 			flush_writes(ohci);
2688 		}
2689 		if (value & CSR_STATE_BIT_ABDICATE)
2690 			ohci->csr_state_setclear_abdicate = false;
2691 		break;
2692 
2693 	case CSR_STATE_SET:
2694 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2695 			reg_write(ohci, OHCI1394_LinkControlSet,
2696 				  OHCI1394_LinkControl_cycleMaster);
2697 			flush_writes(ohci);
2698 		}
2699 		if (value & CSR_STATE_BIT_ABDICATE)
2700 			ohci->csr_state_setclear_abdicate = true;
2701 		break;
2702 
2703 	case CSR_NODE_IDS:
2704 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2705 		flush_writes(ohci);
2706 		break;
2707 
2708 	case CSR_CYCLE_TIME:
2709 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2710 		reg_write(ohci, OHCI1394_IntEventSet,
2711 			  OHCI1394_cycleInconsistent);
2712 		flush_writes(ohci);
2713 		break;
2714 
2715 	case CSR_BUS_TIME:
2716 		spin_lock_irqsave(&ohci->lock, flags);
2717 		ohci->bus_time = (update_bus_time(ohci) & 0x40) |
2718 		                 (value & ~0x7f);
2719 		spin_unlock_irqrestore(&ohci->lock, flags);
2720 		break;
2721 
2722 	case CSR_BUSY_TIMEOUT:
2723 		value = (value & 0xf) | ((value & 0xf) << 4) |
2724 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2725 		reg_write(ohci, OHCI1394_ATRetries, value);
2726 		flush_writes(ohci);
2727 		break;
2728 
2729 	case CSR_PRIORITY_BUDGET:
2730 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2731 		flush_writes(ohci);
2732 		break;
2733 
2734 	default:
2735 		WARN_ON(1);
2736 		break;
2737 	}
2738 }
2739 
2740 static void flush_iso_completions(struct iso_context *ctx)
2741 {
2742 	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2743 			      ctx->header_length, ctx->header,
2744 			      ctx->base.callback_data);
2745 	ctx->header_length = 0;
2746 }
2747 
2748 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2749 {
2750 	u32 *ctx_hdr;
2751 
2752 	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE) {
2753 		if (ctx->base.drop_overflow_headers)
2754 			return;
2755 		flush_iso_completions(ctx);
2756 	}
2757 
2758 	ctx_hdr = ctx->header + ctx->header_length;
2759 	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2760 
2761 	/*
2762 	 * The two iso header quadlets are byteswapped to little
2763 	 * endian by the controller, but we want to present them
2764 	 * as big endian for consistency with the bus endianness.
2765 	 */
2766 	if (ctx->base.header_size > 0)
2767 		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2768 	if (ctx->base.header_size > 4)
2769 		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2770 	if (ctx->base.header_size > 8)
2771 		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2772 	ctx->header_length += ctx->base.header_size;
2773 }
2774 
2775 static int handle_ir_packet_per_buffer(struct context *context,
2776 				       struct descriptor *d,
2777 				       struct descriptor *last)
2778 {
2779 	struct iso_context *ctx =
2780 		container_of(context, struct iso_context, context);
2781 	struct descriptor *pd;
2782 	u32 buffer_dma;
2783 
2784 	for (pd = d; pd <= last; pd++)
2785 		if (pd->transfer_status)
2786 			break;
2787 	if (pd > last)
2788 		/* Descriptor(s) not done yet, stop iteration */
2789 		return 0;
2790 
2791 	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2792 		d++;
2793 		buffer_dma = le32_to_cpu(d->data_address);
2794 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2795 					      buffer_dma & PAGE_MASK,
2796 					      buffer_dma & ~PAGE_MASK,
2797 					      le16_to_cpu(d->req_count),
2798 					      DMA_FROM_DEVICE);
2799 	}
2800 
2801 	copy_iso_headers(ctx, (u32 *) (last + 1));
2802 
2803 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2804 		flush_iso_completions(ctx);
2805 
2806 	return 1;
2807 }
2808 
2809 /* d == last because each descriptor block is only a single descriptor. */
2810 static int handle_ir_buffer_fill(struct context *context,
2811 				 struct descriptor *d,
2812 				 struct descriptor *last)
2813 {
2814 	struct iso_context *ctx =
2815 		container_of(context, struct iso_context, context);
2816 	unsigned int req_count, res_count, completed;
2817 	u32 buffer_dma;
2818 
2819 	req_count = le16_to_cpu(last->req_count);
2820 	res_count = le16_to_cpu(ACCESS_ONCE(last->res_count));
2821 	completed = req_count - res_count;
2822 	buffer_dma = le32_to_cpu(last->data_address);
2823 
2824 	if (completed > 0) {
2825 		ctx->mc_buffer_bus = buffer_dma;
2826 		ctx->mc_completed = completed;
2827 	}
2828 
2829 	if (res_count != 0)
2830 		/* Descriptor(s) not done yet, stop iteration */
2831 		return 0;
2832 
2833 	dma_sync_single_range_for_cpu(context->ohci->card.device,
2834 				      buffer_dma & PAGE_MASK,
2835 				      buffer_dma & ~PAGE_MASK,
2836 				      completed, DMA_FROM_DEVICE);
2837 
2838 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2839 		ctx->base.callback.mc(&ctx->base,
2840 				      buffer_dma + completed,
2841 				      ctx->base.callback_data);
2842 		ctx->mc_completed = 0;
2843 	}
2844 
2845 	return 1;
2846 }
2847 
2848 static void flush_ir_buffer_fill(struct iso_context *ctx)
2849 {
2850 	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
2851 				      ctx->mc_buffer_bus & PAGE_MASK,
2852 				      ctx->mc_buffer_bus & ~PAGE_MASK,
2853 				      ctx->mc_completed, DMA_FROM_DEVICE);
2854 
2855 	ctx->base.callback.mc(&ctx->base,
2856 			      ctx->mc_buffer_bus + ctx->mc_completed,
2857 			      ctx->base.callback_data);
2858 	ctx->mc_completed = 0;
2859 }
2860 
2861 static inline void sync_it_packet_for_cpu(struct context *context,
2862 					  struct descriptor *pd)
2863 {
2864 	__le16 control;
2865 	u32 buffer_dma;
2866 
2867 	/* only packets beginning with OUTPUT_MORE* have data buffers */
2868 	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2869 		return;
2870 
2871 	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
2872 	pd += 2;
2873 
2874 	/*
2875 	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
2876 	 * data buffer is in the context program's coherent page and must not
2877 	 * be synced.
2878 	 */
2879 	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
2880 	    (context->current_bus          & PAGE_MASK)) {
2881 		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2882 			return;
2883 		pd++;
2884 	}
2885 
2886 	do {
2887 		buffer_dma = le32_to_cpu(pd->data_address);
2888 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2889 					      buffer_dma & PAGE_MASK,
2890 					      buffer_dma & ~PAGE_MASK,
2891 					      le16_to_cpu(pd->req_count),
2892 					      DMA_TO_DEVICE);
2893 		control = pd->control;
2894 		pd++;
2895 	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
2896 }
2897 
2898 static int handle_it_packet(struct context *context,
2899 			    struct descriptor *d,
2900 			    struct descriptor *last)
2901 {
2902 	struct iso_context *ctx =
2903 		container_of(context, struct iso_context, context);
2904 	struct descriptor *pd;
2905 	__be32 *ctx_hdr;
2906 
2907 	for (pd = d; pd <= last; pd++)
2908 		if (pd->transfer_status)
2909 			break;
2910 	if (pd > last)
2911 		/* Descriptor(s) not done yet, stop iteration */
2912 		return 0;
2913 
2914 	sync_it_packet_for_cpu(context, d);
2915 
2916 	if (ctx->header_length + 4 > PAGE_SIZE) {
2917 		if (ctx->base.drop_overflow_headers)
2918 			return 1;
2919 		flush_iso_completions(ctx);
2920 	}
2921 
2922 	ctx_hdr = ctx->header + ctx->header_length;
2923 	ctx->last_timestamp = le16_to_cpu(last->res_count);
2924 	/* Present this value as big-endian to match the receive code */
2925 	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
2926 			       le16_to_cpu(pd->res_count));
2927 	ctx->header_length += 4;
2928 
2929 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2930 		flush_iso_completions(ctx);
2931 
2932 	return 1;
2933 }
2934 
2935 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2936 {
2937 	u32 hi = channels >> 32, lo = channels;
2938 
2939 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2940 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2941 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2942 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2943 	mmiowb();
2944 	ohci->mc_channels = channels;
2945 }
2946 
2947 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2948 				int type, int channel, size_t header_size)
2949 {
2950 	struct fw_ohci *ohci = fw_ohci(card);
2951 	struct iso_context *uninitialized_var(ctx);
2952 	descriptor_callback_t uninitialized_var(callback);
2953 	u64 *uninitialized_var(channels);
2954 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2955 	int index, ret = -EBUSY;
2956 
2957 	spin_lock_irq(&ohci->lock);
2958 
2959 	switch (type) {
2960 	case FW_ISO_CONTEXT_TRANSMIT:
2961 		mask     = &ohci->it_context_mask;
2962 		callback = handle_it_packet;
2963 		index    = ffs(*mask) - 1;
2964 		if (index >= 0) {
2965 			*mask &= ~(1 << index);
2966 			regs = OHCI1394_IsoXmitContextBase(index);
2967 			ctx  = &ohci->it_context_list[index];
2968 		}
2969 		break;
2970 
2971 	case FW_ISO_CONTEXT_RECEIVE:
2972 		channels = &ohci->ir_context_channels;
2973 		mask     = &ohci->ir_context_mask;
2974 		callback = handle_ir_packet_per_buffer;
2975 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2976 		if (index >= 0) {
2977 			*channels &= ~(1ULL << channel);
2978 			*mask     &= ~(1 << index);
2979 			regs = OHCI1394_IsoRcvContextBase(index);
2980 			ctx  = &ohci->ir_context_list[index];
2981 		}
2982 		break;
2983 
2984 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2985 		mask     = &ohci->ir_context_mask;
2986 		callback = handle_ir_buffer_fill;
2987 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2988 		if (index >= 0) {
2989 			ohci->mc_allocated = true;
2990 			*mask &= ~(1 << index);
2991 			regs = OHCI1394_IsoRcvContextBase(index);
2992 			ctx  = &ohci->ir_context_list[index];
2993 		}
2994 		break;
2995 
2996 	default:
2997 		index = -1;
2998 		ret = -ENOSYS;
2999 	}
3000 
3001 	spin_unlock_irq(&ohci->lock);
3002 
3003 	if (index < 0)
3004 		return ERR_PTR(ret);
3005 
3006 	memset(ctx, 0, sizeof(*ctx));
3007 	ctx->header_length = 0;
3008 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
3009 	if (ctx->header == NULL) {
3010 		ret = -ENOMEM;
3011 		goto out;
3012 	}
3013 	ret = context_init(&ctx->context, ohci, regs, callback);
3014 	if (ret < 0)
3015 		goto out_with_header;
3016 
3017 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
3018 		set_multichannel_mask(ohci, 0);
3019 		ctx->mc_completed = 0;
3020 	}
3021 
3022 	return &ctx->base;
3023 
3024  out_with_header:
3025 	free_page((unsigned long)ctx->header);
3026  out:
3027 	spin_lock_irq(&ohci->lock);
3028 
3029 	switch (type) {
3030 	case FW_ISO_CONTEXT_RECEIVE:
3031 		*channels |= 1ULL << channel;
3032 		break;
3033 
3034 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3035 		ohci->mc_allocated = false;
3036 		break;
3037 	}
3038 	*mask |= 1 << index;
3039 
3040 	spin_unlock_irq(&ohci->lock);
3041 
3042 	return ERR_PTR(ret);
3043 }
3044 
3045 static int ohci_start_iso(struct fw_iso_context *base,
3046 			  s32 cycle, u32 sync, u32 tags)
3047 {
3048 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3049 	struct fw_ohci *ohci = ctx->context.ohci;
3050 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
3051 	int index;
3052 
3053 	/* the controller cannot start without any queued packets */
3054 	if (ctx->context.last->branch_address == 0)
3055 		return -ENODATA;
3056 
3057 	switch (ctx->base.type) {
3058 	case FW_ISO_CONTEXT_TRANSMIT:
3059 		index = ctx - ohci->it_context_list;
3060 		match = 0;
3061 		if (cycle >= 0)
3062 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3063 				(cycle & 0x7fff) << 16;
3064 
3065 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3066 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3067 		context_run(&ctx->context, match);
3068 		break;
3069 
3070 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3071 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3072 		/* fall through */
3073 	case FW_ISO_CONTEXT_RECEIVE:
3074 		index = ctx - ohci->ir_context_list;
3075 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
3076 		if (cycle >= 0) {
3077 			match |= (cycle & 0x07fff) << 12;
3078 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3079 		}
3080 
3081 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3082 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3083 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3084 		context_run(&ctx->context, control);
3085 
3086 		ctx->sync = sync;
3087 		ctx->tags = tags;
3088 
3089 		break;
3090 	}
3091 
3092 	return 0;
3093 }
3094 
3095 static int ohci_stop_iso(struct fw_iso_context *base)
3096 {
3097 	struct fw_ohci *ohci = fw_ohci(base->card);
3098 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3099 	int index;
3100 
3101 	switch (ctx->base.type) {
3102 	case FW_ISO_CONTEXT_TRANSMIT:
3103 		index = ctx - ohci->it_context_list;
3104 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3105 		break;
3106 
3107 	case FW_ISO_CONTEXT_RECEIVE:
3108 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3109 		index = ctx - ohci->ir_context_list;
3110 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3111 		break;
3112 	}
3113 	flush_writes(ohci);
3114 	context_stop(&ctx->context);
3115 	tasklet_kill(&ctx->context.tasklet);
3116 
3117 	return 0;
3118 }
3119 
3120 static void ohci_free_iso_context(struct fw_iso_context *base)
3121 {
3122 	struct fw_ohci *ohci = fw_ohci(base->card);
3123 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3124 	unsigned long flags;
3125 	int index;
3126 
3127 	ohci_stop_iso(base);
3128 	context_release(&ctx->context);
3129 	free_page((unsigned long)ctx->header);
3130 
3131 	spin_lock_irqsave(&ohci->lock, flags);
3132 
3133 	switch (base->type) {
3134 	case FW_ISO_CONTEXT_TRANSMIT:
3135 		index = ctx - ohci->it_context_list;
3136 		ohci->it_context_mask |= 1 << index;
3137 		break;
3138 
3139 	case FW_ISO_CONTEXT_RECEIVE:
3140 		index = ctx - ohci->ir_context_list;
3141 		ohci->ir_context_mask |= 1 << index;
3142 		ohci->ir_context_channels |= 1ULL << base->channel;
3143 		break;
3144 
3145 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3146 		index = ctx - ohci->ir_context_list;
3147 		ohci->ir_context_mask |= 1 << index;
3148 		ohci->ir_context_channels |= ohci->mc_channels;
3149 		ohci->mc_channels = 0;
3150 		ohci->mc_allocated = false;
3151 		break;
3152 	}
3153 
3154 	spin_unlock_irqrestore(&ohci->lock, flags);
3155 }
3156 
3157 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3158 {
3159 	struct fw_ohci *ohci = fw_ohci(base->card);
3160 	unsigned long flags;
3161 	int ret;
3162 
3163 	switch (base->type) {
3164 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3165 
3166 		spin_lock_irqsave(&ohci->lock, flags);
3167 
3168 		/* Don't allow multichannel to grab other contexts' channels. */
3169 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3170 			*channels = ohci->ir_context_channels;
3171 			ret = -EBUSY;
3172 		} else {
3173 			set_multichannel_mask(ohci, *channels);
3174 			ret = 0;
3175 		}
3176 
3177 		spin_unlock_irqrestore(&ohci->lock, flags);
3178 
3179 		break;
3180 	default:
3181 		ret = -EINVAL;
3182 	}
3183 
3184 	return ret;
3185 }
3186 
3187 #ifdef CONFIG_PM
3188 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3189 {
3190 	int i;
3191 	struct iso_context *ctx;
3192 
3193 	for (i = 0 ; i < ohci->n_ir ; i++) {
3194 		ctx = &ohci->ir_context_list[i];
3195 		if (ctx->context.running)
3196 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3197 	}
3198 
3199 	for (i = 0 ; i < ohci->n_it ; i++) {
3200 		ctx = &ohci->it_context_list[i];
3201 		if (ctx->context.running)
3202 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3203 	}
3204 }
3205 #endif
3206 
3207 static int queue_iso_transmit(struct iso_context *ctx,
3208 			      struct fw_iso_packet *packet,
3209 			      struct fw_iso_buffer *buffer,
3210 			      unsigned long payload)
3211 {
3212 	struct descriptor *d, *last, *pd;
3213 	struct fw_iso_packet *p;
3214 	__le32 *header;
3215 	dma_addr_t d_bus, page_bus;
3216 	u32 z, header_z, payload_z, irq;
3217 	u32 payload_index, payload_end_index, next_page_index;
3218 	int page, end_page, i, length, offset;
3219 
3220 	p = packet;
3221 	payload_index = payload;
3222 
3223 	if (p->skip)
3224 		z = 1;
3225 	else
3226 		z = 2;
3227 	if (p->header_length > 0)
3228 		z++;
3229 
3230 	/* Determine the first page the payload isn't contained in. */
3231 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3232 	if (p->payload_length > 0)
3233 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
3234 	else
3235 		payload_z = 0;
3236 
3237 	z += payload_z;
3238 
3239 	/* Get header size in number of descriptors. */
3240 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3241 
3242 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3243 	if (d == NULL)
3244 		return -ENOMEM;
3245 
3246 	if (!p->skip) {
3247 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3248 		d[0].req_count = cpu_to_le16(8);
3249 		/*
3250 		 * Link the skip address to this descriptor itself.  This causes
3251 		 * a context to skip a cycle whenever lost cycles or FIFO
3252 		 * overruns occur, without dropping the data.  The application
3253 		 * should then decide whether this is an error condition or not.
3254 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
3255 		 */
3256 		d[0].branch_address = cpu_to_le32(d_bus | z);
3257 
3258 		header = (__le32 *) &d[1];
3259 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
3260 					IT_HEADER_TAG(p->tag) |
3261 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
3262 					IT_HEADER_CHANNEL(ctx->base.channel) |
3263 					IT_HEADER_SPEED(ctx->base.speed));
3264 		header[1] =
3265 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
3266 							  p->payload_length));
3267 	}
3268 
3269 	if (p->header_length > 0) {
3270 		d[2].req_count    = cpu_to_le16(p->header_length);
3271 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3272 		memcpy(&d[z], p->header, p->header_length);
3273 	}
3274 
3275 	pd = d + z - payload_z;
3276 	payload_end_index = payload_index + p->payload_length;
3277 	for (i = 0; i < payload_z; i++) {
3278 		page               = payload_index >> PAGE_SHIFT;
3279 		offset             = payload_index & ~PAGE_MASK;
3280 		next_page_index    = (page + 1) << PAGE_SHIFT;
3281 		length             =
3282 			min(next_page_index, payload_end_index) - payload_index;
3283 		pd[i].req_count    = cpu_to_le16(length);
3284 
3285 		page_bus = page_private(buffer->pages[page]);
3286 		pd[i].data_address = cpu_to_le32(page_bus + offset);
3287 
3288 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3289 						 page_bus, offset, length,
3290 						 DMA_TO_DEVICE);
3291 
3292 		payload_index += length;
3293 	}
3294 
3295 	if (p->interrupt)
3296 		irq = DESCRIPTOR_IRQ_ALWAYS;
3297 	else
3298 		irq = DESCRIPTOR_NO_IRQ;
3299 
3300 	last = z == 2 ? d : d + z - 1;
3301 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3302 				     DESCRIPTOR_STATUS |
3303 				     DESCRIPTOR_BRANCH_ALWAYS |
3304 				     irq);
3305 
3306 	context_append(&ctx->context, d, z, header_z);
3307 
3308 	return 0;
3309 }
3310 
3311 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3312 				       struct fw_iso_packet *packet,
3313 				       struct fw_iso_buffer *buffer,
3314 				       unsigned long payload)
3315 {
3316 	struct device *device = ctx->context.ohci->card.device;
3317 	struct descriptor *d, *pd;
3318 	dma_addr_t d_bus, page_bus;
3319 	u32 z, header_z, rest;
3320 	int i, j, length;
3321 	int page, offset, packet_count, header_size, payload_per_buffer;
3322 
3323 	/*
3324 	 * The OHCI controller puts the isochronous header and trailer in the
3325 	 * buffer, so we need at least 8 bytes.
3326 	 */
3327 	packet_count = packet->header_length / ctx->base.header_size;
3328 	header_size  = max(ctx->base.header_size, (size_t)8);
3329 
3330 	/* Get header size in number of descriptors. */
3331 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3332 	page     = payload >> PAGE_SHIFT;
3333 	offset   = payload & ~PAGE_MASK;
3334 	payload_per_buffer = packet->payload_length / packet_count;
3335 
3336 	for (i = 0; i < packet_count; i++) {
3337 		/* d points to the header descriptor */
3338 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3339 		d = context_get_descriptors(&ctx->context,
3340 				z + header_z, &d_bus);
3341 		if (d == NULL)
3342 			return -ENOMEM;
3343 
3344 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3345 					      DESCRIPTOR_INPUT_MORE);
3346 		if (packet->skip && i == 0)
3347 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3348 		d->req_count    = cpu_to_le16(header_size);
3349 		d->res_count    = d->req_count;
3350 		d->transfer_status = 0;
3351 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3352 
3353 		rest = payload_per_buffer;
3354 		pd = d;
3355 		for (j = 1; j < z; j++) {
3356 			pd++;
3357 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3358 						  DESCRIPTOR_INPUT_MORE);
3359 
3360 			if (offset + rest < PAGE_SIZE)
3361 				length = rest;
3362 			else
3363 				length = PAGE_SIZE - offset;
3364 			pd->req_count = cpu_to_le16(length);
3365 			pd->res_count = pd->req_count;
3366 			pd->transfer_status = 0;
3367 
3368 			page_bus = page_private(buffer->pages[page]);
3369 			pd->data_address = cpu_to_le32(page_bus + offset);
3370 
3371 			dma_sync_single_range_for_device(device, page_bus,
3372 							 offset, length,
3373 							 DMA_FROM_DEVICE);
3374 
3375 			offset = (offset + length) & ~PAGE_MASK;
3376 			rest -= length;
3377 			if (offset == 0)
3378 				page++;
3379 		}
3380 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3381 					  DESCRIPTOR_INPUT_LAST |
3382 					  DESCRIPTOR_BRANCH_ALWAYS);
3383 		if (packet->interrupt && i == packet_count - 1)
3384 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3385 
3386 		context_append(&ctx->context, d, z, header_z);
3387 	}
3388 
3389 	return 0;
3390 }
3391 
3392 static int queue_iso_buffer_fill(struct iso_context *ctx,
3393 				 struct fw_iso_packet *packet,
3394 				 struct fw_iso_buffer *buffer,
3395 				 unsigned long payload)
3396 {
3397 	struct descriptor *d;
3398 	dma_addr_t d_bus, page_bus;
3399 	int page, offset, rest, z, i, length;
3400 
3401 	page   = payload >> PAGE_SHIFT;
3402 	offset = payload & ~PAGE_MASK;
3403 	rest   = packet->payload_length;
3404 
3405 	/* We need one descriptor for each page in the buffer. */
3406 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3407 
3408 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3409 		return -EFAULT;
3410 
3411 	for (i = 0; i < z; i++) {
3412 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3413 		if (d == NULL)
3414 			return -ENOMEM;
3415 
3416 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3417 					 DESCRIPTOR_BRANCH_ALWAYS);
3418 		if (packet->skip && i == 0)
3419 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3420 		if (packet->interrupt && i == z - 1)
3421 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3422 
3423 		if (offset + rest < PAGE_SIZE)
3424 			length = rest;
3425 		else
3426 			length = PAGE_SIZE - offset;
3427 		d->req_count = cpu_to_le16(length);
3428 		d->res_count = d->req_count;
3429 		d->transfer_status = 0;
3430 
3431 		page_bus = page_private(buffer->pages[page]);
3432 		d->data_address = cpu_to_le32(page_bus + offset);
3433 
3434 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3435 						 page_bus, offset, length,
3436 						 DMA_FROM_DEVICE);
3437 
3438 		rest -= length;
3439 		offset = 0;
3440 		page++;
3441 
3442 		context_append(&ctx->context, d, 1, 0);
3443 	}
3444 
3445 	return 0;
3446 }
3447 
3448 static int ohci_queue_iso(struct fw_iso_context *base,
3449 			  struct fw_iso_packet *packet,
3450 			  struct fw_iso_buffer *buffer,
3451 			  unsigned long payload)
3452 {
3453 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3454 	unsigned long flags;
3455 	int ret = -ENOSYS;
3456 
3457 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3458 	switch (base->type) {
3459 	case FW_ISO_CONTEXT_TRANSMIT:
3460 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
3461 		break;
3462 	case FW_ISO_CONTEXT_RECEIVE:
3463 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3464 		break;
3465 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3466 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3467 		break;
3468 	}
3469 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3470 
3471 	return ret;
3472 }
3473 
3474 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3475 {
3476 	struct context *ctx =
3477 			&container_of(base, struct iso_context, base)->context;
3478 
3479 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3480 }
3481 
3482 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3483 {
3484 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3485 	int ret = 0;
3486 
3487 	tasklet_disable(&ctx->context.tasklet);
3488 
3489 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3490 		context_tasklet((unsigned long)&ctx->context);
3491 
3492 		switch (base->type) {
3493 		case FW_ISO_CONTEXT_TRANSMIT:
3494 		case FW_ISO_CONTEXT_RECEIVE:
3495 			if (ctx->header_length != 0)
3496 				flush_iso_completions(ctx);
3497 			break;
3498 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3499 			if (ctx->mc_completed != 0)
3500 				flush_ir_buffer_fill(ctx);
3501 			break;
3502 		default:
3503 			ret = -ENOSYS;
3504 		}
3505 
3506 		clear_bit_unlock(0, &ctx->flushing_completions);
3507 		smp_mb__after_clear_bit();
3508 	}
3509 
3510 	tasklet_enable(&ctx->context.tasklet);
3511 
3512 	return ret;
3513 }
3514 
3515 static const struct fw_card_driver ohci_driver = {
3516 	.enable			= ohci_enable,
3517 	.read_phy_reg		= ohci_read_phy_reg,
3518 	.update_phy_reg		= ohci_update_phy_reg,
3519 	.set_config_rom		= ohci_set_config_rom,
3520 	.send_request		= ohci_send_request,
3521 	.send_response		= ohci_send_response,
3522 	.cancel_packet		= ohci_cancel_packet,
3523 	.enable_phys_dma	= ohci_enable_phys_dma,
3524 	.read_csr		= ohci_read_csr,
3525 	.write_csr		= ohci_write_csr,
3526 
3527 	.allocate_iso_context	= ohci_allocate_iso_context,
3528 	.free_iso_context	= ohci_free_iso_context,
3529 	.set_iso_channels	= ohci_set_iso_channels,
3530 	.queue_iso		= ohci_queue_iso,
3531 	.flush_queue_iso	= ohci_flush_queue_iso,
3532 	.flush_iso_completions	= ohci_flush_iso_completions,
3533 	.start_iso		= ohci_start_iso,
3534 	.stop_iso		= ohci_stop_iso,
3535 };
3536 
3537 #ifdef CONFIG_PPC_PMAC
3538 static void pmac_ohci_on(struct pci_dev *dev)
3539 {
3540 	if (machine_is(powermac)) {
3541 		struct device_node *ofn = pci_device_to_OF_node(dev);
3542 
3543 		if (ofn) {
3544 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3545 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3546 		}
3547 	}
3548 }
3549 
3550 static void pmac_ohci_off(struct pci_dev *dev)
3551 {
3552 	if (machine_is(powermac)) {
3553 		struct device_node *ofn = pci_device_to_OF_node(dev);
3554 
3555 		if (ofn) {
3556 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3557 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3558 		}
3559 	}
3560 }
3561 #else
3562 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3563 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3564 #endif /* CONFIG_PPC_PMAC */
3565 
3566 static int pci_probe(struct pci_dev *dev,
3567 			       const struct pci_device_id *ent)
3568 {
3569 	struct fw_ohci *ohci;
3570 	u32 bus_options, max_receive, link_speed, version;
3571 	u64 guid;
3572 	int i, err;
3573 	size_t size;
3574 
3575 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3576 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3577 		return -ENOSYS;
3578 	}
3579 
3580 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3581 	if (ohci == NULL) {
3582 		err = -ENOMEM;
3583 		goto fail;
3584 	}
3585 
3586 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3587 
3588 	pmac_ohci_on(dev);
3589 
3590 	err = pci_enable_device(dev);
3591 	if (err) {
3592 		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3593 		goto fail_free;
3594 	}
3595 
3596 	pci_set_master(dev);
3597 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3598 	pci_set_drvdata(dev, ohci);
3599 
3600 	spin_lock_init(&ohci->lock);
3601 	mutex_init(&ohci->phy_reg_mutex);
3602 
3603 	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3604 
3605 	if (!(pci_resource_flags(dev, 0) & IORESOURCE_MEM) ||
3606 	    pci_resource_len(dev, 0) < OHCI1394_REGISTER_SIZE) {
3607 		ohci_err(ohci, "invalid MMIO resource\n");
3608 		err = -ENXIO;
3609 		goto fail_disable;
3610 	}
3611 
3612 	err = pci_request_region(dev, 0, ohci_driver_name);
3613 	if (err) {
3614 		ohci_err(ohci, "MMIO resource unavailable\n");
3615 		goto fail_disable;
3616 	}
3617 
3618 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3619 	if (ohci->registers == NULL) {
3620 		ohci_err(ohci, "failed to remap registers\n");
3621 		err = -ENXIO;
3622 		goto fail_iomem;
3623 	}
3624 
3625 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3626 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3627 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3628 		     ohci_quirks[i].device == dev->device) &&
3629 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3630 		     ohci_quirks[i].revision >= dev->revision)) {
3631 			ohci->quirks = ohci_quirks[i].flags;
3632 			break;
3633 		}
3634 	if (param_quirks)
3635 		ohci->quirks = param_quirks;
3636 
3637 	/*
3638 	 * Because dma_alloc_coherent() allocates at least one page,
3639 	 * we save space by using a common buffer for the AR request/
3640 	 * response descriptors and the self IDs buffer.
3641 	 */
3642 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3643 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3644 	ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3645 					       PAGE_SIZE,
3646 					       &ohci->misc_buffer_bus,
3647 					       GFP_KERNEL);
3648 	if (!ohci->misc_buffer) {
3649 		err = -ENOMEM;
3650 		goto fail_iounmap;
3651 	}
3652 
3653 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3654 			      OHCI1394_AsReqRcvContextControlSet);
3655 	if (err < 0)
3656 		goto fail_misc_buf;
3657 
3658 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3659 			      OHCI1394_AsRspRcvContextControlSet);
3660 	if (err < 0)
3661 		goto fail_arreq_ctx;
3662 
3663 	err = context_init(&ohci->at_request_ctx, ohci,
3664 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3665 	if (err < 0)
3666 		goto fail_arrsp_ctx;
3667 
3668 	err = context_init(&ohci->at_response_ctx, ohci,
3669 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3670 	if (err < 0)
3671 		goto fail_atreq_ctx;
3672 
3673 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3674 	ohci->ir_context_channels = ~0ULL;
3675 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3676 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3677 	ohci->ir_context_mask = ohci->ir_context_support;
3678 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3679 	size = sizeof(struct iso_context) * ohci->n_ir;
3680 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3681 
3682 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3683 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3684 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3685 	ohci->it_context_mask = ohci->it_context_support;
3686 	ohci->n_it = hweight32(ohci->it_context_mask);
3687 	size = sizeof(struct iso_context) * ohci->n_it;
3688 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3689 
3690 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3691 		err = -ENOMEM;
3692 		goto fail_contexts;
3693 	}
3694 
3695 	ohci->self_id_cpu = ohci->misc_buffer     + PAGE_SIZE/2;
3696 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3697 
3698 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3699 	max_receive = (bus_options >> 12) & 0xf;
3700 	link_speed = bus_options & 0x7;
3701 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3702 		reg_read(ohci, OHCI1394_GUIDLo);
3703 
3704 	if (!(ohci->quirks & QUIRK_NO_MSI))
3705 		pci_enable_msi(dev);
3706 	if (request_irq(dev->irq, irq_handler,
3707 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
3708 			ohci_driver_name, ohci)) {
3709 		ohci_err(ohci, "failed to allocate interrupt %d\n", dev->irq);
3710 		err = -EIO;
3711 		goto fail_msi;
3712 	}
3713 
3714 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3715 	if (err)
3716 		goto fail_irq;
3717 
3718 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3719 	ohci_notice(ohci,
3720 		    "added OHCI v%x.%x device as card %d, "
3721 		    "%d IR + %d IT contexts, quirks 0x%x\n",
3722 		    version >> 16, version & 0xff, ohci->card.index,
3723 		    ohci->n_ir, ohci->n_it, ohci->quirks);
3724 
3725 	return 0;
3726 
3727  fail_irq:
3728 	free_irq(dev->irq, ohci);
3729  fail_msi:
3730 	pci_disable_msi(dev);
3731  fail_contexts:
3732 	kfree(ohci->ir_context_list);
3733 	kfree(ohci->it_context_list);
3734 	context_release(&ohci->at_response_ctx);
3735  fail_atreq_ctx:
3736 	context_release(&ohci->at_request_ctx);
3737  fail_arrsp_ctx:
3738 	ar_context_release(&ohci->ar_response_ctx);
3739  fail_arreq_ctx:
3740 	ar_context_release(&ohci->ar_request_ctx);
3741  fail_misc_buf:
3742 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3743 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3744  fail_iounmap:
3745 	pci_iounmap(dev, ohci->registers);
3746  fail_iomem:
3747 	pci_release_region(dev, 0);
3748  fail_disable:
3749 	pci_disable_device(dev);
3750  fail_free:
3751 	kfree(ohci);
3752 	pmac_ohci_off(dev);
3753  fail:
3754 	return err;
3755 }
3756 
3757 static void pci_remove(struct pci_dev *dev)
3758 {
3759 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3760 
3761 	/*
3762 	 * If the removal is happening from the suspend state, LPS won't be
3763 	 * enabled and host registers (eg., IntMaskClear) won't be accessible.
3764 	 */
3765 	if (reg_read(ohci, OHCI1394_HCControlSet) & OHCI1394_HCControl_LPS) {
3766 		reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3767 		flush_writes(ohci);
3768 	}
3769 	cancel_work_sync(&ohci->bus_reset_work);
3770 	fw_core_remove_card(&ohci->card);
3771 
3772 	/*
3773 	 * FIXME: Fail all pending packets here, now that the upper
3774 	 * layers can't queue any more.
3775 	 */
3776 
3777 	software_reset(ohci);
3778 	free_irq(dev->irq, ohci);
3779 
3780 	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3781 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3782 				  ohci->next_config_rom, ohci->next_config_rom_bus);
3783 	if (ohci->config_rom)
3784 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3785 				  ohci->config_rom, ohci->config_rom_bus);
3786 	ar_context_release(&ohci->ar_request_ctx);
3787 	ar_context_release(&ohci->ar_response_ctx);
3788 	dma_free_coherent(ohci->card.device, PAGE_SIZE,
3789 			  ohci->misc_buffer, ohci->misc_buffer_bus);
3790 	context_release(&ohci->at_request_ctx);
3791 	context_release(&ohci->at_response_ctx);
3792 	kfree(ohci->it_context_list);
3793 	kfree(ohci->ir_context_list);
3794 	pci_disable_msi(dev);
3795 	pci_iounmap(dev, ohci->registers);
3796 	pci_release_region(dev, 0);
3797 	pci_disable_device(dev);
3798 	kfree(ohci);
3799 	pmac_ohci_off(dev);
3800 
3801 	dev_notice(&dev->dev, "removed fw-ohci device\n");
3802 }
3803 
3804 #ifdef CONFIG_PM
3805 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3806 {
3807 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3808 	int err;
3809 
3810 	software_reset(ohci);
3811 	err = pci_save_state(dev);
3812 	if (err) {
3813 		ohci_err(ohci, "pci_save_state failed\n");
3814 		return err;
3815 	}
3816 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3817 	if (err)
3818 		ohci_err(ohci, "pci_set_power_state failed with %d\n", err);
3819 	pmac_ohci_off(dev);
3820 
3821 	return 0;
3822 }
3823 
3824 static int pci_resume(struct pci_dev *dev)
3825 {
3826 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3827 	int err;
3828 
3829 	pmac_ohci_on(dev);
3830 	pci_set_power_state(dev, PCI_D0);
3831 	pci_restore_state(dev);
3832 	err = pci_enable_device(dev);
3833 	if (err) {
3834 		ohci_err(ohci, "pci_enable_device failed\n");
3835 		return err;
3836 	}
3837 
3838 	/* Some systems don't setup GUID register on resume from ram  */
3839 	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3840 					!reg_read(ohci, OHCI1394_GUIDHi)) {
3841 		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3842 		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3843 	}
3844 
3845 	err = ohci_enable(&ohci->card, NULL, 0);
3846 	if (err)
3847 		return err;
3848 
3849 	ohci_resume_iso_dma(ohci);
3850 
3851 	return 0;
3852 }
3853 #endif
3854 
3855 static const struct pci_device_id pci_table[] = {
3856 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3857 	{ }
3858 };
3859 
3860 MODULE_DEVICE_TABLE(pci, pci_table);
3861 
3862 static struct pci_driver fw_ohci_pci_driver = {
3863 	.name		= ohci_driver_name,
3864 	.id_table	= pci_table,
3865 	.probe		= pci_probe,
3866 	.remove		= pci_remove,
3867 #ifdef CONFIG_PM
3868 	.resume		= pci_resume,
3869 	.suspend	= pci_suspend,
3870 #endif
3871 };
3872 
3873 module_pci_driver(fw_ohci_pci_driver);
3874 
3875 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3876 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3877 MODULE_LICENSE("GPL");
3878 
3879 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3880 MODULE_ALIAS("ohci1394");
3881