xref: /linux/drivers/firewire/ohci.c (revision 37cb8e1f8e10c6e9bd2a1b95cdda0620a21b0551)
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;
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 struct workqueue_struct *selfid_workqueue;
246 
247 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
248 {
249 	return container_of(card, struct fw_ohci, card);
250 }
251 
252 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
253 #define IR_CONTEXT_BUFFER_FILL		0x80000000
254 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
255 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
256 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
257 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
258 
259 #define CONTEXT_RUN	0x8000
260 #define CONTEXT_WAKE	0x1000
261 #define CONTEXT_DEAD	0x0800
262 #define CONTEXT_ACTIVE	0x0400
263 
264 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
265 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
266 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
267 
268 #define OHCI1394_REGISTER_SIZE		0x800
269 #define OHCI1394_PCI_HCI_Control	0x40
270 #define SELF_ID_BUF_SIZE		0x800
271 #define OHCI_TCODE_PHY_PACKET		0x0e
272 #define OHCI_VERSION_1_1		0x010010
273 
274 static char ohci_driver_name[] = KBUILD_MODNAME;
275 
276 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
277 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
278 #define PCI_DEVICE_ID_CREATIVE_SB1394	0x4001
279 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
280 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
281 #define PCI_DEVICE_ID_TI_TSB12LV26	0x8020
282 #define PCI_DEVICE_ID_TI_TSB82AA2	0x8025
283 #define PCI_DEVICE_ID_VIA_VT630X	0x3044
284 #define PCI_REV_ID_VIA_VT6306		0x46
285 #define PCI_DEVICE_ID_VIA_VT6315	0x3403
286 
287 #define QUIRK_CYCLE_TIMER		0x1
288 #define QUIRK_RESET_PACKET		0x2
289 #define QUIRK_BE_HEADERS		0x4
290 #define QUIRK_NO_1394A			0x8
291 #define QUIRK_NO_MSI			0x10
292 #define QUIRK_TI_SLLZ059		0x20
293 #define QUIRK_IR_WAKE			0x40
294 
295 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
296 static const struct {
297 	unsigned short vendor, device, revision, flags;
298 } ohci_quirks[] = {
299 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
300 		QUIRK_CYCLE_TIMER},
301 
302 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
303 		QUIRK_BE_HEADERS},
304 
305 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
306 		QUIRK_NO_MSI},
307 
308 	{PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
309 		QUIRK_RESET_PACKET},
310 
311 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
312 		QUIRK_NO_MSI},
313 
314 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
315 		QUIRK_CYCLE_TIMER},
316 
317 	{PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
318 		QUIRK_NO_MSI},
319 
320 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
321 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
322 
323 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
324 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
325 
326 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
327 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
328 
329 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
330 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
331 
332 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
333 		QUIRK_RESET_PACKET},
334 
335 	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT630X, PCI_REV_ID_VIA_VT6306,
336 		QUIRK_CYCLE_TIMER | QUIRK_IR_WAKE},
337 
338 	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, 0,
339 		QUIRK_CYCLE_TIMER /* FIXME: necessary? */ | QUIRK_NO_MSI},
340 
341 	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, PCI_ANY_ID,
342 		QUIRK_NO_MSI},
343 
344 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
345 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
346 };
347 
348 /* This overrides anything that was found in ohci_quirks[]. */
349 static int param_quirks;
350 module_param_named(quirks, param_quirks, int, 0644);
351 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
352 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
353 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
354 	", AR/selfID endianness = "	__stringify(QUIRK_BE_HEADERS)
355 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
356 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
357 	", TI SLLZ059 erratum = "	__stringify(QUIRK_TI_SLLZ059)
358 	", IR wake unreliable = "	__stringify(QUIRK_IR_WAKE)
359 	")");
360 
361 #define OHCI_PARAM_DEBUG_AT_AR		1
362 #define OHCI_PARAM_DEBUG_SELFIDS	2
363 #define OHCI_PARAM_DEBUG_IRQS		4
364 #define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */
365 
366 static int param_debug;
367 module_param_named(debug, param_debug, int, 0644);
368 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
369 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
370 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
371 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
372 	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
373 	", or a combination, or all = -1)");
374 
375 static bool param_remote_dma;
376 module_param_named(remote_dma, param_remote_dma, bool, 0444);
377 MODULE_PARM_DESC(remote_dma, "Enable unfiltered remote DMA (default = N)");
378 
379 static void log_irqs(struct fw_ohci *ohci, u32 evt)
380 {
381 	if (likely(!(param_debug &
382 			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
383 		return;
384 
385 	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
386 	    !(evt & OHCI1394_busReset))
387 		return;
388 
389 	ohci_notice(ohci, "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
390 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
391 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
392 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
393 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
394 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
395 	    evt & OHCI1394_isochRx		? " IR"			: "",
396 	    evt & OHCI1394_isochTx		? " IT"			: "",
397 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
398 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
399 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
400 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
401 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
402 	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
403 	    evt & OHCI1394_busReset		? " busReset"		: "",
404 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
405 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
406 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
407 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
408 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
409 		    OHCI1394_cycleInconsistent |
410 		    OHCI1394_regAccessFail | OHCI1394_busReset)
411 						? " ?"			: "");
412 }
413 
414 static const char *speed[] = {
415 	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
416 };
417 static const char *power[] = {
418 	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
419 	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
420 };
421 static const char port[] = { '.', '-', 'p', 'c', };
422 
423 static char _p(u32 *s, int shift)
424 {
425 	return port[*s >> shift & 3];
426 }
427 
428 static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
429 {
430 	u32 *s;
431 
432 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
433 		return;
434 
435 	ohci_notice(ohci, "%d selfIDs, generation %d, local node ID %04x\n",
436 		    self_id_count, generation, ohci->node_id);
437 
438 	for (s = ohci->self_id_buffer; self_id_count--; ++s)
439 		if ((*s & 1 << 23) == 0)
440 			ohci_notice(ohci,
441 			    "selfID 0: %08x, phy %d [%c%c%c] %s gc=%d %s %s%s%s\n",
442 			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
443 			    speed[*s >> 14 & 3], *s >> 16 & 63,
444 			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
445 			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
446 		else
447 			ohci_notice(ohci,
448 			    "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
449 			    *s, *s >> 24 & 63,
450 			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
451 			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
452 }
453 
454 static const char *evts[] = {
455 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
456 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
457 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
458 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
459 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
460 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
461 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
462 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
463 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
464 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
465 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
466 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
467 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
468 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
469 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
470 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
471 	[0x20] = "pending/cancelled",
472 };
473 static const char *tcodes[] = {
474 	[0x0] = "QW req",		[0x1] = "BW req",
475 	[0x2] = "W resp",		[0x3] = "-reserved-",
476 	[0x4] = "QR req",		[0x5] = "BR req",
477 	[0x6] = "QR resp",		[0x7] = "BR resp",
478 	[0x8] = "cycle start",		[0x9] = "Lk req",
479 	[0xa] = "async stream packet",	[0xb] = "Lk resp",
480 	[0xc] = "-reserved-",		[0xd] = "-reserved-",
481 	[0xe] = "link internal",	[0xf] = "-reserved-",
482 };
483 
484 static void log_ar_at_event(struct fw_ohci *ohci,
485 			    char dir, int speed, u32 *header, int evt)
486 {
487 	int tcode = header[0] >> 4 & 0xf;
488 	char specific[12];
489 
490 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
491 		return;
492 
493 	if (unlikely(evt >= ARRAY_SIZE(evts)))
494 			evt = 0x1f;
495 
496 	if (evt == OHCI1394_evt_bus_reset) {
497 		ohci_notice(ohci, "A%c evt_bus_reset, generation %d\n",
498 			    dir, (header[2] >> 16) & 0xff);
499 		return;
500 	}
501 
502 	switch (tcode) {
503 	case 0x0: case 0x6: case 0x8:
504 		snprintf(specific, sizeof(specific), " = %08x",
505 			 be32_to_cpu((__force __be32)header[3]));
506 		break;
507 	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
508 		snprintf(specific, sizeof(specific), " %x,%x",
509 			 header[3] >> 16, header[3] & 0xffff);
510 		break;
511 	default:
512 		specific[0] = '\0';
513 	}
514 
515 	switch (tcode) {
516 	case 0xa:
517 		ohci_notice(ohci, "A%c %s, %s\n",
518 			    dir, evts[evt], tcodes[tcode]);
519 		break;
520 	case 0xe:
521 		ohci_notice(ohci, "A%c %s, PHY %08x %08x\n",
522 			    dir, evts[evt], header[1], header[2]);
523 		break;
524 	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
525 		ohci_notice(ohci,
526 			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s, %04x%08x%s\n",
527 			    dir, speed, header[0] >> 10 & 0x3f,
528 			    header[1] >> 16, header[0] >> 16, evts[evt],
529 			    tcodes[tcode], header[1] & 0xffff, header[2], specific);
530 		break;
531 	default:
532 		ohci_notice(ohci,
533 			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s%s\n",
534 			    dir, speed, header[0] >> 10 & 0x3f,
535 			    header[1] >> 16, header[0] >> 16, evts[evt],
536 			    tcodes[tcode], specific);
537 	}
538 }
539 
540 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
541 {
542 	writel(data, ohci->registers + offset);
543 }
544 
545 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
546 {
547 	return readl(ohci->registers + offset);
548 }
549 
550 static inline void flush_writes(const struct fw_ohci *ohci)
551 {
552 	/* Do a dummy read to flush writes. */
553 	reg_read(ohci, OHCI1394_Version);
554 }
555 
556 /*
557  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
558  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
559  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
560  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
561  */
562 static int read_phy_reg(struct fw_ohci *ohci, int addr)
563 {
564 	u32 val;
565 	int i;
566 
567 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
568 	for (i = 0; i < 3 + 100; i++) {
569 		val = reg_read(ohci, OHCI1394_PhyControl);
570 		if (!~val)
571 			return -ENODEV; /* Card was ejected. */
572 
573 		if (val & OHCI1394_PhyControl_ReadDone)
574 			return OHCI1394_PhyControl_ReadData(val);
575 
576 		/*
577 		 * Try a few times without waiting.  Sleeping is necessary
578 		 * only when the link/PHY interface is busy.
579 		 */
580 		if (i >= 3)
581 			msleep(1);
582 	}
583 	ohci_err(ohci, "failed to read phy reg %d\n", addr);
584 	dump_stack();
585 
586 	return -EBUSY;
587 }
588 
589 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
590 {
591 	int i;
592 
593 	reg_write(ohci, OHCI1394_PhyControl,
594 		  OHCI1394_PhyControl_Write(addr, val));
595 	for (i = 0; i < 3 + 100; i++) {
596 		val = reg_read(ohci, OHCI1394_PhyControl);
597 		if (!~val)
598 			return -ENODEV; /* Card was ejected. */
599 
600 		if (!(val & OHCI1394_PhyControl_WritePending))
601 			return 0;
602 
603 		if (i >= 3)
604 			msleep(1);
605 	}
606 	ohci_err(ohci, "failed to write phy reg %d, val %u\n", addr, val);
607 	dump_stack();
608 
609 	return -EBUSY;
610 }
611 
612 static int update_phy_reg(struct fw_ohci *ohci, int addr,
613 			  int clear_bits, int set_bits)
614 {
615 	int ret = read_phy_reg(ohci, addr);
616 	if (ret < 0)
617 		return ret;
618 
619 	/*
620 	 * The interrupt status bits are cleared by writing a one bit.
621 	 * Avoid clearing them unless explicitly requested in set_bits.
622 	 */
623 	if (addr == 5)
624 		clear_bits |= PHY_INT_STATUS_BITS;
625 
626 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
627 }
628 
629 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
630 {
631 	int ret;
632 
633 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
634 	if (ret < 0)
635 		return ret;
636 
637 	return read_phy_reg(ohci, addr);
638 }
639 
640 static int ohci_read_phy_reg(struct fw_card *card, int addr)
641 {
642 	struct fw_ohci *ohci = fw_ohci(card);
643 	int ret;
644 
645 	mutex_lock(&ohci->phy_reg_mutex);
646 	ret = read_phy_reg(ohci, addr);
647 	mutex_unlock(&ohci->phy_reg_mutex);
648 
649 	return ret;
650 }
651 
652 static int ohci_update_phy_reg(struct fw_card *card, int addr,
653 			       int clear_bits, int set_bits)
654 {
655 	struct fw_ohci *ohci = fw_ohci(card);
656 	int ret;
657 
658 	mutex_lock(&ohci->phy_reg_mutex);
659 	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
660 	mutex_unlock(&ohci->phy_reg_mutex);
661 
662 	return ret;
663 }
664 
665 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
666 {
667 	return page_private(ctx->pages[i]);
668 }
669 
670 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
671 {
672 	struct descriptor *d;
673 
674 	d = &ctx->descriptors[index];
675 	d->branch_address  &= cpu_to_le32(~0xf);
676 	d->res_count       =  cpu_to_le16(PAGE_SIZE);
677 	d->transfer_status =  0;
678 
679 	wmb(); /* finish init of new descriptors before branch_address update */
680 	d = &ctx->descriptors[ctx->last_buffer_index];
681 	d->branch_address  |= cpu_to_le32(1);
682 
683 	ctx->last_buffer_index = index;
684 
685 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
686 }
687 
688 static void ar_context_release(struct ar_context *ctx)
689 {
690 	unsigned int i;
691 
692 	vunmap(ctx->buffer);
693 
694 	for (i = 0; i < AR_BUFFERS; i++)
695 		if (ctx->pages[i]) {
696 			dma_unmap_page(ctx->ohci->card.device,
697 				       ar_buffer_bus(ctx, i),
698 				       PAGE_SIZE, DMA_FROM_DEVICE);
699 			__free_page(ctx->pages[i]);
700 		}
701 }
702 
703 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
704 {
705 	struct fw_ohci *ohci = ctx->ohci;
706 
707 	if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
708 		reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
709 		flush_writes(ohci);
710 
711 		ohci_err(ohci, "AR error: %s; DMA stopped\n", error_msg);
712 	}
713 	/* FIXME: restart? */
714 }
715 
716 static inline unsigned int ar_next_buffer_index(unsigned int index)
717 {
718 	return (index + 1) % AR_BUFFERS;
719 }
720 
721 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
722 {
723 	return ar_next_buffer_index(ctx->last_buffer_index);
724 }
725 
726 /*
727  * We search for the buffer that contains the last AR packet DMA data written
728  * by the controller.
729  */
730 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
731 						 unsigned int *buffer_offset)
732 {
733 	unsigned int i, next_i, last = ctx->last_buffer_index;
734 	__le16 res_count, next_res_count;
735 
736 	i = ar_first_buffer_index(ctx);
737 	res_count = READ_ONCE(ctx->descriptors[i].res_count);
738 
739 	/* A buffer that is not yet completely filled must be the last one. */
740 	while (i != last && res_count == 0) {
741 
742 		/* Peek at the next descriptor. */
743 		next_i = ar_next_buffer_index(i);
744 		rmb(); /* read descriptors in order */
745 		next_res_count = READ_ONCE(ctx->descriptors[next_i].res_count);
746 		/*
747 		 * If the next descriptor is still empty, we must stop at this
748 		 * descriptor.
749 		 */
750 		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
751 			/*
752 			 * The exception is when the DMA data for one packet is
753 			 * split over three buffers; in this case, the middle
754 			 * buffer's descriptor might be never updated by the
755 			 * controller and look still empty, and we have to peek
756 			 * at the third one.
757 			 */
758 			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
759 				next_i = ar_next_buffer_index(next_i);
760 				rmb();
761 				next_res_count = READ_ONCE(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 = vmap(pages, ARRAY_SIZE(pages), VM_MAP, PAGE_KERNEL);
1014 	if (!ctx->buffer)
1015 		goto out_of_memory;
1016 
1017 	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
1018 	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
1019 
1020 	for (i = 0; i < AR_BUFFERS; i++) {
1021 		d = &ctx->descriptors[i];
1022 		d->req_count      = cpu_to_le16(PAGE_SIZE);
1023 		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
1024 						DESCRIPTOR_STATUS |
1025 						DESCRIPTOR_BRANCH_ALWAYS);
1026 		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
1027 		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
1028 			ar_next_buffer_index(i) * sizeof(struct descriptor));
1029 	}
1030 
1031 	return 0;
1032 
1033 out_of_memory:
1034 	ar_context_release(ctx);
1035 
1036 	return -ENOMEM;
1037 }
1038 
1039 static void ar_context_run(struct ar_context *ctx)
1040 {
1041 	unsigned int i;
1042 
1043 	for (i = 0; i < AR_BUFFERS; i++)
1044 		ar_context_link_page(ctx, i);
1045 
1046 	ctx->pointer = ctx->buffer;
1047 
1048 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1049 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1050 }
1051 
1052 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1053 {
1054 	__le16 branch;
1055 
1056 	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1057 
1058 	/* figure out which descriptor the branch address goes in */
1059 	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1060 		return d;
1061 	else
1062 		return d + z - 1;
1063 }
1064 
1065 static void context_tasklet(unsigned long data)
1066 {
1067 	struct context *ctx = (struct context *) data;
1068 	struct descriptor *d, *last;
1069 	u32 address;
1070 	int z;
1071 	struct descriptor_buffer *desc;
1072 
1073 	desc = list_entry(ctx->buffer_list.next,
1074 			struct descriptor_buffer, list);
1075 	last = ctx->last;
1076 	while (last->branch_address != 0) {
1077 		struct descriptor_buffer *old_desc = desc;
1078 		address = le32_to_cpu(last->branch_address);
1079 		z = address & 0xf;
1080 		address &= ~0xf;
1081 		ctx->current_bus = address;
1082 
1083 		/* If the branch address points to a buffer outside of the
1084 		 * current buffer, advance to the next buffer. */
1085 		if (address < desc->buffer_bus ||
1086 				address >= desc->buffer_bus + desc->used)
1087 			desc = list_entry(desc->list.next,
1088 					struct descriptor_buffer, list);
1089 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1090 		last = find_branch_descriptor(d, z);
1091 
1092 		if (!ctx->callback(ctx, d, last))
1093 			break;
1094 
1095 		if (old_desc != desc) {
1096 			/* If we've advanced to the next buffer, move the
1097 			 * previous buffer to the free list. */
1098 			unsigned long flags;
1099 			old_desc->used = 0;
1100 			spin_lock_irqsave(&ctx->ohci->lock, flags);
1101 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1102 			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1103 		}
1104 		ctx->last = last;
1105 	}
1106 }
1107 
1108 /*
1109  * Allocate a new buffer and add it to the list of free buffers for this
1110  * context.  Must be called with ohci->lock held.
1111  */
1112 static int context_add_buffer(struct context *ctx)
1113 {
1114 	struct descriptor_buffer *desc;
1115 	dma_addr_t uninitialized_var(bus_addr);
1116 	int offset;
1117 
1118 	/*
1119 	 * 16MB of descriptors should be far more than enough for any DMA
1120 	 * program.  This will catch run-away userspace or DoS attacks.
1121 	 */
1122 	if (ctx->total_allocation >= 16*1024*1024)
1123 		return -ENOMEM;
1124 
1125 	desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1126 			&bus_addr, GFP_ATOMIC);
1127 	if (!desc)
1128 		return -ENOMEM;
1129 
1130 	offset = (void *)&desc->buffer - (void *)desc;
1131 	desc->buffer_size = PAGE_SIZE - offset;
1132 	desc->buffer_bus = bus_addr + offset;
1133 	desc->used = 0;
1134 
1135 	list_add_tail(&desc->list, &ctx->buffer_list);
1136 	ctx->total_allocation += PAGE_SIZE;
1137 
1138 	return 0;
1139 }
1140 
1141 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1142 			u32 regs, descriptor_callback_t callback)
1143 {
1144 	ctx->ohci = ohci;
1145 	ctx->regs = regs;
1146 	ctx->total_allocation = 0;
1147 
1148 	INIT_LIST_HEAD(&ctx->buffer_list);
1149 	if (context_add_buffer(ctx) < 0)
1150 		return -ENOMEM;
1151 
1152 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1153 			struct descriptor_buffer, list);
1154 
1155 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1156 	ctx->callback = callback;
1157 
1158 	/*
1159 	 * We put a dummy descriptor in the buffer that has a NULL
1160 	 * branch address and looks like it's been sent.  That way we
1161 	 * have a descriptor to append DMA programs to.
1162 	 */
1163 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1164 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1165 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1166 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1167 	ctx->last = ctx->buffer_tail->buffer;
1168 	ctx->prev = ctx->buffer_tail->buffer;
1169 	ctx->prev_z = 1;
1170 
1171 	return 0;
1172 }
1173 
1174 static void context_release(struct context *ctx)
1175 {
1176 	struct fw_card *card = &ctx->ohci->card;
1177 	struct descriptor_buffer *desc, *tmp;
1178 
1179 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1180 		dma_free_coherent(card->device, PAGE_SIZE, desc,
1181 			desc->buffer_bus -
1182 			((void *)&desc->buffer - (void *)desc));
1183 }
1184 
1185 /* Must be called with ohci->lock held */
1186 static struct descriptor *context_get_descriptors(struct context *ctx,
1187 						  int z, dma_addr_t *d_bus)
1188 {
1189 	struct descriptor *d = NULL;
1190 	struct descriptor_buffer *desc = ctx->buffer_tail;
1191 
1192 	if (z * sizeof(*d) > desc->buffer_size)
1193 		return NULL;
1194 
1195 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1196 		/* No room for the descriptor in this buffer, so advance to the
1197 		 * next one. */
1198 
1199 		if (desc->list.next == &ctx->buffer_list) {
1200 			/* If there is no free buffer next in the list,
1201 			 * allocate one. */
1202 			if (context_add_buffer(ctx) < 0)
1203 				return NULL;
1204 		}
1205 		desc = list_entry(desc->list.next,
1206 				struct descriptor_buffer, list);
1207 		ctx->buffer_tail = desc;
1208 	}
1209 
1210 	d = desc->buffer + desc->used / sizeof(*d);
1211 	memset(d, 0, z * sizeof(*d));
1212 	*d_bus = desc->buffer_bus + desc->used;
1213 
1214 	return d;
1215 }
1216 
1217 static void context_run(struct context *ctx, u32 extra)
1218 {
1219 	struct fw_ohci *ohci = ctx->ohci;
1220 
1221 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1222 		  le32_to_cpu(ctx->last->branch_address));
1223 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1224 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1225 	ctx->running = true;
1226 	flush_writes(ohci);
1227 }
1228 
1229 static void context_append(struct context *ctx,
1230 			   struct descriptor *d, int z, int extra)
1231 {
1232 	dma_addr_t d_bus;
1233 	struct descriptor_buffer *desc = ctx->buffer_tail;
1234 	struct descriptor *d_branch;
1235 
1236 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1237 
1238 	desc->used += (z + extra) * sizeof(*d);
1239 
1240 	wmb(); /* finish init of new descriptors before branch_address update */
1241 
1242 	d_branch = find_branch_descriptor(ctx->prev, ctx->prev_z);
1243 	d_branch->branch_address = cpu_to_le32(d_bus | z);
1244 
1245 	/*
1246 	 * VT6306 incorrectly checks only the single descriptor at the
1247 	 * CommandPtr when the wake bit is written, so if it's a
1248 	 * multi-descriptor block starting with an INPUT_MORE, put a copy of
1249 	 * the branch address in the first descriptor.
1250 	 *
1251 	 * Not doing this for transmit contexts since not sure how it interacts
1252 	 * with skip addresses.
1253 	 */
1254 	if (unlikely(ctx->ohci->quirks & QUIRK_IR_WAKE) &&
1255 	    d_branch != ctx->prev &&
1256 	    (ctx->prev->control & cpu_to_le16(DESCRIPTOR_CMD)) ==
1257 	     cpu_to_le16(DESCRIPTOR_INPUT_MORE)) {
1258 		ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1259 	}
1260 
1261 	ctx->prev = d;
1262 	ctx->prev_z = z;
1263 }
1264 
1265 static void context_stop(struct context *ctx)
1266 {
1267 	struct fw_ohci *ohci = ctx->ohci;
1268 	u32 reg;
1269 	int i;
1270 
1271 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1272 	ctx->running = false;
1273 
1274 	for (i = 0; i < 1000; i++) {
1275 		reg = reg_read(ohci, CONTROL_SET(ctx->regs));
1276 		if ((reg & CONTEXT_ACTIVE) == 0)
1277 			return;
1278 
1279 		if (i)
1280 			udelay(10);
1281 	}
1282 	ohci_err(ohci, "DMA context still active (0x%08x)\n", reg);
1283 }
1284 
1285 struct driver_data {
1286 	u8 inline_data[8];
1287 	struct fw_packet *packet;
1288 };
1289 
1290 /*
1291  * This function apppends a packet to the DMA queue for transmission.
1292  * Must always be called with the ochi->lock held to ensure proper
1293  * generation handling and locking around packet queue manipulation.
1294  */
1295 static int at_context_queue_packet(struct context *ctx,
1296 				   struct fw_packet *packet)
1297 {
1298 	struct fw_ohci *ohci = ctx->ohci;
1299 	dma_addr_t d_bus, uninitialized_var(payload_bus);
1300 	struct driver_data *driver_data;
1301 	struct descriptor *d, *last;
1302 	__le32 *header;
1303 	int z, tcode;
1304 
1305 	d = context_get_descriptors(ctx, 4, &d_bus);
1306 	if (d == NULL) {
1307 		packet->ack = RCODE_SEND_ERROR;
1308 		return -1;
1309 	}
1310 
1311 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1312 	d[0].res_count = cpu_to_le16(packet->timestamp);
1313 
1314 	/*
1315 	 * The DMA format for asynchronous link packets is different
1316 	 * from the IEEE1394 layout, so shift the fields around
1317 	 * accordingly.
1318 	 */
1319 
1320 	tcode = (packet->header[0] >> 4) & 0x0f;
1321 	header = (__le32 *) &d[1];
1322 	switch (tcode) {
1323 	case TCODE_WRITE_QUADLET_REQUEST:
1324 	case TCODE_WRITE_BLOCK_REQUEST:
1325 	case TCODE_WRITE_RESPONSE:
1326 	case TCODE_READ_QUADLET_REQUEST:
1327 	case TCODE_READ_BLOCK_REQUEST:
1328 	case TCODE_READ_QUADLET_RESPONSE:
1329 	case TCODE_READ_BLOCK_RESPONSE:
1330 	case TCODE_LOCK_REQUEST:
1331 	case TCODE_LOCK_RESPONSE:
1332 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1333 					(packet->speed << 16));
1334 		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1335 					(packet->header[0] & 0xffff0000));
1336 		header[2] = cpu_to_le32(packet->header[2]);
1337 
1338 		if (TCODE_IS_BLOCK_PACKET(tcode))
1339 			header[3] = cpu_to_le32(packet->header[3]);
1340 		else
1341 			header[3] = (__force __le32) packet->header[3];
1342 
1343 		d[0].req_count = cpu_to_le16(packet->header_length);
1344 		break;
1345 
1346 	case TCODE_LINK_INTERNAL:
1347 		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1348 					(packet->speed << 16));
1349 		header[1] = cpu_to_le32(packet->header[1]);
1350 		header[2] = cpu_to_le32(packet->header[2]);
1351 		d[0].req_count = cpu_to_le16(12);
1352 
1353 		if (is_ping_packet(&packet->header[1]))
1354 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1355 		break;
1356 
1357 	case TCODE_STREAM_DATA:
1358 		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1359 					(packet->speed << 16));
1360 		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1361 		d[0].req_count = cpu_to_le16(8);
1362 		break;
1363 
1364 	default:
1365 		/* BUG(); */
1366 		packet->ack = RCODE_SEND_ERROR;
1367 		return -1;
1368 	}
1369 
1370 	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1371 	driver_data = (struct driver_data *) &d[3];
1372 	driver_data->packet = packet;
1373 	packet->driver_data = driver_data;
1374 
1375 	if (packet->payload_length > 0) {
1376 		if (packet->payload_length > sizeof(driver_data->inline_data)) {
1377 			payload_bus = dma_map_single(ohci->card.device,
1378 						     packet->payload,
1379 						     packet->payload_length,
1380 						     DMA_TO_DEVICE);
1381 			if (dma_mapping_error(ohci->card.device, payload_bus)) {
1382 				packet->ack = RCODE_SEND_ERROR;
1383 				return -1;
1384 			}
1385 			packet->payload_bus	= payload_bus;
1386 			packet->payload_mapped	= true;
1387 		} else {
1388 			memcpy(driver_data->inline_data, packet->payload,
1389 			       packet->payload_length);
1390 			payload_bus = d_bus + 3 * sizeof(*d);
1391 		}
1392 
1393 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1394 		d[2].data_address = cpu_to_le32(payload_bus);
1395 		last = &d[2];
1396 		z = 3;
1397 	} else {
1398 		last = &d[0];
1399 		z = 2;
1400 	}
1401 
1402 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1403 				     DESCRIPTOR_IRQ_ALWAYS |
1404 				     DESCRIPTOR_BRANCH_ALWAYS);
1405 
1406 	/* FIXME: Document how the locking works. */
1407 	if (ohci->generation != packet->generation) {
1408 		if (packet->payload_mapped)
1409 			dma_unmap_single(ohci->card.device, payload_bus,
1410 					 packet->payload_length, DMA_TO_DEVICE);
1411 		packet->ack = RCODE_GENERATION;
1412 		return -1;
1413 	}
1414 
1415 	context_append(ctx, d, z, 4 - z);
1416 
1417 	if (ctx->running)
1418 		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1419 	else
1420 		context_run(ctx, 0);
1421 
1422 	return 0;
1423 }
1424 
1425 static void at_context_flush(struct context *ctx)
1426 {
1427 	tasklet_disable(&ctx->tasklet);
1428 
1429 	ctx->flushing = true;
1430 	context_tasklet((unsigned long)ctx);
1431 	ctx->flushing = false;
1432 
1433 	tasklet_enable(&ctx->tasklet);
1434 }
1435 
1436 static int handle_at_packet(struct context *context,
1437 			    struct descriptor *d,
1438 			    struct descriptor *last)
1439 {
1440 	struct driver_data *driver_data;
1441 	struct fw_packet *packet;
1442 	struct fw_ohci *ohci = context->ohci;
1443 	int evt;
1444 
1445 	if (last->transfer_status == 0 && !context->flushing)
1446 		/* This descriptor isn't done yet, stop iteration. */
1447 		return 0;
1448 
1449 	driver_data = (struct driver_data *) &d[3];
1450 	packet = driver_data->packet;
1451 	if (packet == NULL)
1452 		/* This packet was cancelled, just continue. */
1453 		return 1;
1454 
1455 	if (packet->payload_mapped)
1456 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1457 				 packet->payload_length, DMA_TO_DEVICE);
1458 
1459 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1460 	packet->timestamp = le16_to_cpu(last->res_count);
1461 
1462 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);
1463 
1464 	switch (evt) {
1465 	case OHCI1394_evt_timeout:
1466 		/* Async response transmit timed out. */
1467 		packet->ack = RCODE_CANCELLED;
1468 		break;
1469 
1470 	case OHCI1394_evt_flushed:
1471 		/*
1472 		 * The packet was flushed should give same error as
1473 		 * when we try to use a stale generation count.
1474 		 */
1475 		packet->ack = RCODE_GENERATION;
1476 		break;
1477 
1478 	case OHCI1394_evt_missing_ack:
1479 		if (context->flushing)
1480 			packet->ack = RCODE_GENERATION;
1481 		else {
1482 			/*
1483 			 * Using a valid (current) generation count, but the
1484 			 * node is not on the bus or not sending acks.
1485 			 */
1486 			packet->ack = RCODE_NO_ACK;
1487 		}
1488 		break;
1489 
1490 	case ACK_COMPLETE + 0x10:
1491 	case ACK_PENDING + 0x10:
1492 	case ACK_BUSY_X + 0x10:
1493 	case ACK_BUSY_A + 0x10:
1494 	case ACK_BUSY_B + 0x10:
1495 	case ACK_DATA_ERROR + 0x10:
1496 	case ACK_TYPE_ERROR + 0x10:
1497 		packet->ack = evt - 0x10;
1498 		break;
1499 
1500 	case OHCI1394_evt_no_status:
1501 		if (context->flushing) {
1502 			packet->ack = RCODE_GENERATION;
1503 			break;
1504 		}
1505 		/* fall through */
1506 
1507 	default:
1508 		packet->ack = RCODE_SEND_ERROR;
1509 		break;
1510 	}
1511 
1512 	packet->callback(packet, &ohci->card, packet->ack);
1513 
1514 	return 1;
1515 }
1516 
1517 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
1518 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
1519 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
1520 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
1521 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
1522 
1523 static void handle_local_rom(struct fw_ohci *ohci,
1524 			     struct fw_packet *packet, u32 csr)
1525 {
1526 	struct fw_packet response;
1527 	int tcode, length, i;
1528 
1529 	tcode = HEADER_GET_TCODE(packet->header[0]);
1530 	if (TCODE_IS_BLOCK_PACKET(tcode))
1531 		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1532 	else
1533 		length = 4;
1534 
1535 	i = csr - CSR_CONFIG_ROM;
1536 	if (i + length > CONFIG_ROM_SIZE) {
1537 		fw_fill_response(&response, packet->header,
1538 				 RCODE_ADDRESS_ERROR, NULL, 0);
1539 	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
1540 		fw_fill_response(&response, packet->header,
1541 				 RCODE_TYPE_ERROR, NULL, 0);
1542 	} else {
1543 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1544 				 (void *) ohci->config_rom + i, length);
1545 	}
1546 
1547 	fw_core_handle_response(&ohci->card, &response);
1548 }
1549 
1550 static void handle_local_lock(struct fw_ohci *ohci,
1551 			      struct fw_packet *packet, u32 csr)
1552 {
1553 	struct fw_packet response;
1554 	int tcode, length, ext_tcode, sel, try;
1555 	__be32 *payload, lock_old;
1556 	u32 lock_arg, lock_data;
1557 
1558 	tcode = HEADER_GET_TCODE(packet->header[0]);
1559 	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1560 	payload = packet->payload;
1561 	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1562 
1563 	if (tcode == TCODE_LOCK_REQUEST &&
1564 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1565 		lock_arg = be32_to_cpu(payload[0]);
1566 		lock_data = be32_to_cpu(payload[1]);
1567 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1568 		lock_arg = 0;
1569 		lock_data = 0;
1570 	} else {
1571 		fw_fill_response(&response, packet->header,
1572 				 RCODE_TYPE_ERROR, NULL, 0);
1573 		goto out;
1574 	}
1575 
1576 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1577 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1578 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1579 	reg_write(ohci, OHCI1394_CSRControl, sel);
1580 
1581 	for (try = 0; try < 20; try++)
1582 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1583 			lock_old = cpu_to_be32(reg_read(ohci,
1584 							OHCI1394_CSRData));
1585 			fw_fill_response(&response, packet->header,
1586 					 RCODE_COMPLETE,
1587 					 &lock_old, sizeof(lock_old));
1588 			goto out;
1589 		}
1590 
1591 	ohci_err(ohci, "swap not done (CSR lock timeout)\n");
1592 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1593 
1594  out:
1595 	fw_core_handle_response(&ohci->card, &response);
1596 }
1597 
1598 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1599 {
1600 	u64 offset, csr;
1601 
1602 	if (ctx == &ctx->ohci->at_request_ctx) {
1603 		packet->ack = ACK_PENDING;
1604 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1605 	}
1606 
1607 	offset =
1608 		((unsigned long long)
1609 		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1610 		packet->header[2];
1611 	csr = offset - CSR_REGISTER_BASE;
1612 
1613 	/* Handle config rom reads. */
1614 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1615 		handle_local_rom(ctx->ohci, packet, csr);
1616 	else switch (csr) {
1617 	case CSR_BUS_MANAGER_ID:
1618 	case CSR_BANDWIDTH_AVAILABLE:
1619 	case CSR_CHANNELS_AVAILABLE_HI:
1620 	case CSR_CHANNELS_AVAILABLE_LO:
1621 		handle_local_lock(ctx->ohci, packet, csr);
1622 		break;
1623 	default:
1624 		if (ctx == &ctx->ohci->at_request_ctx)
1625 			fw_core_handle_request(&ctx->ohci->card, packet);
1626 		else
1627 			fw_core_handle_response(&ctx->ohci->card, packet);
1628 		break;
1629 	}
1630 
1631 	if (ctx == &ctx->ohci->at_response_ctx) {
1632 		packet->ack = ACK_COMPLETE;
1633 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1634 	}
1635 }
1636 
1637 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1638 {
1639 	unsigned long flags;
1640 	int ret;
1641 
1642 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1643 
1644 	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1645 	    ctx->ohci->generation == packet->generation) {
1646 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1647 		handle_local_request(ctx, packet);
1648 		return;
1649 	}
1650 
1651 	ret = at_context_queue_packet(ctx, packet);
1652 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1653 
1654 	if (ret < 0)
1655 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1656 
1657 }
1658 
1659 static void detect_dead_context(struct fw_ohci *ohci,
1660 				const char *name, unsigned int regs)
1661 {
1662 	u32 ctl;
1663 
1664 	ctl = reg_read(ohci, CONTROL_SET(regs));
1665 	if (ctl & CONTEXT_DEAD)
1666 		ohci_err(ohci, "DMA context %s has stopped, error code: %s\n",
1667 			name, evts[ctl & 0x1f]);
1668 }
1669 
1670 static void handle_dead_contexts(struct fw_ohci *ohci)
1671 {
1672 	unsigned int i;
1673 	char name[8];
1674 
1675 	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1676 	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1677 	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1678 	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1679 	for (i = 0; i < 32; ++i) {
1680 		if (!(ohci->it_context_support & (1 << i)))
1681 			continue;
1682 		sprintf(name, "IT%u", i);
1683 		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1684 	}
1685 	for (i = 0; i < 32; ++i) {
1686 		if (!(ohci->ir_context_support & (1 << i)))
1687 			continue;
1688 		sprintf(name, "IR%u", i);
1689 		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1690 	}
1691 	/* TODO: maybe try to flush and restart the dead contexts */
1692 }
1693 
1694 static u32 cycle_timer_ticks(u32 cycle_timer)
1695 {
1696 	u32 ticks;
1697 
1698 	ticks = cycle_timer & 0xfff;
1699 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1700 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1701 
1702 	return ticks;
1703 }
1704 
1705 /*
1706  * Some controllers exhibit one or more of the following bugs when updating the
1707  * iso cycle timer register:
1708  *  - When the lowest six bits are wrapping around to zero, a read that happens
1709  *    at the same time will return garbage in the lowest ten bits.
1710  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1711  *    not incremented for about 60 ns.
1712  *  - Occasionally, the entire register reads zero.
1713  *
1714  * To catch these, we read the register three times and ensure that the
1715  * difference between each two consecutive reads is approximately the same, i.e.
1716  * less than twice the other.  Furthermore, any negative difference indicates an
1717  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1718  * execute, so we have enough precision to compute the ratio of the differences.)
1719  */
1720 static u32 get_cycle_time(struct fw_ohci *ohci)
1721 {
1722 	u32 c0, c1, c2;
1723 	u32 t0, t1, t2;
1724 	s32 diff01, diff12;
1725 	int i;
1726 
1727 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1728 
1729 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1730 		i = 0;
1731 		c1 = c2;
1732 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1733 		do {
1734 			c0 = c1;
1735 			c1 = c2;
1736 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1737 			t0 = cycle_timer_ticks(c0);
1738 			t1 = cycle_timer_ticks(c1);
1739 			t2 = cycle_timer_ticks(c2);
1740 			diff01 = t1 - t0;
1741 			diff12 = t2 - t1;
1742 		} while ((diff01 <= 0 || diff12 <= 0 ||
1743 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1744 			 && i++ < 20);
1745 	}
1746 
1747 	return c2;
1748 }
1749 
1750 /*
1751  * This function has to be called at least every 64 seconds.  The bus_time
1752  * field stores not only the upper 25 bits of the BUS_TIME register but also
1753  * the most significant bit of the cycle timer in bit 6 so that we can detect
1754  * changes in this bit.
1755  */
1756 static u32 update_bus_time(struct fw_ohci *ohci)
1757 {
1758 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1759 
1760 	if (unlikely(!ohci->bus_time_running)) {
1761 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_cycle64Seconds);
1762 		ohci->bus_time = (lower_32_bits(get_seconds()) & ~0x7f) |
1763 		                 (cycle_time_seconds & 0x40);
1764 		ohci->bus_time_running = true;
1765 	}
1766 
1767 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1768 		ohci->bus_time += 0x40;
1769 
1770 	return ohci->bus_time | cycle_time_seconds;
1771 }
1772 
1773 static int get_status_for_port(struct fw_ohci *ohci, int port_index)
1774 {
1775 	int reg;
1776 
1777 	mutex_lock(&ohci->phy_reg_mutex);
1778 	reg = write_phy_reg(ohci, 7, port_index);
1779 	if (reg >= 0)
1780 		reg = read_phy_reg(ohci, 8);
1781 	mutex_unlock(&ohci->phy_reg_mutex);
1782 	if (reg < 0)
1783 		return reg;
1784 
1785 	switch (reg & 0x0f) {
1786 	case 0x06:
1787 		return 2;	/* is child node (connected to parent node) */
1788 	case 0x0e:
1789 		return 3;	/* is parent node (connected to child node) */
1790 	}
1791 	return 1;		/* not connected */
1792 }
1793 
1794 static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
1795 	int self_id_count)
1796 {
1797 	int i;
1798 	u32 entry;
1799 
1800 	for (i = 0; i < self_id_count; i++) {
1801 		entry = ohci->self_id_buffer[i];
1802 		if ((self_id & 0xff000000) == (entry & 0xff000000))
1803 			return -1;
1804 		if ((self_id & 0xff000000) < (entry & 0xff000000))
1805 			return i;
1806 	}
1807 	return i;
1808 }
1809 
1810 static int initiated_reset(struct fw_ohci *ohci)
1811 {
1812 	int reg;
1813 	int ret = 0;
1814 
1815 	mutex_lock(&ohci->phy_reg_mutex);
1816 	reg = write_phy_reg(ohci, 7, 0xe0); /* Select page 7 */
1817 	if (reg >= 0) {
1818 		reg = read_phy_reg(ohci, 8);
1819 		reg |= 0x40;
1820 		reg = write_phy_reg(ohci, 8, reg); /* set PMODE bit */
1821 		if (reg >= 0) {
1822 			reg = read_phy_reg(ohci, 12); /* read register 12 */
1823 			if (reg >= 0) {
1824 				if ((reg & 0x08) == 0x08) {
1825 					/* bit 3 indicates "initiated reset" */
1826 					ret = 0x2;
1827 				}
1828 			}
1829 		}
1830 	}
1831 	mutex_unlock(&ohci->phy_reg_mutex);
1832 	return ret;
1833 }
1834 
1835 /*
1836  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1837  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1838  * Construct the selfID from phy register contents.
1839  */
1840 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
1841 {
1842 	int reg, i, pos, status;
1843 	/* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
1844 	u32 self_id = 0x8040c800;
1845 
1846 	reg = reg_read(ohci, OHCI1394_NodeID);
1847 	if (!(reg & OHCI1394_NodeID_idValid)) {
1848 		ohci_notice(ohci,
1849 			    "node ID not valid, new bus reset in progress\n");
1850 		return -EBUSY;
1851 	}
1852 	self_id |= ((reg & 0x3f) << 24); /* phy ID */
1853 
1854 	reg = ohci_read_phy_reg(&ohci->card, 4);
1855 	if (reg < 0)
1856 		return reg;
1857 	self_id |= ((reg & 0x07) << 8); /* power class */
1858 
1859 	reg = ohci_read_phy_reg(&ohci->card, 1);
1860 	if (reg < 0)
1861 		return reg;
1862 	self_id |= ((reg & 0x3f) << 16); /* gap count */
1863 
1864 	for (i = 0; i < 3; i++) {
1865 		status = get_status_for_port(ohci, i);
1866 		if (status < 0)
1867 			return status;
1868 		self_id |= ((status & 0x3) << (6 - (i * 2)));
1869 	}
1870 
1871 	self_id |= initiated_reset(ohci);
1872 
1873 	pos = get_self_id_pos(ohci, self_id, self_id_count);
1874 	if (pos >= 0) {
1875 		memmove(&(ohci->self_id_buffer[pos+1]),
1876 			&(ohci->self_id_buffer[pos]),
1877 			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
1878 		ohci->self_id_buffer[pos] = self_id;
1879 		self_id_count++;
1880 	}
1881 	return self_id_count;
1882 }
1883 
1884 static void bus_reset_work(struct work_struct *work)
1885 {
1886 	struct fw_ohci *ohci =
1887 		container_of(work, struct fw_ohci, bus_reset_work);
1888 	int self_id_count, generation, new_generation, i, j;
1889 	u32 reg;
1890 	void *free_rom = NULL;
1891 	dma_addr_t free_rom_bus = 0;
1892 	bool is_new_root;
1893 
1894 	reg = reg_read(ohci, OHCI1394_NodeID);
1895 	if (!(reg & OHCI1394_NodeID_idValid)) {
1896 		ohci_notice(ohci,
1897 			    "node ID not valid, new bus reset in progress\n");
1898 		return;
1899 	}
1900 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1901 		ohci_notice(ohci, "malconfigured bus\n");
1902 		return;
1903 	}
1904 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1905 			       OHCI1394_NodeID_nodeNumber);
1906 
1907 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1908 	if (!(ohci->is_root && is_new_root))
1909 		reg_write(ohci, OHCI1394_LinkControlSet,
1910 			  OHCI1394_LinkControl_cycleMaster);
1911 	ohci->is_root = is_new_root;
1912 
1913 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
1914 	if (reg & OHCI1394_SelfIDCount_selfIDError) {
1915 		ohci_notice(ohci, "self ID receive error\n");
1916 		return;
1917 	}
1918 	/*
1919 	 * The count in the SelfIDCount register is the number of
1920 	 * bytes in the self ID receive buffer.  Since we also receive
1921 	 * the inverted quadlets and a header quadlet, we shift one
1922 	 * bit extra to get the actual number of self IDs.
1923 	 */
1924 	self_id_count = (reg >> 3) & 0xff;
1925 
1926 	if (self_id_count > 252) {
1927 		ohci_notice(ohci, "bad selfIDSize (%08x)\n", reg);
1928 		return;
1929 	}
1930 
1931 	generation = (cond_le32_to_cpu(ohci->self_id[0]) >> 16) & 0xff;
1932 	rmb();
1933 
1934 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1935 		u32 id  = cond_le32_to_cpu(ohci->self_id[i]);
1936 		u32 id2 = cond_le32_to_cpu(ohci->self_id[i + 1]);
1937 
1938 		if (id != ~id2) {
1939 			/*
1940 			 * If the invalid data looks like a cycle start packet,
1941 			 * it's likely to be the result of the cycle master
1942 			 * having a wrong gap count.  In this case, the self IDs
1943 			 * so far are valid and should be processed so that the
1944 			 * bus manager can then correct the gap count.
1945 			 */
1946 			if (id == 0xffff008f) {
1947 				ohci_notice(ohci, "ignoring spurious self IDs\n");
1948 				self_id_count = j;
1949 				break;
1950 			}
1951 
1952 			ohci_notice(ohci, "bad self ID %d/%d (%08x != ~%08x)\n",
1953 				    j, self_id_count, id, id2);
1954 			return;
1955 		}
1956 		ohci->self_id_buffer[j] = id;
1957 	}
1958 
1959 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
1960 		self_id_count = find_and_insert_self_id(ohci, self_id_count);
1961 		if (self_id_count < 0) {
1962 			ohci_notice(ohci,
1963 				    "could not construct local self ID\n");
1964 			return;
1965 		}
1966 	}
1967 
1968 	if (self_id_count == 0) {
1969 		ohci_notice(ohci, "no self IDs\n");
1970 		return;
1971 	}
1972 	rmb();
1973 
1974 	/*
1975 	 * Check the consistency of the self IDs we just read.  The
1976 	 * problem we face is that a new bus reset can start while we
1977 	 * read out the self IDs from the DMA buffer. If this happens,
1978 	 * the DMA buffer will be overwritten with new self IDs and we
1979 	 * will read out inconsistent data.  The OHCI specification
1980 	 * (section 11.2) recommends a technique similar to
1981 	 * linux/seqlock.h, where we remember the generation of the
1982 	 * self IDs in the buffer before reading them out and compare
1983 	 * it to the current generation after reading them out.  If
1984 	 * the two generations match we know we have a consistent set
1985 	 * of self IDs.
1986 	 */
1987 
1988 	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1989 	if (new_generation != generation) {
1990 		ohci_notice(ohci, "new bus reset, discarding self ids\n");
1991 		return;
1992 	}
1993 
1994 	/* FIXME: Document how the locking works. */
1995 	spin_lock_irq(&ohci->lock);
1996 
1997 	ohci->generation = -1; /* prevent AT packet queueing */
1998 	context_stop(&ohci->at_request_ctx);
1999 	context_stop(&ohci->at_response_ctx);
2000 
2001 	spin_unlock_irq(&ohci->lock);
2002 
2003 	/*
2004 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
2005 	 * packets in the AT queues and software needs to drain them.
2006 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
2007 	 */
2008 	at_context_flush(&ohci->at_request_ctx);
2009 	at_context_flush(&ohci->at_response_ctx);
2010 
2011 	spin_lock_irq(&ohci->lock);
2012 
2013 	ohci->generation = generation;
2014 	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
2015 
2016 	if (ohci->quirks & QUIRK_RESET_PACKET)
2017 		ohci->request_generation = generation;
2018 
2019 	/*
2020 	 * This next bit is unrelated to the AT context stuff but we
2021 	 * have to do it under the spinlock also.  If a new config rom
2022 	 * was set up before this reset, the old one is now no longer
2023 	 * in use and we can free it. Update the config rom pointers
2024 	 * to point to the current config rom and clear the
2025 	 * next_config_rom pointer so a new update can take place.
2026 	 */
2027 
2028 	if (ohci->next_config_rom != NULL) {
2029 		if (ohci->next_config_rom != ohci->config_rom) {
2030 			free_rom      = ohci->config_rom;
2031 			free_rom_bus  = ohci->config_rom_bus;
2032 		}
2033 		ohci->config_rom      = ohci->next_config_rom;
2034 		ohci->config_rom_bus  = ohci->next_config_rom_bus;
2035 		ohci->next_config_rom = NULL;
2036 
2037 		/*
2038 		 * Restore config_rom image and manually update
2039 		 * config_rom registers.  Writing the header quadlet
2040 		 * will indicate that the config rom is ready, so we
2041 		 * do that last.
2042 		 */
2043 		reg_write(ohci, OHCI1394_BusOptions,
2044 			  be32_to_cpu(ohci->config_rom[2]));
2045 		ohci->config_rom[0] = ohci->next_header;
2046 		reg_write(ohci, OHCI1394_ConfigROMhdr,
2047 			  be32_to_cpu(ohci->next_header));
2048 	}
2049 
2050 	if (param_remote_dma) {
2051 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
2052 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
2053 	}
2054 
2055 	spin_unlock_irq(&ohci->lock);
2056 
2057 	if (free_rom)
2058 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2059 				  free_rom, free_rom_bus);
2060 
2061 	log_selfids(ohci, generation, self_id_count);
2062 
2063 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2064 				 self_id_count, ohci->self_id_buffer,
2065 				 ohci->csr_state_setclear_abdicate);
2066 	ohci->csr_state_setclear_abdicate = false;
2067 }
2068 
2069 static irqreturn_t irq_handler(int irq, void *data)
2070 {
2071 	struct fw_ohci *ohci = data;
2072 	u32 event, iso_event;
2073 	int i;
2074 
2075 	event = reg_read(ohci, OHCI1394_IntEventClear);
2076 
2077 	if (!event || !~event)
2078 		return IRQ_NONE;
2079 
2080 	/*
2081 	 * busReset and postedWriteErr must not be cleared yet
2082 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2083 	 */
2084 	reg_write(ohci, OHCI1394_IntEventClear,
2085 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2086 	log_irqs(ohci, event);
2087 
2088 	if (event & OHCI1394_selfIDComplete)
2089 		queue_work(selfid_workqueue, &ohci->bus_reset_work);
2090 
2091 	if (event & OHCI1394_RQPkt)
2092 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2093 
2094 	if (event & OHCI1394_RSPkt)
2095 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2096 
2097 	if (event & OHCI1394_reqTxComplete)
2098 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
2099 
2100 	if (event & OHCI1394_respTxComplete)
2101 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
2102 
2103 	if (event & OHCI1394_isochRx) {
2104 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2105 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2106 
2107 		while (iso_event) {
2108 			i = ffs(iso_event) - 1;
2109 			tasklet_schedule(
2110 				&ohci->ir_context_list[i].context.tasklet);
2111 			iso_event &= ~(1 << i);
2112 		}
2113 	}
2114 
2115 	if (event & OHCI1394_isochTx) {
2116 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2117 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2118 
2119 		while (iso_event) {
2120 			i = ffs(iso_event) - 1;
2121 			tasklet_schedule(
2122 				&ohci->it_context_list[i].context.tasklet);
2123 			iso_event &= ~(1 << i);
2124 		}
2125 	}
2126 
2127 	if (unlikely(event & OHCI1394_regAccessFail))
2128 		ohci_err(ohci, "register access failure\n");
2129 
2130 	if (unlikely(event & OHCI1394_postedWriteErr)) {
2131 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2132 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2133 		reg_write(ohci, OHCI1394_IntEventClear,
2134 			  OHCI1394_postedWriteErr);
2135 		if (printk_ratelimit())
2136 			ohci_err(ohci, "PCI posted write error\n");
2137 	}
2138 
2139 	if (unlikely(event & OHCI1394_cycleTooLong)) {
2140 		if (printk_ratelimit())
2141 			ohci_notice(ohci, "isochronous cycle too long\n");
2142 		reg_write(ohci, OHCI1394_LinkControlSet,
2143 			  OHCI1394_LinkControl_cycleMaster);
2144 	}
2145 
2146 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
2147 		/*
2148 		 * We need to clear this event bit in order to make
2149 		 * cycleMatch isochronous I/O work.  In theory we should
2150 		 * stop active cycleMatch iso contexts now and restart
2151 		 * them at least two cycles later.  (FIXME?)
2152 		 */
2153 		if (printk_ratelimit())
2154 			ohci_notice(ohci, "isochronous cycle inconsistent\n");
2155 	}
2156 
2157 	if (unlikely(event & OHCI1394_unrecoverableError))
2158 		handle_dead_contexts(ohci);
2159 
2160 	if (event & OHCI1394_cycle64Seconds) {
2161 		spin_lock(&ohci->lock);
2162 		update_bus_time(ohci);
2163 		spin_unlock(&ohci->lock);
2164 	} else
2165 		flush_writes(ohci);
2166 
2167 	return IRQ_HANDLED;
2168 }
2169 
2170 static int software_reset(struct fw_ohci *ohci)
2171 {
2172 	u32 val;
2173 	int i;
2174 
2175 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2176 	for (i = 0; i < 500; i++) {
2177 		val = reg_read(ohci, OHCI1394_HCControlSet);
2178 		if (!~val)
2179 			return -ENODEV; /* Card was ejected. */
2180 
2181 		if (!(val & OHCI1394_HCControl_softReset))
2182 			return 0;
2183 
2184 		msleep(1);
2185 	}
2186 
2187 	return -EBUSY;
2188 }
2189 
2190 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2191 {
2192 	size_t size = length * 4;
2193 
2194 	memcpy(dest, src, size);
2195 	if (size < CONFIG_ROM_SIZE)
2196 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2197 }
2198 
2199 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2200 {
2201 	bool enable_1394a;
2202 	int ret, clear, set, offset;
2203 
2204 	/* Check if the driver should configure link and PHY. */
2205 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2206 	      OHCI1394_HCControl_programPhyEnable))
2207 		return 0;
2208 
2209 	/* Paranoia: check whether the PHY supports 1394a, too. */
2210 	enable_1394a = false;
2211 	ret = read_phy_reg(ohci, 2);
2212 	if (ret < 0)
2213 		return ret;
2214 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2215 		ret = read_paged_phy_reg(ohci, 1, 8);
2216 		if (ret < 0)
2217 			return ret;
2218 		if (ret >= 1)
2219 			enable_1394a = true;
2220 	}
2221 
2222 	if (ohci->quirks & QUIRK_NO_1394A)
2223 		enable_1394a = false;
2224 
2225 	/* Configure PHY and link consistently. */
2226 	if (enable_1394a) {
2227 		clear = 0;
2228 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2229 	} else {
2230 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2231 		set = 0;
2232 	}
2233 	ret = update_phy_reg(ohci, 5, clear, set);
2234 	if (ret < 0)
2235 		return ret;
2236 
2237 	if (enable_1394a)
2238 		offset = OHCI1394_HCControlSet;
2239 	else
2240 		offset = OHCI1394_HCControlClear;
2241 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2242 
2243 	/* Clean up: configuration has been taken care of. */
2244 	reg_write(ohci, OHCI1394_HCControlClear,
2245 		  OHCI1394_HCControl_programPhyEnable);
2246 
2247 	return 0;
2248 }
2249 
2250 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2251 {
2252 	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2253 	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2254 	int reg, i;
2255 
2256 	reg = read_phy_reg(ohci, 2);
2257 	if (reg < 0)
2258 		return reg;
2259 	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2260 		return 0;
2261 
2262 	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2263 		reg = read_paged_phy_reg(ohci, 1, i + 10);
2264 		if (reg < 0)
2265 			return reg;
2266 		if (reg != id[i])
2267 			return 0;
2268 	}
2269 	return 1;
2270 }
2271 
2272 static int ohci_enable(struct fw_card *card,
2273 		       const __be32 *config_rom, size_t length)
2274 {
2275 	struct fw_ohci *ohci = fw_ohci(card);
2276 	u32 lps, version, irqs;
2277 	int i, ret;
2278 
2279 	ret = software_reset(ohci);
2280 	if (ret < 0) {
2281 		ohci_err(ohci, "failed to reset ohci card\n");
2282 		return ret;
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 
2298 	reg_write(ohci, OHCI1394_HCControlSet,
2299 		  OHCI1394_HCControl_LPS |
2300 		  OHCI1394_HCControl_postedWriteEnable);
2301 	flush_writes(ohci);
2302 
2303 	for (lps = 0, i = 0; !lps && i < 3; i++) {
2304 		msleep(50);
2305 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2306 		      OHCI1394_HCControl_LPS;
2307 	}
2308 
2309 	if (!lps) {
2310 		ohci_err(ohci, "failed to set Link Power Status\n");
2311 		return -EIO;
2312 	}
2313 
2314 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2315 		ret = probe_tsb41ba3d(ohci);
2316 		if (ret < 0)
2317 			return ret;
2318 		if (ret)
2319 			ohci_notice(ohci, "local TSB41BA3D phy\n");
2320 		else
2321 			ohci->quirks &= ~QUIRK_TI_SLLZ059;
2322 	}
2323 
2324 	reg_write(ohci, OHCI1394_HCControlClear,
2325 		  OHCI1394_HCControl_noByteSwapData);
2326 
2327 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2328 	reg_write(ohci, OHCI1394_LinkControlSet,
2329 		  OHCI1394_LinkControl_cycleTimerEnable |
2330 		  OHCI1394_LinkControl_cycleMaster);
2331 
2332 	reg_write(ohci, OHCI1394_ATRetries,
2333 		  OHCI1394_MAX_AT_REQ_RETRIES |
2334 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2335 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2336 		  (200 << 16));
2337 
2338 	ohci->bus_time_running = false;
2339 
2340 	for (i = 0; i < 32; i++)
2341 		if (ohci->ir_context_support & (1 << i))
2342 			reg_write(ohci, OHCI1394_IsoRcvContextControlClear(i),
2343 				  IR_CONTEXT_MULTI_CHANNEL_MODE);
2344 
2345 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2346 	if (version >= OHCI_VERSION_1_1) {
2347 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2348 			  0xfffffffe);
2349 		card->broadcast_channel_auto_allocated = true;
2350 	}
2351 
2352 	/* Get implemented bits of the priority arbitration request counter. */
2353 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2354 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2355 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2356 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2357 
2358 	reg_write(ohci, OHCI1394_PhyUpperBound, FW_MAX_PHYSICAL_RANGE >> 16);
2359 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2360 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2361 
2362 	ret = configure_1394a_enhancements(ohci);
2363 	if (ret < 0)
2364 		return ret;
2365 
2366 	/* Activate link_on bit and contender bit in our self ID packets.*/
2367 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2368 	if (ret < 0)
2369 		return ret;
2370 
2371 	/*
2372 	 * When the link is not yet enabled, the atomic config rom
2373 	 * update mechanism described below in ohci_set_config_rom()
2374 	 * is not active.  We have to update ConfigRomHeader and
2375 	 * BusOptions manually, and the write to ConfigROMmap takes
2376 	 * effect immediately.  We tie this to the enabling of the
2377 	 * link, so we have a valid config rom before enabling - the
2378 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2379 	 * values before enabling.
2380 	 *
2381 	 * However, when the ConfigROMmap is written, some controllers
2382 	 * always read back quadlets 0 and 2 from the config rom to
2383 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2384 	 * They shouldn't do that in this initial case where the link
2385 	 * isn't enabled.  This means we have to use the same
2386 	 * workaround here, setting the bus header to 0 and then write
2387 	 * the right values in the bus reset tasklet.
2388 	 */
2389 
2390 	if (config_rom) {
2391 		ohci->next_config_rom =
2392 			dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2393 					   &ohci->next_config_rom_bus,
2394 					   GFP_KERNEL);
2395 		if (ohci->next_config_rom == NULL)
2396 			return -ENOMEM;
2397 
2398 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2399 	} else {
2400 		/*
2401 		 * In the suspend case, config_rom is NULL, which
2402 		 * means that we just reuse the old config rom.
2403 		 */
2404 		ohci->next_config_rom = ohci->config_rom;
2405 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2406 	}
2407 
2408 	ohci->next_header = ohci->next_config_rom[0];
2409 	ohci->next_config_rom[0] = 0;
2410 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2411 	reg_write(ohci, OHCI1394_BusOptions,
2412 		  be32_to_cpu(ohci->next_config_rom[2]));
2413 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2414 
2415 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2416 
2417 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2418 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2419 		OHCI1394_isochTx | OHCI1394_isochRx |
2420 		OHCI1394_postedWriteErr |
2421 		OHCI1394_selfIDComplete |
2422 		OHCI1394_regAccessFail |
2423 		OHCI1394_cycleInconsistent |
2424 		OHCI1394_unrecoverableError |
2425 		OHCI1394_cycleTooLong |
2426 		OHCI1394_masterIntEnable;
2427 	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2428 		irqs |= OHCI1394_busReset;
2429 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2430 
2431 	reg_write(ohci, OHCI1394_HCControlSet,
2432 		  OHCI1394_HCControl_linkEnable |
2433 		  OHCI1394_HCControl_BIBimageValid);
2434 
2435 	reg_write(ohci, OHCI1394_LinkControlSet,
2436 		  OHCI1394_LinkControl_rcvSelfID |
2437 		  OHCI1394_LinkControl_rcvPhyPkt);
2438 
2439 	ar_context_run(&ohci->ar_request_ctx);
2440 	ar_context_run(&ohci->ar_response_ctx);
2441 
2442 	flush_writes(ohci);
2443 
2444 	/* We are ready to go, reset bus to finish initialization. */
2445 	fw_schedule_bus_reset(&ohci->card, false, true);
2446 
2447 	return 0;
2448 }
2449 
2450 static int ohci_set_config_rom(struct fw_card *card,
2451 			       const __be32 *config_rom, size_t length)
2452 {
2453 	struct fw_ohci *ohci;
2454 	__be32 *next_config_rom;
2455 	dma_addr_t uninitialized_var(next_config_rom_bus);
2456 
2457 	ohci = fw_ohci(card);
2458 
2459 	/*
2460 	 * When the OHCI controller is enabled, the config rom update
2461 	 * mechanism is a bit tricky, but easy enough to use.  See
2462 	 * section 5.5.6 in the OHCI specification.
2463 	 *
2464 	 * The OHCI controller caches the new config rom address in a
2465 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2466 	 * for the changes to take place.  When the bus reset is
2467 	 * detected, the controller loads the new values for the
2468 	 * ConfigRomHeader and BusOptions registers from the specified
2469 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2470 	 * shadow register. All automatically and atomically.
2471 	 *
2472 	 * Now, there's a twist to this story.  The automatic load of
2473 	 * ConfigRomHeader and BusOptions doesn't honor the
2474 	 * noByteSwapData bit, so with a be32 config rom, the
2475 	 * controller will load be32 values in to these registers
2476 	 * during the atomic update, even on litte endian
2477 	 * architectures.  The workaround we use is to put a 0 in the
2478 	 * header quadlet; 0 is endian agnostic and means that the
2479 	 * config rom isn't ready yet.  In the bus reset tasklet we
2480 	 * then set up the real values for the two registers.
2481 	 *
2482 	 * We use ohci->lock to avoid racing with the code that sets
2483 	 * ohci->next_config_rom to NULL (see bus_reset_work).
2484 	 */
2485 
2486 	next_config_rom =
2487 		dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2488 				   &next_config_rom_bus, GFP_KERNEL);
2489 	if (next_config_rom == NULL)
2490 		return -ENOMEM;
2491 
2492 	spin_lock_irq(&ohci->lock);
2493 
2494 	/*
2495 	 * If there is not an already pending config_rom update,
2496 	 * push our new allocation into the ohci->next_config_rom
2497 	 * and then mark the local variable as null so that we
2498 	 * won't deallocate the new buffer.
2499 	 *
2500 	 * OTOH, if there is a pending config_rom update, just
2501 	 * use that buffer with the new config_rom data, and
2502 	 * let this routine free the unused DMA allocation.
2503 	 */
2504 
2505 	if (ohci->next_config_rom == NULL) {
2506 		ohci->next_config_rom = next_config_rom;
2507 		ohci->next_config_rom_bus = next_config_rom_bus;
2508 		next_config_rom = NULL;
2509 	}
2510 
2511 	copy_config_rom(ohci->next_config_rom, config_rom, length);
2512 
2513 	ohci->next_header = config_rom[0];
2514 	ohci->next_config_rom[0] = 0;
2515 
2516 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2517 
2518 	spin_unlock_irq(&ohci->lock);
2519 
2520 	/* If we didn't use the DMA allocation, delete it. */
2521 	if (next_config_rom != NULL)
2522 		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2523 				  next_config_rom, next_config_rom_bus);
2524 
2525 	/*
2526 	 * Now initiate a bus reset to have the changes take
2527 	 * effect. We clean up the old config rom memory and DMA
2528 	 * mappings in the bus reset tasklet, since the OHCI
2529 	 * controller could need to access it before the bus reset
2530 	 * takes effect.
2531 	 */
2532 
2533 	fw_schedule_bus_reset(&ohci->card, true, true);
2534 
2535 	return 0;
2536 }
2537 
2538 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2539 {
2540 	struct fw_ohci *ohci = fw_ohci(card);
2541 
2542 	at_context_transmit(&ohci->at_request_ctx, packet);
2543 }
2544 
2545 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2546 {
2547 	struct fw_ohci *ohci = fw_ohci(card);
2548 
2549 	at_context_transmit(&ohci->at_response_ctx, packet);
2550 }
2551 
2552 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2553 {
2554 	struct fw_ohci *ohci = fw_ohci(card);
2555 	struct context *ctx = &ohci->at_request_ctx;
2556 	struct driver_data *driver_data = packet->driver_data;
2557 	int ret = -ENOENT;
2558 
2559 	tasklet_disable(&ctx->tasklet);
2560 
2561 	if (packet->ack != 0)
2562 		goto out;
2563 
2564 	if (packet->payload_mapped)
2565 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2566 				 packet->payload_length, DMA_TO_DEVICE);
2567 
2568 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2569 	driver_data->packet = NULL;
2570 	packet->ack = RCODE_CANCELLED;
2571 	packet->callback(packet, &ohci->card, packet->ack);
2572 	ret = 0;
2573  out:
2574 	tasklet_enable(&ctx->tasklet);
2575 
2576 	return ret;
2577 }
2578 
2579 static int ohci_enable_phys_dma(struct fw_card *card,
2580 				int node_id, int generation)
2581 {
2582 	struct fw_ohci *ohci = fw_ohci(card);
2583 	unsigned long flags;
2584 	int n, ret = 0;
2585 
2586 	if (param_remote_dma)
2587 		return 0;
2588 
2589 	/*
2590 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2591 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2592 	 */
2593 
2594 	spin_lock_irqsave(&ohci->lock, flags);
2595 
2596 	if (ohci->generation != generation) {
2597 		ret = -ESTALE;
2598 		goto out;
2599 	}
2600 
2601 	/*
2602 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2603 	 * enabled for _all_ nodes on remote buses.
2604 	 */
2605 
2606 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2607 	if (n < 32)
2608 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2609 	else
2610 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2611 
2612 	flush_writes(ohci);
2613  out:
2614 	spin_unlock_irqrestore(&ohci->lock, flags);
2615 
2616 	return ret;
2617 }
2618 
2619 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2620 {
2621 	struct fw_ohci *ohci = fw_ohci(card);
2622 	unsigned long flags;
2623 	u32 value;
2624 
2625 	switch (csr_offset) {
2626 	case CSR_STATE_CLEAR:
2627 	case CSR_STATE_SET:
2628 		if (ohci->is_root &&
2629 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2630 		     OHCI1394_LinkControl_cycleMaster))
2631 			value = CSR_STATE_BIT_CMSTR;
2632 		else
2633 			value = 0;
2634 		if (ohci->csr_state_setclear_abdicate)
2635 			value |= CSR_STATE_BIT_ABDICATE;
2636 
2637 		return value;
2638 
2639 	case CSR_NODE_IDS:
2640 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2641 
2642 	case CSR_CYCLE_TIME:
2643 		return get_cycle_time(ohci);
2644 
2645 	case CSR_BUS_TIME:
2646 		/*
2647 		 * We might be called just after the cycle timer has wrapped
2648 		 * around but just before the cycle64Seconds handler, so we
2649 		 * better check here, too, if the bus time needs to be updated.
2650 		 */
2651 		spin_lock_irqsave(&ohci->lock, flags);
2652 		value = update_bus_time(ohci);
2653 		spin_unlock_irqrestore(&ohci->lock, flags);
2654 		return value;
2655 
2656 	case CSR_BUSY_TIMEOUT:
2657 		value = reg_read(ohci, OHCI1394_ATRetries);
2658 		return (value >> 4) & 0x0ffff00f;
2659 
2660 	case CSR_PRIORITY_BUDGET:
2661 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2662 			(ohci->pri_req_max << 8);
2663 
2664 	default:
2665 		WARN_ON(1);
2666 		return 0;
2667 	}
2668 }
2669 
2670 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2671 {
2672 	struct fw_ohci *ohci = fw_ohci(card);
2673 	unsigned long flags;
2674 
2675 	switch (csr_offset) {
2676 	case CSR_STATE_CLEAR:
2677 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2678 			reg_write(ohci, OHCI1394_LinkControlClear,
2679 				  OHCI1394_LinkControl_cycleMaster);
2680 			flush_writes(ohci);
2681 		}
2682 		if (value & CSR_STATE_BIT_ABDICATE)
2683 			ohci->csr_state_setclear_abdicate = false;
2684 		break;
2685 
2686 	case CSR_STATE_SET:
2687 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2688 			reg_write(ohci, OHCI1394_LinkControlSet,
2689 				  OHCI1394_LinkControl_cycleMaster);
2690 			flush_writes(ohci);
2691 		}
2692 		if (value & CSR_STATE_BIT_ABDICATE)
2693 			ohci->csr_state_setclear_abdicate = true;
2694 		break;
2695 
2696 	case CSR_NODE_IDS:
2697 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2698 		flush_writes(ohci);
2699 		break;
2700 
2701 	case CSR_CYCLE_TIME:
2702 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2703 		reg_write(ohci, OHCI1394_IntEventSet,
2704 			  OHCI1394_cycleInconsistent);
2705 		flush_writes(ohci);
2706 		break;
2707 
2708 	case CSR_BUS_TIME:
2709 		spin_lock_irqsave(&ohci->lock, flags);
2710 		ohci->bus_time = (update_bus_time(ohci) & 0x40) |
2711 		                 (value & ~0x7f);
2712 		spin_unlock_irqrestore(&ohci->lock, flags);
2713 		break;
2714 
2715 	case CSR_BUSY_TIMEOUT:
2716 		value = (value & 0xf) | ((value & 0xf) << 4) |
2717 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2718 		reg_write(ohci, OHCI1394_ATRetries, value);
2719 		flush_writes(ohci);
2720 		break;
2721 
2722 	case CSR_PRIORITY_BUDGET:
2723 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2724 		flush_writes(ohci);
2725 		break;
2726 
2727 	default:
2728 		WARN_ON(1);
2729 		break;
2730 	}
2731 }
2732 
2733 static void flush_iso_completions(struct iso_context *ctx)
2734 {
2735 	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2736 			      ctx->header_length, ctx->header,
2737 			      ctx->base.callback_data);
2738 	ctx->header_length = 0;
2739 }
2740 
2741 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2742 {
2743 	u32 *ctx_hdr;
2744 
2745 	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE) {
2746 		if (ctx->base.drop_overflow_headers)
2747 			return;
2748 		flush_iso_completions(ctx);
2749 	}
2750 
2751 	ctx_hdr = ctx->header + ctx->header_length;
2752 	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2753 
2754 	/*
2755 	 * The two iso header quadlets are byteswapped to little
2756 	 * endian by the controller, but we want to present them
2757 	 * as big endian for consistency with the bus endianness.
2758 	 */
2759 	if (ctx->base.header_size > 0)
2760 		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2761 	if (ctx->base.header_size > 4)
2762 		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2763 	if (ctx->base.header_size > 8)
2764 		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2765 	ctx->header_length += ctx->base.header_size;
2766 }
2767 
2768 static int handle_ir_packet_per_buffer(struct context *context,
2769 				       struct descriptor *d,
2770 				       struct descriptor *last)
2771 {
2772 	struct iso_context *ctx =
2773 		container_of(context, struct iso_context, context);
2774 	struct descriptor *pd;
2775 	u32 buffer_dma;
2776 
2777 	for (pd = d; pd <= last; pd++)
2778 		if (pd->transfer_status)
2779 			break;
2780 	if (pd > last)
2781 		/* Descriptor(s) not done yet, stop iteration */
2782 		return 0;
2783 
2784 	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2785 		d++;
2786 		buffer_dma = le32_to_cpu(d->data_address);
2787 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2788 					      buffer_dma & PAGE_MASK,
2789 					      buffer_dma & ~PAGE_MASK,
2790 					      le16_to_cpu(d->req_count),
2791 					      DMA_FROM_DEVICE);
2792 	}
2793 
2794 	copy_iso_headers(ctx, (u32 *) (last + 1));
2795 
2796 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2797 		flush_iso_completions(ctx);
2798 
2799 	return 1;
2800 }
2801 
2802 /* d == last because each descriptor block is only a single descriptor. */
2803 static int handle_ir_buffer_fill(struct context *context,
2804 				 struct descriptor *d,
2805 				 struct descriptor *last)
2806 {
2807 	struct iso_context *ctx =
2808 		container_of(context, struct iso_context, context);
2809 	unsigned int req_count, res_count, completed;
2810 	u32 buffer_dma;
2811 
2812 	req_count = le16_to_cpu(last->req_count);
2813 	res_count = le16_to_cpu(READ_ONCE(last->res_count));
2814 	completed = req_count - res_count;
2815 	buffer_dma = le32_to_cpu(last->data_address);
2816 
2817 	if (completed > 0) {
2818 		ctx->mc_buffer_bus = buffer_dma;
2819 		ctx->mc_completed = completed;
2820 	}
2821 
2822 	if (res_count != 0)
2823 		/* Descriptor(s) not done yet, stop iteration */
2824 		return 0;
2825 
2826 	dma_sync_single_range_for_cpu(context->ohci->card.device,
2827 				      buffer_dma & PAGE_MASK,
2828 				      buffer_dma & ~PAGE_MASK,
2829 				      completed, DMA_FROM_DEVICE);
2830 
2831 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2832 		ctx->base.callback.mc(&ctx->base,
2833 				      buffer_dma + completed,
2834 				      ctx->base.callback_data);
2835 		ctx->mc_completed = 0;
2836 	}
2837 
2838 	return 1;
2839 }
2840 
2841 static void flush_ir_buffer_fill(struct iso_context *ctx)
2842 {
2843 	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
2844 				      ctx->mc_buffer_bus & PAGE_MASK,
2845 				      ctx->mc_buffer_bus & ~PAGE_MASK,
2846 				      ctx->mc_completed, DMA_FROM_DEVICE);
2847 
2848 	ctx->base.callback.mc(&ctx->base,
2849 			      ctx->mc_buffer_bus + ctx->mc_completed,
2850 			      ctx->base.callback_data);
2851 	ctx->mc_completed = 0;
2852 }
2853 
2854 static inline void sync_it_packet_for_cpu(struct context *context,
2855 					  struct descriptor *pd)
2856 {
2857 	__le16 control;
2858 	u32 buffer_dma;
2859 
2860 	/* only packets beginning with OUTPUT_MORE* have data buffers */
2861 	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2862 		return;
2863 
2864 	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
2865 	pd += 2;
2866 
2867 	/*
2868 	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
2869 	 * data buffer is in the context program's coherent page and must not
2870 	 * be synced.
2871 	 */
2872 	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
2873 	    (context->current_bus          & PAGE_MASK)) {
2874 		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2875 			return;
2876 		pd++;
2877 	}
2878 
2879 	do {
2880 		buffer_dma = le32_to_cpu(pd->data_address);
2881 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2882 					      buffer_dma & PAGE_MASK,
2883 					      buffer_dma & ~PAGE_MASK,
2884 					      le16_to_cpu(pd->req_count),
2885 					      DMA_TO_DEVICE);
2886 		control = pd->control;
2887 		pd++;
2888 	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
2889 }
2890 
2891 static int handle_it_packet(struct context *context,
2892 			    struct descriptor *d,
2893 			    struct descriptor *last)
2894 {
2895 	struct iso_context *ctx =
2896 		container_of(context, struct iso_context, context);
2897 	struct descriptor *pd;
2898 	__be32 *ctx_hdr;
2899 
2900 	for (pd = d; pd <= last; pd++)
2901 		if (pd->transfer_status)
2902 			break;
2903 	if (pd > last)
2904 		/* Descriptor(s) not done yet, stop iteration */
2905 		return 0;
2906 
2907 	sync_it_packet_for_cpu(context, d);
2908 
2909 	if (ctx->header_length + 4 > PAGE_SIZE) {
2910 		if (ctx->base.drop_overflow_headers)
2911 			return 1;
2912 		flush_iso_completions(ctx);
2913 	}
2914 
2915 	ctx_hdr = ctx->header + ctx->header_length;
2916 	ctx->last_timestamp = le16_to_cpu(last->res_count);
2917 	/* Present this value as big-endian to match the receive code */
2918 	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
2919 			       le16_to_cpu(pd->res_count));
2920 	ctx->header_length += 4;
2921 
2922 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2923 		flush_iso_completions(ctx);
2924 
2925 	return 1;
2926 }
2927 
2928 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2929 {
2930 	u32 hi = channels >> 32, lo = channels;
2931 
2932 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2933 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2934 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2935 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2936 	mmiowb();
2937 	ohci->mc_channels = channels;
2938 }
2939 
2940 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2941 				int type, int channel, size_t header_size)
2942 {
2943 	struct fw_ohci *ohci = fw_ohci(card);
2944 	struct iso_context *uninitialized_var(ctx);
2945 	descriptor_callback_t uninitialized_var(callback);
2946 	u64 *uninitialized_var(channels);
2947 	u32 *uninitialized_var(mask), uninitialized_var(regs);
2948 	int index, ret = -EBUSY;
2949 
2950 	spin_lock_irq(&ohci->lock);
2951 
2952 	switch (type) {
2953 	case FW_ISO_CONTEXT_TRANSMIT:
2954 		mask     = &ohci->it_context_mask;
2955 		callback = handle_it_packet;
2956 		index    = ffs(*mask) - 1;
2957 		if (index >= 0) {
2958 			*mask &= ~(1 << index);
2959 			regs = OHCI1394_IsoXmitContextBase(index);
2960 			ctx  = &ohci->it_context_list[index];
2961 		}
2962 		break;
2963 
2964 	case FW_ISO_CONTEXT_RECEIVE:
2965 		channels = &ohci->ir_context_channels;
2966 		mask     = &ohci->ir_context_mask;
2967 		callback = handle_ir_packet_per_buffer;
2968 		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2969 		if (index >= 0) {
2970 			*channels &= ~(1ULL << channel);
2971 			*mask     &= ~(1 << index);
2972 			regs = OHCI1394_IsoRcvContextBase(index);
2973 			ctx  = &ohci->ir_context_list[index];
2974 		}
2975 		break;
2976 
2977 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2978 		mask     = &ohci->ir_context_mask;
2979 		callback = handle_ir_buffer_fill;
2980 		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2981 		if (index >= 0) {
2982 			ohci->mc_allocated = true;
2983 			*mask &= ~(1 << index);
2984 			regs = OHCI1394_IsoRcvContextBase(index);
2985 			ctx  = &ohci->ir_context_list[index];
2986 		}
2987 		break;
2988 
2989 	default:
2990 		index = -1;
2991 		ret = -ENOSYS;
2992 	}
2993 
2994 	spin_unlock_irq(&ohci->lock);
2995 
2996 	if (index < 0)
2997 		return ERR_PTR(ret);
2998 
2999 	memset(ctx, 0, sizeof(*ctx));
3000 	ctx->header_length = 0;
3001 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
3002 	if (ctx->header == NULL) {
3003 		ret = -ENOMEM;
3004 		goto out;
3005 	}
3006 	ret = context_init(&ctx->context, ohci, regs, callback);
3007 	if (ret < 0)
3008 		goto out_with_header;
3009 
3010 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
3011 		set_multichannel_mask(ohci, 0);
3012 		ctx->mc_completed = 0;
3013 	}
3014 
3015 	return &ctx->base;
3016 
3017  out_with_header:
3018 	free_page((unsigned long)ctx->header);
3019  out:
3020 	spin_lock_irq(&ohci->lock);
3021 
3022 	switch (type) {
3023 	case FW_ISO_CONTEXT_RECEIVE:
3024 		*channels |= 1ULL << channel;
3025 		break;
3026 
3027 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3028 		ohci->mc_allocated = false;
3029 		break;
3030 	}
3031 	*mask |= 1 << index;
3032 
3033 	spin_unlock_irq(&ohci->lock);
3034 
3035 	return ERR_PTR(ret);
3036 }
3037 
3038 static int ohci_start_iso(struct fw_iso_context *base,
3039 			  s32 cycle, u32 sync, u32 tags)
3040 {
3041 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3042 	struct fw_ohci *ohci = ctx->context.ohci;
3043 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
3044 	int index;
3045 
3046 	/* the controller cannot start without any queued packets */
3047 	if (ctx->context.last->branch_address == 0)
3048 		return -ENODATA;
3049 
3050 	switch (ctx->base.type) {
3051 	case FW_ISO_CONTEXT_TRANSMIT:
3052 		index = ctx - ohci->it_context_list;
3053 		match = 0;
3054 		if (cycle >= 0)
3055 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3056 				(cycle & 0x7fff) << 16;
3057 
3058 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3059 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3060 		context_run(&ctx->context, match);
3061 		break;
3062 
3063 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3064 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3065 		/* fall through */
3066 	case FW_ISO_CONTEXT_RECEIVE:
3067 		index = ctx - ohci->ir_context_list;
3068 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
3069 		if (cycle >= 0) {
3070 			match |= (cycle & 0x07fff) << 12;
3071 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3072 		}
3073 
3074 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3075 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3076 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3077 		context_run(&ctx->context, control);
3078 
3079 		ctx->sync = sync;
3080 		ctx->tags = tags;
3081 
3082 		break;
3083 	}
3084 
3085 	return 0;
3086 }
3087 
3088 static int ohci_stop_iso(struct fw_iso_context *base)
3089 {
3090 	struct fw_ohci *ohci = fw_ohci(base->card);
3091 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3092 	int index;
3093 
3094 	switch (ctx->base.type) {
3095 	case FW_ISO_CONTEXT_TRANSMIT:
3096 		index = ctx - ohci->it_context_list;
3097 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3098 		break;
3099 
3100 	case FW_ISO_CONTEXT_RECEIVE:
3101 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3102 		index = ctx - ohci->ir_context_list;
3103 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3104 		break;
3105 	}
3106 	flush_writes(ohci);
3107 	context_stop(&ctx->context);
3108 	tasklet_kill(&ctx->context.tasklet);
3109 
3110 	return 0;
3111 }
3112 
3113 static void ohci_free_iso_context(struct fw_iso_context *base)
3114 {
3115 	struct fw_ohci *ohci = fw_ohci(base->card);
3116 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3117 	unsigned long flags;
3118 	int index;
3119 
3120 	ohci_stop_iso(base);
3121 	context_release(&ctx->context);
3122 	free_page((unsigned long)ctx->header);
3123 
3124 	spin_lock_irqsave(&ohci->lock, flags);
3125 
3126 	switch (base->type) {
3127 	case FW_ISO_CONTEXT_TRANSMIT:
3128 		index = ctx - ohci->it_context_list;
3129 		ohci->it_context_mask |= 1 << index;
3130 		break;
3131 
3132 	case FW_ISO_CONTEXT_RECEIVE:
3133 		index = ctx - ohci->ir_context_list;
3134 		ohci->ir_context_mask |= 1 << index;
3135 		ohci->ir_context_channels |= 1ULL << base->channel;
3136 		break;
3137 
3138 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3139 		index = ctx - ohci->ir_context_list;
3140 		ohci->ir_context_mask |= 1 << index;
3141 		ohci->ir_context_channels |= ohci->mc_channels;
3142 		ohci->mc_channels = 0;
3143 		ohci->mc_allocated = false;
3144 		break;
3145 	}
3146 
3147 	spin_unlock_irqrestore(&ohci->lock, flags);
3148 }
3149 
3150 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3151 {
3152 	struct fw_ohci *ohci = fw_ohci(base->card);
3153 	unsigned long flags;
3154 	int ret;
3155 
3156 	switch (base->type) {
3157 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3158 
3159 		spin_lock_irqsave(&ohci->lock, flags);
3160 
3161 		/* Don't allow multichannel to grab other contexts' channels. */
3162 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3163 			*channels = ohci->ir_context_channels;
3164 			ret = -EBUSY;
3165 		} else {
3166 			set_multichannel_mask(ohci, *channels);
3167 			ret = 0;
3168 		}
3169 
3170 		spin_unlock_irqrestore(&ohci->lock, flags);
3171 
3172 		break;
3173 	default:
3174 		ret = -EINVAL;
3175 	}
3176 
3177 	return ret;
3178 }
3179 
3180 #ifdef CONFIG_PM
3181 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3182 {
3183 	int i;
3184 	struct iso_context *ctx;
3185 
3186 	for (i = 0 ; i < ohci->n_ir ; i++) {
3187 		ctx = &ohci->ir_context_list[i];
3188 		if (ctx->context.running)
3189 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3190 	}
3191 
3192 	for (i = 0 ; i < ohci->n_it ; i++) {
3193 		ctx = &ohci->it_context_list[i];
3194 		if (ctx->context.running)
3195 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3196 	}
3197 }
3198 #endif
3199 
3200 static int queue_iso_transmit(struct iso_context *ctx,
3201 			      struct fw_iso_packet *packet,
3202 			      struct fw_iso_buffer *buffer,
3203 			      unsigned long payload)
3204 {
3205 	struct descriptor *d, *last, *pd;
3206 	struct fw_iso_packet *p;
3207 	__le32 *header;
3208 	dma_addr_t d_bus, page_bus;
3209 	u32 z, header_z, payload_z, irq;
3210 	u32 payload_index, payload_end_index, next_page_index;
3211 	int page, end_page, i, length, offset;
3212 
3213 	p = packet;
3214 	payload_index = payload;
3215 
3216 	if (p->skip)
3217 		z = 1;
3218 	else
3219 		z = 2;
3220 	if (p->header_length > 0)
3221 		z++;
3222 
3223 	/* Determine the first page the payload isn't contained in. */
3224 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3225 	if (p->payload_length > 0)
3226 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
3227 	else
3228 		payload_z = 0;
3229 
3230 	z += payload_z;
3231 
3232 	/* Get header size in number of descriptors. */
3233 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3234 
3235 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3236 	if (d == NULL)
3237 		return -ENOMEM;
3238 
3239 	if (!p->skip) {
3240 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3241 		d[0].req_count = cpu_to_le16(8);
3242 		/*
3243 		 * Link the skip address to this descriptor itself.  This causes
3244 		 * a context to skip a cycle whenever lost cycles or FIFO
3245 		 * overruns occur, without dropping the data.  The application
3246 		 * should then decide whether this is an error condition or not.
3247 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
3248 		 */
3249 		d[0].branch_address = cpu_to_le32(d_bus | z);
3250 
3251 		header = (__le32 *) &d[1];
3252 		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
3253 					IT_HEADER_TAG(p->tag) |
3254 					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
3255 					IT_HEADER_CHANNEL(ctx->base.channel) |
3256 					IT_HEADER_SPEED(ctx->base.speed));
3257 		header[1] =
3258 			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
3259 							  p->payload_length));
3260 	}
3261 
3262 	if (p->header_length > 0) {
3263 		d[2].req_count    = cpu_to_le16(p->header_length);
3264 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3265 		memcpy(&d[z], p->header, p->header_length);
3266 	}
3267 
3268 	pd = d + z - payload_z;
3269 	payload_end_index = payload_index + p->payload_length;
3270 	for (i = 0; i < payload_z; i++) {
3271 		page               = payload_index >> PAGE_SHIFT;
3272 		offset             = payload_index & ~PAGE_MASK;
3273 		next_page_index    = (page + 1) << PAGE_SHIFT;
3274 		length             =
3275 			min(next_page_index, payload_end_index) - payload_index;
3276 		pd[i].req_count    = cpu_to_le16(length);
3277 
3278 		page_bus = page_private(buffer->pages[page]);
3279 		pd[i].data_address = cpu_to_le32(page_bus + offset);
3280 
3281 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3282 						 page_bus, offset, length,
3283 						 DMA_TO_DEVICE);
3284 
3285 		payload_index += length;
3286 	}
3287 
3288 	if (p->interrupt)
3289 		irq = DESCRIPTOR_IRQ_ALWAYS;
3290 	else
3291 		irq = DESCRIPTOR_NO_IRQ;
3292 
3293 	last = z == 2 ? d : d + z - 1;
3294 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3295 				     DESCRIPTOR_STATUS |
3296 				     DESCRIPTOR_BRANCH_ALWAYS |
3297 				     irq);
3298 
3299 	context_append(&ctx->context, d, z, header_z);
3300 
3301 	return 0;
3302 }
3303 
3304 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3305 				       struct fw_iso_packet *packet,
3306 				       struct fw_iso_buffer *buffer,
3307 				       unsigned long payload)
3308 {
3309 	struct device *device = ctx->context.ohci->card.device;
3310 	struct descriptor *d, *pd;
3311 	dma_addr_t d_bus, page_bus;
3312 	u32 z, header_z, rest;
3313 	int i, j, length;
3314 	int page, offset, packet_count, header_size, payload_per_buffer;
3315 
3316 	/*
3317 	 * The OHCI controller puts the isochronous header and trailer in the
3318 	 * buffer, so we need at least 8 bytes.
3319 	 */
3320 	packet_count = packet->header_length / ctx->base.header_size;
3321 	header_size  = max(ctx->base.header_size, (size_t)8);
3322 
3323 	/* Get header size in number of descriptors. */
3324 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3325 	page     = payload >> PAGE_SHIFT;
3326 	offset   = payload & ~PAGE_MASK;
3327 	payload_per_buffer = packet->payload_length / packet_count;
3328 
3329 	for (i = 0; i < packet_count; i++) {
3330 		/* d points to the header descriptor */
3331 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3332 		d = context_get_descriptors(&ctx->context,
3333 				z + header_z, &d_bus);
3334 		if (d == NULL)
3335 			return -ENOMEM;
3336 
3337 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3338 					      DESCRIPTOR_INPUT_MORE);
3339 		if (packet->skip && i == 0)
3340 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3341 		d->req_count    = cpu_to_le16(header_size);
3342 		d->res_count    = d->req_count;
3343 		d->transfer_status = 0;
3344 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3345 
3346 		rest = payload_per_buffer;
3347 		pd = d;
3348 		for (j = 1; j < z; j++) {
3349 			pd++;
3350 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3351 						  DESCRIPTOR_INPUT_MORE);
3352 
3353 			if (offset + rest < PAGE_SIZE)
3354 				length = rest;
3355 			else
3356 				length = PAGE_SIZE - offset;
3357 			pd->req_count = cpu_to_le16(length);
3358 			pd->res_count = pd->req_count;
3359 			pd->transfer_status = 0;
3360 
3361 			page_bus = page_private(buffer->pages[page]);
3362 			pd->data_address = cpu_to_le32(page_bus + offset);
3363 
3364 			dma_sync_single_range_for_device(device, page_bus,
3365 							 offset, length,
3366 							 DMA_FROM_DEVICE);
3367 
3368 			offset = (offset + length) & ~PAGE_MASK;
3369 			rest -= length;
3370 			if (offset == 0)
3371 				page++;
3372 		}
3373 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3374 					  DESCRIPTOR_INPUT_LAST |
3375 					  DESCRIPTOR_BRANCH_ALWAYS);
3376 		if (packet->interrupt && i == packet_count - 1)
3377 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3378 
3379 		context_append(&ctx->context, d, z, header_z);
3380 	}
3381 
3382 	return 0;
3383 }
3384 
3385 static int queue_iso_buffer_fill(struct iso_context *ctx,
3386 				 struct fw_iso_packet *packet,
3387 				 struct fw_iso_buffer *buffer,
3388 				 unsigned long payload)
3389 {
3390 	struct descriptor *d;
3391 	dma_addr_t d_bus, page_bus;
3392 	int page, offset, rest, z, i, length;
3393 
3394 	page   = payload >> PAGE_SHIFT;
3395 	offset = payload & ~PAGE_MASK;
3396 	rest   = packet->payload_length;
3397 
3398 	/* We need one descriptor for each page in the buffer. */
3399 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3400 
3401 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3402 		return -EFAULT;
3403 
3404 	for (i = 0; i < z; i++) {
3405 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3406 		if (d == NULL)
3407 			return -ENOMEM;
3408 
3409 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3410 					 DESCRIPTOR_BRANCH_ALWAYS);
3411 		if (packet->skip && i == 0)
3412 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3413 		if (packet->interrupt && i == z - 1)
3414 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3415 
3416 		if (offset + rest < PAGE_SIZE)
3417 			length = rest;
3418 		else
3419 			length = PAGE_SIZE - offset;
3420 		d->req_count = cpu_to_le16(length);
3421 		d->res_count = d->req_count;
3422 		d->transfer_status = 0;
3423 
3424 		page_bus = page_private(buffer->pages[page]);
3425 		d->data_address = cpu_to_le32(page_bus + offset);
3426 
3427 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3428 						 page_bus, offset, length,
3429 						 DMA_FROM_DEVICE);
3430 
3431 		rest -= length;
3432 		offset = 0;
3433 		page++;
3434 
3435 		context_append(&ctx->context, d, 1, 0);
3436 	}
3437 
3438 	return 0;
3439 }
3440 
3441 static int ohci_queue_iso(struct fw_iso_context *base,
3442 			  struct fw_iso_packet *packet,
3443 			  struct fw_iso_buffer *buffer,
3444 			  unsigned long payload)
3445 {
3446 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3447 	unsigned long flags;
3448 	int ret = -ENOSYS;
3449 
3450 	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3451 	switch (base->type) {
3452 	case FW_ISO_CONTEXT_TRANSMIT:
3453 		ret = queue_iso_transmit(ctx, packet, buffer, payload);
3454 		break;
3455 	case FW_ISO_CONTEXT_RECEIVE:
3456 		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3457 		break;
3458 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3459 		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3460 		break;
3461 	}
3462 	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3463 
3464 	return ret;
3465 }
3466 
3467 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3468 {
3469 	struct context *ctx =
3470 			&container_of(base, struct iso_context, base)->context;
3471 
3472 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3473 }
3474 
3475 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3476 {
3477 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3478 	int ret = 0;
3479 
3480 	tasklet_disable(&ctx->context.tasklet);
3481 
3482 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3483 		context_tasklet((unsigned long)&ctx->context);
3484 
3485 		switch (base->type) {
3486 		case FW_ISO_CONTEXT_TRANSMIT:
3487 		case FW_ISO_CONTEXT_RECEIVE:
3488 			if (ctx->header_length != 0)
3489 				flush_iso_completions(ctx);
3490 			break;
3491 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3492 			if (ctx->mc_completed != 0)
3493 				flush_ir_buffer_fill(ctx);
3494 			break;
3495 		default:
3496 			ret = -ENOSYS;
3497 		}
3498 
3499 		clear_bit_unlock(0, &ctx->flushing_completions);
3500 		smp_mb__after_atomic();
3501 	}
3502 
3503 	tasklet_enable(&ctx->context.tasklet);
3504 
3505 	return ret;
3506 }
3507 
3508 static const struct fw_card_driver ohci_driver = {
3509 	.enable			= ohci_enable,
3510 	.read_phy_reg		= ohci_read_phy_reg,
3511 	.update_phy_reg		= ohci_update_phy_reg,
3512 	.set_config_rom		= ohci_set_config_rom,
3513 	.send_request		= ohci_send_request,
3514 	.send_response		= ohci_send_response,
3515 	.cancel_packet		= ohci_cancel_packet,
3516 	.enable_phys_dma	= ohci_enable_phys_dma,
3517 	.read_csr		= ohci_read_csr,
3518 	.write_csr		= ohci_write_csr,
3519 
3520 	.allocate_iso_context	= ohci_allocate_iso_context,
3521 	.free_iso_context	= ohci_free_iso_context,
3522 	.set_iso_channels	= ohci_set_iso_channels,
3523 	.queue_iso		= ohci_queue_iso,
3524 	.flush_queue_iso	= ohci_flush_queue_iso,
3525 	.flush_iso_completions	= ohci_flush_iso_completions,
3526 	.start_iso		= ohci_start_iso,
3527 	.stop_iso		= ohci_stop_iso,
3528 };
3529 
3530 #ifdef CONFIG_PPC_PMAC
3531 static void pmac_ohci_on(struct pci_dev *dev)
3532 {
3533 	if (machine_is(powermac)) {
3534 		struct device_node *ofn = pci_device_to_OF_node(dev);
3535 
3536 		if (ofn) {
3537 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3538 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3539 		}
3540 	}
3541 }
3542 
3543 static void pmac_ohci_off(struct pci_dev *dev)
3544 {
3545 	if (machine_is(powermac)) {
3546 		struct device_node *ofn = pci_device_to_OF_node(dev);
3547 
3548 		if (ofn) {
3549 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3550 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3551 		}
3552 	}
3553 }
3554 #else
3555 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3556 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3557 #endif /* CONFIG_PPC_PMAC */
3558 
3559 static int pci_probe(struct pci_dev *dev,
3560 			       const struct pci_device_id *ent)
3561 {
3562 	struct fw_ohci *ohci;
3563 	u32 bus_options, max_receive, link_speed, version;
3564 	u64 guid;
3565 	int i, err;
3566 	size_t size;
3567 
3568 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3569 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3570 		return -ENOSYS;
3571 	}
3572 
3573 	ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3574 	if (ohci == NULL) {
3575 		err = -ENOMEM;
3576 		goto fail;
3577 	}
3578 
3579 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3580 
3581 	pmac_ohci_on(dev);
3582 
3583 	err = pci_enable_device(dev);
3584 	if (err) {
3585 		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3586 		goto fail_free;
3587 	}
3588 
3589 	pci_set_master(dev);
3590 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3591 	pci_set_drvdata(dev, ohci);
3592 
3593 	spin_lock_init(&ohci->lock);
3594 	mutex_init(&ohci->phy_reg_mutex);
3595 
3596 	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3597 
3598 	if (!(pci_resource_flags(dev, 0) & IORESOURCE_MEM) ||
3599 	    pci_resource_len(dev, 0) < OHCI1394_REGISTER_SIZE) {
3600 		ohci_err(ohci, "invalid MMIO resource\n");
3601 		err = -ENXIO;
3602 		goto fail_disable;
3603 	}
3604 
3605 	err = pci_request_region(dev, 0, ohci_driver_name);
3606 	if (err) {
3607 		ohci_err(ohci, "MMIO resource unavailable\n");
3608 		goto fail_disable;
3609 	}
3610 
3611 	ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3612 	if (ohci->registers == NULL) {
3613 		ohci_err(ohci, "failed to remap registers\n");
3614 		err = -ENXIO;
3615 		goto fail_iomem;
3616 	}
3617 
3618 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3619 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3620 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3621 		     ohci_quirks[i].device == dev->device) &&
3622 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3623 		     ohci_quirks[i].revision >= dev->revision)) {
3624 			ohci->quirks = ohci_quirks[i].flags;
3625 			break;
3626 		}
3627 	if (param_quirks)
3628 		ohci->quirks = param_quirks;
3629 
3630 	/*
3631 	 * Because dma_alloc_coherent() allocates at least one page,
3632 	 * we save space by using a common buffer for the AR request/
3633 	 * response descriptors and the self IDs buffer.
3634 	 */
3635 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3636 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3637 	ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3638 					       PAGE_SIZE,
3639 					       &ohci->misc_buffer_bus,
3640 					       GFP_KERNEL);
3641 	if (!ohci->misc_buffer) {
3642 		err = -ENOMEM;
3643 		goto fail_iounmap;
3644 	}
3645 
3646 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3647 			      OHCI1394_AsReqRcvContextControlSet);
3648 	if (err < 0)
3649 		goto fail_misc_buf;
3650 
3651 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3652 			      OHCI1394_AsRspRcvContextControlSet);
3653 	if (err < 0)
3654 		goto fail_arreq_ctx;
3655 
3656 	err = context_init(&ohci->at_request_ctx, ohci,
3657 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3658 	if (err < 0)
3659 		goto fail_arrsp_ctx;
3660 
3661 	err = context_init(&ohci->at_response_ctx, ohci,
3662 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3663 	if (err < 0)
3664 		goto fail_atreq_ctx;
3665 
3666 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3667 	ohci->ir_context_channels = ~0ULL;
3668 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3669 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3670 	ohci->ir_context_mask = ohci->ir_context_support;
3671 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3672 	size = sizeof(struct iso_context) * ohci->n_ir;
3673 	ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3674 
3675 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3676 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3677 	/* JMicron JMB38x often shows 0 at first read, just ignore it */
3678 	if (!ohci->it_context_support) {
3679 		ohci_notice(ohci, "overriding IsoXmitIntMask\n");
3680 		ohci->it_context_support = 0xf;
3681 	}
3682 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3683 	ohci->it_context_mask = ohci->it_context_support;
3684 	ohci->n_it = hweight32(ohci->it_context_mask);
3685 	size = sizeof(struct iso_context) * ohci->n_it;
3686 	ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3687 
3688 	if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3689 		err = -ENOMEM;
3690 		goto fail_contexts;
3691 	}
3692 
3693 	ohci->self_id     = ohci->misc_buffer     + PAGE_SIZE/2;
3694 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3695 
3696 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3697 	max_receive = (bus_options >> 12) & 0xf;
3698 	link_speed = bus_options & 0x7;
3699 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3700 		reg_read(ohci, OHCI1394_GUIDLo);
3701 
3702 	if (!(ohci->quirks & QUIRK_NO_MSI))
3703 		pci_enable_msi(dev);
3704 	if (request_irq(dev->irq, irq_handler,
3705 			pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
3706 			ohci_driver_name, ohci)) {
3707 		ohci_err(ohci, "failed to allocate interrupt %d\n", dev->irq);
3708 		err = -EIO;
3709 		goto fail_msi;
3710 	}
3711 
3712 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3713 	if (err)
3714 		goto fail_irq;
3715 
3716 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3717 	ohci_notice(ohci,
3718 		    "added OHCI v%x.%x device as card %d, "
3719 		    "%d IR + %d IT contexts, quirks 0x%x%s\n",
3720 		    version >> 16, version & 0xff, ohci->card.index,
3721 		    ohci->n_ir, ohci->n_it, ohci->quirks,
3722 		    reg_read(ohci, OHCI1394_PhyUpperBound) ?
3723 			", physUB" : "");
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 static int __init fw_ohci_init(void)
3874 {
3875 	selfid_workqueue = alloc_workqueue(KBUILD_MODNAME, WQ_MEM_RECLAIM, 0);
3876 	if (!selfid_workqueue)
3877 		return -ENOMEM;
3878 
3879 	return pci_register_driver(&fw_ohci_pci_driver);
3880 }
3881 
3882 static void __exit fw_ohci_cleanup(void)
3883 {
3884 	pci_unregister_driver(&fw_ohci_pci_driver);
3885 	destroy_workqueue(selfid_workqueue);
3886 }
3887 
3888 module_init(fw_ohci_init);
3889 module_exit(fw_ohci_cleanup);
3890 
3891 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3892 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3893 MODULE_LICENSE("GPL");
3894 
3895 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3896 MODULE_ALIAS("ohci1394");
3897