xref: /linux/drivers/firewire/ohci.c (revision 5c49cc0ed405cadb60d8c4484f95ffdaf7c6ec5c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for OHCI 1394 controllers
4  *
5  * Copyright (C) 2003-2006 Kristian Hoegsberg <krh@bitplanet.net>
6  */
7 
8 #include <linux/bitops.h>
9 #include <linux/bug.h>
10 #include <linux/compiler.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/firewire.h>
15 #include <linux/firewire-constants.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/list.h>
21 #include <linux/mm.h>
22 #include <linux/module.h>
23 #include <linux/moduleparam.h>
24 #include <linux/mutex.h>
25 #include <linux/pci.h>
26 #include <linux/pci_ids.h>
27 #include <linux/slab.h>
28 #include <linux/spinlock.h>
29 #include <linux/string.h>
30 #include <linux/time.h>
31 #include <linux/vmalloc.h>
32 #include <linux/workqueue.h>
33 
34 #include <asm/byteorder.h>
35 #include <asm/page.h>
36 
37 #ifdef CONFIG_PPC_PMAC
38 #include <asm/pmac_feature.h>
39 #endif
40 
41 #include "core.h"
42 #include "ohci.h"
43 #include "packet-header-definitions.h"
44 #include "phy-packet-definitions.h"
45 
46 #include <trace/events/firewire.h>
47 
48 static u32 cond_le32_to_cpu(__le32 value, bool has_be_header_quirk);
49 
50 #define CREATE_TRACE_POINTS
51 #include <trace/events/firewire_ohci.h>
52 
53 #define ohci_notice(ohci, f, args...)	dev_notice(ohci->card.device, f, ##args)
54 #define ohci_err(ohci, f, args...)	dev_err(ohci->card.device, f, ##args)
55 
56 #define DESCRIPTOR_OUTPUT_MORE		0
57 #define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
58 #define DESCRIPTOR_INPUT_MORE		(2 << 12)
59 #define DESCRIPTOR_INPUT_LAST		(3 << 12)
60 #define DESCRIPTOR_STATUS		(1 << 11)
61 #define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
62 #define DESCRIPTOR_PING			(1 << 7)
63 #define DESCRIPTOR_YY			(1 << 6)
64 #define DESCRIPTOR_NO_IRQ		(0 << 4)
65 #define DESCRIPTOR_IRQ_ERROR		(1 << 4)
66 #define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
67 #define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
68 #define DESCRIPTOR_WAIT			(3 << 0)
69 
70 #define DESCRIPTOR_CMD			(0xf << 12)
71 
72 struct descriptor {
73 	__le16 req_count;
74 	__le16 control;
75 	__le32 data_address;
76 	__le32 branch_address;
77 	__le16 res_count;
78 	__le16 transfer_status;
79 } __aligned(16);
80 
81 #define CONTROL_SET(regs)	(regs)
82 #define CONTROL_CLEAR(regs)	((regs) + 4)
83 #define COMMAND_PTR(regs)	((regs) + 12)
84 #define CONTEXT_MATCH(regs)	((regs) + 16)
85 
86 #define AR_BUFFER_SIZE	(32*1024)
87 #define AR_BUFFERS_MIN	DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
88 /* we need at least two pages for proper list management */
89 #define AR_BUFFERS	(AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)
90 
91 #define MAX_ASYNC_PAYLOAD	4096
92 #define MAX_AR_PACKET_SIZE	(16 + MAX_ASYNC_PAYLOAD + 4)
93 #define AR_WRAPAROUND_PAGES	DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)
94 
95 struct ar_context {
96 	struct fw_ohci *ohci;
97 	struct page *pages[AR_BUFFERS];
98 	void *buffer;
99 	struct descriptor *descriptors;
100 	dma_addr_t descriptors_bus;
101 	void *pointer;
102 	unsigned int last_buffer_index;
103 	u32 regs;
104 	struct tasklet_struct tasklet;
105 };
106 
107 struct context;
108 
109 typedef int (*descriptor_callback_t)(struct context *ctx,
110 				     struct descriptor *d,
111 				     struct descriptor *last);
112 
113 /*
114  * A buffer that contains a block of DMA-able coherent memory used for
115  * storing a portion of a DMA descriptor program.
116  */
117 struct descriptor_buffer {
118 	struct list_head list;
119 	dma_addr_t buffer_bus;
120 	size_t buffer_size;
121 	size_t used;
122 	struct descriptor buffer[];
123 };
124 
125 struct context {
126 	struct fw_ohci *ohci;
127 	u32 regs;
128 	int total_allocation;
129 	u32 current_bus;
130 	bool running;
131 	bool flushing;
132 
133 	/*
134 	 * List of page-sized buffers for storing DMA descriptors.
135 	 * Head of list contains buffers in use and tail of list contains
136 	 * free buffers.
137 	 */
138 	struct list_head buffer_list;
139 
140 	/*
141 	 * Pointer to a buffer inside buffer_list that contains the tail
142 	 * end of the current DMA program.
143 	 */
144 	struct descriptor_buffer *buffer_tail;
145 
146 	/*
147 	 * The descriptor containing the branch address of the first
148 	 * descriptor that has not yet been filled by the device.
149 	 */
150 	struct descriptor *last;
151 
152 	/*
153 	 * The last descriptor block in the DMA program. It contains the branch
154 	 * address that must be updated upon appending a new descriptor.
155 	 */
156 	struct descriptor *prev;
157 	int prev_z;
158 
159 	descriptor_callback_t callback;
160 
161 	struct tasklet_struct tasklet;
162 };
163 
164 struct iso_context {
165 	struct fw_iso_context base;
166 	struct context context;
167 	void *header;
168 	size_t header_length;
169 	unsigned long flushing_completions;
170 	u32 mc_buffer_bus;
171 	u16 mc_completed;
172 	u16 last_timestamp;
173 	u8 sync;
174 	u8 tags;
175 };
176 
177 #define CONFIG_ROM_SIZE		(CSR_CONFIG_ROM_END - CSR_CONFIG_ROM)
178 
179 struct fw_ohci {
180 	struct fw_card card;
181 
182 	__iomem char *registers;
183 	int node_id;
184 	int generation;
185 	int request_generation;	/* for timestamping incoming requests */
186 	unsigned quirks;
187 	unsigned int pri_req_max;
188 	u32 bus_time;
189 	bool bus_time_running;
190 	bool is_root;
191 	bool csr_state_setclear_abdicate;
192 	int n_ir;
193 	int n_it;
194 	/*
195 	 * Spinlock for accessing fw_ohci data.  Never call out of
196 	 * this driver with this lock held.
197 	 */
198 	spinlock_t lock;
199 
200 	struct mutex phy_reg_mutex;
201 
202 	void *misc_buffer;
203 	dma_addr_t misc_buffer_bus;
204 
205 	struct ar_context ar_request_ctx;
206 	struct ar_context ar_response_ctx;
207 	struct context at_request_ctx;
208 	struct context at_response_ctx;
209 
210 	u32 it_context_support;
211 	u32 it_context_mask;     /* unoccupied IT contexts */
212 	struct iso_context *it_context_list;
213 	u64 ir_context_channels; /* unoccupied channels */
214 	u32 ir_context_support;
215 	u32 ir_context_mask;     /* unoccupied IR contexts */
216 	struct iso_context *ir_context_list;
217 	u64 mc_channels; /* channels in use by the multichannel IR context */
218 	bool mc_allocated;
219 
220 	__be32    *config_rom;
221 	dma_addr_t config_rom_bus;
222 	__be32    *next_config_rom;
223 	dma_addr_t next_config_rom_bus;
224 	__be32     next_header;
225 
226 	__le32    *self_id;
227 	dma_addr_t self_id_bus;
228 	struct work_struct bus_reset_work;
229 
230 	u32 self_id_buffer[512];
231 };
232 
233 static struct workqueue_struct *selfid_workqueue;
234 
235 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
236 {
237 	return container_of(card, struct fw_ohci, card);
238 }
239 
240 #define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
241 #define IR_CONTEXT_BUFFER_FILL		0x80000000
242 #define IR_CONTEXT_ISOCH_HEADER		0x40000000
243 #define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
244 #define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
245 #define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000
246 
247 #define CONTEXT_RUN	0x8000
248 #define CONTEXT_WAKE	0x1000
249 #define CONTEXT_DEAD	0x0800
250 #define CONTEXT_ACTIVE	0x0400
251 
252 #define OHCI1394_MAX_AT_REQ_RETRIES	0xf
253 #define OHCI1394_MAX_AT_RESP_RETRIES	0x2
254 #define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8
255 
256 #define OHCI1394_REGISTER_SIZE		0x800
257 #define OHCI1394_PCI_HCI_Control	0x40
258 #define SELF_ID_BUF_SIZE		0x800
259 #define OHCI_VERSION_1_1		0x010010
260 
261 static char ohci_driver_name[] = KBUILD_MODNAME;
262 
263 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
264 #define PCI_DEVICE_ID_AGERE_FW643	0x5901
265 #define PCI_DEVICE_ID_CREATIVE_SB1394	0x4001
266 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
267 #define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
268 #define PCI_DEVICE_ID_TI_TSB12LV26	0x8020
269 #define PCI_DEVICE_ID_TI_TSB82AA2	0x8025
270 #define PCI_DEVICE_ID_VIA_VT630X	0x3044
271 #define PCI_REV_ID_VIA_VT6306		0x46
272 #define PCI_DEVICE_ID_VIA_VT6315	0x3403
273 
274 #define QUIRK_CYCLE_TIMER		0x1
275 #define QUIRK_RESET_PACKET		0x2
276 #define QUIRK_BE_HEADERS		0x4
277 #define QUIRK_NO_1394A			0x8
278 #define QUIRK_NO_MSI			0x10
279 #define QUIRK_TI_SLLZ059		0x20
280 #define QUIRK_IR_WAKE			0x40
281 
282 // On PCI Express Root Complex in any type of AMD Ryzen machine, VIA VT6306/6307/6308 with Asmedia
283 // ASM1083/1085 brings an inconvenience that the read accesses to 'Isochronous Cycle Timer' register
284 // (at offset 0xf0 in PCI I/O space) often causes unexpected system reboot. The mechanism is not
285 // clear, since the read access to the other registers is enough safe; e.g. 'Node ID' register,
286 // while it is probable due to detection of any type of PCIe error.
287 #define QUIRK_REBOOT_BY_CYCLE_TIMER_READ	0x80000000
288 
289 #if IS_ENABLED(CONFIG_X86)
290 
291 static bool has_reboot_by_cycle_timer_read_quirk(const struct fw_ohci *ohci)
292 {
293 	return !!(ohci->quirks & QUIRK_REBOOT_BY_CYCLE_TIMER_READ);
294 }
295 
296 #define PCI_DEVICE_ID_ASMEDIA_ASM108X	0x1080
297 
298 static bool detect_vt630x_with_asm1083_on_amd_ryzen_machine(const struct pci_dev *pdev)
299 {
300 	const struct pci_dev *pcie_to_pci_bridge;
301 
302 	// Detect any type of AMD Ryzen machine.
303 	if (!static_cpu_has(X86_FEATURE_ZEN))
304 		return false;
305 
306 	// Detect VIA VT6306/6307/6308.
307 	if (pdev->vendor != PCI_VENDOR_ID_VIA)
308 		return false;
309 	if (pdev->device != PCI_DEVICE_ID_VIA_VT630X)
310 		return false;
311 
312 	// Detect Asmedia ASM1083/1085.
313 	pcie_to_pci_bridge = pdev->bus->self;
314 	if (pcie_to_pci_bridge->vendor != PCI_VENDOR_ID_ASMEDIA)
315 		return false;
316 	if (pcie_to_pci_bridge->device != PCI_DEVICE_ID_ASMEDIA_ASM108X)
317 		return false;
318 
319 	return true;
320 }
321 
322 #else
323 #define has_reboot_by_cycle_timer_read_quirk(ohci) false
324 #define detect_vt630x_with_asm1083_on_amd_ryzen_machine(pdev)	false
325 #endif
326 
327 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
328 static const struct {
329 	unsigned short vendor, device, revision, flags;
330 } ohci_quirks[] = {
331 	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
332 		QUIRK_CYCLE_TIMER},
333 
334 	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
335 		QUIRK_BE_HEADERS},
336 
337 	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
338 		QUIRK_NO_MSI},
339 
340 	{PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
341 		QUIRK_RESET_PACKET},
342 
343 	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
344 		QUIRK_NO_MSI},
345 
346 	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
347 		QUIRK_CYCLE_TIMER},
348 
349 	{PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
350 		QUIRK_NO_MSI},
351 
352 	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
353 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
354 
355 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
356 		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
357 
358 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
359 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
360 
361 	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
362 		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
363 
364 	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
365 		QUIRK_RESET_PACKET},
366 
367 	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT630X, PCI_REV_ID_VIA_VT6306,
368 		QUIRK_CYCLE_TIMER | QUIRK_IR_WAKE},
369 
370 	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, 0,
371 		QUIRK_CYCLE_TIMER /* FIXME: necessary? */ | QUIRK_NO_MSI},
372 
373 	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, PCI_ANY_ID,
374 		QUIRK_NO_MSI},
375 
376 	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
377 		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
378 };
379 
380 /* This overrides anything that was found in ohci_quirks[]. */
381 static int param_quirks;
382 module_param_named(quirks, param_quirks, int, 0644);
383 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
384 	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
385 	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
386 	", AR/selfID endianness = "	__stringify(QUIRK_BE_HEADERS)
387 	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
388 	", disable MSI = "		__stringify(QUIRK_NO_MSI)
389 	", TI SLLZ059 erratum = "	__stringify(QUIRK_TI_SLLZ059)
390 	", IR wake unreliable = "	__stringify(QUIRK_IR_WAKE)
391 	")");
392 
393 #define OHCI_PARAM_DEBUG_AT_AR		1
394 #define OHCI_PARAM_DEBUG_SELFIDS	2
395 #define OHCI_PARAM_DEBUG_IRQS		4
396 
397 static int param_debug;
398 module_param_named(debug, param_debug, int, 0644);
399 MODULE_PARM_DESC(debug, "Verbose logging, deprecated in v6.11 kernel or later. (default = 0"
400 	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
401 	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
402 	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
403 	", or a combination, or all = -1)");
404 
405 static bool param_remote_dma;
406 module_param_named(remote_dma, param_remote_dma, bool, 0444);
407 MODULE_PARM_DESC(remote_dma, "Enable unfiltered remote DMA (default = N)");
408 
409 static void log_irqs(struct fw_ohci *ohci, u32 evt)
410 {
411 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_IRQS)))
412 		return;
413 
414 	ohci_notice(ohci, "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
415 	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
416 	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
417 	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
418 	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
419 	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
420 	    evt & OHCI1394_isochRx		? " IR"			: "",
421 	    evt & OHCI1394_isochTx		? " IT"			: "",
422 	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
423 	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
424 	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
425 	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
426 	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
427 	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
428 	    evt & OHCI1394_busReset		? " busReset"		: "",
429 	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
430 		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
431 		    OHCI1394_respTxComplete | OHCI1394_isochRx |
432 		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
433 		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
434 		    OHCI1394_cycleInconsistent |
435 		    OHCI1394_regAccessFail | OHCI1394_busReset)
436 						? " ?"			: "");
437 }
438 
439 static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
440 {
441 	static const char *const speed[] = {
442 		[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
443 	};
444 	static const char *const power[] = {
445 		[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
446 		[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
447 	};
448 	static const char port[] = {
449 		[PHY_PACKET_SELF_ID_PORT_STATUS_NONE] = '.',
450 		[PHY_PACKET_SELF_ID_PORT_STATUS_NCONN] = '-',
451 		[PHY_PACKET_SELF_ID_PORT_STATUS_PARENT] = 'p',
452 		[PHY_PACKET_SELF_ID_PORT_STATUS_CHILD] = 'c',
453 	};
454 	struct self_id_sequence_enumerator enumerator = {
455 		.cursor = ohci->self_id_buffer,
456 		.quadlet_count = self_id_count,
457 	};
458 
459 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
460 		return;
461 
462 	ohci_notice(ohci, "%d selfIDs, generation %d, local node ID %04x\n",
463 		    self_id_count, generation, ohci->node_id);
464 
465 	while (enumerator.quadlet_count > 0) {
466 		unsigned int quadlet_count;
467 		unsigned int port_index;
468 		const u32 *s;
469 		int i;
470 
471 		s = self_id_sequence_enumerator_next(&enumerator, &quadlet_count);
472 		if (IS_ERR(s))
473 			break;
474 
475 		ohci_notice(ohci,
476 		    "selfID 0: %08x, phy %d [%c%c%c] %s gc=%d %s %s%s%s\n",
477 		    *s,
478 		    phy_packet_self_id_get_phy_id(*s),
479 		    port[self_id_sequence_get_port_status(s, quadlet_count, 0)],
480 		    port[self_id_sequence_get_port_status(s, quadlet_count, 1)],
481 		    port[self_id_sequence_get_port_status(s, quadlet_count, 2)],
482 		    speed[*s >> 14 & 3], *s >> 16 & 63,
483 		    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
484 		    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
485 
486 		port_index = 3;
487 		for (i = 1; i < quadlet_count; ++i) {
488 			ohci_notice(ohci,
489 			    "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
490 			    s[i],
491 			    phy_packet_self_id_get_phy_id(s[i]),
492 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index)],
493 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index + 1)],
494 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index + 2)],
495 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index + 3)],
496 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index + 4)],
497 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index + 5)],
498 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index + 6)],
499 			    port[self_id_sequence_get_port_status(s, quadlet_count, port_index + 7)]
500 			);
501 
502 			port_index += 8;
503 		}
504 	}
505 }
506 
507 static const char *evts[] = {
508 	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
509 	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
510 	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
511 	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
512 	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
513 	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
514 	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
515 	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
516 	[0x10] = "-reserved-",		[0x11] = "ack_complete",
517 	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
518 	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
519 	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
520 	[0x18] = "-reserved-",		[0x19] = "-reserved-",
521 	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
522 	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
523 	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
524 	[0x20] = "pending/cancelled",
525 };
526 
527 static void log_ar_at_event(struct fw_ohci *ohci,
528 			    char dir, int speed, u32 *header, int evt)
529 {
530 	static const char *const tcodes[] = {
531 		[TCODE_WRITE_QUADLET_REQUEST]	= "QW req",
532 		[TCODE_WRITE_BLOCK_REQUEST]	= "BW req",
533 		[TCODE_WRITE_RESPONSE]		= "W resp",
534 		[0x3]				= "-reserved-",
535 		[TCODE_READ_QUADLET_REQUEST]	= "QR req",
536 		[TCODE_READ_BLOCK_REQUEST]	= "BR req",
537 		[TCODE_READ_QUADLET_RESPONSE]	= "QR resp",
538 		[TCODE_READ_BLOCK_RESPONSE]	= "BR resp",
539 		[TCODE_CYCLE_START]		= "cycle start",
540 		[TCODE_LOCK_REQUEST]		= "Lk req",
541 		[TCODE_STREAM_DATA]		= "async stream packet",
542 		[TCODE_LOCK_RESPONSE]		= "Lk resp",
543 		[0xc]				= "-reserved-",
544 		[0xd]				= "-reserved-",
545 		[TCODE_LINK_INTERNAL]		= "link internal",
546 		[0xf]				= "-reserved-",
547 	};
548 	int tcode = async_header_get_tcode(header);
549 	char specific[12];
550 
551 	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
552 		return;
553 
554 	if (unlikely(evt >= ARRAY_SIZE(evts)))
555 		evt = 0x1f;
556 
557 	if (evt == OHCI1394_evt_bus_reset) {
558 		ohci_notice(ohci, "A%c evt_bus_reset, generation %d\n",
559 			    dir, (header[2] >> 16) & 0xff);
560 		return;
561 	}
562 
563 	switch (tcode) {
564 	case TCODE_WRITE_QUADLET_REQUEST:
565 	case TCODE_READ_QUADLET_RESPONSE:
566 	case TCODE_CYCLE_START:
567 		snprintf(specific, sizeof(specific), " = %08x",
568 			 be32_to_cpu((__force __be32)header[3]));
569 		break;
570 	case TCODE_WRITE_BLOCK_REQUEST:
571 	case TCODE_READ_BLOCK_REQUEST:
572 	case TCODE_READ_BLOCK_RESPONSE:
573 	case TCODE_LOCK_REQUEST:
574 	case TCODE_LOCK_RESPONSE:
575 		snprintf(specific, sizeof(specific), " %x,%x",
576 			 async_header_get_data_length(header),
577 			 async_header_get_extended_tcode(header));
578 		break;
579 	default:
580 		specific[0] = '\0';
581 	}
582 
583 	switch (tcode) {
584 	case TCODE_STREAM_DATA:
585 		ohci_notice(ohci, "A%c %s, %s\n",
586 			    dir, evts[evt], tcodes[tcode]);
587 		break;
588 	case TCODE_LINK_INTERNAL:
589 		ohci_notice(ohci, "A%c %s, PHY %08x %08x\n",
590 			    dir, evts[evt], header[1], header[2]);
591 		break;
592 	case TCODE_WRITE_QUADLET_REQUEST:
593 	case TCODE_WRITE_BLOCK_REQUEST:
594 	case TCODE_READ_QUADLET_REQUEST:
595 	case TCODE_READ_BLOCK_REQUEST:
596 	case TCODE_LOCK_REQUEST:
597 		ohci_notice(ohci,
598 			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s, %012llx%s\n",
599 			    dir, speed, async_header_get_tlabel(header),
600 			    async_header_get_source(header), async_header_get_destination(header),
601 			    evts[evt], tcodes[tcode], async_header_get_offset(header), specific);
602 		break;
603 	default:
604 		ohci_notice(ohci,
605 			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s%s\n",
606 			    dir, speed, async_header_get_tlabel(header),
607 			    async_header_get_source(header), async_header_get_destination(header),
608 			    evts[evt], tcodes[tcode], specific);
609 	}
610 }
611 
612 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
613 {
614 	writel(data, ohci->registers + offset);
615 }
616 
617 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
618 {
619 	return readl(ohci->registers + offset);
620 }
621 
622 static inline void flush_writes(const struct fw_ohci *ohci)
623 {
624 	/* Do a dummy read to flush writes. */
625 	reg_read(ohci, OHCI1394_Version);
626 }
627 
628 /*
629  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
630  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
631  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
632  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
633  */
634 static int read_phy_reg(struct fw_ohci *ohci, int addr)
635 {
636 	u32 val;
637 	int i;
638 
639 	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
640 	for (i = 0; i < 3 + 100; i++) {
641 		val = reg_read(ohci, OHCI1394_PhyControl);
642 		if (!~val)
643 			return -ENODEV; /* Card was ejected. */
644 
645 		if (val & OHCI1394_PhyControl_ReadDone)
646 			return OHCI1394_PhyControl_ReadData(val);
647 
648 		/*
649 		 * Try a few times without waiting.  Sleeping is necessary
650 		 * only when the link/PHY interface is busy.
651 		 */
652 		if (i >= 3)
653 			msleep(1);
654 	}
655 	ohci_err(ohci, "failed to read phy reg %d\n", addr);
656 	dump_stack();
657 
658 	return -EBUSY;
659 }
660 
661 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
662 {
663 	int i;
664 
665 	reg_write(ohci, OHCI1394_PhyControl,
666 		  OHCI1394_PhyControl_Write(addr, val));
667 	for (i = 0; i < 3 + 100; i++) {
668 		val = reg_read(ohci, OHCI1394_PhyControl);
669 		if (!~val)
670 			return -ENODEV; /* Card was ejected. */
671 
672 		if (!(val & OHCI1394_PhyControl_WritePending))
673 			return 0;
674 
675 		if (i >= 3)
676 			msleep(1);
677 	}
678 	ohci_err(ohci, "failed to write phy reg %d, val %u\n", addr, val);
679 	dump_stack();
680 
681 	return -EBUSY;
682 }
683 
684 static int update_phy_reg(struct fw_ohci *ohci, int addr,
685 			  int clear_bits, int set_bits)
686 {
687 	int ret = read_phy_reg(ohci, addr);
688 	if (ret < 0)
689 		return ret;
690 
691 	/*
692 	 * The interrupt status bits are cleared by writing a one bit.
693 	 * Avoid clearing them unless explicitly requested in set_bits.
694 	 */
695 	if (addr == 5)
696 		clear_bits |= PHY_INT_STATUS_BITS;
697 
698 	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
699 }
700 
701 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
702 {
703 	int ret;
704 
705 	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
706 	if (ret < 0)
707 		return ret;
708 
709 	return read_phy_reg(ohci, addr);
710 }
711 
712 static int ohci_read_phy_reg(struct fw_card *card, int addr)
713 {
714 	struct fw_ohci *ohci = fw_ohci(card);
715 
716 	guard(mutex)(&ohci->phy_reg_mutex);
717 
718 	return read_phy_reg(ohci, addr);
719 }
720 
721 static int ohci_update_phy_reg(struct fw_card *card, int addr,
722 			       int clear_bits, int set_bits)
723 {
724 	struct fw_ohci *ohci = fw_ohci(card);
725 
726 	guard(mutex)(&ohci->phy_reg_mutex);
727 
728 	return update_phy_reg(ohci, addr, clear_bits, set_bits);
729 }
730 
731 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
732 {
733 	return page_private(ctx->pages[i]);
734 }
735 
736 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
737 {
738 	struct descriptor *d;
739 
740 	d = &ctx->descriptors[index];
741 	d->branch_address  &= cpu_to_le32(~0xf);
742 	d->res_count       =  cpu_to_le16(PAGE_SIZE);
743 	d->transfer_status =  0;
744 
745 	wmb(); /* finish init of new descriptors before branch_address update */
746 	d = &ctx->descriptors[ctx->last_buffer_index];
747 	d->branch_address  |= cpu_to_le32(1);
748 
749 	ctx->last_buffer_index = index;
750 
751 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
752 }
753 
754 static void ar_context_release(struct ar_context *ctx)
755 {
756 	struct device *dev = ctx->ohci->card.device;
757 	unsigned int i;
758 
759 	if (!ctx->buffer)
760 		return;
761 
762 	vunmap(ctx->buffer);
763 
764 	for (i = 0; i < AR_BUFFERS; i++) {
765 		if (ctx->pages[i])
766 			dma_free_pages(dev, PAGE_SIZE, ctx->pages[i],
767 				       ar_buffer_bus(ctx, i), DMA_FROM_DEVICE);
768 	}
769 }
770 
771 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
772 {
773 	struct fw_ohci *ohci = ctx->ohci;
774 
775 	if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
776 		reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
777 		flush_writes(ohci);
778 
779 		ohci_err(ohci, "AR error: %s; DMA stopped\n", error_msg);
780 	}
781 	/* FIXME: restart? */
782 }
783 
784 static inline unsigned int ar_next_buffer_index(unsigned int index)
785 {
786 	return (index + 1) % AR_BUFFERS;
787 }
788 
789 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
790 {
791 	return ar_next_buffer_index(ctx->last_buffer_index);
792 }
793 
794 /*
795  * We search for the buffer that contains the last AR packet DMA data written
796  * by the controller.
797  */
798 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
799 						 unsigned int *buffer_offset)
800 {
801 	unsigned int i, next_i, last = ctx->last_buffer_index;
802 	__le16 res_count, next_res_count;
803 
804 	i = ar_first_buffer_index(ctx);
805 	res_count = READ_ONCE(ctx->descriptors[i].res_count);
806 
807 	/* A buffer that is not yet completely filled must be the last one. */
808 	while (i != last && res_count == 0) {
809 
810 		/* Peek at the next descriptor. */
811 		next_i = ar_next_buffer_index(i);
812 		rmb(); /* read descriptors in order */
813 		next_res_count = READ_ONCE(ctx->descriptors[next_i].res_count);
814 		/*
815 		 * If the next descriptor is still empty, we must stop at this
816 		 * descriptor.
817 		 */
818 		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
819 			/*
820 			 * The exception is when the DMA data for one packet is
821 			 * split over three buffers; in this case, the middle
822 			 * buffer's descriptor might be never updated by the
823 			 * controller and look still empty, and we have to peek
824 			 * at the third one.
825 			 */
826 			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
827 				next_i = ar_next_buffer_index(next_i);
828 				rmb();
829 				next_res_count = READ_ONCE(ctx->descriptors[next_i].res_count);
830 				if (next_res_count != cpu_to_le16(PAGE_SIZE))
831 					goto next_buffer_is_active;
832 			}
833 
834 			break;
835 		}
836 
837 next_buffer_is_active:
838 		i = next_i;
839 		res_count = next_res_count;
840 	}
841 
842 	rmb(); /* read res_count before the DMA data */
843 
844 	*buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
845 	if (*buffer_offset > PAGE_SIZE) {
846 		*buffer_offset = 0;
847 		ar_context_abort(ctx, "corrupted descriptor");
848 	}
849 
850 	return i;
851 }
852 
853 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
854 				    unsigned int end_buffer_index,
855 				    unsigned int end_buffer_offset)
856 {
857 	unsigned int i;
858 
859 	i = ar_first_buffer_index(ctx);
860 	while (i != end_buffer_index) {
861 		dma_sync_single_for_cpu(ctx->ohci->card.device,
862 					ar_buffer_bus(ctx, i),
863 					PAGE_SIZE, DMA_FROM_DEVICE);
864 		i = ar_next_buffer_index(i);
865 	}
866 	if (end_buffer_offset > 0)
867 		dma_sync_single_for_cpu(ctx->ohci->card.device,
868 					ar_buffer_bus(ctx, i),
869 					end_buffer_offset, DMA_FROM_DEVICE);
870 }
871 
872 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
873 static u32 cond_le32_to_cpu(__le32 value, bool has_be_header_quirk)
874 {
875 	return has_be_header_quirk ? (__force __u32)value : le32_to_cpu(value);
876 }
877 
878 static bool has_be_header_quirk(const struct fw_ohci *ohci)
879 {
880 	return !!(ohci->quirks & QUIRK_BE_HEADERS);
881 }
882 #else
883 static u32 cond_le32_to_cpu(__le32 value, bool has_be_header_quirk __maybe_unused)
884 {
885 	return le32_to_cpu(value);
886 }
887 
888 static bool has_be_header_quirk(const struct fw_ohci *ohci)
889 {
890 	return false;
891 }
892 #endif
893 
894 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
895 {
896 	struct fw_ohci *ohci = ctx->ohci;
897 	struct fw_packet p;
898 	u32 status, length, tcode;
899 	int evt;
900 
901 	p.header[0] = cond_le32_to_cpu(buffer[0], has_be_header_quirk(ohci));
902 	p.header[1] = cond_le32_to_cpu(buffer[1], has_be_header_quirk(ohci));
903 	p.header[2] = cond_le32_to_cpu(buffer[2], has_be_header_quirk(ohci));
904 
905 	tcode = async_header_get_tcode(p.header);
906 	switch (tcode) {
907 	case TCODE_WRITE_QUADLET_REQUEST:
908 	case TCODE_READ_QUADLET_RESPONSE:
909 		p.header[3] = (__force __u32) buffer[3];
910 		p.header_length = 16;
911 		p.payload_length = 0;
912 		break;
913 
914 	case TCODE_READ_BLOCK_REQUEST :
915 		p.header[3] = cond_le32_to_cpu(buffer[3], has_be_header_quirk(ohci));
916 		p.header_length = 16;
917 		p.payload_length = 0;
918 		break;
919 
920 	case TCODE_WRITE_BLOCK_REQUEST:
921 	case TCODE_READ_BLOCK_RESPONSE:
922 	case TCODE_LOCK_REQUEST:
923 	case TCODE_LOCK_RESPONSE:
924 		p.header[3] = cond_le32_to_cpu(buffer[3], has_be_header_quirk(ohci));
925 		p.header_length = 16;
926 		p.payload_length = async_header_get_data_length(p.header);
927 		if (p.payload_length > MAX_ASYNC_PAYLOAD) {
928 			ar_context_abort(ctx, "invalid packet length");
929 			return NULL;
930 		}
931 		break;
932 
933 	case TCODE_WRITE_RESPONSE:
934 	case TCODE_READ_QUADLET_REQUEST:
935 	case TCODE_LINK_INTERNAL:
936 		p.header_length = 12;
937 		p.payload_length = 0;
938 		break;
939 
940 	default:
941 		ar_context_abort(ctx, "invalid tcode");
942 		return NULL;
943 	}
944 
945 	p.payload = (void *) buffer + p.header_length;
946 
947 	/* FIXME: What to do about evt_* errors? */
948 	length = (p.header_length + p.payload_length + 3) / 4;
949 	status = cond_le32_to_cpu(buffer[length], has_be_header_quirk(ohci));
950 	evt    = (status >> 16) & 0x1f;
951 
952 	p.ack        = evt - 16;
953 	p.speed      = (status >> 21) & 0x7;
954 	p.timestamp  = status & 0xffff;
955 	p.generation = ohci->request_generation;
956 
957 	log_ar_at_event(ohci, 'R', p.speed, p.header, evt);
958 
959 	/*
960 	 * Several controllers, notably from NEC and VIA, forget to
961 	 * write ack_complete status at PHY packet reception.
962 	 */
963 	if (evt == OHCI1394_evt_no_status && tcode == TCODE_LINK_INTERNAL)
964 		p.ack = ACK_COMPLETE;
965 
966 	/*
967 	 * The OHCI bus reset handler synthesizes a PHY packet with
968 	 * the new generation number when a bus reset happens (see
969 	 * section 8.4.2.3).  This helps us determine when a request
970 	 * was received and make sure we send the response in the same
971 	 * generation.  We only need this for requests; for responses
972 	 * we use the unique tlabel for finding the matching
973 	 * request.
974 	 *
975 	 * Alas some chips sometimes emit bus reset packets with a
976 	 * wrong generation.  We set the correct generation for these
977 	 * at a slightly incorrect time (in bus_reset_work).
978 	 */
979 	if (evt == OHCI1394_evt_bus_reset) {
980 		if (!(ohci->quirks & QUIRK_RESET_PACKET))
981 			ohci->request_generation = (p.header[2] >> 16) & 0xff;
982 	} else if (ctx == &ohci->ar_request_ctx) {
983 		fw_core_handle_request(&ohci->card, &p);
984 	} else {
985 		fw_core_handle_response(&ohci->card, &p);
986 	}
987 
988 	return buffer + length + 1;
989 }
990 
991 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
992 {
993 	void *next;
994 
995 	while (p < end) {
996 		next = handle_ar_packet(ctx, p);
997 		if (!next)
998 			return p;
999 		p = next;
1000 	}
1001 
1002 	return p;
1003 }
1004 
1005 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
1006 {
1007 	unsigned int i;
1008 
1009 	i = ar_first_buffer_index(ctx);
1010 	while (i != end_buffer) {
1011 		dma_sync_single_for_device(ctx->ohci->card.device,
1012 					   ar_buffer_bus(ctx, i),
1013 					   PAGE_SIZE, DMA_FROM_DEVICE);
1014 		ar_context_link_page(ctx, i);
1015 		i = ar_next_buffer_index(i);
1016 	}
1017 }
1018 
1019 static void ar_context_tasklet(unsigned long data)
1020 {
1021 	struct ar_context *ctx = (struct ar_context *)data;
1022 	unsigned int end_buffer_index, end_buffer_offset;
1023 	void *p, *end;
1024 
1025 	p = ctx->pointer;
1026 	if (!p)
1027 		return;
1028 
1029 	end_buffer_index = ar_search_last_active_buffer(ctx,
1030 							&end_buffer_offset);
1031 	ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
1032 	end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
1033 
1034 	if (end_buffer_index < ar_first_buffer_index(ctx)) {
1035 		/*
1036 		 * The filled part of the overall buffer wraps around; handle
1037 		 * all packets up to the buffer end here.  If the last packet
1038 		 * wraps around, its tail will be visible after the buffer end
1039 		 * because the buffer start pages are mapped there again.
1040 		 */
1041 		void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
1042 		p = handle_ar_packets(ctx, p, buffer_end);
1043 		if (p < buffer_end)
1044 			goto error;
1045 		/* adjust p to point back into the actual buffer */
1046 		p -= AR_BUFFERS * PAGE_SIZE;
1047 	}
1048 
1049 	p = handle_ar_packets(ctx, p, end);
1050 	if (p != end) {
1051 		if (p > end)
1052 			ar_context_abort(ctx, "inconsistent descriptor");
1053 		goto error;
1054 	}
1055 
1056 	ctx->pointer = p;
1057 	ar_recycle_buffers(ctx, end_buffer_index);
1058 
1059 	return;
1060 
1061 error:
1062 	ctx->pointer = NULL;
1063 }
1064 
1065 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
1066 			   unsigned int descriptors_offset, u32 regs)
1067 {
1068 	struct device *dev = ohci->card.device;
1069 	unsigned int i;
1070 	dma_addr_t dma_addr;
1071 	struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
1072 	struct descriptor *d;
1073 
1074 	ctx->regs        = regs;
1075 	ctx->ohci        = ohci;
1076 	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
1077 
1078 	for (i = 0; i < AR_BUFFERS; i++) {
1079 		ctx->pages[i] = dma_alloc_pages(dev, PAGE_SIZE, &dma_addr,
1080 						DMA_FROM_DEVICE, GFP_KERNEL);
1081 		if (!ctx->pages[i])
1082 			goto out_of_memory;
1083 		set_page_private(ctx->pages[i], dma_addr);
1084 		dma_sync_single_for_device(dev, dma_addr, PAGE_SIZE,
1085 					   DMA_FROM_DEVICE);
1086 	}
1087 
1088 	for (i = 0; i < AR_BUFFERS; i++)
1089 		pages[i]              = ctx->pages[i];
1090 	for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
1091 		pages[AR_BUFFERS + i] = ctx->pages[i];
1092 	ctx->buffer = vmap(pages, ARRAY_SIZE(pages), VM_MAP, PAGE_KERNEL);
1093 	if (!ctx->buffer)
1094 		goto out_of_memory;
1095 
1096 	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
1097 	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
1098 
1099 	for (i = 0; i < AR_BUFFERS; i++) {
1100 		d = &ctx->descriptors[i];
1101 		d->req_count      = cpu_to_le16(PAGE_SIZE);
1102 		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
1103 						DESCRIPTOR_STATUS |
1104 						DESCRIPTOR_BRANCH_ALWAYS);
1105 		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
1106 		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
1107 			ar_next_buffer_index(i) * sizeof(struct descriptor));
1108 	}
1109 
1110 	return 0;
1111 
1112 out_of_memory:
1113 	ar_context_release(ctx);
1114 
1115 	return -ENOMEM;
1116 }
1117 
1118 static void ar_context_run(struct ar_context *ctx)
1119 {
1120 	unsigned int i;
1121 
1122 	for (i = 0; i < AR_BUFFERS; i++)
1123 		ar_context_link_page(ctx, i);
1124 
1125 	ctx->pointer = ctx->buffer;
1126 
1127 	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1128 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1129 }
1130 
1131 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1132 {
1133 	__le16 branch;
1134 
1135 	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1136 
1137 	/* figure out which descriptor the branch address goes in */
1138 	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1139 		return d;
1140 	else
1141 		return d + z - 1;
1142 }
1143 
1144 static void context_tasklet(unsigned long data)
1145 {
1146 	struct context *ctx = (struct context *) data;
1147 	struct descriptor *d, *last;
1148 	u32 address;
1149 	int z;
1150 	struct descriptor_buffer *desc;
1151 
1152 	desc = list_entry(ctx->buffer_list.next,
1153 			struct descriptor_buffer, list);
1154 	last = ctx->last;
1155 	while (last->branch_address != 0) {
1156 		struct descriptor_buffer *old_desc = desc;
1157 		address = le32_to_cpu(last->branch_address);
1158 		z = address & 0xf;
1159 		address &= ~0xf;
1160 		ctx->current_bus = address;
1161 
1162 		/* If the branch address points to a buffer outside of the
1163 		 * current buffer, advance to the next buffer. */
1164 		if (address < desc->buffer_bus ||
1165 				address >= desc->buffer_bus + desc->used)
1166 			desc = list_entry(desc->list.next,
1167 					struct descriptor_buffer, list);
1168 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1169 		last = find_branch_descriptor(d, z);
1170 
1171 		if (!ctx->callback(ctx, d, last))
1172 			break;
1173 
1174 		if (old_desc != desc) {
1175 			// If we've advanced to the next buffer, move the previous buffer to the
1176 			// free list.
1177 			old_desc->used = 0;
1178 			guard(spinlock_irqsave)(&ctx->ohci->lock);
1179 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1180 		}
1181 		ctx->last = last;
1182 	}
1183 }
1184 
1185 static void ohci_isoc_context_work(struct work_struct *work)
1186 {
1187 	struct fw_iso_context *base = container_of(work, struct fw_iso_context, work);
1188 	struct iso_context *isoc_ctx = container_of(base, struct iso_context, base);
1189 	struct context *ctx = &isoc_ctx->context;
1190 	struct descriptor *d, *last;
1191 	u32 address;
1192 	int z;
1193 	struct descriptor_buffer *desc;
1194 
1195 	desc = list_entry(ctx->buffer_list.next, struct descriptor_buffer, list);
1196 	last = ctx->last;
1197 	while (last->branch_address != 0) {
1198 		struct descriptor_buffer *old_desc = desc;
1199 
1200 		address = le32_to_cpu(last->branch_address);
1201 		z = address & 0xf;
1202 		address &= ~0xf;
1203 		ctx->current_bus = address;
1204 
1205 		// If the branch address points to a buffer outside of the current buffer, advance
1206 		// to the next buffer.
1207 		if (address < desc->buffer_bus || address >= desc->buffer_bus + desc->used)
1208 			desc = list_entry(desc->list.next, struct descriptor_buffer, list);
1209 		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1210 		last = find_branch_descriptor(d, z);
1211 
1212 		if (!ctx->callback(ctx, d, last))
1213 			break;
1214 
1215 		if (old_desc != desc) {
1216 			// If we've advanced to the next buffer, move the previous buffer to the
1217 			// free list.
1218 			old_desc->used = 0;
1219 			guard(spinlock_irqsave)(&ctx->ohci->lock);
1220 			list_move_tail(&old_desc->list, &ctx->buffer_list);
1221 		}
1222 		ctx->last = last;
1223 	}
1224 }
1225 
1226 /*
1227  * Allocate a new buffer and add it to the list of free buffers for this
1228  * context.  Must be called with ohci->lock held.
1229  */
1230 static int context_add_buffer(struct context *ctx)
1231 {
1232 	struct descriptor_buffer *desc;
1233 	dma_addr_t bus_addr;
1234 	int offset;
1235 
1236 	/*
1237 	 * 16MB of descriptors should be far more than enough for any DMA
1238 	 * program.  This will catch run-away userspace or DoS attacks.
1239 	 */
1240 	if (ctx->total_allocation >= 16*1024*1024)
1241 		return -ENOMEM;
1242 
1243 	desc = dmam_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE, &bus_addr, GFP_ATOMIC);
1244 	if (!desc)
1245 		return -ENOMEM;
1246 
1247 	offset = (void *)&desc->buffer - (void *)desc;
1248 	/*
1249 	 * Some controllers, like JMicron ones, always issue 0x20-byte DMA reads
1250 	 * for descriptors, even 0x10-byte ones. This can cause page faults when
1251 	 * an IOMMU is in use and the oversized read crosses a page boundary.
1252 	 * Work around this by always leaving at least 0x10 bytes of padding.
1253 	 */
1254 	desc->buffer_size = PAGE_SIZE - offset - 0x10;
1255 	desc->buffer_bus = bus_addr + offset;
1256 	desc->used = 0;
1257 
1258 	list_add_tail(&desc->list, &ctx->buffer_list);
1259 	ctx->total_allocation += PAGE_SIZE;
1260 
1261 	return 0;
1262 }
1263 
1264 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1265 			u32 regs, descriptor_callback_t callback)
1266 {
1267 	ctx->ohci = ohci;
1268 	ctx->regs = regs;
1269 	ctx->total_allocation = 0;
1270 
1271 	INIT_LIST_HEAD(&ctx->buffer_list);
1272 	if (context_add_buffer(ctx) < 0)
1273 		return -ENOMEM;
1274 
1275 	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1276 			struct descriptor_buffer, list);
1277 
1278 	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1279 	ctx->callback = callback;
1280 
1281 	/*
1282 	 * We put a dummy descriptor in the buffer that has a NULL
1283 	 * branch address and looks like it's been sent.  That way we
1284 	 * have a descriptor to append DMA programs to.
1285 	 */
1286 	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1287 	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1288 	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1289 	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1290 	ctx->last = ctx->buffer_tail->buffer;
1291 	ctx->prev = ctx->buffer_tail->buffer;
1292 	ctx->prev_z = 1;
1293 
1294 	return 0;
1295 }
1296 
1297 static void context_release(struct context *ctx)
1298 {
1299 	struct fw_card *card = &ctx->ohci->card;
1300 	struct descriptor_buffer *desc, *tmp;
1301 
1302 	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list) {
1303 		dmam_free_coherent(card->device, PAGE_SIZE, desc,
1304 				   desc->buffer_bus - ((void *)&desc->buffer - (void *)desc));
1305 	}
1306 }
1307 
1308 /* Must be called with ohci->lock held */
1309 static struct descriptor *context_get_descriptors(struct context *ctx,
1310 						  int z, dma_addr_t *d_bus)
1311 {
1312 	struct descriptor *d = NULL;
1313 	struct descriptor_buffer *desc = ctx->buffer_tail;
1314 
1315 	if (z * sizeof(*d) > desc->buffer_size)
1316 		return NULL;
1317 
1318 	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1319 		/* No room for the descriptor in this buffer, so advance to the
1320 		 * next one. */
1321 
1322 		if (desc->list.next == &ctx->buffer_list) {
1323 			/* If there is no free buffer next in the list,
1324 			 * allocate one. */
1325 			if (context_add_buffer(ctx) < 0)
1326 				return NULL;
1327 		}
1328 		desc = list_entry(desc->list.next,
1329 				struct descriptor_buffer, list);
1330 		ctx->buffer_tail = desc;
1331 	}
1332 
1333 	d = desc->buffer + desc->used / sizeof(*d);
1334 	memset(d, 0, z * sizeof(*d));
1335 	*d_bus = desc->buffer_bus + desc->used;
1336 
1337 	return d;
1338 }
1339 
1340 static void context_run(struct context *ctx, u32 extra)
1341 {
1342 	struct fw_ohci *ohci = ctx->ohci;
1343 
1344 	reg_write(ohci, COMMAND_PTR(ctx->regs),
1345 		  le32_to_cpu(ctx->last->branch_address));
1346 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1347 	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1348 	ctx->running = true;
1349 	flush_writes(ohci);
1350 }
1351 
1352 static void context_append(struct context *ctx,
1353 			   struct descriptor *d, int z, int extra)
1354 {
1355 	dma_addr_t d_bus;
1356 	struct descriptor_buffer *desc = ctx->buffer_tail;
1357 	struct descriptor *d_branch;
1358 
1359 	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1360 
1361 	desc->used += (z + extra) * sizeof(*d);
1362 
1363 	wmb(); /* finish init of new descriptors before branch_address update */
1364 
1365 	d_branch = find_branch_descriptor(ctx->prev, ctx->prev_z);
1366 	d_branch->branch_address = cpu_to_le32(d_bus | z);
1367 
1368 	/*
1369 	 * VT6306 incorrectly checks only the single descriptor at the
1370 	 * CommandPtr when the wake bit is written, so if it's a
1371 	 * multi-descriptor block starting with an INPUT_MORE, put a copy of
1372 	 * the branch address in the first descriptor.
1373 	 *
1374 	 * Not doing this for transmit contexts since not sure how it interacts
1375 	 * with skip addresses.
1376 	 */
1377 	if (unlikely(ctx->ohci->quirks & QUIRK_IR_WAKE) &&
1378 	    d_branch != ctx->prev &&
1379 	    (ctx->prev->control & cpu_to_le16(DESCRIPTOR_CMD)) ==
1380 	     cpu_to_le16(DESCRIPTOR_INPUT_MORE)) {
1381 		ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1382 	}
1383 
1384 	ctx->prev = d;
1385 	ctx->prev_z = z;
1386 }
1387 
1388 static void context_stop(struct context *ctx)
1389 {
1390 	struct fw_ohci *ohci = ctx->ohci;
1391 	u32 reg;
1392 	int i;
1393 
1394 	reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1395 	ctx->running = false;
1396 
1397 	for (i = 0; i < 1000; i++) {
1398 		reg = reg_read(ohci, CONTROL_SET(ctx->regs));
1399 		if ((reg & CONTEXT_ACTIVE) == 0)
1400 			return;
1401 
1402 		if (i)
1403 			udelay(10);
1404 	}
1405 	ohci_err(ohci, "DMA context still active (0x%08x)\n", reg);
1406 }
1407 
1408 struct driver_data {
1409 	u8 inline_data[8];
1410 	struct fw_packet *packet;
1411 };
1412 
1413 /*
1414  * This function apppends a packet to the DMA queue for transmission.
1415  * Must always be called with the ochi->lock held to ensure proper
1416  * generation handling and locking around packet queue manipulation.
1417  */
1418 static int at_context_queue_packet(struct context *ctx,
1419 				   struct fw_packet *packet)
1420 {
1421 	struct fw_ohci *ohci = ctx->ohci;
1422 	dma_addr_t d_bus, payload_bus;
1423 	struct driver_data *driver_data;
1424 	struct descriptor *d, *last;
1425 	__le32 *header;
1426 	int z, tcode;
1427 
1428 	d = context_get_descriptors(ctx, 4, &d_bus);
1429 	if (d == NULL) {
1430 		packet->ack = RCODE_SEND_ERROR;
1431 		return -1;
1432 	}
1433 
1434 	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1435 	d[0].res_count = cpu_to_le16(packet->timestamp);
1436 
1437 	tcode = async_header_get_tcode(packet->header);
1438 	header = (__le32 *) &d[1];
1439 	switch (tcode) {
1440 	case TCODE_WRITE_QUADLET_REQUEST:
1441 	case TCODE_WRITE_BLOCK_REQUEST:
1442 	case TCODE_WRITE_RESPONSE:
1443 	case TCODE_READ_QUADLET_REQUEST:
1444 	case TCODE_READ_BLOCK_REQUEST:
1445 	case TCODE_READ_QUADLET_RESPONSE:
1446 	case TCODE_READ_BLOCK_RESPONSE:
1447 	case TCODE_LOCK_REQUEST:
1448 	case TCODE_LOCK_RESPONSE:
1449 		ohci1394_at_data_set_src_bus_id(header, false);
1450 		ohci1394_at_data_set_speed(header, packet->speed);
1451 		ohci1394_at_data_set_tlabel(header, async_header_get_tlabel(packet->header));
1452 		ohci1394_at_data_set_retry(header, async_header_get_retry(packet->header));
1453 		ohci1394_at_data_set_tcode(header, tcode);
1454 
1455 		ohci1394_at_data_set_destination_id(header,
1456 						    async_header_get_destination(packet->header));
1457 
1458 		if (ctx == &ctx->ohci->at_response_ctx) {
1459 			ohci1394_at_data_set_rcode(header, async_header_get_rcode(packet->header));
1460 		} else {
1461 			ohci1394_at_data_set_destination_offset(header,
1462 							async_header_get_offset(packet->header));
1463 		}
1464 
1465 		if (tcode_is_block_packet(tcode))
1466 			header[3] = cpu_to_le32(packet->header[3]);
1467 		else
1468 			header[3] = (__force __le32) packet->header[3];
1469 
1470 		d[0].req_count = cpu_to_le16(packet->header_length);
1471 		break;
1472 	case TCODE_LINK_INTERNAL:
1473 		ohci1394_at_data_set_speed(header, packet->speed);
1474 		ohci1394_at_data_set_tcode(header, TCODE_LINK_INTERNAL);
1475 
1476 		header[1] = cpu_to_le32(packet->header[1]);
1477 		header[2] = cpu_to_le32(packet->header[2]);
1478 		d[0].req_count = cpu_to_le16(12);
1479 
1480 		if (is_ping_packet(&packet->header[1]))
1481 			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1482 		break;
1483 
1484 	case TCODE_STREAM_DATA:
1485 		ohci1394_it_data_set_speed(header, packet->speed);
1486 		ohci1394_it_data_set_tag(header, isoc_header_get_tag(packet->header[0]));
1487 		ohci1394_it_data_set_channel(header, isoc_header_get_channel(packet->header[0]));
1488 		ohci1394_it_data_set_tcode(header, TCODE_STREAM_DATA);
1489 		ohci1394_it_data_set_sync(header, isoc_header_get_sy(packet->header[0]));
1490 
1491 		ohci1394_it_data_set_data_length(header, isoc_header_get_data_length(packet->header[0]));
1492 
1493 		d[0].req_count = cpu_to_le16(8);
1494 		break;
1495 
1496 	default:
1497 		/* BUG(); */
1498 		packet->ack = RCODE_SEND_ERROR;
1499 		return -1;
1500 	}
1501 
1502 	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1503 	driver_data = (struct driver_data *) &d[3];
1504 	driver_data->packet = packet;
1505 	packet->driver_data = driver_data;
1506 
1507 	if (packet->payload_length > 0) {
1508 		if (packet->payload_length > sizeof(driver_data->inline_data)) {
1509 			payload_bus = dma_map_single(ohci->card.device,
1510 						     packet->payload,
1511 						     packet->payload_length,
1512 						     DMA_TO_DEVICE);
1513 			if (dma_mapping_error(ohci->card.device, payload_bus)) {
1514 				packet->ack = RCODE_SEND_ERROR;
1515 				return -1;
1516 			}
1517 			packet->payload_bus	= payload_bus;
1518 			packet->payload_mapped	= true;
1519 		} else {
1520 			memcpy(driver_data->inline_data, packet->payload,
1521 			       packet->payload_length);
1522 			payload_bus = d_bus + 3 * sizeof(*d);
1523 		}
1524 
1525 		d[2].req_count    = cpu_to_le16(packet->payload_length);
1526 		d[2].data_address = cpu_to_le32(payload_bus);
1527 		last = &d[2];
1528 		z = 3;
1529 	} else {
1530 		last = &d[0];
1531 		z = 2;
1532 	}
1533 
1534 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1535 				     DESCRIPTOR_IRQ_ALWAYS |
1536 				     DESCRIPTOR_BRANCH_ALWAYS);
1537 
1538 	/* FIXME: Document how the locking works. */
1539 	if (ohci->generation != packet->generation) {
1540 		if (packet->payload_mapped)
1541 			dma_unmap_single(ohci->card.device, payload_bus,
1542 					 packet->payload_length, DMA_TO_DEVICE);
1543 		packet->ack = RCODE_GENERATION;
1544 		return -1;
1545 	}
1546 
1547 	context_append(ctx, d, z, 4 - z);
1548 
1549 	if (ctx->running)
1550 		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1551 	else
1552 		context_run(ctx, 0);
1553 
1554 	return 0;
1555 }
1556 
1557 static void at_context_flush(struct context *ctx)
1558 {
1559 	tasklet_disable(&ctx->tasklet);
1560 
1561 	ctx->flushing = true;
1562 	context_tasklet((unsigned long)ctx);
1563 	ctx->flushing = false;
1564 
1565 	tasklet_enable(&ctx->tasklet);
1566 }
1567 
1568 static int handle_at_packet(struct context *context,
1569 			    struct descriptor *d,
1570 			    struct descriptor *last)
1571 {
1572 	struct driver_data *driver_data;
1573 	struct fw_packet *packet;
1574 	struct fw_ohci *ohci = context->ohci;
1575 	int evt;
1576 
1577 	if (last->transfer_status == 0 && !context->flushing)
1578 		/* This descriptor isn't done yet, stop iteration. */
1579 		return 0;
1580 
1581 	driver_data = (struct driver_data *) &d[3];
1582 	packet = driver_data->packet;
1583 	if (packet == NULL)
1584 		/* This packet was cancelled, just continue. */
1585 		return 1;
1586 
1587 	if (packet->payload_mapped)
1588 		dma_unmap_single(ohci->card.device, packet->payload_bus,
1589 				 packet->payload_length, DMA_TO_DEVICE);
1590 
1591 	evt = le16_to_cpu(last->transfer_status) & 0x1f;
1592 	packet->timestamp = le16_to_cpu(last->res_count);
1593 
1594 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);
1595 
1596 	switch (evt) {
1597 	case OHCI1394_evt_timeout:
1598 		/* Async response transmit timed out. */
1599 		packet->ack = RCODE_CANCELLED;
1600 		break;
1601 
1602 	case OHCI1394_evt_flushed:
1603 		/*
1604 		 * The packet was flushed should give same error as
1605 		 * when we try to use a stale generation count.
1606 		 */
1607 		packet->ack = RCODE_GENERATION;
1608 		break;
1609 
1610 	case OHCI1394_evt_missing_ack:
1611 		if (context->flushing)
1612 			packet->ack = RCODE_GENERATION;
1613 		else {
1614 			/*
1615 			 * Using a valid (current) generation count, but the
1616 			 * node is not on the bus or not sending acks.
1617 			 */
1618 			packet->ack = RCODE_NO_ACK;
1619 		}
1620 		break;
1621 
1622 	case ACK_COMPLETE + 0x10:
1623 	case ACK_PENDING + 0x10:
1624 	case ACK_BUSY_X + 0x10:
1625 	case ACK_BUSY_A + 0x10:
1626 	case ACK_BUSY_B + 0x10:
1627 	case ACK_DATA_ERROR + 0x10:
1628 	case ACK_TYPE_ERROR + 0x10:
1629 		packet->ack = evt - 0x10;
1630 		break;
1631 
1632 	case OHCI1394_evt_no_status:
1633 		if (context->flushing) {
1634 			packet->ack = RCODE_GENERATION;
1635 			break;
1636 		}
1637 		fallthrough;
1638 
1639 	default:
1640 		packet->ack = RCODE_SEND_ERROR;
1641 		break;
1642 	}
1643 
1644 	packet->callback(packet, &ohci->card, packet->ack);
1645 
1646 	return 1;
1647 }
1648 
1649 static u32 get_cycle_time(struct fw_ohci *ohci);
1650 
1651 static void handle_local_rom(struct fw_ohci *ohci,
1652 			     struct fw_packet *packet, u32 csr)
1653 {
1654 	struct fw_packet response;
1655 	int tcode, length, i;
1656 
1657 	tcode = async_header_get_tcode(packet->header);
1658 	if (tcode_is_block_packet(tcode))
1659 		length = async_header_get_data_length(packet->header);
1660 	else
1661 		length = 4;
1662 
1663 	i = csr - CSR_CONFIG_ROM;
1664 	if (i + length > CONFIG_ROM_SIZE) {
1665 		fw_fill_response(&response, packet->header,
1666 				 RCODE_ADDRESS_ERROR, NULL, 0);
1667 	} else if (!tcode_is_read_request(tcode)) {
1668 		fw_fill_response(&response, packet->header,
1669 				 RCODE_TYPE_ERROR, NULL, 0);
1670 	} else {
1671 		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1672 				 (void *) ohci->config_rom + i, length);
1673 	}
1674 
1675 	// Timestamping on behalf of the hardware.
1676 	response.timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ohci));
1677 	fw_core_handle_response(&ohci->card, &response);
1678 }
1679 
1680 static void handle_local_lock(struct fw_ohci *ohci,
1681 			      struct fw_packet *packet, u32 csr)
1682 {
1683 	struct fw_packet response;
1684 	int tcode, length, ext_tcode, sel, try;
1685 	__be32 *payload, lock_old;
1686 	u32 lock_arg, lock_data;
1687 
1688 	tcode = async_header_get_tcode(packet->header);
1689 	length = async_header_get_data_length(packet->header);
1690 	payload = packet->payload;
1691 	ext_tcode = async_header_get_extended_tcode(packet->header);
1692 
1693 	if (tcode == TCODE_LOCK_REQUEST &&
1694 	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1695 		lock_arg = be32_to_cpu(payload[0]);
1696 		lock_data = be32_to_cpu(payload[1]);
1697 	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1698 		lock_arg = 0;
1699 		lock_data = 0;
1700 	} else {
1701 		fw_fill_response(&response, packet->header,
1702 				 RCODE_TYPE_ERROR, NULL, 0);
1703 		goto out;
1704 	}
1705 
1706 	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1707 	reg_write(ohci, OHCI1394_CSRData, lock_data);
1708 	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1709 	reg_write(ohci, OHCI1394_CSRControl, sel);
1710 
1711 	for (try = 0; try < 20; try++)
1712 		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1713 			lock_old = cpu_to_be32(reg_read(ohci,
1714 							OHCI1394_CSRData));
1715 			fw_fill_response(&response, packet->header,
1716 					 RCODE_COMPLETE,
1717 					 &lock_old, sizeof(lock_old));
1718 			goto out;
1719 		}
1720 
1721 	ohci_err(ohci, "swap not done (CSR lock timeout)\n");
1722 	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1723 
1724  out:
1725 	// Timestamping on behalf of the hardware.
1726 	response.timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ohci));
1727 	fw_core_handle_response(&ohci->card, &response);
1728 }
1729 
1730 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1731 {
1732 	u64 offset, csr;
1733 
1734 	if (ctx == &ctx->ohci->at_request_ctx) {
1735 		packet->ack = ACK_PENDING;
1736 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1737 	}
1738 
1739 	offset = async_header_get_offset(packet->header);
1740 	csr = offset - CSR_REGISTER_BASE;
1741 
1742 	/* Handle config rom reads. */
1743 	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1744 		handle_local_rom(ctx->ohci, packet, csr);
1745 	else switch (csr) {
1746 	case CSR_BUS_MANAGER_ID:
1747 	case CSR_BANDWIDTH_AVAILABLE:
1748 	case CSR_CHANNELS_AVAILABLE_HI:
1749 	case CSR_CHANNELS_AVAILABLE_LO:
1750 		handle_local_lock(ctx->ohci, packet, csr);
1751 		break;
1752 	default:
1753 		if (ctx == &ctx->ohci->at_request_ctx)
1754 			fw_core_handle_request(&ctx->ohci->card, packet);
1755 		else
1756 			fw_core_handle_response(&ctx->ohci->card, packet);
1757 		break;
1758 	}
1759 
1760 	if (ctx == &ctx->ohci->at_response_ctx) {
1761 		packet->ack = ACK_COMPLETE;
1762 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1763 	}
1764 }
1765 
1766 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1767 {
1768 	unsigned long flags;
1769 	int ret;
1770 
1771 	spin_lock_irqsave(&ctx->ohci->lock, flags);
1772 
1773 	if (async_header_get_destination(packet->header) == ctx->ohci->node_id &&
1774 	    ctx->ohci->generation == packet->generation) {
1775 		spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1776 
1777 		// Timestamping on behalf of the hardware.
1778 		packet->timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ctx->ohci));
1779 
1780 		handle_local_request(ctx, packet);
1781 		return;
1782 	}
1783 
1784 	ret = at_context_queue_packet(ctx, packet);
1785 	spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1786 
1787 	if (ret < 0) {
1788 		// Timestamping on behalf of the hardware.
1789 		packet->timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ctx->ohci));
1790 
1791 		packet->callback(packet, &ctx->ohci->card, packet->ack);
1792 	}
1793 }
1794 
1795 static void detect_dead_context(struct fw_ohci *ohci,
1796 				const char *name, unsigned int regs)
1797 {
1798 	u32 ctl;
1799 
1800 	ctl = reg_read(ohci, CONTROL_SET(regs));
1801 	if (ctl & CONTEXT_DEAD)
1802 		ohci_err(ohci, "DMA context %s has stopped, error code: %s\n",
1803 			name, evts[ctl & 0x1f]);
1804 }
1805 
1806 static void handle_dead_contexts(struct fw_ohci *ohci)
1807 {
1808 	unsigned int i;
1809 	char name[8];
1810 
1811 	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1812 	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1813 	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1814 	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1815 	for (i = 0; i < 32; ++i) {
1816 		if (!(ohci->it_context_support & (1 << i)))
1817 			continue;
1818 		sprintf(name, "IT%u", i);
1819 		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1820 	}
1821 	for (i = 0; i < 32; ++i) {
1822 		if (!(ohci->ir_context_support & (1 << i)))
1823 			continue;
1824 		sprintf(name, "IR%u", i);
1825 		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1826 	}
1827 	/* TODO: maybe try to flush and restart the dead contexts */
1828 }
1829 
1830 static u32 cycle_timer_ticks(u32 cycle_timer)
1831 {
1832 	u32 ticks;
1833 
1834 	ticks = cycle_timer & 0xfff;
1835 	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1836 	ticks += (3072 * 8000) * (cycle_timer >> 25);
1837 
1838 	return ticks;
1839 }
1840 
1841 /*
1842  * Some controllers exhibit one or more of the following bugs when updating the
1843  * iso cycle timer register:
1844  *  - When the lowest six bits are wrapping around to zero, a read that happens
1845  *    at the same time will return garbage in the lowest ten bits.
1846  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1847  *    not incremented for about 60 ns.
1848  *  - Occasionally, the entire register reads zero.
1849  *
1850  * To catch these, we read the register three times and ensure that the
1851  * difference between each two consecutive reads is approximately the same, i.e.
1852  * less than twice the other.  Furthermore, any negative difference indicates an
1853  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1854  * execute, so we have enough precision to compute the ratio of the differences.)
1855  */
1856 static u32 get_cycle_time(struct fw_ohci *ohci)
1857 {
1858 	u32 c0, c1, c2;
1859 	u32 t0, t1, t2;
1860 	s32 diff01, diff12;
1861 	int i;
1862 
1863 	if (has_reboot_by_cycle_timer_read_quirk(ohci))
1864 		return 0;
1865 
1866 	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1867 
1868 	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1869 		i = 0;
1870 		c1 = c2;
1871 		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1872 		do {
1873 			c0 = c1;
1874 			c1 = c2;
1875 			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1876 			t0 = cycle_timer_ticks(c0);
1877 			t1 = cycle_timer_ticks(c1);
1878 			t2 = cycle_timer_ticks(c2);
1879 			diff01 = t1 - t0;
1880 			diff12 = t2 - t1;
1881 		} while ((diff01 <= 0 || diff12 <= 0 ||
1882 			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1883 			 && i++ < 20);
1884 	}
1885 
1886 	return c2;
1887 }
1888 
1889 /*
1890  * This function has to be called at least every 64 seconds.  The bus_time
1891  * field stores not only the upper 25 bits of the BUS_TIME register but also
1892  * the most significant bit of the cycle timer in bit 6 so that we can detect
1893  * changes in this bit.
1894  */
1895 static u32 update_bus_time(struct fw_ohci *ohci)
1896 {
1897 	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1898 
1899 	if (unlikely(!ohci->bus_time_running)) {
1900 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_cycle64Seconds);
1901 		ohci->bus_time = (lower_32_bits(ktime_get_seconds()) & ~0x7f) |
1902 		                 (cycle_time_seconds & 0x40);
1903 		ohci->bus_time_running = true;
1904 	}
1905 
1906 	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1907 		ohci->bus_time += 0x40;
1908 
1909 	return ohci->bus_time | cycle_time_seconds;
1910 }
1911 
1912 static int get_status_for_port(struct fw_ohci *ohci, int port_index,
1913 			       enum phy_packet_self_id_port_status *status)
1914 {
1915 	int reg;
1916 
1917 	scoped_guard(mutex, &ohci->phy_reg_mutex) {
1918 		reg = write_phy_reg(ohci, 7, port_index);
1919 		if (reg < 0)
1920 			return reg;
1921 
1922 		reg = read_phy_reg(ohci, 8);
1923 		if (reg < 0)
1924 			return reg;
1925 	}
1926 
1927 	switch (reg & 0x0f) {
1928 	case 0x06:
1929 		// is child node (connected to parent node)
1930 		*status = PHY_PACKET_SELF_ID_PORT_STATUS_PARENT;
1931 		break;
1932 	case 0x0e:
1933 		// is parent node (connected to child node)
1934 		*status = PHY_PACKET_SELF_ID_PORT_STATUS_CHILD;
1935 		break;
1936 	default:
1937 		// not connected
1938 		*status = PHY_PACKET_SELF_ID_PORT_STATUS_NCONN;
1939 		break;
1940 	}
1941 
1942 	return 0;
1943 }
1944 
1945 static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
1946 	int self_id_count)
1947 {
1948 	unsigned int left_phy_id = phy_packet_self_id_get_phy_id(self_id);
1949 	int i;
1950 
1951 	for (i = 0; i < self_id_count; i++) {
1952 		u32 entry = ohci->self_id_buffer[i];
1953 		unsigned int right_phy_id = phy_packet_self_id_get_phy_id(entry);
1954 
1955 		if (left_phy_id == right_phy_id)
1956 			return -1;
1957 		if (left_phy_id < right_phy_id)
1958 			return i;
1959 	}
1960 	return i;
1961 }
1962 
1963 static int detect_initiated_reset(struct fw_ohci *ohci, bool *is_initiated_reset)
1964 {
1965 	int reg;
1966 
1967 	guard(mutex)(&ohci->phy_reg_mutex);
1968 
1969 	// Select page 7
1970 	reg = write_phy_reg(ohci, 7, 0xe0);
1971 	if (reg < 0)
1972 		return reg;
1973 
1974 	reg = read_phy_reg(ohci, 8);
1975 	if (reg < 0)
1976 		return reg;
1977 
1978 	// set PMODE bit
1979 	reg |= 0x40;
1980 	reg = write_phy_reg(ohci, 8, reg);
1981 	if (reg < 0)
1982 		return reg;
1983 
1984 	// read register 12
1985 	reg = read_phy_reg(ohci, 12);
1986 	if (reg < 0)
1987 		return reg;
1988 
1989 	// bit 3 indicates "initiated reset"
1990 	*is_initiated_reset = !!((reg & 0x08) == 0x08);
1991 
1992 	return 0;
1993 }
1994 
1995 /*
1996  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1997  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1998  * Construct the selfID from phy register contents.
1999  */
2000 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
2001 {
2002 	int reg, i, pos, err;
2003 	bool is_initiated_reset;
2004 	u32 self_id = 0;
2005 
2006 	// link active 1, speed 3, bridge 0, contender 1, more packets 0.
2007 	phy_packet_set_packet_identifier(&self_id, PHY_PACKET_PACKET_IDENTIFIER_SELF_ID);
2008 	phy_packet_self_id_zero_set_link_active(&self_id, true);
2009 	phy_packet_self_id_zero_set_scode(&self_id, SCODE_800);
2010 	phy_packet_self_id_zero_set_contender(&self_id, true);
2011 
2012 	reg = reg_read(ohci, OHCI1394_NodeID);
2013 	if (!(reg & OHCI1394_NodeID_idValid)) {
2014 		ohci_notice(ohci,
2015 			    "node ID not valid, new bus reset in progress\n");
2016 		return -EBUSY;
2017 	}
2018 	phy_packet_self_id_set_phy_id(&self_id, reg & 0x3f);
2019 
2020 	reg = ohci_read_phy_reg(&ohci->card, 4);
2021 	if (reg < 0)
2022 		return reg;
2023 	phy_packet_self_id_zero_set_power_class(&self_id, reg & 0x07);
2024 
2025 	reg = ohci_read_phy_reg(&ohci->card, 1);
2026 	if (reg < 0)
2027 		return reg;
2028 	phy_packet_self_id_zero_set_gap_count(&self_id, reg & 0x3f);
2029 
2030 	for (i = 0; i < 3; i++) {
2031 		enum phy_packet_self_id_port_status status;
2032 
2033 		err = get_status_for_port(ohci, i, &status);
2034 		if (err < 0)
2035 			return err;
2036 
2037 		self_id_sequence_set_port_status(&self_id, 1, i, status);
2038 	}
2039 
2040 	err = detect_initiated_reset(ohci, &is_initiated_reset);
2041 	if (err < 0)
2042 		return err;
2043 	phy_packet_self_id_zero_set_initiated_reset(&self_id, is_initiated_reset);
2044 
2045 	pos = get_self_id_pos(ohci, self_id, self_id_count);
2046 	if (pos >= 0) {
2047 		memmove(&(ohci->self_id_buffer[pos+1]),
2048 			&(ohci->self_id_buffer[pos]),
2049 			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
2050 		ohci->self_id_buffer[pos] = self_id;
2051 		self_id_count++;
2052 	}
2053 	return self_id_count;
2054 }
2055 
2056 static void bus_reset_work(struct work_struct *work)
2057 {
2058 	struct fw_ohci *ohci =
2059 		container_of(work, struct fw_ohci, bus_reset_work);
2060 	int self_id_count, generation, new_generation, i, j;
2061 	u32 reg, quadlet;
2062 	void *free_rom = NULL;
2063 	dma_addr_t free_rom_bus = 0;
2064 	bool is_new_root;
2065 
2066 	reg = reg_read(ohci, OHCI1394_NodeID);
2067 	if (!(reg & OHCI1394_NodeID_idValid)) {
2068 		ohci_notice(ohci,
2069 			    "node ID not valid, new bus reset in progress\n");
2070 		return;
2071 	}
2072 	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
2073 		ohci_notice(ohci, "malconfigured bus\n");
2074 		return;
2075 	}
2076 	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
2077 			       OHCI1394_NodeID_nodeNumber);
2078 
2079 	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
2080 	if (!(ohci->is_root && is_new_root))
2081 		reg_write(ohci, OHCI1394_LinkControlSet,
2082 			  OHCI1394_LinkControl_cycleMaster);
2083 	ohci->is_root = is_new_root;
2084 
2085 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
2086 	if (ohci1394_self_id_count_is_error(reg)) {
2087 		ohci_notice(ohci, "self ID receive error\n");
2088 		return;
2089 	}
2090 	/*
2091 	 * The count in the SelfIDCount register is the number of
2092 	 * bytes in the self ID receive buffer.  Since we also receive
2093 	 * the inverted quadlets and a header quadlet, we shift one
2094 	 * bit extra to get the actual number of self IDs.
2095 	 */
2096 	self_id_count = ohci1394_self_id_count_get_size(reg) >> 1;
2097 
2098 	if (self_id_count > 252) {
2099 		ohci_notice(ohci, "bad selfIDSize (%08x)\n", reg);
2100 		return;
2101 	}
2102 
2103 	quadlet = cond_le32_to_cpu(ohci->self_id[0], has_be_header_quirk(ohci));
2104 	generation = ohci1394_self_id_receive_q0_get_generation(quadlet);
2105 	rmb();
2106 
2107 	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
2108 		u32 id  = cond_le32_to_cpu(ohci->self_id[i], has_be_header_quirk(ohci));
2109 		u32 id2 = cond_le32_to_cpu(ohci->self_id[i + 1], has_be_header_quirk(ohci));
2110 
2111 		if (id != ~id2) {
2112 			/*
2113 			 * If the invalid data looks like a cycle start packet,
2114 			 * it's likely to be the result of the cycle master
2115 			 * having a wrong gap count.  In this case, the self IDs
2116 			 * so far are valid and should be processed so that the
2117 			 * bus manager can then correct the gap count.
2118 			 */
2119 			if (id == 0xffff008f) {
2120 				ohci_notice(ohci, "ignoring spurious self IDs\n");
2121 				self_id_count = j;
2122 				break;
2123 			}
2124 
2125 			ohci_notice(ohci, "bad self ID %d/%d (%08x != ~%08x)\n",
2126 				    j, self_id_count, id, id2);
2127 			return;
2128 		}
2129 		ohci->self_id_buffer[j] = id;
2130 	}
2131 
2132 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2133 		self_id_count = find_and_insert_self_id(ohci, self_id_count);
2134 		if (self_id_count < 0) {
2135 			ohci_notice(ohci,
2136 				    "could not construct local self ID\n");
2137 			return;
2138 		}
2139 	}
2140 
2141 	if (self_id_count == 0) {
2142 		ohci_notice(ohci, "no self IDs\n");
2143 		return;
2144 	}
2145 	rmb();
2146 
2147 	/*
2148 	 * Check the consistency of the self IDs we just read.  The
2149 	 * problem we face is that a new bus reset can start while we
2150 	 * read out the self IDs from the DMA buffer. If this happens,
2151 	 * the DMA buffer will be overwritten with new self IDs and we
2152 	 * will read out inconsistent data.  The OHCI specification
2153 	 * (section 11.2) recommends a technique similar to
2154 	 * linux/seqlock.h, where we remember the generation of the
2155 	 * self IDs in the buffer before reading them out and compare
2156 	 * it to the current generation after reading them out.  If
2157 	 * the two generations match we know we have a consistent set
2158 	 * of self IDs.
2159 	 */
2160 
2161 	reg = reg_read(ohci, OHCI1394_SelfIDCount);
2162 	new_generation = ohci1394_self_id_count_get_generation(reg);
2163 	if (new_generation != generation) {
2164 		ohci_notice(ohci, "new bus reset, discarding self ids\n");
2165 		return;
2166 	}
2167 
2168 	// FIXME: Document how the locking works.
2169 	scoped_guard(spinlock_irq, &ohci->lock) {
2170 		ohci->generation = -1; // prevent AT packet queueing
2171 		context_stop(&ohci->at_request_ctx);
2172 		context_stop(&ohci->at_response_ctx);
2173 	}
2174 
2175 	/*
2176 	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
2177 	 * packets in the AT queues and software needs to drain them.
2178 	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
2179 	 */
2180 	at_context_flush(&ohci->at_request_ctx);
2181 	at_context_flush(&ohci->at_response_ctx);
2182 
2183 	scoped_guard(spinlock_irq, &ohci->lock) {
2184 		ohci->generation = generation;
2185 		reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
2186 		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_busReset);
2187 
2188 		if (ohci->quirks & QUIRK_RESET_PACKET)
2189 			ohci->request_generation = generation;
2190 
2191 		// This next bit is unrelated to the AT context stuff but we have to do it under the
2192 		// spinlock also. If a new config rom was set up before this reset, the old one is
2193 		// now no longer in use and we can free it. Update the config rom pointers to point
2194 		// to the current config rom and clear the next_config_rom pointer so a new update
2195 		// can take place.
2196 		if (ohci->next_config_rom != NULL) {
2197 			if (ohci->next_config_rom != ohci->config_rom) {
2198 				free_rom      = ohci->config_rom;
2199 				free_rom_bus  = ohci->config_rom_bus;
2200 			}
2201 			ohci->config_rom      = ohci->next_config_rom;
2202 			ohci->config_rom_bus  = ohci->next_config_rom_bus;
2203 			ohci->next_config_rom = NULL;
2204 
2205 			// Restore config_rom image and manually update config_rom registers.
2206 			// Writing the header quadlet will indicate that the config rom is ready,
2207 			// so we do that last.
2208 			reg_write(ohci, OHCI1394_BusOptions, be32_to_cpu(ohci->config_rom[2]));
2209 			ohci->config_rom[0] = ohci->next_header;
2210 			reg_write(ohci, OHCI1394_ConfigROMhdr, be32_to_cpu(ohci->next_header));
2211 		}
2212 
2213 		if (param_remote_dma) {
2214 			reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
2215 			reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
2216 		}
2217 	}
2218 
2219 	if (free_rom)
2220 		dmam_free_coherent(ohci->card.device, CONFIG_ROM_SIZE, free_rom, free_rom_bus);
2221 
2222 	log_selfids(ohci, generation, self_id_count);
2223 
2224 	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2225 				 self_id_count, ohci->self_id_buffer,
2226 				 ohci->csr_state_setclear_abdicate);
2227 	ohci->csr_state_setclear_abdicate = false;
2228 }
2229 
2230 static irqreturn_t irq_handler(int irq, void *data)
2231 {
2232 	struct fw_ohci *ohci = data;
2233 	u32 event, iso_event;
2234 	int i;
2235 
2236 	event = reg_read(ohci, OHCI1394_IntEventClear);
2237 
2238 	if (!event || !~event)
2239 		return IRQ_NONE;
2240 
2241 	if (unlikely(param_debug > 0)) {
2242 		dev_notice_ratelimited(ohci->card.device,
2243 				       "The debug parameter is superceded by tracepoints events, and deprecated.");
2244 	}
2245 
2246 	/*
2247 	 * busReset and postedWriteErr events must not be cleared yet
2248 	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2249 	 */
2250 	reg_write(ohci, OHCI1394_IntEventClear,
2251 		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2252 	trace_irqs(ohci->card.index, event);
2253 	log_irqs(ohci, event);
2254 	// The flag is masked again at bus_reset_work() scheduled by selfID event.
2255 	if (event & OHCI1394_busReset)
2256 		reg_write(ohci, OHCI1394_IntMaskClear, OHCI1394_busReset);
2257 
2258 	if (event & OHCI1394_selfIDComplete) {
2259 		if (trace_self_id_complete_enabled()) {
2260 			u32 reg = reg_read(ohci, OHCI1394_SelfIDCount);
2261 
2262 			trace_self_id_complete(ohci->card.index, reg, ohci->self_id,
2263 					       has_be_header_quirk(ohci));
2264 		}
2265 		queue_work(selfid_workqueue, &ohci->bus_reset_work);
2266 	}
2267 
2268 	if (event & OHCI1394_RQPkt)
2269 		tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2270 
2271 	if (event & OHCI1394_RSPkt)
2272 		tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2273 
2274 	if (event & OHCI1394_reqTxComplete)
2275 		tasklet_schedule(&ohci->at_request_ctx.tasklet);
2276 
2277 	if (event & OHCI1394_respTxComplete)
2278 		tasklet_schedule(&ohci->at_response_ctx.tasklet);
2279 
2280 	if (event & OHCI1394_isochRx) {
2281 		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2282 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2283 
2284 		while (iso_event) {
2285 			i = ffs(iso_event) - 1;
2286 			fw_iso_context_queue_work(&ohci->ir_context_list[i].base);
2287 			iso_event &= ~(1 << i);
2288 		}
2289 	}
2290 
2291 	if (event & OHCI1394_isochTx) {
2292 		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2293 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2294 
2295 		while (iso_event) {
2296 			i = ffs(iso_event) - 1;
2297 			fw_iso_context_queue_work(&ohci->it_context_list[i].base);
2298 			iso_event &= ~(1 << i);
2299 		}
2300 	}
2301 
2302 	if (unlikely(event & OHCI1394_regAccessFail))
2303 		ohci_err(ohci, "register access failure\n");
2304 
2305 	if (unlikely(event & OHCI1394_postedWriteErr)) {
2306 		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2307 		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2308 		reg_write(ohci, OHCI1394_IntEventClear,
2309 			  OHCI1394_postedWriteErr);
2310 		dev_err_ratelimited(ohci->card.device, "PCI posted write error\n");
2311 	}
2312 
2313 	if (unlikely(event & OHCI1394_cycleTooLong)) {
2314 		dev_notice_ratelimited(ohci->card.device, "isochronous cycle too long\n");
2315 		reg_write(ohci, OHCI1394_LinkControlSet,
2316 			  OHCI1394_LinkControl_cycleMaster);
2317 	}
2318 
2319 	if (unlikely(event & OHCI1394_cycleInconsistent)) {
2320 		/*
2321 		 * We need to clear this event bit in order to make
2322 		 * cycleMatch isochronous I/O work.  In theory we should
2323 		 * stop active cycleMatch iso contexts now and restart
2324 		 * them at least two cycles later.  (FIXME?)
2325 		 */
2326 		dev_notice_ratelimited(ohci->card.device, "isochronous cycle inconsistent\n");
2327 	}
2328 
2329 	if (unlikely(event & OHCI1394_unrecoverableError))
2330 		handle_dead_contexts(ohci);
2331 
2332 	if (event & OHCI1394_cycle64Seconds) {
2333 		guard(spinlock)(&ohci->lock);
2334 		update_bus_time(ohci);
2335 	} else
2336 		flush_writes(ohci);
2337 
2338 	return IRQ_HANDLED;
2339 }
2340 
2341 static int software_reset(struct fw_ohci *ohci)
2342 {
2343 	u32 val;
2344 	int i;
2345 
2346 	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2347 	for (i = 0; i < 500; i++) {
2348 		val = reg_read(ohci, OHCI1394_HCControlSet);
2349 		if (!~val)
2350 			return -ENODEV; /* Card was ejected. */
2351 
2352 		if (!(val & OHCI1394_HCControl_softReset))
2353 			return 0;
2354 
2355 		msleep(1);
2356 	}
2357 
2358 	return -EBUSY;
2359 }
2360 
2361 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2362 {
2363 	size_t size = length * 4;
2364 
2365 	memcpy(dest, src, size);
2366 	if (size < CONFIG_ROM_SIZE)
2367 		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2368 }
2369 
2370 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2371 {
2372 	bool enable_1394a;
2373 	int ret, clear, set, offset;
2374 
2375 	/* Check if the driver should configure link and PHY. */
2376 	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2377 	      OHCI1394_HCControl_programPhyEnable))
2378 		return 0;
2379 
2380 	/* Paranoia: check whether the PHY supports 1394a, too. */
2381 	enable_1394a = false;
2382 	ret = read_phy_reg(ohci, 2);
2383 	if (ret < 0)
2384 		return ret;
2385 	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2386 		ret = read_paged_phy_reg(ohci, 1, 8);
2387 		if (ret < 0)
2388 			return ret;
2389 		if (ret >= 1)
2390 			enable_1394a = true;
2391 	}
2392 
2393 	if (ohci->quirks & QUIRK_NO_1394A)
2394 		enable_1394a = false;
2395 
2396 	/* Configure PHY and link consistently. */
2397 	if (enable_1394a) {
2398 		clear = 0;
2399 		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2400 	} else {
2401 		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2402 		set = 0;
2403 	}
2404 	ret = update_phy_reg(ohci, 5, clear, set);
2405 	if (ret < 0)
2406 		return ret;
2407 
2408 	if (enable_1394a)
2409 		offset = OHCI1394_HCControlSet;
2410 	else
2411 		offset = OHCI1394_HCControlClear;
2412 	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2413 
2414 	/* Clean up: configuration has been taken care of. */
2415 	reg_write(ohci, OHCI1394_HCControlClear,
2416 		  OHCI1394_HCControl_programPhyEnable);
2417 
2418 	return 0;
2419 }
2420 
2421 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2422 {
2423 	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2424 	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2425 	int reg, i;
2426 
2427 	reg = read_phy_reg(ohci, 2);
2428 	if (reg < 0)
2429 		return reg;
2430 	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2431 		return 0;
2432 
2433 	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2434 		reg = read_paged_phy_reg(ohci, 1, i + 10);
2435 		if (reg < 0)
2436 			return reg;
2437 		if (reg != id[i])
2438 			return 0;
2439 	}
2440 	return 1;
2441 }
2442 
2443 static int ohci_enable(struct fw_card *card,
2444 		       const __be32 *config_rom, size_t length)
2445 {
2446 	struct fw_ohci *ohci = fw_ohci(card);
2447 	u32 lps, version, irqs;
2448 	int i, ret;
2449 
2450 	ret = software_reset(ohci);
2451 	if (ret < 0) {
2452 		ohci_err(ohci, "failed to reset ohci card\n");
2453 		return ret;
2454 	}
2455 
2456 	/*
2457 	 * Now enable LPS, which we need in order to start accessing
2458 	 * most of the registers.  In fact, on some cards (ALI M5251),
2459 	 * accessing registers in the SClk domain without LPS enabled
2460 	 * will lock up the machine.  Wait 50msec to make sure we have
2461 	 * full link enabled.  However, with some cards (well, at least
2462 	 * a JMicron PCIe card), we have to try again sometimes.
2463 	 *
2464 	 * TI TSB82AA2 + TSB81BA3(A) cards signal LPS enabled early but
2465 	 * cannot actually use the phy at that time.  These need tens of
2466 	 * millisecods pause between LPS write and first phy access too.
2467 	 */
2468 
2469 	reg_write(ohci, OHCI1394_HCControlSet,
2470 		  OHCI1394_HCControl_LPS |
2471 		  OHCI1394_HCControl_postedWriteEnable);
2472 	flush_writes(ohci);
2473 
2474 	for (lps = 0, i = 0; !lps && i < 3; i++) {
2475 		msleep(50);
2476 		lps = reg_read(ohci, OHCI1394_HCControlSet) &
2477 		      OHCI1394_HCControl_LPS;
2478 	}
2479 
2480 	if (!lps) {
2481 		ohci_err(ohci, "failed to set Link Power Status\n");
2482 		return -EIO;
2483 	}
2484 
2485 	if (ohci->quirks & QUIRK_TI_SLLZ059) {
2486 		ret = probe_tsb41ba3d(ohci);
2487 		if (ret < 0)
2488 			return ret;
2489 		if (ret)
2490 			ohci_notice(ohci, "local TSB41BA3D phy\n");
2491 		else
2492 			ohci->quirks &= ~QUIRK_TI_SLLZ059;
2493 	}
2494 
2495 	reg_write(ohci, OHCI1394_HCControlClear,
2496 		  OHCI1394_HCControl_noByteSwapData);
2497 
2498 	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2499 	reg_write(ohci, OHCI1394_LinkControlSet,
2500 		  OHCI1394_LinkControl_cycleTimerEnable |
2501 		  OHCI1394_LinkControl_cycleMaster);
2502 
2503 	reg_write(ohci, OHCI1394_ATRetries,
2504 		  OHCI1394_MAX_AT_REQ_RETRIES |
2505 		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2506 		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2507 		  (200 << 16));
2508 
2509 	ohci->bus_time_running = false;
2510 
2511 	for (i = 0; i < 32; i++)
2512 		if (ohci->ir_context_support & (1 << i))
2513 			reg_write(ohci, OHCI1394_IsoRcvContextControlClear(i),
2514 				  IR_CONTEXT_MULTI_CHANNEL_MODE);
2515 
2516 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2517 	if (version >= OHCI_VERSION_1_1) {
2518 		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2519 			  0xfffffffe);
2520 		card->broadcast_channel_auto_allocated = true;
2521 	}
2522 
2523 	/* Get implemented bits of the priority arbitration request counter. */
2524 	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2525 	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2526 	reg_write(ohci, OHCI1394_FairnessControl, 0);
2527 	card->priority_budget_implemented = ohci->pri_req_max != 0;
2528 
2529 	reg_write(ohci, OHCI1394_PhyUpperBound, FW_MAX_PHYSICAL_RANGE >> 16);
2530 	reg_write(ohci, OHCI1394_IntEventClear, ~0);
2531 	reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2532 
2533 	ret = configure_1394a_enhancements(ohci);
2534 	if (ret < 0)
2535 		return ret;
2536 
2537 	/* Activate link_on bit and contender bit in our self ID packets.*/
2538 	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2539 	if (ret < 0)
2540 		return ret;
2541 
2542 	/*
2543 	 * When the link is not yet enabled, the atomic config rom
2544 	 * update mechanism described below in ohci_set_config_rom()
2545 	 * is not active.  We have to update ConfigRomHeader and
2546 	 * BusOptions manually, and the write to ConfigROMmap takes
2547 	 * effect immediately.  We tie this to the enabling of the
2548 	 * link, so we have a valid config rom before enabling - the
2549 	 * OHCI requires that ConfigROMhdr and BusOptions have valid
2550 	 * values before enabling.
2551 	 *
2552 	 * However, when the ConfigROMmap is written, some controllers
2553 	 * always read back quadlets 0 and 2 from the config rom to
2554 	 * the ConfigRomHeader and BusOptions registers on bus reset.
2555 	 * They shouldn't do that in this initial case where the link
2556 	 * isn't enabled.  This means we have to use the same
2557 	 * workaround here, setting the bus header to 0 and then write
2558 	 * the right values in the bus reset tasklet.
2559 	 */
2560 
2561 	if (config_rom) {
2562 		ohci->next_config_rom = dmam_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2563 							    &ohci->next_config_rom_bus, GFP_KERNEL);
2564 		if (ohci->next_config_rom == NULL)
2565 			return -ENOMEM;
2566 
2567 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2568 	} else {
2569 		/*
2570 		 * In the suspend case, config_rom is NULL, which
2571 		 * means that we just reuse the old config rom.
2572 		 */
2573 		ohci->next_config_rom = ohci->config_rom;
2574 		ohci->next_config_rom_bus = ohci->config_rom_bus;
2575 	}
2576 
2577 	ohci->next_header = ohci->next_config_rom[0];
2578 	ohci->next_config_rom[0] = 0;
2579 	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2580 	reg_write(ohci, OHCI1394_BusOptions,
2581 		  be32_to_cpu(ohci->next_config_rom[2]));
2582 	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2583 
2584 	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2585 
2586 	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2587 		OHCI1394_RQPkt | OHCI1394_RSPkt |
2588 		OHCI1394_isochTx | OHCI1394_isochRx |
2589 		OHCI1394_postedWriteErr |
2590 		OHCI1394_selfIDComplete |
2591 		OHCI1394_regAccessFail |
2592 		OHCI1394_cycleInconsistent |
2593 		OHCI1394_unrecoverableError |
2594 		OHCI1394_cycleTooLong |
2595 		OHCI1394_masterIntEnable |
2596 		OHCI1394_busReset;
2597 	reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2598 
2599 	reg_write(ohci, OHCI1394_HCControlSet,
2600 		  OHCI1394_HCControl_linkEnable |
2601 		  OHCI1394_HCControl_BIBimageValid);
2602 
2603 	reg_write(ohci, OHCI1394_LinkControlSet,
2604 		  OHCI1394_LinkControl_rcvSelfID |
2605 		  OHCI1394_LinkControl_rcvPhyPkt);
2606 
2607 	ar_context_run(&ohci->ar_request_ctx);
2608 	ar_context_run(&ohci->ar_response_ctx);
2609 
2610 	flush_writes(ohci);
2611 
2612 	/* We are ready to go, reset bus to finish initialization. */
2613 	fw_schedule_bus_reset(&ohci->card, false, true);
2614 
2615 	return 0;
2616 }
2617 
2618 static int ohci_set_config_rom(struct fw_card *card,
2619 			       const __be32 *config_rom, size_t length)
2620 {
2621 	struct fw_ohci *ohci;
2622 	__be32 *next_config_rom;
2623 	dma_addr_t next_config_rom_bus;
2624 
2625 	ohci = fw_ohci(card);
2626 
2627 	/*
2628 	 * When the OHCI controller is enabled, the config rom update
2629 	 * mechanism is a bit tricky, but easy enough to use.  See
2630 	 * section 5.5.6 in the OHCI specification.
2631 	 *
2632 	 * The OHCI controller caches the new config rom address in a
2633 	 * shadow register (ConfigROMmapNext) and needs a bus reset
2634 	 * for the changes to take place.  When the bus reset is
2635 	 * detected, the controller loads the new values for the
2636 	 * ConfigRomHeader and BusOptions registers from the specified
2637 	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
2638 	 * shadow register. All automatically and atomically.
2639 	 *
2640 	 * Now, there's a twist to this story.  The automatic load of
2641 	 * ConfigRomHeader and BusOptions doesn't honor the
2642 	 * noByteSwapData bit, so with a be32 config rom, the
2643 	 * controller will load be32 values in to these registers
2644 	 * during the atomic update, even on litte endian
2645 	 * architectures.  The workaround we use is to put a 0 in the
2646 	 * header quadlet; 0 is endian agnostic and means that the
2647 	 * config rom isn't ready yet.  In the bus reset tasklet we
2648 	 * then set up the real values for the two registers.
2649 	 *
2650 	 * We use ohci->lock to avoid racing with the code that sets
2651 	 * ohci->next_config_rom to NULL (see bus_reset_work).
2652 	 */
2653 
2654 	next_config_rom = dmam_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2655 					      &next_config_rom_bus, GFP_KERNEL);
2656 	if (next_config_rom == NULL)
2657 		return -ENOMEM;
2658 
2659 	scoped_guard(spinlock_irq, &ohci->lock) {
2660 		// If there is not an already pending config_rom update, push our new allocation
2661 		// into the ohci->next_config_rom and then mark the local variable as null so that
2662 		// we won't deallocate the new buffer.
2663 		//
2664 		// OTOH, if there is a pending config_rom update, just use that buffer with the new
2665 		// config_rom data, and let this routine free the unused DMA allocation.
2666 		if (ohci->next_config_rom == NULL) {
2667 			ohci->next_config_rom = next_config_rom;
2668 			ohci->next_config_rom_bus = next_config_rom_bus;
2669 			next_config_rom = NULL;
2670 		}
2671 
2672 		copy_config_rom(ohci->next_config_rom, config_rom, length);
2673 
2674 		ohci->next_header = config_rom[0];
2675 		ohci->next_config_rom[0] = 0;
2676 
2677 		reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2678 	}
2679 
2680 	/* If we didn't use the DMA allocation, delete it. */
2681 	if (next_config_rom != NULL) {
2682 		dmam_free_coherent(ohci->card.device, CONFIG_ROM_SIZE, next_config_rom,
2683 				   next_config_rom_bus);
2684 	}
2685 
2686 	/*
2687 	 * Now initiate a bus reset to have the changes take
2688 	 * effect. We clean up the old config rom memory and DMA
2689 	 * mappings in the bus reset tasklet, since the OHCI
2690 	 * controller could need to access it before the bus reset
2691 	 * takes effect.
2692 	 */
2693 
2694 	fw_schedule_bus_reset(&ohci->card, true, true);
2695 
2696 	return 0;
2697 }
2698 
2699 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2700 {
2701 	struct fw_ohci *ohci = fw_ohci(card);
2702 
2703 	at_context_transmit(&ohci->at_request_ctx, packet);
2704 }
2705 
2706 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2707 {
2708 	struct fw_ohci *ohci = fw_ohci(card);
2709 
2710 	at_context_transmit(&ohci->at_response_ctx, packet);
2711 }
2712 
2713 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2714 {
2715 	struct fw_ohci *ohci = fw_ohci(card);
2716 	struct context *ctx = &ohci->at_request_ctx;
2717 	struct driver_data *driver_data = packet->driver_data;
2718 	int ret = -ENOENT;
2719 
2720 	tasklet_disable_in_atomic(&ctx->tasklet);
2721 
2722 	if (packet->ack != 0)
2723 		goto out;
2724 
2725 	if (packet->payload_mapped)
2726 		dma_unmap_single(ohci->card.device, packet->payload_bus,
2727 				 packet->payload_length, DMA_TO_DEVICE);
2728 
2729 	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2730 	driver_data->packet = NULL;
2731 	packet->ack = RCODE_CANCELLED;
2732 
2733 	// Timestamping on behalf of the hardware.
2734 	packet->timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ohci));
2735 
2736 	packet->callback(packet, &ohci->card, packet->ack);
2737 	ret = 0;
2738  out:
2739 	tasklet_enable(&ctx->tasklet);
2740 
2741 	return ret;
2742 }
2743 
2744 static int ohci_enable_phys_dma(struct fw_card *card,
2745 				int node_id, int generation)
2746 {
2747 	struct fw_ohci *ohci = fw_ohci(card);
2748 	int n, ret = 0;
2749 
2750 	if (param_remote_dma)
2751 		return 0;
2752 
2753 	/*
2754 	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2755 	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2756 	 */
2757 
2758 	guard(spinlock_irqsave)(&ohci->lock);
2759 
2760 	if (ohci->generation != generation)
2761 		return -ESTALE;
2762 
2763 	/*
2764 	 * Note, if the node ID contains a non-local bus ID, physical DMA is
2765 	 * enabled for _all_ nodes on remote buses.
2766 	 */
2767 
2768 	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2769 	if (n < 32)
2770 		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2771 	else
2772 		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2773 
2774 	flush_writes(ohci);
2775 
2776 	return ret;
2777 }
2778 
2779 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2780 {
2781 	struct fw_ohci *ohci = fw_ohci(card);
2782 	u32 value;
2783 
2784 	switch (csr_offset) {
2785 	case CSR_STATE_CLEAR:
2786 	case CSR_STATE_SET:
2787 		if (ohci->is_root &&
2788 		    (reg_read(ohci, OHCI1394_LinkControlSet) &
2789 		     OHCI1394_LinkControl_cycleMaster))
2790 			value = CSR_STATE_BIT_CMSTR;
2791 		else
2792 			value = 0;
2793 		if (ohci->csr_state_setclear_abdicate)
2794 			value |= CSR_STATE_BIT_ABDICATE;
2795 
2796 		return value;
2797 
2798 	case CSR_NODE_IDS:
2799 		return reg_read(ohci, OHCI1394_NodeID) << 16;
2800 
2801 	case CSR_CYCLE_TIME:
2802 		return get_cycle_time(ohci);
2803 
2804 	case CSR_BUS_TIME:
2805 	{
2806 		// We might be called just after the cycle timer has wrapped around but just before
2807 		// the cycle64Seconds handler, so we better check here, too, if the bus time needs
2808 		// to be updated.
2809 
2810 		guard(spinlock_irqsave)(&ohci->lock);
2811 		return update_bus_time(ohci);
2812 	}
2813 	case CSR_BUSY_TIMEOUT:
2814 		value = reg_read(ohci, OHCI1394_ATRetries);
2815 		return (value >> 4) & 0x0ffff00f;
2816 
2817 	case CSR_PRIORITY_BUDGET:
2818 		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2819 			(ohci->pri_req_max << 8);
2820 
2821 	default:
2822 		WARN_ON(1);
2823 		return 0;
2824 	}
2825 }
2826 
2827 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2828 {
2829 	struct fw_ohci *ohci = fw_ohci(card);
2830 
2831 	switch (csr_offset) {
2832 	case CSR_STATE_CLEAR:
2833 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2834 			reg_write(ohci, OHCI1394_LinkControlClear,
2835 				  OHCI1394_LinkControl_cycleMaster);
2836 			flush_writes(ohci);
2837 		}
2838 		if (value & CSR_STATE_BIT_ABDICATE)
2839 			ohci->csr_state_setclear_abdicate = false;
2840 		break;
2841 
2842 	case CSR_STATE_SET:
2843 		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2844 			reg_write(ohci, OHCI1394_LinkControlSet,
2845 				  OHCI1394_LinkControl_cycleMaster);
2846 			flush_writes(ohci);
2847 		}
2848 		if (value & CSR_STATE_BIT_ABDICATE)
2849 			ohci->csr_state_setclear_abdicate = true;
2850 		break;
2851 
2852 	case CSR_NODE_IDS:
2853 		reg_write(ohci, OHCI1394_NodeID, value >> 16);
2854 		flush_writes(ohci);
2855 		break;
2856 
2857 	case CSR_CYCLE_TIME:
2858 		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2859 		reg_write(ohci, OHCI1394_IntEventSet,
2860 			  OHCI1394_cycleInconsistent);
2861 		flush_writes(ohci);
2862 		break;
2863 
2864 	case CSR_BUS_TIME:
2865 	{
2866 		guard(spinlock_irqsave)(&ohci->lock);
2867 		ohci->bus_time = (update_bus_time(ohci) & 0x40) | (value & ~0x7f);
2868 		break;
2869 	}
2870 	case CSR_BUSY_TIMEOUT:
2871 		value = (value & 0xf) | ((value & 0xf) << 4) |
2872 			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2873 		reg_write(ohci, OHCI1394_ATRetries, value);
2874 		flush_writes(ohci);
2875 		break;
2876 
2877 	case CSR_PRIORITY_BUDGET:
2878 		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2879 		flush_writes(ohci);
2880 		break;
2881 
2882 	default:
2883 		WARN_ON(1);
2884 		break;
2885 	}
2886 }
2887 
2888 static void flush_iso_completions(struct iso_context *ctx, enum fw_iso_context_completions_cause cause)
2889 {
2890 	trace_isoc_inbound_single_completions(&ctx->base, ctx->last_timestamp, cause, ctx->header,
2891 					      ctx->header_length);
2892 	trace_isoc_outbound_completions(&ctx->base, ctx->last_timestamp, cause, ctx->header,
2893 					ctx->header_length);
2894 
2895 	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2896 			      ctx->header_length, ctx->header,
2897 			      ctx->base.callback_data);
2898 	ctx->header_length = 0;
2899 }
2900 
2901 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2902 {
2903 	u32 *ctx_hdr;
2904 
2905 	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE) {
2906 		if (ctx->base.drop_overflow_headers)
2907 			return;
2908 		flush_iso_completions(ctx, FW_ISO_CONTEXT_COMPLETIONS_CAUSE_HEADER_OVERFLOW);
2909 	}
2910 
2911 	ctx_hdr = ctx->header + ctx->header_length;
2912 	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2913 
2914 	/*
2915 	 * The two iso header quadlets are byteswapped to little
2916 	 * endian by the controller, but we want to present them
2917 	 * as big endian for consistency with the bus endianness.
2918 	 */
2919 	if (ctx->base.header_size > 0)
2920 		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2921 	if (ctx->base.header_size > 4)
2922 		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2923 	if (ctx->base.header_size > 8)
2924 		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2925 	ctx->header_length += ctx->base.header_size;
2926 }
2927 
2928 static int handle_ir_packet_per_buffer(struct context *context,
2929 				       struct descriptor *d,
2930 				       struct descriptor *last)
2931 {
2932 	struct iso_context *ctx =
2933 		container_of(context, struct iso_context, context);
2934 	struct descriptor *pd;
2935 	u32 buffer_dma;
2936 
2937 	for (pd = d; pd <= last; pd++)
2938 		if (pd->transfer_status)
2939 			break;
2940 	if (pd > last)
2941 		/* Descriptor(s) not done yet, stop iteration */
2942 		return 0;
2943 
2944 	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2945 		d++;
2946 		buffer_dma = le32_to_cpu(d->data_address);
2947 		dma_sync_single_range_for_cpu(context->ohci->card.device,
2948 					      buffer_dma & PAGE_MASK,
2949 					      buffer_dma & ~PAGE_MASK,
2950 					      le16_to_cpu(d->req_count),
2951 					      DMA_FROM_DEVICE);
2952 	}
2953 
2954 	copy_iso_headers(ctx, (u32 *) (last + 1));
2955 
2956 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2957 		flush_iso_completions(ctx, FW_ISO_CONTEXT_COMPLETIONS_CAUSE_IRQ);
2958 
2959 	return 1;
2960 }
2961 
2962 /* d == last because each descriptor block is only a single descriptor. */
2963 static int handle_ir_buffer_fill(struct context *context,
2964 				 struct descriptor *d,
2965 				 struct descriptor *last)
2966 {
2967 	struct iso_context *ctx =
2968 		container_of(context, struct iso_context, context);
2969 	unsigned int req_count, res_count, completed;
2970 	u32 buffer_dma;
2971 
2972 	req_count = le16_to_cpu(last->req_count);
2973 	res_count = le16_to_cpu(READ_ONCE(last->res_count));
2974 	completed = req_count - res_count;
2975 	buffer_dma = le32_to_cpu(last->data_address);
2976 
2977 	if (completed > 0) {
2978 		ctx->mc_buffer_bus = buffer_dma;
2979 		ctx->mc_completed = completed;
2980 	}
2981 
2982 	if (res_count != 0)
2983 		/* Descriptor(s) not done yet, stop iteration */
2984 		return 0;
2985 
2986 	dma_sync_single_range_for_cpu(context->ohci->card.device,
2987 				      buffer_dma & PAGE_MASK,
2988 				      buffer_dma & ~PAGE_MASK,
2989 				      completed, DMA_FROM_DEVICE);
2990 
2991 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2992 		trace_isoc_inbound_multiple_completions(&ctx->base, completed,
2993 							FW_ISO_CONTEXT_COMPLETIONS_CAUSE_IRQ);
2994 
2995 		ctx->base.callback.mc(&ctx->base,
2996 				      buffer_dma + completed,
2997 				      ctx->base.callback_data);
2998 		ctx->mc_completed = 0;
2999 	}
3000 
3001 	return 1;
3002 }
3003 
3004 static void flush_ir_buffer_fill(struct iso_context *ctx)
3005 {
3006 	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
3007 				      ctx->mc_buffer_bus & PAGE_MASK,
3008 				      ctx->mc_buffer_bus & ~PAGE_MASK,
3009 				      ctx->mc_completed, DMA_FROM_DEVICE);
3010 
3011 	trace_isoc_inbound_multiple_completions(&ctx->base, ctx->mc_completed,
3012 						FW_ISO_CONTEXT_COMPLETIONS_CAUSE_FLUSH);
3013 
3014 	ctx->base.callback.mc(&ctx->base,
3015 			      ctx->mc_buffer_bus + ctx->mc_completed,
3016 			      ctx->base.callback_data);
3017 	ctx->mc_completed = 0;
3018 }
3019 
3020 static inline void sync_it_packet_for_cpu(struct context *context,
3021 					  struct descriptor *pd)
3022 {
3023 	__le16 control;
3024 	u32 buffer_dma;
3025 
3026 	/* only packets beginning with OUTPUT_MORE* have data buffers */
3027 	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
3028 		return;
3029 
3030 	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
3031 	pd += 2;
3032 
3033 	/*
3034 	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
3035 	 * data buffer is in the context program's coherent page and must not
3036 	 * be synced.
3037 	 */
3038 	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
3039 	    (context->current_bus          & PAGE_MASK)) {
3040 		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
3041 			return;
3042 		pd++;
3043 	}
3044 
3045 	do {
3046 		buffer_dma = le32_to_cpu(pd->data_address);
3047 		dma_sync_single_range_for_cpu(context->ohci->card.device,
3048 					      buffer_dma & PAGE_MASK,
3049 					      buffer_dma & ~PAGE_MASK,
3050 					      le16_to_cpu(pd->req_count),
3051 					      DMA_TO_DEVICE);
3052 		control = pd->control;
3053 		pd++;
3054 	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
3055 }
3056 
3057 static int handle_it_packet(struct context *context,
3058 			    struct descriptor *d,
3059 			    struct descriptor *last)
3060 {
3061 	struct iso_context *ctx =
3062 		container_of(context, struct iso_context, context);
3063 	struct descriptor *pd;
3064 	__be32 *ctx_hdr;
3065 
3066 	for (pd = d; pd <= last; pd++)
3067 		if (pd->transfer_status)
3068 			break;
3069 	if (pd > last)
3070 		/* Descriptor(s) not done yet, stop iteration */
3071 		return 0;
3072 
3073 	sync_it_packet_for_cpu(context, d);
3074 
3075 	if (ctx->header_length + 4 > PAGE_SIZE) {
3076 		if (ctx->base.drop_overflow_headers)
3077 			return 1;
3078 		flush_iso_completions(ctx, FW_ISO_CONTEXT_COMPLETIONS_CAUSE_HEADER_OVERFLOW);
3079 	}
3080 
3081 	ctx_hdr = ctx->header + ctx->header_length;
3082 	ctx->last_timestamp = le16_to_cpu(last->res_count);
3083 	/* Present this value as big-endian to match the receive code */
3084 	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
3085 			       le16_to_cpu(pd->res_count));
3086 	ctx->header_length += 4;
3087 
3088 	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
3089 		flush_iso_completions(ctx, FW_ISO_CONTEXT_COMPLETIONS_CAUSE_IRQ);
3090 
3091 	return 1;
3092 }
3093 
3094 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
3095 {
3096 	u32 hi = channels >> 32, lo = channels;
3097 
3098 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
3099 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
3100 	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
3101 	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
3102 	ohci->mc_channels = channels;
3103 }
3104 
3105 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
3106 				int type, int channel, size_t header_size)
3107 {
3108 	struct fw_ohci *ohci = fw_ohci(card);
3109 	struct iso_context *ctx;
3110 	descriptor_callback_t callback;
3111 	u64 *channels;
3112 	u32 *mask, regs;
3113 	int index, ret = -EBUSY;
3114 
3115 	scoped_guard(spinlock_irq, &ohci->lock) {
3116 		switch (type) {
3117 		case FW_ISO_CONTEXT_TRANSMIT:
3118 			mask     = &ohci->it_context_mask;
3119 			callback = handle_it_packet;
3120 			index    = ffs(*mask) - 1;
3121 			if (index >= 0) {
3122 				*mask &= ~(1 << index);
3123 				regs = OHCI1394_IsoXmitContextBase(index);
3124 				ctx  = &ohci->it_context_list[index];
3125 			}
3126 			break;
3127 
3128 		case FW_ISO_CONTEXT_RECEIVE:
3129 			channels = &ohci->ir_context_channels;
3130 			mask     = &ohci->ir_context_mask;
3131 			callback = handle_ir_packet_per_buffer;
3132 			index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
3133 			if (index >= 0) {
3134 				*channels &= ~(1ULL << channel);
3135 				*mask     &= ~(1 << index);
3136 				regs = OHCI1394_IsoRcvContextBase(index);
3137 				ctx  = &ohci->ir_context_list[index];
3138 			}
3139 			break;
3140 
3141 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3142 			mask     = &ohci->ir_context_mask;
3143 			callback = handle_ir_buffer_fill;
3144 			index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
3145 			if (index >= 0) {
3146 				ohci->mc_allocated = true;
3147 				*mask &= ~(1 << index);
3148 				regs = OHCI1394_IsoRcvContextBase(index);
3149 				ctx  = &ohci->ir_context_list[index];
3150 			}
3151 			break;
3152 
3153 		default:
3154 			index = -1;
3155 			ret = -ENOSYS;
3156 		}
3157 
3158 		if (index < 0)
3159 			return ERR_PTR(ret);
3160 	}
3161 
3162 	memset(ctx, 0, sizeof(*ctx));
3163 	ctx->header_length = 0;
3164 	ctx->header = (void *) __get_free_page(GFP_KERNEL);
3165 	if (ctx->header == NULL) {
3166 		ret = -ENOMEM;
3167 		goto out;
3168 	}
3169 	ret = context_init(&ctx->context, ohci, regs, callback);
3170 	if (ret < 0)
3171 		goto out_with_header;
3172 	fw_iso_context_init_work(&ctx->base, ohci_isoc_context_work);
3173 
3174 	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
3175 		set_multichannel_mask(ohci, 0);
3176 		ctx->mc_completed = 0;
3177 	}
3178 
3179 	return &ctx->base;
3180 
3181  out_with_header:
3182 	free_page((unsigned long)ctx->header);
3183  out:
3184 	scoped_guard(spinlock_irq, &ohci->lock) {
3185 		switch (type) {
3186 		case FW_ISO_CONTEXT_RECEIVE:
3187 			*channels |= 1ULL << channel;
3188 			break;
3189 
3190 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3191 			ohci->mc_allocated = false;
3192 			break;
3193 		}
3194 		*mask |= 1 << index;
3195 	}
3196 
3197 	return ERR_PTR(ret);
3198 }
3199 
3200 static int ohci_start_iso(struct fw_iso_context *base,
3201 			  s32 cycle, u32 sync, u32 tags)
3202 {
3203 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3204 	struct fw_ohci *ohci = ctx->context.ohci;
3205 	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
3206 	int index;
3207 
3208 	/* the controller cannot start without any queued packets */
3209 	if (ctx->context.last->branch_address == 0)
3210 		return -ENODATA;
3211 
3212 	switch (ctx->base.type) {
3213 	case FW_ISO_CONTEXT_TRANSMIT:
3214 		index = ctx - ohci->it_context_list;
3215 		match = 0;
3216 		if (cycle >= 0)
3217 			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3218 				(cycle & 0x7fff) << 16;
3219 
3220 		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3221 		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3222 		context_run(&ctx->context, match);
3223 		break;
3224 
3225 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3226 		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3227 		fallthrough;
3228 	case FW_ISO_CONTEXT_RECEIVE:
3229 		index = ctx - ohci->ir_context_list;
3230 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
3231 		if (cycle >= 0) {
3232 			match |= (cycle & 0x07fff) << 12;
3233 			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3234 		}
3235 
3236 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3237 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3238 		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3239 		context_run(&ctx->context, control);
3240 
3241 		ctx->sync = sync;
3242 		ctx->tags = tags;
3243 
3244 		break;
3245 	}
3246 
3247 	return 0;
3248 }
3249 
3250 static int ohci_stop_iso(struct fw_iso_context *base)
3251 {
3252 	struct fw_ohci *ohci = fw_ohci(base->card);
3253 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3254 	int index;
3255 
3256 	switch (ctx->base.type) {
3257 	case FW_ISO_CONTEXT_TRANSMIT:
3258 		index = ctx - ohci->it_context_list;
3259 		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3260 		break;
3261 
3262 	case FW_ISO_CONTEXT_RECEIVE:
3263 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3264 		index = ctx - ohci->ir_context_list;
3265 		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3266 		break;
3267 	}
3268 	flush_writes(ohci);
3269 	context_stop(&ctx->context);
3270 
3271 	return 0;
3272 }
3273 
3274 static void ohci_free_iso_context(struct fw_iso_context *base)
3275 {
3276 	struct fw_ohci *ohci = fw_ohci(base->card);
3277 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3278 	int index;
3279 
3280 	ohci_stop_iso(base);
3281 	context_release(&ctx->context);
3282 	free_page((unsigned long)ctx->header);
3283 
3284 	guard(spinlock_irqsave)(&ohci->lock);
3285 
3286 	switch (base->type) {
3287 	case FW_ISO_CONTEXT_TRANSMIT:
3288 		index = ctx - ohci->it_context_list;
3289 		ohci->it_context_mask |= 1 << index;
3290 		break;
3291 
3292 	case FW_ISO_CONTEXT_RECEIVE:
3293 		index = ctx - ohci->ir_context_list;
3294 		ohci->ir_context_mask |= 1 << index;
3295 		ohci->ir_context_channels |= 1ULL << base->channel;
3296 		break;
3297 
3298 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3299 		index = ctx - ohci->ir_context_list;
3300 		ohci->ir_context_mask |= 1 << index;
3301 		ohci->ir_context_channels |= ohci->mc_channels;
3302 		ohci->mc_channels = 0;
3303 		ohci->mc_allocated = false;
3304 		break;
3305 	}
3306 }
3307 
3308 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3309 {
3310 	struct fw_ohci *ohci = fw_ohci(base->card);
3311 
3312 	switch (base->type) {
3313 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3314 	{
3315 		guard(spinlock_irqsave)(&ohci->lock);
3316 
3317 		// Don't allow multichannel to grab other contexts' channels.
3318 		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3319 			*channels = ohci->ir_context_channels;
3320 			return -EBUSY;
3321 		} else {
3322 			set_multichannel_mask(ohci, *channels);
3323 			return 0;
3324 		}
3325 	}
3326 	default:
3327 		return -EINVAL;
3328 	}
3329 }
3330 
3331 #ifdef CONFIG_PM
3332 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3333 {
3334 	int i;
3335 	struct iso_context *ctx;
3336 
3337 	for (i = 0 ; i < ohci->n_ir ; i++) {
3338 		ctx = &ohci->ir_context_list[i];
3339 		if (ctx->context.running)
3340 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3341 	}
3342 
3343 	for (i = 0 ; i < ohci->n_it ; i++) {
3344 		ctx = &ohci->it_context_list[i];
3345 		if (ctx->context.running)
3346 			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3347 	}
3348 }
3349 #endif
3350 
3351 static int queue_iso_transmit(struct iso_context *ctx,
3352 			      struct fw_iso_packet *packet,
3353 			      struct fw_iso_buffer *buffer,
3354 			      unsigned long payload)
3355 {
3356 	struct descriptor *d, *last, *pd;
3357 	struct fw_iso_packet *p;
3358 	__le32 *header;
3359 	dma_addr_t d_bus, page_bus;
3360 	u32 z, header_z, payload_z, irq;
3361 	u32 payload_index, payload_end_index, next_page_index;
3362 	int page, end_page, i, length, offset;
3363 
3364 	p = packet;
3365 	payload_index = payload;
3366 
3367 	if (p->skip)
3368 		z = 1;
3369 	else
3370 		z = 2;
3371 	if (p->header_length > 0)
3372 		z++;
3373 
3374 	/* Determine the first page the payload isn't contained in. */
3375 	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3376 	if (p->payload_length > 0)
3377 		payload_z = end_page - (payload_index >> PAGE_SHIFT);
3378 	else
3379 		payload_z = 0;
3380 
3381 	z += payload_z;
3382 
3383 	/* Get header size in number of descriptors. */
3384 	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3385 
3386 	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3387 	if (d == NULL)
3388 		return -ENOMEM;
3389 
3390 	if (!p->skip) {
3391 		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3392 		d[0].req_count = cpu_to_le16(8);
3393 		/*
3394 		 * Link the skip address to this descriptor itself.  This causes
3395 		 * a context to skip a cycle whenever lost cycles or FIFO
3396 		 * overruns occur, without dropping the data.  The application
3397 		 * should then decide whether this is an error condition or not.
3398 		 * FIXME:  Make the context's cycle-lost behaviour configurable?
3399 		 */
3400 		d[0].branch_address = cpu_to_le32(d_bus | z);
3401 
3402 		header = (__le32 *) &d[1];
3403 
3404 		ohci1394_it_data_set_speed(header, ctx->base.speed);
3405 		ohci1394_it_data_set_tag(header, p->tag);
3406 		ohci1394_it_data_set_channel(header, ctx->base.channel);
3407 		ohci1394_it_data_set_tcode(header, TCODE_STREAM_DATA);
3408 		ohci1394_it_data_set_sync(header, p->sy);
3409 
3410 		ohci1394_it_data_set_data_length(header, p->header_length + p->payload_length);
3411 	}
3412 
3413 	if (p->header_length > 0) {
3414 		d[2].req_count    = cpu_to_le16(p->header_length);
3415 		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3416 		memcpy(&d[z], p->header, p->header_length);
3417 	}
3418 
3419 	pd = d + z - payload_z;
3420 	payload_end_index = payload_index + p->payload_length;
3421 	for (i = 0; i < payload_z; i++) {
3422 		page               = payload_index >> PAGE_SHIFT;
3423 		offset             = payload_index & ~PAGE_MASK;
3424 		next_page_index    = (page + 1) << PAGE_SHIFT;
3425 		length             =
3426 			min(next_page_index, payload_end_index) - payload_index;
3427 		pd[i].req_count    = cpu_to_le16(length);
3428 
3429 		page_bus = page_private(buffer->pages[page]);
3430 		pd[i].data_address = cpu_to_le32(page_bus + offset);
3431 
3432 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3433 						 page_bus, offset, length,
3434 						 DMA_TO_DEVICE);
3435 
3436 		payload_index += length;
3437 	}
3438 
3439 	if (p->interrupt)
3440 		irq = DESCRIPTOR_IRQ_ALWAYS;
3441 	else
3442 		irq = DESCRIPTOR_NO_IRQ;
3443 
3444 	last = z == 2 ? d : d + z - 1;
3445 	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3446 				     DESCRIPTOR_STATUS |
3447 				     DESCRIPTOR_BRANCH_ALWAYS |
3448 				     irq);
3449 
3450 	context_append(&ctx->context, d, z, header_z);
3451 
3452 	return 0;
3453 }
3454 
3455 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3456 				       struct fw_iso_packet *packet,
3457 				       struct fw_iso_buffer *buffer,
3458 				       unsigned long payload)
3459 {
3460 	struct device *device = ctx->context.ohci->card.device;
3461 	struct descriptor *d, *pd;
3462 	dma_addr_t d_bus, page_bus;
3463 	u32 z, header_z, rest;
3464 	int i, j, length;
3465 	int page, offset, packet_count, header_size, payload_per_buffer;
3466 
3467 	/*
3468 	 * The OHCI controller puts the isochronous header and trailer in the
3469 	 * buffer, so we need at least 8 bytes.
3470 	 */
3471 	packet_count = packet->header_length / ctx->base.header_size;
3472 	header_size  = max(ctx->base.header_size, (size_t)8);
3473 
3474 	/* Get header size in number of descriptors. */
3475 	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3476 	page     = payload >> PAGE_SHIFT;
3477 	offset   = payload & ~PAGE_MASK;
3478 	payload_per_buffer = packet->payload_length / packet_count;
3479 
3480 	for (i = 0; i < packet_count; i++) {
3481 		/* d points to the header descriptor */
3482 		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3483 		d = context_get_descriptors(&ctx->context,
3484 				z + header_z, &d_bus);
3485 		if (d == NULL)
3486 			return -ENOMEM;
3487 
3488 		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3489 					      DESCRIPTOR_INPUT_MORE);
3490 		if (packet->skip && i == 0)
3491 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3492 		d->req_count    = cpu_to_le16(header_size);
3493 		d->res_count    = d->req_count;
3494 		d->transfer_status = 0;
3495 		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3496 
3497 		rest = payload_per_buffer;
3498 		pd = d;
3499 		for (j = 1; j < z; j++) {
3500 			pd++;
3501 			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3502 						  DESCRIPTOR_INPUT_MORE);
3503 
3504 			if (offset + rest < PAGE_SIZE)
3505 				length = rest;
3506 			else
3507 				length = PAGE_SIZE - offset;
3508 			pd->req_count = cpu_to_le16(length);
3509 			pd->res_count = pd->req_count;
3510 			pd->transfer_status = 0;
3511 
3512 			page_bus = page_private(buffer->pages[page]);
3513 			pd->data_address = cpu_to_le32(page_bus + offset);
3514 
3515 			dma_sync_single_range_for_device(device, page_bus,
3516 							 offset, length,
3517 							 DMA_FROM_DEVICE);
3518 
3519 			offset = (offset + length) & ~PAGE_MASK;
3520 			rest -= length;
3521 			if (offset == 0)
3522 				page++;
3523 		}
3524 		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3525 					  DESCRIPTOR_INPUT_LAST |
3526 					  DESCRIPTOR_BRANCH_ALWAYS);
3527 		if (packet->interrupt && i == packet_count - 1)
3528 			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3529 
3530 		context_append(&ctx->context, d, z, header_z);
3531 	}
3532 
3533 	return 0;
3534 }
3535 
3536 static int queue_iso_buffer_fill(struct iso_context *ctx,
3537 				 struct fw_iso_packet *packet,
3538 				 struct fw_iso_buffer *buffer,
3539 				 unsigned long payload)
3540 {
3541 	struct descriptor *d;
3542 	dma_addr_t d_bus, page_bus;
3543 	int page, offset, rest, z, i, length;
3544 
3545 	page   = payload >> PAGE_SHIFT;
3546 	offset = payload & ~PAGE_MASK;
3547 	rest   = packet->payload_length;
3548 
3549 	/* We need one descriptor for each page in the buffer. */
3550 	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3551 
3552 	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3553 		return -EFAULT;
3554 
3555 	for (i = 0; i < z; i++) {
3556 		d = context_get_descriptors(&ctx->context, 1, &d_bus);
3557 		if (d == NULL)
3558 			return -ENOMEM;
3559 
3560 		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3561 					 DESCRIPTOR_BRANCH_ALWAYS);
3562 		if (packet->skip && i == 0)
3563 			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3564 		if (packet->interrupt && i == z - 1)
3565 			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3566 
3567 		if (offset + rest < PAGE_SIZE)
3568 			length = rest;
3569 		else
3570 			length = PAGE_SIZE - offset;
3571 		d->req_count = cpu_to_le16(length);
3572 		d->res_count = d->req_count;
3573 		d->transfer_status = 0;
3574 
3575 		page_bus = page_private(buffer->pages[page]);
3576 		d->data_address = cpu_to_le32(page_bus + offset);
3577 
3578 		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3579 						 page_bus, offset, length,
3580 						 DMA_FROM_DEVICE);
3581 
3582 		rest -= length;
3583 		offset = 0;
3584 		page++;
3585 
3586 		context_append(&ctx->context, d, 1, 0);
3587 	}
3588 
3589 	return 0;
3590 }
3591 
3592 static int ohci_queue_iso(struct fw_iso_context *base,
3593 			  struct fw_iso_packet *packet,
3594 			  struct fw_iso_buffer *buffer,
3595 			  unsigned long payload)
3596 {
3597 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3598 
3599 	guard(spinlock_irqsave)(&ctx->context.ohci->lock);
3600 
3601 	switch (base->type) {
3602 	case FW_ISO_CONTEXT_TRANSMIT:
3603 		return queue_iso_transmit(ctx, packet, buffer, payload);
3604 	case FW_ISO_CONTEXT_RECEIVE:
3605 		return queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3606 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3607 		return queue_iso_buffer_fill(ctx, packet, buffer, payload);
3608 	default:
3609 		return -ENOSYS;
3610 	}
3611 }
3612 
3613 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3614 {
3615 	struct context *ctx =
3616 			&container_of(base, struct iso_context, base)->context;
3617 
3618 	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3619 }
3620 
3621 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3622 {
3623 	struct iso_context *ctx = container_of(base, struct iso_context, base);
3624 	int ret = 0;
3625 
3626 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3627 		ohci_isoc_context_work(&base->work);
3628 
3629 		switch (base->type) {
3630 		case FW_ISO_CONTEXT_TRANSMIT:
3631 		case FW_ISO_CONTEXT_RECEIVE:
3632 			if (ctx->header_length != 0)
3633 				flush_iso_completions(ctx, FW_ISO_CONTEXT_COMPLETIONS_CAUSE_FLUSH);
3634 			break;
3635 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3636 			if (ctx->mc_completed != 0)
3637 				flush_ir_buffer_fill(ctx);
3638 			break;
3639 		default:
3640 			ret = -ENOSYS;
3641 		}
3642 
3643 		clear_bit_unlock(0, &ctx->flushing_completions);
3644 		smp_mb__after_atomic();
3645 	}
3646 
3647 	return ret;
3648 }
3649 
3650 static const struct fw_card_driver ohci_driver = {
3651 	.enable			= ohci_enable,
3652 	.read_phy_reg		= ohci_read_phy_reg,
3653 	.update_phy_reg		= ohci_update_phy_reg,
3654 	.set_config_rom		= ohci_set_config_rom,
3655 	.send_request		= ohci_send_request,
3656 	.send_response		= ohci_send_response,
3657 	.cancel_packet		= ohci_cancel_packet,
3658 	.enable_phys_dma	= ohci_enable_phys_dma,
3659 	.read_csr		= ohci_read_csr,
3660 	.write_csr		= ohci_write_csr,
3661 
3662 	.allocate_iso_context	= ohci_allocate_iso_context,
3663 	.free_iso_context	= ohci_free_iso_context,
3664 	.set_iso_channels	= ohci_set_iso_channels,
3665 	.queue_iso		= ohci_queue_iso,
3666 	.flush_queue_iso	= ohci_flush_queue_iso,
3667 	.flush_iso_completions	= ohci_flush_iso_completions,
3668 	.start_iso		= ohci_start_iso,
3669 	.stop_iso		= ohci_stop_iso,
3670 };
3671 
3672 #ifdef CONFIG_PPC_PMAC
3673 static void pmac_ohci_on(struct pci_dev *dev)
3674 {
3675 	if (machine_is(powermac)) {
3676 		struct device_node *ofn = pci_device_to_OF_node(dev);
3677 
3678 		if (ofn) {
3679 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3680 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3681 		}
3682 	}
3683 }
3684 
3685 static void pmac_ohci_off(struct pci_dev *dev)
3686 {
3687 	if (machine_is(powermac)) {
3688 		struct device_node *ofn = pci_device_to_OF_node(dev);
3689 
3690 		if (ofn) {
3691 			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3692 			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3693 		}
3694 	}
3695 }
3696 #else
3697 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3698 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3699 #endif /* CONFIG_PPC_PMAC */
3700 
3701 static void release_ohci(struct device *dev, void *data)
3702 {
3703 	struct pci_dev *pdev = to_pci_dev(dev);
3704 	struct fw_ohci *ohci = pci_get_drvdata(pdev);
3705 
3706 	pmac_ohci_off(pdev);
3707 
3708 	ar_context_release(&ohci->ar_response_ctx);
3709 	ar_context_release(&ohci->ar_request_ctx);
3710 
3711 	dev_notice(dev, "removed fw-ohci device\n");
3712 }
3713 
3714 static int pci_probe(struct pci_dev *dev,
3715 			       const struct pci_device_id *ent)
3716 {
3717 	struct fw_ohci *ohci;
3718 	u32 bus_options, max_receive, link_speed, version;
3719 	u64 guid;
3720 	int i, flags, irq, err;
3721 	size_t size;
3722 
3723 	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3724 		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3725 		return -ENOSYS;
3726 	}
3727 
3728 	ohci = devres_alloc(release_ohci, sizeof(*ohci), GFP_KERNEL);
3729 	if (ohci == NULL)
3730 		return -ENOMEM;
3731 	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3732 	pci_set_drvdata(dev, ohci);
3733 	pmac_ohci_on(dev);
3734 	devres_add(&dev->dev, ohci);
3735 
3736 	err = pcim_enable_device(dev);
3737 	if (err) {
3738 		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3739 		return err;
3740 	}
3741 
3742 	pci_set_master(dev);
3743 	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3744 
3745 	spin_lock_init(&ohci->lock);
3746 	mutex_init(&ohci->phy_reg_mutex);
3747 
3748 	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3749 
3750 	if (!(pci_resource_flags(dev, 0) & IORESOURCE_MEM) ||
3751 	    pci_resource_len(dev, 0) < OHCI1394_REGISTER_SIZE) {
3752 		ohci_err(ohci, "invalid MMIO resource\n");
3753 		return -ENXIO;
3754 	}
3755 
3756 	err = pcim_iomap_regions(dev, 1 << 0, ohci_driver_name);
3757 	if (err) {
3758 		ohci_err(ohci, "request and map MMIO resource unavailable\n");
3759 		return -ENXIO;
3760 	}
3761 	ohci->registers = pcim_iomap_table(dev)[0];
3762 
3763 	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3764 		if ((ohci_quirks[i].vendor == dev->vendor) &&
3765 		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3766 		     ohci_quirks[i].device == dev->device) &&
3767 		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3768 		     ohci_quirks[i].revision >= dev->revision)) {
3769 			ohci->quirks = ohci_quirks[i].flags;
3770 			break;
3771 		}
3772 	if (param_quirks)
3773 		ohci->quirks = param_quirks;
3774 
3775 	if (detect_vt630x_with_asm1083_on_amd_ryzen_machine(dev))
3776 		ohci->quirks |= QUIRK_REBOOT_BY_CYCLE_TIMER_READ;
3777 
3778 	/*
3779 	 * Because dma_alloc_coherent() allocates at least one page,
3780 	 * we save space by using a common buffer for the AR request/
3781 	 * response descriptors and the self IDs buffer.
3782 	 */
3783 	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3784 	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3785 	ohci->misc_buffer = dmam_alloc_coherent(&dev->dev, PAGE_SIZE, &ohci->misc_buffer_bus,
3786 						GFP_KERNEL);
3787 	if (!ohci->misc_buffer)
3788 		return -ENOMEM;
3789 
3790 	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3791 			      OHCI1394_AsReqRcvContextControlSet);
3792 	if (err < 0)
3793 		return err;
3794 
3795 	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3796 			      OHCI1394_AsRspRcvContextControlSet);
3797 	if (err < 0)
3798 		return err;
3799 
3800 	err = context_init(&ohci->at_request_ctx, ohci,
3801 			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3802 	if (err < 0)
3803 		return err;
3804 
3805 	err = context_init(&ohci->at_response_ctx, ohci,
3806 			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3807 	if (err < 0)
3808 		return err;
3809 
3810 	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3811 	ohci->ir_context_channels = ~0ULL;
3812 	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3813 	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3814 	ohci->ir_context_mask = ohci->ir_context_support;
3815 	ohci->n_ir = hweight32(ohci->ir_context_mask);
3816 	size = sizeof(struct iso_context) * ohci->n_ir;
3817 	ohci->ir_context_list = devm_kzalloc(&dev->dev, size, GFP_KERNEL);
3818 	if (!ohci->ir_context_list)
3819 		return -ENOMEM;
3820 
3821 	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3822 	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3823 	/* JMicron JMB38x often shows 0 at first read, just ignore it */
3824 	if (!ohci->it_context_support) {
3825 		ohci_notice(ohci, "overriding IsoXmitIntMask\n");
3826 		ohci->it_context_support = 0xf;
3827 	}
3828 	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3829 	ohci->it_context_mask = ohci->it_context_support;
3830 	ohci->n_it = hweight32(ohci->it_context_mask);
3831 	size = sizeof(struct iso_context) * ohci->n_it;
3832 	ohci->it_context_list = devm_kzalloc(&dev->dev, size, GFP_KERNEL);
3833 	if (!ohci->it_context_list)
3834 		return -ENOMEM;
3835 
3836 	ohci->self_id     = ohci->misc_buffer     + PAGE_SIZE/2;
3837 	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3838 
3839 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
3840 	max_receive = (bus_options >> 12) & 0xf;
3841 	link_speed = bus_options & 0x7;
3842 	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3843 		reg_read(ohci, OHCI1394_GUIDLo);
3844 
3845 	flags = PCI_IRQ_INTX;
3846 	if (!(ohci->quirks & QUIRK_NO_MSI))
3847 		flags |= PCI_IRQ_MSI;
3848 	err = pci_alloc_irq_vectors(dev, 1, 1, flags);
3849 	if (err < 0)
3850 		return err;
3851 	irq = pci_irq_vector(dev, 0);
3852 	if (irq < 0) {
3853 		err = irq;
3854 		goto fail_msi;
3855 	}
3856 
3857 	err = request_threaded_irq(irq, irq_handler, NULL,
3858 				   pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED, ohci_driver_name,
3859 				   ohci);
3860 	if (err < 0) {
3861 		ohci_err(ohci, "failed to allocate interrupt %d\n", irq);
3862 		goto fail_msi;
3863 	}
3864 
3865 	err = fw_card_add(&ohci->card, max_receive, link_speed, guid, ohci->n_it + ohci->n_ir);
3866 	if (err)
3867 		goto fail_irq;
3868 
3869 	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3870 	ohci_notice(ohci,
3871 		    "added OHCI v%x.%x device as card %d, "
3872 		    "%d IR + %d IT contexts, quirks 0x%x%s\n",
3873 		    version >> 16, version & 0xff, ohci->card.index,
3874 		    ohci->n_ir, ohci->n_it, ohci->quirks,
3875 		    reg_read(ohci, OHCI1394_PhyUpperBound) ?
3876 			", physUB" : "");
3877 
3878 	return 0;
3879 
3880  fail_irq:
3881 	free_irq(irq, ohci);
3882  fail_msi:
3883 	pci_free_irq_vectors(dev);
3884 
3885 	return err;
3886 }
3887 
3888 static void pci_remove(struct pci_dev *dev)
3889 {
3890 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3891 	int irq;
3892 
3893 	/*
3894 	 * If the removal is happening from the suspend state, LPS won't be
3895 	 * enabled and host registers (eg., IntMaskClear) won't be accessible.
3896 	 */
3897 	if (reg_read(ohci, OHCI1394_HCControlSet) & OHCI1394_HCControl_LPS) {
3898 		reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3899 		flush_writes(ohci);
3900 	}
3901 	cancel_work_sync(&ohci->bus_reset_work);
3902 	fw_core_remove_card(&ohci->card);
3903 
3904 	/*
3905 	 * FIXME: Fail all pending packets here, now that the upper
3906 	 * layers can't queue any more.
3907 	 */
3908 
3909 	software_reset(ohci);
3910 
3911 	irq = pci_irq_vector(dev, 0);
3912 	if (irq >= 0)
3913 		free_irq(irq, ohci);
3914 	pci_free_irq_vectors(dev);
3915 
3916 	dev_notice(&dev->dev, "removing fw-ohci device\n");
3917 }
3918 
3919 #ifdef CONFIG_PM
3920 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3921 {
3922 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3923 	int err;
3924 
3925 	software_reset(ohci);
3926 	err = pci_save_state(dev);
3927 	if (err) {
3928 		ohci_err(ohci, "pci_save_state failed\n");
3929 		return err;
3930 	}
3931 	err = pci_set_power_state(dev, pci_choose_state(dev, state));
3932 	if (err)
3933 		ohci_err(ohci, "pci_set_power_state failed with %d\n", err);
3934 	pmac_ohci_off(dev);
3935 
3936 	return 0;
3937 }
3938 
3939 static int pci_resume(struct pci_dev *dev)
3940 {
3941 	struct fw_ohci *ohci = pci_get_drvdata(dev);
3942 	int err;
3943 
3944 	pmac_ohci_on(dev);
3945 	pci_set_power_state(dev, PCI_D0);
3946 	pci_restore_state(dev);
3947 	err = pci_enable_device(dev);
3948 	if (err) {
3949 		ohci_err(ohci, "pci_enable_device failed\n");
3950 		return err;
3951 	}
3952 
3953 	/* Some systems don't setup GUID register on resume from ram  */
3954 	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3955 					!reg_read(ohci, OHCI1394_GUIDHi)) {
3956 		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3957 		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3958 	}
3959 
3960 	err = ohci_enable(&ohci->card, NULL, 0);
3961 	if (err)
3962 		return err;
3963 
3964 	ohci_resume_iso_dma(ohci);
3965 
3966 	return 0;
3967 }
3968 #endif
3969 
3970 static const struct pci_device_id pci_table[] = {
3971 	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3972 	{ }
3973 };
3974 
3975 MODULE_DEVICE_TABLE(pci, pci_table);
3976 
3977 static struct pci_driver fw_ohci_pci_driver = {
3978 	.name		= ohci_driver_name,
3979 	.id_table	= pci_table,
3980 	.probe		= pci_probe,
3981 	.remove		= pci_remove,
3982 #ifdef CONFIG_PM
3983 	.resume		= pci_resume,
3984 	.suspend	= pci_suspend,
3985 #endif
3986 };
3987 
3988 static int __init fw_ohci_init(void)
3989 {
3990 	selfid_workqueue = alloc_workqueue(KBUILD_MODNAME, WQ_MEM_RECLAIM, 0);
3991 	if (!selfid_workqueue)
3992 		return -ENOMEM;
3993 
3994 	return pci_register_driver(&fw_ohci_pci_driver);
3995 }
3996 
3997 static void __exit fw_ohci_cleanup(void)
3998 {
3999 	pci_unregister_driver(&fw_ohci_pci_driver);
4000 	destroy_workqueue(selfid_workqueue);
4001 }
4002 
4003 module_init(fw_ohci_init);
4004 module_exit(fw_ohci_cleanup);
4005 
4006 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
4007 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
4008 MODULE_LICENSE("GPL");
4009 
4010 /* Provide a module alias so root-on-sbp2 initrds don't break. */
4011 MODULE_ALIAS("ohci1394");
4012