1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Core IEEE1394 transaction logic
4  *
5  * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
6  */
7 
8 #include <linux/bug.h>
9 #include <linux/completion.h>
10 #include <linux/device.h>
11 #include <linux/errno.h>
12 #include <linux/firewire.h>
13 #include <linux/firewire-constants.h>
14 #include <linux/fs.h>
15 #include <linux/init.h>
16 #include <linux/idr.h>
17 #include <linux/jiffies.h>
18 #include <linux/kernel.h>
19 #include <linux/list.h>
20 #include <linux/module.h>
21 #include <linux/rculist.h>
22 #include <linux/slab.h>
23 #include <linux/spinlock.h>
24 #include <linux/string.h>
25 #include <linux/timer.h>
26 #include <linux/types.h>
27 #include <linux/workqueue.h>
28 
29 #include <asm/byteorder.h>
30 
31 #include "core.h"
32 
33 #define HEADER_PRI(pri)			((pri) << 0)
34 #define HEADER_TCODE(tcode)		((tcode) << 4)
35 #define HEADER_RETRY(retry)		((retry) << 8)
36 #define HEADER_TLABEL(tlabel)		((tlabel) << 10)
37 #define HEADER_DESTINATION(destination)	((destination) << 16)
38 #define HEADER_SOURCE(source)		((source) << 16)
39 #define HEADER_RCODE(rcode)		((rcode) << 12)
40 #define HEADER_OFFSET_HIGH(offset_high)	((offset_high) << 0)
41 #define HEADER_DATA_LENGTH(length)	((length) << 16)
42 #define HEADER_EXTENDED_TCODE(tcode)	((tcode) << 0)
43 
44 #define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
45 #define HEADER_GET_TLABEL(q)		(((q) >> 10) & 0x3f)
46 #define HEADER_GET_RCODE(q)		(((q) >> 12) & 0x0f)
47 #define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
48 #define HEADER_GET_SOURCE(q)		(((q) >> 16) & 0xffff)
49 #define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
50 #define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
51 #define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
52 
53 #define HEADER_DESTINATION_IS_BROADCAST(q) \
54 	(((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
55 
56 #define PHY_PACKET_CONFIG	0x0
57 #define PHY_PACKET_LINK_ON	0x1
58 #define PHY_PACKET_SELF_ID	0x2
59 
60 #define PHY_CONFIG_GAP_COUNT(gap_count)	(((gap_count) << 16) | (1 << 22))
61 #define PHY_CONFIG_ROOT_ID(node_id)	((((node_id) & 0x3f) << 24) | (1 << 23))
62 #define PHY_IDENTIFIER(id)		((id) << 30)
63 
64 /* returns 0 if the split timeout handler is already running */
try_cancel_split_timeout(struct fw_transaction * t)65 static int try_cancel_split_timeout(struct fw_transaction *t)
66 {
67 	if (t->is_split_transaction)
68 		return del_timer(&t->split_timeout_timer);
69 	else
70 		return 1;
71 }
72 
close_transaction(struct fw_transaction * transaction,struct fw_card * card,int rcode)73 static int close_transaction(struct fw_transaction *transaction,
74 			     struct fw_card *card, int rcode)
75 {
76 	struct fw_transaction *t = NULL, *iter;
77 	unsigned long flags;
78 
79 	spin_lock_irqsave(&card->lock, flags);
80 	list_for_each_entry(iter, &card->transaction_list, link) {
81 		if (iter == transaction) {
82 			if (!try_cancel_split_timeout(iter)) {
83 				spin_unlock_irqrestore(&card->lock, flags);
84 				goto timed_out;
85 			}
86 			list_del_init(&iter->link);
87 			card->tlabel_mask &= ~(1ULL << iter->tlabel);
88 			t = iter;
89 			break;
90 		}
91 	}
92 	spin_unlock_irqrestore(&card->lock, flags);
93 
94 	if (t) {
95 		t->callback(card, rcode, NULL, 0, t->callback_data);
96 		return 0;
97 	}
98 
99  timed_out:
100 	return -ENOENT;
101 }
102 
103 /*
104  * Only valid for transactions that are potentially pending (ie have
105  * been sent).
106  */
fw_cancel_transaction(struct fw_card * card,struct fw_transaction * transaction)107 int fw_cancel_transaction(struct fw_card *card,
108 			  struct fw_transaction *transaction)
109 {
110 	/*
111 	 * Cancel the packet transmission if it's still queued.  That
112 	 * will call the packet transmission callback which cancels
113 	 * the transaction.
114 	 */
115 
116 	if (card->driver->cancel_packet(card, &transaction->packet) == 0)
117 		return 0;
118 
119 	/*
120 	 * If the request packet has already been sent, we need to see
121 	 * if the transaction is still pending and remove it in that case.
122 	 */
123 
124 	return close_transaction(transaction, card, RCODE_CANCELLED);
125 }
126 EXPORT_SYMBOL(fw_cancel_transaction);
127 
split_transaction_timeout_callback(struct timer_list * timer)128 static void split_transaction_timeout_callback(struct timer_list *timer)
129 {
130 	struct fw_transaction *t = from_timer(t, timer, split_timeout_timer);
131 	struct fw_card *card = t->card;
132 	unsigned long flags;
133 
134 	spin_lock_irqsave(&card->lock, flags);
135 	if (list_empty(&t->link)) {
136 		spin_unlock_irqrestore(&card->lock, flags);
137 		return;
138 	}
139 	list_del(&t->link);
140 	card->tlabel_mask &= ~(1ULL << t->tlabel);
141 	spin_unlock_irqrestore(&card->lock, flags);
142 
143 	t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
144 }
145 
start_split_transaction_timeout(struct fw_transaction * t,struct fw_card * card)146 static void start_split_transaction_timeout(struct fw_transaction *t,
147 					    struct fw_card *card)
148 {
149 	unsigned long flags;
150 
151 	spin_lock_irqsave(&card->lock, flags);
152 
153 	if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
154 		spin_unlock_irqrestore(&card->lock, flags);
155 		return;
156 	}
157 
158 	t->is_split_transaction = true;
159 	mod_timer(&t->split_timeout_timer,
160 		  jiffies + card->split_timeout_jiffies);
161 
162 	spin_unlock_irqrestore(&card->lock, flags);
163 }
164 
transmit_complete_callback(struct fw_packet * packet,struct fw_card * card,int status)165 static void transmit_complete_callback(struct fw_packet *packet,
166 				       struct fw_card *card, int status)
167 {
168 	struct fw_transaction *t =
169 	    container_of(packet, struct fw_transaction, packet);
170 
171 	switch (status) {
172 	case ACK_COMPLETE:
173 		close_transaction(t, card, RCODE_COMPLETE);
174 		break;
175 	case ACK_PENDING:
176 		start_split_transaction_timeout(t, card);
177 		break;
178 	case ACK_BUSY_X:
179 	case ACK_BUSY_A:
180 	case ACK_BUSY_B:
181 		close_transaction(t, card, RCODE_BUSY);
182 		break;
183 	case ACK_DATA_ERROR:
184 		close_transaction(t, card, RCODE_DATA_ERROR);
185 		break;
186 	case ACK_TYPE_ERROR:
187 		close_transaction(t, card, RCODE_TYPE_ERROR);
188 		break;
189 	default:
190 		/*
191 		 * In this case the ack is really a juju specific
192 		 * rcode, so just forward that to the callback.
193 		 */
194 		close_transaction(t, card, status);
195 		break;
196 	}
197 }
198 
fw_fill_request(struct fw_packet * packet,int tcode,int tlabel,int destination_id,int source_id,int generation,int speed,unsigned long long offset,void * payload,size_t length)199 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
200 		int destination_id, int source_id, int generation, int speed,
201 		unsigned long long offset, void *payload, size_t length)
202 {
203 	int ext_tcode;
204 
205 	if (tcode == TCODE_STREAM_DATA) {
206 		packet->header[0] =
207 			HEADER_DATA_LENGTH(length) |
208 			destination_id |
209 			HEADER_TCODE(TCODE_STREAM_DATA);
210 		packet->header_length = 4;
211 		packet->payload = payload;
212 		packet->payload_length = length;
213 
214 		goto common;
215 	}
216 
217 	if (tcode > 0x10) {
218 		ext_tcode = tcode & ~0x10;
219 		tcode = TCODE_LOCK_REQUEST;
220 	} else
221 		ext_tcode = 0;
222 
223 	packet->header[0] =
224 		HEADER_RETRY(RETRY_X) |
225 		HEADER_TLABEL(tlabel) |
226 		HEADER_TCODE(tcode) |
227 		HEADER_DESTINATION(destination_id);
228 	packet->header[1] =
229 		HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
230 	packet->header[2] =
231 		offset;
232 
233 	switch (tcode) {
234 	case TCODE_WRITE_QUADLET_REQUEST:
235 		packet->header[3] = *(u32 *)payload;
236 		packet->header_length = 16;
237 		packet->payload_length = 0;
238 		break;
239 
240 	case TCODE_LOCK_REQUEST:
241 	case TCODE_WRITE_BLOCK_REQUEST:
242 		packet->header[3] =
243 			HEADER_DATA_LENGTH(length) |
244 			HEADER_EXTENDED_TCODE(ext_tcode);
245 		packet->header_length = 16;
246 		packet->payload = payload;
247 		packet->payload_length = length;
248 		break;
249 
250 	case TCODE_READ_QUADLET_REQUEST:
251 		packet->header_length = 12;
252 		packet->payload_length = 0;
253 		break;
254 
255 	case TCODE_READ_BLOCK_REQUEST:
256 		packet->header[3] =
257 			HEADER_DATA_LENGTH(length) |
258 			HEADER_EXTENDED_TCODE(ext_tcode);
259 		packet->header_length = 16;
260 		packet->payload_length = 0;
261 		break;
262 
263 	default:
264 		WARN(1, "wrong tcode %d\n", tcode);
265 	}
266  common:
267 	packet->speed = speed;
268 	packet->generation = generation;
269 	packet->ack = 0;
270 	packet->payload_mapped = false;
271 }
272 
allocate_tlabel(struct fw_card * card)273 static int allocate_tlabel(struct fw_card *card)
274 {
275 	int tlabel;
276 
277 	tlabel = card->current_tlabel;
278 	while (card->tlabel_mask & (1ULL << tlabel)) {
279 		tlabel = (tlabel + 1) & 0x3f;
280 		if (tlabel == card->current_tlabel)
281 			return -EBUSY;
282 	}
283 
284 	card->current_tlabel = (tlabel + 1) & 0x3f;
285 	card->tlabel_mask |= 1ULL << tlabel;
286 
287 	return tlabel;
288 }
289 
290 /**
291  * fw_send_request() - submit a request packet for transmission
292  * @card:		interface to send the request at
293  * @t:			transaction instance to which the request belongs
294  * @tcode:		transaction code
295  * @destination_id:	destination node ID, consisting of bus_ID and phy_ID
296  * @generation:		bus generation in which request and response are valid
297  * @speed:		transmission speed
298  * @offset:		48bit wide offset into destination's address space
299  * @payload:		data payload for the request subaction
300  * @length:		length of the payload, in bytes
301  * @callback:		function to be called when the transaction is completed
302  * @callback_data:	data to be passed to the transaction completion callback
303  *
304  * Submit a request packet into the asynchronous request transmission queue.
305  * Can be called from atomic context.  If you prefer a blocking API, use
306  * fw_run_transaction() in a context that can sleep.
307  *
308  * In case of lock requests, specify one of the firewire-core specific %TCODE_
309  * constants instead of %TCODE_LOCK_REQUEST in @tcode.
310  *
311  * Make sure that the value in @destination_id is not older than the one in
312  * @generation.  Otherwise the request is in danger to be sent to a wrong node.
313  *
314  * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
315  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
316  * It will contain tag, channel, and sy data instead of a node ID then.
317  *
318  * The payload buffer at @data is going to be DMA-mapped except in case of
319  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
320  * buffer complies with the restrictions of the streaming DMA mapping API.
321  * @payload must not be freed before the @callback is called.
322  *
323  * In case of request types without payload, @data is NULL and @length is 0.
324  *
325  * After the transaction is completed successfully or unsuccessfully, the
326  * @callback will be called.  Among its parameters is the response code which
327  * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
328  * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
329  * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
330  * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
331  * generation, or missing ACK respectively.
332  *
333  * Note some timing corner cases:  fw_send_request() may complete much earlier
334  * than when the request packet actually hits the wire.  On the other hand,
335  * transaction completion and hence execution of @callback may happen even
336  * before fw_send_request() returns.
337  */
fw_send_request(struct fw_card * card,struct fw_transaction * t,int tcode,int destination_id,int generation,int speed,unsigned long long offset,void * payload,size_t length,fw_transaction_callback_t callback,void * callback_data)338 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
339 		     int destination_id, int generation, int speed,
340 		     unsigned long long offset, void *payload, size_t length,
341 		     fw_transaction_callback_t callback, void *callback_data)
342 {
343 	unsigned long flags;
344 	int tlabel;
345 
346 	/*
347 	 * Allocate tlabel from the bitmap and put the transaction on
348 	 * the list while holding the card spinlock.
349 	 */
350 
351 	spin_lock_irqsave(&card->lock, flags);
352 
353 	tlabel = allocate_tlabel(card);
354 	if (tlabel < 0) {
355 		spin_unlock_irqrestore(&card->lock, flags);
356 		callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
357 		return;
358 	}
359 
360 	t->node_id = destination_id;
361 	t->tlabel = tlabel;
362 	t->card = card;
363 	t->is_split_transaction = false;
364 	timer_setup(&t->split_timeout_timer,
365 		    split_transaction_timeout_callback, 0);
366 	t->callback = callback;
367 	t->callback_data = callback_data;
368 
369 	fw_fill_request(&t->packet, tcode, t->tlabel,
370 			destination_id, card->node_id, generation,
371 			speed, offset, payload, length);
372 	t->packet.callback = transmit_complete_callback;
373 
374 	list_add_tail(&t->link, &card->transaction_list);
375 
376 	spin_unlock_irqrestore(&card->lock, flags);
377 
378 	card->driver->send_request(card, &t->packet);
379 }
380 EXPORT_SYMBOL(fw_send_request);
381 
382 struct transaction_callback_data {
383 	struct completion done;
384 	void *payload;
385 	int rcode;
386 };
387 
transaction_callback(struct fw_card * card,int rcode,void * payload,size_t length,void * data)388 static void transaction_callback(struct fw_card *card, int rcode,
389 				 void *payload, size_t length, void *data)
390 {
391 	struct transaction_callback_data *d = data;
392 
393 	if (rcode == RCODE_COMPLETE)
394 		memcpy(d->payload, payload, length);
395 	d->rcode = rcode;
396 	complete(&d->done);
397 }
398 
399 /**
400  * fw_run_transaction() - send request and sleep until transaction is completed
401  * @card:		card interface for this request
402  * @tcode:		transaction code
403  * @destination_id:	destination node ID, consisting of bus_ID and phy_ID
404  * @generation:		bus generation in which request and response are valid
405  * @speed:		transmission speed
406  * @offset:		48bit wide offset into destination's address space
407  * @payload:		data payload for the request subaction
408  * @length:		length of the payload, in bytes
409  *
410  * Returns the RCODE.  See fw_send_request() for parameter documentation.
411  * Unlike fw_send_request(), @data points to the payload of the request or/and
412  * to the payload of the response.  DMA mapping restrictions apply to outbound
413  * request payloads of >= 8 bytes but not to inbound response payloads.
414  */
fw_run_transaction(struct fw_card * card,int tcode,int destination_id,int generation,int speed,unsigned long long offset,void * payload,size_t length)415 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
416 		       int generation, int speed, unsigned long long offset,
417 		       void *payload, size_t length)
418 {
419 	struct transaction_callback_data d;
420 	struct fw_transaction t;
421 
422 	timer_setup_on_stack(&t.split_timeout_timer, NULL, 0);
423 	init_completion(&d.done);
424 	d.payload = payload;
425 	fw_send_request(card, &t, tcode, destination_id, generation, speed,
426 			offset, payload, length, transaction_callback, &d);
427 	wait_for_completion(&d.done);
428 	destroy_timer_on_stack(&t.split_timeout_timer);
429 
430 	return d.rcode;
431 }
432 EXPORT_SYMBOL(fw_run_transaction);
433 
434 static DEFINE_MUTEX(phy_config_mutex);
435 static DECLARE_COMPLETION(phy_config_done);
436 
transmit_phy_packet_callback(struct fw_packet * packet,struct fw_card * card,int status)437 static void transmit_phy_packet_callback(struct fw_packet *packet,
438 					 struct fw_card *card, int status)
439 {
440 	complete(&phy_config_done);
441 }
442 
443 static struct fw_packet phy_config_packet = {
444 	.header_length	= 12,
445 	.header[0]	= TCODE_LINK_INTERNAL << 4,
446 	.payload_length	= 0,
447 	.speed		= SCODE_100,
448 	.callback	= transmit_phy_packet_callback,
449 };
450 
fw_send_phy_config(struct fw_card * card,int node_id,int generation,int gap_count)451 void fw_send_phy_config(struct fw_card *card,
452 			int node_id, int generation, int gap_count)
453 {
454 	long timeout = DIV_ROUND_UP(HZ, 10);
455 	u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
456 
457 	if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
458 		data |= PHY_CONFIG_ROOT_ID(node_id);
459 
460 	if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
461 		gap_count = card->driver->read_phy_reg(card, 1);
462 		if (gap_count < 0)
463 			return;
464 
465 		gap_count &= 63;
466 		if (gap_count == 63)
467 			return;
468 	}
469 	data |= PHY_CONFIG_GAP_COUNT(gap_count);
470 
471 	mutex_lock(&phy_config_mutex);
472 
473 	phy_config_packet.header[1] = data;
474 	phy_config_packet.header[2] = ~data;
475 	phy_config_packet.generation = generation;
476 	reinit_completion(&phy_config_done);
477 
478 	card->driver->send_request(card, &phy_config_packet);
479 	wait_for_completion_timeout(&phy_config_done, timeout);
480 
481 	mutex_unlock(&phy_config_mutex);
482 }
483 
lookup_overlapping_address_handler(struct list_head * list,unsigned long long offset,size_t length)484 static struct fw_address_handler *lookup_overlapping_address_handler(
485 	struct list_head *list, unsigned long long offset, size_t length)
486 {
487 	struct fw_address_handler *handler;
488 
489 	list_for_each_entry_rcu(handler, list, link) {
490 		if (handler->offset < offset + length &&
491 		    offset < handler->offset + handler->length)
492 			return handler;
493 	}
494 
495 	return NULL;
496 }
497 
is_enclosing_handler(struct fw_address_handler * handler,unsigned long long offset,size_t length)498 static bool is_enclosing_handler(struct fw_address_handler *handler,
499 				 unsigned long long offset, size_t length)
500 {
501 	return handler->offset <= offset &&
502 		offset + length <= handler->offset + handler->length;
503 }
504 
lookup_enclosing_address_handler(struct list_head * list,unsigned long long offset,size_t length)505 static struct fw_address_handler *lookup_enclosing_address_handler(
506 	struct list_head *list, unsigned long long offset, size_t length)
507 {
508 	struct fw_address_handler *handler;
509 
510 	list_for_each_entry_rcu(handler, list, link) {
511 		if (is_enclosing_handler(handler, offset, length))
512 			return handler;
513 	}
514 
515 	return NULL;
516 }
517 
518 static DEFINE_SPINLOCK(address_handler_list_lock);
519 static LIST_HEAD(address_handler_list);
520 
521 const struct fw_address_region fw_high_memory_region =
522 	{ .start = FW_MAX_PHYSICAL_RANGE, .end = 0xffffe0000000ULL, };
523 EXPORT_SYMBOL(fw_high_memory_region);
524 
525 static const struct fw_address_region low_memory_region =
526 	{ .start = 0x000000000000ULL, .end = FW_MAX_PHYSICAL_RANGE, };
527 
528 #if 0
529 const struct fw_address_region fw_private_region =
530 	{ .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
531 const struct fw_address_region fw_csr_region =
532 	{ .start = CSR_REGISTER_BASE,
533 	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
534 const struct fw_address_region fw_unit_space_region =
535 	{ .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
536 #endif  /*  0  */
537 
is_in_fcp_region(u64 offset,size_t length)538 static bool is_in_fcp_region(u64 offset, size_t length)
539 {
540 	return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
541 		offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
542 }
543 
544 /**
545  * fw_core_add_address_handler() - register for incoming requests
546  * @handler:	callback
547  * @region:	region in the IEEE 1212 node space address range
548  *
549  * region->start, ->end, and handler->length have to be quadlet-aligned.
550  *
551  * When a request is received that falls within the specified address range,
552  * the specified callback is invoked.  The parameters passed to the callback
553  * give the details of the particular request.
554  *
555  * To be called in process context.
556  * Return value:  0 on success, non-zero otherwise.
557  *
558  * The start offset of the handler's address region is determined by
559  * fw_core_add_address_handler() and is returned in handler->offset.
560  *
561  * Address allocations are exclusive, except for the FCP registers.
562  */
fw_core_add_address_handler(struct fw_address_handler * handler,const struct fw_address_region * region)563 int fw_core_add_address_handler(struct fw_address_handler *handler,
564 				const struct fw_address_region *region)
565 {
566 	struct fw_address_handler *other;
567 	int ret = -EBUSY;
568 
569 	if (region->start & 0xffff000000000003ULL ||
570 	    region->start >= region->end ||
571 	    region->end   > 0x0001000000000000ULL ||
572 	    handler->length & 3 ||
573 	    handler->length == 0)
574 		return -EINVAL;
575 
576 	spin_lock(&address_handler_list_lock);
577 
578 	handler->offset = region->start;
579 	while (handler->offset + handler->length <= region->end) {
580 		if (is_in_fcp_region(handler->offset, handler->length))
581 			other = NULL;
582 		else
583 			other = lookup_overlapping_address_handler
584 					(&address_handler_list,
585 					 handler->offset, handler->length);
586 		if (other != NULL) {
587 			handler->offset += other->length;
588 		} else {
589 			list_add_tail_rcu(&handler->link, &address_handler_list);
590 			ret = 0;
591 			break;
592 		}
593 	}
594 
595 	spin_unlock(&address_handler_list_lock);
596 
597 	return ret;
598 }
599 EXPORT_SYMBOL(fw_core_add_address_handler);
600 
601 /**
602  * fw_core_remove_address_handler() - unregister an address handler
603  * @handler: callback
604  *
605  * To be called in process context.
606  *
607  * When fw_core_remove_address_handler() returns, @handler->callback() is
608  * guaranteed to not run on any CPU anymore.
609  */
fw_core_remove_address_handler(struct fw_address_handler * handler)610 void fw_core_remove_address_handler(struct fw_address_handler *handler)
611 {
612 	spin_lock(&address_handler_list_lock);
613 	list_del_rcu(&handler->link);
614 	spin_unlock(&address_handler_list_lock);
615 	synchronize_rcu();
616 }
617 EXPORT_SYMBOL(fw_core_remove_address_handler);
618 
619 struct fw_request {
620 	struct fw_packet response;
621 	u32 request_header[4];
622 	int ack;
623 	u32 timestamp;
624 	u32 length;
625 	u32 data[];
626 };
627 
free_response_callback(struct fw_packet * packet,struct fw_card * card,int status)628 static void free_response_callback(struct fw_packet *packet,
629 				   struct fw_card *card, int status)
630 {
631 	struct fw_request *request;
632 
633 	request = container_of(packet, struct fw_request, response);
634 	kfree(request);
635 }
636 
fw_get_response_length(struct fw_request * r)637 int fw_get_response_length(struct fw_request *r)
638 {
639 	int tcode, ext_tcode, data_length;
640 
641 	tcode = HEADER_GET_TCODE(r->request_header[0]);
642 
643 	switch (tcode) {
644 	case TCODE_WRITE_QUADLET_REQUEST:
645 	case TCODE_WRITE_BLOCK_REQUEST:
646 		return 0;
647 
648 	case TCODE_READ_QUADLET_REQUEST:
649 		return 4;
650 
651 	case TCODE_READ_BLOCK_REQUEST:
652 		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
653 		return data_length;
654 
655 	case TCODE_LOCK_REQUEST:
656 		ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
657 		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
658 		switch (ext_tcode) {
659 		case EXTCODE_FETCH_ADD:
660 		case EXTCODE_LITTLE_ADD:
661 			return data_length;
662 		default:
663 			return data_length / 2;
664 		}
665 
666 	default:
667 		WARN(1, "wrong tcode %d\n", tcode);
668 		return 0;
669 	}
670 }
671 
fw_fill_response(struct fw_packet * response,u32 * request_header,int rcode,void * payload,size_t length)672 void fw_fill_response(struct fw_packet *response, u32 *request_header,
673 		      int rcode, void *payload, size_t length)
674 {
675 	int tcode, tlabel, extended_tcode, source, destination;
676 
677 	tcode          = HEADER_GET_TCODE(request_header[0]);
678 	tlabel         = HEADER_GET_TLABEL(request_header[0]);
679 	source         = HEADER_GET_DESTINATION(request_header[0]);
680 	destination    = HEADER_GET_SOURCE(request_header[1]);
681 	extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
682 
683 	response->header[0] =
684 		HEADER_RETRY(RETRY_1) |
685 		HEADER_TLABEL(tlabel) |
686 		HEADER_DESTINATION(destination);
687 	response->header[1] =
688 		HEADER_SOURCE(source) |
689 		HEADER_RCODE(rcode);
690 	response->header[2] = 0;
691 
692 	switch (tcode) {
693 	case TCODE_WRITE_QUADLET_REQUEST:
694 	case TCODE_WRITE_BLOCK_REQUEST:
695 		response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
696 		response->header_length = 12;
697 		response->payload_length = 0;
698 		break;
699 
700 	case TCODE_READ_QUADLET_REQUEST:
701 		response->header[0] |=
702 			HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
703 		if (payload != NULL)
704 			response->header[3] = *(u32 *)payload;
705 		else
706 			response->header[3] = 0;
707 		response->header_length = 16;
708 		response->payload_length = 0;
709 		break;
710 
711 	case TCODE_READ_BLOCK_REQUEST:
712 	case TCODE_LOCK_REQUEST:
713 		response->header[0] |= HEADER_TCODE(tcode + 2);
714 		response->header[3] =
715 			HEADER_DATA_LENGTH(length) |
716 			HEADER_EXTENDED_TCODE(extended_tcode);
717 		response->header_length = 16;
718 		response->payload = payload;
719 		response->payload_length = length;
720 		break;
721 
722 	default:
723 		WARN(1, "wrong tcode %d\n", tcode);
724 	}
725 
726 	response->payload_mapped = false;
727 }
728 EXPORT_SYMBOL(fw_fill_response);
729 
compute_split_timeout_timestamp(struct fw_card * card,u32 request_timestamp)730 static u32 compute_split_timeout_timestamp(struct fw_card *card,
731 					   u32 request_timestamp)
732 {
733 	unsigned int cycles;
734 	u32 timestamp;
735 
736 	cycles = card->split_timeout_cycles;
737 	cycles += request_timestamp & 0x1fff;
738 
739 	timestamp = request_timestamp & ~0x1fff;
740 	timestamp += (cycles / 8000) << 13;
741 	timestamp |= cycles % 8000;
742 
743 	return timestamp;
744 }
745 
allocate_request(struct fw_card * card,struct fw_packet * p)746 static struct fw_request *allocate_request(struct fw_card *card,
747 					   struct fw_packet *p)
748 {
749 	struct fw_request *request;
750 	u32 *data, length;
751 	int request_tcode;
752 
753 	request_tcode = HEADER_GET_TCODE(p->header[0]);
754 	switch (request_tcode) {
755 	case TCODE_WRITE_QUADLET_REQUEST:
756 		data = &p->header[3];
757 		length = 4;
758 		break;
759 
760 	case TCODE_WRITE_BLOCK_REQUEST:
761 	case TCODE_LOCK_REQUEST:
762 		data = p->payload;
763 		length = HEADER_GET_DATA_LENGTH(p->header[3]);
764 		break;
765 
766 	case TCODE_READ_QUADLET_REQUEST:
767 		data = NULL;
768 		length = 4;
769 		break;
770 
771 	case TCODE_READ_BLOCK_REQUEST:
772 		data = NULL;
773 		length = HEADER_GET_DATA_LENGTH(p->header[3]);
774 		break;
775 
776 	default:
777 		fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
778 			 p->header[0], p->header[1], p->header[2]);
779 		return NULL;
780 	}
781 
782 	request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
783 	if (request == NULL)
784 		return NULL;
785 
786 	request->response.speed = p->speed;
787 	request->response.timestamp =
788 			compute_split_timeout_timestamp(card, p->timestamp);
789 	request->response.generation = p->generation;
790 	request->response.ack = 0;
791 	request->response.callback = free_response_callback;
792 	request->ack = p->ack;
793 	request->timestamp = p->timestamp;
794 	request->length = length;
795 	if (data)
796 		memcpy(request->data, data, length);
797 
798 	memcpy(request->request_header, p->header, sizeof(p->header));
799 
800 	return request;
801 }
802 
fw_send_response(struct fw_card * card,struct fw_request * request,int rcode)803 void fw_send_response(struct fw_card *card,
804 		      struct fw_request *request, int rcode)
805 {
806 	if (WARN_ONCE(!request, "invalid for FCP address handlers"))
807 		return;
808 
809 	/* unified transaction or broadcast transaction: don't respond */
810 	if (request->ack != ACK_PENDING ||
811 	    HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
812 		kfree(request);
813 		return;
814 	}
815 
816 	if (rcode == RCODE_COMPLETE)
817 		fw_fill_response(&request->response, request->request_header,
818 				 rcode, request->data,
819 				 fw_get_response_length(request));
820 	else
821 		fw_fill_response(&request->response, request->request_header,
822 				 rcode, NULL, 0);
823 
824 	card->driver->send_response(card, &request->response);
825 }
826 EXPORT_SYMBOL(fw_send_response);
827 
828 /**
829  * fw_get_request_speed() - returns speed at which the @request was received
830  * @request: firewire request data
831  */
fw_get_request_speed(struct fw_request * request)832 int fw_get_request_speed(struct fw_request *request)
833 {
834 	return request->response.speed;
835 }
836 EXPORT_SYMBOL(fw_get_request_speed);
837 
838 /**
839  * fw_request_get_timestamp: Get timestamp of the request.
840  * @request: The opaque pointer to request structure.
841  *
842  * Get timestamp when 1394 OHCI controller receives the asynchronous request subaction. The
843  * timestamp consists of the low order 3 bits of second field and the full 13 bits of count
844  * field of isochronous cycle time register.
845  *
846  * Returns: timestamp of the request.
847  */
fw_request_get_timestamp(const struct fw_request * request)848 u32 fw_request_get_timestamp(const struct fw_request *request)
849 {
850 	return request->timestamp;
851 }
852 EXPORT_SYMBOL_GPL(fw_request_get_timestamp);
853 
handle_exclusive_region_request(struct fw_card * card,struct fw_packet * p,struct fw_request * request,unsigned long long offset)854 static void handle_exclusive_region_request(struct fw_card *card,
855 					    struct fw_packet *p,
856 					    struct fw_request *request,
857 					    unsigned long long offset)
858 {
859 	struct fw_address_handler *handler;
860 	int tcode, destination, source;
861 
862 	destination = HEADER_GET_DESTINATION(p->header[0]);
863 	source      = HEADER_GET_SOURCE(p->header[1]);
864 	tcode       = HEADER_GET_TCODE(p->header[0]);
865 	if (tcode == TCODE_LOCK_REQUEST)
866 		tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
867 
868 	rcu_read_lock();
869 	handler = lookup_enclosing_address_handler(&address_handler_list,
870 						   offset, request->length);
871 	if (handler)
872 		handler->address_callback(card, request,
873 					  tcode, destination, source,
874 					  p->generation, offset,
875 					  request->data, request->length,
876 					  handler->callback_data);
877 	rcu_read_unlock();
878 
879 	if (!handler)
880 		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
881 }
882 
handle_fcp_region_request(struct fw_card * card,struct fw_packet * p,struct fw_request * request,unsigned long long offset)883 static void handle_fcp_region_request(struct fw_card *card,
884 				      struct fw_packet *p,
885 				      struct fw_request *request,
886 				      unsigned long long offset)
887 {
888 	struct fw_address_handler *handler;
889 	int tcode, destination, source;
890 
891 	if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
892 	     offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
893 	    request->length > 0x200) {
894 		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
895 
896 		return;
897 	}
898 
899 	tcode       = HEADER_GET_TCODE(p->header[0]);
900 	destination = HEADER_GET_DESTINATION(p->header[0]);
901 	source      = HEADER_GET_SOURCE(p->header[1]);
902 
903 	if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
904 	    tcode != TCODE_WRITE_BLOCK_REQUEST) {
905 		fw_send_response(card, request, RCODE_TYPE_ERROR);
906 
907 		return;
908 	}
909 
910 	rcu_read_lock();
911 	list_for_each_entry_rcu(handler, &address_handler_list, link) {
912 		if (is_enclosing_handler(handler, offset, request->length))
913 			handler->address_callback(card, NULL, tcode,
914 						  destination, source,
915 						  p->generation, offset,
916 						  request->data,
917 						  request->length,
918 						  handler->callback_data);
919 	}
920 	rcu_read_unlock();
921 
922 	fw_send_response(card, request, RCODE_COMPLETE);
923 }
924 
fw_core_handle_request(struct fw_card * card,struct fw_packet * p)925 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
926 {
927 	struct fw_request *request;
928 	unsigned long long offset;
929 
930 	if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
931 		return;
932 
933 	if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
934 		fw_cdev_handle_phy_packet(card, p);
935 		return;
936 	}
937 
938 	request = allocate_request(card, p);
939 	if (request == NULL) {
940 		/* FIXME: send statically allocated busy packet. */
941 		return;
942 	}
943 
944 	offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
945 		p->header[2];
946 
947 	if (!is_in_fcp_region(offset, request->length))
948 		handle_exclusive_region_request(card, p, request, offset);
949 	else
950 		handle_fcp_region_request(card, p, request, offset);
951 
952 }
953 EXPORT_SYMBOL(fw_core_handle_request);
954 
fw_core_handle_response(struct fw_card * card,struct fw_packet * p)955 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
956 {
957 	struct fw_transaction *t = NULL, *iter;
958 	unsigned long flags;
959 	u32 *data;
960 	size_t data_length;
961 	int tcode, tlabel, source, rcode;
962 
963 	tcode	= HEADER_GET_TCODE(p->header[0]);
964 	tlabel	= HEADER_GET_TLABEL(p->header[0]);
965 	source	= HEADER_GET_SOURCE(p->header[1]);
966 	rcode	= HEADER_GET_RCODE(p->header[1]);
967 
968 	spin_lock_irqsave(&card->lock, flags);
969 	list_for_each_entry(iter, &card->transaction_list, link) {
970 		if (iter->node_id == source && iter->tlabel == tlabel) {
971 			if (!try_cancel_split_timeout(iter)) {
972 				spin_unlock_irqrestore(&card->lock, flags);
973 				goto timed_out;
974 			}
975 			list_del_init(&iter->link);
976 			card->tlabel_mask &= ~(1ULL << iter->tlabel);
977 			t = iter;
978 			break;
979 		}
980 	}
981 	spin_unlock_irqrestore(&card->lock, flags);
982 
983 	if (!t) {
984  timed_out:
985 		fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
986 			  source, tlabel);
987 		return;
988 	}
989 
990 	/*
991 	 * FIXME: sanity check packet, is length correct, does tcodes
992 	 * and addresses match.
993 	 */
994 
995 	switch (tcode) {
996 	case TCODE_READ_QUADLET_RESPONSE:
997 		data = (u32 *) &p->header[3];
998 		data_length = 4;
999 		break;
1000 
1001 	case TCODE_WRITE_RESPONSE:
1002 		data = NULL;
1003 		data_length = 0;
1004 		break;
1005 
1006 	case TCODE_READ_BLOCK_RESPONSE:
1007 	case TCODE_LOCK_RESPONSE:
1008 		data = p->payload;
1009 		data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
1010 		break;
1011 
1012 	default:
1013 		/* Should never happen, this is just to shut up gcc. */
1014 		data = NULL;
1015 		data_length = 0;
1016 		break;
1017 	}
1018 
1019 	/*
1020 	 * The response handler may be executed while the request handler
1021 	 * is still pending.  Cancel the request handler.
1022 	 */
1023 	card->driver->cancel_packet(card, &t->packet);
1024 
1025 	t->callback(card, rcode, data, data_length, t->callback_data);
1026 }
1027 EXPORT_SYMBOL(fw_core_handle_response);
1028 
1029 /**
1030  * fw_rcode_string - convert a firewire result code to an error description
1031  * @rcode: the result code
1032  */
fw_rcode_string(int rcode)1033 const char *fw_rcode_string(int rcode)
1034 {
1035 	static const char *const names[] = {
1036 		[RCODE_COMPLETE]       = "no error",
1037 		[RCODE_CONFLICT_ERROR] = "conflict error",
1038 		[RCODE_DATA_ERROR]     = "data error",
1039 		[RCODE_TYPE_ERROR]     = "type error",
1040 		[RCODE_ADDRESS_ERROR]  = "address error",
1041 		[RCODE_SEND_ERROR]     = "send error",
1042 		[RCODE_CANCELLED]      = "timeout",
1043 		[RCODE_BUSY]           = "busy",
1044 		[RCODE_GENERATION]     = "bus reset",
1045 		[RCODE_NO_ACK]         = "no ack",
1046 	};
1047 
1048 	if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1049 		return names[rcode];
1050 	else
1051 		return "unknown";
1052 }
1053 EXPORT_SYMBOL(fw_rcode_string);
1054 
1055 static const struct fw_address_region topology_map_region =
1056 	{ .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1057 	  .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1058 
handle_topology_map(struct fw_card * card,struct fw_request * request,int tcode,int destination,int source,int generation,unsigned long long offset,void * payload,size_t length,void * callback_data)1059 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1060 		int tcode, int destination, int source, int generation,
1061 		unsigned long long offset, void *payload, size_t length,
1062 		void *callback_data)
1063 {
1064 	int start;
1065 
1066 	if (!TCODE_IS_READ_REQUEST(tcode)) {
1067 		fw_send_response(card, request, RCODE_TYPE_ERROR);
1068 		return;
1069 	}
1070 
1071 	if ((offset & 3) > 0 || (length & 3) > 0) {
1072 		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1073 		return;
1074 	}
1075 
1076 	start = (offset - topology_map_region.start) / 4;
1077 	memcpy(payload, &card->topology_map[start], length);
1078 
1079 	fw_send_response(card, request, RCODE_COMPLETE);
1080 }
1081 
1082 static struct fw_address_handler topology_map = {
1083 	.length			= 0x400,
1084 	.address_callback	= handle_topology_map,
1085 };
1086 
1087 static const struct fw_address_region registers_region =
1088 	{ .start = CSR_REGISTER_BASE,
1089 	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1090 
update_split_timeout(struct fw_card * card)1091 static void update_split_timeout(struct fw_card *card)
1092 {
1093 	unsigned int cycles;
1094 
1095 	cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1096 
1097 	/* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1098 	cycles = clamp(cycles, 800u, 3u * 8000u);
1099 
1100 	card->split_timeout_cycles = cycles;
1101 	card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1102 }
1103 
handle_registers(struct fw_card * card,struct fw_request * request,int tcode,int destination,int source,int generation,unsigned long long offset,void * payload,size_t length,void * callback_data)1104 static void handle_registers(struct fw_card *card, struct fw_request *request,
1105 		int tcode, int destination, int source, int generation,
1106 		unsigned long long offset, void *payload, size_t length,
1107 		void *callback_data)
1108 {
1109 	int reg = offset & ~CSR_REGISTER_BASE;
1110 	__be32 *data = payload;
1111 	int rcode = RCODE_COMPLETE;
1112 	unsigned long flags;
1113 
1114 	switch (reg) {
1115 	case CSR_PRIORITY_BUDGET:
1116 		if (!card->priority_budget_implemented) {
1117 			rcode = RCODE_ADDRESS_ERROR;
1118 			break;
1119 		}
1120 		fallthrough;
1121 
1122 	case CSR_NODE_IDS:
1123 		/*
1124 		 * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1125 		 * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1126 		 */
1127 		fallthrough;
1128 
1129 	case CSR_STATE_CLEAR:
1130 	case CSR_STATE_SET:
1131 	case CSR_CYCLE_TIME:
1132 	case CSR_BUS_TIME:
1133 	case CSR_BUSY_TIMEOUT:
1134 		if (tcode == TCODE_READ_QUADLET_REQUEST)
1135 			*data = cpu_to_be32(card->driver->read_csr(card, reg));
1136 		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1137 			card->driver->write_csr(card, reg, be32_to_cpu(*data));
1138 		else
1139 			rcode = RCODE_TYPE_ERROR;
1140 		break;
1141 
1142 	case CSR_RESET_START:
1143 		if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1144 			card->driver->write_csr(card, CSR_STATE_CLEAR,
1145 						CSR_STATE_BIT_ABDICATE);
1146 		else
1147 			rcode = RCODE_TYPE_ERROR;
1148 		break;
1149 
1150 	case CSR_SPLIT_TIMEOUT_HI:
1151 		if (tcode == TCODE_READ_QUADLET_REQUEST) {
1152 			*data = cpu_to_be32(card->split_timeout_hi);
1153 		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1154 			spin_lock_irqsave(&card->lock, flags);
1155 			card->split_timeout_hi = be32_to_cpu(*data) & 7;
1156 			update_split_timeout(card);
1157 			spin_unlock_irqrestore(&card->lock, flags);
1158 		} else {
1159 			rcode = RCODE_TYPE_ERROR;
1160 		}
1161 		break;
1162 
1163 	case CSR_SPLIT_TIMEOUT_LO:
1164 		if (tcode == TCODE_READ_QUADLET_REQUEST) {
1165 			*data = cpu_to_be32(card->split_timeout_lo);
1166 		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1167 			spin_lock_irqsave(&card->lock, flags);
1168 			card->split_timeout_lo =
1169 					be32_to_cpu(*data) & 0xfff80000;
1170 			update_split_timeout(card);
1171 			spin_unlock_irqrestore(&card->lock, flags);
1172 		} else {
1173 			rcode = RCODE_TYPE_ERROR;
1174 		}
1175 		break;
1176 
1177 	case CSR_MAINT_UTILITY:
1178 		if (tcode == TCODE_READ_QUADLET_REQUEST)
1179 			*data = card->maint_utility_register;
1180 		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1181 			card->maint_utility_register = *data;
1182 		else
1183 			rcode = RCODE_TYPE_ERROR;
1184 		break;
1185 
1186 	case CSR_BROADCAST_CHANNEL:
1187 		if (tcode == TCODE_READ_QUADLET_REQUEST)
1188 			*data = cpu_to_be32(card->broadcast_channel);
1189 		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1190 			card->broadcast_channel =
1191 			    (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1192 			    BROADCAST_CHANNEL_INITIAL;
1193 		else
1194 			rcode = RCODE_TYPE_ERROR;
1195 		break;
1196 
1197 	case CSR_BUS_MANAGER_ID:
1198 	case CSR_BANDWIDTH_AVAILABLE:
1199 	case CSR_CHANNELS_AVAILABLE_HI:
1200 	case CSR_CHANNELS_AVAILABLE_LO:
1201 		/*
1202 		 * FIXME: these are handled by the OHCI hardware and
1203 		 * the stack never sees these request. If we add
1204 		 * support for a new type of controller that doesn't
1205 		 * handle this in hardware we need to deal with these
1206 		 * transactions.
1207 		 */
1208 		BUG();
1209 		break;
1210 
1211 	default:
1212 		rcode = RCODE_ADDRESS_ERROR;
1213 		break;
1214 	}
1215 
1216 	fw_send_response(card, request, rcode);
1217 }
1218 
1219 static struct fw_address_handler registers = {
1220 	.length			= 0x400,
1221 	.address_callback	= handle_registers,
1222 };
1223 
handle_low_memory(struct fw_card * card,struct fw_request * request,int tcode,int destination,int source,int generation,unsigned long long offset,void * payload,size_t length,void * callback_data)1224 static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1225 		int tcode, int destination, int source, int generation,
1226 		unsigned long long offset, void *payload, size_t length,
1227 		void *callback_data)
1228 {
1229 	/*
1230 	 * This catches requests not handled by the physical DMA unit,
1231 	 * i.e., wrong transaction types or unauthorized source nodes.
1232 	 */
1233 	fw_send_response(card, request, RCODE_TYPE_ERROR);
1234 }
1235 
1236 static struct fw_address_handler low_memory = {
1237 	.length			= FW_MAX_PHYSICAL_RANGE,
1238 	.address_callback	= handle_low_memory,
1239 };
1240 
1241 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1242 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1243 MODULE_LICENSE("GPL");
1244 
1245 static const u32 vendor_textual_descriptor[] = {
1246 	/* textual descriptor leaf () */
1247 	0x00060000,
1248 	0x00000000,
1249 	0x00000000,
1250 	0x4c696e75,		/* L i n u */
1251 	0x78204669,		/* x   F i */
1252 	0x72657769,		/* r e w i */
1253 	0x72650000,		/* r e     */
1254 };
1255 
1256 static const u32 model_textual_descriptor[] = {
1257 	/* model descriptor leaf () */
1258 	0x00030000,
1259 	0x00000000,
1260 	0x00000000,
1261 	0x4a756a75,		/* J u j u */
1262 };
1263 
1264 static struct fw_descriptor vendor_id_descriptor = {
1265 	.length = ARRAY_SIZE(vendor_textual_descriptor),
1266 	.immediate = 0x03001f11,
1267 	.key = 0x81000000,
1268 	.data = vendor_textual_descriptor,
1269 };
1270 
1271 static struct fw_descriptor model_id_descriptor = {
1272 	.length = ARRAY_SIZE(model_textual_descriptor),
1273 	.immediate = 0x17023901,
1274 	.key = 0x81000000,
1275 	.data = model_textual_descriptor,
1276 };
1277 
fw_core_init(void)1278 static int __init fw_core_init(void)
1279 {
1280 	int ret;
1281 
1282 	fw_workqueue = alloc_workqueue("firewire", WQ_MEM_RECLAIM, 0);
1283 	if (!fw_workqueue)
1284 		return -ENOMEM;
1285 
1286 	ret = bus_register(&fw_bus_type);
1287 	if (ret < 0) {
1288 		destroy_workqueue(fw_workqueue);
1289 		return ret;
1290 	}
1291 
1292 	fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1293 	if (fw_cdev_major < 0) {
1294 		bus_unregister(&fw_bus_type);
1295 		destroy_workqueue(fw_workqueue);
1296 		return fw_cdev_major;
1297 	}
1298 
1299 	fw_core_add_address_handler(&topology_map, &topology_map_region);
1300 	fw_core_add_address_handler(&registers, &registers_region);
1301 	fw_core_add_address_handler(&low_memory, &low_memory_region);
1302 	fw_core_add_descriptor(&vendor_id_descriptor);
1303 	fw_core_add_descriptor(&model_id_descriptor);
1304 
1305 	return 0;
1306 }
1307 
fw_core_cleanup(void)1308 static void __exit fw_core_cleanup(void)
1309 {
1310 	unregister_chrdev(fw_cdev_major, "firewire");
1311 	bus_unregister(&fw_bus_type);
1312 	destroy_workqueue(fw_workqueue);
1313 	idr_destroy(&fw_device_idr);
1314 }
1315 
1316 module_init(fw_core_init);
1317 module_exit(fw_core_cleanup);
1318