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v6.2
   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 */
  65static 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
  73static 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 */
 107int 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}
 126EXPORT_SYMBOL(fw_cancel_transaction);
 127
 128static 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
 146static 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
 
 
 165static 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
 199static 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
 273static 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 */
 338void 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}
 380EXPORT_SYMBOL(fw_send_request);
 381
 382struct transaction_callback_data {
 383	struct completion done;
 384	void *payload;
 385	int rcode;
 386};
 387
 388static 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 */
 415int 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}
 432EXPORT_SYMBOL(fw_run_transaction);
 433
 434static DEFINE_MUTEX(phy_config_mutex);
 435static DECLARE_COMPLETION(phy_config_done);
 436
 437static void transmit_phy_packet_callback(struct fw_packet *packet,
 438					 struct fw_card *card, int status)
 439{
 440	complete(&phy_config_done);
 441}
 442
 443static 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
 451void 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
 484static 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
 498static 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
 505static 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
 518static DEFINE_SPINLOCK(address_handler_list_lock);
 519static LIST_HEAD(address_handler_list);
 520
 521const struct fw_address_region fw_high_memory_region =
 522	{ .start = FW_MAX_PHYSICAL_RANGE, .end = 0xffffe0000000ULL, };
 523EXPORT_SYMBOL(fw_high_memory_region);
 524
 525static const struct fw_address_region low_memory_region =
 526	{ .start = 0x000000000000ULL, .end = FW_MAX_PHYSICAL_RANGE, };
 527
 528#if 0
 529const struct fw_address_region fw_private_region =
 530	{ .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 531const struct fw_address_region fw_csr_region =
 532	{ .start = CSR_REGISTER_BASE,
 533	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 534const struct fw_address_region fw_unit_space_region =
 535	{ .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 536#endif  /*  0  */
 537
 538static 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 */
 563int 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}
 599EXPORT_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 */
 610void 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}
 617EXPORT_SYMBOL(fw_core_remove_address_handler);
 618
 619struct 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 628static 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
 637int 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
 672void 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}
 728EXPORT_SYMBOL(fw_fill_response);
 729
 730static 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
 746static 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
 
 
 
 
 
 
 
 
 
 803void 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}
 826EXPORT_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 */
 832int fw_get_request_speed(struct fw_request *request)
 833{
 834	return request->response.speed;
 835}
 836EXPORT_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 */
 848u32 fw_request_get_timestamp(const struct fw_request *request)
 849{
 850	return request->timestamp;
 851}
 852EXPORT_SYMBOL_GPL(fw_request_get_timestamp);
 853
 854static 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
 883static 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
 925void 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}
 953EXPORT_SYMBOL(fw_core_handle_request);
 954
 955void 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}
1027EXPORT_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 */
1033const 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}
1053EXPORT_SYMBOL(fw_rcode_string);
1054
1055static 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
1059static 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
1082static struct fw_address_handler topology_map = {
1083	.length			= 0x400,
1084	.address_callback	= handle_topology_map,
1085};
1086
1087static const struct fw_address_region registers_region =
1088	{ .start = CSR_REGISTER_BASE,
1089	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1090
1091static 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
1104static 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
1219static struct fw_address_handler registers = {
1220	.length			= 0x400,
1221	.address_callback	= handle_registers,
1222};
1223
1224static 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
1236static struct fw_address_handler low_memory = {
1237	.length			= FW_MAX_PHYSICAL_RANGE,
1238	.address_callback	= handle_low_memory,
1239};
1240
1241MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1242MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1243MODULE_LICENSE("GPL");
1244
1245static 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
1256static const u32 model_textual_descriptor[] = {
1257	/* model descriptor leaf () */
1258	0x00030000,
1259	0x00000000,
1260	0x00000000,
1261	0x4a756a75,		/* J u j u */
1262};
1263
1264static 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
1271static 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
1278static 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
1308static 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
1316module_init(fw_core_init);
1317module_exit(fw_core_cleanup);
v6.8
   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 */
  65static 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
  73static int close_transaction(struct fw_transaction *transaction, struct fw_card *card, int rcode,
  74			     u32 response_tstamp)
  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		if (!t->with_tstamp) {
  96			t->callback.without_tstamp(card, rcode, NULL, 0, t->callback_data);
  97		} else {
  98			t->callback.with_tstamp(card, rcode, t->packet.timestamp, response_tstamp,
  99						NULL, 0, t->callback_data);
 100		}
 101		return 0;
 102	}
 103
 104 timed_out:
 105	return -ENOENT;
 106}
 107
 108/*
 109 * Only valid for transactions that are potentially pending (ie have
 110 * been sent).
 111 */
 112int fw_cancel_transaction(struct fw_card *card,
 113			  struct fw_transaction *transaction)
 114{
 115	u32 tstamp;
 116
 117	/*
 118	 * Cancel the packet transmission if it's still queued.  That
 119	 * will call the packet transmission callback which cancels
 120	 * the transaction.
 121	 */
 122
 123	if (card->driver->cancel_packet(card, &transaction->packet) == 0)
 124		return 0;
 125
 126	/*
 127	 * If the request packet has already been sent, we need to see
 128	 * if the transaction is still pending and remove it in that case.
 129	 */
 130
 131	if (transaction->packet.ack == 0) {
 132		// The timestamp is reused since it was just read now.
 133		tstamp = transaction->packet.timestamp;
 134	} else {
 135		u32 curr_cycle_time = 0;
 136
 137		(void)fw_card_read_cycle_time(card, &curr_cycle_time);
 138		tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time);
 139	}
 140
 141	return close_transaction(transaction, card, RCODE_CANCELLED, tstamp);
 142}
 143EXPORT_SYMBOL(fw_cancel_transaction);
 144
 145static void split_transaction_timeout_callback(struct timer_list *timer)
 146{
 147	struct fw_transaction *t = from_timer(t, timer, split_timeout_timer);
 148	struct fw_card *card = t->card;
 149	unsigned long flags;
 150
 151	spin_lock_irqsave(&card->lock, flags);
 152	if (list_empty(&t->link)) {
 153		spin_unlock_irqrestore(&card->lock, flags);
 154		return;
 155	}
 156	list_del(&t->link);
 157	card->tlabel_mask &= ~(1ULL << t->tlabel);
 158	spin_unlock_irqrestore(&card->lock, flags);
 159
 160	if (!t->with_tstamp) {
 161		t->callback.without_tstamp(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 162	} else {
 163		t->callback.with_tstamp(card, RCODE_CANCELLED, t->packet.timestamp,
 164					t->split_timeout_cycle, NULL, 0, t->callback_data);
 165	}
 166}
 167
 168static void start_split_transaction_timeout(struct fw_transaction *t,
 169					    struct fw_card *card)
 170{
 171	unsigned long flags;
 172
 173	spin_lock_irqsave(&card->lock, flags);
 174
 175	if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
 176		spin_unlock_irqrestore(&card->lock, flags);
 177		return;
 178	}
 179
 180	t->is_split_transaction = true;
 181	mod_timer(&t->split_timeout_timer,
 182		  jiffies + card->split_timeout_jiffies);
 183
 184	spin_unlock_irqrestore(&card->lock, flags);
 185}
 186
 187static u32 compute_split_timeout_timestamp(struct fw_card *card, u32 request_timestamp);
 188
 189static void transmit_complete_callback(struct fw_packet *packet,
 190				       struct fw_card *card, int status)
 191{
 192	struct fw_transaction *t =
 193	    container_of(packet, struct fw_transaction, packet);
 194
 195	switch (status) {
 196	case ACK_COMPLETE:
 197		close_transaction(t, card, RCODE_COMPLETE, packet->timestamp);
 198		break;
 199	case ACK_PENDING:
 200	{
 201		t->split_timeout_cycle =
 202			compute_split_timeout_timestamp(card, packet->timestamp) & 0xffff;
 203		start_split_transaction_timeout(t, card);
 204		break;
 205	}
 206	case ACK_BUSY_X:
 207	case ACK_BUSY_A:
 208	case ACK_BUSY_B:
 209		close_transaction(t, card, RCODE_BUSY, packet->timestamp);
 210		break;
 211	case ACK_DATA_ERROR:
 212		close_transaction(t, card, RCODE_DATA_ERROR, packet->timestamp);
 213		break;
 214	case ACK_TYPE_ERROR:
 215		close_transaction(t, card, RCODE_TYPE_ERROR, packet->timestamp);
 216		break;
 217	default:
 218		/*
 219		 * In this case the ack is really a juju specific
 220		 * rcode, so just forward that to the callback.
 221		 */
 222		close_transaction(t, card, status, packet->timestamp);
 223		break;
 224	}
 225}
 226
 227static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 228		int destination_id, int source_id, int generation, int speed,
 229		unsigned long long offset, void *payload, size_t length)
 230{
 231	int ext_tcode;
 232
 233	if (tcode == TCODE_STREAM_DATA) {
 234		packet->header[0] =
 235			HEADER_DATA_LENGTH(length) |
 236			destination_id |
 237			HEADER_TCODE(TCODE_STREAM_DATA);
 238		packet->header_length = 4;
 239		packet->payload = payload;
 240		packet->payload_length = length;
 241
 242		goto common;
 243	}
 244
 245	if (tcode > 0x10) {
 246		ext_tcode = tcode & ~0x10;
 247		tcode = TCODE_LOCK_REQUEST;
 248	} else
 249		ext_tcode = 0;
 250
 251	packet->header[0] =
 252		HEADER_RETRY(RETRY_X) |
 253		HEADER_TLABEL(tlabel) |
 254		HEADER_TCODE(tcode) |
 255		HEADER_DESTINATION(destination_id);
 256	packet->header[1] =
 257		HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
 258	packet->header[2] =
 259		offset;
 260
 261	switch (tcode) {
 262	case TCODE_WRITE_QUADLET_REQUEST:
 263		packet->header[3] = *(u32 *)payload;
 264		packet->header_length = 16;
 265		packet->payload_length = 0;
 266		break;
 267
 268	case TCODE_LOCK_REQUEST:
 269	case TCODE_WRITE_BLOCK_REQUEST:
 270		packet->header[3] =
 271			HEADER_DATA_LENGTH(length) |
 272			HEADER_EXTENDED_TCODE(ext_tcode);
 273		packet->header_length = 16;
 274		packet->payload = payload;
 275		packet->payload_length = length;
 276		break;
 277
 278	case TCODE_READ_QUADLET_REQUEST:
 279		packet->header_length = 12;
 280		packet->payload_length = 0;
 281		break;
 282
 283	case TCODE_READ_BLOCK_REQUEST:
 284		packet->header[3] =
 285			HEADER_DATA_LENGTH(length) |
 286			HEADER_EXTENDED_TCODE(ext_tcode);
 287		packet->header_length = 16;
 288		packet->payload_length = 0;
 289		break;
 290
 291	default:
 292		WARN(1, "wrong tcode %d\n", tcode);
 293	}
 294 common:
 295	packet->speed = speed;
 296	packet->generation = generation;
 297	packet->ack = 0;
 298	packet->payload_mapped = false;
 299}
 300
 301static int allocate_tlabel(struct fw_card *card)
 302{
 303	int tlabel;
 304
 305	tlabel = card->current_tlabel;
 306	while (card->tlabel_mask & (1ULL << tlabel)) {
 307		tlabel = (tlabel + 1) & 0x3f;
 308		if (tlabel == card->current_tlabel)
 309			return -EBUSY;
 310	}
 311
 312	card->current_tlabel = (tlabel + 1) & 0x3f;
 313	card->tlabel_mask |= 1ULL << tlabel;
 314
 315	return tlabel;
 316}
 317
 318/**
 319 * __fw_send_request() - submit a request packet for transmission to generate callback for response
 320 *			 subaction with or without time stamp.
 321 * @card:		interface to send the request at
 322 * @t:			transaction instance to which the request belongs
 323 * @tcode:		transaction code
 324 * @destination_id:	destination node ID, consisting of bus_ID and phy_ID
 325 * @generation:		bus generation in which request and response are valid
 326 * @speed:		transmission speed
 327 * @offset:		48bit wide offset into destination's address space
 328 * @payload:		data payload for the request subaction
 329 * @length:		length of the payload, in bytes
 330 * @callback:		union of two functions whether to receive time stamp or not for response
 331 *			subaction.
 332 * @with_tstamp:	Whether to receive time stamp or not for response subaction.
 333 * @callback_data:	data to be passed to the transaction completion callback
 334 *
 335 * Submit a request packet into the asynchronous request transmission queue.
 336 * Can be called from atomic context.  If you prefer a blocking API, use
 337 * fw_run_transaction() in a context that can sleep.
 338 *
 339 * In case of lock requests, specify one of the firewire-core specific %TCODE_
 340 * constants instead of %TCODE_LOCK_REQUEST in @tcode.
 341 *
 342 * Make sure that the value in @destination_id is not older than the one in
 343 * @generation.  Otherwise the request is in danger to be sent to a wrong node.
 344 *
 345 * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
 346 * needs to synthesize @destination_id with fw_stream_packet_destination_id().
 347 * It will contain tag, channel, and sy data instead of a node ID then.
 348 *
 349 * The payload buffer at @data is going to be DMA-mapped except in case of
 350 * @length <= 8 or of local (loopback) requests.  Hence make sure that the
 351 * buffer complies with the restrictions of the streaming DMA mapping API.
 352 * @payload must not be freed before the @callback is called.
 353 *
 354 * In case of request types without payload, @data is NULL and @length is 0.
 355 *
 356 * After the transaction is completed successfully or unsuccessfully, the
 357 * @callback will be called.  Among its parameters is the response code which
 358 * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
 359 * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
 360 * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
 361 * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
 362 * generation, or missing ACK respectively.
 363 *
 364 * Note some timing corner cases:  fw_send_request() may complete much earlier
 365 * than when the request packet actually hits the wire.  On the other hand,
 366 * transaction completion and hence execution of @callback may happen even
 367 * before fw_send_request() returns.
 368 */
 369void __fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 370		int destination_id, int generation, int speed, unsigned long long offset,
 371		void *payload, size_t length, union fw_transaction_callback callback,
 372		bool with_tstamp, void *callback_data)
 373{
 374	unsigned long flags;
 375	int tlabel;
 376
 377	/*
 378	 * Allocate tlabel from the bitmap and put the transaction on
 379	 * the list while holding the card spinlock.
 380	 */
 381
 382	spin_lock_irqsave(&card->lock, flags);
 383
 384	tlabel = allocate_tlabel(card);
 385	if (tlabel < 0) {
 386		spin_unlock_irqrestore(&card->lock, flags);
 387		if (!with_tstamp) {
 388			callback.without_tstamp(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 389		} else {
 390			// Timestamping on behalf of hardware.
 391			u32 curr_cycle_time = 0;
 392			u32 tstamp;
 393
 394			(void)fw_card_read_cycle_time(card, &curr_cycle_time);
 395			tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time);
 396
 397			callback.with_tstamp(card, RCODE_SEND_ERROR, tstamp, tstamp, NULL, 0,
 398					     callback_data);
 399		}
 400		return;
 401	}
 402
 403	t->node_id = destination_id;
 404	t->tlabel = tlabel;
 405	t->card = card;
 406	t->is_split_transaction = false;
 407	timer_setup(&t->split_timeout_timer, split_transaction_timeout_callback, 0);
 
 408	t->callback = callback;
 409	t->with_tstamp = with_tstamp;
 410	t->callback_data = callback_data;
 411
 412	fw_fill_request(&t->packet, tcode, t->tlabel, destination_id, card->node_id, generation,
 
 413			speed, offset, payload, length);
 414	t->packet.callback = transmit_complete_callback;
 415
 416	list_add_tail(&t->link, &card->transaction_list);
 417
 418	spin_unlock_irqrestore(&card->lock, flags);
 419
 420	card->driver->send_request(card, &t->packet);
 421}
 422EXPORT_SYMBOL_GPL(__fw_send_request);
 423
 424struct transaction_callback_data {
 425	struct completion done;
 426	void *payload;
 427	int rcode;
 428};
 429
 430static void transaction_callback(struct fw_card *card, int rcode,
 431				 void *payload, size_t length, void *data)
 432{
 433	struct transaction_callback_data *d = data;
 434
 435	if (rcode == RCODE_COMPLETE)
 436		memcpy(d->payload, payload, length);
 437	d->rcode = rcode;
 438	complete(&d->done);
 439}
 440
 441/**
 442 * fw_run_transaction() - send request and sleep until transaction is completed
 443 * @card:		card interface for this request
 444 * @tcode:		transaction code
 445 * @destination_id:	destination node ID, consisting of bus_ID and phy_ID
 446 * @generation:		bus generation in which request and response are valid
 447 * @speed:		transmission speed
 448 * @offset:		48bit wide offset into destination's address space
 449 * @payload:		data payload for the request subaction
 450 * @length:		length of the payload, in bytes
 451 *
 452 * Returns the RCODE.  See fw_send_request() for parameter documentation.
 453 * Unlike fw_send_request(), @data points to the payload of the request or/and
 454 * to the payload of the response.  DMA mapping restrictions apply to outbound
 455 * request payloads of >= 8 bytes but not to inbound response payloads.
 456 */
 457int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 458		       int generation, int speed, unsigned long long offset,
 459		       void *payload, size_t length)
 460{
 461	struct transaction_callback_data d;
 462	struct fw_transaction t;
 463
 464	timer_setup_on_stack(&t.split_timeout_timer, NULL, 0);
 465	init_completion(&d.done);
 466	d.payload = payload;
 467	fw_send_request(card, &t, tcode, destination_id, generation, speed,
 468			offset, payload, length, transaction_callback, &d);
 469	wait_for_completion(&d.done);
 470	destroy_timer_on_stack(&t.split_timeout_timer);
 471
 472	return d.rcode;
 473}
 474EXPORT_SYMBOL(fw_run_transaction);
 475
 476static DEFINE_MUTEX(phy_config_mutex);
 477static DECLARE_COMPLETION(phy_config_done);
 478
 479static void transmit_phy_packet_callback(struct fw_packet *packet,
 480					 struct fw_card *card, int status)
 481{
 482	complete(&phy_config_done);
 483}
 484
 485static struct fw_packet phy_config_packet = {
 486	.header_length	= 12,
 487	.header[0]	= TCODE_LINK_INTERNAL << 4,
 488	.payload_length	= 0,
 489	.speed		= SCODE_100,
 490	.callback	= transmit_phy_packet_callback,
 491};
 492
 493void fw_send_phy_config(struct fw_card *card,
 494			int node_id, int generation, int gap_count)
 495{
 496	long timeout = DIV_ROUND_UP(HZ, 10);
 497	u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
 498
 499	if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
 500		data |= PHY_CONFIG_ROOT_ID(node_id);
 501
 502	if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
 503		gap_count = card->driver->read_phy_reg(card, 1);
 504		if (gap_count < 0)
 505			return;
 506
 507		gap_count &= 63;
 508		if (gap_count == 63)
 509			return;
 510	}
 511	data |= PHY_CONFIG_GAP_COUNT(gap_count);
 512
 513	mutex_lock(&phy_config_mutex);
 514
 515	phy_config_packet.header[1] = data;
 516	phy_config_packet.header[2] = ~data;
 517	phy_config_packet.generation = generation;
 518	reinit_completion(&phy_config_done);
 519
 520	card->driver->send_request(card, &phy_config_packet);
 521	wait_for_completion_timeout(&phy_config_done, timeout);
 522
 523	mutex_unlock(&phy_config_mutex);
 524}
 525
 526static struct fw_address_handler *lookup_overlapping_address_handler(
 527	struct list_head *list, unsigned long long offset, size_t length)
 528{
 529	struct fw_address_handler *handler;
 530
 531	list_for_each_entry_rcu(handler, list, link) {
 532		if (handler->offset < offset + length &&
 533		    offset < handler->offset + handler->length)
 534			return handler;
 535	}
 536
 537	return NULL;
 538}
 539
 540static bool is_enclosing_handler(struct fw_address_handler *handler,
 541				 unsigned long long offset, size_t length)
 542{
 543	return handler->offset <= offset &&
 544		offset + length <= handler->offset + handler->length;
 545}
 546
 547static struct fw_address_handler *lookup_enclosing_address_handler(
 548	struct list_head *list, unsigned long long offset, size_t length)
 549{
 550	struct fw_address_handler *handler;
 551
 552	list_for_each_entry_rcu(handler, list, link) {
 553		if (is_enclosing_handler(handler, offset, length))
 554			return handler;
 555	}
 556
 557	return NULL;
 558}
 559
 560static DEFINE_SPINLOCK(address_handler_list_lock);
 561static LIST_HEAD(address_handler_list);
 562
 563const struct fw_address_region fw_high_memory_region =
 564	{ .start = FW_MAX_PHYSICAL_RANGE, .end = 0xffffe0000000ULL, };
 565EXPORT_SYMBOL(fw_high_memory_region);
 566
 567static const struct fw_address_region low_memory_region =
 568	{ .start = 0x000000000000ULL, .end = FW_MAX_PHYSICAL_RANGE, };
 569
 570#if 0
 571const struct fw_address_region fw_private_region =
 572	{ .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 573const struct fw_address_region fw_csr_region =
 574	{ .start = CSR_REGISTER_BASE,
 575	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 576const struct fw_address_region fw_unit_space_region =
 577	{ .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 578#endif  /*  0  */
 579
 
 
 
 
 
 
 580/**
 581 * fw_core_add_address_handler() - register for incoming requests
 582 * @handler:	callback
 583 * @region:	region in the IEEE 1212 node space address range
 584 *
 585 * region->start, ->end, and handler->length have to be quadlet-aligned.
 586 *
 587 * When a request is received that falls within the specified address range,
 588 * the specified callback is invoked.  The parameters passed to the callback
 589 * give the details of the particular request.
 590 *
 591 * To be called in process context.
 592 * Return value:  0 on success, non-zero otherwise.
 593 *
 594 * The start offset of the handler's address region is determined by
 595 * fw_core_add_address_handler() and is returned in handler->offset.
 596 *
 597 * Address allocations are exclusive, except for the FCP registers.
 598 */
 599int fw_core_add_address_handler(struct fw_address_handler *handler,
 600				const struct fw_address_region *region)
 601{
 602	struct fw_address_handler *other;
 603	int ret = -EBUSY;
 604
 605	if (region->start & 0xffff000000000003ULL ||
 606	    region->start >= region->end ||
 607	    region->end   > 0x0001000000000000ULL ||
 608	    handler->length & 3 ||
 609	    handler->length == 0)
 610		return -EINVAL;
 611
 612	spin_lock(&address_handler_list_lock);
 613
 614	handler->offset = region->start;
 615	while (handler->offset + handler->length <= region->end) {
 616		if (is_in_fcp_region(handler->offset, handler->length))
 617			other = NULL;
 618		else
 619			other = lookup_overlapping_address_handler
 620					(&address_handler_list,
 621					 handler->offset, handler->length);
 622		if (other != NULL) {
 623			handler->offset += other->length;
 624		} else {
 625			list_add_tail_rcu(&handler->link, &address_handler_list);
 626			ret = 0;
 627			break;
 628		}
 629	}
 630
 631	spin_unlock(&address_handler_list_lock);
 632
 633	return ret;
 634}
 635EXPORT_SYMBOL(fw_core_add_address_handler);
 636
 637/**
 638 * fw_core_remove_address_handler() - unregister an address handler
 639 * @handler: callback
 640 *
 641 * To be called in process context.
 642 *
 643 * When fw_core_remove_address_handler() returns, @handler->callback() is
 644 * guaranteed to not run on any CPU anymore.
 645 */
 646void fw_core_remove_address_handler(struct fw_address_handler *handler)
 647{
 648	spin_lock(&address_handler_list_lock);
 649	list_del_rcu(&handler->link);
 650	spin_unlock(&address_handler_list_lock);
 651	synchronize_rcu();
 652}
 653EXPORT_SYMBOL(fw_core_remove_address_handler);
 654
 655struct fw_request {
 656	struct kref kref;
 657	struct fw_packet response;
 658	u32 request_header[4];
 659	int ack;
 660	u32 timestamp;
 661	u32 length;
 662	u32 data[];
 663};
 664
 665void fw_request_get(struct fw_request *request)
 666{
 667	kref_get(&request->kref);
 668}
 669
 670static void release_request(struct kref *kref)
 671{
 672	struct fw_request *request = container_of(kref, struct fw_request, kref);
 673
 674	kfree(request);
 675}
 676
 677void fw_request_put(struct fw_request *request)
 678{
 679	kref_put(&request->kref, release_request);
 680}
 681
 682static void free_response_callback(struct fw_packet *packet,
 683				   struct fw_card *card, int status)
 684{
 685	struct fw_request *request = container_of(packet, struct fw_request, response);
 686
 687	// Decrease the reference count since not at in-flight.
 688	fw_request_put(request);
 689
 690	// Decrease the reference count to release the object.
 691	fw_request_put(request);
 692}
 693
 694int fw_get_response_length(struct fw_request *r)
 695{
 696	int tcode, ext_tcode, data_length;
 697
 698	tcode = HEADER_GET_TCODE(r->request_header[0]);
 699
 700	switch (tcode) {
 701	case TCODE_WRITE_QUADLET_REQUEST:
 702	case TCODE_WRITE_BLOCK_REQUEST:
 703		return 0;
 704
 705	case TCODE_READ_QUADLET_REQUEST:
 706		return 4;
 707
 708	case TCODE_READ_BLOCK_REQUEST:
 709		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 710		return data_length;
 711
 712	case TCODE_LOCK_REQUEST:
 713		ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 714		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 715		switch (ext_tcode) {
 716		case EXTCODE_FETCH_ADD:
 717		case EXTCODE_LITTLE_ADD:
 718			return data_length;
 719		default:
 720			return data_length / 2;
 721		}
 722
 723	default:
 724		WARN(1, "wrong tcode %d\n", tcode);
 725		return 0;
 726	}
 727}
 728
 729void fw_fill_response(struct fw_packet *response, u32 *request_header,
 730		      int rcode, void *payload, size_t length)
 731{
 732	int tcode, tlabel, extended_tcode, source, destination;
 733
 734	tcode          = HEADER_GET_TCODE(request_header[0]);
 735	tlabel         = HEADER_GET_TLABEL(request_header[0]);
 736	source         = HEADER_GET_DESTINATION(request_header[0]);
 737	destination    = HEADER_GET_SOURCE(request_header[1]);
 738	extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 739
 740	response->header[0] =
 741		HEADER_RETRY(RETRY_1) |
 742		HEADER_TLABEL(tlabel) |
 743		HEADER_DESTINATION(destination);
 744	response->header[1] =
 745		HEADER_SOURCE(source) |
 746		HEADER_RCODE(rcode);
 747	response->header[2] = 0;
 748
 749	switch (tcode) {
 750	case TCODE_WRITE_QUADLET_REQUEST:
 751	case TCODE_WRITE_BLOCK_REQUEST:
 752		response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 753		response->header_length = 12;
 754		response->payload_length = 0;
 755		break;
 756
 757	case TCODE_READ_QUADLET_REQUEST:
 758		response->header[0] |=
 759			HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 760		if (payload != NULL)
 761			response->header[3] = *(u32 *)payload;
 762		else
 763			response->header[3] = 0;
 764		response->header_length = 16;
 765		response->payload_length = 0;
 766		break;
 767
 768	case TCODE_READ_BLOCK_REQUEST:
 769	case TCODE_LOCK_REQUEST:
 770		response->header[0] |= HEADER_TCODE(tcode + 2);
 771		response->header[3] =
 772			HEADER_DATA_LENGTH(length) |
 773			HEADER_EXTENDED_TCODE(extended_tcode);
 774		response->header_length = 16;
 775		response->payload = payload;
 776		response->payload_length = length;
 777		break;
 778
 779	default:
 780		WARN(1, "wrong tcode %d\n", tcode);
 781	}
 782
 783	response->payload_mapped = false;
 784}
 785EXPORT_SYMBOL(fw_fill_response);
 786
 787static u32 compute_split_timeout_timestamp(struct fw_card *card,
 788					   u32 request_timestamp)
 789{
 790	unsigned int cycles;
 791	u32 timestamp;
 792
 793	cycles = card->split_timeout_cycles;
 794	cycles += request_timestamp & 0x1fff;
 795
 796	timestamp = request_timestamp & ~0x1fff;
 797	timestamp += (cycles / 8000) << 13;
 798	timestamp |= cycles % 8000;
 799
 800	return timestamp;
 801}
 802
 803static struct fw_request *allocate_request(struct fw_card *card,
 804					   struct fw_packet *p)
 805{
 806	struct fw_request *request;
 807	u32 *data, length;
 808	int request_tcode;
 809
 810	request_tcode = HEADER_GET_TCODE(p->header[0]);
 811	switch (request_tcode) {
 812	case TCODE_WRITE_QUADLET_REQUEST:
 813		data = &p->header[3];
 814		length = 4;
 815		break;
 816
 817	case TCODE_WRITE_BLOCK_REQUEST:
 818	case TCODE_LOCK_REQUEST:
 819		data = p->payload;
 820		length = HEADER_GET_DATA_LENGTH(p->header[3]);
 821		break;
 822
 823	case TCODE_READ_QUADLET_REQUEST:
 824		data = NULL;
 825		length = 4;
 826		break;
 827
 828	case TCODE_READ_BLOCK_REQUEST:
 829		data = NULL;
 830		length = HEADER_GET_DATA_LENGTH(p->header[3]);
 831		break;
 832
 833	default:
 834		fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
 835			 p->header[0], p->header[1], p->header[2]);
 836		return NULL;
 837	}
 838
 839	request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 840	if (request == NULL)
 841		return NULL;
 842	kref_init(&request->kref);
 843
 844	request->response.speed = p->speed;
 845	request->response.timestamp =
 846			compute_split_timeout_timestamp(card, p->timestamp);
 847	request->response.generation = p->generation;
 848	request->response.ack = 0;
 849	request->response.callback = free_response_callback;
 850	request->ack = p->ack;
 851	request->timestamp = p->timestamp;
 852	request->length = length;
 853	if (data)
 854		memcpy(request->data, data, length);
 855
 856	memcpy(request->request_header, p->header, sizeof(p->header));
 857
 858	return request;
 859}
 860
 861/**
 862 * fw_send_response: - send response packet for asynchronous transaction.
 863 * @card:	interface to send the response at.
 864 * @request:	firewire request data for the transaction.
 865 * @rcode:	response code to send.
 866 *
 867 * Submit a response packet into the asynchronous response transmission queue. The @request
 868 * is going to be released when the transmission successfully finishes later.
 869 */
 870void fw_send_response(struct fw_card *card,
 871		      struct fw_request *request, int rcode)
 872{
 
 
 
 873	/* unified transaction or broadcast transaction: don't respond */
 874	if (request->ack != ACK_PENDING ||
 875	    HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 876		fw_request_put(request);
 877		return;
 878	}
 879
 880	if (rcode == RCODE_COMPLETE)
 881		fw_fill_response(&request->response, request->request_header,
 882				 rcode, request->data,
 883				 fw_get_response_length(request));
 884	else
 885		fw_fill_response(&request->response, request->request_header,
 886				 rcode, NULL, 0);
 887
 888	// Increase the reference count so that the object is kept during in-flight.
 889	fw_request_get(request);
 890
 891	card->driver->send_response(card, &request->response);
 892}
 893EXPORT_SYMBOL(fw_send_response);
 894
 895/**
 896 * fw_get_request_speed() - returns speed at which the @request was received
 897 * @request: firewire request data
 898 */
 899int fw_get_request_speed(struct fw_request *request)
 900{
 901	return request->response.speed;
 902}
 903EXPORT_SYMBOL(fw_get_request_speed);
 904
 905/**
 906 * fw_request_get_timestamp: Get timestamp of the request.
 907 * @request: The opaque pointer to request structure.
 908 *
 909 * Get timestamp when 1394 OHCI controller receives the asynchronous request subaction. The
 910 * timestamp consists of the low order 3 bits of second field and the full 13 bits of count
 911 * field of isochronous cycle time register.
 912 *
 913 * Returns: timestamp of the request.
 914 */
 915u32 fw_request_get_timestamp(const struct fw_request *request)
 916{
 917	return request->timestamp;
 918}
 919EXPORT_SYMBOL_GPL(fw_request_get_timestamp);
 920
 921static void handle_exclusive_region_request(struct fw_card *card,
 922					    struct fw_packet *p,
 923					    struct fw_request *request,
 924					    unsigned long long offset)
 925{
 926	struct fw_address_handler *handler;
 927	int tcode, destination, source;
 928
 929	destination = HEADER_GET_DESTINATION(p->header[0]);
 930	source      = HEADER_GET_SOURCE(p->header[1]);
 931	tcode       = HEADER_GET_TCODE(p->header[0]);
 932	if (tcode == TCODE_LOCK_REQUEST)
 933		tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 934
 935	rcu_read_lock();
 936	handler = lookup_enclosing_address_handler(&address_handler_list,
 937						   offset, request->length);
 938	if (handler)
 939		handler->address_callback(card, request,
 940					  tcode, destination, source,
 941					  p->generation, offset,
 942					  request->data, request->length,
 943					  handler->callback_data);
 944	rcu_read_unlock();
 945
 946	if (!handler)
 947		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 948}
 949
 950static void handle_fcp_region_request(struct fw_card *card,
 951				      struct fw_packet *p,
 952				      struct fw_request *request,
 953				      unsigned long long offset)
 954{
 955	struct fw_address_handler *handler;
 956	int tcode, destination, source;
 957
 958	if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 959	     offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
 960	    request->length > 0x200) {
 961		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 962
 963		return;
 964	}
 965
 966	tcode       = HEADER_GET_TCODE(p->header[0]);
 967	destination = HEADER_GET_DESTINATION(p->header[0]);
 968	source      = HEADER_GET_SOURCE(p->header[1]);
 969
 970	if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
 971	    tcode != TCODE_WRITE_BLOCK_REQUEST) {
 972		fw_send_response(card, request, RCODE_TYPE_ERROR);
 973
 974		return;
 975	}
 976
 977	rcu_read_lock();
 978	list_for_each_entry_rcu(handler, &address_handler_list, link) {
 979		if (is_enclosing_handler(handler, offset, request->length))
 980			handler->address_callback(card, request, tcode,
 981						  destination, source,
 982						  p->generation, offset,
 983						  request->data,
 984						  request->length,
 985						  handler->callback_data);
 986	}
 987	rcu_read_unlock();
 988
 989	fw_send_response(card, request, RCODE_COMPLETE);
 990}
 991
 992void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 993{
 994	struct fw_request *request;
 995	unsigned long long offset;
 996
 997	if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 998		return;
 999
1000	if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
1001		fw_cdev_handle_phy_packet(card, p);
1002		return;
1003	}
1004
1005	request = allocate_request(card, p);
1006	if (request == NULL) {
1007		/* FIXME: send statically allocated busy packet. */
1008		return;
1009	}
1010
1011	offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
1012		p->header[2];
1013
1014	if (!is_in_fcp_region(offset, request->length))
1015		handle_exclusive_region_request(card, p, request, offset);
1016	else
1017		handle_fcp_region_request(card, p, request, offset);
1018
1019}
1020EXPORT_SYMBOL(fw_core_handle_request);
1021
1022void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
1023{
1024	struct fw_transaction *t = NULL, *iter;
1025	unsigned long flags;
1026	u32 *data;
1027	size_t data_length;
1028	int tcode, tlabel, source, rcode;
1029
1030	tcode	= HEADER_GET_TCODE(p->header[0]);
1031	tlabel	= HEADER_GET_TLABEL(p->header[0]);
1032	source	= HEADER_GET_SOURCE(p->header[1]);
1033	rcode	= HEADER_GET_RCODE(p->header[1]);
1034
1035	spin_lock_irqsave(&card->lock, flags);
1036	list_for_each_entry(iter, &card->transaction_list, link) {
1037		if (iter->node_id == source && iter->tlabel == tlabel) {
1038			if (!try_cancel_split_timeout(iter)) {
1039				spin_unlock_irqrestore(&card->lock, flags);
1040				goto timed_out;
1041			}
1042			list_del_init(&iter->link);
1043			card->tlabel_mask &= ~(1ULL << iter->tlabel);
1044			t = iter;
1045			break;
1046		}
1047	}
1048	spin_unlock_irqrestore(&card->lock, flags);
1049
1050	if (!t) {
1051 timed_out:
1052		fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
1053			  source, tlabel);
1054		return;
1055	}
1056
1057	/*
1058	 * FIXME: sanity check packet, is length correct, does tcodes
1059	 * and addresses match.
1060	 */
1061
1062	switch (tcode) {
1063	case TCODE_READ_QUADLET_RESPONSE:
1064		data = (u32 *) &p->header[3];
1065		data_length = 4;
1066		break;
1067
1068	case TCODE_WRITE_RESPONSE:
1069		data = NULL;
1070		data_length = 0;
1071		break;
1072
1073	case TCODE_READ_BLOCK_RESPONSE:
1074	case TCODE_LOCK_RESPONSE:
1075		data = p->payload;
1076		data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
1077		break;
1078
1079	default:
1080		/* Should never happen, this is just to shut up gcc. */
1081		data = NULL;
1082		data_length = 0;
1083		break;
1084	}
1085
1086	/*
1087	 * The response handler may be executed while the request handler
1088	 * is still pending.  Cancel the request handler.
1089	 */
1090	card->driver->cancel_packet(card, &t->packet);
1091
1092	if (!t->with_tstamp) {
1093		t->callback.without_tstamp(card, rcode, data, data_length, t->callback_data);
1094	} else {
1095		t->callback.with_tstamp(card, rcode, t->packet.timestamp, p->timestamp, data,
1096					data_length, t->callback_data);
1097	}
1098}
1099EXPORT_SYMBOL(fw_core_handle_response);
1100
1101/**
1102 * fw_rcode_string - convert a firewire result code to an error description
1103 * @rcode: the result code
1104 */
1105const char *fw_rcode_string(int rcode)
1106{
1107	static const char *const names[] = {
1108		[RCODE_COMPLETE]       = "no error",
1109		[RCODE_CONFLICT_ERROR] = "conflict error",
1110		[RCODE_DATA_ERROR]     = "data error",
1111		[RCODE_TYPE_ERROR]     = "type error",
1112		[RCODE_ADDRESS_ERROR]  = "address error",
1113		[RCODE_SEND_ERROR]     = "send error",
1114		[RCODE_CANCELLED]      = "timeout",
1115		[RCODE_BUSY]           = "busy",
1116		[RCODE_GENERATION]     = "bus reset",
1117		[RCODE_NO_ACK]         = "no ack",
1118	};
1119
1120	if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1121		return names[rcode];
1122	else
1123		return "unknown";
1124}
1125EXPORT_SYMBOL(fw_rcode_string);
1126
1127static const struct fw_address_region topology_map_region =
1128	{ .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1129	  .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1130
1131static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1132		int tcode, int destination, int source, int generation,
1133		unsigned long long offset, void *payload, size_t length,
1134		void *callback_data)
1135{
1136	int start;
1137
1138	if (!TCODE_IS_READ_REQUEST(tcode)) {
1139		fw_send_response(card, request, RCODE_TYPE_ERROR);
1140		return;
1141	}
1142
1143	if ((offset & 3) > 0 || (length & 3) > 0) {
1144		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1145		return;
1146	}
1147
1148	start = (offset - topology_map_region.start) / 4;
1149	memcpy(payload, &card->topology_map[start], length);
1150
1151	fw_send_response(card, request, RCODE_COMPLETE);
1152}
1153
1154static struct fw_address_handler topology_map = {
1155	.length			= 0x400,
1156	.address_callback	= handle_topology_map,
1157};
1158
1159static const struct fw_address_region registers_region =
1160	{ .start = CSR_REGISTER_BASE,
1161	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1162
1163static void update_split_timeout(struct fw_card *card)
1164{
1165	unsigned int cycles;
1166
1167	cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1168
1169	/* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1170	cycles = clamp(cycles, 800u, 3u * 8000u);
1171
1172	card->split_timeout_cycles = cycles;
1173	card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1174}
1175
1176static void handle_registers(struct fw_card *card, struct fw_request *request,
1177		int tcode, int destination, int source, int generation,
1178		unsigned long long offset, void *payload, size_t length,
1179		void *callback_data)
1180{
1181	int reg = offset & ~CSR_REGISTER_BASE;
1182	__be32 *data = payload;
1183	int rcode = RCODE_COMPLETE;
1184	unsigned long flags;
1185
1186	switch (reg) {
1187	case CSR_PRIORITY_BUDGET:
1188		if (!card->priority_budget_implemented) {
1189			rcode = RCODE_ADDRESS_ERROR;
1190			break;
1191		}
1192		fallthrough;
1193
1194	case CSR_NODE_IDS:
1195		/*
1196		 * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1197		 * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1198		 */
1199		fallthrough;
1200
1201	case CSR_STATE_CLEAR:
1202	case CSR_STATE_SET:
1203	case CSR_CYCLE_TIME:
1204	case CSR_BUS_TIME:
1205	case CSR_BUSY_TIMEOUT:
1206		if (tcode == TCODE_READ_QUADLET_REQUEST)
1207			*data = cpu_to_be32(card->driver->read_csr(card, reg));
1208		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1209			card->driver->write_csr(card, reg, be32_to_cpu(*data));
1210		else
1211			rcode = RCODE_TYPE_ERROR;
1212		break;
1213
1214	case CSR_RESET_START:
1215		if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1216			card->driver->write_csr(card, CSR_STATE_CLEAR,
1217						CSR_STATE_BIT_ABDICATE);
1218		else
1219			rcode = RCODE_TYPE_ERROR;
1220		break;
1221
1222	case CSR_SPLIT_TIMEOUT_HI:
1223		if (tcode == TCODE_READ_QUADLET_REQUEST) {
1224			*data = cpu_to_be32(card->split_timeout_hi);
1225		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1226			spin_lock_irqsave(&card->lock, flags);
1227			card->split_timeout_hi = be32_to_cpu(*data) & 7;
1228			update_split_timeout(card);
1229			spin_unlock_irqrestore(&card->lock, flags);
1230		} else {
1231			rcode = RCODE_TYPE_ERROR;
1232		}
1233		break;
1234
1235	case CSR_SPLIT_TIMEOUT_LO:
1236		if (tcode == TCODE_READ_QUADLET_REQUEST) {
1237			*data = cpu_to_be32(card->split_timeout_lo);
1238		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1239			spin_lock_irqsave(&card->lock, flags);
1240			card->split_timeout_lo =
1241					be32_to_cpu(*data) & 0xfff80000;
1242			update_split_timeout(card);
1243			spin_unlock_irqrestore(&card->lock, flags);
1244		} else {
1245			rcode = RCODE_TYPE_ERROR;
1246		}
1247		break;
1248
1249	case CSR_MAINT_UTILITY:
1250		if (tcode == TCODE_READ_QUADLET_REQUEST)
1251			*data = card->maint_utility_register;
1252		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1253			card->maint_utility_register = *data;
1254		else
1255			rcode = RCODE_TYPE_ERROR;
1256		break;
1257
1258	case CSR_BROADCAST_CHANNEL:
1259		if (tcode == TCODE_READ_QUADLET_REQUEST)
1260			*data = cpu_to_be32(card->broadcast_channel);
1261		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1262			card->broadcast_channel =
1263			    (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1264			    BROADCAST_CHANNEL_INITIAL;
1265		else
1266			rcode = RCODE_TYPE_ERROR;
1267		break;
1268
1269	case CSR_BUS_MANAGER_ID:
1270	case CSR_BANDWIDTH_AVAILABLE:
1271	case CSR_CHANNELS_AVAILABLE_HI:
1272	case CSR_CHANNELS_AVAILABLE_LO:
1273		/*
1274		 * FIXME: these are handled by the OHCI hardware and
1275		 * the stack never sees these request. If we add
1276		 * support for a new type of controller that doesn't
1277		 * handle this in hardware we need to deal with these
1278		 * transactions.
1279		 */
1280		BUG();
1281		break;
1282
1283	default:
1284		rcode = RCODE_ADDRESS_ERROR;
1285		break;
1286	}
1287
1288	fw_send_response(card, request, rcode);
1289}
1290
1291static struct fw_address_handler registers = {
1292	.length			= 0x400,
1293	.address_callback	= handle_registers,
1294};
1295
1296static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1297		int tcode, int destination, int source, int generation,
1298		unsigned long long offset, void *payload, size_t length,
1299		void *callback_data)
1300{
1301	/*
1302	 * This catches requests not handled by the physical DMA unit,
1303	 * i.e., wrong transaction types or unauthorized source nodes.
1304	 */
1305	fw_send_response(card, request, RCODE_TYPE_ERROR);
1306}
1307
1308static struct fw_address_handler low_memory = {
1309	.length			= FW_MAX_PHYSICAL_RANGE,
1310	.address_callback	= handle_low_memory,
1311};
1312
1313MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1314MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1315MODULE_LICENSE("GPL");
1316
1317static const u32 vendor_textual_descriptor[] = {
1318	/* textual descriptor leaf () */
1319	0x00060000,
1320	0x00000000,
1321	0x00000000,
1322	0x4c696e75,		/* L i n u */
1323	0x78204669,		/* x   F i */
1324	0x72657769,		/* r e w i */
1325	0x72650000,		/* r e     */
1326};
1327
1328static const u32 model_textual_descriptor[] = {
1329	/* model descriptor leaf () */
1330	0x00030000,
1331	0x00000000,
1332	0x00000000,
1333	0x4a756a75,		/* J u j u */
1334};
1335
1336static struct fw_descriptor vendor_id_descriptor = {
1337	.length = ARRAY_SIZE(vendor_textual_descriptor),
1338	.immediate = 0x03001f11,
1339	.key = 0x81000000,
1340	.data = vendor_textual_descriptor,
1341};
1342
1343static struct fw_descriptor model_id_descriptor = {
1344	.length = ARRAY_SIZE(model_textual_descriptor),
1345	.immediate = 0x17023901,
1346	.key = 0x81000000,
1347	.data = model_textual_descriptor,
1348};
1349
1350static int __init fw_core_init(void)
1351{
1352	int ret;
1353
1354	fw_workqueue = alloc_workqueue("firewire", WQ_MEM_RECLAIM, 0);
1355	if (!fw_workqueue)
1356		return -ENOMEM;
1357
1358	ret = bus_register(&fw_bus_type);
1359	if (ret < 0) {
1360		destroy_workqueue(fw_workqueue);
1361		return ret;
1362	}
1363
1364	fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1365	if (fw_cdev_major < 0) {
1366		bus_unregister(&fw_bus_type);
1367		destroy_workqueue(fw_workqueue);
1368		return fw_cdev_major;
1369	}
1370
1371	fw_core_add_address_handler(&topology_map, &topology_map_region);
1372	fw_core_add_address_handler(&registers, &registers_region);
1373	fw_core_add_address_handler(&low_memory, &low_memory_region);
1374	fw_core_add_descriptor(&vendor_id_descriptor);
1375	fw_core_add_descriptor(&model_id_descriptor);
1376
1377	return 0;
1378}
1379
1380static void __exit fw_core_cleanup(void)
1381{
1382	unregister_chrdev(fw_cdev_major, "firewire");
1383	bus_unregister(&fw_bus_type);
1384	destroy_workqueue(fw_workqueue);
1385	idr_destroy(&fw_device_idr);
1386}
1387
1388module_init(fw_core_init);
1389module_exit(fw_core_cleanup);