1/*
   2 * Core IEEE1394 transaction logic
   3 *
   4 * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software Foundation,
  18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19 */
  20
  21#include <linux/bug.h>
  22#include <linux/completion.h>
  23#include <linux/device.h>
  24#include <linux/errno.h>
  25#include <linux/firewire.h>
  26#include <linux/firewire-constants.h>
  27#include <linux/fs.h>
  28#include <linux/init.h>
  29#include <linux/idr.h>
  30#include <linux/jiffies.h>
  31#include <linux/kernel.h>
  32#include <linux/list.h>
  33#include <linux/module.h>
  34#include <linux/slab.h>
  35#include <linux/spinlock.h>
  36#include <linux/string.h>
  37#include <linux/timer.h>
  38#include <linux/types.h>
  39#include <linux/workqueue.h>
  40
  41#include <asm/byteorder.h>
  42
  43#include "core.h"
  44
  45#define HEADER_PRI(pri)			((pri) << 0)
  46#define HEADER_TCODE(tcode)		((tcode) << 4)
  47#define HEADER_RETRY(retry)		((retry) << 8)
  48#define HEADER_TLABEL(tlabel)		((tlabel) << 10)
  49#define HEADER_DESTINATION(destination)	((destination) << 16)
  50#define HEADER_SOURCE(source)		((source) << 16)
  51#define HEADER_RCODE(rcode)		((rcode) << 12)
  52#define HEADER_OFFSET_HIGH(offset_high)	((offset_high) << 0)
  53#define HEADER_DATA_LENGTH(length)	((length) << 16)
  54#define HEADER_EXTENDED_TCODE(tcode)	((tcode) << 0)
  55
  56#define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
  57#define HEADER_GET_TLABEL(q)		(((q) >> 10) & 0x3f)
  58#define HEADER_GET_RCODE(q)		(((q) >> 12) & 0x0f)
  59#define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
  60#define HEADER_GET_SOURCE(q)		(((q) >> 16) & 0xffff)
  61#define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
  62#define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
  63#define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
  64
  65#define HEADER_DESTINATION_IS_BROADCAST(q) \
  66	(((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
  67
  68#define PHY_PACKET_CONFIG	0x0
  69#define PHY_PACKET_LINK_ON	0x1
  70#define PHY_PACKET_SELF_ID	0x2
  71
  72#define PHY_CONFIG_GAP_COUNT(gap_count)	(((gap_count) << 16) | (1 << 22))
  73#define PHY_CONFIG_ROOT_ID(node_id)	((((node_id) & 0x3f) << 24) | (1 << 23))
  74#define PHY_IDENTIFIER(id)		((id) << 30)
  75
  76/* returns 0 if the split timeout handler is already running */
  77static int try_cancel_split_timeout(struct fw_transaction *t)
  78{
  79	if (t->is_split_transaction)
  80		return del_timer(&t->split_timeout_timer);
  81	else
  82		return 1;
  83}
  84
  85static int close_transaction(struct fw_transaction *transaction,
  86			     struct fw_card *card, int rcode)
  87{
  88	struct fw_transaction *t;
  89	unsigned long flags;
  90
  91	spin_lock_irqsave(&card->lock, flags);
  92	list_for_each_entry(t, &card->transaction_list, link) {
  93		if (t == transaction) {
  94			if (!try_cancel_split_timeout(t)) {
  95				spin_unlock_irqrestore(&card->lock, flags);
  96				goto timed_out;
  97			}
  98			list_del_init(&t->link);
  99			card->tlabel_mask &= ~(1ULL << t->tlabel);
 100			break;
 101		}
 102	}
 103	spin_unlock_irqrestore(&card->lock, flags);
 104
 105	if (&t->link != &card->transaction_list) {
 106		t->callback(card, rcode, NULL, 0, t->callback_data);
 107		return 0;
 108	}
 109
 110 timed_out:
 111	return -ENOENT;
 112}
 113
 114/*
 115 * Only valid for transactions that are potentially pending (ie have
 116 * been sent).
 117 */
 118int fw_cancel_transaction(struct fw_card *card,
 119			  struct fw_transaction *transaction)
 120{
 121	/*
 122	 * Cancel the packet transmission if it's still queued.  That
 123	 * will call the packet transmission callback which cancels
 124	 * the transaction.
 125	 */
 126
 127	if (card->driver->cancel_packet(card, &transaction->packet) == 0)
 128		return 0;
 129
 130	/*
 131	 * If the request packet has already been sent, we need to see
 132	 * if the transaction is still pending and remove it in that case.
 133	 */
 134
 135	return close_transaction(transaction, card, RCODE_CANCELLED);
 136}
 137EXPORT_SYMBOL(fw_cancel_transaction);
 138
 139static void split_transaction_timeout_callback(unsigned long data)
 140{
 141	struct fw_transaction *t = (struct fw_transaction *)data;
 142	struct fw_card *card = t->card;
 143	unsigned long flags;
 144
 145	spin_lock_irqsave(&card->lock, flags);
 146	if (list_empty(&t->link)) {
 147		spin_unlock_irqrestore(&card->lock, flags);
 148		return;
 149	}
 150	list_del(&t->link);
 151	card->tlabel_mask &= ~(1ULL << t->tlabel);
 152	spin_unlock_irqrestore(&card->lock, flags);
 153
 154	t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 155}
 156
 157static void start_split_transaction_timeout(struct fw_transaction *t,
 158					    struct fw_card *card)
 159{
 160	unsigned long flags;
 161
 162	spin_lock_irqsave(&card->lock, flags);
 163
 164	if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
 165		spin_unlock_irqrestore(&card->lock, flags);
 166		return;
 167	}
 168
 169	t->is_split_transaction = true;
 170	mod_timer(&t->split_timeout_timer,
 171		  jiffies + card->split_timeout_jiffies);
 172
 173	spin_unlock_irqrestore(&card->lock, flags);
 174}
 175
 176static void transmit_complete_callback(struct fw_packet *packet,
 177				       struct fw_card *card, int status)
 178{
 179	struct fw_transaction *t =
 180	    container_of(packet, struct fw_transaction, packet);
 181
 182	switch (status) {
 183	case ACK_COMPLETE:
 184		close_transaction(t, card, RCODE_COMPLETE);
 185		break;
 186	case ACK_PENDING:
 187		start_split_transaction_timeout(t, card);
 188		break;
 189	case ACK_BUSY_X:
 190	case ACK_BUSY_A:
 191	case ACK_BUSY_B:
 192		close_transaction(t, card, RCODE_BUSY);
 193		break;
 194	case ACK_DATA_ERROR:
 195		close_transaction(t, card, RCODE_DATA_ERROR);
 196		break;
 197	case ACK_TYPE_ERROR:
 198		close_transaction(t, card, RCODE_TYPE_ERROR);
 199		break;
 200	default:
 201		/*
 202		 * In this case the ack is really a juju specific
 203		 * rcode, so just forward that to the callback.
 204		 */
 205		close_transaction(t, card, status);
 206		break;
 207	}
 208}
 209
 210static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 211		int destination_id, int source_id, int generation, int speed,
 212		unsigned long long offset, void *payload, size_t length)
 213{
 214	int ext_tcode;
 215
 216	if (tcode == TCODE_STREAM_DATA) {
 217		packet->header[0] =
 218			HEADER_DATA_LENGTH(length) |
 219			destination_id |
 220			HEADER_TCODE(TCODE_STREAM_DATA);
 221		packet->header_length = 4;
 222		packet->payload = payload;
 223		packet->payload_length = length;
 224
 225		goto common;
 226	}
 227
 228	if (tcode > 0x10) {
 229		ext_tcode = tcode & ~0x10;
 230		tcode = TCODE_LOCK_REQUEST;
 231	} else
 232		ext_tcode = 0;
 233
 234	packet->header[0] =
 235		HEADER_RETRY(RETRY_X) |
 236		HEADER_TLABEL(tlabel) |
 237		HEADER_TCODE(tcode) |
 238		HEADER_DESTINATION(destination_id);
 239	packet->header[1] =
 240		HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
 241	packet->header[2] =
 242		offset;
 243
 244	switch (tcode) {
 245	case TCODE_WRITE_QUADLET_REQUEST:
 246		packet->header[3] = *(u32 *)payload;
 247		packet->header_length = 16;
 248		packet->payload_length = 0;
 249		break;
 250
 251	case TCODE_LOCK_REQUEST:
 252	case TCODE_WRITE_BLOCK_REQUEST:
 253		packet->header[3] =
 254			HEADER_DATA_LENGTH(length) |
 255			HEADER_EXTENDED_TCODE(ext_tcode);
 256		packet->header_length = 16;
 257		packet->payload = payload;
 258		packet->payload_length = length;
 259		break;
 260
 261	case TCODE_READ_QUADLET_REQUEST:
 262		packet->header_length = 12;
 263		packet->payload_length = 0;
 264		break;
 265
 266	case TCODE_READ_BLOCK_REQUEST:
 267		packet->header[3] =
 268			HEADER_DATA_LENGTH(length) |
 269			HEADER_EXTENDED_TCODE(ext_tcode);
 270		packet->header_length = 16;
 271		packet->payload_length = 0;
 272		break;
 273
 274	default:
 275		WARN(1, "wrong tcode %d\n", tcode);
 276	}
 277 common:
 278	packet->speed = speed;
 279	packet->generation = generation;
 280	packet->ack = 0;
 281	packet->payload_mapped = false;
 282}
 283
 284static int allocate_tlabel(struct fw_card *card)
 285{
 286	int tlabel;
 287
 288	tlabel = card->current_tlabel;
 289	while (card->tlabel_mask & (1ULL << tlabel)) {
 290		tlabel = (tlabel + 1) & 0x3f;
 291		if (tlabel == card->current_tlabel)
 292			return -EBUSY;
 293	}
 294
 295	card->current_tlabel = (tlabel + 1) & 0x3f;
 296	card->tlabel_mask |= 1ULL << tlabel;
 297
 298	return tlabel;
 299}
 300
 301/**
 302 * fw_send_request() - submit a request packet for transmission
 303 * @card:		interface to send the request at
 304 * @t:			transaction instance to which the request belongs
 305 * @tcode:		transaction code
 306 * @destination_id:	destination node ID, consisting of bus_ID and phy_ID
 307 * @generation:		bus generation in which request and response are valid
 308 * @speed:		transmission speed
 309 * @offset:		48bit wide offset into destination's address space
 310 * @payload:		data payload for the request subaction
 311 * @length:		length of the payload, in bytes
 312 * @callback:		function to be called when the transaction is completed
 313 * @callback_data:	data to be passed to the transaction completion callback
 314 *
 315 * Submit a request packet into the asynchronous request transmission queue.
 316 * Can be called from atomic context.  If you prefer a blocking API, use
 317 * fw_run_transaction() in a context that can sleep.
 318 *
 319 * In case of lock requests, specify one of the firewire-core specific %TCODE_
 320 * constants instead of %TCODE_LOCK_REQUEST in @tcode.
 321 *
 322 * Make sure that the value in @destination_id is not older than the one in
 323 * @generation.  Otherwise the request is in danger to be sent to a wrong node.
 324 *
 325 * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
 326 * needs to synthesize @destination_id with fw_stream_packet_destination_id().
 327 * It will contain tag, channel, and sy data instead of a node ID then.
 328 *
 329 * The payload buffer at @data is going to be DMA-mapped except in case of
 330 * @length <= 8 or of local (loopback) requests.  Hence make sure that the
 331 * buffer complies with the restrictions of the streaming DMA mapping API.
 332 * @payload must not be freed before the @callback is called.
 333 *
 334 * In case of request types without payload, @data is NULL and @length is 0.
 335 *
 336 * After the transaction is completed successfully or unsuccessfully, the
 337 * @callback will be called.  Among its parameters is the response code which
 338 * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
 339 * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
 340 * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
 341 * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
 342 * generation, or missing ACK respectively.
 343 *
 344 * Note some timing corner cases:  fw_send_request() may complete much earlier
 345 * than when the request packet actually hits the wire.  On the other hand,
 346 * transaction completion and hence execution of @callback may happen even
 347 * before fw_send_request() returns.
 348 */
 349void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 350		     int destination_id, int generation, int speed,
 351		     unsigned long long offset, void *payload, size_t length,
 352		     fw_transaction_callback_t callback, void *callback_data)
 353{
 354	unsigned long flags;
 355	int tlabel;
 356
 357	/*
 358	 * Allocate tlabel from the bitmap and put the transaction on
 359	 * the list while holding the card spinlock.
 360	 */
 361
 362	spin_lock_irqsave(&card->lock, flags);
 363
 364	tlabel = allocate_tlabel(card);
 365	if (tlabel < 0) {
 366		spin_unlock_irqrestore(&card->lock, flags);
 367		callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 368		return;
 369	}
 370
 371	t->node_id = destination_id;
 372	t->tlabel = tlabel;
 373	t->card = card;
 374	t->is_split_transaction = false;
 375	setup_timer(&t->split_timeout_timer,
 376		    split_transaction_timeout_callback, (unsigned long)t);
 377	t->callback = callback;
 378	t->callback_data = callback_data;
 379
 380	fw_fill_request(&t->packet, tcode, t->tlabel,
 381			destination_id, card->node_id, generation,
 382			speed, offset, payload, length);
 383	t->packet.callback = transmit_complete_callback;
 384
 385	list_add_tail(&t->link, &card->transaction_list);
 386
 387	spin_unlock_irqrestore(&card->lock, flags);
 388
 389	card->driver->send_request(card, &t->packet);
 390}
 391EXPORT_SYMBOL(fw_send_request);
 392
 393struct transaction_callback_data {
 394	struct completion done;
 395	void *payload;
 396	int rcode;
 397};
 398
 399static void transaction_callback(struct fw_card *card, int rcode,
 400				 void *payload, size_t length, void *data)
 401{
 402	struct transaction_callback_data *d = data;
 403
 404	if (rcode == RCODE_COMPLETE)
 405		memcpy(d->payload, payload, length);
 406	d->rcode = rcode;
 407	complete(&d->done);
 408}
 409
 410/**
 411 * fw_run_transaction() - send request and sleep until transaction is completed
 412 *
 413 * Returns the RCODE.  See fw_send_request() for parameter documentation.
 414 * Unlike fw_send_request(), @data points to the payload of the request or/and
 415 * to the payload of the response.  DMA mapping restrictions apply to outbound
 416 * request payloads of >= 8 bytes but not to inbound response payloads.
 417 */
 418int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 419		       int generation, int speed, unsigned long long offset,
 420		       void *payload, size_t length)
 421{
 422	struct transaction_callback_data d;
 423	struct fw_transaction t;
 424
 425	init_timer_on_stack(&t.split_timeout_timer);
 426	init_completion(&d.done);
 427	d.payload = payload;
 428	fw_send_request(card, &t, tcode, destination_id, generation, speed,
 429			offset, payload, length, transaction_callback, &d);
 430	wait_for_completion(&d.done);
 431	destroy_timer_on_stack(&t.split_timeout_timer);
 432
 433	return d.rcode;
 434}
 435EXPORT_SYMBOL(fw_run_transaction);
 436
 437static DEFINE_MUTEX(phy_config_mutex);
 438static DECLARE_COMPLETION(phy_config_done);
 439
 440static void transmit_phy_packet_callback(struct fw_packet *packet,
 441					 struct fw_card *card, int status)
 442{
 443	complete(&phy_config_done);
 444}
 445
 446static struct fw_packet phy_config_packet = {
 447	.header_length	= 12,
 448	.header[0]	= TCODE_LINK_INTERNAL << 4,
 449	.payload_length	= 0,
 450	.speed		= SCODE_100,
 451	.callback	= transmit_phy_packet_callback,
 452};
 453
 454void fw_send_phy_config(struct fw_card *card,
 455			int node_id, int generation, int gap_count)
 456{
 457	long timeout = DIV_ROUND_UP(HZ, 10);
 458	u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
 459
 460	if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
 461		data |= PHY_CONFIG_ROOT_ID(node_id);
 462
 463	if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
 464		gap_count = card->driver->read_phy_reg(card, 1);
 465		if (gap_count < 0)
 466			return;
 467
 468		gap_count &= 63;
 469		if (gap_count == 63)
 470			return;
 471	}
 472	data |= PHY_CONFIG_GAP_COUNT(gap_count);
 473
 474	mutex_lock(&phy_config_mutex);
 475
 476	phy_config_packet.header[1] = data;
 477	phy_config_packet.header[2] = ~data;
 478	phy_config_packet.generation = generation;
 479	INIT_COMPLETION(phy_config_done);
 480
 481	card->driver->send_request(card, &phy_config_packet);
 482	wait_for_completion_timeout(&phy_config_done, timeout);
 483
 484	mutex_unlock(&phy_config_mutex);
 485}
 486
 487static struct fw_address_handler *lookup_overlapping_address_handler(
 488	struct list_head *list, unsigned long long offset, size_t length)
 489{
 490	struct fw_address_handler *handler;
 491
 492	list_for_each_entry(handler, list, link) {
 493		if (handler->offset < offset + length &&
 494		    offset < handler->offset + handler->length)
 495			return handler;
 496	}
 497
 498	return NULL;
 499}
 500
 501static bool is_enclosing_handler(struct fw_address_handler *handler,
 502				 unsigned long long offset, size_t length)
 503{
 504	return handler->offset <= offset &&
 505		offset + length <= handler->offset + handler->length;
 506}
 507
 508static struct fw_address_handler *lookup_enclosing_address_handler(
 509	struct list_head *list, unsigned long long offset, size_t length)
 510{
 511	struct fw_address_handler *handler;
 512
 513	list_for_each_entry(handler, list, link) {
 514		if (is_enclosing_handler(handler, offset, length))
 515			return handler;
 516	}
 517
 518	return NULL;
 519}
 520
 521static DEFINE_SPINLOCK(address_handler_lock);
 522static LIST_HEAD(address_handler_list);
 523
 524const struct fw_address_region fw_high_memory_region =
 525	{ .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };
 526EXPORT_SYMBOL(fw_high_memory_region);
 527
 528#if 0
 529const struct fw_address_region fw_low_memory_region =
 530	{ .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };
 531const struct fw_address_region fw_private_region =
 532	{ .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 533const struct fw_address_region fw_csr_region =
 534	{ .start = CSR_REGISTER_BASE,
 535	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 536const struct fw_address_region fw_unit_space_region =
 537	{ .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 538#endif  /*  0  */
 539
 540static bool is_in_fcp_region(u64 offset, size_t length)
 541{
 542	return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 543		offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
 544}
 545
 546/**
 547 * fw_core_add_address_handler() - register for incoming requests
 548 * @handler:	callback
 549 * @region:	region in the IEEE 1212 node space address range
 550 *
 551 * region->start, ->end, and handler->length have to be quadlet-aligned.
 552 *
 553 * When a request is received that falls within the specified address range,
 554 * the specified callback is invoked.  The parameters passed to the callback
 555 * give the details of the particular request.
 556 *
 557 * Return value:  0 on success, non-zero otherwise.
 558 *
 559 * The start offset of the handler's address region is determined by
 560 * fw_core_add_address_handler() and is returned in handler->offset.
 561 *
 562 * Address allocations are exclusive, except for the FCP registers.
 563 */
 564int fw_core_add_address_handler(struct fw_address_handler *handler,
 565				const struct fw_address_region *region)
 566{
 567	struct fw_address_handler *other;
 
 568	int ret = -EBUSY;
 569
 570	if (region->start & 0xffff000000000003ULL ||
 571	    region->start >= region->end ||
 572	    region->end   > 0x0001000000000000ULL ||
 573	    handler->length & 3 ||
 574	    handler->length == 0)
 575		return -EINVAL;
 576
 577	spin_lock_bh(&address_handler_lock);
 578
 579	handler->offset = region->start;
 580	while (handler->offset + handler->length <= region->end) {
 581		if (is_in_fcp_region(handler->offset, handler->length))
 582			other = NULL;
 583		else
 584			other = lookup_overlapping_address_handler
 585					(&address_handler_list,
 586					 handler->offset, handler->length);
 587		if (other != NULL) {
 588			handler->offset += other->length;
 589		} else {
 590			list_add_tail(&handler->link, &address_handler_list);
 591			ret = 0;
 592			break;
 593		}
 594	}
 595
 596	spin_unlock_bh(&address_handler_lock);
 597
 598	return ret;
 599}
 600EXPORT_SYMBOL(fw_core_add_address_handler);
 601
 602/**
 603 * fw_core_remove_address_handler() - unregister an address handler
 604 *
 605 * When fw_core_remove_address_handler() returns, @handler->callback() is
 606 * guaranteed to not run on any CPU anymore.
 607 */
 608void fw_core_remove_address_handler(struct fw_address_handler *handler)
 609{
 610	spin_lock_bh(&address_handler_lock);
 
 
 611	list_del(&handler->link);
 612	spin_unlock_bh(&address_handler_lock);
 613}
 614EXPORT_SYMBOL(fw_core_remove_address_handler);
 615
 616struct fw_request {
 617	struct fw_packet response;
 618	u32 request_header[4];
 619	int ack;
 620	u32 length;
 621	u32 data[0];
 622};
 623
 624static void free_response_callback(struct fw_packet *packet,
 625				   struct fw_card *card, int status)
 626{
 627	struct fw_request *request;
 628
 629	request = container_of(packet, struct fw_request, response);
 630	kfree(request);
 631}
 632
 633int fw_get_response_length(struct fw_request *r)
 634{
 635	int tcode, ext_tcode, data_length;
 636
 637	tcode = HEADER_GET_TCODE(r->request_header[0]);
 638
 639	switch (tcode) {
 640	case TCODE_WRITE_QUADLET_REQUEST:
 641	case TCODE_WRITE_BLOCK_REQUEST:
 642		return 0;
 643
 644	case TCODE_READ_QUADLET_REQUEST:
 645		return 4;
 646
 647	case TCODE_READ_BLOCK_REQUEST:
 648		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 649		return data_length;
 650
 651	case TCODE_LOCK_REQUEST:
 652		ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 653		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 654		switch (ext_tcode) {
 655		case EXTCODE_FETCH_ADD:
 656		case EXTCODE_LITTLE_ADD:
 657			return data_length;
 658		default:
 659			return data_length / 2;
 660		}
 661
 662	default:
 663		WARN(1, "wrong tcode %d\n", tcode);
 664		return 0;
 665	}
 666}
 667
 668void fw_fill_response(struct fw_packet *response, u32 *request_header,
 669		      int rcode, void *payload, size_t length)
 670{
 671	int tcode, tlabel, extended_tcode, source, destination;
 672
 673	tcode          = HEADER_GET_TCODE(request_header[0]);
 674	tlabel         = HEADER_GET_TLABEL(request_header[0]);
 675	source         = HEADER_GET_DESTINATION(request_header[0]);
 676	destination    = HEADER_GET_SOURCE(request_header[1]);
 677	extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 678
 679	response->header[0] =
 680		HEADER_RETRY(RETRY_1) |
 681		HEADER_TLABEL(tlabel) |
 682		HEADER_DESTINATION(destination);
 683	response->header[1] =
 684		HEADER_SOURCE(source) |
 685		HEADER_RCODE(rcode);
 686	response->header[2] = 0;
 687
 688	switch (tcode) {
 689	case TCODE_WRITE_QUADLET_REQUEST:
 690	case TCODE_WRITE_BLOCK_REQUEST:
 691		response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 692		response->header_length = 12;
 693		response->payload_length = 0;
 694		break;
 695
 696	case TCODE_READ_QUADLET_REQUEST:
 697		response->header[0] |=
 698			HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 699		if (payload != NULL)
 700			response->header[3] = *(u32 *)payload;
 701		else
 702			response->header[3] = 0;
 703		response->header_length = 16;
 704		response->payload_length = 0;
 705		break;
 706
 707	case TCODE_READ_BLOCK_REQUEST:
 708	case TCODE_LOCK_REQUEST:
 709		response->header[0] |= HEADER_TCODE(tcode + 2);
 710		response->header[3] =
 711			HEADER_DATA_LENGTH(length) |
 712			HEADER_EXTENDED_TCODE(extended_tcode);
 713		response->header_length = 16;
 714		response->payload = payload;
 715		response->payload_length = length;
 716		break;
 717
 718	default:
 719		WARN(1, "wrong tcode %d\n", tcode);
 720	}
 721
 722	response->payload_mapped = false;
 723}
 724EXPORT_SYMBOL(fw_fill_response);
 725
 726static u32 compute_split_timeout_timestamp(struct fw_card *card,
 727					   u32 request_timestamp)
 728{
 729	unsigned int cycles;
 730	u32 timestamp;
 731
 732	cycles = card->split_timeout_cycles;
 733	cycles += request_timestamp & 0x1fff;
 734
 735	timestamp = request_timestamp & ~0x1fff;
 736	timestamp += (cycles / 8000) << 13;
 737	timestamp |= cycles % 8000;
 738
 739	return timestamp;
 740}
 741
 742static struct fw_request *allocate_request(struct fw_card *card,
 743					   struct fw_packet *p)
 744{
 745	struct fw_request *request;
 746	u32 *data, length;
 747	int request_tcode;
 748
 749	request_tcode = HEADER_GET_TCODE(p->header[0]);
 750	switch (request_tcode) {
 751	case TCODE_WRITE_QUADLET_REQUEST:
 752		data = &p->header[3];
 753		length = 4;
 754		break;
 755
 756	case TCODE_WRITE_BLOCK_REQUEST:
 757	case TCODE_LOCK_REQUEST:
 758		data = p->payload;
 759		length = HEADER_GET_DATA_LENGTH(p->header[3]);
 760		break;
 761
 762	case TCODE_READ_QUADLET_REQUEST:
 763		data = NULL;
 764		length = 4;
 765		break;
 766
 767	case TCODE_READ_BLOCK_REQUEST:
 768		data = NULL;
 769		length = HEADER_GET_DATA_LENGTH(p->header[3]);
 770		break;
 771
 772	default:
 773		fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
 774			 p->header[0], p->header[1], p->header[2]);
 775		return NULL;
 776	}
 777
 778	request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 779	if (request == NULL)
 780		return NULL;
 781
 782	request->response.speed = p->speed;
 783	request->response.timestamp =
 784			compute_split_timeout_timestamp(card, p->timestamp);
 785	request->response.generation = p->generation;
 786	request->response.ack = 0;
 787	request->response.callback = free_response_callback;
 788	request->ack = p->ack;
 789	request->length = length;
 790	if (data)
 791		memcpy(request->data, data, length);
 792
 793	memcpy(request->request_header, p->header, sizeof(p->header));
 794
 795	return request;
 796}
 797
 798void fw_send_response(struct fw_card *card,
 799		      struct fw_request *request, int rcode)
 800{
 801	if (WARN_ONCE(!request, "invalid for FCP address handlers"))
 802		return;
 803
 804	/* unified transaction or broadcast transaction: don't respond */
 805	if (request->ack != ACK_PENDING ||
 806	    HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 807		kfree(request);
 808		return;
 809	}
 810
 811	if (rcode == RCODE_COMPLETE)
 812		fw_fill_response(&request->response, request->request_header,
 813				 rcode, request->data,
 814				 fw_get_response_length(request));
 815	else
 816		fw_fill_response(&request->response, request->request_header,
 817				 rcode, NULL, 0);
 818
 819	card->driver->send_response(card, &request->response);
 820}
 821EXPORT_SYMBOL(fw_send_response);
 822
 823/**
 824 * fw_get_request_speed() - returns speed at which the @request was received
 825 */
 826int fw_get_request_speed(struct fw_request *request)
 827{
 828	return request->response.speed;
 829}
 830EXPORT_SYMBOL(fw_get_request_speed);
 831
 832static void handle_exclusive_region_request(struct fw_card *card,
 833					    struct fw_packet *p,
 834					    struct fw_request *request,
 835					    unsigned long long offset)
 836{
 837	struct fw_address_handler *handler;
 
 838	int tcode, destination, source;
 839
 840	destination = HEADER_GET_DESTINATION(p->header[0]);
 841	source      = HEADER_GET_SOURCE(p->header[1]);
 842	tcode       = HEADER_GET_TCODE(p->header[0]);
 843	if (tcode == TCODE_LOCK_REQUEST)
 844		tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 845
 846	spin_lock_bh(&address_handler_lock);
 847	handler = lookup_enclosing_address_handler(&address_handler_list,
 848						   offset, request->length);
 849	if (handler)
 
 
 
 
 
 
 
 
 
 
 
 
 850		handler->address_callback(card, request,
 851					  tcode, destination, source,
 852					  p->generation, offset,
 853					  request->data, request->length,
 854					  handler->callback_data);
 855	spin_unlock_bh(&address_handler_lock);
 856
 857	if (!handler)
 858		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 859}
 860
 861static void handle_fcp_region_request(struct fw_card *card,
 862				      struct fw_packet *p,
 863				      struct fw_request *request,
 864				      unsigned long long offset)
 865{
 866	struct fw_address_handler *handler;
 
 867	int tcode, destination, source;
 868
 869	if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 870	     offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
 871	    request->length > 0x200) {
 872		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 873
 874		return;
 875	}
 876
 877	tcode       = HEADER_GET_TCODE(p->header[0]);
 878	destination = HEADER_GET_DESTINATION(p->header[0]);
 879	source      = HEADER_GET_SOURCE(p->header[1]);
 880
 881	if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
 882	    tcode != TCODE_WRITE_BLOCK_REQUEST) {
 883		fw_send_response(card, request, RCODE_TYPE_ERROR);
 884
 885		return;
 886	}
 887
 888	spin_lock_bh(&address_handler_lock);
 889	list_for_each_entry(handler, &address_handler_list, link) {
 890		if (is_enclosing_handler(handler, offset, request->length))
 891			handler->address_callback(card, NULL, tcode,
 892						  destination, source,
 893						  p->generation, offset,
 894						  request->data,
 895						  request->length,
 896						  handler->callback_data);
 897	}
 898	spin_unlock_bh(&address_handler_lock);
 899
 900	fw_send_response(card, request, RCODE_COMPLETE);
 901}
 902
 903void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 904{
 905	struct fw_request *request;
 906	unsigned long long offset;
 907
 908	if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 909		return;
 910
 911	if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
 912		fw_cdev_handle_phy_packet(card, p);
 913		return;
 914	}
 915
 916	request = allocate_request(card, p);
 917	if (request == NULL) {
 918		/* FIXME: send statically allocated busy packet. */
 919		return;
 920	}
 921
 922	offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
 923		p->header[2];
 924
 925	if (!is_in_fcp_region(offset, request->length))
 926		handle_exclusive_region_request(card, p, request, offset);
 927	else
 928		handle_fcp_region_request(card, p, request, offset);
 929
 930}
 931EXPORT_SYMBOL(fw_core_handle_request);
 932
 933void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
 934{
 935	struct fw_transaction *t;
 936	unsigned long flags;
 937	u32 *data;
 938	size_t data_length;
 939	int tcode, tlabel, source, rcode;
 940
 941	tcode	= HEADER_GET_TCODE(p->header[0]);
 942	tlabel	= HEADER_GET_TLABEL(p->header[0]);
 943	source	= HEADER_GET_SOURCE(p->header[1]);
 944	rcode	= HEADER_GET_RCODE(p->header[1]);
 945
 946	spin_lock_irqsave(&card->lock, flags);
 947	list_for_each_entry(t, &card->transaction_list, link) {
 948		if (t->node_id == source && t->tlabel == tlabel) {
 949			if (!try_cancel_split_timeout(t)) {
 950				spin_unlock_irqrestore(&card->lock, flags);
 951				goto timed_out;
 952			}
 953			list_del_init(&t->link);
 954			card->tlabel_mask &= ~(1ULL << t->tlabel);
 955			break;
 956		}
 957	}
 958	spin_unlock_irqrestore(&card->lock, flags);
 959
 960	if (&t->link == &card->transaction_list) {
 961 timed_out:
 962		fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
 963			  source, tlabel);
 964		return;
 965	}
 966
 967	/*
 968	 * FIXME: sanity check packet, is length correct, does tcodes
 969	 * and addresses match.
 970	 */
 971
 972	switch (tcode) {
 973	case TCODE_READ_QUADLET_RESPONSE:
 974		data = (u32 *) &p->header[3];
 975		data_length = 4;
 976		break;
 977
 978	case TCODE_WRITE_RESPONSE:
 979		data = NULL;
 980		data_length = 0;
 981		break;
 982
 983	case TCODE_READ_BLOCK_RESPONSE:
 984	case TCODE_LOCK_RESPONSE:
 985		data = p->payload;
 986		data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
 987		break;
 988
 989	default:
 990		/* Should never happen, this is just to shut up gcc. */
 991		data = NULL;
 992		data_length = 0;
 993		break;
 994	}
 995
 996	/*
 997	 * The response handler may be executed while the request handler
 998	 * is still pending.  Cancel the request handler.
 999	 */
1000	card->driver->cancel_packet(card, &t->packet);
1001
1002	t->callback(card, rcode, data, data_length, t->callback_data);
1003}
1004EXPORT_SYMBOL(fw_core_handle_response);
1005
1006/**
1007 * fw_rcode_string - convert a firewire result code to an error description
1008 * @rcode: the result code
1009 */
1010const char *fw_rcode_string(int rcode)
1011{
1012	static const char *const names[] = {
1013		[RCODE_COMPLETE]       = "no error",
1014		[RCODE_CONFLICT_ERROR] = "conflict error",
1015		[RCODE_DATA_ERROR]     = "data error",
1016		[RCODE_TYPE_ERROR]     = "type error",
1017		[RCODE_ADDRESS_ERROR]  = "address error",
1018		[RCODE_SEND_ERROR]     = "send error",
1019		[RCODE_CANCELLED]      = "timeout",
1020		[RCODE_BUSY]           = "busy",
1021		[RCODE_GENERATION]     = "bus reset",
1022		[RCODE_NO_ACK]         = "no ack",
1023	};
1024
1025	if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1026		return names[rcode];
1027	else
1028		return "unknown";
1029}
1030EXPORT_SYMBOL(fw_rcode_string);
1031
1032static const struct fw_address_region topology_map_region =
1033	{ .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1034	  .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1035
1036static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1037		int tcode, int destination, int source, int generation,
1038		unsigned long long offset, void *payload, size_t length,
1039		void *callback_data)
1040{
1041	int start;
1042
1043	if (!TCODE_IS_READ_REQUEST(tcode)) {
1044		fw_send_response(card, request, RCODE_TYPE_ERROR);
1045		return;
1046	}
1047
1048	if ((offset & 3) > 0 || (length & 3) > 0) {
1049		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1050		return;
1051	}
1052
1053	start = (offset - topology_map_region.start) / 4;
1054	memcpy(payload, &card->topology_map[start], length);
1055
1056	fw_send_response(card, request, RCODE_COMPLETE);
1057}
1058
1059static struct fw_address_handler topology_map = {
1060	.length			= 0x400,
1061	.address_callback	= handle_topology_map,
1062};
1063
1064static const struct fw_address_region registers_region =
1065	{ .start = CSR_REGISTER_BASE,
1066	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1067
1068static void update_split_timeout(struct fw_card *card)
1069{
1070	unsigned int cycles;
1071
1072	cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1073
1074	/* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1075	cycles = clamp(cycles, 800u, 3u * 8000u);
1076
1077	card->split_timeout_cycles = cycles;
1078	card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1079}
1080
1081static void handle_registers(struct fw_card *card, struct fw_request *request,
1082		int tcode, int destination, int source, int generation,
1083		unsigned long long offset, void *payload, size_t length,
1084		void *callback_data)
1085{
1086	int reg = offset & ~CSR_REGISTER_BASE;
1087	__be32 *data = payload;
1088	int rcode = RCODE_COMPLETE;
1089	unsigned long flags;
1090
1091	switch (reg) {
1092	case CSR_PRIORITY_BUDGET:
1093		if (!card->priority_budget_implemented) {
1094			rcode = RCODE_ADDRESS_ERROR;
1095			break;
1096		}
1097		/* else fall through */
1098
1099	case CSR_NODE_IDS:
1100		/*
1101		 * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1102		 * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1103		 */
1104		/* fall through */
1105
1106	case CSR_STATE_CLEAR:
1107	case CSR_STATE_SET:
1108	case CSR_CYCLE_TIME:
1109	case CSR_BUS_TIME:
1110	case CSR_BUSY_TIMEOUT:
1111		if (tcode == TCODE_READ_QUADLET_REQUEST)
1112			*data = cpu_to_be32(card->driver->read_csr(card, reg));
1113		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1114			card->driver->write_csr(card, reg, be32_to_cpu(*data));
1115		else
1116			rcode = RCODE_TYPE_ERROR;
1117		break;
1118
1119	case CSR_RESET_START:
1120		if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1121			card->driver->write_csr(card, CSR_STATE_CLEAR,
1122						CSR_STATE_BIT_ABDICATE);
1123		else
1124			rcode = RCODE_TYPE_ERROR;
1125		break;
1126
1127	case CSR_SPLIT_TIMEOUT_HI:
1128		if (tcode == TCODE_READ_QUADLET_REQUEST) {
1129			*data = cpu_to_be32(card->split_timeout_hi);
1130		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1131			spin_lock_irqsave(&card->lock, flags);
1132			card->split_timeout_hi = be32_to_cpu(*data) & 7;
1133			update_split_timeout(card);
1134			spin_unlock_irqrestore(&card->lock, flags);
1135		} else {
1136			rcode = RCODE_TYPE_ERROR;
1137		}
1138		break;
1139
1140	case CSR_SPLIT_TIMEOUT_LO:
1141		if (tcode == TCODE_READ_QUADLET_REQUEST) {
1142			*data = cpu_to_be32(card->split_timeout_lo);
1143		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1144			spin_lock_irqsave(&card->lock, flags);
1145			card->split_timeout_lo =
1146					be32_to_cpu(*data) & 0xfff80000;
1147			update_split_timeout(card);
1148			spin_unlock_irqrestore(&card->lock, flags);
1149		} else {
1150			rcode = RCODE_TYPE_ERROR;
1151		}
1152		break;
1153
1154	case CSR_MAINT_UTILITY:
1155		if (tcode == TCODE_READ_QUADLET_REQUEST)
1156			*data = card->maint_utility_register;
1157		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1158			card->maint_utility_register = *data;
1159		else
1160			rcode = RCODE_TYPE_ERROR;
1161		break;
1162
1163	case CSR_BROADCAST_CHANNEL:
1164		if (tcode == TCODE_READ_QUADLET_REQUEST)
1165			*data = cpu_to_be32(card->broadcast_channel);
1166		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1167			card->broadcast_channel =
1168			    (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1169			    BROADCAST_CHANNEL_INITIAL;
1170		else
1171			rcode = RCODE_TYPE_ERROR;
1172		break;
1173
1174	case CSR_BUS_MANAGER_ID:
1175	case CSR_BANDWIDTH_AVAILABLE:
1176	case CSR_CHANNELS_AVAILABLE_HI:
1177	case CSR_CHANNELS_AVAILABLE_LO:
1178		/*
1179		 * FIXME: these are handled by the OHCI hardware and
1180		 * the stack never sees these request. If we add
1181		 * support for a new type of controller that doesn't
1182		 * handle this in hardware we need to deal with these
1183		 * transactions.
1184		 */
1185		BUG();
1186		break;
1187
1188	default:
1189		rcode = RCODE_ADDRESS_ERROR;
1190		break;
1191	}
1192
1193	fw_send_response(card, request, rcode);
1194}
1195
1196static struct fw_address_handler registers = {
1197	.length			= 0x400,
1198	.address_callback	= handle_registers,
1199};
1200
1201MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1202MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1203MODULE_LICENSE("GPL");
1204
1205static const u32 vendor_textual_descriptor[] = {
1206	/* textual descriptor leaf () */
1207	0x00060000,
1208	0x00000000,
1209	0x00000000,
1210	0x4c696e75,		/* L i n u */
1211	0x78204669,		/* x   F i */
1212	0x72657769,		/* r e w i */
1213	0x72650000,		/* r e     */
1214};
1215
1216static const u32 model_textual_descriptor[] = {
1217	/* model descriptor leaf () */
1218	0x00030000,
1219	0x00000000,
1220	0x00000000,
1221	0x4a756a75,		/* J u j u */
1222};
1223
1224static struct fw_descriptor vendor_id_descriptor = {
1225	.length = ARRAY_SIZE(vendor_textual_descriptor),
1226	.immediate = 0x03d00d1e,
1227	.key = 0x81000000,
1228	.data = vendor_textual_descriptor,
1229};
1230
1231static struct fw_descriptor model_id_descriptor = {
1232	.length = ARRAY_SIZE(model_textual_descriptor),
1233	.immediate = 0x17000001,
1234	.key = 0x81000000,
1235	.data = model_textual_descriptor,
1236};
1237
1238static int __init fw_core_init(void)
1239{
1240	int ret;
1241
1242	fw_workqueue = alloc_workqueue("firewire",
1243				       WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0);
1244	if (!fw_workqueue)
1245		return -ENOMEM;
1246
1247	ret = bus_register(&fw_bus_type);
1248	if (ret < 0) {
1249		destroy_workqueue(fw_workqueue);
1250		return ret;
1251	}
1252
1253	fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1254	if (fw_cdev_major < 0) {
1255		bus_unregister(&fw_bus_type);
1256		destroy_workqueue(fw_workqueue);
1257		return fw_cdev_major;
1258	}
1259
1260	fw_core_add_address_handler(&topology_map, &topology_map_region);
1261	fw_core_add_address_handler(&registers, &registers_region);
1262	fw_core_add_descriptor(&vendor_id_descriptor);
1263	fw_core_add_descriptor(&model_id_descriptor);
1264
1265	return 0;
1266}
1267
1268static void __exit fw_core_cleanup(void)
1269{
1270	unregister_chrdev(fw_cdev_major, "firewire");
1271	bus_unregister(&fw_bus_type);
1272	destroy_workqueue(fw_workqueue);
1273	idr_destroy(&fw_device_idr);
1274}
1275
1276module_init(fw_core_init);
1277module_exit(fw_core_cleanup);