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v6.8
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Freescale MPC85xx, MPC83xx DMA Engine support
   4 *
   5 * Copyright (C) 2007-2010 Freescale Semiconductor, Inc. All rights reserved.
   6 *
   7 * Author:
   8 *   Zhang Wei <wei.zhang@freescale.com>, Jul 2007
   9 *   Ebony Zhu <ebony.zhu@freescale.com>, May 2007
  10 *
  11 * Description:
  12 *   DMA engine driver for Freescale MPC8540 DMA controller, which is
  13 *   also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc.
  14 *   The support for MPC8349 DMA controller is also added.
  15 *
  16 * This driver instructs the DMA controller to issue the PCI Read Multiple
  17 * command for PCI read operations, instead of using the default PCI Read Line
  18 * command. Please be aware that this setting may result in read pre-fetching
  19 * on some platforms.
 
 
 
 
 
 
  20 */
  21
  22#include <linux/init.h>
  23#include <linux/module.h>
  24#include <linux/pci.h>
  25#include <linux/slab.h>
  26#include <linux/interrupt.h>
  27#include <linux/dmaengine.h>
  28#include <linux/delay.h>
  29#include <linux/dma-mapping.h>
  30#include <linux/dmapool.h>
  31#include <linux/of.h>
  32#include <linux/of_address.h>
  33#include <linux/of_irq.h>
  34#include <linux/platform_device.h>
  35#include <linux/fsldma.h>
  36#include "dmaengine.h"
  37#include "fsldma.h"
  38
  39#define chan_dbg(chan, fmt, arg...)					\
  40	dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg)
  41#define chan_err(chan, fmt, arg...)					\
  42	dev_err(chan->dev, "%s: " fmt, chan->name, ##arg)
  43
  44static const char msg_ld_oom[] = "No free memory for link descriptor";
  45
  46/*
  47 * Register Helpers
  48 */
  49
  50static void set_sr(struct fsldma_chan *chan, u32 val)
  51{
  52	FSL_DMA_OUT(chan, &chan->regs->sr, val, 32);
  53}
  54
  55static u32 get_sr(struct fsldma_chan *chan)
  56{
  57	return FSL_DMA_IN(chan, &chan->regs->sr, 32);
  58}
  59
  60static void set_mr(struct fsldma_chan *chan, u32 val)
  61{
  62	FSL_DMA_OUT(chan, &chan->regs->mr, val, 32);
  63}
  64
  65static u32 get_mr(struct fsldma_chan *chan)
  66{
  67	return FSL_DMA_IN(chan, &chan->regs->mr, 32);
  68}
  69
  70static void set_cdar(struct fsldma_chan *chan, dma_addr_t addr)
  71{
  72	FSL_DMA_OUT(chan, &chan->regs->cdar, addr | FSL_DMA_SNEN, 64);
  73}
  74
  75static dma_addr_t get_cdar(struct fsldma_chan *chan)
  76{
  77	return FSL_DMA_IN(chan, &chan->regs->cdar, 64) & ~FSL_DMA_SNEN;
  78}
  79
  80static void set_bcr(struct fsldma_chan *chan, u32 val)
  81{
  82	FSL_DMA_OUT(chan, &chan->regs->bcr, val, 32);
  83}
  84
  85static u32 get_bcr(struct fsldma_chan *chan)
  86{
  87	return FSL_DMA_IN(chan, &chan->regs->bcr, 32);
  88}
  89
  90/*
  91 * Descriptor Helpers
  92 */
  93
  94static void set_desc_cnt(struct fsldma_chan *chan,
  95				struct fsl_dma_ld_hw *hw, u32 count)
  96{
  97	hw->count = CPU_TO_DMA(chan, count, 32);
  98}
  99
 100static void set_desc_src(struct fsldma_chan *chan,
 101			 struct fsl_dma_ld_hw *hw, dma_addr_t src)
 102{
 103	u64 snoop_bits;
 104
 105	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
 106		? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0;
 107	hw->src_addr = CPU_TO_DMA(chan, snoop_bits | src, 64);
 108}
 109
 110static void set_desc_dst(struct fsldma_chan *chan,
 111			 struct fsl_dma_ld_hw *hw, dma_addr_t dst)
 112{
 113	u64 snoop_bits;
 114
 115	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
 116		? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0;
 117	hw->dst_addr = CPU_TO_DMA(chan, snoop_bits | dst, 64);
 118}
 119
 120static void set_desc_next(struct fsldma_chan *chan,
 121			  struct fsl_dma_ld_hw *hw, dma_addr_t next)
 122{
 123	u64 snoop_bits;
 124
 125	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
 126		? FSL_DMA_SNEN : 0;
 127	hw->next_ln_addr = CPU_TO_DMA(chan, snoop_bits | next, 64);
 128}
 129
 130static void set_ld_eol(struct fsldma_chan *chan, struct fsl_desc_sw *desc)
 131{
 132	u64 snoop_bits;
 133
 134	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
 135		? FSL_DMA_SNEN : 0;
 136
 137	desc->hw.next_ln_addr = CPU_TO_DMA(chan,
 138		DMA_TO_CPU(chan, desc->hw.next_ln_addr, 64) | FSL_DMA_EOL
 139			| snoop_bits, 64);
 140}
 141
 142/*
 143 * DMA Engine Hardware Control Helpers
 144 */
 145
 146static void dma_init(struct fsldma_chan *chan)
 147{
 148	/* Reset the channel */
 149	set_mr(chan, 0);
 150
 151	switch (chan->feature & FSL_DMA_IP_MASK) {
 152	case FSL_DMA_IP_85XX:
 153		/* Set the channel to below modes:
 154		 * EIE - Error interrupt enable
 155		 * EOLNIE - End of links interrupt enable
 156		 * BWC - Bandwidth sharing among channels
 157		 */
 158		set_mr(chan, FSL_DMA_MR_BWC | FSL_DMA_MR_EIE
 159			| FSL_DMA_MR_EOLNIE);
 160		break;
 161	case FSL_DMA_IP_83XX:
 162		/* Set the channel to below modes:
 163		 * EOTIE - End-of-transfer interrupt enable
 164		 * PRC_RM - PCI read multiple
 165		 */
 166		set_mr(chan, FSL_DMA_MR_EOTIE | FSL_DMA_MR_PRC_RM);
 
 167		break;
 168	}
 169}
 170
 171static int dma_is_idle(struct fsldma_chan *chan)
 172{
 173	u32 sr = get_sr(chan);
 174	return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH);
 175}
 176
 177/*
 178 * Start the DMA controller
 179 *
 180 * Preconditions:
 181 * - the CDAR register must point to the start descriptor
 182 * - the MRn[CS] bit must be cleared
 183 */
 184static void dma_start(struct fsldma_chan *chan)
 185{
 186	u32 mode;
 187
 188	mode = get_mr(chan);
 189
 190	if (chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
 191		set_bcr(chan, 0);
 192		mode |= FSL_DMA_MR_EMP_EN;
 193	} else {
 194		mode &= ~FSL_DMA_MR_EMP_EN;
 195	}
 196
 197	if (chan->feature & FSL_DMA_CHAN_START_EXT) {
 198		mode |= FSL_DMA_MR_EMS_EN;
 199	} else {
 200		mode &= ~FSL_DMA_MR_EMS_EN;
 201		mode |= FSL_DMA_MR_CS;
 202	}
 203
 204	set_mr(chan, mode);
 205}
 206
 207static void dma_halt(struct fsldma_chan *chan)
 208{
 209	u32 mode;
 210	int i;
 211
 212	/* read the mode register */
 213	mode = get_mr(chan);
 214
 215	/*
 216	 * The 85xx controller supports channel abort, which will stop
 217	 * the current transfer. On 83xx, this bit is the transfer error
 218	 * mask bit, which should not be changed.
 219	 */
 220	if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) {
 221		mode |= FSL_DMA_MR_CA;
 222		set_mr(chan, mode);
 223
 224		mode &= ~FSL_DMA_MR_CA;
 225	}
 226
 227	/* stop the DMA controller */
 228	mode &= ~(FSL_DMA_MR_CS | FSL_DMA_MR_EMS_EN);
 229	set_mr(chan, mode);
 230
 231	/* wait for the DMA controller to become idle */
 232	for (i = 0; i < 100; i++) {
 233		if (dma_is_idle(chan))
 234			return;
 235
 236		udelay(10);
 237	}
 238
 239	if (!dma_is_idle(chan))
 240		chan_err(chan, "DMA halt timeout!\n");
 241}
 242
 243/**
 244 * fsl_chan_set_src_loop_size - Set source address hold transfer size
 245 * @chan : Freescale DMA channel
 246 * @size     : Address loop size, 0 for disable loop
 247 *
 248 * The set source address hold transfer size. The source
 249 * address hold or loop transfer size is when the DMA transfer
 250 * data from source address (SA), if the loop size is 4, the DMA will
 251 * read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA,
 252 * SA + 1 ... and so on.
 253 */
 254static void fsl_chan_set_src_loop_size(struct fsldma_chan *chan, int size)
 255{
 256	u32 mode;
 257
 258	mode = get_mr(chan);
 259
 260	switch (size) {
 261	case 0:
 262		mode &= ~FSL_DMA_MR_SAHE;
 263		break;
 264	case 1:
 265	case 2:
 266	case 4:
 267	case 8:
 268		mode &= ~FSL_DMA_MR_SAHTS_MASK;
 269		mode |= FSL_DMA_MR_SAHE | (__ilog2(size) << 14);
 270		break;
 271	}
 272
 273	set_mr(chan, mode);
 274}
 275
 276/**
 277 * fsl_chan_set_dst_loop_size - Set destination address hold transfer size
 278 * @chan : Freescale DMA channel
 279 * @size     : Address loop size, 0 for disable loop
 280 *
 281 * The set destination address hold transfer size. The destination
 282 * address hold or loop transfer size is when the DMA transfer
 283 * data to destination address (TA), if the loop size is 4, the DMA will
 284 * write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA,
 285 * TA + 1 ... and so on.
 286 */
 287static void fsl_chan_set_dst_loop_size(struct fsldma_chan *chan, int size)
 288{
 289	u32 mode;
 290
 291	mode = get_mr(chan);
 292
 293	switch (size) {
 294	case 0:
 295		mode &= ~FSL_DMA_MR_DAHE;
 296		break;
 297	case 1:
 298	case 2:
 299	case 4:
 300	case 8:
 301		mode &= ~FSL_DMA_MR_DAHTS_MASK;
 302		mode |= FSL_DMA_MR_DAHE | (__ilog2(size) << 16);
 303		break;
 304	}
 305
 306	set_mr(chan, mode);
 307}
 308
 309/**
 310 * fsl_chan_set_request_count - Set DMA Request Count for external control
 311 * @chan : Freescale DMA channel
 312 * @size     : Number of bytes to transfer in a single request
 313 *
 314 * The Freescale DMA channel can be controlled by the external signal DREQ#.
 315 * The DMA request count is how many bytes are allowed to transfer before
 316 * pausing the channel, after which a new assertion of DREQ# resumes channel
 317 * operation.
 318 *
 319 * A size of 0 disables external pause control. The maximum size is 1024.
 320 */
 321static void fsl_chan_set_request_count(struct fsldma_chan *chan, int size)
 322{
 323	u32 mode;
 324
 325	BUG_ON(size > 1024);
 326
 327	mode = get_mr(chan);
 328	mode &= ~FSL_DMA_MR_BWC_MASK;
 329	mode |= (__ilog2(size) << 24) & FSL_DMA_MR_BWC_MASK;
 330
 331	set_mr(chan, mode);
 332}
 333
 334/**
 335 * fsl_chan_toggle_ext_pause - Toggle channel external pause status
 336 * @chan : Freescale DMA channel
 337 * @enable   : 0 is disabled, 1 is enabled.
 338 *
 339 * The Freescale DMA channel can be controlled by the external signal DREQ#.
 340 * The DMA Request Count feature should be used in addition to this feature
 341 * to set the number of bytes to transfer before pausing the channel.
 342 */
 343static void fsl_chan_toggle_ext_pause(struct fsldma_chan *chan, int enable)
 344{
 345	if (enable)
 346		chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
 347	else
 348		chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
 349}
 350
 351/**
 352 * fsl_chan_toggle_ext_start - Toggle channel external start status
 353 * @chan : Freescale DMA channel
 354 * @enable   : 0 is disabled, 1 is enabled.
 355 *
 356 * If enable the external start, the channel can be started by an
 357 * external DMA start pin. So the dma_start() does not start the
 358 * transfer immediately. The DMA channel will wait for the
 359 * control pin asserted.
 360 */
 361static void fsl_chan_toggle_ext_start(struct fsldma_chan *chan, int enable)
 362{
 363	if (enable)
 364		chan->feature |= FSL_DMA_CHAN_START_EXT;
 365	else
 366		chan->feature &= ~FSL_DMA_CHAN_START_EXT;
 367}
 368
 369int fsl_dma_external_start(struct dma_chan *dchan, int enable)
 370{
 371	struct fsldma_chan *chan;
 372
 373	if (!dchan)
 374		return -EINVAL;
 375
 376	chan = to_fsl_chan(dchan);
 377
 378	fsl_chan_toggle_ext_start(chan, enable);
 379	return 0;
 380}
 381EXPORT_SYMBOL_GPL(fsl_dma_external_start);
 382
 383static void append_ld_queue(struct fsldma_chan *chan, struct fsl_desc_sw *desc)
 384{
 385	struct fsl_desc_sw *tail = to_fsl_desc(chan->ld_pending.prev);
 386
 387	if (list_empty(&chan->ld_pending))
 388		goto out_splice;
 389
 390	/*
 391	 * Add the hardware descriptor to the chain of hardware descriptors
 392	 * that already exists in memory.
 393	 *
 394	 * This will un-set the EOL bit of the existing transaction, and the
 395	 * last link in this transaction will become the EOL descriptor.
 396	 */
 397	set_desc_next(chan, &tail->hw, desc->async_tx.phys);
 398
 399	/*
 400	 * Add the software descriptor and all children to the list
 401	 * of pending transactions
 402	 */
 403out_splice:
 404	list_splice_tail_init(&desc->tx_list, &chan->ld_pending);
 405}
 406
 407static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 408{
 409	struct fsldma_chan *chan = to_fsl_chan(tx->chan);
 410	struct fsl_desc_sw *desc = tx_to_fsl_desc(tx);
 411	struct fsl_desc_sw *child;
 
 412	dma_cookie_t cookie = -EINVAL;
 413
 414	spin_lock_bh(&chan->desc_lock);
 415
 416#ifdef CONFIG_PM
 417	if (unlikely(chan->pm_state != RUNNING)) {
 418		chan_dbg(chan, "cannot submit due to suspend\n");
 419		spin_unlock_bh(&chan->desc_lock);
 420		return -1;
 421	}
 422#endif
 423
 424	/*
 425	 * assign cookies to all of the software descriptors
 426	 * that make up this transaction
 427	 */
 428	list_for_each_entry(child, &desc->tx_list, node) {
 429		cookie = dma_cookie_assign(&child->async_tx);
 430	}
 431
 432	/* put this transaction onto the tail of the pending queue */
 433	append_ld_queue(chan, desc);
 434
 435	spin_unlock_bh(&chan->desc_lock);
 436
 437	return cookie;
 438}
 439
 440/**
 441 * fsl_dma_free_descriptor - Free descriptor from channel's DMA pool.
 442 * @chan : Freescale DMA channel
 443 * @desc: descriptor to be freed
 444 */
 445static void fsl_dma_free_descriptor(struct fsldma_chan *chan,
 446		struct fsl_desc_sw *desc)
 447{
 448	list_del(&desc->node);
 449	chan_dbg(chan, "LD %p free\n", desc);
 450	dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
 451}
 452
 453/**
 454 * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool.
 455 * @chan : Freescale DMA channel
 456 *
 457 * Return - The descriptor allocated. NULL for failed.
 458 */
 459static struct fsl_desc_sw *fsl_dma_alloc_descriptor(struct fsldma_chan *chan)
 460{
 461	struct fsl_desc_sw *desc;
 462	dma_addr_t pdesc;
 463
 464	desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &pdesc);
 465	if (!desc) {
 466		chan_dbg(chan, "out of memory for link descriptor\n");
 467		return NULL;
 468	}
 469
 
 470	INIT_LIST_HEAD(&desc->tx_list);
 471	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
 472	desc->async_tx.tx_submit = fsl_dma_tx_submit;
 473	desc->async_tx.phys = pdesc;
 474
 
 475	chan_dbg(chan, "LD %p allocated\n", desc);
 
 476
 477	return desc;
 478}
 479
 480/**
 481 * fsldma_clean_completed_descriptor - free all descriptors which
 482 * has been completed and acked
 483 * @chan: Freescale DMA channel
 484 *
 485 * This function is used on all completed and acked descriptors.
 486 * All descriptors should only be freed in this function.
 487 */
 488static void fsldma_clean_completed_descriptor(struct fsldma_chan *chan)
 489{
 490	struct fsl_desc_sw *desc, *_desc;
 491
 492	/* Run the callback for each descriptor, in order */
 493	list_for_each_entry_safe(desc, _desc, &chan->ld_completed, node)
 494		if (async_tx_test_ack(&desc->async_tx))
 495			fsl_dma_free_descriptor(chan, desc);
 496}
 497
 498/**
 499 * fsldma_run_tx_complete_actions - cleanup a single link descriptor
 500 * @chan: Freescale DMA channel
 501 * @desc: descriptor to cleanup and free
 502 * @cookie: Freescale DMA transaction identifier
 503 *
 504 * This function is used on a descriptor which has been executed by the DMA
 505 * controller. It will run any callbacks, submit any dependencies.
 506 */
 507static dma_cookie_t fsldma_run_tx_complete_actions(struct fsldma_chan *chan,
 508		struct fsl_desc_sw *desc, dma_cookie_t cookie)
 509{
 510	struct dma_async_tx_descriptor *txd = &desc->async_tx;
 511	dma_cookie_t ret = cookie;
 512
 513	BUG_ON(txd->cookie < 0);
 514
 515	if (txd->cookie > 0) {
 516		ret = txd->cookie;
 517
 518		dma_descriptor_unmap(txd);
 519		/* Run the link descriptor callback function */
 520		dmaengine_desc_get_callback_invoke(txd, NULL);
 521	}
 522
 523	/* Run any dependencies */
 524	dma_run_dependencies(txd);
 525
 526	return ret;
 527}
 528
 529/**
 530 * fsldma_clean_running_descriptor - move the completed descriptor from
 531 * ld_running to ld_completed
 532 * @chan: Freescale DMA channel
 533 * @desc: the descriptor which is completed
 534 *
 535 * Free the descriptor directly if acked by async_tx api, or move it to
 536 * queue ld_completed.
 537 */
 538static void fsldma_clean_running_descriptor(struct fsldma_chan *chan,
 539		struct fsl_desc_sw *desc)
 540{
 541	/* Remove from the list of transactions */
 542	list_del(&desc->node);
 543
 544	/*
 545	 * the client is allowed to attach dependent operations
 546	 * until 'ack' is set
 547	 */
 548	if (!async_tx_test_ack(&desc->async_tx)) {
 549		/*
 550		 * Move this descriptor to the list of descriptors which is
 551		 * completed, but still awaiting the 'ack' bit to be set.
 552		 */
 553		list_add_tail(&desc->node, &chan->ld_completed);
 554		return;
 555	}
 556
 557	dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
 558}
 559
 560/**
 561 * fsl_chan_xfer_ld_queue - transfer any pending transactions
 562 * @chan : Freescale DMA channel
 563 *
 564 * HARDWARE STATE: idle
 565 * LOCKING: must hold chan->desc_lock
 566 */
 567static void fsl_chan_xfer_ld_queue(struct fsldma_chan *chan)
 568{
 569	struct fsl_desc_sw *desc;
 570
 571	/*
 572	 * If the list of pending descriptors is empty, then we
 573	 * don't need to do any work at all
 574	 */
 575	if (list_empty(&chan->ld_pending)) {
 576		chan_dbg(chan, "no pending LDs\n");
 577		return;
 578	}
 579
 580	/*
 581	 * The DMA controller is not idle, which means that the interrupt
 582	 * handler will start any queued transactions when it runs after
 583	 * this transaction finishes
 584	 */
 585	if (!chan->idle) {
 586		chan_dbg(chan, "DMA controller still busy\n");
 587		return;
 588	}
 589
 590	/*
 591	 * If there are some link descriptors which have not been
 592	 * transferred, we need to start the controller
 593	 */
 594
 595	/*
 596	 * Move all elements from the queue of pending transactions
 597	 * onto the list of running transactions
 598	 */
 599	chan_dbg(chan, "idle, starting controller\n");
 600	desc = list_first_entry(&chan->ld_pending, struct fsl_desc_sw, node);
 601	list_splice_tail_init(&chan->ld_pending, &chan->ld_running);
 602
 603	/*
 604	 * The 85xx DMA controller doesn't clear the channel start bit
 605	 * automatically at the end of a transfer. Therefore we must clear
 606	 * it in software before starting the transfer.
 607	 */
 608	if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) {
 609		u32 mode;
 610
 611		mode = get_mr(chan);
 612		mode &= ~FSL_DMA_MR_CS;
 613		set_mr(chan, mode);
 614	}
 615
 616	/*
 617	 * Program the descriptor's address into the DMA controller,
 618	 * then start the DMA transaction
 619	 */
 620	set_cdar(chan, desc->async_tx.phys);
 621	get_cdar(chan);
 622
 623	dma_start(chan);
 624	chan->idle = false;
 625}
 626
 627/**
 628 * fsldma_cleanup_descriptors - cleanup link descriptors which are completed
 629 * and move them to ld_completed to free until flag 'ack' is set
 630 * @chan: Freescale DMA channel
 631 *
 632 * This function is used on descriptors which have been executed by the DMA
 633 * controller. It will run any callbacks, submit any dependencies, then
 634 * free these descriptors if flag 'ack' is set.
 635 */
 636static void fsldma_cleanup_descriptors(struct fsldma_chan *chan)
 637{
 638	struct fsl_desc_sw *desc, *_desc;
 639	dma_cookie_t cookie = 0;
 640	dma_addr_t curr_phys = get_cdar(chan);
 641	int seen_current = 0;
 642
 643	fsldma_clean_completed_descriptor(chan);
 644
 645	/* Run the callback for each descriptor, in order */
 646	list_for_each_entry_safe(desc, _desc, &chan->ld_running, node) {
 647		/*
 648		 * do not advance past the current descriptor loaded into the
 649		 * hardware channel, subsequent descriptors are either in
 650		 * process or have not been submitted
 651		 */
 652		if (seen_current)
 653			break;
 654
 655		/*
 656		 * stop the search if we reach the current descriptor and the
 657		 * channel is busy
 658		 */
 659		if (desc->async_tx.phys == curr_phys) {
 660			seen_current = 1;
 661			if (!dma_is_idle(chan))
 662				break;
 663		}
 664
 665		cookie = fsldma_run_tx_complete_actions(chan, desc, cookie);
 666
 667		fsldma_clean_running_descriptor(chan, desc);
 668	}
 669
 670	/*
 671	 * Start any pending transactions automatically
 672	 *
 673	 * In the ideal case, we keep the DMA controller busy while we go
 674	 * ahead and free the descriptors below.
 675	 */
 676	fsl_chan_xfer_ld_queue(chan);
 677
 678	if (cookie > 0)
 679		chan->common.completed_cookie = cookie;
 680}
 681
 682/**
 683 * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel.
 684 * @chan : Freescale DMA channel
 685 *
 686 * This function will create a dma pool for descriptor allocation.
 687 *
 688 * Return - The number of descriptors allocated.
 689 */
 690static int fsl_dma_alloc_chan_resources(struct dma_chan *dchan)
 691{
 692	struct fsldma_chan *chan = to_fsl_chan(dchan);
 693
 694	/* Has this channel already been allocated? */
 695	if (chan->desc_pool)
 696		return 1;
 697
 698	/*
 699	 * We need the descriptor to be aligned to 32bytes
 700	 * for meeting FSL DMA specification requirement.
 701	 */
 702	chan->desc_pool = dma_pool_create(chan->name, chan->dev,
 703					  sizeof(struct fsl_desc_sw),
 704					  __alignof__(struct fsl_desc_sw), 0);
 705	if (!chan->desc_pool) {
 706		chan_err(chan, "unable to allocate descriptor pool\n");
 707		return -ENOMEM;
 708	}
 709
 710	/* there is at least one descriptor free to be allocated */
 711	return 1;
 712}
 713
 714/**
 715 * fsldma_free_desc_list - Free all descriptors in a queue
 716 * @chan: Freescae DMA channel
 717 * @list: the list to free
 718 *
 719 * LOCKING: must hold chan->desc_lock
 720 */
 721static void fsldma_free_desc_list(struct fsldma_chan *chan,
 722				  struct list_head *list)
 723{
 724	struct fsl_desc_sw *desc, *_desc;
 725
 726	list_for_each_entry_safe(desc, _desc, list, node)
 727		fsl_dma_free_descriptor(chan, desc);
 
 
 
 
 
 728}
 729
 730static void fsldma_free_desc_list_reverse(struct fsldma_chan *chan,
 731					  struct list_head *list)
 732{
 733	struct fsl_desc_sw *desc, *_desc;
 734
 735	list_for_each_entry_safe_reverse(desc, _desc, list, node)
 736		fsl_dma_free_descriptor(chan, desc);
 
 
 
 
 
 737}
 738
 739/**
 740 * fsl_dma_free_chan_resources - Free all resources of the channel.
 741 * @chan : Freescale DMA channel
 742 */
 743static void fsl_dma_free_chan_resources(struct dma_chan *dchan)
 744{
 745	struct fsldma_chan *chan = to_fsl_chan(dchan);
 
 746
 747	chan_dbg(chan, "free all channel resources\n");
 748	spin_lock_bh(&chan->desc_lock);
 749	fsldma_cleanup_descriptors(chan);
 750	fsldma_free_desc_list(chan, &chan->ld_pending);
 751	fsldma_free_desc_list(chan, &chan->ld_running);
 752	fsldma_free_desc_list(chan, &chan->ld_completed);
 753	spin_unlock_bh(&chan->desc_lock);
 754
 755	dma_pool_destroy(chan->desc_pool);
 756	chan->desc_pool = NULL;
 757}
 758
 759static struct dma_async_tx_descriptor *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 760fsl_dma_prep_memcpy(struct dma_chan *dchan,
 761	dma_addr_t dma_dst, dma_addr_t dma_src,
 762	size_t len, unsigned long flags)
 763{
 764	struct fsldma_chan *chan;
 765	struct fsl_desc_sw *first = NULL, *prev = NULL, *new;
 766	size_t copy;
 767
 768	if (!dchan)
 769		return NULL;
 770
 771	if (!len)
 772		return NULL;
 773
 774	chan = to_fsl_chan(dchan);
 775
 776	do {
 777
 778		/* Allocate the link descriptor from DMA pool */
 779		new = fsl_dma_alloc_descriptor(chan);
 780		if (!new) {
 781			chan_err(chan, "%s\n", msg_ld_oom);
 782			goto fail;
 783		}
 784
 785		copy = min(len, (size_t)FSL_DMA_BCR_MAX_CNT);
 786
 787		set_desc_cnt(chan, &new->hw, copy);
 788		set_desc_src(chan, &new->hw, dma_src);
 789		set_desc_dst(chan, &new->hw, dma_dst);
 790
 791		if (!first)
 792			first = new;
 793		else
 794			set_desc_next(chan, &prev->hw, new->async_tx.phys);
 795
 796		new->async_tx.cookie = 0;
 797		async_tx_ack(&new->async_tx);
 798
 799		prev = new;
 800		len -= copy;
 801		dma_src += copy;
 802		dma_dst += copy;
 803
 804		/* Insert the link descriptor to the LD ring */
 805		list_add_tail(&new->node, &first->tx_list);
 806	} while (len);
 807
 808	new->async_tx.flags = flags; /* client is in control of this ack */
 809	new->async_tx.cookie = -EBUSY;
 810
 811	/* Set End-of-link to the last link descriptor of new list */
 812	set_ld_eol(chan, new);
 813
 814	return &first->async_tx;
 815
 816fail:
 817	if (!first)
 818		return NULL;
 819
 820	fsldma_free_desc_list_reverse(chan, &first->tx_list);
 821	return NULL;
 822}
 823
 824static int fsl_dma_device_terminate_all(struct dma_chan *dchan)
 
 
 
 825{
 826	struct fsldma_chan *chan;
 
 
 
 
 827
 828	if (!dchan)
 829		return -EINVAL;
 
 830
 831	chan = to_fsl_chan(dchan);
 
 832
 833	spin_lock_bh(&chan->desc_lock);
 
 
 
 834
 835	/* Halt the DMA engine */
 836	dma_halt(chan);
 
 
 
 
 
 
 
 
 
 
 837
 838	/* Remove and free all of the descriptors in the LD queue */
 839	fsldma_free_desc_list(chan, &chan->ld_pending);
 840	fsldma_free_desc_list(chan, &chan->ld_running);
 841	fsldma_free_desc_list(chan, &chan->ld_completed);
 842	chan->idle = true;
 843
 844	spin_unlock_bh(&chan->desc_lock);
 845	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 846}
 847
 848static int fsl_dma_device_config(struct dma_chan *dchan,
 849				 struct dma_slave_config *config)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 850{
 
 
 
 
 
 
 
 
 
 
 
 
 
 851	struct fsldma_chan *chan;
 
 852	int size;
 853
 854	if (!dchan)
 855		return -EINVAL;
 856
 857	chan = to_fsl_chan(dchan);
 858
 859	/* make sure the channel supports setting burst size */
 860	if (!chan->set_request_count)
 861		return -ENXIO;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 862
 863	/* we set the controller burst size depending on direction */
 864	if (config->direction == DMA_MEM_TO_DEV)
 865		size = config->dst_addr_width * config->dst_maxburst;
 866	else
 867		size = config->src_addr_width * config->src_maxburst;
 
 
 
 
 
 
 
 
 
 
 868
 869	chan->set_request_count(chan, size);
 870	return 0;
 871}
 872
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 873
 874/**
 875 * fsl_dma_memcpy_issue_pending - Issue the DMA start command
 876 * @chan : Freescale DMA channel
 877 */
 878static void fsl_dma_memcpy_issue_pending(struct dma_chan *dchan)
 879{
 880	struct fsldma_chan *chan = to_fsl_chan(dchan);
 
 881
 882	spin_lock_bh(&chan->desc_lock);
 883	fsl_chan_xfer_ld_queue(chan);
 884	spin_unlock_bh(&chan->desc_lock);
 885}
 886
 887/**
 888 * fsl_tx_status - Determine the DMA status
 889 * @chan : Freescale DMA channel
 890 */
 891static enum dma_status fsl_tx_status(struct dma_chan *dchan,
 892					dma_cookie_t cookie,
 893					struct dma_tx_state *txstate)
 894{
 895	struct fsldma_chan *chan = to_fsl_chan(dchan);
 896	enum dma_status ret;
 897
 898	ret = dma_cookie_status(dchan, cookie, txstate);
 899	if (ret == DMA_COMPLETE)
 900		return ret;
 901
 902	spin_lock_bh(&chan->desc_lock);
 903	fsldma_cleanup_descriptors(chan);
 904	spin_unlock_bh(&chan->desc_lock);
 905
 906	return dma_cookie_status(dchan, cookie, txstate);
 907}
 908
 909/*----------------------------------------------------------------------------*/
 910/* Interrupt Handling                                                         */
 911/*----------------------------------------------------------------------------*/
 912
 913static irqreturn_t fsldma_chan_irq(int irq, void *data)
 914{
 915	struct fsldma_chan *chan = data;
 916	u32 stat;
 917
 918	/* save and clear the status register */
 919	stat = get_sr(chan);
 920	set_sr(chan, stat);
 921	chan_dbg(chan, "irq: stat = 0x%x\n", stat);
 922
 923	/* check that this was really our device */
 924	stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH);
 925	if (!stat)
 926		return IRQ_NONE;
 927
 928	if (stat & FSL_DMA_SR_TE)
 929		chan_err(chan, "Transfer Error!\n");
 930
 931	/*
 932	 * Programming Error
 933	 * The DMA_INTERRUPT async_tx is a NULL transfer, which will
 934	 * trigger a PE interrupt.
 935	 */
 936	if (stat & FSL_DMA_SR_PE) {
 937		chan_dbg(chan, "irq: Programming Error INT\n");
 938		stat &= ~FSL_DMA_SR_PE;
 939		if (get_bcr(chan) != 0)
 940			chan_err(chan, "Programming Error!\n");
 941	}
 942
 943	/*
 944	 * For MPC8349, EOCDI event need to update cookie
 945	 * and start the next transfer if it exist.
 946	 */
 947	if (stat & FSL_DMA_SR_EOCDI) {
 948		chan_dbg(chan, "irq: End-of-Chain link INT\n");
 949		stat &= ~FSL_DMA_SR_EOCDI;
 950	}
 951
 952	/*
 953	 * If it current transfer is the end-of-transfer,
 954	 * we should clear the Channel Start bit for
 955	 * prepare next transfer.
 956	 */
 957	if (stat & FSL_DMA_SR_EOLNI) {
 958		chan_dbg(chan, "irq: End-of-link INT\n");
 959		stat &= ~FSL_DMA_SR_EOLNI;
 960	}
 961
 962	/* check that the DMA controller is really idle */
 963	if (!dma_is_idle(chan))
 964		chan_err(chan, "irq: controller not idle!\n");
 965
 966	/* check that we handled all of the bits */
 967	if (stat)
 968		chan_err(chan, "irq: unhandled sr 0x%08x\n", stat);
 969
 970	/*
 971	 * Schedule the tasklet to handle all cleanup of the current
 972	 * transaction. It will start a new transaction if there is
 973	 * one pending.
 974	 */
 975	tasklet_schedule(&chan->tasklet);
 976	chan_dbg(chan, "irq: Exit\n");
 977	return IRQ_HANDLED;
 978}
 979
 980static void dma_do_tasklet(struct tasklet_struct *t)
 981{
 982	struct fsldma_chan *chan = from_tasklet(chan, t, tasklet);
 
 
 
 983
 984	chan_dbg(chan, "tasklet entry\n");
 985
 986	spin_lock(&chan->desc_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 987
 988	/* the hardware is now idle and ready for more */
 989	chan->idle = true;
 990
 991	/* Run all cleanup for descriptors which have been completed */
 992	fsldma_cleanup_descriptors(chan);
 
 
 
 
 
 
 
 
 
 
 
 
 993
 994	spin_unlock(&chan->desc_lock);
 
 
 995
 996	chan_dbg(chan, "tasklet exit\n");
 997}
 998
 999static irqreturn_t fsldma_ctrl_irq(int irq, void *data)
1000{
1001	struct fsldma_device *fdev = data;
1002	struct fsldma_chan *chan;
1003	unsigned int handled = 0;
1004	u32 gsr, mask;
1005	int i;
1006
1007	gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs)
1008						   : in_le32(fdev->regs);
1009	mask = 0xff000000;
1010	dev_dbg(fdev->dev, "IRQ: gsr 0x%.8x\n", gsr);
1011
1012	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1013		chan = fdev->chan[i];
1014		if (!chan)
1015			continue;
1016
1017		if (gsr & mask) {
1018			dev_dbg(fdev->dev, "IRQ: chan %d\n", chan->id);
1019			fsldma_chan_irq(irq, chan);
1020			handled++;
1021		}
1022
1023		gsr &= ~mask;
1024		mask >>= 8;
1025	}
1026
1027	return IRQ_RETVAL(handled);
1028}
1029
1030static void fsldma_free_irqs(struct fsldma_device *fdev)
1031{
1032	struct fsldma_chan *chan;
1033	int i;
1034
1035	if (fdev->irq) {
1036		dev_dbg(fdev->dev, "free per-controller IRQ\n");
1037		free_irq(fdev->irq, fdev);
1038		return;
1039	}
1040
1041	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1042		chan = fdev->chan[i];
1043		if (chan && chan->irq) {
1044			chan_dbg(chan, "free per-channel IRQ\n");
1045			free_irq(chan->irq, chan);
1046		}
1047	}
1048}
1049
1050static int fsldma_request_irqs(struct fsldma_device *fdev)
1051{
1052	struct fsldma_chan *chan;
1053	int ret;
1054	int i;
1055
1056	/* if we have a per-controller IRQ, use that */
1057	if (fdev->irq) {
1058		dev_dbg(fdev->dev, "request per-controller IRQ\n");
1059		ret = request_irq(fdev->irq, fsldma_ctrl_irq, IRQF_SHARED,
1060				  "fsldma-controller", fdev);
1061		return ret;
1062	}
1063
1064	/* no per-controller IRQ, use the per-channel IRQs */
1065	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1066		chan = fdev->chan[i];
1067		if (!chan)
1068			continue;
1069
1070		if (!chan->irq) {
1071			chan_err(chan, "interrupts property missing in device tree\n");
1072			ret = -ENODEV;
1073			goto out_unwind;
1074		}
1075
1076		chan_dbg(chan, "request per-channel IRQ\n");
1077		ret = request_irq(chan->irq, fsldma_chan_irq, IRQF_SHARED,
1078				  "fsldma-chan", chan);
1079		if (ret) {
1080			chan_err(chan, "unable to request per-channel IRQ\n");
1081			goto out_unwind;
1082		}
1083	}
1084
1085	return 0;
1086
1087out_unwind:
1088	for (/* none */; i >= 0; i--) {
1089		chan = fdev->chan[i];
1090		if (!chan)
1091			continue;
1092
1093		if (!chan->irq)
1094			continue;
1095
1096		free_irq(chan->irq, chan);
1097	}
1098
1099	return ret;
1100}
1101
1102/*----------------------------------------------------------------------------*/
1103/* OpenFirmware Subsystem                                                     */
1104/*----------------------------------------------------------------------------*/
1105
1106static int fsl_dma_chan_probe(struct fsldma_device *fdev,
1107	struct device_node *node, u32 feature, const char *compatible)
1108{
1109	struct fsldma_chan *chan;
1110	struct resource res;
1111	int err;
1112
1113	/* alloc channel */
1114	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1115	if (!chan) {
 
1116		err = -ENOMEM;
1117		goto out_return;
1118	}
1119
1120	/* ioremap registers for use */
1121	chan->regs = of_iomap(node, 0);
1122	if (!chan->regs) {
1123		dev_err(fdev->dev, "unable to ioremap registers\n");
1124		err = -ENOMEM;
1125		goto out_free_chan;
1126	}
1127
1128	err = of_address_to_resource(node, 0, &res);
1129	if (err) {
1130		dev_err(fdev->dev, "unable to find 'reg' property\n");
1131		goto out_iounmap_regs;
1132	}
1133
1134	chan->feature = feature;
1135	if (!fdev->feature)
1136		fdev->feature = chan->feature;
1137
1138	/*
1139	 * If the DMA device's feature is different than the feature
1140	 * of its channels, report the bug
1141	 */
1142	WARN_ON(fdev->feature != chan->feature);
1143
1144	chan->dev = fdev->dev;
1145	chan->id = (res.start & 0xfff) < 0x300 ?
1146		   ((res.start - 0x100) & 0xfff) >> 7 :
1147		   ((res.start - 0x200) & 0xfff) >> 7;
1148	if (chan->id >= FSL_DMA_MAX_CHANS_PER_DEVICE) {
1149		dev_err(fdev->dev, "too many channels for device\n");
1150		err = -EINVAL;
1151		goto out_iounmap_regs;
1152	}
1153
1154	fdev->chan[chan->id] = chan;
1155	tasklet_setup(&chan->tasklet, dma_do_tasklet);
1156	snprintf(chan->name, sizeof(chan->name), "chan%d", chan->id);
1157
1158	/* Initialize the channel */
1159	dma_init(chan);
1160
1161	/* Clear cdar registers */
1162	set_cdar(chan, 0);
1163
1164	switch (chan->feature & FSL_DMA_IP_MASK) {
1165	case FSL_DMA_IP_85XX:
1166		chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
1167		fallthrough;
1168	case FSL_DMA_IP_83XX:
1169		chan->toggle_ext_start = fsl_chan_toggle_ext_start;
1170		chan->set_src_loop_size = fsl_chan_set_src_loop_size;
1171		chan->set_dst_loop_size = fsl_chan_set_dst_loop_size;
1172		chan->set_request_count = fsl_chan_set_request_count;
1173	}
1174
1175	spin_lock_init(&chan->desc_lock);
1176	INIT_LIST_HEAD(&chan->ld_pending);
1177	INIT_LIST_HEAD(&chan->ld_running);
1178	INIT_LIST_HEAD(&chan->ld_completed);
1179	chan->idle = true;
1180#ifdef CONFIG_PM
1181	chan->pm_state = RUNNING;
1182#endif
1183
1184	chan->common.device = &fdev->common;
1185	dma_cookie_init(&chan->common);
1186
1187	/* find the IRQ line, if it exists in the device tree */
1188	chan->irq = irq_of_parse_and_map(node, 0);
1189
1190	/* Add the channel to DMA device channel list */
1191	list_add_tail(&chan->common.device_node, &fdev->common.channels);
 
1192
1193	dev_info(fdev->dev, "#%d (%s), irq %d\n", chan->id, compatible,
1194		 chan->irq ? chan->irq : fdev->irq);
1195
1196	return 0;
1197
1198out_iounmap_regs:
1199	iounmap(chan->regs);
1200out_free_chan:
1201	kfree(chan);
1202out_return:
1203	return err;
1204}
1205
1206static void fsl_dma_chan_remove(struct fsldma_chan *chan)
1207{
1208	irq_dispose_mapping(chan->irq);
1209	list_del(&chan->common.device_node);
1210	iounmap(chan->regs);
1211	kfree(chan);
1212}
1213
1214static int fsldma_of_probe(struct platform_device *op)
1215{
1216	struct fsldma_device *fdev;
1217	struct device_node *child;
1218	unsigned int i;
1219	int err;
1220
1221	fdev = kzalloc(sizeof(*fdev), GFP_KERNEL);
1222	if (!fdev) {
 
1223		err = -ENOMEM;
1224		goto out_return;
1225	}
1226
1227	fdev->dev = &op->dev;
1228	INIT_LIST_HEAD(&fdev->common.channels);
1229
1230	/* ioremap the registers for use */
1231	fdev->regs = of_iomap(op->dev.of_node, 0);
1232	if (!fdev->regs) {
1233		dev_err(&op->dev, "unable to ioremap registers\n");
1234		err = -ENOMEM;
1235		goto out_free;
1236	}
1237
1238	/* map the channel IRQ if it exists, but don't hookup the handler yet */
1239	fdev->irq = irq_of_parse_and_map(op->dev.of_node, 0);
1240
1241	dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
 
 
1242	dma_cap_set(DMA_SLAVE, fdev->common.cap_mask);
1243	fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources;
1244	fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources;
 
1245	fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
 
1246	fdev->common.device_tx_status = fsl_tx_status;
1247	fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
1248	fdev->common.device_config = fsl_dma_device_config;
1249	fdev->common.device_terminate_all = fsl_dma_device_terminate_all;
1250	fdev->common.dev = &op->dev;
1251
1252	fdev->common.src_addr_widths = FSL_DMA_BUSWIDTHS;
1253	fdev->common.dst_addr_widths = FSL_DMA_BUSWIDTHS;
1254	fdev->common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1255	fdev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1256
1257	dma_set_mask(&(op->dev), DMA_BIT_MASK(36));
1258
1259	platform_set_drvdata(op, fdev);
1260
1261	/*
1262	 * We cannot use of_platform_bus_probe() because there is no
1263	 * of_platform_bus_remove(). Instead, we manually instantiate every DMA
1264	 * channel object.
1265	 */
1266	for_each_child_of_node(op->dev.of_node, child) {
1267		if (of_device_is_compatible(child, "fsl,eloplus-dma-channel")) {
1268			fsl_dma_chan_probe(fdev, child,
1269				FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN,
1270				"fsl,eloplus-dma-channel");
1271		}
1272
1273		if (of_device_is_compatible(child, "fsl,elo-dma-channel")) {
1274			fsl_dma_chan_probe(fdev, child,
1275				FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN,
1276				"fsl,elo-dma-channel");
1277		}
1278	}
1279
1280	/*
1281	 * Hookup the IRQ handler(s)
1282	 *
1283	 * If we have a per-controller interrupt, we prefer that to the
1284	 * per-channel interrupts to reduce the number of shared interrupt
1285	 * handlers on the same IRQ line
1286	 */
1287	err = fsldma_request_irqs(fdev);
1288	if (err) {
1289		dev_err(fdev->dev, "unable to request IRQs\n");
1290		goto out_free_fdev;
1291	}
1292
1293	dma_async_device_register(&fdev->common);
1294	return 0;
1295
1296out_free_fdev:
1297	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1298		if (fdev->chan[i])
1299			fsl_dma_chan_remove(fdev->chan[i]);
1300	}
1301	irq_dispose_mapping(fdev->irq);
1302	iounmap(fdev->regs);
1303out_free:
1304	kfree(fdev);
1305out_return:
1306	return err;
1307}
1308
1309static void fsldma_of_remove(struct platform_device *op)
1310{
1311	struct fsldma_device *fdev;
1312	unsigned int i;
1313
1314	fdev = platform_get_drvdata(op);
1315	dma_async_device_unregister(&fdev->common);
1316
1317	fsldma_free_irqs(fdev);
1318
1319	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1320		if (fdev->chan[i])
1321			fsl_dma_chan_remove(fdev->chan[i]);
1322	}
1323	irq_dispose_mapping(fdev->irq);
1324
1325	iounmap(fdev->regs);
1326	kfree(fdev);
1327}
1328
1329#ifdef CONFIG_PM
1330static int fsldma_suspend_late(struct device *dev)
1331{
1332	struct fsldma_device *fdev = dev_get_drvdata(dev);
1333	struct fsldma_chan *chan;
1334	int i;
1335
1336	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1337		chan = fdev->chan[i];
1338		if (!chan)
1339			continue;
1340
1341		spin_lock_bh(&chan->desc_lock);
1342		if (unlikely(!chan->idle))
1343			goto out;
1344		chan->regs_save.mr = get_mr(chan);
1345		chan->pm_state = SUSPENDED;
1346		spin_unlock_bh(&chan->desc_lock);
1347	}
1348	return 0;
1349
1350out:
1351	for (; i >= 0; i--) {
1352		chan = fdev->chan[i];
1353		if (!chan)
1354			continue;
1355		chan->pm_state = RUNNING;
1356		spin_unlock_bh(&chan->desc_lock);
1357	}
1358	return -EBUSY;
1359}
1360
1361static int fsldma_resume_early(struct device *dev)
1362{
1363	struct fsldma_device *fdev = dev_get_drvdata(dev);
1364	struct fsldma_chan *chan;
1365	u32 mode;
1366	int i;
1367
1368	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1369		chan = fdev->chan[i];
1370		if (!chan)
1371			continue;
1372
1373		spin_lock_bh(&chan->desc_lock);
1374		mode = chan->regs_save.mr
1375			& ~FSL_DMA_MR_CS & ~FSL_DMA_MR_CC & ~FSL_DMA_MR_CA;
1376		set_mr(chan, mode);
1377		chan->pm_state = RUNNING;
1378		spin_unlock_bh(&chan->desc_lock);
1379	}
1380
1381	return 0;
1382}
1383
1384static const struct dev_pm_ops fsldma_pm_ops = {
1385	.suspend_late	= fsldma_suspend_late,
1386	.resume_early	= fsldma_resume_early,
1387};
1388#endif
1389
1390static const struct of_device_id fsldma_of_ids[] = {
1391	{ .compatible = "fsl,elo3-dma", },
1392	{ .compatible = "fsl,eloplus-dma", },
1393	{ .compatible = "fsl,elo-dma", },
1394	{}
1395};
1396MODULE_DEVICE_TABLE(of, fsldma_of_ids);
1397
1398static struct platform_driver fsldma_of_driver = {
1399	.driver = {
1400		.name = "fsl-elo-dma",
 
1401		.of_match_table = fsldma_of_ids,
1402#ifdef CONFIG_PM
1403		.pm = &fsldma_pm_ops,
1404#endif
1405	},
1406	.probe = fsldma_of_probe,
1407	.remove_new = fsldma_of_remove,
1408};
1409
1410/*----------------------------------------------------------------------------*/
1411/* Module Init / Exit                                                         */
1412/*----------------------------------------------------------------------------*/
1413
1414static __init int fsldma_init(void)
1415{
1416	pr_info("Freescale Elo series DMA driver\n");
1417	return platform_driver_register(&fsldma_of_driver);
1418}
1419
1420static void __exit fsldma_exit(void)
1421{
1422	platform_driver_unregister(&fsldma_of_driver);
1423}
1424
1425subsys_initcall(fsldma_init);
1426module_exit(fsldma_exit);
1427
1428MODULE_DESCRIPTION("Freescale Elo series DMA driver");
1429MODULE_LICENSE("GPL");
v3.15
 
   1/*
   2 * Freescale MPC85xx, MPC83xx DMA Engine support
   3 *
   4 * Copyright (C) 2007-2010 Freescale Semiconductor, Inc. All rights reserved.
   5 *
   6 * Author:
   7 *   Zhang Wei <wei.zhang@freescale.com>, Jul 2007
   8 *   Ebony Zhu <ebony.zhu@freescale.com>, May 2007
   9 *
  10 * Description:
  11 *   DMA engine driver for Freescale MPC8540 DMA controller, which is
  12 *   also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc.
  13 *   The support for MPC8349 DMA controller is also added.
  14 *
  15 * This driver instructs the DMA controller to issue the PCI Read Multiple
  16 * command for PCI read operations, instead of using the default PCI Read Line
  17 * command. Please be aware that this setting may result in read pre-fetching
  18 * on some platforms.
  19 *
  20 * This is free software; you can redistribute it and/or modify
  21 * it under the terms of the GNU General Public License as published by
  22 * the Free Software Foundation; either version 2 of the License, or
  23 * (at your option) any later version.
  24 *
  25 */
  26
  27#include <linux/init.h>
  28#include <linux/module.h>
  29#include <linux/pci.h>
  30#include <linux/slab.h>
  31#include <linux/interrupt.h>
  32#include <linux/dmaengine.h>
  33#include <linux/delay.h>
  34#include <linux/dma-mapping.h>
  35#include <linux/dmapool.h>
 
  36#include <linux/of_address.h>
  37#include <linux/of_irq.h>
  38#include <linux/of_platform.h>
  39
  40#include "dmaengine.h"
  41#include "fsldma.h"
  42
  43#define chan_dbg(chan, fmt, arg...)					\
  44	dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg)
  45#define chan_err(chan, fmt, arg...)					\
  46	dev_err(chan->dev, "%s: " fmt, chan->name, ##arg)
  47
  48static const char msg_ld_oom[] = "No free memory for link descriptor";
  49
  50/*
  51 * Register Helpers
  52 */
  53
  54static void set_sr(struct fsldma_chan *chan, u32 val)
  55{
  56	DMA_OUT(chan, &chan->regs->sr, val, 32);
  57}
  58
  59static u32 get_sr(struct fsldma_chan *chan)
  60{
  61	return DMA_IN(chan, &chan->regs->sr, 32);
 
 
 
 
 
 
 
 
 
 
  62}
  63
  64static void set_cdar(struct fsldma_chan *chan, dma_addr_t addr)
  65{
  66	DMA_OUT(chan, &chan->regs->cdar, addr | FSL_DMA_SNEN, 64);
  67}
  68
  69static dma_addr_t get_cdar(struct fsldma_chan *chan)
  70{
  71	return DMA_IN(chan, &chan->regs->cdar, 64) & ~FSL_DMA_SNEN;
 
 
 
 
 
  72}
  73
  74static u32 get_bcr(struct fsldma_chan *chan)
  75{
  76	return DMA_IN(chan, &chan->regs->bcr, 32);
  77}
  78
  79/*
  80 * Descriptor Helpers
  81 */
  82
  83static void set_desc_cnt(struct fsldma_chan *chan,
  84				struct fsl_dma_ld_hw *hw, u32 count)
  85{
  86	hw->count = CPU_TO_DMA(chan, count, 32);
  87}
  88
  89static void set_desc_src(struct fsldma_chan *chan,
  90			 struct fsl_dma_ld_hw *hw, dma_addr_t src)
  91{
  92	u64 snoop_bits;
  93
  94	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
  95		? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0;
  96	hw->src_addr = CPU_TO_DMA(chan, snoop_bits | src, 64);
  97}
  98
  99static void set_desc_dst(struct fsldma_chan *chan,
 100			 struct fsl_dma_ld_hw *hw, dma_addr_t dst)
 101{
 102	u64 snoop_bits;
 103
 104	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
 105		? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0;
 106	hw->dst_addr = CPU_TO_DMA(chan, snoop_bits | dst, 64);
 107}
 108
 109static void set_desc_next(struct fsldma_chan *chan,
 110			  struct fsl_dma_ld_hw *hw, dma_addr_t next)
 111{
 112	u64 snoop_bits;
 113
 114	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
 115		? FSL_DMA_SNEN : 0;
 116	hw->next_ln_addr = CPU_TO_DMA(chan, snoop_bits | next, 64);
 117}
 118
 119static void set_ld_eol(struct fsldma_chan *chan, struct fsl_desc_sw *desc)
 120{
 121	u64 snoop_bits;
 122
 123	snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
 124		? FSL_DMA_SNEN : 0;
 125
 126	desc->hw.next_ln_addr = CPU_TO_DMA(chan,
 127		DMA_TO_CPU(chan, desc->hw.next_ln_addr, 64) | FSL_DMA_EOL
 128			| snoop_bits, 64);
 129}
 130
 131/*
 132 * DMA Engine Hardware Control Helpers
 133 */
 134
 135static void dma_init(struct fsldma_chan *chan)
 136{
 137	/* Reset the channel */
 138	DMA_OUT(chan, &chan->regs->mr, 0, 32);
 139
 140	switch (chan->feature & FSL_DMA_IP_MASK) {
 141	case FSL_DMA_IP_85XX:
 142		/* Set the channel to below modes:
 143		 * EIE - Error interrupt enable
 144		 * EOLNIE - End of links interrupt enable
 145		 * BWC - Bandwidth sharing among channels
 146		 */
 147		DMA_OUT(chan, &chan->regs->mr, FSL_DMA_MR_BWC
 148				| FSL_DMA_MR_EIE | FSL_DMA_MR_EOLNIE, 32);
 149		break;
 150	case FSL_DMA_IP_83XX:
 151		/* Set the channel to below modes:
 152		 * EOTIE - End-of-transfer interrupt enable
 153		 * PRC_RM - PCI read multiple
 154		 */
 155		DMA_OUT(chan, &chan->regs->mr, FSL_DMA_MR_EOTIE
 156				| FSL_DMA_MR_PRC_RM, 32);
 157		break;
 158	}
 159}
 160
 161static int dma_is_idle(struct fsldma_chan *chan)
 162{
 163	u32 sr = get_sr(chan);
 164	return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH);
 165}
 166
 167/*
 168 * Start the DMA controller
 169 *
 170 * Preconditions:
 171 * - the CDAR register must point to the start descriptor
 172 * - the MRn[CS] bit must be cleared
 173 */
 174static void dma_start(struct fsldma_chan *chan)
 175{
 176	u32 mode;
 177
 178	mode = DMA_IN(chan, &chan->regs->mr, 32);
 179
 180	if (chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
 181		DMA_OUT(chan, &chan->regs->bcr, 0, 32);
 182		mode |= FSL_DMA_MR_EMP_EN;
 183	} else {
 184		mode &= ~FSL_DMA_MR_EMP_EN;
 185	}
 186
 187	if (chan->feature & FSL_DMA_CHAN_START_EXT) {
 188		mode |= FSL_DMA_MR_EMS_EN;
 189	} else {
 190		mode &= ~FSL_DMA_MR_EMS_EN;
 191		mode |= FSL_DMA_MR_CS;
 192	}
 193
 194	DMA_OUT(chan, &chan->regs->mr, mode, 32);
 195}
 196
 197static void dma_halt(struct fsldma_chan *chan)
 198{
 199	u32 mode;
 200	int i;
 201
 202	/* read the mode register */
 203	mode = DMA_IN(chan, &chan->regs->mr, 32);
 204
 205	/*
 206	 * The 85xx controller supports channel abort, which will stop
 207	 * the current transfer. On 83xx, this bit is the transfer error
 208	 * mask bit, which should not be changed.
 209	 */
 210	if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) {
 211		mode |= FSL_DMA_MR_CA;
 212		DMA_OUT(chan, &chan->regs->mr, mode, 32);
 213
 214		mode &= ~FSL_DMA_MR_CA;
 215	}
 216
 217	/* stop the DMA controller */
 218	mode &= ~(FSL_DMA_MR_CS | FSL_DMA_MR_EMS_EN);
 219	DMA_OUT(chan, &chan->regs->mr, mode, 32);
 220
 221	/* wait for the DMA controller to become idle */
 222	for (i = 0; i < 100; i++) {
 223		if (dma_is_idle(chan))
 224			return;
 225
 226		udelay(10);
 227	}
 228
 229	if (!dma_is_idle(chan))
 230		chan_err(chan, "DMA halt timeout!\n");
 231}
 232
 233/**
 234 * fsl_chan_set_src_loop_size - Set source address hold transfer size
 235 * @chan : Freescale DMA channel
 236 * @size     : Address loop size, 0 for disable loop
 237 *
 238 * The set source address hold transfer size. The source
 239 * address hold or loop transfer size is when the DMA transfer
 240 * data from source address (SA), if the loop size is 4, the DMA will
 241 * read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA,
 242 * SA + 1 ... and so on.
 243 */
 244static void fsl_chan_set_src_loop_size(struct fsldma_chan *chan, int size)
 245{
 246	u32 mode;
 247
 248	mode = DMA_IN(chan, &chan->regs->mr, 32);
 249
 250	switch (size) {
 251	case 0:
 252		mode &= ~FSL_DMA_MR_SAHE;
 253		break;
 254	case 1:
 255	case 2:
 256	case 4:
 257	case 8:
 
 258		mode |= FSL_DMA_MR_SAHE | (__ilog2(size) << 14);
 259		break;
 260	}
 261
 262	DMA_OUT(chan, &chan->regs->mr, mode, 32);
 263}
 264
 265/**
 266 * fsl_chan_set_dst_loop_size - Set destination address hold transfer size
 267 * @chan : Freescale DMA channel
 268 * @size     : Address loop size, 0 for disable loop
 269 *
 270 * The set destination address hold transfer size. The destination
 271 * address hold or loop transfer size is when the DMA transfer
 272 * data to destination address (TA), if the loop size is 4, the DMA will
 273 * write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA,
 274 * TA + 1 ... and so on.
 275 */
 276static void fsl_chan_set_dst_loop_size(struct fsldma_chan *chan, int size)
 277{
 278	u32 mode;
 279
 280	mode = DMA_IN(chan, &chan->regs->mr, 32);
 281
 282	switch (size) {
 283	case 0:
 284		mode &= ~FSL_DMA_MR_DAHE;
 285		break;
 286	case 1:
 287	case 2:
 288	case 4:
 289	case 8:
 
 290		mode |= FSL_DMA_MR_DAHE | (__ilog2(size) << 16);
 291		break;
 292	}
 293
 294	DMA_OUT(chan, &chan->regs->mr, mode, 32);
 295}
 296
 297/**
 298 * fsl_chan_set_request_count - Set DMA Request Count for external control
 299 * @chan : Freescale DMA channel
 300 * @size     : Number of bytes to transfer in a single request
 301 *
 302 * The Freescale DMA channel can be controlled by the external signal DREQ#.
 303 * The DMA request count is how many bytes are allowed to transfer before
 304 * pausing the channel, after which a new assertion of DREQ# resumes channel
 305 * operation.
 306 *
 307 * A size of 0 disables external pause control. The maximum size is 1024.
 308 */
 309static void fsl_chan_set_request_count(struct fsldma_chan *chan, int size)
 310{
 311	u32 mode;
 312
 313	BUG_ON(size > 1024);
 314
 315	mode = DMA_IN(chan, &chan->regs->mr, 32);
 316	mode |= (__ilog2(size) << 24) & 0x0f000000;
 
 317
 318	DMA_OUT(chan, &chan->regs->mr, mode, 32);
 319}
 320
 321/**
 322 * fsl_chan_toggle_ext_pause - Toggle channel external pause status
 323 * @chan : Freescale DMA channel
 324 * @enable   : 0 is disabled, 1 is enabled.
 325 *
 326 * The Freescale DMA channel can be controlled by the external signal DREQ#.
 327 * The DMA Request Count feature should be used in addition to this feature
 328 * to set the number of bytes to transfer before pausing the channel.
 329 */
 330static void fsl_chan_toggle_ext_pause(struct fsldma_chan *chan, int enable)
 331{
 332	if (enable)
 333		chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
 334	else
 335		chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
 336}
 337
 338/**
 339 * fsl_chan_toggle_ext_start - Toggle channel external start status
 340 * @chan : Freescale DMA channel
 341 * @enable   : 0 is disabled, 1 is enabled.
 342 *
 343 * If enable the external start, the channel can be started by an
 344 * external DMA start pin. So the dma_start() does not start the
 345 * transfer immediately. The DMA channel will wait for the
 346 * control pin asserted.
 347 */
 348static void fsl_chan_toggle_ext_start(struct fsldma_chan *chan, int enable)
 349{
 350	if (enable)
 351		chan->feature |= FSL_DMA_CHAN_START_EXT;
 352	else
 353		chan->feature &= ~FSL_DMA_CHAN_START_EXT;
 354}
 355
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 356static void append_ld_queue(struct fsldma_chan *chan, struct fsl_desc_sw *desc)
 357{
 358	struct fsl_desc_sw *tail = to_fsl_desc(chan->ld_pending.prev);
 359
 360	if (list_empty(&chan->ld_pending))
 361		goto out_splice;
 362
 363	/*
 364	 * Add the hardware descriptor to the chain of hardware descriptors
 365	 * that already exists in memory.
 366	 *
 367	 * This will un-set the EOL bit of the existing transaction, and the
 368	 * last link in this transaction will become the EOL descriptor.
 369	 */
 370	set_desc_next(chan, &tail->hw, desc->async_tx.phys);
 371
 372	/*
 373	 * Add the software descriptor and all children to the list
 374	 * of pending transactions
 375	 */
 376out_splice:
 377	list_splice_tail_init(&desc->tx_list, &chan->ld_pending);
 378}
 379
 380static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 381{
 382	struct fsldma_chan *chan = to_fsl_chan(tx->chan);
 383	struct fsl_desc_sw *desc = tx_to_fsl_desc(tx);
 384	struct fsl_desc_sw *child;
 385	unsigned long flags;
 386	dma_cookie_t cookie = -EINVAL;
 387
 388	spin_lock_irqsave(&chan->desc_lock, flags);
 
 
 
 
 
 
 
 
 389
 390	/*
 391	 * assign cookies to all of the software descriptors
 392	 * that make up this transaction
 393	 */
 394	list_for_each_entry(child, &desc->tx_list, node) {
 395		cookie = dma_cookie_assign(&child->async_tx);
 396	}
 397
 398	/* put this transaction onto the tail of the pending queue */
 399	append_ld_queue(chan, desc);
 400
 401	spin_unlock_irqrestore(&chan->desc_lock, flags);
 402
 403	return cookie;
 404}
 405
 406/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 407 * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool.
 408 * @chan : Freescale DMA channel
 409 *
 410 * Return - The descriptor allocated. NULL for failed.
 411 */
 412static struct fsl_desc_sw *fsl_dma_alloc_descriptor(struct fsldma_chan *chan)
 413{
 414	struct fsl_desc_sw *desc;
 415	dma_addr_t pdesc;
 416
 417	desc = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &pdesc);
 418	if (!desc) {
 419		chan_dbg(chan, "out of memory for link descriptor\n");
 420		return NULL;
 421	}
 422
 423	memset(desc, 0, sizeof(*desc));
 424	INIT_LIST_HEAD(&desc->tx_list);
 425	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
 426	desc->async_tx.tx_submit = fsl_dma_tx_submit;
 427	desc->async_tx.phys = pdesc;
 428
 429#ifdef FSL_DMA_LD_DEBUG
 430	chan_dbg(chan, "LD %p allocated\n", desc);
 431#endif
 432
 433	return desc;
 434}
 435
 436/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 437 * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel.
 438 * @chan : Freescale DMA channel
 439 *
 440 * This function will create a dma pool for descriptor allocation.
 441 *
 442 * Return - The number of descriptors allocated.
 443 */
 444static int fsl_dma_alloc_chan_resources(struct dma_chan *dchan)
 445{
 446	struct fsldma_chan *chan = to_fsl_chan(dchan);
 447
 448	/* Has this channel already been allocated? */
 449	if (chan->desc_pool)
 450		return 1;
 451
 452	/*
 453	 * We need the descriptor to be aligned to 32bytes
 454	 * for meeting FSL DMA specification requirement.
 455	 */
 456	chan->desc_pool = dma_pool_create(chan->name, chan->dev,
 457					  sizeof(struct fsl_desc_sw),
 458					  __alignof__(struct fsl_desc_sw), 0);
 459	if (!chan->desc_pool) {
 460		chan_err(chan, "unable to allocate descriptor pool\n");
 461		return -ENOMEM;
 462	}
 463
 464	/* there is at least one descriptor free to be allocated */
 465	return 1;
 466}
 467
 468/**
 469 * fsldma_free_desc_list - Free all descriptors in a queue
 470 * @chan: Freescae DMA channel
 471 * @list: the list to free
 472 *
 473 * LOCKING: must hold chan->desc_lock
 474 */
 475static void fsldma_free_desc_list(struct fsldma_chan *chan,
 476				  struct list_head *list)
 477{
 478	struct fsl_desc_sw *desc, *_desc;
 479
 480	list_for_each_entry_safe(desc, _desc, list, node) {
 481		list_del(&desc->node);
 482#ifdef FSL_DMA_LD_DEBUG
 483		chan_dbg(chan, "LD %p free\n", desc);
 484#endif
 485		dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
 486	}
 487}
 488
 489static void fsldma_free_desc_list_reverse(struct fsldma_chan *chan,
 490					  struct list_head *list)
 491{
 492	struct fsl_desc_sw *desc, *_desc;
 493
 494	list_for_each_entry_safe_reverse(desc, _desc, list, node) {
 495		list_del(&desc->node);
 496#ifdef FSL_DMA_LD_DEBUG
 497		chan_dbg(chan, "LD %p free\n", desc);
 498#endif
 499		dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
 500	}
 501}
 502
 503/**
 504 * fsl_dma_free_chan_resources - Free all resources of the channel.
 505 * @chan : Freescale DMA channel
 506 */
 507static void fsl_dma_free_chan_resources(struct dma_chan *dchan)
 508{
 509	struct fsldma_chan *chan = to_fsl_chan(dchan);
 510	unsigned long flags;
 511
 512	chan_dbg(chan, "free all channel resources\n");
 513	spin_lock_irqsave(&chan->desc_lock, flags);
 
 514	fsldma_free_desc_list(chan, &chan->ld_pending);
 515	fsldma_free_desc_list(chan, &chan->ld_running);
 516	spin_unlock_irqrestore(&chan->desc_lock, flags);
 
 517
 518	dma_pool_destroy(chan->desc_pool);
 519	chan->desc_pool = NULL;
 520}
 521
 522static struct dma_async_tx_descriptor *
 523fsl_dma_prep_interrupt(struct dma_chan *dchan, unsigned long flags)
 524{
 525	struct fsldma_chan *chan;
 526	struct fsl_desc_sw *new;
 527
 528	if (!dchan)
 529		return NULL;
 530
 531	chan = to_fsl_chan(dchan);
 532
 533	new = fsl_dma_alloc_descriptor(chan);
 534	if (!new) {
 535		chan_err(chan, "%s\n", msg_ld_oom);
 536		return NULL;
 537	}
 538
 539	new->async_tx.cookie = -EBUSY;
 540	new->async_tx.flags = flags;
 541
 542	/* Insert the link descriptor to the LD ring */
 543	list_add_tail(&new->node, &new->tx_list);
 544
 545	/* Set End-of-link to the last link descriptor of new list */
 546	set_ld_eol(chan, new);
 547
 548	return &new->async_tx;
 549}
 550
 551static struct dma_async_tx_descriptor *
 552fsl_dma_prep_memcpy(struct dma_chan *dchan,
 553	dma_addr_t dma_dst, dma_addr_t dma_src,
 554	size_t len, unsigned long flags)
 555{
 556	struct fsldma_chan *chan;
 557	struct fsl_desc_sw *first = NULL, *prev = NULL, *new;
 558	size_t copy;
 559
 560	if (!dchan)
 561		return NULL;
 562
 563	if (!len)
 564		return NULL;
 565
 566	chan = to_fsl_chan(dchan);
 567
 568	do {
 569
 570		/* Allocate the link descriptor from DMA pool */
 571		new = fsl_dma_alloc_descriptor(chan);
 572		if (!new) {
 573			chan_err(chan, "%s\n", msg_ld_oom);
 574			goto fail;
 575		}
 576
 577		copy = min(len, (size_t)FSL_DMA_BCR_MAX_CNT);
 578
 579		set_desc_cnt(chan, &new->hw, copy);
 580		set_desc_src(chan, &new->hw, dma_src);
 581		set_desc_dst(chan, &new->hw, dma_dst);
 582
 583		if (!first)
 584			first = new;
 585		else
 586			set_desc_next(chan, &prev->hw, new->async_tx.phys);
 587
 588		new->async_tx.cookie = 0;
 589		async_tx_ack(&new->async_tx);
 590
 591		prev = new;
 592		len -= copy;
 593		dma_src += copy;
 594		dma_dst += copy;
 595
 596		/* Insert the link descriptor to the LD ring */
 597		list_add_tail(&new->node, &first->tx_list);
 598	} while (len);
 599
 600	new->async_tx.flags = flags; /* client is in control of this ack */
 601	new->async_tx.cookie = -EBUSY;
 602
 603	/* Set End-of-link to the last link descriptor of new list */
 604	set_ld_eol(chan, new);
 605
 606	return &first->async_tx;
 607
 608fail:
 609	if (!first)
 610		return NULL;
 611
 612	fsldma_free_desc_list_reverse(chan, &first->tx_list);
 613	return NULL;
 614}
 615
 616static struct dma_async_tx_descriptor *fsl_dma_prep_sg(struct dma_chan *dchan,
 617	struct scatterlist *dst_sg, unsigned int dst_nents,
 618	struct scatterlist *src_sg, unsigned int src_nents,
 619	unsigned long flags)
 620{
 621	struct fsl_desc_sw *first = NULL, *prev = NULL, *new = NULL;
 622	struct fsldma_chan *chan = to_fsl_chan(dchan);
 623	size_t dst_avail, src_avail;
 624	dma_addr_t dst, src;
 625	size_t len;
 626
 627	/* basic sanity checks */
 628	if (dst_nents == 0 || src_nents == 0)
 629		return NULL;
 630
 631	if (dst_sg == NULL || src_sg == NULL)
 632		return NULL;
 633
 634	/*
 635	 * TODO: should we check that both scatterlists have the same
 636	 * TODO: number of bytes in total? Is that really an error?
 637	 */
 638
 639	/* get prepared for the loop */
 640	dst_avail = sg_dma_len(dst_sg);
 641	src_avail = sg_dma_len(src_sg);
 642
 643	/* run until we are out of scatterlist entries */
 644	while (true) {
 645
 646		/* create the largest transaction possible */
 647		len = min_t(size_t, src_avail, dst_avail);
 648		len = min_t(size_t, len, FSL_DMA_BCR_MAX_CNT);
 649		if (len == 0)
 650			goto fetch;
 651
 652		dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail;
 653		src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail;
 
 
 
 654
 655		/* allocate and populate the descriptor */
 656		new = fsl_dma_alloc_descriptor(chan);
 657		if (!new) {
 658			chan_err(chan, "%s\n", msg_ld_oom);
 659			goto fail;
 660		}
 661
 662		set_desc_cnt(chan, &new->hw, len);
 663		set_desc_src(chan, &new->hw, src);
 664		set_desc_dst(chan, &new->hw, dst);
 665
 666		if (!first)
 667			first = new;
 668		else
 669			set_desc_next(chan, &prev->hw, new->async_tx.phys);
 670
 671		new->async_tx.cookie = 0;
 672		async_tx_ack(&new->async_tx);
 673		prev = new;
 674
 675		/* Insert the link descriptor to the LD ring */
 676		list_add_tail(&new->node, &first->tx_list);
 677
 678		/* update metadata */
 679		dst_avail -= len;
 680		src_avail -= len;
 681
 682fetch:
 683		/* fetch the next dst scatterlist entry */
 684		if (dst_avail == 0) {
 685
 686			/* no more entries: we're done */
 687			if (dst_nents == 0)
 688				break;
 689
 690			/* fetch the next entry: if there are no more: done */
 691			dst_sg = sg_next(dst_sg);
 692			if (dst_sg == NULL)
 693				break;
 694
 695			dst_nents--;
 696			dst_avail = sg_dma_len(dst_sg);
 697		}
 698
 699		/* fetch the next src scatterlist entry */
 700		if (src_avail == 0) {
 701
 702			/* no more entries: we're done */
 703			if (src_nents == 0)
 704				break;
 705
 706			/* fetch the next entry: if there are no more: done */
 707			src_sg = sg_next(src_sg);
 708			if (src_sg == NULL)
 709				break;
 710
 711			src_nents--;
 712			src_avail = sg_dma_len(src_sg);
 713		}
 714	}
 715
 716	new->async_tx.flags = flags; /* client is in control of this ack */
 717	new->async_tx.cookie = -EBUSY;
 718
 719	/* Set End-of-link to the last link descriptor of new list */
 720	set_ld_eol(chan, new);
 721
 722	return &first->async_tx;
 723
 724fail:
 725	if (!first)
 726		return NULL;
 727
 728	fsldma_free_desc_list_reverse(chan, &first->tx_list);
 729	return NULL;
 730}
 731
 732/**
 733 * fsl_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
 734 * @chan: DMA channel
 735 * @sgl: scatterlist to transfer to/from
 736 * @sg_len: number of entries in @scatterlist
 737 * @direction: DMA direction
 738 * @flags: DMAEngine flags
 739 * @context: transaction context (ignored)
 740 *
 741 * Prepare a set of descriptors for a DMA_SLAVE transaction. Following the
 742 * DMA_SLAVE API, this gets the device-specific information from the
 743 * chan->private variable.
 744 */
 745static struct dma_async_tx_descriptor *fsl_dma_prep_slave_sg(
 746	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
 747	enum dma_transfer_direction direction, unsigned long flags,
 748	void *context)
 749{
 750	/*
 751	 * This operation is not supported on the Freescale DMA controller
 752	 *
 753	 * However, we need to provide the function pointer to allow the
 754	 * device_control() method to work.
 755	 */
 756	return NULL;
 757}
 758
 759static int fsl_dma_device_control(struct dma_chan *dchan,
 760				  enum dma_ctrl_cmd cmd, unsigned long arg)
 761{
 762	struct dma_slave_config *config;
 763	struct fsldma_chan *chan;
 764	unsigned long flags;
 765	int size;
 766
 767	if (!dchan)
 768		return -EINVAL;
 769
 770	chan = to_fsl_chan(dchan);
 771
 772	switch (cmd) {
 773	case DMA_TERMINATE_ALL:
 774		spin_lock_irqsave(&chan->desc_lock, flags);
 775
 776		/* Halt the DMA engine */
 777		dma_halt(chan);
 778
 779		/* Remove and free all of the descriptors in the LD queue */
 780		fsldma_free_desc_list(chan, &chan->ld_pending);
 781		fsldma_free_desc_list(chan, &chan->ld_running);
 782		chan->idle = true;
 783
 784		spin_unlock_irqrestore(&chan->desc_lock, flags);
 785		return 0;
 786
 787	case DMA_SLAVE_CONFIG:
 788		config = (struct dma_slave_config *)arg;
 789
 790		/* make sure the channel supports setting burst size */
 791		if (!chan->set_request_count)
 792			return -ENXIO;
 793
 794		/* we set the controller burst size depending on direction */
 795		if (config->direction == DMA_MEM_TO_DEV)
 796			size = config->dst_addr_width * config->dst_maxburst;
 797		else
 798			size = config->src_addr_width * config->src_maxburst;
 799
 800		chan->set_request_count(chan, size);
 801		return 0;
 802
 803	case FSLDMA_EXTERNAL_START:
 804
 805		/* make sure the channel supports external start */
 806		if (!chan->toggle_ext_start)
 807			return -ENXIO;
 808
 809		chan->toggle_ext_start(chan, arg);
 810		return 0;
 811
 812	default:
 813		return -ENXIO;
 814	}
 815
 
 816	return 0;
 817}
 818
 819/**
 820 * fsldma_cleanup_descriptor - cleanup and free a single link descriptor
 821 * @chan: Freescale DMA channel
 822 * @desc: descriptor to cleanup and free
 823 *
 824 * This function is used on a descriptor which has been executed by the DMA
 825 * controller. It will run any callbacks, submit any dependencies, and then
 826 * free the descriptor.
 827 */
 828static void fsldma_cleanup_descriptor(struct fsldma_chan *chan,
 829				      struct fsl_desc_sw *desc)
 830{
 831	struct dma_async_tx_descriptor *txd = &desc->async_tx;
 832
 833	/* Run the link descriptor callback function */
 834	if (txd->callback) {
 835#ifdef FSL_DMA_LD_DEBUG
 836		chan_dbg(chan, "LD %p callback\n", desc);
 837#endif
 838		txd->callback(txd->callback_param);
 839	}
 840
 841	/* Run any dependencies */
 842	dma_run_dependencies(txd);
 843
 844	dma_descriptor_unmap(txd);
 845#ifdef FSL_DMA_LD_DEBUG
 846	chan_dbg(chan, "LD %p free\n", desc);
 847#endif
 848	dma_pool_free(chan->desc_pool, desc, txd->phys);
 849}
 850
 851/**
 852 * fsl_chan_xfer_ld_queue - transfer any pending transactions
 853 * @chan : Freescale DMA channel
 854 *
 855 * HARDWARE STATE: idle
 856 * LOCKING: must hold chan->desc_lock
 857 */
 858static void fsl_chan_xfer_ld_queue(struct fsldma_chan *chan)
 859{
 860	struct fsl_desc_sw *desc;
 861
 862	/*
 863	 * If the list of pending descriptors is empty, then we
 864	 * don't need to do any work at all
 865	 */
 866	if (list_empty(&chan->ld_pending)) {
 867		chan_dbg(chan, "no pending LDs\n");
 868		return;
 869	}
 870
 871	/*
 872	 * The DMA controller is not idle, which means that the interrupt
 873	 * handler will start any queued transactions when it runs after
 874	 * this transaction finishes
 875	 */
 876	if (!chan->idle) {
 877		chan_dbg(chan, "DMA controller still busy\n");
 878		return;
 879	}
 880
 881	/*
 882	 * If there are some link descriptors which have not been
 883	 * transferred, we need to start the controller
 884	 */
 885
 886	/*
 887	 * Move all elements from the queue of pending transactions
 888	 * onto the list of running transactions
 889	 */
 890	chan_dbg(chan, "idle, starting controller\n");
 891	desc = list_first_entry(&chan->ld_pending, struct fsl_desc_sw, node);
 892	list_splice_tail_init(&chan->ld_pending, &chan->ld_running);
 893
 894	/*
 895	 * The 85xx DMA controller doesn't clear the channel start bit
 896	 * automatically at the end of a transfer. Therefore we must clear
 897	 * it in software before starting the transfer.
 898	 */
 899	if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) {
 900		u32 mode;
 901
 902		mode = DMA_IN(chan, &chan->regs->mr, 32);
 903		mode &= ~FSL_DMA_MR_CS;
 904		DMA_OUT(chan, &chan->regs->mr, mode, 32);
 905	}
 906
 907	/*
 908	 * Program the descriptor's address into the DMA controller,
 909	 * then start the DMA transaction
 910	 */
 911	set_cdar(chan, desc->async_tx.phys);
 912	get_cdar(chan);
 913
 914	dma_start(chan);
 915	chan->idle = false;
 916}
 917
 918/**
 919 * fsl_dma_memcpy_issue_pending - Issue the DMA start command
 920 * @chan : Freescale DMA channel
 921 */
 922static void fsl_dma_memcpy_issue_pending(struct dma_chan *dchan)
 923{
 924	struct fsldma_chan *chan = to_fsl_chan(dchan);
 925	unsigned long flags;
 926
 927	spin_lock_irqsave(&chan->desc_lock, flags);
 928	fsl_chan_xfer_ld_queue(chan);
 929	spin_unlock_irqrestore(&chan->desc_lock, flags);
 930}
 931
 932/**
 933 * fsl_tx_status - Determine the DMA status
 934 * @chan : Freescale DMA channel
 935 */
 936static enum dma_status fsl_tx_status(struct dma_chan *dchan,
 937					dma_cookie_t cookie,
 938					struct dma_tx_state *txstate)
 939{
 
 
 
 
 
 
 
 
 
 
 
 940	return dma_cookie_status(dchan, cookie, txstate);
 941}
 942
 943/*----------------------------------------------------------------------------*/
 944/* Interrupt Handling                                                         */
 945/*----------------------------------------------------------------------------*/
 946
 947static irqreturn_t fsldma_chan_irq(int irq, void *data)
 948{
 949	struct fsldma_chan *chan = data;
 950	u32 stat;
 951
 952	/* save and clear the status register */
 953	stat = get_sr(chan);
 954	set_sr(chan, stat);
 955	chan_dbg(chan, "irq: stat = 0x%x\n", stat);
 956
 957	/* check that this was really our device */
 958	stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH);
 959	if (!stat)
 960		return IRQ_NONE;
 961
 962	if (stat & FSL_DMA_SR_TE)
 963		chan_err(chan, "Transfer Error!\n");
 964
 965	/*
 966	 * Programming Error
 967	 * The DMA_INTERRUPT async_tx is a NULL transfer, which will
 968	 * trigger a PE interrupt.
 969	 */
 970	if (stat & FSL_DMA_SR_PE) {
 971		chan_dbg(chan, "irq: Programming Error INT\n");
 972		stat &= ~FSL_DMA_SR_PE;
 973		if (get_bcr(chan) != 0)
 974			chan_err(chan, "Programming Error!\n");
 975	}
 976
 977	/*
 978	 * For MPC8349, EOCDI event need to update cookie
 979	 * and start the next transfer if it exist.
 980	 */
 981	if (stat & FSL_DMA_SR_EOCDI) {
 982		chan_dbg(chan, "irq: End-of-Chain link INT\n");
 983		stat &= ~FSL_DMA_SR_EOCDI;
 984	}
 985
 986	/*
 987	 * If it current transfer is the end-of-transfer,
 988	 * we should clear the Channel Start bit for
 989	 * prepare next transfer.
 990	 */
 991	if (stat & FSL_DMA_SR_EOLNI) {
 992		chan_dbg(chan, "irq: End-of-link INT\n");
 993		stat &= ~FSL_DMA_SR_EOLNI;
 994	}
 995
 996	/* check that the DMA controller is really idle */
 997	if (!dma_is_idle(chan))
 998		chan_err(chan, "irq: controller not idle!\n");
 999
1000	/* check that we handled all of the bits */
1001	if (stat)
1002		chan_err(chan, "irq: unhandled sr 0x%08x\n", stat);
1003
1004	/*
1005	 * Schedule the tasklet to handle all cleanup of the current
1006	 * transaction. It will start a new transaction if there is
1007	 * one pending.
1008	 */
1009	tasklet_schedule(&chan->tasklet);
1010	chan_dbg(chan, "irq: Exit\n");
1011	return IRQ_HANDLED;
1012}
1013
1014static void dma_do_tasklet(unsigned long data)
1015{
1016	struct fsldma_chan *chan = (struct fsldma_chan *)data;
1017	struct fsl_desc_sw *desc, *_desc;
1018	LIST_HEAD(ld_cleanup);
1019	unsigned long flags;
1020
1021	chan_dbg(chan, "tasklet entry\n");
1022
1023	spin_lock_irqsave(&chan->desc_lock, flags);
1024
1025	/* update the cookie if we have some descriptors to cleanup */
1026	if (!list_empty(&chan->ld_running)) {
1027		dma_cookie_t cookie;
1028
1029		desc = to_fsl_desc(chan->ld_running.prev);
1030		cookie = desc->async_tx.cookie;
1031		dma_cookie_complete(&desc->async_tx);
1032
1033		chan_dbg(chan, "completed_cookie=%d\n", cookie);
1034	}
1035
1036	/*
1037	 * move the descriptors to a temporary list so we can drop the lock
1038	 * during the entire cleanup operation
1039	 */
1040	list_splice_tail_init(&chan->ld_running, &ld_cleanup);
1041
1042	/* the hardware is now idle and ready for more */
1043	chan->idle = true;
1044
1045	/*
1046	 * Start any pending transactions automatically
1047	 *
1048	 * In the ideal case, we keep the DMA controller busy while we go
1049	 * ahead and free the descriptors below.
1050	 */
1051	fsl_chan_xfer_ld_queue(chan);
1052	spin_unlock_irqrestore(&chan->desc_lock, flags);
1053
1054	/* Run the callback for each descriptor, in order */
1055	list_for_each_entry_safe(desc, _desc, &ld_cleanup, node) {
1056
1057		/* Remove from the list of transactions */
1058		list_del(&desc->node);
1059
1060		/* Run all cleanup for this descriptor */
1061		fsldma_cleanup_descriptor(chan, desc);
1062	}
1063
1064	chan_dbg(chan, "tasklet exit\n");
1065}
1066
1067static irqreturn_t fsldma_ctrl_irq(int irq, void *data)
1068{
1069	struct fsldma_device *fdev = data;
1070	struct fsldma_chan *chan;
1071	unsigned int handled = 0;
1072	u32 gsr, mask;
1073	int i;
1074
1075	gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs)
1076						   : in_le32(fdev->regs);
1077	mask = 0xff000000;
1078	dev_dbg(fdev->dev, "IRQ: gsr 0x%.8x\n", gsr);
1079
1080	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1081		chan = fdev->chan[i];
1082		if (!chan)
1083			continue;
1084
1085		if (gsr & mask) {
1086			dev_dbg(fdev->dev, "IRQ: chan %d\n", chan->id);
1087			fsldma_chan_irq(irq, chan);
1088			handled++;
1089		}
1090
1091		gsr &= ~mask;
1092		mask >>= 8;
1093	}
1094
1095	return IRQ_RETVAL(handled);
1096}
1097
1098static void fsldma_free_irqs(struct fsldma_device *fdev)
1099{
1100	struct fsldma_chan *chan;
1101	int i;
1102
1103	if (fdev->irq != NO_IRQ) {
1104		dev_dbg(fdev->dev, "free per-controller IRQ\n");
1105		free_irq(fdev->irq, fdev);
1106		return;
1107	}
1108
1109	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1110		chan = fdev->chan[i];
1111		if (chan && chan->irq != NO_IRQ) {
1112			chan_dbg(chan, "free per-channel IRQ\n");
1113			free_irq(chan->irq, chan);
1114		}
1115	}
1116}
1117
1118static int fsldma_request_irqs(struct fsldma_device *fdev)
1119{
1120	struct fsldma_chan *chan;
1121	int ret;
1122	int i;
1123
1124	/* if we have a per-controller IRQ, use that */
1125	if (fdev->irq != NO_IRQ) {
1126		dev_dbg(fdev->dev, "request per-controller IRQ\n");
1127		ret = request_irq(fdev->irq, fsldma_ctrl_irq, IRQF_SHARED,
1128				  "fsldma-controller", fdev);
1129		return ret;
1130	}
1131
1132	/* no per-controller IRQ, use the per-channel IRQs */
1133	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1134		chan = fdev->chan[i];
1135		if (!chan)
1136			continue;
1137
1138		if (chan->irq == NO_IRQ) {
1139			chan_err(chan, "interrupts property missing in device tree\n");
1140			ret = -ENODEV;
1141			goto out_unwind;
1142		}
1143
1144		chan_dbg(chan, "request per-channel IRQ\n");
1145		ret = request_irq(chan->irq, fsldma_chan_irq, IRQF_SHARED,
1146				  "fsldma-chan", chan);
1147		if (ret) {
1148			chan_err(chan, "unable to request per-channel IRQ\n");
1149			goto out_unwind;
1150		}
1151	}
1152
1153	return 0;
1154
1155out_unwind:
1156	for (/* none */; i >= 0; i--) {
1157		chan = fdev->chan[i];
1158		if (!chan)
1159			continue;
1160
1161		if (chan->irq == NO_IRQ)
1162			continue;
1163
1164		free_irq(chan->irq, chan);
1165	}
1166
1167	return ret;
1168}
1169
1170/*----------------------------------------------------------------------------*/
1171/* OpenFirmware Subsystem                                                     */
1172/*----------------------------------------------------------------------------*/
1173
1174static int fsl_dma_chan_probe(struct fsldma_device *fdev,
1175	struct device_node *node, u32 feature, const char *compatible)
1176{
1177	struct fsldma_chan *chan;
1178	struct resource res;
1179	int err;
1180
1181	/* alloc channel */
1182	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1183	if (!chan) {
1184		dev_err(fdev->dev, "no free memory for DMA channels!\n");
1185		err = -ENOMEM;
1186		goto out_return;
1187	}
1188
1189	/* ioremap registers for use */
1190	chan->regs = of_iomap(node, 0);
1191	if (!chan->regs) {
1192		dev_err(fdev->dev, "unable to ioremap registers\n");
1193		err = -ENOMEM;
1194		goto out_free_chan;
1195	}
1196
1197	err = of_address_to_resource(node, 0, &res);
1198	if (err) {
1199		dev_err(fdev->dev, "unable to find 'reg' property\n");
1200		goto out_iounmap_regs;
1201	}
1202
1203	chan->feature = feature;
1204	if (!fdev->feature)
1205		fdev->feature = chan->feature;
1206
1207	/*
1208	 * If the DMA device's feature is different than the feature
1209	 * of its channels, report the bug
1210	 */
1211	WARN_ON(fdev->feature != chan->feature);
1212
1213	chan->dev = fdev->dev;
1214	chan->id = (res.start & 0xfff) < 0x300 ?
1215		   ((res.start - 0x100) & 0xfff) >> 7 :
1216		   ((res.start - 0x200) & 0xfff) >> 7;
1217	if (chan->id >= FSL_DMA_MAX_CHANS_PER_DEVICE) {
1218		dev_err(fdev->dev, "too many channels for device\n");
1219		err = -EINVAL;
1220		goto out_iounmap_regs;
1221	}
1222
1223	fdev->chan[chan->id] = chan;
1224	tasklet_init(&chan->tasklet, dma_do_tasklet, (unsigned long)chan);
1225	snprintf(chan->name, sizeof(chan->name), "chan%d", chan->id);
1226
1227	/* Initialize the channel */
1228	dma_init(chan);
1229
1230	/* Clear cdar registers */
1231	set_cdar(chan, 0);
1232
1233	switch (chan->feature & FSL_DMA_IP_MASK) {
1234	case FSL_DMA_IP_85XX:
1235		chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
 
1236	case FSL_DMA_IP_83XX:
1237		chan->toggle_ext_start = fsl_chan_toggle_ext_start;
1238		chan->set_src_loop_size = fsl_chan_set_src_loop_size;
1239		chan->set_dst_loop_size = fsl_chan_set_dst_loop_size;
1240		chan->set_request_count = fsl_chan_set_request_count;
1241	}
1242
1243	spin_lock_init(&chan->desc_lock);
1244	INIT_LIST_HEAD(&chan->ld_pending);
1245	INIT_LIST_HEAD(&chan->ld_running);
 
1246	chan->idle = true;
 
 
 
1247
1248	chan->common.device = &fdev->common;
1249	dma_cookie_init(&chan->common);
1250
1251	/* find the IRQ line, if it exists in the device tree */
1252	chan->irq = irq_of_parse_and_map(node, 0);
1253
1254	/* Add the channel to DMA device channel list */
1255	list_add_tail(&chan->common.device_node, &fdev->common.channels);
1256	fdev->common.chancnt++;
1257
1258	dev_info(fdev->dev, "#%d (%s), irq %d\n", chan->id, compatible,
1259		 chan->irq != NO_IRQ ? chan->irq : fdev->irq);
1260
1261	return 0;
1262
1263out_iounmap_regs:
1264	iounmap(chan->regs);
1265out_free_chan:
1266	kfree(chan);
1267out_return:
1268	return err;
1269}
1270
1271static void fsl_dma_chan_remove(struct fsldma_chan *chan)
1272{
1273	irq_dispose_mapping(chan->irq);
1274	list_del(&chan->common.device_node);
1275	iounmap(chan->regs);
1276	kfree(chan);
1277}
1278
1279static int fsldma_of_probe(struct platform_device *op)
1280{
1281	struct fsldma_device *fdev;
1282	struct device_node *child;
 
1283	int err;
1284
1285	fdev = kzalloc(sizeof(*fdev), GFP_KERNEL);
1286	if (!fdev) {
1287		dev_err(&op->dev, "No enough memory for 'priv'\n");
1288		err = -ENOMEM;
1289		goto out_return;
1290	}
1291
1292	fdev->dev = &op->dev;
1293	INIT_LIST_HEAD(&fdev->common.channels);
1294
1295	/* ioremap the registers for use */
1296	fdev->regs = of_iomap(op->dev.of_node, 0);
1297	if (!fdev->regs) {
1298		dev_err(&op->dev, "unable to ioremap registers\n");
1299		err = -ENOMEM;
1300		goto out_free_fdev;
1301	}
1302
1303	/* map the channel IRQ if it exists, but don't hookup the handler yet */
1304	fdev->irq = irq_of_parse_and_map(op->dev.of_node, 0);
1305
1306	dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
1307	dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask);
1308	dma_cap_set(DMA_SG, fdev->common.cap_mask);
1309	dma_cap_set(DMA_SLAVE, fdev->common.cap_mask);
1310	fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources;
1311	fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources;
1312	fdev->common.device_prep_dma_interrupt = fsl_dma_prep_interrupt;
1313	fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
1314	fdev->common.device_prep_dma_sg = fsl_dma_prep_sg;
1315	fdev->common.device_tx_status = fsl_tx_status;
1316	fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
1317	fdev->common.device_prep_slave_sg = fsl_dma_prep_slave_sg;
1318	fdev->common.device_control = fsl_dma_device_control;
1319	fdev->common.dev = &op->dev;
1320
 
 
 
 
 
1321	dma_set_mask(&(op->dev), DMA_BIT_MASK(36));
1322
1323	platform_set_drvdata(op, fdev);
1324
1325	/*
1326	 * We cannot use of_platform_bus_probe() because there is no
1327	 * of_platform_bus_remove(). Instead, we manually instantiate every DMA
1328	 * channel object.
1329	 */
1330	for_each_child_of_node(op->dev.of_node, child) {
1331		if (of_device_is_compatible(child, "fsl,eloplus-dma-channel")) {
1332			fsl_dma_chan_probe(fdev, child,
1333				FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN,
1334				"fsl,eloplus-dma-channel");
1335		}
1336
1337		if (of_device_is_compatible(child, "fsl,elo-dma-channel")) {
1338			fsl_dma_chan_probe(fdev, child,
1339				FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN,
1340				"fsl,elo-dma-channel");
1341		}
1342	}
1343
1344	/*
1345	 * Hookup the IRQ handler(s)
1346	 *
1347	 * If we have a per-controller interrupt, we prefer that to the
1348	 * per-channel interrupts to reduce the number of shared interrupt
1349	 * handlers on the same IRQ line
1350	 */
1351	err = fsldma_request_irqs(fdev);
1352	if (err) {
1353		dev_err(fdev->dev, "unable to request IRQs\n");
1354		goto out_free_fdev;
1355	}
1356
1357	dma_async_device_register(&fdev->common);
1358	return 0;
1359
1360out_free_fdev:
 
 
 
 
1361	irq_dispose_mapping(fdev->irq);
 
 
1362	kfree(fdev);
1363out_return:
1364	return err;
1365}
1366
1367static int fsldma_of_remove(struct platform_device *op)
1368{
1369	struct fsldma_device *fdev;
1370	unsigned int i;
1371
1372	fdev = platform_get_drvdata(op);
1373	dma_async_device_unregister(&fdev->common);
1374
1375	fsldma_free_irqs(fdev);
1376
1377	for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) {
1378		if (fdev->chan[i])
1379			fsl_dma_chan_remove(fdev->chan[i]);
1380	}
 
1381
1382	iounmap(fdev->regs);
1383	kfree(fdev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1384
1385	return 0;
1386}
1387
 
 
 
 
 
 
1388static const struct of_device_id fsldma_of_ids[] = {
1389	{ .compatible = "fsl,elo3-dma", },
1390	{ .compatible = "fsl,eloplus-dma", },
1391	{ .compatible = "fsl,elo-dma", },
1392	{}
1393};
 
1394
1395static struct platform_driver fsldma_of_driver = {
1396	.driver = {
1397		.name = "fsl-elo-dma",
1398		.owner = THIS_MODULE,
1399		.of_match_table = fsldma_of_ids,
 
 
 
1400	},
1401	.probe = fsldma_of_probe,
1402	.remove = fsldma_of_remove,
1403};
1404
1405/*----------------------------------------------------------------------------*/
1406/* Module Init / Exit                                                         */
1407/*----------------------------------------------------------------------------*/
1408
1409static __init int fsldma_init(void)
1410{
1411	pr_info("Freescale Elo series DMA driver\n");
1412	return platform_driver_register(&fsldma_of_driver);
1413}
1414
1415static void __exit fsldma_exit(void)
1416{
1417	platform_driver_unregister(&fsldma_of_driver);
1418}
1419
1420subsys_initcall(fsldma_init);
1421module_exit(fsldma_exit);
1422
1423MODULE_DESCRIPTION("Freescale Elo series DMA driver");
1424MODULE_LICENSE("GPL");