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   1/*
   2 * Renesas SuperH DMA Engine support
   3 *
   4 * base is drivers/dma/flsdma.c
   5 *
   6 * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
   7 * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
   8 * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
   9 *
  10 * This is free software; you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License as published by
  12 * the Free Software Foundation; either version 2 of the License, or
  13 * (at your option) any later version.
  14 *
  15 * - DMA of SuperH does not have Hardware DMA chain mode.
  16 * - MAX DMA size is 16MB.
  17 *
  18 */
  19
  20#include <linux/init.h>
  21#include <linux/module.h>
  22#include <linux/slab.h>
  23#include <linux/interrupt.h>
  24#include <linux/dmaengine.h>
  25#include <linux/delay.h>
  26#include <linux/dma-mapping.h>
  27#include <linux/platform_device.h>
  28#include <linux/pm_runtime.h>
  29#include <linux/sh_dma.h>
  30#include <linux/notifier.h>
  31#include <linux/kdebug.h>
  32#include <linux/spinlock.h>
  33#include <linux/rculist.h>
  34#include "shdma.h"
  35
  36/* DMA descriptor control */
  37enum sh_dmae_desc_status {
  38	DESC_IDLE,
  39	DESC_PREPARED,
  40	DESC_SUBMITTED,
  41	DESC_COMPLETED,	/* completed, have to call callback */
  42	DESC_WAITING,	/* callback called, waiting for ack / re-submit */
  43};
  44
  45#define NR_DESCS_PER_CHANNEL 32
  46/* Default MEMCPY transfer size = 2^2 = 4 bytes */
  47#define LOG2_DEFAULT_XFER_SIZE	2
  48
  49/*
  50 * Used for write-side mutual exclusion for the global device list,
  51 * read-side synchronization by way of RCU, and per-controller data.
  52 */
  53static DEFINE_SPINLOCK(sh_dmae_lock);
  54static LIST_HEAD(sh_dmae_devices);
  55
  56/* A bitmask with bits enough for enum sh_dmae_slave_chan_id */
  57static unsigned long sh_dmae_slave_used[BITS_TO_LONGS(SH_DMA_SLAVE_NUMBER)];
  58
  59static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all);
  60
  61static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
  62{
  63	__raw_writel(data, sh_dc->base + reg / sizeof(u32));
  64}
  65
  66static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
  67{
  68	return __raw_readl(sh_dc->base + reg / sizeof(u32));
  69}
  70
  71static u16 dmaor_read(struct sh_dmae_device *shdev)
  72{
  73	u32 __iomem *addr = shdev->chan_reg + DMAOR / sizeof(u32);
  74
  75	if (shdev->pdata->dmaor_is_32bit)
  76		return __raw_readl(addr);
  77	else
  78		return __raw_readw(addr);
  79}
  80
  81static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
  82{
  83	u32 __iomem *addr = shdev->chan_reg + DMAOR / sizeof(u32);
  84
  85	if (shdev->pdata->dmaor_is_32bit)
  86		__raw_writel(data, addr);
  87	else
  88		__raw_writew(data, addr);
  89}
  90
  91static void chcr_write(struct sh_dmae_chan *sh_dc, u32 data)
  92{
  93	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
  94
  95	__raw_writel(data, sh_dc->base + shdev->chcr_offset / sizeof(u32));
  96}
  97
  98static u32 chcr_read(struct sh_dmae_chan *sh_dc)
  99{
 100	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
 101
 102	return __raw_readl(sh_dc->base + shdev->chcr_offset / sizeof(u32));
 103}
 104
 105/*
 106 * Reset DMA controller
 107 *
 108 * SH7780 has two DMAOR register
 109 */
 110static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
 111{
 112	unsigned short dmaor;
 113	unsigned long flags;
 114
 115	spin_lock_irqsave(&sh_dmae_lock, flags);
 116
 117	dmaor = dmaor_read(shdev);
 118	dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
 119
 120	spin_unlock_irqrestore(&sh_dmae_lock, flags);
 121}
 122
 123static int sh_dmae_rst(struct sh_dmae_device *shdev)
 124{
 125	unsigned short dmaor;
 126	unsigned long flags;
 127
 128	spin_lock_irqsave(&sh_dmae_lock, flags);
 129
 130	dmaor = dmaor_read(shdev) & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME);
 131
 132	dmaor_write(shdev, dmaor | shdev->pdata->dmaor_init);
 133
 134	dmaor = dmaor_read(shdev);
 135
 136	spin_unlock_irqrestore(&sh_dmae_lock, flags);
 137
 138	if (dmaor & (DMAOR_AE | DMAOR_NMIF)) {
 139		dev_warn(shdev->common.dev, "Can't initialize DMAOR.\n");
 140		return -EIO;
 141	}
 142	return 0;
 143}
 144
 145static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
 146{
 147	u32 chcr = chcr_read(sh_chan);
 148
 149	if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
 150		return true; /* working */
 151
 152	return false; /* waiting */
 153}
 154
 155static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
 156{
 157	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 158	struct sh_dmae_pdata *pdata = shdev->pdata;
 159	int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
 160		((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
 161
 162	if (cnt >= pdata->ts_shift_num)
 163		cnt = 0;
 164
 165	return pdata->ts_shift[cnt];
 166}
 167
 168static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
 169{
 170	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 171	struct sh_dmae_pdata *pdata = shdev->pdata;
 172	int i;
 173
 174	for (i = 0; i < pdata->ts_shift_num; i++)
 175		if (pdata->ts_shift[i] == l2size)
 176			break;
 177
 178	if (i == pdata->ts_shift_num)
 179		i = 0;
 180
 181	return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
 182		((i << pdata->ts_high_shift) & pdata->ts_high_mask);
 183}
 184
 185static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
 186{
 187	sh_dmae_writel(sh_chan, hw->sar, SAR);
 188	sh_dmae_writel(sh_chan, hw->dar, DAR);
 189	sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
 190}
 191
 192static void dmae_start(struct sh_dmae_chan *sh_chan)
 193{
 194	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 195	u32 chcr = chcr_read(sh_chan);
 196
 197	if (shdev->pdata->needs_tend_set)
 198		sh_dmae_writel(sh_chan, 0xFFFFFFFF, TEND);
 199
 200	chcr |= CHCR_DE | shdev->chcr_ie_bit;
 201	chcr_write(sh_chan, chcr & ~CHCR_TE);
 202}
 203
 204static void dmae_halt(struct sh_dmae_chan *sh_chan)
 205{
 206	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 207	u32 chcr = chcr_read(sh_chan);
 208
 209	chcr &= ~(CHCR_DE | CHCR_TE | shdev->chcr_ie_bit);
 210	chcr_write(sh_chan, chcr);
 211}
 212
 213static void dmae_init(struct sh_dmae_chan *sh_chan)
 214{
 215	/*
 216	 * Default configuration for dual address memory-memory transfer.
 217	 * 0x400 represents auto-request.
 218	 */
 219	u32 chcr = DM_INC | SM_INC | 0x400 | log2size_to_chcr(sh_chan,
 220						   LOG2_DEFAULT_XFER_SIZE);
 221	sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
 222	chcr_write(sh_chan, chcr);
 223}
 224
 225static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
 226{
 227	/* If DMA is active, cannot set CHCR. TODO: remove this superfluous check */
 228	if (dmae_is_busy(sh_chan))
 229		return -EBUSY;
 230
 231	sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
 232	chcr_write(sh_chan, val);
 233
 234	return 0;
 235}
 236
 237static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
 238{
 239	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 240	struct sh_dmae_pdata *pdata = shdev->pdata;
 241	const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->id];
 242	u16 __iomem *addr = shdev->dmars;
 243	unsigned int shift = chan_pdata->dmars_bit;
 244
 245	if (dmae_is_busy(sh_chan))
 246		return -EBUSY;
 247
 248	if (pdata->no_dmars)
 249		return 0;
 250
 251	/* in the case of a missing DMARS resource use first memory window */
 252	if (!addr)
 253		addr = (u16 __iomem *)shdev->chan_reg;
 254	addr += chan_pdata->dmars / sizeof(u16);
 255
 256	__raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
 257		     addr);
 258
 259	return 0;
 260}
 261
 262static dma_cookie_t sh_dmae_tx_submit(struct dma_async_tx_descriptor *tx)
 263{
 264	struct sh_desc *desc = tx_to_sh_desc(tx), *chunk, *last = desc, *c;
 265	struct sh_dmae_chan *sh_chan = to_sh_chan(tx->chan);
 266	dma_async_tx_callback callback = tx->callback;
 267	dma_cookie_t cookie;
 268
 269	spin_lock_bh(&sh_chan->desc_lock);
 270
 271	cookie = sh_chan->common.cookie;
 272	cookie++;
 273	if (cookie < 0)
 274		cookie = 1;
 275
 276	sh_chan->common.cookie = cookie;
 277	tx->cookie = cookie;
 278
 279	/* Mark all chunks of this descriptor as submitted, move to the queue */
 280	list_for_each_entry_safe(chunk, c, desc->node.prev, node) {
 281		/*
 282		 * All chunks are on the global ld_free, so, we have to find
 283		 * the end of the chain ourselves
 284		 */
 285		if (chunk != desc && (chunk->mark == DESC_IDLE ||
 286				      chunk->async_tx.cookie > 0 ||
 287				      chunk->async_tx.cookie == -EBUSY ||
 288				      &chunk->node == &sh_chan->ld_free))
 289			break;
 290		chunk->mark = DESC_SUBMITTED;
 291		/* Callback goes to the last chunk */
 292		chunk->async_tx.callback = NULL;
 293		chunk->cookie = cookie;
 294		list_move_tail(&chunk->node, &sh_chan->ld_queue);
 295		last = chunk;
 296	}
 297
 298	last->async_tx.callback = callback;
 299	last->async_tx.callback_param = tx->callback_param;
 300
 301	dev_dbg(sh_chan->dev, "submit #%d@%p on %d: %x[%d] -> %x\n",
 302		tx->cookie, &last->async_tx, sh_chan->id,
 303		desc->hw.sar, desc->hw.tcr, desc->hw.dar);
 304
 305	spin_unlock_bh(&sh_chan->desc_lock);
 306
 307	return cookie;
 308}
 309
 310/* Called with desc_lock held */
 311static struct sh_desc *sh_dmae_get_desc(struct sh_dmae_chan *sh_chan)
 312{
 313	struct sh_desc *desc;
 314
 315	list_for_each_entry(desc, &sh_chan->ld_free, node)
 316		if (desc->mark != DESC_PREPARED) {
 317			BUG_ON(desc->mark != DESC_IDLE);
 318			list_del(&desc->node);
 319			return desc;
 320		}
 321
 322	return NULL;
 323}
 324
 325static const struct sh_dmae_slave_config *sh_dmae_find_slave(
 326	struct sh_dmae_chan *sh_chan, struct sh_dmae_slave *param)
 327{
 328	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 329	struct sh_dmae_pdata *pdata = shdev->pdata;
 330	int i;
 331
 332	if (param->slave_id >= SH_DMA_SLAVE_NUMBER)
 333		return NULL;
 334
 335	for (i = 0; i < pdata->slave_num; i++)
 336		if (pdata->slave[i].slave_id == param->slave_id)
 337			return pdata->slave + i;
 338
 339	return NULL;
 340}
 341
 342static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
 343{
 344	struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
 345	struct sh_desc *desc;
 346	struct sh_dmae_slave *param = chan->private;
 347	int ret;
 348
 349	pm_runtime_get_sync(sh_chan->dev);
 350
 351	/*
 352	 * This relies on the guarantee from dmaengine that alloc_chan_resources
 353	 * never runs concurrently with itself or free_chan_resources.
 354	 */
 355	if (param) {
 356		const struct sh_dmae_slave_config *cfg;
 357
 358		cfg = sh_dmae_find_slave(sh_chan, param);
 359		if (!cfg) {
 360			ret = -EINVAL;
 361			goto efindslave;
 362		}
 363
 364		if (test_and_set_bit(param->slave_id, sh_dmae_slave_used)) {
 365			ret = -EBUSY;
 366			goto etestused;
 367		}
 368
 369		param->config = cfg;
 370
 371		dmae_set_dmars(sh_chan, cfg->mid_rid);
 372		dmae_set_chcr(sh_chan, cfg->chcr);
 373	} else {
 374		dmae_init(sh_chan);
 375	}
 376
 377	spin_lock_bh(&sh_chan->desc_lock);
 378	while (sh_chan->descs_allocated < NR_DESCS_PER_CHANNEL) {
 379		spin_unlock_bh(&sh_chan->desc_lock);
 380		desc = kzalloc(sizeof(struct sh_desc), GFP_KERNEL);
 381		if (!desc) {
 382			spin_lock_bh(&sh_chan->desc_lock);
 383			break;
 384		}
 385		dma_async_tx_descriptor_init(&desc->async_tx,
 386					&sh_chan->common);
 387		desc->async_tx.tx_submit = sh_dmae_tx_submit;
 388		desc->mark = DESC_IDLE;
 389
 390		spin_lock_bh(&sh_chan->desc_lock);
 391		list_add(&desc->node, &sh_chan->ld_free);
 392		sh_chan->descs_allocated++;
 393	}
 394	spin_unlock_bh(&sh_chan->desc_lock);
 395
 396	if (!sh_chan->descs_allocated) {
 397		ret = -ENOMEM;
 398		goto edescalloc;
 399	}
 400
 401	return sh_chan->descs_allocated;
 402
 403edescalloc:
 404	if (param)
 405		clear_bit(param->slave_id, sh_dmae_slave_used);
 406etestused:
 407efindslave:
 408	pm_runtime_put(sh_chan->dev);
 409	return ret;
 410}
 411
 412/*
 413 * sh_dma_free_chan_resources - Free all resources of the channel.
 414 */
 415static void sh_dmae_free_chan_resources(struct dma_chan *chan)
 416{
 417	struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
 418	struct sh_desc *desc, *_desc;
 419	LIST_HEAD(list);
 420	int descs = sh_chan->descs_allocated;
 421
 422	/* Protect against ISR */
 423	spin_lock_irq(&sh_chan->desc_lock);
 424	dmae_halt(sh_chan);
 425	spin_unlock_irq(&sh_chan->desc_lock);
 426
 427	/* Now no new interrupts will occur */
 428
 429	/* Prepared and not submitted descriptors can still be on the queue */
 430	if (!list_empty(&sh_chan->ld_queue))
 431		sh_dmae_chan_ld_cleanup(sh_chan, true);
 432
 433	if (chan->private) {
 434		/* The caller is holding dma_list_mutex */
 435		struct sh_dmae_slave *param = chan->private;
 436		clear_bit(param->slave_id, sh_dmae_slave_used);
 437		chan->private = NULL;
 438	}
 439
 440	spin_lock_bh(&sh_chan->desc_lock);
 441
 442	list_splice_init(&sh_chan->ld_free, &list);
 443	sh_chan->descs_allocated = 0;
 444
 445	spin_unlock_bh(&sh_chan->desc_lock);
 446
 447	if (descs > 0)
 448		pm_runtime_put(sh_chan->dev);
 449
 450	list_for_each_entry_safe(desc, _desc, &list, node)
 451		kfree(desc);
 452}
 453
 454/**
 455 * sh_dmae_add_desc - get, set up and return one transfer descriptor
 456 * @sh_chan:	DMA channel
 457 * @flags:	DMA transfer flags
 458 * @dest:	destination DMA address, incremented when direction equals
 459 *		DMA_FROM_DEVICE or DMA_BIDIRECTIONAL
 460 * @src:	source DMA address, incremented when direction equals
 461 *		DMA_TO_DEVICE or DMA_BIDIRECTIONAL
 462 * @len:	DMA transfer length
 463 * @first:	if NULL, set to the current descriptor and cookie set to -EBUSY
 464 * @direction:	needed for slave DMA to decide which address to keep constant,
 465 *		equals DMA_BIDIRECTIONAL for MEMCPY
 466 * Returns 0 or an error
 467 * Locks: called with desc_lock held
 468 */
 469static struct sh_desc *sh_dmae_add_desc(struct sh_dmae_chan *sh_chan,
 470	unsigned long flags, dma_addr_t *dest, dma_addr_t *src, size_t *len,
 471	struct sh_desc **first, enum dma_data_direction direction)
 472{
 473	struct sh_desc *new;
 474	size_t copy_size;
 475
 476	if (!*len)
 477		return NULL;
 478
 479	/* Allocate the link descriptor from the free list */
 480	new = sh_dmae_get_desc(sh_chan);
 481	if (!new) {
 482		dev_err(sh_chan->dev, "No free link descriptor available\n");
 483		return NULL;
 484	}
 485
 486	copy_size = min(*len, (size_t)SH_DMA_TCR_MAX + 1);
 487
 488	new->hw.sar = *src;
 489	new->hw.dar = *dest;
 490	new->hw.tcr = copy_size;
 491
 492	if (!*first) {
 493		/* First desc */
 494		new->async_tx.cookie = -EBUSY;
 495		*first = new;
 496	} else {
 497		/* Other desc - invisible to the user */
 498		new->async_tx.cookie = -EINVAL;
 499	}
 500
 501	dev_dbg(sh_chan->dev,
 502		"chaining (%u/%u)@%x -> %x with %p, cookie %d, shift %d\n",
 503		copy_size, *len, *src, *dest, &new->async_tx,
 504		new->async_tx.cookie, sh_chan->xmit_shift);
 505
 506	new->mark = DESC_PREPARED;
 507	new->async_tx.flags = flags;
 508	new->direction = direction;
 509
 510	*len -= copy_size;
 511	if (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE)
 512		*src += copy_size;
 513	if (direction == DMA_BIDIRECTIONAL || direction == DMA_FROM_DEVICE)
 514		*dest += copy_size;
 515
 516	return new;
 517}
 518
 519/*
 520 * sh_dmae_prep_sg - prepare transfer descriptors from an SG list
 521 *
 522 * Common routine for public (MEMCPY) and slave DMA. The MEMCPY case is also
 523 * converted to scatter-gather to guarantee consistent locking and a correct
 524 * list manipulation. For slave DMA direction carries the usual meaning, and,
 525 * logically, the SG list is RAM and the addr variable contains slave address,
 526 * e.g., the FIFO I/O register. For MEMCPY direction equals DMA_BIDIRECTIONAL
 527 * and the SG list contains only one element and points at the source buffer.
 528 */
 529static struct dma_async_tx_descriptor *sh_dmae_prep_sg(struct sh_dmae_chan *sh_chan,
 530	struct scatterlist *sgl, unsigned int sg_len, dma_addr_t *addr,
 531	enum dma_data_direction direction, unsigned long flags)
 532{
 533	struct scatterlist *sg;
 534	struct sh_desc *first = NULL, *new = NULL /* compiler... */;
 535	LIST_HEAD(tx_list);
 536	int chunks = 0;
 537	int i;
 538
 539	if (!sg_len)
 540		return NULL;
 541
 542	for_each_sg(sgl, sg, sg_len, i)
 543		chunks += (sg_dma_len(sg) + SH_DMA_TCR_MAX) /
 544			(SH_DMA_TCR_MAX + 1);
 545
 546	/* Have to lock the whole loop to protect against concurrent release */
 547	spin_lock_bh(&sh_chan->desc_lock);
 548
 549	/*
 550	 * Chaining:
 551	 * first descriptor is what user is dealing with in all API calls, its
 552	 *	cookie is at first set to -EBUSY, at tx-submit to a positive
 553	 *	number
 554	 * if more than one chunk is needed further chunks have cookie = -EINVAL
 555	 * the last chunk, if not equal to the first, has cookie = -ENOSPC
 556	 * all chunks are linked onto the tx_list head with their .node heads
 557	 *	only during this function, then they are immediately spliced
 558	 *	back onto the free list in form of a chain
 559	 */
 560	for_each_sg(sgl, sg, sg_len, i) {
 561		dma_addr_t sg_addr = sg_dma_address(sg);
 562		size_t len = sg_dma_len(sg);
 563
 564		if (!len)
 565			goto err_get_desc;
 566
 567		do {
 568			dev_dbg(sh_chan->dev, "Add SG #%d@%p[%d], dma %llx\n",
 569				i, sg, len, (unsigned long long)sg_addr);
 570
 571			if (direction == DMA_FROM_DEVICE)
 572				new = sh_dmae_add_desc(sh_chan, flags,
 573						&sg_addr, addr, &len, &first,
 574						direction);
 575			else
 576				new = sh_dmae_add_desc(sh_chan, flags,
 577						addr, &sg_addr, &len, &first,
 578						direction);
 579			if (!new)
 580				goto err_get_desc;
 581
 582			new->chunks = chunks--;
 583			list_add_tail(&new->node, &tx_list);
 584		} while (len);
 585	}
 586
 587	if (new != first)
 588		new->async_tx.cookie = -ENOSPC;
 589
 590	/* Put them back on the free list, so, they don't get lost */
 591	list_splice_tail(&tx_list, &sh_chan->ld_free);
 592
 593	spin_unlock_bh(&sh_chan->desc_lock);
 594
 595	return &first->async_tx;
 596
 597err_get_desc:
 598	list_for_each_entry(new, &tx_list, node)
 599		new->mark = DESC_IDLE;
 600	list_splice(&tx_list, &sh_chan->ld_free);
 601
 602	spin_unlock_bh(&sh_chan->desc_lock);
 603
 604	return NULL;
 605}
 606
 607static struct dma_async_tx_descriptor *sh_dmae_prep_memcpy(
 608	struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
 609	size_t len, unsigned long flags)
 610{
 611	struct sh_dmae_chan *sh_chan;
 612	struct scatterlist sg;
 613
 614	if (!chan || !len)
 615		return NULL;
 616
 617	sh_chan = to_sh_chan(chan);
 618
 619	sg_init_table(&sg, 1);
 620	sg_set_page(&sg, pfn_to_page(PFN_DOWN(dma_src)), len,
 621		    offset_in_page(dma_src));
 622	sg_dma_address(&sg) = dma_src;
 623	sg_dma_len(&sg) = len;
 624
 625	return sh_dmae_prep_sg(sh_chan, &sg, 1, &dma_dest, DMA_BIDIRECTIONAL,
 626			       flags);
 627}
 628
 629static struct dma_async_tx_descriptor *sh_dmae_prep_slave_sg(
 630	struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
 631	enum dma_data_direction direction, unsigned long flags)
 632{
 633	struct sh_dmae_slave *param;
 634	struct sh_dmae_chan *sh_chan;
 635	dma_addr_t slave_addr;
 636
 637	if (!chan)
 638		return NULL;
 639
 640	sh_chan = to_sh_chan(chan);
 641	param = chan->private;
 642
 643	/* Someone calling slave DMA on a public channel? */
 644	if (!param || !sg_len) {
 645		dev_warn(sh_chan->dev, "%s: bad parameter: %p, %d, %d\n",
 646			 __func__, param, sg_len, param ? param->slave_id : -1);
 647		return NULL;
 648	}
 649
 650	slave_addr = param->config->addr;
 651
 652	/*
 653	 * if (param != NULL), this is a successfully requested slave channel,
 654	 * therefore param->config != NULL too.
 655	 */
 656	return sh_dmae_prep_sg(sh_chan, sgl, sg_len, &slave_addr,
 657			       direction, flags);
 658}
 659
 660static int sh_dmae_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
 661			   unsigned long arg)
 662{
 663	struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
 664
 665	/* Only supports DMA_TERMINATE_ALL */
 666	if (cmd != DMA_TERMINATE_ALL)
 667		return -ENXIO;
 668
 669	if (!chan)
 670		return -EINVAL;
 671
 672	spin_lock_bh(&sh_chan->desc_lock);
 673	dmae_halt(sh_chan);
 674
 675	if (!list_empty(&sh_chan->ld_queue)) {
 676		/* Record partial transfer */
 677		struct sh_desc *desc = list_entry(sh_chan->ld_queue.next,
 678						  struct sh_desc, node);
 679		desc->partial = (desc->hw.tcr - sh_dmae_readl(sh_chan, TCR)) <<
 680			sh_chan->xmit_shift;
 681
 682	}
 683	spin_unlock_bh(&sh_chan->desc_lock);
 684
 685	sh_dmae_chan_ld_cleanup(sh_chan, true);
 686
 687	return 0;
 688}
 689
 690static dma_async_tx_callback __ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
 691{
 692	struct sh_desc *desc, *_desc;
 693	/* Is the "exposed" head of a chain acked? */
 694	bool head_acked = false;
 695	dma_cookie_t cookie = 0;
 696	dma_async_tx_callback callback = NULL;
 697	void *param = NULL;
 698
 699	spin_lock_bh(&sh_chan->desc_lock);
 700	list_for_each_entry_safe(desc, _desc, &sh_chan->ld_queue, node) {
 701		struct dma_async_tx_descriptor *tx = &desc->async_tx;
 702
 703		BUG_ON(tx->cookie > 0 && tx->cookie != desc->cookie);
 704		BUG_ON(desc->mark != DESC_SUBMITTED &&
 705		       desc->mark != DESC_COMPLETED &&
 706		       desc->mark != DESC_WAITING);
 707
 708		/*
 709		 * queue is ordered, and we use this loop to (1) clean up all
 710		 * completed descriptors, and to (2) update descriptor flags of
 711		 * any chunks in a (partially) completed chain
 712		 */
 713		if (!all && desc->mark == DESC_SUBMITTED &&
 714		    desc->cookie != cookie)
 715			break;
 716
 717		if (tx->cookie > 0)
 718			cookie = tx->cookie;
 719
 720		if (desc->mark == DESC_COMPLETED && desc->chunks == 1) {
 721			if (sh_chan->completed_cookie != desc->cookie - 1)
 722				dev_dbg(sh_chan->dev,
 723					"Completing cookie %d, expected %d\n",
 724					desc->cookie,
 725					sh_chan->completed_cookie + 1);
 726			sh_chan->completed_cookie = desc->cookie;
 727		}
 728
 729		/* Call callback on the last chunk */
 730		if (desc->mark == DESC_COMPLETED && tx->callback) {
 731			desc->mark = DESC_WAITING;
 732			callback = tx->callback;
 733			param = tx->callback_param;
 734			dev_dbg(sh_chan->dev, "descriptor #%d@%p on %d callback\n",
 735				tx->cookie, tx, sh_chan->id);
 736			BUG_ON(desc->chunks != 1);
 737			break;
 738		}
 739
 740		if (tx->cookie > 0 || tx->cookie == -EBUSY) {
 741			if (desc->mark == DESC_COMPLETED) {
 742				BUG_ON(tx->cookie < 0);
 743				desc->mark = DESC_WAITING;
 744			}
 745			head_acked = async_tx_test_ack(tx);
 746		} else {
 747			switch (desc->mark) {
 748			case DESC_COMPLETED:
 749				desc->mark = DESC_WAITING;
 750				/* Fall through */
 751			case DESC_WAITING:
 752				if (head_acked)
 753					async_tx_ack(&desc->async_tx);
 754			}
 755		}
 756
 757		dev_dbg(sh_chan->dev, "descriptor %p #%d completed.\n",
 758			tx, tx->cookie);
 759
 760		if (((desc->mark == DESC_COMPLETED ||
 761		      desc->mark == DESC_WAITING) &&
 762		     async_tx_test_ack(&desc->async_tx)) || all) {
 763			/* Remove from ld_queue list */
 764			desc->mark = DESC_IDLE;
 765			list_move(&desc->node, &sh_chan->ld_free);
 766		}
 767	}
 768
 769	if (all && !callback)
 770		/*
 771		 * Terminating and the loop completed normally: forgive
 772		 * uncompleted cookies
 773		 */
 774		sh_chan->completed_cookie = sh_chan->common.cookie;
 775
 776	spin_unlock_bh(&sh_chan->desc_lock);
 777
 778	if (callback)
 779		callback(param);
 780
 781	return callback;
 782}
 783
 784/*
 785 * sh_chan_ld_cleanup - Clean up link descriptors
 786 *
 787 * This function cleans up the ld_queue of DMA channel.
 788 */
 789static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
 790{
 791	while (__ld_cleanup(sh_chan, all))
 792		;
 793}
 794
 795static void sh_chan_xfer_ld_queue(struct sh_dmae_chan *sh_chan)
 796{
 797	struct sh_desc *desc;
 798
 799	spin_lock_bh(&sh_chan->desc_lock);
 800	/* DMA work check */
 801	if (dmae_is_busy(sh_chan))
 802		goto sh_chan_xfer_ld_queue_end;
 803
 804	/* Find the first not transferred descriptor */
 805	list_for_each_entry(desc, &sh_chan->ld_queue, node)
 806		if (desc->mark == DESC_SUBMITTED) {
 807			dev_dbg(sh_chan->dev, "Queue #%d to %d: %u@%x -> %x\n",
 808				desc->async_tx.cookie, sh_chan->id,
 809				desc->hw.tcr, desc->hw.sar, desc->hw.dar);
 810			/* Get the ld start address from ld_queue */
 811			dmae_set_reg(sh_chan, &desc->hw);
 812			dmae_start(sh_chan);
 813			break;
 814		}
 815
 816sh_chan_xfer_ld_queue_end:
 817	spin_unlock_bh(&sh_chan->desc_lock);
 818}
 819
 820static void sh_dmae_memcpy_issue_pending(struct dma_chan *chan)
 821{
 822	struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
 823	sh_chan_xfer_ld_queue(sh_chan);
 824}
 825
 826static enum dma_status sh_dmae_tx_status(struct dma_chan *chan,
 827					dma_cookie_t cookie,
 828					struct dma_tx_state *txstate)
 829{
 830	struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
 831	dma_cookie_t last_used;
 832	dma_cookie_t last_complete;
 833	enum dma_status status;
 834
 835	sh_dmae_chan_ld_cleanup(sh_chan, false);
 836
 837	/* First read completed cookie to avoid a skew */
 838	last_complete = sh_chan->completed_cookie;
 839	rmb();
 840	last_used = chan->cookie;
 841	BUG_ON(last_complete < 0);
 842	dma_set_tx_state(txstate, last_complete, last_used, 0);
 843
 844	spin_lock_bh(&sh_chan->desc_lock);
 845
 846	status = dma_async_is_complete(cookie, last_complete, last_used);
 847
 848	/*
 849	 * If we don't find cookie on the queue, it has been aborted and we have
 850	 * to report error
 851	 */
 852	if (status != DMA_SUCCESS) {
 853		struct sh_desc *desc;
 854		status = DMA_ERROR;
 855		list_for_each_entry(desc, &sh_chan->ld_queue, node)
 856			if (desc->cookie == cookie) {
 857				status = DMA_IN_PROGRESS;
 858				break;
 859			}
 860	}
 861
 862	spin_unlock_bh(&sh_chan->desc_lock);
 863
 864	return status;
 865}
 866
 867static irqreturn_t sh_dmae_interrupt(int irq, void *data)
 868{
 869	irqreturn_t ret = IRQ_NONE;
 870	struct sh_dmae_chan *sh_chan = data;
 871	u32 chcr;
 872
 873	spin_lock(&sh_chan->desc_lock);
 874
 875	chcr = chcr_read(sh_chan);
 876
 877	if (chcr & CHCR_TE) {
 878		/* DMA stop */
 879		dmae_halt(sh_chan);
 880
 881		ret = IRQ_HANDLED;
 882		tasklet_schedule(&sh_chan->tasklet);
 883	}
 884
 885	spin_unlock(&sh_chan->desc_lock);
 886
 887	return ret;
 888}
 889
 890/* Called from error IRQ or NMI */
 891static bool sh_dmae_reset(struct sh_dmae_device *shdev)
 892{
 893	unsigned int handled = 0;
 894	int i;
 895
 896	/* halt the dma controller */
 897	sh_dmae_ctl_stop(shdev);
 898
 899	/* We cannot detect, which channel caused the error, have to reset all */
 900	for (i = 0; i < SH_DMAC_MAX_CHANNELS; i++) {
 901		struct sh_dmae_chan *sh_chan = shdev->chan[i];
 902		struct sh_desc *desc;
 903		LIST_HEAD(dl);
 904
 905		if (!sh_chan)
 906			continue;
 907
 908		spin_lock(&sh_chan->desc_lock);
 909
 910		/* Stop the channel */
 911		dmae_halt(sh_chan);
 912
 913		list_splice_init(&sh_chan->ld_queue, &dl);
 914
 915		spin_unlock(&sh_chan->desc_lock);
 916
 917		/* Complete all  */
 918		list_for_each_entry(desc, &dl, node) {
 919			struct dma_async_tx_descriptor *tx = &desc->async_tx;
 920			desc->mark = DESC_IDLE;
 921			if (tx->callback)
 922				tx->callback(tx->callback_param);
 923		}
 924
 925		spin_lock(&sh_chan->desc_lock);
 926		list_splice(&dl, &sh_chan->ld_free);
 927		spin_unlock(&sh_chan->desc_lock);
 928
 929		handled++;
 930	}
 931
 932	sh_dmae_rst(shdev);
 933
 934	return !!handled;
 935}
 936
 937static irqreturn_t sh_dmae_err(int irq, void *data)
 938{
 939	struct sh_dmae_device *shdev = data;
 940
 941	if (!(dmaor_read(shdev) & DMAOR_AE))
 942		return IRQ_NONE;
 943
 944	sh_dmae_reset(data);
 945	return IRQ_HANDLED;
 946}
 947
 948static void dmae_do_tasklet(unsigned long data)
 949{
 950	struct sh_dmae_chan *sh_chan = (struct sh_dmae_chan *)data;
 951	struct sh_desc *desc;
 952	u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
 953	u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
 954
 955	spin_lock(&sh_chan->desc_lock);
 956	list_for_each_entry(desc, &sh_chan->ld_queue, node) {
 957		if (desc->mark == DESC_SUBMITTED &&
 958		    ((desc->direction == DMA_FROM_DEVICE &&
 959		      (desc->hw.dar + desc->hw.tcr) == dar_buf) ||
 960		     (desc->hw.sar + desc->hw.tcr) == sar_buf)) {
 961			dev_dbg(sh_chan->dev, "done #%d@%p dst %u\n",
 962				desc->async_tx.cookie, &desc->async_tx,
 963				desc->hw.dar);
 964			desc->mark = DESC_COMPLETED;
 965			break;
 966		}
 967	}
 968	spin_unlock(&sh_chan->desc_lock);
 969
 970	/* Next desc */
 971	sh_chan_xfer_ld_queue(sh_chan);
 972	sh_dmae_chan_ld_cleanup(sh_chan, false);
 973}
 974
 975static bool sh_dmae_nmi_notify(struct sh_dmae_device *shdev)
 976{
 977	/* Fast path out if NMIF is not asserted for this controller */
 978	if ((dmaor_read(shdev) & DMAOR_NMIF) == 0)
 979		return false;
 980
 981	return sh_dmae_reset(shdev);
 982}
 983
 984static int sh_dmae_nmi_handler(struct notifier_block *self,
 985			       unsigned long cmd, void *data)
 986{
 987	struct sh_dmae_device *shdev;
 988	int ret = NOTIFY_DONE;
 989	bool triggered;
 990
 991	/*
 992	 * Only concern ourselves with NMI events.
 993	 *
 994	 * Normally we would check the die chain value, but as this needs
 995	 * to be architecture independent, check for NMI context instead.
 996	 */
 997	if (!in_nmi())
 998		return NOTIFY_DONE;
 999
1000	rcu_read_lock();
1001	list_for_each_entry_rcu(shdev, &sh_dmae_devices, node) {
1002		/*
1003		 * Only stop if one of the controllers has NMIF asserted,
1004		 * we do not want to interfere with regular address error
1005		 * handling or NMI events that don't concern the DMACs.
1006		 */
1007		triggered = sh_dmae_nmi_notify(shdev);
1008		if (triggered == true)
1009			ret = NOTIFY_OK;
1010	}
1011	rcu_read_unlock();
1012
1013	return ret;
1014}
1015
1016static struct notifier_block sh_dmae_nmi_notifier __read_mostly = {
1017	.notifier_call	= sh_dmae_nmi_handler,
1018
1019	/* Run before NMI debug handler and KGDB */
1020	.priority	= 1,
1021};
1022
1023static int __devinit sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
1024					int irq, unsigned long flags)
1025{
1026	int err;
1027	const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
1028	struct platform_device *pdev = to_platform_device(shdev->common.dev);
1029	struct sh_dmae_chan *new_sh_chan;
1030
1031	/* alloc channel */
1032	new_sh_chan = kzalloc(sizeof(struct sh_dmae_chan), GFP_KERNEL);
1033	if (!new_sh_chan) {
1034		dev_err(shdev->common.dev,
1035			"No free memory for allocating dma channels!\n");
1036		return -ENOMEM;
1037	}
1038
1039	/* copy struct dma_device */
1040	new_sh_chan->common.device = &shdev->common;
1041
1042	new_sh_chan->dev = shdev->common.dev;
1043	new_sh_chan->id = id;
1044	new_sh_chan->irq = irq;
1045	new_sh_chan->base = shdev->chan_reg + chan_pdata->offset / sizeof(u32);
1046
1047	/* Init DMA tasklet */
1048	tasklet_init(&new_sh_chan->tasklet, dmae_do_tasklet,
1049			(unsigned long)new_sh_chan);
1050
1051	spin_lock_init(&new_sh_chan->desc_lock);
1052
1053	/* Init descripter manage list */
1054	INIT_LIST_HEAD(&new_sh_chan->ld_queue);
1055	INIT_LIST_HEAD(&new_sh_chan->ld_free);
1056
1057	/* Add the channel to DMA device channel list */
1058	list_add_tail(&new_sh_chan->common.device_node,
1059			&shdev->common.channels);
1060	shdev->common.chancnt++;
1061
1062	if (pdev->id >= 0)
1063		snprintf(new_sh_chan->dev_id, sizeof(new_sh_chan->dev_id),
1064			 "sh-dmae%d.%d", pdev->id, new_sh_chan->id);
1065	else
1066		snprintf(new_sh_chan->dev_id, sizeof(new_sh_chan->dev_id),
1067			 "sh-dma%d", new_sh_chan->id);
1068
1069	/* set up channel irq */
1070	err = request_irq(irq, &sh_dmae_interrupt, flags,
1071			  new_sh_chan->dev_id, new_sh_chan);
1072	if (err) {
1073		dev_err(shdev->common.dev, "DMA channel %d request_irq error "
1074			"with return %d\n", id, err);
1075		goto err_no_irq;
1076	}
1077
1078	shdev->chan[id] = new_sh_chan;
1079	return 0;
1080
1081err_no_irq:
1082	/* remove from dmaengine device node */
1083	list_del(&new_sh_chan->common.device_node);
1084	kfree(new_sh_chan);
1085	return err;
1086}
1087
1088static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
1089{
1090	int i;
1091
1092	for (i = shdev->common.chancnt - 1 ; i >= 0 ; i--) {
1093		if (shdev->chan[i]) {
1094			struct sh_dmae_chan *sh_chan = shdev->chan[i];
1095
1096			free_irq(sh_chan->irq, sh_chan);
1097
1098			list_del(&sh_chan->common.device_node);
1099			kfree(sh_chan);
1100			shdev->chan[i] = NULL;
1101		}
1102	}
1103	shdev->common.chancnt = 0;
1104}
1105
1106static int __init sh_dmae_probe(struct platform_device *pdev)
1107{
1108	struct sh_dmae_pdata *pdata = pdev->dev.platform_data;
1109	unsigned long irqflags = IRQF_DISABLED,
1110		chan_flag[SH_DMAC_MAX_CHANNELS] = {};
1111	int errirq, chan_irq[SH_DMAC_MAX_CHANNELS];
1112	int err, i, irq_cnt = 0, irqres = 0, irq_cap = 0;
1113	struct sh_dmae_device *shdev;
1114	struct resource *chan, *dmars, *errirq_res, *chanirq_res;
1115
1116	/* get platform data */
1117	if (!pdata || !pdata->channel_num)
1118		return -ENODEV;
1119
1120	chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1121	/* DMARS area is optional */
1122	dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1123	/*
1124	 * IRQ resources:
1125	 * 1. there always must be at least one IRQ IO-resource. On SH4 it is
1126	 *    the error IRQ, in which case it is the only IRQ in this resource:
1127	 *    start == end. If it is the only IRQ resource, all channels also
1128	 *    use the same IRQ.
1129	 * 2. DMA channel IRQ resources can be specified one per resource or in
1130	 *    ranges (start != end)
1131	 * 3. iff all events (channels and, optionally, error) on this
1132	 *    controller use the same IRQ, only one IRQ resource can be
1133	 *    specified, otherwise there must be one IRQ per channel, even if
1134	 *    some of them are equal
1135	 * 4. if all IRQs on this controller are equal or if some specific IRQs
1136	 *    specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
1137	 *    requested with the IRQF_SHARED flag
1138	 */
1139	errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1140	if (!chan || !errirq_res)
1141		return -ENODEV;
1142
1143	if (!request_mem_region(chan->start, resource_size(chan), pdev->name)) {
1144		dev_err(&pdev->dev, "DMAC register region already claimed\n");
1145		return -EBUSY;
1146	}
1147
1148	if (dmars && !request_mem_region(dmars->start, resource_size(dmars), pdev->name)) {
1149		dev_err(&pdev->dev, "DMAC DMARS region already claimed\n");
1150		err = -EBUSY;
1151		goto ermrdmars;
1152	}
1153
1154	err = -ENOMEM;
1155	shdev = kzalloc(sizeof(struct sh_dmae_device), GFP_KERNEL);
1156	if (!shdev) {
1157		dev_err(&pdev->dev, "Not enough memory\n");
1158		goto ealloc;
1159	}
1160
1161	shdev->chan_reg = ioremap(chan->start, resource_size(chan));
1162	if (!shdev->chan_reg)
1163		goto emapchan;
1164	if (dmars) {
1165		shdev->dmars = ioremap(dmars->start, resource_size(dmars));
1166		if (!shdev->dmars)
1167			goto emapdmars;
1168	}
1169
1170	/* platform data */
1171	shdev->pdata = pdata;
1172
1173	if (pdata->chcr_offset)
1174		shdev->chcr_offset = pdata->chcr_offset;
1175	else
1176		shdev->chcr_offset = CHCR;
1177
1178	if (pdata->chcr_ie_bit)
1179		shdev->chcr_ie_bit = pdata->chcr_ie_bit;
1180	else
1181		shdev->chcr_ie_bit = CHCR_IE;
1182
1183	platform_set_drvdata(pdev, shdev);
1184
1185	pm_runtime_enable(&pdev->dev);
1186	pm_runtime_get_sync(&pdev->dev);
1187
1188	spin_lock_irq(&sh_dmae_lock);
1189	list_add_tail_rcu(&shdev->node, &sh_dmae_devices);
1190	spin_unlock_irq(&sh_dmae_lock);
1191
1192	/* reset dma controller - only needed as a test */
1193	err = sh_dmae_rst(shdev);
1194	if (err)
1195		goto rst_err;
1196
1197	INIT_LIST_HEAD(&shdev->common.channels);
1198
1199	dma_cap_set(DMA_MEMCPY, shdev->common.cap_mask);
1200	if (pdata->slave && pdata->slave_num)
1201		dma_cap_set(DMA_SLAVE, shdev->common.cap_mask);
1202
1203	shdev->common.device_alloc_chan_resources
1204		= sh_dmae_alloc_chan_resources;
1205	shdev->common.device_free_chan_resources = sh_dmae_free_chan_resources;
1206	shdev->common.device_prep_dma_memcpy = sh_dmae_prep_memcpy;
1207	shdev->common.device_tx_status = sh_dmae_tx_status;
1208	shdev->common.device_issue_pending = sh_dmae_memcpy_issue_pending;
1209
1210	/* Compulsory for DMA_SLAVE fields */
1211	shdev->common.device_prep_slave_sg = sh_dmae_prep_slave_sg;
1212	shdev->common.device_control = sh_dmae_control;
1213
1214	shdev->common.dev = &pdev->dev;
1215	/* Default transfer size of 32 bytes requires 32-byte alignment */
1216	shdev->common.copy_align = LOG2_DEFAULT_XFER_SIZE;
1217
1218#if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
1219	chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
1220
1221	if (!chanirq_res)
1222		chanirq_res = errirq_res;
1223	else
1224		irqres++;
1225
1226	if (chanirq_res == errirq_res ||
1227	    (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
1228		irqflags = IRQF_SHARED;
1229
1230	errirq = errirq_res->start;
1231
1232	err = request_irq(errirq, sh_dmae_err, irqflags,
1233			  "DMAC Address Error", shdev);
1234	if (err) {
1235		dev_err(&pdev->dev,
1236			"DMA failed requesting irq #%d, error %d\n",
1237			errirq, err);
1238		goto eirq_err;
1239	}
1240
1241#else
1242	chanirq_res = errirq_res;
1243#endif /* CONFIG_CPU_SH4 || CONFIG_ARCH_SHMOBILE */
1244
1245	if (chanirq_res->start == chanirq_res->end &&
1246	    !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
1247		/* Special case - all multiplexed */
1248		for (; irq_cnt < pdata->channel_num; irq_cnt++) {
1249			if (irq_cnt < SH_DMAC_MAX_CHANNELS) {
1250				chan_irq[irq_cnt] = chanirq_res->start;
1251				chan_flag[irq_cnt] = IRQF_SHARED;
1252			} else {
1253				irq_cap = 1;
1254				break;
1255			}
1256		}
1257	} else {
1258		do {
1259			for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
1260				if (irq_cnt >= SH_DMAC_MAX_CHANNELS) {
1261					irq_cap = 1;
1262					break;
1263				}
1264
1265				if ((errirq_res->flags & IORESOURCE_BITS) ==
1266				    IORESOURCE_IRQ_SHAREABLE)
1267					chan_flag[irq_cnt] = IRQF_SHARED;
1268				else
1269					chan_flag[irq_cnt] = IRQF_DISABLED;
1270				dev_dbg(&pdev->dev,
1271					"Found IRQ %d for channel %d\n",
1272					i, irq_cnt);
1273				chan_irq[irq_cnt++] = i;
1274			}
1275
1276			if (irq_cnt >= SH_DMAC_MAX_CHANNELS)
1277				break;
1278
1279			chanirq_res = platform_get_resource(pdev,
1280						IORESOURCE_IRQ, ++irqres);
1281		} while (irq_cnt < pdata->channel_num && chanirq_res);
1282	}
1283
1284	/* Create DMA Channel */
1285	for (i = 0; i < irq_cnt; i++) {
1286		err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
1287		if (err)
1288			goto chan_probe_err;
1289	}
1290
1291	if (irq_cap)
1292		dev_notice(&pdev->dev, "Attempting to register %d DMA "
1293			   "channels when a maximum of %d are supported.\n",
1294			   pdata->channel_num, SH_DMAC_MAX_CHANNELS);
1295
1296	pm_runtime_put(&pdev->dev);
1297
1298	dma_async_device_register(&shdev->common);
1299
1300	return err;
1301
1302chan_probe_err:
1303	sh_dmae_chan_remove(shdev);
1304
1305#if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
1306	free_irq(errirq, shdev);
1307eirq_err:
1308#endif
1309rst_err:
1310	spin_lock_irq(&sh_dmae_lock);
1311	list_del_rcu(&shdev->node);
1312	spin_unlock_irq(&sh_dmae_lock);
1313
1314	pm_runtime_put(&pdev->dev);
1315	pm_runtime_disable(&pdev->dev);
1316
1317	if (dmars)
1318		iounmap(shdev->dmars);
1319
1320	platform_set_drvdata(pdev, NULL);
1321emapdmars:
1322	iounmap(shdev->chan_reg);
1323	synchronize_rcu();
1324emapchan:
1325	kfree(shdev);
1326ealloc:
1327	if (dmars)
1328		release_mem_region(dmars->start, resource_size(dmars));
1329ermrdmars:
1330	release_mem_region(chan->start, resource_size(chan));
1331
1332	return err;
1333}
1334
1335static int __exit sh_dmae_remove(struct platform_device *pdev)
1336{
1337	struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
1338	struct resource *res;
1339	int errirq = platform_get_irq(pdev, 0);
1340
1341	dma_async_device_unregister(&shdev->common);
1342
1343	if (errirq > 0)
1344		free_irq(errirq, shdev);
1345
1346	spin_lock_irq(&sh_dmae_lock);
1347	list_del_rcu(&shdev->node);
1348	spin_unlock_irq(&sh_dmae_lock);
1349
1350	/* channel data remove */
1351	sh_dmae_chan_remove(shdev);
1352
1353	pm_runtime_disable(&pdev->dev);
1354
1355	if (shdev->dmars)
1356		iounmap(shdev->dmars);
1357	iounmap(shdev->chan_reg);
1358
1359	platform_set_drvdata(pdev, NULL);
1360
1361	synchronize_rcu();
1362	kfree(shdev);
1363
1364	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1365	if (res)
1366		release_mem_region(res->start, resource_size(res));
1367	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1368	if (res)
1369		release_mem_region(res->start, resource_size(res));
1370
1371	return 0;
1372}
1373
1374static void sh_dmae_shutdown(struct platform_device *pdev)
1375{
1376	struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
1377	sh_dmae_ctl_stop(shdev);
1378}
1379
1380static int sh_dmae_runtime_suspend(struct device *dev)
1381{
1382	return 0;
1383}
1384
1385static int sh_dmae_runtime_resume(struct device *dev)
1386{
1387	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
1388
1389	return sh_dmae_rst(shdev);
1390}
1391
1392#ifdef CONFIG_PM
1393static int sh_dmae_suspend(struct device *dev)
1394{
1395	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
1396	int i;
1397
1398	for (i = 0; i < shdev->pdata->channel_num; i++) {
1399		struct sh_dmae_chan *sh_chan = shdev->chan[i];
1400		if (sh_chan->descs_allocated)
1401			sh_chan->pm_error = pm_runtime_put_sync(dev);
1402	}
1403
1404	return 0;
1405}
1406
1407static int sh_dmae_resume(struct device *dev)
1408{
1409	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
1410	int i;
1411
1412	for (i = 0; i < shdev->pdata->channel_num; i++) {
1413		struct sh_dmae_chan *sh_chan = shdev->chan[i];
1414		struct sh_dmae_slave *param = sh_chan->common.private;
1415
1416		if (!sh_chan->descs_allocated)
1417			continue;
1418
1419		if (!sh_chan->pm_error)
1420			pm_runtime_get_sync(dev);
1421
1422		if (param) {
1423			const struct sh_dmae_slave_config *cfg = param->config;
1424			dmae_set_dmars(sh_chan, cfg->mid_rid);
1425			dmae_set_chcr(sh_chan, cfg->chcr);
1426		} else {
1427			dmae_init(sh_chan);
1428		}
1429	}
1430
1431	return 0;
1432}
1433#else
1434#define sh_dmae_suspend NULL
1435#define sh_dmae_resume NULL
1436#endif
1437
1438const struct dev_pm_ops sh_dmae_pm = {
1439	.suspend		= sh_dmae_suspend,
1440	.resume			= sh_dmae_resume,
1441	.runtime_suspend	= sh_dmae_runtime_suspend,
1442	.runtime_resume		= sh_dmae_runtime_resume,
1443};
1444
1445static struct platform_driver sh_dmae_driver = {
1446	.remove		= __exit_p(sh_dmae_remove),
1447	.shutdown	= sh_dmae_shutdown,
1448	.driver = {
1449		.owner	= THIS_MODULE,
1450		.name	= "sh-dma-engine",
1451		.pm	= &sh_dmae_pm,
1452	},
1453};
1454
1455static int __init sh_dmae_init(void)
1456{
1457	/* Wire up NMI handling */
1458	int err = register_die_notifier(&sh_dmae_nmi_notifier);
1459	if (err)
1460		return err;
1461
1462	return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
1463}
1464module_init(sh_dmae_init);
1465
1466static void __exit sh_dmae_exit(void)
1467{
1468	platform_driver_unregister(&sh_dmae_driver);
1469
1470	unregister_die_notifier(&sh_dmae_nmi_notifier);
1471}
1472module_exit(sh_dmae_exit);
1473
1474MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
1475MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
1476MODULE_LICENSE("GPL");
1477MODULE_ALIAS("platform:sh-dma-engine");