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v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * DMA driver for Nvidia's Tegra20 APB DMA controller.
   4 *
   5 * Copyright (c) 2012-2013, NVIDIA CORPORATION.  All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
   6 */
   7
   8#include <linux/bitops.h>
   9#include <linux/clk.h>
  10#include <linux/delay.h>
  11#include <linux/dmaengine.h>
  12#include <linux/dma-mapping.h>
  13#include <linux/err.h>
  14#include <linux/init.h>
  15#include <linux/interrupt.h>
  16#include <linux/io.h>
  17#include <linux/mm.h>
  18#include <linux/module.h>
  19#include <linux/of.h>
  20#include <linux/of_device.h>
  21#include <linux/of_dma.h>
  22#include <linux/platform_device.h>
  23#include <linux/pm.h>
  24#include <linux/pm_runtime.h>
  25#include <linux/reset.h>
  26#include <linux/slab.h>
  27#include <linux/wait.h>
  28
  29#include "dmaengine.h"
  30
  31#define CREATE_TRACE_POINTS
  32#include <trace/events/tegra_apb_dma.h>
  33
  34#define TEGRA_APBDMA_GENERAL			0x0
  35#define TEGRA_APBDMA_GENERAL_ENABLE		BIT(31)
  36
  37#define TEGRA_APBDMA_CONTROL			0x010
  38#define TEGRA_APBDMA_IRQ_MASK			0x01c
  39#define TEGRA_APBDMA_IRQ_MASK_SET		0x020
  40
  41/* CSR register */
  42#define TEGRA_APBDMA_CHAN_CSR			0x00
  43#define TEGRA_APBDMA_CSR_ENB			BIT(31)
  44#define TEGRA_APBDMA_CSR_IE_EOC			BIT(30)
  45#define TEGRA_APBDMA_CSR_HOLD			BIT(29)
  46#define TEGRA_APBDMA_CSR_DIR			BIT(28)
  47#define TEGRA_APBDMA_CSR_ONCE			BIT(27)
  48#define TEGRA_APBDMA_CSR_FLOW			BIT(21)
  49#define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT		16
  50#define TEGRA_APBDMA_CSR_REQ_SEL_MASK		0x1F
  51#define TEGRA_APBDMA_CSR_WCOUNT_MASK		0xFFFC
  52
  53/* STATUS register */
  54#define TEGRA_APBDMA_CHAN_STATUS		0x004
  55#define TEGRA_APBDMA_STATUS_BUSY		BIT(31)
  56#define TEGRA_APBDMA_STATUS_ISE_EOC		BIT(30)
  57#define TEGRA_APBDMA_STATUS_HALT		BIT(29)
  58#define TEGRA_APBDMA_STATUS_PING_PONG		BIT(28)
  59#define TEGRA_APBDMA_STATUS_COUNT_SHIFT		2
  60#define TEGRA_APBDMA_STATUS_COUNT_MASK		0xFFFC
  61
  62#define TEGRA_APBDMA_CHAN_CSRE			0x00C
  63#define TEGRA_APBDMA_CHAN_CSRE_PAUSE		BIT(31)
  64
  65/* AHB memory address */
  66#define TEGRA_APBDMA_CHAN_AHBPTR		0x010
  67
  68/* AHB sequence register */
  69#define TEGRA_APBDMA_CHAN_AHBSEQ		0x14
  70#define TEGRA_APBDMA_AHBSEQ_INTR_ENB		BIT(31)
  71#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8		(0 << 28)
  72#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16	(1 << 28)
  73#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32	(2 << 28)
  74#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64	(3 << 28)
  75#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128	(4 << 28)
  76#define TEGRA_APBDMA_AHBSEQ_DATA_SWAP		BIT(27)
  77#define TEGRA_APBDMA_AHBSEQ_BURST_1		(4 << 24)
  78#define TEGRA_APBDMA_AHBSEQ_BURST_4		(5 << 24)
  79#define TEGRA_APBDMA_AHBSEQ_BURST_8		(6 << 24)
  80#define TEGRA_APBDMA_AHBSEQ_DBL_BUF		BIT(19)
  81#define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT		16
  82#define TEGRA_APBDMA_AHBSEQ_WRAP_NONE		0
  83
  84/* APB address */
  85#define TEGRA_APBDMA_CHAN_APBPTR		0x018
  86
  87/* APB sequence register */
  88#define TEGRA_APBDMA_CHAN_APBSEQ		0x01c
  89#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8		(0 << 28)
  90#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16	(1 << 28)
  91#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32	(2 << 28)
  92#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64	(3 << 28)
  93#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128	(4 << 28)
  94#define TEGRA_APBDMA_APBSEQ_DATA_SWAP		BIT(27)
  95#define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1		(1 << 16)
  96
  97/* Tegra148 specific registers */
  98#define TEGRA_APBDMA_CHAN_WCOUNT		0x20
  99
 100#define TEGRA_APBDMA_CHAN_WORD_TRANSFER		0x24
 101
 102/*
 103 * If any burst is in flight and DMA paused then this is the time to complete
 104 * on-flight burst and update DMA status register.
 105 */
 106#define TEGRA_APBDMA_BURST_COMPLETE_TIME	20
 107
 108/* Channel base address offset from APBDMA base address */
 109#define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET	0x1000
 110
 111#define TEGRA_APBDMA_SLAVE_ID_INVALID	(TEGRA_APBDMA_CSR_REQ_SEL_MASK + 1)
 112
 113struct tegra_dma;
 114
 115/*
 116 * tegra_dma_chip_data Tegra chip specific DMA data
 117 * @nr_channels: Number of channels available in the controller.
 118 * @channel_reg_size: Channel register size/stride.
 119 * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
 120 * @support_channel_pause: Support channel wise pause of dma.
 121 * @support_separate_wcount_reg: Support separate word count register.
 122 */
 123struct tegra_dma_chip_data {
 124	unsigned int nr_channels;
 125	unsigned int channel_reg_size;
 126	unsigned int max_dma_count;
 127	bool support_channel_pause;
 128	bool support_separate_wcount_reg;
 129};
 130
 131/* DMA channel registers */
 132struct tegra_dma_channel_regs {
 133	u32 csr;
 134	u32 ahb_ptr;
 135	u32 apb_ptr;
 136	u32 ahb_seq;
 137	u32 apb_seq;
 138	u32 wcount;
 139};
 140
 141/*
 142 * tegra_dma_sg_req: DMA request details to configure hardware. This
 143 * contains the details for one transfer to configure DMA hw.
 144 * The client's request for data transfer can be broken into multiple
 145 * sub-transfer as per requester details and hw support.
 146 * This sub transfer get added in the list of transfer and point to Tegra
 147 * DMA descriptor which manages the transfer details.
 148 */
 149struct tegra_dma_sg_req {
 150	struct tegra_dma_channel_regs	ch_regs;
 151	unsigned int			req_len;
 152	bool				configured;
 153	bool				last_sg;
 154	struct list_head		node;
 155	struct tegra_dma_desc		*dma_desc;
 156	unsigned int			words_xferred;
 157};
 158
 159/*
 160 * tegra_dma_desc: Tegra DMA descriptors which manages the client requests.
 161 * This descriptor keep track of transfer status, callbacks and request
 162 * counts etc.
 163 */
 164struct tegra_dma_desc {
 165	struct dma_async_tx_descriptor	txd;
 166	unsigned int			bytes_requested;
 167	unsigned int			bytes_transferred;
 168	enum dma_status			dma_status;
 169	struct list_head		node;
 170	struct list_head		tx_list;
 171	struct list_head		cb_node;
 172	unsigned int			cb_count;
 173};
 174
 175struct tegra_dma_channel;
 176
 177typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc,
 178				bool to_terminate);
 179
 180/* tegra_dma_channel: Channel specific information */
 181struct tegra_dma_channel {
 182	struct dma_chan		dma_chan;
 183	char			name[12];
 184	bool			config_init;
 185	unsigned int		id;
 
 186	void __iomem		*chan_addr;
 187	spinlock_t		lock;
 188	bool			busy;
 189	struct tegra_dma	*tdma;
 190	bool			cyclic;
 191
 192	/* Different lists for managing the requests */
 193	struct list_head	free_sg_req;
 194	struct list_head	pending_sg_req;
 195	struct list_head	free_dma_desc;
 196	struct list_head	cb_desc;
 197
 198	/* ISR handler and tasklet for bottom half of isr handling */
 199	dma_isr_handler		isr_handler;
 200	struct tasklet_struct	tasklet;
 201
 202	/* Channel-slave specific configuration */
 203	unsigned int slave_id;
 204	struct dma_slave_config dma_sconfig;
 205	struct tegra_dma_channel_regs channel_reg;
 206
 207	struct wait_queue_head wq;
 208};
 209
 210/* tegra_dma: Tegra DMA specific information */
 211struct tegra_dma {
 212	struct dma_device		dma_dev;
 213	struct device			*dev;
 214	struct clk			*dma_clk;
 215	struct reset_control		*rst;
 216	spinlock_t			global_lock;
 217	void __iomem			*base_addr;
 218	const struct tegra_dma_chip_data *chip_data;
 219
 220	/*
 221	 * Counter for managing global pausing of the DMA controller.
 222	 * Only applicable for devices that don't support individual
 223	 * channel pausing.
 224	 */
 225	u32				global_pause_count;
 226
 
 
 
 227	/* Last member of the structure */
 228	struct tegra_dma_channel channels[];
 229};
 230
 231static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
 232{
 233	writel(val, tdma->base_addr + reg);
 234}
 235
 236static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
 237{
 238	return readl(tdma->base_addr + reg);
 239}
 240
 241static inline void tdc_write(struct tegra_dma_channel *tdc,
 242			     u32 reg, u32 val)
 243{
 244	writel(val, tdc->chan_addr + reg);
 245}
 246
 247static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
 248{
 249	return readl(tdc->chan_addr + reg);
 250}
 251
 252static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc)
 253{
 254	return container_of(dc, struct tegra_dma_channel, dma_chan);
 255}
 256
 257static inline struct tegra_dma_desc *
 258txd_to_tegra_dma_desc(struct dma_async_tx_descriptor *td)
 259{
 260	return container_of(td, struct tegra_dma_desc, txd);
 261}
 262
 263static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
 264{
 265	return &tdc->dma_chan.dev->device;
 266}
 267
 268static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx);
 
 
 269
 270/* Get DMA desc from free list, if not there then allocate it.  */
 271static struct tegra_dma_desc *tegra_dma_desc_get(struct tegra_dma_channel *tdc)
 
 272{
 273	struct tegra_dma_desc *dma_desc;
 274	unsigned long flags;
 275
 276	spin_lock_irqsave(&tdc->lock, flags);
 277
 278	/* Do not allocate if desc are waiting for ack */
 279	list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
 280		if (async_tx_test_ack(&dma_desc->txd) && !dma_desc->cb_count) {
 281			list_del(&dma_desc->node);
 282			spin_unlock_irqrestore(&tdc->lock, flags);
 283			dma_desc->txd.flags = 0;
 284			return dma_desc;
 285		}
 286	}
 287
 288	spin_unlock_irqrestore(&tdc->lock, flags);
 289
 290	/* Allocate DMA desc */
 291	dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT);
 292	if (!dma_desc)
 293		return NULL;
 294
 295	dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan);
 296	dma_desc->txd.tx_submit = tegra_dma_tx_submit;
 297	dma_desc->txd.flags = 0;
 298
 299	return dma_desc;
 300}
 301
 302static void tegra_dma_desc_put(struct tegra_dma_channel *tdc,
 303			       struct tegra_dma_desc *dma_desc)
 304{
 305	unsigned long flags;
 306
 307	spin_lock_irqsave(&tdc->lock, flags);
 308	if (!list_empty(&dma_desc->tx_list))
 309		list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req);
 310	list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 311	spin_unlock_irqrestore(&tdc->lock, flags);
 312}
 313
 314static struct tegra_dma_sg_req *
 315tegra_dma_sg_req_get(struct tegra_dma_channel *tdc)
 316{
 317	struct tegra_dma_sg_req *sg_req;
 318	unsigned long flags;
 319
 320	spin_lock_irqsave(&tdc->lock, flags);
 321	if (!list_empty(&tdc->free_sg_req)) {
 322		sg_req = list_first_entry(&tdc->free_sg_req, typeof(*sg_req),
 323					  node);
 324		list_del(&sg_req->node);
 325		spin_unlock_irqrestore(&tdc->lock, flags);
 326		return sg_req;
 327	}
 328	spin_unlock_irqrestore(&tdc->lock, flags);
 329
 330	sg_req = kzalloc(sizeof(*sg_req), GFP_NOWAIT);
 331
 332	return sg_req;
 333}
 334
 335static int tegra_dma_slave_config(struct dma_chan *dc,
 336				  struct dma_slave_config *sconfig)
 337{
 338	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 339
 340	if (!list_empty(&tdc->pending_sg_req)) {
 341		dev_err(tdc2dev(tdc), "Configuration not allowed\n");
 342		return -EBUSY;
 343	}
 344
 345	memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
 346	if (tdc->slave_id == TEGRA_APBDMA_SLAVE_ID_INVALID &&
 347	    sconfig->device_fc) {
 348		if (sconfig->slave_id > TEGRA_APBDMA_CSR_REQ_SEL_MASK)
 349			return -EINVAL;
 350		tdc->slave_id = sconfig->slave_id;
 351	}
 352	tdc->config_init = true;
 353
 354	return 0;
 355}
 356
 357static void tegra_dma_global_pause(struct tegra_dma_channel *tdc,
 358				   bool wait_for_burst_complete)
 359{
 360	struct tegra_dma *tdma = tdc->tdma;
 361
 362	spin_lock(&tdma->global_lock);
 363
 364	if (tdc->tdma->global_pause_count == 0) {
 365		tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0);
 366		if (wait_for_burst_complete)
 367			udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 368	}
 369
 370	tdc->tdma->global_pause_count++;
 371
 372	spin_unlock(&tdma->global_lock);
 373}
 374
 375static void tegra_dma_global_resume(struct tegra_dma_channel *tdc)
 376{
 377	struct tegra_dma *tdma = tdc->tdma;
 378
 379	spin_lock(&tdma->global_lock);
 380
 381	if (WARN_ON(tdc->tdma->global_pause_count == 0))
 382		goto out;
 383
 384	if (--tdc->tdma->global_pause_count == 0)
 385		tdma_write(tdma, TEGRA_APBDMA_GENERAL,
 386			   TEGRA_APBDMA_GENERAL_ENABLE);
 387
 388out:
 389	spin_unlock(&tdma->global_lock);
 390}
 391
 392static void tegra_dma_pause(struct tegra_dma_channel *tdc,
 393			    bool wait_for_burst_complete)
 394{
 395	struct tegra_dma *tdma = tdc->tdma;
 396
 397	if (tdma->chip_data->support_channel_pause) {
 398		tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE,
 399			  TEGRA_APBDMA_CHAN_CSRE_PAUSE);
 400		if (wait_for_burst_complete)
 401			udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 402	} else {
 403		tegra_dma_global_pause(tdc, wait_for_burst_complete);
 404	}
 405}
 406
 407static void tegra_dma_resume(struct tegra_dma_channel *tdc)
 408{
 409	struct tegra_dma *tdma = tdc->tdma;
 410
 411	if (tdma->chip_data->support_channel_pause)
 412		tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0);
 413	else
 414		tegra_dma_global_resume(tdc);
 
 415}
 416
 417static void tegra_dma_stop(struct tegra_dma_channel *tdc)
 418{
 419	u32 csr, status;
 
 420
 421	/* Disable interrupts */
 422	csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
 423	csr &= ~TEGRA_APBDMA_CSR_IE_EOC;
 424	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
 425
 426	/* Disable DMA */
 427	csr &= ~TEGRA_APBDMA_CSR_ENB;
 428	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
 429
 430	/* Clear interrupt status if it is there */
 431	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 432	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 433		dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
 434		tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 435	}
 436	tdc->busy = false;
 437}
 438
 439static void tegra_dma_start(struct tegra_dma_channel *tdc,
 440			    struct tegra_dma_sg_req *sg_req)
 441{
 442	struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs;
 443
 444	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr);
 445	tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq);
 446	tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr);
 447	tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq);
 448	tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr);
 449	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 450		tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_regs->wcount);
 451
 452	/* Start DMA */
 453	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
 454		  ch_regs->csr | TEGRA_APBDMA_CSR_ENB);
 455}
 456
 457static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc,
 458					 struct tegra_dma_sg_req *nsg_req)
 459{
 460	unsigned long status;
 461
 462	/*
 463	 * The DMA controller reloads the new configuration for next transfer
 464	 * after last burst of current transfer completes.
 465	 * If there is no IEC status then this makes sure that last burst
 466	 * has not be completed. There may be case that last burst is on
 467	 * flight and so it can complete but because DMA is paused, it
 468	 * will not generates interrupt as well as not reload the new
 469	 * configuration.
 470	 * If there is already IEC status then interrupt handler need to
 471	 * load new configuration.
 472	 */
 473	tegra_dma_pause(tdc, false);
 474	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 475
 476	/*
 477	 * If interrupt is pending then do nothing as the ISR will handle
 478	 * the programing for new request.
 479	 */
 480	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 481		dev_err(tdc2dev(tdc),
 482			"Skipping new configuration as interrupt is pending\n");
 483		tegra_dma_resume(tdc);
 484		return;
 485	}
 486
 487	/* Safe to program new configuration */
 488	tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr);
 489	tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr);
 490	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 491		tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
 492			  nsg_req->ch_regs.wcount);
 493	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
 494		  nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB);
 495	nsg_req->configured = true;
 496	nsg_req->words_xferred = 0;
 497
 498	tegra_dma_resume(tdc);
 499}
 500
 501static void tdc_start_head_req(struct tegra_dma_channel *tdc)
 502{
 503	struct tegra_dma_sg_req *sg_req;
 504
 505	sg_req = list_first_entry(&tdc->pending_sg_req, typeof(*sg_req), node);
 
 
 
 
 506	tegra_dma_start(tdc, sg_req);
 507	sg_req->configured = true;
 508	sg_req->words_xferred = 0;
 509	tdc->busy = true;
 510}
 511
 512static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
 513{
 514	struct tegra_dma_sg_req *hsgreq, *hnsgreq;
 
 
 
 
 515
 516	hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
 517	if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) {
 518		hnsgreq = list_first_entry(&hsgreq->node, typeof(*hnsgreq),
 519					   node);
 520		tegra_dma_configure_for_next(tdc, hnsgreq);
 521	}
 522}
 523
 524static inline unsigned int
 525get_current_xferred_count(struct tegra_dma_channel *tdc,
 526			  struct tegra_dma_sg_req *sg_req,
 527			  unsigned long status)
 528{
 529	return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4;
 530}
 531
 532static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
 533{
 534	struct tegra_dma_desc *dma_desc;
 535	struct tegra_dma_sg_req *sgreq;
 
 536
 537	while (!list_empty(&tdc->pending_sg_req)) {
 538		sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq),
 539					 node);
 540		list_move_tail(&sgreq->node, &tdc->free_sg_req);
 541		if (sgreq->last_sg) {
 542			dma_desc = sgreq->dma_desc;
 543			dma_desc->dma_status = DMA_ERROR;
 544			list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 545
 546			/* Add in cb list if it is not there. */
 547			if (!dma_desc->cb_count)
 548				list_add_tail(&dma_desc->cb_node,
 549					      &tdc->cb_desc);
 550			dma_desc->cb_count++;
 551		}
 552	}
 553	tdc->isr_handler = NULL;
 554}
 555
 556static bool handle_continuous_head_request(struct tegra_dma_channel *tdc,
 557					   bool to_terminate)
 558{
 559	struct tegra_dma_sg_req *hsgreq;
 
 
 
 
 
 
 560
 561	/*
 562	 * Check that head req on list should be in flight.
 563	 * If it is not in flight then abort transfer as
 564	 * looping of transfer can not continue.
 565	 */
 566	hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
 567	if (!hsgreq->configured) {
 568		tegra_dma_stop(tdc);
 569		pm_runtime_put(tdc->tdma->dev);
 570		dev_err(tdc2dev(tdc), "DMA transfer underflow, aborting DMA\n");
 571		tegra_dma_abort_all(tdc);
 572		return false;
 573	}
 574
 575	/* Configure next request */
 576	if (!to_terminate)
 577		tdc_configure_next_head_desc(tdc);
 578
 579	return true;
 580}
 581
 582static void handle_once_dma_done(struct tegra_dma_channel *tdc,
 583				 bool to_terminate)
 584{
 585	struct tegra_dma_desc *dma_desc;
 586	struct tegra_dma_sg_req *sgreq;
 
 587
 588	tdc->busy = false;
 589	sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
 590	dma_desc = sgreq->dma_desc;
 591	dma_desc->bytes_transferred += sgreq->req_len;
 592
 593	list_del(&sgreq->node);
 594	if (sgreq->last_sg) {
 595		dma_desc->dma_status = DMA_COMPLETE;
 596		dma_cookie_complete(&dma_desc->txd);
 597		if (!dma_desc->cb_count)
 598			list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
 599		dma_desc->cb_count++;
 600		list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 601	}
 602	list_add_tail(&sgreq->node, &tdc->free_sg_req);
 603
 604	/* Do not start DMA if it is going to be terminate */
 605	if (to_terminate)
 606		return;
 607
 608	if (list_empty(&tdc->pending_sg_req)) {
 609		pm_runtime_put(tdc->tdma->dev);
 610		return;
 611	}
 612
 613	tdc_start_head_req(tdc);
 614}
 615
 616static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
 617					    bool to_terminate)
 618{
 619	struct tegra_dma_desc *dma_desc;
 620	struct tegra_dma_sg_req *sgreq;
 
 621	bool st;
 622
 623	sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
 624	dma_desc = sgreq->dma_desc;
 625	/* if we dma for long enough the transfer count will wrap */
 626	dma_desc->bytes_transferred =
 627		(dma_desc->bytes_transferred + sgreq->req_len) %
 628		dma_desc->bytes_requested;
 629
 630	/* Callback need to be call */
 631	if (!dma_desc->cb_count)
 632		list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
 633	dma_desc->cb_count++;
 634
 635	sgreq->words_xferred = 0;
 636
 637	/* If not last req then put at end of pending list */
 638	if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) {
 639		list_move_tail(&sgreq->node, &tdc->pending_sg_req);
 640		sgreq->configured = false;
 641		st = handle_continuous_head_request(tdc, to_terminate);
 642		if (!st)
 643			dma_desc->dma_status = DMA_ERROR;
 644	}
 645}
 646
 647static void tegra_dma_tasklet(unsigned long data)
 648{
 649	struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
 650	struct dmaengine_desc_callback cb;
 651	struct tegra_dma_desc *dma_desc;
 652	unsigned int cb_count;
 653	unsigned long flags;
 
 654
 655	spin_lock_irqsave(&tdc->lock, flags);
 656	while (!list_empty(&tdc->cb_desc)) {
 657		dma_desc = list_first_entry(&tdc->cb_desc, typeof(*dma_desc),
 658					    cb_node);
 659		list_del(&dma_desc->cb_node);
 660		dmaengine_desc_get_callback(&dma_desc->txd, &cb);
 661		cb_count = dma_desc->cb_count;
 662		dma_desc->cb_count = 0;
 663		trace_tegra_dma_complete_cb(&tdc->dma_chan, cb_count,
 664					    cb.callback);
 665		spin_unlock_irqrestore(&tdc->lock, flags);
 666		while (cb_count--)
 667			dmaengine_desc_callback_invoke(&cb, NULL);
 668		spin_lock_irqsave(&tdc->lock, flags);
 669	}
 670	spin_unlock_irqrestore(&tdc->lock, flags);
 671}
 672
 673static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
 674{
 675	struct tegra_dma_channel *tdc = dev_id;
 676	u32 status;
 
 677
 678	spin_lock(&tdc->lock);
 679
 680	trace_tegra_dma_isr(&tdc->dma_chan, irq);
 681	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 682	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 683		tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 684		tdc->isr_handler(tdc, false);
 685		tasklet_schedule(&tdc->tasklet);
 686		wake_up_all(&tdc->wq);
 687		spin_unlock(&tdc->lock);
 688		return IRQ_HANDLED;
 689	}
 690
 691	spin_unlock(&tdc->lock);
 692	dev_info(tdc2dev(tdc), "Interrupt already served status 0x%08x\n",
 693		 status);
 694
 695	return IRQ_NONE;
 696}
 697
 698static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd)
 699{
 700	struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd);
 701	struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan);
 702	unsigned long flags;
 703	dma_cookie_t cookie;
 704
 705	spin_lock_irqsave(&tdc->lock, flags);
 706	dma_desc->dma_status = DMA_IN_PROGRESS;
 707	cookie = dma_cookie_assign(&dma_desc->txd);
 708	list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req);
 709	spin_unlock_irqrestore(&tdc->lock, flags);
 710
 711	return cookie;
 712}
 713
 714static void tegra_dma_issue_pending(struct dma_chan *dc)
 715{
 716	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 717	unsigned long flags;
 718	int err;
 719
 720	spin_lock_irqsave(&tdc->lock, flags);
 721	if (list_empty(&tdc->pending_sg_req)) {
 722		dev_err(tdc2dev(tdc), "No DMA request\n");
 723		goto end;
 724	}
 725	if (!tdc->busy) {
 726		err = pm_runtime_get_sync(tdc->tdma->dev);
 727		if (err < 0) {
 728			dev_err(tdc2dev(tdc), "Failed to enable DMA\n");
 729			goto end;
 730		}
 731
 732		tdc_start_head_req(tdc);
 733
 734		/* Continuous single mode: Configure next req */
 735		if (tdc->cyclic) {
 736			/*
 737			 * Wait for 1 burst time for configure DMA for
 738			 * next transfer.
 739			 */
 740			udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 741			tdc_configure_next_head_desc(tdc);
 742		}
 743	}
 744end:
 745	spin_unlock_irqrestore(&tdc->lock, flags);
 746}
 747
 748static int tegra_dma_terminate_all(struct dma_chan *dc)
 749{
 750	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 751	struct tegra_dma_desc *dma_desc;
 752	struct tegra_dma_sg_req *sgreq;
 
 753	unsigned long flags;
 754	u32 status, wcount;
 
 755	bool was_busy;
 756
 757	spin_lock_irqsave(&tdc->lock, flags);
 
 
 
 
 758
 759	if (!tdc->busy)
 760		goto skip_dma_stop;
 761
 762	/* Pause DMA before checking the queue status */
 763	tegra_dma_pause(tdc, true);
 764
 765	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 766	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 767		dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
 768		tdc->isr_handler(tdc, true);
 769		status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 770	}
 771	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 772		wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER);
 773	else
 774		wcount = status;
 775
 776	was_busy = tdc->busy;
 777	tegra_dma_stop(tdc);
 778
 779	if (!list_empty(&tdc->pending_sg_req) && was_busy) {
 780		sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq),
 781					 node);
 782		sgreq->dma_desc->bytes_transferred +=
 783				get_current_xferred_count(tdc, sgreq, wcount);
 784	}
 785	tegra_dma_resume(tdc);
 786
 787	pm_runtime_put(tdc->tdma->dev);
 788	wake_up_all(&tdc->wq);
 789
 790skip_dma_stop:
 791	tegra_dma_abort_all(tdc);
 792
 793	while (!list_empty(&tdc->cb_desc)) {
 794		dma_desc = list_first_entry(&tdc->cb_desc, typeof(*dma_desc),
 795					    cb_node);
 796		list_del(&dma_desc->cb_node);
 797		dma_desc->cb_count = 0;
 798	}
 799	spin_unlock_irqrestore(&tdc->lock, flags);
 800
 801	return 0;
 802}
 803
 804static bool tegra_dma_eoc_interrupt_deasserted(struct tegra_dma_channel *tdc)
 805{
 806	unsigned long flags;
 807	u32 status;
 808
 809	spin_lock_irqsave(&tdc->lock, flags);
 810	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 811	spin_unlock_irqrestore(&tdc->lock, flags);
 812
 813	return !(status & TEGRA_APBDMA_STATUS_ISE_EOC);
 814}
 815
 816static void tegra_dma_synchronize(struct dma_chan *dc)
 817{
 818	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 819	int err;
 820
 821	err = pm_runtime_get_sync(tdc->tdma->dev);
 822	if (err < 0) {
 823		dev_err(tdc2dev(tdc), "Failed to synchronize DMA: %d\n", err);
 824		return;
 825	}
 826
 827	/*
 828	 * CPU, which handles interrupt, could be busy in
 829	 * uninterruptible state, in this case sibling CPU
 830	 * should wait until interrupt is handled.
 831	 */
 832	wait_event(tdc->wq, tegra_dma_eoc_interrupt_deasserted(tdc));
 833
 834	tasklet_kill(&tdc->tasklet);
 835
 836	pm_runtime_put(tdc->tdma->dev);
 837}
 838
 839static unsigned int tegra_dma_sg_bytes_xferred(struct tegra_dma_channel *tdc,
 840					       struct tegra_dma_sg_req *sg_req)
 841{
 842	u32 status, wcount = 0;
 843
 844	if (!list_is_first(&sg_req->node, &tdc->pending_sg_req))
 845		return 0;
 846
 847	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 848		wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER);
 849
 850	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 851
 852	if (!tdc->tdma->chip_data->support_separate_wcount_reg)
 853		wcount = status;
 854
 855	if (status & TEGRA_APBDMA_STATUS_ISE_EOC)
 856		return sg_req->req_len;
 857
 858	wcount = get_current_xferred_count(tdc, sg_req, wcount);
 859
 860	if (!wcount) {
 861		/*
 862		 * If wcount wasn't ever polled for this SG before, then
 863		 * simply assume that transfer hasn't started yet.
 864		 *
 865		 * Otherwise it's the end of the transfer.
 866		 *
 867		 * The alternative would be to poll the status register
 868		 * until EOC bit is set or wcount goes UP. That's so
 869		 * because EOC bit is getting set only after the last
 870		 * burst's completion and counter is less than the actual
 871		 * transfer size by 4 bytes. The counter value wraps around
 872		 * in a cyclic mode before EOC is set(!), so we can't easily
 873		 * distinguish start of transfer from its end.
 874		 */
 875		if (sg_req->words_xferred)
 876			wcount = sg_req->req_len - 4;
 877
 878	} else if (wcount < sg_req->words_xferred) {
 879		/*
 880		 * This case will never happen for a non-cyclic transfer.
 881		 *
 882		 * For a cyclic transfer, although it is possible for the
 883		 * next transfer to have already started (resetting the word
 884		 * count), this case should still not happen because we should
 885		 * have detected that the EOC bit is set and hence the transfer
 886		 * was completed.
 887		 */
 888		WARN_ON_ONCE(1);
 889
 890		wcount = sg_req->req_len - 4;
 891	} else {
 892		sg_req->words_xferred = wcount;
 893	}
 894
 895	return wcount;
 896}
 897
 898static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
 899					   dma_cookie_t cookie,
 900					   struct dma_tx_state *txstate)
 901{
 902	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 903	struct tegra_dma_desc *dma_desc;
 904	struct tegra_dma_sg_req *sg_req;
 905	enum dma_status ret;
 906	unsigned long flags;
 907	unsigned int residual;
 908	unsigned int bytes = 0;
 909
 910	ret = dma_cookie_status(dc, cookie, txstate);
 911	if (ret == DMA_COMPLETE)
 912		return ret;
 913
 914	spin_lock_irqsave(&tdc->lock, flags);
 915
 916	/* Check on wait_ack desc status */
 917	list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
 918		if (dma_desc->txd.cookie == cookie) {
 919			ret = dma_desc->dma_status;
 920			goto found;
 921		}
 922	}
 923
 924	/* Check in pending list */
 925	list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
 926		dma_desc = sg_req->dma_desc;
 927		if (dma_desc->txd.cookie == cookie) {
 928			bytes = tegra_dma_sg_bytes_xferred(tdc, sg_req);
 929			ret = dma_desc->dma_status;
 930			goto found;
 931		}
 932	}
 933
 934	dev_dbg(tdc2dev(tdc), "cookie %d not found\n", cookie);
 935	dma_desc = NULL;
 936
 937found:
 938	if (dma_desc && txstate) {
 939		residual = dma_desc->bytes_requested -
 940			   ((dma_desc->bytes_transferred + bytes) %
 941			    dma_desc->bytes_requested);
 942		dma_set_residue(txstate, residual);
 943	}
 944
 945	trace_tegra_dma_tx_status(&tdc->dma_chan, cookie, txstate);
 946	spin_unlock_irqrestore(&tdc->lock, flags);
 947
 948	return ret;
 949}
 950
 951static inline unsigned int get_bus_width(struct tegra_dma_channel *tdc,
 952					 enum dma_slave_buswidth slave_bw)
 953{
 954	switch (slave_bw) {
 955	case DMA_SLAVE_BUSWIDTH_1_BYTE:
 956		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8;
 957	case DMA_SLAVE_BUSWIDTH_2_BYTES:
 958		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16;
 959	case DMA_SLAVE_BUSWIDTH_4_BYTES:
 960		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
 961	case DMA_SLAVE_BUSWIDTH_8_BYTES:
 962		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64;
 963	default:
 964		dev_warn(tdc2dev(tdc),
 965			 "slave bw is not supported, using 32bits\n");
 966		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
 967	}
 968}
 969
 970static inline unsigned int get_burst_size(struct tegra_dma_channel *tdc,
 971					  u32 burst_size,
 972					  enum dma_slave_buswidth slave_bw,
 973					  u32 len)
 974{
 975	unsigned int burst_byte, burst_ahb_width;
 
 976
 977	/*
 978	 * burst_size from client is in terms of the bus_width.
 979	 * convert them into AHB memory width which is 4 byte.
 980	 */
 981	burst_byte = burst_size * slave_bw;
 982	burst_ahb_width = burst_byte / 4;
 983
 984	/* If burst size is 0 then calculate the burst size based on length */
 985	if (!burst_ahb_width) {
 986		if (len & 0xF)
 987			return TEGRA_APBDMA_AHBSEQ_BURST_1;
 988		else if ((len >> 4) & 0x1)
 989			return TEGRA_APBDMA_AHBSEQ_BURST_4;
 990		else
 991			return TEGRA_APBDMA_AHBSEQ_BURST_8;
 992	}
 993	if (burst_ahb_width < 4)
 994		return TEGRA_APBDMA_AHBSEQ_BURST_1;
 995	else if (burst_ahb_width < 8)
 996		return TEGRA_APBDMA_AHBSEQ_BURST_4;
 997	else
 998		return TEGRA_APBDMA_AHBSEQ_BURST_8;
 999}
1000
1001static int get_transfer_param(struct tegra_dma_channel *tdc,
1002			      enum dma_transfer_direction direction,
1003			      u32 *apb_addr,
1004			      u32 *apb_seq,
1005			      u32 *csr,
1006			      unsigned int *burst_size,
1007			      enum dma_slave_buswidth *slave_bw)
1008{
1009	switch (direction) {
1010	case DMA_MEM_TO_DEV:
1011		*apb_addr = tdc->dma_sconfig.dst_addr;
1012		*apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width);
1013		*burst_size = tdc->dma_sconfig.dst_maxburst;
1014		*slave_bw = tdc->dma_sconfig.dst_addr_width;
1015		*csr = TEGRA_APBDMA_CSR_DIR;
1016		return 0;
1017
1018	case DMA_DEV_TO_MEM:
1019		*apb_addr = tdc->dma_sconfig.src_addr;
1020		*apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width);
1021		*burst_size = tdc->dma_sconfig.src_maxburst;
1022		*slave_bw = tdc->dma_sconfig.src_addr_width;
1023		*csr = 0;
1024		return 0;
1025
1026	default:
1027		dev_err(tdc2dev(tdc), "DMA direction is not supported\n");
1028		break;
1029	}
1030
1031	return -EINVAL;
1032}
1033
1034static void tegra_dma_prep_wcount(struct tegra_dma_channel *tdc,
1035				  struct tegra_dma_channel_regs *ch_regs,
1036				  u32 len)
1037{
1038	u32 len_field = (len - 4) & 0xFFFC;
1039
1040	if (tdc->tdma->chip_data->support_separate_wcount_reg)
1041		ch_regs->wcount = len_field;
1042	else
1043		ch_regs->csr |= len_field;
1044}
1045
1046static struct dma_async_tx_descriptor *
1047tegra_dma_prep_slave_sg(struct dma_chan *dc,
1048			struct scatterlist *sgl,
1049			unsigned int sg_len,
1050			enum dma_transfer_direction direction,
1051			unsigned long flags,
1052			void *context)
1053{
1054	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1055	struct tegra_dma_sg_req *sg_req = NULL;
1056	u32 csr, ahb_seq, apb_ptr, apb_seq;
1057	enum dma_slave_buswidth slave_bw;
1058	struct tegra_dma_desc *dma_desc;
1059	struct list_head req_list;
1060	struct scatterlist *sg;
1061	unsigned int burst_size;
1062	unsigned int i;
 
 
 
 
 
 
1063
1064	if (!tdc->config_init) {
1065		dev_err(tdc2dev(tdc), "DMA channel is not configured\n");
1066		return NULL;
1067	}
1068	if (sg_len < 1) {
1069		dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
1070		return NULL;
1071	}
1072
1073	if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
1074			       &burst_size, &slave_bw) < 0)
1075		return NULL;
1076
1077	INIT_LIST_HEAD(&req_list);
1078
1079	ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
1080	ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
1081					TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
1082	ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
1083
1084	csr |= TEGRA_APBDMA_CSR_ONCE;
1085
1086	if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) {
1087		csr |= TEGRA_APBDMA_CSR_FLOW;
1088		csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
1089	}
1090
1091	if (flags & DMA_PREP_INTERRUPT) {
1092		csr |= TEGRA_APBDMA_CSR_IE_EOC;
1093	} else {
1094		WARN_ON_ONCE(1);
1095		return NULL;
1096	}
1097
1098	apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
1099
1100	dma_desc = tegra_dma_desc_get(tdc);
1101	if (!dma_desc) {
1102		dev_err(tdc2dev(tdc), "DMA descriptors not available\n");
1103		return NULL;
1104	}
1105	INIT_LIST_HEAD(&dma_desc->tx_list);
1106	INIT_LIST_HEAD(&dma_desc->cb_node);
1107	dma_desc->cb_count = 0;
1108	dma_desc->bytes_requested = 0;
1109	dma_desc->bytes_transferred = 0;
1110	dma_desc->dma_status = DMA_IN_PROGRESS;
1111
1112	/* Make transfer requests */
1113	for_each_sg(sgl, sg, sg_len, i) {
1114		u32 len, mem;
1115
1116		mem = sg_dma_address(sg);
1117		len = sg_dma_len(sg);
1118
1119		if ((len & 3) || (mem & 3) ||
1120		    len > tdc->tdma->chip_data->max_dma_count) {
1121			dev_err(tdc2dev(tdc),
1122				"DMA length/memory address is not supported\n");
1123			tegra_dma_desc_put(tdc, dma_desc);
1124			return NULL;
1125		}
1126
1127		sg_req = tegra_dma_sg_req_get(tdc);
1128		if (!sg_req) {
1129			dev_err(tdc2dev(tdc), "DMA sg-req not available\n");
1130			tegra_dma_desc_put(tdc, dma_desc);
1131			return NULL;
1132		}
1133
1134		ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1135		dma_desc->bytes_requested += len;
1136
1137		sg_req->ch_regs.apb_ptr = apb_ptr;
1138		sg_req->ch_regs.ahb_ptr = mem;
1139		sg_req->ch_regs.csr = csr;
1140		tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1141		sg_req->ch_regs.apb_seq = apb_seq;
1142		sg_req->ch_regs.ahb_seq = ahb_seq;
1143		sg_req->configured = false;
1144		sg_req->last_sg = false;
1145		sg_req->dma_desc = dma_desc;
1146		sg_req->req_len = len;
1147
1148		list_add_tail(&sg_req->node, &dma_desc->tx_list);
1149	}
1150	sg_req->last_sg = true;
1151	if (flags & DMA_CTRL_ACK)
1152		dma_desc->txd.flags = DMA_CTRL_ACK;
1153
1154	/*
1155	 * Make sure that mode should not be conflicting with currently
1156	 * configured mode.
1157	 */
1158	if (!tdc->isr_handler) {
1159		tdc->isr_handler = handle_once_dma_done;
1160		tdc->cyclic = false;
1161	} else {
1162		if (tdc->cyclic) {
1163			dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n");
1164			tegra_dma_desc_put(tdc, dma_desc);
1165			return NULL;
1166		}
1167	}
1168
1169	return &dma_desc->txd;
1170}
1171
1172static struct dma_async_tx_descriptor *
1173tegra_dma_prep_dma_cyclic(struct dma_chan *dc, dma_addr_t buf_addr,
1174			  size_t buf_len,
1175			  size_t period_len,
1176			  enum dma_transfer_direction direction,
1177			  unsigned long flags)
1178{
1179	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 
1180	struct tegra_dma_sg_req *sg_req = NULL;
1181	u32 csr, ahb_seq, apb_ptr, apb_seq;
1182	enum dma_slave_buswidth slave_bw;
1183	struct tegra_dma_desc *dma_desc;
1184	dma_addr_t mem = buf_addr;
1185	unsigned int burst_size;
1186	size_t len, remain_len;
1187
1188	if (!buf_len || !period_len) {
1189		dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
1190		return NULL;
1191	}
1192
1193	if (!tdc->config_init) {
1194		dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
1195		return NULL;
1196	}
1197
1198	/*
1199	 * We allow to take more number of requests till DMA is
1200	 * not started. The driver will loop over all requests.
1201	 * Once DMA is started then new requests can be queued only after
1202	 * terminating the DMA.
1203	 */
1204	if (tdc->busy) {
1205		dev_err(tdc2dev(tdc), "Request not allowed when DMA running\n");
1206		return NULL;
1207	}
1208
1209	/*
1210	 * We only support cycle transfer when buf_len is multiple of
1211	 * period_len.
1212	 */
1213	if (buf_len % period_len) {
1214		dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
1215		return NULL;
1216	}
1217
1218	len = period_len;
1219	if ((len & 3) || (buf_addr & 3) ||
1220	    len > tdc->tdma->chip_data->max_dma_count) {
1221		dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
1222		return NULL;
1223	}
1224
1225	if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
1226			       &burst_size, &slave_bw) < 0)
1227		return NULL;
1228
1229	ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
1230	ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
1231					TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
1232	ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
1233
1234	if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) {
1235		csr |= TEGRA_APBDMA_CSR_FLOW;
1236		csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
1237	}
1238
1239	if (flags & DMA_PREP_INTERRUPT) {
1240		csr |= TEGRA_APBDMA_CSR_IE_EOC;
1241	} else {
1242		WARN_ON_ONCE(1);
1243		return NULL;
1244	}
1245
1246	apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
1247
1248	dma_desc = tegra_dma_desc_get(tdc);
1249	if (!dma_desc) {
1250		dev_err(tdc2dev(tdc), "not enough descriptors available\n");
1251		return NULL;
1252	}
1253
1254	INIT_LIST_HEAD(&dma_desc->tx_list);
1255	INIT_LIST_HEAD(&dma_desc->cb_node);
1256	dma_desc->cb_count = 0;
1257
1258	dma_desc->bytes_transferred = 0;
1259	dma_desc->bytes_requested = buf_len;
1260	remain_len = buf_len;
1261
1262	/* Split transfer equal to period size */
1263	while (remain_len) {
1264		sg_req = tegra_dma_sg_req_get(tdc);
1265		if (!sg_req) {
1266			dev_err(tdc2dev(tdc), "DMA sg-req not available\n");
1267			tegra_dma_desc_put(tdc, dma_desc);
1268			return NULL;
1269		}
1270
1271		ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1272		sg_req->ch_regs.apb_ptr = apb_ptr;
1273		sg_req->ch_regs.ahb_ptr = mem;
1274		sg_req->ch_regs.csr = csr;
1275		tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1276		sg_req->ch_regs.apb_seq = apb_seq;
1277		sg_req->ch_regs.ahb_seq = ahb_seq;
1278		sg_req->configured = false;
1279		sg_req->last_sg = false;
1280		sg_req->dma_desc = dma_desc;
1281		sg_req->req_len = len;
1282
1283		list_add_tail(&sg_req->node, &dma_desc->tx_list);
1284		remain_len -= len;
1285		mem += len;
1286	}
1287	sg_req->last_sg = true;
1288	if (flags & DMA_CTRL_ACK)
1289		dma_desc->txd.flags = DMA_CTRL_ACK;
1290
1291	/*
1292	 * Make sure that mode should not be conflicting with currently
1293	 * configured mode.
1294	 */
1295	if (!tdc->isr_handler) {
1296		tdc->isr_handler = handle_cont_sngl_cycle_dma_done;
1297		tdc->cyclic = true;
1298	} else {
1299		if (!tdc->cyclic) {
1300			dev_err(tdc2dev(tdc), "DMA configuration conflict\n");
1301			tegra_dma_desc_put(tdc, dma_desc);
1302			return NULL;
1303		}
1304	}
1305
1306	return &dma_desc->txd;
1307}
1308
1309static int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
1310{
1311	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 
 
1312
1313	dma_cookie_init(&tdc->dma_chan);
 
 
 
 
 
1314
1315	return 0;
1316}
1317
1318static void tegra_dma_free_chan_resources(struct dma_chan *dc)
1319{
1320	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 
1321	struct tegra_dma_desc *dma_desc;
1322	struct tegra_dma_sg_req *sg_req;
1323	struct list_head dma_desc_list;
1324	struct list_head sg_req_list;
 
1325
1326	INIT_LIST_HEAD(&dma_desc_list);
1327	INIT_LIST_HEAD(&sg_req_list);
1328
1329	dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
1330
1331	tegra_dma_terminate_all(dc);
1332	tasklet_kill(&tdc->tasklet);
1333
 
1334	list_splice_init(&tdc->pending_sg_req, &sg_req_list);
1335	list_splice_init(&tdc->free_sg_req, &sg_req_list);
1336	list_splice_init(&tdc->free_dma_desc, &dma_desc_list);
1337	INIT_LIST_HEAD(&tdc->cb_desc);
1338	tdc->config_init = false;
1339	tdc->isr_handler = NULL;
 
1340
1341	while (!list_empty(&dma_desc_list)) {
1342		dma_desc = list_first_entry(&dma_desc_list, typeof(*dma_desc),
1343					    node);
1344		list_del(&dma_desc->node);
1345		kfree(dma_desc);
1346	}
1347
1348	while (!list_empty(&sg_req_list)) {
1349		sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node);
1350		list_del(&sg_req->node);
1351		kfree(sg_req);
1352	}
 
1353
1354	tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1355}
1356
1357static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
1358					   struct of_dma *ofdma)
1359{
1360	struct tegra_dma *tdma = ofdma->of_dma_data;
1361	struct tegra_dma_channel *tdc;
1362	struct dma_chan *chan;
 
1363
1364	if (dma_spec->args[0] > TEGRA_APBDMA_CSR_REQ_SEL_MASK) {
1365		dev_err(tdma->dev, "Invalid slave id: %d\n", dma_spec->args[0]);
1366		return NULL;
1367	}
1368
1369	chan = dma_get_any_slave_channel(&tdma->dma_dev);
1370	if (!chan)
1371		return NULL;
1372
1373	tdc = to_tegra_dma_chan(chan);
1374	tdc->slave_id = dma_spec->args[0];
1375
1376	return chan;
1377}
1378
1379/* Tegra20 specific DMA controller information */
1380static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
1381	.nr_channels		= 16,
1382	.channel_reg_size	= 0x20,
1383	.max_dma_count		= 1024UL * 64,
1384	.support_channel_pause	= false,
1385	.support_separate_wcount_reg = false,
1386};
1387
1388/* Tegra30 specific DMA controller information */
1389static const struct tegra_dma_chip_data tegra30_dma_chip_data = {
1390	.nr_channels		= 32,
1391	.channel_reg_size	= 0x20,
1392	.max_dma_count		= 1024UL * 64,
1393	.support_channel_pause	= false,
1394	.support_separate_wcount_reg = false,
1395};
1396
1397/* Tegra114 specific DMA controller information */
1398static const struct tegra_dma_chip_data tegra114_dma_chip_data = {
1399	.nr_channels		= 32,
1400	.channel_reg_size	= 0x20,
1401	.max_dma_count		= 1024UL * 64,
1402	.support_channel_pause	= true,
1403	.support_separate_wcount_reg = false,
1404};
1405
1406/* Tegra148 specific DMA controller information */
1407static const struct tegra_dma_chip_data tegra148_dma_chip_data = {
1408	.nr_channels		= 32,
1409	.channel_reg_size	= 0x40,
1410	.max_dma_count		= 1024UL * 64,
1411	.support_channel_pause	= true,
1412	.support_separate_wcount_reg = true,
1413};
1414
1415static int tegra_dma_init_hw(struct tegra_dma *tdma)
1416{
1417	int err;
1418
1419	err = reset_control_assert(tdma->rst);
1420	if (err) {
1421		dev_err(tdma->dev, "failed to assert reset: %d\n", err);
1422		return err;
1423	}
1424
1425	err = clk_enable(tdma->dma_clk);
1426	if (err) {
1427		dev_err(tdma->dev, "failed to enable clk: %d\n", err);
1428		return err;
1429	}
1430
1431	/* reset DMA controller */
1432	udelay(2);
1433	reset_control_deassert(tdma->rst);
1434
1435	/* enable global DMA registers */
1436	tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE);
1437	tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1438	tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFF);
1439
1440	clk_disable(tdma->dma_clk);
1441
1442	return 0;
1443}
1444
1445static int tegra_dma_probe(struct platform_device *pdev)
1446{
1447	const struct tegra_dma_chip_data *cdata;
1448	struct tegra_dma *tdma;
1449	unsigned int i;
1450	size_t size;
1451	int ret;
 
 
1452
1453	cdata = of_device_get_match_data(&pdev->dev);
1454	size = struct_size(tdma, channels, cdata->nr_channels);
 
 
 
1455
1456	tdma = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
 
1457	if (!tdma)
1458		return -ENOMEM;
1459
1460	tdma->dev = &pdev->dev;
1461	tdma->chip_data = cdata;
1462	platform_set_drvdata(pdev, tdma);
1463
1464	tdma->base_addr = devm_platform_ioremap_resource(pdev, 0);
 
1465	if (IS_ERR(tdma->base_addr))
1466		return PTR_ERR(tdma->base_addr);
1467
1468	tdma->dma_clk = devm_clk_get(&pdev->dev, NULL);
1469	if (IS_ERR(tdma->dma_clk)) {
1470		dev_err(&pdev->dev, "Error: Missing controller clock\n");
1471		return PTR_ERR(tdma->dma_clk);
1472	}
1473
1474	tdma->rst = devm_reset_control_get(&pdev->dev, "dma");
1475	if (IS_ERR(tdma->rst)) {
1476		dev_err(&pdev->dev, "Error: Missing reset\n");
1477		return PTR_ERR(tdma->rst);
1478	}
1479
1480	spin_lock_init(&tdma->global_lock);
1481
1482	ret = clk_prepare(tdma->dma_clk);
1483	if (ret)
 
 
 
 
 
 
1484		return ret;
 
1485
1486	ret = tegra_dma_init_hw(tdma);
1487	if (ret)
1488		goto err_clk_unprepare;
 
1489
1490	pm_runtime_irq_safe(&pdev->dev);
1491	pm_runtime_enable(&pdev->dev);
 
 
 
 
1492
1493	INIT_LIST_HEAD(&tdma->dma_dev.channels);
1494	for (i = 0; i < cdata->nr_channels; i++) {
1495		struct tegra_dma_channel *tdc = &tdma->channels[i];
1496		int irq;
1497
1498		tdc->chan_addr = tdma->base_addr +
1499				 TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET +
1500				 (i * cdata->channel_reg_size);
1501
1502		irq = platform_get_irq(pdev, i);
1503		if (irq < 0) {
1504			ret = irq;
1505			goto err_pm_disable;
 
1506		}
1507
1508		snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i);
1509		ret = devm_request_irq(&pdev->dev, irq, tegra_dma_isr, 0,
1510				       tdc->name, tdc);
1511		if (ret) {
1512			dev_err(&pdev->dev,
1513				"request_irq failed with err %d channel %d\n",
1514				ret, i);
1515			goto err_pm_disable;
1516		}
1517
1518		tdc->dma_chan.device = &tdma->dma_dev;
1519		dma_cookie_init(&tdc->dma_chan);
1520		list_add_tail(&tdc->dma_chan.device_node,
1521			      &tdma->dma_dev.channels);
1522		tdc->tdma = tdma;
1523		tdc->id = i;
1524		tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1525
1526		tasklet_init(&tdc->tasklet, tegra_dma_tasklet,
1527			     (unsigned long)tdc);
1528		spin_lock_init(&tdc->lock);
1529		init_waitqueue_head(&tdc->wq);
1530
1531		INIT_LIST_HEAD(&tdc->pending_sg_req);
1532		INIT_LIST_HEAD(&tdc->free_sg_req);
1533		INIT_LIST_HEAD(&tdc->free_dma_desc);
1534		INIT_LIST_HEAD(&tdc->cb_desc);
1535	}
1536
1537	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
1538	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
1539	dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
1540
1541	tdma->global_pause_count = 0;
1542	tdma->dma_dev.dev = &pdev->dev;
1543	tdma->dma_dev.device_alloc_chan_resources =
1544					tegra_dma_alloc_chan_resources;
1545	tdma->dma_dev.device_free_chan_resources =
1546					tegra_dma_free_chan_resources;
1547	tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg;
1548	tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic;
1549	tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1550		BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1551		BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1552		BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1553	tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1554		BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1555		BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1556		BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1557	tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1558	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 
 
 
 
 
1559	tdma->dma_dev.device_config = tegra_dma_slave_config;
1560	tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
1561	tdma->dma_dev.device_synchronize = tegra_dma_synchronize;
1562	tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
1563	tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
1564
1565	ret = dma_async_device_register(&tdma->dma_dev);
1566	if (ret < 0) {
1567		dev_err(&pdev->dev,
1568			"Tegra20 APB DMA driver registration failed %d\n", ret);
1569		goto err_pm_disable;
1570	}
1571
1572	ret = of_dma_controller_register(pdev->dev.of_node,
1573					 tegra_dma_of_xlate, tdma);
1574	if (ret < 0) {
1575		dev_err(&pdev->dev,
1576			"Tegra20 APB DMA OF registration failed %d\n", ret);
1577		goto err_unregister_dma_dev;
1578	}
1579
1580	dev_info(&pdev->dev, "Tegra20 APB DMA driver registered %u channels\n",
1581		 cdata->nr_channels);
1582
1583	return 0;
1584
1585err_unregister_dma_dev:
1586	dma_async_device_unregister(&tdma->dma_dev);
 
 
 
1587
1588err_pm_disable:
1589	pm_runtime_disable(&pdev->dev);
1590
1591err_clk_unprepare:
1592	clk_unprepare(tdma->dma_clk);
1593
 
 
 
1594	return ret;
1595}
1596
1597static int tegra_dma_remove(struct platform_device *pdev)
1598{
1599	struct tegra_dma *tdma = platform_get_drvdata(pdev);
 
 
1600
1601	of_dma_controller_free(pdev->dev.of_node);
1602	dma_async_device_unregister(&tdma->dma_dev);
 
 
 
 
 
 
 
1603	pm_runtime_disable(&pdev->dev);
1604	clk_unprepare(tdma->dma_clk);
 
1605
1606	return 0;
1607}
1608
1609static int __maybe_unused tegra_dma_runtime_suspend(struct device *dev)
1610{
1611	struct tegra_dma *tdma = dev_get_drvdata(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1612
1613	clk_disable(tdma->dma_clk);
1614
1615	return 0;
1616}
1617
1618static int __maybe_unused tegra_dma_runtime_resume(struct device *dev)
1619{
1620	struct tegra_dma *tdma = dev_get_drvdata(dev);
 
1621
1622	return clk_enable(tdma->dma_clk);
1623}
 
 
 
1624
1625static int __maybe_unused tegra_dma_dev_suspend(struct device *dev)
1626{
1627	struct tegra_dma *tdma = dev_get_drvdata(dev);
1628	unsigned long flags;
1629	unsigned int i;
1630	bool busy;
1631
1632	for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1633		struct tegra_dma_channel *tdc = &tdma->channels[i];
 
1634
1635		tasklet_kill(&tdc->tasklet);
1636
1637		spin_lock_irqsave(&tdc->lock, flags);
1638		busy = tdc->busy;
1639		spin_unlock_irqrestore(&tdc->lock, flags);
1640
1641		if (busy) {
1642			dev_err(tdma->dev, "channel %u busy\n", i);
1643			return -EBUSY;
1644		}
 
 
 
1645	}
1646
1647	return pm_runtime_force_suspend(dev);
1648}
1649
1650static int __maybe_unused tegra_dma_dev_resume(struct device *dev)
1651{
1652	struct tegra_dma *tdma = dev_get_drvdata(dev);
1653	int err;
1654
1655	err = tegra_dma_init_hw(tdma);
1656	if (err)
1657		return err;
1658
1659	return pm_runtime_force_resume(dev);
1660}
1661
1662static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
1663	SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume,
1664			   NULL)
1665	SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_dev_suspend, tegra_dma_dev_resume)
 
1666};
1667
1668static const struct of_device_id tegra_dma_of_match[] = {
1669	{
1670		.compatible = "nvidia,tegra148-apbdma",
1671		.data = &tegra148_dma_chip_data,
1672	}, {
1673		.compatible = "nvidia,tegra114-apbdma",
1674		.data = &tegra114_dma_chip_data,
1675	}, {
1676		.compatible = "nvidia,tegra30-apbdma",
1677		.data = &tegra30_dma_chip_data,
1678	}, {
1679		.compatible = "nvidia,tegra20-apbdma",
1680		.data = &tegra20_dma_chip_data,
1681	}, {
1682	},
1683};
1684MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
1685
1686static struct platform_driver tegra_dmac_driver = {
1687	.driver = {
1688		.name	= "tegra-apbdma",
1689		.pm	= &tegra_dma_dev_pm_ops,
1690		.of_match_table = tegra_dma_of_match,
1691	},
1692	.probe		= tegra_dma_probe,
1693	.remove		= tegra_dma_remove,
1694};
1695
1696module_platform_driver(tegra_dmac_driver);
1697
 
1698MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver");
1699MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
1700MODULE_LICENSE("GPL v2");
v4.17
 
   1/*
   2 * DMA driver for Nvidia's Tegra20 APB DMA controller.
   3 *
   4 * Copyright (c) 2012-2013, NVIDIA CORPORATION.  All rights reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms and conditions of the GNU General Public License,
   8 * version 2, as published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope it will be useful, but WITHOUT
  11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13 * more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19#include <linux/bitops.h>
  20#include <linux/clk.h>
  21#include <linux/delay.h>
  22#include <linux/dmaengine.h>
  23#include <linux/dma-mapping.h>
  24#include <linux/err.h>
  25#include <linux/init.h>
  26#include <linux/interrupt.h>
  27#include <linux/io.h>
  28#include <linux/mm.h>
  29#include <linux/module.h>
  30#include <linux/of.h>
  31#include <linux/of_device.h>
  32#include <linux/of_dma.h>
  33#include <linux/platform_device.h>
  34#include <linux/pm.h>
  35#include <linux/pm_runtime.h>
  36#include <linux/reset.h>
  37#include <linux/slab.h>
 
  38
  39#include "dmaengine.h"
  40
 
 
 
  41#define TEGRA_APBDMA_GENERAL			0x0
  42#define TEGRA_APBDMA_GENERAL_ENABLE		BIT(31)
  43
  44#define TEGRA_APBDMA_CONTROL			0x010
  45#define TEGRA_APBDMA_IRQ_MASK			0x01c
  46#define TEGRA_APBDMA_IRQ_MASK_SET		0x020
  47
  48/* CSR register */
  49#define TEGRA_APBDMA_CHAN_CSR			0x00
  50#define TEGRA_APBDMA_CSR_ENB			BIT(31)
  51#define TEGRA_APBDMA_CSR_IE_EOC			BIT(30)
  52#define TEGRA_APBDMA_CSR_HOLD			BIT(29)
  53#define TEGRA_APBDMA_CSR_DIR			BIT(28)
  54#define TEGRA_APBDMA_CSR_ONCE			BIT(27)
  55#define TEGRA_APBDMA_CSR_FLOW			BIT(21)
  56#define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT		16
  57#define TEGRA_APBDMA_CSR_REQ_SEL_MASK		0x1F
  58#define TEGRA_APBDMA_CSR_WCOUNT_MASK		0xFFFC
  59
  60/* STATUS register */
  61#define TEGRA_APBDMA_CHAN_STATUS		0x004
  62#define TEGRA_APBDMA_STATUS_BUSY		BIT(31)
  63#define TEGRA_APBDMA_STATUS_ISE_EOC		BIT(30)
  64#define TEGRA_APBDMA_STATUS_HALT		BIT(29)
  65#define TEGRA_APBDMA_STATUS_PING_PONG		BIT(28)
  66#define TEGRA_APBDMA_STATUS_COUNT_SHIFT		2
  67#define TEGRA_APBDMA_STATUS_COUNT_MASK		0xFFFC
  68
  69#define TEGRA_APBDMA_CHAN_CSRE			0x00C
  70#define TEGRA_APBDMA_CHAN_CSRE_PAUSE		(1 << 31)
  71
  72/* AHB memory address */
  73#define TEGRA_APBDMA_CHAN_AHBPTR		0x010
  74
  75/* AHB sequence register */
  76#define TEGRA_APBDMA_CHAN_AHBSEQ		0x14
  77#define TEGRA_APBDMA_AHBSEQ_INTR_ENB		BIT(31)
  78#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8		(0 << 28)
  79#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16	(1 << 28)
  80#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32	(2 << 28)
  81#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64	(3 << 28)
  82#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128	(4 << 28)
  83#define TEGRA_APBDMA_AHBSEQ_DATA_SWAP		BIT(27)
  84#define TEGRA_APBDMA_AHBSEQ_BURST_1		(4 << 24)
  85#define TEGRA_APBDMA_AHBSEQ_BURST_4		(5 << 24)
  86#define TEGRA_APBDMA_AHBSEQ_BURST_8		(6 << 24)
  87#define TEGRA_APBDMA_AHBSEQ_DBL_BUF		BIT(19)
  88#define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT		16
  89#define TEGRA_APBDMA_AHBSEQ_WRAP_NONE		0
  90
  91/* APB address */
  92#define TEGRA_APBDMA_CHAN_APBPTR		0x018
  93
  94/* APB sequence register */
  95#define TEGRA_APBDMA_CHAN_APBSEQ		0x01c
  96#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8		(0 << 28)
  97#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16	(1 << 28)
  98#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32	(2 << 28)
  99#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64	(3 << 28)
 100#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128	(4 << 28)
 101#define TEGRA_APBDMA_APBSEQ_DATA_SWAP		BIT(27)
 102#define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1		(1 << 16)
 103
 104/* Tegra148 specific registers */
 105#define TEGRA_APBDMA_CHAN_WCOUNT		0x20
 106
 107#define TEGRA_APBDMA_CHAN_WORD_TRANSFER		0x24
 108
 109/*
 110 * If any burst is in flight and DMA paused then this is the time to complete
 111 * on-flight burst and update DMA status register.
 112 */
 113#define TEGRA_APBDMA_BURST_COMPLETE_TIME	20
 114
 115/* Channel base address offset from APBDMA base address */
 116#define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET	0x1000
 117
 118#define TEGRA_APBDMA_SLAVE_ID_INVALID	(TEGRA_APBDMA_CSR_REQ_SEL_MASK + 1)
 119
 120struct tegra_dma;
 121
 122/*
 123 * tegra_dma_chip_data Tegra chip specific DMA data
 124 * @nr_channels: Number of channels available in the controller.
 125 * @channel_reg_size: Channel register size/stride.
 126 * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
 127 * @support_channel_pause: Support channel wise pause of dma.
 128 * @support_separate_wcount_reg: Support separate word count register.
 129 */
 130struct tegra_dma_chip_data {
 131	int nr_channels;
 132	int channel_reg_size;
 133	int max_dma_count;
 134	bool support_channel_pause;
 135	bool support_separate_wcount_reg;
 136};
 137
 138/* DMA channel registers */
 139struct tegra_dma_channel_regs {
 140	unsigned long	csr;
 141	unsigned long	ahb_ptr;
 142	unsigned long	apb_ptr;
 143	unsigned long	ahb_seq;
 144	unsigned long	apb_seq;
 145	unsigned long	wcount;
 146};
 147
 148/*
 149 * tegra_dma_sg_req: Dma request details to configure hardware. This
 150 * contains the details for one transfer to configure DMA hw.
 151 * The client's request for data transfer can be broken into multiple
 152 * sub-transfer as per requester details and hw support.
 153 * This sub transfer get added in the list of transfer and point to Tegra
 154 * DMA descriptor which manages the transfer details.
 155 */
 156struct tegra_dma_sg_req {
 157	struct tegra_dma_channel_regs	ch_regs;
 158	int				req_len;
 159	bool				configured;
 160	bool				last_sg;
 161	struct list_head		node;
 162	struct tegra_dma_desc		*dma_desc;
 
 163};
 164
 165/*
 166 * tegra_dma_desc: Tegra DMA descriptors which manages the client requests.
 167 * This descriptor keep track of transfer status, callbacks and request
 168 * counts etc.
 169 */
 170struct tegra_dma_desc {
 171	struct dma_async_tx_descriptor	txd;
 172	int				bytes_requested;
 173	int				bytes_transferred;
 174	enum dma_status			dma_status;
 175	struct list_head		node;
 176	struct list_head		tx_list;
 177	struct list_head		cb_node;
 178	int				cb_count;
 179};
 180
 181struct tegra_dma_channel;
 182
 183typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc,
 184				bool to_terminate);
 185
 186/* tegra_dma_channel: Channel specific information */
 187struct tegra_dma_channel {
 188	struct dma_chan		dma_chan;
 189	char			name[30];
 190	bool			config_init;
 191	int			id;
 192	int			irq;
 193	void __iomem		*chan_addr;
 194	spinlock_t		lock;
 195	bool			busy;
 196	struct tegra_dma	*tdma;
 197	bool			cyclic;
 198
 199	/* Different lists for managing the requests */
 200	struct list_head	free_sg_req;
 201	struct list_head	pending_sg_req;
 202	struct list_head	free_dma_desc;
 203	struct list_head	cb_desc;
 204
 205	/* ISR handler and tasklet for bottom half of isr handling */
 206	dma_isr_handler		isr_handler;
 207	struct tasklet_struct	tasklet;
 208
 209	/* Channel-slave specific configuration */
 210	unsigned int slave_id;
 211	struct dma_slave_config dma_sconfig;
 212	struct tegra_dma_channel_regs	channel_reg;
 
 
 213};
 214
 215/* tegra_dma: Tegra DMA specific information */
 216struct tegra_dma {
 217	struct dma_device		dma_dev;
 218	struct device			*dev;
 219	struct clk			*dma_clk;
 220	struct reset_control		*rst;
 221	spinlock_t			global_lock;
 222	void __iomem			*base_addr;
 223	const struct tegra_dma_chip_data *chip_data;
 224
 225	/*
 226	 * Counter for managing global pausing of the DMA controller.
 227	 * Only applicable for devices that don't support individual
 228	 * channel pausing.
 229	 */
 230	u32				global_pause_count;
 231
 232	/* Some register need to be cache before suspend */
 233	u32				reg_gen;
 234
 235	/* Last member of the structure */
 236	struct tegra_dma_channel channels[0];
 237};
 238
 239static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
 240{
 241	writel(val, tdma->base_addr + reg);
 242}
 243
 244static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
 245{
 246	return readl(tdma->base_addr + reg);
 247}
 248
 249static inline void tdc_write(struct tegra_dma_channel *tdc,
 250		u32 reg, u32 val)
 251{
 252	writel(val, tdc->chan_addr + reg);
 253}
 254
 255static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
 256{
 257	return readl(tdc->chan_addr + reg);
 258}
 259
 260static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc)
 261{
 262	return container_of(dc, struct tegra_dma_channel, dma_chan);
 263}
 264
 265static inline struct tegra_dma_desc *txd_to_tegra_dma_desc(
 266		struct dma_async_tx_descriptor *td)
 267{
 268	return container_of(td, struct tegra_dma_desc, txd);
 269}
 270
 271static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
 272{
 273	return &tdc->dma_chan.dev->device;
 274}
 275
 276static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx);
 277static int tegra_dma_runtime_suspend(struct device *dev);
 278static int tegra_dma_runtime_resume(struct device *dev);
 279
 280/* Get DMA desc from free list, if not there then allocate it.  */
 281static struct tegra_dma_desc *tegra_dma_desc_get(
 282		struct tegra_dma_channel *tdc)
 283{
 284	struct tegra_dma_desc *dma_desc;
 285	unsigned long flags;
 286
 287	spin_lock_irqsave(&tdc->lock, flags);
 288
 289	/* Do not allocate if desc are waiting for ack */
 290	list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
 291		if (async_tx_test_ack(&dma_desc->txd)) {
 292			list_del(&dma_desc->node);
 293			spin_unlock_irqrestore(&tdc->lock, flags);
 294			dma_desc->txd.flags = 0;
 295			return dma_desc;
 296		}
 297	}
 298
 299	spin_unlock_irqrestore(&tdc->lock, flags);
 300
 301	/* Allocate DMA desc */
 302	dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT);
 303	if (!dma_desc)
 304		return NULL;
 305
 306	dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan);
 307	dma_desc->txd.tx_submit = tegra_dma_tx_submit;
 308	dma_desc->txd.flags = 0;
 
 309	return dma_desc;
 310}
 311
 312static void tegra_dma_desc_put(struct tegra_dma_channel *tdc,
 313		struct tegra_dma_desc *dma_desc)
 314{
 315	unsigned long flags;
 316
 317	spin_lock_irqsave(&tdc->lock, flags);
 318	if (!list_empty(&dma_desc->tx_list))
 319		list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req);
 320	list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 321	spin_unlock_irqrestore(&tdc->lock, flags);
 322}
 323
 324static struct tegra_dma_sg_req *tegra_dma_sg_req_get(
 325		struct tegra_dma_channel *tdc)
 326{
 327	struct tegra_dma_sg_req *sg_req = NULL;
 328	unsigned long flags;
 329
 330	spin_lock_irqsave(&tdc->lock, flags);
 331	if (!list_empty(&tdc->free_sg_req)) {
 332		sg_req = list_first_entry(&tdc->free_sg_req,
 333					typeof(*sg_req), node);
 334		list_del(&sg_req->node);
 335		spin_unlock_irqrestore(&tdc->lock, flags);
 336		return sg_req;
 337	}
 338	spin_unlock_irqrestore(&tdc->lock, flags);
 339
 340	sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_NOWAIT);
 341
 342	return sg_req;
 343}
 344
 345static int tegra_dma_slave_config(struct dma_chan *dc,
 346		struct dma_slave_config *sconfig)
 347{
 348	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 349
 350	if (!list_empty(&tdc->pending_sg_req)) {
 351		dev_err(tdc2dev(tdc), "Configuration not allowed\n");
 352		return -EBUSY;
 353	}
 354
 355	memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
 356	if (tdc->slave_id == TEGRA_APBDMA_SLAVE_ID_INVALID &&
 357	    sconfig->device_fc) {
 358		if (sconfig->slave_id > TEGRA_APBDMA_CSR_REQ_SEL_MASK)
 359			return -EINVAL;
 360		tdc->slave_id = sconfig->slave_id;
 361	}
 362	tdc->config_init = true;
 
 363	return 0;
 364}
 365
 366static void tegra_dma_global_pause(struct tegra_dma_channel *tdc,
 367	bool wait_for_burst_complete)
 368{
 369	struct tegra_dma *tdma = tdc->tdma;
 370
 371	spin_lock(&tdma->global_lock);
 372
 373	if (tdc->tdma->global_pause_count == 0) {
 374		tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0);
 375		if (wait_for_burst_complete)
 376			udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 377	}
 378
 379	tdc->tdma->global_pause_count++;
 380
 381	spin_unlock(&tdma->global_lock);
 382}
 383
 384static void tegra_dma_global_resume(struct tegra_dma_channel *tdc)
 385{
 386	struct tegra_dma *tdma = tdc->tdma;
 387
 388	spin_lock(&tdma->global_lock);
 389
 390	if (WARN_ON(tdc->tdma->global_pause_count == 0))
 391		goto out;
 392
 393	if (--tdc->tdma->global_pause_count == 0)
 394		tdma_write(tdma, TEGRA_APBDMA_GENERAL,
 395			   TEGRA_APBDMA_GENERAL_ENABLE);
 396
 397out:
 398	spin_unlock(&tdma->global_lock);
 399}
 400
 401static void tegra_dma_pause(struct tegra_dma_channel *tdc,
 402	bool wait_for_burst_complete)
 403{
 404	struct tegra_dma *tdma = tdc->tdma;
 405
 406	if (tdma->chip_data->support_channel_pause) {
 407		tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE,
 408				TEGRA_APBDMA_CHAN_CSRE_PAUSE);
 409		if (wait_for_burst_complete)
 410			udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 411	} else {
 412		tegra_dma_global_pause(tdc, wait_for_burst_complete);
 413	}
 414}
 415
 416static void tegra_dma_resume(struct tegra_dma_channel *tdc)
 417{
 418	struct tegra_dma *tdma = tdc->tdma;
 419
 420	if (tdma->chip_data->support_channel_pause) {
 421		tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0);
 422	} else {
 423		tegra_dma_global_resume(tdc);
 424	}
 425}
 426
 427static void tegra_dma_stop(struct tegra_dma_channel *tdc)
 428{
 429	u32 csr;
 430	u32 status;
 431
 432	/* Disable interrupts */
 433	csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
 434	csr &= ~TEGRA_APBDMA_CSR_IE_EOC;
 435	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
 436
 437	/* Disable DMA */
 438	csr &= ~TEGRA_APBDMA_CSR_ENB;
 439	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
 440
 441	/* Clear interrupt status if it is there */
 442	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 443	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 444		dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
 445		tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 446	}
 447	tdc->busy = false;
 448}
 449
 450static void tegra_dma_start(struct tegra_dma_channel *tdc,
 451		struct tegra_dma_sg_req *sg_req)
 452{
 453	struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs;
 454
 455	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr);
 456	tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq);
 457	tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr);
 458	tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq);
 459	tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr);
 460	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 461		tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_regs->wcount);
 462
 463	/* Start DMA */
 464	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
 465				ch_regs->csr | TEGRA_APBDMA_CSR_ENB);
 466}
 467
 468static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc,
 469		struct tegra_dma_sg_req *nsg_req)
 470{
 471	unsigned long status;
 472
 473	/*
 474	 * The DMA controller reloads the new configuration for next transfer
 475	 * after last burst of current transfer completes.
 476	 * If there is no IEC status then this makes sure that last burst
 477	 * has not be completed. There may be case that last burst is on
 478	 * flight and so it can complete but because DMA is paused, it
 479	 * will not generates interrupt as well as not reload the new
 480	 * configuration.
 481	 * If there is already IEC status then interrupt handler need to
 482	 * load new configuration.
 483	 */
 484	tegra_dma_pause(tdc, false);
 485	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 486
 487	/*
 488	 * If interrupt is pending then do nothing as the ISR will handle
 489	 * the programing for new request.
 490	 */
 491	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 492		dev_err(tdc2dev(tdc),
 493			"Skipping new configuration as interrupt is pending\n");
 494		tegra_dma_resume(tdc);
 495		return;
 496	}
 497
 498	/* Safe to program new configuration */
 499	tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr);
 500	tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr);
 501	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 502		tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
 503						nsg_req->ch_regs.wcount);
 504	tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
 505				nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB);
 506	nsg_req->configured = true;
 
 507
 508	tegra_dma_resume(tdc);
 509}
 510
 511static void tdc_start_head_req(struct tegra_dma_channel *tdc)
 512{
 513	struct tegra_dma_sg_req *sg_req;
 514
 515	if (list_empty(&tdc->pending_sg_req))
 516		return;
 517
 518	sg_req = list_first_entry(&tdc->pending_sg_req,
 519					typeof(*sg_req), node);
 520	tegra_dma_start(tdc, sg_req);
 521	sg_req->configured = true;
 
 522	tdc->busy = true;
 523}
 524
 525static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
 526{
 527	struct tegra_dma_sg_req *hsgreq;
 528	struct tegra_dma_sg_req *hnsgreq;
 529
 530	if (list_empty(&tdc->pending_sg_req))
 531		return;
 532
 533	hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
 534	if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) {
 535		hnsgreq = list_first_entry(&hsgreq->node,
 536					typeof(*hnsgreq), node);
 537		tegra_dma_configure_for_next(tdc, hnsgreq);
 538	}
 539}
 540
 541static inline int get_current_xferred_count(struct tegra_dma_channel *tdc,
 542	struct tegra_dma_sg_req *sg_req, unsigned long status)
 
 
 543{
 544	return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4;
 545}
 546
 547static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
 548{
 
 549	struct tegra_dma_sg_req *sgreq;
 550	struct tegra_dma_desc *dma_desc;
 551
 552	while (!list_empty(&tdc->pending_sg_req)) {
 553		sgreq = list_first_entry(&tdc->pending_sg_req,
 554						typeof(*sgreq), node);
 555		list_move_tail(&sgreq->node, &tdc->free_sg_req);
 556		if (sgreq->last_sg) {
 557			dma_desc = sgreq->dma_desc;
 558			dma_desc->dma_status = DMA_ERROR;
 559			list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 560
 561			/* Add in cb list if it is not there. */
 562			if (!dma_desc->cb_count)
 563				list_add_tail(&dma_desc->cb_node,
 564							&tdc->cb_desc);
 565			dma_desc->cb_count++;
 566		}
 567	}
 568	tdc->isr_handler = NULL;
 569}
 570
 571static bool handle_continuous_head_request(struct tegra_dma_channel *tdc,
 572		struct tegra_dma_sg_req *last_sg_req, bool to_terminate)
 573{
 574	struct tegra_dma_sg_req *hsgreq = NULL;
 575
 576	if (list_empty(&tdc->pending_sg_req)) {
 577		dev_err(tdc2dev(tdc), "Dma is running without req\n");
 578		tegra_dma_stop(tdc);
 579		return false;
 580	}
 581
 582	/*
 583	 * Check that head req on list should be in flight.
 584	 * If it is not in flight then abort transfer as
 585	 * looping of transfer can not continue.
 586	 */
 587	hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
 588	if (!hsgreq->configured) {
 589		tegra_dma_stop(tdc);
 590		dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n");
 
 591		tegra_dma_abort_all(tdc);
 592		return false;
 593	}
 594
 595	/* Configure next request */
 596	if (!to_terminate)
 597		tdc_configure_next_head_desc(tdc);
 
 598	return true;
 599}
 600
 601static void handle_once_dma_done(struct tegra_dma_channel *tdc,
 602	bool to_terminate)
 603{
 
 604	struct tegra_dma_sg_req *sgreq;
 605	struct tegra_dma_desc *dma_desc;
 606
 607	tdc->busy = false;
 608	sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
 609	dma_desc = sgreq->dma_desc;
 610	dma_desc->bytes_transferred += sgreq->req_len;
 611
 612	list_del(&sgreq->node);
 613	if (sgreq->last_sg) {
 614		dma_desc->dma_status = DMA_COMPLETE;
 615		dma_cookie_complete(&dma_desc->txd);
 616		if (!dma_desc->cb_count)
 617			list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
 618		dma_desc->cb_count++;
 619		list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 620	}
 621	list_add_tail(&sgreq->node, &tdc->free_sg_req);
 622
 623	/* Do not start DMA if it is going to be terminate */
 624	if (to_terminate || list_empty(&tdc->pending_sg_req))
 625		return;
 626
 
 
 
 
 
 627	tdc_start_head_req(tdc);
 628}
 629
 630static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
 631		bool to_terminate)
 632{
 
 633	struct tegra_dma_sg_req *sgreq;
 634	struct tegra_dma_desc *dma_desc;
 635	bool st;
 636
 637	sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
 638	dma_desc = sgreq->dma_desc;
 639	dma_desc->bytes_transferred += sgreq->req_len;
 
 
 
 640
 641	/* Callback need to be call */
 642	if (!dma_desc->cb_count)
 643		list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
 644	dma_desc->cb_count++;
 645
 
 
 646	/* If not last req then put at end of pending list */
 647	if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) {
 648		list_move_tail(&sgreq->node, &tdc->pending_sg_req);
 649		sgreq->configured = false;
 650		st = handle_continuous_head_request(tdc, sgreq, to_terminate);
 651		if (!st)
 652			dma_desc->dma_status = DMA_ERROR;
 653	}
 654}
 655
 656static void tegra_dma_tasklet(unsigned long data)
 657{
 658	struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
 659	struct dmaengine_desc_callback cb;
 660	struct tegra_dma_desc *dma_desc;
 
 661	unsigned long flags;
 662	int cb_count;
 663
 664	spin_lock_irqsave(&tdc->lock, flags);
 665	while (!list_empty(&tdc->cb_desc)) {
 666		dma_desc  = list_first_entry(&tdc->cb_desc,
 667					typeof(*dma_desc), cb_node);
 668		list_del(&dma_desc->cb_node);
 669		dmaengine_desc_get_callback(&dma_desc->txd, &cb);
 670		cb_count = dma_desc->cb_count;
 671		dma_desc->cb_count = 0;
 
 
 672		spin_unlock_irqrestore(&tdc->lock, flags);
 673		while (cb_count--)
 674			dmaengine_desc_callback_invoke(&cb, NULL);
 675		spin_lock_irqsave(&tdc->lock, flags);
 676	}
 677	spin_unlock_irqrestore(&tdc->lock, flags);
 678}
 679
 680static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
 681{
 682	struct tegra_dma_channel *tdc = dev_id;
 683	unsigned long status;
 684	unsigned long flags;
 685
 686	spin_lock_irqsave(&tdc->lock, flags);
 687
 
 688	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 689	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 690		tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 691		tdc->isr_handler(tdc, false);
 692		tasklet_schedule(&tdc->tasklet);
 693		spin_unlock_irqrestore(&tdc->lock, flags);
 
 694		return IRQ_HANDLED;
 695	}
 696
 697	spin_unlock_irqrestore(&tdc->lock, flags);
 698	dev_info(tdc2dev(tdc),
 699		"Interrupt already served status 0x%08lx\n", status);
 
 700	return IRQ_NONE;
 701}
 702
 703static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd)
 704{
 705	struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd);
 706	struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan);
 707	unsigned long flags;
 708	dma_cookie_t cookie;
 709
 710	spin_lock_irqsave(&tdc->lock, flags);
 711	dma_desc->dma_status = DMA_IN_PROGRESS;
 712	cookie = dma_cookie_assign(&dma_desc->txd);
 713	list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req);
 714	spin_unlock_irqrestore(&tdc->lock, flags);
 
 715	return cookie;
 716}
 717
 718static void tegra_dma_issue_pending(struct dma_chan *dc)
 719{
 720	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 721	unsigned long flags;
 
 722
 723	spin_lock_irqsave(&tdc->lock, flags);
 724	if (list_empty(&tdc->pending_sg_req)) {
 725		dev_err(tdc2dev(tdc), "No DMA request\n");
 726		goto end;
 727	}
 728	if (!tdc->busy) {
 
 
 
 
 
 
 729		tdc_start_head_req(tdc);
 730
 731		/* Continuous single mode: Configure next req */
 732		if (tdc->cyclic) {
 733			/*
 734			 * Wait for 1 burst time for configure DMA for
 735			 * next transfer.
 736			 */
 737			udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 738			tdc_configure_next_head_desc(tdc);
 739		}
 740	}
 741end:
 742	spin_unlock_irqrestore(&tdc->lock, flags);
 743}
 744
 745static int tegra_dma_terminate_all(struct dma_chan *dc)
 746{
 747	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 
 748	struct tegra_dma_sg_req *sgreq;
 749	struct tegra_dma_desc *dma_desc;
 750	unsigned long flags;
 751	unsigned long status;
 752	unsigned long wcount;
 753	bool was_busy;
 754
 755	spin_lock_irqsave(&tdc->lock, flags);
 756	if (list_empty(&tdc->pending_sg_req)) {
 757		spin_unlock_irqrestore(&tdc->lock, flags);
 758		return 0;
 759	}
 760
 761	if (!tdc->busy)
 762		goto skip_dma_stop;
 763
 764	/* Pause DMA before checking the queue status */
 765	tegra_dma_pause(tdc, true);
 766
 767	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 768	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 769		dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
 770		tdc->isr_handler(tdc, true);
 771		status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 772	}
 773	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 774		wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER);
 775	else
 776		wcount = status;
 777
 778	was_busy = tdc->busy;
 779	tegra_dma_stop(tdc);
 780
 781	if (!list_empty(&tdc->pending_sg_req) && was_busy) {
 782		sgreq = list_first_entry(&tdc->pending_sg_req,
 783					typeof(*sgreq), node);
 784		sgreq->dma_desc->bytes_transferred +=
 785				get_current_xferred_count(tdc, sgreq, wcount);
 786	}
 787	tegra_dma_resume(tdc);
 788
 
 
 
 789skip_dma_stop:
 790	tegra_dma_abort_all(tdc);
 791
 792	while (!list_empty(&tdc->cb_desc)) {
 793		dma_desc  = list_first_entry(&tdc->cb_desc,
 794					typeof(*dma_desc), cb_node);
 795		list_del(&dma_desc->cb_node);
 796		dma_desc->cb_count = 0;
 797	}
 798	spin_unlock_irqrestore(&tdc->lock, flags);
 
 799	return 0;
 800}
 801
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 802static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
 803	dma_cookie_t cookie, struct dma_tx_state *txstate)
 
 804{
 805	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 806	struct tegra_dma_desc *dma_desc;
 807	struct tegra_dma_sg_req *sg_req;
 808	enum dma_status ret;
 809	unsigned long flags;
 810	unsigned int residual;
 
 811
 812	ret = dma_cookie_status(dc, cookie, txstate);
 813	if (ret == DMA_COMPLETE)
 814		return ret;
 815
 816	spin_lock_irqsave(&tdc->lock, flags);
 817
 818	/* Check on wait_ack desc status */
 819	list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
 820		if (dma_desc->txd.cookie == cookie) {
 821			ret = dma_desc->dma_status;
 822			goto found;
 823		}
 824	}
 825
 826	/* Check in pending list */
 827	list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
 828		dma_desc = sg_req->dma_desc;
 829		if (dma_desc->txd.cookie == cookie) {
 
 830			ret = dma_desc->dma_status;
 831			goto found;
 832		}
 833	}
 834
 835	dev_dbg(tdc2dev(tdc), "cookie %d not found\n", cookie);
 836	dma_desc = NULL;
 837
 838found:
 839	if (dma_desc && txstate) {
 840		residual = dma_desc->bytes_requested -
 841			   (dma_desc->bytes_transferred %
 842			    dma_desc->bytes_requested);
 843		dma_set_residue(txstate, residual);
 844	}
 845
 
 846	spin_unlock_irqrestore(&tdc->lock, flags);
 
 847	return ret;
 848}
 849
 850static inline int get_bus_width(struct tegra_dma_channel *tdc,
 851		enum dma_slave_buswidth slave_bw)
 852{
 853	switch (slave_bw) {
 854	case DMA_SLAVE_BUSWIDTH_1_BYTE:
 855		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8;
 856	case DMA_SLAVE_BUSWIDTH_2_BYTES:
 857		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16;
 858	case DMA_SLAVE_BUSWIDTH_4_BYTES:
 859		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
 860	case DMA_SLAVE_BUSWIDTH_8_BYTES:
 861		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64;
 862	default:
 863		dev_warn(tdc2dev(tdc),
 864			"slave bw is not supported, using 32bits\n");
 865		return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
 866	}
 867}
 868
 869static inline int get_burst_size(struct tegra_dma_channel *tdc,
 870	u32 burst_size, enum dma_slave_buswidth slave_bw, int len)
 
 
 871{
 872	int burst_byte;
 873	int burst_ahb_width;
 874
 875	/*
 876	 * burst_size from client is in terms of the bus_width.
 877	 * convert them into AHB memory width which is 4 byte.
 878	 */
 879	burst_byte = burst_size * slave_bw;
 880	burst_ahb_width = burst_byte / 4;
 881
 882	/* If burst size is 0 then calculate the burst size based on length */
 883	if (!burst_ahb_width) {
 884		if (len & 0xF)
 885			return TEGRA_APBDMA_AHBSEQ_BURST_1;
 886		else if ((len >> 4) & 0x1)
 887			return TEGRA_APBDMA_AHBSEQ_BURST_4;
 888		else
 889			return TEGRA_APBDMA_AHBSEQ_BURST_8;
 890	}
 891	if (burst_ahb_width < 4)
 892		return TEGRA_APBDMA_AHBSEQ_BURST_1;
 893	else if (burst_ahb_width < 8)
 894		return TEGRA_APBDMA_AHBSEQ_BURST_4;
 895	else
 896		return TEGRA_APBDMA_AHBSEQ_BURST_8;
 897}
 898
 899static int get_transfer_param(struct tegra_dma_channel *tdc,
 900	enum dma_transfer_direction direction, unsigned long *apb_addr,
 901	unsigned long *apb_seq,	unsigned long *csr, unsigned int *burst_size,
 902	enum dma_slave_buswidth *slave_bw)
 
 
 
 903{
 904	switch (direction) {
 905	case DMA_MEM_TO_DEV:
 906		*apb_addr = tdc->dma_sconfig.dst_addr;
 907		*apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width);
 908		*burst_size = tdc->dma_sconfig.dst_maxburst;
 909		*slave_bw = tdc->dma_sconfig.dst_addr_width;
 910		*csr = TEGRA_APBDMA_CSR_DIR;
 911		return 0;
 912
 913	case DMA_DEV_TO_MEM:
 914		*apb_addr = tdc->dma_sconfig.src_addr;
 915		*apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width);
 916		*burst_size = tdc->dma_sconfig.src_maxburst;
 917		*slave_bw = tdc->dma_sconfig.src_addr_width;
 918		*csr = 0;
 919		return 0;
 920
 921	default:
 922		dev_err(tdc2dev(tdc), "Dma direction is not supported\n");
 923		return -EINVAL;
 924	}
 
 925	return -EINVAL;
 926}
 927
 928static void tegra_dma_prep_wcount(struct tegra_dma_channel *tdc,
 929	struct tegra_dma_channel_regs *ch_regs, u32 len)
 
 930{
 931	u32 len_field = (len - 4) & 0xFFFC;
 932
 933	if (tdc->tdma->chip_data->support_separate_wcount_reg)
 934		ch_regs->wcount = len_field;
 935	else
 936		ch_regs->csr |= len_field;
 937}
 938
 939static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
 940	struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len,
 941	enum dma_transfer_direction direction, unsigned long flags,
 942	void *context)
 
 
 
 943{
 944	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 
 
 
 945	struct tegra_dma_desc *dma_desc;
 
 
 
 946	unsigned int i;
 947	struct scatterlist *sg;
 948	unsigned long csr, ahb_seq, apb_ptr, apb_seq;
 949	struct list_head req_list;
 950	struct tegra_dma_sg_req  *sg_req = NULL;
 951	u32 burst_size;
 952	enum dma_slave_buswidth slave_bw;
 953
 954	if (!tdc->config_init) {
 955		dev_err(tdc2dev(tdc), "dma channel is not configured\n");
 956		return NULL;
 957	}
 958	if (sg_len < 1) {
 959		dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
 960		return NULL;
 961	}
 962
 963	if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
 964				&burst_size, &slave_bw) < 0)
 965		return NULL;
 966
 967	INIT_LIST_HEAD(&req_list);
 968
 969	ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
 970	ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
 971					TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
 972	ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
 973
 974	csr |= TEGRA_APBDMA_CSR_ONCE;
 975
 976	if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) {
 977		csr |= TEGRA_APBDMA_CSR_FLOW;
 978		csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
 979	}
 980
 981	if (flags & DMA_PREP_INTERRUPT)
 982		csr |= TEGRA_APBDMA_CSR_IE_EOC;
 
 
 
 
 983
 984	apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
 985
 986	dma_desc = tegra_dma_desc_get(tdc);
 987	if (!dma_desc) {
 988		dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
 989		return NULL;
 990	}
 991	INIT_LIST_HEAD(&dma_desc->tx_list);
 992	INIT_LIST_HEAD(&dma_desc->cb_node);
 993	dma_desc->cb_count = 0;
 994	dma_desc->bytes_requested = 0;
 995	dma_desc->bytes_transferred = 0;
 996	dma_desc->dma_status = DMA_IN_PROGRESS;
 997
 998	/* Make transfer requests */
 999	for_each_sg(sgl, sg, sg_len, i) {
1000		u32 len, mem;
1001
1002		mem = sg_dma_address(sg);
1003		len = sg_dma_len(sg);
1004
1005		if ((len & 3) || (mem & 3) ||
1006				(len > tdc->tdma->chip_data->max_dma_count)) {
1007			dev_err(tdc2dev(tdc),
1008				"Dma length/memory address is not supported\n");
1009			tegra_dma_desc_put(tdc, dma_desc);
1010			return NULL;
1011		}
1012
1013		sg_req = tegra_dma_sg_req_get(tdc);
1014		if (!sg_req) {
1015			dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1016			tegra_dma_desc_put(tdc, dma_desc);
1017			return NULL;
1018		}
1019
1020		ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1021		dma_desc->bytes_requested += len;
1022
1023		sg_req->ch_regs.apb_ptr = apb_ptr;
1024		sg_req->ch_regs.ahb_ptr = mem;
1025		sg_req->ch_regs.csr = csr;
1026		tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1027		sg_req->ch_regs.apb_seq = apb_seq;
1028		sg_req->ch_regs.ahb_seq = ahb_seq;
1029		sg_req->configured = false;
1030		sg_req->last_sg = false;
1031		sg_req->dma_desc = dma_desc;
1032		sg_req->req_len = len;
1033
1034		list_add_tail(&sg_req->node, &dma_desc->tx_list);
1035	}
1036	sg_req->last_sg = true;
1037	if (flags & DMA_CTRL_ACK)
1038		dma_desc->txd.flags = DMA_CTRL_ACK;
1039
1040	/*
1041	 * Make sure that mode should not be conflicting with currently
1042	 * configured mode.
1043	 */
1044	if (!tdc->isr_handler) {
1045		tdc->isr_handler = handle_once_dma_done;
1046		tdc->cyclic = false;
1047	} else {
1048		if (tdc->cyclic) {
1049			dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n");
1050			tegra_dma_desc_put(tdc, dma_desc);
1051			return NULL;
1052		}
1053	}
1054
1055	return &dma_desc->txd;
1056}
1057
1058static struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
1059	struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
1060	size_t period_len, enum dma_transfer_direction direction,
1061	unsigned long flags)
 
 
1062{
1063	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1064	struct tegra_dma_desc *dma_desc = NULL;
1065	struct tegra_dma_sg_req *sg_req = NULL;
1066	unsigned long csr, ahb_seq, apb_ptr, apb_seq;
1067	int len;
1068	size_t remain_len;
1069	dma_addr_t mem = buf_addr;
1070	u32 burst_size;
1071	enum dma_slave_buswidth slave_bw;
1072
1073	if (!buf_len || !period_len) {
1074		dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
1075		return NULL;
1076	}
1077
1078	if (!tdc->config_init) {
1079		dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
1080		return NULL;
1081	}
1082
1083	/*
1084	 * We allow to take more number of requests till DMA is
1085	 * not started. The driver will loop over all requests.
1086	 * Once DMA is started then new requests can be queued only after
1087	 * terminating the DMA.
1088	 */
1089	if (tdc->busy) {
1090		dev_err(tdc2dev(tdc), "Request not allowed when dma running\n");
1091		return NULL;
1092	}
1093
1094	/*
1095	 * We only support cycle transfer when buf_len is multiple of
1096	 * period_len.
1097	 */
1098	if (buf_len % period_len) {
1099		dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
1100		return NULL;
1101	}
1102
1103	len = period_len;
1104	if ((len & 3) || (buf_addr & 3) ||
1105			(len > tdc->tdma->chip_data->max_dma_count)) {
1106		dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
1107		return NULL;
1108	}
1109
1110	if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
1111				&burst_size, &slave_bw) < 0)
1112		return NULL;
1113
1114	ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
1115	ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
1116					TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
1117	ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
1118
1119	if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) {
1120		csr |= TEGRA_APBDMA_CSR_FLOW;
1121		csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
1122	}
1123
1124	if (flags & DMA_PREP_INTERRUPT)
1125		csr |= TEGRA_APBDMA_CSR_IE_EOC;
 
 
 
 
1126
1127	apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
1128
1129	dma_desc = tegra_dma_desc_get(tdc);
1130	if (!dma_desc) {
1131		dev_err(tdc2dev(tdc), "not enough descriptors available\n");
1132		return NULL;
1133	}
1134
1135	INIT_LIST_HEAD(&dma_desc->tx_list);
1136	INIT_LIST_HEAD(&dma_desc->cb_node);
1137	dma_desc->cb_count = 0;
1138
1139	dma_desc->bytes_transferred = 0;
1140	dma_desc->bytes_requested = buf_len;
1141	remain_len = buf_len;
1142
1143	/* Split transfer equal to period size */
1144	while (remain_len) {
1145		sg_req = tegra_dma_sg_req_get(tdc);
1146		if (!sg_req) {
1147			dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1148			tegra_dma_desc_put(tdc, dma_desc);
1149			return NULL;
1150		}
1151
1152		ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1153		sg_req->ch_regs.apb_ptr = apb_ptr;
1154		sg_req->ch_regs.ahb_ptr = mem;
1155		sg_req->ch_regs.csr = csr;
1156		tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1157		sg_req->ch_regs.apb_seq = apb_seq;
1158		sg_req->ch_regs.ahb_seq = ahb_seq;
1159		sg_req->configured = false;
1160		sg_req->last_sg = false;
1161		sg_req->dma_desc = dma_desc;
1162		sg_req->req_len = len;
1163
1164		list_add_tail(&sg_req->node, &dma_desc->tx_list);
1165		remain_len -= len;
1166		mem += len;
1167	}
1168	sg_req->last_sg = true;
1169	if (flags & DMA_CTRL_ACK)
1170		dma_desc->txd.flags = DMA_CTRL_ACK;
1171
1172	/*
1173	 * Make sure that mode should not be conflicting with currently
1174	 * configured mode.
1175	 */
1176	if (!tdc->isr_handler) {
1177		tdc->isr_handler = handle_cont_sngl_cycle_dma_done;
1178		tdc->cyclic = true;
1179	} else {
1180		if (!tdc->cyclic) {
1181			dev_err(tdc2dev(tdc), "DMA configuration conflict\n");
1182			tegra_dma_desc_put(tdc, dma_desc);
1183			return NULL;
1184		}
1185	}
1186
1187	return &dma_desc->txd;
1188}
1189
1190static int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
1191{
1192	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1193	struct tegra_dma *tdma = tdc->tdma;
1194	int ret;
1195
1196	dma_cookie_init(&tdc->dma_chan);
1197	tdc->config_init = false;
1198
1199	ret = pm_runtime_get_sync(tdma->dev);
1200	if (ret < 0)
1201		return ret;
1202
1203	return 0;
1204}
1205
1206static void tegra_dma_free_chan_resources(struct dma_chan *dc)
1207{
1208	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1209	struct tegra_dma *tdma = tdc->tdma;
1210	struct tegra_dma_desc *dma_desc;
1211	struct tegra_dma_sg_req *sg_req;
1212	struct list_head dma_desc_list;
1213	struct list_head sg_req_list;
1214	unsigned long flags;
1215
1216	INIT_LIST_HEAD(&dma_desc_list);
1217	INIT_LIST_HEAD(&sg_req_list);
1218
1219	dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
1220
1221	if (tdc->busy)
1222		tegra_dma_terminate_all(dc);
1223
1224	spin_lock_irqsave(&tdc->lock, flags);
1225	list_splice_init(&tdc->pending_sg_req, &sg_req_list);
1226	list_splice_init(&tdc->free_sg_req, &sg_req_list);
1227	list_splice_init(&tdc->free_dma_desc, &dma_desc_list);
1228	INIT_LIST_HEAD(&tdc->cb_desc);
1229	tdc->config_init = false;
1230	tdc->isr_handler = NULL;
1231	spin_unlock_irqrestore(&tdc->lock, flags);
1232
1233	while (!list_empty(&dma_desc_list)) {
1234		dma_desc = list_first_entry(&dma_desc_list,
1235					typeof(*dma_desc), node);
1236		list_del(&dma_desc->node);
1237		kfree(dma_desc);
1238	}
1239
1240	while (!list_empty(&sg_req_list)) {
1241		sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node);
1242		list_del(&sg_req->node);
1243		kfree(sg_req);
1244	}
1245	pm_runtime_put(tdma->dev);
1246
1247	tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1248}
1249
1250static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
1251					   struct of_dma *ofdma)
1252{
1253	struct tegra_dma *tdma = ofdma->of_dma_data;
 
1254	struct dma_chan *chan;
1255	struct tegra_dma_channel *tdc;
1256
1257	if (dma_spec->args[0] > TEGRA_APBDMA_CSR_REQ_SEL_MASK) {
1258		dev_err(tdma->dev, "Invalid slave id: %d\n", dma_spec->args[0]);
1259		return NULL;
1260	}
1261
1262	chan = dma_get_any_slave_channel(&tdma->dma_dev);
1263	if (!chan)
1264		return NULL;
1265
1266	tdc = to_tegra_dma_chan(chan);
1267	tdc->slave_id = dma_spec->args[0];
1268
1269	return chan;
1270}
1271
1272/* Tegra20 specific DMA controller information */
1273static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
1274	.nr_channels		= 16,
1275	.channel_reg_size	= 0x20,
1276	.max_dma_count		= 1024UL * 64,
1277	.support_channel_pause	= false,
1278	.support_separate_wcount_reg = false,
1279};
1280
1281/* Tegra30 specific DMA controller information */
1282static const struct tegra_dma_chip_data tegra30_dma_chip_data = {
1283	.nr_channels		= 32,
1284	.channel_reg_size	= 0x20,
1285	.max_dma_count		= 1024UL * 64,
1286	.support_channel_pause	= false,
1287	.support_separate_wcount_reg = false,
1288};
1289
1290/* Tegra114 specific DMA controller information */
1291static const struct tegra_dma_chip_data tegra114_dma_chip_data = {
1292	.nr_channels		= 32,
1293	.channel_reg_size	= 0x20,
1294	.max_dma_count		= 1024UL * 64,
1295	.support_channel_pause	= true,
1296	.support_separate_wcount_reg = false,
1297};
1298
1299/* Tegra148 specific DMA controller information */
1300static const struct tegra_dma_chip_data tegra148_dma_chip_data = {
1301	.nr_channels		= 32,
1302	.channel_reg_size	= 0x40,
1303	.max_dma_count		= 1024UL * 64,
1304	.support_channel_pause	= true,
1305	.support_separate_wcount_reg = true,
1306};
1307
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1308static int tegra_dma_probe(struct platform_device *pdev)
1309{
1310	struct resource *res;
1311	struct tegra_dma *tdma;
 
 
1312	int ret;
1313	int i;
1314	const struct tegra_dma_chip_data *cdata;
1315
1316	cdata = of_device_get_match_data(&pdev->dev);
1317	if (!cdata) {
1318		dev_err(&pdev->dev, "Error: No device match data found\n");
1319		return -ENODEV;
1320	}
1321
1322	tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels *
1323			sizeof(struct tegra_dma_channel), GFP_KERNEL);
1324	if (!tdma)
1325		return -ENOMEM;
1326
1327	tdma->dev = &pdev->dev;
1328	tdma->chip_data = cdata;
1329	platform_set_drvdata(pdev, tdma);
1330
1331	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1332	tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
1333	if (IS_ERR(tdma->base_addr))
1334		return PTR_ERR(tdma->base_addr);
1335
1336	tdma->dma_clk = devm_clk_get(&pdev->dev, NULL);
1337	if (IS_ERR(tdma->dma_clk)) {
1338		dev_err(&pdev->dev, "Error: Missing controller clock\n");
1339		return PTR_ERR(tdma->dma_clk);
1340	}
1341
1342	tdma->rst = devm_reset_control_get(&pdev->dev, "dma");
1343	if (IS_ERR(tdma->rst)) {
1344		dev_err(&pdev->dev, "Error: Missing reset\n");
1345		return PTR_ERR(tdma->rst);
1346	}
1347
1348	spin_lock_init(&tdma->global_lock);
1349
1350	pm_runtime_enable(&pdev->dev);
1351	if (!pm_runtime_enabled(&pdev->dev))
1352		ret = tegra_dma_runtime_resume(&pdev->dev);
1353	else
1354		ret = pm_runtime_get_sync(&pdev->dev);
1355
1356	if (ret < 0) {
1357		pm_runtime_disable(&pdev->dev);
1358		return ret;
1359	}
1360
1361	/* Reset DMA controller */
1362	reset_control_assert(tdma->rst);
1363	udelay(2);
1364	reset_control_deassert(tdma->rst);
1365
1366	/* Enable global DMA registers */
1367	tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE);
1368	tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1369	tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
1370
1371	pm_runtime_put(&pdev->dev);
1372
1373	INIT_LIST_HEAD(&tdma->dma_dev.channels);
1374	for (i = 0; i < cdata->nr_channels; i++) {
1375		struct tegra_dma_channel *tdc = &tdma->channels[i];
 
1376
1377		tdc->chan_addr = tdma->base_addr +
1378				 TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET +
1379				 (i * cdata->channel_reg_size);
1380
1381		res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
1382		if (!res) {
1383			ret = -EINVAL;
1384			dev_err(&pdev->dev, "No irq resource for chan %d\n", i);
1385			goto err_irq;
1386		}
1387		tdc->irq = res->start;
1388		snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i);
1389		ret = request_irq(tdc->irq, tegra_dma_isr, 0, tdc->name, tdc);
 
1390		if (ret) {
1391			dev_err(&pdev->dev,
1392				"request_irq failed with err %d channel %d\n",
1393				ret, i);
1394			goto err_irq;
1395		}
1396
1397		tdc->dma_chan.device = &tdma->dma_dev;
1398		dma_cookie_init(&tdc->dma_chan);
1399		list_add_tail(&tdc->dma_chan.device_node,
1400				&tdma->dma_dev.channels);
1401		tdc->tdma = tdma;
1402		tdc->id = i;
1403		tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1404
1405		tasklet_init(&tdc->tasklet, tegra_dma_tasklet,
1406				(unsigned long)tdc);
1407		spin_lock_init(&tdc->lock);
 
1408
1409		INIT_LIST_HEAD(&tdc->pending_sg_req);
1410		INIT_LIST_HEAD(&tdc->free_sg_req);
1411		INIT_LIST_HEAD(&tdc->free_dma_desc);
1412		INIT_LIST_HEAD(&tdc->cb_desc);
1413	}
1414
1415	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
1416	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
1417	dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
1418
1419	tdma->global_pause_count = 0;
1420	tdma->dma_dev.dev = &pdev->dev;
1421	tdma->dma_dev.device_alloc_chan_resources =
1422					tegra_dma_alloc_chan_resources;
1423	tdma->dma_dev.device_free_chan_resources =
1424					tegra_dma_free_chan_resources;
1425	tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg;
1426	tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic;
1427	tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1428		BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1429		BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1430		BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1431	tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1432		BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1433		BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1434		BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1435	tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1436	/*
1437	 * XXX The hardware appears to support
1438	 * DMA_RESIDUE_GRANULARITY_BURST-level reporting, but it's
1439	 * only used by this driver during tegra_dma_terminate_all()
1440	 */
1441	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1442	tdma->dma_dev.device_config = tegra_dma_slave_config;
1443	tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
 
1444	tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
1445	tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
1446
1447	ret = dma_async_device_register(&tdma->dma_dev);
1448	if (ret < 0) {
1449		dev_err(&pdev->dev,
1450			"Tegra20 APB DMA driver registration failed %d\n", ret);
1451		goto err_irq;
1452	}
1453
1454	ret = of_dma_controller_register(pdev->dev.of_node,
1455					 tegra_dma_of_xlate, tdma);
1456	if (ret < 0) {
1457		dev_err(&pdev->dev,
1458			"Tegra20 APB DMA OF registration failed %d\n", ret);
1459		goto err_unregister_dma_dev;
1460	}
1461
1462	dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n",
1463			cdata->nr_channels);
 
1464	return 0;
1465
1466err_unregister_dma_dev:
1467	dma_async_device_unregister(&tdma->dma_dev);
1468err_irq:
1469	while (--i >= 0) {
1470		struct tegra_dma_channel *tdc = &tdma->channels[i];
1471
1472		free_irq(tdc->irq, tdc);
1473		tasklet_kill(&tdc->tasklet);
1474	}
 
 
1475
1476	pm_runtime_disable(&pdev->dev);
1477	if (!pm_runtime_status_suspended(&pdev->dev))
1478		tegra_dma_runtime_suspend(&pdev->dev);
1479	return ret;
1480}
1481
1482static int tegra_dma_remove(struct platform_device *pdev)
1483{
1484	struct tegra_dma *tdma = platform_get_drvdata(pdev);
1485	int i;
1486	struct tegra_dma_channel *tdc;
1487
 
1488	dma_async_device_unregister(&tdma->dma_dev);
1489
1490	for (i = 0; i < tdma->chip_data->nr_channels; ++i) {
1491		tdc = &tdma->channels[i];
1492		free_irq(tdc->irq, tdc);
1493		tasklet_kill(&tdc->tasklet);
1494	}
1495
1496	pm_runtime_disable(&pdev->dev);
1497	if (!pm_runtime_status_suspended(&pdev->dev))
1498		tegra_dma_runtime_suspend(&pdev->dev);
1499
1500	return 0;
1501}
1502
1503static int tegra_dma_runtime_suspend(struct device *dev)
1504{
1505	struct tegra_dma *tdma = dev_get_drvdata(dev);
1506	int i;
1507
1508	tdma->reg_gen = tdma_read(tdma, TEGRA_APBDMA_GENERAL);
1509	for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1510		struct tegra_dma_channel *tdc = &tdma->channels[i];
1511		struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1512
1513		/* Only save the state of DMA channels that are in use */
1514		if (!tdc->config_init)
1515			continue;
1516
1517		ch_reg->csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
1518		ch_reg->ahb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBPTR);
1519		ch_reg->apb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBPTR);
1520		ch_reg->ahb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBSEQ);
1521		ch_reg->apb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBSEQ);
1522		if (tdma->chip_data->support_separate_wcount_reg)
1523			ch_reg->wcount = tdc_read(tdc,
1524						  TEGRA_APBDMA_CHAN_WCOUNT);
1525	}
1526
1527	clk_disable_unprepare(tdma->dma_clk);
1528
1529	return 0;
1530}
1531
1532static int tegra_dma_runtime_resume(struct device *dev)
1533{
1534	struct tegra_dma *tdma = dev_get_drvdata(dev);
1535	int i, ret;
1536
1537	ret = clk_prepare_enable(tdma->dma_clk);
1538	if (ret < 0) {
1539		dev_err(dev, "clk_enable failed: %d\n", ret);
1540		return ret;
1541	}
1542
1543	tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen);
1544	tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1545	tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
 
 
 
1546
1547	for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1548		struct tegra_dma_channel *tdc = &tdma->channels[i];
1549		struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1550
1551		/* Only restore the state of DMA channels that are in use */
1552		if (!tdc->config_init)
1553			continue;
1554
1555		if (tdma->chip_data->support_separate_wcount_reg)
1556			tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
1557				  ch_reg->wcount);
1558		tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_reg->apb_seq);
1559		tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_reg->apb_ptr);
1560		tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_reg->ahb_seq);
1561		tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_reg->ahb_ptr);
1562		tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
1563			(ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB));
1564	}
1565
1566	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
1567}
1568
1569static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
1570	SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume,
1571			   NULL)
1572	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1573				pm_runtime_force_resume)
1574};
1575
1576static const struct of_device_id tegra_dma_of_match[] = {
1577	{
1578		.compatible = "nvidia,tegra148-apbdma",
1579		.data = &tegra148_dma_chip_data,
1580	}, {
1581		.compatible = "nvidia,tegra114-apbdma",
1582		.data = &tegra114_dma_chip_data,
1583	}, {
1584		.compatible = "nvidia,tegra30-apbdma",
1585		.data = &tegra30_dma_chip_data,
1586	}, {
1587		.compatible = "nvidia,tegra20-apbdma",
1588		.data = &tegra20_dma_chip_data,
1589	}, {
1590	},
1591};
1592MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
1593
1594static struct platform_driver tegra_dmac_driver = {
1595	.driver = {
1596		.name	= "tegra-apbdma",
1597		.pm	= &tegra_dma_dev_pm_ops,
1598		.of_match_table = tegra_dma_of_match,
1599	},
1600	.probe		= tegra_dma_probe,
1601	.remove		= tegra_dma_remove,
1602};
1603
1604module_platform_driver(tegra_dmac_driver);
1605
1606MODULE_ALIAS("platform:tegra20-apbdma");
1607MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver");
1608MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
1609MODULE_LICENSE("GPL v2");