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   1/*
   2 * OMAP DMAengine support
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 as
   6 * published by the Free Software Foundation.
   7 */
   8#include <linux/delay.h>
   9#include <linux/dmaengine.h>
  10#include <linux/dma-mapping.h>
  11#include <linux/err.h>
  12#include <linux/init.h>
  13#include <linux/interrupt.h>
  14#include <linux/list.h>
  15#include <linux/module.h>
  16#include <linux/omap-dma.h>
  17#include <linux/platform_device.h>
  18#include <linux/slab.h>
  19#include <linux/spinlock.h>
  20#include <linux/of_dma.h>
  21#include <linux/of_device.h>
  22
  23#include "virt-dma.h"
  24
  25struct omap_dmadev {
  26	struct dma_device ddev;
  27	spinlock_t lock;
  28	struct tasklet_struct task;
  29	struct list_head pending;
  30	void __iomem *base;
  31	const struct omap_dma_reg *reg_map;
  32	struct omap_system_dma_plat_info *plat;
  33	bool legacy;
  34	spinlock_t irq_lock;
  35	uint32_t irq_enable_mask;
  36	struct omap_chan *lch_map[32];
  37};
  38
  39struct omap_chan {
  40	struct virt_dma_chan vc;
  41	struct list_head node;
  42	void __iomem *channel_base;
  43	const struct omap_dma_reg *reg_map;
  44	uint32_t ccr;
  45
  46	struct dma_slave_config	cfg;
  47	unsigned dma_sig;
  48	bool cyclic;
  49	bool paused;
  50
  51	int dma_ch;
  52	struct omap_desc *desc;
  53	unsigned sgidx;
  54};
  55
  56struct omap_sg {
  57	dma_addr_t addr;
  58	uint32_t en;		/* number of elements (24-bit) */
  59	uint32_t fn;		/* number of frames (16-bit) */
  60};
  61
  62struct omap_desc {
  63	struct virt_dma_desc vd;
  64	enum dma_transfer_direction dir;
  65	dma_addr_t dev_addr;
  66
  67	int16_t fi;		/* for OMAP_DMA_SYNC_PACKET */
  68	uint8_t es;		/* CSDP_DATA_TYPE_xxx */
  69	uint32_t ccr;		/* CCR value */
  70	uint16_t clnk_ctrl;	/* CLNK_CTRL value */
  71	uint16_t cicr;		/* CICR value */
  72	uint32_t csdp;		/* CSDP value */
  73
  74	unsigned sglen;
  75	struct omap_sg sg[0];
  76};
  77
  78enum {
  79	CCR_FS			= BIT(5),
  80	CCR_READ_PRIORITY	= BIT(6),
  81	CCR_ENABLE		= BIT(7),
  82	CCR_AUTO_INIT		= BIT(8),	/* OMAP1 only */
  83	CCR_REPEAT		= BIT(9),	/* OMAP1 only */
  84	CCR_OMAP31_DISABLE	= BIT(10),	/* OMAP1 only */
  85	CCR_SUSPEND_SENSITIVE	= BIT(8),	/* OMAP2+ only */
  86	CCR_RD_ACTIVE		= BIT(9),	/* OMAP2+ only */
  87	CCR_WR_ACTIVE		= BIT(10),	/* OMAP2+ only */
  88	CCR_SRC_AMODE_CONSTANT	= 0 << 12,
  89	CCR_SRC_AMODE_POSTINC	= 1 << 12,
  90	CCR_SRC_AMODE_SGLIDX	= 2 << 12,
  91	CCR_SRC_AMODE_DBLIDX	= 3 << 12,
  92	CCR_DST_AMODE_CONSTANT	= 0 << 14,
  93	CCR_DST_AMODE_POSTINC	= 1 << 14,
  94	CCR_DST_AMODE_SGLIDX	= 2 << 14,
  95	CCR_DST_AMODE_DBLIDX	= 3 << 14,
  96	CCR_CONSTANT_FILL	= BIT(16),
  97	CCR_TRANSPARENT_COPY	= BIT(17),
  98	CCR_BS			= BIT(18),
  99	CCR_SUPERVISOR		= BIT(22),
 100	CCR_PREFETCH		= BIT(23),
 101	CCR_TRIGGER_SRC		= BIT(24),
 102	CCR_BUFFERING_DISABLE	= BIT(25),
 103	CCR_WRITE_PRIORITY	= BIT(26),
 104	CCR_SYNC_ELEMENT	= 0,
 105	CCR_SYNC_FRAME		= CCR_FS,
 106	CCR_SYNC_BLOCK		= CCR_BS,
 107	CCR_SYNC_PACKET		= CCR_BS | CCR_FS,
 108
 109	CSDP_DATA_TYPE_8	= 0,
 110	CSDP_DATA_TYPE_16	= 1,
 111	CSDP_DATA_TYPE_32	= 2,
 112	CSDP_SRC_PORT_EMIFF	= 0 << 2, /* OMAP1 only */
 113	CSDP_SRC_PORT_EMIFS	= 1 << 2, /* OMAP1 only */
 114	CSDP_SRC_PORT_OCP_T1	= 2 << 2, /* OMAP1 only */
 115	CSDP_SRC_PORT_TIPB	= 3 << 2, /* OMAP1 only */
 116	CSDP_SRC_PORT_OCP_T2	= 4 << 2, /* OMAP1 only */
 117	CSDP_SRC_PORT_MPUI	= 5 << 2, /* OMAP1 only */
 118	CSDP_SRC_PACKED		= BIT(6),
 119	CSDP_SRC_BURST_1	= 0 << 7,
 120	CSDP_SRC_BURST_16	= 1 << 7,
 121	CSDP_SRC_BURST_32	= 2 << 7,
 122	CSDP_SRC_BURST_64	= 3 << 7,
 123	CSDP_DST_PORT_EMIFF	= 0 << 9, /* OMAP1 only */
 124	CSDP_DST_PORT_EMIFS	= 1 << 9, /* OMAP1 only */
 125	CSDP_DST_PORT_OCP_T1	= 2 << 9, /* OMAP1 only */
 126	CSDP_DST_PORT_TIPB	= 3 << 9, /* OMAP1 only */
 127	CSDP_DST_PORT_OCP_T2	= 4 << 9, /* OMAP1 only */
 128	CSDP_DST_PORT_MPUI	= 5 << 9, /* OMAP1 only */
 129	CSDP_DST_PACKED		= BIT(13),
 130	CSDP_DST_BURST_1	= 0 << 14,
 131	CSDP_DST_BURST_16	= 1 << 14,
 132	CSDP_DST_BURST_32	= 2 << 14,
 133	CSDP_DST_BURST_64	= 3 << 14,
 134
 135	CICR_TOUT_IE		= BIT(0),	/* OMAP1 only */
 136	CICR_DROP_IE		= BIT(1),
 137	CICR_HALF_IE		= BIT(2),
 138	CICR_FRAME_IE		= BIT(3),
 139	CICR_LAST_IE		= BIT(4),
 140	CICR_BLOCK_IE		= BIT(5),
 141	CICR_PKT_IE		= BIT(7),	/* OMAP2+ only */
 142	CICR_TRANS_ERR_IE	= BIT(8),	/* OMAP2+ only */
 143	CICR_SUPERVISOR_ERR_IE	= BIT(10),	/* OMAP2+ only */
 144	CICR_MISALIGNED_ERR_IE	= BIT(11),	/* OMAP2+ only */
 145	CICR_DRAIN_IE		= BIT(12),	/* OMAP2+ only */
 146	CICR_SUPER_BLOCK_IE	= BIT(14),	/* OMAP2+ only */
 147
 148	CLNK_CTRL_ENABLE_LNK	= BIT(15),
 149};
 150
 151static const unsigned es_bytes[] = {
 152	[CSDP_DATA_TYPE_8] = 1,
 153	[CSDP_DATA_TYPE_16] = 2,
 154	[CSDP_DATA_TYPE_32] = 4,
 155};
 156
 157static struct of_dma_filter_info omap_dma_info = {
 158	.filter_fn = omap_dma_filter_fn,
 159};
 160
 161static inline struct omap_dmadev *to_omap_dma_dev(struct dma_device *d)
 162{
 163	return container_of(d, struct omap_dmadev, ddev);
 164}
 165
 166static inline struct omap_chan *to_omap_dma_chan(struct dma_chan *c)
 167{
 168	return container_of(c, struct omap_chan, vc.chan);
 169}
 170
 171static inline struct omap_desc *to_omap_dma_desc(struct dma_async_tx_descriptor *t)
 172{
 173	return container_of(t, struct omap_desc, vd.tx);
 174}
 175
 176static void omap_dma_desc_free(struct virt_dma_desc *vd)
 177{
 178	kfree(container_of(vd, struct omap_desc, vd));
 179}
 180
 181static void omap_dma_write(uint32_t val, unsigned type, void __iomem *addr)
 182{
 183	switch (type) {
 184	case OMAP_DMA_REG_16BIT:
 185		writew_relaxed(val, addr);
 186		break;
 187	case OMAP_DMA_REG_2X16BIT:
 188		writew_relaxed(val, addr);
 189		writew_relaxed(val >> 16, addr + 2);
 190		break;
 191	case OMAP_DMA_REG_32BIT:
 192		writel_relaxed(val, addr);
 193		break;
 194	default:
 195		WARN_ON(1);
 196	}
 197}
 198
 199static unsigned omap_dma_read(unsigned type, void __iomem *addr)
 200{
 201	unsigned val;
 202
 203	switch (type) {
 204	case OMAP_DMA_REG_16BIT:
 205		val = readw_relaxed(addr);
 206		break;
 207	case OMAP_DMA_REG_2X16BIT:
 208		val = readw_relaxed(addr);
 209		val |= readw_relaxed(addr + 2) << 16;
 210		break;
 211	case OMAP_DMA_REG_32BIT:
 212		val = readl_relaxed(addr);
 213		break;
 214	default:
 215		WARN_ON(1);
 216		val = 0;
 217	}
 218
 219	return val;
 220}
 221
 222static void omap_dma_glbl_write(struct omap_dmadev *od, unsigned reg, unsigned val)
 223{
 224	const struct omap_dma_reg *r = od->reg_map + reg;
 225
 226	WARN_ON(r->stride);
 227
 228	omap_dma_write(val, r->type, od->base + r->offset);
 229}
 230
 231static unsigned omap_dma_glbl_read(struct omap_dmadev *od, unsigned reg)
 232{
 233	const struct omap_dma_reg *r = od->reg_map + reg;
 234
 235	WARN_ON(r->stride);
 236
 237	return omap_dma_read(r->type, od->base + r->offset);
 238}
 239
 240static void omap_dma_chan_write(struct omap_chan *c, unsigned reg, unsigned val)
 241{
 242	const struct omap_dma_reg *r = c->reg_map + reg;
 243
 244	omap_dma_write(val, r->type, c->channel_base + r->offset);
 245}
 246
 247static unsigned omap_dma_chan_read(struct omap_chan *c, unsigned reg)
 248{
 249	const struct omap_dma_reg *r = c->reg_map + reg;
 250
 251	return omap_dma_read(r->type, c->channel_base + r->offset);
 252}
 253
 254static void omap_dma_clear_csr(struct omap_chan *c)
 255{
 256	if (dma_omap1())
 257		omap_dma_chan_read(c, CSR);
 258	else
 259		omap_dma_chan_write(c, CSR, ~0);
 260}
 261
 262static unsigned omap_dma_get_csr(struct omap_chan *c)
 263{
 264	unsigned val = omap_dma_chan_read(c, CSR);
 265
 266	if (!dma_omap1())
 267		omap_dma_chan_write(c, CSR, val);
 268
 269	return val;
 270}
 271
 272static void omap_dma_assign(struct omap_dmadev *od, struct omap_chan *c,
 273	unsigned lch)
 274{
 275	c->channel_base = od->base + od->plat->channel_stride * lch;
 276
 277	od->lch_map[lch] = c;
 278}
 279
 280static void omap_dma_start(struct omap_chan *c, struct omap_desc *d)
 281{
 282	struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
 283
 284	if (__dma_omap15xx(od->plat->dma_attr))
 285		omap_dma_chan_write(c, CPC, 0);
 286	else
 287		omap_dma_chan_write(c, CDAC, 0);
 288
 289	omap_dma_clear_csr(c);
 290
 291	/* Enable interrupts */
 292	omap_dma_chan_write(c, CICR, d->cicr);
 293
 294	/* Enable channel */
 295	omap_dma_chan_write(c, CCR, d->ccr | CCR_ENABLE);
 296}
 297
 298static void omap_dma_stop(struct omap_chan *c)
 299{
 300	struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
 301	uint32_t val;
 302
 303	/* disable irq */
 304	omap_dma_chan_write(c, CICR, 0);
 305
 306	omap_dma_clear_csr(c);
 307
 308	val = omap_dma_chan_read(c, CCR);
 309	if (od->plat->errata & DMA_ERRATA_i541 && val & CCR_TRIGGER_SRC) {
 310		uint32_t sysconfig;
 311		unsigned i;
 312
 313		sysconfig = omap_dma_glbl_read(od, OCP_SYSCONFIG);
 314		val = sysconfig & ~DMA_SYSCONFIG_MIDLEMODE_MASK;
 315		val |= DMA_SYSCONFIG_MIDLEMODE(DMA_IDLEMODE_NO_IDLE);
 316		omap_dma_glbl_write(od, OCP_SYSCONFIG, val);
 317
 318		val = omap_dma_chan_read(c, CCR);
 319		val &= ~CCR_ENABLE;
 320		omap_dma_chan_write(c, CCR, val);
 321
 322		/* Wait for sDMA FIFO to drain */
 323		for (i = 0; ; i++) {
 324			val = omap_dma_chan_read(c, CCR);
 325			if (!(val & (CCR_RD_ACTIVE | CCR_WR_ACTIVE)))
 326				break;
 327
 328			if (i > 100)
 329				break;
 330
 331			udelay(5);
 332		}
 333
 334		if (val & (CCR_RD_ACTIVE | CCR_WR_ACTIVE))
 335			dev_err(c->vc.chan.device->dev,
 336				"DMA drain did not complete on lch %d\n",
 337			        c->dma_ch);
 338
 339		omap_dma_glbl_write(od, OCP_SYSCONFIG, sysconfig);
 340	} else {
 341		val &= ~CCR_ENABLE;
 342		omap_dma_chan_write(c, CCR, val);
 343	}
 344
 345	mb();
 346
 347	if (!__dma_omap15xx(od->plat->dma_attr) && c->cyclic) {
 348		val = omap_dma_chan_read(c, CLNK_CTRL);
 349
 350		if (dma_omap1())
 351			val |= 1 << 14; /* set the STOP_LNK bit */
 352		else
 353			val &= ~CLNK_CTRL_ENABLE_LNK;
 354
 355		omap_dma_chan_write(c, CLNK_CTRL, val);
 356	}
 357}
 358
 359static void omap_dma_start_sg(struct omap_chan *c, struct omap_desc *d,
 360	unsigned idx)
 361{
 362	struct omap_sg *sg = d->sg + idx;
 363	unsigned cxsa, cxei, cxfi;
 364
 365	if (d->dir == DMA_DEV_TO_MEM) {
 366		cxsa = CDSA;
 367		cxei = CDEI;
 368		cxfi = CDFI;
 369	} else {
 370		cxsa = CSSA;
 371		cxei = CSEI;
 372		cxfi = CSFI;
 373	}
 374
 375	omap_dma_chan_write(c, cxsa, sg->addr);
 376	omap_dma_chan_write(c, cxei, 0);
 377	omap_dma_chan_write(c, cxfi, 0);
 378	omap_dma_chan_write(c, CEN, sg->en);
 379	omap_dma_chan_write(c, CFN, sg->fn);
 380
 381	omap_dma_start(c, d);
 382}
 383
 384static void omap_dma_start_desc(struct omap_chan *c)
 385{
 386	struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
 387	struct omap_desc *d;
 388	unsigned cxsa, cxei, cxfi;
 389
 390	if (!vd) {
 391		c->desc = NULL;
 392		return;
 393	}
 394
 395	list_del(&vd->node);
 396
 397	c->desc = d = to_omap_dma_desc(&vd->tx);
 398	c->sgidx = 0;
 399
 400	/*
 401	 * This provides the necessary barrier to ensure data held in
 402	 * DMA coherent memory is visible to the DMA engine prior to
 403	 * the transfer starting.
 404	 */
 405	mb();
 406
 407	omap_dma_chan_write(c, CCR, d->ccr);
 408	if (dma_omap1())
 409		omap_dma_chan_write(c, CCR2, d->ccr >> 16);
 410
 411	if (d->dir == DMA_DEV_TO_MEM) {
 412		cxsa = CSSA;
 413		cxei = CSEI;
 414		cxfi = CSFI;
 415	} else {
 416		cxsa = CDSA;
 417		cxei = CDEI;
 418		cxfi = CDFI;
 419	}
 420
 421	omap_dma_chan_write(c, cxsa, d->dev_addr);
 422	omap_dma_chan_write(c, cxei, 0);
 423	omap_dma_chan_write(c, cxfi, d->fi);
 424	omap_dma_chan_write(c, CSDP, d->csdp);
 425	omap_dma_chan_write(c, CLNK_CTRL, d->clnk_ctrl);
 426
 427	omap_dma_start_sg(c, d, 0);
 428}
 429
 430static void omap_dma_callback(int ch, u16 status, void *data)
 431{
 432	struct omap_chan *c = data;
 433	struct omap_desc *d;
 434	unsigned long flags;
 435
 436	spin_lock_irqsave(&c->vc.lock, flags);
 437	d = c->desc;
 438	if (d) {
 439		if (!c->cyclic) {
 440			if (++c->sgidx < d->sglen) {
 441				omap_dma_start_sg(c, d, c->sgidx);
 442			} else {
 443				omap_dma_start_desc(c);
 444				vchan_cookie_complete(&d->vd);
 445			}
 446		} else {
 447			vchan_cyclic_callback(&d->vd);
 448		}
 449	}
 450	spin_unlock_irqrestore(&c->vc.lock, flags);
 451}
 452
 453/*
 454 * This callback schedules all pending channels.  We could be more
 455 * clever here by postponing allocation of the real DMA channels to
 456 * this point, and freeing them when our virtual channel becomes idle.
 457 *
 458 * We would then need to deal with 'all channels in-use'
 459 */
 460static void omap_dma_sched(unsigned long data)
 461{
 462	struct omap_dmadev *d = (struct omap_dmadev *)data;
 463	LIST_HEAD(head);
 464
 465	spin_lock_irq(&d->lock);
 466	list_splice_tail_init(&d->pending, &head);
 467	spin_unlock_irq(&d->lock);
 468
 469	while (!list_empty(&head)) {
 470		struct omap_chan *c = list_first_entry(&head,
 471			struct omap_chan, node);
 472
 473		spin_lock_irq(&c->vc.lock);
 474		list_del_init(&c->node);
 475		omap_dma_start_desc(c);
 476		spin_unlock_irq(&c->vc.lock);
 477	}
 478}
 479
 480static irqreturn_t omap_dma_irq(int irq, void *devid)
 481{
 482	struct omap_dmadev *od = devid;
 483	unsigned status, channel;
 484
 485	spin_lock(&od->irq_lock);
 486
 487	status = omap_dma_glbl_read(od, IRQSTATUS_L1);
 488	status &= od->irq_enable_mask;
 489	if (status == 0) {
 490		spin_unlock(&od->irq_lock);
 491		return IRQ_NONE;
 492	}
 493
 494	while ((channel = ffs(status)) != 0) {
 495		unsigned mask, csr;
 496		struct omap_chan *c;
 497
 498		channel -= 1;
 499		mask = BIT(channel);
 500		status &= ~mask;
 501
 502		c = od->lch_map[channel];
 503		if (c == NULL) {
 504			/* This should never happen */
 505			dev_err(od->ddev.dev, "invalid channel %u\n", channel);
 506			continue;
 507		}
 508
 509		csr = omap_dma_get_csr(c);
 510		omap_dma_glbl_write(od, IRQSTATUS_L1, mask);
 511
 512		omap_dma_callback(channel, csr, c);
 513	}
 514
 515	spin_unlock(&od->irq_lock);
 516
 517	return IRQ_HANDLED;
 518}
 519
 520static int omap_dma_alloc_chan_resources(struct dma_chan *chan)
 521{
 522	struct omap_dmadev *od = to_omap_dma_dev(chan->device);
 523	struct omap_chan *c = to_omap_dma_chan(chan);
 524	int ret;
 525
 526	if (od->legacy) {
 527		ret = omap_request_dma(c->dma_sig, "DMA engine",
 528				       omap_dma_callback, c, &c->dma_ch);
 529	} else {
 530		ret = omap_request_dma(c->dma_sig, "DMA engine", NULL, NULL,
 531				       &c->dma_ch);
 532	}
 533
 534	dev_dbg(od->ddev.dev, "allocating channel %u for %u\n",
 535		c->dma_ch, c->dma_sig);
 536
 537	if (ret >= 0) {
 538		omap_dma_assign(od, c, c->dma_ch);
 539
 540		if (!od->legacy) {
 541			unsigned val;
 542
 543			spin_lock_irq(&od->irq_lock);
 544			val = BIT(c->dma_ch);
 545			omap_dma_glbl_write(od, IRQSTATUS_L1, val);
 546			od->irq_enable_mask |= val;
 547			omap_dma_glbl_write(od, IRQENABLE_L1, od->irq_enable_mask);
 548
 549			val = omap_dma_glbl_read(od, IRQENABLE_L0);
 550			val &= ~BIT(c->dma_ch);
 551			omap_dma_glbl_write(od, IRQENABLE_L0, val);
 552			spin_unlock_irq(&od->irq_lock);
 553		}
 554	}
 555
 556	if (dma_omap1()) {
 557		if (__dma_omap16xx(od->plat->dma_attr)) {
 558			c->ccr = CCR_OMAP31_DISABLE;
 559			/* Duplicate what plat-omap/dma.c does */
 560			c->ccr |= c->dma_ch + 1;
 561		} else {
 562			c->ccr = c->dma_sig & 0x1f;
 563		}
 564	} else {
 565		c->ccr = c->dma_sig & 0x1f;
 566		c->ccr |= (c->dma_sig & ~0x1f) << 14;
 567	}
 568	if (od->plat->errata & DMA_ERRATA_IFRAME_BUFFERING)
 569		c->ccr |= CCR_BUFFERING_DISABLE;
 570
 571	return ret;
 572}
 573
 574static void omap_dma_free_chan_resources(struct dma_chan *chan)
 575{
 576	struct omap_dmadev *od = to_omap_dma_dev(chan->device);
 577	struct omap_chan *c = to_omap_dma_chan(chan);
 578
 579	if (!od->legacy) {
 580		spin_lock_irq(&od->irq_lock);
 581		od->irq_enable_mask &= ~BIT(c->dma_ch);
 582		omap_dma_glbl_write(od, IRQENABLE_L1, od->irq_enable_mask);
 583		spin_unlock_irq(&od->irq_lock);
 584	}
 585
 586	c->channel_base = NULL;
 587	od->lch_map[c->dma_ch] = NULL;
 588	vchan_free_chan_resources(&c->vc);
 589	omap_free_dma(c->dma_ch);
 590
 591	dev_dbg(od->ddev.dev, "freeing channel for %u\n", c->dma_sig);
 592}
 593
 594static size_t omap_dma_sg_size(struct omap_sg *sg)
 595{
 596	return sg->en * sg->fn;
 597}
 598
 599static size_t omap_dma_desc_size(struct omap_desc *d)
 600{
 601	unsigned i;
 602	size_t size;
 603
 604	for (size = i = 0; i < d->sglen; i++)
 605		size += omap_dma_sg_size(&d->sg[i]);
 606
 607	return size * es_bytes[d->es];
 608}
 609
 610static size_t omap_dma_desc_size_pos(struct omap_desc *d, dma_addr_t addr)
 611{
 612	unsigned i;
 613	size_t size, es_size = es_bytes[d->es];
 614
 615	for (size = i = 0; i < d->sglen; i++) {
 616		size_t this_size = omap_dma_sg_size(&d->sg[i]) * es_size;
 617
 618		if (size)
 619			size += this_size;
 620		else if (addr >= d->sg[i].addr &&
 621			 addr < d->sg[i].addr + this_size)
 622			size += d->sg[i].addr + this_size - addr;
 623	}
 624	return size;
 625}
 626
 627/*
 628 * OMAP 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is
 629 * read before the DMA controller finished disabling the channel.
 630 */
 631static uint32_t omap_dma_chan_read_3_3(struct omap_chan *c, unsigned reg)
 632{
 633	struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
 634	uint32_t val;
 635
 636	val = omap_dma_chan_read(c, reg);
 637	if (val == 0 && od->plat->errata & DMA_ERRATA_3_3)
 638		val = omap_dma_chan_read(c, reg);
 639
 640	return val;
 641}
 642
 643static dma_addr_t omap_dma_get_src_pos(struct omap_chan *c)
 644{
 645	struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
 646	dma_addr_t addr, cdac;
 647
 648	if (__dma_omap15xx(od->plat->dma_attr)) {
 649		addr = omap_dma_chan_read(c, CPC);
 650	} else {
 651		addr = omap_dma_chan_read_3_3(c, CSAC);
 652		cdac = omap_dma_chan_read_3_3(c, CDAC);
 653
 654		/*
 655		 * CDAC == 0 indicates that the DMA transfer on the channel has
 656		 * not been started (no data has been transferred so far).
 657		 * Return the programmed source start address in this case.
 658		 */
 659		if (cdac == 0)
 660			addr = omap_dma_chan_read(c, CSSA);
 661	}
 662
 663	if (dma_omap1())
 664		addr |= omap_dma_chan_read(c, CSSA) & 0xffff0000;
 665
 666	return addr;
 667}
 668
 669static dma_addr_t omap_dma_get_dst_pos(struct omap_chan *c)
 670{
 671	struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
 672	dma_addr_t addr;
 673
 674	if (__dma_omap15xx(od->plat->dma_attr)) {
 675		addr = omap_dma_chan_read(c, CPC);
 676	} else {
 677		addr = omap_dma_chan_read_3_3(c, CDAC);
 678
 679		/*
 680		 * CDAC == 0 indicates that the DMA transfer on the channel
 681		 * has not been started (no data has been transferred so
 682		 * far).  Return the programmed destination start address in
 683		 * this case.
 684		 */
 685		if (addr == 0)
 686			addr = omap_dma_chan_read(c, CDSA);
 687	}
 688
 689	if (dma_omap1())
 690		addr |= omap_dma_chan_read(c, CDSA) & 0xffff0000;
 691
 692	return addr;
 693}
 694
 695static enum dma_status omap_dma_tx_status(struct dma_chan *chan,
 696	dma_cookie_t cookie, struct dma_tx_state *txstate)
 697{
 698	struct omap_chan *c = to_omap_dma_chan(chan);
 699	struct virt_dma_desc *vd;
 700	enum dma_status ret;
 701	unsigned long flags;
 702
 703	ret = dma_cookie_status(chan, cookie, txstate);
 704	if (ret == DMA_COMPLETE || !txstate)
 705		return ret;
 706
 707	spin_lock_irqsave(&c->vc.lock, flags);
 708	vd = vchan_find_desc(&c->vc, cookie);
 709	if (vd) {
 710		txstate->residue = omap_dma_desc_size(to_omap_dma_desc(&vd->tx));
 711	} else if (c->desc && c->desc->vd.tx.cookie == cookie) {
 712		struct omap_desc *d = c->desc;
 713		dma_addr_t pos;
 714
 715		if (d->dir == DMA_MEM_TO_DEV)
 716			pos = omap_dma_get_src_pos(c);
 717		else if (d->dir == DMA_DEV_TO_MEM)
 718			pos = omap_dma_get_dst_pos(c);
 719		else
 720			pos = 0;
 721
 722		txstate->residue = omap_dma_desc_size_pos(d, pos);
 723	} else {
 724		txstate->residue = 0;
 725	}
 726	spin_unlock_irqrestore(&c->vc.lock, flags);
 727
 728	return ret;
 729}
 730
 731static void omap_dma_issue_pending(struct dma_chan *chan)
 732{
 733	struct omap_chan *c = to_omap_dma_chan(chan);
 734	unsigned long flags;
 735
 736	spin_lock_irqsave(&c->vc.lock, flags);
 737	if (vchan_issue_pending(&c->vc) && !c->desc) {
 738		/*
 739		 * c->cyclic is used only by audio and in this case the DMA need
 740		 * to be started without delay.
 741		 */
 742		if (!c->cyclic) {
 743			struct omap_dmadev *d = to_omap_dma_dev(chan->device);
 744			spin_lock(&d->lock);
 745			if (list_empty(&c->node))
 746				list_add_tail(&c->node, &d->pending);
 747			spin_unlock(&d->lock);
 748			tasklet_schedule(&d->task);
 749		} else {
 750			omap_dma_start_desc(c);
 751		}
 752	}
 753	spin_unlock_irqrestore(&c->vc.lock, flags);
 754}
 755
 756static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
 757	struct dma_chan *chan, struct scatterlist *sgl, unsigned sglen,
 758	enum dma_transfer_direction dir, unsigned long tx_flags, void *context)
 759{
 760	struct omap_dmadev *od = to_omap_dma_dev(chan->device);
 761	struct omap_chan *c = to_omap_dma_chan(chan);
 762	enum dma_slave_buswidth dev_width;
 763	struct scatterlist *sgent;
 764	struct omap_desc *d;
 765	dma_addr_t dev_addr;
 766	unsigned i, j = 0, es, en, frame_bytes;
 767	u32 burst;
 768
 769	if (dir == DMA_DEV_TO_MEM) {
 770		dev_addr = c->cfg.src_addr;
 771		dev_width = c->cfg.src_addr_width;
 772		burst = c->cfg.src_maxburst;
 773	} else if (dir == DMA_MEM_TO_DEV) {
 774		dev_addr = c->cfg.dst_addr;
 775		dev_width = c->cfg.dst_addr_width;
 776		burst = c->cfg.dst_maxburst;
 777	} else {
 778		dev_err(chan->device->dev, "%s: bad direction?\n", __func__);
 779		return NULL;
 780	}
 781
 782	/* Bus width translates to the element size (ES) */
 783	switch (dev_width) {
 784	case DMA_SLAVE_BUSWIDTH_1_BYTE:
 785		es = CSDP_DATA_TYPE_8;
 786		break;
 787	case DMA_SLAVE_BUSWIDTH_2_BYTES:
 788		es = CSDP_DATA_TYPE_16;
 789		break;
 790	case DMA_SLAVE_BUSWIDTH_4_BYTES:
 791		es = CSDP_DATA_TYPE_32;
 792		break;
 793	default: /* not reached */
 794		return NULL;
 795	}
 796
 797	/* Now allocate and setup the descriptor. */
 798	d = kzalloc(sizeof(*d) + sglen * sizeof(d->sg[0]), GFP_ATOMIC);
 799	if (!d)
 800		return NULL;
 801
 802	d->dir = dir;
 803	d->dev_addr = dev_addr;
 804	d->es = es;
 805
 806	d->ccr = c->ccr | CCR_SYNC_FRAME;
 807	if (dir == DMA_DEV_TO_MEM)
 808		d->ccr |= CCR_DST_AMODE_POSTINC | CCR_SRC_AMODE_CONSTANT;
 809	else
 810		d->ccr |= CCR_DST_AMODE_CONSTANT | CCR_SRC_AMODE_POSTINC;
 811
 812	d->cicr = CICR_DROP_IE | CICR_BLOCK_IE;
 813	d->csdp = es;
 814
 815	if (dma_omap1()) {
 816		d->cicr |= CICR_TOUT_IE;
 817
 818		if (dir == DMA_DEV_TO_MEM)
 819			d->csdp |= CSDP_DST_PORT_EMIFF | CSDP_SRC_PORT_TIPB;
 820		else
 821			d->csdp |= CSDP_DST_PORT_TIPB | CSDP_SRC_PORT_EMIFF;
 822	} else {
 823		if (dir == DMA_DEV_TO_MEM)
 824			d->ccr |= CCR_TRIGGER_SRC;
 825
 826		d->cicr |= CICR_MISALIGNED_ERR_IE | CICR_TRANS_ERR_IE;
 827	}
 828	if (od->plat->errata & DMA_ERRATA_PARALLEL_CHANNELS)
 829		d->clnk_ctrl = c->dma_ch;
 830
 831	/*
 832	 * Build our scatterlist entries: each contains the address,
 833	 * the number of elements (EN) in each frame, and the number of
 834	 * frames (FN).  Number of bytes for this entry = ES * EN * FN.
 835	 *
 836	 * Burst size translates to number of elements with frame sync.
 837	 * Note: DMA engine defines burst to be the number of dev-width
 838	 * transfers.
 839	 */
 840	en = burst;
 841	frame_bytes = es_bytes[es] * en;
 842	for_each_sg(sgl, sgent, sglen, i) {
 843		d->sg[j].addr = sg_dma_address(sgent);
 844		d->sg[j].en = en;
 845		d->sg[j].fn = sg_dma_len(sgent) / frame_bytes;
 846		j++;
 847	}
 848
 849	d->sglen = j;
 850
 851	return vchan_tx_prep(&c->vc, &d->vd, tx_flags);
 852}
 853
 854static struct dma_async_tx_descriptor *omap_dma_prep_dma_cyclic(
 855	struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
 856	size_t period_len, enum dma_transfer_direction dir, unsigned long flags,
 857	void *context)
 858{
 859	struct omap_dmadev *od = to_omap_dma_dev(chan->device);
 860	struct omap_chan *c = to_omap_dma_chan(chan);
 861	enum dma_slave_buswidth dev_width;
 862	struct omap_desc *d;
 863	dma_addr_t dev_addr;
 864	unsigned es;
 865	u32 burst;
 866
 867	if (dir == DMA_DEV_TO_MEM) {
 868		dev_addr = c->cfg.src_addr;
 869		dev_width = c->cfg.src_addr_width;
 870		burst = c->cfg.src_maxburst;
 871	} else if (dir == DMA_MEM_TO_DEV) {
 872		dev_addr = c->cfg.dst_addr;
 873		dev_width = c->cfg.dst_addr_width;
 874		burst = c->cfg.dst_maxburst;
 875	} else {
 876		dev_err(chan->device->dev, "%s: bad direction?\n", __func__);
 877		return NULL;
 878	}
 879
 880	/* Bus width translates to the element size (ES) */
 881	switch (dev_width) {
 882	case DMA_SLAVE_BUSWIDTH_1_BYTE:
 883		es = CSDP_DATA_TYPE_8;
 884		break;
 885	case DMA_SLAVE_BUSWIDTH_2_BYTES:
 886		es = CSDP_DATA_TYPE_16;
 887		break;
 888	case DMA_SLAVE_BUSWIDTH_4_BYTES:
 889		es = CSDP_DATA_TYPE_32;
 890		break;
 891	default: /* not reached */
 892		return NULL;
 893	}
 894
 895	/* Now allocate and setup the descriptor. */
 896	d = kzalloc(sizeof(*d) + sizeof(d->sg[0]), GFP_ATOMIC);
 897	if (!d)
 898		return NULL;
 899
 900	d->dir = dir;
 901	d->dev_addr = dev_addr;
 902	d->fi = burst;
 903	d->es = es;
 904	d->sg[0].addr = buf_addr;
 905	d->sg[0].en = period_len / es_bytes[es];
 906	d->sg[0].fn = buf_len / period_len;
 907	d->sglen = 1;
 908
 909	d->ccr = c->ccr;
 910	if (dir == DMA_DEV_TO_MEM)
 911		d->ccr |= CCR_DST_AMODE_POSTINC | CCR_SRC_AMODE_CONSTANT;
 912	else
 913		d->ccr |= CCR_DST_AMODE_CONSTANT | CCR_SRC_AMODE_POSTINC;
 914
 915	d->cicr = CICR_DROP_IE;
 916	if (flags & DMA_PREP_INTERRUPT)
 917		d->cicr |= CICR_FRAME_IE;
 918
 919	d->csdp = es;
 920
 921	if (dma_omap1()) {
 922		d->cicr |= CICR_TOUT_IE;
 923
 924		if (dir == DMA_DEV_TO_MEM)
 925			d->csdp |= CSDP_DST_PORT_EMIFF | CSDP_SRC_PORT_MPUI;
 926		else
 927			d->csdp |= CSDP_DST_PORT_MPUI | CSDP_SRC_PORT_EMIFF;
 928	} else {
 929		if (burst)
 930			d->ccr |= CCR_SYNC_PACKET;
 931		else
 932			d->ccr |= CCR_SYNC_ELEMENT;
 933
 934		if (dir == DMA_DEV_TO_MEM)
 935			d->ccr |= CCR_TRIGGER_SRC;
 936
 937		d->cicr |= CICR_MISALIGNED_ERR_IE | CICR_TRANS_ERR_IE;
 938
 939		d->csdp |= CSDP_DST_BURST_64 | CSDP_SRC_BURST_64;
 940	}
 941
 942	if (__dma_omap15xx(od->plat->dma_attr))
 943		d->ccr |= CCR_AUTO_INIT | CCR_REPEAT;
 944	else
 945		d->clnk_ctrl = c->dma_ch | CLNK_CTRL_ENABLE_LNK;
 946
 947	c->cyclic = true;
 948
 949	return vchan_tx_prep(&c->vc, &d->vd, flags);
 950}
 951
 952static int omap_dma_slave_config(struct omap_chan *c, struct dma_slave_config *cfg)
 953{
 954	if (cfg->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
 955	    cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
 956		return -EINVAL;
 957
 958	memcpy(&c->cfg, cfg, sizeof(c->cfg));
 959
 960	return 0;
 961}
 962
 963static int omap_dma_terminate_all(struct omap_chan *c)
 964{
 965	struct omap_dmadev *d = to_omap_dma_dev(c->vc.chan.device);
 966	unsigned long flags;
 967	LIST_HEAD(head);
 968
 969	spin_lock_irqsave(&c->vc.lock, flags);
 970
 971	/* Prevent this channel being scheduled */
 972	spin_lock(&d->lock);
 973	list_del_init(&c->node);
 974	spin_unlock(&d->lock);
 975
 976	/*
 977	 * Stop DMA activity: we assume the callback will not be called
 978	 * after omap_dma_stop() returns (even if it does, it will see
 979	 * c->desc is NULL and exit.)
 980	 */
 981	if (c->desc) {
 982		c->desc = NULL;
 983		/* Avoid stopping the dma twice */
 984		if (!c->paused)
 985			omap_dma_stop(c);
 986	}
 987
 988	if (c->cyclic) {
 989		c->cyclic = false;
 990		c->paused = false;
 991	}
 992
 993	vchan_get_all_descriptors(&c->vc, &head);
 994	spin_unlock_irqrestore(&c->vc.lock, flags);
 995	vchan_dma_desc_free_list(&c->vc, &head);
 996
 997	return 0;
 998}
 999
1000static int omap_dma_pause(struct omap_chan *c)
1001{
1002	/* Pause/Resume only allowed with cyclic mode */
1003	if (!c->cyclic)
1004		return -EINVAL;
1005
1006	if (!c->paused) {
1007		omap_dma_stop(c);
1008		c->paused = true;
1009	}
1010
1011	return 0;
1012}
1013
1014static int omap_dma_resume(struct omap_chan *c)
1015{
1016	/* Pause/Resume only allowed with cyclic mode */
1017	if (!c->cyclic)
1018		return -EINVAL;
1019
1020	if (c->paused) {
1021		omap_dma_start(c, c->desc);
1022		c->paused = false;
1023	}
1024
1025	return 0;
1026}
1027
1028static int omap_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
1029	unsigned long arg)
1030{
1031	struct omap_chan *c = to_omap_dma_chan(chan);
1032	int ret;
1033
1034	switch (cmd) {
1035	case DMA_SLAVE_CONFIG:
1036		ret = omap_dma_slave_config(c, (struct dma_slave_config *)arg);
1037		break;
1038
1039	case DMA_TERMINATE_ALL:
1040		ret = omap_dma_terminate_all(c);
1041		break;
1042
1043	case DMA_PAUSE:
1044		ret = omap_dma_pause(c);
1045		break;
1046
1047	case DMA_RESUME:
1048		ret = omap_dma_resume(c);
1049		break;
1050
1051	default:
1052		ret = -ENXIO;
1053		break;
1054	}
1055
1056	return ret;
1057}
1058
1059static int omap_dma_chan_init(struct omap_dmadev *od, int dma_sig)
1060{
1061	struct omap_chan *c;
1062
1063	c = kzalloc(sizeof(*c), GFP_KERNEL);
1064	if (!c)
1065		return -ENOMEM;
1066
1067	c->reg_map = od->reg_map;
1068	c->dma_sig = dma_sig;
1069	c->vc.desc_free = omap_dma_desc_free;
1070	vchan_init(&c->vc, &od->ddev);
1071	INIT_LIST_HEAD(&c->node);
1072
1073	od->ddev.chancnt++;
1074
1075	return 0;
1076}
1077
1078static void omap_dma_free(struct omap_dmadev *od)
1079{
1080	tasklet_kill(&od->task);
1081	while (!list_empty(&od->ddev.channels)) {
1082		struct omap_chan *c = list_first_entry(&od->ddev.channels,
1083			struct omap_chan, vc.chan.device_node);
1084
1085		list_del(&c->vc.chan.device_node);
1086		tasklet_kill(&c->vc.task);
1087		kfree(c);
1088	}
1089}
1090
1091#define OMAP_DMA_BUSWIDTHS	(BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
1092				 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
1093				 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
1094
1095static int omap_dma_device_slave_caps(struct dma_chan *dchan,
1096				      struct dma_slave_caps *caps)
1097{
1098	caps->src_addr_widths = OMAP_DMA_BUSWIDTHS;
1099	caps->dstn_addr_widths = OMAP_DMA_BUSWIDTHS;
1100	caps->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1101	caps->cmd_pause = true;
1102	caps->cmd_terminate = true;
1103	caps->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1104
1105	return 0;
1106}
1107
1108static int omap_dma_probe(struct platform_device *pdev)
1109{
1110	struct omap_dmadev *od;
1111	struct resource *res;
1112	int rc, i, irq;
1113
1114	od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
1115	if (!od)
1116		return -ENOMEM;
1117
1118	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1119	od->base = devm_ioremap_resource(&pdev->dev, res);
1120	if (IS_ERR(od->base))
1121		return PTR_ERR(od->base);
1122
1123	od->plat = omap_get_plat_info();
1124	if (!od->plat)
1125		return -EPROBE_DEFER;
1126
1127	od->reg_map = od->plat->reg_map;
1128
1129	dma_cap_set(DMA_SLAVE, od->ddev.cap_mask);
1130	dma_cap_set(DMA_CYCLIC, od->ddev.cap_mask);
1131	od->ddev.device_alloc_chan_resources = omap_dma_alloc_chan_resources;
1132	od->ddev.device_free_chan_resources = omap_dma_free_chan_resources;
1133	od->ddev.device_tx_status = omap_dma_tx_status;
1134	od->ddev.device_issue_pending = omap_dma_issue_pending;
1135	od->ddev.device_prep_slave_sg = omap_dma_prep_slave_sg;
1136	od->ddev.device_prep_dma_cyclic = omap_dma_prep_dma_cyclic;
1137	od->ddev.device_control = omap_dma_control;
1138	od->ddev.device_slave_caps = omap_dma_device_slave_caps;
1139	od->ddev.dev = &pdev->dev;
1140	INIT_LIST_HEAD(&od->ddev.channels);
1141	INIT_LIST_HEAD(&od->pending);
1142	spin_lock_init(&od->lock);
1143	spin_lock_init(&od->irq_lock);
1144
1145	tasklet_init(&od->task, omap_dma_sched, (unsigned long)od);
1146
1147	for (i = 0; i < 127; i++) {
1148		rc = omap_dma_chan_init(od, i);
1149		if (rc) {
1150			omap_dma_free(od);
1151			return rc;
1152		}
1153	}
1154
1155	irq = platform_get_irq(pdev, 1);
1156	if (irq <= 0) {
1157		dev_info(&pdev->dev, "failed to get L1 IRQ: %d\n", irq);
1158		od->legacy = true;
1159	} else {
1160		/* Disable all interrupts */
1161		od->irq_enable_mask = 0;
1162		omap_dma_glbl_write(od, IRQENABLE_L1, 0);
1163
1164		rc = devm_request_irq(&pdev->dev, irq, omap_dma_irq,
1165				      IRQF_SHARED, "omap-dma-engine", od);
1166		if (rc)
1167			return rc;
1168	}
1169
1170	rc = dma_async_device_register(&od->ddev);
1171	if (rc) {
1172		pr_warn("OMAP-DMA: failed to register slave DMA engine device: %d\n",
1173			rc);
1174		omap_dma_free(od);
1175		return rc;
1176	}
1177
1178	platform_set_drvdata(pdev, od);
1179
1180	if (pdev->dev.of_node) {
1181		omap_dma_info.dma_cap = od->ddev.cap_mask;
1182
1183		/* Device-tree DMA controller registration */
1184		rc = of_dma_controller_register(pdev->dev.of_node,
1185				of_dma_simple_xlate, &omap_dma_info);
1186		if (rc) {
1187			pr_warn("OMAP-DMA: failed to register DMA controller\n");
1188			dma_async_device_unregister(&od->ddev);
1189			omap_dma_free(od);
1190		}
1191	}
1192
1193	dev_info(&pdev->dev, "OMAP DMA engine driver\n");
1194
1195	return rc;
1196}
1197
1198static int omap_dma_remove(struct platform_device *pdev)
1199{
1200	struct omap_dmadev *od = platform_get_drvdata(pdev);
1201
1202	if (pdev->dev.of_node)
1203		of_dma_controller_free(pdev->dev.of_node);
1204
1205	dma_async_device_unregister(&od->ddev);
1206
1207	if (!od->legacy) {
1208		/* Disable all interrupts */
1209		omap_dma_glbl_write(od, IRQENABLE_L0, 0);
1210	}
1211
1212	omap_dma_free(od);
1213
1214	return 0;
1215}
1216
1217static const struct of_device_id omap_dma_match[] = {
1218	{ .compatible = "ti,omap2420-sdma", },
1219	{ .compatible = "ti,omap2430-sdma", },
1220	{ .compatible = "ti,omap3430-sdma", },
1221	{ .compatible = "ti,omap3630-sdma", },
1222	{ .compatible = "ti,omap4430-sdma", },
1223	{},
1224};
1225MODULE_DEVICE_TABLE(of, omap_dma_match);
1226
1227static struct platform_driver omap_dma_driver = {
1228	.probe	= omap_dma_probe,
1229	.remove	= omap_dma_remove,
1230	.driver = {
1231		.name = "omap-dma-engine",
1232		.owner = THIS_MODULE,
1233		.of_match_table = of_match_ptr(omap_dma_match),
1234	},
1235};
1236
1237bool omap_dma_filter_fn(struct dma_chan *chan, void *param)
1238{
1239	if (chan->device->dev->driver == &omap_dma_driver.driver) {
1240		struct omap_chan *c = to_omap_dma_chan(chan);
1241		unsigned req = *(unsigned *)param;
1242
1243		return req == c->dma_sig;
1244	}
1245	return false;
1246}
1247EXPORT_SYMBOL_GPL(omap_dma_filter_fn);
1248
1249static int omap_dma_init(void)
1250{
1251	return platform_driver_register(&omap_dma_driver);
1252}
1253subsys_initcall(omap_dma_init);
1254
1255static void __exit omap_dma_exit(void)
1256{
1257	platform_driver_unregister(&omap_dma_driver);
1258}
1259module_exit(omap_dma_exit);
1260
1261MODULE_AUTHOR("Russell King");
1262MODULE_LICENSE("GPL");