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v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright 2012 Marvell International Ltd.
   4 */
   5
   6#include <linux/err.h>
   7#include <linux/module.h>
   8#include <linux/init.h>
   9#include <linux/types.h>
  10#include <linux/interrupt.h>
  11#include <linux/dma-mapping.h>
  12#include <linux/slab.h>
  13#include <linux/dmaengine.h>
  14#include <linux/platform_device.h>
  15#include <linux/device.h>
  16#include <linux/platform_data/mmp_dma.h>
  17#include <linux/dmapool.h>
  18#include <linux/of_device.h>
  19#include <linux/of_dma.h>
  20#include <linux/of.h>
  21#include <linux/dma/mmp-pdma.h>
  22
  23#include "dmaengine.h"
  24
  25#define DCSR		0x0000
  26#define DALGN		0x00a0
  27#define DINT		0x00f0
  28#define DDADR		0x0200
  29#define DSADR(n)	(0x0204 + ((n) << 4))
  30#define DTADR(n)	(0x0208 + ((n) << 4))
  31#define DCMD		0x020c
  32
  33#define DCSR_RUN	BIT(31)	/* Run Bit (read / write) */
  34#define DCSR_NODESC	BIT(30)	/* No-Descriptor Fetch (read / write) */
  35#define DCSR_STOPIRQEN	BIT(29)	/* Stop Interrupt Enable (read / write) */
  36#define DCSR_REQPEND	BIT(8)	/* Request Pending (read-only) */
  37#define DCSR_STOPSTATE	BIT(3)	/* Stop State (read-only) */
  38#define DCSR_ENDINTR	BIT(2)	/* End Interrupt (read / write) */
  39#define DCSR_STARTINTR	BIT(1)	/* Start Interrupt (read / write) */
  40#define DCSR_BUSERR	BIT(0)	/* Bus Error Interrupt (read / write) */
  41
  42#define DCSR_EORIRQEN	BIT(28)	/* End of Receive Interrupt Enable (R/W) */
  43#define DCSR_EORJMPEN	BIT(27)	/* Jump to next descriptor on EOR */
  44#define DCSR_EORSTOPEN	BIT(26)	/* STOP on an EOR */
  45#define DCSR_SETCMPST	BIT(25)	/* Set Descriptor Compare Status */
  46#define DCSR_CLRCMPST	BIT(24)	/* Clear Descriptor Compare Status */
  47#define DCSR_CMPST	BIT(10)	/* The Descriptor Compare Status */
  48#define DCSR_EORINTR	BIT(9)	/* The end of Receive */
  49
  50#define DRCMR(n)	((((n) < 64) ? 0x0100 : 0x1100) + (((n) & 0x3f) << 2))
  51#define DRCMR_MAPVLD	BIT(7)	/* Map Valid (read / write) */
  52#define DRCMR_CHLNUM	0x1f	/* mask for Channel Number (read / write) */
  53
  54#define DDADR_DESCADDR	0xfffffff0	/* Address of next descriptor (mask) */
  55#define DDADR_STOP	BIT(0)	/* Stop (read / write) */
  56
  57#define DCMD_INCSRCADDR	BIT(31)	/* Source Address Increment Setting. */
  58#define DCMD_INCTRGADDR	BIT(30)	/* Target Address Increment Setting. */
  59#define DCMD_FLOWSRC	BIT(29)	/* Flow Control by the source. */
  60#define DCMD_FLOWTRG	BIT(28)	/* Flow Control by the target. */
  61#define DCMD_STARTIRQEN	BIT(22)	/* Start Interrupt Enable */
  62#define DCMD_ENDIRQEN	BIT(21)	/* End Interrupt Enable */
  63#define DCMD_ENDIAN	BIT(18)	/* Device Endian-ness. */
  64#define DCMD_BURST8	(1 << 16)	/* 8 byte burst */
  65#define DCMD_BURST16	(2 << 16)	/* 16 byte burst */
  66#define DCMD_BURST32	(3 << 16)	/* 32 byte burst */
  67#define DCMD_WIDTH1	(1 << 14)	/* 1 byte width */
  68#define DCMD_WIDTH2	(2 << 14)	/* 2 byte width (HalfWord) */
  69#define DCMD_WIDTH4	(3 << 14)	/* 4 byte width (Word) */
  70#define DCMD_LENGTH	0x01fff		/* length mask (max = 8K - 1) */
  71
  72#define PDMA_MAX_DESC_BYTES	DCMD_LENGTH
  73
  74struct mmp_pdma_desc_hw {
  75	u32 ddadr;	/* Points to the next descriptor + flags */
  76	u32 dsadr;	/* DSADR value for the current transfer */
  77	u32 dtadr;	/* DTADR value for the current transfer */
  78	u32 dcmd;	/* DCMD value for the current transfer */
  79} __aligned(32);
  80
  81struct mmp_pdma_desc_sw {
  82	struct mmp_pdma_desc_hw desc;
  83	struct list_head node;
  84	struct list_head tx_list;
  85	struct dma_async_tx_descriptor async_tx;
  86};
  87
  88struct mmp_pdma_phy;
  89
  90struct mmp_pdma_chan {
  91	struct device *dev;
  92	struct dma_chan chan;
  93	struct dma_async_tx_descriptor desc;
  94	struct mmp_pdma_phy *phy;
  95	enum dma_transfer_direction dir;
  96	struct dma_slave_config slave_config;
  97
  98	struct mmp_pdma_desc_sw *cyclic_first;	/* first desc_sw if channel
  99						 * is in cyclic mode */
 100
 101	/* channel's basic info */
 102	struct tasklet_struct tasklet;
 103	u32 dcmd;
 104	u32 drcmr;
 105	u32 dev_addr;
 106
 107	/* list for desc */
 108	spinlock_t desc_lock;		/* Descriptor list lock */
 109	struct list_head chain_pending;	/* Link descriptors queue for pending */
 110	struct list_head chain_running;	/* Link descriptors queue for running */
 111	bool idle;			/* channel statue machine */
 112	bool byte_align;
 113
 114	struct dma_pool *desc_pool;	/* Descriptors pool */
 115};
 116
 117struct mmp_pdma_phy {
 118	int idx;
 119	void __iomem *base;
 120	struct mmp_pdma_chan *vchan;
 121};
 122
 123struct mmp_pdma_device {
 124	int				dma_channels;
 125	void __iomem			*base;
 126	struct device			*dev;
 127	struct dma_device		device;
 128	struct mmp_pdma_phy		*phy;
 129	spinlock_t phy_lock; /* protect alloc/free phy channels */
 130};
 131
 132#define tx_to_mmp_pdma_desc(tx)					\
 133	container_of(tx, struct mmp_pdma_desc_sw, async_tx)
 134#define to_mmp_pdma_desc(lh)					\
 135	container_of(lh, struct mmp_pdma_desc_sw, node)
 136#define to_mmp_pdma_chan(dchan)					\
 137	container_of(dchan, struct mmp_pdma_chan, chan)
 138#define to_mmp_pdma_dev(dmadev)					\
 139	container_of(dmadev, struct mmp_pdma_device, device)
 140
 141static int mmp_pdma_config_write(struct dma_chan *dchan,
 142			   struct dma_slave_config *cfg,
 143			   enum dma_transfer_direction direction);
 144
 145static void set_desc(struct mmp_pdma_phy *phy, dma_addr_t addr)
 146{
 147	u32 reg = (phy->idx << 4) + DDADR;
 148
 149	writel(addr, phy->base + reg);
 150}
 151
 152static void enable_chan(struct mmp_pdma_phy *phy)
 153{
 154	u32 reg, dalgn;
 155
 156	if (!phy->vchan)
 157		return;
 158
 159	reg = DRCMR(phy->vchan->drcmr);
 160	writel(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 161
 162	dalgn = readl(phy->base + DALGN);
 163	if (phy->vchan->byte_align)
 164		dalgn |= 1 << phy->idx;
 165	else
 166		dalgn &= ~(1 << phy->idx);
 167	writel(dalgn, phy->base + DALGN);
 168
 169	reg = (phy->idx << 2) + DCSR;
 170	writel(readl(phy->base + reg) | DCSR_RUN, phy->base + reg);
 171}
 172
 173static void disable_chan(struct mmp_pdma_phy *phy)
 174{
 175	u32 reg;
 176
 177	if (!phy)
 178		return;
 179
 180	reg = (phy->idx << 2) + DCSR;
 181	writel(readl(phy->base + reg) & ~DCSR_RUN, phy->base + reg);
 182}
 183
 184static int clear_chan_irq(struct mmp_pdma_phy *phy)
 185{
 186	u32 dcsr;
 187	u32 dint = readl(phy->base + DINT);
 188	u32 reg = (phy->idx << 2) + DCSR;
 189
 190	if (!(dint & BIT(phy->idx)))
 191		return -EAGAIN;
 192
 193	/* clear irq */
 194	dcsr = readl(phy->base + reg);
 195	writel(dcsr, phy->base + reg);
 196	if ((dcsr & DCSR_BUSERR) && (phy->vchan))
 197		dev_warn(phy->vchan->dev, "DCSR_BUSERR\n");
 198
 199	return 0;
 200}
 201
 202static irqreturn_t mmp_pdma_chan_handler(int irq, void *dev_id)
 203{
 204	struct mmp_pdma_phy *phy = dev_id;
 205
 206	if (clear_chan_irq(phy) != 0)
 207		return IRQ_NONE;
 208
 209	tasklet_schedule(&phy->vchan->tasklet);
 210	return IRQ_HANDLED;
 211}
 212
 213static irqreturn_t mmp_pdma_int_handler(int irq, void *dev_id)
 214{
 215	struct mmp_pdma_device *pdev = dev_id;
 216	struct mmp_pdma_phy *phy;
 217	u32 dint = readl(pdev->base + DINT);
 218	int i, ret;
 219	int irq_num = 0;
 220
 221	while (dint) {
 222		i = __ffs(dint);
 223		/* only handle interrupts belonging to pdma driver*/
 224		if (i >= pdev->dma_channels)
 225			break;
 226		dint &= (dint - 1);
 227		phy = &pdev->phy[i];
 228		ret = mmp_pdma_chan_handler(irq, phy);
 229		if (ret == IRQ_HANDLED)
 230			irq_num++;
 231	}
 232
 233	if (irq_num)
 234		return IRQ_HANDLED;
 235
 236	return IRQ_NONE;
 237}
 238
 239/* lookup free phy channel as descending priority */
 240static struct mmp_pdma_phy *lookup_phy(struct mmp_pdma_chan *pchan)
 241{
 242	int prio, i;
 243	struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
 244	struct mmp_pdma_phy *phy, *found = NULL;
 245	unsigned long flags;
 246
 247	/*
 248	 * dma channel priorities
 249	 * ch 0 - 3,  16 - 19  <--> (0)
 250	 * ch 4 - 7,  20 - 23  <--> (1)
 251	 * ch 8 - 11, 24 - 27  <--> (2)
 252	 * ch 12 - 15, 28 - 31  <--> (3)
 253	 */
 254
 255	spin_lock_irqsave(&pdev->phy_lock, flags);
 256	for (prio = 0; prio <= ((pdev->dma_channels - 1) & 0xf) >> 2; prio++) {
 257		for (i = 0; i < pdev->dma_channels; i++) {
 258			if (prio != (i & 0xf) >> 2)
 259				continue;
 260			phy = &pdev->phy[i];
 261			if (!phy->vchan) {
 262				phy->vchan = pchan;
 263				found = phy;
 264				goto out_unlock;
 265			}
 266		}
 267	}
 268
 269out_unlock:
 270	spin_unlock_irqrestore(&pdev->phy_lock, flags);
 271	return found;
 272}
 273
 274static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan)
 275{
 276	struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
 277	unsigned long flags;
 278	u32 reg;
 279
 280	if (!pchan->phy)
 281		return;
 282
 283	/* clear the channel mapping in DRCMR */
 284	reg = DRCMR(pchan->drcmr);
 285	writel(0, pchan->phy->base + reg);
 286
 287	spin_lock_irqsave(&pdev->phy_lock, flags);
 288	pchan->phy->vchan = NULL;
 289	pchan->phy = NULL;
 290	spin_unlock_irqrestore(&pdev->phy_lock, flags);
 291}
 292
 293/*
 294 * start_pending_queue - transfer any pending transactions
 295 * pending list ==> running list
 296 */
 297static void start_pending_queue(struct mmp_pdma_chan *chan)
 298{
 299	struct mmp_pdma_desc_sw *desc;
 300
 301	/* still in running, irq will start the pending list */
 302	if (!chan->idle) {
 303		dev_dbg(chan->dev, "DMA controller still busy\n");
 304		return;
 305	}
 306
 307	if (list_empty(&chan->chain_pending)) {
 308		/* chance to re-fetch phy channel with higher prio */
 309		mmp_pdma_free_phy(chan);
 310		dev_dbg(chan->dev, "no pending list\n");
 311		return;
 312	}
 313
 314	if (!chan->phy) {
 315		chan->phy = lookup_phy(chan);
 316		if (!chan->phy) {
 317			dev_dbg(chan->dev, "no free dma channel\n");
 318			return;
 319		}
 320	}
 321
 322	/*
 323	 * pending -> running
 324	 * reintilize pending list
 325	 */
 326	desc = list_first_entry(&chan->chain_pending,
 327				struct mmp_pdma_desc_sw, node);
 328	list_splice_tail_init(&chan->chain_pending, &chan->chain_running);
 329
 330	/*
 331	 * Program the descriptor's address into the DMA controller,
 332	 * then start the DMA transaction
 333	 */
 334	set_desc(chan->phy, desc->async_tx.phys);
 335	enable_chan(chan->phy);
 336	chan->idle = false;
 337}
 338
 339
 340/* desc->tx_list ==> pending list */
 341static dma_cookie_t mmp_pdma_tx_submit(struct dma_async_tx_descriptor *tx)
 342{
 343	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(tx->chan);
 344	struct mmp_pdma_desc_sw *desc = tx_to_mmp_pdma_desc(tx);
 345	struct mmp_pdma_desc_sw *child;
 346	unsigned long flags;
 347	dma_cookie_t cookie = -EBUSY;
 348
 349	spin_lock_irqsave(&chan->desc_lock, flags);
 350
 351	list_for_each_entry(child, &desc->tx_list, node) {
 352		cookie = dma_cookie_assign(&child->async_tx);
 353	}
 354
 355	/* softly link to pending list - desc->tx_list ==> pending list */
 356	list_splice_tail_init(&desc->tx_list, &chan->chain_pending);
 357
 358	spin_unlock_irqrestore(&chan->desc_lock, flags);
 359
 360	return cookie;
 361}
 362
 363static struct mmp_pdma_desc_sw *
 364mmp_pdma_alloc_descriptor(struct mmp_pdma_chan *chan)
 365{
 366	struct mmp_pdma_desc_sw *desc;
 367	dma_addr_t pdesc;
 368
 369	desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &pdesc);
 370	if (!desc) {
 371		dev_err(chan->dev, "out of memory for link descriptor\n");
 372		return NULL;
 373	}
 374
 375	INIT_LIST_HEAD(&desc->tx_list);
 376	dma_async_tx_descriptor_init(&desc->async_tx, &chan->chan);
 377	/* each desc has submit */
 378	desc->async_tx.tx_submit = mmp_pdma_tx_submit;
 379	desc->async_tx.phys = pdesc;
 380
 381	return desc;
 382}
 383
 384/*
 385 * mmp_pdma_alloc_chan_resources - Allocate resources for DMA channel.
 386 *
 387 * This function will create a dma pool for descriptor allocation.
 388 * Request irq only when channel is requested
 389 * Return - The number of allocated descriptors.
 390 */
 391
 392static int mmp_pdma_alloc_chan_resources(struct dma_chan *dchan)
 393{
 394	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 395
 396	if (chan->desc_pool)
 397		return 1;
 398
 399	chan->desc_pool = dma_pool_create(dev_name(&dchan->dev->device),
 400					  chan->dev,
 401					  sizeof(struct mmp_pdma_desc_sw),
 402					  __alignof__(struct mmp_pdma_desc_sw),
 403					  0);
 404	if (!chan->desc_pool) {
 405		dev_err(chan->dev, "unable to allocate descriptor pool\n");
 406		return -ENOMEM;
 407	}
 408
 409	mmp_pdma_free_phy(chan);
 410	chan->idle = true;
 411	chan->dev_addr = 0;
 412	return 1;
 413}
 414
 415static void mmp_pdma_free_desc_list(struct mmp_pdma_chan *chan,
 416				    struct list_head *list)
 417{
 418	struct mmp_pdma_desc_sw *desc, *_desc;
 419
 420	list_for_each_entry_safe(desc, _desc, list, node) {
 421		list_del(&desc->node);
 422		dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
 423	}
 424}
 425
 426static void mmp_pdma_free_chan_resources(struct dma_chan *dchan)
 427{
 428	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 429	unsigned long flags;
 430
 431	spin_lock_irqsave(&chan->desc_lock, flags);
 432	mmp_pdma_free_desc_list(chan, &chan->chain_pending);
 433	mmp_pdma_free_desc_list(chan, &chan->chain_running);
 434	spin_unlock_irqrestore(&chan->desc_lock, flags);
 435
 436	dma_pool_destroy(chan->desc_pool);
 437	chan->desc_pool = NULL;
 438	chan->idle = true;
 439	chan->dev_addr = 0;
 440	mmp_pdma_free_phy(chan);
 441	return;
 442}
 443
 444static struct dma_async_tx_descriptor *
 445mmp_pdma_prep_memcpy(struct dma_chan *dchan,
 446		     dma_addr_t dma_dst, dma_addr_t dma_src,
 447		     size_t len, unsigned long flags)
 448{
 449	struct mmp_pdma_chan *chan;
 450	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
 451	size_t copy = 0;
 452
 453	if (!dchan)
 454		return NULL;
 455
 456	if (!len)
 457		return NULL;
 458
 459	chan = to_mmp_pdma_chan(dchan);
 460	chan->byte_align = false;
 461
 462	if (!chan->dir) {
 463		chan->dir = DMA_MEM_TO_MEM;
 464		chan->dcmd = DCMD_INCTRGADDR | DCMD_INCSRCADDR;
 465		chan->dcmd |= DCMD_BURST32;
 466	}
 467
 468	do {
 469		/* Allocate the link descriptor from DMA pool */
 470		new = mmp_pdma_alloc_descriptor(chan);
 471		if (!new) {
 472			dev_err(chan->dev, "no memory for desc\n");
 473			goto fail;
 474		}
 475
 476		copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
 477		if (dma_src & 0x7 || dma_dst & 0x7)
 478			chan->byte_align = true;
 479
 480		new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & copy);
 481		new->desc.dsadr = dma_src;
 482		new->desc.dtadr = dma_dst;
 483
 484		if (!first)
 485			first = new;
 486		else
 487			prev->desc.ddadr = new->async_tx.phys;
 488
 489		new->async_tx.cookie = 0;
 490		async_tx_ack(&new->async_tx);
 491
 492		prev = new;
 493		len -= copy;
 494
 495		if (chan->dir == DMA_MEM_TO_DEV) {
 496			dma_src += copy;
 497		} else if (chan->dir == DMA_DEV_TO_MEM) {
 498			dma_dst += copy;
 499		} else if (chan->dir == DMA_MEM_TO_MEM) {
 500			dma_src += copy;
 501			dma_dst += copy;
 502		}
 503
 504		/* Insert the link descriptor to the LD ring */
 505		list_add_tail(&new->node, &first->tx_list);
 506	} while (len);
 507
 508	first->async_tx.flags = flags; /* client is in control of this ack */
 509	first->async_tx.cookie = -EBUSY;
 510
 511	/* last desc and fire IRQ */
 512	new->desc.ddadr = DDADR_STOP;
 513	new->desc.dcmd |= DCMD_ENDIRQEN;
 514
 515	chan->cyclic_first = NULL;
 516
 517	return &first->async_tx;
 518
 519fail:
 520	if (first)
 521		mmp_pdma_free_desc_list(chan, &first->tx_list);
 522	return NULL;
 523}
 524
 525static struct dma_async_tx_descriptor *
 526mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
 527		       unsigned int sg_len, enum dma_transfer_direction dir,
 528		       unsigned long flags, void *context)
 529{
 530	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 531	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new = NULL;
 532	size_t len, avail;
 533	struct scatterlist *sg;
 534	dma_addr_t addr;
 535	int i;
 536
 537	if ((sgl == NULL) || (sg_len == 0))
 538		return NULL;
 539
 540	chan->byte_align = false;
 541
 542	mmp_pdma_config_write(dchan, &chan->slave_config, dir);
 543
 544	for_each_sg(sgl, sg, sg_len, i) {
 545		addr = sg_dma_address(sg);
 546		avail = sg_dma_len(sgl);
 547
 548		do {
 549			len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
 550			if (addr & 0x7)
 551				chan->byte_align = true;
 552
 553			/* allocate and populate the descriptor */
 554			new = mmp_pdma_alloc_descriptor(chan);
 555			if (!new) {
 556				dev_err(chan->dev, "no memory for desc\n");
 557				goto fail;
 558			}
 559
 560			new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & len);
 561			if (dir == DMA_MEM_TO_DEV) {
 562				new->desc.dsadr = addr;
 563				new->desc.dtadr = chan->dev_addr;
 564			} else {
 565				new->desc.dsadr = chan->dev_addr;
 566				new->desc.dtadr = addr;
 567			}
 568
 569			if (!first)
 570				first = new;
 571			else
 572				prev->desc.ddadr = new->async_tx.phys;
 573
 574			new->async_tx.cookie = 0;
 575			async_tx_ack(&new->async_tx);
 576			prev = new;
 577
 578			/* Insert the link descriptor to the LD ring */
 579			list_add_tail(&new->node, &first->tx_list);
 580
 581			/* update metadata */
 582			addr += len;
 583			avail -= len;
 584		} while (avail);
 585	}
 586
 587	first->async_tx.cookie = -EBUSY;
 588	first->async_tx.flags = flags;
 589
 590	/* last desc and fire IRQ */
 591	new->desc.ddadr = DDADR_STOP;
 592	new->desc.dcmd |= DCMD_ENDIRQEN;
 593
 594	chan->dir = dir;
 595	chan->cyclic_first = NULL;
 596
 597	return &first->async_tx;
 598
 599fail:
 600	if (first)
 601		mmp_pdma_free_desc_list(chan, &first->tx_list);
 602	return NULL;
 603}
 604
 605static struct dma_async_tx_descriptor *
 606mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan,
 607			 dma_addr_t buf_addr, size_t len, size_t period_len,
 608			 enum dma_transfer_direction direction,
 609			 unsigned long flags)
 610{
 611	struct mmp_pdma_chan *chan;
 612	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
 613	dma_addr_t dma_src, dma_dst;
 614
 615	if (!dchan || !len || !period_len)
 616		return NULL;
 617
 618	/* the buffer length must be a multiple of period_len */
 619	if (len % period_len != 0)
 620		return NULL;
 621
 622	if (period_len > PDMA_MAX_DESC_BYTES)
 623		return NULL;
 624
 625	chan = to_mmp_pdma_chan(dchan);
 626	mmp_pdma_config_write(dchan, &chan->slave_config, direction);
 627
 628	switch (direction) {
 629	case DMA_MEM_TO_DEV:
 630		dma_src = buf_addr;
 631		dma_dst = chan->dev_addr;
 632		break;
 633	case DMA_DEV_TO_MEM:
 634		dma_dst = buf_addr;
 635		dma_src = chan->dev_addr;
 636		break;
 637	default:
 638		dev_err(chan->dev, "Unsupported direction for cyclic DMA\n");
 639		return NULL;
 640	}
 641
 642	chan->dir = direction;
 643
 644	do {
 645		/* Allocate the link descriptor from DMA pool */
 646		new = mmp_pdma_alloc_descriptor(chan);
 647		if (!new) {
 648			dev_err(chan->dev, "no memory for desc\n");
 649			goto fail;
 650		}
 651
 652		new->desc.dcmd = (chan->dcmd | DCMD_ENDIRQEN |
 653				  (DCMD_LENGTH & period_len));
 654		new->desc.dsadr = dma_src;
 655		new->desc.dtadr = dma_dst;
 656
 657		if (!first)
 658			first = new;
 659		else
 660			prev->desc.ddadr = new->async_tx.phys;
 661
 662		new->async_tx.cookie = 0;
 663		async_tx_ack(&new->async_tx);
 664
 665		prev = new;
 666		len -= period_len;
 667
 668		if (chan->dir == DMA_MEM_TO_DEV)
 669			dma_src += period_len;
 670		else
 671			dma_dst += period_len;
 672
 673		/* Insert the link descriptor to the LD ring */
 674		list_add_tail(&new->node, &first->tx_list);
 675	} while (len);
 676
 677	first->async_tx.flags = flags; /* client is in control of this ack */
 678	first->async_tx.cookie = -EBUSY;
 679
 680	/* make the cyclic link */
 681	new->desc.ddadr = first->async_tx.phys;
 682	chan->cyclic_first = first;
 683
 684	return &first->async_tx;
 685
 686fail:
 687	if (first)
 688		mmp_pdma_free_desc_list(chan, &first->tx_list);
 689	return NULL;
 690}
 691
 692static int mmp_pdma_config_write(struct dma_chan *dchan,
 693			   struct dma_slave_config *cfg,
 694			   enum dma_transfer_direction direction)
 695{
 696	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 697	u32 maxburst = 0, addr = 0;
 698	enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 699
 700	if (!dchan)
 701		return -EINVAL;
 702
 703	if (direction == DMA_DEV_TO_MEM) {
 704		chan->dcmd = DCMD_INCTRGADDR | DCMD_FLOWSRC;
 705		maxburst = cfg->src_maxburst;
 706		width = cfg->src_addr_width;
 707		addr = cfg->src_addr;
 708	} else if (direction == DMA_MEM_TO_DEV) {
 709		chan->dcmd = DCMD_INCSRCADDR | DCMD_FLOWTRG;
 710		maxburst = cfg->dst_maxburst;
 711		width = cfg->dst_addr_width;
 712		addr = cfg->dst_addr;
 713	}
 714
 715	if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
 716		chan->dcmd |= DCMD_WIDTH1;
 717	else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
 718		chan->dcmd |= DCMD_WIDTH2;
 719	else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
 720		chan->dcmd |= DCMD_WIDTH4;
 721
 722	if (maxburst == 8)
 723		chan->dcmd |= DCMD_BURST8;
 724	else if (maxburst == 16)
 725		chan->dcmd |= DCMD_BURST16;
 726	else if (maxburst == 32)
 727		chan->dcmd |= DCMD_BURST32;
 728
 729	chan->dir = direction;
 730	chan->dev_addr = addr;
 731	/* FIXME: drivers should be ported over to use the filter
 732	 * function. Once that's done, the following two lines can
 733	 * be removed.
 734	 */
 735	if (cfg->slave_id)
 736		chan->drcmr = cfg->slave_id;
 737
 738	return 0;
 739}
 740
 741static int mmp_pdma_config(struct dma_chan *dchan,
 742			   struct dma_slave_config *cfg)
 743{
 744	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 745
 746	memcpy(&chan->slave_config, cfg, sizeof(*cfg));
 747	return 0;
 748}
 749
 750static int mmp_pdma_terminate_all(struct dma_chan *dchan)
 751{
 752	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 753	unsigned long flags;
 754
 755	if (!dchan)
 756		return -EINVAL;
 757
 758	disable_chan(chan->phy);
 759	mmp_pdma_free_phy(chan);
 760	spin_lock_irqsave(&chan->desc_lock, flags);
 761	mmp_pdma_free_desc_list(chan, &chan->chain_pending);
 762	mmp_pdma_free_desc_list(chan, &chan->chain_running);
 763	spin_unlock_irqrestore(&chan->desc_lock, flags);
 764	chan->idle = true;
 765
 766	return 0;
 767}
 768
 769static unsigned int mmp_pdma_residue(struct mmp_pdma_chan *chan,
 770				     dma_cookie_t cookie)
 771{
 772	struct mmp_pdma_desc_sw *sw;
 773	u32 curr, residue = 0;
 774	bool passed = false;
 775	bool cyclic = chan->cyclic_first != NULL;
 776
 777	/*
 778	 * If the channel does not have a phy pointer anymore, it has already
 779	 * been completed. Therefore, its residue is 0.
 780	 */
 781	if (!chan->phy)
 782		return 0;
 783
 784	if (chan->dir == DMA_DEV_TO_MEM)
 785		curr = readl(chan->phy->base + DTADR(chan->phy->idx));
 786	else
 787		curr = readl(chan->phy->base + DSADR(chan->phy->idx));
 788
 789	list_for_each_entry(sw, &chan->chain_running, node) {
 790		u32 start, end, len;
 791
 792		if (chan->dir == DMA_DEV_TO_MEM)
 793			start = sw->desc.dtadr;
 794		else
 795			start = sw->desc.dsadr;
 796
 797		len = sw->desc.dcmd & DCMD_LENGTH;
 798		end = start + len;
 799
 800		/*
 801		 * 'passed' will be latched once we found the descriptor which
 802		 * lies inside the boundaries of the curr pointer. All
 803		 * descriptors that occur in the list _after_ we found that
 804		 * partially handled descriptor are still to be processed and
 805		 * are hence added to the residual bytes counter.
 806		 */
 807
 808		if (passed) {
 809			residue += len;
 810		} else if (curr >= start && curr <= end) {
 811			residue += end - curr;
 812			passed = true;
 813		}
 814
 815		/*
 816		 * Descriptors that have the ENDIRQEN bit set mark the end of a
 817		 * transaction chain, and the cookie assigned with it has been
 818		 * returned previously from mmp_pdma_tx_submit().
 819		 *
 820		 * In case we have multiple transactions in the running chain,
 821		 * and the cookie does not match the one the user asked us
 822		 * about, reset the state variables and start over.
 823		 *
 824		 * This logic does not apply to cyclic transactions, where all
 825		 * descriptors have the ENDIRQEN bit set, and for which we
 826		 * can't have multiple transactions on one channel anyway.
 827		 */
 828		if (cyclic || !(sw->desc.dcmd & DCMD_ENDIRQEN))
 829			continue;
 830
 831		if (sw->async_tx.cookie == cookie) {
 832			return residue;
 833		} else {
 834			residue = 0;
 835			passed = false;
 836		}
 837	}
 838
 839	/* We should only get here in case of cyclic transactions */
 840	return residue;
 841}
 842
 843static enum dma_status mmp_pdma_tx_status(struct dma_chan *dchan,
 844					  dma_cookie_t cookie,
 845					  struct dma_tx_state *txstate)
 846{
 847	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 848	enum dma_status ret;
 849
 850	ret = dma_cookie_status(dchan, cookie, txstate);
 851	if (likely(ret != DMA_ERROR))
 852		dma_set_residue(txstate, mmp_pdma_residue(chan, cookie));
 853
 854	return ret;
 855}
 856
 857/*
 858 * mmp_pdma_issue_pending - Issue the DMA start command
 859 * pending list ==> running list
 860 */
 861static void mmp_pdma_issue_pending(struct dma_chan *dchan)
 862{
 863	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 864	unsigned long flags;
 865
 866	spin_lock_irqsave(&chan->desc_lock, flags);
 867	start_pending_queue(chan);
 868	spin_unlock_irqrestore(&chan->desc_lock, flags);
 869}
 870
 871/*
 872 * dma_do_tasklet
 873 * Do call back
 874 * Start pending list
 875 */
 876static void dma_do_tasklet(unsigned long data)
 877{
 878	struct mmp_pdma_chan *chan = (struct mmp_pdma_chan *)data;
 879	struct mmp_pdma_desc_sw *desc, *_desc;
 880	LIST_HEAD(chain_cleanup);
 881	unsigned long flags;
 882	struct dmaengine_desc_callback cb;
 883
 884	if (chan->cyclic_first) {
 885		spin_lock_irqsave(&chan->desc_lock, flags);
 886		desc = chan->cyclic_first;
 887		dmaengine_desc_get_callback(&desc->async_tx, &cb);
 888		spin_unlock_irqrestore(&chan->desc_lock, flags);
 889
 890		dmaengine_desc_callback_invoke(&cb, NULL);
 891
 892		return;
 893	}
 894
 895	/* submit pending list; callback for each desc; free desc */
 896	spin_lock_irqsave(&chan->desc_lock, flags);
 897
 898	list_for_each_entry_safe(desc, _desc, &chan->chain_running, node) {
 899		/*
 900		 * move the descriptors to a temporary list so we can drop
 901		 * the lock during the entire cleanup operation
 902		 */
 903		list_move(&desc->node, &chain_cleanup);
 904
 905		/*
 906		 * Look for the first list entry which has the ENDIRQEN flag
 907		 * set. That is the descriptor we got an interrupt for, so
 908		 * complete that transaction and its cookie.
 909		 */
 910		if (desc->desc.dcmd & DCMD_ENDIRQEN) {
 911			dma_cookie_t cookie = desc->async_tx.cookie;
 912			dma_cookie_complete(&desc->async_tx);
 913			dev_dbg(chan->dev, "completed_cookie=%d\n", cookie);
 914			break;
 915		}
 916	}
 917
 918	/*
 919	 * The hardware is idle and ready for more when the
 920	 * chain_running list is empty.
 921	 */
 922	chan->idle = list_empty(&chan->chain_running);
 923
 924	/* Start any pending transactions automatically */
 925	start_pending_queue(chan);
 926	spin_unlock_irqrestore(&chan->desc_lock, flags);
 927
 928	/* Run the callback for each descriptor, in order */
 929	list_for_each_entry_safe(desc, _desc, &chain_cleanup, node) {
 930		struct dma_async_tx_descriptor *txd = &desc->async_tx;
 931
 932		/* Remove from the list of transactions */
 933		list_del(&desc->node);
 934		/* Run the link descriptor callback function */
 935		dmaengine_desc_get_callback(txd, &cb);
 936		dmaengine_desc_callback_invoke(&cb, NULL);
 937
 938		dma_pool_free(chan->desc_pool, desc, txd->phys);
 939	}
 940}
 941
 942static int mmp_pdma_remove(struct platform_device *op)
 943{
 944	struct mmp_pdma_device *pdev = platform_get_drvdata(op);
 945	struct mmp_pdma_phy *phy;
 946	int i, irq = 0, irq_num = 0;
 947
 948	if (op->dev.of_node)
 949		of_dma_controller_free(op->dev.of_node);
 950
 951	for (i = 0; i < pdev->dma_channels; i++) {
 952		if (platform_get_irq(op, i) > 0)
 953			irq_num++;
 954	}
 955
 956	if (irq_num != pdev->dma_channels) {
 957		irq = platform_get_irq(op, 0);
 958		devm_free_irq(&op->dev, irq, pdev);
 959	} else {
 960		for (i = 0; i < pdev->dma_channels; i++) {
 961			phy = &pdev->phy[i];
 962			irq = platform_get_irq(op, i);
 963			devm_free_irq(&op->dev, irq, phy);
 964		}
 965	}
 966
 967	dma_async_device_unregister(&pdev->device);
 968	return 0;
 969}
 970
 971static int mmp_pdma_chan_init(struct mmp_pdma_device *pdev, int idx, int irq)
 972{
 973	struct mmp_pdma_phy *phy  = &pdev->phy[idx];
 974	struct mmp_pdma_chan *chan;
 975	int ret;
 976
 977	chan = devm_kzalloc(pdev->dev, sizeof(*chan), GFP_KERNEL);
 978	if (chan == NULL)
 979		return -ENOMEM;
 980
 981	phy->idx = idx;
 982	phy->base = pdev->base;
 983
 984	if (irq) {
 985		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_chan_handler,
 986				       IRQF_SHARED, "pdma", phy);
 987		if (ret) {
 988			dev_err(pdev->dev, "channel request irq fail!\n");
 989			return ret;
 990		}
 991	}
 992
 993	spin_lock_init(&chan->desc_lock);
 994	chan->dev = pdev->dev;
 995	chan->chan.device = &pdev->device;
 996	tasklet_init(&chan->tasklet, dma_do_tasklet, (unsigned long)chan);
 997	INIT_LIST_HEAD(&chan->chain_pending);
 998	INIT_LIST_HEAD(&chan->chain_running);
 999
1000	/* register virt channel to dma engine */
1001	list_add_tail(&chan->chan.device_node, &pdev->device.channels);
1002
1003	return 0;
1004}
1005
1006static const struct of_device_id mmp_pdma_dt_ids[] = {
1007	{ .compatible = "marvell,pdma-1.0", },
1008	{}
1009};
1010MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids);
1011
1012static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec,
1013					   struct of_dma *ofdma)
1014{
1015	struct mmp_pdma_device *d = ofdma->of_dma_data;
1016	struct dma_chan *chan;
1017
1018	chan = dma_get_any_slave_channel(&d->device);
1019	if (!chan)
1020		return NULL;
1021
1022	to_mmp_pdma_chan(chan)->drcmr = dma_spec->args[0];
1023
1024	return chan;
1025}
1026
1027static int mmp_pdma_probe(struct platform_device *op)
1028{
1029	struct mmp_pdma_device *pdev;
1030	const struct of_device_id *of_id;
1031	struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1032	struct resource *iores;
1033	int i, ret, irq = 0;
1034	int dma_channels = 0, irq_num = 0;
1035	const enum dma_slave_buswidth widths =
1036		DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1037		DMA_SLAVE_BUSWIDTH_4_BYTES;
1038
1039	pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1040	if (!pdev)
1041		return -ENOMEM;
1042
1043	pdev->dev = &op->dev;
1044
1045	spin_lock_init(&pdev->phy_lock);
1046
1047	iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1048	pdev->base = devm_ioremap_resource(pdev->dev, iores);
1049	if (IS_ERR(pdev->base))
1050		return PTR_ERR(pdev->base);
1051
1052	of_id = of_match_device(mmp_pdma_dt_ids, pdev->dev);
1053	if (of_id)
1054		of_property_read_u32(pdev->dev->of_node, "#dma-channels",
1055				     &dma_channels);
1056	else if (pdata && pdata->dma_channels)
1057		dma_channels = pdata->dma_channels;
1058	else
1059		dma_channels = 32;	/* default 32 channel */
1060	pdev->dma_channels = dma_channels;
1061
1062	for (i = 0; i < dma_channels; i++) {
1063		if (platform_get_irq_optional(op, i) > 0)
1064			irq_num++;
1065	}
1066
1067	pdev->phy = devm_kcalloc(pdev->dev, dma_channels, sizeof(*pdev->phy),
1068				 GFP_KERNEL);
1069	if (pdev->phy == NULL)
1070		return -ENOMEM;
1071
1072	INIT_LIST_HEAD(&pdev->device.channels);
1073
1074	if (irq_num != dma_channels) {
1075		/* all chan share one irq, demux inside */
1076		irq = platform_get_irq(op, 0);
1077		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_int_handler,
1078				       IRQF_SHARED, "pdma", pdev);
1079		if (ret)
1080			return ret;
1081	}
1082
1083	for (i = 0; i < dma_channels; i++) {
1084		irq = (irq_num != dma_channels) ? 0 : platform_get_irq(op, i);
1085		ret = mmp_pdma_chan_init(pdev, i, irq);
1086		if (ret)
1087			return ret;
1088	}
1089
1090	dma_cap_set(DMA_SLAVE, pdev->device.cap_mask);
1091	dma_cap_set(DMA_MEMCPY, pdev->device.cap_mask);
1092	dma_cap_set(DMA_CYCLIC, pdev->device.cap_mask);
1093	dma_cap_set(DMA_PRIVATE, pdev->device.cap_mask);
1094	pdev->device.dev = &op->dev;
1095	pdev->device.device_alloc_chan_resources = mmp_pdma_alloc_chan_resources;
1096	pdev->device.device_free_chan_resources = mmp_pdma_free_chan_resources;
1097	pdev->device.device_tx_status = mmp_pdma_tx_status;
1098	pdev->device.device_prep_dma_memcpy = mmp_pdma_prep_memcpy;
1099	pdev->device.device_prep_slave_sg = mmp_pdma_prep_slave_sg;
1100	pdev->device.device_prep_dma_cyclic = mmp_pdma_prep_dma_cyclic;
1101	pdev->device.device_issue_pending = mmp_pdma_issue_pending;
1102	pdev->device.device_config = mmp_pdma_config;
1103	pdev->device.device_terminate_all = mmp_pdma_terminate_all;
1104	pdev->device.copy_align = DMAENGINE_ALIGN_8_BYTES;
1105	pdev->device.src_addr_widths = widths;
1106	pdev->device.dst_addr_widths = widths;
1107	pdev->device.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1108	pdev->device.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1109
1110	if (pdev->dev->coherent_dma_mask)
1111		dma_set_mask(pdev->dev, pdev->dev->coherent_dma_mask);
1112	else
1113		dma_set_mask(pdev->dev, DMA_BIT_MASK(64));
1114
1115	ret = dma_async_device_register(&pdev->device);
1116	if (ret) {
1117		dev_err(pdev->device.dev, "unable to register\n");
1118		return ret;
1119	}
1120
1121	if (op->dev.of_node) {
1122		/* Device-tree DMA controller registration */
1123		ret = of_dma_controller_register(op->dev.of_node,
1124						 mmp_pdma_dma_xlate, pdev);
1125		if (ret < 0) {
1126			dev_err(&op->dev, "of_dma_controller_register failed\n");
1127			return ret;
1128		}
1129	}
1130
1131	platform_set_drvdata(op, pdev);
1132	dev_info(pdev->device.dev, "initialized %d channels\n", dma_channels);
1133	return 0;
1134}
1135
1136static const struct platform_device_id mmp_pdma_id_table[] = {
1137	{ "mmp-pdma", },
1138	{ },
1139};
1140
1141static struct platform_driver mmp_pdma_driver = {
1142	.driver		= {
1143		.name	= "mmp-pdma",
1144		.of_match_table = mmp_pdma_dt_ids,
1145	},
1146	.id_table	= mmp_pdma_id_table,
1147	.probe		= mmp_pdma_probe,
1148	.remove		= mmp_pdma_remove,
1149};
1150
1151bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param)
1152{
1153	struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan);
1154
1155	if (chan->device->dev->driver != &mmp_pdma_driver.driver)
1156		return false;
1157
1158	c->drcmr = *(unsigned int *)param;
1159
1160	return true;
1161}
1162EXPORT_SYMBOL_GPL(mmp_pdma_filter_fn);
1163
1164module_platform_driver(mmp_pdma_driver);
1165
1166MODULE_DESCRIPTION("MARVELL MMP Peripheral DMA Driver");
1167MODULE_AUTHOR("Marvell International Ltd.");
1168MODULE_LICENSE("GPL v2");
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright 2012 Marvell International Ltd.
   4 */
   5
   6#include <linux/err.h>
   7#include <linux/module.h>
   8#include <linux/init.h>
   9#include <linux/types.h>
  10#include <linux/interrupt.h>
  11#include <linux/dma-mapping.h>
  12#include <linux/slab.h>
  13#include <linux/dmaengine.h>
  14#include <linux/platform_device.h>
  15#include <linux/device.h>
  16#include <linux/platform_data/mmp_dma.h>
  17#include <linux/dmapool.h>
  18#include <linux/of_device.h>
  19#include <linux/of_dma.h>
  20#include <linux/of.h>
 
  21
  22#include "dmaengine.h"
  23
  24#define DCSR		0x0000
  25#define DALGN		0x00a0
  26#define DINT		0x00f0
  27#define DDADR		0x0200
  28#define DSADR(n)	(0x0204 + ((n) << 4))
  29#define DTADR(n)	(0x0208 + ((n) << 4))
  30#define DCMD		0x020c
  31
  32#define DCSR_RUN	BIT(31)	/* Run Bit (read / write) */
  33#define DCSR_NODESC	BIT(30)	/* No-Descriptor Fetch (read / write) */
  34#define DCSR_STOPIRQEN	BIT(29)	/* Stop Interrupt Enable (read / write) */
  35#define DCSR_REQPEND	BIT(8)	/* Request Pending (read-only) */
  36#define DCSR_STOPSTATE	BIT(3)	/* Stop State (read-only) */
  37#define DCSR_ENDINTR	BIT(2)	/* End Interrupt (read / write) */
  38#define DCSR_STARTINTR	BIT(1)	/* Start Interrupt (read / write) */
  39#define DCSR_BUSERR	BIT(0)	/* Bus Error Interrupt (read / write) */
  40
  41#define DCSR_EORIRQEN	BIT(28)	/* End of Receive Interrupt Enable (R/W) */
  42#define DCSR_EORJMPEN	BIT(27)	/* Jump to next descriptor on EOR */
  43#define DCSR_EORSTOPEN	BIT(26)	/* STOP on an EOR */
  44#define DCSR_SETCMPST	BIT(25)	/* Set Descriptor Compare Status */
  45#define DCSR_CLRCMPST	BIT(24)	/* Clear Descriptor Compare Status */
  46#define DCSR_CMPST	BIT(10)	/* The Descriptor Compare Status */
  47#define DCSR_EORINTR	BIT(9)	/* The end of Receive */
  48
  49#define DRCMR(n)	((((n) < 64) ? 0x0100 : 0x1100) + (((n) & 0x3f) << 2))
  50#define DRCMR_MAPVLD	BIT(7)	/* Map Valid (read / write) */
  51#define DRCMR_CHLNUM	0x1f	/* mask for Channel Number (read / write) */
  52
  53#define DDADR_DESCADDR	0xfffffff0	/* Address of next descriptor (mask) */
  54#define DDADR_STOP	BIT(0)	/* Stop (read / write) */
  55
  56#define DCMD_INCSRCADDR	BIT(31)	/* Source Address Increment Setting. */
  57#define DCMD_INCTRGADDR	BIT(30)	/* Target Address Increment Setting. */
  58#define DCMD_FLOWSRC	BIT(29)	/* Flow Control by the source. */
  59#define DCMD_FLOWTRG	BIT(28)	/* Flow Control by the target. */
  60#define DCMD_STARTIRQEN	BIT(22)	/* Start Interrupt Enable */
  61#define DCMD_ENDIRQEN	BIT(21)	/* End Interrupt Enable */
  62#define DCMD_ENDIAN	BIT(18)	/* Device Endian-ness. */
  63#define DCMD_BURST8	(1 << 16)	/* 8 byte burst */
  64#define DCMD_BURST16	(2 << 16)	/* 16 byte burst */
  65#define DCMD_BURST32	(3 << 16)	/* 32 byte burst */
  66#define DCMD_WIDTH1	(1 << 14)	/* 1 byte width */
  67#define DCMD_WIDTH2	(2 << 14)	/* 2 byte width (HalfWord) */
  68#define DCMD_WIDTH4	(3 << 14)	/* 4 byte width (Word) */
  69#define DCMD_LENGTH	0x01fff		/* length mask (max = 8K - 1) */
  70
  71#define PDMA_MAX_DESC_BYTES	DCMD_LENGTH
  72
  73struct mmp_pdma_desc_hw {
  74	u32 ddadr;	/* Points to the next descriptor + flags */
  75	u32 dsadr;	/* DSADR value for the current transfer */
  76	u32 dtadr;	/* DTADR value for the current transfer */
  77	u32 dcmd;	/* DCMD value for the current transfer */
  78} __aligned(32);
  79
  80struct mmp_pdma_desc_sw {
  81	struct mmp_pdma_desc_hw desc;
  82	struct list_head node;
  83	struct list_head tx_list;
  84	struct dma_async_tx_descriptor async_tx;
  85};
  86
  87struct mmp_pdma_phy;
  88
  89struct mmp_pdma_chan {
  90	struct device *dev;
  91	struct dma_chan chan;
  92	struct dma_async_tx_descriptor desc;
  93	struct mmp_pdma_phy *phy;
  94	enum dma_transfer_direction dir;
  95	struct dma_slave_config slave_config;
  96
  97	struct mmp_pdma_desc_sw *cyclic_first;	/* first desc_sw if channel
  98						 * is in cyclic mode */
  99
 100	/* channel's basic info */
 101	struct tasklet_struct tasklet;
 102	u32 dcmd;
 103	u32 drcmr;
 104	u32 dev_addr;
 105
 106	/* list for desc */
 107	spinlock_t desc_lock;		/* Descriptor list lock */
 108	struct list_head chain_pending;	/* Link descriptors queue for pending */
 109	struct list_head chain_running;	/* Link descriptors queue for running */
 110	bool idle;			/* channel statue machine */
 111	bool byte_align;
 112
 113	struct dma_pool *desc_pool;	/* Descriptors pool */
 114};
 115
 116struct mmp_pdma_phy {
 117	int idx;
 118	void __iomem *base;
 119	struct mmp_pdma_chan *vchan;
 120};
 121
 122struct mmp_pdma_device {
 123	int				dma_channels;
 124	void __iomem			*base;
 125	struct device			*dev;
 126	struct dma_device		device;
 127	struct mmp_pdma_phy		*phy;
 128	spinlock_t phy_lock; /* protect alloc/free phy channels */
 129};
 130
 131#define tx_to_mmp_pdma_desc(tx)					\
 132	container_of(tx, struct mmp_pdma_desc_sw, async_tx)
 133#define to_mmp_pdma_desc(lh)					\
 134	container_of(lh, struct mmp_pdma_desc_sw, node)
 135#define to_mmp_pdma_chan(dchan)					\
 136	container_of(dchan, struct mmp_pdma_chan, chan)
 137#define to_mmp_pdma_dev(dmadev)					\
 138	container_of(dmadev, struct mmp_pdma_device, device)
 139
 140static int mmp_pdma_config_write(struct dma_chan *dchan,
 141			   struct dma_slave_config *cfg,
 142			   enum dma_transfer_direction direction);
 143
 144static void set_desc(struct mmp_pdma_phy *phy, dma_addr_t addr)
 145{
 146	u32 reg = (phy->idx << 4) + DDADR;
 147
 148	writel(addr, phy->base + reg);
 149}
 150
 151static void enable_chan(struct mmp_pdma_phy *phy)
 152{
 153	u32 reg, dalgn;
 154
 155	if (!phy->vchan)
 156		return;
 157
 158	reg = DRCMR(phy->vchan->drcmr);
 159	writel(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 160
 161	dalgn = readl(phy->base + DALGN);
 162	if (phy->vchan->byte_align)
 163		dalgn |= 1 << phy->idx;
 164	else
 165		dalgn &= ~(1 << phy->idx);
 166	writel(dalgn, phy->base + DALGN);
 167
 168	reg = (phy->idx << 2) + DCSR;
 169	writel(readl(phy->base + reg) | DCSR_RUN, phy->base + reg);
 170}
 171
 172static void disable_chan(struct mmp_pdma_phy *phy)
 173{
 174	u32 reg;
 175
 176	if (!phy)
 177		return;
 178
 179	reg = (phy->idx << 2) + DCSR;
 180	writel(readl(phy->base + reg) & ~DCSR_RUN, phy->base + reg);
 181}
 182
 183static int clear_chan_irq(struct mmp_pdma_phy *phy)
 184{
 185	u32 dcsr;
 186	u32 dint = readl(phy->base + DINT);
 187	u32 reg = (phy->idx << 2) + DCSR;
 188
 189	if (!(dint & BIT(phy->idx)))
 190		return -EAGAIN;
 191
 192	/* clear irq */
 193	dcsr = readl(phy->base + reg);
 194	writel(dcsr, phy->base + reg);
 195	if ((dcsr & DCSR_BUSERR) && (phy->vchan))
 196		dev_warn(phy->vchan->dev, "DCSR_BUSERR\n");
 197
 198	return 0;
 199}
 200
 201static irqreturn_t mmp_pdma_chan_handler(int irq, void *dev_id)
 202{
 203	struct mmp_pdma_phy *phy = dev_id;
 204
 205	if (clear_chan_irq(phy) != 0)
 206		return IRQ_NONE;
 207
 208	tasklet_schedule(&phy->vchan->tasklet);
 209	return IRQ_HANDLED;
 210}
 211
 212static irqreturn_t mmp_pdma_int_handler(int irq, void *dev_id)
 213{
 214	struct mmp_pdma_device *pdev = dev_id;
 215	struct mmp_pdma_phy *phy;
 216	u32 dint = readl(pdev->base + DINT);
 217	int i, ret;
 218	int irq_num = 0;
 219
 220	while (dint) {
 221		i = __ffs(dint);
 222		/* only handle interrupts belonging to pdma driver*/
 223		if (i >= pdev->dma_channels)
 224			break;
 225		dint &= (dint - 1);
 226		phy = &pdev->phy[i];
 227		ret = mmp_pdma_chan_handler(irq, phy);
 228		if (ret == IRQ_HANDLED)
 229			irq_num++;
 230	}
 231
 232	if (irq_num)
 233		return IRQ_HANDLED;
 234
 235	return IRQ_NONE;
 236}
 237
 238/* lookup free phy channel as descending priority */
 239static struct mmp_pdma_phy *lookup_phy(struct mmp_pdma_chan *pchan)
 240{
 241	int prio, i;
 242	struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
 243	struct mmp_pdma_phy *phy, *found = NULL;
 244	unsigned long flags;
 245
 246	/*
 247	 * dma channel priorities
 248	 * ch 0 - 3,  16 - 19  <--> (0)
 249	 * ch 4 - 7,  20 - 23  <--> (1)
 250	 * ch 8 - 11, 24 - 27  <--> (2)
 251	 * ch 12 - 15, 28 - 31  <--> (3)
 252	 */
 253
 254	spin_lock_irqsave(&pdev->phy_lock, flags);
 255	for (prio = 0; prio <= ((pdev->dma_channels - 1) & 0xf) >> 2; prio++) {
 256		for (i = 0; i < pdev->dma_channels; i++) {
 257			if (prio != (i & 0xf) >> 2)
 258				continue;
 259			phy = &pdev->phy[i];
 260			if (!phy->vchan) {
 261				phy->vchan = pchan;
 262				found = phy;
 263				goto out_unlock;
 264			}
 265		}
 266	}
 267
 268out_unlock:
 269	spin_unlock_irqrestore(&pdev->phy_lock, flags);
 270	return found;
 271}
 272
 273static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan)
 274{
 275	struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
 276	unsigned long flags;
 277	u32 reg;
 278
 279	if (!pchan->phy)
 280		return;
 281
 282	/* clear the channel mapping in DRCMR */
 283	reg = DRCMR(pchan->drcmr);
 284	writel(0, pchan->phy->base + reg);
 285
 286	spin_lock_irqsave(&pdev->phy_lock, flags);
 287	pchan->phy->vchan = NULL;
 288	pchan->phy = NULL;
 289	spin_unlock_irqrestore(&pdev->phy_lock, flags);
 290}
 291
 292/*
 293 * start_pending_queue - transfer any pending transactions
 294 * pending list ==> running list
 295 */
 296static void start_pending_queue(struct mmp_pdma_chan *chan)
 297{
 298	struct mmp_pdma_desc_sw *desc;
 299
 300	/* still in running, irq will start the pending list */
 301	if (!chan->idle) {
 302		dev_dbg(chan->dev, "DMA controller still busy\n");
 303		return;
 304	}
 305
 306	if (list_empty(&chan->chain_pending)) {
 307		/* chance to re-fetch phy channel with higher prio */
 308		mmp_pdma_free_phy(chan);
 309		dev_dbg(chan->dev, "no pending list\n");
 310		return;
 311	}
 312
 313	if (!chan->phy) {
 314		chan->phy = lookup_phy(chan);
 315		if (!chan->phy) {
 316			dev_dbg(chan->dev, "no free dma channel\n");
 317			return;
 318		}
 319	}
 320
 321	/*
 322	 * pending -> running
 323	 * reintilize pending list
 324	 */
 325	desc = list_first_entry(&chan->chain_pending,
 326				struct mmp_pdma_desc_sw, node);
 327	list_splice_tail_init(&chan->chain_pending, &chan->chain_running);
 328
 329	/*
 330	 * Program the descriptor's address into the DMA controller,
 331	 * then start the DMA transaction
 332	 */
 333	set_desc(chan->phy, desc->async_tx.phys);
 334	enable_chan(chan->phy);
 335	chan->idle = false;
 336}
 337
 338
 339/* desc->tx_list ==> pending list */
 340static dma_cookie_t mmp_pdma_tx_submit(struct dma_async_tx_descriptor *tx)
 341{
 342	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(tx->chan);
 343	struct mmp_pdma_desc_sw *desc = tx_to_mmp_pdma_desc(tx);
 344	struct mmp_pdma_desc_sw *child;
 345	unsigned long flags;
 346	dma_cookie_t cookie = -EBUSY;
 347
 348	spin_lock_irqsave(&chan->desc_lock, flags);
 349
 350	list_for_each_entry(child, &desc->tx_list, node) {
 351		cookie = dma_cookie_assign(&child->async_tx);
 352	}
 353
 354	/* softly link to pending list - desc->tx_list ==> pending list */
 355	list_splice_tail_init(&desc->tx_list, &chan->chain_pending);
 356
 357	spin_unlock_irqrestore(&chan->desc_lock, flags);
 358
 359	return cookie;
 360}
 361
 362static struct mmp_pdma_desc_sw *
 363mmp_pdma_alloc_descriptor(struct mmp_pdma_chan *chan)
 364{
 365	struct mmp_pdma_desc_sw *desc;
 366	dma_addr_t pdesc;
 367
 368	desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &pdesc);
 369	if (!desc) {
 370		dev_err(chan->dev, "out of memory for link descriptor\n");
 371		return NULL;
 372	}
 373
 374	INIT_LIST_HEAD(&desc->tx_list);
 375	dma_async_tx_descriptor_init(&desc->async_tx, &chan->chan);
 376	/* each desc has submit */
 377	desc->async_tx.tx_submit = mmp_pdma_tx_submit;
 378	desc->async_tx.phys = pdesc;
 379
 380	return desc;
 381}
 382
 383/*
 384 * mmp_pdma_alloc_chan_resources - Allocate resources for DMA channel.
 385 *
 386 * This function will create a dma pool for descriptor allocation.
 387 * Request irq only when channel is requested
 388 * Return - The number of allocated descriptors.
 389 */
 390
 391static int mmp_pdma_alloc_chan_resources(struct dma_chan *dchan)
 392{
 393	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 394
 395	if (chan->desc_pool)
 396		return 1;
 397
 398	chan->desc_pool = dma_pool_create(dev_name(&dchan->dev->device),
 399					  chan->dev,
 400					  sizeof(struct mmp_pdma_desc_sw),
 401					  __alignof__(struct mmp_pdma_desc_sw),
 402					  0);
 403	if (!chan->desc_pool) {
 404		dev_err(chan->dev, "unable to allocate descriptor pool\n");
 405		return -ENOMEM;
 406	}
 407
 408	mmp_pdma_free_phy(chan);
 409	chan->idle = true;
 410	chan->dev_addr = 0;
 411	return 1;
 412}
 413
 414static void mmp_pdma_free_desc_list(struct mmp_pdma_chan *chan,
 415				    struct list_head *list)
 416{
 417	struct mmp_pdma_desc_sw *desc, *_desc;
 418
 419	list_for_each_entry_safe(desc, _desc, list, node) {
 420		list_del(&desc->node);
 421		dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
 422	}
 423}
 424
 425static void mmp_pdma_free_chan_resources(struct dma_chan *dchan)
 426{
 427	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 428	unsigned long flags;
 429
 430	spin_lock_irqsave(&chan->desc_lock, flags);
 431	mmp_pdma_free_desc_list(chan, &chan->chain_pending);
 432	mmp_pdma_free_desc_list(chan, &chan->chain_running);
 433	spin_unlock_irqrestore(&chan->desc_lock, flags);
 434
 435	dma_pool_destroy(chan->desc_pool);
 436	chan->desc_pool = NULL;
 437	chan->idle = true;
 438	chan->dev_addr = 0;
 439	mmp_pdma_free_phy(chan);
 440	return;
 441}
 442
 443static struct dma_async_tx_descriptor *
 444mmp_pdma_prep_memcpy(struct dma_chan *dchan,
 445		     dma_addr_t dma_dst, dma_addr_t dma_src,
 446		     size_t len, unsigned long flags)
 447{
 448	struct mmp_pdma_chan *chan;
 449	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
 450	size_t copy = 0;
 451
 452	if (!dchan)
 453		return NULL;
 454
 455	if (!len)
 456		return NULL;
 457
 458	chan = to_mmp_pdma_chan(dchan);
 459	chan->byte_align = false;
 460
 461	if (!chan->dir) {
 462		chan->dir = DMA_MEM_TO_MEM;
 463		chan->dcmd = DCMD_INCTRGADDR | DCMD_INCSRCADDR;
 464		chan->dcmd |= DCMD_BURST32;
 465	}
 466
 467	do {
 468		/* Allocate the link descriptor from DMA pool */
 469		new = mmp_pdma_alloc_descriptor(chan);
 470		if (!new) {
 471			dev_err(chan->dev, "no memory for desc\n");
 472			goto fail;
 473		}
 474
 475		copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
 476		if (dma_src & 0x7 || dma_dst & 0x7)
 477			chan->byte_align = true;
 478
 479		new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & copy);
 480		new->desc.dsadr = dma_src;
 481		new->desc.dtadr = dma_dst;
 482
 483		if (!first)
 484			first = new;
 485		else
 486			prev->desc.ddadr = new->async_tx.phys;
 487
 488		new->async_tx.cookie = 0;
 489		async_tx_ack(&new->async_tx);
 490
 491		prev = new;
 492		len -= copy;
 493
 494		if (chan->dir == DMA_MEM_TO_DEV) {
 495			dma_src += copy;
 496		} else if (chan->dir == DMA_DEV_TO_MEM) {
 497			dma_dst += copy;
 498		} else if (chan->dir == DMA_MEM_TO_MEM) {
 499			dma_src += copy;
 500			dma_dst += copy;
 501		}
 502
 503		/* Insert the link descriptor to the LD ring */
 504		list_add_tail(&new->node, &first->tx_list);
 505	} while (len);
 506
 507	first->async_tx.flags = flags; /* client is in control of this ack */
 508	first->async_tx.cookie = -EBUSY;
 509
 510	/* last desc and fire IRQ */
 511	new->desc.ddadr = DDADR_STOP;
 512	new->desc.dcmd |= DCMD_ENDIRQEN;
 513
 514	chan->cyclic_first = NULL;
 515
 516	return &first->async_tx;
 517
 518fail:
 519	if (first)
 520		mmp_pdma_free_desc_list(chan, &first->tx_list);
 521	return NULL;
 522}
 523
 524static struct dma_async_tx_descriptor *
 525mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
 526		       unsigned int sg_len, enum dma_transfer_direction dir,
 527		       unsigned long flags, void *context)
 528{
 529	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 530	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new = NULL;
 531	size_t len, avail;
 532	struct scatterlist *sg;
 533	dma_addr_t addr;
 534	int i;
 535
 536	if ((sgl == NULL) || (sg_len == 0))
 537		return NULL;
 538
 539	chan->byte_align = false;
 540
 541	mmp_pdma_config_write(dchan, &chan->slave_config, dir);
 542
 543	for_each_sg(sgl, sg, sg_len, i) {
 544		addr = sg_dma_address(sg);
 545		avail = sg_dma_len(sgl);
 546
 547		do {
 548			len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
 549			if (addr & 0x7)
 550				chan->byte_align = true;
 551
 552			/* allocate and populate the descriptor */
 553			new = mmp_pdma_alloc_descriptor(chan);
 554			if (!new) {
 555				dev_err(chan->dev, "no memory for desc\n");
 556				goto fail;
 557			}
 558
 559			new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & len);
 560			if (dir == DMA_MEM_TO_DEV) {
 561				new->desc.dsadr = addr;
 562				new->desc.dtadr = chan->dev_addr;
 563			} else {
 564				new->desc.dsadr = chan->dev_addr;
 565				new->desc.dtadr = addr;
 566			}
 567
 568			if (!first)
 569				first = new;
 570			else
 571				prev->desc.ddadr = new->async_tx.phys;
 572
 573			new->async_tx.cookie = 0;
 574			async_tx_ack(&new->async_tx);
 575			prev = new;
 576
 577			/* Insert the link descriptor to the LD ring */
 578			list_add_tail(&new->node, &first->tx_list);
 579
 580			/* update metadata */
 581			addr += len;
 582			avail -= len;
 583		} while (avail);
 584	}
 585
 586	first->async_tx.cookie = -EBUSY;
 587	first->async_tx.flags = flags;
 588
 589	/* last desc and fire IRQ */
 590	new->desc.ddadr = DDADR_STOP;
 591	new->desc.dcmd |= DCMD_ENDIRQEN;
 592
 593	chan->dir = dir;
 594	chan->cyclic_first = NULL;
 595
 596	return &first->async_tx;
 597
 598fail:
 599	if (first)
 600		mmp_pdma_free_desc_list(chan, &first->tx_list);
 601	return NULL;
 602}
 603
 604static struct dma_async_tx_descriptor *
 605mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan,
 606			 dma_addr_t buf_addr, size_t len, size_t period_len,
 607			 enum dma_transfer_direction direction,
 608			 unsigned long flags)
 609{
 610	struct mmp_pdma_chan *chan;
 611	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
 612	dma_addr_t dma_src, dma_dst;
 613
 614	if (!dchan || !len || !period_len)
 615		return NULL;
 616
 617	/* the buffer length must be a multiple of period_len */
 618	if (len % period_len != 0)
 619		return NULL;
 620
 621	if (period_len > PDMA_MAX_DESC_BYTES)
 622		return NULL;
 623
 624	chan = to_mmp_pdma_chan(dchan);
 625	mmp_pdma_config_write(dchan, &chan->slave_config, direction);
 626
 627	switch (direction) {
 628	case DMA_MEM_TO_DEV:
 629		dma_src = buf_addr;
 630		dma_dst = chan->dev_addr;
 631		break;
 632	case DMA_DEV_TO_MEM:
 633		dma_dst = buf_addr;
 634		dma_src = chan->dev_addr;
 635		break;
 636	default:
 637		dev_err(chan->dev, "Unsupported direction for cyclic DMA\n");
 638		return NULL;
 639	}
 640
 641	chan->dir = direction;
 642
 643	do {
 644		/* Allocate the link descriptor from DMA pool */
 645		new = mmp_pdma_alloc_descriptor(chan);
 646		if (!new) {
 647			dev_err(chan->dev, "no memory for desc\n");
 648			goto fail;
 649		}
 650
 651		new->desc.dcmd = (chan->dcmd | DCMD_ENDIRQEN |
 652				  (DCMD_LENGTH & period_len));
 653		new->desc.dsadr = dma_src;
 654		new->desc.dtadr = dma_dst;
 655
 656		if (!first)
 657			first = new;
 658		else
 659			prev->desc.ddadr = new->async_tx.phys;
 660
 661		new->async_tx.cookie = 0;
 662		async_tx_ack(&new->async_tx);
 663
 664		prev = new;
 665		len -= period_len;
 666
 667		if (chan->dir == DMA_MEM_TO_DEV)
 668			dma_src += period_len;
 669		else
 670			dma_dst += period_len;
 671
 672		/* Insert the link descriptor to the LD ring */
 673		list_add_tail(&new->node, &first->tx_list);
 674	} while (len);
 675
 676	first->async_tx.flags = flags; /* client is in control of this ack */
 677	first->async_tx.cookie = -EBUSY;
 678
 679	/* make the cyclic link */
 680	new->desc.ddadr = first->async_tx.phys;
 681	chan->cyclic_first = first;
 682
 683	return &first->async_tx;
 684
 685fail:
 686	if (first)
 687		mmp_pdma_free_desc_list(chan, &first->tx_list);
 688	return NULL;
 689}
 690
 691static int mmp_pdma_config_write(struct dma_chan *dchan,
 692			   struct dma_slave_config *cfg,
 693			   enum dma_transfer_direction direction)
 694{
 695	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 696	u32 maxburst = 0, addr = 0;
 697	enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 698
 699	if (!dchan)
 700		return -EINVAL;
 701
 702	if (direction == DMA_DEV_TO_MEM) {
 703		chan->dcmd = DCMD_INCTRGADDR | DCMD_FLOWSRC;
 704		maxburst = cfg->src_maxburst;
 705		width = cfg->src_addr_width;
 706		addr = cfg->src_addr;
 707	} else if (direction == DMA_MEM_TO_DEV) {
 708		chan->dcmd = DCMD_INCSRCADDR | DCMD_FLOWTRG;
 709		maxburst = cfg->dst_maxburst;
 710		width = cfg->dst_addr_width;
 711		addr = cfg->dst_addr;
 712	}
 713
 714	if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
 715		chan->dcmd |= DCMD_WIDTH1;
 716	else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
 717		chan->dcmd |= DCMD_WIDTH2;
 718	else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
 719		chan->dcmd |= DCMD_WIDTH4;
 720
 721	if (maxburst == 8)
 722		chan->dcmd |= DCMD_BURST8;
 723	else if (maxburst == 16)
 724		chan->dcmd |= DCMD_BURST16;
 725	else if (maxburst == 32)
 726		chan->dcmd |= DCMD_BURST32;
 727
 728	chan->dir = direction;
 729	chan->dev_addr = addr;
 730	/* FIXME: drivers should be ported over to use the filter
 731	 * function. Once that's done, the following two lines can
 732	 * be removed.
 733	 */
 734	if (cfg->slave_id)
 735		chan->drcmr = cfg->slave_id;
 736
 737	return 0;
 738}
 739
 740static int mmp_pdma_config(struct dma_chan *dchan,
 741			   struct dma_slave_config *cfg)
 742{
 743	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 744
 745	memcpy(&chan->slave_config, cfg, sizeof(*cfg));
 746	return 0;
 747}
 748
 749static int mmp_pdma_terminate_all(struct dma_chan *dchan)
 750{
 751	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 752	unsigned long flags;
 753
 754	if (!dchan)
 755		return -EINVAL;
 756
 757	disable_chan(chan->phy);
 758	mmp_pdma_free_phy(chan);
 759	spin_lock_irqsave(&chan->desc_lock, flags);
 760	mmp_pdma_free_desc_list(chan, &chan->chain_pending);
 761	mmp_pdma_free_desc_list(chan, &chan->chain_running);
 762	spin_unlock_irqrestore(&chan->desc_lock, flags);
 763	chan->idle = true;
 764
 765	return 0;
 766}
 767
 768static unsigned int mmp_pdma_residue(struct mmp_pdma_chan *chan,
 769				     dma_cookie_t cookie)
 770{
 771	struct mmp_pdma_desc_sw *sw;
 772	u32 curr, residue = 0;
 773	bool passed = false;
 774	bool cyclic = chan->cyclic_first != NULL;
 775
 776	/*
 777	 * If the channel does not have a phy pointer anymore, it has already
 778	 * been completed. Therefore, its residue is 0.
 779	 */
 780	if (!chan->phy)
 781		return 0;
 782
 783	if (chan->dir == DMA_DEV_TO_MEM)
 784		curr = readl(chan->phy->base + DTADR(chan->phy->idx));
 785	else
 786		curr = readl(chan->phy->base + DSADR(chan->phy->idx));
 787
 788	list_for_each_entry(sw, &chan->chain_running, node) {
 789		u32 start, end, len;
 790
 791		if (chan->dir == DMA_DEV_TO_MEM)
 792			start = sw->desc.dtadr;
 793		else
 794			start = sw->desc.dsadr;
 795
 796		len = sw->desc.dcmd & DCMD_LENGTH;
 797		end = start + len;
 798
 799		/*
 800		 * 'passed' will be latched once we found the descriptor which
 801		 * lies inside the boundaries of the curr pointer. All
 802		 * descriptors that occur in the list _after_ we found that
 803		 * partially handled descriptor are still to be processed and
 804		 * are hence added to the residual bytes counter.
 805		 */
 806
 807		if (passed) {
 808			residue += len;
 809		} else if (curr >= start && curr <= end) {
 810			residue += end - curr;
 811			passed = true;
 812		}
 813
 814		/*
 815		 * Descriptors that have the ENDIRQEN bit set mark the end of a
 816		 * transaction chain, and the cookie assigned with it has been
 817		 * returned previously from mmp_pdma_tx_submit().
 818		 *
 819		 * In case we have multiple transactions in the running chain,
 820		 * and the cookie does not match the one the user asked us
 821		 * about, reset the state variables and start over.
 822		 *
 823		 * This logic does not apply to cyclic transactions, where all
 824		 * descriptors have the ENDIRQEN bit set, and for which we
 825		 * can't have multiple transactions on one channel anyway.
 826		 */
 827		if (cyclic || !(sw->desc.dcmd & DCMD_ENDIRQEN))
 828			continue;
 829
 830		if (sw->async_tx.cookie == cookie) {
 831			return residue;
 832		} else {
 833			residue = 0;
 834			passed = false;
 835		}
 836	}
 837
 838	/* We should only get here in case of cyclic transactions */
 839	return residue;
 840}
 841
 842static enum dma_status mmp_pdma_tx_status(struct dma_chan *dchan,
 843					  dma_cookie_t cookie,
 844					  struct dma_tx_state *txstate)
 845{
 846	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 847	enum dma_status ret;
 848
 849	ret = dma_cookie_status(dchan, cookie, txstate);
 850	if (likely(ret != DMA_ERROR))
 851		dma_set_residue(txstate, mmp_pdma_residue(chan, cookie));
 852
 853	return ret;
 854}
 855
 856/*
 857 * mmp_pdma_issue_pending - Issue the DMA start command
 858 * pending list ==> running list
 859 */
 860static void mmp_pdma_issue_pending(struct dma_chan *dchan)
 861{
 862	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 863	unsigned long flags;
 864
 865	spin_lock_irqsave(&chan->desc_lock, flags);
 866	start_pending_queue(chan);
 867	spin_unlock_irqrestore(&chan->desc_lock, flags);
 868}
 869
 870/*
 871 * dma_do_tasklet
 872 * Do call back
 873 * Start pending list
 874 */
 875static void dma_do_tasklet(struct tasklet_struct *t)
 876{
 877	struct mmp_pdma_chan *chan = from_tasklet(chan, t, tasklet);
 878	struct mmp_pdma_desc_sw *desc, *_desc;
 879	LIST_HEAD(chain_cleanup);
 880	unsigned long flags;
 881	struct dmaengine_desc_callback cb;
 882
 883	if (chan->cyclic_first) {
 884		spin_lock_irqsave(&chan->desc_lock, flags);
 885		desc = chan->cyclic_first;
 886		dmaengine_desc_get_callback(&desc->async_tx, &cb);
 887		spin_unlock_irqrestore(&chan->desc_lock, flags);
 888
 889		dmaengine_desc_callback_invoke(&cb, NULL);
 890
 891		return;
 892	}
 893
 894	/* submit pending list; callback for each desc; free desc */
 895	spin_lock_irqsave(&chan->desc_lock, flags);
 896
 897	list_for_each_entry_safe(desc, _desc, &chan->chain_running, node) {
 898		/*
 899		 * move the descriptors to a temporary list so we can drop
 900		 * the lock during the entire cleanup operation
 901		 */
 902		list_move(&desc->node, &chain_cleanup);
 903
 904		/*
 905		 * Look for the first list entry which has the ENDIRQEN flag
 906		 * set. That is the descriptor we got an interrupt for, so
 907		 * complete that transaction and its cookie.
 908		 */
 909		if (desc->desc.dcmd & DCMD_ENDIRQEN) {
 910			dma_cookie_t cookie = desc->async_tx.cookie;
 911			dma_cookie_complete(&desc->async_tx);
 912			dev_dbg(chan->dev, "completed_cookie=%d\n", cookie);
 913			break;
 914		}
 915	}
 916
 917	/*
 918	 * The hardware is idle and ready for more when the
 919	 * chain_running list is empty.
 920	 */
 921	chan->idle = list_empty(&chan->chain_running);
 922
 923	/* Start any pending transactions automatically */
 924	start_pending_queue(chan);
 925	spin_unlock_irqrestore(&chan->desc_lock, flags);
 926
 927	/* Run the callback for each descriptor, in order */
 928	list_for_each_entry_safe(desc, _desc, &chain_cleanup, node) {
 929		struct dma_async_tx_descriptor *txd = &desc->async_tx;
 930
 931		/* Remove from the list of transactions */
 932		list_del(&desc->node);
 933		/* Run the link descriptor callback function */
 934		dmaengine_desc_get_callback(txd, &cb);
 935		dmaengine_desc_callback_invoke(&cb, NULL);
 936
 937		dma_pool_free(chan->desc_pool, desc, txd->phys);
 938	}
 939}
 940
 941static int mmp_pdma_remove(struct platform_device *op)
 942{
 943	struct mmp_pdma_device *pdev = platform_get_drvdata(op);
 944	struct mmp_pdma_phy *phy;
 945	int i, irq = 0, irq_num = 0;
 946
 947	if (op->dev.of_node)
 948		of_dma_controller_free(op->dev.of_node);
 949
 950	for (i = 0; i < pdev->dma_channels; i++) {
 951		if (platform_get_irq(op, i) > 0)
 952			irq_num++;
 953	}
 954
 955	if (irq_num != pdev->dma_channels) {
 956		irq = platform_get_irq(op, 0);
 957		devm_free_irq(&op->dev, irq, pdev);
 958	} else {
 959		for (i = 0; i < pdev->dma_channels; i++) {
 960			phy = &pdev->phy[i];
 961			irq = platform_get_irq(op, i);
 962			devm_free_irq(&op->dev, irq, phy);
 963		}
 964	}
 965
 966	dma_async_device_unregister(&pdev->device);
 967	return 0;
 968}
 969
 970static int mmp_pdma_chan_init(struct mmp_pdma_device *pdev, int idx, int irq)
 971{
 972	struct mmp_pdma_phy *phy  = &pdev->phy[idx];
 973	struct mmp_pdma_chan *chan;
 974	int ret;
 975
 976	chan = devm_kzalloc(pdev->dev, sizeof(*chan), GFP_KERNEL);
 977	if (chan == NULL)
 978		return -ENOMEM;
 979
 980	phy->idx = idx;
 981	phy->base = pdev->base;
 982
 983	if (irq) {
 984		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_chan_handler,
 985				       IRQF_SHARED, "pdma", phy);
 986		if (ret) {
 987			dev_err(pdev->dev, "channel request irq fail!\n");
 988			return ret;
 989		}
 990	}
 991
 992	spin_lock_init(&chan->desc_lock);
 993	chan->dev = pdev->dev;
 994	chan->chan.device = &pdev->device;
 995	tasklet_setup(&chan->tasklet, dma_do_tasklet);
 996	INIT_LIST_HEAD(&chan->chain_pending);
 997	INIT_LIST_HEAD(&chan->chain_running);
 998
 999	/* register virt channel to dma engine */
1000	list_add_tail(&chan->chan.device_node, &pdev->device.channels);
1001
1002	return 0;
1003}
1004
1005static const struct of_device_id mmp_pdma_dt_ids[] = {
1006	{ .compatible = "marvell,pdma-1.0", },
1007	{}
1008};
1009MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids);
1010
1011static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec,
1012					   struct of_dma *ofdma)
1013{
1014	struct mmp_pdma_device *d = ofdma->of_dma_data;
1015	struct dma_chan *chan;
1016
1017	chan = dma_get_any_slave_channel(&d->device);
1018	if (!chan)
1019		return NULL;
1020
1021	to_mmp_pdma_chan(chan)->drcmr = dma_spec->args[0];
1022
1023	return chan;
1024}
1025
1026static int mmp_pdma_probe(struct platform_device *op)
1027{
1028	struct mmp_pdma_device *pdev;
1029	const struct of_device_id *of_id;
1030	struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1031	struct resource *iores;
1032	int i, ret, irq = 0;
1033	int dma_channels = 0, irq_num = 0;
1034	const enum dma_slave_buswidth widths =
1035		DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1036		DMA_SLAVE_BUSWIDTH_4_BYTES;
1037
1038	pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1039	if (!pdev)
1040		return -ENOMEM;
1041
1042	pdev->dev = &op->dev;
1043
1044	spin_lock_init(&pdev->phy_lock);
1045
1046	iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1047	pdev->base = devm_ioremap_resource(pdev->dev, iores);
1048	if (IS_ERR(pdev->base))
1049		return PTR_ERR(pdev->base);
1050
1051	of_id = of_match_device(mmp_pdma_dt_ids, pdev->dev);
1052	if (of_id)
1053		of_property_read_u32(pdev->dev->of_node, "#dma-channels",
1054				     &dma_channels);
1055	else if (pdata && pdata->dma_channels)
1056		dma_channels = pdata->dma_channels;
1057	else
1058		dma_channels = 32;	/* default 32 channel */
1059	pdev->dma_channels = dma_channels;
1060
1061	for (i = 0; i < dma_channels; i++) {
1062		if (platform_get_irq_optional(op, i) > 0)
1063			irq_num++;
1064	}
1065
1066	pdev->phy = devm_kcalloc(pdev->dev, dma_channels, sizeof(*pdev->phy),
1067				 GFP_KERNEL);
1068	if (pdev->phy == NULL)
1069		return -ENOMEM;
1070
1071	INIT_LIST_HEAD(&pdev->device.channels);
1072
1073	if (irq_num != dma_channels) {
1074		/* all chan share one irq, demux inside */
1075		irq = platform_get_irq(op, 0);
1076		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_int_handler,
1077				       IRQF_SHARED, "pdma", pdev);
1078		if (ret)
1079			return ret;
1080	}
1081
1082	for (i = 0; i < dma_channels; i++) {
1083		irq = (irq_num != dma_channels) ? 0 : platform_get_irq(op, i);
1084		ret = mmp_pdma_chan_init(pdev, i, irq);
1085		if (ret)
1086			return ret;
1087	}
1088
1089	dma_cap_set(DMA_SLAVE, pdev->device.cap_mask);
1090	dma_cap_set(DMA_MEMCPY, pdev->device.cap_mask);
1091	dma_cap_set(DMA_CYCLIC, pdev->device.cap_mask);
1092	dma_cap_set(DMA_PRIVATE, pdev->device.cap_mask);
1093	pdev->device.dev = &op->dev;
1094	pdev->device.device_alloc_chan_resources = mmp_pdma_alloc_chan_resources;
1095	pdev->device.device_free_chan_resources = mmp_pdma_free_chan_resources;
1096	pdev->device.device_tx_status = mmp_pdma_tx_status;
1097	pdev->device.device_prep_dma_memcpy = mmp_pdma_prep_memcpy;
1098	pdev->device.device_prep_slave_sg = mmp_pdma_prep_slave_sg;
1099	pdev->device.device_prep_dma_cyclic = mmp_pdma_prep_dma_cyclic;
1100	pdev->device.device_issue_pending = mmp_pdma_issue_pending;
1101	pdev->device.device_config = mmp_pdma_config;
1102	pdev->device.device_terminate_all = mmp_pdma_terminate_all;
1103	pdev->device.copy_align = DMAENGINE_ALIGN_8_BYTES;
1104	pdev->device.src_addr_widths = widths;
1105	pdev->device.dst_addr_widths = widths;
1106	pdev->device.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1107	pdev->device.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1108
1109	if (pdev->dev->coherent_dma_mask)
1110		dma_set_mask(pdev->dev, pdev->dev->coherent_dma_mask);
1111	else
1112		dma_set_mask(pdev->dev, DMA_BIT_MASK(64));
1113
1114	ret = dma_async_device_register(&pdev->device);
1115	if (ret) {
1116		dev_err(pdev->device.dev, "unable to register\n");
1117		return ret;
1118	}
1119
1120	if (op->dev.of_node) {
1121		/* Device-tree DMA controller registration */
1122		ret = of_dma_controller_register(op->dev.of_node,
1123						 mmp_pdma_dma_xlate, pdev);
1124		if (ret < 0) {
1125			dev_err(&op->dev, "of_dma_controller_register failed\n");
1126			return ret;
1127		}
1128	}
1129
1130	platform_set_drvdata(op, pdev);
1131	dev_info(pdev->device.dev, "initialized %d channels\n", dma_channels);
1132	return 0;
1133}
1134
1135static const struct platform_device_id mmp_pdma_id_table[] = {
1136	{ "mmp-pdma", },
1137	{ },
1138};
1139
1140static struct platform_driver mmp_pdma_driver = {
1141	.driver		= {
1142		.name	= "mmp-pdma",
1143		.of_match_table = mmp_pdma_dt_ids,
1144	},
1145	.id_table	= mmp_pdma_id_table,
1146	.probe		= mmp_pdma_probe,
1147	.remove		= mmp_pdma_remove,
1148};
 
 
 
 
 
 
 
 
 
 
 
 
 
1149
1150module_platform_driver(mmp_pdma_driver);
1151
1152MODULE_DESCRIPTION("MARVELL MMP Peripheral DMA Driver");
1153MODULE_AUTHOR("Marvell International Ltd.");
1154MODULE_LICENSE("GPL v2");