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v6.8
   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_dma.h>
  19#include <linux/of.h>
 
  20
  21#include "dmaengine.h"
  22
  23#define DCSR		0x0000
  24#define DALGN		0x00a0
  25#define DINT		0x00f0
  26#define DDADR		0x0200
  27#define DSADR(n)	(0x0204 + ((n) << 4))
  28#define DTADR(n)	(0x0208 + ((n) << 4))
  29#define DCMD		0x020c
  30
  31#define DCSR_RUN	BIT(31)	/* Run Bit (read / write) */
  32#define DCSR_NODESC	BIT(30)	/* No-Descriptor Fetch (read / write) */
  33#define DCSR_STOPIRQEN	BIT(29)	/* Stop Interrupt Enable (read / write) */
  34#define DCSR_REQPEND	BIT(8)	/* Request Pending (read-only) */
  35#define DCSR_STOPSTATE	BIT(3)	/* Stop State (read-only) */
  36#define DCSR_ENDINTR	BIT(2)	/* End Interrupt (read / write) */
  37#define DCSR_STARTINTR	BIT(1)	/* Start Interrupt (read / write) */
  38#define DCSR_BUSERR	BIT(0)	/* Bus Error Interrupt (read / write) */
  39
  40#define DCSR_EORIRQEN	BIT(28)	/* End of Receive Interrupt Enable (R/W) */
  41#define DCSR_EORJMPEN	BIT(27)	/* Jump to next descriptor on EOR */
  42#define DCSR_EORSTOPEN	BIT(26)	/* STOP on an EOR */
  43#define DCSR_SETCMPST	BIT(25)	/* Set Descriptor Compare Status */
  44#define DCSR_CLRCMPST	BIT(24)	/* Clear Descriptor Compare Status */
  45#define DCSR_CMPST	BIT(10)	/* The Descriptor Compare Status */
  46#define DCSR_EORINTR	BIT(9)	/* The end of Receive */
  47
  48#define DRCMR(n)	((((n) < 64) ? 0x0100 : 0x1100) + (((n) & 0x3f) << 2))
  49#define DRCMR_MAPVLD	BIT(7)	/* Map Valid (read / write) */
  50#define DRCMR_CHLNUM	0x1f	/* mask for Channel Number (read / write) */
  51
  52#define DDADR_DESCADDR	0xfffffff0	/* Address of next descriptor (mask) */
  53#define DDADR_STOP	BIT(0)	/* Stop (read / write) */
  54
  55#define DCMD_INCSRCADDR	BIT(31)	/* Source Address Increment Setting. */
  56#define DCMD_INCTRGADDR	BIT(30)	/* Target Address Increment Setting. */
  57#define DCMD_FLOWSRC	BIT(29)	/* Flow Control by the source. */
  58#define DCMD_FLOWTRG	BIT(28)	/* Flow Control by the target. */
  59#define DCMD_STARTIRQEN	BIT(22)	/* Start Interrupt Enable */
  60#define DCMD_ENDIRQEN	BIT(21)	/* End Interrupt Enable */
  61#define DCMD_ENDIAN	BIT(18)	/* Device Endian-ness. */
  62#define DCMD_BURST8	(1 << 16)	/* 8 byte burst */
  63#define DCMD_BURST16	(2 << 16)	/* 16 byte burst */
  64#define DCMD_BURST32	(3 << 16)	/* 32 byte burst */
  65#define DCMD_WIDTH1	(1 << 14)	/* 1 byte width */
  66#define DCMD_WIDTH2	(2 << 14)	/* 2 byte width (HalfWord) */
  67#define DCMD_WIDTH4	(3 << 14)	/* 4 byte width (Word) */
  68#define DCMD_LENGTH	0x01fff		/* length mask (max = 8K - 1) */
  69
  70#define PDMA_MAX_DESC_BYTES	DCMD_LENGTH
  71
  72struct mmp_pdma_desc_hw {
  73	u32 ddadr;	/* Points to the next descriptor + flags */
  74	u32 dsadr;	/* DSADR value for the current transfer */
  75	u32 dtadr;	/* DTADR value for the current transfer */
  76	u32 dcmd;	/* DCMD value for the current transfer */
  77} __aligned(32);
  78
  79struct mmp_pdma_desc_sw {
  80	struct mmp_pdma_desc_hw desc;
  81	struct list_head node;
  82	struct list_head tx_list;
  83	struct dma_async_tx_descriptor async_tx;
  84};
  85
  86struct mmp_pdma_phy;
  87
  88struct mmp_pdma_chan {
  89	struct device *dev;
  90	struct dma_chan chan;
  91	struct dma_async_tx_descriptor desc;
  92	struct mmp_pdma_phy *phy;
  93	enum dma_transfer_direction dir;
  94	struct dma_slave_config slave_config;
  95
  96	struct mmp_pdma_desc_sw *cyclic_first;	/* first desc_sw if channel
  97						 * is in cyclic mode */
  98
  99	/* channel's basic info */
 100	struct tasklet_struct tasklet;
 101	u32 dcmd;
 102	u32 drcmr;
 103	u32 dev_addr;
 104
 105	/* list for desc */
 106	spinlock_t desc_lock;		/* Descriptor list lock */
 107	struct list_head chain_pending;	/* Link descriptors queue for pending */
 108	struct list_head chain_running;	/* Link descriptors queue for running */
 109	bool idle;			/* channel statue machine */
 110	bool byte_align;
 111
 112	struct dma_pool *desc_pool;	/* Descriptors pool */
 113};
 114
 115struct mmp_pdma_phy {
 116	int idx;
 117	void __iomem *base;
 118	struct mmp_pdma_chan *vchan;
 119};
 120
 121struct mmp_pdma_device {
 122	int				dma_channels;
 123	void __iomem			*base;
 124	struct device			*dev;
 125	struct dma_device		device;
 126	struct mmp_pdma_phy		*phy;
 127	spinlock_t phy_lock; /* protect alloc/free phy channels */
 128};
 129
 130#define tx_to_mmp_pdma_desc(tx)					\
 131	container_of(tx, struct mmp_pdma_desc_sw, async_tx)
 132#define to_mmp_pdma_desc(lh)					\
 133	container_of(lh, struct mmp_pdma_desc_sw, node)
 134#define to_mmp_pdma_chan(dchan)					\
 135	container_of(dchan, struct mmp_pdma_chan, chan)
 136#define to_mmp_pdma_dev(dmadev)					\
 137	container_of(dmadev, struct mmp_pdma_device, device)
 138
 139static int mmp_pdma_config_write(struct dma_chan *dchan,
 140			   struct dma_slave_config *cfg,
 141			   enum dma_transfer_direction direction);
 142
 143static void set_desc(struct mmp_pdma_phy *phy, dma_addr_t addr)
 144{
 145	u32 reg = (phy->idx << 4) + DDADR;
 146
 147	writel(addr, phy->base + reg);
 148}
 149
 150static void enable_chan(struct mmp_pdma_phy *phy)
 151{
 152	u32 reg, dalgn;
 153
 154	if (!phy->vchan)
 155		return;
 156
 157	reg = DRCMR(phy->vchan->drcmr);
 158	writel(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 159
 160	dalgn = readl(phy->base + DALGN);
 161	if (phy->vchan->byte_align)
 162		dalgn |= 1 << phy->idx;
 163	else
 164		dalgn &= ~(1 << phy->idx);
 165	writel(dalgn, phy->base + DALGN);
 166
 167	reg = (phy->idx << 2) + DCSR;
 168	writel(readl(phy->base + reg) | DCSR_RUN, phy->base + reg);
 169}
 170
 171static void disable_chan(struct mmp_pdma_phy *phy)
 172{
 173	u32 reg;
 174
 175	if (!phy)
 176		return;
 177
 178	reg = (phy->idx << 2) + DCSR;
 179	writel(readl(phy->base + reg) & ~DCSR_RUN, phy->base + reg);
 180}
 181
 182static int clear_chan_irq(struct mmp_pdma_phy *phy)
 183{
 184	u32 dcsr;
 185	u32 dint = readl(phy->base + DINT);
 186	u32 reg = (phy->idx << 2) + DCSR;
 187
 188	if (!(dint & BIT(phy->idx)))
 189		return -EAGAIN;
 190
 191	/* clear irq */
 192	dcsr = readl(phy->base + reg);
 193	writel(dcsr, phy->base + reg);
 194	if ((dcsr & DCSR_BUSERR) && (phy->vchan))
 195		dev_warn(phy->vchan->dev, "DCSR_BUSERR\n");
 196
 197	return 0;
 198}
 199
 200static irqreturn_t mmp_pdma_chan_handler(int irq, void *dev_id)
 201{
 202	struct mmp_pdma_phy *phy = dev_id;
 203
 204	if (clear_chan_irq(phy) != 0)
 205		return IRQ_NONE;
 206
 207	tasklet_schedule(&phy->vchan->tasklet);
 208	return IRQ_HANDLED;
 209}
 210
 211static irqreturn_t mmp_pdma_int_handler(int irq, void *dev_id)
 212{
 213	struct mmp_pdma_device *pdev = dev_id;
 214	struct mmp_pdma_phy *phy;
 215	u32 dint = readl(pdev->base + DINT);
 216	int i, ret;
 217	int irq_num = 0;
 218
 219	while (dint) {
 220		i = __ffs(dint);
 221		/* only handle interrupts belonging to pdma driver*/
 222		if (i >= pdev->dma_channels)
 223			break;
 224		dint &= (dint - 1);
 225		phy = &pdev->phy[i];
 226		ret = mmp_pdma_chan_handler(irq, phy);
 227		if (ret == IRQ_HANDLED)
 228			irq_num++;
 229	}
 230
 231	if (irq_num)
 232		return IRQ_HANDLED;
 233
 234	return IRQ_NONE;
 235}
 236
 237/* lookup free phy channel as descending priority */
 238static struct mmp_pdma_phy *lookup_phy(struct mmp_pdma_chan *pchan)
 239{
 240	int prio, i;
 241	struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
 242	struct mmp_pdma_phy *phy, *found = NULL;
 243	unsigned long flags;
 244
 245	/*
 246	 * dma channel priorities
 247	 * ch 0 - 3,  16 - 19  <--> (0)
 248	 * ch 4 - 7,  20 - 23  <--> (1)
 249	 * ch 8 - 11, 24 - 27  <--> (2)
 250	 * ch 12 - 15, 28 - 31  <--> (3)
 251	 */
 252
 253	spin_lock_irqsave(&pdev->phy_lock, flags);
 254	for (prio = 0; prio <= ((pdev->dma_channels - 1) & 0xf) >> 2; prio++) {
 255		for (i = 0; i < pdev->dma_channels; i++) {
 256			if (prio != (i & 0xf) >> 2)
 257				continue;
 258			phy = &pdev->phy[i];
 259			if (!phy->vchan) {
 260				phy->vchan = pchan;
 261				found = phy;
 262				goto out_unlock;
 263			}
 264		}
 265	}
 266
 267out_unlock:
 268	spin_unlock_irqrestore(&pdev->phy_lock, flags);
 269	return found;
 270}
 271
 272static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan)
 273{
 274	struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
 275	unsigned long flags;
 276	u32 reg;
 277
 278	if (!pchan->phy)
 279		return;
 280
 281	/* clear the channel mapping in DRCMR */
 282	reg = DRCMR(pchan->drcmr);
 283	writel(0, pchan->phy->base + reg);
 284
 285	spin_lock_irqsave(&pdev->phy_lock, flags);
 286	pchan->phy->vchan = NULL;
 287	pchan->phy = NULL;
 288	spin_unlock_irqrestore(&pdev->phy_lock, flags);
 289}
 290
 291/*
 292 * start_pending_queue - transfer any pending transactions
 293 * pending list ==> running list
 294 */
 295static void start_pending_queue(struct mmp_pdma_chan *chan)
 296{
 297	struct mmp_pdma_desc_sw *desc;
 298
 299	/* still in running, irq will start the pending list */
 300	if (!chan->idle) {
 301		dev_dbg(chan->dev, "DMA controller still busy\n");
 302		return;
 303	}
 304
 305	if (list_empty(&chan->chain_pending)) {
 306		/* chance to re-fetch phy channel with higher prio */
 307		mmp_pdma_free_phy(chan);
 308		dev_dbg(chan->dev, "no pending list\n");
 309		return;
 310	}
 311
 312	if (!chan->phy) {
 313		chan->phy = lookup_phy(chan);
 314		if (!chan->phy) {
 315			dev_dbg(chan->dev, "no free dma channel\n");
 316			return;
 317		}
 318	}
 319
 320	/*
 321	 * pending -> running
 322	 * reintilize pending list
 323	 */
 324	desc = list_first_entry(&chan->chain_pending,
 325				struct mmp_pdma_desc_sw, node);
 326	list_splice_tail_init(&chan->chain_pending, &chan->chain_running);
 327
 328	/*
 329	 * Program the descriptor's address into the DMA controller,
 330	 * then start the DMA transaction
 331	 */
 332	set_desc(chan->phy, desc->async_tx.phys);
 333	enable_chan(chan->phy);
 334	chan->idle = false;
 335}
 336
 337
 338/* desc->tx_list ==> pending list */
 339static dma_cookie_t mmp_pdma_tx_submit(struct dma_async_tx_descriptor *tx)
 340{
 341	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(tx->chan);
 342	struct mmp_pdma_desc_sw *desc = tx_to_mmp_pdma_desc(tx);
 343	struct mmp_pdma_desc_sw *child;
 344	unsigned long flags;
 345	dma_cookie_t cookie = -EBUSY;
 346
 347	spin_lock_irqsave(&chan->desc_lock, flags);
 348
 349	list_for_each_entry(child, &desc->tx_list, node) {
 350		cookie = dma_cookie_assign(&child->async_tx);
 351	}
 352
 353	/* softly link to pending list - desc->tx_list ==> pending list */
 354	list_splice_tail_init(&desc->tx_list, &chan->chain_pending);
 355
 356	spin_unlock_irqrestore(&chan->desc_lock, flags);
 357
 358	return cookie;
 359}
 360
 361static struct mmp_pdma_desc_sw *
 362mmp_pdma_alloc_descriptor(struct mmp_pdma_chan *chan)
 363{
 364	struct mmp_pdma_desc_sw *desc;
 365	dma_addr_t pdesc;
 366
 367	desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &pdesc);
 368	if (!desc) {
 369		dev_err(chan->dev, "out of memory for link descriptor\n");
 370		return NULL;
 371	}
 372
 373	INIT_LIST_HEAD(&desc->tx_list);
 374	dma_async_tx_descriptor_init(&desc->async_tx, &chan->chan);
 375	/* each desc has submit */
 376	desc->async_tx.tx_submit = mmp_pdma_tx_submit;
 377	desc->async_tx.phys = pdesc;
 378
 379	return desc;
 380}
 381
 382/*
 383 * mmp_pdma_alloc_chan_resources - Allocate resources for DMA channel.
 384 *
 385 * This function will create a dma pool for descriptor allocation.
 386 * Request irq only when channel is requested
 387 * Return - The number of allocated descriptors.
 388 */
 389
 390static int mmp_pdma_alloc_chan_resources(struct dma_chan *dchan)
 391{
 392	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 393
 394	if (chan->desc_pool)
 395		return 1;
 396
 397	chan->desc_pool = dma_pool_create(dev_name(&dchan->dev->device),
 398					  chan->dev,
 399					  sizeof(struct mmp_pdma_desc_sw),
 400					  __alignof__(struct mmp_pdma_desc_sw),
 401					  0);
 402	if (!chan->desc_pool) {
 403		dev_err(chan->dev, "unable to allocate descriptor pool\n");
 404		return -ENOMEM;
 405	}
 406
 407	mmp_pdma_free_phy(chan);
 408	chan->idle = true;
 409	chan->dev_addr = 0;
 410	return 1;
 411}
 412
 413static void mmp_pdma_free_desc_list(struct mmp_pdma_chan *chan,
 414				    struct list_head *list)
 415{
 416	struct mmp_pdma_desc_sw *desc, *_desc;
 417
 418	list_for_each_entry_safe(desc, _desc, list, node) {
 419		list_del(&desc->node);
 420		dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
 421	}
 422}
 423
 424static void mmp_pdma_free_chan_resources(struct dma_chan *dchan)
 425{
 426	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 427	unsigned long flags;
 428
 429	spin_lock_irqsave(&chan->desc_lock, flags);
 430	mmp_pdma_free_desc_list(chan, &chan->chain_pending);
 431	mmp_pdma_free_desc_list(chan, &chan->chain_running);
 432	spin_unlock_irqrestore(&chan->desc_lock, flags);
 433
 434	dma_pool_destroy(chan->desc_pool);
 435	chan->desc_pool = NULL;
 436	chan->idle = true;
 437	chan->dev_addr = 0;
 438	mmp_pdma_free_phy(chan);
 439	return;
 440}
 441
 442static struct dma_async_tx_descriptor *
 443mmp_pdma_prep_memcpy(struct dma_chan *dchan,
 444		     dma_addr_t dma_dst, dma_addr_t dma_src,
 445		     size_t len, unsigned long flags)
 446{
 447	struct mmp_pdma_chan *chan;
 448	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
 449	size_t copy = 0;
 450
 451	if (!dchan)
 452		return NULL;
 453
 454	if (!len)
 455		return NULL;
 456
 457	chan = to_mmp_pdma_chan(dchan);
 458	chan->byte_align = false;
 459
 460	if (!chan->dir) {
 461		chan->dir = DMA_MEM_TO_MEM;
 462		chan->dcmd = DCMD_INCTRGADDR | DCMD_INCSRCADDR;
 463		chan->dcmd |= DCMD_BURST32;
 464	}
 465
 466	do {
 467		/* Allocate the link descriptor from DMA pool */
 468		new = mmp_pdma_alloc_descriptor(chan);
 469		if (!new) {
 470			dev_err(chan->dev, "no memory for desc\n");
 471			goto fail;
 472		}
 473
 474		copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
 475		if (dma_src & 0x7 || dma_dst & 0x7)
 476			chan->byte_align = true;
 477
 478		new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & copy);
 479		new->desc.dsadr = dma_src;
 480		new->desc.dtadr = dma_dst;
 481
 482		if (!first)
 483			first = new;
 484		else
 485			prev->desc.ddadr = new->async_tx.phys;
 486
 487		new->async_tx.cookie = 0;
 488		async_tx_ack(&new->async_tx);
 489
 490		prev = new;
 491		len -= copy;
 492
 493		if (chan->dir == DMA_MEM_TO_DEV) {
 494			dma_src += copy;
 495		} else if (chan->dir == DMA_DEV_TO_MEM) {
 496			dma_dst += copy;
 497		} else if (chan->dir == DMA_MEM_TO_MEM) {
 498			dma_src += copy;
 499			dma_dst += copy;
 500		}
 501
 502		/* Insert the link descriptor to the LD ring */
 503		list_add_tail(&new->node, &first->tx_list);
 504	} while (len);
 505
 506	first->async_tx.flags = flags; /* client is in control of this ack */
 507	first->async_tx.cookie = -EBUSY;
 508
 509	/* last desc and fire IRQ */
 510	new->desc.ddadr = DDADR_STOP;
 511	new->desc.dcmd |= DCMD_ENDIRQEN;
 512
 513	chan->cyclic_first = NULL;
 514
 515	return &first->async_tx;
 516
 517fail:
 518	if (first)
 519		mmp_pdma_free_desc_list(chan, &first->tx_list);
 520	return NULL;
 521}
 522
 523static struct dma_async_tx_descriptor *
 524mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
 525		       unsigned int sg_len, enum dma_transfer_direction dir,
 526		       unsigned long flags, void *context)
 527{
 528	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 529	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new = NULL;
 530	size_t len, avail;
 531	struct scatterlist *sg;
 532	dma_addr_t addr;
 533	int i;
 534
 535	if ((sgl == NULL) || (sg_len == 0))
 536		return NULL;
 537
 538	chan->byte_align = false;
 539
 540	mmp_pdma_config_write(dchan, &chan->slave_config, dir);
 541
 542	for_each_sg(sgl, sg, sg_len, i) {
 543		addr = sg_dma_address(sg);
 544		avail = sg_dma_len(sgl);
 545
 546		do {
 547			len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
 548			if (addr & 0x7)
 549				chan->byte_align = true;
 550
 551			/* allocate and populate the descriptor */
 552			new = mmp_pdma_alloc_descriptor(chan);
 553			if (!new) {
 554				dev_err(chan->dev, "no memory for desc\n");
 555				goto fail;
 556			}
 557
 558			new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & len);
 559			if (dir == DMA_MEM_TO_DEV) {
 560				new->desc.dsadr = addr;
 561				new->desc.dtadr = chan->dev_addr;
 562			} else {
 563				new->desc.dsadr = chan->dev_addr;
 564				new->desc.dtadr = addr;
 565			}
 566
 567			if (!first)
 568				first = new;
 569			else
 570				prev->desc.ddadr = new->async_tx.phys;
 571
 572			new->async_tx.cookie = 0;
 573			async_tx_ack(&new->async_tx);
 574			prev = new;
 575
 576			/* Insert the link descriptor to the LD ring */
 577			list_add_tail(&new->node, &first->tx_list);
 578
 579			/* update metadata */
 580			addr += len;
 581			avail -= len;
 582		} while (avail);
 583	}
 584
 585	first->async_tx.cookie = -EBUSY;
 586	first->async_tx.flags = flags;
 587
 588	/* last desc and fire IRQ */
 589	new->desc.ddadr = DDADR_STOP;
 590	new->desc.dcmd |= DCMD_ENDIRQEN;
 591
 592	chan->dir = dir;
 593	chan->cyclic_first = NULL;
 594
 595	return &first->async_tx;
 596
 597fail:
 598	if (first)
 599		mmp_pdma_free_desc_list(chan, &first->tx_list);
 600	return NULL;
 601}
 602
 603static struct dma_async_tx_descriptor *
 604mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan,
 605			 dma_addr_t buf_addr, size_t len, size_t period_len,
 606			 enum dma_transfer_direction direction,
 607			 unsigned long flags)
 608{
 609	struct mmp_pdma_chan *chan;
 610	struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
 611	dma_addr_t dma_src, dma_dst;
 612
 613	if (!dchan || !len || !period_len)
 614		return NULL;
 615
 616	/* the buffer length must be a multiple of period_len */
 617	if (len % period_len != 0)
 618		return NULL;
 619
 620	if (period_len > PDMA_MAX_DESC_BYTES)
 621		return NULL;
 622
 623	chan = to_mmp_pdma_chan(dchan);
 624	mmp_pdma_config_write(dchan, &chan->slave_config, direction);
 625
 626	switch (direction) {
 627	case DMA_MEM_TO_DEV:
 628		dma_src = buf_addr;
 629		dma_dst = chan->dev_addr;
 630		break;
 631	case DMA_DEV_TO_MEM:
 632		dma_dst = buf_addr;
 633		dma_src = chan->dev_addr;
 634		break;
 635	default:
 636		dev_err(chan->dev, "Unsupported direction for cyclic DMA\n");
 637		return NULL;
 638	}
 639
 640	chan->dir = direction;
 641
 642	do {
 643		/* Allocate the link descriptor from DMA pool */
 644		new = mmp_pdma_alloc_descriptor(chan);
 645		if (!new) {
 646			dev_err(chan->dev, "no memory for desc\n");
 647			goto fail;
 648		}
 649
 650		new->desc.dcmd = (chan->dcmd | DCMD_ENDIRQEN |
 651				  (DCMD_LENGTH & period_len));
 652		new->desc.dsadr = dma_src;
 653		new->desc.dtadr = dma_dst;
 654
 655		if (!first)
 656			first = new;
 657		else
 658			prev->desc.ddadr = new->async_tx.phys;
 659
 660		new->async_tx.cookie = 0;
 661		async_tx_ack(&new->async_tx);
 662
 663		prev = new;
 664		len -= period_len;
 665
 666		if (chan->dir == DMA_MEM_TO_DEV)
 667			dma_src += period_len;
 668		else
 669			dma_dst += period_len;
 670
 671		/* Insert the link descriptor to the LD ring */
 672		list_add_tail(&new->node, &first->tx_list);
 673	} while (len);
 674
 675	first->async_tx.flags = flags; /* client is in control of this ack */
 676	first->async_tx.cookie = -EBUSY;
 677
 678	/* make the cyclic link */
 679	new->desc.ddadr = first->async_tx.phys;
 680	chan->cyclic_first = first;
 681
 682	return &first->async_tx;
 683
 684fail:
 685	if (first)
 686		mmp_pdma_free_desc_list(chan, &first->tx_list);
 687	return NULL;
 688}
 689
 690static int mmp_pdma_config_write(struct dma_chan *dchan,
 691			   struct dma_slave_config *cfg,
 692			   enum dma_transfer_direction direction)
 693{
 694	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 695	u32 maxburst = 0, addr = 0;
 696	enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 697
 698	if (!dchan)
 699		return -EINVAL;
 700
 701	if (direction == DMA_DEV_TO_MEM) {
 702		chan->dcmd = DCMD_INCTRGADDR | DCMD_FLOWSRC;
 703		maxburst = cfg->src_maxburst;
 704		width = cfg->src_addr_width;
 705		addr = cfg->src_addr;
 706	} else if (direction == DMA_MEM_TO_DEV) {
 707		chan->dcmd = DCMD_INCSRCADDR | DCMD_FLOWTRG;
 708		maxburst = cfg->dst_maxburst;
 709		width = cfg->dst_addr_width;
 710		addr = cfg->dst_addr;
 711	}
 712
 713	if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
 714		chan->dcmd |= DCMD_WIDTH1;
 715	else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
 716		chan->dcmd |= DCMD_WIDTH2;
 717	else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
 718		chan->dcmd |= DCMD_WIDTH4;
 719
 720	if (maxburst == 8)
 721		chan->dcmd |= DCMD_BURST8;
 722	else if (maxburst == 16)
 723		chan->dcmd |= DCMD_BURST16;
 724	else if (maxburst == 32)
 725		chan->dcmd |= DCMD_BURST32;
 726
 727	chan->dir = direction;
 728	chan->dev_addr = addr;
 
 
 
 
 
 
 729
 730	return 0;
 731}
 732
 733static int mmp_pdma_config(struct dma_chan *dchan,
 734			   struct dma_slave_config *cfg)
 735{
 736	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 737
 738	memcpy(&chan->slave_config, cfg, sizeof(*cfg));
 739	return 0;
 740}
 741
 742static int mmp_pdma_terminate_all(struct dma_chan *dchan)
 743{
 744	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 745	unsigned long flags;
 746
 747	if (!dchan)
 748		return -EINVAL;
 749
 750	disable_chan(chan->phy);
 751	mmp_pdma_free_phy(chan);
 752	spin_lock_irqsave(&chan->desc_lock, flags);
 753	mmp_pdma_free_desc_list(chan, &chan->chain_pending);
 754	mmp_pdma_free_desc_list(chan, &chan->chain_running);
 755	spin_unlock_irqrestore(&chan->desc_lock, flags);
 756	chan->idle = true;
 757
 758	return 0;
 759}
 760
 761static unsigned int mmp_pdma_residue(struct mmp_pdma_chan *chan,
 762				     dma_cookie_t cookie)
 763{
 764	struct mmp_pdma_desc_sw *sw;
 765	u32 curr, residue = 0;
 766	bool passed = false;
 767	bool cyclic = chan->cyclic_first != NULL;
 768
 769	/*
 770	 * If the channel does not have a phy pointer anymore, it has already
 771	 * been completed. Therefore, its residue is 0.
 772	 */
 773	if (!chan->phy)
 774		return 0;
 775
 776	if (chan->dir == DMA_DEV_TO_MEM)
 777		curr = readl(chan->phy->base + DTADR(chan->phy->idx));
 778	else
 779		curr = readl(chan->phy->base + DSADR(chan->phy->idx));
 780
 781	list_for_each_entry(sw, &chan->chain_running, node) {
 782		u32 start, end, len;
 783
 784		if (chan->dir == DMA_DEV_TO_MEM)
 785			start = sw->desc.dtadr;
 786		else
 787			start = sw->desc.dsadr;
 788
 789		len = sw->desc.dcmd & DCMD_LENGTH;
 790		end = start + len;
 791
 792		/*
 793		 * 'passed' will be latched once we found the descriptor which
 794		 * lies inside the boundaries of the curr pointer. All
 795		 * descriptors that occur in the list _after_ we found that
 796		 * partially handled descriptor are still to be processed and
 797		 * are hence added to the residual bytes counter.
 798		 */
 799
 800		if (passed) {
 801			residue += len;
 802		} else if (curr >= start && curr <= end) {
 803			residue += end - curr;
 804			passed = true;
 805		}
 806
 807		/*
 808		 * Descriptors that have the ENDIRQEN bit set mark the end of a
 809		 * transaction chain, and the cookie assigned with it has been
 810		 * returned previously from mmp_pdma_tx_submit().
 811		 *
 812		 * In case we have multiple transactions in the running chain,
 813		 * and the cookie does not match the one the user asked us
 814		 * about, reset the state variables and start over.
 815		 *
 816		 * This logic does not apply to cyclic transactions, where all
 817		 * descriptors have the ENDIRQEN bit set, and for which we
 818		 * can't have multiple transactions on one channel anyway.
 819		 */
 820		if (cyclic || !(sw->desc.dcmd & DCMD_ENDIRQEN))
 821			continue;
 822
 823		if (sw->async_tx.cookie == cookie) {
 824			return residue;
 825		} else {
 826			residue = 0;
 827			passed = false;
 828		}
 829	}
 830
 831	/* We should only get here in case of cyclic transactions */
 832	return residue;
 833}
 834
 835static enum dma_status mmp_pdma_tx_status(struct dma_chan *dchan,
 836					  dma_cookie_t cookie,
 837					  struct dma_tx_state *txstate)
 838{
 839	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 840	enum dma_status ret;
 841
 842	ret = dma_cookie_status(dchan, cookie, txstate);
 843	if (likely(ret != DMA_ERROR))
 844		dma_set_residue(txstate, mmp_pdma_residue(chan, cookie));
 845
 846	return ret;
 847}
 848
 849/*
 850 * mmp_pdma_issue_pending - Issue the DMA start command
 851 * pending list ==> running list
 852 */
 853static void mmp_pdma_issue_pending(struct dma_chan *dchan)
 854{
 855	struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
 856	unsigned long flags;
 857
 858	spin_lock_irqsave(&chan->desc_lock, flags);
 859	start_pending_queue(chan);
 860	spin_unlock_irqrestore(&chan->desc_lock, flags);
 861}
 862
 863/*
 864 * dma_do_tasklet
 865 * Do call back
 866 * Start pending list
 867 */
 868static void dma_do_tasklet(struct tasklet_struct *t)
 869{
 870	struct mmp_pdma_chan *chan = from_tasklet(chan, t, tasklet);
 871	struct mmp_pdma_desc_sw *desc, *_desc;
 872	LIST_HEAD(chain_cleanup);
 873	unsigned long flags;
 874	struct dmaengine_desc_callback cb;
 875
 876	if (chan->cyclic_first) {
 877		spin_lock_irqsave(&chan->desc_lock, flags);
 878		desc = chan->cyclic_first;
 879		dmaengine_desc_get_callback(&desc->async_tx, &cb);
 880		spin_unlock_irqrestore(&chan->desc_lock, flags);
 881
 882		dmaengine_desc_callback_invoke(&cb, NULL);
 883
 884		return;
 885	}
 886
 887	/* submit pending list; callback for each desc; free desc */
 888	spin_lock_irqsave(&chan->desc_lock, flags);
 889
 890	list_for_each_entry_safe(desc, _desc, &chan->chain_running, node) {
 891		/*
 892		 * move the descriptors to a temporary list so we can drop
 893		 * the lock during the entire cleanup operation
 894		 */
 895		list_move(&desc->node, &chain_cleanup);
 896
 897		/*
 898		 * Look for the first list entry which has the ENDIRQEN flag
 899		 * set. That is the descriptor we got an interrupt for, so
 900		 * complete that transaction and its cookie.
 901		 */
 902		if (desc->desc.dcmd & DCMD_ENDIRQEN) {
 903			dma_cookie_t cookie = desc->async_tx.cookie;
 904			dma_cookie_complete(&desc->async_tx);
 905			dev_dbg(chan->dev, "completed_cookie=%d\n", cookie);
 906			break;
 907		}
 908	}
 909
 910	/*
 911	 * The hardware is idle and ready for more when the
 912	 * chain_running list is empty.
 913	 */
 914	chan->idle = list_empty(&chan->chain_running);
 915
 916	/* Start any pending transactions automatically */
 917	start_pending_queue(chan);
 918	spin_unlock_irqrestore(&chan->desc_lock, flags);
 919
 920	/* Run the callback for each descriptor, in order */
 921	list_for_each_entry_safe(desc, _desc, &chain_cleanup, node) {
 922		struct dma_async_tx_descriptor *txd = &desc->async_tx;
 923
 924		/* Remove from the list of transactions */
 925		list_del(&desc->node);
 926		/* Run the link descriptor callback function */
 927		dmaengine_desc_get_callback(txd, &cb);
 928		dmaengine_desc_callback_invoke(&cb, NULL);
 929
 930		dma_pool_free(chan->desc_pool, desc, txd->phys);
 931	}
 932}
 933
 934static void mmp_pdma_remove(struct platform_device *op)
 935{
 936	struct mmp_pdma_device *pdev = platform_get_drvdata(op);
 937	struct mmp_pdma_phy *phy;
 938	int i, irq = 0, irq_num = 0;
 939
 940	if (op->dev.of_node)
 941		of_dma_controller_free(op->dev.of_node);
 942
 943	for (i = 0; i < pdev->dma_channels; i++) {
 944		if (platform_get_irq(op, i) > 0)
 945			irq_num++;
 946	}
 947
 948	if (irq_num != pdev->dma_channels) {
 949		irq = platform_get_irq(op, 0);
 950		devm_free_irq(&op->dev, irq, pdev);
 951	} else {
 952		for (i = 0; i < pdev->dma_channels; i++) {
 953			phy = &pdev->phy[i];
 954			irq = platform_get_irq(op, i);
 955			devm_free_irq(&op->dev, irq, phy);
 956		}
 957	}
 958
 959	dma_async_device_unregister(&pdev->device);
 
 960}
 961
 962static int mmp_pdma_chan_init(struct mmp_pdma_device *pdev, int idx, int irq)
 963{
 964	struct mmp_pdma_phy *phy  = &pdev->phy[idx];
 965	struct mmp_pdma_chan *chan;
 966	int ret;
 967
 968	chan = devm_kzalloc(pdev->dev, sizeof(*chan), GFP_KERNEL);
 969	if (chan == NULL)
 970		return -ENOMEM;
 971
 972	phy->idx = idx;
 973	phy->base = pdev->base;
 974
 975	if (irq) {
 976		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_chan_handler,
 977				       IRQF_SHARED, "pdma", phy);
 978		if (ret) {
 979			dev_err(pdev->dev, "channel request irq fail!\n");
 980			return ret;
 981		}
 982	}
 983
 984	spin_lock_init(&chan->desc_lock);
 985	chan->dev = pdev->dev;
 986	chan->chan.device = &pdev->device;
 987	tasklet_setup(&chan->tasklet, dma_do_tasklet);
 988	INIT_LIST_HEAD(&chan->chain_pending);
 989	INIT_LIST_HEAD(&chan->chain_running);
 990
 991	/* register virt channel to dma engine */
 992	list_add_tail(&chan->chan.device_node, &pdev->device.channels);
 993
 994	return 0;
 995}
 996
 997static const struct of_device_id mmp_pdma_dt_ids[] = {
 998	{ .compatible = "marvell,pdma-1.0", },
 999	{}
1000};
1001MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids);
1002
1003static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec,
1004					   struct of_dma *ofdma)
1005{
1006	struct mmp_pdma_device *d = ofdma->of_dma_data;
1007	struct dma_chan *chan;
1008
1009	chan = dma_get_any_slave_channel(&d->device);
1010	if (!chan)
1011		return NULL;
1012
1013	to_mmp_pdma_chan(chan)->drcmr = dma_spec->args[0];
1014
1015	return chan;
1016}
1017
1018static int mmp_pdma_probe(struct platform_device *op)
1019{
1020	struct mmp_pdma_device *pdev;
 
1021	struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
 
1022	int i, ret, irq = 0;
1023	int dma_channels = 0, irq_num = 0;
1024	const enum dma_slave_buswidth widths =
1025		DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1026		DMA_SLAVE_BUSWIDTH_4_BYTES;
1027
1028	pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1029	if (!pdev)
1030		return -ENOMEM;
1031
1032	pdev->dev = &op->dev;
1033
1034	spin_lock_init(&pdev->phy_lock);
1035
1036	pdev->base = devm_platform_ioremap_resource(op, 0);
 
1037	if (IS_ERR(pdev->base))
1038		return PTR_ERR(pdev->base);
1039
1040	if (pdev->dev->of_node) {
1041		/* Parse new and deprecated dma-channels properties */
1042		if (of_property_read_u32(pdev->dev->of_node, "dma-channels",
1043					 &dma_channels))
1044			of_property_read_u32(pdev->dev->of_node, "#dma-channels",
1045					     &dma_channels);
1046	} else if (pdata && pdata->dma_channels) {
1047		dma_channels = pdata->dma_channels;
1048	} else {
1049		dma_channels = 32;	/* default 32 channel */
1050	}
1051	pdev->dma_channels = dma_channels;
1052
1053	for (i = 0; i < dma_channels; i++) {
1054		if (platform_get_irq_optional(op, i) > 0)
1055			irq_num++;
1056	}
1057
1058	pdev->phy = devm_kcalloc(pdev->dev, dma_channels, sizeof(*pdev->phy),
1059				 GFP_KERNEL);
1060	if (pdev->phy == NULL)
1061		return -ENOMEM;
1062
1063	INIT_LIST_HEAD(&pdev->device.channels);
1064
1065	if (irq_num != dma_channels) {
1066		/* all chan share one irq, demux inside */
1067		irq = platform_get_irq(op, 0);
1068		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_int_handler,
1069				       IRQF_SHARED, "pdma", pdev);
1070		if (ret)
1071			return ret;
1072	}
1073
1074	for (i = 0; i < dma_channels; i++) {
1075		irq = (irq_num != dma_channels) ? 0 : platform_get_irq(op, i);
1076		ret = mmp_pdma_chan_init(pdev, i, irq);
1077		if (ret)
1078			return ret;
1079	}
1080
1081	dma_cap_set(DMA_SLAVE, pdev->device.cap_mask);
1082	dma_cap_set(DMA_MEMCPY, pdev->device.cap_mask);
1083	dma_cap_set(DMA_CYCLIC, pdev->device.cap_mask);
1084	dma_cap_set(DMA_PRIVATE, pdev->device.cap_mask);
1085	pdev->device.dev = &op->dev;
1086	pdev->device.device_alloc_chan_resources = mmp_pdma_alloc_chan_resources;
1087	pdev->device.device_free_chan_resources = mmp_pdma_free_chan_resources;
1088	pdev->device.device_tx_status = mmp_pdma_tx_status;
1089	pdev->device.device_prep_dma_memcpy = mmp_pdma_prep_memcpy;
1090	pdev->device.device_prep_slave_sg = mmp_pdma_prep_slave_sg;
1091	pdev->device.device_prep_dma_cyclic = mmp_pdma_prep_dma_cyclic;
1092	pdev->device.device_issue_pending = mmp_pdma_issue_pending;
1093	pdev->device.device_config = mmp_pdma_config;
1094	pdev->device.device_terminate_all = mmp_pdma_terminate_all;
1095	pdev->device.copy_align = DMAENGINE_ALIGN_8_BYTES;
1096	pdev->device.src_addr_widths = widths;
1097	pdev->device.dst_addr_widths = widths;
1098	pdev->device.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1099	pdev->device.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1100
1101	if (pdev->dev->coherent_dma_mask)
1102		dma_set_mask(pdev->dev, pdev->dev->coherent_dma_mask);
1103	else
1104		dma_set_mask(pdev->dev, DMA_BIT_MASK(64));
1105
1106	ret = dma_async_device_register(&pdev->device);
1107	if (ret) {
1108		dev_err(pdev->device.dev, "unable to register\n");
1109		return ret;
1110	}
1111
1112	if (op->dev.of_node) {
1113		/* Device-tree DMA controller registration */
1114		ret = of_dma_controller_register(op->dev.of_node,
1115						 mmp_pdma_dma_xlate, pdev);
1116		if (ret < 0) {
1117			dev_err(&op->dev, "of_dma_controller_register failed\n");
1118			dma_async_device_unregister(&pdev->device);
1119			return ret;
1120		}
1121	}
1122
1123	platform_set_drvdata(op, pdev);
1124	dev_info(pdev->device.dev, "initialized %d channels\n", dma_channels);
1125	return 0;
1126}
1127
1128static const struct platform_device_id mmp_pdma_id_table[] = {
1129	{ "mmp-pdma", },
1130	{ },
1131};
1132
1133static struct platform_driver mmp_pdma_driver = {
1134	.driver		= {
1135		.name	= "mmp-pdma",
1136		.of_match_table = mmp_pdma_dt_ids,
1137	},
1138	.id_table	= mmp_pdma_id_table,
1139	.probe		= mmp_pdma_probe,
1140	.remove_new	= mmp_pdma_remove,
1141};
 
 
 
 
 
 
 
 
 
 
 
 
 
1142
1143module_platform_driver(mmp_pdma_driver);
1144
1145MODULE_DESCRIPTION("MARVELL MMP Peripheral DMA Driver");
1146MODULE_AUTHOR("Marvell International Ltd.");
1147MODULE_LICENSE("GPL v2");
v5.4
   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
 949	for (i = 0; i < pdev->dma_channels; i++) {
 950		if (platform_get_irq(op, i) > 0)
 951			irq_num++;
 952	}
 953
 954	if (irq_num != pdev->dma_channels) {
 955		irq = platform_get_irq(op, 0);
 956		devm_free_irq(&op->dev, irq, pdev);
 957	} else {
 958		for (i = 0; i < pdev->dma_channels; i++) {
 959			phy = &pdev->phy[i];
 960			irq = platform_get_irq(op, i);
 961			devm_free_irq(&op->dev, irq, phy);
 962		}
 963	}
 964
 965	dma_async_device_unregister(&pdev->device);
 966	return 0;
 967}
 968
 969static int mmp_pdma_chan_init(struct mmp_pdma_device *pdev, int idx, int irq)
 970{
 971	struct mmp_pdma_phy *phy  = &pdev->phy[idx];
 972	struct mmp_pdma_chan *chan;
 973	int ret;
 974
 975	chan = devm_kzalloc(pdev->dev, sizeof(*chan), GFP_KERNEL);
 976	if (chan == NULL)
 977		return -ENOMEM;
 978
 979	phy->idx = idx;
 980	phy->base = pdev->base;
 981
 982	if (irq) {
 983		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_chan_handler,
 984				       IRQF_SHARED, "pdma", phy);
 985		if (ret) {
 986			dev_err(pdev->dev, "channel request irq fail!\n");
 987			return ret;
 988		}
 989	}
 990
 991	spin_lock_init(&chan->desc_lock);
 992	chan->dev = pdev->dev;
 993	chan->chan.device = &pdev->device;
 994	tasklet_init(&chan->tasklet, dma_do_tasklet, (unsigned long)chan);
 995	INIT_LIST_HEAD(&chan->chain_pending);
 996	INIT_LIST_HEAD(&chan->chain_running);
 997
 998	/* register virt channel to dma engine */
 999	list_add_tail(&chan->chan.device_node, &pdev->device.channels);
1000
1001	return 0;
1002}
1003
1004static const struct of_device_id mmp_pdma_dt_ids[] = {
1005	{ .compatible = "marvell,pdma-1.0", },
1006	{}
1007};
1008MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids);
1009
1010static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec,
1011					   struct of_dma *ofdma)
1012{
1013	struct mmp_pdma_device *d = ofdma->of_dma_data;
1014	struct dma_chan *chan;
1015
1016	chan = dma_get_any_slave_channel(&d->device);
1017	if (!chan)
1018		return NULL;
1019
1020	to_mmp_pdma_chan(chan)->drcmr = dma_spec->args[0];
1021
1022	return chan;
1023}
1024
1025static int mmp_pdma_probe(struct platform_device *op)
1026{
1027	struct mmp_pdma_device *pdev;
1028	const struct of_device_id *of_id;
1029	struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1030	struct resource *iores;
1031	int i, ret, irq = 0;
1032	int dma_channels = 0, irq_num = 0;
1033	const enum dma_slave_buswidth widths =
1034		DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1035		DMA_SLAVE_BUSWIDTH_4_BYTES;
1036
1037	pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1038	if (!pdev)
1039		return -ENOMEM;
1040
1041	pdev->dev = &op->dev;
1042
1043	spin_lock_init(&pdev->phy_lock);
1044
1045	iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1046	pdev->base = devm_ioremap_resource(pdev->dev, iores);
1047	if (IS_ERR(pdev->base))
1048		return PTR_ERR(pdev->base);
1049
1050	of_id = of_match_device(mmp_pdma_dt_ids, pdev->dev);
1051	if (of_id)
1052		of_property_read_u32(pdev->dev->of_node, "#dma-channels",
1053				     &dma_channels);
1054	else if (pdata && pdata->dma_channels)
 
 
1055		dma_channels = pdata->dma_channels;
1056	else
1057		dma_channels = 32;	/* default 32 channel */
 
1058	pdev->dma_channels = dma_channels;
1059
1060	for (i = 0; i < dma_channels; i++) {
1061		if (platform_get_irq(op, i) > 0)
1062			irq_num++;
1063	}
1064
1065	pdev->phy = devm_kcalloc(pdev->dev, dma_channels, sizeof(*pdev->phy),
1066				 GFP_KERNEL);
1067	if (pdev->phy == NULL)
1068		return -ENOMEM;
1069
1070	INIT_LIST_HEAD(&pdev->device.channels);
1071
1072	if (irq_num != dma_channels) {
1073		/* all chan share one irq, demux inside */
1074		irq = platform_get_irq(op, 0);
1075		ret = devm_request_irq(pdev->dev, irq, mmp_pdma_int_handler,
1076				       IRQF_SHARED, "pdma", pdev);
1077		if (ret)
1078			return ret;
1079	}
1080
1081	for (i = 0; i < dma_channels; i++) {
1082		irq = (irq_num != dma_channels) ? 0 : platform_get_irq(op, i);
1083		ret = mmp_pdma_chan_init(pdev, i, irq);
1084		if (ret)
1085			return ret;
1086	}
1087
1088	dma_cap_set(DMA_SLAVE, pdev->device.cap_mask);
1089	dma_cap_set(DMA_MEMCPY, pdev->device.cap_mask);
1090	dma_cap_set(DMA_CYCLIC, pdev->device.cap_mask);
1091	dma_cap_set(DMA_PRIVATE, pdev->device.cap_mask);
1092	pdev->device.dev = &op->dev;
1093	pdev->device.device_alloc_chan_resources = mmp_pdma_alloc_chan_resources;
1094	pdev->device.device_free_chan_resources = mmp_pdma_free_chan_resources;
1095	pdev->device.device_tx_status = mmp_pdma_tx_status;
1096	pdev->device.device_prep_dma_memcpy = mmp_pdma_prep_memcpy;
1097	pdev->device.device_prep_slave_sg = mmp_pdma_prep_slave_sg;
1098	pdev->device.device_prep_dma_cyclic = mmp_pdma_prep_dma_cyclic;
1099	pdev->device.device_issue_pending = mmp_pdma_issue_pending;
1100	pdev->device.device_config = mmp_pdma_config;
1101	pdev->device.device_terminate_all = mmp_pdma_terminate_all;
1102	pdev->device.copy_align = DMAENGINE_ALIGN_8_BYTES;
1103	pdev->device.src_addr_widths = widths;
1104	pdev->device.dst_addr_widths = widths;
1105	pdev->device.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1106	pdev->device.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1107
1108	if (pdev->dev->coherent_dma_mask)
1109		dma_set_mask(pdev->dev, pdev->dev->coherent_dma_mask);
1110	else
1111		dma_set_mask(pdev->dev, DMA_BIT_MASK(64));
1112
1113	ret = dma_async_device_register(&pdev->device);
1114	if (ret) {
1115		dev_err(pdev->device.dev, "unable to register\n");
1116		return ret;
1117	}
1118
1119	if (op->dev.of_node) {
1120		/* Device-tree DMA controller registration */
1121		ret = of_dma_controller_register(op->dev.of_node,
1122						 mmp_pdma_dma_xlate, pdev);
1123		if (ret < 0) {
1124			dev_err(&op->dev, "of_dma_controller_register failed\n");
 
1125			return ret;
1126		}
1127	}
1128
1129	platform_set_drvdata(op, pdev);
1130	dev_info(pdev->device.dev, "initialized %d channels\n", dma_channels);
1131	return 0;
1132}
1133
1134static const struct platform_device_id mmp_pdma_id_table[] = {
1135	{ "mmp-pdma", },
1136	{ },
1137};
1138
1139static struct platform_driver mmp_pdma_driver = {
1140	.driver		= {
1141		.name	= "mmp-pdma",
1142		.of_match_table = mmp_pdma_dt_ids,
1143	},
1144	.id_table	= mmp_pdma_id_table,
1145	.probe		= mmp_pdma_probe,
1146	.remove		= mmp_pdma_remove,
1147};
1148
1149bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param)
1150{
1151	struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan);
1152
1153	if (chan->device->dev->driver != &mmp_pdma_driver.driver)
1154		return false;
1155
1156	c->drcmr = *(unsigned int *)param;
1157
1158	return true;
1159}
1160EXPORT_SYMBOL_GPL(mmp_pdma_filter_fn);
1161
1162module_platform_driver(mmp_pdma_driver);
1163
1164MODULE_DESCRIPTION("MARVELL MMP Peripheral DMA Driver");
1165MODULE_AUTHOR("Marvell International Ltd.");
1166MODULE_LICENSE("GPL v2");