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