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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *
   4 * Copyright (C) STMicroelectronics SA 2017
   5 * Author(s): M'boumba Cedric Madianga <cedric.madianga@gmail.com>
   6 *            Pierre-Yves Mordret <pierre-yves.mordret@st.com>
   7 *
   8 * Driver for STM32 MDMA controller
   9 *
  10 * Inspired by stm32-dma.c and dma-jz4780.c
  11 */
  12
  13#include <linux/bitfield.h>
  14#include <linux/clk.h>
  15#include <linux/delay.h>
  16#include <linux/dmaengine.h>
  17#include <linux/dma-mapping.h>
  18#include <linux/dmapool.h>
  19#include <linux/err.h>
  20#include <linux/init.h>
  21#include <linux/iopoll.h>
  22#include <linux/jiffies.h>
  23#include <linux/list.h>
  24#include <linux/log2.h>
  25#include <linux/module.h>
  26#include <linux/of.h>
  27#include <linux/of_dma.h>
  28#include <linux/platform_device.h>
  29#include <linux/pm_runtime.h>
  30#include <linux/reset.h>
  31#include <linux/slab.h>
  32
  33#include "virt-dma.h"
  34
  35#define STM32_MDMA_GISR0		0x0000 /* MDMA Int Status Reg 1 */
  36
  37/* MDMA Channel x interrupt/status register */
  38#define STM32_MDMA_CISR(x)		(0x40 + 0x40 * (x)) /* x = 0..62 */
  39#define STM32_MDMA_CISR_CRQA		BIT(16)
  40#define STM32_MDMA_CISR_TCIF		BIT(4)
  41#define STM32_MDMA_CISR_BTIF		BIT(3)
  42#define STM32_MDMA_CISR_BRTIF		BIT(2)
  43#define STM32_MDMA_CISR_CTCIF		BIT(1)
  44#define STM32_MDMA_CISR_TEIF		BIT(0)
  45
  46/* MDMA Channel x interrupt flag clear register */
  47#define STM32_MDMA_CIFCR(x)		(0x44 + 0x40 * (x))
  48#define STM32_MDMA_CIFCR_CLTCIF		BIT(4)
  49#define STM32_MDMA_CIFCR_CBTIF		BIT(3)
  50#define STM32_MDMA_CIFCR_CBRTIF		BIT(2)
  51#define STM32_MDMA_CIFCR_CCTCIF		BIT(1)
  52#define STM32_MDMA_CIFCR_CTEIF		BIT(0)
  53#define STM32_MDMA_CIFCR_CLEAR_ALL	(STM32_MDMA_CIFCR_CLTCIF \
  54					| STM32_MDMA_CIFCR_CBTIF \
  55					| STM32_MDMA_CIFCR_CBRTIF \
  56					| STM32_MDMA_CIFCR_CCTCIF \
  57					| STM32_MDMA_CIFCR_CTEIF)
  58
  59/* MDMA Channel x error status register */
  60#define STM32_MDMA_CESR(x)		(0x48 + 0x40 * (x))
  61#define STM32_MDMA_CESR_BSE		BIT(11)
  62#define STM32_MDMA_CESR_ASR		BIT(10)
  63#define STM32_MDMA_CESR_TEMD		BIT(9)
  64#define STM32_MDMA_CESR_TELD		BIT(8)
  65#define STM32_MDMA_CESR_TED		BIT(7)
  66#define STM32_MDMA_CESR_TEA_MASK	GENMASK(6, 0)
  67
  68/* MDMA Channel x control register */
  69#define STM32_MDMA_CCR(x)		(0x4C + 0x40 * (x))
  70#define STM32_MDMA_CCR_SWRQ		BIT(16)
  71#define STM32_MDMA_CCR_WEX		BIT(14)
  72#define STM32_MDMA_CCR_HEX		BIT(13)
  73#define STM32_MDMA_CCR_BEX		BIT(12)
  74#define STM32_MDMA_CCR_SM		BIT(8)
  75#define STM32_MDMA_CCR_PL_MASK		GENMASK(7, 6)
  76#define STM32_MDMA_CCR_PL(n)		FIELD_PREP(STM32_MDMA_CCR_PL_MASK, (n))
  77#define STM32_MDMA_CCR_TCIE		BIT(5)
  78#define STM32_MDMA_CCR_BTIE		BIT(4)
  79#define STM32_MDMA_CCR_BRTIE		BIT(3)
  80#define STM32_MDMA_CCR_CTCIE		BIT(2)
  81#define STM32_MDMA_CCR_TEIE		BIT(1)
  82#define STM32_MDMA_CCR_EN		BIT(0)
  83#define STM32_MDMA_CCR_IRQ_MASK		(STM32_MDMA_CCR_TCIE \
  84					| STM32_MDMA_CCR_BTIE \
  85					| STM32_MDMA_CCR_BRTIE \
  86					| STM32_MDMA_CCR_CTCIE \
  87					| STM32_MDMA_CCR_TEIE)
  88
  89/* MDMA Channel x transfer configuration register */
  90#define STM32_MDMA_CTCR(x)		(0x50 + 0x40 * (x))
  91#define STM32_MDMA_CTCR_BWM		BIT(31)
  92#define STM32_MDMA_CTCR_SWRM		BIT(30)
  93#define STM32_MDMA_CTCR_TRGM_MSK	GENMASK(29, 28)
  94#define STM32_MDMA_CTCR_TRGM(n)		FIELD_PREP(STM32_MDMA_CTCR_TRGM_MSK, (n))
  95#define STM32_MDMA_CTCR_TRGM_GET(n)	FIELD_GET(STM32_MDMA_CTCR_TRGM_MSK, (n))
  96#define STM32_MDMA_CTCR_PAM_MASK	GENMASK(27, 26)
  97#define STM32_MDMA_CTCR_PAM(n)		FIELD_PREP(STM32_MDMA_CTCR_PAM_MASK, (n))
  98#define STM32_MDMA_CTCR_PKE		BIT(25)
  99#define STM32_MDMA_CTCR_TLEN_MSK	GENMASK(24, 18)
 100#define STM32_MDMA_CTCR_TLEN(n)		FIELD_PREP(STM32_MDMA_CTCR_TLEN_MSK, (n))
 101#define STM32_MDMA_CTCR_TLEN_GET(n)	FIELD_GET(STM32_MDMA_CTCR_TLEN_MSK, (n))
 102#define STM32_MDMA_CTCR_LEN2_MSK	GENMASK(25, 18)
 103#define STM32_MDMA_CTCR_LEN2(n)		FIELD_PREP(STM32_MDMA_CTCR_LEN2_MSK, (n))
 104#define STM32_MDMA_CTCR_LEN2_GET(n)	FIELD_GET(STM32_MDMA_CTCR_LEN2_MSK, (n))
 105#define STM32_MDMA_CTCR_DBURST_MASK	GENMASK(17, 15)
 106#define STM32_MDMA_CTCR_DBURST(n)	FIELD_PREP(STM32_MDMA_CTCR_DBURST_MASK, (n))
 107#define STM32_MDMA_CTCR_SBURST_MASK	GENMASK(14, 12)
 108#define STM32_MDMA_CTCR_SBURST(n)	FIELD_PREP(STM32_MDMA_CTCR_SBURST_MASK, (n))
 109#define STM32_MDMA_CTCR_DINCOS_MASK	GENMASK(11, 10)
 110#define STM32_MDMA_CTCR_DINCOS(n)	FIELD_PREP(STM32_MDMA_CTCR_DINCOS_MASK, (n))
 111#define STM32_MDMA_CTCR_SINCOS_MASK	GENMASK(9, 8)
 112#define STM32_MDMA_CTCR_SINCOS(n)	FIELD_PREP(STM32_MDMA_CTCR_SINCOS_MASK, (n))
 113#define STM32_MDMA_CTCR_DSIZE_MASK	GENMASK(7, 6)
 114#define STM32_MDMA_CTCR_DSIZE(n)	FIELD_PREP(STM32_MDMA_CTCR_DSIZE_MASK, (n))
 115#define STM32_MDMA_CTCR_SSIZE_MASK	GENMASK(5, 4)
 116#define STM32_MDMA_CTCR_SSIZE(n)	FIELD_PREP(STM32_MDMA_CTCR_SSIZE_MASK, (n))
 117#define STM32_MDMA_CTCR_DINC_MASK	GENMASK(3, 2)
 118#define STM32_MDMA_CTCR_DINC(n)		FIELD_PREP(STM32_MDMA_CTCR_DINC_MASK, (n))
 119#define STM32_MDMA_CTCR_SINC_MASK	GENMASK(1, 0)
 120#define STM32_MDMA_CTCR_SINC(n)		FIELD_PREP(STM32_MDMA_CTCR_SINC_MASK, (n))
 121#define STM32_MDMA_CTCR_CFG_MASK	(STM32_MDMA_CTCR_SINC_MASK \
 122					| STM32_MDMA_CTCR_DINC_MASK \
 123					| STM32_MDMA_CTCR_SINCOS_MASK \
 124					| STM32_MDMA_CTCR_DINCOS_MASK \
 125					| STM32_MDMA_CTCR_LEN2_MSK \
 126					| STM32_MDMA_CTCR_TRGM_MSK)
 127
 128/* MDMA Channel x block number of data register */
 129#define STM32_MDMA_CBNDTR(x)		(0x54 + 0x40 * (x))
 130#define STM32_MDMA_CBNDTR_BRC_MK	GENMASK(31, 20)
 131#define STM32_MDMA_CBNDTR_BRC(n)	FIELD_PREP(STM32_MDMA_CBNDTR_BRC_MK, (n))
 132#define STM32_MDMA_CBNDTR_BRC_GET(n)	FIELD_GET(STM32_MDMA_CBNDTR_BRC_MK, (n))
 133
 134#define STM32_MDMA_CBNDTR_BRDUM		BIT(19)
 135#define STM32_MDMA_CBNDTR_BRSUM		BIT(18)
 136#define STM32_MDMA_CBNDTR_BNDT_MASK	GENMASK(16, 0)
 137#define STM32_MDMA_CBNDTR_BNDT(n)	FIELD_PREP(STM32_MDMA_CBNDTR_BNDT_MASK, (n))
 138
 139/* MDMA Channel x source address register */
 140#define STM32_MDMA_CSAR(x)		(0x58 + 0x40 * (x))
 141
 142/* MDMA Channel x destination address register */
 143#define STM32_MDMA_CDAR(x)		(0x5C + 0x40 * (x))
 144
 145/* MDMA Channel x block repeat address update register */
 146#define STM32_MDMA_CBRUR(x)		(0x60 + 0x40 * (x))
 147#define STM32_MDMA_CBRUR_DUV_MASK	GENMASK(31, 16)
 148#define STM32_MDMA_CBRUR_DUV(n)		FIELD_PREP(STM32_MDMA_CBRUR_DUV_MASK, (n))
 149#define STM32_MDMA_CBRUR_SUV_MASK	GENMASK(15, 0)
 150#define STM32_MDMA_CBRUR_SUV(n)		FIELD_PREP(STM32_MDMA_CBRUR_SUV_MASK, (n))
 151
 152/* MDMA Channel x link address register */
 153#define STM32_MDMA_CLAR(x)		(0x64 + 0x40 * (x))
 154
 155/* MDMA Channel x trigger and bus selection register */
 156#define STM32_MDMA_CTBR(x)		(0x68 + 0x40 * (x))
 157#define STM32_MDMA_CTBR_DBUS		BIT(17)
 158#define STM32_MDMA_CTBR_SBUS		BIT(16)
 159#define STM32_MDMA_CTBR_TSEL_MASK	GENMASK(5, 0)
 160#define STM32_MDMA_CTBR_TSEL(n)		FIELD_PREP(STM32_MDMA_CTBR_TSEL_MASK, (n))
 161
 162/* MDMA Channel x mask address register */
 163#define STM32_MDMA_CMAR(x)		(0x70 + 0x40 * (x))
 164
 165/* MDMA Channel x mask data register */
 166#define STM32_MDMA_CMDR(x)		(0x74 + 0x40 * (x))
 167
 168#define STM32_MDMA_MAX_BUF_LEN		128
 169#define STM32_MDMA_MAX_BLOCK_LEN	65536
 170#define STM32_MDMA_MAX_CHANNELS		32
 171#define STM32_MDMA_MAX_REQUESTS		256
 172#define STM32_MDMA_MAX_BURST		128
 173#define STM32_MDMA_VERY_HIGH_PRIORITY	0x3
 174
 175enum stm32_mdma_trigger_mode {
 176	STM32_MDMA_BUFFER,
 177	STM32_MDMA_BLOCK,
 178	STM32_MDMA_BLOCK_REP,
 179	STM32_MDMA_LINKED_LIST,
 180};
 181
 182enum stm32_mdma_width {
 183	STM32_MDMA_BYTE,
 184	STM32_MDMA_HALF_WORD,
 185	STM32_MDMA_WORD,
 186	STM32_MDMA_DOUBLE_WORD,
 187};
 188
 189enum stm32_mdma_inc_mode {
 190	STM32_MDMA_FIXED = 0,
 191	STM32_MDMA_INC = 2,
 192	STM32_MDMA_DEC = 3,
 193};
 194
 195struct stm32_mdma_chan_config {
 196	u32 request;
 197	u32 priority_level;
 198	u32 transfer_config;
 199	u32 mask_addr;
 200	u32 mask_data;
 201	bool m2m_hw; /* True when MDMA is triggered by STM32 DMA */
 202};
 203
 204struct stm32_mdma_hwdesc {
 205	u32 ctcr;
 206	u32 cbndtr;
 207	u32 csar;
 208	u32 cdar;
 209	u32 cbrur;
 210	u32 clar;
 211	u32 ctbr;
 212	u32 dummy;
 213	u32 cmar;
 214	u32 cmdr;
 215} __aligned(64);
 216
 217struct stm32_mdma_desc_node {
 218	struct stm32_mdma_hwdesc *hwdesc;
 219	dma_addr_t hwdesc_phys;
 220};
 221
 222struct stm32_mdma_desc {
 223	struct virt_dma_desc vdesc;
 224	u32 ccr;
 225	bool cyclic;
 226	u32 count;
 227	struct stm32_mdma_desc_node node[] __counted_by(count);
 228};
 229
 230struct stm32_mdma_dma_config {
 231	u32 request;	/* STM32 DMA channel stream id, triggering MDMA */
 232	u32 cmar;	/* STM32 DMA interrupt flag clear register address */
 233	u32 cmdr;	/* STM32 DMA Transfer Complete flag */
 234};
 235
 236struct stm32_mdma_chan {
 237	struct virt_dma_chan vchan;
 238	struct dma_pool *desc_pool;
 239	u32 id;
 240	struct stm32_mdma_desc *desc;
 241	u32 curr_hwdesc;
 242	struct dma_slave_config dma_config;
 243	struct stm32_mdma_chan_config chan_config;
 244	bool busy;
 245	u32 mem_burst;
 246	u32 mem_width;
 247};
 248
 249struct stm32_mdma_device {
 250	struct dma_device ddev;
 251	void __iomem *base;
 252	struct clk *clk;
 253	int irq;
 254	u32 nr_channels;
 255	u32 nr_requests;
 256	u32 nr_ahb_addr_masks;
 257	u32 chan_reserved;
 258	struct stm32_mdma_chan chan[STM32_MDMA_MAX_CHANNELS];
 259	u32 ahb_addr_masks[] __counted_by(nr_ahb_addr_masks);
 260};
 261
 262static struct stm32_mdma_device *stm32_mdma_get_dev(
 263	struct stm32_mdma_chan *chan)
 264{
 265	return container_of(chan->vchan.chan.device, struct stm32_mdma_device,
 266			    ddev);
 267}
 268
 269static struct stm32_mdma_chan *to_stm32_mdma_chan(struct dma_chan *c)
 270{
 271	return container_of(c, struct stm32_mdma_chan, vchan.chan);
 272}
 273
 274static struct stm32_mdma_desc *to_stm32_mdma_desc(struct virt_dma_desc *vdesc)
 275{
 276	return container_of(vdesc, struct stm32_mdma_desc, vdesc);
 277}
 278
 279static struct device *chan2dev(struct stm32_mdma_chan *chan)
 280{
 281	return &chan->vchan.chan.dev->device;
 282}
 283
 284static struct device *mdma2dev(struct stm32_mdma_device *mdma_dev)
 285{
 286	return mdma_dev->ddev.dev;
 287}
 288
 289static u32 stm32_mdma_read(struct stm32_mdma_device *dmadev, u32 reg)
 290{
 291	return readl_relaxed(dmadev->base + reg);
 292}
 293
 294static void stm32_mdma_write(struct stm32_mdma_device *dmadev, u32 reg, u32 val)
 295{
 296	writel_relaxed(val, dmadev->base + reg);
 297}
 298
 299static void stm32_mdma_set_bits(struct stm32_mdma_device *dmadev, u32 reg,
 300				u32 mask)
 301{
 302	void __iomem *addr = dmadev->base + reg;
 303
 304	writel_relaxed(readl_relaxed(addr) | mask, addr);
 305}
 306
 307static void stm32_mdma_clr_bits(struct stm32_mdma_device *dmadev, u32 reg,
 308				u32 mask)
 309{
 310	void __iomem *addr = dmadev->base + reg;
 311
 312	writel_relaxed(readl_relaxed(addr) & ~mask, addr);
 313}
 314
 315static struct stm32_mdma_desc *stm32_mdma_alloc_desc(
 316		struct stm32_mdma_chan *chan, u32 count)
 317{
 318	struct stm32_mdma_desc *desc;
 319	int i;
 320
 321	desc = kzalloc(struct_size(desc, node, count), GFP_NOWAIT);
 322	if (!desc)
 323		return NULL;
 324	desc->count = count;
 325
 326	for (i = 0; i < count; i++) {
 327		desc->node[i].hwdesc =
 328			dma_pool_alloc(chan->desc_pool, GFP_NOWAIT,
 329				       &desc->node[i].hwdesc_phys);
 330		if (!desc->node[i].hwdesc)
 331			goto err;
 332	}
 333
 334	return desc;
 335
 336err:
 337	dev_err(chan2dev(chan), "Failed to allocate descriptor\n");
 338	while (--i >= 0)
 339		dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
 340			      desc->node[i].hwdesc_phys);
 341	kfree(desc);
 342	return NULL;
 343}
 344
 345static void stm32_mdma_desc_free(struct virt_dma_desc *vdesc)
 346{
 347	struct stm32_mdma_desc *desc = to_stm32_mdma_desc(vdesc);
 348	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(vdesc->tx.chan);
 349	int i;
 350
 351	for (i = 0; i < desc->count; i++)
 352		dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
 353			      desc->node[i].hwdesc_phys);
 354	kfree(desc);
 355}
 356
 357static int stm32_mdma_get_width(struct stm32_mdma_chan *chan,
 358				enum dma_slave_buswidth width)
 359{
 360	switch (width) {
 361	case DMA_SLAVE_BUSWIDTH_1_BYTE:
 362	case DMA_SLAVE_BUSWIDTH_2_BYTES:
 363	case DMA_SLAVE_BUSWIDTH_4_BYTES:
 364	case DMA_SLAVE_BUSWIDTH_8_BYTES:
 365		return ffs(width) - 1;
 366	default:
 367		dev_err(chan2dev(chan), "Dma bus width %i not supported\n",
 368			width);
 369		return -EINVAL;
 370	}
 371}
 372
 373static enum dma_slave_buswidth stm32_mdma_get_max_width(dma_addr_t addr,
 374							u32 buf_len, u32 tlen)
 375{
 376	enum dma_slave_buswidth max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
 377
 378	for (max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
 379	     max_width > DMA_SLAVE_BUSWIDTH_1_BYTE;
 380	     max_width >>= 1) {
 381		/*
 382		 * Address and buffer length both have to be aligned on
 383		 * bus width
 384		 */
 385		if ((((buf_len | addr) & (max_width - 1)) == 0) &&
 386		    tlen >= max_width)
 387			break;
 388	}
 389
 390	return max_width;
 391}
 392
 393static u32 stm32_mdma_get_best_burst(u32 buf_len, u32 tlen, u32 max_burst,
 394				     enum dma_slave_buswidth width)
 395{
 396	u32 best_burst;
 397
 398	best_burst = min((u32)1 << __ffs(tlen | buf_len),
 399			 max_burst * width) / width;
 400
 401	return (best_burst > 0) ? best_burst : 1;
 402}
 403
 404static int stm32_mdma_disable_chan(struct stm32_mdma_chan *chan)
 405{
 406	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
 407	u32 ccr, cisr, id, reg;
 408	int ret;
 409
 410	id = chan->id;
 411	reg = STM32_MDMA_CCR(id);
 412
 413	/* Disable interrupts */
 414	stm32_mdma_clr_bits(dmadev, reg, STM32_MDMA_CCR_IRQ_MASK);
 415
 416	ccr = stm32_mdma_read(dmadev, reg);
 417	if (ccr & STM32_MDMA_CCR_EN) {
 418		stm32_mdma_clr_bits(dmadev, reg, STM32_MDMA_CCR_EN);
 419
 420		/* Ensure that any ongoing transfer has been completed */
 421		ret = readl_relaxed_poll_timeout_atomic(
 422				dmadev->base + STM32_MDMA_CISR(id), cisr,
 423				(cisr & STM32_MDMA_CISR_CTCIF), 10, 1000);
 424		if (ret) {
 425			dev_err(chan2dev(chan), "%s: timeout!\n", __func__);
 426			return -EBUSY;
 427		}
 428	}
 429
 430	return 0;
 431}
 432
 433static void stm32_mdma_stop(struct stm32_mdma_chan *chan)
 434{
 435	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
 436	u32 status;
 437	int ret;
 438
 439	/* Disable DMA */
 440	ret = stm32_mdma_disable_chan(chan);
 441	if (ret < 0)
 442		return;
 443
 444	/* Clear interrupt status if it is there */
 445	status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id));
 446	if (status) {
 447		dev_dbg(chan2dev(chan), "%s(): clearing interrupt: 0x%08x\n",
 448			__func__, status);
 449		stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(chan->id), status);
 450	}
 451
 452	chan->busy = false;
 453}
 454
 455static void stm32_mdma_set_bus(struct stm32_mdma_device *dmadev, u32 *ctbr,
 456			       u32 ctbr_mask, u32 src_addr)
 457{
 458	u32 mask;
 459	int i;
 460
 461	/* Check if memory device is on AHB or AXI */
 462	*ctbr &= ~ctbr_mask;
 463	mask = src_addr & 0xF0000000;
 464	for (i = 0; i < dmadev->nr_ahb_addr_masks; i++) {
 465		if (mask == dmadev->ahb_addr_masks[i]) {
 466			*ctbr |= ctbr_mask;
 467			break;
 468		}
 469	}
 470}
 471
 472static int stm32_mdma_set_xfer_param(struct stm32_mdma_chan *chan,
 473				     enum dma_transfer_direction direction,
 474				     u32 *mdma_ccr, u32 *mdma_ctcr,
 475				     u32 *mdma_ctbr, dma_addr_t addr,
 476				     u32 buf_len)
 477{
 478	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
 479	struct stm32_mdma_chan_config *chan_config = &chan->chan_config;
 480	enum dma_slave_buswidth src_addr_width, dst_addr_width;
 481	phys_addr_t src_addr, dst_addr;
 482	int src_bus_width, dst_bus_width;
 483	u32 src_maxburst, dst_maxburst, src_best_burst, dst_best_burst;
 484	u32 ccr, ctcr, ctbr, tlen;
 485
 486	src_addr_width = chan->dma_config.src_addr_width;
 487	dst_addr_width = chan->dma_config.dst_addr_width;
 488	src_maxburst = chan->dma_config.src_maxburst;
 489	dst_maxburst = chan->dma_config.dst_maxburst;
 490
 491	ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)) & ~STM32_MDMA_CCR_EN;
 492	ctcr = stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id));
 493	ctbr = stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id));
 494
 495	/* Enable HW request mode */
 496	ctcr &= ~STM32_MDMA_CTCR_SWRM;
 497
 498	/* Set DINC, SINC, DINCOS, SINCOS, TRGM and TLEN retrieve from DT */
 499	ctcr &= ~STM32_MDMA_CTCR_CFG_MASK;
 500	ctcr |= chan_config->transfer_config & STM32_MDMA_CTCR_CFG_MASK;
 501
 502	/*
 503	 * For buffer transfer length (TLEN) we have to set
 504	 * the number of bytes - 1 in CTCR register
 505	 */
 506	tlen = STM32_MDMA_CTCR_LEN2_GET(ctcr);
 507	ctcr &= ~STM32_MDMA_CTCR_LEN2_MSK;
 508	ctcr |= STM32_MDMA_CTCR_TLEN((tlen - 1));
 509
 510	/* Disable Pack Enable */
 511	ctcr &= ~STM32_MDMA_CTCR_PKE;
 512
 513	/* Check burst size constraints */
 514	if (src_maxburst * src_addr_width > STM32_MDMA_MAX_BURST ||
 515	    dst_maxburst * dst_addr_width > STM32_MDMA_MAX_BURST) {
 516		dev_err(chan2dev(chan),
 517			"burst size * bus width higher than %d bytes\n",
 518			STM32_MDMA_MAX_BURST);
 519		return -EINVAL;
 520	}
 521
 522	if ((!is_power_of_2(src_maxburst) && src_maxburst > 0) ||
 523	    (!is_power_of_2(dst_maxburst) && dst_maxburst > 0)) {
 524		dev_err(chan2dev(chan), "burst size must be a power of 2\n");
 525		return -EINVAL;
 526	}
 527
 528	/*
 529	 * Configure channel control:
 530	 * - Clear SW request as in this case this is a HW one
 531	 * - Clear WEX, HEX and BEX bits
 532	 * - Set priority level
 533	 */
 534	ccr &= ~(STM32_MDMA_CCR_SWRQ | STM32_MDMA_CCR_WEX | STM32_MDMA_CCR_HEX |
 535		 STM32_MDMA_CCR_BEX | STM32_MDMA_CCR_PL_MASK);
 536	ccr |= STM32_MDMA_CCR_PL(chan_config->priority_level);
 537
 538	/* Configure Trigger selection */
 539	ctbr &= ~STM32_MDMA_CTBR_TSEL_MASK;
 540	ctbr |= STM32_MDMA_CTBR_TSEL(chan_config->request);
 541
 542	switch (direction) {
 543	case DMA_MEM_TO_DEV:
 544		dst_addr = chan->dma_config.dst_addr;
 545
 546		/* Set device data size */
 547		if (chan_config->m2m_hw)
 548			dst_addr_width = stm32_mdma_get_max_width(dst_addr, buf_len,
 549								  STM32_MDMA_MAX_BUF_LEN);
 550		dst_bus_width = stm32_mdma_get_width(chan, dst_addr_width);
 551		if (dst_bus_width < 0)
 552			return dst_bus_width;
 553		ctcr &= ~STM32_MDMA_CTCR_DSIZE_MASK;
 554		ctcr |= STM32_MDMA_CTCR_DSIZE(dst_bus_width);
 555		if (chan_config->m2m_hw) {
 556			ctcr &= ~STM32_MDMA_CTCR_DINCOS_MASK;
 557			ctcr |= STM32_MDMA_CTCR_DINCOS(dst_bus_width);
 558		}
 559
 560		/* Set device burst value */
 561		if (chan_config->m2m_hw)
 562			dst_maxburst = STM32_MDMA_MAX_BUF_LEN / dst_addr_width;
 563
 564		dst_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
 565							   dst_maxburst,
 566							   dst_addr_width);
 567		chan->mem_burst = dst_best_burst;
 568		ctcr &= ~STM32_MDMA_CTCR_DBURST_MASK;
 569		ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst)));
 570
 571		/* Set memory data size */
 572		src_addr_width = stm32_mdma_get_max_width(addr, buf_len, tlen);
 573		chan->mem_width = src_addr_width;
 574		src_bus_width = stm32_mdma_get_width(chan, src_addr_width);
 575		if (src_bus_width < 0)
 576			return src_bus_width;
 577		ctcr &= ~STM32_MDMA_CTCR_SSIZE_MASK |
 578			STM32_MDMA_CTCR_SINCOS_MASK;
 579		ctcr |= STM32_MDMA_CTCR_SSIZE(src_bus_width) |
 580			STM32_MDMA_CTCR_SINCOS(src_bus_width);
 581
 582		/* Set memory burst value */
 583		src_maxburst = STM32_MDMA_MAX_BUF_LEN / src_addr_width;
 584		src_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
 585							   src_maxburst,
 586							   src_addr_width);
 587		chan->mem_burst = src_best_burst;
 588		ctcr &= ~STM32_MDMA_CTCR_SBURST_MASK;
 589		ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst)));
 590
 591		/* Select bus */
 592		stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS,
 593				   dst_addr);
 594
 595		if (dst_bus_width != src_bus_width)
 596			ctcr |= STM32_MDMA_CTCR_PKE;
 597
 598		/* Set destination address */
 599		stm32_mdma_write(dmadev, STM32_MDMA_CDAR(chan->id), dst_addr);
 600		break;
 601
 602	case DMA_DEV_TO_MEM:
 603		src_addr = chan->dma_config.src_addr;
 604
 605		/* Set device data size */
 606		if (chan_config->m2m_hw)
 607			src_addr_width = stm32_mdma_get_max_width(src_addr, buf_len,
 608								  STM32_MDMA_MAX_BUF_LEN);
 609
 610		src_bus_width = stm32_mdma_get_width(chan, src_addr_width);
 611		if (src_bus_width < 0)
 612			return src_bus_width;
 613		ctcr &= ~STM32_MDMA_CTCR_SSIZE_MASK;
 614		ctcr |= STM32_MDMA_CTCR_SSIZE(src_bus_width);
 615		if (chan_config->m2m_hw) {
 616			ctcr &= ~STM32_MDMA_CTCR_SINCOS_MASK;
 617			ctcr |= STM32_MDMA_CTCR_SINCOS(src_bus_width);
 618		}
 619
 620		/* Set device burst value */
 621		if (chan_config->m2m_hw)
 622			src_maxburst = STM32_MDMA_MAX_BUF_LEN / src_addr_width;
 623
 624		src_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
 625							   src_maxburst,
 626							   src_addr_width);
 627		ctcr &= ~STM32_MDMA_CTCR_SBURST_MASK;
 628		ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst)));
 629
 630		/* Set memory data size */
 631		dst_addr_width = stm32_mdma_get_max_width(addr, buf_len, tlen);
 632		chan->mem_width = dst_addr_width;
 633		dst_bus_width = stm32_mdma_get_width(chan, dst_addr_width);
 634		if (dst_bus_width < 0)
 635			return dst_bus_width;
 636		ctcr &= ~(STM32_MDMA_CTCR_DSIZE_MASK |
 637			STM32_MDMA_CTCR_DINCOS_MASK);
 638		ctcr |= STM32_MDMA_CTCR_DSIZE(dst_bus_width) |
 639			STM32_MDMA_CTCR_DINCOS(dst_bus_width);
 640
 641		/* Set memory burst value */
 642		dst_maxburst = STM32_MDMA_MAX_BUF_LEN / dst_addr_width;
 643		dst_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
 644							   dst_maxburst,
 645							   dst_addr_width);
 646		ctcr &= ~STM32_MDMA_CTCR_DBURST_MASK;
 647		ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst)));
 648
 649		/* Select bus */
 650		stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS,
 651				   src_addr);
 652
 653		if (dst_bus_width != src_bus_width)
 654			ctcr |= STM32_MDMA_CTCR_PKE;
 655
 656		/* Set source address */
 657		stm32_mdma_write(dmadev, STM32_MDMA_CSAR(chan->id), src_addr);
 658		break;
 659
 660	default:
 661		dev_err(chan2dev(chan), "Dma direction is not supported\n");
 662		return -EINVAL;
 663	}
 664
 665	*mdma_ccr = ccr;
 666	*mdma_ctcr = ctcr;
 667	*mdma_ctbr = ctbr;
 668
 669	return 0;
 670}
 671
 672static void stm32_mdma_dump_hwdesc(struct stm32_mdma_chan *chan,
 673				   struct stm32_mdma_desc_node *node)
 674{
 675	dev_dbg(chan2dev(chan), "hwdesc:  %pad\n", &node->hwdesc_phys);
 676	dev_dbg(chan2dev(chan), "CTCR:    0x%08x\n", node->hwdesc->ctcr);
 677	dev_dbg(chan2dev(chan), "CBNDTR:  0x%08x\n", node->hwdesc->cbndtr);
 678	dev_dbg(chan2dev(chan), "CSAR:    0x%08x\n", node->hwdesc->csar);
 679	dev_dbg(chan2dev(chan), "CDAR:    0x%08x\n", node->hwdesc->cdar);
 680	dev_dbg(chan2dev(chan), "CBRUR:   0x%08x\n", node->hwdesc->cbrur);
 681	dev_dbg(chan2dev(chan), "CLAR:    0x%08x\n", node->hwdesc->clar);
 682	dev_dbg(chan2dev(chan), "CTBR:    0x%08x\n", node->hwdesc->ctbr);
 683	dev_dbg(chan2dev(chan), "CMAR:    0x%08x\n", node->hwdesc->cmar);
 684	dev_dbg(chan2dev(chan), "CMDR:    0x%08x\n\n", node->hwdesc->cmdr);
 685}
 686
 687static void stm32_mdma_setup_hwdesc(struct stm32_mdma_chan *chan,
 688				    struct stm32_mdma_desc *desc,
 689				    enum dma_transfer_direction dir, u32 count,
 690				    dma_addr_t src_addr, dma_addr_t dst_addr,
 691				    u32 len, u32 ctcr, u32 ctbr, bool is_last,
 692				    bool is_first, bool is_cyclic)
 693{
 694	struct stm32_mdma_chan_config *config = &chan->chan_config;
 695	struct stm32_mdma_hwdesc *hwdesc;
 696	u32 next = count + 1;
 697
 698	hwdesc = desc->node[count].hwdesc;
 699	hwdesc->ctcr = ctcr;
 700	hwdesc->cbndtr &= ~(STM32_MDMA_CBNDTR_BRC_MK |
 701			STM32_MDMA_CBNDTR_BRDUM |
 702			STM32_MDMA_CBNDTR_BRSUM |
 703			STM32_MDMA_CBNDTR_BNDT_MASK);
 704	hwdesc->cbndtr |= STM32_MDMA_CBNDTR_BNDT(len);
 705	hwdesc->csar = src_addr;
 706	hwdesc->cdar = dst_addr;
 707	hwdesc->cbrur = 0;
 708	hwdesc->ctbr = ctbr;
 709	hwdesc->cmar = config->mask_addr;
 710	hwdesc->cmdr = config->mask_data;
 711
 712	if (is_last) {
 713		if (is_cyclic)
 714			hwdesc->clar = desc->node[0].hwdesc_phys;
 715		else
 716			hwdesc->clar = 0;
 717	} else {
 718		hwdesc->clar = desc->node[next].hwdesc_phys;
 719	}
 720
 721	stm32_mdma_dump_hwdesc(chan, &desc->node[count]);
 722}
 723
 724static int stm32_mdma_setup_xfer(struct stm32_mdma_chan *chan,
 725				 struct stm32_mdma_desc *desc,
 726				 struct scatterlist *sgl, u32 sg_len,
 727				 enum dma_transfer_direction direction)
 728{
 729	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
 730	struct dma_slave_config *dma_config = &chan->dma_config;
 731	struct stm32_mdma_chan_config *chan_config = &chan->chan_config;
 732	struct scatterlist *sg;
 733	dma_addr_t src_addr, dst_addr;
 734	u32 m2m_hw_period, ccr, ctcr, ctbr;
 735	int i, ret = 0;
 736
 737	if (chan_config->m2m_hw)
 738		m2m_hw_period = sg_dma_len(sgl);
 739
 740	for_each_sg(sgl, sg, sg_len, i) {
 741		if (sg_dma_len(sg) > STM32_MDMA_MAX_BLOCK_LEN) {
 742			dev_err(chan2dev(chan), "Invalid block len\n");
 743			return -EINVAL;
 744		}
 745
 746		if (direction == DMA_MEM_TO_DEV) {
 747			src_addr = sg_dma_address(sg);
 748			dst_addr = dma_config->dst_addr;
 749			if (chan_config->m2m_hw && (i & 1))
 750				dst_addr += m2m_hw_period;
 751			ret = stm32_mdma_set_xfer_param(chan, direction, &ccr,
 752							&ctcr, &ctbr, src_addr,
 753							sg_dma_len(sg));
 754			stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS,
 755					   src_addr);
 756		} else {
 757			src_addr = dma_config->src_addr;
 758			if (chan_config->m2m_hw && (i & 1))
 759				src_addr += m2m_hw_period;
 760			dst_addr = sg_dma_address(sg);
 761			ret = stm32_mdma_set_xfer_param(chan, direction, &ccr,
 762							&ctcr, &ctbr, dst_addr,
 763							sg_dma_len(sg));
 764			stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS,
 765					   dst_addr);
 766		}
 767
 768		if (ret < 0)
 769			return ret;
 770
 771		stm32_mdma_setup_hwdesc(chan, desc, direction, i, src_addr,
 772					dst_addr, sg_dma_len(sg), ctcr, ctbr,
 773					i == sg_len - 1, i == 0, false);
 774	}
 775
 776	/* Enable interrupts */
 777	ccr &= ~STM32_MDMA_CCR_IRQ_MASK;
 778	ccr |= STM32_MDMA_CCR_TEIE | STM32_MDMA_CCR_CTCIE;
 779	desc->ccr = ccr;
 780
 781	return 0;
 782}
 783
 784static struct dma_async_tx_descriptor *
 785stm32_mdma_prep_slave_sg(struct dma_chan *c, struct scatterlist *sgl,
 786			 u32 sg_len, enum dma_transfer_direction direction,
 787			 unsigned long flags, void *context)
 788{
 789	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
 790	struct stm32_mdma_chan_config *chan_config = &chan->chan_config;
 791	struct stm32_mdma_desc *desc;
 792	int i, ret;
 793
 794	/*
 795	 * Once DMA is in setup cyclic mode the channel we cannot assign this
 796	 * channel anymore. The DMA channel needs to be aborted or terminated
 797	 * for allowing another request.
 798	 */
 799	if (chan->desc && chan->desc->cyclic) {
 800		dev_err(chan2dev(chan),
 801			"Request not allowed when dma in cyclic mode\n");
 802		return NULL;
 803	}
 804
 805	desc = stm32_mdma_alloc_desc(chan, sg_len);
 806	if (!desc)
 807		return NULL;
 808
 809	ret = stm32_mdma_setup_xfer(chan, desc, sgl, sg_len, direction);
 810	if (ret < 0)
 811		goto xfer_setup_err;
 812
 813	/*
 814	 * In case of M2M HW transfer triggered by STM32 DMA, we do not have to clear the
 815	 * transfer complete flag by hardware in order to let the CPU rearm the STM32 DMA
 816	 * with the next sg element and update some data in dmaengine framework.
 817	 */
 818	if (chan_config->m2m_hw && direction == DMA_MEM_TO_DEV) {
 819		struct stm32_mdma_hwdesc *hwdesc;
 820
 821		for (i = 0; i < sg_len; i++) {
 822			hwdesc = desc->node[i].hwdesc;
 823			hwdesc->cmar = 0;
 824			hwdesc->cmdr = 0;
 825		}
 826	}
 827
 828	desc->cyclic = false;
 829
 830	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
 831
 832xfer_setup_err:
 833	for (i = 0; i < desc->count; i++)
 834		dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
 835			      desc->node[i].hwdesc_phys);
 836	kfree(desc);
 837	return NULL;
 838}
 839
 840static struct dma_async_tx_descriptor *
 841stm32_mdma_prep_dma_cyclic(struct dma_chan *c, dma_addr_t buf_addr,
 842			   size_t buf_len, size_t period_len,
 843			   enum dma_transfer_direction direction,
 844			   unsigned long flags)
 845{
 846	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
 847	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
 848	struct dma_slave_config *dma_config = &chan->dma_config;
 849	struct stm32_mdma_chan_config *chan_config = &chan->chan_config;
 850	struct stm32_mdma_desc *desc;
 851	dma_addr_t src_addr, dst_addr;
 852	u32 ccr, ctcr, ctbr, count;
 853	int i, ret;
 854
 855	/*
 856	 * Once DMA is in setup cyclic mode the channel we cannot assign this
 857	 * channel anymore. The DMA channel needs to be aborted or terminated
 858	 * for allowing another request.
 859	 */
 860	if (chan->desc && chan->desc->cyclic) {
 861		dev_err(chan2dev(chan),
 862			"Request not allowed when dma in cyclic mode\n");
 863		return NULL;
 864	}
 865
 866	if (!buf_len || !period_len || period_len > STM32_MDMA_MAX_BLOCK_LEN) {
 867		dev_err(chan2dev(chan), "Invalid buffer/period len\n");
 868		return NULL;
 869	}
 870
 871	if (buf_len % period_len) {
 872		dev_err(chan2dev(chan), "buf_len not multiple of period_len\n");
 873		return NULL;
 874	}
 875
 876	count = buf_len / period_len;
 877
 878	desc = stm32_mdma_alloc_desc(chan, count);
 879	if (!desc)
 880		return NULL;
 881
 882	/* Select bus */
 883	if (direction == DMA_MEM_TO_DEV) {
 884		src_addr = buf_addr;
 885		ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr,
 886						&ctbr, src_addr, period_len);
 887		stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS,
 888				   src_addr);
 889	} else {
 890		dst_addr = buf_addr;
 891		ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr,
 892						&ctbr, dst_addr, period_len);
 893		stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS,
 894				   dst_addr);
 895	}
 896
 897	if (ret < 0)
 898		goto xfer_setup_err;
 899
 900	/* Enable interrupts */
 901	ccr &= ~STM32_MDMA_CCR_IRQ_MASK;
 902	ccr |= STM32_MDMA_CCR_TEIE | STM32_MDMA_CCR_CTCIE | STM32_MDMA_CCR_BTIE;
 903	desc->ccr = ccr;
 904
 905	/* Configure hwdesc list */
 906	for (i = 0; i < count; i++) {
 907		if (direction == DMA_MEM_TO_DEV) {
 908			src_addr = buf_addr + i * period_len;
 909			dst_addr = dma_config->dst_addr;
 910			if (chan_config->m2m_hw && (i & 1))
 911				dst_addr += period_len;
 912		} else {
 913			src_addr = dma_config->src_addr;
 914			if (chan_config->m2m_hw && (i & 1))
 915				src_addr += period_len;
 916			dst_addr = buf_addr + i * period_len;
 917		}
 918
 919		stm32_mdma_setup_hwdesc(chan, desc, direction, i, src_addr,
 920					dst_addr, period_len, ctcr, ctbr,
 921					i == count - 1, i == 0, true);
 922	}
 923
 924	desc->cyclic = true;
 925
 926	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
 927
 928xfer_setup_err:
 929	for (i = 0; i < desc->count; i++)
 930		dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
 931			      desc->node[i].hwdesc_phys);
 932	kfree(desc);
 933	return NULL;
 934}
 935
 936static struct dma_async_tx_descriptor *
 937stm32_mdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest, dma_addr_t src,
 938			   size_t len, unsigned long flags)
 939{
 940	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
 941	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
 942	enum dma_slave_buswidth max_width;
 943	struct stm32_mdma_desc *desc;
 944	struct stm32_mdma_hwdesc *hwdesc;
 945	u32 ccr, ctcr, ctbr, cbndtr, count, max_burst, mdma_burst;
 946	u32 best_burst, tlen;
 947	size_t xfer_count, offset;
 948	int src_bus_width, dst_bus_width;
 949	int i;
 950
 951	/*
 952	 * Once DMA is in setup cyclic mode the channel we cannot assign this
 953	 * channel anymore. The DMA channel needs to be aborted or terminated
 954	 * to allow another request
 955	 */
 956	if (chan->desc && chan->desc->cyclic) {
 957		dev_err(chan2dev(chan),
 958			"Request not allowed when dma in cyclic mode\n");
 959		return NULL;
 960	}
 961
 962	count = DIV_ROUND_UP(len, STM32_MDMA_MAX_BLOCK_LEN);
 963	desc = stm32_mdma_alloc_desc(chan, count);
 964	if (!desc)
 965		return NULL;
 966
 967	ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)) & ~STM32_MDMA_CCR_EN;
 968	ctcr = stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id));
 969	ctbr = stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id));
 970	cbndtr = stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id));
 971
 972	/* Enable sw req, some interrupts and clear other bits */
 973	ccr &= ~(STM32_MDMA_CCR_WEX | STM32_MDMA_CCR_HEX |
 974		 STM32_MDMA_CCR_BEX | STM32_MDMA_CCR_PL_MASK |
 975		 STM32_MDMA_CCR_IRQ_MASK);
 976	ccr |= STM32_MDMA_CCR_TEIE;
 977
 978	/* Enable SW request mode, dest/src inc and clear other bits */
 979	ctcr &= ~(STM32_MDMA_CTCR_BWM | STM32_MDMA_CTCR_TRGM_MSK |
 980		  STM32_MDMA_CTCR_PAM_MASK | STM32_MDMA_CTCR_PKE |
 981		  STM32_MDMA_CTCR_TLEN_MSK | STM32_MDMA_CTCR_DBURST_MASK |
 982		  STM32_MDMA_CTCR_SBURST_MASK | STM32_MDMA_CTCR_DINCOS_MASK |
 983		  STM32_MDMA_CTCR_SINCOS_MASK | STM32_MDMA_CTCR_DSIZE_MASK |
 984		  STM32_MDMA_CTCR_SSIZE_MASK | STM32_MDMA_CTCR_DINC_MASK |
 985		  STM32_MDMA_CTCR_SINC_MASK);
 986	ctcr |= STM32_MDMA_CTCR_SWRM | STM32_MDMA_CTCR_SINC(STM32_MDMA_INC) |
 987		STM32_MDMA_CTCR_DINC(STM32_MDMA_INC);
 988
 989	/* Reset HW request */
 990	ctbr &= ~STM32_MDMA_CTBR_TSEL_MASK;
 991
 992	/* Select bus */
 993	stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS, src);
 994	stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS, dest);
 995
 996	/* Clear CBNDTR registers */
 997	cbndtr &= ~(STM32_MDMA_CBNDTR_BRC_MK | STM32_MDMA_CBNDTR_BRDUM |
 998			STM32_MDMA_CBNDTR_BRSUM | STM32_MDMA_CBNDTR_BNDT_MASK);
 999
1000	if (len <= STM32_MDMA_MAX_BLOCK_LEN) {
1001		cbndtr |= STM32_MDMA_CBNDTR_BNDT(len);
1002		if (len <= STM32_MDMA_MAX_BUF_LEN) {
1003			/* Setup a buffer transfer */
1004			ccr |= STM32_MDMA_CCR_TCIE | STM32_MDMA_CCR_CTCIE;
1005			ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BUFFER);
1006		} else {
1007			/* Setup a block transfer */
1008			ccr |= STM32_MDMA_CCR_BTIE | STM32_MDMA_CCR_CTCIE;
1009			ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BLOCK);
1010		}
1011
1012		tlen = STM32_MDMA_MAX_BUF_LEN;
1013		ctcr |= STM32_MDMA_CTCR_TLEN((tlen - 1));
1014
1015		/* Set source best burst size */
1016		max_width = stm32_mdma_get_max_width(src, len, tlen);
1017		src_bus_width = stm32_mdma_get_width(chan, max_width);
1018
1019		max_burst = tlen / max_width;
1020		best_burst = stm32_mdma_get_best_burst(len, tlen, max_burst,
1021						       max_width);
1022		mdma_burst = ilog2(best_burst);
1023
1024		ctcr |= STM32_MDMA_CTCR_SBURST(mdma_burst) |
1025			STM32_MDMA_CTCR_SSIZE(src_bus_width) |
1026			STM32_MDMA_CTCR_SINCOS(src_bus_width);
1027
1028		/* Set destination best burst size */
1029		max_width = stm32_mdma_get_max_width(dest, len, tlen);
1030		dst_bus_width = stm32_mdma_get_width(chan, max_width);
1031
1032		max_burst = tlen / max_width;
1033		best_burst = stm32_mdma_get_best_burst(len, tlen, max_burst,
1034						       max_width);
1035		mdma_burst = ilog2(best_burst);
1036
1037		ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) |
1038			STM32_MDMA_CTCR_DSIZE(dst_bus_width) |
1039			STM32_MDMA_CTCR_DINCOS(dst_bus_width);
1040
1041		if (dst_bus_width != src_bus_width)
1042			ctcr |= STM32_MDMA_CTCR_PKE;
1043
1044		/* Prepare hardware descriptor */
1045		hwdesc = desc->node[0].hwdesc;
1046		hwdesc->ctcr = ctcr;
1047		hwdesc->cbndtr = cbndtr;
1048		hwdesc->csar = src;
1049		hwdesc->cdar = dest;
1050		hwdesc->cbrur = 0;
1051		hwdesc->clar = 0;
1052		hwdesc->ctbr = ctbr;
1053		hwdesc->cmar = 0;
1054		hwdesc->cmdr = 0;
1055
1056		stm32_mdma_dump_hwdesc(chan, &desc->node[0]);
1057	} else {
1058		/* Setup a LLI transfer */
1059		ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_LINKED_LIST) |
1060			STM32_MDMA_CTCR_TLEN((STM32_MDMA_MAX_BUF_LEN - 1));
1061		ccr |= STM32_MDMA_CCR_BTIE | STM32_MDMA_CCR_CTCIE;
1062		tlen = STM32_MDMA_MAX_BUF_LEN;
1063
1064		for (i = 0, offset = 0; offset < len;
1065		     i++, offset += xfer_count) {
1066			xfer_count = min_t(size_t, len - offset,
1067					   STM32_MDMA_MAX_BLOCK_LEN);
1068
1069			/* Set source best burst size */
1070			max_width = stm32_mdma_get_max_width(src, len, tlen);
1071			src_bus_width = stm32_mdma_get_width(chan, max_width);
1072
1073			max_burst = tlen / max_width;
1074			best_burst = stm32_mdma_get_best_burst(len, tlen,
1075							       max_burst,
1076							       max_width);
1077			mdma_burst = ilog2(best_burst);
1078
1079			ctcr |= STM32_MDMA_CTCR_SBURST(mdma_burst) |
1080				STM32_MDMA_CTCR_SSIZE(src_bus_width) |
1081				STM32_MDMA_CTCR_SINCOS(src_bus_width);
1082
1083			/* Set destination best burst size */
1084			max_width = stm32_mdma_get_max_width(dest, len, tlen);
1085			dst_bus_width = stm32_mdma_get_width(chan, max_width);
1086
1087			max_burst = tlen / max_width;
1088			best_burst = stm32_mdma_get_best_burst(len, tlen,
1089							       max_burst,
1090							       max_width);
1091			mdma_burst = ilog2(best_burst);
1092
1093			ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) |
1094				STM32_MDMA_CTCR_DSIZE(dst_bus_width) |
1095				STM32_MDMA_CTCR_DINCOS(dst_bus_width);
1096
1097			if (dst_bus_width != src_bus_width)
1098				ctcr |= STM32_MDMA_CTCR_PKE;
1099
1100			/* Prepare hardware descriptor */
1101			stm32_mdma_setup_hwdesc(chan, desc, DMA_MEM_TO_MEM, i,
1102						src + offset, dest + offset,
1103						xfer_count, ctcr, ctbr,
1104						i == count - 1, i == 0, false);
1105		}
1106	}
1107
1108	desc->ccr = ccr;
1109
1110	desc->cyclic = false;
1111
1112	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
1113}
1114
1115static void stm32_mdma_dump_reg(struct stm32_mdma_chan *chan)
1116{
1117	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
1118
1119	dev_dbg(chan2dev(chan), "CCR:     0x%08x\n",
1120		stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)));
1121	dev_dbg(chan2dev(chan), "CTCR:    0x%08x\n",
1122		stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id)));
1123	dev_dbg(chan2dev(chan), "CBNDTR:  0x%08x\n",
1124		stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id)));
1125	dev_dbg(chan2dev(chan), "CSAR:    0x%08x\n",
1126		stm32_mdma_read(dmadev, STM32_MDMA_CSAR(chan->id)));
1127	dev_dbg(chan2dev(chan), "CDAR:    0x%08x\n",
1128		stm32_mdma_read(dmadev, STM32_MDMA_CDAR(chan->id)));
1129	dev_dbg(chan2dev(chan), "CBRUR:   0x%08x\n",
1130		stm32_mdma_read(dmadev, STM32_MDMA_CBRUR(chan->id)));
1131	dev_dbg(chan2dev(chan), "CLAR:    0x%08x\n",
1132		stm32_mdma_read(dmadev, STM32_MDMA_CLAR(chan->id)));
1133	dev_dbg(chan2dev(chan), "CTBR:    0x%08x\n",
1134		stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id)));
1135	dev_dbg(chan2dev(chan), "CMAR:    0x%08x\n",
1136		stm32_mdma_read(dmadev, STM32_MDMA_CMAR(chan->id)));
1137	dev_dbg(chan2dev(chan), "CMDR:    0x%08x\n",
1138		stm32_mdma_read(dmadev, STM32_MDMA_CMDR(chan->id)));
1139}
1140
1141static void stm32_mdma_start_transfer(struct stm32_mdma_chan *chan)
1142{
1143	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
1144	struct virt_dma_desc *vdesc;
1145	struct stm32_mdma_hwdesc *hwdesc;
1146	u32 id = chan->id;
1147	u32 status, reg;
1148
1149	vdesc = vchan_next_desc(&chan->vchan);
1150	if (!vdesc) {
1151		chan->desc = NULL;
1152		return;
1153	}
1154
1155	list_del(&vdesc->node);
1156
1157	chan->desc = to_stm32_mdma_desc(vdesc);
1158	hwdesc = chan->desc->node[0].hwdesc;
1159	chan->curr_hwdesc = 0;
1160
1161	stm32_mdma_write(dmadev, STM32_MDMA_CCR(id), chan->desc->ccr);
1162	stm32_mdma_write(dmadev, STM32_MDMA_CTCR(id), hwdesc->ctcr);
1163	stm32_mdma_write(dmadev, STM32_MDMA_CBNDTR(id), hwdesc->cbndtr);
1164	stm32_mdma_write(dmadev, STM32_MDMA_CSAR(id), hwdesc->csar);
1165	stm32_mdma_write(dmadev, STM32_MDMA_CDAR(id), hwdesc->cdar);
1166	stm32_mdma_write(dmadev, STM32_MDMA_CBRUR(id), hwdesc->cbrur);
1167	stm32_mdma_write(dmadev, STM32_MDMA_CLAR(id), hwdesc->clar);
1168	stm32_mdma_write(dmadev, STM32_MDMA_CTBR(id), hwdesc->ctbr);
1169	stm32_mdma_write(dmadev, STM32_MDMA_CMAR(id), hwdesc->cmar);
1170	stm32_mdma_write(dmadev, STM32_MDMA_CMDR(id), hwdesc->cmdr);
1171
1172	/* Clear interrupt status if it is there */
1173	status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(id));
1174	if (status)
1175		stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(id), status);
1176
1177	stm32_mdma_dump_reg(chan);
1178
1179	/* Start DMA */
1180	stm32_mdma_set_bits(dmadev, STM32_MDMA_CCR(id), STM32_MDMA_CCR_EN);
1181
1182	/* Set SW request in case of MEM2MEM transfer */
1183	if (hwdesc->ctcr & STM32_MDMA_CTCR_SWRM) {
1184		reg = STM32_MDMA_CCR(id);
1185		stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_SWRQ);
1186	}
1187
1188	chan->busy = true;
1189
1190	dev_dbg(chan2dev(chan), "vchan %pK: started\n", &chan->vchan);
1191}
1192
1193static void stm32_mdma_issue_pending(struct dma_chan *c)
1194{
1195	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1196	unsigned long flags;
1197
1198	spin_lock_irqsave(&chan->vchan.lock, flags);
1199
1200	if (!vchan_issue_pending(&chan->vchan))
1201		goto end;
1202
1203	dev_dbg(chan2dev(chan), "vchan %pK: issued\n", &chan->vchan);
1204
1205	if (!chan->desc && !chan->busy)
1206		stm32_mdma_start_transfer(chan);
1207
1208end:
1209	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1210}
1211
1212static int stm32_mdma_pause(struct dma_chan *c)
1213{
1214	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1215	unsigned long flags;
1216	int ret;
1217
1218	spin_lock_irqsave(&chan->vchan.lock, flags);
1219	ret = stm32_mdma_disable_chan(chan);
1220	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1221
1222	if (!ret)
1223		dev_dbg(chan2dev(chan), "vchan %pK: pause\n", &chan->vchan);
1224
1225	return ret;
1226}
1227
1228static int stm32_mdma_resume(struct dma_chan *c)
1229{
1230	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1231	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
1232	struct stm32_mdma_hwdesc *hwdesc;
1233	unsigned long flags;
1234	u32 status, reg;
1235
1236	/* Transfer can be terminated */
1237	if (!chan->desc || (stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)) & STM32_MDMA_CCR_EN))
1238		return -EPERM;
1239
1240	hwdesc = chan->desc->node[chan->curr_hwdesc].hwdesc;
1241
1242	spin_lock_irqsave(&chan->vchan.lock, flags);
1243
1244	/* Re-configure control register */
1245	stm32_mdma_write(dmadev, STM32_MDMA_CCR(chan->id), chan->desc->ccr);
1246
1247	/* Clear interrupt status if it is there */
1248	status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id));
1249	if (status)
1250		stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(chan->id), status);
1251
1252	stm32_mdma_dump_reg(chan);
1253
1254	/* Re-start DMA */
1255	reg = STM32_MDMA_CCR(chan->id);
1256	stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_EN);
1257
1258	/* Set SW request in case of MEM2MEM transfer */
1259	if (hwdesc->ctcr & STM32_MDMA_CTCR_SWRM)
1260		stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_SWRQ);
1261
1262	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1263
1264	dev_dbg(chan2dev(chan), "vchan %pK: resume\n", &chan->vchan);
1265
1266	return 0;
1267}
1268
1269static int stm32_mdma_terminate_all(struct dma_chan *c)
1270{
1271	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1272	unsigned long flags;
1273	LIST_HEAD(head);
1274
1275	spin_lock_irqsave(&chan->vchan.lock, flags);
1276	if (chan->desc) {
1277		vchan_terminate_vdesc(&chan->desc->vdesc);
1278		if (chan->busy)
1279			stm32_mdma_stop(chan);
1280		chan->desc = NULL;
1281	}
1282	vchan_get_all_descriptors(&chan->vchan, &head);
1283	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1284
1285	vchan_dma_desc_free_list(&chan->vchan, &head);
1286
1287	return 0;
1288}
1289
1290static void stm32_mdma_synchronize(struct dma_chan *c)
1291{
1292	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1293
1294	vchan_synchronize(&chan->vchan);
1295}
1296
1297static int stm32_mdma_slave_config(struct dma_chan *c,
1298				   struct dma_slave_config *config)
1299{
1300	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1301
1302	memcpy(&chan->dma_config, config, sizeof(*config));
1303
1304	/* Check if user is requesting STM32 DMA to trigger MDMA */
1305	if (config->peripheral_size) {
1306		struct stm32_mdma_dma_config *mdma_config;
1307
1308		mdma_config = (struct stm32_mdma_dma_config *)chan->dma_config.peripheral_config;
1309		chan->chan_config.request = mdma_config->request;
1310		chan->chan_config.mask_addr = mdma_config->cmar;
1311		chan->chan_config.mask_data = mdma_config->cmdr;
1312		chan->chan_config.m2m_hw = true;
1313	}
1314
1315	return 0;
1316}
1317
1318static size_t stm32_mdma_desc_residue(struct stm32_mdma_chan *chan,
1319				      struct stm32_mdma_desc *desc,
1320				      u32 curr_hwdesc,
1321				      struct dma_tx_state *state)
1322{
1323	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
1324	struct stm32_mdma_hwdesc *hwdesc;
1325	u32 cisr, clar, cbndtr, residue, modulo, burst_size;
1326	int i;
1327
1328	cisr = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id));
1329
1330	residue = 0;
1331	/* Get the next hw descriptor to process from current transfer */
1332	clar = stm32_mdma_read(dmadev, STM32_MDMA_CLAR(chan->id));
1333	for (i = desc->count - 1; i >= 0; i--) {
1334		hwdesc = desc->node[i].hwdesc;
1335
1336		if (hwdesc->clar == clar)
1337			break;/* Current transfer found, stop cumulating */
1338
1339		/* Cumulate residue of unprocessed hw descriptors */
1340		residue += STM32_MDMA_CBNDTR_BNDT(hwdesc->cbndtr);
1341	}
1342	cbndtr = stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id));
1343	residue += cbndtr & STM32_MDMA_CBNDTR_BNDT_MASK;
1344
1345	state->in_flight_bytes = 0;
1346	if (chan->chan_config.m2m_hw && (cisr & STM32_MDMA_CISR_CRQA))
1347		state->in_flight_bytes = cbndtr & STM32_MDMA_CBNDTR_BNDT_MASK;
1348
1349	if (!chan->mem_burst)
1350		return residue;
1351
1352	burst_size = chan->mem_burst * chan->mem_width;
1353	modulo = residue % burst_size;
1354	if (modulo)
1355		residue = residue - modulo + burst_size;
1356
1357	return residue;
1358}
1359
1360static enum dma_status stm32_mdma_tx_status(struct dma_chan *c,
1361					    dma_cookie_t cookie,
1362					    struct dma_tx_state *state)
1363{
1364	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1365	struct virt_dma_desc *vdesc;
1366	enum dma_status status;
1367	unsigned long flags;
1368	u32 residue = 0;
1369
1370	status = dma_cookie_status(c, cookie, state);
1371	if ((status == DMA_COMPLETE) || (!state))
1372		return status;
1373
1374	spin_lock_irqsave(&chan->vchan.lock, flags);
1375
1376	vdesc = vchan_find_desc(&chan->vchan, cookie);
1377	if (chan->desc && cookie == chan->desc->vdesc.tx.cookie)
1378		residue = stm32_mdma_desc_residue(chan, chan->desc, chan->curr_hwdesc, state);
1379	else if (vdesc)
1380		residue = stm32_mdma_desc_residue(chan, to_stm32_mdma_desc(vdesc), 0, state);
1381
1382	dma_set_residue(state, residue);
1383
1384	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1385
1386	return status;
1387}
1388
1389static void stm32_mdma_xfer_end(struct stm32_mdma_chan *chan)
1390{
1391	vchan_cookie_complete(&chan->desc->vdesc);
1392	chan->desc = NULL;
1393	chan->busy = false;
1394
1395	/* Start the next transfer if this driver has a next desc */
1396	stm32_mdma_start_transfer(chan);
1397}
1398
1399static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid)
1400{
1401	struct stm32_mdma_device *dmadev = devid;
1402	struct stm32_mdma_chan *chan;
1403	u32 reg, id, ccr, ien, status;
1404
1405	/* Find out which channel generates the interrupt */
1406	status = readl_relaxed(dmadev->base + STM32_MDMA_GISR0);
1407	if (!status) {
1408		dev_dbg(mdma2dev(dmadev), "spurious it\n");
1409		return IRQ_NONE;
1410	}
1411	id = __ffs(status);
1412	chan = &dmadev->chan[id];
1413
1414	/* Handle interrupt for the channel */
1415	spin_lock(&chan->vchan.lock);
1416	status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(id));
1417	/* Mask Channel ReQuest Active bit which can be set in case of MEM2MEM */
1418	status &= ~STM32_MDMA_CISR_CRQA;
1419	ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(id));
1420	ien = (ccr & STM32_MDMA_CCR_IRQ_MASK) >> 1;
1421
1422	if (!(status & ien)) {
1423		spin_unlock(&chan->vchan.lock);
1424		if (chan->busy)
1425			dev_warn(chan2dev(chan),
1426				 "spurious it (status=0x%04x, ien=0x%04x)\n", status, ien);
1427		else
1428			dev_dbg(chan2dev(chan),
1429				"spurious it (status=0x%04x, ien=0x%04x)\n", status, ien);
1430		return IRQ_NONE;
1431	}
1432
1433	reg = STM32_MDMA_CIFCR(id);
1434
1435	if (status & STM32_MDMA_CISR_TEIF) {
1436		dev_err(chan2dev(chan), "Transfer Err: stat=0x%08x\n",
1437			readl_relaxed(dmadev->base + STM32_MDMA_CESR(id)));
1438		stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CTEIF);
1439		status &= ~STM32_MDMA_CISR_TEIF;
1440	}
1441
1442	if (status & STM32_MDMA_CISR_CTCIF) {
1443		stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CCTCIF);
1444		status &= ~STM32_MDMA_CISR_CTCIF;
1445		stm32_mdma_xfer_end(chan);
1446	}
1447
1448	if (status & STM32_MDMA_CISR_BRTIF) {
1449		stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBRTIF);
1450		status &= ~STM32_MDMA_CISR_BRTIF;
1451	}
1452
1453	if (status & STM32_MDMA_CISR_BTIF) {
1454		stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBTIF);
1455		status &= ~STM32_MDMA_CISR_BTIF;
1456		chan->curr_hwdesc++;
1457		if (chan->desc && chan->desc->cyclic) {
1458			if (chan->curr_hwdesc == chan->desc->count)
1459				chan->curr_hwdesc = 0;
1460			vchan_cyclic_callback(&chan->desc->vdesc);
1461		}
1462	}
1463
1464	if (status & STM32_MDMA_CISR_TCIF) {
1465		stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CLTCIF);
1466		status &= ~STM32_MDMA_CISR_TCIF;
1467	}
1468
1469	if (status) {
1470		stm32_mdma_set_bits(dmadev, reg, status);
1471		dev_err(chan2dev(chan), "DMA error: status=0x%08x\n", status);
1472		if (!(ccr & STM32_MDMA_CCR_EN))
1473			dev_err(chan2dev(chan), "chan disabled by HW\n");
1474	}
1475
1476	spin_unlock(&chan->vchan.lock);
1477
1478	return IRQ_HANDLED;
1479}
1480
1481static int stm32_mdma_alloc_chan_resources(struct dma_chan *c)
1482{
1483	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1484	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
1485	int ret;
1486
1487	chan->desc_pool = dmam_pool_create(dev_name(&c->dev->device),
1488					   c->device->dev,
1489					   sizeof(struct stm32_mdma_hwdesc),
1490					  __alignof__(struct stm32_mdma_hwdesc),
1491					   0);
1492	if (!chan->desc_pool) {
1493		dev_err(chan2dev(chan), "failed to allocate descriptor pool\n");
1494		return -ENOMEM;
1495	}
1496
1497	ret = pm_runtime_resume_and_get(dmadev->ddev.dev);
1498	if (ret < 0)
1499		return ret;
1500
1501	ret = stm32_mdma_disable_chan(chan);
1502	if (ret < 0)
1503		pm_runtime_put(dmadev->ddev.dev);
1504
1505	return ret;
1506}
1507
1508static void stm32_mdma_free_chan_resources(struct dma_chan *c)
1509{
1510	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1511	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
1512	unsigned long flags;
1513
1514	dev_dbg(chan2dev(chan), "Freeing channel %d\n", chan->id);
1515
1516	if (chan->busy) {
1517		spin_lock_irqsave(&chan->vchan.lock, flags);
1518		stm32_mdma_stop(chan);
1519		chan->desc = NULL;
1520		spin_unlock_irqrestore(&chan->vchan.lock, flags);
1521	}
1522
1523	pm_runtime_put(dmadev->ddev.dev);
1524	vchan_free_chan_resources(to_virt_chan(c));
1525	dmam_pool_destroy(chan->desc_pool);
1526	chan->desc_pool = NULL;
1527}
1528
1529static bool stm32_mdma_filter_fn(struct dma_chan *c, void *fn_param)
1530{
1531	struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
1532	struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
1533
1534	/* Check if chan is marked Secure */
1535	if (dmadev->chan_reserved & BIT(chan->id))
1536		return false;
1537
1538	return true;
1539}
1540
1541static struct dma_chan *stm32_mdma_of_xlate(struct of_phandle_args *dma_spec,
1542					    struct of_dma *ofdma)
1543{
1544	struct stm32_mdma_device *dmadev = ofdma->of_dma_data;
1545	dma_cap_mask_t mask = dmadev->ddev.cap_mask;
1546	struct stm32_mdma_chan *chan;
1547	struct dma_chan *c;
1548	struct stm32_mdma_chan_config config;
1549
1550	if (dma_spec->args_count < 5) {
1551		dev_err(mdma2dev(dmadev), "Bad number of args\n");
1552		return NULL;
1553	}
1554
1555	memset(&config, 0, sizeof(config));
1556	config.request = dma_spec->args[0];
1557	config.priority_level = dma_spec->args[1];
1558	config.transfer_config = dma_spec->args[2];
1559	config.mask_addr = dma_spec->args[3];
1560	config.mask_data = dma_spec->args[4];
1561
1562	if (config.request >= dmadev->nr_requests) {
1563		dev_err(mdma2dev(dmadev), "Bad request line\n");
1564		return NULL;
1565	}
1566
1567	if (config.priority_level > STM32_MDMA_VERY_HIGH_PRIORITY) {
1568		dev_err(mdma2dev(dmadev), "Priority level not supported\n");
1569		return NULL;
1570	}
1571
1572	c = __dma_request_channel(&mask, stm32_mdma_filter_fn, &config, ofdma->of_node);
1573	if (!c) {
1574		dev_err(mdma2dev(dmadev), "No more channels available\n");
1575		return NULL;
1576	}
1577
1578	chan = to_stm32_mdma_chan(c);
1579	chan->chan_config = config;
1580
1581	return c;
1582}
1583
1584static const struct of_device_id stm32_mdma_of_match[] = {
1585	{ .compatible = "st,stm32h7-mdma", },
1586	{ /* sentinel */ },
1587};
1588MODULE_DEVICE_TABLE(of, stm32_mdma_of_match);
1589
1590static int stm32_mdma_probe(struct platform_device *pdev)
1591{
1592	struct stm32_mdma_chan *chan;
1593	struct stm32_mdma_device *dmadev;
1594	struct dma_device *dd;
1595	struct device_node *of_node;
1596	struct reset_control *rst;
1597	u32 nr_channels, nr_requests;
1598	int i, count, ret;
1599
1600	of_node = pdev->dev.of_node;
1601	if (!of_node)
1602		return -ENODEV;
1603
1604	ret = device_property_read_u32(&pdev->dev, "dma-channels",
1605				       &nr_channels);
1606	if (ret) {
1607		nr_channels = STM32_MDMA_MAX_CHANNELS;
1608		dev_warn(&pdev->dev, "MDMA defaulting on %i channels\n",
1609			 nr_channels);
1610	}
1611
1612	ret = device_property_read_u32(&pdev->dev, "dma-requests",
1613				       &nr_requests);
1614	if (ret) {
1615		nr_requests = STM32_MDMA_MAX_REQUESTS;
1616		dev_warn(&pdev->dev, "MDMA defaulting on %i request lines\n",
1617			 nr_requests);
1618	}
1619
1620	count = device_property_count_u32(&pdev->dev, "st,ahb-addr-masks");
1621	if (count < 0)
1622		count = 0;
1623
1624	dmadev = devm_kzalloc(&pdev->dev,
1625			      struct_size(dmadev, ahb_addr_masks, count),
1626			      GFP_KERNEL);
1627	if (!dmadev)
1628		return -ENOMEM;
1629	dmadev->nr_ahb_addr_masks = count;
1630
1631	dmadev->nr_channels = nr_channels;
1632	dmadev->nr_requests = nr_requests;
1633	device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks",
1634				       dmadev->ahb_addr_masks,
1635				       count);
1636
1637	dmadev->base = devm_platform_ioremap_resource(pdev, 0);
1638	if (IS_ERR(dmadev->base))
1639		return PTR_ERR(dmadev->base);
1640
1641	dmadev->clk = devm_clk_get(&pdev->dev, NULL);
1642	if (IS_ERR(dmadev->clk))
1643		return dev_err_probe(&pdev->dev, PTR_ERR(dmadev->clk),
1644				     "Missing clock controller\n");
1645
1646	ret = clk_prepare_enable(dmadev->clk);
1647	if (ret < 0) {
1648		dev_err(&pdev->dev, "clk_prep_enable error: %d\n", ret);
1649		return ret;
1650	}
1651
1652	rst = devm_reset_control_get(&pdev->dev, NULL);
1653	if (IS_ERR(rst)) {
1654		ret = PTR_ERR(rst);
1655		if (ret == -EPROBE_DEFER)
1656			goto err_clk;
1657	} else {
1658		reset_control_assert(rst);
1659		udelay(2);
1660		reset_control_deassert(rst);
1661	}
1662
1663	dd = &dmadev->ddev;
1664	dma_cap_set(DMA_SLAVE, dd->cap_mask);
1665	dma_cap_set(DMA_PRIVATE, dd->cap_mask);
1666	dma_cap_set(DMA_CYCLIC, dd->cap_mask);
1667	dma_cap_set(DMA_MEMCPY, dd->cap_mask);
1668	dd->device_alloc_chan_resources = stm32_mdma_alloc_chan_resources;
1669	dd->device_free_chan_resources = stm32_mdma_free_chan_resources;
1670	dd->device_tx_status = stm32_mdma_tx_status;
1671	dd->device_issue_pending = stm32_mdma_issue_pending;
1672	dd->device_prep_slave_sg = stm32_mdma_prep_slave_sg;
1673	dd->device_prep_dma_cyclic = stm32_mdma_prep_dma_cyclic;
1674	dd->device_prep_dma_memcpy = stm32_mdma_prep_dma_memcpy;
1675	dd->device_config = stm32_mdma_slave_config;
1676	dd->device_pause = stm32_mdma_pause;
1677	dd->device_resume = stm32_mdma_resume;
1678	dd->device_terminate_all = stm32_mdma_terminate_all;
1679	dd->device_synchronize = stm32_mdma_synchronize;
1680	dd->descriptor_reuse = true;
1681
1682	dd->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1683		BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1684		BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1685		BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1686	dd->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1687		BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1688		BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1689		BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1690	dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) |
1691		BIT(DMA_MEM_TO_MEM);
1692	dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1693	dd->max_burst = STM32_MDMA_MAX_BURST;
1694	dd->dev = &pdev->dev;
1695	INIT_LIST_HEAD(&dd->channels);
1696
1697	for (i = 0; i < dmadev->nr_channels; i++) {
1698		chan = &dmadev->chan[i];
1699		chan->id = i;
1700
1701		if (stm32_mdma_read(dmadev, STM32_MDMA_CCR(i)) & STM32_MDMA_CCR_SM)
1702			dmadev->chan_reserved |= BIT(i);
1703
1704		chan->vchan.desc_free = stm32_mdma_desc_free;
1705		vchan_init(&chan->vchan, dd);
1706	}
1707
1708	dmadev->irq = platform_get_irq(pdev, 0);
1709	if (dmadev->irq < 0) {
1710		ret = dmadev->irq;
1711		goto err_clk;
1712	}
1713
1714	ret = devm_request_irq(&pdev->dev, dmadev->irq, stm32_mdma_irq_handler,
1715			       0, dev_name(&pdev->dev), dmadev);
1716	if (ret) {
1717		dev_err(&pdev->dev, "failed to request IRQ\n");
1718		goto err_clk;
1719	}
1720
1721	ret = dmaenginem_async_device_register(dd);
1722	if (ret)
1723		goto err_clk;
1724
1725	ret = of_dma_controller_register(of_node, stm32_mdma_of_xlate, dmadev);
1726	if (ret < 0) {
1727		dev_err(&pdev->dev,
1728			"STM32 MDMA DMA OF registration failed %d\n", ret);
1729		goto err_clk;
1730	}
1731
1732	platform_set_drvdata(pdev, dmadev);
1733	pm_runtime_set_active(&pdev->dev);
1734	pm_runtime_enable(&pdev->dev);
1735	pm_runtime_get_noresume(&pdev->dev);
1736	pm_runtime_put(&pdev->dev);
1737
1738	dev_info(&pdev->dev, "STM32 MDMA driver registered\n");
1739
1740	return 0;
1741
1742err_clk:
1743	clk_disable_unprepare(dmadev->clk);
1744
1745	return ret;
1746}
1747
1748#ifdef CONFIG_PM
1749static int stm32_mdma_runtime_suspend(struct device *dev)
1750{
1751	struct stm32_mdma_device *dmadev = dev_get_drvdata(dev);
1752
1753	clk_disable_unprepare(dmadev->clk);
1754
1755	return 0;
1756}
1757
1758static int stm32_mdma_runtime_resume(struct device *dev)
1759{
1760	struct stm32_mdma_device *dmadev = dev_get_drvdata(dev);
1761	int ret;
1762
1763	ret = clk_prepare_enable(dmadev->clk);
1764	if (ret) {
1765		dev_err(dev, "failed to prepare_enable clock\n");
1766		return ret;
1767	}
1768
1769	return 0;
1770}
1771#endif
1772
1773#ifdef CONFIG_PM_SLEEP
1774static int stm32_mdma_pm_suspend(struct device *dev)
1775{
1776	struct stm32_mdma_device *dmadev = dev_get_drvdata(dev);
1777	u32 ccr, id;
1778	int ret;
1779
1780	ret = pm_runtime_resume_and_get(dev);
1781	if (ret < 0)
1782		return ret;
1783
1784	for (id = 0; id < dmadev->nr_channels; id++) {
1785		ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(id));
1786		if (ccr & STM32_MDMA_CCR_EN) {
1787			dev_warn(dev, "Suspend is prevented by Chan %i\n", id);
1788			return -EBUSY;
1789		}
1790	}
1791
1792	pm_runtime_put_sync(dev);
1793
1794	pm_runtime_force_suspend(dev);
1795
1796	return 0;
1797}
1798
1799static int stm32_mdma_pm_resume(struct device *dev)
1800{
1801	return pm_runtime_force_resume(dev);
1802}
1803#endif
1804
1805static const struct dev_pm_ops stm32_mdma_pm_ops = {
1806	SET_SYSTEM_SLEEP_PM_OPS(stm32_mdma_pm_suspend, stm32_mdma_pm_resume)
1807	SET_RUNTIME_PM_OPS(stm32_mdma_runtime_suspend,
1808			   stm32_mdma_runtime_resume, NULL)
1809};
1810
1811static struct platform_driver stm32_mdma_driver = {
1812	.probe = stm32_mdma_probe,
1813	.driver = {
1814		.name = "stm32-mdma",
1815		.of_match_table = stm32_mdma_of_match,
1816		.pm = &stm32_mdma_pm_ops,
1817	},
1818};
1819
1820static int __init stm32_mdma_init(void)
1821{
1822	return platform_driver_register(&stm32_mdma_driver);
1823}
1824
1825subsys_initcall(stm32_mdma_init);
1826
1827MODULE_DESCRIPTION("Driver for STM32 MDMA controller");
1828MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>");
1829MODULE_AUTHOR("Pierre-Yves Mordret <pierre-yves.mordret@st.com>");