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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Xilinx ZynqMP DPDMA Engine driver
   4 *
   5 * Copyright (C) 2015 - 2020 Xilinx, Inc.
   6 *
   7 * Author: Hyun Woo Kwon <hyun.kwon@xilinx.com>
   8 */
   9
  10#include <linux/bitfield.h>
  11#include <linux/bits.h>
  12#include <linux/clk.h>
  13#include <linux/delay.h>
  14#include <linux/dmaengine.h>
  15#include <linux/dmapool.h>
  16#include <linux/interrupt.h>
  17#include <linux/module.h>
  18#include <linux/of.h>
  19#include <linux/of_dma.h>
  20#include <linux/platform_device.h>
  21#include <linux/sched.h>
  22#include <linux/slab.h>
  23#include <linux/spinlock.h>
  24#include <linux/wait.h>
  25
  26#include <dt-bindings/dma/xlnx-zynqmp-dpdma.h>
  27
  28#include "../dmaengine.h"
  29#include "../virt-dma.h"
  30
  31/* DPDMA registers */
  32#define XILINX_DPDMA_ERR_CTRL				0x000
  33#define XILINX_DPDMA_ISR				0x004
  34#define XILINX_DPDMA_IMR				0x008
  35#define XILINX_DPDMA_IEN				0x00c
  36#define XILINX_DPDMA_IDS				0x010
  37#define XILINX_DPDMA_INTR_DESC_DONE(n)			BIT((n) + 0)
  38#define XILINX_DPDMA_INTR_DESC_DONE_MASK		GENMASK(5, 0)
  39#define XILINX_DPDMA_INTR_NO_OSTAND(n)			BIT((n) + 6)
  40#define XILINX_DPDMA_INTR_NO_OSTAND_MASK		GENMASK(11, 6)
  41#define XILINX_DPDMA_INTR_AXI_ERR(n)			BIT((n) + 12)
  42#define XILINX_DPDMA_INTR_AXI_ERR_MASK			GENMASK(17, 12)
  43#define XILINX_DPDMA_INTR_DESC_ERR(n)			BIT((n) + 16)
  44#define XILINX_DPDMA_INTR_DESC_ERR_MASK			GENMASK(23, 18)
  45#define XILINX_DPDMA_INTR_WR_CMD_FIFO_FULL		BIT(24)
  46#define XILINX_DPDMA_INTR_WR_DATA_FIFO_FULL		BIT(25)
  47#define XILINX_DPDMA_INTR_AXI_4K_CROSS			BIT(26)
  48#define XILINX_DPDMA_INTR_VSYNC				BIT(27)
  49#define XILINX_DPDMA_INTR_CHAN_ERR_MASK			0x00041000
  50#define XILINX_DPDMA_INTR_CHAN_ERR			0x00fff000
  51#define XILINX_DPDMA_INTR_GLOBAL_ERR			0x07000000
  52#define XILINX_DPDMA_INTR_ERR_ALL			0x07fff000
  53#define XILINX_DPDMA_INTR_CHAN_MASK			0x00041041
  54#define XILINX_DPDMA_INTR_GLOBAL_MASK			0x0f000000
  55#define XILINX_DPDMA_INTR_ALL				0x0fffffff
  56#define XILINX_DPDMA_EISR				0x014
  57#define XILINX_DPDMA_EIMR				0x018
  58#define XILINX_DPDMA_EIEN				0x01c
  59#define XILINX_DPDMA_EIDS				0x020
  60#define XILINX_DPDMA_EINTR_INV_APB			BIT(0)
  61#define XILINX_DPDMA_EINTR_RD_AXI_ERR(n)		BIT((n) + 1)
  62#define XILINX_DPDMA_EINTR_RD_AXI_ERR_MASK		GENMASK(6, 1)
  63#define XILINX_DPDMA_EINTR_PRE_ERR(n)			BIT((n) + 7)
  64#define XILINX_DPDMA_EINTR_PRE_ERR_MASK			GENMASK(12, 7)
  65#define XILINX_DPDMA_EINTR_CRC_ERR(n)			BIT((n) + 13)
  66#define XILINX_DPDMA_EINTR_CRC_ERR_MASK			GENMASK(18, 13)
  67#define XILINX_DPDMA_EINTR_WR_AXI_ERR(n)		BIT((n) + 19)
  68#define XILINX_DPDMA_EINTR_WR_AXI_ERR_MASK		GENMASK(24, 19)
  69#define XILINX_DPDMA_EINTR_DESC_DONE_ERR(n)		BIT((n) + 25)
  70#define XILINX_DPDMA_EINTR_DESC_DONE_ERR_MASK		GENMASK(30, 25)
  71#define XILINX_DPDMA_EINTR_RD_CMD_FIFO_FULL		BIT(32)
  72#define XILINX_DPDMA_EINTR_CHAN_ERR_MASK		0x02082082
  73#define XILINX_DPDMA_EINTR_CHAN_ERR			0x7ffffffe
  74#define XILINX_DPDMA_EINTR_GLOBAL_ERR			0x80000001
  75#define XILINX_DPDMA_EINTR_ALL				0xffffffff
  76#define XILINX_DPDMA_CNTL				0x100
  77#define XILINX_DPDMA_GBL				0x104
  78#define XILINX_DPDMA_GBL_TRIG_MASK(n)			((n) << 0)
  79#define XILINX_DPDMA_GBL_RETRIG_MASK(n)			((n) << 6)
  80#define XILINX_DPDMA_ALC0_CNTL				0x108
  81#define XILINX_DPDMA_ALC0_STATUS			0x10c
  82#define XILINX_DPDMA_ALC0_MAX				0x110
  83#define XILINX_DPDMA_ALC0_MIN				0x114
  84#define XILINX_DPDMA_ALC0_ACC				0x118
  85#define XILINX_DPDMA_ALC0_ACC_TRAN			0x11c
  86#define XILINX_DPDMA_ALC1_CNTL				0x120
  87#define XILINX_DPDMA_ALC1_STATUS			0x124
  88#define XILINX_DPDMA_ALC1_MAX				0x128
  89#define XILINX_DPDMA_ALC1_MIN				0x12c
  90#define XILINX_DPDMA_ALC1_ACC				0x130
  91#define XILINX_DPDMA_ALC1_ACC_TRAN			0x134
  92
  93/* Channel register */
  94#define XILINX_DPDMA_CH_BASE				0x200
  95#define XILINX_DPDMA_CH_OFFSET				0x100
  96#define XILINX_DPDMA_CH_DESC_START_ADDRE		0x000
  97#define XILINX_DPDMA_CH_DESC_START_ADDRE_MASK		GENMASK(15, 0)
  98#define XILINX_DPDMA_CH_DESC_START_ADDR			0x004
  99#define XILINX_DPDMA_CH_DESC_NEXT_ADDRE			0x008
 100#define XILINX_DPDMA_CH_DESC_NEXT_ADDR			0x00c
 101#define XILINX_DPDMA_CH_PYLD_CUR_ADDRE			0x010
 102#define XILINX_DPDMA_CH_PYLD_CUR_ADDR			0x014
 103#define XILINX_DPDMA_CH_CNTL				0x018
 104#define XILINX_DPDMA_CH_CNTL_ENABLE			BIT(0)
 105#define XILINX_DPDMA_CH_CNTL_PAUSE			BIT(1)
 106#define XILINX_DPDMA_CH_CNTL_QOS_DSCR_WR_MASK		GENMASK(5, 2)
 107#define XILINX_DPDMA_CH_CNTL_QOS_DSCR_RD_MASK		GENMASK(9, 6)
 108#define XILINX_DPDMA_CH_CNTL_QOS_DATA_RD_MASK		GENMASK(13, 10)
 109#define XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS		11
 110#define XILINX_DPDMA_CH_STATUS				0x01c
 111#define XILINX_DPDMA_CH_STATUS_OTRAN_CNT_MASK		GENMASK(24, 21)
 112#define XILINX_DPDMA_CH_VDO				0x020
 113#define XILINX_DPDMA_CH_PYLD_SZ				0x024
 114#define XILINX_DPDMA_CH_DESC_ID				0x028
 115
 116/* DPDMA descriptor fields */
 117#define XILINX_DPDMA_DESC_CONTROL_PREEMBLE		0xa5
 118#define XILINX_DPDMA_DESC_CONTROL_COMPLETE_INTR		BIT(8)
 119#define XILINX_DPDMA_DESC_CONTROL_DESC_UPDATE		BIT(9)
 120#define XILINX_DPDMA_DESC_CONTROL_IGNORE_DONE		BIT(10)
 121#define XILINX_DPDMA_DESC_CONTROL_FRAG_MODE		BIT(18)
 122#define XILINX_DPDMA_DESC_CONTROL_LAST			BIT(19)
 123#define XILINX_DPDMA_DESC_CONTROL_ENABLE_CRC		BIT(20)
 124#define XILINX_DPDMA_DESC_CONTROL_LAST_OF_FRAME		BIT(21)
 125#define XILINX_DPDMA_DESC_ID_MASK			GENMASK(15, 0)
 126#define XILINX_DPDMA_DESC_HSIZE_STRIDE_HSIZE_MASK	GENMASK(17, 0)
 127#define XILINX_DPDMA_DESC_HSIZE_STRIDE_STRIDE_MASK	GENMASK(31, 18)
 128#define XILINX_DPDMA_DESC_ADDR_EXT_NEXT_ADDR_MASK	GENMASK(15, 0)
 129#define XILINX_DPDMA_DESC_ADDR_EXT_SRC_ADDR_MASK	GENMASK(31, 16)
 130
 131#define XILINX_DPDMA_ALIGN_BYTES			256
 132#define XILINX_DPDMA_LINESIZE_ALIGN_BITS		128
 133
 134#define XILINX_DPDMA_NUM_CHAN				6
 135
 136struct xilinx_dpdma_chan;
 137
 138/**
 139 * struct xilinx_dpdma_hw_desc - DPDMA hardware descriptor
 140 * @control: control configuration field
 141 * @desc_id: descriptor ID
 142 * @xfer_size: transfer size
 143 * @hsize_stride: horizontal size and stride
 144 * @timestamp_lsb: LSB of time stamp
 145 * @timestamp_msb: MSB of time stamp
 146 * @addr_ext: upper 16 bit of 48 bit address (next_desc and src_addr)
 147 * @next_desc: next descriptor 32 bit address
 148 * @src_addr: payload source address (1st page, 32 LSB)
 149 * @addr_ext_23: payload source address (3nd and 3rd pages, 16 LSBs)
 150 * @addr_ext_45: payload source address (4th and 5th pages, 16 LSBs)
 151 * @src_addr2: payload source address (2nd page, 32 LSB)
 152 * @src_addr3: payload source address (3rd page, 32 LSB)
 153 * @src_addr4: payload source address (4th page, 32 LSB)
 154 * @src_addr5: payload source address (5th page, 32 LSB)
 155 * @crc: descriptor CRC
 156 */
 157struct xilinx_dpdma_hw_desc {
 158	u32 control;
 159	u32 desc_id;
 160	u32 xfer_size;
 161	u32 hsize_stride;
 162	u32 timestamp_lsb;
 163	u32 timestamp_msb;
 164	u32 addr_ext;
 165	u32 next_desc;
 166	u32 src_addr;
 167	u32 addr_ext_23;
 168	u32 addr_ext_45;
 169	u32 src_addr2;
 170	u32 src_addr3;
 171	u32 src_addr4;
 172	u32 src_addr5;
 173	u32 crc;
 174} __aligned(XILINX_DPDMA_ALIGN_BYTES);
 175
 176/**
 177 * struct xilinx_dpdma_sw_desc - DPDMA software descriptor
 178 * @hw: DPDMA hardware descriptor
 179 * @node: list node for software descriptors
 180 * @dma_addr: DMA address of the software descriptor
 181 */
 182struct xilinx_dpdma_sw_desc {
 183	struct xilinx_dpdma_hw_desc hw;
 184	struct list_head node;
 185	dma_addr_t dma_addr;
 186};
 187
 188/**
 189 * struct xilinx_dpdma_tx_desc - DPDMA transaction descriptor
 190 * @vdesc: virtual DMA descriptor
 191 * @chan: DMA channel
 192 * @descriptors: list of software descriptors
 193 * @error: an error has been detected with this descriptor
 194 */
 195struct xilinx_dpdma_tx_desc {
 196	struct virt_dma_desc vdesc;
 197	struct xilinx_dpdma_chan *chan;
 198	struct list_head descriptors;
 199	bool error;
 200};
 201
 202#define to_dpdma_tx_desc(_desc) \
 203	container_of(_desc, struct xilinx_dpdma_tx_desc, vdesc)
 204
 205/**
 206 * struct xilinx_dpdma_chan - DPDMA channel
 207 * @vchan: virtual DMA channel
 208 * @reg: register base address
 209 * @id: channel ID
 210 * @wait_to_stop: queue to wait for outstanding transacitons before stopping
 211 * @running: true if the channel is running
 212 * @first_frame: flag for the first frame of stream
 213 * @video_group: flag if multi-channel operation is needed for video channels
 214 * @lock: lock to access struct xilinx_dpdma_chan
 215 * @desc_pool: descriptor allocation pool
 216 * @err_task: error IRQ bottom half handler
 217 * @desc: References to descriptors being processed
 218 * @desc.pending: Descriptor schedule to the hardware, pending execution
 219 * @desc.active: Descriptor being executed by the hardware
 220 * @xdev: DPDMA device
 221 */
 222struct xilinx_dpdma_chan {
 223	struct virt_dma_chan vchan;
 224	void __iomem *reg;
 225	unsigned int id;
 226
 227	wait_queue_head_t wait_to_stop;
 228	bool running;
 229	bool first_frame;
 230	bool video_group;
 231
 232	spinlock_t lock; /* lock to access struct xilinx_dpdma_chan */
 233	struct dma_pool *desc_pool;
 234	struct tasklet_struct err_task;
 235
 236	struct {
 237		struct xilinx_dpdma_tx_desc *pending;
 238		struct xilinx_dpdma_tx_desc *active;
 239	} desc;
 240
 241	struct xilinx_dpdma_device *xdev;
 242};
 243
 244#define to_xilinx_chan(_chan) \
 245	container_of(_chan, struct xilinx_dpdma_chan, vchan.chan)
 246
 247/**
 248 * struct xilinx_dpdma_device - DPDMA device
 249 * @common: generic dma device structure
 250 * @reg: register base address
 251 * @dev: generic device structure
 252 * @irq: the interrupt number
 253 * @axi_clk: axi clock
 254 * @chan: DPDMA channels
 255 * @ext_addr: flag for 64 bit system (48 bit addressing)
 256 */
 257struct xilinx_dpdma_device {
 258	struct dma_device common;
 259	void __iomem *reg;
 260	struct device *dev;
 261	int irq;
 262
 263	struct clk *axi_clk;
 264	struct xilinx_dpdma_chan *chan[XILINX_DPDMA_NUM_CHAN];
 265
 266	bool ext_addr;
 267};
 268
 269/* -----------------------------------------------------------------------------
 270 * I/O Accessors
 271 */
 272
 273static inline u32 dpdma_read(void __iomem *base, u32 offset)
 274{
 275	return ioread32(base + offset);
 276}
 277
 278static inline void dpdma_write(void __iomem *base, u32 offset, u32 val)
 279{
 280	iowrite32(val, base + offset);
 281}
 282
 283static inline void dpdma_clr(void __iomem *base, u32 offset, u32 clr)
 284{
 285	dpdma_write(base, offset, dpdma_read(base, offset) & ~clr);
 286}
 287
 288static inline void dpdma_set(void __iomem *base, u32 offset, u32 set)
 289{
 290	dpdma_write(base, offset, dpdma_read(base, offset) | set);
 291}
 292
 293/* -----------------------------------------------------------------------------
 294 * Descriptor Operations
 295 */
 296
 297/**
 298 * xilinx_dpdma_sw_desc_set_dma_addrs - Set DMA addresses in the descriptor
 299 * @xdev: DPDMA device
 300 * @sw_desc: The software descriptor in which to set DMA addresses
 301 * @prev: The previous descriptor
 302 * @dma_addr: array of dma addresses
 303 * @num_src_addr: number of addresses in @dma_addr
 304 *
 305 * Set all the DMA addresses in the hardware descriptor corresponding to @dev
 306 * from @dma_addr. If a previous descriptor is specified in @prev, its next
 307 * descriptor DMA address is set to the DMA address of @sw_desc. @prev may be
 308 * identical to @sw_desc for cyclic transfers.
 309 */
 310static void xilinx_dpdma_sw_desc_set_dma_addrs(struct xilinx_dpdma_device *xdev,
 311					       struct xilinx_dpdma_sw_desc *sw_desc,
 312					       struct xilinx_dpdma_sw_desc *prev,
 313					       dma_addr_t dma_addr[],
 314					       unsigned int num_src_addr)
 315{
 316	struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
 317	unsigned int i;
 318
 319	hw_desc->src_addr = lower_32_bits(dma_addr[0]);
 320	if (xdev->ext_addr)
 321		hw_desc->addr_ext |=
 322			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_SRC_ADDR_MASK,
 323				   upper_32_bits(dma_addr[0]));
 324
 325	for (i = 1; i < num_src_addr; i++) {
 326		u32 *addr = &hw_desc->src_addr2;
 327
 328		addr[i-1] = lower_32_bits(dma_addr[i]);
 329
 330		if (xdev->ext_addr) {
 331			u32 *addr_ext = &hw_desc->addr_ext_23;
 332			u32 addr_msb;
 333
 334			addr_msb = upper_32_bits(dma_addr[i]) & GENMASK(15, 0);
 335			addr_msb <<= 16 * ((i - 1) % 2);
 336			addr_ext[(i - 1) / 2] |= addr_msb;
 337		}
 338	}
 339
 340	if (!prev)
 341		return;
 342
 343	prev->hw.next_desc = lower_32_bits(sw_desc->dma_addr);
 344	if (xdev->ext_addr)
 345		prev->hw.addr_ext |=
 346			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_NEXT_ADDR_MASK,
 347				   upper_32_bits(sw_desc->dma_addr));
 348}
 349
 350/**
 351 * xilinx_dpdma_chan_alloc_sw_desc - Allocate a software descriptor
 352 * @chan: DPDMA channel
 353 *
 354 * Allocate a software descriptor from the channel's descriptor pool.
 355 *
 356 * Return: a software descriptor or NULL.
 357 */
 358static struct xilinx_dpdma_sw_desc *
 359xilinx_dpdma_chan_alloc_sw_desc(struct xilinx_dpdma_chan *chan)
 360{
 361	struct xilinx_dpdma_sw_desc *sw_desc;
 362	dma_addr_t dma_addr;
 363
 364	sw_desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &dma_addr);
 365	if (!sw_desc)
 366		return NULL;
 367
 368	sw_desc->dma_addr = dma_addr;
 369
 370	return sw_desc;
 371}
 372
 373/**
 374 * xilinx_dpdma_chan_free_sw_desc - Free a software descriptor
 375 * @chan: DPDMA channel
 376 * @sw_desc: software descriptor to free
 377 *
 378 * Free a software descriptor from the channel's descriptor pool.
 379 */
 380static void
 381xilinx_dpdma_chan_free_sw_desc(struct xilinx_dpdma_chan *chan,
 382			       struct xilinx_dpdma_sw_desc *sw_desc)
 383{
 384	dma_pool_free(chan->desc_pool, sw_desc, sw_desc->dma_addr);
 385}
 386
 387/**
 388 * xilinx_dpdma_chan_dump_tx_desc - Dump a tx descriptor
 389 * @chan: DPDMA channel
 390 * @tx_desc: tx descriptor to dump
 391 *
 392 * Dump contents of a tx descriptor
 393 */
 394static void xilinx_dpdma_chan_dump_tx_desc(struct xilinx_dpdma_chan *chan,
 395					   struct xilinx_dpdma_tx_desc *tx_desc)
 396{
 397	struct xilinx_dpdma_sw_desc *sw_desc;
 398	struct device *dev = chan->xdev->dev;
 399	unsigned int i = 0;
 400
 401	dev_dbg(dev, "------- TX descriptor dump start -------\n");
 402	dev_dbg(dev, "------- channel ID = %d -------\n", chan->id);
 403
 404	list_for_each_entry(sw_desc, &tx_desc->descriptors, node) {
 405		struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
 406
 407		dev_dbg(dev, "------- HW descriptor %d -------\n", i++);
 408		dev_dbg(dev, "descriptor DMA addr: %pad\n", &sw_desc->dma_addr);
 409		dev_dbg(dev, "control: 0x%08x\n", hw_desc->control);
 410		dev_dbg(dev, "desc_id: 0x%08x\n", hw_desc->desc_id);
 411		dev_dbg(dev, "xfer_size: 0x%08x\n", hw_desc->xfer_size);
 412		dev_dbg(dev, "hsize_stride: 0x%08x\n", hw_desc->hsize_stride);
 413		dev_dbg(dev, "timestamp_lsb: 0x%08x\n", hw_desc->timestamp_lsb);
 414		dev_dbg(dev, "timestamp_msb: 0x%08x\n", hw_desc->timestamp_msb);
 415		dev_dbg(dev, "addr_ext: 0x%08x\n", hw_desc->addr_ext);
 416		dev_dbg(dev, "next_desc: 0x%08x\n", hw_desc->next_desc);
 417		dev_dbg(dev, "src_addr: 0x%08x\n", hw_desc->src_addr);
 418		dev_dbg(dev, "addr_ext_23: 0x%08x\n", hw_desc->addr_ext_23);
 419		dev_dbg(dev, "addr_ext_45: 0x%08x\n", hw_desc->addr_ext_45);
 420		dev_dbg(dev, "src_addr2: 0x%08x\n", hw_desc->src_addr2);
 421		dev_dbg(dev, "src_addr3: 0x%08x\n", hw_desc->src_addr3);
 422		dev_dbg(dev, "src_addr4: 0x%08x\n", hw_desc->src_addr4);
 423		dev_dbg(dev, "src_addr5: 0x%08x\n", hw_desc->src_addr5);
 424		dev_dbg(dev, "crc: 0x%08x\n", hw_desc->crc);
 425	}
 426
 427	dev_dbg(dev, "------- TX descriptor dump end -------\n");
 428}
 429
 430/**
 431 * xilinx_dpdma_chan_alloc_tx_desc - Allocate a transaction descriptor
 432 * @chan: DPDMA channel
 433 *
 434 * Allocate a tx descriptor.
 435 *
 436 * Return: a tx descriptor or NULL.
 437 */
 438static struct xilinx_dpdma_tx_desc *
 439xilinx_dpdma_chan_alloc_tx_desc(struct xilinx_dpdma_chan *chan)
 440{
 441	struct xilinx_dpdma_tx_desc *tx_desc;
 442
 443	tx_desc = kzalloc(sizeof(*tx_desc), GFP_NOWAIT);
 444	if (!tx_desc)
 445		return NULL;
 446
 447	INIT_LIST_HEAD(&tx_desc->descriptors);
 448	tx_desc->chan = chan;
 449	tx_desc->error = false;
 450
 451	return tx_desc;
 452}
 453
 454/**
 455 * xilinx_dpdma_chan_free_tx_desc - Free a virtual DMA descriptor
 456 * @vdesc: virtual DMA descriptor
 457 *
 458 * Free the virtual DMA descriptor @vdesc including its software descriptors.
 459 */
 460static void xilinx_dpdma_chan_free_tx_desc(struct virt_dma_desc *vdesc)
 461{
 462	struct xilinx_dpdma_sw_desc *sw_desc, *next;
 463	struct xilinx_dpdma_tx_desc *desc;
 464
 465	if (!vdesc)
 466		return;
 467
 468	desc = to_dpdma_tx_desc(vdesc);
 469
 470	list_for_each_entry_safe(sw_desc, next, &desc->descriptors, node) {
 471		list_del(&sw_desc->node);
 472		xilinx_dpdma_chan_free_sw_desc(desc->chan, sw_desc);
 473	}
 474
 475	kfree(desc);
 476}
 477
 478/**
 479 * xilinx_dpdma_chan_prep_interleaved_dma - Prepare an interleaved dma
 480 *					    descriptor
 481 * @chan: DPDMA channel
 482 * @xt: dma interleaved template
 483 *
 484 * Prepare a tx descriptor including internal software/hardware descriptors
 485 * based on @xt.
 486 *
 487 * Return: A DPDMA TX descriptor on success, or NULL.
 488 */
 489static struct xilinx_dpdma_tx_desc *
 490xilinx_dpdma_chan_prep_interleaved_dma(struct xilinx_dpdma_chan *chan,
 491				       struct dma_interleaved_template *xt)
 492{
 493	struct xilinx_dpdma_tx_desc *tx_desc;
 494	struct xilinx_dpdma_sw_desc *sw_desc;
 495	struct xilinx_dpdma_hw_desc *hw_desc;
 496	size_t hsize = xt->sgl[0].size;
 497	size_t stride = hsize + xt->sgl[0].icg;
 498
 499	if (!IS_ALIGNED(xt->src_start, XILINX_DPDMA_ALIGN_BYTES)) {
 500		dev_err(chan->xdev->dev, "buffer should be aligned at %d B\n",
 501			XILINX_DPDMA_ALIGN_BYTES);
 502		return NULL;
 503	}
 504
 505	tx_desc = xilinx_dpdma_chan_alloc_tx_desc(chan);
 506	if (!tx_desc)
 507		return NULL;
 508
 509	sw_desc = xilinx_dpdma_chan_alloc_sw_desc(chan);
 510	if (!sw_desc) {
 511		xilinx_dpdma_chan_free_tx_desc(&tx_desc->vdesc);
 512		return NULL;
 513	}
 514
 515	xilinx_dpdma_sw_desc_set_dma_addrs(chan->xdev, sw_desc, sw_desc,
 516					   &xt->src_start, 1);
 517
 518	hw_desc = &sw_desc->hw;
 519	hsize = ALIGN(hsize, XILINX_DPDMA_LINESIZE_ALIGN_BITS / 8);
 520	hw_desc->xfer_size = hsize * xt->numf;
 521	hw_desc->hsize_stride =
 522		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_HSIZE_MASK, hsize) |
 523		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_STRIDE_MASK,
 524			   stride / 16);
 525	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_PREEMBLE;
 526	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_COMPLETE_INTR;
 527	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_IGNORE_DONE;
 528	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_LAST_OF_FRAME;
 529
 530	list_add_tail(&sw_desc->node, &tx_desc->descriptors);
 531
 532	return tx_desc;
 533}
 534
 535/* -----------------------------------------------------------------------------
 536 * DPDMA Channel Operations
 537 */
 538
 539/**
 540 * xilinx_dpdma_chan_enable - Enable the channel
 541 * @chan: DPDMA channel
 542 *
 543 * Enable the channel and its interrupts. Set the QoS values for video class.
 544 */
 545static void xilinx_dpdma_chan_enable(struct xilinx_dpdma_chan *chan)
 546{
 547	u32 reg;
 548
 549	reg = (XILINX_DPDMA_INTR_CHAN_MASK << chan->id)
 550	    | XILINX_DPDMA_INTR_GLOBAL_MASK;
 551	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
 552	reg = (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id)
 553	    | XILINX_DPDMA_INTR_GLOBAL_ERR;
 554	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
 555
 556	reg = XILINX_DPDMA_CH_CNTL_ENABLE
 557	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_WR_MASK,
 558			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
 559	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_RD_MASK,
 560			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
 561	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DATA_RD_MASK,
 562			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS);
 563	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, reg);
 564}
 565
 566/**
 567 * xilinx_dpdma_chan_disable - Disable the channel
 568 * @chan: DPDMA channel
 569 *
 570 * Disable the channel and its interrupts.
 571 */
 572static void xilinx_dpdma_chan_disable(struct xilinx_dpdma_chan *chan)
 573{
 574	u32 reg;
 575
 576	reg = XILINX_DPDMA_INTR_CHAN_MASK << chan->id;
 577	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
 578	reg = XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id;
 579	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
 580
 581	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_ENABLE);
 582}
 583
 584/**
 585 * xilinx_dpdma_chan_pause - Pause the channel
 586 * @chan: DPDMA channel
 587 *
 588 * Pause the channel.
 589 */
 590static void xilinx_dpdma_chan_pause(struct xilinx_dpdma_chan *chan)
 591{
 592	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
 593}
 594
 595/**
 596 * xilinx_dpdma_chan_unpause - Unpause the channel
 597 * @chan: DPDMA channel
 598 *
 599 * Unpause the channel.
 600 */
 601static void xilinx_dpdma_chan_unpause(struct xilinx_dpdma_chan *chan)
 602{
 603	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
 604}
 605
 606static u32 xilinx_dpdma_chan_video_group_ready(struct xilinx_dpdma_chan *chan)
 607{
 608	struct xilinx_dpdma_device *xdev = chan->xdev;
 609	u32 channels = 0;
 610	unsigned int i;
 611
 612	for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
 613		if (xdev->chan[i]->video_group && !xdev->chan[i]->running)
 614			return 0;
 615
 616		if (xdev->chan[i]->video_group)
 617			channels |= BIT(i);
 618	}
 619
 620	return channels;
 621}
 622
 623/**
 624 * xilinx_dpdma_chan_queue_transfer - Queue the next transfer
 625 * @chan: DPDMA channel
 626 *
 627 * Queue the next descriptor, if any, to the hardware. If the channel is
 628 * stopped, start it first. Otherwise retrigger it with the next descriptor.
 629 */
 630static void xilinx_dpdma_chan_queue_transfer(struct xilinx_dpdma_chan *chan)
 631{
 632	struct xilinx_dpdma_device *xdev = chan->xdev;
 633	struct xilinx_dpdma_sw_desc *sw_desc;
 634	struct xilinx_dpdma_tx_desc *desc;
 635	struct virt_dma_desc *vdesc;
 636	u32 reg, channels;
 637
 638	lockdep_assert_held(&chan->lock);
 639
 640	if (chan->desc.pending)
 641		return;
 642
 643	if (!chan->running) {
 644		xilinx_dpdma_chan_unpause(chan);
 645		xilinx_dpdma_chan_enable(chan);
 646		chan->first_frame = true;
 647		chan->running = true;
 648	}
 649
 650	if (chan->video_group)
 651		channels = xilinx_dpdma_chan_video_group_ready(chan);
 652	else
 653		channels = BIT(chan->id);
 654
 655	if (!channels)
 656		return;
 657
 658	vdesc = vchan_next_desc(&chan->vchan);
 659	if (!vdesc)
 660		return;
 661
 662	desc = to_dpdma_tx_desc(vdesc);
 663	chan->desc.pending = desc;
 664	list_del(&desc->vdesc.node);
 665
 666	/*
 667	 * Assign the cookie to descriptors in this transaction. Only 16 bit
 668	 * will be used, but it should be enough.
 669	 */
 670	list_for_each_entry(sw_desc, &desc->descriptors, node)
 671		sw_desc->hw.desc_id = desc->vdesc.tx.cookie;
 672
 673	sw_desc = list_first_entry(&desc->descriptors,
 674				   struct xilinx_dpdma_sw_desc, node);
 675	dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR,
 676		    lower_32_bits(sw_desc->dma_addr));
 677	if (xdev->ext_addr)
 678		dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE,
 679			    FIELD_PREP(XILINX_DPDMA_CH_DESC_START_ADDRE_MASK,
 680				       upper_32_bits(sw_desc->dma_addr)));
 681
 682	if (chan->first_frame)
 683		reg = XILINX_DPDMA_GBL_TRIG_MASK(channels);
 684	else
 685		reg = XILINX_DPDMA_GBL_RETRIG_MASK(channels);
 686
 687	chan->first_frame = false;
 688
 689	dpdma_write(xdev->reg, XILINX_DPDMA_GBL, reg);
 690}
 691
 692/**
 693 * xilinx_dpdma_chan_ostand - Number of outstanding transactions
 694 * @chan: DPDMA channel
 695 *
 696 * Read and return the number of outstanding transactions from register.
 697 *
 698 * Return: Number of outstanding transactions from the status register.
 699 */
 700static u32 xilinx_dpdma_chan_ostand(struct xilinx_dpdma_chan *chan)
 701{
 702	return FIELD_GET(XILINX_DPDMA_CH_STATUS_OTRAN_CNT_MASK,
 703			 dpdma_read(chan->reg, XILINX_DPDMA_CH_STATUS));
 704}
 705
 706/**
 707 * xilinx_dpdma_chan_no_ostand - Notify no outstanding transaction event
 708 * @chan: DPDMA channel
 709 *
 710 * Notify waiters for no outstanding event, so waiters can stop the channel
 711 * safely. This function is supposed to be called when 'no outstanding'
 712 * interrupt is generated. The 'no outstanding' interrupt is disabled and
 713 * should be re-enabled when this event is handled. If the channel status
 714 * register still shows some number of outstanding transactions, the interrupt
 715 * remains enabled.
 716 *
 717 * Return: 0 on success. On failure, -EWOULDBLOCK if there's still outstanding
 718 * transaction(s).
 719 */
 720static int xilinx_dpdma_chan_notify_no_ostand(struct xilinx_dpdma_chan *chan)
 721{
 722	u32 cnt;
 723
 724	cnt = xilinx_dpdma_chan_ostand(chan);
 725	if (cnt) {
 726		dev_dbg(chan->xdev->dev, "%d outstanding transactions\n", cnt);
 727		return -EWOULDBLOCK;
 728	}
 729
 730	/* Disable 'no outstanding' interrupt */
 731	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IDS,
 732		    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
 733	wake_up(&chan->wait_to_stop);
 734
 735	return 0;
 736}
 737
 738/**
 739 * xilinx_dpdma_chan_wait_no_ostand - Wait for the no outstanding irq
 740 * @chan: DPDMA channel
 741 *
 742 * Wait for the no outstanding transaction interrupt. This functions can sleep
 743 * for 50ms.
 744 *
 745 * Return: 0 on success. On failure, -ETIMEOUT for time out, or the error code
 746 * from wait_event_interruptible_timeout().
 747 */
 748static int xilinx_dpdma_chan_wait_no_ostand(struct xilinx_dpdma_chan *chan)
 749{
 750	int ret;
 751
 752	/* Wait for a no outstanding transaction interrupt upto 50msec */
 753	ret = wait_event_interruptible_timeout(chan->wait_to_stop,
 754					       !xilinx_dpdma_chan_ostand(chan),
 755					       msecs_to_jiffies(50));
 756	if (ret > 0) {
 757		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
 758			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
 759		return 0;
 760	}
 761
 762	dev_err(chan->xdev->dev, "not ready to stop: %d trans\n",
 763		xilinx_dpdma_chan_ostand(chan));
 764
 765	if (ret == 0)
 766		return -ETIMEDOUT;
 767
 768	return ret;
 769}
 770
 771/**
 772 * xilinx_dpdma_chan_poll_no_ostand - Poll the outstanding transaction status
 773 * @chan: DPDMA channel
 774 *
 775 * Poll the outstanding transaction status, and return when there's no
 776 * outstanding transaction. This functions can be used in the interrupt context
 777 * or where the atomicity is required. Calling thread may wait more than 50ms.
 778 *
 779 * Return: 0 on success, or -ETIMEDOUT.
 780 */
 781static int xilinx_dpdma_chan_poll_no_ostand(struct xilinx_dpdma_chan *chan)
 782{
 783	u32 cnt, loop = 50000;
 784
 785	/* Poll at least for 50ms (20 fps). */
 786	do {
 787		cnt = xilinx_dpdma_chan_ostand(chan);
 788		udelay(1);
 789	} while (loop-- > 0 && cnt);
 790
 791	if (loop) {
 792		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
 793			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
 794		return 0;
 795	}
 796
 797	dev_err(chan->xdev->dev, "not ready to stop: %d trans\n",
 798		xilinx_dpdma_chan_ostand(chan));
 799
 800	return -ETIMEDOUT;
 801}
 802
 803/**
 804 * xilinx_dpdma_chan_stop - Stop the channel
 805 * @chan: DPDMA channel
 806 *
 807 * Stop a previously paused channel by first waiting for completion of all
 808 * outstanding transaction and then disabling the channel.
 809 *
 810 * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
 811 */
 812static int xilinx_dpdma_chan_stop(struct xilinx_dpdma_chan *chan)
 813{
 814	unsigned long flags;
 815	int ret;
 816
 817	ret = xilinx_dpdma_chan_wait_no_ostand(chan);
 818	if (ret)
 819		return ret;
 820
 821	spin_lock_irqsave(&chan->lock, flags);
 822	xilinx_dpdma_chan_disable(chan);
 823	chan->running = false;
 824	spin_unlock_irqrestore(&chan->lock, flags);
 825
 826	return 0;
 827}
 828
 829/**
 830 * xilinx_dpdma_chan_done_irq - Handle hardware descriptor completion
 831 * @chan: DPDMA channel
 832 *
 833 * Handle completion of the currently active descriptor (@chan->desc.active). As
 834 * we currently support cyclic transfers only, this just invokes the cyclic
 835 * callback. The descriptor will be completed at the VSYNC interrupt when a new
 836 * descriptor replaces it.
 837 */
 838static void xilinx_dpdma_chan_done_irq(struct xilinx_dpdma_chan *chan)
 839{
 840	struct xilinx_dpdma_tx_desc *active = chan->desc.active;
 841	unsigned long flags;
 842
 843	spin_lock_irqsave(&chan->lock, flags);
 844
 845	if (active)
 846		vchan_cyclic_callback(&active->vdesc);
 847	else
 848		dev_warn(chan->xdev->dev,
 849			 "DONE IRQ with no active descriptor!\n");
 850
 851	spin_unlock_irqrestore(&chan->lock, flags);
 852}
 853
 854/**
 855 * xilinx_dpdma_chan_vsync_irq - Handle hardware descriptor scheduling
 856 * @chan: DPDMA channel
 857 *
 858 * At VSYNC the active descriptor may have been replaced by the pending
 859 * descriptor. Detect this through the DESC_ID and perform appropriate
 860 * bookkeeping.
 861 */
 862static void xilinx_dpdma_chan_vsync_irq(struct  xilinx_dpdma_chan *chan)
 863{
 864	struct xilinx_dpdma_tx_desc *pending;
 865	struct xilinx_dpdma_sw_desc *sw_desc;
 866	unsigned long flags;
 867	u32 desc_id;
 868
 869	spin_lock_irqsave(&chan->lock, flags);
 870
 871	pending = chan->desc.pending;
 872	if (!chan->running || !pending)
 873		goto out;
 874
 875	desc_id = dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_ID);
 876
 877	/* If the retrigger raced with vsync, retry at the next frame. */
 878	sw_desc = list_first_entry(&pending->descriptors,
 879				   struct xilinx_dpdma_sw_desc, node);
 880	if (sw_desc->hw.desc_id != desc_id)
 881		goto out;
 882
 883	/*
 884	 * Complete the active descriptor, if any, promote the pending
 885	 * descriptor to active, and queue the next transfer, if any.
 886	 */
 887	if (chan->desc.active)
 888		vchan_cookie_complete(&chan->desc.active->vdesc);
 889	chan->desc.active = pending;
 890	chan->desc.pending = NULL;
 891
 892	xilinx_dpdma_chan_queue_transfer(chan);
 893
 894out:
 895	spin_unlock_irqrestore(&chan->lock, flags);
 896}
 897
 898/**
 899 * xilinx_dpdma_chan_err - Detect any channel error
 900 * @chan: DPDMA channel
 901 * @isr: masked Interrupt Status Register
 902 * @eisr: Error Interrupt Status Register
 903 *
 904 * Return: true if any channel error occurs, or false otherwise.
 905 */
 906static bool
 907xilinx_dpdma_chan_err(struct xilinx_dpdma_chan *chan, u32 isr, u32 eisr)
 908{
 909	if (!chan)
 910		return false;
 911
 912	if (chan->running &&
 913	    ((isr & (XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id)) ||
 914	    (eisr & (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id))))
 915		return true;
 916
 917	return false;
 918}
 919
 920/**
 921 * xilinx_dpdma_chan_handle_err - DPDMA channel error handling
 922 * @chan: DPDMA channel
 923 *
 924 * This function is called when any channel error or any global error occurs.
 925 * The function disables the paused channel by errors and determines
 926 * if the current active descriptor can be rescheduled depending on
 927 * the descriptor status.
 928 */
 929static void xilinx_dpdma_chan_handle_err(struct xilinx_dpdma_chan *chan)
 930{
 931	struct xilinx_dpdma_device *xdev = chan->xdev;
 932	struct xilinx_dpdma_tx_desc *active;
 933	unsigned long flags;
 934
 935	spin_lock_irqsave(&chan->lock, flags);
 936
 937	dev_dbg(xdev->dev, "cur desc addr = 0x%04x%08x\n",
 938		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE),
 939		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR));
 940	dev_dbg(xdev->dev, "cur payload addr = 0x%04x%08x\n",
 941		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDRE),
 942		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDR));
 943
 944	xilinx_dpdma_chan_disable(chan);
 945	chan->running = false;
 946
 947	if (!chan->desc.active)
 948		goto out_unlock;
 949
 950	active = chan->desc.active;
 951	chan->desc.active = NULL;
 952
 953	xilinx_dpdma_chan_dump_tx_desc(chan, active);
 954
 955	if (active->error)
 956		dev_dbg(xdev->dev, "repeated error on desc\n");
 957
 958	/* Reschedule if there's no new descriptor */
 959	if (!chan->desc.pending &&
 960	    list_empty(&chan->vchan.desc_issued)) {
 961		active->error = true;
 962		list_add_tail(&active->vdesc.node,
 963			      &chan->vchan.desc_issued);
 964	} else {
 965		xilinx_dpdma_chan_free_tx_desc(&active->vdesc);
 966	}
 967
 968out_unlock:
 969	spin_unlock_irqrestore(&chan->lock, flags);
 970}
 971
 972/* -----------------------------------------------------------------------------
 973 * DMA Engine Operations
 974 */
 975
 976static struct dma_async_tx_descriptor *
 977xilinx_dpdma_prep_interleaved_dma(struct dma_chan *dchan,
 978				  struct dma_interleaved_template *xt,
 979				  unsigned long flags)
 980{
 981	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
 982	struct xilinx_dpdma_tx_desc *desc;
 983
 984	if (xt->dir != DMA_MEM_TO_DEV)
 985		return NULL;
 986
 987	if (!xt->numf || !xt->sgl[0].size)
 988		return NULL;
 989
 990	if (!(flags & DMA_PREP_REPEAT) || !(flags & DMA_PREP_LOAD_EOT))
 991		return NULL;
 992
 993	desc = xilinx_dpdma_chan_prep_interleaved_dma(chan, xt);
 994	if (!desc)
 995		return NULL;
 996
 997	vchan_tx_prep(&chan->vchan, &desc->vdesc, flags | DMA_CTRL_ACK);
 998
 999	return &desc->vdesc.tx;
1000}
1001
1002/**
1003 * xilinx_dpdma_alloc_chan_resources - Allocate resources for the channel
1004 * @dchan: DMA channel
1005 *
1006 * Allocate a descriptor pool for the channel.
1007 *
1008 * Return: 0 on success, or -ENOMEM if failed to allocate a pool.
1009 */
1010static int xilinx_dpdma_alloc_chan_resources(struct dma_chan *dchan)
1011{
1012	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1013	size_t align = __alignof__(struct xilinx_dpdma_sw_desc);
1014
1015	chan->desc_pool = dma_pool_create(dev_name(chan->xdev->dev),
1016					  chan->xdev->dev,
1017					  sizeof(struct xilinx_dpdma_sw_desc),
1018					  align, 0);
1019	if (!chan->desc_pool) {
1020		dev_err(chan->xdev->dev,
1021			"failed to allocate a descriptor pool\n");
1022		return -ENOMEM;
1023	}
1024
1025	return 0;
1026}
1027
1028/**
1029 * xilinx_dpdma_free_chan_resources - Free all resources for the channel
1030 * @dchan: DMA channel
1031 *
1032 * Free resources associated with the virtual DMA channel, and destroy the
1033 * descriptor pool.
1034 */
1035static void xilinx_dpdma_free_chan_resources(struct dma_chan *dchan)
1036{
1037	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1038
1039	vchan_free_chan_resources(&chan->vchan);
1040
1041	dma_pool_destroy(chan->desc_pool);
1042	chan->desc_pool = NULL;
1043}
1044
1045static void xilinx_dpdma_issue_pending(struct dma_chan *dchan)
1046{
1047	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1048	unsigned long flags;
1049
1050	spin_lock_irqsave(&chan->vchan.lock, flags);
1051	if (vchan_issue_pending(&chan->vchan))
1052		xilinx_dpdma_chan_queue_transfer(chan);
1053	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1054}
1055
1056static int xilinx_dpdma_config(struct dma_chan *dchan,
1057			       struct dma_slave_config *config)
1058{
1059	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1060	unsigned long flags;
1061
1062	/*
1063	 * The destination address doesn't need to be specified as the DPDMA is
1064	 * hardwired to the destination (the DP controller). The transfer
1065	 * width, burst size and port window size are thus meaningless, they're
1066	 * fixed both on the DPDMA side and on the DP controller side.
1067	 */
1068
1069	spin_lock_irqsave(&chan->lock, flags);
1070
1071	/*
1072	 * Abuse the slave_id to indicate that the channel is part of a video
1073	 * group.
1074	 */
1075	if (chan->id <= ZYNQMP_DPDMA_VIDEO2)
1076		chan->video_group = config->slave_id != 0;
1077
1078	spin_unlock_irqrestore(&chan->lock, flags);
1079
1080	return 0;
1081}
1082
1083static int xilinx_dpdma_pause(struct dma_chan *dchan)
1084{
1085	xilinx_dpdma_chan_pause(to_xilinx_chan(dchan));
1086
1087	return 0;
1088}
1089
1090static int xilinx_dpdma_resume(struct dma_chan *dchan)
1091{
1092	xilinx_dpdma_chan_unpause(to_xilinx_chan(dchan));
1093
1094	return 0;
1095}
1096
1097/**
1098 * xilinx_dpdma_terminate_all - Terminate the channel and descriptors
1099 * @dchan: DMA channel
1100 *
1101 * Pause the channel without waiting for ongoing transfers to complete. Waiting
1102 * for completion is performed by xilinx_dpdma_synchronize() that will disable
1103 * the channel to complete the stop.
1104 *
1105 * All the descriptors associated with the channel that are guaranteed not to
1106 * be touched by the hardware. The pending and active descriptor are not
1107 * touched, and will be freed either upon completion, or by
1108 * xilinx_dpdma_synchronize().
1109 *
1110 * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
1111 */
1112static int xilinx_dpdma_terminate_all(struct dma_chan *dchan)
1113{
1114	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1115	struct xilinx_dpdma_device *xdev = chan->xdev;
1116	LIST_HEAD(descriptors);
1117	unsigned long flags;
1118	unsigned int i;
1119
1120	/* Pause the channel (including the whole video group if applicable). */
1121	if (chan->video_group) {
1122		for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
1123			if (xdev->chan[i]->video_group &&
1124			    xdev->chan[i]->running) {
1125				xilinx_dpdma_chan_pause(xdev->chan[i]);
1126				xdev->chan[i]->video_group = false;
1127			}
1128		}
1129	} else {
1130		xilinx_dpdma_chan_pause(chan);
1131	}
1132
1133	/* Gather all the descriptors we can free and free them. */
1134	spin_lock_irqsave(&chan->vchan.lock, flags);
1135	vchan_get_all_descriptors(&chan->vchan, &descriptors);
1136	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1137
1138	vchan_dma_desc_free_list(&chan->vchan, &descriptors);
1139
1140	return 0;
1141}
1142
1143/**
1144 * xilinx_dpdma_synchronize - Synchronize callback execution
1145 * @dchan: DMA channel
1146 *
1147 * Synchronizing callback execution ensures that all previously issued
1148 * transfers have completed and all associated callbacks have been called and
1149 * have returned.
1150 *
1151 * This function waits for the DMA channel to stop. It assumes it has been
1152 * paused by a previous call to dmaengine_terminate_async(), and that no new
1153 * pending descriptors have been issued with dma_async_issue_pending(). The
1154 * behaviour is undefined otherwise.
1155 */
1156static void xilinx_dpdma_synchronize(struct dma_chan *dchan)
1157{
1158	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1159	unsigned long flags;
1160
1161	xilinx_dpdma_chan_stop(chan);
1162
1163	spin_lock_irqsave(&chan->vchan.lock, flags);
1164	if (chan->desc.pending) {
1165		vchan_terminate_vdesc(&chan->desc.pending->vdesc);
1166		chan->desc.pending = NULL;
1167	}
1168	if (chan->desc.active) {
1169		vchan_terminate_vdesc(&chan->desc.active->vdesc);
1170		chan->desc.active = NULL;
1171	}
1172	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1173
1174	vchan_synchronize(&chan->vchan);
1175}
1176
1177/* -----------------------------------------------------------------------------
1178 * Interrupt and Tasklet Handling
1179 */
1180
1181/**
1182 * xilinx_dpdma_err - Detect any global error
1183 * @isr: Interrupt Status Register
1184 * @eisr: Error Interrupt Status Register
1185 *
1186 * Return: True if any global error occurs, or false otherwise.
1187 */
1188static bool xilinx_dpdma_err(u32 isr, u32 eisr)
1189{
1190	if (isr & XILINX_DPDMA_INTR_GLOBAL_ERR ||
1191	    eisr & XILINX_DPDMA_EINTR_GLOBAL_ERR)
1192		return true;
1193
1194	return false;
1195}
1196
1197/**
1198 * xilinx_dpdma_handle_err_irq - Handle DPDMA error interrupt
1199 * @xdev: DPDMA device
1200 * @isr: masked Interrupt Status Register
1201 * @eisr: Error Interrupt Status Register
1202 *
1203 * Handle if any error occurs based on @isr and @eisr. This function disables
1204 * corresponding error interrupts, and those should be re-enabled once handling
1205 * is done.
1206 */
1207static void xilinx_dpdma_handle_err_irq(struct xilinx_dpdma_device *xdev,
1208					u32 isr, u32 eisr)
1209{
1210	bool err = xilinx_dpdma_err(isr, eisr);
1211	unsigned int i;
1212
1213	dev_dbg_ratelimited(xdev->dev,
1214			    "error irq: isr = 0x%08x, eisr = 0x%08x\n",
1215			    isr, eisr);
1216
1217	/* Disable channel error interrupts until errors are handled. */
1218	dpdma_write(xdev->reg, XILINX_DPDMA_IDS,
1219		    isr & ~XILINX_DPDMA_INTR_GLOBAL_ERR);
1220	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS,
1221		    eisr & ~XILINX_DPDMA_EINTR_GLOBAL_ERR);
1222
1223	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1224		if (err || xilinx_dpdma_chan_err(xdev->chan[i], isr, eisr))
1225			tasklet_schedule(&xdev->chan[i]->err_task);
1226}
1227
1228/**
1229 * xilinx_dpdma_enable_irq - Enable interrupts
1230 * @xdev: DPDMA device
1231 *
1232 * Enable interrupts.
1233 */
1234static void xilinx_dpdma_enable_irq(struct xilinx_dpdma_device *xdev)
1235{
1236	dpdma_write(xdev->reg, XILINX_DPDMA_IEN, XILINX_DPDMA_INTR_ALL);
1237	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN, XILINX_DPDMA_EINTR_ALL);
1238}
1239
1240/**
1241 * xilinx_dpdma_disable_irq - Disable interrupts
1242 * @xdev: DPDMA device
1243 *
1244 * Disable interrupts.
1245 */
1246static void xilinx_dpdma_disable_irq(struct xilinx_dpdma_device *xdev)
1247{
1248	dpdma_write(xdev->reg, XILINX_DPDMA_IDS, XILINX_DPDMA_INTR_ERR_ALL);
1249	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS, XILINX_DPDMA_EINTR_ALL);
1250}
1251
1252/**
1253 * xilinx_dpdma_chan_err_task - Per channel tasklet for error handling
1254 * @data: tasklet data to be casted to DPDMA channel structure
1255 *
1256 * Per channel error handling tasklet. This function waits for the outstanding
1257 * transaction to complete and triggers error handling. After error handling,
1258 * re-enable channel error interrupts, and restart the channel if needed.
1259 */
1260static void xilinx_dpdma_chan_err_task(unsigned long data)
1261{
1262	struct xilinx_dpdma_chan *chan = (struct xilinx_dpdma_chan *)data;
1263	struct xilinx_dpdma_device *xdev = chan->xdev;
1264	unsigned long flags;
1265
1266	/* Proceed error handling even when polling fails. */
1267	xilinx_dpdma_chan_poll_no_ostand(chan);
1268
1269	xilinx_dpdma_chan_handle_err(chan);
1270
1271	dpdma_write(xdev->reg, XILINX_DPDMA_IEN,
1272		    XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id);
1273	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN,
1274		    XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id);
1275
1276	spin_lock_irqsave(&chan->lock, flags);
1277	xilinx_dpdma_chan_queue_transfer(chan);
1278	spin_unlock_irqrestore(&chan->lock, flags);
1279}
1280
1281static irqreturn_t xilinx_dpdma_irq_handler(int irq, void *data)
1282{
1283	struct xilinx_dpdma_device *xdev = data;
1284	unsigned long mask;
1285	unsigned int i;
1286	u32 status;
1287	u32 error;
1288
1289	status = dpdma_read(xdev->reg, XILINX_DPDMA_ISR);
1290	error = dpdma_read(xdev->reg, XILINX_DPDMA_EISR);
1291	if (!status && !error)
1292		return IRQ_NONE;
1293
1294	dpdma_write(xdev->reg, XILINX_DPDMA_ISR, status);
1295	dpdma_write(xdev->reg, XILINX_DPDMA_EISR, error);
1296
1297	if (status & XILINX_DPDMA_INTR_VSYNC) {
1298		/*
1299		 * There's a single VSYNC interrupt that needs to be processed
1300		 * by each running channel to update the active descriptor.
1301		 */
1302		for (i = 0; i < ARRAY_SIZE(xdev->chan); i++) {
1303			struct xilinx_dpdma_chan *chan = xdev->chan[i];
1304
1305			if (chan)
1306				xilinx_dpdma_chan_vsync_irq(chan);
1307		}
1308	}
1309
1310	mask = FIELD_GET(XILINX_DPDMA_INTR_DESC_DONE_MASK, status);
1311	if (mask) {
1312		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1313			xilinx_dpdma_chan_done_irq(xdev->chan[i]);
1314	}
1315
1316	mask = FIELD_GET(XILINX_DPDMA_INTR_NO_OSTAND_MASK, status);
1317	if (mask) {
1318		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1319			xilinx_dpdma_chan_notify_no_ostand(xdev->chan[i]);
1320	}
1321
1322	mask = status & XILINX_DPDMA_INTR_ERR_ALL;
1323	if (mask || error)
1324		xilinx_dpdma_handle_err_irq(xdev, mask, error);
1325
1326	return IRQ_HANDLED;
1327}
1328
1329/* -----------------------------------------------------------------------------
1330 * Initialization & Cleanup
1331 */
1332
1333static int xilinx_dpdma_chan_init(struct xilinx_dpdma_device *xdev,
1334				  unsigned int chan_id)
1335{
1336	struct xilinx_dpdma_chan *chan;
1337
1338	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
1339	if (!chan)
1340		return -ENOMEM;
1341
1342	chan->id = chan_id;
1343	chan->reg = xdev->reg + XILINX_DPDMA_CH_BASE
1344		  + XILINX_DPDMA_CH_OFFSET * chan->id;
1345	chan->running = false;
1346	chan->xdev = xdev;
1347
1348	spin_lock_init(&chan->lock);
1349	init_waitqueue_head(&chan->wait_to_stop);
1350
1351	tasklet_init(&chan->err_task, xilinx_dpdma_chan_err_task,
1352		     (unsigned long)chan);
1353
1354	chan->vchan.desc_free = xilinx_dpdma_chan_free_tx_desc;
1355	vchan_init(&chan->vchan, &xdev->common);
1356
1357	xdev->chan[chan->id] = chan;
1358
1359	return 0;
1360}
1361
1362static void xilinx_dpdma_chan_remove(struct xilinx_dpdma_chan *chan)
1363{
1364	if (!chan)
1365		return;
1366
1367	tasklet_kill(&chan->err_task);
1368	list_del(&chan->vchan.chan.device_node);
1369}
1370
1371static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
1372					    struct of_dma *ofdma)
1373{
1374	struct xilinx_dpdma_device *xdev = ofdma->of_dma_data;
1375	uint32_t chan_id = dma_spec->args[0];
1376
1377	if (chan_id >= ARRAY_SIZE(xdev->chan))
1378		return NULL;
1379
1380	if (!xdev->chan[chan_id])
1381		return NULL;
1382
1383	return dma_get_slave_channel(&xdev->chan[chan_id]->vchan.chan);
1384}
1385
1386static int xilinx_dpdma_probe(struct platform_device *pdev)
1387{
1388	struct xilinx_dpdma_device *xdev;
1389	struct dma_device *ddev;
1390	unsigned int i;
1391	int ret;
1392
1393	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
1394	if (!xdev)
1395		return -ENOMEM;
1396
1397	xdev->dev = &pdev->dev;
1398	xdev->ext_addr = sizeof(dma_addr_t) > 4;
1399
1400	INIT_LIST_HEAD(&xdev->common.channels);
1401
1402	platform_set_drvdata(pdev, xdev);
1403
1404	xdev->axi_clk = devm_clk_get(xdev->dev, "axi_clk");
1405	if (IS_ERR(xdev->axi_clk))
1406		return PTR_ERR(xdev->axi_clk);
1407
1408	xdev->reg = devm_platform_ioremap_resource(pdev, 0);
1409	if (IS_ERR(xdev->reg))
1410		return PTR_ERR(xdev->reg);
1411
1412	xdev->irq = platform_get_irq(pdev, 0);
1413	if (xdev->irq < 0) {
1414		dev_err(xdev->dev, "failed to get platform irq\n");
1415		return xdev->irq;
1416	}
1417
1418	ret = request_irq(xdev->irq, xilinx_dpdma_irq_handler, IRQF_SHARED,
1419			  dev_name(xdev->dev), xdev);
1420	if (ret) {
1421		dev_err(xdev->dev, "failed to request IRQ\n");
1422		return ret;
1423	}
1424
1425	ddev = &xdev->common;
1426	ddev->dev = &pdev->dev;
1427
1428	dma_cap_set(DMA_SLAVE, ddev->cap_mask);
1429	dma_cap_set(DMA_PRIVATE, ddev->cap_mask);
1430	dma_cap_set(DMA_INTERLEAVE, ddev->cap_mask);
1431	dma_cap_set(DMA_REPEAT, ddev->cap_mask);
1432	dma_cap_set(DMA_LOAD_EOT, ddev->cap_mask);
1433	ddev->copy_align = fls(XILINX_DPDMA_ALIGN_BYTES - 1);
1434
1435	ddev->device_alloc_chan_resources = xilinx_dpdma_alloc_chan_resources;
1436	ddev->device_free_chan_resources = xilinx_dpdma_free_chan_resources;
1437	ddev->device_prep_interleaved_dma = xilinx_dpdma_prep_interleaved_dma;
1438	/* TODO: Can we achieve better granularity ? */
1439	ddev->device_tx_status = dma_cookie_status;
1440	ddev->device_issue_pending = xilinx_dpdma_issue_pending;
1441	ddev->device_config = xilinx_dpdma_config;
1442	ddev->device_pause = xilinx_dpdma_pause;
1443	ddev->device_resume = xilinx_dpdma_resume;
1444	ddev->device_terminate_all = xilinx_dpdma_terminate_all;
1445	ddev->device_synchronize = xilinx_dpdma_synchronize;
1446	ddev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED);
1447	ddev->directions = BIT(DMA_MEM_TO_DEV);
1448	ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1449
1450	for (i = 0; i < ARRAY_SIZE(xdev->chan); ++i) {
1451		ret = xilinx_dpdma_chan_init(xdev, i);
1452		if (ret < 0) {
1453			dev_err(xdev->dev, "failed to initialize channel %u\n",
1454				i);
1455			goto error;
1456		}
1457	}
1458
1459	ret = clk_prepare_enable(xdev->axi_clk);
1460	if (ret) {
1461		dev_err(xdev->dev, "failed to enable the axi clock\n");
1462		goto error;
1463	}
1464
1465	ret = dma_async_device_register(ddev);
1466	if (ret) {
1467		dev_err(xdev->dev, "failed to register the dma device\n");
1468		goto error_dma_async;
1469	}
1470
1471	ret = of_dma_controller_register(xdev->dev->of_node,
1472					 of_dma_xilinx_xlate, ddev);
1473	if (ret) {
1474		dev_err(xdev->dev, "failed to register DMA to DT DMA helper\n");
1475		goto error_of_dma;
1476	}
1477
1478	xilinx_dpdma_enable_irq(xdev);
1479
1480	dev_info(&pdev->dev, "Xilinx DPDMA engine is probed\n");
1481
1482	return 0;
1483
1484error_of_dma:
1485	dma_async_device_unregister(ddev);
1486error_dma_async:
1487	clk_disable_unprepare(xdev->axi_clk);
1488error:
1489	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1490		xilinx_dpdma_chan_remove(xdev->chan[i]);
1491
1492	free_irq(xdev->irq, xdev);
1493
1494	return ret;
1495}
1496
1497static int xilinx_dpdma_remove(struct platform_device *pdev)
1498{
1499	struct xilinx_dpdma_device *xdev = platform_get_drvdata(pdev);
1500	unsigned int i;
1501
1502	/* Start by disabling the IRQ to avoid races during cleanup. */
1503	free_irq(xdev->irq, xdev);
1504
1505	xilinx_dpdma_disable_irq(xdev);
1506	of_dma_controller_free(pdev->dev.of_node);
1507	dma_async_device_unregister(&xdev->common);
1508	clk_disable_unprepare(xdev->axi_clk);
1509
1510	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1511		xilinx_dpdma_chan_remove(xdev->chan[i]);
1512
1513	return 0;
1514}
1515
1516static const struct of_device_id xilinx_dpdma_of_match[] = {
1517	{ .compatible = "xlnx,zynqmp-dpdma",},
1518	{ /* end of table */ },
1519};
1520MODULE_DEVICE_TABLE(of, xilinx_dpdma_of_match);
1521
1522static struct platform_driver xilinx_dpdma_driver = {
1523	.probe			= xilinx_dpdma_probe,
1524	.remove			= xilinx_dpdma_remove,
1525	.driver			= {
1526		.name		= "xilinx-zynqmp-dpdma",
1527		.of_match_table	= xilinx_dpdma_of_match,
1528	},
1529};
1530
1531module_platform_driver(xilinx_dpdma_driver);
1532
1533MODULE_AUTHOR("Xilinx, Inc.");
1534MODULE_DESCRIPTION("Xilinx ZynqMP DPDMA driver");
1535MODULE_LICENSE("GPL v2");