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v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems)
   4 *
   5 * Copyright (C) 2014 Atmel Corporation
   6 *
   7 * Author: Ludovic Desroches <ludovic.desroches@atmel.com>
 
 
 
 
 
 
 
 
 
 
 
 
   8 */
   9
  10#include <asm/barrier.h>
  11#include <dt-bindings/dma/at91.h>
  12#include <linux/clk.h>
  13#include <linux/dmaengine.h>
  14#include <linux/dmapool.h>
  15#include <linux/interrupt.h>
  16#include <linux/irq.h>
  17#include <linux/kernel.h>
  18#include <linux/list.h>
  19#include <linux/module.h>
  20#include <linux/of_dma.h>
  21#include <linux/of_platform.h>
  22#include <linux/platform_device.h>
  23#include <linux/pm.h>
  24#include <linux/pm_runtime.h>
  25
  26#include "dmaengine.h"
  27
  28/* Global registers */
  29#define AT_XDMAC_GTYPE		0x00	/* Global Type Register */
  30#define		AT_XDMAC_NB_CH(i)	(((i) & 0x1F) + 1)		/* Number of Channels Minus One */
  31#define		AT_XDMAC_FIFO_SZ(i)	(((i) >> 5) & 0x7FF)		/* Number of Bytes */
  32#define		AT_XDMAC_NB_REQ(i)	((((i) >> 16) & 0x3F) + 1)	/* Number of Peripheral Requests Minus One */
  33#define AT_XDMAC_GCFG		0x04	/* Global Configuration Register */
  34#define		AT_XDMAC_WRHP(i)		(((i) & 0xF) << 4)
  35#define		AT_XDMAC_WRMP(i)		(((i) & 0xF) << 8)
  36#define		AT_XDMAC_WRLP(i)		(((i) & 0xF) << 12)
  37#define		AT_XDMAC_RDHP(i)		(((i) & 0xF) << 16)
  38#define		AT_XDMAC_RDMP(i)		(((i) & 0xF) << 20)
  39#define		AT_XDMAC_RDLP(i)		(((i) & 0xF) << 24)
  40#define		AT_XDMAC_RDSG(i)		(((i) & 0xF) << 28)
  41#define AT_XDMAC_GCFG_M2M	(AT_XDMAC_RDLP(0xF) | AT_XDMAC_WRLP(0xF))
  42#define AT_XDMAC_GCFG_P2M	(AT_XDMAC_RDSG(0x1) | AT_XDMAC_RDHP(0x3) | \
  43				AT_XDMAC_WRHP(0x5))
  44#define AT_XDMAC_GWAC		0x08	/* Global Weighted Arbiter Configuration Register */
  45#define		AT_XDMAC_PW0(i)		(((i) & 0xF) << 0)
  46#define		AT_XDMAC_PW1(i)		(((i) & 0xF) << 4)
  47#define		AT_XDMAC_PW2(i)		(((i) & 0xF) << 8)
  48#define		AT_XDMAC_PW3(i)		(((i) & 0xF) << 12)
  49#define AT_XDMAC_GWAC_M2M	0
  50#define AT_XDMAC_GWAC_P2M	(AT_XDMAC_PW0(0xF) | AT_XDMAC_PW2(0xF))
  51
  52#define AT_XDMAC_GIE		0x0C	/* Global Interrupt Enable Register */
  53#define AT_XDMAC_GID		0x10	/* Global Interrupt Disable Register */
  54#define AT_XDMAC_GIM		0x14	/* Global Interrupt Mask Register */
  55#define AT_XDMAC_GIS		0x18	/* Global Interrupt Status Register */
  56#define AT_XDMAC_GE		0x1C	/* Global Channel Enable Register */
  57#define AT_XDMAC_GD		0x20	/* Global Channel Disable Register */
  58#define AT_XDMAC_GS		0x24	/* Global Channel Status Register */
 
 
 
 
 
 
 
  59#define AT_XDMAC_VERSION	0xFFC	/* XDMAC Version Register */
  60
  61/* Channel relative registers offsets */
  62#define AT_XDMAC_CIE		0x00	/* Channel Interrupt Enable Register */
  63#define		AT_XDMAC_CIE_BIE	BIT(0)	/* End of Block Interrupt Enable Bit */
  64#define		AT_XDMAC_CIE_LIE	BIT(1)	/* End of Linked List Interrupt Enable Bit */
  65#define		AT_XDMAC_CIE_DIE	BIT(2)	/* End of Disable Interrupt Enable Bit */
  66#define		AT_XDMAC_CIE_FIE	BIT(3)	/* End of Flush Interrupt Enable Bit */
  67#define		AT_XDMAC_CIE_RBEIE	BIT(4)	/* Read Bus Error Interrupt Enable Bit */
  68#define		AT_XDMAC_CIE_WBEIE	BIT(5)	/* Write Bus Error Interrupt Enable Bit */
  69#define		AT_XDMAC_CIE_ROIE	BIT(6)	/* Request Overflow Interrupt Enable Bit */
  70#define AT_XDMAC_CID		0x04	/* Channel Interrupt Disable Register */
  71#define		AT_XDMAC_CID_BID	BIT(0)	/* End of Block Interrupt Disable Bit */
  72#define		AT_XDMAC_CID_LID	BIT(1)	/* End of Linked List Interrupt Disable Bit */
  73#define		AT_XDMAC_CID_DID	BIT(2)	/* End of Disable Interrupt Disable Bit */
  74#define		AT_XDMAC_CID_FID	BIT(3)	/* End of Flush Interrupt Disable Bit */
  75#define		AT_XDMAC_CID_RBEID	BIT(4)	/* Read Bus Error Interrupt Disable Bit */
  76#define		AT_XDMAC_CID_WBEID	BIT(5)	/* Write Bus Error Interrupt Disable Bit */
  77#define		AT_XDMAC_CID_ROID	BIT(6)	/* Request Overflow Interrupt Disable Bit */
  78#define AT_XDMAC_CIM		0x08	/* Channel Interrupt Mask Register */
  79#define		AT_XDMAC_CIM_BIM	BIT(0)	/* End of Block Interrupt Mask Bit */
  80#define		AT_XDMAC_CIM_LIM	BIT(1)	/* End of Linked List Interrupt Mask Bit */
  81#define		AT_XDMAC_CIM_DIM	BIT(2)	/* End of Disable Interrupt Mask Bit */
  82#define		AT_XDMAC_CIM_FIM	BIT(3)	/* End of Flush Interrupt Mask Bit */
  83#define		AT_XDMAC_CIM_RBEIM	BIT(4)	/* Read Bus Error Interrupt Mask Bit */
  84#define		AT_XDMAC_CIM_WBEIM	BIT(5)	/* Write Bus Error Interrupt Mask Bit */
  85#define		AT_XDMAC_CIM_ROIM	BIT(6)	/* Request Overflow Interrupt Mask Bit */
  86#define AT_XDMAC_CIS		0x0C	/* Channel Interrupt Status Register */
  87#define		AT_XDMAC_CIS_BIS	BIT(0)	/* End of Block Interrupt Status Bit */
  88#define		AT_XDMAC_CIS_LIS	BIT(1)	/* End of Linked List Interrupt Status Bit */
  89#define		AT_XDMAC_CIS_DIS	BIT(2)	/* End of Disable Interrupt Status Bit */
  90#define		AT_XDMAC_CIS_FIS	BIT(3)	/* End of Flush Interrupt Status Bit */
  91#define		AT_XDMAC_CIS_RBEIS	BIT(4)	/* Read Bus Error Interrupt Status Bit */
  92#define		AT_XDMAC_CIS_WBEIS	BIT(5)	/* Write Bus Error Interrupt Status Bit */
  93#define		AT_XDMAC_CIS_ROIS	BIT(6)	/* Request Overflow Interrupt Status Bit */
  94#define AT_XDMAC_CSA		0x10	/* Channel Source Address Register */
  95#define AT_XDMAC_CDA		0x14	/* Channel Destination Address Register */
  96#define AT_XDMAC_CNDA		0x18	/* Channel Next Descriptor Address Register */
  97#define		AT_XDMAC_CNDA_NDAIF(i)	((i) & 0x1)			/* Channel x Next Descriptor Interface */
  98#define		AT_XDMAC_CNDA_NDA(i)	((i) & 0xfffffffc)		/* Channel x Next Descriptor Address */
  99#define AT_XDMAC_CNDC		0x1C	/* Channel Next Descriptor Control Register */
 100#define		AT_XDMAC_CNDC_NDE		(0x1 << 0)		/* Channel x Next Descriptor Enable */
 101#define		AT_XDMAC_CNDC_NDSUP		(0x1 << 1)		/* Channel x Next Descriptor Source Update */
 102#define		AT_XDMAC_CNDC_NDDUP		(0x1 << 2)		/* Channel x Next Descriptor Destination Update */
 103#define		AT_XDMAC_CNDC_NDVIEW_MASK	GENMASK(28, 27)
 104#define		AT_XDMAC_CNDC_NDVIEW_NDV0	(0x0 << 3)		/* Channel x Next Descriptor View 0 */
 105#define		AT_XDMAC_CNDC_NDVIEW_NDV1	(0x1 << 3)		/* Channel x Next Descriptor View 1 */
 106#define		AT_XDMAC_CNDC_NDVIEW_NDV2	(0x2 << 3)		/* Channel x Next Descriptor View 2 */
 107#define		AT_XDMAC_CNDC_NDVIEW_NDV3	(0x3 << 3)		/* Channel x Next Descriptor View 3 */
 108#define AT_XDMAC_CUBC		0x20	/* Channel Microblock Control Register */
 109#define AT_XDMAC_CBC		0x24	/* Channel Block Control Register */
 110#define AT_XDMAC_CC		0x28	/* Channel Configuration Register */
 111#define		AT_XDMAC_CC_TYPE	(0x1 << 0)	/* Channel Transfer Type */
 112#define			AT_XDMAC_CC_TYPE_MEM_TRAN	(0x0 << 0)	/* Memory to Memory Transfer */
 113#define			AT_XDMAC_CC_TYPE_PER_TRAN	(0x1 << 0)	/* Peripheral to Memory or Memory to Peripheral Transfer */
 114#define		AT_XDMAC_CC_MBSIZE_MASK	(0x3 << 1)
 115#define			AT_XDMAC_CC_MBSIZE_SINGLE	(0x0 << 1)
 116#define			AT_XDMAC_CC_MBSIZE_FOUR		(0x1 << 1)
 117#define			AT_XDMAC_CC_MBSIZE_EIGHT	(0x2 << 1)
 118#define			AT_XDMAC_CC_MBSIZE_SIXTEEN	(0x3 << 1)
 119#define		AT_XDMAC_CC_DSYNC	(0x1 << 4)	/* Channel Synchronization */
 120#define			AT_XDMAC_CC_DSYNC_PER2MEM	(0x0 << 4)
 121#define			AT_XDMAC_CC_DSYNC_MEM2PER	(0x1 << 4)
 122#define		AT_XDMAC_CC_PROT	(0x1 << 5)	/* Channel Protection */
 123#define			AT_XDMAC_CC_PROT_SEC		(0x0 << 5)
 124#define			AT_XDMAC_CC_PROT_UNSEC		(0x1 << 5)
 125#define		AT_XDMAC_CC_SWREQ	(0x1 << 6)	/* Channel Software Request Trigger */
 126#define			AT_XDMAC_CC_SWREQ_HWR_CONNECTED	(0x0 << 6)
 127#define			AT_XDMAC_CC_SWREQ_SWR_CONNECTED	(0x1 << 6)
 128#define		AT_XDMAC_CC_MEMSET	(0x1 << 7)	/* Channel Fill Block of memory */
 129#define			AT_XDMAC_CC_MEMSET_NORMAL_MODE	(0x0 << 7)
 130#define			AT_XDMAC_CC_MEMSET_HW_MODE	(0x1 << 7)
 131#define		AT_XDMAC_CC_CSIZE(i)	((0x7 & (i)) << 8)	/* Channel Chunk Size */
 132#define		AT_XDMAC_CC_DWIDTH_OFFSET	11
 133#define		AT_XDMAC_CC_DWIDTH_MASK	(0x3 << AT_XDMAC_CC_DWIDTH_OFFSET)
 134#define		AT_XDMAC_CC_DWIDTH(i)	((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET)	/* Channel Data Width */
 135#define			AT_XDMAC_CC_DWIDTH_BYTE		0x0
 136#define			AT_XDMAC_CC_DWIDTH_HALFWORD	0x1
 137#define			AT_XDMAC_CC_DWIDTH_WORD		0x2
 138#define			AT_XDMAC_CC_DWIDTH_DWORD	0x3
 139#define		AT_XDMAC_CC_SIF(i)	((0x1 & (i)) << 13)	/* Channel Source Interface Identifier */
 140#define		AT_XDMAC_CC_DIF(i)	((0x1 & (i)) << 14)	/* Channel Destination Interface Identifier */
 141#define		AT_XDMAC_CC_SAM_MASK	(0x3 << 16)	/* Channel Source Addressing Mode */
 142#define			AT_XDMAC_CC_SAM_FIXED_AM	(0x0 << 16)
 143#define			AT_XDMAC_CC_SAM_INCREMENTED_AM	(0x1 << 16)
 144#define			AT_XDMAC_CC_SAM_UBS_AM		(0x2 << 16)
 145#define			AT_XDMAC_CC_SAM_UBS_DS_AM	(0x3 << 16)
 146#define		AT_XDMAC_CC_DAM_MASK	(0x3 << 18)	/* Channel Source Addressing Mode */
 147#define			AT_XDMAC_CC_DAM_FIXED_AM	(0x0 << 18)
 148#define			AT_XDMAC_CC_DAM_INCREMENTED_AM	(0x1 << 18)
 149#define			AT_XDMAC_CC_DAM_UBS_AM		(0x2 << 18)
 150#define			AT_XDMAC_CC_DAM_UBS_DS_AM	(0x3 << 18)
 151#define		AT_XDMAC_CC_INITD	(0x1 << 21)	/* Channel Initialization Terminated (read only) */
 152#define			AT_XDMAC_CC_INITD_TERMINATED	(0x0 << 21)
 153#define			AT_XDMAC_CC_INITD_IN_PROGRESS	(0x1 << 21)
 154#define		AT_XDMAC_CC_RDIP	(0x1 << 22)	/* Read in Progress (read only) */
 155#define			AT_XDMAC_CC_RDIP_DONE		(0x0 << 22)
 156#define			AT_XDMAC_CC_RDIP_IN_PROGRESS	(0x1 << 22)
 157#define		AT_XDMAC_CC_WRIP	(0x1 << 23)	/* Write in Progress (read only) */
 158#define			AT_XDMAC_CC_WRIP_DONE		(0x0 << 23)
 159#define			AT_XDMAC_CC_WRIP_IN_PROGRESS	(0x1 << 23)
 160#define		AT_XDMAC_CC_PERID(i)	((0x7f & (i)) << 24)	/* Channel Peripheral Identifier */
 161#define AT_XDMAC_CDS_MSP	0x2C	/* Channel Data Stride Memory Set Pattern */
 162#define AT_XDMAC_CSUS		0x30	/* Channel Source Microblock Stride */
 163#define AT_XDMAC_CDUS		0x34	/* Channel Destination Microblock Stride */
 164
 
 
 165/* Microblock control members */
 166#define AT_XDMAC_MBR_UBC_UBLEN_MAX	0xFFFFFFUL	/* Maximum Microblock Length */
 167#define AT_XDMAC_MBR_UBC_NDE		(0x1 << 24)	/* Next Descriptor Enable */
 168#define AT_XDMAC_MBR_UBC_NSEN		(0x1 << 25)	/* Next Descriptor Source Update */
 169#define AT_XDMAC_MBR_UBC_NDEN		(0x1 << 26)	/* Next Descriptor Destination Update */
 170#define AT_XDMAC_MBR_UBC_NDV0		(0x0 << 27)	/* Next Descriptor View 0 */
 171#define AT_XDMAC_MBR_UBC_NDV1		(0x1 << 27)	/* Next Descriptor View 1 */
 172#define AT_XDMAC_MBR_UBC_NDV2		(0x2 << 27)	/* Next Descriptor View 2 */
 173#define AT_XDMAC_MBR_UBC_NDV3		(0x3 << 27)	/* Next Descriptor View 3 */
 174
 175#define AT_XDMAC_MAX_CHAN	0x20
 176#define AT_XDMAC_MAX_CSIZE	16	/* 16 data */
 177#define AT_XDMAC_MAX_DWIDTH	8	/* 64 bits */
 178#define AT_XDMAC_RESIDUE_MAX_RETRIES	5
 179
 180#define AT_XDMAC_DMA_BUSWIDTHS\
 181	(BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
 182	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\
 183	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\
 184	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\
 185	BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
 186
 187enum atc_status {
 188	AT_XDMAC_CHAN_IS_CYCLIC = 0,
 189	AT_XDMAC_CHAN_IS_PAUSED,
 190	AT_XDMAC_CHAN_IS_PAUSED_INTERNAL,
 191};
 192
 193struct at_xdmac_layout {
 194	/* Global Channel Read Suspend Register */
 195	u8				grs;
 196	/* Global Write Suspend Register */
 197	u8				gws;
 198	/* Global Channel Read Write Suspend Register */
 199	u8				grws;
 200	/* Global Channel Read Write Resume Register */
 201	u8				grwr;
 202	/* Global Channel Software Request Register */
 203	u8				gswr;
 204	/* Global channel Software Request Status Register */
 205	u8				gsws;
 206	/* Global Channel Software Flush Request Register */
 207	u8				gswf;
 208	/* Channel reg base */
 209	u8				chan_cc_reg_base;
 210	/* Source/Destination Interface must be specified or not */
 211	bool				sdif;
 212	/* AXI queue priority configuration supported */
 213	bool				axi_config;
 214};
 215
 216/* ----- Channels ----- */
 217struct at_xdmac_chan {
 218	struct dma_chan			chan;
 219	void __iomem			*ch_regs;
 220	u32				mask;		/* Channel Mask */
 221	u32				cfg;		/* Channel Configuration Register */
 222	u8				perid;		/* Peripheral ID */
 223	u8				perif;		/* Peripheral Interface */
 224	u8				memif;		/* Memory Interface */
 225	u32				save_cc;
 226	u32				save_cim;
 227	u32				save_cnda;
 228	u32				save_cndc;
 229	u32				irq_status;
 230	unsigned long			status;
 231	struct tasklet_struct		tasklet;
 232	struct dma_slave_config		sconfig;
 233
 234	spinlock_t			lock;
 235
 236	struct list_head		xfers_list;
 237	struct list_head		free_descs_list;
 238};
 239
 240
 241/* ----- Controller ----- */
 242struct at_xdmac {
 243	struct dma_device	dma;
 244	void __iomem		*regs;
 245	struct device		*dev;
 246	int			irq;
 247	struct clk		*clk;
 248	u32			save_gim;
 249	u32			save_gs;
 250	struct dma_pool		*at_xdmac_desc_pool;
 251	const struct at_xdmac_layout	*layout;
 252	struct at_xdmac_chan	chan[];
 253};
 254
 255
 256/* ----- Descriptors ----- */
 257
 258/* Linked List Descriptor */
 259struct at_xdmac_lld {
 260	u32 mbr_nda;	/* Next Descriptor Member */
 261	u32 mbr_ubc;	/* Microblock Control Member */
 262	u32 mbr_sa;	/* Source Address Member */
 263	u32 mbr_da;	/* Destination Address Member */
 264	u32 mbr_cfg;	/* Configuration Register */
 265	u32 mbr_bc;	/* Block Control Register */
 266	u32 mbr_ds;	/* Data Stride Register */
 267	u32 mbr_sus;	/* Source Microblock Stride Register */
 268	u32 mbr_dus;	/* Destination Microblock Stride Register */
 269};
 270
 271/* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */
 272struct at_xdmac_desc {
 273	struct at_xdmac_lld		lld;
 274	enum dma_transfer_direction	direction;
 275	struct dma_async_tx_descriptor	tx_dma_desc;
 276	struct list_head		desc_node;
 277	/* Following members are only used by the first descriptor */
 278	bool				active_xfer;
 279	unsigned int			xfer_size;
 280	struct list_head		descs_list;
 281	struct list_head		xfer_node;
 282} __aligned(sizeof(u64));
 283
 284static const struct at_xdmac_layout at_xdmac_sama5d4_layout = {
 285	.grs = 0x28,
 286	.gws = 0x2C,
 287	.grws = 0x30,
 288	.grwr = 0x34,
 289	.gswr = 0x38,
 290	.gsws = 0x3C,
 291	.gswf = 0x40,
 292	.chan_cc_reg_base = 0x50,
 293	.sdif = true,
 294	.axi_config = false,
 295};
 296
 297static const struct at_xdmac_layout at_xdmac_sama7g5_layout = {
 298	.grs = 0x30,
 299	.gws = 0x38,
 300	.grws = 0x40,
 301	.grwr = 0x44,
 302	.gswr = 0x48,
 303	.gsws = 0x4C,
 304	.gswf = 0x50,
 305	.chan_cc_reg_base = 0x60,
 306	.sdif = false,
 307	.axi_config = true,
 308};
 309
 310static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb)
 311{
 312	return atxdmac->regs + (atxdmac->layout->chan_cc_reg_base + chan_nb * 0x40);
 313}
 314
 315#define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg))
 316#define at_xdmac_write(atxdmac, reg, value) \
 317	writel_relaxed((value), (atxdmac)->regs + (reg))
 318
 319#define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg))
 320#define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg))
 321
 322static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan)
 323{
 324	return container_of(dchan, struct at_xdmac_chan, chan);
 325}
 326
 327static struct device *chan2dev(struct dma_chan *chan)
 328{
 329	return &chan->dev->device;
 330}
 331
 332static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev)
 333{
 334	return container_of(ddev, struct at_xdmac, dma);
 335}
 336
 337static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd)
 338{
 339	return container_of(txd, struct at_xdmac_desc, tx_dma_desc);
 340}
 341
 342static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan)
 343{
 344	return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
 345}
 346
 347static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan)
 348{
 349	return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
 350}
 351
 352static inline int at_xdmac_chan_is_paused_internal(struct at_xdmac_chan *atchan)
 353{
 354	return test_bit(AT_XDMAC_CHAN_IS_PAUSED_INTERNAL, &atchan->status);
 355}
 356
 357static inline bool at_xdmac_chan_is_peripheral_xfer(u32 cfg)
 358{
 359	return cfg & AT_XDMAC_CC_TYPE_PER_TRAN;
 360}
 
 
 361
 362static inline u8 at_xdmac_get_dwidth(u32 cfg)
 363{
 364	return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
 365};
 366
 367static unsigned int init_nr_desc_per_channel = 64;
 368module_param(init_nr_desc_per_channel, uint, 0644);
 369MODULE_PARM_DESC(init_nr_desc_per_channel,
 370		 "initial descriptors per channel (default: 64)");
 371
 372
 373static void at_xdmac_runtime_suspend_descriptors(struct at_xdmac_chan *atchan)
 374{
 375	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
 376	struct at_xdmac_desc	*desc, *_desc;
 377
 378	list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
 379		if (!desc->active_xfer)
 380			continue;
 381
 382		pm_runtime_mark_last_busy(atxdmac->dev);
 383		pm_runtime_put_autosuspend(atxdmac->dev);
 384	}
 385}
 386
 387static int at_xdmac_runtime_resume_descriptors(struct at_xdmac_chan *atchan)
 388{
 389	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
 390	struct at_xdmac_desc	*desc, *_desc;
 391	int			ret;
 392
 393	list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
 394		if (!desc->active_xfer)
 395			continue;
 396
 397		ret = pm_runtime_resume_and_get(atxdmac->dev);
 398		if (ret < 0)
 399			return ret;
 400	}
 401
 402	return 0;
 403}
 404
 405static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan)
 406{
 407	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
 408	int			ret;
 409
 410	ret = pm_runtime_resume_and_get(atxdmac->dev);
 411	if (ret < 0)
 412		return false;
 413
 414	ret = !!(at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask);
 415
 416	pm_runtime_mark_last_busy(atxdmac->dev);
 417	pm_runtime_put_autosuspend(atxdmac->dev);
 418
 419	return ret;
 420}
 421
 422static void at_xdmac_off(struct at_xdmac *atxdmac, bool suspend_descriptors)
 423{
 424	struct dma_chan		*chan, *_chan;
 425	struct at_xdmac_chan	*atchan;
 426	int			ret;
 427
 428	ret = pm_runtime_resume_and_get(atxdmac->dev);
 429	if (ret < 0)
 430		return;
 431
 432	at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L);
 433
 434	/* Wait that all chans are disabled. */
 435	while (at_xdmac_read(atxdmac, AT_XDMAC_GS))
 436		cpu_relax();
 437
 438	at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L);
 439
 440	/* Decrement runtime PM ref counter for each active descriptor. */
 441	if (!list_empty(&atxdmac->dma.channels) && suspend_descriptors) {
 442		list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels,
 443					 device_node) {
 444			atchan = to_at_xdmac_chan(chan);
 445			at_xdmac_runtime_suspend_descriptors(atchan);
 446		}
 447	}
 448
 449	pm_runtime_mark_last_busy(atxdmac->dev);
 450	pm_runtime_put_autosuspend(atxdmac->dev);
 451}
 452
 453/* Call with lock hold. */
 454static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
 455				struct at_xdmac_desc *first)
 456{
 457	struct at_xdmac	*atxdmac = to_at_xdmac(atchan->chan.device);
 458	u32		reg;
 459	int		ret;
 460
 461	ret = pm_runtime_resume_and_get(atxdmac->dev);
 462	if (ret < 0)
 463		return;
 464
 465	dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
 466
 
 
 
 467	/* Set transfer as active to not try to start it again. */
 468	first->active_xfer = true;
 469
 470	/* Tell xdmac where to get the first descriptor. */
 471	reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys);
 472	if (atxdmac->layout->sdif)
 473		reg |= AT_XDMAC_CNDA_NDAIF(atchan->memif);
 474
 475	at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
 476
 477	/*
 478	 * When doing non cyclic transfer we need to use the next
 479	 * descriptor view 2 since some fields of the configuration register
 480	 * depend on transfer size and src/dest addresses.
 481	 */
 482	if (at_xdmac_chan_is_cyclic(atchan))
 483		reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
 484	else if ((first->lld.mbr_ubc &
 485		  AT_XDMAC_CNDC_NDVIEW_MASK) == AT_XDMAC_MBR_UBC_NDV3)
 486		reg = AT_XDMAC_CNDC_NDVIEW_NDV3;
 487	else
 488		reg = AT_XDMAC_CNDC_NDVIEW_NDV2;
 489	/*
 490	 * Even if the register will be updated from the configuration in the
 491	 * descriptor when using view 2 or higher, the PROT bit won't be set
 492	 * properly. This bit can be modified only by using the channel
 493	 * configuration register.
 494	 */
 495	at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
 496
 497	reg |= AT_XDMAC_CNDC_NDDUP
 498	       | AT_XDMAC_CNDC_NDSUP
 499	       | AT_XDMAC_CNDC_NDE;
 500	at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg);
 501
 502	dev_vdbg(chan2dev(&atchan->chan),
 503		 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
 504		 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
 505		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
 506		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
 507		 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
 508		 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
 509		 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 510
 511	at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
 512	reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE;
 513	/*
 514	 * Request Overflow Error is only for peripheral synchronized transfers
 515	 */
 516	if (at_xdmac_chan_is_peripheral_xfer(first->lld.mbr_cfg))
 517		reg |= AT_XDMAC_CIE_ROIE;
 518
 519	/*
 520	 * There is no end of list when doing cyclic dma, we need to get
 521	 * an interrupt after each periods.
 522	 */
 523	if (at_xdmac_chan_is_cyclic(atchan))
 524		at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
 525				    reg | AT_XDMAC_CIE_BIE);
 526	else
 527		at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
 528				    reg | AT_XDMAC_CIE_LIE);
 529	at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask);
 530	dev_vdbg(chan2dev(&atchan->chan),
 531		 "%s: enable channel (0x%08x)\n", __func__, atchan->mask);
 532	wmb();
 533	at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
 534
 535	dev_vdbg(chan2dev(&atchan->chan),
 536		 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
 537		 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
 538		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
 539		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
 540		 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
 541		 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
 542		 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 
 543}
 544
 545static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx)
 546{
 547	struct at_xdmac_desc	*desc = txd_to_at_desc(tx);
 548	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(tx->chan);
 549	dma_cookie_t		cookie;
 550	unsigned long		irqflags;
 551
 552	spin_lock_irqsave(&atchan->lock, irqflags);
 553	cookie = dma_cookie_assign(tx);
 554
 555	list_add_tail(&desc->xfer_node, &atchan->xfers_list);
 556	spin_unlock_irqrestore(&atchan->lock, irqflags);
 557
 558	dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n",
 559		 __func__, atchan, desc);
 
 
 
 560
 
 561	return cookie;
 562}
 563
 564static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan,
 565						 gfp_t gfp_flags)
 566{
 567	struct at_xdmac_desc	*desc;
 568	struct at_xdmac		*atxdmac = to_at_xdmac(chan->device);
 569	dma_addr_t		phys;
 570
 571	desc = dma_pool_zalloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys);
 572	if (desc) {
 
 573		INIT_LIST_HEAD(&desc->descs_list);
 574		dma_async_tx_descriptor_init(&desc->tx_dma_desc, chan);
 575		desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit;
 576		desc->tx_dma_desc.phys = phys;
 577	}
 578
 579	return desc;
 580}
 581
 582static void at_xdmac_init_used_desc(struct at_xdmac_desc *desc)
 583{
 584	memset(&desc->lld, 0, sizeof(desc->lld));
 585	INIT_LIST_HEAD(&desc->descs_list);
 586	desc->direction = DMA_TRANS_NONE;
 587	desc->xfer_size = 0;
 588	desc->active_xfer = false;
 589}
 590
 591/* Call must be protected by lock. */
 592static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan)
 593{
 594	struct at_xdmac_desc *desc;
 595
 596	if (list_empty(&atchan->free_descs_list)) {
 597		desc = at_xdmac_alloc_desc(&atchan->chan, GFP_NOWAIT);
 598	} else {
 599		desc = list_first_entry(&atchan->free_descs_list,
 600					struct at_xdmac_desc, desc_node);
 601		list_del(&desc->desc_node);
 602		at_xdmac_init_used_desc(desc);
 603	}
 604
 605	return desc;
 606}
 607
 608static void at_xdmac_queue_desc(struct dma_chan *chan,
 609				struct at_xdmac_desc *prev,
 610				struct at_xdmac_desc *desc)
 611{
 612	if (!prev || !desc)
 613		return;
 614
 615	prev->lld.mbr_nda = desc->tx_dma_desc.phys;
 616	prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE;
 617
 618	dev_dbg(chan2dev(chan),	"%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
 619		__func__, prev, &prev->lld.mbr_nda);
 620}
 621
 622static inline void at_xdmac_increment_block_count(struct dma_chan *chan,
 623						  struct at_xdmac_desc *desc)
 624{
 625	if (!desc)
 626		return;
 627
 628	desc->lld.mbr_bc++;
 629
 630	dev_dbg(chan2dev(chan),
 631		"%s: incrementing the block count of the desc 0x%p\n",
 632		__func__, desc);
 633}
 634
 635static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
 636				       struct of_dma *of_dma)
 637{
 638	struct at_xdmac		*atxdmac = of_dma->of_dma_data;
 639	struct at_xdmac_chan	*atchan;
 640	struct dma_chan		*chan;
 641	struct device		*dev = atxdmac->dma.dev;
 642
 643	if (dma_spec->args_count != 1) {
 644		dev_err(dev, "dma phandler args: bad number of args\n");
 645		return NULL;
 646	}
 647
 648	chan = dma_get_any_slave_channel(&atxdmac->dma);
 649	if (!chan) {
 650		dev_err(dev, "can't get a dma channel\n");
 651		return NULL;
 652	}
 653
 654	atchan = to_at_xdmac_chan(chan);
 655	atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]);
 656	atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]);
 657	atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]);
 658	dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n",
 659		 atchan->memif, atchan->perif, atchan->perid);
 660
 661	return chan;
 662}
 663
 664static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
 665				      enum dma_transfer_direction direction)
 666{
 667	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 668	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
 669	int			csize, dwidth;
 670
 671	if (direction == DMA_DEV_TO_MEM) {
 672		atchan->cfg =
 673			AT91_XDMAC_DT_PERID(atchan->perid)
 674			| AT_XDMAC_CC_DAM_INCREMENTED_AM
 675			| AT_XDMAC_CC_SAM_FIXED_AM
 
 
 676			| AT_XDMAC_CC_SWREQ_HWR_CONNECTED
 677			| AT_XDMAC_CC_DSYNC_PER2MEM
 678			| AT_XDMAC_CC_MBSIZE_SIXTEEN
 679			| AT_XDMAC_CC_TYPE_PER_TRAN;
 680		if (atxdmac->layout->sdif)
 681			atchan->cfg |= AT_XDMAC_CC_DIF(atchan->memif) |
 682				       AT_XDMAC_CC_SIF(atchan->perif);
 683
 684		csize = ffs(atchan->sconfig.src_maxburst) - 1;
 685		if (csize < 0) {
 686			dev_err(chan2dev(chan), "invalid src maxburst value\n");
 687			return -EINVAL;
 688		}
 689		atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
 690		dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
 691		if (dwidth < 0) {
 692			dev_err(chan2dev(chan), "invalid src addr width value\n");
 693			return -EINVAL;
 694		}
 695		atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
 696	} else if (direction == DMA_MEM_TO_DEV) {
 697		atchan->cfg =
 698			AT91_XDMAC_DT_PERID(atchan->perid)
 699			| AT_XDMAC_CC_DAM_FIXED_AM
 700			| AT_XDMAC_CC_SAM_INCREMENTED_AM
 
 
 701			| AT_XDMAC_CC_SWREQ_HWR_CONNECTED
 702			| AT_XDMAC_CC_DSYNC_MEM2PER
 703			| AT_XDMAC_CC_MBSIZE_SIXTEEN
 704			| AT_XDMAC_CC_TYPE_PER_TRAN;
 705		if (atxdmac->layout->sdif)
 706			atchan->cfg |= AT_XDMAC_CC_DIF(atchan->perif) |
 707				       AT_XDMAC_CC_SIF(atchan->memif);
 708
 709		csize = ffs(atchan->sconfig.dst_maxburst) - 1;
 710		if (csize < 0) {
 711			dev_err(chan2dev(chan), "invalid src maxburst value\n");
 712			return -EINVAL;
 713		}
 714		atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
 715		dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
 716		if (dwidth < 0) {
 717			dev_err(chan2dev(chan), "invalid dst addr width value\n");
 718			return -EINVAL;
 719		}
 720		atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
 721	}
 722
 723	dev_dbg(chan2dev(chan),	"%s: cfg=0x%08x\n", __func__, atchan->cfg);
 724
 725	return 0;
 726}
 727
 728/*
 729 * Only check that maxburst and addr width values are supported by
 730 * the controller but not that the configuration is good to perform the
 731 * transfer since we don't know the direction at this stage.
 732 */
 733static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
 734{
 735	if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
 736	    || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
 737		return -EINVAL;
 738
 739	if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
 740	    || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
 741		return -EINVAL;
 742
 743	return 0;
 744}
 745
 746static int at_xdmac_set_slave_config(struct dma_chan *chan,
 747				      struct dma_slave_config *sconfig)
 748{
 749	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 750
 751	if (at_xdmac_check_slave_config(sconfig)) {
 752		dev_err(chan2dev(chan), "invalid slave configuration\n");
 753		return -EINVAL;
 754	}
 755
 756	memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
 757
 758	return 0;
 759}
 760
 761static struct dma_async_tx_descriptor *
 762at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 763		       unsigned int sg_len, enum dma_transfer_direction direction,
 764		       unsigned long flags, void *context)
 765{
 766	struct at_xdmac_chan		*atchan = to_at_xdmac_chan(chan);
 767	struct at_xdmac_desc		*first = NULL, *prev = NULL;
 768	struct scatterlist		*sg;
 769	int				i;
 770	unsigned int			xfer_size = 0;
 771	unsigned long			irqflags;
 772	struct dma_async_tx_descriptor	*ret = NULL;
 773
 774	if (!sgl)
 775		return NULL;
 776
 777	if (!is_slave_direction(direction)) {
 778		dev_err(chan2dev(chan), "invalid DMA direction\n");
 779		return NULL;
 780	}
 781
 782	dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n",
 783		 __func__, sg_len,
 784		 direction == DMA_MEM_TO_DEV ? "to device" : "from device",
 785		 flags);
 786
 787	/* Protect dma_sconfig field that can be modified by set_slave_conf. */
 788	spin_lock_irqsave(&atchan->lock, irqflags);
 789
 790	if (at_xdmac_compute_chan_conf(chan, direction))
 791		goto spin_unlock;
 792
 793	/* Prepare descriptors. */
 794	for_each_sg(sgl, sg, sg_len, i) {
 795		struct at_xdmac_desc	*desc = NULL;
 796		u32			len, mem, dwidth, fixed_dwidth;
 797
 798		len = sg_dma_len(sg);
 799		mem = sg_dma_address(sg);
 800		if (unlikely(!len)) {
 801			dev_err(chan2dev(chan), "sg data length is zero\n");
 802			goto spin_unlock;
 803		}
 804		dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n",
 805			 __func__, i, len, mem);
 806
 807		desc = at_xdmac_get_desc(atchan);
 808		if (!desc) {
 809			dev_err(chan2dev(chan), "can't get descriptor\n");
 810			if (first)
 811				list_splice_tail_init(&first->descs_list,
 812						      &atchan->free_descs_list);
 813			goto spin_unlock;
 814		}
 815
 816		/* Linked list descriptor setup. */
 817		if (direction == DMA_DEV_TO_MEM) {
 818			desc->lld.mbr_sa = atchan->sconfig.src_addr;
 819			desc->lld.mbr_da = mem;
 820		} else {
 821			desc->lld.mbr_sa = mem;
 822			desc->lld.mbr_da = atchan->sconfig.dst_addr;
 823		}
 824		dwidth = at_xdmac_get_dwidth(atchan->cfg);
 825		fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
 826			       ? dwidth
 827			       : AT_XDMAC_CC_DWIDTH_BYTE;
 828		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2			/* next descriptor view */
 829			| AT_XDMAC_MBR_UBC_NDEN					/* next descriptor dst parameter update */
 830			| AT_XDMAC_MBR_UBC_NSEN					/* next descriptor src parameter update */
 831			| (len >> fixed_dwidth);				/* microblock length */
 832		desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) |
 833				    AT_XDMAC_CC_DWIDTH(fixed_dwidth);
 834		dev_dbg(chan2dev(chan),
 835			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
 836			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
 837
 838		/* Chain lld. */
 839		if (prev)
 840			at_xdmac_queue_desc(chan, prev, desc);
 841
 842		prev = desc;
 843		if (!first)
 844			first = desc;
 845
 846		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
 847			 __func__, desc, first);
 848		list_add_tail(&desc->desc_node, &first->descs_list);
 849		xfer_size += len;
 850	}
 851
 852
 853	first->tx_dma_desc.flags = flags;
 854	first->xfer_size = xfer_size;
 855	first->direction = direction;
 856	ret = &first->tx_dma_desc;
 857
 858spin_unlock:
 859	spin_unlock_irqrestore(&atchan->lock, irqflags);
 860	return ret;
 861}
 862
 863static struct dma_async_tx_descriptor *
 864at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
 865			 size_t buf_len, size_t period_len,
 866			 enum dma_transfer_direction direction,
 867			 unsigned long flags)
 868{
 869	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 870	struct at_xdmac_desc	*first = NULL, *prev = NULL;
 871	unsigned int		periods = buf_len / period_len;
 872	int			i;
 873	unsigned long		irqflags;
 874
 875	dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n",
 876		__func__, &buf_addr, buf_len, period_len,
 877		direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags);
 878
 879	if (!is_slave_direction(direction)) {
 880		dev_err(chan2dev(chan), "invalid DMA direction\n");
 881		return NULL;
 882	}
 883
 884	if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
 885		dev_err(chan2dev(chan), "channel currently used\n");
 886		return NULL;
 887	}
 888
 889	if (at_xdmac_compute_chan_conf(chan, direction))
 890		return NULL;
 891
 892	for (i = 0; i < periods; i++) {
 893		struct at_xdmac_desc	*desc = NULL;
 894
 895		spin_lock_irqsave(&atchan->lock, irqflags);
 896		desc = at_xdmac_get_desc(atchan);
 897		if (!desc) {
 898			dev_err(chan2dev(chan), "can't get descriptor\n");
 899			if (first)
 900				list_splice_tail_init(&first->descs_list,
 901						      &atchan->free_descs_list);
 902			spin_unlock_irqrestore(&atchan->lock, irqflags);
 903			return NULL;
 904		}
 905		spin_unlock_irqrestore(&atchan->lock, irqflags);
 906		dev_dbg(chan2dev(chan),
 907			"%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
 908			__func__, desc, &desc->tx_dma_desc.phys);
 909
 910		if (direction == DMA_DEV_TO_MEM) {
 911			desc->lld.mbr_sa = atchan->sconfig.src_addr;
 912			desc->lld.mbr_da = buf_addr + i * period_len;
 913		} else {
 914			desc->lld.mbr_sa = buf_addr + i * period_len;
 915			desc->lld.mbr_da = atchan->sconfig.dst_addr;
 916		}
 917		desc->lld.mbr_cfg = atchan->cfg;
 918		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
 919			| AT_XDMAC_MBR_UBC_NDEN
 920			| AT_XDMAC_MBR_UBC_NSEN
 921			| period_len >> at_xdmac_get_dwidth(desc->lld.mbr_cfg);
 922
 923		dev_dbg(chan2dev(chan),
 924			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
 925			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
 926
 927		/* Chain lld. */
 928		if (prev)
 929			at_xdmac_queue_desc(chan, prev, desc);
 930
 931		prev = desc;
 932		if (!first)
 933			first = desc;
 934
 935		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
 936			 __func__, desc, first);
 937		list_add_tail(&desc->desc_node, &first->descs_list);
 938	}
 939
 940	at_xdmac_queue_desc(chan, prev, first);
 941	first->tx_dma_desc.flags = flags;
 942	first->xfer_size = buf_len;
 943	first->direction = direction;
 944
 945	return &first->tx_dma_desc;
 946}
 947
 948static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr)
 949{
 950	u32 width;
 951
 952	/*
 953	 * Check address alignment to select the greater data width we
 954	 * can use.
 955	 *
 956	 * Some XDMAC implementations don't provide dword transfer, in
 957	 * this case selecting dword has the same behavior as
 958	 * selecting word transfers.
 959	 */
 960	if (!(addr & 7)) {
 961		width = AT_XDMAC_CC_DWIDTH_DWORD;
 962		dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__);
 963	} else if (!(addr & 3)) {
 964		width = AT_XDMAC_CC_DWIDTH_WORD;
 965		dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__);
 966	} else if (!(addr & 1)) {
 967		width = AT_XDMAC_CC_DWIDTH_HALFWORD;
 968		dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__);
 969	} else {
 970		width = AT_XDMAC_CC_DWIDTH_BYTE;
 971		dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__);
 972	}
 973
 974	return width;
 975}
 976
 977static struct at_xdmac_desc *
 978at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
 979				struct at_xdmac_chan *atchan,
 980				struct at_xdmac_desc *prev,
 981				dma_addr_t src, dma_addr_t dst,
 982				struct dma_interleaved_template *xt,
 983				struct data_chunk *chunk)
 984{
 985	struct at_xdmac_desc	*desc;
 986	u32			dwidth;
 987	unsigned long		flags;
 988	size_t			ublen;
 989	/*
 990	 * WARNING: The channel configuration is set here since there is no
 991	 * dmaengine_slave_config call in this case. Moreover we don't know the
 992	 * direction, it involves we can't dynamically set the source and dest
 993	 * interface so we have to use the same one. Only interface 0 allows EBI
 994	 * access. Hopefully we can access DDR through both ports (at least on
 995	 * SAMA5D4x), so we can use the same interface for source and dest,
 996	 * that solves the fact we don't know the direction.
 997	 * ERRATA: Even if useless for memory transfers, the PERID has to not
 998	 * match the one of another channel. If not, it could lead to spurious
 999	 * flag status.
1000	 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1001	 * Thus, no need to have the SIF/DIF interfaces here.
1002	 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1003	 * zero.
1004	 */
1005	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
 
 
1006					| AT_XDMAC_CC_MBSIZE_SIXTEEN
1007					| AT_XDMAC_CC_TYPE_MEM_TRAN;
1008
1009	dwidth = at_xdmac_align_width(chan, src | dst | chunk->size);
1010	if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1011		dev_dbg(chan2dev(chan),
1012			"%s: chunk too big (%zu, max size %lu)...\n",
1013			__func__, chunk->size,
1014			AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth);
1015		return NULL;
1016	}
1017
1018	if (prev)
1019		dev_dbg(chan2dev(chan),
1020			"Adding items at the end of desc 0x%p\n", prev);
1021
1022	if (xt->src_inc) {
1023		if (xt->src_sgl)
1024			chan_cc |=  AT_XDMAC_CC_SAM_UBS_AM;
1025		else
1026			chan_cc |=  AT_XDMAC_CC_SAM_INCREMENTED_AM;
1027	}
1028
1029	if (xt->dst_inc) {
1030		if (xt->dst_sgl)
1031			chan_cc |=  AT_XDMAC_CC_DAM_UBS_AM;
1032		else
1033			chan_cc |=  AT_XDMAC_CC_DAM_INCREMENTED_AM;
1034	}
1035
1036	spin_lock_irqsave(&atchan->lock, flags);
1037	desc = at_xdmac_get_desc(atchan);
1038	spin_unlock_irqrestore(&atchan->lock, flags);
1039	if (!desc) {
1040		dev_err(chan2dev(chan), "can't get descriptor\n");
1041		return NULL;
1042	}
1043
1044	chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1045
1046	ublen = chunk->size >> dwidth;
1047
1048	desc->lld.mbr_sa = src;
1049	desc->lld.mbr_da = dst;
1050	desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
1051	desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
1052
1053	desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1054		| AT_XDMAC_MBR_UBC_NDEN
1055		| AT_XDMAC_MBR_UBC_NSEN
1056		| ublen;
1057	desc->lld.mbr_cfg = chan_cc;
1058
1059	dev_dbg(chan2dev(chan),
1060		"%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1061		__func__, &desc->lld.mbr_sa, &desc->lld.mbr_da,
1062		desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1063
1064	/* Chain lld. */
1065	if (prev)
1066		at_xdmac_queue_desc(chan, prev, desc);
1067
1068	return desc;
1069}
1070
1071static struct dma_async_tx_descriptor *
1072at_xdmac_prep_interleaved(struct dma_chan *chan,
1073			  struct dma_interleaved_template *xt,
1074			  unsigned long flags)
1075{
1076	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1077	struct at_xdmac_desc	*prev = NULL, *first = NULL;
1078	dma_addr_t		dst_addr, src_addr;
1079	size_t			src_skip = 0, dst_skip = 0, len = 0;
1080	struct data_chunk	*chunk;
1081	int			i;
1082
1083	if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
1084		return NULL;
1085
1086	/*
1087	 * TODO: Handle the case where we have to repeat a chain of
1088	 * descriptors...
1089	 */
1090	if ((xt->numf > 1) && (xt->frame_size > 1))
1091		return NULL;
1092
1093	dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%zu, frame_size=%zu, flags=0x%lx\n",
1094		__func__, &xt->src_start, &xt->dst_start,	xt->numf,
1095		xt->frame_size, flags);
1096
1097	src_addr = xt->src_start;
1098	dst_addr = xt->dst_start;
1099
1100	if (xt->numf > 1) {
1101		first = at_xdmac_interleaved_queue_desc(chan, atchan,
1102							NULL,
1103							src_addr, dst_addr,
1104							xt, xt->sgl);
1105		if (!first)
1106			return NULL;
1107
1108		/* Length of the block is (BLEN+1) microblocks. */
1109		for (i = 0; i < xt->numf - 1; i++)
1110			at_xdmac_increment_block_count(chan, first);
1111
1112		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1113			__func__, first, first);
1114		list_add_tail(&first->desc_node, &first->descs_list);
1115	} else {
1116		for (i = 0; i < xt->frame_size; i++) {
1117			size_t src_icg = 0, dst_icg = 0;
1118			struct at_xdmac_desc *desc;
1119
1120			chunk = xt->sgl + i;
1121
1122			dst_icg = dmaengine_get_dst_icg(xt, chunk);
1123			src_icg = dmaengine_get_src_icg(xt, chunk);
1124
1125			src_skip = chunk->size + src_icg;
1126			dst_skip = chunk->size + dst_icg;
1127
1128			dev_dbg(chan2dev(chan),
1129				"%s: chunk size=%zu, src icg=%zu, dst icg=%zu\n",
1130				__func__, chunk->size, src_icg, dst_icg);
1131
1132			desc = at_xdmac_interleaved_queue_desc(chan, atchan,
1133							       prev,
1134							       src_addr, dst_addr,
1135							       xt, chunk);
1136			if (!desc) {
1137				if (first)
1138					list_splice_tail_init(&first->descs_list,
1139							      &atchan->free_descs_list);
1140				return NULL;
1141			}
1142
1143			if (!first)
1144				first = desc;
1145
1146			dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1147				__func__, desc, first);
1148			list_add_tail(&desc->desc_node, &first->descs_list);
1149
1150			if (xt->src_sgl)
1151				src_addr += src_skip;
1152
1153			if (xt->dst_sgl)
1154				dst_addr += dst_skip;
1155
1156			len += chunk->size;
1157			prev = desc;
1158		}
1159	}
1160
1161	first->tx_dma_desc.cookie = -EBUSY;
1162	first->tx_dma_desc.flags = flags;
1163	first->xfer_size = len;
1164
1165	return &first->tx_dma_desc;
1166}
1167
1168static struct dma_async_tx_descriptor *
1169at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1170			 size_t len, unsigned long flags)
1171{
1172	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1173	struct at_xdmac_desc	*first = NULL, *prev = NULL;
1174	size_t			remaining_size = len, xfer_size = 0, ublen;
1175	dma_addr_t		src_addr = src, dst_addr = dest;
1176	u32			dwidth;
1177	/*
1178	 * WARNING: We don't know the direction, it involves we can't
1179	 * dynamically set the source and dest interface so we have to use the
1180	 * same one. Only interface 0 allows EBI access. Hopefully we can
1181	 * access DDR through both ports (at least on SAMA5D4x), so we can use
1182	 * the same interface for source and dest, that solves the fact we
1183	 * don't know the direction.
1184	 * ERRATA: Even if useless for memory transfers, the PERID has to not
1185	 * match the one of another channel. If not, it could lead to spurious
1186	 * flag status.
1187	 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1188	 * Thus, no need to have the SIF/DIF interfaces here.
1189	 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1190	 * zero.
1191	 */
1192	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
1193					| AT_XDMAC_CC_DAM_INCREMENTED_AM
1194					| AT_XDMAC_CC_SAM_INCREMENTED_AM
 
 
1195					| AT_XDMAC_CC_MBSIZE_SIXTEEN
1196					| AT_XDMAC_CC_TYPE_MEM_TRAN;
1197	unsigned long		irqflags;
1198
1199	dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n",
1200		__func__, &src, &dest, len, flags);
1201
1202	if (unlikely(!len))
1203		return NULL;
1204
1205	dwidth = at_xdmac_align_width(chan, src_addr | dst_addr);
1206
1207	/* Prepare descriptors. */
1208	while (remaining_size) {
1209		struct at_xdmac_desc	*desc = NULL;
1210
1211		dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size);
1212
1213		spin_lock_irqsave(&atchan->lock, irqflags);
1214		desc = at_xdmac_get_desc(atchan);
1215		spin_unlock_irqrestore(&atchan->lock, irqflags);
1216		if (!desc) {
1217			dev_err(chan2dev(chan), "can't get descriptor\n");
1218			if (first)
1219				list_splice_tail_init(&first->descs_list,
1220						      &atchan->free_descs_list);
1221			return NULL;
1222		}
1223
1224		/* Update src and dest addresses. */
1225		src_addr += xfer_size;
1226		dst_addr += xfer_size;
1227
1228		if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)
1229			xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth;
1230		else
1231			xfer_size = remaining_size;
1232
1233		dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size);
1234
1235		/* Check remaining length and change data width if needed. */
1236		dwidth = at_xdmac_align_width(chan,
1237					      src_addr | dst_addr | xfer_size);
1238		chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK;
1239		chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1240
1241		ublen = xfer_size >> dwidth;
1242		remaining_size -= xfer_size;
1243
1244		desc->lld.mbr_sa = src_addr;
1245		desc->lld.mbr_da = dst_addr;
1246		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2
1247			| AT_XDMAC_MBR_UBC_NDEN
1248			| AT_XDMAC_MBR_UBC_NSEN
1249			| ublen;
1250		desc->lld.mbr_cfg = chan_cc;
1251
1252		dev_dbg(chan2dev(chan),
1253			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1254			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1255
1256		/* Chain lld. */
1257		if (prev)
1258			at_xdmac_queue_desc(chan, prev, desc);
1259
1260		prev = desc;
1261		if (!first)
1262			first = desc;
1263
1264		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1265			 __func__, desc, first);
1266		list_add_tail(&desc->desc_node, &first->descs_list);
1267	}
1268
1269	first->tx_dma_desc.flags = flags;
1270	first->xfer_size = len;
1271
1272	return &first->tx_dma_desc;
1273}
1274
1275static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
1276							 struct at_xdmac_chan *atchan,
1277							 dma_addr_t dst_addr,
1278							 size_t len,
1279							 int value)
1280{
1281	struct at_xdmac_desc	*desc;
1282	unsigned long		flags;
1283	size_t			ublen;
1284	u32			dwidth;
1285	char			pattern;
1286	/*
1287	 * WARNING: The channel configuration is set here since there is no
1288	 * dmaengine_slave_config call in this case. Moreover we don't know the
1289	 * direction, it involves we can't dynamically set the source and dest
1290	 * interface so we have to use the same one. Only interface 0 allows EBI
1291	 * access. Hopefully we can access DDR through both ports (at least on
1292	 * SAMA5D4x), so we can use the same interface for source and dest,
1293	 * that solves the fact we don't know the direction.
1294	 * ERRATA: Even if useless for memory transfers, the PERID has to not
1295	 * match the one of another channel. If not, it could lead to spurious
1296	 * flag status.
1297	 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1298	 * Thus, no need to have the SIF/DIF interfaces here.
1299	 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1300	 * zero.
1301	 */
1302	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
1303					| AT_XDMAC_CC_DAM_UBS_AM
1304					| AT_XDMAC_CC_SAM_INCREMENTED_AM
 
 
1305					| AT_XDMAC_CC_MBSIZE_SIXTEEN
1306					| AT_XDMAC_CC_MEMSET_HW_MODE
1307					| AT_XDMAC_CC_TYPE_MEM_TRAN;
1308
1309	dwidth = at_xdmac_align_width(chan, dst_addr);
1310
1311	if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1312		dev_err(chan2dev(chan),
1313			"%s: Transfer too large, aborting...\n",
1314			__func__);
1315		return NULL;
1316	}
1317
1318	spin_lock_irqsave(&atchan->lock, flags);
1319	desc = at_xdmac_get_desc(atchan);
1320	spin_unlock_irqrestore(&atchan->lock, flags);
1321	if (!desc) {
1322		dev_err(chan2dev(chan), "can't get descriptor\n");
1323		return NULL;
1324	}
1325
1326	chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1327
1328	/* Only the first byte of value is to be used according to dmaengine */
1329	pattern = (char)value;
1330
1331	ublen = len >> dwidth;
1332
1333	desc->lld.mbr_da = dst_addr;
1334	desc->lld.mbr_ds = (pattern << 24) |
1335			   (pattern << 16) |
1336			   (pattern << 8) |
1337			   pattern;
1338	desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1339		| AT_XDMAC_MBR_UBC_NDEN
1340		| AT_XDMAC_MBR_UBC_NSEN
1341		| ublen;
1342	desc->lld.mbr_cfg = chan_cc;
1343
1344	dev_dbg(chan2dev(chan),
1345		"%s: lld: mbr_da=%pad, mbr_ds=0x%08x, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1346		__func__, &desc->lld.mbr_da, desc->lld.mbr_ds, desc->lld.mbr_ubc,
1347		desc->lld.mbr_cfg);
1348
1349	return desc;
1350}
1351
1352static struct dma_async_tx_descriptor *
1353at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
1354			 size_t len, unsigned long flags)
1355{
1356	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1357	struct at_xdmac_desc	*desc;
1358
1359	dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%zu, pattern=0x%x, flags=0x%lx\n",
1360		__func__, &dest, len, value, flags);
1361
1362	if (unlikely(!len))
1363		return NULL;
1364
1365	desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value);
1366	list_add_tail(&desc->desc_node, &desc->descs_list);
1367
1368	desc->tx_dma_desc.cookie = -EBUSY;
1369	desc->tx_dma_desc.flags = flags;
1370	desc->xfer_size = len;
1371
1372	return &desc->tx_dma_desc;
1373}
1374
1375static struct dma_async_tx_descriptor *
1376at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
1377			    unsigned int sg_len, int value,
1378			    unsigned long flags)
1379{
1380	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1381	struct at_xdmac_desc	*desc, *pdesc = NULL,
1382				*ppdesc = NULL, *first = NULL;
1383	struct scatterlist	*sg, *psg = NULL, *ppsg = NULL;
1384	size_t			stride = 0, pstride = 0, len = 0;
1385	int			i;
1386
1387	if (!sgl)
1388		return NULL;
1389
1390	dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n",
1391		__func__, sg_len, value, flags);
1392
1393	/* Prepare descriptors. */
1394	for_each_sg(sgl, sg, sg_len, i) {
1395		dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
1396			__func__, &sg_dma_address(sg), sg_dma_len(sg),
1397			value, flags);
1398		desc = at_xdmac_memset_create_desc(chan, atchan,
1399						   sg_dma_address(sg),
1400						   sg_dma_len(sg),
1401						   value);
1402		if (!desc && first)
1403			list_splice_tail_init(&first->descs_list,
1404					      &atchan->free_descs_list);
1405
1406		if (!first)
1407			first = desc;
1408
1409		/* Update our strides */
1410		pstride = stride;
1411		if (psg)
1412			stride = sg_dma_address(sg) -
1413				(sg_dma_address(psg) + sg_dma_len(psg));
1414
1415		/*
1416		 * The scatterlist API gives us only the address and
1417		 * length of each elements.
1418		 *
1419		 * Unfortunately, we don't have the stride, which we
1420		 * will need to compute.
1421		 *
1422		 * That make us end up in a situation like this one:
1423		 *    len    stride    len    stride    len
1424		 * +-------+        +-------+        +-------+
1425		 * |  N-2  |        |  N-1  |        |   N   |
1426		 * +-------+        +-------+        +-------+
1427		 *
1428		 * We need all these three elements (N-2, N-1 and N)
1429		 * to actually take the decision on whether we need to
1430		 * queue N-1 or reuse N-2.
1431		 *
1432		 * We will only consider N if it is the last element.
1433		 */
1434		if (ppdesc && pdesc) {
1435			if ((stride == pstride) &&
1436			    (sg_dma_len(ppsg) == sg_dma_len(psg))) {
1437				dev_dbg(chan2dev(chan),
1438					"%s: desc 0x%p can be merged with desc 0x%p\n",
1439					__func__, pdesc, ppdesc);
1440
1441				/*
1442				 * Increment the block count of the
1443				 * N-2 descriptor
1444				 */
1445				at_xdmac_increment_block_count(chan, ppdesc);
1446				ppdesc->lld.mbr_dus = stride;
1447
1448				/*
1449				 * Put back the N-1 descriptor in the
1450				 * free descriptor list
1451				 */
1452				list_add_tail(&pdesc->desc_node,
1453					      &atchan->free_descs_list);
1454
1455				/*
1456				 * Make our N-1 descriptor pointer
1457				 * point to the N-2 since they were
1458				 * actually merged.
1459				 */
1460				pdesc = ppdesc;
1461
1462			/*
1463			 * Rule out the case where we don't have
1464			 * pstride computed yet (our second sg
1465			 * element)
1466			 *
1467			 * We also want to catch the case where there
1468			 * would be a negative stride,
1469			 */
1470			} else if (pstride ||
1471				   sg_dma_address(sg) < sg_dma_address(psg)) {
1472				/*
1473				 * Queue the N-1 descriptor after the
1474				 * N-2
1475				 */
1476				at_xdmac_queue_desc(chan, ppdesc, pdesc);
1477
1478				/*
1479				 * Add the N-1 descriptor to the list
1480				 * of the descriptors used for this
1481				 * transfer
1482				 */
1483				list_add_tail(&desc->desc_node,
1484					      &first->descs_list);
1485				dev_dbg(chan2dev(chan),
1486					"%s: add desc 0x%p to descs_list 0x%p\n",
1487					__func__, desc, first);
1488			}
1489		}
1490
1491		/*
1492		 * If we are the last element, just see if we have the
1493		 * same size than the previous element.
1494		 *
1495		 * If so, we can merge it with the previous descriptor
1496		 * since we don't care about the stride anymore.
1497		 */
1498		if ((i == (sg_len - 1)) &&
1499		    sg_dma_len(psg) == sg_dma_len(sg)) {
1500			dev_dbg(chan2dev(chan),
1501				"%s: desc 0x%p can be merged with desc 0x%p\n",
1502				__func__, desc, pdesc);
1503
1504			/*
1505			 * Increment the block count of the N-1
1506			 * descriptor
1507			 */
1508			at_xdmac_increment_block_count(chan, pdesc);
1509			pdesc->lld.mbr_dus = stride;
1510
1511			/*
1512			 * Put back the N descriptor in the free
1513			 * descriptor list
1514			 */
1515			list_add_tail(&desc->desc_node,
1516				      &atchan->free_descs_list);
1517		}
1518
1519		/* Update our descriptors */
1520		ppdesc = pdesc;
1521		pdesc = desc;
1522
1523		/* Update our scatter pointers */
1524		ppsg = psg;
1525		psg = sg;
1526
1527		len += sg_dma_len(sg);
1528	}
1529
1530	first->tx_dma_desc.cookie = -EBUSY;
1531	first->tx_dma_desc.flags = flags;
1532	first->xfer_size = len;
1533
1534	return &first->tx_dma_desc;
1535}
1536
1537static enum dma_status
1538at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1539		   struct dma_tx_state *txstate)
1540{
1541	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1542	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1543	struct at_xdmac_desc	*desc, *_desc, *iter;
1544	struct list_head	*descs_list;
1545	enum dma_status		ret;
1546	int			residue, retry, pm_status;
1547	u32			cur_nda, check_nda, cur_ubc, mask, value;
1548	u8			dwidth = 0;
1549	unsigned long		flags;
1550	bool			initd;
1551
1552	ret = dma_cookie_status(chan, cookie, txstate);
1553	if (ret == DMA_COMPLETE || !txstate)
1554		return ret;
1555
1556	pm_status = pm_runtime_resume_and_get(atxdmac->dev);
1557	if (pm_status < 0)
1558		return DMA_ERROR;
1559
1560	spin_lock_irqsave(&atchan->lock, flags);
1561
1562	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
1563
1564	/*
1565	 * If the transfer has not been started yet, don't need to compute the
1566	 * residue, it's the transfer length.
1567	 */
1568	if (!desc->active_xfer) {
1569		dma_set_residue(txstate, desc->xfer_size);
1570		goto spin_unlock;
1571	}
1572
1573	residue = desc->xfer_size;
1574	/*
1575	 * Flush FIFO: only relevant when the transfer is source peripheral
1576	 * synchronized. Flush is needed before reading CUBC because data in
1577	 * the FIFO are not reported by CUBC. Reporting a residue of the
1578	 * transfer length while we have data in FIFO can cause issue.
1579	 * Usecase: atmel USART has a timeout which means I have received
1580	 * characters but there is no more character received for a while. On
1581	 * timeout, it requests the residue. If the data are in the DMA FIFO,
1582	 * we will return a residue of the transfer length. It means no data
1583	 * received. If an application is waiting for these data, it will hang
1584	 * since we won't have another USART timeout without receiving new
1585	 * data.
1586	 */
1587	mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC;
1588	value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM;
1589	if ((desc->lld.mbr_cfg & mask) == value) {
1590		at_xdmac_write(atxdmac, atxdmac->layout->gswf, atchan->mask);
1591		while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1592			cpu_relax();
1593	}
1594
1595	/*
1596	 * The easiest way to compute the residue should be to pause the DMA
1597	 * but doing this can lead to miss some data as some devices don't
1598	 * have FIFO.
1599	 * We need to read several registers because:
1600	 * - DMA is running therefore a descriptor change is possible while
1601	 * reading these registers
1602	 * - When the block transfer is done, the value of the CUBC register
1603	 * is set to its initial value until the fetch of the next descriptor.
1604	 * This value will corrupt the residue calculation so we have to skip
1605	 * it.
1606	 *
1607	 * INITD --------                    ------------
1608	 *              |____________________|
1609	 *       _______________________  _______________
1610	 * NDA       @desc2             \/   @desc3
1611	 *       _______________________/\_______________
1612	 *       __________  ___________  _______________
1613	 * CUBC       0    \/ MAX desc1 \/  MAX desc2
1614	 *       __________/\___________/\_______________
1615	 *
1616	 * Since descriptors are aligned on 64 bits, we can assume that
1617	 * the update of NDA and CUBC is atomic.
1618	 * Memory barriers are used to ensure the read order of the registers.
1619	 * A max number of retries is set because unlikely it could never ends.
 
1620	 */
 
 
 
1621	for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
1622		check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1623		rmb();
1624		cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
1625		rmb();
1626		initd = !!(at_xdmac_chan_read(atchan, AT_XDMAC_CC) & AT_XDMAC_CC_INITD);
1627		rmb();
1628		cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1629		rmb();
 
1630
1631		if ((check_nda == cur_nda) && initd)
1632			break;
 
 
 
 
1633	}
1634
1635	if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
1636		ret = DMA_ERROR;
1637		goto spin_unlock;
1638	}
1639
1640	/*
1641	 * Flush FIFO: only relevant when the transfer is source peripheral
1642	 * synchronized. Another flush is needed here because CUBC is updated
1643	 * when the controller sends the data write command. It can lead to
1644	 * report data that are not written in the memory or the device. The
1645	 * FIFO flush ensures that data are really written.
1646	 */
1647	if ((desc->lld.mbr_cfg & mask) == value) {
1648		at_xdmac_write(atxdmac, atxdmac->layout->gswf, atchan->mask);
1649		while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1650			cpu_relax();
1651	}
1652
1653	/*
1654	 * Remove size of all microblocks already transferred and the current
1655	 * one. Then add the remaining size to transfer of the current
1656	 * microblock.
1657	 */
1658	descs_list = &desc->descs_list;
1659	list_for_each_entry_safe(iter, _desc, descs_list, desc_node) {
1660		dwidth = at_xdmac_get_dwidth(iter->lld.mbr_cfg);
1661		residue -= (iter->lld.mbr_ubc & 0xffffff) << dwidth;
1662		if ((iter->lld.mbr_nda & 0xfffffffc) == cur_nda) {
1663			desc = iter;
1664			break;
1665		}
1666	}
1667	residue += cur_ubc << dwidth;
1668
1669	dma_set_residue(txstate, residue);
1670
1671	dev_dbg(chan2dev(chan),
1672		 "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n",
1673		 __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
1674
1675spin_unlock:
1676	spin_unlock_irqrestore(&atchan->lock, flags);
1677	pm_runtime_mark_last_busy(atxdmac->dev);
1678	pm_runtime_put_autosuspend(atxdmac->dev);
1679	return ret;
1680}
1681
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1682static void at_xdmac_advance_work(struct at_xdmac_chan *atchan)
1683{
1684	struct at_xdmac_desc	*desc;
 
 
 
1685
1686	/*
1687	 * If channel is enabled, do nothing, advance_work will be triggered
1688	 * after the interruption.
1689	 */
1690	if (at_xdmac_chan_is_enabled(atchan) || list_empty(&atchan->xfers_list))
1691		return;
 
 
 
 
 
 
1692
1693	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,
1694				xfer_node);
1695	dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1696	if (!desc->active_xfer)
1697		at_xdmac_start_xfer(atchan, desc);
1698}
1699
1700static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
1701{
1702	struct at_xdmac_desc		*desc;
1703	struct dma_async_tx_descriptor	*txd;
1704
1705	spin_lock_irq(&atchan->lock);
1706	dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
1707		__func__, atchan->irq_status);
1708	if (list_empty(&atchan->xfers_list)) {
1709		spin_unlock_irq(&atchan->lock);
1710		return;
1711	}
1712	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,
1713				xfer_node);
1714	spin_unlock_irq(&atchan->lock);
1715	txd = &desc->tx_dma_desc;
1716	if (txd->flags & DMA_PREP_INTERRUPT)
1717		dmaengine_desc_get_callback_invoke(txd, NULL);
1718}
1719
1720/* Called with atchan->lock held. */
1721static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
1722{
1723	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1724	struct at_xdmac_desc	*bad_desc;
1725	int			ret;
1726
1727	ret = pm_runtime_resume_and_get(atxdmac->dev);
1728	if (ret < 0)
1729		return;
1730
1731	/*
1732	 * The descriptor currently at the head of the active list is
1733	 * broken. Since we don't have any way to report errors, we'll
1734	 * just have to scream loudly and try to continue with other
1735	 * descriptors queued (if any).
1736	 */
1737	if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
1738		dev_err(chan2dev(&atchan->chan), "read bus error!!!");
1739	if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
1740		dev_err(chan2dev(&atchan->chan), "write bus error!!!");
1741	if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
1742		dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
1743
1744	/* Channel must be disabled first as it's not done automatically */
1745	at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1746	while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1747		cpu_relax();
1748
1749	bad_desc = list_first_entry(&atchan->xfers_list,
1750				    struct at_xdmac_desc,
1751				    xfer_node);
1752
1753	/* Print bad descriptor's details if needed */
1754	dev_dbg(chan2dev(&atchan->chan),
1755		"%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
1756		__func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da,
1757		bad_desc->lld.mbr_ubc);
1758
1759	pm_runtime_mark_last_busy(atxdmac->dev);
1760	pm_runtime_put_autosuspend(atxdmac->dev);
1761
1762	/* Then continue with usual descriptor management */
1763}
1764
1765static void at_xdmac_tasklet(struct tasklet_struct *t)
1766{
1767	struct at_xdmac_chan	*atchan = from_tasklet(atchan, t, tasklet);
1768	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1769	struct at_xdmac_desc	*desc;
1770	struct dma_async_tx_descriptor *txd;
1771	u32			error_mask;
1772
1773	if (at_xdmac_chan_is_cyclic(atchan))
1774		return at_xdmac_handle_cyclic(atchan);
1775
1776	error_mask = AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS |
1777		AT_XDMAC_CIS_ROIS;
1778
1779	spin_lock_irq(&atchan->lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1780
1781	dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
1782		__func__, atchan->irq_status);
1783
1784	if (!(atchan->irq_status & AT_XDMAC_CIS_LIS) &&
1785	    !(atchan->irq_status & error_mask)) {
1786		spin_unlock_irq(&atchan->lock);
1787		return;
1788	}
1789
1790	if (atchan->irq_status & error_mask)
1791		at_xdmac_handle_error(atchan);
1792
1793	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,
1794				xfer_node);
1795	dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1796	if (!desc->active_xfer) {
1797		dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
1798		spin_unlock_irq(&atchan->lock);
1799		return;
1800	}
1801
1802	txd = &desc->tx_dma_desc;
1803	dma_cookie_complete(txd);
1804	/* Remove the transfer from the transfer list. */
1805	list_del(&desc->xfer_node);
1806	spin_unlock_irq(&atchan->lock);
1807
1808	if (txd->flags & DMA_PREP_INTERRUPT)
1809		dmaengine_desc_get_callback_invoke(txd, NULL);
1810
1811	dma_run_dependencies(txd);
1812
1813	spin_lock_irq(&atchan->lock);
1814	/* Move the xfer descriptors into the free descriptors list. */
1815	list_splice_tail_init(&desc->descs_list, &atchan->free_descs_list);
1816	at_xdmac_advance_work(atchan);
1817	spin_unlock_irq(&atchan->lock);
1818
1819	/*
1820	 * Decrement runtime PM ref counter incremented in
1821	 * at_xdmac_start_xfer().
1822	 */
1823	pm_runtime_mark_last_busy(atxdmac->dev);
1824	pm_runtime_put_autosuspend(atxdmac->dev);
1825}
1826
1827static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
1828{
1829	struct at_xdmac		*atxdmac = (struct at_xdmac *)dev_id;
1830	struct at_xdmac_chan	*atchan;
1831	u32			imr, status, pending;
1832	u32			chan_imr, chan_status;
1833	int			i, ret = IRQ_NONE;
1834
1835	do {
1836		imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1837		status = at_xdmac_read(atxdmac, AT_XDMAC_GIS);
1838		pending = status & imr;
1839
1840		dev_vdbg(atxdmac->dma.dev,
1841			 "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n",
1842			 __func__, status, imr, pending);
1843
1844		if (!pending)
1845			break;
1846
1847		/* We have to find which channel has generated the interrupt. */
1848		for (i = 0; i < atxdmac->dma.chancnt; i++) {
1849			if (!((1 << i) & pending))
1850				continue;
1851
1852			atchan = &atxdmac->chan[i];
1853			chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1854			chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
1855			atchan->irq_status = chan_status & chan_imr;
1856			dev_vdbg(atxdmac->dma.dev,
1857				 "%s: chan%d: imr=0x%x, status=0x%x\n",
1858				 __func__, i, chan_imr, chan_status);
1859			dev_vdbg(chan2dev(&atchan->chan),
1860				 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
1861				 __func__,
1862				 at_xdmac_chan_read(atchan, AT_XDMAC_CC),
1863				 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
1864				 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
1865				 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
1866				 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
1867				 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
1868
1869			if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
1870				at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1871
1872			tasklet_schedule(&atchan->tasklet);
1873			ret = IRQ_HANDLED;
1874		}
1875
1876	} while (pending);
1877
1878	return ret;
1879}
1880
1881static void at_xdmac_issue_pending(struct dma_chan *chan)
1882{
1883	struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1884	unsigned long flags;
1885
1886	dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__);
1887
1888	spin_lock_irqsave(&atchan->lock, flags);
1889	at_xdmac_advance_work(atchan);
1890	spin_unlock_irqrestore(&atchan->lock, flags);
1891
1892	return;
1893}
1894
1895static int at_xdmac_device_config(struct dma_chan *chan,
1896				  struct dma_slave_config *config)
1897{
1898	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1899	int ret;
1900	unsigned long		flags;
1901
1902	dev_dbg(chan2dev(chan), "%s\n", __func__);
1903
1904	spin_lock_irqsave(&atchan->lock, flags);
1905	ret = at_xdmac_set_slave_config(chan, config);
1906	spin_unlock_irqrestore(&atchan->lock, flags);
1907
1908	return ret;
1909}
1910
1911static void at_xdmac_device_pause_set(struct at_xdmac *atxdmac,
1912				      struct at_xdmac_chan *atchan)
1913{
1914	at_xdmac_write(atxdmac, atxdmac->layout->grws, atchan->mask);
1915	while (at_xdmac_chan_read(atchan, AT_XDMAC_CC) &
1916	       (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP))
1917		cpu_relax();
1918}
1919
1920static void at_xdmac_device_pause_internal(struct at_xdmac_chan *atchan)
1921{
1922	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1923	unsigned long		flags;
1924
1925	spin_lock_irqsave(&atchan->lock, flags);
1926	set_bit(AT_XDMAC_CHAN_IS_PAUSED_INTERNAL, &atchan->status);
1927	at_xdmac_device_pause_set(atxdmac, atchan);
1928	spin_unlock_irqrestore(&atchan->lock, flags);
1929}
1930
1931static int at_xdmac_device_pause(struct dma_chan *chan)
1932{
1933	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1934	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1935	unsigned long		flags;
1936	int			ret;
1937
1938	dev_dbg(chan2dev(chan), "%s\n", __func__);
1939
1940	if (test_and_set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status))
1941		return 0;
1942
1943	ret = pm_runtime_resume_and_get(atxdmac->dev);
1944	if (ret < 0)
1945		return ret;
1946
1947	spin_lock_irqsave(&atchan->lock, flags);
1948
1949	at_xdmac_device_pause_set(atxdmac, atchan);
1950	/* Decrement runtime PM ref counter for each active descriptor. */
1951	at_xdmac_runtime_suspend_descriptors(atchan);
1952
1953	spin_unlock_irqrestore(&atchan->lock, flags);
1954
1955	pm_runtime_mark_last_busy(atxdmac->dev);
1956	pm_runtime_put_autosuspend(atxdmac->dev);
1957
1958	return 0;
1959}
1960
1961static void at_xdmac_device_resume_internal(struct at_xdmac_chan *atchan)
1962{
1963	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1964	unsigned long		flags;
1965
1966	spin_lock_irqsave(&atchan->lock, flags);
1967	at_xdmac_write(atxdmac, atxdmac->layout->grwr, atchan->mask);
1968	clear_bit(AT_XDMAC_CHAN_IS_PAUSED_INTERNAL, &atchan->status);
1969	spin_unlock_irqrestore(&atchan->lock, flags);
1970}
1971
1972static int at_xdmac_device_resume(struct dma_chan *chan)
1973{
1974	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1975	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1976	unsigned long		flags;
1977	int			ret;
1978
1979	dev_dbg(chan2dev(chan), "%s\n", __func__);
1980
1981	ret = pm_runtime_resume_and_get(atxdmac->dev);
1982	if (ret < 0)
1983		return ret;
1984
1985	spin_lock_irqsave(&atchan->lock, flags);
1986	if (!at_xdmac_chan_is_paused(atchan))
1987		goto unlock;
1988
1989	/* Increment runtime PM ref counter for each active descriptor. */
1990	ret = at_xdmac_runtime_resume_descriptors(atchan);
1991	if (ret < 0)
1992		goto unlock;
1993
1994	at_xdmac_write(atxdmac, atxdmac->layout->grwr, atchan->mask);
1995	clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
1996
1997unlock:
1998	spin_unlock_irqrestore(&atchan->lock, flags);
1999	pm_runtime_mark_last_busy(atxdmac->dev);
2000	pm_runtime_put_autosuspend(atxdmac->dev);
2001
2002	return ret;
2003}
2004
2005static int at_xdmac_device_terminate_all(struct dma_chan *chan)
2006{
2007	struct at_xdmac_desc	*desc, *_desc;
2008	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
2009	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
2010	unsigned long		flags;
2011	int			ret;
2012
2013	dev_dbg(chan2dev(chan), "%s\n", __func__);
2014
2015	ret = pm_runtime_resume_and_get(atxdmac->dev);
2016	if (ret < 0)
2017		return ret;
2018
2019	spin_lock_irqsave(&atchan->lock, flags);
2020	at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
2021	while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
2022		cpu_relax();
2023
2024	/* Cancel all pending transfers. */
2025	list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
2026		list_del(&desc->xfer_node);
2027		list_splice_tail_init(&desc->descs_list,
2028				      &atchan->free_descs_list);
2029		/*
2030		 * We incremented the runtime PM reference count on
2031		 * at_xdmac_start_xfer() for this descriptor. Now it's time
2032		 * to release it.
2033		 */
2034		if (desc->active_xfer) {
2035			pm_runtime_put_autosuspend(atxdmac->dev);
2036			pm_runtime_mark_last_busy(atxdmac->dev);
2037		}
2038	}
2039
2040	clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
2041	clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
2042	spin_unlock_irqrestore(&atchan->lock, flags);
2043
2044	pm_runtime_mark_last_busy(atxdmac->dev);
2045	pm_runtime_put_autosuspend(atxdmac->dev);
2046
2047	return 0;
2048}
2049
2050static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
2051{
2052	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
2053	struct at_xdmac_desc	*desc;
2054	int			i;
 
 
 
2055
2056	if (at_xdmac_chan_is_enabled(atchan)) {
2057		dev_err(chan2dev(chan),
2058			"can't allocate channel resources (channel enabled)\n");
2059		return -EIO;
 
2060	}
2061
2062	if (!list_empty(&atchan->free_descs_list)) {
2063		dev_err(chan2dev(chan),
2064			"can't allocate channel resources (channel not free from a previous use)\n");
2065		return -EIO;
 
2066	}
2067
2068	for (i = 0; i < init_nr_desc_per_channel; i++) {
2069		desc = at_xdmac_alloc_desc(chan, GFP_KERNEL);
2070		if (!desc) {
2071			if (i == 0) {
2072				dev_warn(chan2dev(chan),
2073					 "can't allocate any descriptors\n");
2074				return -EIO;
2075			}
2076			dev_warn(chan2dev(chan),
2077				"only %d descriptors have been allocated\n", i);
2078			break;
2079		}
2080		list_add_tail(&desc->desc_node, &atchan->free_descs_list);
2081	}
2082
2083	dma_cookie_init(chan);
2084
2085	dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
2086
 
 
2087	return i;
2088}
2089
2090static void at_xdmac_free_chan_resources(struct dma_chan *chan)
2091{
2092	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
2093	struct at_xdmac		*atxdmac = to_at_xdmac(chan->device);
2094	struct at_xdmac_desc	*desc, *_desc;
2095
2096	list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) {
2097		dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc);
2098		list_del(&desc->desc_node);
2099		dma_pool_free(atxdmac->at_xdmac_desc_pool, desc, desc->tx_dma_desc.phys);
2100	}
2101
2102	return;
2103}
2104
2105static void at_xdmac_axi_config(struct platform_device *pdev)
2106{
2107	struct at_xdmac	*atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2108	bool dev_m2m = false;
2109	u32 dma_requests;
2110
2111	if (!atxdmac->layout->axi_config)
2112		return; /* Not supported */
2113
2114	if (!of_property_read_u32(pdev->dev.of_node, "dma-requests",
2115				  &dma_requests)) {
2116		dev_info(&pdev->dev, "controller in mem2mem mode.\n");
2117		dev_m2m = true;
2118	}
2119
2120	if (dev_m2m) {
2121		at_xdmac_write(atxdmac, AT_XDMAC_GCFG, AT_XDMAC_GCFG_M2M);
2122		at_xdmac_write(atxdmac, AT_XDMAC_GWAC, AT_XDMAC_GWAC_M2M);
2123	} else {
2124		at_xdmac_write(atxdmac, AT_XDMAC_GCFG, AT_XDMAC_GCFG_P2M);
2125		at_xdmac_write(atxdmac, AT_XDMAC_GWAC, AT_XDMAC_GWAC_P2M);
2126	}
2127}
2128
2129static int __maybe_unused atmel_xdmac_prepare(struct device *dev)
2130{
2131	struct at_xdmac		*atxdmac = dev_get_drvdata(dev);
 
2132	struct dma_chan		*chan, *_chan;
2133
2134	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
2135		struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
2136
2137		/* Wait for transfer completion, except in cyclic case. */
2138		if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan))
2139			return -EAGAIN;
2140	}
2141	return 0;
2142}
 
 
 
2143
2144static int __maybe_unused atmel_xdmac_suspend(struct device *dev)
 
2145{
2146	struct at_xdmac		*atxdmac = dev_get_drvdata(dev);
 
2147	struct dma_chan		*chan, *_chan;
2148	int			ret;
2149
2150	ret = pm_runtime_resume_and_get(atxdmac->dev);
2151	if (ret < 0)
2152		return ret;
2153
2154	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
2155		struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
2156
2157		atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
2158		if (at_xdmac_chan_is_cyclic(atchan)) {
2159			if (!at_xdmac_chan_is_paused(atchan)) {
2160				dev_warn(chan2dev(chan), "%s: channel %d not paused\n",
2161					 __func__, chan->chan_id);
2162				at_xdmac_device_pause_internal(atchan);
2163				at_xdmac_runtime_suspend_descriptors(atchan);
2164			}
2165			atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
2166			atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
2167			atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC);
2168		}
2169	}
2170	atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
2171	atxdmac->save_gs = at_xdmac_read(atxdmac, AT_XDMAC_GS);
2172
2173	at_xdmac_off(atxdmac, false);
2174	pm_runtime_mark_last_busy(atxdmac->dev);
2175	pm_runtime_put_noidle(atxdmac->dev);
2176	clk_disable_unprepare(atxdmac->clk);
2177
2178	return 0;
2179}
2180
2181static int __maybe_unused atmel_xdmac_resume(struct device *dev)
2182{
2183	struct at_xdmac		*atxdmac = dev_get_drvdata(dev);
 
2184	struct at_xdmac_chan	*atchan;
2185	struct dma_chan		*chan, *_chan;
2186	struct platform_device	*pdev = container_of(dev, struct platform_device, dev);
2187	int			i, ret;
2188
2189	ret = clk_prepare_enable(atxdmac->clk);
2190	if (ret)
2191		return ret;
2192
2193	pm_runtime_get_noresume(atxdmac->dev);
2194
2195	at_xdmac_axi_config(pdev);
2196
2197	/* Clear pending interrupts. */
2198	for (i = 0; i < atxdmac->dma.chancnt; i++) {
2199		atchan = &atxdmac->chan[i];
2200		while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2201			cpu_relax();
2202	}
2203
2204	at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim);
 
2205	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
2206		atchan = to_at_xdmac_chan(chan);
2207
2208		at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
2209		if (at_xdmac_chan_is_cyclic(atchan)) {
2210			/*
2211			 * Resume only channels not explicitly paused by
2212			 * consumers.
2213			 */
2214			if (at_xdmac_chan_is_paused_internal(atchan)) {
2215				ret = at_xdmac_runtime_resume_descriptors(atchan);
2216				if (ret < 0)
2217					return ret;
2218				at_xdmac_device_resume_internal(atchan);
2219			}
2220
2221			/*
2222			 * We may resume from a deep sleep state where power
2223			 * to DMA controller is cut-off. Thus, restore the
2224			 * suspend state of channels set though dmaengine API.
2225			 */
2226			else if (at_xdmac_chan_is_paused(atchan))
2227				at_xdmac_device_pause_set(atxdmac, atchan);
2228
2229			at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
2230			at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
2231			at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim);
2232			wmb();
2233			if (atxdmac->save_gs & atchan->mask)
2234				at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
2235		}
2236	}
2237
2238	pm_runtime_mark_last_busy(atxdmac->dev);
2239	pm_runtime_put_autosuspend(atxdmac->dev);
2240
2241	return 0;
2242}
2243
2244static int __maybe_unused atmel_xdmac_runtime_suspend(struct device *dev)
2245{
2246	struct at_xdmac *atxdmac = dev_get_drvdata(dev);
2247
2248	clk_disable(atxdmac->clk);
2249
2250	return 0;
2251}
2252
2253static int __maybe_unused atmel_xdmac_runtime_resume(struct device *dev)
2254{
2255	struct at_xdmac *atxdmac = dev_get_drvdata(dev);
2256
2257	return clk_enable(atxdmac->clk);
2258}
2259
2260static int at_xdmac_probe(struct platform_device *pdev)
2261{
 
2262	struct at_xdmac	*atxdmac;
2263	int		irq, nr_channels, i, ret;
2264	void __iomem	*base;
2265	u32		reg;
2266
 
 
 
 
2267	irq = platform_get_irq(pdev, 0);
2268	if (irq < 0)
2269		return irq;
2270
2271	base = devm_platform_ioremap_resource(pdev, 0);
2272	if (IS_ERR(base))
2273		return PTR_ERR(base);
2274
2275	/*
2276	 * Read number of xdmac channels, read helper function can't be used
2277	 * since atxdmac is not yet allocated and we need to know the number
2278	 * of channels to do the allocation.
2279	 */
2280	reg = readl_relaxed(base + AT_XDMAC_GTYPE);
2281	nr_channels = AT_XDMAC_NB_CH(reg);
2282	if (nr_channels > AT_XDMAC_MAX_CHAN) {
2283		dev_err(&pdev->dev, "invalid number of channels (%u)\n",
2284			nr_channels);
2285		return -EINVAL;
2286	}
2287
2288	atxdmac = devm_kzalloc(&pdev->dev,
2289			       struct_size(atxdmac, chan, nr_channels),
2290			       GFP_KERNEL);
2291	if (!atxdmac) {
2292		dev_err(&pdev->dev, "can't allocate at_xdmac structure\n");
2293		return -ENOMEM;
2294	}
2295
2296	atxdmac->regs = base;
2297	atxdmac->irq = irq;
2298	atxdmac->dev = &pdev->dev;
2299
2300	atxdmac->layout = of_device_get_match_data(&pdev->dev);
2301	if (!atxdmac->layout)
2302		return -ENODEV;
2303
2304	atxdmac->clk = devm_clk_get(&pdev->dev, "dma_clk");
2305	if (IS_ERR(atxdmac->clk)) {
2306		dev_err(&pdev->dev, "can't get dma_clk\n");
2307		return PTR_ERR(atxdmac->clk);
2308	}
2309
2310	/* Do not use dev res to prevent races with tasklet */
2311	ret = request_irq(atxdmac->irq, at_xdmac_interrupt, 0, "at_xdmac", atxdmac);
2312	if (ret) {
2313		dev_err(&pdev->dev, "can't request irq\n");
2314		return ret;
2315	}
2316
2317	ret = clk_prepare_enable(atxdmac->clk);
2318	if (ret) {
2319		dev_err(&pdev->dev, "can't prepare or enable clock\n");
2320		goto err_free_irq;
2321	}
2322
2323	atxdmac->at_xdmac_desc_pool =
2324		dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
2325				sizeof(struct at_xdmac_desc), 4, 0);
2326	if (!atxdmac->at_xdmac_desc_pool) {
2327		dev_err(&pdev->dev, "no memory for descriptors dma pool\n");
2328		ret = -ENOMEM;
2329		goto err_clk_disable;
2330	}
2331
2332	dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask);
2333	dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask);
2334	dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask);
2335	dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask);
2336	dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask);
2337	dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask);
2338	/*
2339	 * Without DMA_PRIVATE the driver is not able to allocate more than
2340	 * one channel, second allocation fails in private_candidate.
2341	 */
2342	dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask);
2343	atxdmac->dma.dev				= &pdev->dev;
2344	atxdmac->dma.device_alloc_chan_resources	= at_xdmac_alloc_chan_resources;
2345	atxdmac->dma.device_free_chan_resources		= at_xdmac_free_chan_resources;
2346	atxdmac->dma.device_tx_status			= at_xdmac_tx_status;
2347	atxdmac->dma.device_issue_pending		= at_xdmac_issue_pending;
2348	atxdmac->dma.device_prep_dma_cyclic		= at_xdmac_prep_dma_cyclic;
2349	atxdmac->dma.device_prep_interleaved_dma	= at_xdmac_prep_interleaved;
2350	atxdmac->dma.device_prep_dma_memcpy		= at_xdmac_prep_dma_memcpy;
2351	atxdmac->dma.device_prep_dma_memset		= at_xdmac_prep_dma_memset;
2352	atxdmac->dma.device_prep_dma_memset_sg		= at_xdmac_prep_dma_memset_sg;
2353	atxdmac->dma.device_prep_slave_sg		= at_xdmac_prep_slave_sg;
2354	atxdmac->dma.device_config			= at_xdmac_device_config;
2355	atxdmac->dma.device_pause			= at_xdmac_device_pause;
2356	atxdmac->dma.device_resume			= at_xdmac_device_resume;
2357	atxdmac->dma.device_terminate_all		= at_xdmac_device_terminate_all;
2358	atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2359	atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2360	atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
2361	atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
2362
2363	platform_set_drvdata(pdev, atxdmac);
2364
2365	pm_runtime_set_autosuspend_delay(&pdev->dev, 500);
2366	pm_runtime_use_autosuspend(&pdev->dev);
2367	pm_runtime_set_active(&pdev->dev);
2368	pm_runtime_enable(&pdev->dev);
2369	pm_runtime_get_noresume(&pdev->dev);
2370
2371	/* Init channels. */
2372	INIT_LIST_HEAD(&atxdmac->dma.channels);
2373
2374	/* Disable all chans and interrupts. */
2375	at_xdmac_off(atxdmac, true);
2376
2377	for (i = 0; i < nr_channels; i++) {
2378		struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2379
2380		atchan->chan.device = &atxdmac->dma;
2381		list_add_tail(&atchan->chan.device_node,
2382			      &atxdmac->dma.channels);
2383
2384		atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, i);
2385		atchan->mask = 1 << i;
2386
2387		spin_lock_init(&atchan->lock);
2388		INIT_LIST_HEAD(&atchan->xfers_list);
2389		INIT_LIST_HEAD(&atchan->free_descs_list);
2390		tasklet_setup(&atchan->tasklet, at_xdmac_tasklet);
 
2391
2392		/* Clear pending interrupts. */
2393		while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2394			cpu_relax();
2395	}
 
2396
2397	ret = dma_async_device_register(&atxdmac->dma);
2398	if (ret) {
2399		dev_err(&pdev->dev, "fail to register DMA engine device\n");
2400		goto err_pm_disable;
2401	}
2402
2403	ret = of_dma_controller_register(pdev->dev.of_node,
2404					 at_xdmac_xlate, atxdmac);
2405	if (ret) {
2406		dev_err(&pdev->dev, "could not register of dma controller\n");
2407		goto err_dma_unregister;
2408	}
2409
2410	dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n",
2411		 nr_channels, atxdmac->regs);
2412
2413	at_xdmac_axi_config(pdev);
2414
2415	pm_runtime_mark_last_busy(&pdev->dev);
2416	pm_runtime_put_autosuspend(&pdev->dev);
2417
2418	return 0;
2419
2420err_dma_unregister:
2421	dma_async_device_unregister(&atxdmac->dma);
2422err_pm_disable:
2423	pm_runtime_put_noidle(&pdev->dev);
2424	pm_runtime_disable(&pdev->dev);
2425	pm_runtime_set_suspended(&pdev->dev);
2426	pm_runtime_dont_use_autosuspend(&pdev->dev);
2427err_clk_disable:
2428	clk_disable_unprepare(atxdmac->clk);
2429err_free_irq:
2430	free_irq(atxdmac->irq, atxdmac);
2431	return ret;
2432}
2433
2434static void at_xdmac_remove(struct platform_device *pdev)
2435{
2436	struct at_xdmac	*atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2437	int		i;
2438
2439	at_xdmac_off(atxdmac, true);
2440	of_dma_controller_free(pdev->dev.of_node);
2441	dma_async_device_unregister(&atxdmac->dma);
2442	pm_runtime_disable(atxdmac->dev);
2443	pm_runtime_set_suspended(&pdev->dev);
2444	pm_runtime_dont_use_autosuspend(&pdev->dev);
2445	clk_disable_unprepare(atxdmac->clk);
2446
2447	free_irq(atxdmac->irq, atxdmac);
2448
2449	for (i = 0; i < atxdmac->dma.chancnt; i++) {
2450		struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2451
2452		tasklet_kill(&atchan->tasklet);
2453		at_xdmac_free_chan_resources(&atchan->chan);
2454	}
 
 
2455}
2456
2457static const struct dev_pm_ops __maybe_unused atmel_xdmac_dev_pm_ops = {
2458	.prepare	= atmel_xdmac_prepare,
2459	SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume)
2460	SET_RUNTIME_PM_OPS(atmel_xdmac_runtime_suspend,
2461			   atmel_xdmac_runtime_resume, NULL)
2462};
2463
2464static const struct of_device_id atmel_xdmac_dt_ids[] = {
2465	{
2466		.compatible = "atmel,sama5d4-dma",
2467		.data = &at_xdmac_sama5d4_layout,
2468	}, {
2469		.compatible = "microchip,sama7g5-dma",
2470		.data = &at_xdmac_sama7g5_layout,
2471	}, {
2472		/* sentinel */
2473	}
2474};
2475MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids);
2476
2477static struct platform_driver at_xdmac_driver = {
2478	.probe		= at_xdmac_probe,
2479	.remove_new	= at_xdmac_remove,
2480	.driver = {
2481		.name		= "at_xdmac",
2482		.of_match_table	= of_match_ptr(atmel_xdmac_dt_ids),
2483		.pm		= pm_ptr(&atmel_xdmac_dev_pm_ops),
2484	}
2485};
2486
2487static int __init at_xdmac_init(void)
2488{
2489	return platform_driver_register(&at_xdmac_driver);
2490}
2491subsys_initcall(at_xdmac_init);
2492
2493static void __exit at_xdmac_exit(void)
2494{
2495	platform_driver_unregister(&at_xdmac_driver);
2496}
2497module_exit(at_xdmac_exit);
2498
2499MODULE_DESCRIPTION("Atmel Extended DMA Controller driver");
2500MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
2501MODULE_LICENSE("GPL");
v4.6
 
   1/*
   2 * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems)
   3 *
   4 * Copyright (C) 2014 Atmel Corporation
   5 *
   6 * Author: Ludovic Desroches <ludovic.desroches@atmel.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify it
   9 * under the terms of the GNU General Public License version 2 as published by
  10 * the Free Software Foundation.
  11 *
  12 * This program is distributed in the hope that it will be useful, but WITHOUT
  13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15 * more details.
  16 *
  17 * You should have received a copy of the GNU General Public License along with
  18 * this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21#include <asm/barrier.h>
  22#include <dt-bindings/dma/at91.h>
  23#include <linux/clk.h>
  24#include <linux/dmaengine.h>
  25#include <linux/dmapool.h>
  26#include <linux/interrupt.h>
  27#include <linux/irq.h>
  28#include <linux/kernel.h>
  29#include <linux/list.h>
  30#include <linux/module.h>
  31#include <linux/of_dma.h>
  32#include <linux/of_platform.h>
  33#include <linux/platform_device.h>
  34#include <linux/pm.h>
 
  35
  36#include "dmaengine.h"
  37
  38/* Global registers */
  39#define AT_XDMAC_GTYPE		0x00	/* Global Type Register */
  40#define		AT_XDMAC_NB_CH(i)	(((i) & 0x1F) + 1)		/* Number of Channels Minus One */
  41#define		AT_XDMAC_FIFO_SZ(i)	(((i) >> 5) & 0x7FF)		/* Number of Bytes */
  42#define		AT_XDMAC_NB_REQ(i)	((((i) >> 16) & 0x3F) + 1)	/* Number of Peripheral Requests Minus One */
  43#define AT_XDMAC_GCFG		0x04	/* Global Configuration Register */
 
 
 
 
 
 
 
 
 
 
  44#define AT_XDMAC_GWAC		0x08	/* Global Weighted Arbiter Configuration Register */
 
 
 
 
 
 
 
  45#define AT_XDMAC_GIE		0x0C	/* Global Interrupt Enable Register */
  46#define AT_XDMAC_GID		0x10	/* Global Interrupt Disable Register */
  47#define AT_XDMAC_GIM		0x14	/* Global Interrupt Mask Register */
  48#define AT_XDMAC_GIS		0x18	/* Global Interrupt Status Register */
  49#define AT_XDMAC_GE		0x1C	/* Global Channel Enable Register */
  50#define AT_XDMAC_GD		0x20	/* Global Channel Disable Register */
  51#define AT_XDMAC_GS		0x24	/* Global Channel Status Register */
  52#define AT_XDMAC_GRS		0x28	/* Global Channel Read Suspend Register */
  53#define AT_XDMAC_GWS		0x2C	/* Global Write Suspend Register */
  54#define AT_XDMAC_GRWS		0x30	/* Global Channel Read Write Suspend Register */
  55#define AT_XDMAC_GRWR		0x34	/* Global Channel Read Write Resume Register */
  56#define AT_XDMAC_GSWR		0x38	/* Global Channel Software Request Register */
  57#define AT_XDMAC_GSWS		0x3C	/* Global channel Software Request Status Register */
  58#define AT_XDMAC_GSWF		0x40	/* Global Channel Software Flush Request Register */
  59#define AT_XDMAC_VERSION	0xFFC	/* XDMAC Version Register */
  60
  61/* Channel relative registers offsets */
  62#define AT_XDMAC_CIE		0x00	/* Channel Interrupt Enable Register */
  63#define		AT_XDMAC_CIE_BIE	BIT(0)	/* End of Block Interrupt Enable Bit */
  64#define		AT_XDMAC_CIE_LIE	BIT(1)	/* End of Linked List Interrupt Enable Bit */
  65#define		AT_XDMAC_CIE_DIE	BIT(2)	/* End of Disable Interrupt Enable Bit */
  66#define		AT_XDMAC_CIE_FIE	BIT(3)	/* End of Flush Interrupt Enable Bit */
  67#define		AT_XDMAC_CIE_RBEIE	BIT(4)	/* Read Bus Error Interrupt Enable Bit */
  68#define		AT_XDMAC_CIE_WBEIE	BIT(5)	/* Write Bus Error Interrupt Enable Bit */
  69#define		AT_XDMAC_CIE_ROIE	BIT(6)	/* Request Overflow Interrupt Enable Bit */
  70#define AT_XDMAC_CID		0x04	/* Channel Interrupt Disable Register */
  71#define		AT_XDMAC_CID_BID	BIT(0)	/* End of Block Interrupt Disable Bit */
  72#define		AT_XDMAC_CID_LID	BIT(1)	/* End of Linked List Interrupt Disable Bit */
  73#define		AT_XDMAC_CID_DID	BIT(2)	/* End of Disable Interrupt Disable Bit */
  74#define		AT_XDMAC_CID_FID	BIT(3)	/* End of Flush Interrupt Disable Bit */
  75#define		AT_XDMAC_CID_RBEID	BIT(4)	/* Read Bus Error Interrupt Disable Bit */
  76#define		AT_XDMAC_CID_WBEID	BIT(5)	/* Write Bus Error Interrupt Disable Bit */
  77#define		AT_XDMAC_CID_ROID	BIT(6)	/* Request Overflow Interrupt Disable Bit */
  78#define AT_XDMAC_CIM		0x08	/* Channel Interrupt Mask Register */
  79#define		AT_XDMAC_CIM_BIM	BIT(0)	/* End of Block Interrupt Mask Bit */
  80#define		AT_XDMAC_CIM_LIM	BIT(1)	/* End of Linked List Interrupt Mask Bit */
  81#define		AT_XDMAC_CIM_DIM	BIT(2)	/* End of Disable Interrupt Mask Bit */
  82#define		AT_XDMAC_CIM_FIM	BIT(3)	/* End of Flush Interrupt Mask Bit */
  83#define		AT_XDMAC_CIM_RBEIM	BIT(4)	/* Read Bus Error Interrupt Mask Bit */
  84#define		AT_XDMAC_CIM_WBEIM	BIT(5)	/* Write Bus Error Interrupt Mask Bit */
  85#define		AT_XDMAC_CIM_ROIM	BIT(6)	/* Request Overflow Interrupt Mask Bit */
  86#define AT_XDMAC_CIS		0x0C	/* Channel Interrupt Status Register */
  87#define		AT_XDMAC_CIS_BIS	BIT(0)	/* End of Block Interrupt Status Bit */
  88#define		AT_XDMAC_CIS_LIS	BIT(1)	/* End of Linked List Interrupt Status Bit */
  89#define		AT_XDMAC_CIS_DIS	BIT(2)	/* End of Disable Interrupt Status Bit */
  90#define		AT_XDMAC_CIS_FIS	BIT(3)	/* End of Flush Interrupt Status Bit */
  91#define		AT_XDMAC_CIS_RBEIS	BIT(4)	/* Read Bus Error Interrupt Status Bit */
  92#define		AT_XDMAC_CIS_WBEIS	BIT(5)	/* Write Bus Error Interrupt Status Bit */
  93#define		AT_XDMAC_CIS_ROIS	BIT(6)	/* Request Overflow Interrupt Status Bit */
  94#define AT_XDMAC_CSA		0x10	/* Channel Source Address Register */
  95#define AT_XDMAC_CDA		0x14	/* Channel Destination Address Register */
  96#define AT_XDMAC_CNDA		0x18	/* Channel Next Descriptor Address Register */
  97#define		AT_XDMAC_CNDA_NDAIF(i)	((i) & 0x1)			/* Channel x Next Descriptor Interface */
  98#define		AT_XDMAC_CNDA_NDA(i)	((i) & 0xfffffffc)		/* Channel x Next Descriptor Address */
  99#define AT_XDMAC_CNDC		0x1C	/* Channel Next Descriptor Control Register */
 100#define		AT_XDMAC_CNDC_NDE		(0x1 << 0)		/* Channel x Next Descriptor Enable */
 101#define		AT_XDMAC_CNDC_NDSUP		(0x1 << 1)		/* Channel x Next Descriptor Source Update */
 102#define		AT_XDMAC_CNDC_NDDUP		(0x1 << 2)		/* Channel x Next Descriptor Destination Update */
 
 103#define		AT_XDMAC_CNDC_NDVIEW_NDV0	(0x0 << 3)		/* Channel x Next Descriptor View 0 */
 104#define		AT_XDMAC_CNDC_NDVIEW_NDV1	(0x1 << 3)		/* Channel x Next Descriptor View 1 */
 105#define		AT_XDMAC_CNDC_NDVIEW_NDV2	(0x2 << 3)		/* Channel x Next Descriptor View 2 */
 106#define		AT_XDMAC_CNDC_NDVIEW_NDV3	(0x3 << 3)		/* Channel x Next Descriptor View 3 */
 107#define AT_XDMAC_CUBC		0x20	/* Channel Microblock Control Register */
 108#define AT_XDMAC_CBC		0x24	/* Channel Block Control Register */
 109#define AT_XDMAC_CC		0x28	/* Channel Configuration Register */
 110#define		AT_XDMAC_CC_TYPE	(0x1 << 0)	/* Channel Transfer Type */
 111#define			AT_XDMAC_CC_TYPE_MEM_TRAN	(0x0 << 0)	/* Memory to Memory Transfer */
 112#define			AT_XDMAC_CC_TYPE_PER_TRAN	(0x1 << 0)	/* Peripheral to Memory or Memory to Peripheral Transfer */
 113#define		AT_XDMAC_CC_MBSIZE_MASK	(0x3 << 1)
 114#define			AT_XDMAC_CC_MBSIZE_SINGLE	(0x0 << 1)
 115#define			AT_XDMAC_CC_MBSIZE_FOUR		(0x1 << 1)
 116#define			AT_XDMAC_CC_MBSIZE_EIGHT	(0x2 << 1)
 117#define			AT_XDMAC_CC_MBSIZE_SIXTEEN	(0x3 << 1)
 118#define		AT_XDMAC_CC_DSYNC	(0x1 << 4)	/* Channel Synchronization */
 119#define			AT_XDMAC_CC_DSYNC_PER2MEM	(0x0 << 4)
 120#define			AT_XDMAC_CC_DSYNC_MEM2PER	(0x1 << 4)
 121#define		AT_XDMAC_CC_PROT	(0x1 << 5)	/* Channel Protection */
 122#define			AT_XDMAC_CC_PROT_SEC		(0x0 << 5)
 123#define			AT_XDMAC_CC_PROT_UNSEC		(0x1 << 5)
 124#define		AT_XDMAC_CC_SWREQ	(0x1 << 6)	/* Channel Software Request Trigger */
 125#define			AT_XDMAC_CC_SWREQ_HWR_CONNECTED	(0x0 << 6)
 126#define			AT_XDMAC_CC_SWREQ_SWR_CONNECTED	(0x1 << 6)
 127#define		AT_XDMAC_CC_MEMSET	(0x1 << 7)	/* Channel Fill Block of memory */
 128#define			AT_XDMAC_CC_MEMSET_NORMAL_MODE	(0x0 << 7)
 129#define			AT_XDMAC_CC_MEMSET_HW_MODE	(0x1 << 7)
 130#define		AT_XDMAC_CC_CSIZE(i)	((0x7 & (i)) << 8)	/* Channel Chunk Size */
 131#define		AT_XDMAC_CC_DWIDTH_OFFSET	11
 132#define		AT_XDMAC_CC_DWIDTH_MASK	(0x3 << AT_XDMAC_CC_DWIDTH_OFFSET)
 133#define		AT_XDMAC_CC_DWIDTH(i)	((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET)	/* Channel Data Width */
 134#define			AT_XDMAC_CC_DWIDTH_BYTE		0x0
 135#define			AT_XDMAC_CC_DWIDTH_HALFWORD	0x1
 136#define			AT_XDMAC_CC_DWIDTH_WORD		0x2
 137#define			AT_XDMAC_CC_DWIDTH_DWORD	0x3
 138#define		AT_XDMAC_CC_SIF(i)	((0x1 & (i)) << 13)	/* Channel Source Interface Identifier */
 139#define		AT_XDMAC_CC_DIF(i)	((0x1 & (i)) << 14)	/* Channel Destination Interface Identifier */
 140#define		AT_XDMAC_CC_SAM_MASK	(0x3 << 16)	/* Channel Source Addressing Mode */
 141#define			AT_XDMAC_CC_SAM_FIXED_AM	(0x0 << 16)
 142#define			AT_XDMAC_CC_SAM_INCREMENTED_AM	(0x1 << 16)
 143#define			AT_XDMAC_CC_SAM_UBS_AM		(0x2 << 16)
 144#define			AT_XDMAC_CC_SAM_UBS_DS_AM	(0x3 << 16)
 145#define		AT_XDMAC_CC_DAM_MASK	(0x3 << 18)	/* Channel Source Addressing Mode */
 146#define			AT_XDMAC_CC_DAM_FIXED_AM	(0x0 << 18)
 147#define			AT_XDMAC_CC_DAM_INCREMENTED_AM	(0x1 << 18)
 148#define			AT_XDMAC_CC_DAM_UBS_AM		(0x2 << 18)
 149#define			AT_XDMAC_CC_DAM_UBS_DS_AM	(0x3 << 18)
 150#define		AT_XDMAC_CC_INITD	(0x1 << 21)	/* Channel Initialization Terminated (read only) */
 151#define			AT_XDMAC_CC_INITD_TERMINATED	(0x0 << 21)
 152#define			AT_XDMAC_CC_INITD_IN_PROGRESS	(0x1 << 21)
 153#define		AT_XDMAC_CC_RDIP	(0x1 << 22)	/* Read in Progress (read only) */
 154#define			AT_XDMAC_CC_RDIP_DONE		(0x0 << 22)
 155#define			AT_XDMAC_CC_RDIP_IN_PROGRESS	(0x1 << 22)
 156#define		AT_XDMAC_CC_WRIP	(0x1 << 23)	/* Write in Progress (read only) */
 157#define			AT_XDMAC_CC_WRIP_DONE		(0x0 << 23)
 158#define			AT_XDMAC_CC_WRIP_IN_PROGRESS	(0x1 << 23)
 159#define		AT_XDMAC_CC_PERID(i)	(0x7f & (i) << 24)	/* Channel Peripheral Identifier */
 160#define AT_XDMAC_CDS_MSP	0x2C	/* Channel Data Stride Memory Set Pattern */
 161#define AT_XDMAC_CSUS		0x30	/* Channel Source Microblock Stride */
 162#define AT_XDMAC_CDUS		0x34	/* Channel Destination Microblock Stride */
 163
 164#define AT_XDMAC_CHAN_REG_BASE	0x50	/* Channel registers base address */
 165
 166/* Microblock control members */
 167#define AT_XDMAC_MBR_UBC_UBLEN_MAX	0xFFFFFFUL	/* Maximum Microblock Length */
 168#define AT_XDMAC_MBR_UBC_NDE		(0x1 << 24)	/* Next Descriptor Enable */
 169#define AT_XDMAC_MBR_UBC_NSEN		(0x1 << 25)	/* Next Descriptor Source Update */
 170#define AT_XDMAC_MBR_UBC_NDEN		(0x1 << 26)	/* Next Descriptor Destination Update */
 171#define AT_XDMAC_MBR_UBC_NDV0		(0x0 << 27)	/* Next Descriptor View 0 */
 172#define AT_XDMAC_MBR_UBC_NDV1		(0x1 << 27)	/* Next Descriptor View 1 */
 173#define AT_XDMAC_MBR_UBC_NDV2		(0x2 << 27)	/* Next Descriptor View 2 */
 174#define AT_XDMAC_MBR_UBC_NDV3		(0x3 << 27)	/* Next Descriptor View 3 */
 175
 176#define AT_XDMAC_MAX_CHAN	0x20
 177#define AT_XDMAC_MAX_CSIZE	16	/* 16 data */
 178#define AT_XDMAC_MAX_DWIDTH	8	/* 64 bits */
 179#define AT_XDMAC_RESIDUE_MAX_RETRIES	5
 180
 181#define AT_XDMAC_DMA_BUSWIDTHS\
 182	(BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
 183	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\
 184	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\
 185	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\
 186	BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
 187
 188enum atc_status {
 189	AT_XDMAC_CHAN_IS_CYCLIC = 0,
 190	AT_XDMAC_CHAN_IS_PAUSED,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 191};
 192
 193/* ----- Channels ----- */
 194struct at_xdmac_chan {
 195	struct dma_chan			chan;
 196	void __iomem			*ch_regs;
 197	u32				mask;		/* Channel Mask */
 198	u32				cfg;		/* Channel Configuration Register */
 199	u8				perid;		/* Peripheral ID */
 200	u8				perif;		/* Peripheral Interface */
 201	u8				memif;		/* Memory Interface */
 202	u32				save_cc;
 203	u32				save_cim;
 204	u32				save_cnda;
 205	u32				save_cndc;
 
 206	unsigned long			status;
 207	struct tasklet_struct		tasklet;
 208	struct dma_slave_config		sconfig;
 209
 210	spinlock_t			lock;
 211
 212	struct list_head		xfers_list;
 213	struct list_head		free_descs_list;
 214};
 215
 216
 217/* ----- Controller ----- */
 218struct at_xdmac {
 219	struct dma_device	dma;
 220	void __iomem		*regs;
 
 221	int			irq;
 222	struct clk		*clk;
 223	u32			save_gim;
 224	u32			save_gs;
 225	struct dma_pool		*at_xdmac_desc_pool;
 226	struct at_xdmac_chan	chan[0];
 
 227};
 228
 229
 230/* ----- Descriptors ----- */
 231
 232/* Linked List Descriptor */
 233struct at_xdmac_lld {
 234	dma_addr_t	mbr_nda;	/* Next Descriptor Member */
 235	u32		mbr_ubc;	/* Microblock Control Member */
 236	dma_addr_t	mbr_sa;		/* Source Address Member */
 237	dma_addr_t	mbr_da;		/* Destination Address Member */
 238	u32		mbr_cfg;	/* Configuration Register */
 239	u32		mbr_bc;		/* Block Control Register */
 240	u32		mbr_ds;		/* Data Stride Register */
 241	u32		mbr_sus;	/* Source Microblock Stride Register */
 242	u32		mbr_dus;	/* Destination Microblock Stride Register */
 243};
 244
 245
 246struct at_xdmac_desc {
 247	struct at_xdmac_lld		lld;
 248	enum dma_transfer_direction	direction;
 249	struct dma_async_tx_descriptor	tx_dma_desc;
 250	struct list_head		desc_node;
 251	/* Following members are only used by the first descriptor */
 252	bool				active_xfer;
 253	unsigned int			xfer_size;
 254	struct list_head		descs_list;
 255	struct list_head		xfer_node;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 256};
 257
 258static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb)
 259{
 260	return atxdmac->regs + (AT_XDMAC_CHAN_REG_BASE + chan_nb * 0x40);
 261}
 262
 263#define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg))
 264#define at_xdmac_write(atxdmac, reg, value) \
 265	writel_relaxed((value), (atxdmac)->regs + (reg))
 266
 267#define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg))
 268#define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg))
 269
 270static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan)
 271{
 272	return container_of(dchan, struct at_xdmac_chan, chan);
 273}
 274
 275static struct device *chan2dev(struct dma_chan *chan)
 276{
 277	return &chan->dev->device;
 278}
 279
 280static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev)
 281{
 282	return container_of(ddev, struct at_xdmac, dma);
 283}
 284
 285static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd)
 286{
 287	return container_of(txd, struct at_xdmac_desc, tx_dma_desc);
 288}
 289
 290static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan)
 291{
 292	return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
 293}
 294
 295static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan)
 296{
 297	return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
 298}
 299
 300static inline int at_xdmac_csize(u32 maxburst)
 301{
 302	int csize;
 
 303
 304	csize = ffs(maxburst) - 1;
 305	if (csize > 4)
 306		csize = -EINVAL;
 307
 308	return csize;
 309};
 310
 311static inline u8 at_xdmac_get_dwidth(u32 cfg)
 312{
 313	return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
 314};
 315
 316static unsigned int init_nr_desc_per_channel = 64;
 317module_param(init_nr_desc_per_channel, uint, 0644);
 318MODULE_PARM_DESC(init_nr_desc_per_channel,
 319		 "initial descriptors per channel (default: 64)");
 320
 321
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 322static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan)
 323{
 324	return at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask;
 
 
 
 
 
 
 
 
 
 
 
 
 325}
 326
 327static void at_xdmac_off(struct at_xdmac *atxdmac)
 328{
 
 
 
 
 
 
 
 
 329	at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L);
 330
 331	/* Wait that all chans are disabled. */
 332	while (at_xdmac_read(atxdmac, AT_XDMAC_GS))
 333		cpu_relax();
 334
 335	at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L);
 
 
 
 
 
 
 
 
 
 
 
 
 336}
 337
 338/* Call with lock hold. */
 339static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
 340				struct at_xdmac_desc *first)
 341{
 342	struct at_xdmac	*atxdmac = to_at_xdmac(atchan->chan.device);
 343	u32		reg;
 
 
 
 
 
 344
 345	dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
 346
 347	if (at_xdmac_chan_is_enabled(atchan))
 348		return;
 349
 350	/* Set transfer as active to not try to start it again. */
 351	first->active_xfer = true;
 352
 353	/* Tell xdmac where to get the first descriptor. */
 354	reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys)
 355	      | AT_XDMAC_CNDA_NDAIF(atchan->memif);
 
 
 356	at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
 357
 358	/*
 359	 * When doing non cyclic transfer we need to use the next
 360	 * descriptor view 2 since some fields of the configuration register
 361	 * depend on transfer size and src/dest addresses.
 362	 */
 363	if (at_xdmac_chan_is_cyclic(atchan))
 364		reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
 365	else if (first->lld.mbr_ubc & AT_XDMAC_MBR_UBC_NDV3)
 
 366		reg = AT_XDMAC_CNDC_NDVIEW_NDV3;
 367	else
 368		reg = AT_XDMAC_CNDC_NDVIEW_NDV2;
 369	/*
 370	 * Even if the register will be updated from the configuration in the
 371	 * descriptor when using view 2 or higher, the PROT bit won't be set
 372	 * properly. This bit can be modified only by using the channel
 373	 * configuration register.
 374	 */
 375	at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
 376
 377	reg |= AT_XDMAC_CNDC_NDDUP
 378	       | AT_XDMAC_CNDC_NDSUP
 379	       | AT_XDMAC_CNDC_NDE;
 380	at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg);
 381
 382	dev_vdbg(chan2dev(&atchan->chan),
 383		 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
 384		 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
 385		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
 386		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
 387		 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
 388		 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
 389		 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 390
 391	at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
 392	reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE | AT_XDMAC_CIE_ROIE;
 
 
 
 
 
 
 393	/*
 394	 * There is no end of list when doing cyclic dma, we need to get
 395	 * an interrupt after each periods.
 396	 */
 397	if (at_xdmac_chan_is_cyclic(atchan))
 398		at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
 399				    reg | AT_XDMAC_CIE_BIE);
 400	else
 401		at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
 402				    reg | AT_XDMAC_CIE_LIE);
 403	at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask);
 404	dev_vdbg(chan2dev(&atchan->chan),
 405		 "%s: enable channel (0x%08x)\n", __func__, atchan->mask);
 406	wmb();
 407	at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
 408
 409	dev_vdbg(chan2dev(&atchan->chan),
 410		 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
 411		 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
 412		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
 413		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
 414		 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
 415		 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
 416		 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 417
 418}
 419
 420static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx)
 421{
 422	struct at_xdmac_desc	*desc = txd_to_at_desc(tx);
 423	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(tx->chan);
 424	dma_cookie_t		cookie;
 425	unsigned long		irqflags;
 426
 427	spin_lock_irqsave(&atchan->lock, irqflags);
 428	cookie = dma_cookie_assign(tx);
 429
 
 
 
 430	dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n",
 431		 __func__, atchan, desc);
 432	list_add_tail(&desc->xfer_node, &atchan->xfers_list);
 433	if (list_is_singular(&atchan->xfers_list))
 434		at_xdmac_start_xfer(atchan, desc);
 435
 436	spin_unlock_irqrestore(&atchan->lock, irqflags);
 437	return cookie;
 438}
 439
 440static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan,
 441						 gfp_t gfp_flags)
 442{
 443	struct at_xdmac_desc	*desc;
 444	struct at_xdmac		*atxdmac = to_at_xdmac(chan->device);
 445	dma_addr_t		phys;
 446
 447	desc = dma_pool_alloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys);
 448	if (desc) {
 449		memset(desc, 0, sizeof(*desc));
 450		INIT_LIST_HEAD(&desc->descs_list);
 451		dma_async_tx_descriptor_init(&desc->tx_dma_desc, chan);
 452		desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit;
 453		desc->tx_dma_desc.phys = phys;
 454	}
 455
 456	return desc;
 457}
 458
 459void at_xdmac_init_used_desc(struct at_xdmac_desc *desc)
 460{
 461	memset(&desc->lld, 0, sizeof(desc->lld));
 462	INIT_LIST_HEAD(&desc->descs_list);
 463	desc->direction = DMA_TRANS_NONE;
 464	desc->xfer_size = 0;
 465	desc->active_xfer = false;
 466}
 467
 468/* Call must be protected by lock. */
 469static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan)
 470{
 471	struct at_xdmac_desc *desc;
 472
 473	if (list_empty(&atchan->free_descs_list)) {
 474		desc = at_xdmac_alloc_desc(&atchan->chan, GFP_NOWAIT);
 475	} else {
 476		desc = list_first_entry(&atchan->free_descs_list,
 477					struct at_xdmac_desc, desc_node);
 478		list_del(&desc->desc_node);
 479		at_xdmac_init_used_desc(desc);
 480	}
 481
 482	return desc;
 483}
 484
 485static void at_xdmac_queue_desc(struct dma_chan *chan,
 486				struct at_xdmac_desc *prev,
 487				struct at_xdmac_desc *desc)
 488{
 489	if (!prev || !desc)
 490		return;
 491
 492	prev->lld.mbr_nda = desc->tx_dma_desc.phys;
 493	prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE;
 494
 495	dev_dbg(chan2dev(chan),	"%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
 496		__func__, prev, &prev->lld.mbr_nda);
 497}
 498
 499static inline void at_xdmac_increment_block_count(struct dma_chan *chan,
 500						  struct at_xdmac_desc *desc)
 501{
 502	if (!desc)
 503		return;
 504
 505	desc->lld.mbr_bc++;
 506
 507	dev_dbg(chan2dev(chan),
 508		"%s: incrementing the block count of the desc 0x%p\n",
 509		__func__, desc);
 510}
 511
 512static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
 513				       struct of_dma *of_dma)
 514{
 515	struct at_xdmac		*atxdmac = of_dma->of_dma_data;
 516	struct at_xdmac_chan	*atchan;
 517	struct dma_chan		*chan;
 518	struct device		*dev = atxdmac->dma.dev;
 519
 520	if (dma_spec->args_count != 1) {
 521		dev_err(dev, "dma phandler args: bad number of args\n");
 522		return NULL;
 523	}
 524
 525	chan = dma_get_any_slave_channel(&atxdmac->dma);
 526	if (!chan) {
 527		dev_err(dev, "can't get a dma channel\n");
 528		return NULL;
 529	}
 530
 531	atchan = to_at_xdmac_chan(chan);
 532	atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]);
 533	atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]);
 534	atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]);
 535	dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n",
 536		 atchan->memif, atchan->perif, atchan->perid);
 537
 538	return chan;
 539}
 540
 541static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
 542				      enum dma_transfer_direction direction)
 543{
 544	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 
 545	int			csize, dwidth;
 546
 547	if (direction == DMA_DEV_TO_MEM) {
 548		atchan->cfg =
 549			AT91_XDMAC_DT_PERID(atchan->perid)
 550			| AT_XDMAC_CC_DAM_INCREMENTED_AM
 551			| AT_XDMAC_CC_SAM_FIXED_AM
 552			| AT_XDMAC_CC_DIF(atchan->memif)
 553			| AT_XDMAC_CC_SIF(atchan->perif)
 554			| AT_XDMAC_CC_SWREQ_HWR_CONNECTED
 555			| AT_XDMAC_CC_DSYNC_PER2MEM
 556			| AT_XDMAC_CC_MBSIZE_SIXTEEN
 557			| AT_XDMAC_CC_TYPE_PER_TRAN;
 
 
 
 
 558		csize = ffs(atchan->sconfig.src_maxburst) - 1;
 559		if (csize < 0) {
 560			dev_err(chan2dev(chan), "invalid src maxburst value\n");
 561			return -EINVAL;
 562		}
 563		atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
 564		dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
 565		if (dwidth < 0) {
 566			dev_err(chan2dev(chan), "invalid src addr width value\n");
 567			return -EINVAL;
 568		}
 569		atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
 570	} else if (direction == DMA_MEM_TO_DEV) {
 571		atchan->cfg =
 572			AT91_XDMAC_DT_PERID(atchan->perid)
 573			| AT_XDMAC_CC_DAM_FIXED_AM
 574			| AT_XDMAC_CC_SAM_INCREMENTED_AM
 575			| AT_XDMAC_CC_DIF(atchan->perif)
 576			| AT_XDMAC_CC_SIF(atchan->memif)
 577			| AT_XDMAC_CC_SWREQ_HWR_CONNECTED
 578			| AT_XDMAC_CC_DSYNC_MEM2PER
 579			| AT_XDMAC_CC_MBSIZE_SIXTEEN
 580			| AT_XDMAC_CC_TYPE_PER_TRAN;
 
 
 
 
 581		csize = ffs(atchan->sconfig.dst_maxburst) - 1;
 582		if (csize < 0) {
 583			dev_err(chan2dev(chan), "invalid src maxburst value\n");
 584			return -EINVAL;
 585		}
 586		atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
 587		dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
 588		if (dwidth < 0) {
 589			dev_err(chan2dev(chan), "invalid dst addr width value\n");
 590			return -EINVAL;
 591		}
 592		atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
 593	}
 594
 595	dev_dbg(chan2dev(chan),	"%s: cfg=0x%08x\n", __func__, atchan->cfg);
 596
 597	return 0;
 598}
 599
 600/*
 601 * Only check that maxburst and addr width values are supported by the
 602 * the controller but not that the configuration is good to perform the
 603 * transfer since we don't know the direction at this stage.
 604 */
 605static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
 606{
 607	if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
 608	    || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
 609		return -EINVAL;
 610
 611	if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
 612	    || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
 613		return -EINVAL;
 614
 615	return 0;
 616}
 617
 618static int at_xdmac_set_slave_config(struct dma_chan *chan,
 619				      struct dma_slave_config *sconfig)
 620{
 621	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 622
 623	if (at_xdmac_check_slave_config(sconfig)) {
 624		dev_err(chan2dev(chan), "invalid slave configuration\n");
 625		return -EINVAL;
 626	}
 627
 628	memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
 629
 630	return 0;
 631}
 632
 633static struct dma_async_tx_descriptor *
 634at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 635		       unsigned int sg_len, enum dma_transfer_direction direction,
 636		       unsigned long flags, void *context)
 637{
 638	struct at_xdmac_chan		*atchan = to_at_xdmac_chan(chan);
 639	struct at_xdmac_desc		*first = NULL, *prev = NULL;
 640	struct scatterlist		*sg;
 641	int				i;
 642	unsigned int			xfer_size = 0;
 643	unsigned long			irqflags;
 644	struct dma_async_tx_descriptor	*ret = NULL;
 645
 646	if (!sgl)
 647		return NULL;
 648
 649	if (!is_slave_direction(direction)) {
 650		dev_err(chan2dev(chan), "invalid DMA direction\n");
 651		return NULL;
 652	}
 653
 654	dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n",
 655		 __func__, sg_len,
 656		 direction == DMA_MEM_TO_DEV ? "to device" : "from device",
 657		 flags);
 658
 659	/* Protect dma_sconfig field that can be modified by set_slave_conf. */
 660	spin_lock_irqsave(&atchan->lock, irqflags);
 661
 662	if (at_xdmac_compute_chan_conf(chan, direction))
 663		goto spin_unlock;
 664
 665	/* Prepare descriptors. */
 666	for_each_sg(sgl, sg, sg_len, i) {
 667		struct at_xdmac_desc	*desc = NULL;
 668		u32			len, mem, dwidth, fixed_dwidth;
 669
 670		len = sg_dma_len(sg);
 671		mem = sg_dma_address(sg);
 672		if (unlikely(!len)) {
 673			dev_err(chan2dev(chan), "sg data length is zero\n");
 674			goto spin_unlock;
 675		}
 676		dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n",
 677			 __func__, i, len, mem);
 678
 679		desc = at_xdmac_get_desc(atchan);
 680		if (!desc) {
 681			dev_err(chan2dev(chan), "can't get descriptor\n");
 682			if (first)
 683				list_splice_init(&first->descs_list, &atchan->free_descs_list);
 
 684			goto spin_unlock;
 685		}
 686
 687		/* Linked list descriptor setup. */
 688		if (direction == DMA_DEV_TO_MEM) {
 689			desc->lld.mbr_sa = atchan->sconfig.src_addr;
 690			desc->lld.mbr_da = mem;
 691		} else {
 692			desc->lld.mbr_sa = mem;
 693			desc->lld.mbr_da = atchan->sconfig.dst_addr;
 694		}
 695		dwidth = at_xdmac_get_dwidth(atchan->cfg);
 696		fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
 697			       ? dwidth
 698			       : AT_XDMAC_CC_DWIDTH_BYTE;
 699		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2			/* next descriptor view */
 700			| AT_XDMAC_MBR_UBC_NDEN					/* next descriptor dst parameter update */
 701			| AT_XDMAC_MBR_UBC_NSEN					/* next descriptor src parameter update */
 702			| (len >> fixed_dwidth);				/* microblock length */
 703		desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) |
 704				    AT_XDMAC_CC_DWIDTH(fixed_dwidth);
 705		dev_dbg(chan2dev(chan),
 706			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
 707			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
 708
 709		/* Chain lld. */
 710		if (prev)
 711			at_xdmac_queue_desc(chan, prev, desc);
 712
 713		prev = desc;
 714		if (!first)
 715			first = desc;
 716
 717		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
 718			 __func__, desc, first);
 719		list_add_tail(&desc->desc_node, &first->descs_list);
 720		xfer_size += len;
 721	}
 722
 723
 724	first->tx_dma_desc.flags = flags;
 725	first->xfer_size = xfer_size;
 726	first->direction = direction;
 727	ret = &first->tx_dma_desc;
 728
 729spin_unlock:
 730	spin_unlock_irqrestore(&atchan->lock, irqflags);
 731	return ret;
 732}
 733
 734static struct dma_async_tx_descriptor *
 735at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
 736			 size_t buf_len, size_t period_len,
 737			 enum dma_transfer_direction direction,
 738			 unsigned long flags)
 739{
 740	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 741	struct at_xdmac_desc	*first = NULL, *prev = NULL;
 742	unsigned int		periods = buf_len / period_len;
 743	int			i;
 744	unsigned long		irqflags;
 745
 746	dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n",
 747		__func__, &buf_addr, buf_len, period_len,
 748		direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags);
 749
 750	if (!is_slave_direction(direction)) {
 751		dev_err(chan2dev(chan), "invalid DMA direction\n");
 752		return NULL;
 753	}
 754
 755	if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
 756		dev_err(chan2dev(chan), "channel currently used\n");
 757		return NULL;
 758	}
 759
 760	if (at_xdmac_compute_chan_conf(chan, direction))
 761		return NULL;
 762
 763	for (i = 0; i < periods; i++) {
 764		struct at_xdmac_desc	*desc = NULL;
 765
 766		spin_lock_irqsave(&atchan->lock, irqflags);
 767		desc = at_xdmac_get_desc(atchan);
 768		if (!desc) {
 769			dev_err(chan2dev(chan), "can't get descriptor\n");
 770			if (first)
 771				list_splice_init(&first->descs_list, &atchan->free_descs_list);
 
 772			spin_unlock_irqrestore(&atchan->lock, irqflags);
 773			return NULL;
 774		}
 775		spin_unlock_irqrestore(&atchan->lock, irqflags);
 776		dev_dbg(chan2dev(chan),
 777			"%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
 778			__func__, desc, &desc->tx_dma_desc.phys);
 779
 780		if (direction == DMA_DEV_TO_MEM) {
 781			desc->lld.mbr_sa = atchan->sconfig.src_addr;
 782			desc->lld.mbr_da = buf_addr + i * period_len;
 783		} else {
 784			desc->lld.mbr_sa = buf_addr + i * period_len;
 785			desc->lld.mbr_da = atchan->sconfig.dst_addr;
 786		}
 787		desc->lld.mbr_cfg = atchan->cfg;
 788		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
 789			| AT_XDMAC_MBR_UBC_NDEN
 790			| AT_XDMAC_MBR_UBC_NSEN
 791			| period_len >> at_xdmac_get_dwidth(desc->lld.mbr_cfg);
 792
 793		dev_dbg(chan2dev(chan),
 794			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
 795			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
 796
 797		/* Chain lld. */
 798		if (prev)
 799			at_xdmac_queue_desc(chan, prev, desc);
 800
 801		prev = desc;
 802		if (!first)
 803			first = desc;
 804
 805		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
 806			 __func__, desc, first);
 807		list_add_tail(&desc->desc_node, &first->descs_list);
 808	}
 809
 810	at_xdmac_queue_desc(chan, prev, first);
 811	first->tx_dma_desc.flags = flags;
 812	first->xfer_size = buf_len;
 813	first->direction = direction;
 814
 815	return &first->tx_dma_desc;
 816}
 817
 818static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr)
 819{
 820	u32 width;
 821
 822	/*
 823	 * Check address alignment to select the greater data width we
 824	 * can use.
 825	 *
 826	 * Some XDMAC implementations don't provide dword transfer, in
 827	 * this case selecting dword has the same behavior as
 828	 * selecting word transfers.
 829	 */
 830	if (!(addr & 7)) {
 831		width = AT_XDMAC_CC_DWIDTH_DWORD;
 832		dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__);
 833	} else if (!(addr & 3)) {
 834		width = AT_XDMAC_CC_DWIDTH_WORD;
 835		dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__);
 836	} else if (!(addr & 1)) {
 837		width = AT_XDMAC_CC_DWIDTH_HALFWORD;
 838		dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__);
 839	} else {
 840		width = AT_XDMAC_CC_DWIDTH_BYTE;
 841		dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__);
 842	}
 843
 844	return width;
 845}
 846
 847static struct at_xdmac_desc *
 848at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
 849				struct at_xdmac_chan *atchan,
 850				struct at_xdmac_desc *prev,
 851				dma_addr_t src, dma_addr_t dst,
 852				struct dma_interleaved_template *xt,
 853				struct data_chunk *chunk)
 854{
 855	struct at_xdmac_desc	*desc;
 856	u32			dwidth;
 857	unsigned long		flags;
 858	size_t			ublen;
 859	/*
 860	 * WARNING: The channel configuration is set here since there is no
 861	 * dmaengine_slave_config call in this case. Moreover we don't know the
 862	 * direction, it involves we can't dynamically set the source and dest
 863	 * interface so we have to use the same one. Only interface 0 allows EBI
 864	 * access. Hopefully we can access DDR through both ports (at least on
 865	 * SAMA5D4x), so we can use the same interface for source and dest,
 866	 * that solves the fact we don't know the direction.
 867	 * ERRATA: Even if useless for memory transfers, the PERID has to not
 868	 * match the one of another channel. If not, it could lead to spurious
 869	 * flag status.
 
 
 
 
 870	 */
 871	u32			chan_cc = AT_XDMAC_CC_PERID(0x3f)
 872					| AT_XDMAC_CC_DIF(0)
 873					| AT_XDMAC_CC_SIF(0)
 874					| AT_XDMAC_CC_MBSIZE_SIXTEEN
 875					| AT_XDMAC_CC_TYPE_MEM_TRAN;
 876
 877	dwidth = at_xdmac_align_width(chan, src | dst | chunk->size);
 878	if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
 879		dev_dbg(chan2dev(chan),
 880			"%s: chunk too big (%d, max size %lu)...\n",
 881			__func__, chunk->size,
 882			AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth);
 883		return NULL;
 884	}
 885
 886	if (prev)
 887		dev_dbg(chan2dev(chan),
 888			"Adding items at the end of desc 0x%p\n", prev);
 889
 890	if (xt->src_inc) {
 891		if (xt->src_sgl)
 892			chan_cc |=  AT_XDMAC_CC_SAM_UBS_AM;
 893		else
 894			chan_cc |=  AT_XDMAC_CC_SAM_INCREMENTED_AM;
 895	}
 896
 897	if (xt->dst_inc) {
 898		if (xt->dst_sgl)
 899			chan_cc |=  AT_XDMAC_CC_DAM_UBS_AM;
 900		else
 901			chan_cc |=  AT_XDMAC_CC_DAM_INCREMENTED_AM;
 902	}
 903
 904	spin_lock_irqsave(&atchan->lock, flags);
 905	desc = at_xdmac_get_desc(atchan);
 906	spin_unlock_irqrestore(&atchan->lock, flags);
 907	if (!desc) {
 908		dev_err(chan2dev(chan), "can't get descriptor\n");
 909		return NULL;
 910	}
 911
 912	chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
 913
 914	ublen = chunk->size >> dwidth;
 915
 916	desc->lld.mbr_sa = src;
 917	desc->lld.mbr_da = dst;
 918	desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
 919	desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
 920
 921	desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
 922		| AT_XDMAC_MBR_UBC_NDEN
 923		| AT_XDMAC_MBR_UBC_NSEN
 924		| ublen;
 925	desc->lld.mbr_cfg = chan_cc;
 926
 927	dev_dbg(chan2dev(chan),
 928		"%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
 929		__func__, &desc->lld.mbr_sa, &desc->lld.mbr_da,
 930		desc->lld.mbr_ubc, desc->lld.mbr_cfg);
 931
 932	/* Chain lld. */
 933	if (prev)
 934		at_xdmac_queue_desc(chan, prev, desc);
 935
 936	return desc;
 937}
 938
 939static struct dma_async_tx_descriptor *
 940at_xdmac_prep_interleaved(struct dma_chan *chan,
 941			  struct dma_interleaved_template *xt,
 942			  unsigned long flags)
 943{
 944	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 945	struct at_xdmac_desc	*prev = NULL, *first = NULL;
 946	dma_addr_t		dst_addr, src_addr;
 947	size_t			src_skip = 0, dst_skip = 0, len = 0;
 948	struct data_chunk	*chunk;
 949	int			i;
 950
 951	if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
 952		return NULL;
 953
 954	/*
 955	 * TODO: Handle the case where we have to repeat a chain of
 956	 * descriptors...
 957	 */
 958	if ((xt->numf > 1) && (xt->frame_size > 1))
 959		return NULL;
 960
 961	dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%d, frame_size=%d, flags=0x%lx\n",
 962		__func__, &xt->src_start, &xt->dst_start,	xt->numf,
 963		xt->frame_size, flags);
 964
 965	src_addr = xt->src_start;
 966	dst_addr = xt->dst_start;
 967
 968	if (xt->numf > 1) {
 969		first = at_xdmac_interleaved_queue_desc(chan, atchan,
 970							NULL,
 971							src_addr, dst_addr,
 972							xt, xt->sgl);
 
 
 973
 974		/* Length of the block is (BLEN+1) microblocks. */
 975		for (i = 0; i < xt->numf - 1; i++)
 976			at_xdmac_increment_block_count(chan, first);
 977
 978		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
 979			__func__, first, first);
 980		list_add_tail(&first->desc_node, &first->descs_list);
 981	} else {
 982		for (i = 0; i < xt->frame_size; i++) {
 983			size_t src_icg = 0, dst_icg = 0;
 984			struct at_xdmac_desc *desc;
 985
 986			chunk = xt->sgl + i;
 987
 988			dst_icg = dmaengine_get_dst_icg(xt, chunk);
 989			src_icg = dmaengine_get_src_icg(xt, chunk);
 990
 991			src_skip = chunk->size + src_icg;
 992			dst_skip = chunk->size + dst_icg;
 993
 994			dev_dbg(chan2dev(chan),
 995				"%s: chunk size=%d, src icg=%d, dst icg=%d\n",
 996				__func__, chunk->size, src_icg, dst_icg);
 997
 998			desc = at_xdmac_interleaved_queue_desc(chan, atchan,
 999							       prev,
1000							       src_addr, dst_addr,
1001							       xt, chunk);
1002			if (!desc) {
1003				list_splice_init(&first->descs_list,
1004						 &atchan->free_descs_list);
 
1005				return NULL;
1006			}
1007
1008			if (!first)
1009				first = desc;
1010
1011			dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1012				__func__, desc, first);
1013			list_add_tail(&desc->desc_node, &first->descs_list);
1014
1015			if (xt->src_sgl)
1016				src_addr += src_skip;
1017
1018			if (xt->dst_sgl)
1019				dst_addr += dst_skip;
1020
1021			len += chunk->size;
1022			prev = desc;
1023		}
1024	}
1025
1026	first->tx_dma_desc.cookie = -EBUSY;
1027	first->tx_dma_desc.flags = flags;
1028	first->xfer_size = len;
1029
1030	return &first->tx_dma_desc;
1031}
1032
1033static struct dma_async_tx_descriptor *
1034at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1035			 size_t len, unsigned long flags)
1036{
1037	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1038	struct at_xdmac_desc	*first = NULL, *prev = NULL;
1039	size_t			remaining_size = len, xfer_size = 0, ublen;
1040	dma_addr_t		src_addr = src, dst_addr = dest;
1041	u32			dwidth;
1042	/*
1043	 * WARNING: We don't know the direction, it involves we can't
1044	 * dynamically set the source and dest interface so we have to use the
1045	 * same one. Only interface 0 allows EBI access. Hopefully we can
1046	 * access DDR through both ports (at least on SAMA5D4x), so we can use
1047	 * the same interface for source and dest, that solves the fact we
1048	 * don't know the direction.
1049	 * ERRATA: Even if useless for memory transfers, the PERID has to not
1050	 * match the one of another channel. If not, it could lead to spurious
1051	 * flag status.
 
 
 
 
1052	 */
1053	u32			chan_cc = AT_XDMAC_CC_PERID(0x3f)
1054					| AT_XDMAC_CC_DAM_INCREMENTED_AM
1055					| AT_XDMAC_CC_SAM_INCREMENTED_AM
1056					| AT_XDMAC_CC_DIF(0)
1057					| AT_XDMAC_CC_SIF(0)
1058					| AT_XDMAC_CC_MBSIZE_SIXTEEN
1059					| AT_XDMAC_CC_TYPE_MEM_TRAN;
1060	unsigned long		irqflags;
1061
1062	dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n",
1063		__func__, &src, &dest, len, flags);
1064
1065	if (unlikely(!len))
1066		return NULL;
1067
1068	dwidth = at_xdmac_align_width(chan, src_addr | dst_addr);
1069
1070	/* Prepare descriptors. */
1071	while (remaining_size) {
1072		struct at_xdmac_desc	*desc = NULL;
1073
1074		dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size);
1075
1076		spin_lock_irqsave(&atchan->lock, irqflags);
1077		desc = at_xdmac_get_desc(atchan);
1078		spin_unlock_irqrestore(&atchan->lock, irqflags);
1079		if (!desc) {
1080			dev_err(chan2dev(chan), "can't get descriptor\n");
1081			if (first)
1082				list_splice_init(&first->descs_list, &atchan->free_descs_list);
 
1083			return NULL;
1084		}
1085
1086		/* Update src and dest addresses. */
1087		src_addr += xfer_size;
1088		dst_addr += xfer_size;
1089
1090		if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)
1091			xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth;
1092		else
1093			xfer_size = remaining_size;
1094
1095		dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size);
1096
1097		/* Check remaining length and change data width if needed. */
1098		dwidth = at_xdmac_align_width(chan,
1099					      src_addr | dst_addr | xfer_size);
1100		chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK;
1101		chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1102
1103		ublen = xfer_size >> dwidth;
1104		remaining_size -= xfer_size;
1105
1106		desc->lld.mbr_sa = src_addr;
1107		desc->lld.mbr_da = dst_addr;
1108		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2
1109			| AT_XDMAC_MBR_UBC_NDEN
1110			| AT_XDMAC_MBR_UBC_NSEN
1111			| ublen;
1112		desc->lld.mbr_cfg = chan_cc;
1113
1114		dev_dbg(chan2dev(chan),
1115			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1116			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1117
1118		/* Chain lld. */
1119		if (prev)
1120			at_xdmac_queue_desc(chan, prev, desc);
1121
1122		prev = desc;
1123		if (!first)
1124			first = desc;
1125
1126		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1127			 __func__, desc, first);
1128		list_add_tail(&desc->desc_node, &first->descs_list);
1129	}
1130
1131	first->tx_dma_desc.flags = flags;
1132	first->xfer_size = len;
1133
1134	return &first->tx_dma_desc;
1135}
1136
1137static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
1138							 struct at_xdmac_chan *atchan,
1139							 dma_addr_t dst_addr,
1140							 size_t len,
1141							 int value)
1142{
1143	struct at_xdmac_desc	*desc;
1144	unsigned long		flags;
1145	size_t			ublen;
1146	u32			dwidth;
 
1147	/*
1148	 * WARNING: The channel configuration is set here since there is no
1149	 * dmaengine_slave_config call in this case. Moreover we don't know the
1150	 * direction, it involves we can't dynamically set the source and dest
1151	 * interface so we have to use the same one. Only interface 0 allows EBI
1152	 * access. Hopefully we can access DDR through both ports (at least on
1153	 * SAMA5D4x), so we can use the same interface for source and dest,
1154	 * that solves the fact we don't know the direction.
1155	 * ERRATA: Even if useless for memory transfers, the PERID has to not
1156	 * match the one of another channel. If not, it could lead to spurious
1157	 * flag status.
 
 
 
 
1158	 */
1159	u32			chan_cc = AT_XDMAC_CC_PERID(0x3f)
1160					| AT_XDMAC_CC_DAM_UBS_AM
1161					| AT_XDMAC_CC_SAM_INCREMENTED_AM
1162					| AT_XDMAC_CC_DIF(0)
1163					| AT_XDMAC_CC_SIF(0)
1164					| AT_XDMAC_CC_MBSIZE_SIXTEEN
1165					| AT_XDMAC_CC_MEMSET_HW_MODE
1166					| AT_XDMAC_CC_TYPE_MEM_TRAN;
1167
1168	dwidth = at_xdmac_align_width(chan, dst_addr);
1169
1170	if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1171		dev_err(chan2dev(chan),
1172			"%s: Transfer too large, aborting...\n",
1173			__func__);
1174		return NULL;
1175	}
1176
1177	spin_lock_irqsave(&atchan->lock, flags);
1178	desc = at_xdmac_get_desc(atchan);
1179	spin_unlock_irqrestore(&atchan->lock, flags);
1180	if (!desc) {
1181		dev_err(chan2dev(chan), "can't get descriptor\n");
1182		return NULL;
1183	}
1184
1185	chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1186
 
 
 
1187	ublen = len >> dwidth;
1188
1189	desc->lld.mbr_da = dst_addr;
1190	desc->lld.mbr_ds = value;
 
 
 
1191	desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1192		| AT_XDMAC_MBR_UBC_NDEN
1193		| AT_XDMAC_MBR_UBC_NSEN
1194		| ublen;
1195	desc->lld.mbr_cfg = chan_cc;
1196
1197	dev_dbg(chan2dev(chan),
1198		"%s: lld: mbr_da=%pad, mbr_ds=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1199		__func__, &desc->lld.mbr_da, &desc->lld.mbr_ds, desc->lld.mbr_ubc,
1200		desc->lld.mbr_cfg);
1201
1202	return desc;
1203}
1204
1205struct dma_async_tx_descriptor *
1206at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
1207			 size_t len, unsigned long flags)
1208{
1209	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1210	struct at_xdmac_desc	*desc;
1211
1212	dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
1213		__func__, &dest, len, value, flags);
1214
1215	if (unlikely(!len))
1216		return NULL;
1217
1218	desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value);
1219	list_add_tail(&desc->desc_node, &desc->descs_list);
1220
1221	desc->tx_dma_desc.cookie = -EBUSY;
1222	desc->tx_dma_desc.flags = flags;
1223	desc->xfer_size = len;
1224
1225	return &desc->tx_dma_desc;
1226}
1227
1228static struct dma_async_tx_descriptor *
1229at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
1230			    unsigned int sg_len, int value,
1231			    unsigned long flags)
1232{
1233	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1234	struct at_xdmac_desc	*desc, *pdesc = NULL,
1235				*ppdesc = NULL, *first = NULL;
1236	struct scatterlist	*sg, *psg = NULL, *ppsg = NULL;
1237	size_t			stride = 0, pstride = 0, len = 0;
1238	int			i;
1239
1240	if (!sgl)
1241		return NULL;
1242
1243	dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n",
1244		__func__, sg_len, value, flags);
1245
1246	/* Prepare descriptors. */
1247	for_each_sg(sgl, sg, sg_len, i) {
1248		dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
1249			__func__, &sg_dma_address(sg), sg_dma_len(sg),
1250			value, flags);
1251		desc = at_xdmac_memset_create_desc(chan, atchan,
1252						   sg_dma_address(sg),
1253						   sg_dma_len(sg),
1254						   value);
1255		if (!desc && first)
1256			list_splice_init(&first->descs_list,
1257					 &atchan->free_descs_list);
1258
1259		if (!first)
1260			first = desc;
1261
1262		/* Update our strides */
1263		pstride = stride;
1264		if (psg)
1265			stride = sg_dma_address(sg) -
1266				(sg_dma_address(psg) + sg_dma_len(psg));
1267
1268		/*
1269		 * The scatterlist API gives us only the address and
1270		 * length of each elements.
1271		 *
1272		 * Unfortunately, we don't have the stride, which we
1273		 * will need to compute.
1274		 *
1275		 * That make us end up in a situation like this one:
1276		 *    len    stride    len    stride    len
1277		 * +-------+        +-------+        +-------+
1278		 * |  N-2  |        |  N-1  |        |   N   |
1279		 * +-------+        +-------+        +-------+
1280		 *
1281		 * We need all these three elements (N-2, N-1 and N)
1282		 * to actually take the decision on whether we need to
1283		 * queue N-1 or reuse N-2.
1284		 *
1285		 * We will only consider N if it is the last element.
1286		 */
1287		if (ppdesc && pdesc) {
1288			if ((stride == pstride) &&
1289			    (sg_dma_len(ppsg) == sg_dma_len(psg))) {
1290				dev_dbg(chan2dev(chan),
1291					"%s: desc 0x%p can be merged with desc 0x%p\n",
1292					__func__, pdesc, ppdesc);
1293
1294				/*
1295				 * Increment the block count of the
1296				 * N-2 descriptor
1297				 */
1298				at_xdmac_increment_block_count(chan, ppdesc);
1299				ppdesc->lld.mbr_dus = stride;
1300
1301				/*
1302				 * Put back the N-1 descriptor in the
1303				 * free descriptor list
1304				 */
1305				list_add_tail(&pdesc->desc_node,
1306					      &atchan->free_descs_list);
1307
1308				/*
1309				 * Make our N-1 descriptor pointer
1310				 * point to the N-2 since they were
1311				 * actually merged.
1312				 */
1313				pdesc = ppdesc;
1314
1315			/*
1316			 * Rule out the case where we don't have
1317			 * pstride computed yet (our second sg
1318			 * element)
1319			 *
1320			 * We also want to catch the case where there
1321			 * would be a negative stride,
1322			 */
1323			} else if (pstride ||
1324				   sg_dma_address(sg) < sg_dma_address(psg)) {
1325				/*
1326				 * Queue the N-1 descriptor after the
1327				 * N-2
1328				 */
1329				at_xdmac_queue_desc(chan, ppdesc, pdesc);
1330
1331				/*
1332				 * Add the N-1 descriptor to the list
1333				 * of the descriptors used for this
1334				 * transfer
1335				 */
1336				list_add_tail(&desc->desc_node,
1337					      &first->descs_list);
1338				dev_dbg(chan2dev(chan),
1339					"%s: add desc 0x%p to descs_list 0x%p\n",
1340					__func__, desc, first);
1341			}
1342		}
1343
1344		/*
1345		 * If we are the last element, just see if we have the
1346		 * same size than the previous element.
1347		 *
1348		 * If so, we can merge it with the previous descriptor
1349		 * since we don't care about the stride anymore.
1350		 */
1351		if ((i == (sg_len - 1)) &&
1352		    sg_dma_len(psg) == sg_dma_len(sg)) {
1353			dev_dbg(chan2dev(chan),
1354				"%s: desc 0x%p can be merged with desc 0x%p\n",
1355				__func__, desc, pdesc);
1356
1357			/*
1358			 * Increment the block count of the N-1
1359			 * descriptor
1360			 */
1361			at_xdmac_increment_block_count(chan, pdesc);
1362			pdesc->lld.mbr_dus = stride;
1363
1364			/*
1365			 * Put back the N descriptor in the free
1366			 * descriptor list
1367			 */
1368			list_add_tail(&desc->desc_node,
1369				      &atchan->free_descs_list);
1370		}
1371
1372		/* Update our descriptors */
1373		ppdesc = pdesc;
1374		pdesc = desc;
1375
1376		/* Update our scatter pointers */
1377		ppsg = psg;
1378		psg = sg;
1379
1380		len += sg_dma_len(sg);
1381	}
1382
1383	first->tx_dma_desc.cookie = -EBUSY;
1384	first->tx_dma_desc.flags = flags;
1385	first->xfer_size = len;
1386
1387	return &first->tx_dma_desc;
1388}
1389
1390static enum dma_status
1391at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1392		struct dma_tx_state *txstate)
1393{
1394	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1395	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1396	struct at_xdmac_desc	*desc, *_desc;
1397	struct list_head	*descs_list;
1398	enum dma_status		ret;
1399	int			residue, retry;
1400	u32			cur_nda, check_nda, cur_ubc, mask, value;
1401	u8			dwidth = 0;
1402	unsigned long		flags;
 
1403
1404	ret = dma_cookie_status(chan, cookie, txstate);
1405	if (ret == DMA_COMPLETE)
1406		return ret;
1407
1408	if (!txstate)
1409		return ret;
 
1410
1411	spin_lock_irqsave(&atchan->lock, flags);
1412
1413	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
1414
1415	/*
1416	 * If the transfer has not been started yet, don't need to compute the
1417	 * residue, it's the transfer length.
1418	 */
1419	if (!desc->active_xfer) {
1420		dma_set_residue(txstate, desc->xfer_size);
1421		goto spin_unlock;
1422	}
1423
1424	residue = desc->xfer_size;
1425	/*
1426	 * Flush FIFO: only relevant when the transfer is source peripheral
1427	 * synchronized.
 
 
 
 
 
 
 
 
 
1428	 */
1429	mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC;
1430	value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM;
1431	if ((desc->lld.mbr_cfg & mask) == value) {
1432		at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask);
1433		while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1434			cpu_relax();
1435	}
1436
1437	/*
1438	 * When processing the residue, we need to read two registers but we
1439	 * can't do it in an atomic way. AT_XDMAC_CNDA is used to find where
1440	 * we stand in the descriptor list and AT_XDMAC_CUBC is used
1441	 * to know how many data are remaining for the current descriptor.
1442	 * Since the dma channel is not paused to not loose data, between the
1443	 * AT_XDMAC_CNDA and AT_XDMAC_CUBC read, we may have change of
1444	 * descriptor.
1445	 * For that reason, after reading AT_XDMAC_CUBC, we check if we are
1446	 * still using the same descriptor by reading a second time
1447	 * AT_XDMAC_CNDA. If AT_XDMAC_CNDA has changed, it means we have to
1448	 * read again AT_XDMAC_CUBC.
 
 
 
 
 
 
 
 
 
 
 
1449	 * Memory barriers are used to ensure the read order of the registers.
1450	 * A max number of retries is set because unlikely it can never ends if
1451	 * we are transferring a lot of data with small buffers.
1452	 */
1453	cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1454	rmb();
1455	cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
1456	for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
 
 
 
 
 
 
 
1457		rmb();
1458		check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1459
1460		if (likely(cur_nda == check_nda))
1461			break;
1462
1463		cur_nda = check_nda;
1464		rmb();
1465		cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
1466	}
1467
1468	if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
1469		ret = DMA_ERROR;
1470		goto spin_unlock;
1471	}
1472
1473	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
1474	 * Remove size of all microblocks already transferred and the current
1475	 * one. Then add the remaining size to transfer of the current
1476	 * microblock.
1477	 */
1478	descs_list = &desc->descs_list;
1479	list_for_each_entry_safe(desc, _desc, descs_list, desc_node) {
1480		dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg);
1481		residue -= (desc->lld.mbr_ubc & 0xffffff) << dwidth;
1482		if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda)
 
1483			break;
 
1484	}
1485	residue += cur_ubc << dwidth;
1486
1487	dma_set_residue(txstate, residue);
1488
1489	dev_dbg(chan2dev(chan),
1490		 "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n",
1491		 __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
1492
1493spin_unlock:
1494	spin_unlock_irqrestore(&atchan->lock, flags);
 
 
1495	return ret;
1496}
1497
1498/* Call must be protected by lock. */
1499static void at_xdmac_remove_xfer(struct at_xdmac_chan *atchan,
1500				    struct at_xdmac_desc *desc)
1501{
1502	dev_dbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1503
1504	/*
1505	 * Remove the transfer from the transfer list then move the transfer
1506	 * descriptors into the free descriptors list.
1507	 */
1508	list_del(&desc->xfer_node);
1509	list_splice_init(&desc->descs_list, &atchan->free_descs_list);
1510}
1511
1512static void at_xdmac_advance_work(struct at_xdmac_chan *atchan)
1513{
1514	struct at_xdmac_desc	*desc;
1515	unsigned long		flags;
1516
1517	spin_lock_irqsave(&atchan->lock, flags);
1518
1519	/*
1520	 * If channel is enabled, do nothing, advance_work will be triggered
1521	 * after the interruption.
1522	 */
1523	if (!at_xdmac_chan_is_enabled(atchan) && !list_empty(&atchan->xfers_list)) {
1524		desc = list_first_entry(&atchan->xfers_list,
1525					struct at_xdmac_desc,
1526					xfer_node);
1527		dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1528		if (!desc->active_xfer)
1529			at_xdmac_start_xfer(atchan, desc);
1530	}
1531
1532	spin_unlock_irqrestore(&atchan->lock, flags);
 
 
 
 
1533}
1534
1535static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
1536{
1537	struct at_xdmac_desc		*desc;
1538	struct dma_async_tx_descriptor	*txd;
1539
1540	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
 
 
 
 
 
 
 
 
 
1541	txd = &desc->tx_dma_desc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1542
1543	if (txd->callback && (txd->flags & DMA_PREP_INTERRUPT))
1544		txd->callback(txd->callback_param);
 
 
1545}
1546
1547static void at_xdmac_tasklet(unsigned long data)
1548{
1549	struct at_xdmac_chan	*atchan = (struct at_xdmac_chan *)data;
 
1550	struct at_xdmac_desc	*desc;
 
1551	u32			error_mask;
1552
1553	dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08lx\n",
1554		 __func__, atchan->status);
1555
1556	error_mask = AT_XDMAC_CIS_RBEIS
1557		     | AT_XDMAC_CIS_WBEIS
1558		     | AT_XDMAC_CIS_ROIS;
1559
1560	if (at_xdmac_chan_is_cyclic(atchan)) {
1561		at_xdmac_handle_cyclic(atchan);
1562	} else if ((atchan->status & AT_XDMAC_CIS_LIS)
1563		   || (atchan->status & error_mask)) {
1564		struct dma_async_tx_descriptor  *txd;
1565
1566		if (atchan->status & AT_XDMAC_CIS_RBEIS)
1567			dev_err(chan2dev(&atchan->chan), "read bus error!!!");
1568		if (atchan->status & AT_XDMAC_CIS_WBEIS)
1569			dev_err(chan2dev(&atchan->chan), "write bus error!!!");
1570		if (atchan->status & AT_XDMAC_CIS_ROIS)
1571			dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
1572
1573		spin_lock_bh(&atchan->lock);
1574		desc = list_first_entry(&atchan->xfers_list,
1575					struct at_xdmac_desc,
1576					xfer_node);
1577		dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1578		BUG_ON(!desc->active_xfer);
1579
1580		txd = &desc->tx_dma_desc;
1581
1582		at_xdmac_remove_xfer(atchan, desc);
1583		spin_unlock_bh(&atchan->lock);
1584
1585		if (!at_xdmac_chan_is_cyclic(atchan)) {
1586			dma_cookie_complete(txd);
1587			if (txd->callback && (txd->flags & DMA_PREP_INTERRUPT))
1588				txd->callback(txd->callback_param);
1589		}
1590
1591		dma_run_dependencies(txd);
 
1592
1593		at_xdmac_advance_work(atchan);
 
 
 
1594	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1595}
1596
1597static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
1598{
1599	struct at_xdmac		*atxdmac = (struct at_xdmac *)dev_id;
1600	struct at_xdmac_chan	*atchan;
1601	u32			imr, status, pending;
1602	u32			chan_imr, chan_status;
1603	int			i, ret = IRQ_NONE;
1604
1605	do {
1606		imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1607		status = at_xdmac_read(atxdmac, AT_XDMAC_GIS);
1608		pending = status & imr;
1609
1610		dev_vdbg(atxdmac->dma.dev,
1611			 "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n",
1612			 __func__, status, imr, pending);
1613
1614		if (!pending)
1615			break;
1616
1617		/* We have to find which channel has generated the interrupt. */
1618		for (i = 0; i < atxdmac->dma.chancnt; i++) {
1619			if (!((1 << i) & pending))
1620				continue;
1621
1622			atchan = &atxdmac->chan[i];
1623			chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1624			chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
1625			atchan->status = chan_status & chan_imr;
1626			dev_vdbg(atxdmac->dma.dev,
1627				 "%s: chan%d: imr=0x%x, status=0x%x\n",
1628				 __func__, i, chan_imr, chan_status);
1629			dev_vdbg(chan2dev(&atchan->chan),
1630				 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
1631				 __func__,
1632				 at_xdmac_chan_read(atchan, AT_XDMAC_CC),
1633				 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
1634				 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
1635				 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
1636				 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
1637				 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
1638
1639			if (atchan->status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
1640				at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1641
1642			tasklet_schedule(&atchan->tasklet);
1643			ret = IRQ_HANDLED;
1644		}
1645
1646	} while (pending);
1647
1648	return ret;
1649}
1650
1651static void at_xdmac_issue_pending(struct dma_chan *chan)
1652{
1653	struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
 
1654
1655	dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__);
1656
1657	if (!at_xdmac_chan_is_cyclic(atchan))
1658		at_xdmac_advance_work(atchan);
 
1659
1660	return;
1661}
1662
1663static int at_xdmac_device_config(struct dma_chan *chan,
1664				  struct dma_slave_config *config)
1665{
1666	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1667	int ret;
1668	unsigned long		flags;
1669
1670	dev_dbg(chan2dev(chan), "%s\n", __func__);
1671
1672	spin_lock_irqsave(&atchan->lock, flags);
1673	ret = at_xdmac_set_slave_config(chan, config);
1674	spin_unlock_irqrestore(&atchan->lock, flags);
1675
1676	return ret;
1677}
1678
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1679static int at_xdmac_device_pause(struct dma_chan *chan)
1680{
1681	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1682	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1683	unsigned long		flags;
 
1684
1685	dev_dbg(chan2dev(chan), "%s\n", __func__);
1686
1687	if (test_and_set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status))
1688		return 0;
1689
 
 
 
 
1690	spin_lock_irqsave(&atchan->lock, flags);
1691	at_xdmac_write(atxdmac, AT_XDMAC_GRWS, atchan->mask);
1692	while (at_xdmac_chan_read(atchan, AT_XDMAC_CC)
1693	       & (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP))
1694		cpu_relax();
 
1695	spin_unlock_irqrestore(&atchan->lock, flags);
1696
 
 
 
1697	return 0;
1698}
1699
 
 
 
 
 
 
 
 
 
 
 
1700static int at_xdmac_device_resume(struct dma_chan *chan)
1701{
1702	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1703	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1704	unsigned long		flags;
 
1705
1706	dev_dbg(chan2dev(chan), "%s\n", __func__);
1707
 
 
 
 
1708	spin_lock_irqsave(&atchan->lock, flags);
1709	if (!at_xdmac_chan_is_paused(atchan)) {
1710		spin_unlock_irqrestore(&atchan->lock, flags);
1711		return 0;
1712	}
 
 
 
1713
1714	at_xdmac_write(atxdmac, AT_XDMAC_GRWR, atchan->mask);
1715	clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
 
 
1716	spin_unlock_irqrestore(&atchan->lock, flags);
 
 
1717
1718	return 0;
1719}
1720
1721static int at_xdmac_device_terminate_all(struct dma_chan *chan)
1722{
1723	struct at_xdmac_desc	*desc, *_desc;
1724	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1725	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1726	unsigned long		flags;
 
1727
1728	dev_dbg(chan2dev(chan), "%s\n", __func__);
1729
 
 
 
 
1730	spin_lock_irqsave(&atchan->lock, flags);
1731	at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1732	while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1733		cpu_relax();
1734
1735	/* Cancel all pending transfers. */
1736	list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node)
1737		at_xdmac_remove_xfer(atchan, desc);
 
 
 
 
 
 
 
 
 
 
 
 
1738
1739	clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
1740	clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
1741	spin_unlock_irqrestore(&atchan->lock, flags);
1742
 
 
 
1743	return 0;
1744}
1745
1746static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
1747{
1748	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1749	struct at_xdmac_desc	*desc;
1750	int			i;
1751	unsigned long		flags;
1752
1753	spin_lock_irqsave(&atchan->lock, flags);
1754
1755	if (at_xdmac_chan_is_enabled(atchan)) {
1756		dev_err(chan2dev(chan),
1757			"can't allocate channel resources (channel enabled)\n");
1758		i = -EIO;
1759		goto spin_unlock;
1760	}
1761
1762	if (!list_empty(&atchan->free_descs_list)) {
1763		dev_err(chan2dev(chan),
1764			"can't allocate channel resources (channel not free from a previous use)\n");
1765		i = -EIO;
1766		goto spin_unlock;
1767	}
1768
1769	for (i = 0; i < init_nr_desc_per_channel; i++) {
1770		desc = at_xdmac_alloc_desc(chan, GFP_ATOMIC);
1771		if (!desc) {
 
 
 
 
 
1772			dev_warn(chan2dev(chan),
1773				"only %d descriptors have been allocated\n", i);
1774			break;
1775		}
1776		list_add_tail(&desc->desc_node, &atchan->free_descs_list);
1777	}
1778
1779	dma_cookie_init(chan);
1780
1781	dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
1782
1783spin_unlock:
1784	spin_unlock_irqrestore(&atchan->lock, flags);
1785	return i;
1786}
1787
1788static void at_xdmac_free_chan_resources(struct dma_chan *chan)
1789{
1790	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1791	struct at_xdmac		*atxdmac = to_at_xdmac(chan->device);
1792	struct at_xdmac_desc	*desc, *_desc;
1793
1794	list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) {
1795		dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc);
1796		list_del(&desc->desc_node);
1797		dma_pool_free(atxdmac->at_xdmac_desc_pool, desc, desc->tx_dma_desc.phys);
1798	}
1799
1800	return;
1801}
1802
1803#ifdef CONFIG_PM
1804static int atmel_xdmac_prepare(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1805{
1806	struct platform_device	*pdev = to_platform_device(dev);
1807	struct at_xdmac		*atxdmac = platform_get_drvdata(pdev);
1808	struct dma_chan		*chan, *_chan;
1809
1810	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1811		struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1812
1813		/* Wait for transfer completion, except in cyclic case. */
1814		if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan))
1815			return -EAGAIN;
1816	}
1817	return 0;
1818}
1819#else
1820#	define atmel_xdmac_prepare NULL
1821#endif
1822
1823#ifdef CONFIG_PM_SLEEP
1824static int atmel_xdmac_suspend(struct device *dev)
1825{
1826	struct platform_device	*pdev = to_platform_device(dev);
1827	struct at_xdmac		*atxdmac = platform_get_drvdata(pdev);
1828	struct dma_chan		*chan, *_chan;
 
 
 
 
 
1829
1830	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1831		struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1832
1833		atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
1834		if (at_xdmac_chan_is_cyclic(atchan)) {
1835			if (!at_xdmac_chan_is_paused(atchan))
1836				at_xdmac_device_pause(chan);
 
 
 
 
1837			atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1838			atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
1839			atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC);
1840		}
1841	}
1842	atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
 
1843
1844	at_xdmac_off(atxdmac);
 
 
1845	clk_disable_unprepare(atxdmac->clk);
 
1846	return 0;
1847}
1848
1849static int atmel_xdmac_resume(struct device *dev)
1850{
1851	struct platform_device	*pdev = to_platform_device(dev);
1852	struct at_xdmac		*atxdmac = platform_get_drvdata(pdev);
1853	struct at_xdmac_chan	*atchan;
1854	struct dma_chan		*chan, *_chan;
1855	int			i;
 
 
 
 
 
 
 
1856
1857	clk_prepare_enable(atxdmac->clk);
1858
1859	/* Clear pending interrupts. */
1860	for (i = 0; i < atxdmac->dma.chancnt; i++) {
1861		atchan = &atxdmac->chan[i];
1862		while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
1863			cpu_relax();
1864	}
1865
1866	at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim);
1867	at_xdmac_write(atxdmac, AT_XDMAC_GE, atxdmac->save_gs);
1868	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1869		atchan = to_at_xdmac_chan(chan);
 
1870		at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
1871		if (at_xdmac_chan_is_cyclic(atchan)) {
1872			if (at_xdmac_chan_is_paused(atchan))
1873				at_xdmac_device_resume(chan);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1874			at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
1875			at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
1876			at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim);
1877			wmb();
1878			at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
 
1879		}
1880	}
 
 
 
 
 
 
 
 
 
 
 
 
 
1881	return 0;
1882}
1883#endif /* CONFIG_PM_SLEEP */
 
 
 
 
 
 
1884
1885static int at_xdmac_probe(struct platform_device *pdev)
1886{
1887	struct resource	*res;
1888	struct at_xdmac	*atxdmac;
1889	int		irq, size, nr_channels, i, ret;
1890	void __iomem	*base;
1891	u32		reg;
1892
1893	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1894	if (!res)
1895		return -EINVAL;
1896
1897	irq = platform_get_irq(pdev, 0);
1898	if (irq < 0)
1899		return irq;
1900
1901	base = devm_ioremap_resource(&pdev->dev, res);
1902	if (IS_ERR(base))
1903		return PTR_ERR(base);
1904
1905	/*
1906	 * Read number of xdmac channels, read helper function can't be used
1907	 * since atxdmac is not yet allocated and we need to know the number
1908	 * of channels to do the allocation.
1909	 */
1910	reg = readl_relaxed(base + AT_XDMAC_GTYPE);
1911	nr_channels = AT_XDMAC_NB_CH(reg);
1912	if (nr_channels > AT_XDMAC_MAX_CHAN) {
1913		dev_err(&pdev->dev, "invalid number of channels (%u)\n",
1914			nr_channels);
1915		return -EINVAL;
1916	}
1917
1918	size = sizeof(*atxdmac);
1919	size += nr_channels * sizeof(struct at_xdmac_chan);
1920	atxdmac = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
1921	if (!atxdmac) {
1922		dev_err(&pdev->dev, "can't allocate at_xdmac structure\n");
1923		return -ENOMEM;
1924	}
1925
1926	atxdmac->regs = base;
1927	atxdmac->irq = irq;
 
 
 
 
 
1928
1929	atxdmac->clk = devm_clk_get(&pdev->dev, "dma_clk");
1930	if (IS_ERR(atxdmac->clk)) {
1931		dev_err(&pdev->dev, "can't get dma_clk\n");
1932		return PTR_ERR(atxdmac->clk);
1933	}
1934
1935	/* Do not use dev res to prevent races with tasklet */
1936	ret = request_irq(atxdmac->irq, at_xdmac_interrupt, 0, "at_xdmac", atxdmac);
1937	if (ret) {
1938		dev_err(&pdev->dev, "can't request irq\n");
1939		return ret;
1940	}
1941
1942	ret = clk_prepare_enable(atxdmac->clk);
1943	if (ret) {
1944		dev_err(&pdev->dev, "can't prepare or enable clock\n");
1945		goto err_free_irq;
1946	}
1947
1948	atxdmac->at_xdmac_desc_pool =
1949		dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
1950				sizeof(struct at_xdmac_desc), 4, 0);
1951	if (!atxdmac->at_xdmac_desc_pool) {
1952		dev_err(&pdev->dev, "no memory for descriptors dma pool\n");
1953		ret = -ENOMEM;
1954		goto err_clk_disable;
1955	}
1956
1957	dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask);
1958	dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask);
1959	dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask);
1960	dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask);
1961	dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask);
1962	dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask);
1963	/*
1964	 * Without DMA_PRIVATE the driver is not able to allocate more than
1965	 * one channel, second allocation fails in private_candidate.
1966	 */
1967	dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask);
1968	atxdmac->dma.dev				= &pdev->dev;
1969	atxdmac->dma.device_alloc_chan_resources	= at_xdmac_alloc_chan_resources;
1970	atxdmac->dma.device_free_chan_resources		= at_xdmac_free_chan_resources;
1971	atxdmac->dma.device_tx_status			= at_xdmac_tx_status;
1972	atxdmac->dma.device_issue_pending		= at_xdmac_issue_pending;
1973	atxdmac->dma.device_prep_dma_cyclic		= at_xdmac_prep_dma_cyclic;
1974	atxdmac->dma.device_prep_interleaved_dma	= at_xdmac_prep_interleaved;
1975	atxdmac->dma.device_prep_dma_memcpy		= at_xdmac_prep_dma_memcpy;
1976	atxdmac->dma.device_prep_dma_memset		= at_xdmac_prep_dma_memset;
1977	atxdmac->dma.device_prep_dma_memset_sg		= at_xdmac_prep_dma_memset_sg;
1978	atxdmac->dma.device_prep_slave_sg		= at_xdmac_prep_slave_sg;
1979	atxdmac->dma.device_config			= at_xdmac_device_config;
1980	atxdmac->dma.device_pause			= at_xdmac_device_pause;
1981	atxdmac->dma.device_resume			= at_xdmac_device_resume;
1982	atxdmac->dma.device_terminate_all		= at_xdmac_device_terminate_all;
1983	atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
1984	atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
1985	atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1986	atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1987
1988	/* Disable all chans and interrupts. */
1989	at_xdmac_off(atxdmac);
 
 
 
 
 
1990
1991	/* Init channels. */
1992	INIT_LIST_HEAD(&atxdmac->dma.channels);
 
 
 
 
1993	for (i = 0; i < nr_channels; i++) {
1994		struct at_xdmac_chan *atchan = &atxdmac->chan[i];
1995
1996		atchan->chan.device = &atxdmac->dma;
1997		list_add_tail(&atchan->chan.device_node,
1998			      &atxdmac->dma.channels);
1999
2000		atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, i);
2001		atchan->mask = 1 << i;
2002
2003		spin_lock_init(&atchan->lock);
2004		INIT_LIST_HEAD(&atchan->xfers_list);
2005		INIT_LIST_HEAD(&atchan->free_descs_list);
2006		tasklet_init(&atchan->tasklet, at_xdmac_tasklet,
2007			     (unsigned long)atchan);
2008
2009		/* Clear pending interrupts. */
2010		while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2011			cpu_relax();
2012	}
2013	platform_set_drvdata(pdev, atxdmac);
2014
2015	ret = dma_async_device_register(&atxdmac->dma);
2016	if (ret) {
2017		dev_err(&pdev->dev, "fail to register DMA engine device\n");
2018		goto err_clk_disable;
2019	}
2020
2021	ret = of_dma_controller_register(pdev->dev.of_node,
2022					 at_xdmac_xlate, atxdmac);
2023	if (ret) {
2024		dev_err(&pdev->dev, "could not register of dma controller\n");
2025		goto err_dma_unregister;
2026	}
2027
2028	dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n",
2029		 nr_channels, atxdmac->regs);
2030
 
 
 
 
 
2031	return 0;
2032
2033err_dma_unregister:
2034	dma_async_device_unregister(&atxdmac->dma);
 
 
 
 
 
2035err_clk_disable:
2036	clk_disable_unprepare(atxdmac->clk);
2037err_free_irq:
2038	free_irq(atxdmac->irq, atxdmac->dma.dev);
2039	return ret;
2040}
2041
2042static int at_xdmac_remove(struct platform_device *pdev)
2043{
2044	struct at_xdmac	*atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2045	int		i;
2046
2047	at_xdmac_off(atxdmac);
2048	of_dma_controller_free(pdev->dev.of_node);
2049	dma_async_device_unregister(&atxdmac->dma);
 
 
 
2050	clk_disable_unprepare(atxdmac->clk);
2051
2052	free_irq(atxdmac->irq, atxdmac->dma.dev);
2053
2054	for (i = 0; i < atxdmac->dma.chancnt; i++) {
2055		struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2056
2057		tasklet_kill(&atchan->tasklet);
2058		at_xdmac_free_chan_resources(&atchan->chan);
2059	}
2060
2061	return 0;
2062}
2063
2064static const struct dev_pm_ops atmel_xdmac_dev_pm_ops = {
2065	.prepare	= atmel_xdmac_prepare,
2066	SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume)
 
 
2067};
2068
2069static const struct of_device_id atmel_xdmac_dt_ids[] = {
2070	{
2071		.compatible = "atmel,sama5d4-dma",
 
 
 
 
2072	}, {
2073		/* sentinel */
2074	}
2075};
2076MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids);
2077
2078static struct platform_driver at_xdmac_driver = {
2079	.probe		= at_xdmac_probe,
2080	.remove		= at_xdmac_remove,
2081	.driver = {
2082		.name		= "at_xdmac",
2083		.of_match_table	= of_match_ptr(atmel_xdmac_dt_ids),
2084		.pm		= &atmel_xdmac_dev_pm_ops,
2085	}
2086};
2087
2088static int __init at_xdmac_init(void)
2089{
2090	return platform_driver_probe(&at_xdmac_driver, at_xdmac_probe);
2091}
2092subsys_initcall(at_xdmac_init);
 
 
 
 
 
 
2093
2094MODULE_DESCRIPTION("Atmel Extended DMA Controller driver");
2095MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
2096MODULE_LICENSE("GPL");