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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");
v5.14.15
   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
  25#include "dmaengine.h"
  26
  27/* Global registers */
  28#define AT_XDMAC_GTYPE		0x00	/* Global Type Register */
  29#define		AT_XDMAC_NB_CH(i)	(((i) & 0x1F) + 1)		/* Number of Channels Minus One */
  30#define		AT_XDMAC_FIFO_SZ(i)	(((i) >> 5) & 0x7FF)		/* Number of Bytes */
  31#define		AT_XDMAC_NB_REQ(i)	((((i) >> 16) & 0x3F) + 1)	/* Number of Peripheral Requests Minus One */
  32#define AT_XDMAC_GCFG		0x04	/* Global Configuration Register */
  33#define		AT_XDMAC_WRHP(i)		(((i) & 0xF) << 4)
  34#define		AT_XDMAC_WRMP(i)		(((i) & 0xF) << 8)
  35#define		AT_XDMAC_WRLP(i)		(((i) & 0xF) << 12)
  36#define		AT_XDMAC_RDHP(i)		(((i) & 0xF) << 16)
  37#define		AT_XDMAC_RDMP(i)		(((i) & 0xF) << 20)
  38#define		AT_XDMAC_RDLP(i)		(((i) & 0xF) << 24)
  39#define		AT_XDMAC_RDSG(i)		(((i) & 0xF) << 28)
  40#define AT_XDMAC_GCFG_M2M	(AT_XDMAC_RDLP(0xF) | AT_XDMAC_WRLP(0xF))
  41#define AT_XDMAC_GCFG_P2M	(AT_XDMAC_RDSG(0x1) | AT_XDMAC_RDHP(0x3) | \
  42				AT_XDMAC_WRHP(0x5))
  43#define AT_XDMAC_GWAC		0x08	/* Global Weighted Arbiter Configuration Register */
  44#define		AT_XDMAC_PW0(i)		(((i) & 0xF) << 0)
  45#define		AT_XDMAC_PW1(i)		(((i) & 0xF) << 4)
  46#define		AT_XDMAC_PW2(i)		(((i) & 0xF) << 8)
  47#define		AT_XDMAC_PW3(i)		(((i) & 0xF) << 12)
  48#define AT_XDMAC_GWAC_M2M	0
  49#define AT_XDMAC_GWAC_P2M	(AT_XDMAC_PW0(0xF) | AT_XDMAC_PW2(0xF))
  50
  51#define AT_XDMAC_GIE		0x0C	/* Global Interrupt Enable Register */
  52#define AT_XDMAC_GID		0x10	/* Global Interrupt Disable Register */
  53#define AT_XDMAC_GIM		0x14	/* Global Interrupt Mask Register */
  54#define AT_XDMAC_GIS		0x18	/* Global Interrupt Status Register */
  55#define AT_XDMAC_GE		0x1C	/* Global Channel Enable Register */
  56#define AT_XDMAC_GD		0x20	/* Global Channel Disable Register */
  57#define AT_XDMAC_GS		0x24	/* Global Channel Status Register */
  58#define AT_XDMAC_VERSION	0xFFC	/* XDMAC Version Register */
  59
  60/* Channel relative registers offsets */
  61#define AT_XDMAC_CIE		0x00	/* Channel Interrupt Enable Register */
  62#define		AT_XDMAC_CIE_BIE	BIT(0)	/* End of Block Interrupt Enable Bit */
  63#define		AT_XDMAC_CIE_LIE	BIT(1)	/* End of Linked List Interrupt Enable Bit */
  64#define		AT_XDMAC_CIE_DIE	BIT(2)	/* End of Disable Interrupt Enable Bit */
  65#define		AT_XDMAC_CIE_FIE	BIT(3)	/* End of Flush Interrupt Enable Bit */
  66#define		AT_XDMAC_CIE_RBEIE	BIT(4)	/* Read Bus Error Interrupt Enable Bit */
  67#define		AT_XDMAC_CIE_WBEIE	BIT(5)	/* Write Bus Error Interrupt Enable Bit */
  68#define		AT_XDMAC_CIE_ROIE	BIT(6)	/* Request Overflow Interrupt Enable Bit */
  69#define AT_XDMAC_CID		0x04	/* Channel Interrupt Disable Register */
  70#define		AT_XDMAC_CID_BID	BIT(0)	/* End of Block Interrupt Disable Bit */
  71#define		AT_XDMAC_CID_LID	BIT(1)	/* End of Linked List Interrupt Disable Bit */
  72#define		AT_XDMAC_CID_DID	BIT(2)	/* End of Disable Interrupt Disable Bit */
  73#define		AT_XDMAC_CID_FID	BIT(3)	/* End of Flush Interrupt Disable Bit */
  74#define		AT_XDMAC_CID_RBEID	BIT(4)	/* Read Bus Error Interrupt Disable Bit */
  75#define		AT_XDMAC_CID_WBEID	BIT(5)	/* Write Bus Error Interrupt Disable Bit */
  76#define		AT_XDMAC_CID_ROID	BIT(6)	/* Request Overflow Interrupt Disable Bit */
  77#define AT_XDMAC_CIM		0x08	/* Channel Interrupt Mask Register */
  78#define		AT_XDMAC_CIM_BIM	BIT(0)	/* End of Block Interrupt Mask Bit */
  79#define		AT_XDMAC_CIM_LIM	BIT(1)	/* End of Linked List Interrupt Mask Bit */
  80#define		AT_XDMAC_CIM_DIM	BIT(2)	/* End of Disable Interrupt Mask Bit */
  81#define		AT_XDMAC_CIM_FIM	BIT(3)	/* End of Flush Interrupt Mask Bit */
  82#define		AT_XDMAC_CIM_RBEIM	BIT(4)	/* Read Bus Error Interrupt Mask Bit */
  83#define		AT_XDMAC_CIM_WBEIM	BIT(5)	/* Write Bus Error Interrupt Mask Bit */
  84#define		AT_XDMAC_CIM_ROIM	BIT(6)	/* Request Overflow Interrupt Mask Bit */
  85#define AT_XDMAC_CIS		0x0C	/* Channel Interrupt Status Register */
  86#define		AT_XDMAC_CIS_BIS	BIT(0)	/* End of Block Interrupt Status Bit */
  87#define		AT_XDMAC_CIS_LIS	BIT(1)	/* End of Linked List Interrupt Status Bit */
  88#define		AT_XDMAC_CIS_DIS	BIT(2)	/* End of Disable Interrupt Status Bit */
  89#define		AT_XDMAC_CIS_FIS	BIT(3)	/* End of Flush Interrupt Status Bit */
  90#define		AT_XDMAC_CIS_RBEIS	BIT(4)	/* Read Bus Error Interrupt Status Bit */
  91#define		AT_XDMAC_CIS_WBEIS	BIT(5)	/* Write Bus Error Interrupt Status Bit */
  92#define		AT_XDMAC_CIS_ROIS	BIT(6)	/* Request Overflow Interrupt Status Bit */
  93#define AT_XDMAC_CSA		0x10	/* Channel Source Address Register */
  94#define AT_XDMAC_CDA		0x14	/* Channel Destination Address Register */
  95#define AT_XDMAC_CNDA		0x18	/* Channel Next Descriptor Address Register */
  96#define		AT_XDMAC_CNDA_NDAIF(i)	((i) & 0x1)			/* Channel x Next Descriptor Interface */
  97#define		AT_XDMAC_CNDA_NDA(i)	((i) & 0xfffffffc)		/* Channel x Next Descriptor Address */
  98#define AT_XDMAC_CNDC		0x1C	/* Channel Next Descriptor Control Register */
  99#define		AT_XDMAC_CNDC_NDE		(0x1 << 0)		/* Channel x Next Descriptor Enable */
 100#define		AT_XDMAC_CNDC_NDSUP		(0x1 << 1)		/* Channel x Next Descriptor Source Update */
 101#define		AT_XDMAC_CNDC_NDDUP		(0x1 << 2)		/* Channel x Next Descriptor Destination Update */
 
 102#define		AT_XDMAC_CNDC_NDVIEW_NDV0	(0x0 << 3)		/* Channel x Next Descriptor View 0 */
 103#define		AT_XDMAC_CNDC_NDVIEW_NDV1	(0x1 << 3)		/* Channel x Next Descriptor View 1 */
 104#define		AT_XDMAC_CNDC_NDVIEW_NDV2	(0x2 << 3)		/* Channel x Next Descriptor View 2 */
 105#define		AT_XDMAC_CNDC_NDVIEW_NDV3	(0x3 << 3)		/* Channel x Next Descriptor View 3 */
 106#define AT_XDMAC_CUBC		0x20	/* Channel Microblock Control Register */
 107#define AT_XDMAC_CBC		0x24	/* Channel Block Control Register */
 108#define AT_XDMAC_CC		0x28	/* Channel Configuration Register */
 109#define		AT_XDMAC_CC_TYPE	(0x1 << 0)	/* Channel Transfer Type */
 110#define			AT_XDMAC_CC_TYPE_MEM_TRAN	(0x0 << 0)	/* Memory to Memory Transfer */
 111#define			AT_XDMAC_CC_TYPE_PER_TRAN	(0x1 << 0)	/* Peripheral to Memory or Memory to Peripheral Transfer */
 112#define		AT_XDMAC_CC_MBSIZE_MASK	(0x3 << 1)
 113#define			AT_XDMAC_CC_MBSIZE_SINGLE	(0x0 << 1)
 114#define			AT_XDMAC_CC_MBSIZE_FOUR		(0x1 << 1)
 115#define			AT_XDMAC_CC_MBSIZE_EIGHT	(0x2 << 1)
 116#define			AT_XDMAC_CC_MBSIZE_SIXTEEN	(0x3 << 1)
 117#define		AT_XDMAC_CC_DSYNC	(0x1 << 4)	/* Channel Synchronization */
 118#define			AT_XDMAC_CC_DSYNC_PER2MEM	(0x0 << 4)
 119#define			AT_XDMAC_CC_DSYNC_MEM2PER	(0x1 << 4)
 120#define		AT_XDMAC_CC_PROT	(0x1 << 5)	/* Channel Protection */
 121#define			AT_XDMAC_CC_PROT_SEC		(0x0 << 5)
 122#define			AT_XDMAC_CC_PROT_UNSEC		(0x1 << 5)
 123#define		AT_XDMAC_CC_SWREQ	(0x1 << 6)	/* Channel Software Request Trigger */
 124#define			AT_XDMAC_CC_SWREQ_HWR_CONNECTED	(0x0 << 6)
 125#define			AT_XDMAC_CC_SWREQ_SWR_CONNECTED	(0x1 << 6)
 126#define		AT_XDMAC_CC_MEMSET	(0x1 << 7)	/* Channel Fill Block of memory */
 127#define			AT_XDMAC_CC_MEMSET_NORMAL_MODE	(0x0 << 7)
 128#define			AT_XDMAC_CC_MEMSET_HW_MODE	(0x1 << 7)
 129#define		AT_XDMAC_CC_CSIZE(i)	((0x7 & (i)) << 8)	/* Channel Chunk Size */
 130#define		AT_XDMAC_CC_DWIDTH_OFFSET	11
 131#define		AT_XDMAC_CC_DWIDTH_MASK	(0x3 << AT_XDMAC_CC_DWIDTH_OFFSET)
 132#define		AT_XDMAC_CC_DWIDTH(i)	((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET)	/* Channel Data Width */
 133#define			AT_XDMAC_CC_DWIDTH_BYTE		0x0
 134#define			AT_XDMAC_CC_DWIDTH_HALFWORD	0x1
 135#define			AT_XDMAC_CC_DWIDTH_WORD		0x2
 136#define			AT_XDMAC_CC_DWIDTH_DWORD	0x3
 137#define		AT_XDMAC_CC_SIF(i)	((0x1 & (i)) << 13)	/* Channel Source Interface Identifier */
 138#define		AT_XDMAC_CC_DIF(i)	((0x1 & (i)) << 14)	/* Channel Destination Interface Identifier */
 139#define		AT_XDMAC_CC_SAM_MASK	(0x3 << 16)	/* Channel Source Addressing Mode */
 140#define			AT_XDMAC_CC_SAM_FIXED_AM	(0x0 << 16)
 141#define			AT_XDMAC_CC_SAM_INCREMENTED_AM	(0x1 << 16)
 142#define			AT_XDMAC_CC_SAM_UBS_AM		(0x2 << 16)
 143#define			AT_XDMAC_CC_SAM_UBS_DS_AM	(0x3 << 16)
 144#define		AT_XDMAC_CC_DAM_MASK	(0x3 << 18)	/* Channel Source Addressing Mode */
 145#define			AT_XDMAC_CC_DAM_FIXED_AM	(0x0 << 18)
 146#define			AT_XDMAC_CC_DAM_INCREMENTED_AM	(0x1 << 18)
 147#define			AT_XDMAC_CC_DAM_UBS_AM		(0x2 << 18)
 148#define			AT_XDMAC_CC_DAM_UBS_DS_AM	(0x3 << 18)
 149#define		AT_XDMAC_CC_INITD	(0x1 << 21)	/* Channel Initialization Terminated (read only) */
 150#define			AT_XDMAC_CC_INITD_TERMINATED	(0x0 << 21)
 151#define			AT_XDMAC_CC_INITD_IN_PROGRESS	(0x1 << 21)
 152#define		AT_XDMAC_CC_RDIP	(0x1 << 22)	/* Read in Progress (read only) */
 153#define			AT_XDMAC_CC_RDIP_DONE		(0x0 << 22)
 154#define			AT_XDMAC_CC_RDIP_IN_PROGRESS	(0x1 << 22)
 155#define		AT_XDMAC_CC_WRIP	(0x1 << 23)	/* Write in Progress (read only) */
 156#define			AT_XDMAC_CC_WRIP_DONE		(0x0 << 23)
 157#define			AT_XDMAC_CC_WRIP_IN_PROGRESS	(0x1 << 23)
 158#define		AT_XDMAC_CC_PERID(i)	(0x7f & (i) << 24)	/* Channel Peripheral Identifier */
 159#define AT_XDMAC_CDS_MSP	0x2C	/* Channel Data Stride Memory Set Pattern */
 160#define AT_XDMAC_CSUS		0x30	/* Channel Source Microblock Stride */
 161#define AT_XDMAC_CDUS		0x34	/* Channel Destination Microblock Stride */
 162
 163/* Microblock control members */
 164#define AT_XDMAC_MBR_UBC_UBLEN_MAX	0xFFFFFFUL	/* Maximum Microblock Length */
 165#define AT_XDMAC_MBR_UBC_NDE		(0x1 << 24)	/* Next Descriptor Enable */
 166#define AT_XDMAC_MBR_UBC_NSEN		(0x1 << 25)	/* Next Descriptor Source Update */
 167#define AT_XDMAC_MBR_UBC_NDEN		(0x1 << 26)	/* Next Descriptor Destination Update */
 168#define AT_XDMAC_MBR_UBC_NDV0		(0x0 << 27)	/* Next Descriptor View 0 */
 169#define AT_XDMAC_MBR_UBC_NDV1		(0x1 << 27)	/* Next Descriptor View 1 */
 170#define AT_XDMAC_MBR_UBC_NDV2		(0x2 << 27)	/* Next Descriptor View 2 */
 171#define AT_XDMAC_MBR_UBC_NDV3		(0x3 << 27)	/* Next Descriptor View 3 */
 172
 173#define AT_XDMAC_MAX_CHAN	0x20
 174#define AT_XDMAC_MAX_CSIZE	16	/* 16 data */
 175#define AT_XDMAC_MAX_DWIDTH	8	/* 64 bits */
 176#define AT_XDMAC_RESIDUE_MAX_RETRIES	5
 177
 178#define AT_XDMAC_DMA_BUSWIDTHS\
 179	(BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
 180	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\
 181	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\
 182	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\
 183	BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
 184
 185enum atc_status {
 186	AT_XDMAC_CHAN_IS_CYCLIC = 0,
 187	AT_XDMAC_CHAN_IS_PAUSED,
 
 188};
 189
 190struct at_xdmac_layout {
 191	/* Global Channel Read Suspend Register */
 192	u8				grs;
 193	/* Global Write Suspend Register */
 194	u8				gws;
 195	/* Global Channel Read Write Suspend Register */
 196	u8				grws;
 197	/* Global Channel Read Write Resume Register */
 198	u8				grwr;
 199	/* Global Channel Software Request Register */
 200	u8				gswr;
 201	/* Global channel Software Request Status Register */
 202	u8				gsws;
 203	/* Global Channel Software Flush Request Register */
 204	u8				gswf;
 205	/* Channel reg base */
 206	u8				chan_cc_reg_base;
 207	/* Source/Destination Interface must be specified or not */
 208	bool				sdif;
 209	/* AXI queue priority configuration supported */
 210	bool				axi_config;
 211};
 212
 213/* ----- Channels ----- */
 214struct at_xdmac_chan {
 215	struct dma_chan			chan;
 216	void __iomem			*ch_regs;
 217	u32				mask;		/* Channel Mask */
 218	u32				cfg;		/* Channel Configuration Register */
 219	u8				perid;		/* Peripheral ID */
 220	u8				perif;		/* Peripheral Interface */
 221	u8				memif;		/* Memory Interface */
 222	u32				save_cc;
 223	u32				save_cim;
 224	u32				save_cnda;
 225	u32				save_cndc;
 226	u32				irq_status;
 227	unsigned long			status;
 228	struct tasklet_struct		tasklet;
 229	struct dma_slave_config		sconfig;
 230
 231	spinlock_t			lock;
 232
 233	struct list_head		xfers_list;
 234	struct list_head		free_descs_list;
 235};
 236
 237
 238/* ----- Controller ----- */
 239struct at_xdmac {
 240	struct dma_device	dma;
 241	void __iomem		*regs;
 
 242	int			irq;
 243	struct clk		*clk;
 244	u32			save_gim;
 
 245	struct dma_pool		*at_xdmac_desc_pool;
 246	const struct at_xdmac_layout	*layout;
 247	struct at_xdmac_chan	chan[];
 248};
 249
 250
 251/* ----- Descriptors ----- */
 252
 253/* Linked List Descriptor */
 254struct at_xdmac_lld {
 255	dma_addr_t	mbr_nda;	/* Next Descriptor Member */
 256	u32		mbr_ubc;	/* Microblock Control Member */
 257	dma_addr_t	mbr_sa;		/* Source Address Member */
 258	dma_addr_t	mbr_da;		/* Destination Address Member */
 259	u32		mbr_cfg;	/* Configuration Register */
 260	u32		mbr_bc;		/* Block Control Register */
 261	u32		mbr_ds;		/* Data Stride Register */
 262	u32		mbr_sus;	/* Source Microblock Stride Register */
 263	u32		mbr_dus;	/* Destination Microblock Stride Register */
 264};
 265
 266/* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */
 267struct at_xdmac_desc {
 268	struct at_xdmac_lld		lld;
 269	enum dma_transfer_direction	direction;
 270	struct dma_async_tx_descriptor	tx_dma_desc;
 271	struct list_head		desc_node;
 272	/* Following members are only used by the first descriptor */
 273	bool				active_xfer;
 274	unsigned int			xfer_size;
 275	struct list_head		descs_list;
 276	struct list_head		xfer_node;
 277} __aligned(sizeof(u64));
 278
 279static const struct at_xdmac_layout at_xdmac_sama5d4_layout = {
 280	.grs = 0x28,
 281	.gws = 0x2C,
 282	.grws = 0x30,
 283	.grwr = 0x34,
 284	.gswr = 0x38,
 285	.gsws = 0x3C,
 286	.gswf = 0x40,
 287	.chan_cc_reg_base = 0x50,
 288	.sdif = true,
 289	.axi_config = false,
 290};
 291
 292static const struct at_xdmac_layout at_xdmac_sama7g5_layout = {
 293	.grs = 0x30,
 294	.gws = 0x38,
 295	.grws = 0x40,
 296	.grwr = 0x44,
 297	.gswr = 0x48,
 298	.gsws = 0x4C,
 299	.gswf = 0x50,
 300	.chan_cc_reg_base = 0x60,
 301	.sdif = false,
 302	.axi_config = true,
 303};
 304
 305static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb)
 306{
 307	return atxdmac->regs + (atxdmac->layout->chan_cc_reg_base + chan_nb * 0x40);
 308}
 309
 310#define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg))
 311#define at_xdmac_write(atxdmac, reg, value) \
 312	writel_relaxed((value), (atxdmac)->regs + (reg))
 313
 314#define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg))
 315#define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg))
 316
 317static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan)
 318{
 319	return container_of(dchan, struct at_xdmac_chan, chan);
 320}
 321
 322static struct device *chan2dev(struct dma_chan *chan)
 323{
 324	return &chan->dev->device;
 325}
 326
 327static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev)
 328{
 329	return container_of(ddev, struct at_xdmac, dma);
 330}
 331
 332static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd)
 333{
 334	return container_of(txd, struct at_xdmac_desc, tx_dma_desc);
 335}
 336
 337static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan)
 338{
 339	return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
 340}
 341
 342static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan)
 343{
 344	return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
 345}
 346
 
 
 
 
 
 347static inline bool at_xdmac_chan_is_peripheral_xfer(u32 cfg)
 348{
 349	return cfg & AT_XDMAC_CC_TYPE_PER_TRAN;
 350}
 351
 352static inline u8 at_xdmac_get_dwidth(u32 cfg)
 353{
 354	return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
 355};
 356
 357static unsigned int init_nr_desc_per_channel = 64;
 358module_param(init_nr_desc_per_channel, uint, 0644);
 359MODULE_PARM_DESC(init_nr_desc_per_channel,
 360		 "initial descriptors per channel (default: 64)");
 361
 362
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 363static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan)
 364{
 365	return at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask;
 
 
 
 
 
 
 
 
 
 
 
 
 366}
 367
 368static void at_xdmac_off(struct at_xdmac *atxdmac)
 369{
 
 
 
 
 
 
 
 
 370	at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L);
 371
 372	/* Wait that all chans are disabled. */
 373	while (at_xdmac_read(atxdmac, AT_XDMAC_GS))
 374		cpu_relax();
 375
 376	at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L);
 
 
 
 
 
 
 
 
 
 
 
 
 377}
 378
 379/* Call with lock hold. */
 380static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
 381				struct at_xdmac_desc *first)
 382{
 383	struct at_xdmac	*atxdmac = to_at_xdmac(atchan->chan.device);
 384	u32		reg;
 
 
 
 
 
 385
 386	dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
 387
 388	if (at_xdmac_chan_is_enabled(atchan))
 389		return;
 390
 391	/* Set transfer as active to not try to start it again. */
 392	first->active_xfer = true;
 393
 394	/* Tell xdmac where to get the first descriptor. */
 395	reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys);
 396	if (atxdmac->layout->sdif)
 397		reg |= AT_XDMAC_CNDA_NDAIF(atchan->memif);
 398
 399	at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
 400
 401	/*
 402	 * When doing non cyclic transfer we need to use the next
 403	 * descriptor view 2 since some fields of the configuration register
 404	 * depend on transfer size and src/dest addresses.
 405	 */
 406	if (at_xdmac_chan_is_cyclic(atchan))
 407		reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
 408	else if (first->lld.mbr_ubc & AT_XDMAC_MBR_UBC_NDV3)
 
 409		reg = AT_XDMAC_CNDC_NDVIEW_NDV3;
 410	else
 411		reg = AT_XDMAC_CNDC_NDVIEW_NDV2;
 412	/*
 413	 * Even if the register will be updated from the configuration in the
 414	 * descriptor when using view 2 or higher, the PROT bit won't be set
 415	 * properly. This bit can be modified only by using the channel
 416	 * configuration register.
 417	 */
 418	at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
 419
 420	reg |= AT_XDMAC_CNDC_NDDUP
 421	       | AT_XDMAC_CNDC_NDSUP
 422	       | AT_XDMAC_CNDC_NDE;
 423	at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg);
 424
 425	dev_vdbg(chan2dev(&atchan->chan),
 426		 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
 427		 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
 428		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
 429		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
 430		 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
 431		 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
 432		 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 433
 434	at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
 435	reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE;
 436	/*
 437	 * Request Overflow Error is only for peripheral synchronized transfers
 438	 */
 439	if (at_xdmac_chan_is_peripheral_xfer(first->lld.mbr_cfg))
 440		reg |= AT_XDMAC_CIE_ROIE;
 441
 442	/*
 443	 * There is no end of list when doing cyclic dma, we need to get
 444	 * an interrupt after each periods.
 445	 */
 446	if (at_xdmac_chan_is_cyclic(atchan))
 447		at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
 448				    reg | AT_XDMAC_CIE_BIE);
 449	else
 450		at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
 451				    reg | AT_XDMAC_CIE_LIE);
 452	at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask);
 453	dev_vdbg(chan2dev(&atchan->chan),
 454		 "%s: enable channel (0x%08x)\n", __func__, atchan->mask);
 455	wmb();
 456	at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
 457
 458	dev_vdbg(chan2dev(&atchan->chan),
 459		 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
 460		 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
 461		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
 462		 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
 463		 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
 464		 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
 465		 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 466
 467}
 468
 469static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx)
 470{
 471	struct at_xdmac_desc	*desc = txd_to_at_desc(tx);
 472	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(tx->chan);
 473	dma_cookie_t		cookie;
 474	unsigned long		irqflags;
 475
 476	spin_lock_irqsave(&atchan->lock, irqflags);
 477	cookie = dma_cookie_assign(tx);
 478
 
 
 
 479	dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n",
 480		 __func__, atchan, desc);
 481	list_add_tail(&desc->xfer_node, &atchan->xfers_list);
 482	if (list_is_singular(&atchan->xfers_list))
 483		at_xdmac_start_xfer(atchan, desc);
 484
 485	spin_unlock_irqrestore(&atchan->lock, irqflags);
 486	return cookie;
 487}
 488
 489static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan,
 490						 gfp_t gfp_flags)
 491{
 492	struct at_xdmac_desc	*desc;
 493	struct at_xdmac		*atxdmac = to_at_xdmac(chan->device);
 494	dma_addr_t		phys;
 495
 496	desc = dma_pool_zalloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys);
 497	if (desc) {
 498		INIT_LIST_HEAD(&desc->descs_list);
 499		dma_async_tx_descriptor_init(&desc->tx_dma_desc, chan);
 500		desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit;
 501		desc->tx_dma_desc.phys = phys;
 502	}
 503
 504	return desc;
 505}
 506
 507static void at_xdmac_init_used_desc(struct at_xdmac_desc *desc)
 508{
 509	memset(&desc->lld, 0, sizeof(desc->lld));
 510	INIT_LIST_HEAD(&desc->descs_list);
 511	desc->direction = DMA_TRANS_NONE;
 512	desc->xfer_size = 0;
 513	desc->active_xfer = false;
 514}
 515
 516/* Call must be protected by lock. */
 517static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan)
 518{
 519	struct at_xdmac_desc *desc;
 520
 521	if (list_empty(&atchan->free_descs_list)) {
 522		desc = at_xdmac_alloc_desc(&atchan->chan, GFP_NOWAIT);
 523	} else {
 524		desc = list_first_entry(&atchan->free_descs_list,
 525					struct at_xdmac_desc, desc_node);
 526		list_del(&desc->desc_node);
 527		at_xdmac_init_used_desc(desc);
 528	}
 529
 530	return desc;
 531}
 532
 533static void at_xdmac_queue_desc(struct dma_chan *chan,
 534				struct at_xdmac_desc *prev,
 535				struct at_xdmac_desc *desc)
 536{
 537	if (!prev || !desc)
 538		return;
 539
 540	prev->lld.mbr_nda = desc->tx_dma_desc.phys;
 541	prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE;
 542
 543	dev_dbg(chan2dev(chan),	"%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
 544		__func__, prev, &prev->lld.mbr_nda);
 545}
 546
 547static inline void at_xdmac_increment_block_count(struct dma_chan *chan,
 548						  struct at_xdmac_desc *desc)
 549{
 550	if (!desc)
 551		return;
 552
 553	desc->lld.mbr_bc++;
 554
 555	dev_dbg(chan2dev(chan),
 556		"%s: incrementing the block count of the desc 0x%p\n",
 557		__func__, desc);
 558}
 559
 560static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
 561				       struct of_dma *of_dma)
 562{
 563	struct at_xdmac		*atxdmac = of_dma->of_dma_data;
 564	struct at_xdmac_chan	*atchan;
 565	struct dma_chan		*chan;
 566	struct device		*dev = atxdmac->dma.dev;
 567
 568	if (dma_spec->args_count != 1) {
 569		dev_err(dev, "dma phandler args: bad number of args\n");
 570		return NULL;
 571	}
 572
 573	chan = dma_get_any_slave_channel(&atxdmac->dma);
 574	if (!chan) {
 575		dev_err(dev, "can't get a dma channel\n");
 576		return NULL;
 577	}
 578
 579	atchan = to_at_xdmac_chan(chan);
 580	atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]);
 581	atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]);
 582	atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]);
 583	dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n",
 584		 atchan->memif, atchan->perif, atchan->perid);
 585
 586	return chan;
 587}
 588
 589static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
 590				      enum dma_transfer_direction direction)
 591{
 592	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 593	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
 594	int			csize, dwidth;
 595
 596	if (direction == DMA_DEV_TO_MEM) {
 597		atchan->cfg =
 598			AT91_XDMAC_DT_PERID(atchan->perid)
 599			| AT_XDMAC_CC_DAM_INCREMENTED_AM
 600			| AT_XDMAC_CC_SAM_FIXED_AM
 601			| AT_XDMAC_CC_SWREQ_HWR_CONNECTED
 602			| AT_XDMAC_CC_DSYNC_PER2MEM
 603			| AT_XDMAC_CC_MBSIZE_SIXTEEN
 604			| AT_XDMAC_CC_TYPE_PER_TRAN;
 605		if (atxdmac->layout->sdif)
 606			atchan->cfg |= AT_XDMAC_CC_DIF(atchan->memif) |
 607				       AT_XDMAC_CC_SIF(atchan->perif);
 608
 609		csize = ffs(atchan->sconfig.src_maxburst) - 1;
 610		if (csize < 0) {
 611			dev_err(chan2dev(chan), "invalid src maxburst value\n");
 612			return -EINVAL;
 613		}
 614		atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
 615		dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
 616		if (dwidth < 0) {
 617			dev_err(chan2dev(chan), "invalid src addr width value\n");
 618			return -EINVAL;
 619		}
 620		atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
 621	} else if (direction == DMA_MEM_TO_DEV) {
 622		atchan->cfg =
 623			AT91_XDMAC_DT_PERID(atchan->perid)
 624			| AT_XDMAC_CC_DAM_FIXED_AM
 625			| AT_XDMAC_CC_SAM_INCREMENTED_AM
 626			| AT_XDMAC_CC_SWREQ_HWR_CONNECTED
 627			| AT_XDMAC_CC_DSYNC_MEM2PER
 628			| AT_XDMAC_CC_MBSIZE_SIXTEEN
 629			| AT_XDMAC_CC_TYPE_PER_TRAN;
 630		if (atxdmac->layout->sdif)
 631			atchan->cfg |= AT_XDMAC_CC_DIF(atchan->perif) |
 632				       AT_XDMAC_CC_SIF(atchan->memif);
 633
 634		csize = ffs(atchan->sconfig.dst_maxburst) - 1;
 635		if (csize < 0) {
 636			dev_err(chan2dev(chan), "invalid src maxburst value\n");
 637			return -EINVAL;
 638		}
 639		atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
 640		dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
 641		if (dwidth < 0) {
 642			dev_err(chan2dev(chan), "invalid dst addr width value\n");
 643			return -EINVAL;
 644		}
 645		atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
 646	}
 647
 648	dev_dbg(chan2dev(chan),	"%s: cfg=0x%08x\n", __func__, atchan->cfg);
 649
 650	return 0;
 651}
 652
 653/*
 654 * Only check that maxburst and addr width values are supported by the
 655 * the controller but not that the configuration is good to perform the
 656 * transfer since we don't know the direction at this stage.
 657 */
 658static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
 659{
 660	if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
 661	    || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
 662		return -EINVAL;
 663
 664	if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
 665	    || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
 666		return -EINVAL;
 667
 668	return 0;
 669}
 670
 671static int at_xdmac_set_slave_config(struct dma_chan *chan,
 672				      struct dma_slave_config *sconfig)
 673{
 674	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 675
 676	if (at_xdmac_check_slave_config(sconfig)) {
 677		dev_err(chan2dev(chan), "invalid slave configuration\n");
 678		return -EINVAL;
 679	}
 680
 681	memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
 682
 683	return 0;
 684}
 685
 686static struct dma_async_tx_descriptor *
 687at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 688		       unsigned int sg_len, enum dma_transfer_direction direction,
 689		       unsigned long flags, void *context)
 690{
 691	struct at_xdmac_chan		*atchan = to_at_xdmac_chan(chan);
 692	struct at_xdmac_desc		*first = NULL, *prev = NULL;
 693	struct scatterlist		*sg;
 694	int				i;
 695	unsigned int			xfer_size = 0;
 696	unsigned long			irqflags;
 697	struct dma_async_tx_descriptor	*ret = NULL;
 698
 699	if (!sgl)
 700		return NULL;
 701
 702	if (!is_slave_direction(direction)) {
 703		dev_err(chan2dev(chan), "invalid DMA direction\n");
 704		return NULL;
 705	}
 706
 707	dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n",
 708		 __func__, sg_len,
 709		 direction == DMA_MEM_TO_DEV ? "to device" : "from device",
 710		 flags);
 711
 712	/* Protect dma_sconfig field that can be modified by set_slave_conf. */
 713	spin_lock_irqsave(&atchan->lock, irqflags);
 714
 715	if (at_xdmac_compute_chan_conf(chan, direction))
 716		goto spin_unlock;
 717
 718	/* Prepare descriptors. */
 719	for_each_sg(sgl, sg, sg_len, i) {
 720		struct at_xdmac_desc	*desc = NULL;
 721		u32			len, mem, dwidth, fixed_dwidth;
 722
 723		len = sg_dma_len(sg);
 724		mem = sg_dma_address(sg);
 725		if (unlikely(!len)) {
 726			dev_err(chan2dev(chan), "sg data length is zero\n");
 727			goto spin_unlock;
 728		}
 729		dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n",
 730			 __func__, i, len, mem);
 731
 732		desc = at_xdmac_get_desc(atchan);
 733		if (!desc) {
 734			dev_err(chan2dev(chan), "can't get descriptor\n");
 735			if (first)
 736				list_splice_init(&first->descs_list, &atchan->free_descs_list);
 
 737			goto spin_unlock;
 738		}
 739
 740		/* Linked list descriptor setup. */
 741		if (direction == DMA_DEV_TO_MEM) {
 742			desc->lld.mbr_sa = atchan->sconfig.src_addr;
 743			desc->lld.mbr_da = mem;
 744		} else {
 745			desc->lld.mbr_sa = mem;
 746			desc->lld.mbr_da = atchan->sconfig.dst_addr;
 747		}
 748		dwidth = at_xdmac_get_dwidth(atchan->cfg);
 749		fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
 750			       ? dwidth
 751			       : AT_XDMAC_CC_DWIDTH_BYTE;
 752		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2			/* next descriptor view */
 753			| AT_XDMAC_MBR_UBC_NDEN					/* next descriptor dst parameter update */
 754			| AT_XDMAC_MBR_UBC_NSEN					/* next descriptor src parameter update */
 755			| (len >> fixed_dwidth);				/* microblock length */
 756		desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) |
 757				    AT_XDMAC_CC_DWIDTH(fixed_dwidth);
 758		dev_dbg(chan2dev(chan),
 759			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
 760			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
 761
 762		/* Chain lld. */
 763		if (prev)
 764			at_xdmac_queue_desc(chan, prev, desc);
 765
 766		prev = desc;
 767		if (!first)
 768			first = desc;
 769
 770		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
 771			 __func__, desc, first);
 772		list_add_tail(&desc->desc_node, &first->descs_list);
 773		xfer_size += len;
 774	}
 775
 776
 777	first->tx_dma_desc.flags = flags;
 778	first->xfer_size = xfer_size;
 779	first->direction = direction;
 780	ret = &first->tx_dma_desc;
 781
 782spin_unlock:
 783	spin_unlock_irqrestore(&atchan->lock, irqflags);
 784	return ret;
 785}
 786
 787static struct dma_async_tx_descriptor *
 788at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
 789			 size_t buf_len, size_t period_len,
 790			 enum dma_transfer_direction direction,
 791			 unsigned long flags)
 792{
 793	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
 794	struct at_xdmac_desc	*first = NULL, *prev = NULL;
 795	unsigned int		periods = buf_len / period_len;
 796	int			i;
 797	unsigned long		irqflags;
 798
 799	dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n",
 800		__func__, &buf_addr, buf_len, period_len,
 801		direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags);
 802
 803	if (!is_slave_direction(direction)) {
 804		dev_err(chan2dev(chan), "invalid DMA direction\n");
 805		return NULL;
 806	}
 807
 808	if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
 809		dev_err(chan2dev(chan), "channel currently used\n");
 810		return NULL;
 811	}
 812
 813	if (at_xdmac_compute_chan_conf(chan, direction))
 814		return NULL;
 815
 816	for (i = 0; i < periods; i++) {
 817		struct at_xdmac_desc	*desc = NULL;
 818
 819		spin_lock_irqsave(&atchan->lock, irqflags);
 820		desc = at_xdmac_get_desc(atchan);
 821		if (!desc) {
 822			dev_err(chan2dev(chan), "can't get descriptor\n");
 823			if (first)
 824				list_splice_init(&first->descs_list, &atchan->free_descs_list);
 
 825			spin_unlock_irqrestore(&atchan->lock, irqflags);
 826			return NULL;
 827		}
 828		spin_unlock_irqrestore(&atchan->lock, irqflags);
 829		dev_dbg(chan2dev(chan),
 830			"%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
 831			__func__, desc, &desc->tx_dma_desc.phys);
 832
 833		if (direction == DMA_DEV_TO_MEM) {
 834			desc->lld.mbr_sa = atchan->sconfig.src_addr;
 835			desc->lld.mbr_da = buf_addr + i * period_len;
 836		} else {
 837			desc->lld.mbr_sa = buf_addr + i * period_len;
 838			desc->lld.mbr_da = atchan->sconfig.dst_addr;
 839		}
 840		desc->lld.mbr_cfg = atchan->cfg;
 841		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
 842			| AT_XDMAC_MBR_UBC_NDEN
 843			| AT_XDMAC_MBR_UBC_NSEN
 844			| period_len >> at_xdmac_get_dwidth(desc->lld.mbr_cfg);
 845
 846		dev_dbg(chan2dev(chan),
 847			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
 848			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
 849
 850		/* Chain lld. */
 851		if (prev)
 852			at_xdmac_queue_desc(chan, prev, desc);
 853
 854		prev = desc;
 855		if (!first)
 856			first = desc;
 857
 858		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
 859			 __func__, desc, first);
 860		list_add_tail(&desc->desc_node, &first->descs_list);
 861	}
 862
 863	at_xdmac_queue_desc(chan, prev, first);
 864	first->tx_dma_desc.flags = flags;
 865	first->xfer_size = buf_len;
 866	first->direction = direction;
 867
 868	return &first->tx_dma_desc;
 869}
 870
 871static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr)
 872{
 873	u32 width;
 874
 875	/*
 876	 * Check address alignment to select the greater data width we
 877	 * can use.
 878	 *
 879	 * Some XDMAC implementations don't provide dword transfer, in
 880	 * this case selecting dword has the same behavior as
 881	 * selecting word transfers.
 882	 */
 883	if (!(addr & 7)) {
 884		width = AT_XDMAC_CC_DWIDTH_DWORD;
 885		dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__);
 886	} else if (!(addr & 3)) {
 887		width = AT_XDMAC_CC_DWIDTH_WORD;
 888		dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__);
 889	} else if (!(addr & 1)) {
 890		width = AT_XDMAC_CC_DWIDTH_HALFWORD;
 891		dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__);
 892	} else {
 893		width = AT_XDMAC_CC_DWIDTH_BYTE;
 894		dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__);
 895	}
 896
 897	return width;
 898}
 899
 900static struct at_xdmac_desc *
 901at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
 902				struct at_xdmac_chan *atchan,
 903				struct at_xdmac_desc *prev,
 904				dma_addr_t src, dma_addr_t dst,
 905				struct dma_interleaved_template *xt,
 906				struct data_chunk *chunk)
 907{
 908	struct at_xdmac_desc	*desc;
 909	u32			dwidth;
 910	unsigned long		flags;
 911	size_t			ublen;
 912	/*
 913	 * WARNING: The channel configuration is set here since there is no
 914	 * dmaengine_slave_config call in this case. Moreover we don't know the
 915	 * direction, it involves we can't dynamically set the source and dest
 916	 * interface so we have to use the same one. Only interface 0 allows EBI
 917	 * access. Hopefully we can access DDR through both ports (at least on
 918	 * SAMA5D4x), so we can use the same interface for source and dest,
 919	 * that solves the fact we don't know the direction.
 920	 * ERRATA: Even if useless for memory transfers, the PERID has to not
 921	 * match the one of another channel. If not, it could lead to spurious
 922	 * flag status.
 923	 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
 924	 * Thus, no need to have the SIF/DIF interfaces here.
 925	 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
 926	 * zero.
 927	 */
 928	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
 929					| AT_XDMAC_CC_MBSIZE_SIXTEEN
 930					| AT_XDMAC_CC_TYPE_MEM_TRAN;
 931
 932	dwidth = at_xdmac_align_width(chan, src | dst | chunk->size);
 933	if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
 934		dev_dbg(chan2dev(chan),
 935			"%s: chunk too big (%zu, max size %lu)...\n",
 936			__func__, chunk->size,
 937			AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth);
 938		return NULL;
 939	}
 940
 941	if (prev)
 942		dev_dbg(chan2dev(chan),
 943			"Adding items at the end of desc 0x%p\n", prev);
 944
 945	if (xt->src_inc) {
 946		if (xt->src_sgl)
 947			chan_cc |=  AT_XDMAC_CC_SAM_UBS_AM;
 948		else
 949			chan_cc |=  AT_XDMAC_CC_SAM_INCREMENTED_AM;
 950	}
 951
 952	if (xt->dst_inc) {
 953		if (xt->dst_sgl)
 954			chan_cc |=  AT_XDMAC_CC_DAM_UBS_AM;
 955		else
 956			chan_cc |=  AT_XDMAC_CC_DAM_INCREMENTED_AM;
 957	}
 958
 959	spin_lock_irqsave(&atchan->lock, flags);
 960	desc = at_xdmac_get_desc(atchan);
 961	spin_unlock_irqrestore(&atchan->lock, flags);
 962	if (!desc) {
 963		dev_err(chan2dev(chan), "can't get descriptor\n");
 964		return NULL;
 965	}
 966
 967	chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
 968
 969	ublen = chunk->size >> dwidth;
 970
 971	desc->lld.mbr_sa = src;
 972	desc->lld.mbr_da = dst;
 973	desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
 974	desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
 975
 976	desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
 977		| AT_XDMAC_MBR_UBC_NDEN
 978		| AT_XDMAC_MBR_UBC_NSEN
 979		| ublen;
 980	desc->lld.mbr_cfg = chan_cc;
 981
 982	dev_dbg(chan2dev(chan),
 983		"%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
 984		__func__, &desc->lld.mbr_sa, &desc->lld.mbr_da,
 985		desc->lld.mbr_ubc, desc->lld.mbr_cfg);
 986
 987	/* Chain lld. */
 988	if (prev)
 989		at_xdmac_queue_desc(chan, prev, desc);
 990
 991	return desc;
 992}
 993
 994static struct dma_async_tx_descriptor *
 995at_xdmac_prep_interleaved(struct dma_chan *chan,
 996			  struct dma_interleaved_template *xt,
 997			  unsigned long flags)
 998{
 999	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1000	struct at_xdmac_desc	*prev = NULL, *first = NULL;
1001	dma_addr_t		dst_addr, src_addr;
1002	size_t			src_skip = 0, dst_skip = 0, len = 0;
1003	struct data_chunk	*chunk;
1004	int			i;
1005
1006	if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
1007		return NULL;
1008
1009	/*
1010	 * TODO: Handle the case where we have to repeat a chain of
1011	 * descriptors...
1012	 */
1013	if ((xt->numf > 1) && (xt->frame_size > 1))
1014		return NULL;
1015
1016	dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%zu, frame_size=%zu, flags=0x%lx\n",
1017		__func__, &xt->src_start, &xt->dst_start,	xt->numf,
1018		xt->frame_size, flags);
1019
1020	src_addr = xt->src_start;
1021	dst_addr = xt->dst_start;
1022
1023	if (xt->numf > 1) {
1024		first = at_xdmac_interleaved_queue_desc(chan, atchan,
1025							NULL,
1026							src_addr, dst_addr,
1027							xt, xt->sgl);
 
 
1028
1029		/* Length of the block is (BLEN+1) microblocks. */
1030		for (i = 0; i < xt->numf - 1; i++)
1031			at_xdmac_increment_block_count(chan, first);
1032
1033		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1034			__func__, first, first);
1035		list_add_tail(&first->desc_node, &first->descs_list);
1036	} else {
1037		for (i = 0; i < xt->frame_size; i++) {
1038			size_t src_icg = 0, dst_icg = 0;
1039			struct at_xdmac_desc *desc;
1040
1041			chunk = xt->sgl + i;
1042
1043			dst_icg = dmaengine_get_dst_icg(xt, chunk);
1044			src_icg = dmaengine_get_src_icg(xt, chunk);
1045
1046			src_skip = chunk->size + src_icg;
1047			dst_skip = chunk->size + dst_icg;
1048
1049			dev_dbg(chan2dev(chan),
1050				"%s: chunk size=%zu, src icg=%zu, dst icg=%zu\n",
1051				__func__, chunk->size, src_icg, dst_icg);
1052
1053			desc = at_xdmac_interleaved_queue_desc(chan, atchan,
1054							       prev,
1055							       src_addr, dst_addr,
1056							       xt, chunk);
1057			if (!desc) {
1058				list_splice_init(&first->descs_list,
1059						 &atchan->free_descs_list);
 
1060				return NULL;
1061			}
1062
1063			if (!first)
1064				first = desc;
1065
1066			dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1067				__func__, desc, first);
1068			list_add_tail(&desc->desc_node, &first->descs_list);
1069
1070			if (xt->src_sgl)
1071				src_addr += src_skip;
1072
1073			if (xt->dst_sgl)
1074				dst_addr += dst_skip;
1075
1076			len += chunk->size;
1077			prev = desc;
1078		}
1079	}
1080
1081	first->tx_dma_desc.cookie = -EBUSY;
1082	first->tx_dma_desc.flags = flags;
1083	first->xfer_size = len;
1084
1085	return &first->tx_dma_desc;
1086}
1087
1088static struct dma_async_tx_descriptor *
1089at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1090			 size_t len, unsigned long flags)
1091{
1092	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1093	struct at_xdmac_desc	*first = NULL, *prev = NULL;
1094	size_t			remaining_size = len, xfer_size = 0, ublen;
1095	dma_addr_t		src_addr = src, dst_addr = dest;
1096	u32			dwidth;
1097	/*
1098	 * WARNING: We don't know the direction, it involves we can't
1099	 * dynamically set the source and dest interface so we have to use the
1100	 * same one. Only interface 0 allows EBI access. Hopefully we can
1101	 * access DDR through both ports (at least on SAMA5D4x), so we can use
1102	 * the same interface for source and dest, that solves the fact we
1103	 * don't know the direction.
1104	 * ERRATA: Even if useless for memory transfers, the PERID has to not
1105	 * match the one of another channel. If not, it could lead to spurious
1106	 * flag status.
1107	 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1108	 * Thus, no need to have the SIF/DIF interfaces here.
1109	 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1110	 * zero.
1111	 */
1112	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
1113					| AT_XDMAC_CC_DAM_INCREMENTED_AM
1114					| AT_XDMAC_CC_SAM_INCREMENTED_AM
1115					| AT_XDMAC_CC_MBSIZE_SIXTEEN
1116					| AT_XDMAC_CC_TYPE_MEM_TRAN;
1117	unsigned long		irqflags;
1118
1119	dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n",
1120		__func__, &src, &dest, len, flags);
1121
1122	if (unlikely(!len))
1123		return NULL;
1124
1125	dwidth = at_xdmac_align_width(chan, src_addr | dst_addr);
1126
1127	/* Prepare descriptors. */
1128	while (remaining_size) {
1129		struct at_xdmac_desc	*desc = NULL;
1130
1131		dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size);
1132
1133		spin_lock_irqsave(&atchan->lock, irqflags);
1134		desc = at_xdmac_get_desc(atchan);
1135		spin_unlock_irqrestore(&atchan->lock, irqflags);
1136		if (!desc) {
1137			dev_err(chan2dev(chan), "can't get descriptor\n");
1138			if (first)
1139				list_splice_init(&first->descs_list, &atchan->free_descs_list);
 
1140			return NULL;
1141		}
1142
1143		/* Update src and dest addresses. */
1144		src_addr += xfer_size;
1145		dst_addr += xfer_size;
1146
1147		if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)
1148			xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth;
1149		else
1150			xfer_size = remaining_size;
1151
1152		dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size);
1153
1154		/* Check remaining length and change data width if needed. */
1155		dwidth = at_xdmac_align_width(chan,
1156					      src_addr | dst_addr | xfer_size);
1157		chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK;
1158		chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1159
1160		ublen = xfer_size >> dwidth;
1161		remaining_size -= xfer_size;
1162
1163		desc->lld.mbr_sa = src_addr;
1164		desc->lld.mbr_da = dst_addr;
1165		desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2
1166			| AT_XDMAC_MBR_UBC_NDEN
1167			| AT_XDMAC_MBR_UBC_NSEN
1168			| ublen;
1169		desc->lld.mbr_cfg = chan_cc;
1170
1171		dev_dbg(chan2dev(chan),
1172			 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1173			 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1174
1175		/* Chain lld. */
1176		if (prev)
1177			at_xdmac_queue_desc(chan, prev, desc);
1178
1179		prev = desc;
1180		if (!first)
1181			first = desc;
1182
1183		dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1184			 __func__, desc, first);
1185		list_add_tail(&desc->desc_node, &first->descs_list);
1186	}
1187
1188	first->tx_dma_desc.flags = flags;
1189	first->xfer_size = len;
1190
1191	return &first->tx_dma_desc;
1192}
1193
1194static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
1195							 struct at_xdmac_chan *atchan,
1196							 dma_addr_t dst_addr,
1197							 size_t len,
1198							 int value)
1199{
1200	struct at_xdmac_desc	*desc;
1201	unsigned long		flags;
1202	size_t			ublen;
1203	u32			dwidth;
 
1204	/*
1205	 * WARNING: The channel configuration is set here since there is no
1206	 * dmaengine_slave_config call in this case. Moreover we don't know the
1207	 * direction, it involves we can't dynamically set the source and dest
1208	 * interface so we have to use the same one. Only interface 0 allows EBI
1209	 * access. Hopefully we can access DDR through both ports (at least on
1210	 * SAMA5D4x), so we can use the same interface for source and dest,
1211	 * that solves the fact we don't know the direction.
1212	 * ERRATA: Even if useless for memory transfers, the PERID has to not
1213	 * match the one of another channel. If not, it could lead to spurious
1214	 * flag status.
1215	 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1216	 * Thus, no need to have the SIF/DIF interfaces here.
1217	 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1218	 * zero.
1219	 */
1220	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
1221					| AT_XDMAC_CC_DAM_UBS_AM
1222					| AT_XDMAC_CC_SAM_INCREMENTED_AM
1223					| AT_XDMAC_CC_MBSIZE_SIXTEEN
1224					| AT_XDMAC_CC_MEMSET_HW_MODE
1225					| AT_XDMAC_CC_TYPE_MEM_TRAN;
1226
1227	dwidth = at_xdmac_align_width(chan, dst_addr);
1228
1229	if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1230		dev_err(chan2dev(chan),
1231			"%s: Transfer too large, aborting...\n",
1232			__func__);
1233		return NULL;
1234	}
1235
1236	spin_lock_irqsave(&atchan->lock, flags);
1237	desc = at_xdmac_get_desc(atchan);
1238	spin_unlock_irqrestore(&atchan->lock, flags);
1239	if (!desc) {
1240		dev_err(chan2dev(chan), "can't get descriptor\n");
1241		return NULL;
1242	}
1243
1244	chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1245
 
 
 
1246	ublen = len >> dwidth;
1247
1248	desc->lld.mbr_da = dst_addr;
1249	desc->lld.mbr_ds = value;
 
 
 
1250	desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1251		| AT_XDMAC_MBR_UBC_NDEN
1252		| AT_XDMAC_MBR_UBC_NSEN
1253		| ublen;
1254	desc->lld.mbr_cfg = chan_cc;
1255
1256	dev_dbg(chan2dev(chan),
1257		"%s: lld: mbr_da=%pad, mbr_ds=0x%08x, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1258		__func__, &desc->lld.mbr_da, desc->lld.mbr_ds, desc->lld.mbr_ubc,
1259		desc->lld.mbr_cfg);
1260
1261	return desc;
1262}
1263
1264static struct dma_async_tx_descriptor *
1265at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
1266			 size_t len, unsigned long flags)
1267{
1268	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1269	struct at_xdmac_desc	*desc;
1270
1271	dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%zu, pattern=0x%x, flags=0x%lx\n",
1272		__func__, &dest, len, value, flags);
1273
1274	if (unlikely(!len))
1275		return NULL;
1276
1277	desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value);
1278	list_add_tail(&desc->desc_node, &desc->descs_list);
1279
1280	desc->tx_dma_desc.cookie = -EBUSY;
1281	desc->tx_dma_desc.flags = flags;
1282	desc->xfer_size = len;
1283
1284	return &desc->tx_dma_desc;
1285}
1286
1287static struct dma_async_tx_descriptor *
1288at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
1289			    unsigned int sg_len, int value,
1290			    unsigned long flags)
1291{
1292	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1293	struct at_xdmac_desc	*desc, *pdesc = NULL,
1294				*ppdesc = NULL, *first = NULL;
1295	struct scatterlist	*sg, *psg = NULL, *ppsg = NULL;
1296	size_t			stride = 0, pstride = 0, len = 0;
1297	int			i;
1298
1299	if (!sgl)
1300		return NULL;
1301
1302	dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n",
1303		__func__, sg_len, value, flags);
1304
1305	/* Prepare descriptors. */
1306	for_each_sg(sgl, sg, sg_len, i) {
1307		dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
1308			__func__, &sg_dma_address(sg), sg_dma_len(sg),
1309			value, flags);
1310		desc = at_xdmac_memset_create_desc(chan, atchan,
1311						   sg_dma_address(sg),
1312						   sg_dma_len(sg),
1313						   value);
1314		if (!desc && first)
1315			list_splice_init(&first->descs_list,
1316					 &atchan->free_descs_list);
1317
1318		if (!first)
1319			first = desc;
1320
1321		/* Update our strides */
1322		pstride = stride;
1323		if (psg)
1324			stride = sg_dma_address(sg) -
1325				(sg_dma_address(psg) + sg_dma_len(psg));
1326
1327		/*
1328		 * The scatterlist API gives us only the address and
1329		 * length of each elements.
1330		 *
1331		 * Unfortunately, we don't have the stride, which we
1332		 * will need to compute.
1333		 *
1334		 * That make us end up in a situation like this one:
1335		 *    len    stride    len    stride    len
1336		 * +-------+        +-------+        +-------+
1337		 * |  N-2  |        |  N-1  |        |   N   |
1338		 * +-------+        +-------+        +-------+
1339		 *
1340		 * We need all these three elements (N-2, N-1 and N)
1341		 * to actually take the decision on whether we need to
1342		 * queue N-1 or reuse N-2.
1343		 *
1344		 * We will only consider N if it is the last element.
1345		 */
1346		if (ppdesc && pdesc) {
1347			if ((stride == pstride) &&
1348			    (sg_dma_len(ppsg) == sg_dma_len(psg))) {
1349				dev_dbg(chan2dev(chan),
1350					"%s: desc 0x%p can be merged with desc 0x%p\n",
1351					__func__, pdesc, ppdesc);
1352
1353				/*
1354				 * Increment the block count of the
1355				 * N-2 descriptor
1356				 */
1357				at_xdmac_increment_block_count(chan, ppdesc);
1358				ppdesc->lld.mbr_dus = stride;
1359
1360				/*
1361				 * Put back the N-1 descriptor in the
1362				 * free descriptor list
1363				 */
1364				list_add_tail(&pdesc->desc_node,
1365					      &atchan->free_descs_list);
1366
1367				/*
1368				 * Make our N-1 descriptor pointer
1369				 * point to the N-2 since they were
1370				 * actually merged.
1371				 */
1372				pdesc = ppdesc;
1373
1374			/*
1375			 * Rule out the case where we don't have
1376			 * pstride computed yet (our second sg
1377			 * element)
1378			 *
1379			 * We also want to catch the case where there
1380			 * would be a negative stride,
1381			 */
1382			} else if (pstride ||
1383				   sg_dma_address(sg) < sg_dma_address(psg)) {
1384				/*
1385				 * Queue the N-1 descriptor after the
1386				 * N-2
1387				 */
1388				at_xdmac_queue_desc(chan, ppdesc, pdesc);
1389
1390				/*
1391				 * Add the N-1 descriptor to the list
1392				 * of the descriptors used for this
1393				 * transfer
1394				 */
1395				list_add_tail(&desc->desc_node,
1396					      &first->descs_list);
1397				dev_dbg(chan2dev(chan),
1398					"%s: add desc 0x%p to descs_list 0x%p\n",
1399					__func__, desc, first);
1400			}
1401		}
1402
1403		/*
1404		 * If we are the last element, just see if we have the
1405		 * same size than the previous element.
1406		 *
1407		 * If so, we can merge it with the previous descriptor
1408		 * since we don't care about the stride anymore.
1409		 */
1410		if ((i == (sg_len - 1)) &&
1411		    sg_dma_len(psg) == sg_dma_len(sg)) {
1412			dev_dbg(chan2dev(chan),
1413				"%s: desc 0x%p can be merged with desc 0x%p\n",
1414				__func__, desc, pdesc);
1415
1416			/*
1417			 * Increment the block count of the N-1
1418			 * descriptor
1419			 */
1420			at_xdmac_increment_block_count(chan, pdesc);
1421			pdesc->lld.mbr_dus = stride;
1422
1423			/*
1424			 * Put back the N descriptor in the free
1425			 * descriptor list
1426			 */
1427			list_add_tail(&desc->desc_node,
1428				      &atchan->free_descs_list);
1429		}
1430
1431		/* Update our descriptors */
1432		ppdesc = pdesc;
1433		pdesc = desc;
1434
1435		/* Update our scatter pointers */
1436		ppsg = psg;
1437		psg = sg;
1438
1439		len += sg_dma_len(sg);
1440	}
1441
1442	first->tx_dma_desc.cookie = -EBUSY;
1443	first->tx_dma_desc.flags = flags;
1444	first->xfer_size = len;
1445
1446	return &first->tx_dma_desc;
1447}
1448
1449static enum dma_status
1450at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1451		struct dma_tx_state *txstate)
1452{
1453	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1454	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1455	struct at_xdmac_desc	*desc, *_desc;
1456	struct list_head	*descs_list;
1457	enum dma_status		ret;
1458	int			residue, retry;
1459	u32			cur_nda, check_nda, cur_ubc, mask, value;
1460	u8			dwidth = 0;
1461	unsigned long		flags;
1462	bool			initd;
1463
1464	ret = dma_cookie_status(chan, cookie, txstate);
1465	if (ret == DMA_COMPLETE)
1466		return ret;
1467
1468	if (!txstate)
1469		return ret;
 
1470
1471	spin_lock_irqsave(&atchan->lock, flags);
1472
1473	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
1474
1475	/*
1476	 * If the transfer has not been started yet, don't need to compute the
1477	 * residue, it's the transfer length.
1478	 */
1479	if (!desc->active_xfer) {
1480		dma_set_residue(txstate, desc->xfer_size);
1481		goto spin_unlock;
1482	}
1483
1484	residue = desc->xfer_size;
1485	/*
1486	 * Flush FIFO: only relevant when the transfer is source peripheral
1487	 * synchronized. Flush is needed before reading CUBC because data in
1488	 * the FIFO are not reported by CUBC. Reporting a residue of the
1489	 * transfer length while we have data in FIFO can cause issue.
1490	 * Usecase: atmel USART has a timeout which means I have received
1491	 * characters but there is no more character received for a while. On
1492	 * timeout, it requests the residue. If the data are in the DMA FIFO,
1493	 * we will return a residue of the transfer length. It means no data
1494	 * received. If an application is waiting for these data, it will hang
1495	 * since we won't have another USART timeout without receiving new
1496	 * data.
1497	 */
1498	mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC;
1499	value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM;
1500	if ((desc->lld.mbr_cfg & mask) == value) {
1501		at_xdmac_write(atxdmac, atxdmac->layout->gswf, atchan->mask);
1502		while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1503			cpu_relax();
1504	}
1505
1506	/*
1507	 * The easiest way to compute the residue should be to pause the DMA
1508	 * but doing this can lead to miss some data as some devices don't
1509	 * have FIFO.
1510	 * We need to read several registers because:
1511	 * - DMA is running therefore a descriptor change is possible while
1512	 * reading these registers
1513	 * - When the block transfer is done, the value of the CUBC register
1514	 * is set to its initial value until the fetch of the next descriptor.
1515	 * This value will corrupt the residue calculation so we have to skip
1516	 * it.
1517	 *
1518	 * INITD --------                    ------------
1519	 *              |____________________|
1520	 *       _______________________  _______________
1521	 * NDA       @desc2             \/   @desc3
1522	 *       _______________________/\_______________
1523	 *       __________  ___________  _______________
1524	 * CUBC       0    \/ MAX desc1 \/  MAX desc2
1525	 *       __________/\___________/\_______________
1526	 *
1527	 * Since descriptors are aligned on 64 bits, we can assume that
1528	 * the update of NDA and CUBC is atomic.
1529	 * Memory barriers are used to ensure the read order of the registers.
1530	 * A max number of retries is set because unlikely it could never ends.
1531	 */
1532	for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
1533		check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1534		rmb();
1535		cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
1536		rmb();
1537		initd = !!(at_xdmac_chan_read(atchan, AT_XDMAC_CC) & AT_XDMAC_CC_INITD);
1538		rmb();
1539		cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1540		rmb();
1541
1542		if ((check_nda == cur_nda) && initd)
1543			break;
1544	}
1545
1546	if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
1547		ret = DMA_ERROR;
1548		goto spin_unlock;
1549	}
1550
1551	/*
1552	 * Flush FIFO: only relevant when the transfer is source peripheral
1553	 * synchronized. Another flush is needed here because CUBC is updated
1554	 * when the controller sends the data write command. It can lead to
1555	 * report data that are not written in the memory or the device. The
1556	 * FIFO flush ensures that data are really written.
1557	 */
1558	if ((desc->lld.mbr_cfg & mask) == value) {
1559		at_xdmac_write(atxdmac, atxdmac->layout->gswf, atchan->mask);
1560		while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1561			cpu_relax();
1562	}
1563
1564	/*
1565	 * Remove size of all microblocks already transferred and the current
1566	 * one. Then add the remaining size to transfer of the current
1567	 * microblock.
1568	 */
1569	descs_list = &desc->descs_list;
1570	list_for_each_entry_safe(desc, _desc, descs_list, desc_node) {
1571		dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg);
1572		residue -= (desc->lld.mbr_ubc & 0xffffff) << dwidth;
1573		if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda)
 
1574			break;
 
1575	}
1576	residue += cur_ubc << dwidth;
1577
1578	dma_set_residue(txstate, residue);
1579
1580	dev_dbg(chan2dev(chan),
1581		 "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n",
1582		 __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
1583
1584spin_unlock:
1585	spin_unlock_irqrestore(&atchan->lock, flags);
 
 
1586	return ret;
1587}
1588
1589/* Call must be protected by lock. */
1590static void at_xdmac_remove_xfer(struct at_xdmac_chan *atchan,
1591				    struct at_xdmac_desc *desc)
1592{
1593	dev_dbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1594
1595	/*
1596	 * Remove the transfer from the transfer list then move the transfer
1597	 * descriptors into the free descriptors list.
1598	 */
1599	list_del(&desc->xfer_node);
1600	list_splice_init(&desc->descs_list, &atchan->free_descs_list);
1601}
1602
1603static void at_xdmac_advance_work(struct at_xdmac_chan *atchan)
1604{
1605	struct at_xdmac_desc	*desc;
1606
1607	/*
1608	 * If channel is enabled, do nothing, advance_work will be triggered
1609	 * after the interruption.
1610	 */
1611	if (!at_xdmac_chan_is_enabled(atchan) && !list_empty(&atchan->xfers_list)) {
1612		desc = list_first_entry(&atchan->xfers_list,
1613					struct at_xdmac_desc,
1614					xfer_node);
1615		dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1616		if (!desc->active_xfer)
1617			at_xdmac_start_xfer(atchan, desc);
1618	}
1619}
1620
1621static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
1622{
1623	struct at_xdmac_desc		*desc;
1624	struct dma_async_tx_descriptor	*txd;
1625
1626	if (!list_empty(&atchan->xfers_list)) {
1627		desc = list_first_entry(&atchan->xfers_list,
1628					struct at_xdmac_desc, xfer_node);
1629		txd = &desc->tx_dma_desc;
1630
1631		if (txd->flags & DMA_PREP_INTERRUPT)
1632			dmaengine_desc_get_callback_invoke(txd, NULL);
1633	}
 
 
 
 
 
 
1634}
1635
 
1636static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
1637{
1638	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1639	struct at_xdmac_desc	*bad_desc;
 
 
 
 
 
1640
1641	/*
1642	 * The descriptor currently at the head of the active list is
1643	 * broken. Since we don't have any way to report errors, we'll
1644	 * just have to scream loudly and try to continue with other
1645	 * descriptors queued (if any).
1646	 */
1647	if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
1648		dev_err(chan2dev(&atchan->chan), "read bus error!!!");
1649	if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
1650		dev_err(chan2dev(&atchan->chan), "write bus error!!!");
1651	if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
1652		dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
1653
1654	spin_lock_irq(&atchan->lock);
1655
1656	/* Channel must be disabled first as it's not done automatically */
1657	at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1658	while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1659		cpu_relax();
1660
1661	bad_desc = list_first_entry(&atchan->xfers_list,
1662				    struct at_xdmac_desc,
1663				    xfer_node);
1664
1665	spin_unlock_irq(&atchan->lock);
1666
1667	/* Print bad descriptor's details if needed */
1668	dev_dbg(chan2dev(&atchan->chan),
1669		"%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
1670		__func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da,
1671		bad_desc->lld.mbr_ubc);
1672
 
 
 
1673	/* Then continue with usual descriptor management */
1674}
1675
1676static void at_xdmac_tasklet(struct tasklet_struct *t)
1677{
1678	struct at_xdmac_chan	*atchan = from_tasklet(atchan, t, tasklet);
 
1679	struct at_xdmac_desc	*desc;
 
1680	u32			error_mask;
1681
 
 
 
 
 
 
 
 
1682	dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
1683		__func__, atchan->irq_status);
1684
1685	error_mask = AT_XDMAC_CIS_RBEIS
1686		     | AT_XDMAC_CIS_WBEIS
1687		     | AT_XDMAC_CIS_ROIS;
1688
1689	if (at_xdmac_chan_is_cyclic(atchan)) {
1690		at_xdmac_handle_cyclic(atchan);
1691	} else if ((atchan->irq_status & AT_XDMAC_CIS_LIS)
1692		   || (atchan->irq_status & error_mask)) {
1693		struct dma_async_tx_descriptor  *txd;
1694
1695		if (atchan->irq_status & error_mask)
1696			at_xdmac_handle_error(atchan);
1697
1698		spin_lock_irq(&atchan->lock);
1699		desc = list_first_entry(&atchan->xfers_list,
1700					struct at_xdmac_desc,
1701					xfer_node);
1702		dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1703		if (!desc->active_xfer) {
1704			dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
1705			spin_unlock_irq(&atchan->lock);
1706			return;
1707		}
1708
1709		txd = &desc->tx_dma_desc;
 
1710
1711		at_xdmac_remove_xfer(atchan, desc);
 
 
 
 
1712		spin_unlock_irq(&atchan->lock);
 
 
1713
1714		dma_cookie_complete(txd);
1715		if (txd->flags & DMA_PREP_INTERRUPT)
1716			dmaengine_desc_get_callback_invoke(txd, NULL);
 
 
1717
1718		dma_run_dependencies(txd);
 
1719
1720		spin_lock_irq(&atchan->lock);
1721		at_xdmac_advance_work(atchan);
1722		spin_unlock_irq(&atchan->lock);
1723	}
 
 
 
 
 
 
 
 
 
 
1724}
1725
1726static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
1727{
1728	struct at_xdmac		*atxdmac = (struct at_xdmac *)dev_id;
1729	struct at_xdmac_chan	*atchan;
1730	u32			imr, status, pending;
1731	u32			chan_imr, chan_status;
1732	int			i, ret = IRQ_NONE;
1733
1734	do {
1735		imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1736		status = at_xdmac_read(atxdmac, AT_XDMAC_GIS);
1737		pending = status & imr;
1738
1739		dev_vdbg(atxdmac->dma.dev,
1740			 "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n",
1741			 __func__, status, imr, pending);
1742
1743		if (!pending)
1744			break;
1745
1746		/* We have to find which channel has generated the interrupt. */
1747		for (i = 0; i < atxdmac->dma.chancnt; i++) {
1748			if (!((1 << i) & pending))
1749				continue;
1750
1751			atchan = &atxdmac->chan[i];
1752			chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1753			chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
1754			atchan->irq_status = chan_status & chan_imr;
1755			dev_vdbg(atxdmac->dma.dev,
1756				 "%s: chan%d: imr=0x%x, status=0x%x\n",
1757				 __func__, i, chan_imr, chan_status);
1758			dev_vdbg(chan2dev(&atchan->chan),
1759				 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
1760				 __func__,
1761				 at_xdmac_chan_read(atchan, AT_XDMAC_CC),
1762				 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
1763				 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
1764				 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
1765				 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
1766				 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
1767
1768			if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
1769				at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1770
1771			tasklet_schedule(&atchan->tasklet);
1772			ret = IRQ_HANDLED;
1773		}
1774
1775	} while (pending);
1776
1777	return ret;
1778}
1779
1780static void at_xdmac_issue_pending(struct dma_chan *chan)
1781{
1782	struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1783	unsigned long flags;
1784
1785	dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__);
1786
1787	if (!at_xdmac_chan_is_cyclic(atchan)) {
1788		spin_lock_irqsave(&atchan->lock, flags);
1789		at_xdmac_advance_work(atchan);
1790		spin_unlock_irqrestore(&atchan->lock, flags);
1791	}
1792
1793	return;
1794}
1795
1796static int at_xdmac_device_config(struct dma_chan *chan,
1797				  struct dma_slave_config *config)
1798{
1799	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1800	int ret;
1801	unsigned long		flags;
1802
1803	dev_dbg(chan2dev(chan), "%s\n", __func__);
1804
1805	spin_lock_irqsave(&atchan->lock, flags);
1806	ret = at_xdmac_set_slave_config(chan, config);
1807	spin_unlock_irqrestore(&atchan->lock, flags);
1808
1809	return ret;
1810}
1811
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1812static int at_xdmac_device_pause(struct dma_chan *chan)
1813{
1814	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1815	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1816	unsigned long		flags;
 
1817
1818	dev_dbg(chan2dev(chan), "%s\n", __func__);
1819
1820	if (test_and_set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status))
1821		return 0;
1822
 
 
 
 
1823	spin_lock_irqsave(&atchan->lock, flags);
1824	at_xdmac_write(atxdmac, atxdmac->layout->grws, atchan->mask);
1825	while (at_xdmac_chan_read(atchan, AT_XDMAC_CC)
1826	       & (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP))
1827		cpu_relax();
 
1828	spin_unlock_irqrestore(&atchan->lock, flags);
1829
 
 
 
1830	return 0;
1831}
1832
 
 
 
 
 
 
 
 
 
 
 
1833static int at_xdmac_device_resume(struct dma_chan *chan)
1834{
1835	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1836	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1837	unsigned long		flags;
 
1838
1839	dev_dbg(chan2dev(chan), "%s\n", __func__);
1840
 
 
 
 
1841	spin_lock_irqsave(&atchan->lock, flags);
1842	if (!at_xdmac_chan_is_paused(atchan)) {
1843		spin_unlock_irqrestore(&atchan->lock, flags);
1844		return 0;
1845	}
 
 
 
1846
1847	at_xdmac_write(atxdmac, atxdmac->layout->grwr, atchan->mask);
1848	clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
 
 
1849	spin_unlock_irqrestore(&atchan->lock, flags);
 
 
1850
1851	return 0;
1852}
1853
1854static int at_xdmac_device_terminate_all(struct dma_chan *chan)
1855{
1856	struct at_xdmac_desc	*desc, *_desc;
1857	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1858	struct at_xdmac		*atxdmac = to_at_xdmac(atchan->chan.device);
1859	unsigned long		flags;
 
1860
1861	dev_dbg(chan2dev(chan), "%s\n", __func__);
1862
 
 
 
 
1863	spin_lock_irqsave(&atchan->lock, flags);
1864	at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1865	while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1866		cpu_relax();
1867
1868	/* Cancel all pending transfers. */
1869	list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node)
1870		at_xdmac_remove_xfer(atchan, desc);
 
 
 
 
 
 
 
 
 
 
 
 
1871
1872	clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
1873	clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
1874	spin_unlock_irqrestore(&atchan->lock, flags);
1875
 
 
 
1876	return 0;
1877}
1878
1879static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
1880{
1881	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1882	struct at_xdmac_desc	*desc;
1883	int			i;
1884
1885	if (at_xdmac_chan_is_enabled(atchan)) {
1886		dev_err(chan2dev(chan),
1887			"can't allocate channel resources (channel enabled)\n");
1888		return -EIO;
1889	}
1890
1891	if (!list_empty(&atchan->free_descs_list)) {
1892		dev_err(chan2dev(chan),
1893			"can't allocate channel resources (channel not free from a previous use)\n");
1894		return -EIO;
1895	}
1896
1897	for (i = 0; i < init_nr_desc_per_channel; i++) {
1898		desc = at_xdmac_alloc_desc(chan, GFP_KERNEL);
1899		if (!desc) {
 
 
 
 
 
1900			dev_warn(chan2dev(chan),
1901				"only %d descriptors have been allocated\n", i);
1902			break;
1903		}
1904		list_add_tail(&desc->desc_node, &atchan->free_descs_list);
1905	}
1906
1907	dma_cookie_init(chan);
1908
1909	dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
1910
1911	return i;
1912}
1913
1914static void at_xdmac_free_chan_resources(struct dma_chan *chan)
1915{
1916	struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1917	struct at_xdmac		*atxdmac = to_at_xdmac(chan->device);
1918	struct at_xdmac_desc	*desc, *_desc;
1919
1920	list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) {
1921		dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc);
1922		list_del(&desc->desc_node);
1923		dma_pool_free(atxdmac->at_xdmac_desc_pool, desc, desc->tx_dma_desc.phys);
1924	}
1925
1926	return;
1927}
1928
1929#ifdef CONFIG_PM
1930static int atmel_xdmac_prepare(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1931{
1932	struct at_xdmac		*atxdmac = dev_get_drvdata(dev);
1933	struct dma_chan		*chan, *_chan;
1934
1935	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1936		struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1937
1938		/* Wait for transfer completion, except in cyclic case. */
1939		if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan))
1940			return -EAGAIN;
1941	}
1942	return 0;
1943}
1944#else
1945#	define atmel_xdmac_prepare NULL
1946#endif
1947
1948#ifdef CONFIG_PM_SLEEP
1949static int atmel_xdmac_suspend(struct device *dev)
1950{
1951	struct at_xdmac		*atxdmac = dev_get_drvdata(dev);
1952	struct dma_chan		*chan, *_chan;
 
 
 
 
 
1953
1954	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1955		struct at_xdmac_chan	*atchan = to_at_xdmac_chan(chan);
1956
1957		atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
1958		if (at_xdmac_chan_is_cyclic(atchan)) {
1959			if (!at_xdmac_chan_is_paused(atchan))
1960				at_xdmac_device_pause(chan);
 
 
 
 
1961			atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1962			atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
1963			atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC);
1964		}
1965	}
1966	atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
 
1967
1968	at_xdmac_off(atxdmac);
 
 
1969	clk_disable_unprepare(atxdmac->clk);
 
1970	return 0;
1971}
1972
1973static int atmel_xdmac_resume(struct device *dev)
1974{
1975	struct at_xdmac		*atxdmac = dev_get_drvdata(dev);
1976	struct at_xdmac_chan	*atchan;
1977	struct dma_chan		*chan, *_chan;
1978	int			i;
1979	int ret;
1980
1981	ret = clk_prepare_enable(atxdmac->clk);
1982	if (ret)
1983		return ret;
1984
 
 
 
 
1985	/* Clear pending interrupts. */
1986	for (i = 0; i < atxdmac->dma.chancnt; i++) {
1987		atchan = &atxdmac->chan[i];
1988		while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
1989			cpu_relax();
1990	}
1991
1992	at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim);
1993	list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1994		atchan = to_at_xdmac_chan(chan);
 
1995		at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
1996		if (at_xdmac_chan_is_cyclic(atchan)) {
1997			if (at_xdmac_chan_is_paused(atchan))
1998				at_xdmac_device_resume(chan);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1999			at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
2000			at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
2001			at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim);
2002			wmb();
2003			at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
 
2004		}
2005	}
 
 
 
 
2006	return 0;
2007}
2008#endif /* CONFIG_PM_SLEEP */
2009
2010static void at_xdmac_axi_config(struct platform_device *pdev)
2011{
2012	struct at_xdmac	*atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2013	bool dev_m2m = false;
2014	u32 dma_requests;
2015
2016	if (!atxdmac->layout->axi_config)
2017		return; /* Not supported */
2018
2019	if (!of_property_read_u32(pdev->dev.of_node, "dma-requests",
2020				  &dma_requests)) {
2021		dev_info(&pdev->dev, "controller in mem2mem mode.\n");
2022		dev_m2m = true;
2023	}
2024
2025	if (dev_m2m) {
2026		at_xdmac_write(atxdmac, AT_XDMAC_GCFG, AT_XDMAC_GCFG_M2M);
2027		at_xdmac_write(atxdmac, AT_XDMAC_GWAC, AT_XDMAC_GWAC_M2M);
2028	} else {
2029		at_xdmac_write(atxdmac, AT_XDMAC_GCFG, AT_XDMAC_GCFG_P2M);
2030		at_xdmac_write(atxdmac, AT_XDMAC_GWAC, AT_XDMAC_GWAC_P2M);
2031	}
2032}
2033
2034static int at_xdmac_probe(struct platform_device *pdev)
2035{
2036	struct at_xdmac	*atxdmac;
2037	int		irq, size, nr_channels, i, ret;
2038	void __iomem	*base;
2039	u32		reg;
2040
2041	irq = platform_get_irq(pdev, 0);
2042	if (irq < 0)
2043		return irq;
2044
2045	base = devm_platform_ioremap_resource(pdev, 0);
2046	if (IS_ERR(base))
2047		return PTR_ERR(base);
2048
2049	/*
2050	 * Read number of xdmac channels, read helper function can't be used
2051	 * since atxdmac is not yet allocated and we need to know the number
2052	 * of channels to do the allocation.
2053	 */
2054	reg = readl_relaxed(base + AT_XDMAC_GTYPE);
2055	nr_channels = AT_XDMAC_NB_CH(reg);
2056	if (nr_channels > AT_XDMAC_MAX_CHAN) {
2057		dev_err(&pdev->dev, "invalid number of channels (%u)\n",
2058			nr_channels);
2059		return -EINVAL;
2060	}
2061
2062	size = sizeof(*atxdmac);
2063	size += nr_channels * sizeof(struct at_xdmac_chan);
2064	atxdmac = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
2065	if (!atxdmac) {
2066		dev_err(&pdev->dev, "can't allocate at_xdmac structure\n");
2067		return -ENOMEM;
2068	}
2069
2070	atxdmac->regs = base;
2071	atxdmac->irq = irq;
 
2072
2073	atxdmac->layout = of_device_get_match_data(&pdev->dev);
2074	if (!atxdmac->layout)
2075		return -ENODEV;
2076
2077	atxdmac->clk = devm_clk_get(&pdev->dev, "dma_clk");
2078	if (IS_ERR(atxdmac->clk)) {
2079		dev_err(&pdev->dev, "can't get dma_clk\n");
2080		return PTR_ERR(atxdmac->clk);
2081	}
2082
2083	/* Do not use dev res to prevent races with tasklet */
2084	ret = request_irq(atxdmac->irq, at_xdmac_interrupt, 0, "at_xdmac", atxdmac);
2085	if (ret) {
2086		dev_err(&pdev->dev, "can't request irq\n");
2087		return ret;
2088	}
2089
2090	ret = clk_prepare_enable(atxdmac->clk);
2091	if (ret) {
2092		dev_err(&pdev->dev, "can't prepare or enable clock\n");
2093		goto err_free_irq;
2094	}
2095
2096	atxdmac->at_xdmac_desc_pool =
2097		dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
2098				sizeof(struct at_xdmac_desc), 4, 0);
2099	if (!atxdmac->at_xdmac_desc_pool) {
2100		dev_err(&pdev->dev, "no memory for descriptors dma pool\n");
2101		ret = -ENOMEM;
2102		goto err_clk_disable;
2103	}
2104
2105	dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask);
2106	dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask);
2107	dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask);
2108	dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask);
2109	dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask);
2110	dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask);
2111	/*
2112	 * Without DMA_PRIVATE the driver is not able to allocate more than
2113	 * one channel, second allocation fails in private_candidate.
2114	 */
2115	dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask);
2116	atxdmac->dma.dev				= &pdev->dev;
2117	atxdmac->dma.device_alloc_chan_resources	= at_xdmac_alloc_chan_resources;
2118	atxdmac->dma.device_free_chan_resources		= at_xdmac_free_chan_resources;
2119	atxdmac->dma.device_tx_status			= at_xdmac_tx_status;
2120	atxdmac->dma.device_issue_pending		= at_xdmac_issue_pending;
2121	atxdmac->dma.device_prep_dma_cyclic		= at_xdmac_prep_dma_cyclic;
2122	atxdmac->dma.device_prep_interleaved_dma	= at_xdmac_prep_interleaved;
2123	atxdmac->dma.device_prep_dma_memcpy		= at_xdmac_prep_dma_memcpy;
2124	atxdmac->dma.device_prep_dma_memset		= at_xdmac_prep_dma_memset;
2125	atxdmac->dma.device_prep_dma_memset_sg		= at_xdmac_prep_dma_memset_sg;
2126	atxdmac->dma.device_prep_slave_sg		= at_xdmac_prep_slave_sg;
2127	atxdmac->dma.device_config			= at_xdmac_device_config;
2128	atxdmac->dma.device_pause			= at_xdmac_device_pause;
2129	atxdmac->dma.device_resume			= at_xdmac_device_resume;
2130	atxdmac->dma.device_terminate_all		= at_xdmac_device_terminate_all;
2131	atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2132	atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2133	atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
2134	atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
2135
2136	/* Disable all chans and interrupts. */
2137	at_xdmac_off(atxdmac);
 
 
 
 
 
2138
2139	/* Init channels. */
2140	INIT_LIST_HEAD(&atxdmac->dma.channels);
 
 
 
 
2141	for (i = 0; i < nr_channels; i++) {
2142		struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2143
2144		atchan->chan.device = &atxdmac->dma;
2145		list_add_tail(&atchan->chan.device_node,
2146			      &atxdmac->dma.channels);
2147
2148		atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, i);
2149		atchan->mask = 1 << i;
2150
2151		spin_lock_init(&atchan->lock);
2152		INIT_LIST_HEAD(&atchan->xfers_list);
2153		INIT_LIST_HEAD(&atchan->free_descs_list);
2154		tasklet_setup(&atchan->tasklet, at_xdmac_tasklet);
2155
2156		/* Clear pending interrupts. */
2157		while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2158			cpu_relax();
2159	}
2160	platform_set_drvdata(pdev, atxdmac);
2161
2162	ret = dma_async_device_register(&atxdmac->dma);
2163	if (ret) {
2164		dev_err(&pdev->dev, "fail to register DMA engine device\n");
2165		goto err_clk_disable;
2166	}
2167
2168	ret = of_dma_controller_register(pdev->dev.of_node,
2169					 at_xdmac_xlate, atxdmac);
2170	if (ret) {
2171		dev_err(&pdev->dev, "could not register of dma controller\n");
2172		goto err_dma_unregister;
2173	}
2174
2175	dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n",
2176		 nr_channels, atxdmac->regs);
2177
2178	at_xdmac_axi_config(pdev);
2179
 
 
 
2180	return 0;
2181
2182err_dma_unregister:
2183	dma_async_device_unregister(&atxdmac->dma);
 
 
 
 
 
2184err_clk_disable:
2185	clk_disable_unprepare(atxdmac->clk);
2186err_free_irq:
2187	free_irq(atxdmac->irq, atxdmac);
2188	return ret;
2189}
2190
2191static int at_xdmac_remove(struct platform_device *pdev)
2192{
2193	struct at_xdmac	*atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2194	int		i;
2195
2196	at_xdmac_off(atxdmac);
2197	of_dma_controller_free(pdev->dev.of_node);
2198	dma_async_device_unregister(&atxdmac->dma);
 
 
 
2199	clk_disable_unprepare(atxdmac->clk);
2200
2201	free_irq(atxdmac->irq, atxdmac);
2202
2203	for (i = 0; i < atxdmac->dma.chancnt; i++) {
2204		struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2205
2206		tasklet_kill(&atchan->tasklet);
2207		at_xdmac_free_chan_resources(&atchan->chan);
2208	}
2209
2210	return 0;
2211}
2212
2213static const struct dev_pm_ops atmel_xdmac_dev_pm_ops = {
2214	.prepare	= atmel_xdmac_prepare,
2215	SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume)
 
 
2216};
2217
2218static const struct of_device_id atmel_xdmac_dt_ids[] = {
2219	{
2220		.compatible = "atmel,sama5d4-dma",
2221		.data = &at_xdmac_sama5d4_layout,
2222	}, {
2223		.compatible = "microchip,sama7g5-dma",
2224		.data = &at_xdmac_sama7g5_layout,
2225	}, {
2226		/* sentinel */
2227	}
2228};
2229MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids);
2230
2231static struct platform_driver at_xdmac_driver = {
2232	.probe		= at_xdmac_probe,
2233	.remove		= at_xdmac_remove,
2234	.driver = {
2235		.name		= "at_xdmac",
2236		.of_match_table	= of_match_ptr(atmel_xdmac_dt_ids),
2237		.pm		= &atmel_xdmac_dev_pm_ops,
2238	}
2239};
2240
2241static int __init at_xdmac_init(void)
2242{
2243	return platform_driver_probe(&at_xdmac_driver, at_xdmac_probe);
2244}
2245subsys_initcall(at_xdmac_init);
 
 
 
 
 
 
2246
2247MODULE_DESCRIPTION("Atmel Extended DMA Controller driver");
2248MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
2249MODULE_LICENSE("GPL");