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