1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Driver for the Synopsys DesignWare AHB DMA Controller 4 * 5 * Copyright (C) 2005-2007 Atmel Corporation 6 * Copyright (C) 2010-2011 ST Microelectronics 7 * Copyright (C) 2016 Intel Corporation 8 */ 9 10 #include <linux/bitops.h> 11 #include <linux/interrupt.h> 12 #include <linux/dmaengine.h> 13 14 #include <linux/io-64-nonatomic-hi-lo.h> 15 16 #include "internal.h" 17 18 #define DW_DMA_MAX_NR_REQUESTS 16 19 20 /* flow controller */ 21 enum dw_dma_fc { 22 DW_DMA_FC_D_M2M, 23 DW_DMA_FC_D_M2P, 24 DW_DMA_FC_D_P2M, 25 DW_DMA_FC_D_P2P, 26 DW_DMA_FC_P_P2M, 27 DW_DMA_FC_SP_P2P, 28 DW_DMA_FC_P_M2P, 29 DW_DMA_FC_DP_P2P, 30 }; 31 32 /* 33 * Redefine this macro to handle differences between 32- and 64-bit 34 * addressing, big vs. little endian, etc. 35 */ 36 #define DW_REG(name) u32 name; u32 __pad_##name 37 38 /* Hardware register definitions. */ 39 struct dw_dma_chan_regs { 40 DW_REG(SAR); /* Source Address Register */ 41 DW_REG(DAR); /* Destination Address Register */ 42 DW_REG(LLP); /* Linked List Pointer */ 43 u32 CTL_LO; /* Control Register Low */ 44 u32 CTL_HI; /* Control Register High */ 45 DW_REG(SSTAT); 46 DW_REG(DSTAT); 47 DW_REG(SSTATAR); 48 DW_REG(DSTATAR); 49 u32 CFG_LO; /* Configuration Register Low */ 50 u32 CFG_HI; /* Configuration Register High */ 51 DW_REG(SGR); 52 DW_REG(DSR); 53 }; 54 55 struct dw_dma_irq_regs { 56 DW_REG(XFER); 57 DW_REG(BLOCK); 58 DW_REG(SRC_TRAN); 59 DW_REG(DST_TRAN); 60 DW_REG(ERROR); 61 }; 62 63 struct dw_dma_regs { 64 /* per-channel registers */ 65 struct dw_dma_chan_regs CHAN[DW_DMA_MAX_NR_CHANNELS]; 66 67 /* irq handling */ 68 struct dw_dma_irq_regs RAW; /* r */ 69 struct dw_dma_irq_regs STATUS; /* r (raw & mask) */ 70 struct dw_dma_irq_regs MASK; /* rw (set = irq enabled) */ 71 struct dw_dma_irq_regs CLEAR; /* w (ack, affects "raw") */ 72 73 DW_REG(STATUS_INT); /* r */ 74 75 /* software handshaking */ 76 DW_REG(REQ_SRC); 77 DW_REG(REQ_DST); 78 DW_REG(SGL_REQ_SRC); 79 DW_REG(SGL_REQ_DST); 80 DW_REG(LAST_SRC); 81 DW_REG(LAST_DST); 82 83 /* miscellaneous */ 84 DW_REG(CFG); 85 DW_REG(CH_EN); 86 DW_REG(ID); 87 DW_REG(TEST); 88 89 /* iDMA 32-bit support */ 90 DW_REG(CLASS_PRIORITY0); 91 DW_REG(CLASS_PRIORITY1); 92 93 /* optional encoded params, 0x3c8..0x3f7 */ 94 u32 __reserved; 95 96 /* per-channel configuration registers */ 97 u32 DWC_PARAMS[DW_DMA_MAX_NR_CHANNELS]; 98 u32 MULTI_BLK_TYPE; 99 u32 MAX_BLK_SIZE; 100 101 /* top-level parameters */ 102 u32 DW_PARAMS; 103 104 /* component ID */ 105 u32 COMP_TYPE; 106 u32 COMP_VERSION; 107 108 /* iDMA 32-bit support */ 109 DW_REG(FIFO_PARTITION0); 110 DW_REG(FIFO_PARTITION1); 111 112 DW_REG(SAI_ERR); 113 DW_REG(GLOBAL_CFG); 114 }; 115 116 /* Bitfields in DW_PARAMS */ 117 #define DW_PARAMS_NR_CHAN 8 /* number of channels */ 118 #define DW_PARAMS_NR_MASTER 11 /* number of AHB masters */ 119 #define DW_PARAMS_DATA_WIDTH(n) (15 + 2 * (n)) 120 #define DW_PARAMS_DATA_WIDTH1 15 /* master 1 data width */ 121 #define DW_PARAMS_DATA_WIDTH2 17 /* master 2 data width */ 122 #define DW_PARAMS_DATA_WIDTH3 19 /* master 3 data width */ 123 #define DW_PARAMS_DATA_WIDTH4 21 /* master 4 data width */ 124 #define DW_PARAMS_EN 28 /* encoded parameters */ 125 126 /* Bitfields in DWC_PARAMS */ 127 #define DWC_PARAMS_MBLK_EN 11 /* multi block transfer */ 128 #define DWC_PARAMS_HC_LLP 13 /* set LLP register to zero */ 129 #define DWC_PARAMS_MSIZE 16 /* max group transaction size */ 130 131 /* bursts size */ 132 enum dw_dma_msize { 133 DW_DMA_MSIZE_1, 134 DW_DMA_MSIZE_4, 135 DW_DMA_MSIZE_8, 136 DW_DMA_MSIZE_16, 137 DW_DMA_MSIZE_32, 138 DW_DMA_MSIZE_64, 139 DW_DMA_MSIZE_128, 140 DW_DMA_MSIZE_256, 141 }; 142 143 /* Bitfields in LLP */ 144 #define DWC_LLP_LMS(x) ((x) & 3) /* list master select */ 145 #define DWC_LLP_LOC(x) ((x) & ~3) /* next lli */ 146 147 /* Bitfields in CTL_LO */ 148 #define DWC_CTLL_INT_EN (1 << 0) /* irqs enabled? */ 149 #define DWC_CTLL_DST_WIDTH(n) ((n)<<1) /* bytes per element */ 150 #define DWC_CTLL_SRC_WIDTH(n) ((n)<<4) 151 #define DWC_CTLL_DST_INC (0<<7) /* DAR update/not */ 152 #define DWC_CTLL_DST_DEC (1<<7) 153 #define DWC_CTLL_DST_FIX (2<<7) 154 #define DWC_CTLL_SRC_INC (0<<9) /* SAR update/not */ 155 #define DWC_CTLL_SRC_DEC (1<<9) 156 #define DWC_CTLL_SRC_FIX (2<<9) 157 #define DWC_CTLL_DST_MSIZE(n) ((n)<<11) /* burst, #elements */ 158 #define DWC_CTLL_SRC_MSIZE(n) ((n)<<14) 159 #define DWC_CTLL_S_GATH_EN (1 << 17) /* src gather, !FIX */ 160 #define DWC_CTLL_D_SCAT_EN (1 << 18) /* dst scatter, !FIX */ 161 #define DWC_CTLL_FC(n) ((n) << 20) 162 #define DWC_CTLL_FC_M2M (0 << 20) /* mem-to-mem */ 163 #define DWC_CTLL_FC_M2P (1 << 20) /* mem-to-periph */ 164 #define DWC_CTLL_FC_P2M (2 << 20) /* periph-to-mem */ 165 #define DWC_CTLL_FC_P2P (3 << 20) /* periph-to-periph */ 166 /* plus 4 transfer types for peripheral-as-flow-controller */ 167 #define DWC_CTLL_DMS(n) ((n)<<23) /* dst master select */ 168 #define DWC_CTLL_SMS(n) ((n)<<25) /* src master select */ 169 #define DWC_CTLL_LLP_D_EN (1 << 27) /* dest block chain */ 170 #define DWC_CTLL_LLP_S_EN (1 << 28) /* src block chain */ 171 172 /* Bitfields in CTL_HI */ 173 #define DWC_CTLH_BLOCK_TS_MASK GENMASK(11, 0) 174 #define DWC_CTLH_BLOCK_TS(x) ((x) & DWC_CTLH_BLOCK_TS_MASK) 175 #define DWC_CTLH_DONE (1 << 12) 176 177 /* Bitfields in CFG_LO */ 178 #define DWC_CFGL_CH_PRIOR_MASK (0x7 << 5) /* priority mask */ 179 #define DWC_CFGL_CH_PRIOR(x) ((x) << 5) /* priority */ 180 #define DWC_CFGL_CH_SUSP (1 << 8) /* pause xfer */ 181 #define DWC_CFGL_FIFO_EMPTY (1 << 9) /* pause xfer */ 182 #define DWC_CFGL_HS_DST (1 << 10) /* handshake w/dst */ 183 #define DWC_CFGL_HS_SRC (1 << 11) /* handshake w/src */ 184 #define DWC_CFGL_LOCK_CH_XFER (0 << 12) /* scope of LOCK_CH */ 185 #define DWC_CFGL_LOCK_CH_BLOCK (1 << 12) 186 #define DWC_CFGL_LOCK_CH_XACT (2 << 12) 187 #define DWC_CFGL_LOCK_BUS_XFER (0 << 14) /* scope of LOCK_BUS */ 188 #define DWC_CFGL_LOCK_BUS_BLOCK (1 << 14) 189 #define DWC_CFGL_LOCK_BUS_XACT (2 << 14) 190 #define DWC_CFGL_LOCK_CH (1 << 15) /* channel lockout */ 191 #define DWC_CFGL_LOCK_BUS (1 << 16) /* busmaster lockout */ 192 #define DWC_CFGL_HS_DST_POL (1 << 18) /* dst handshake active low */ 193 #define DWC_CFGL_HS_SRC_POL (1 << 19) /* src handshake active low */ 194 #define DWC_CFGL_MAX_BURST(x) ((x) << 20) 195 #define DWC_CFGL_RELOAD_SAR (1 << 30) 196 #define DWC_CFGL_RELOAD_DAR (1 << 31) 197 198 /* Bitfields in CFG_HI */ 199 #define DWC_CFGH_FCMODE (1 << 0) 200 #define DWC_CFGH_FIFO_MODE (1 << 1) 201 #define DWC_CFGH_PROTCTL(x) ((x) << 2) 202 #define DWC_CFGH_PROTCTL_DATA (0 << 2) /* data access - always set */ 203 #define DWC_CFGH_PROTCTL_PRIV (1 << 2) /* privileged -> AHB HPROT[1] */ 204 #define DWC_CFGH_PROTCTL_BUFFER (2 << 2) /* bufferable -> AHB HPROT[2] */ 205 #define DWC_CFGH_PROTCTL_CACHE (4 << 2) /* cacheable -> AHB HPROT[3] */ 206 #define DWC_CFGH_DS_UPD_EN (1 << 5) 207 #define DWC_CFGH_SS_UPD_EN (1 << 6) 208 #define DWC_CFGH_SRC_PER(x) ((x) << 7) 209 #define DWC_CFGH_DST_PER(x) ((x) << 11) 210 211 /* Bitfields in SGR */ 212 #define DWC_SGR_SGI(x) ((x) << 0) 213 #define DWC_SGR_SGC(x) ((x) << 20) 214 215 /* Bitfields in DSR */ 216 #define DWC_DSR_DSI(x) ((x) << 0) 217 #define DWC_DSR_DSC(x) ((x) << 20) 218 219 /* Bitfields in CFG */ 220 #define DW_CFG_DMA_EN (1 << 0) 221 222 /* iDMA 32-bit support */ 223 224 /* bursts size */ 225 enum idma32_msize { 226 IDMA32_MSIZE_1, 227 IDMA32_MSIZE_2, 228 IDMA32_MSIZE_4, 229 IDMA32_MSIZE_8, 230 IDMA32_MSIZE_16, 231 IDMA32_MSIZE_32, 232 }; 233 234 /* Bitfields in CTL_HI */ 235 #define IDMA32C_CTLH_BLOCK_TS_MASK GENMASK(16, 0) 236 #define IDMA32C_CTLH_BLOCK_TS(x) ((x) & IDMA32C_CTLH_BLOCK_TS_MASK) 237 #define IDMA32C_CTLH_DONE (1 << 17) 238 239 /* Bitfields in CFG_LO */ 240 #define IDMA32C_CFGL_DST_BURST_ALIGN (1 << 0) /* dst burst align */ 241 #define IDMA32C_CFGL_SRC_BURST_ALIGN (1 << 1) /* src burst align */ 242 #define IDMA32C_CFGL_CH_DRAIN (1 << 10) /* drain FIFO */ 243 #define IDMA32C_CFGL_DST_OPT_BL (1 << 20) /* optimize dst burst length */ 244 #define IDMA32C_CFGL_SRC_OPT_BL (1 << 21) /* optimize src burst length */ 245 246 /* Bitfields in CFG_HI */ 247 #define IDMA32C_CFGH_SRC_PER(x) ((x) << 0) 248 #define IDMA32C_CFGH_DST_PER(x) ((x) << 4) 249 #define IDMA32C_CFGH_RD_ISSUE_THD(x) ((x) << 8) 250 #define IDMA32C_CFGH_RW_ISSUE_THD(x) ((x) << 18) 251 #define IDMA32C_CFGH_SRC_PER_EXT(x) ((x) << 28) /* src peripheral extension */ 252 #define IDMA32C_CFGH_DST_PER_EXT(x) ((x) << 30) /* dst peripheral extension */ 253 254 /* Bitfields in FIFO_PARTITION */ 255 #define IDMA32C_FP_PSIZE_CH0(x) ((x) << 0) 256 #define IDMA32C_FP_PSIZE_CH1(x) ((x) << 13) 257 #define IDMA32C_FP_UPDATE (1 << 26) 258 259 enum dw_dmac_flags { 260 DW_DMA_IS_CYCLIC = 0, 261 DW_DMA_IS_SOFT_LLP = 1, 262 DW_DMA_IS_PAUSED = 2, 263 DW_DMA_IS_INITIALIZED = 3, 264 }; 265 266 struct dw_dma_chan { 267 struct dma_chan chan; 268 void __iomem *ch_regs; 269 u8 mask; 270 u8 priority; 271 enum dma_transfer_direction direction; 272 273 /* software emulation of the LLP transfers */ 274 struct list_head *tx_node_active; 275 276 spinlock_t lock; 277 278 /* these other elements are all protected by lock */ 279 unsigned long flags; 280 struct list_head active_list; 281 struct list_head queue; 282 283 unsigned int descs_allocated; 284 285 /* hardware configuration */ 286 unsigned int block_size; 287 bool nollp; 288 u32 max_burst; 289 290 /* custom slave configuration */ 291 struct dw_dma_slave dws; 292 293 /* configuration passed via .device_config */ 294 struct dma_slave_config dma_sconfig; 295 }; 296 297 static inline struct dw_dma_chan_regs __iomem * 298 __dwc_regs(struct dw_dma_chan *dwc) 299 { 300 return dwc->ch_regs; 301 } 302 303 #define channel_readl(dwc, name) \ 304 readl(&(__dwc_regs(dwc)->name)) 305 #define channel_writel(dwc, name, val) \ 306 writel((val), &(__dwc_regs(dwc)->name)) 307 308 static inline struct dw_dma_chan *to_dw_dma_chan(struct dma_chan *chan) 309 { 310 return container_of(chan, struct dw_dma_chan, chan); 311 } 312 313 struct dw_dma { 314 struct dma_device dma; 315 char name[20]; 316 void __iomem *regs; 317 struct dma_pool *desc_pool; 318 struct tasklet_struct tasklet; 319 320 /* channels */ 321 struct dw_dma_chan *chan; 322 u8 all_chan_mask; 323 u8 in_use; 324 325 /* Channel operations */ 326 void (*initialize_chan)(struct dw_dma_chan *dwc); 327 void (*suspend_chan)(struct dw_dma_chan *dwc, bool drain); 328 void (*resume_chan)(struct dw_dma_chan *dwc, bool drain); 329 u32 (*prepare_ctllo)(struct dw_dma_chan *dwc); 330 u32 (*bytes2block)(struct dw_dma_chan *dwc, size_t bytes, 331 unsigned int width, size_t *len); 332 size_t (*block2bytes)(struct dw_dma_chan *dwc, u32 block, u32 width); 333 334 /* Device operations */ 335 void (*set_device_name)(struct dw_dma *dw, int id); 336 void (*disable)(struct dw_dma *dw); 337 void (*enable)(struct dw_dma *dw); 338 339 /* platform data */ 340 struct dw_dma_platform_data *pdata; 341 }; 342 343 static inline struct dw_dma_regs __iomem *__dw_regs(struct dw_dma *dw) 344 { 345 return dw->regs; 346 } 347 348 #define dma_readl(dw, name) \ 349 readl(&(__dw_regs(dw)->name)) 350 #define dma_writel(dw, name, val) \ 351 writel((val), &(__dw_regs(dw)->name)) 352 353 #define idma32_readq(dw, name) \ 354 hi_lo_readq(&(__dw_regs(dw)->name)) 355 #define idma32_writeq(dw, name, val) \ 356 hi_lo_writeq((val), &(__dw_regs(dw)->name)) 357 358 #define channel_set_bit(dw, reg, mask) \ 359 dma_writel(dw, reg, ((mask) << 8) | (mask)) 360 #define channel_clear_bit(dw, reg, mask) \ 361 dma_writel(dw, reg, ((mask) << 8) | 0) 362 363 static inline struct dw_dma *to_dw_dma(struct dma_device *ddev) 364 { 365 return container_of(ddev, struct dw_dma, dma); 366 } 367 368 /* LLI == Linked List Item; a.k.a. DMA block descriptor */ 369 struct dw_lli { 370 /* values that are not changed by hardware */ 371 __le32 sar; 372 __le32 dar; 373 __le32 llp; /* chain to next lli */ 374 __le32 ctllo; 375 /* values that may get written back: */ 376 __le32 ctlhi; 377 /* sstat and dstat can snapshot peripheral register state. 378 * silicon config may discard either or both... 379 */ 380 __le32 sstat; 381 __le32 dstat; 382 }; 383 384 struct dw_desc { 385 /* FIRST values the hardware uses */ 386 struct dw_lli lli; 387 388 #define lli_set(d, reg, v) ((d)->lli.reg |= cpu_to_le32(v)) 389 #define lli_clear(d, reg, v) ((d)->lli.reg &= ~cpu_to_le32(v)) 390 #define lli_read(d, reg) le32_to_cpu((d)->lli.reg) 391 #define lli_write(d, reg, v) ((d)->lli.reg = cpu_to_le32(v)) 392 393 /* THEN values for driver housekeeping */ 394 struct list_head desc_node; 395 struct list_head tx_list; 396 struct dma_async_tx_descriptor txd; 397 size_t len; 398 size_t total_len; 399 u32 residue; 400 }; 401 402 #define to_dw_desc(h) list_entry(h, struct dw_desc, desc_node) 403 404 static inline struct dw_desc * 405 txd_to_dw_desc(struct dma_async_tx_descriptor *txd) 406 { 407 return container_of(txd, struct dw_desc, txd); 408 } 409