1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved. 4 */ 5 /* 6 * QCOM BAM DMA engine driver 7 * 8 * QCOM BAM DMA blocks are distributed amongst a number of the on-chip 9 * peripherals on the MSM 8x74. The configuration of the channels are dependent 10 * on the way they are hard wired to that specific peripheral. The peripheral 11 * device tree entries specify the configuration of each channel. 12 * 13 * The DMA controller requires the use of external memory for storage of the 14 * hardware descriptors for each channel. The descriptor FIFO is accessed as a 15 * circular buffer and operations are managed according to the offset within the 16 * FIFO. After pipe/channel reset, all of the pipe registers and internal state 17 * are back to defaults. 18 * 19 * During DMA operations, we write descriptors to the FIFO, being careful to 20 * handle wrapping and then write the last FIFO offset to that channel's 21 * P_EVNT_REG register to kick off the transaction. The P_SW_OFSTS register 22 * indicates the current FIFO offset that is being processed, so there is some 23 * indication of where the hardware is currently working. 24 */ 25 26 #include <linux/kernel.h> 27 #include <linux/io.h> 28 #include <linux/init.h> 29 #include <linux/slab.h> 30 #include <linux/module.h> 31 #include <linux/interrupt.h> 32 #include <linux/dma-mapping.h> 33 #include <linux/scatterlist.h> 34 #include <linux/device.h> 35 #include <linux/platform_device.h> 36 #include <linux/of.h> 37 #include <linux/of_address.h> 38 #include <linux/of_irq.h> 39 #include <linux/of_dma.h> 40 #include <linux/circ_buf.h> 41 #include <linux/clk.h> 42 #include <linux/dmaengine.h> 43 #include <linux/pm_runtime.h> 44 45 #include "../dmaengine.h" 46 #include "../virt-dma.h" 47 48 struct bam_desc_hw { 49 __le32 addr; /* Buffer physical address */ 50 __le16 size; /* Buffer size in bytes */ 51 __le16 flags; 52 }; 53 54 #define BAM_DMA_AUTOSUSPEND_DELAY 100 55 56 #define DESC_FLAG_INT BIT(15) 57 #define DESC_FLAG_EOT BIT(14) 58 #define DESC_FLAG_EOB BIT(13) 59 #define DESC_FLAG_NWD BIT(12) 60 #define DESC_FLAG_CMD BIT(11) 61 62 struct bam_async_desc { 63 struct virt_dma_desc vd; 64 65 u32 num_desc; 66 u32 xfer_len; 67 68 /* transaction flags, EOT|EOB|NWD */ 69 u16 flags; 70 71 struct bam_desc_hw *curr_desc; 72 73 /* list node for the desc in the bam_chan list of descriptors */ 74 struct list_head desc_node; 75 enum dma_transfer_direction dir; 76 size_t length; 77 struct bam_desc_hw desc[] __counted_by(num_desc); 78 }; 79 80 enum bam_reg { 81 BAM_CTRL, 82 BAM_REVISION, 83 BAM_NUM_PIPES, 84 BAM_DESC_CNT_TRSHLD, 85 BAM_IRQ_SRCS, 86 BAM_IRQ_SRCS_MSK, 87 BAM_IRQ_SRCS_UNMASKED, 88 BAM_IRQ_STTS, 89 BAM_IRQ_CLR, 90 BAM_IRQ_EN, 91 BAM_CNFG_BITS, 92 BAM_IRQ_SRCS_EE, 93 BAM_IRQ_SRCS_MSK_EE, 94 BAM_P_CTRL, 95 BAM_P_RST, 96 BAM_P_HALT, 97 BAM_P_IRQ_STTS, 98 BAM_P_IRQ_CLR, 99 BAM_P_IRQ_EN, 100 BAM_P_EVNT_DEST_ADDR, 101 BAM_P_EVNT_REG, 102 BAM_P_SW_OFSTS, 103 BAM_P_DATA_FIFO_ADDR, 104 BAM_P_DESC_FIFO_ADDR, 105 BAM_P_EVNT_GEN_TRSHLD, 106 BAM_P_FIFO_SIZES, 107 }; 108 109 struct reg_offset_data { 110 u32 base_offset; 111 unsigned int pipe_mult, evnt_mult, ee_mult; 112 }; 113 114 static const struct reg_offset_data bam_v1_3_reg_info[] = { 115 [BAM_CTRL] = { 0x0F80, 0x00, 0x00, 0x00 }, 116 [BAM_REVISION] = { 0x0F84, 0x00, 0x00, 0x00 }, 117 [BAM_NUM_PIPES] = { 0x0FBC, 0x00, 0x00, 0x00 }, 118 [BAM_DESC_CNT_TRSHLD] = { 0x0F88, 0x00, 0x00, 0x00 }, 119 [BAM_IRQ_SRCS] = { 0x0F8C, 0x00, 0x00, 0x00 }, 120 [BAM_IRQ_SRCS_MSK] = { 0x0F90, 0x00, 0x00, 0x00 }, 121 [BAM_IRQ_SRCS_UNMASKED] = { 0x0FB0, 0x00, 0x00, 0x00 }, 122 [BAM_IRQ_STTS] = { 0x0F94, 0x00, 0x00, 0x00 }, 123 [BAM_IRQ_CLR] = { 0x0F98, 0x00, 0x00, 0x00 }, 124 [BAM_IRQ_EN] = { 0x0F9C, 0x00, 0x00, 0x00 }, 125 [BAM_CNFG_BITS] = { 0x0FFC, 0x00, 0x00, 0x00 }, 126 [BAM_IRQ_SRCS_EE] = { 0x1800, 0x00, 0x00, 0x80 }, 127 [BAM_IRQ_SRCS_MSK_EE] = { 0x1804, 0x00, 0x00, 0x80 }, 128 [BAM_P_CTRL] = { 0x0000, 0x80, 0x00, 0x00 }, 129 [BAM_P_RST] = { 0x0004, 0x80, 0x00, 0x00 }, 130 [BAM_P_HALT] = { 0x0008, 0x80, 0x00, 0x00 }, 131 [BAM_P_IRQ_STTS] = { 0x0010, 0x80, 0x00, 0x00 }, 132 [BAM_P_IRQ_CLR] = { 0x0014, 0x80, 0x00, 0x00 }, 133 [BAM_P_IRQ_EN] = { 0x0018, 0x80, 0x00, 0x00 }, 134 [BAM_P_EVNT_DEST_ADDR] = { 0x102C, 0x00, 0x40, 0x00 }, 135 [BAM_P_EVNT_REG] = { 0x1018, 0x00, 0x40, 0x00 }, 136 [BAM_P_SW_OFSTS] = { 0x1000, 0x00, 0x40, 0x00 }, 137 [BAM_P_DATA_FIFO_ADDR] = { 0x1024, 0x00, 0x40, 0x00 }, 138 [BAM_P_DESC_FIFO_ADDR] = { 0x101C, 0x00, 0x40, 0x00 }, 139 [BAM_P_EVNT_GEN_TRSHLD] = { 0x1028, 0x00, 0x40, 0x00 }, 140 [BAM_P_FIFO_SIZES] = { 0x1020, 0x00, 0x40, 0x00 }, 141 }; 142 143 static const struct reg_offset_data bam_v1_4_reg_info[] = { 144 [BAM_CTRL] = { 0x0000, 0x00, 0x00, 0x00 }, 145 [BAM_REVISION] = { 0x0004, 0x00, 0x00, 0x00 }, 146 [BAM_NUM_PIPES] = { 0x003C, 0x00, 0x00, 0x00 }, 147 [BAM_DESC_CNT_TRSHLD] = { 0x0008, 0x00, 0x00, 0x00 }, 148 [BAM_IRQ_SRCS] = { 0x000C, 0x00, 0x00, 0x00 }, 149 [BAM_IRQ_SRCS_MSK] = { 0x0010, 0x00, 0x00, 0x00 }, 150 [BAM_IRQ_SRCS_UNMASKED] = { 0x0030, 0x00, 0x00, 0x00 }, 151 [BAM_IRQ_STTS] = { 0x0014, 0x00, 0x00, 0x00 }, 152 [BAM_IRQ_CLR] = { 0x0018, 0x00, 0x00, 0x00 }, 153 [BAM_IRQ_EN] = { 0x001C, 0x00, 0x00, 0x00 }, 154 [BAM_CNFG_BITS] = { 0x007C, 0x00, 0x00, 0x00 }, 155 [BAM_IRQ_SRCS_EE] = { 0x0800, 0x00, 0x00, 0x80 }, 156 [BAM_IRQ_SRCS_MSK_EE] = { 0x0804, 0x00, 0x00, 0x80 }, 157 [BAM_P_CTRL] = { 0x1000, 0x1000, 0x00, 0x00 }, 158 [BAM_P_RST] = { 0x1004, 0x1000, 0x00, 0x00 }, 159 [BAM_P_HALT] = { 0x1008, 0x1000, 0x00, 0x00 }, 160 [BAM_P_IRQ_STTS] = { 0x1010, 0x1000, 0x00, 0x00 }, 161 [BAM_P_IRQ_CLR] = { 0x1014, 0x1000, 0x00, 0x00 }, 162 [BAM_P_IRQ_EN] = { 0x1018, 0x1000, 0x00, 0x00 }, 163 [BAM_P_EVNT_DEST_ADDR] = { 0x182C, 0x00, 0x1000, 0x00 }, 164 [BAM_P_EVNT_REG] = { 0x1818, 0x00, 0x1000, 0x00 }, 165 [BAM_P_SW_OFSTS] = { 0x1800, 0x00, 0x1000, 0x00 }, 166 [BAM_P_DATA_FIFO_ADDR] = { 0x1824, 0x00, 0x1000, 0x00 }, 167 [BAM_P_DESC_FIFO_ADDR] = { 0x181C, 0x00, 0x1000, 0x00 }, 168 [BAM_P_EVNT_GEN_TRSHLD] = { 0x1828, 0x00, 0x1000, 0x00 }, 169 [BAM_P_FIFO_SIZES] = { 0x1820, 0x00, 0x1000, 0x00 }, 170 }; 171 172 static const struct reg_offset_data bam_v1_7_reg_info[] = { 173 [BAM_CTRL] = { 0x00000, 0x00, 0x00, 0x00 }, 174 [BAM_REVISION] = { 0x01000, 0x00, 0x00, 0x00 }, 175 [BAM_NUM_PIPES] = { 0x01008, 0x00, 0x00, 0x00 }, 176 [BAM_DESC_CNT_TRSHLD] = { 0x00008, 0x00, 0x00, 0x00 }, 177 [BAM_IRQ_SRCS] = { 0x03010, 0x00, 0x00, 0x00 }, 178 [BAM_IRQ_SRCS_MSK] = { 0x03014, 0x00, 0x00, 0x00 }, 179 [BAM_IRQ_SRCS_UNMASKED] = { 0x03018, 0x00, 0x00, 0x00 }, 180 [BAM_IRQ_STTS] = { 0x00014, 0x00, 0x00, 0x00 }, 181 [BAM_IRQ_CLR] = { 0x00018, 0x00, 0x00, 0x00 }, 182 [BAM_IRQ_EN] = { 0x0001C, 0x00, 0x00, 0x00 }, 183 [BAM_CNFG_BITS] = { 0x0007C, 0x00, 0x00, 0x00 }, 184 [BAM_IRQ_SRCS_EE] = { 0x03000, 0x00, 0x00, 0x1000 }, 185 [BAM_IRQ_SRCS_MSK_EE] = { 0x03004, 0x00, 0x00, 0x1000 }, 186 [BAM_P_CTRL] = { 0x13000, 0x1000, 0x00, 0x00 }, 187 [BAM_P_RST] = { 0x13004, 0x1000, 0x00, 0x00 }, 188 [BAM_P_HALT] = { 0x13008, 0x1000, 0x00, 0x00 }, 189 [BAM_P_IRQ_STTS] = { 0x13010, 0x1000, 0x00, 0x00 }, 190 [BAM_P_IRQ_CLR] = { 0x13014, 0x1000, 0x00, 0x00 }, 191 [BAM_P_IRQ_EN] = { 0x13018, 0x1000, 0x00, 0x00 }, 192 [BAM_P_EVNT_DEST_ADDR] = { 0x1382C, 0x00, 0x1000, 0x00 }, 193 [BAM_P_EVNT_REG] = { 0x13818, 0x00, 0x1000, 0x00 }, 194 [BAM_P_SW_OFSTS] = { 0x13800, 0x00, 0x1000, 0x00 }, 195 [BAM_P_DATA_FIFO_ADDR] = { 0x13824, 0x00, 0x1000, 0x00 }, 196 [BAM_P_DESC_FIFO_ADDR] = { 0x1381C, 0x00, 0x1000, 0x00 }, 197 [BAM_P_EVNT_GEN_TRSHLD] = { 0x13828, 0x00, 0x1000, 0x00 }, 198 [BAM_P_FIFO_SIZES] = { 0x13820, 0x00, 0x1000, 0x00 }, 199 }; 200 201 /* BAM CTRL */ 202 #define BAM_SW_RST BIT(0) 203 #define BAM_EN BIT(1) 204 #define BAM_EN_ACCUM BIT(4) 205 #define BAM_TESTBUS_SEL_SHIFT 5 206 #define BAM_TESTBUS_SEL_MASK 0x3F 207 #define BAM_DESC_CACHE_SEL_SHIFT 13 208 #define BAM_DESC_CACHE_SEL_MASK 0x3 209 #define BAM_CACHED_DESC_STORE BIT(15) 210 #define IBC_DISABLE BIT(16) 211 212 /* BAM REVISION */ 213 #define REVISION_SHIFT 0 214 #define REVISION_MASK 0xFF 215 #define NUM_EES_SHIFT 8 216 #define NUM_EES_MASK 0xF 217 #define CE_BUFFER_SIZE BIT(13) 218 #define AXI_ACTIVE BIT(14) 219 #define USE_VMIDMT BIT(15) 220 #define SECURED BIT(16) 221 #define BAM_HAS_NO_BYPASS BIT(17) 222 #define HIGH_FREQUENCY_BAM BIT(18) 223 #define INACTIV_TMRS_EXST BIT(19) 224 #define NUM_INACTIV_TMRS BIT(20) 225 #define DESC_CACHE_DEPTH_SHIFT 21 226 #define DESC_CACHE_DEPTH_1 (0 << DESC_CACHE_DEPTH_SHIFT) 227 #define DESC_CACHE_DEPTH_2 (1 << DESC_CACHE_DEPTH_SHIFT) 228 #define DESC_CACHE_DEPTH_3 (2 << DESC_CACHE_DEPTH_SHIFT) 229 #define DESC_CACHE_DEPTH_4 (3 << DESC_CACHE_DEPTH_SHIFT) 230 #define CMD_DESC_EN BIT(23) 231 #define INACTIV_TMR_BASE_SHIFT 24 232 #define INACTIV_TMR_BASE_MASK 0xFF 233 234 /* BAM NUM PIPES */ 235 #define BAM_NUM_PIPES_SHIFT 0 236 #define BAM_NUM_PIPES_MASK 0xFF 237 #define PERIPH_NON_PIPE_GRP_SHIFT 16 238 #define PERIPH_NON_PIP_GRP_MASK 0xFF 239 #define BAM_NON_PIPE_GRP_SHIFT 24 240 #define BAM_NON_PIPE_GRP_MASK 0xFF 241 242 /* BAM CNFG BITS */ 243 #define BAM_PIPE_CNFG BIT(2) 244 #define BAM_FULL_PIPE BIT(11) 245 #define BAM_NO_EXT_P_RST BIT(12) 246 #define BAM_IBC_DISABLE BIT(13) 247 #define BAM_SB_CLK_REQ BIT(14) 248 #define BAM_PSM_CSW_REQ BIT(15) 249 #define BAM_PSM_P_RES BIT(16) 250 #define BAM_AU_P_RES BIT(17) 251 #define BAM_SI_P_RES BIT(18) 252 #define BAM_WB_P_RES BIT(19) 253 #define BAM_WB_BLK_CSW BIT(20) 254 #define BAM_WB_CSW_ACK_IDL BIT(21) 255 #define BAM_WB_RETR_SVPNT BIT(22) 256 #define BAM_WB_DSC_AVL_P_RST BIT(23) 257 #define BAM_REG_P_EN BIT(24) 258 #define BAM_PSM_P_HD_DATA BIT(25) 259 #define BAM_AU_ACCUMED BIT(26) 260 #define BAM_CMD_ENABLE BIT(27) 261 262 #define BAM_CNFG_BITS_DEFAULT (BAM_PIPE_CNFG | \ 263 BAM_NO_EXT_P_RST | \ 264 BAM_IBC_DISABLE | \ 265 BAM_SB_CLK_REQ | \ 266 BAM_PSM_CSW_REQ | \ 267 BAM_PSM_P_RES | \ 268 BAM_AU_P_RES | \ 269 BAM_SI_P_RES | \ 270 BAM_WB_P_RES | \ 271 BAM_WB_BLK_CSW | \ 272 BAM_WB_CSW_ACK_IDL | \ 273 BAM_WB_RETR_SVPNT | \ 274 BAM_WB_DSC_AVL_P_RST | \ 275 BAM_REG_P_EN | \ 276 BAM_PSM_P_HD_DATA | \ 277 BAM_AU_ACCUMED | \ 278 BAM_CMD_ENABLE) 279 280 /* PIPE CTRL */ 281 #define P_EN BIT(1) 282 #define P_DIRECTION BIT(3) 283 #define P_SYS_STRM BIT(4) 284 #define P_SYS_MODE BIT(5) 285 #define P_AUTO_EOB BIT(6) 286 #define P_AUTO_EOB_SEL_SHIFT 7 287 #define P_AUTO_EOB_SEL_512 (0 << P_AUTO_EOB_SEL_SHIFT) 288 #define P_AUTO_EOB_SEL_256 (1 << P_AUTO_EOB_SEL_SHIFT) 289 #define P_AUTO_EOB_SEL_128 (2 << P_AUTO_EOB_SEL_SHIFT) 290 #define P_AUTO_EOB_SEL_64 (3 << P_AUTO_EOB_SEL_SHIFT) 291 #define P_PREFETCH_LIMIT_SHIFT 9 292 #define P_PREFETCH_LIMIT_32 (0 << P_PREFETCH_LIMIT_SHIFT) 293 #define P_PREFETCH_LIMIT_16 (1 << P_PREFETCH_LIMIT_SHIFT) 294 #define P_PREFETCH_LIMIT_4 (2 << P_PREFETCH_LIMIT_SHIFT) 295 #define P_WRITE_NWD BIT(11) 296 #define P_LOCK_GROUP_SHIFT 16 297 #define P_LOCK_GROUP_MASK 0x1F 298 299 /* BAM_DESC_CNT_TRSHLD */ 300 #define CNT_TRSHLD 0xffff 301 #define DEFAULT_CNT_THRSHLD 0x4 302 303 /* BAM_IRQ_SRCS */ 304 #define BAM_IRQ BIT(31) 305 #define P_IRQ 0x7fffffff 306 307 /* BAM_IRQ_SRCS_MSK */ 308 #define BAM_IRQ_MSK BAM_IRQ 309 #define P_IRQ_MSK P_IRQ 310 311 /* BAM_IRQ_STTS */ 312 #define BAM_TIMER_IRQ BIT(4) 313 #define BAM_EMPTY_IRQ BIT(3) 314 #define BAM_ERROR_IRQ BIT(2) 315 #define BAM_HRESP_ERR_IRQ BIT(1) 316 317 /* BAM_IRQ_CLR */ 318 #define BAM_TIMER_CLR BIT(4) 319 #define BAM_EMPTY_CLR BIT(3) 320 #define BAM_ERROR_CLR BIT(2) 321 #define BAM_HRESP_ERR_CLR BIT(1) 322 323 /* BAM_IRQ_EN */ 324 #define BAM_TIMER_EN BIT(4) 325 #define BAM_EMPTY_EN BIT(3) 326 #define BAM_ERROR_EN BIT(2) 327 #define BAM_HRESP_ERR_EN BIT(1) 328 329 /* BAM_P_IRQ_EN */ 330 #define P_PRCSD_DESC_EN BIT(0) 331 #define P_TIMER_EN BIT(1) 332 #define P_WAKE_EN BIT(2) 333 #define P_OUT_OF_DESC_EN BIT(3) 334 #define P_ERR_EN BIT(4) 335 #define P_TRNSFR_END_EN BIT(5) 336 #define P_DEFAULT_IRQS_EN (P_PRCSD_DESC_EN | P_ERR_EN | P_TRNSFR_END_EN) 337 338 /* BAM_P_SW_OFSTS */ 339 #define P_SW_OFSTS_MASK 0xffff 340 341 #define BAM_DESC_FIFO_SIZE SZ_32K 342 #define MAX_DESCRIPTORS (BAM_DESC_FIFO_SIZE / sizeof(struct bam_desc_hw) - 1) 343 #define BAM_FIFO_SIZE (SZ_32K - 8) 344 #define IS_BUSY(chan) (CIRC_SPACE(bchan->tail, bchan->head,\ 345 MAX_DESCRIPTORS + 1) == 0) 346 347 struct bam_chan { 348 struct virt_dma_chan vc; 349 350 struct bam_device *bdev; 351 352 /* configuration from device tree */ 353 u32 id; 354 355 /* runtime configuration */ 356 struct dma_slave_config slave; 357 358 /* fifo storage */ 359 struct bam_desc_hw *fifo_virt; 360 dma_addr_t fifo_phys; 361 362 /* fifo markers */ 363 unsigned short head; /* start of active descriptor entries */ 364 unsigned short tail; /* end of active descriptor entries */ 365 366 unsigned int initialized; /* is the channel hw initialized? */ 367 unsigned int paused; /* is the channel paused? */ 368 unsigned int reconfigure; /* new slave config? */ 369 /* list of descriptors currently processed */ 370 struct list_head desc_list; 371 372 struct list_head node; 373 }; 374 375 static inline struct bam_chan *to_bam_chan(struct dma_chan *common) 376 { 377 return container_of(common, struct bam_chan, vc.chan); 378 } 379 380 struct bam_device { 381 void __iomem *regs; 382 struct device *dev; 383 struct dma_device common; 384 struct bam_chan *channels; 385 u32 num_channels; 386 u32 num_ees; 387 388 /* execution environment ID, from DT */ 389 u32 ee; 390 bool controlled_remotely; 391 bool powered_remotely; 392 u32 active_channels; 393 394 const struct reg_offset_data *layout; 395 396 struct clk *bamclk; 397 int irq; 398 399 /* dma start transaction tasklet */ 400 struct tasklet_struct task; 401 }; 402 403 /** 404 * bam_addr - returns BAM register address 405 * @bdev: bam device 406 * @pipe: pipe instance (ignored when register doesn't have multiple instances) 407 * @reg: register enum 408 */ 409 static inline void __iomem *bam_addr(struct bam_device *bdev, u32 pipe, 410 enum bam_reg reg) 411 { 412 const struct reg_offset_data r = bdev->layout[reg]; 413 414 return bdev->regs + r.base_offset + 415 r.pipe_mult * pipe + 416 r.evnt_mult * pipe + 417 r.ee_mult * bdev->ee; 418 } 419 420 /** 421 * bam_reset() - reset and initialize BAM registers 422 * @bdev: bam device 423 */ 424 static void bam_reset(struct bam_device *bdev) 425 { 426 u32 val; 427 428 /* s/w reset bam */ 429 /* after reset all pipes are disabled and idle */ 430 val = readl_relaxed(bam_addr(bdev, 0, BAM_CTRL)); 431 val |= BAM_SW_RST; 432 writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL)); 433 val &= ~BAM_SW_RST; 434 writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL)); 435 436 /* make sure previous stores are visible before enabling BAM */ 437 wmb(); 438 439 /* enable bam */ 440 val |= BAM_EN; 441 writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL)); 442 443 /* set descriptor threshold, start with 4 bytes */ 444 writel_relaxed(DEFAULT_CNT_THRSHLD, 445 bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); 446 447 /* Enable default set of h/w workarounds, ie all except BAM_FULL_PIPE */ 448 writel_relaxed(BAM_CNFG_BITS_DEFAULT, bam_addr(bdev, 0, BAM_CNFG_BITS)); 449 450 /* enable irqs for errors */ 451 writel_relaxed(BAM_ERROR_EN | BAM_HRESP_ERR_EN, 452 bam_addr(bdev, 0, BAM_IRQ_EN)); 453 454 /* unmask global bam interrupt */ 455 writel_relaxed(BAM_IRQ_MSK, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE)); 456 } 457 458 /** 459 * bam_reset_channel - Reset individual BAM DMA channel 460 * @bchan: bam channel 461 * 462 * This function resets a specific BAM channel 463 */ 464 static void bam_reset_channel(struct bam_chan *bchan) 465 { 466 struct bam_device *bdev = bchan->bdev; 467 468 lockdep_assert_held(&bchan->vc.lock); 469 470 /* reset channel */ 471 writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_RST)); 472 writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_RST)); 473 474 /* don't allow cpu to reorder BAM register accesses done after this */ 475 wmb(); 476 477 /* make sure hw is initialized when channel is used the first time */ 478 bchan->initialized = 0; 479 } 480 481 /** 482 * bam_chan_init_hw - Initialize channel hardware 483 * @bchan: bam channel 484 * @dir: DMA transfer direction 485 * 486 * This function resets and initializes the BAM channel 487 */ 488 static void bam_chan_init_hw(struct bam_chan *bchan, 489 enum dma_transfer_direction dir) 490 { 491 struct bam_device *bdev = bchan->bdev; 492 u32 val; 493 494 /* Reset the channel to clear internal state of the FIFO */ 495 bam_reset_channel(bchan); 496 497 /* 498 * write out 8 byte aligned address. We have enough space for this 499 * because we allocated 1 more descriptor (8 bytes) than we can use 500 */ 501 writel_relaxed(ALIGN(bchan->fifo_phys, sizeof(struct bam_desc_hw)), 502 bam_addr(bdev, bchan->id, BAM_P_DESC_FIFO_ADDR)); 503 writel_relaxed(BAM_FIFO_SIZE, 504 bam_addr(bdev, bchan->id, BAM_P_FIFO_SIZES)); 505 506 /* enable the per pipe interrupts, enable EOT, ERR, and INT irqs */ 507 writel_relaxed(P_DEFAULT_IRQS_EN, 508 bam_addr(bdev, bchan->id, BAM_P_IRQ_EN)); 509 510 /* unmask the specific pipe and EE combo */ 511 val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE)); 512 val |= BIT(bchan->id); 513 writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE)); 514 515 /* don't allow cpu to reorder the channel enable done below */ 516 wmb(); 517 518 /* set fixed direction and mode, then enable channel */ 519 val = P_EN | P_SYS_MODE; 520 if (dir == DMA_DEV_TO_MEM) 521 val |= P_DIRECTION; 522 523 writel_relaxed(val, bam_addr(bdev, bchan->id, BAM_P_CTRL)); 524 525 bchan->initialized = 1; 526 527 /* init FIFO pointers */ 528 bchan->head = 0; 529 bchan->tail = 0; 530 } 531 532 /** 533 * bam_alloc_chan - Allocate channel resources for DMA channel. 534 * @chan: specified channel 535 * 536 * This function allocates the FIFO descriptor memory 537 */ 538 static int bam_alloc_chan(struct dma_chan *chan) 539 { 540 struct bam_chan *bchan = to_bam_chan(chan); 541 struct bam_device *bdev = bchan->bdev; 542 543 if (bchan->fifo_virt) 544 return 0; 545 546 /* allocate FIFO descriptor space, but only if necessary */ 547 bchan->fifo_virt = dma_alloc_wc(bdev->dev, BAM_DESC_FIFO_SIZE, 548 &bchan->fifo_phys, GFP_KERNEL); 549 550 if (!bchan->fifo_virt) { 551 dev_err(bdev->dev, "Failed to allocate desc fifo\n"); 552 return -ENOMEM; 553 } 554 555 if (bdev->active_channels++ == 0 && bdev->powered_remotely) 556 bam_reset(bdev); 557 558 return 0; 559 } 560 561 /** 562 * bam_free_chan - Frees dma resources associated with specific channel 563 * @chan: specified channel 564 * 565 * Free the allocated fifo descriptor memory and channel resources 566 * 567 */ 568 static void bam_free_chan(struct dma_chan *chan) 569 { 570 struct bam_chan *bchan = to_bam_chan(chan); 571 struct bam_device *bdev = bchan->bdev; 572 u32 val; 573 unsigned long flags; 574 int ret; 575 576 ret = pm_runtime_get_sync(bdev->dev); 577 if (ret < 0) 578 return; 579 580 vchan_free_chan_resources(to_virt_chan(chan)); 581 582 if (!list_empty(&bchan->desc_list)) { 583 dev_err(bchan->bdev->dev, "Cannot free busy channel\n"); 584 goto err; 585 } 586 587 spin_lock_irqsave(&bchan->vc.lock, flags); 588 bam_reset_channel(bchan); 589 spin_unlock_irqrestore(&bchan->vc.lock, flags); 590 591 dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE, bchan->fifo_virt, 592 bchan->fifo_phys); 593 bchan->fifo_virt = NULL; 594 595 /* mask irq for pipe/channel */ 596 val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE)); 597 val &= ~BIT(bchan->id); 598 writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE)); 599 600 /* disable irq */ 601 writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_IRQ_EN)); 602 603 if (--bdev->active_channels == 0 && bdev->powered_remotely) { 604 /* s/w reset bam */ 605 val = readl_relaxed(bam_addr(bdev, 0, BAM_CTRL)); 606 val |= BAM_SW_RST; 607 writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL)); 608 } 609 610 err: 611 pm_runtime_mark_last_busy(bdev->dev); 612 pm_runtime_put_autosuspend(bdev->dev); 613 } 614 615 /** 616 * bam_slave_config - set slave configuration for channel 617 * @chan: dma channel 618 * @cfg: slave configuration 619 * 620 * Sets slave configuration for channel 621 * 622 */ 623 static int bam_slave_config(struct dma_chan *chan, 624 struct dma_slave_config *cfg) 625 { 626 struct bam_chan *bchan = to_bam_chan(chan); 627 unsigned long flag; 628 629 spin_lock_irqsave(&bchan->vc.lock, flag); 630 memcpy(&bchan->slave, cfg, sizeof(*cfg)); 631 bchan->reconfigure = 1; 632 spin_unlock_irqrestore(&bchan->vc.lock, flag); 633 634 return 0; 635 } 636 637 /** 638 * bam_prep_slave_sg - Prep slave sg transaction 639 * 640 * @chan: dma channel 641 * @sgl: scatter gather list 642 * @sg_len: length of sg 643 * @direction: DMA transfer direction 644 * @flags: DMA flags 645 * @context: transfer context (unused) 646 */ 647 static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan, 648 struct scatterlist *sgl, unsigned int sg_len, 649 enum dma_transfer_direction direction, unsigned long flags, 650 void *context) 651 { 652 struct bam_chan *bchan = to_bam_chan(chan); 653 struct bam_device *bdev = bchan->bdev; 654 struct bam_async_desc *async_desc; 655 struct scatterlist *sg; 656 u32 i; 657 struct bam_desc_hw *desc; 658 unsigned int num_alloc = 0; 659 660 661 if (!is_slave_direction(direction)) { 662 dev_err(bdev->dev, "invalid dma direction\n"); 663 return NULL; 664 } 665 666 /* calculate number of required entries */ 667 for_each_sg(sgl, sg, sg_len, i) 668 num_alloc += DIV_ROUND_UP(sg_dma_len(sg), BAM_FIFO_SIZE); 669 670 /* allocate enough room to accommodate the number of entries */ 671 async_desc = kzalloc(struct_size(async_desc, desc, num_alloc), 672 GFP_NOWAIT); 673 674 if (!async_desc) 675 return NULL; 676 677 if (flags & DMA_PREP_FENCE) 678 async_desc->flags |= DESC_FLAG_NWD; 679 680 if (flags & DMA_PREP_INTERRUPT) 681 async_desc->flags |= DESC_FLAG_EOT; 682 683 async_desc->num_desc = num_alloc; 684 async_desc->curr_desc = async_desc->desc; 685 async_desc->dir = direction; 686 687 /* fill in temporary descriptors */ 688 desc = async_desc->desc; 689 for_each_sg(sgl, sg, sg_len, i) { 690 unsigned int remainder = sg_dma_len(sg); 691 unsigned int curr_offset = 0; 692 693 do { 694 if (flags & DMA_PREP_CMD) 695 desc->flags |= cpu_to_le16(DESC_FLAG_CMD); 696 697 desc->addr = cpu_to_le32(sg_dma_address(sg) + 698 curr_offset); 699 700 if (remainder > BAM_FIFO_SIZE) { 701 desc->size = cpu_to_le16(BAM_FIFO_SIZE); 702 remainder -= BAM_FIFO_SIZE; 703 curr_offset += BAM_FIFO_SIZE; 704 } else { 705 desc->size = cpu_to_le16(remainder); 706 remainder = 0; 707 } 708 709 async_desc->length += le16_to_cpu(desc->size); 710 desc++; 711 } while (remainder > 0); 712 } 713 714 return vchan_tx_prep(&bchan->vc, &async_desc->vd, flags); 715 } 716 717 /** 718 * bam_dma_terminate_all - terminate all transactions on a channel 719 * @chan: bam dma channel 720 * 721 * Dequeues and frees all transactions 722 * No callbacks are done 723 * 724 */ 725 static int bam_dma_terminate_all(struct dma_chan *chan) 726 { 727 struct bam_chan *bchan = to_bam_chan(chan); 728 struct bam_async_desc *async_desc, *tmp; 729 unsigned long flag; 730 LIST_HEAD(head); 731 732 /* remove all transactions, including active transaction */ 733 spin_lock_irqsave(&bchan->vc.lock, flag); 734 /* 735 * If we have transactions queued, then some might be committed to the 736 * hardware in the desc fifo. The only way to reset the desc fifo is 737 * to do a hardware reset (either by pipe or the entire block). 738 * bam_chan_init_hw() will trigger a pipe reset, and also reinit the 739 * pipe. If the pipe is left disabled (default state after pipe reset) 740 * and is accessed by a connected hardware engine, a fatal error in 741 * the BAM will occur. There is a small window where this could happen 742 * with bam_chan_init_hw(), but it is assumed that the caller has 743 * stopped activity on any attached hardware engine. Make sure to do 744 * this first so that the BAM hardware doesn't cause memory corruption 745 * by accessing freed resources. 746 */ 747 if (!list_empty(&bchan->desc_list)) { 748 async_desc = list_first_entry(&bchan->desc_list, 749 struct bam_async_desc, desc_node); 750 bam_chan_init_hw(bchan, async_desc->dir); 751 } 752 753 list_for_each_entry_safe(async_desc, tmp, 754 &bchan->desc_list, desc_node) { 755 list_add(&async_desc->vd.node, &bchan->vc.desc_issued); 756 list_del(&async_desc->desc_node); 757 } 758 759 vchan_get_all_descriptors(&bchan->vc, &head); 760 spin_unlock_irqrestore(&bchan->vc.lock, flag); 761 762 vchan_dma_desc_free_list(&bchan->vc, &head); 763 764 return 0; 765 } 766 767 /** 768 * bam_pause - Pause DMA channel 769 * @chan: dma channel 770 * 771 */ 772 static int bam_pause(struct dma_chan *chan) 773 { 774 struct bam_chan *bchan = to_bam_chan(chan); 775 struct bam_device *bdev = bchan->bdev; 776 unsigned long flag; 777 int ret; 778 779 ret = pm_runtime_get_sync(bdev->dev); 780 if (ret < 0) 781 return ret; 782 783 spin_lock_irqsave(&bchan->vc.lock, flag); 784 writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_HALT)); 785 bchan->paused = 1; 786 spin_unlock_irqrestore(&bchan->vc.lock, flag); 787 pm_runtime_mark_last_busy(bdev->dev); 788 pm_runtime_put_autosuspend(bdev->dev); 789 790 return 0; 791 } 792 793 /** 794 * bam_resume - Resume DMA channel operations 795 * @chan: dma channel 796 * 797 */ 798 static int bam_resume(struct dma_chan *chan) 799 { 800 struct bam_chan *bchan = to_bam_chan(chan); 801 struct bam_device *bdev = bchan->bdev; 802 unsigned long flag; 803 int ret; 804 805 ret = pm_runtime_get_sync(bdev->dev); 806 if (ret < 0) 807 return ret; 808 809 spin_lock_irqsave(&bchan->vc.lock, flag); 810 writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_HALT)); 811 bchan->paused = 0; 812 spin_unlock_irqrestore(&bchan->vc.lock, flag); 813 pm_runtime_mark_last_busy(bdev->dev); 814 pm_runtime_put_autosuspend(bdev->dev); 815 816 return 0; 817 } 818 819 /** 820 * process_channel_irqs - processes the channel interrupts 821 * @bdev: bam controller 822 * 823 * This function processes the channel interrupts 824 * 825 */ 826 static u32 process_channel_irqs(struct bam_device *bdev) 827 { 828 u32 i, srcs, pipe_stts, offset, avail; 829 unsigned long flags; 830 struct bam_async_desc *async_desc, *tmp; 831 832 srcs = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_EE)); 833 834 /* return early if no pipe/channel interrupts are present */ 835 if (!(srcs & P_IRQ)) 836 return srcs; 837 838 for (i = 0; i < bdev->num_channels; i++) { 839 struct bam_chan *bchan = &bdev->channels[i]; 840 841 if (!(srcs & BIT(i))) 842 continue; 843 844 /* clear pipe irq */ 845 pipe_stts = readl_relaxed(bam_addr(bdev, i, BAM_P_IRQ_STTS)); 846 847 writel_relaxed(pipe_stts, bam_addr(bdev, i, BAM_P_IRQ_CLR)); 848 849 spin_lock_irqsave(&bchan->vc.lock, flags); 850 851 offset = readl_relaxed(bam_addr(bdev, i, BAM_P_SW_OFSTS)) & 852 P_SW_OFSTS_MASK; 853 offset /= sizeof(struct bam_desc_hw); 854 855 /* Number of bytes available to read */ 856 avail = CIRC_CNT(offset, bchan->head, MAX_DESCRIPTORS + 1); 857 858 if (offset < bchan->head) 859 avail--; 860 861 list_for_each_entry_safe(async_desc, tmp, 862 &bchan->desc_list, desc_node) { 863 /* Not enough data to read */ 864 if (avail < async_desc->xfer_len) 865 break; 866 867 /* manage FIFO */ 868 bchan->head += async_desc->xfer_len; 869 bchan->head %= MAX_DESCRIPTORS; 870 871 async_desc->num_desc -= async_desc->xfer_len; 872 async_desc->curr_desc += async_desc->xfer_len; 873 avail -= async_desc->xfer_len; 874 875 /* 876 * if complete, process cookie. Otherwise 877 * push back to front of desc_issued so that 878 * it gets restarted by the tasklet 879 */ 880 if (!async_desc->num_desc) { 881 vchan_cookie_complete(&async_desc->vd); 882 } else { 883 list_add(&async_desc->vd.node, 884 &bchan->vc.desc_issued); 885 } 886 list_del(&async_desc->desc_node); 887 } 888 889 spin_unlock_irqrestore(&bchan->vc.lock, flags); 890 } 891 892 return srcs; 893 } 894 895 /** 896 * bam_dma_irq - irq handler for bam controller 897 * @irq: IRQ of interrupt 898 * @data: callback data 899 * 900 * IRQ handler for the bam controller 901 */ 902 static irqreturn_t bam_dma_irq(int irq, void *data) 903 { 904 struct bam_device *bdev = data; 905 u32 clr_mask = 0, srcs = 0; 906 int ret; 907 908 srcs |= process_channel_irqs(bdev); 909 910 /* kick off tasklet to start next dma transfer */ 911 if (srcs & P_IRQ) 912 tasklet_schedule(&bdev->task); 913 914 ret = pm_runtime_get_sync(bdev->dev); 915 if (ret < 0) 916 return IRQ_NONE; 917 918 if (srcs & BAM_IRQ) { 919 clr_mask = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_STTS)); 920 921 /* 922 * don't allow reorder of the various accesses to the BAM 923 * registers 924 */ 925 mb(); 926 927 writel_relaxed(clr_mask, bam_addr(bdev, 0, BAM_IRQ_CLR)); 928 } 929 930 pm_runtime_mark_last_busy(bdev->dev); 931 pm_runtime_put_autosuspend(bdev->dev); 932 933 return IRQ_HANDLED; 934 } 935 936 /** 937 * bam_tx_status - returns status of transaction 938 * @chan: dma channel 939 * @cookie: transaction cookie 940 * @txstate: DMA transaction state 941 * 942 * Return status of dma transaction 943 */ 944 static enum dma_status bam_tx_status(struct dma_chan *chan, dma_cookie_t cookie, 945 struct dma_tx_state *txstate) 946 { 947 struct bam_chan *bchan = to_bam_chan(chan); 948 struct bam_async_desc *async_desc; 949 struct virt_dma_desc *vd; 950 int ret; 951 size_t residue = 0; 952 unsigned int i; 953 unsigned long flags; 954 955 ret = dma_cookie_status(chan, cookie, txstate); 956 if (ret == DMA_COMPLETE) 957 return ret; 958 959 if (!txstate) 960 return bchan->paused ? DMA_PAUSED : ret; 961 962 spin_lock_irqsave(&bchan->vc.lock, flags); 963 vd = vchan_find_desc(&bchan->vc, cookie); 964 if (vd) { 965 residue = container_of(vd, struct bam_async_desc, vd)->length; 966 } else { 967 list_for_each_entry(async_desc, &bchan->desc_list, desc_node) { 968 if (async_desc->vd.tx.cookie != cookie) 969 continue; 970 971 for (i = 0; i < async_desc->num_desc; i++) 972 residue += le16_to_cpu( 973 async_desc->curr_desc[i].size); 974 } 975 } 976 977 spin_unlock_irqrestore(&bchan->vc.lock, flags); 978 979 dma_set_residue(txstate, residue); 980 981 if (ret == DMA_IN_PROGRESS && bchan->paused) 982 ret = DMA_PAUSED; 983 984 return ret; 985 } 986 987 /** 988 * bam_apply_new_config 989 * @bchan: bam dma channel 990 * @dir: DMA direction 991 */ 992 static void bam_apply_new_config(struct bam_chan *bchan, 993 enum dma_transfer_direction dir) 994 { 995 struct bam_device *bdev = bchan->bdev; 996 u32 maxburst; 997 998 if (!bdev->controlled_remotely) { 999 if (dir == DMA_DEV_TO_MEM) 1000 maxburst = bchan->slave.src_maxburst; 1001 else 1002 maxburst = bchan->slave.dst_maxburst; 1003 1004 writel_relaxed(maxburst, 1005 bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); 1006 } 1007 1008 bchan->reconfigure = 0; 1009 } 1010 1011 /** 1012 * bam_start_dma - start next transaction 1013 * @bchan: bam dma channel 1014 */ 1015 static void bam_start_dma(struct bam_chan *bchan) 1016 { 1017 struct virt_dma_desc *vd = vchan_next_desc(&bchan->vc); 1018 struct bam_device *bdev = bchan->bdev; 1019 struct bam_async_desc *async_desc = NULL; 1020 struct bam_desc_hw *desc; 1021 struct bam_desc_hw *fifo = PTR_ALIGN(bchan->fifo_virt, 1022 sizeof(struct bam_desc_hw)); 1023 int ret; 1024 unsigned int avail; 1025 struct dmaengine_desc_callback cb; 1026 1027 lockdep_assert_held(&bchan->vc.lock); 1028 1029 if (!vd) 1030 return; 1031 1032 ret = pm_runtime_get_sync(bdev->dev); 1033 if (ret < 0) 1034 return; 1035 1036 while (vd && !IS_BUSY(bchan)) { 1037 list_del(&vd->node); 1038 1039 async_desc = container_of(vd, struct bam_async_desc, vd); 1040 1041 /* on first use, initialize the channel hardware */ 1042 if (!bchan->initialized) 1043 bam_chan_init_hw(bchan, async_desc->dir); 1044 1045 /* apply new slave config changes, if necessary */ 1046 if (bchan->reconfigure) 1047 bam_apply_new_config(bchan, async_desc->dir); 1048 1049 desc = async_desc->curr_desc; 1050 avail = CIRC_SPACE(bchan->tail, bchan->head, 1051 MAX_DESCRIPTORS + 1); 1052 1053 if (async_desc->num_desc > avail) 1054 async_desc->xfer_len = avail; 1055 else 1056 async_desc->xfer_len = async_desc->num_desc; 1057 1058 /* set any special flags on the last descriptor */ 1059 if (async_desc->num_desc == async_desc->xfer_len) 1060 desc[async_desc->xfer_len - 1].flags |= 1061 cpu_to_le16(async_desc->flags); 1062 1063 vd = vchan_next_desc(&bchan->vc); 1064 1065 dmaengine_desc_get_callback(&async_desc->vd.tx, &cb); 1066 1067 /* 1068 * An interrupt is generated at this desc, if 1069 * - FIFO is FULL. 1070 * - No more descriptors to add. 1071 * - If a callback completion was requested for this DESC, 1072 * In this case, BAM will deliver the completion callback 1073 * for this desc and continue processing the next desc. 1074 */ 1075 if (((avail <= async_desc->xfer_len) || !vd || 1076 dmaengine_desc_callback_valid(&cb)) && 1077 !(async_desc->flags & DESC_FLAG_EOT)) 1078 desc[async_desc->xfer_len - 1].flags |= 1079 cpu_to_le16(DESC_FLAG_INT); 1080 1081 if (bchan->tail + async_desc->xfer_len > MAX_DESCRIPTORS) { 1082 u32 partial = MAX_DESCRIPTORS - bchan->tail; 1083 1084 memcpy(&fifo[bchan->tail], desc, 1085 partial * sizeof(struct bam_desc_hw)); 1086 memcpy(fifo, &desc[partial], 1087 (async_desc->xfer_len - partial) * 1088 sizeof(struct bam_desc_hw)); 1089 } else { 1090 memcpy(&fifo[bchan->tail], desc, 1091 async_desc->xfer_len * 1092 sizeof(struct bam_desc_hw)); 1093 } 1094 1095 bchan->tail += async_desc->xfer_len; 1096 bchan->tail %= MAX_DESCRIPTORS; 1097 list_add_tail(&async_desc->desc_node, &bchan->desc_list); 1098 } 1099 1100 /* ensure descriptor writes and dma start not reordered */ 1101 wmb(); 1102 writel_relaxed(bchan->tail * sizeof(struct bam_desc_hw), 1103 bam_addr(bdev, bchan->id, BAM_P_EVNT_REG)); 1104 1105 pm_runtime_mark_last_busy(bdev->dev); 1106 pm_runtime_put_autosuspend(bdev->dev); 1107 } 1108 1109 /** 1110 * dma_tasklet - DMA IRQ tasklet 1111 * @t: tasklet argument (bam controller structure) 1112 * 1113 * Sets up next DMA operation and then processes all completed transactions 1114 */ 1115 static void dma_tasklet(struct tasklet_struct *t) 1116 { 1117 struct bam_device *bdev = from_tasklet(bdev, t, task); 1118 struct bam_chan *bchan; 1119 unsigned long flags; 1120 unsigned int i; 1121 1122 /* go through the channels and kick off transactions */ 1123 for (i = 0; i < bdev->num_channels; i++) { 1124 bchan = &bdev->channels[i]; 1125 spin_lock_irqsave(&bchan->vc.lock, flags); 1126 1127 if (!list_empty(&bchan->vc.desc_issued) && !IS_BUSY(bchan)) 1128 bam_start_dma(bchan); 1129 spin_unlock_irqrestore(&bchan->vc.lock, flags); 1130 } 1131 1132 } 1133 1134 /** 1135 * bam_issue_pending - starts pending transactions 1136 * @chan: dma channel 1137 * 1138 * Calls tasklet directly which in turn starts any pending transactions 1139 */ 1140 static void bam_issue_pending(struct dma_chan *chan) 1141 { 1142 struct bam_chan *bchan = to_bam_chan(chan); 1143 unsigned long flags; 1144 1145 spin_lock_irqsave(&bchan->vc.lock, flags); 1146 1147 /* if work pending and idle, start a transaction */ 1148 if (vchan_issue_pending(&bchan->vc) && !IS_BUSY(bchan)) 1149 bam_start_dma(bchan); 1150 1151 spin_unlock_irqrestore(&bchan->vc.lock, flags); 1152 } 1153 1154 /** 1155 * bam_dma_free_desc - free descriptor memory 1156 * @vd: virtual descriptor 1157 * 1158 */ 1159 static void bam_dma_free_desc(struct virt_dma_desc *vd) 1160 { 1161 struct bam_async_desc *async_desc = container_of(vd, 1162 struct bam_async_desc, vd); 1163 1164 kfree(async_desc); 1165 } 1166 1167 static struct dma_chan *bam_dma_xlate(struct of_phandle_args *dma_spec, 1168 struct of_dma *of) 1169 { 1170 struct bam_device *bdev = container_of(of->of_dma_data, 1171 struct bam_device, common); 1172 unsigned int request; 1173 1174 if (dma_spec->args_count != 1) 1175 return NULL; 1176 1177 request = dma_spec->args[0]; 1178 if (request >= bdev->num_channels) 1179 return NULL; 1180 1181 return dma_get_slave_channel(&(bdev->channels[request].vc.chan)); 1182 } 1183 1184 /** 1185 * bam_init 1186 * @bdev: bam device 1187 * 1188 * Initialization helper for global bam registers 1189 */ 1190 static int bam_init(struct bam_device *bdev) 1191 { 1192 u32 val; 1193 1194 /* read revision and configuration information */ 1195 if (!bdev->num_ees) { 1196 val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION)); 1197 bdev->num_ees = (val >> NUM_EES_SHIFT) & NUM_EES_MASK; 1198 } 1199 1200 /* check that configured EE is within range */ 1201 if (bdev->ee >= bdev->num_ees) 1202 return -EINVAL; 1203 1204 if (!bdev->num_channels) { 1205 val = readl_relaxed(bam_addr(bdev, 0, BAM_NUM_PIPES)); 1206 bdev->num_channels = val & BAM_NUM_PIPES_MASK; 1207 } 1208 1209 /* Reset BAM now if fully controlled locally */ 1210 if (!bdev->controlled_remotely && !bdev->powered_remotely) 1211 bam_reset(bdev); 1212 1213 return 0; 1214 } 1215 1216 static void bam_channel_init(struct bam_device *bdev, struct bam_chan *bchan, 1217 u32 index) 1218 { 1219 bchan->id = index; 1220 bchan->bdev = bdev; 1221 1222 vchan_init(&bchan->vc, &bdev->common); 1223 bchan->vc.desc_free = bam_dma_free_desc; 1224 INIT_LIST_HEAD(&bchan->desc_list); 1225 } 1226 1227 static const struct of_device_id bam_of_match[] = { 1228 { .compatible = "qcom,bam-v1.3.0", .data = &bam_v1_3_reg_info }, 1229 { .compatible = "qcom,bam-v1.4.0", .data = &bam_v1_4_reg_info }, 1230 { .compatible = "qcom,bam-v1.7.0", .data = &bam_v1_7_reg_info }, 1231 {} 1232 }; 1233 1234 MODULE_DEVICE_TABLE(of, bam_of_match); 1235 1236 static int bam_dma_probe(struct platform_device *pdev) 1237 { 1238 struct bam_device *bdev; 1239 const struct of_device_id *match; 1240 int ret, i; 1241 1242 bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL); 1243 if (!bdev) 1244 return -ENOMEM; 1245 1246 bdev->dev = &pdev->dev; 1247 1248 match = of_match_node(bam_of_match, pdev->dev.of_node); 1249 if (!match) { 1250 dev_err(&pdev->dev, "Unsupported BAM module\n"); 1251 return -ENODEV; 1252 } 1253 1254 bdev->layout = match->data; 1255 1256 bdev->regs = devm_platform_ioremap_resource(pdev, 0); 1257 if (IS_ERR(bdev->regs)) 1258 return PTR_ERR(bdev->regs); 1259 1260 bdev->irq = platform_get_irq(pdev, 0); 1261 if (bdev->irq < 0) 1262 return bdev->irq; 1263 1264 ret = of_property_read_u32(pdev->dev.of_node, "qcom,ee", &bdev->ee); 1265 if (ret) { 1266 dev_err(bdev->dev, "Execution environment unspecified\n"); 1267 return ret; 1268 } 1269 1270 bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node, 1271 "qcom,controlled-remotely"); 1272 bdev->powered_remotely = of_property_read_bool(pdev->dev.of_node, 1273 "qcom,powered-remotely"); 1274 1275 if (bdev->controlled_remotely || bdev->powered_remotely) 1276 bdev->bamclk = devm_clk_get_optional(bdev->dev, "bam_clk"); 1277 else 1278 bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk"); 1279 1280 if (IS_ERR(bdev->bamclk)) 1281 return PTR_ERR(bdev->bamclk); 1282 1283 if (!bdev->bamclk) { 1284 ret = of_property_read_u32(pdev->dev.of_node, "num-channels", 1285 &bdev->num_channels); 1286 if (ret) 1287 dev_err(bdev->dev, "num-channels unspecified in dt\n"); 1288 1289 ret = of_property_read_u32(pdev->dev.of_node, "qcom,num-ees", 1290 &bdev->num_ees); 1291 if (ret) 1292 dev_err(bdev->dev, "num-ees unspecified in dt\n"); 1293 } 1294 1295 ret = clk_prepare_enable(bdev->bamclk); 1296 if (ret) { 1297 dev_err(bdev->dev, "failed to prepare/enable clock\n"); 1298 return ret; 1299 } 1300 1301 ret = bam_init(bdev); 1302 if (ret) 1303 goto err_disable_clk; 1304 1305 tasklet_setup(&bdev->task, dma_tasklet); 1306 1307 bdev->channels = devm_kcalloc(bdev->dev, bdev->num_channels, 1308 sizeof(*bdev->channels), GFP_KERNEL); 1309 1310 if (!bdev->channels) { 1311 ret = -ENOMEM; 1312 goto err_tasklet_kill; 1313 } 1314 1315 /* allocate and initialize channels */ 1316 INIT_LIST_HEAD(&bdev->common.channels); 1317 1318 for (i = 0; i < bdev->num_channels; i++) 1319 bam_channel_init(bdev, &bdev->channels[i], i); 1320 1321 ret = devm_request_irq(bdev->dev, bdev->irq, bam_dma_irq, 1322 IRQF_TRIGGER_HIGH, "bam_dma", bdev); 1323 if (ret) 1324 goto err_bam_channel_exit; 1325 1326 /* set max dma segment size */ 1327 bdev->common.dev = bdev->dev; 1328 dma_set_max_seg_size(bdev->common.dev, BAM_FIFO_SIZE); 1329 1330 platform_set_drvdata(pdev, bdev); 1331 1332 /* set capabilities */ 1333 dma_cap_zero(bdev->common.cap_mask); 1334 dma_cap_set(DMA_SLAVE, bdev->common.cap_mask); 1335 1336 /* initialize dmaengine apis */ 1337 bdev->common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); 1338 bdev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; 1339 bdev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES; 1340 bdev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES; 1341 bdev->common.device_alloc_chan_resources = bam_alloc_chan; 1342 bdev->common.device_free_chan_resources = bam_free_chan; 1343 bdev->common.device_prep_slave_sg = bam_prep_slave_sg; 1344 bdev->common.device_config = bam_slave_config; 1345 bdev->common.device_pause = bam_pause; 1346 bdev->common.device_resume = bam_resume; 1347 bdev->common.device_terminate_all = bam_dma_terminate_all; 1348 bdev->common.device_issue_pending = bam_issue_pending; 1349 bdev->common.device_tx_status = bam_tx_status; 1350 bdev->common.dev = bdev->dev; 1351 1352 ret = dma_async_device_register(&bdev->common); 1353 if (ret) { 1354 dev_err(bdev->dev, "failed to register dma async device\n"); 1355 goto err_bam_channel_exit; 1356 } 1357 1358 ret = of_dma_controller_register(pdev->dev.of_node, bam_dma_xlate, 1359 &bdev->common); 1360 if (ret) 1361 goto err_unregister_dma; 1362 1363 pm_runtime_irq_safe(&pdev->dev); 1364 pm_runtime_set_autosuspend_delay(&pdev->dev, BAM_DMA_AUTOSUSPEND_DELAY); 1365 pm_runtime_use_autosuspend(&pdev->dev); 1366 pm_runtime_mark_last_busy(&pdev->dev); 1367 pm_runtime_set_active(&pdev->dev); 1368 pm_runtime_enable(&pdev->dev); 1369 1370 return 0; 1371 1372 err_unregister_dma: 1373 dma_async_device_unregister(&bdev->common); 1374 err_bam_channel_exit: 1375 for (i = 0; i < bdev->num_channels; i++) 1376 tasklet_kill(&bdev->channels[i].vc.task); 1377 err_tasklet_kill: 1378 tasklet_kill(&bdev->task); 1379 err_disable_clk: 1380 clk_disable_unprepare(bdev->bamclk); 1381 1382 return ret; 1383 } 1384 1385 static void bam_dma_remove(struct platform_device *pdev) 1386 { 1387 struct bam_device *bdev = platform_get_drvdata(pdev); 1388 u32 i; 1389 1390 pm_runtime_force_suspend(&pdev->dev); 1391 1392 of_dma_controller_free(pdev->dev.of_node); 1393 dma_async_device_unregister(&bdev->common); 1394 1395 /* mask all interrupts for this execution environment */ 1396 writel_relaxed(0, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE)); 1397 1398 devm_free_irq(bdev->dev, bdev->irq, bdev); 1399 1400 for (i = 0; i < bdev->num_channels; i++) { 1401 bam_dma_terminate_all(&bdev->channels[i].vc.chan); 1402 tasklet_kill(&bdev->channels[i].vc.task); 1403 1404 if (!bdev->channels[i].fifo_virt) 1405 continue; 1406 1407 dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE, 1408 bdev->channels[i].fifo_virt, 1409 bdev->channels[i].fifo_phys); 1410 } 1411 1412 tasklet_kill(&bdev->task); 1413 1414 clk_disable_unprepare(bdev->bamclk); 1415 } 1416 1417 static int __maybe_unused bam_dma_runtime_suspend(struct device *dev) 1418 { 1419 struct bam_device *bdev = dev_get_drvdata(dev); 1420 1421 clk_disable(bdev->bamclk); 1422 1423 return 0; 1424 } 1425 1426 static int __maybe_unused bam_dma_runtime_resume(struct device *dev) 1427 { 1428 struct bam_device *bdev = dev_get_drvdata(dev); 1429 int ret; 1430 1431 ret = clk_enable(bdev->bamclk); 1432 if (ret < 0) { 1433 dev_err(dev, "clk_enable failed: %d\n", ret); 1434 return ret; 1435 } 1436 1437 return 0; 1438 } 1439 1440 static int __maybe_unused bam_dma_suspend(struct device *dev) 1441 { 1442 struct bam_device *bdev = dev_get_drvdata(dev); 1443 1444 pm_runtime_force_suspend(dev); 1445 clk_unprepare(bdev->bamclk); 1446 1447 return 0; 1448 } 1449 1450 static int __maybe_unused bam_dma_resume(struct device *dev) 1451 { 1452 struct bam_device *bdev = dev_get_drvdata(dev); 1453 int ret; 1454 1455 ret = clk_prepare(bdev->bamclk); 1456 if (ret) 1457 return ret; 1458 1459 pm_runtime_force_resume(dev); 1460 1461 return 0; 1462 } 1463 1464 static const struct dev_pm_ops bam_dma_pm_ops = { 1465 SET_LATE_SYSTEM_SLEEP_PM_OPS(bam_dma_suspend, bam_dma_resume) 1466 SET_RUNTIME_PM_OPS(bam_dma_runtime_suspend, bam_dma_runtime_resume, 1467 NULL) 1468 }; 1469 1470 static struct platform_driver bam_dma_driver = { 1471 .probe = bam_dma_probe, 1472 .remove_new = bam_dma_remove, 1473 .driver = { 1474 .name = "bam-dma-engine", 1475 .pm = &bam_dma_pm_ops, 1476 .of_match_table = bam_of_match, 1477 }, 1478 }; 1479 1480 module_platform_driver(bam_dma_driver); 1481 1482 MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>"); 1483 MODULE_DESCRIPTION("QCOM BAM DMA engine driver"); 1484 MODULE_LICENSE("GPL v2"); 1485