Rongjun Ying | ca21a14 | 2011-10-27 19:22:39 -0700 | [diff] [blame] | 1 | /* |
| 2 | * DMA controller driver for CSR SiRFprimaII |
| 3 | * |
| 4 | * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company. |
| 5 | * |
| 6 | * Licensed under GPLv2 or later. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/module.h> |
| 10 | #include <linux/dmaengine.h> |
| 11 | #include <linux/dma-mapping.h> |
| 12 | #include <linux/interrupt.h> |
| 13 | #include <linux/io.h> |
| 14 | #include <linux/slab.h> |
| 15 | #include <linux/of_irq.h> |
| 16 | #include <linux/of_address.h> |
| 17 | #include <linux/of_device.h> |
| 18 | #include <linux/of_platform.h> |
| 19 | #include <linux/sirfsoc_dma.h> |
| 20 | |
| 21 | #define SIRFSOC_DMA_DESCRIPTORS 16 |
| 22 | #define SIRFSOC_DMA_CHANNELS 16 |
| 23 | |
| 24 | #define SIRFSOC_DMA_CH_ADDR 0x00 |
| 25 | #define SIRFSOC_DMA_CH_XLEN 0x04 |
| 26 | #define SIRFSOC_DMA_CH_YLEN 0x08 |
| 27 | #define SIRFSOC_DMA_CH_CTRL 0x0C |
| 28 | |
| 29 | #define SIRFSOC_DMA_WIDTH_0 0x100 |
| 30 | #define SIRFSOC_DMA_CH_VALID 0x140 |
| 31 | #define SIRFSOC_DMA_CH_INT 0x144 |
| 32 | #define SIRFSOC_DMA_INT_EN 0x148 |
| 33 | #define SIRFSOC_DMA_CH_LOOP_CTRL 0x150 |
| 34 | |
| 35 | #define SIRFSOC_DMA_MODE_CTRL_BIT 4 |
| 36 | #define SIRFSOC_DMA_DIR_CTRL_BIT 5 |
| 37 | |
| 38 | /* xlen and dma_width register is in 4 bytes boundary */ |
| 39 | #define SIRFSOC_DMA_WORD_LEN 4 |
| 40 | |
| 41 | struct sirfsoc_dma_desc { |
| 42 | struct dma_async_tx_descriptor desc; |
| 43 | struct list_head node; |
| 44 | |
| 45 | /* SiRFprimaII 2D-DMA parameters */ |
| 46 | |
| 47 | int xlen; /* DMA xlen */ |
| 48 | int ylen; /* DMA ylen */ |
| 49 | int width; /* DMA width */ |
| 50 | int dir; |
| 51 | bool cyclic; /* is loop DMA? */ |
| 52 | u32 addr; /* DMA buffer address */ |
| 53 | }; |
| 54 | |
| 55 | struct sirfsoc_dma_chan { |
| 56 | struct dma_chan chan; |
| 57 | struct list_head free; |
| 58 | struct list_head prepared; |
| 59 | struct list_head queued; |
| 60 | struct list_head active; |
| 61 | struct list_head completed; |
| 62 | dma_cookie_t completed_cookie; |
| 63 | unsigned long happened_cyclic; |
| 64 | unsigned long completed_cyclic; |
| 65 | |
| 66 | /* Lock for this structure */ |
| 67 | spinlock_t lock; |
| 68 | |
| 69 | int mode; |
| 70 | }; |
| 71 | |
| 72 | struct sirfsoc_dma { |
| 73 | struct dma_device dma; |
| 74 | struct tasklet_struct tasklet; |
| 75 | struct sirfsoc_dma_chan channels[SIRFSOC_DMA_CHANNELS]; |
| 76 | void __iomem *base; |
| 77 | int irq; |
| 78 | }; |
| 79 | |
| 80 | #define DRV_NAME "sirfsoc_dma" |
| 81 | |
| 82 | /* Convert struct dma_chan to struct sirfsoc_dma_chan */ |
| 83 | static inline |
| 84 | struct sirfsoc_dma_chan *dma_chan_to_sirfsoc_dma_chan(struct dma_chan *c) |
| 85 | { |
| 86 | return container_of(c, struct sirfsoc_dma_chan, chan); |
| 87 | } |
| 88 | |
| 89 | /* Convert struct dma_chan to struct sirfsoc_dma */ |
| 90 | static inline struct sirfsoc_dma *dma_chan_to_sirfsoc_dma(struct dma_chan *c) |
| 91 | { |
| 92 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(c); |
| 93 | return container_of(schan, struct sirfsoc_dma, channels[c->chan_id]); |
| 94 | } |
| 95 | |
| 96 | /* Execute all queued DMA descriptors */ |
| 97 | static void sirfsoc_dma_execute(struct sirfsoc_dma_chan *schan) |
| 98 | { |
| 99 | struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan); |
| 100 | int cid = schan->chan.chan_id; |
| 101 | struct sirfsoc_dma_desc *sdesc = NULL; |
| 102 | |
| 103 | /* |
| 104 | * lock has been held by functions calling this, so we don't hold |
| 105 | * lock again |
| 106 | */ |
| 107 | |
| 108 | sdesc = list_first_entry(&schan->queued, struct sirfsoc_dma_desc, |
| 109 | node); |
| 110 | /* Move the first queued descriptor to active list */ |
| 111 | list_move_tail(&schan->queued, &schan->active); |
| 112 | |
| 113 | /* Start the DMA transfer */ |
| 114 | writel_relaxed(sdesc->width, sdma->base + SIRFSOC_DMA_WIDTH_0 + |
| 115 | cid * 4); |
| 116 | writel_relaxed(cid | (schan->mode << SIRFSOC_DMA_MODE_CTRL_BIT) | |
| 117 | (sdesc->dir << SIRFSOC_DMA_DIR_CTRL_BIT), |
| 118 | sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_CTRL); |
| 119 | writel_relaxed(sdesc->xlen, sdma->base + cid * 0x10 + |
| 120 | SIRFSOC_DMA_CH_XLEN); |
| 121 | writel_relaxed(sdesc->ylen, sdma->base + cid * 0x10 + |
| 122 | SIRFSOC_DMA_CH_YLEN); |
| 123 | writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN) | |
| 124 | (1 << cid), sdma->base + SIRFSOC_DMA_INT_EN); |
| 125 | |
| 126 | /* |
| 127 | * writel has an implict memory write barrier to make sure data is |
| 128 | * flushed into memory before starting DMA |
| 129 | */ |
| 130 | writel(sdesc->addr >> 2, sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_ADDR); |
| 131 | |
| 132 | if (sdesc->cyclic) { |
| 133 | writel((1 << cid) | 1 << (cid + 16) | |
| 134 | readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL), |
| 135 | sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL); |
| 136 | schan->happened_cyclic = schan->completed_cyclic = 0; |
| 137 | } |
| 138 | } |
| 139 | |
| 140 | /* Interrupt handler */ |
| 141 | static irqreturn_t sirfsoc_dma_irq(int irq, void *data) |
| 142 | { |
| 143 | struct sirfsoc_dma *sdma = data; |
| 144 | struct sirfsoc_dma_chan *schan; |
| 145 | struct sirfsoc_dma_desc *sdesc = NULL; |
| 146 | u32 is; |
| 147 | int ch; |
| 148 | |
| 149 | is = readl(sdma->base + SIRFSOC_DMA_CH_INT); |
| 150 | while ((ch = fls(is) - 1) >= 0) { |
| 151 | is &= ~(1 << ch); |
| 152 | writel_relaxed(1 << ch, sdma->base + SIRFSOC_DMA_CH_INT); |
| 153 | schan = &sdma->channels[ch]; |
| 154 | |
| 155 | spin_lock(&schan->lock); |
| 156 | |
| 157 | sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc, |
| 158 | node); |
| 159 | if (!sdesc->cyclic) { |
| 160 | /* Execute queued descriptors */ |
| 161 | list_splice_tail_init(&schan->active, &schan->completed); |
| 162 | if (!list_empty(&schan->queued)) |
| 163 | sirfsoc_dma_execute(schan); |
| 164 | } else |
| 165 | schan->happened_cyclic++; |
| 166 | |
| 167 | spin_unlock(&schan->lock); |
| 168 | } |
| 169 | |
| 170 | /* Schedule tasklet */ |
| 171 | tasklet_schedule(&sdma->tasklet); |
| 172 | |
| 173 | return IRQ_HANDLED; |
| 174 | } |
| 175 | |
| 176 | /* process completed descriptors */ |
| 177 | static void sirfsoc_dma_process_completed(struct sirfsoc_dma *sdma) |
| 178 | { |
| 179 | dma_cookie_t last_cookie = 0; |
| 180 | struct sirfsoc_dma_chan *schan; |
| 181 | struct sirfsoc_dma_desc *sdesc; |
| 182 | struct dma_async_tx_descriptor *desc; |
| 183 | unsigned long flags; |
| 184 | unsigned long happened_cyclic; |
| 185 | LIST_HEAD(list); |
| 186 | int i; |
| 187 | |
| 188 | for (i = 0; i < sdma->dma.chancnt; i++) { |
| 189 | schan = &sdma->channels[i]; |
| 190 | |
| 191 | /* Get all completed descriptors */ |
| 192 | spin_lock_irqsave(&schan->lock, flags); |
| 193 | if (!list_empty(&schan->completed)) { |
| 194 | list_splice_tail_init(&schan->completed, &list); |
| 195 | spin_unlock_irqrestore(&schan->lock, flags); |
| 196 | |
| 197 | /* Execute callbacks and run dependencies */ |
| 198 | list_for_each_entry(sdesc, &list, node) { |
| 199 | desc = &sdesc->desc; |
| 200 | |
| 201 | if (desc->callback) |
| 202 | desc->callback(desc->callback_param); |
| 203 | |
| 204 | last_cookie = desc->cookie; |
| 205 | dma_run_dependencies(desc); |
| 206 | } |
| 207 | |
| 208 | /* Free descriptors */ |
| 209 | spin_lock_irqsave(&schan->lock, flags); |
| 210 | list_splice_tail_init(&list, &schan->free); |
| 211 | schan->completed_cookie = last_cookie; |
| 212 | spin_unlock_irqrestore(&schan->lock, flags); |
| 213 | } else { |
| 214 | /* for cyclic channel, desc is always in active list */ |
| 215 | sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc, |
| 216 | node); |
| 217 | |
| 218 | if (!sdesc || (sdesc && !sdesc->cyclic)) { |
| 219 | /* without active cyclic DMA */ |
| 220 | spin_unlock_irqrestore(&schan->lock, flags); |
| 221 | continue; |
| 222 | } |
| 223 | |
| 224 | /* cyclic DMA */ |
| 225 | happened_cyclic = schan->happened_cyclic; |
| 226 | spin_unlock_irqrestore(&schan->lock, flags); |
| 227 | |
| 228 | desc = &sdesc->desc; |
| 229 | while (happened_cyclic != schan->completed_cyclic) { |
| 230 | if (desc->callback) |
| 231 | desc->callback(desc->callback_param); |
| 232 | schan->completed_cyclic++; |
| 233 | } |
| 234 | } |
| 235 | } |
| 236 | } |
| 237 | |
| 238 | /* DMA Tasklet */ |
| 239 | static void sirfsoc_dma_tasklet(unsigned long data) |
| 240 | { |
| 241 | struct sirfsoc_dma *sdma = (void *)data; |
| 242 | |
| 243 | sirfsoc_dma_process_completed(sdma); |
| 244 | } |
| 245 | |
| 246 | /* Submit descriptor to hardware */ |
| 247 | static dma_cookie_t sirfsoc_dma_tx_submit(struct dma_async_tx_descriptor *txd) |
| 248 | { |
| 249 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(txd->chan); |
| 250 | struct sirfsoc_dma_desc *sdesc; |
| 251 | unsigned long flags; |
| 252 | dma_cookie_t cookie; |
| 253 | |
| 254 | sdesc = container_of(txd, struct sirfsoc_dma_desc, desc); |
| 255 | |
| 256 | spin_lock_irqsave(&schan->lock, flags); |
| 257 | |
| 258 | /* Move descriptor to queue */ |
| 259 | list_move_tail(&sdesc->node, &schan->queued); |
| 260 | |
| 261 | /* Update cookie */ |
| 262 | cookie = schan->chan.cookie + 1; |
| 263 | if (cookie <= 0) |
| 264 | cookie = 1; |
| 265 | |
| 266 | schan->chan.cookie = cookie; |
| 267 | sdesc->desc.cookie = cookie; |
| 268 | |
| 269 | spin_unlock_irqrestore(&schan->lock, flags); |
| 270 | |
| 271 | return cookie; |
| 272 | } |
| 273 | |
| 274 | static int sirfsoc_dma_slave_config(struct sirfsoc_dma_chan *schan, |
| 275 | struct dma_slave_config *config) |
| 276 | { |
| 277 | unsigned long flags; |
| 278 | |
| 279 | if ((config->src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) || |
| 280 | (config->dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES)) |
| 281 | return -EINVAL; |
| 282 | |
| 283 | spin_lock_irqsave(&schan->lock, flags); |
| 284 | schan->mode = (config->src_maxburst == 4 ? 1 : 0); |
| 285 | spin_unlock_irqrestore(&schan->lock, flags); |
| 286 | |
| 287 | return 0; |
| 288 | } |
| 289 | |
| 290 | static int sirfsoc_dma_terminate_all(struct sirfsoc_dma_chan *schan) |
| 291 | { |
| 292 | struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan); |
| 293 | int cid = schan->chan.chan_id; |
| 294 | unsigned long flags; |
| 295 | |
| 296 | writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN) & |
| 297 | ~(1 << cid), sdma->base + SIRFSOC_DMA_INT_EN); |
| 298 | writel_relaxed(1 << cid, sdma->base + SIRFSOC_DMA_CH_VALID); |
| 299 | |
| 300 | writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL) |
| 301 | & ~((1 << cid) | 1 << (cid + 16)), |
| 302 | sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL); |
| 303 | |
| 304 | spin_lock_irqsave(&schan->lock, flags); |
| 305 | list_splice_tail_init(&schan->active, &schan->free); |
| 306 | list_splice_tail_init(&schan->queued, &schan->free); |
| 307 | spin_unlock_irqrestore(&schan->lock, flags); |
| 308 | |
| 309 | return 0; |
| 310 | } |
| 311 | |
| 312 | static int sirfsoc_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, |
| 313 | unsigned long arg) |
| 314 | { |
| 315 | struct dma_slave_config *config; |
| 316 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan); |
| 317 | |
| 318 | switch (cmd) { |
| 319 | case DMA_TERMINATE_ALL: |
| 320 | return sirfsoc_dma_terminate_all(schan); |
| 321 | case DMA_SLAVE_CONFIG: |
| 322 | config = (struct dma_slave_config *)arg; |
| 323 | return sirfsoc_dma_slave_config(schan, config); |
| 324 | |
| 325 | default: |
| 326 | break; |
| 327 | } |
| 328 | |
| 329 | return -ENOSYS; |
| 330 | } |
| 331 | |
| 332 | /* Alloc channel resources */ |
| 333 | static int sirfsoc_dma_alloc_chan_resources(struct dma_chan *chan) |
| 334 | { |
| 335 | struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan); |
| 336 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan); |
| 337 | struct sirfsoc_dma_desc *sdesc; |
| 338 | unsigned long flags; |
| 339 | LIST_HEAD(descs); |
| 340 | int i; |
| 341 | |
| 342 | /* Alloc descriptors for this channel */ |
| 343 | for (i = 0; i < SIRFSOC_DMA_DESCRIPTORS; i++) { |
| 344 | sdesc = kzalloc(sizeof(*sdesc), GFP_KERNEL); |
| 345 | if (!sdesc) { |
| 346 | dev_notice(sdma->dma.dev, "Memory allocation error. " |
| 347 | "Allocated only %u descriptors\n", i); |
| 348 | break; |
| 349 | } |
| 350 | |
| 351 | dma_async_tx_descriptor_init(&sdesc->desc, chan); |
| 352 | sdesc->desc.flags = DMA_CTRL_ACK; |
| 353 | sdesc->desc.tx_submit = sirfsoc_dma_tx_submit; |
| 354 | |
| 355 | list_add_tail(&sdesc->node, &descs); |
| 356 | } |
| 357 | |
| 358 | /* Return error only if no descriptors were allocated */ |
| 359 | if (i == 0) |
| 360 | return -ENOMEM; |
| 361 | |
| 362 | spin_lock_irqsave(&schan->lock, flags); |
| 363 | |
| 364 | list_splice_tail_init(&descs, &schan->free); |
| 365 | spin_unlock_irqrestore(&schan->lock, flags); |
| 366 | |
| 367 | return i; |
| 368 | } |
| 369 | |
| 370 | /* Free channel resources */ |
| 371 | static void sirfsoc_dma_free_chan_resources(struct dma_chan *chan) |
| 372 | { |
| 373 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan); |
| 374 | struct sirfsoc_dma_desc *sdesc, *tmp; |
| 375 | unsigned long flags; |
| 376 | LIST_HEAD(descs); |
| 377 | |
| 378 | spin_lock_irqsave(&schan->lock, flags); |
| 379 | |
| 380 | /* Channel must be idle */ |
| 381 | BUG_ON(!list_empty(&schan->prepared)); |
| 382 | BUG_ON(!list_empty(&schan->queued)); |
| 383 | BUG_ON(!list_empty(&schan->active)); |
| 384 | BUG_ON(!list_empty(&schan->completed)); |
| 385 | |
| 386 | /* Move data */ |
| 387 | list_splice_tail_init(&schan->free, &descs); |
| 388 | |
| 389 | spin_unlock_irqrestore(&schan->lock, flags); |
| 390 | |
| 391 | /* Free descriptors */ |
| 392 | list_for_each_entry_safe(sdesc, tmp, &descs, node) |
| 393 | kfree(sdesc); |
| 394 | } |
| 395 | |
| 396 | /* Send pending descriptor to hardware */ |
| 397 | static void sirfsoc_dma_issue_pending(struct dma_chan *chan) |
| 398 | { |
| 399 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan); |
| 400 | unsigned long flags; |
| 401 | |
| 402 | spin_lock_irqsave(&schan->lock, flags); |
| 403 | |
| 404 | if (list_empty(&schan->active) && !list_empty(&schan->queued)) |
| 405 | sirfsoc_dma_execute(schan); |
| 406 | |
| 407 | spin_unlock_irqrestore(&schan->lock, flags); |
| 408 | } |
| 409 | |
| 410 | /* Check request completion status */ |
| 411 | static enum dma_status |
| 412 | sirfsoc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie, |
| 413 | struct dma_tx_state *txstate) |
| 414 | { |
| 415 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan); |
| 416 | unsigned long flags; |
| 417 | dma_cookie_t last_used; |
| 418 | dma_cookie_t last_complete; |
| 419 | |
| 420 | spin_lock_irqsave(&schan->lock, flags); |
| 421 | last_used = schan->chan.cookie; |
| 422 | last_complete = schan->completed_cookie; |
| 423 | spin_unlock_irqrestore(&schan->lock, flags); |
| 424 | |
| 425 | dma_set_tx_state(txstate, last_complete, last_used, 0); |
| 426 | return dma_async_is_complete(cookie, last_complete, last_used); |
| 427 | } |
| 428 | |
| 429 | static struct dma_async_tx_descriptor *sirfsoc_dma_prep_interleaved( |
| 430 | struct dma_chan *chan, struct dma_interleaved_template *xt, |
| 431 | unsigned long flags) |
| 432 | { |
| 433 | struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan); |
| 434 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan); |
| 435 | struct sirfsoc_dma_desc *sdesc = NULL; |
| 436 | unsigned long iflags; |
| 437 | int ret; |
| 438 | |
| 439 | if ((xt->dir != DMA_MEM_TO_DEV) || (xt->dir != DMA_DEV_TO_MEM)) { |
| 440 | ret = -EINVAL; |
| 441 | goto err_dir; |
| 442 | } |
| 443 | |
| 444 | /* Get free descriptor */ |
| 445 | spin_lock_irqsave(&schan->lock, iflags); |
| 446 | if (!list_empty(&schan->free)) { |
| 447 | sdesc = list_first_entry(&schan->free, struct sirfsoc_dma_desc, |
| 448 | node); |
| 449 | list_del(&sdesc->node); |
| 450 | } |
| 451 | spin_unlock_irqrestore(&schan->lock, iflags); |
| 452 | |
| 453 | if (!sdesc) { |
| 454 | /* try to free completed descriptors */ |
| 455 | sirfsoc_dma_process_completed(sdma); |
| 456 | ret = 0; |
| 457 | goto no_desc; |
| 458 | } |
| 459 | |
| 460 | /* Place descriptor in prepared list */ |
| 461 | spin_lock_irqsave(&schan->lock, iflags); |
| 462 | |
| 463 | /* |
| 464 | * Number of chunks in a frame can only be 1 for prima2 |
| 465 | * and ylen (number of frame - 1) must be at least 0 |
| 466 | */ |
| 467 | if ((xt->frame_size == 1) && (xt->numf > 0)) { |
| 468 | sdesc->cyclic = 0; |
| 469 | sdesc->xlen = xt->sgl[0].size / SIRFSOC_DMA_WORD_LEN; |
| 470 | sdesc->width = (xt->sgl[0].size + xt->sgl[0].icg) / |
| 471 | SIRFSOC_DMA_WORD_LEN; |
| 472 | sdesc->ylen = xt->numf - 1; |
| 473 | if (xt->dir == DMA_MEM_TO_DEV) { |
| 474 | sdesc->addr = xt->src_start; |
| 475 | sdesc->dir = 1; |
| 476 | } else { |
| 477 | sdesc->addr = xt->dst_start; |
| 478 | sdesc->dir = 0; |
| 479 | } |
| 480 | |
| 481 | list_add_tail(&sdesc->node, &schan->prepared); |
| 482 | } else { |
| 483 | pr_err("sirfsoc DMA Invalid xfer\n"); |
| 484 | ret = -EINVAL; |
| 485 | goto err_xfer; |
| 486 | } |
| 487 | spin_unlock_irqrestore(&schan->lock, iflags); |
| 488 | |
| 489 | return &sdesc->desc; |
| 490 | err_xfer: |
| 491 | spin_unlock_irqrestore(&schan->lock, iflags); |
| 492 | no_desc: |
| 493 | err_dir: |
| 494 | return ERR_PTR(ret); |
| 495 | } |
| 496 | |
| 497 | static struct dma_async_tx_descriptor * |
| 498 | sirfsoc_dma_prep_cyclic(struct dma_chan *chan, dma_addr_t addr, |
| 499 | size_t buf_len, size_t period_len, |
| 500 | enum dma_transfer_direction direction) |
| 501 | { |
| 502 | struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan); |
| 503 | struct sirfsoc_dma_desc *sdesc = NULL; |
| 504 | unsigned long iflags; |
| 505 | |
| 506 | /* |
| 507 | * we only support cycle transfer with 2 period |
| 508 | * If the X-length is set to 0, it would be the loop mode. |
| 509 | * The DMA address keeps increasing until reaching the end of a loop |
| 510 | * area whose size is defined by (DMA_WIDTH x (Y_LENGTH + 1)). Then |
| 511 | * the DMA address goes back to the beginning of this area. |
| 512 | * In loop mode, the DMA data region is divided into two parts, BUFA |
| 513 | * and BUFB. DMA controller generates interrupts twice in each loop: |
| 514 | * when the DMA address reaches the end of BUFA or the end of the |
| 515 | * BUFB |
| 516 | */ |
| 517 | if (buf_len != 2 * period_len) |
| 518 | return ERR_PTR(-EINVAL); |
| 519 | |
| 520 | /* Get free descriptor */ |
| 521 | spin_lock_irqsave(&schan->lock, iflags); |
| 522 | if (!list_empty(&schan->free)) { |
| 523 | sdesc = list_first_entry(&schan->free, struct sirfsoc_dma_desc, |
| 524 | node); |
| 525 | list_del(&sdesc->node); |
| 526 | } |
| 527 | spin_unlock_irqrestore(&schan->lock, iflags); |
| 528 | |
| 529 | if (!sdesc) |
| 530 | return 0; |
| 531 | |
| 532 | /* Place descriptor in prepared list */ |
| 533 | spin_lock_irqsave(&schan->lock, iflags); |
| 534 | sdesc->addr = addr; |
| 535 | sdesc->cyclic = 1; |
| 536 | sdesc->xlen = 0; |
| 537 | sdesc->ylen = buf_len / SIRFSOC_DMA_WORD_LEN - 1; |
| 538 | sdesc->width = 1; |
| 539 | list_add_tail(&sdesc->node, &schan->prepared); |
| 540 | spin_unlock_irqrestore(&schan->lock, iflags); |
| 541 | |
| 542 | return &sdesc->desc; |
| 543 | } |
| 544 | |
| 545 | /* |
| 546 | * The DMA controller consists of 16 independent DMA channels. |
| 547 | * Each channel is allocated to a different function |
| 548 | */ |
| 549 | bool sirfsoc_dma_filter_id(struct dma_chan *chan, void *chan_id) |
| 550 | { |
| 551 | unsigned int ch_nr = (unsigned int) chan_id; |
| 552 | |
| 553 | if (ch_nr == chan->chan_id + |
| 554 | chan->device->dev_id * SIRFSOC_DMA_CHANNELS) |
| 555 | return true; |
| 556 | |
| 557 | return false; |
| 558 | } |
| 559 | EXPORT_SYMBOL(sirfsoc_dma_filter_id); |
| 560 | |
| 561 | static int __devinit sirfsoc_dma_probe(struct platform_device *op) |
| 562 | { |
| 563 | struct device_node *dn = op->dev.of_node; |
| 564 | struct device *dev = &op->dev; |
| 565 | struct dma_device *dma; |
| 566 | struct sirfsoc_dma *sdma; |
| 567 | struct sirfsoc_dma_chan *schan; |
| 568 | struct resource res; |
| 569 | ulong regs_start, regs_size; |
| 570 | u32 id; |
| 571 | int ret, i; |
| 572 | |
| 573 | sdma = devm_kzalloc(dev, sizeof(*sdma), GFP_KERNEL); |
| 574 | if (!sdma) { |
| 575 | dev_err(dev, "Memory exhausted!\n"); |
| 576 | return -ENOMEM; |
| 577 | } |
| 578 | |
| 579 | if (of_property_read_u32(dn, "cell-index", &id)) { |
| 580 | dev_err(dev, "Fail to get DMAC index\n"); |
| 581 | ret = -ENODEV; |
| 582 | goto free_mem; |
| 583 | } |
| 584 | |
| 585 | sdma->irq = irq_of_parse_and_map(dn, 0); |
| 586 | if (sdma->irq == NO_IRQ) { |
| 587 | dev_err(dev, "Error mapping IRQ!\n"); |
| 588 | ret = -EINVAL; |
| 589 | goto free_mem; |
| 590 | } |
| 591 | |
| 592 | ret = of_address_to_resource(dn, 0, &res); |
| 593 | if (ret) { |
| 594 | dev_err(dev, "Error parsing memory region!\n"); |
| 595 | goto free_mem; |
| 596 | } |
| 597 | |
| 598 | regs_start = res.start; |
| 599 | regs_size = resource_size(&res); |
| 600 | |
| 601 | sdma->base = devm_ioremap(dev, regs_start, regs_size); |
| 602 | if (!sdma->base) { |
| 603 | dev_err(dev, "Error mapping memory region!\n"); |
| 604 | ret = -ENOMEM; |
| 605 | goto irq_dispose; |
| 606 | } |
| 607 | |
| 608 | ret = devm_request_irq(dev, sdma->irq, &sirfsoc_dma_irq, 0, DRV_NAME, |
| 609 | sdma); |
| 610 | if (ret) { |
| 611 | dev_err(dev, "Error requesting IRQ!\n"); |
| 612 | ret = -EINVAL; |
| 613 | goto unmap_mem; |
| 614 | } |
| 615 | |
| 616 | dma = &sdma->dma; |
| 617 | dma->dev = dev; |
| 618 | dma->chancnt = SIRFSOC_DMA_CHANNELS; |
| 619 | |
| 620 | dma->device_alloc_chan_resources = sirfsoc_dma_alloc_chan_resources; |
| 621 | dma->device_free_chan_resources = sirfsoc_dma_free_chan_resources; |
| 622 | dma->device_issue_pending = sirfsoc_dma_issue_pending; |
| 623 | dma->device_control = sirfsoc_dma_control; |
| 624 | dma->device_tx_status = sirfsoc_dma_tx_status; |
| 625 | dma->device_prep_interleaved_dma = sirfsoc_dma_prep_interleaved; |
| 626 | dma->device_prep_dma_cyclic = sirfsoc_dma_prep_cyclic; |
| 627 | |
| 628 | INIT_LIST_HEAD(&dma->channels); |
| 629 | dma_cap_set(DMA_SLAVE, dma->cap_mask); |
| 630 | dma_cap_set(DMA_CYCLIC, dma->cap_mask); |
| 631 | dma_cap_set(DMA_INTERLEAVE, dma->cap_mask); |
| 632 | dma_cap_set(DMA_PRIVATE, dma->cap_mask); |
| 633 | |
| 634 | for (i = 0; i < dma->chancnt; i++) { |
| 635 | schan = &sdma->channels[i]; |
| 636 | |
| 637 | schan->chan.device = dma; |
| 638 | schan->chan.cookie = 1; |
| 639 | schan->completed_cookie = schan->chan.cookie; |
| 640 | |
| 641 | INIT_LIST_HEAD(&schan->free); |
| 642 | INIT_LIST_HEAD(&schan->prepared); |
| 643 | INIT_LIST_HEAD(&schan->queued); |
| 644 | INIT_LIST_HEAD(&schan->active); |
| 645 | INIT_LIST_HEAD(&schan->completed); |
| 646 | |
| 647 | spin_lock_init(&schan->lock); |
| 648 | list_add_tail(&schan->chan.device_node, &dma->channels); |
| 649 | } |
| 650 | |
| 651 | tasklet_init(&sdma->tasklet, sirfsoc_dma_tasklet, (unsigned long)sdma); |
| 652 | |
| 653 | /* Register DMA engine */ |
| 654 | dev_set_drvdata(dev, sdma); |
| 655 | ret = dma_async_device_register(dma); |
| 656 | if (ret) |
| 657 | goto free_irq; |
| 658 | |
| 659 | dev_info(dev, "initialized SIRFSOC DMAC driver\n"); |
| 660 | |
| 661 | return 0; |
| 662 | |
| 663 | free_irq: |
| 664 | devm_free_irq(dev, sdma->irq, sdma); |
| 665 | irq_dispose: |
| 666 | irq_dispose_mapping(sdma->irq); |
| 667 | unmap_mem: |
| 668 | iounmap(sdma->base); |
| 669 | free_mem: |
| 670 | devm_kfree(dev, sdma); |
| 671 | return ret; |
| 672 | } |
| 673 | |
| 674 | static int __devexit sirfsoc_dma_remove(struct platform_device *op) |
| 675 | { |
| 676 | struct device *dev = &op->dev; |
| 677 | struct sirfsoc_dma *sdma = dev_get_drvdata(dev); |
| 678 | |
| 679 | dma_async_device_unregister(&sdma->dma); |
| 680 | devm_free_irq(dev, sdma->irq, sdma); |
| 681 | irq_dispose_mapping(sdma->irq); |
| 682 | iounmap(sdma->base); |
| 683 | devm_kfree(dev, sdma); |
| 684 | return 0; |
| 685 | } |
| 686 | |
| 687 | static struct of_device_id sirfsoc_dma_match[] = { |
| 688 | { .compatible = "sirf,prima2-dmac", }, |
| 689 | {}, |
| 690 | }; |
| 691 | |
| 692 | static struct platform_driver sirfsoc_dma_driver = { |
| 693 | .probe = sirfsoc_dma_probe, |
| 694 | .remove = __devexit_p(sirfsoc_dma_remove), |
| 695 | .driver = { |
| 696 | .name = DRV_NAME, |
| 697 | .owner = THIS_MODULE, |
| 698 | .of_match_table = sirfsoc_dma_match, |
| 699 | }, |
| 700 | }; |
| 701 | |
Axel Lin | c94e910 | 2011-11-26 15:11:12 +0800 | [diff] [blame] | 702 | module_platform_driver(sirfsoc_dma_driver); |
Rongjun Ying | ca21a14 | 2011-10-27 19:22:39 -0700 | [diff] [blame] | 703 | |
| 704 | MODULE_AUTHOR("Rongjun Ying <rongjun.ying@csr.com>, " |
| 705 | "Barry Song <baohua.song@csr.com>"); |
| 706 | MODULE_DESCRIPTION("SIRFSOC DMA control driver"); |
| 707 | MODULE_LICENSE("GPL v2"); |