1 /* 2 * timb_dma.c timberdale FPGA DMA driver 3 * Copyright (c) 2010 Intel Corporation 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 17 */ 18 19 /* Supports: 20 * Timberdale FPGA DMA engine 21 */ 22 23 #include <linux/dmaengine.h> 24 #include <linux/dma-mapping.h> 25 #include <linux/init.h> 26 #include <linux/interrupt.h> 27 #include <linux/io.h> 28 #include <linux/module.h> 29 #include <linux/platform_device.h> 30 #include <linux/slab.h> 31 32 #include <linux/timb_dma.h> 33 34 #define DRIVER_NAME "timb-dma" 35 36 /* Global DMA registers */ 37 #define TIMBDMA_ACR 0x34 38 #define TIMBDMA_32BIT_ADDR 0x01 39 40 #define TIMBDMA_ISR 0x080000 41 #define TIMBDMA_IPR 0x080004 42 #define TIMBDMA_IER 0x080008 43 44 /* Channel specific registers */ 45 /* RX instances base addresses are 0x00, 0x40, 0x80 ... 46 * TX instances base addresses are 0x18, 0x58, 0x98 ... 47 */ 48 #define TIMBDMA_INSTANCE_OFFSET 0x40 49 #define TIMBDMA_INSTANCE_TX_OFFSET 0x18 50 51 /* RX registers, relative the instance base */ 52 #define TIMBDMA_OFFS_RX_DHAR 0x00 53 #define TIMBDMA_OFFS_RX_DLAR 0x04 54 #define TIMBDMA_OFFS_RX_LR 0x0C 55 #define TIMBDMA_OFFS_RX_BLR 0x10 56 #define TIMBDMA_OFFS_RX_ER 0x14 57 #define TIMBDMA_RX_EN 0x01 58 /* bytes per Row, video specific register 59 * which is placed after the TX registers... 60 */ 61 #define TIMBDMA_OFFS_RX_BPRR 0x30 62 63 /* TX registers, relative the instance base */ 64 #define TIMBDMA_OFFS_TX_DHAR 0x00 65 #define TIMBDMA_OFFS_TX_DLAR 0x04 66 #define TIMBDMA_OFFS_TX_BLR 0x0C 67 #define TIMBDMA_OFFS_TX_LR 0x14 68 69 70 #define TIMB_DMA_DESC_SIZE 8 71 72 struct timb_dma_desc { 73 struct list_head desc_node; 74 struct dma_async_tx_descriptor txd; 75 u8 *desc_list; 76 unsigned int desc_list_len; 77 bool interrupt; 78 }; 79 80 struct timb_dma_chan { 81 struct dma_chan chan; 82 void __iomem *membase; 83 spinlock_t lock; /* Used to protect data structures, 84 especially the lists and descriptors, 85 from races between the tasklet and calls 86 from above */ 87 dma_cookie_t last_completed_cookie; 88 bool ongoing; 89 struct list_head active_list; 90 struct list_head queue; 91 struct list_head free_list; 92 unsigned int bytes_per_line; 93 enum dma_data_direction direction; 94 unsigned int descs; /* Descriptors to allocate */ 95 unsigned int desc_elems; /* number of elems per descriptor */ 96 }; 97 98 struct timb_dma { 99 struct dma_device dma; 100 void __iomem *membase; 101 struct tasklet_struct tasklet; 102 struct timb_dma_chan channels[0]; 103 }; 104 105 static struct device *chan2dev(struct dma_chan *chan) 106 { 107 return &chan->dev->device; 108 } 109 static struct device *chan2dmadev(struct dma_chan *chan) 110 { 111 return chan2dev(chan)->parent->parent; 112 } 113 114 static struct timb_dma *tdchantotd(struct timb_dma_chan *td_chan) 115 { 116 int id = td_chan->chan.chan_id; 117 return (struct timb_dma *)((u8 *)td_chan - 118 id * sizeof(struct timb_dma_chan) - sizeof(struct timb_dma)); 119 } 120 121 /* Must be called with the spinlock held */ 122 static void __td_enable_chan_irq(struct timb_dma_chan *td_chan) 123 { 124 int id = td_chan->chan.chan_id; 125 struct timb_dma *td = tdchantotd(td_chan); 126 u32 ier; 127 128 /* enable interrupt for this channel */ 129 ier = ioread32(td->membase + TIMBDMA_IER); 130 ier |= 1 << id; 131 dev_dbg(chan2dev(&td_chan->chan), "Enabling irq: %d, IER: 0x%x\n", id, 132 ier); 133 iowrite32(ier, td->membase + TIMBDMA_IER); 134 } 135 136 /* Should be called with the spinlock held */ 137 static bool __td_dma_done_ack(struct timb_dma_chan *td_chan) 138 { 139 int id = td_chan->chan.chan_id; 140 struct timb_dma *td = (struct timb_dma *)((u8 *)td_chan - 141 id * sizeof(struct timb_dma_chan) - sizeof(struct timb_dma)); 142 u32 isr; 143 bool done = false; 144 145 dev_dbg(chan2dev(&td_chan->chan), "Checking irq: %d, td: %p\n", id, td); 146 147 isr = ioread32(td->membase + TIMBDMA_ISR) & (1 << id); 148 if (isr) { 149 iowrite32(isr, td->membase + TIMBDMA_ISR); 150 done = true; 151 } 152 153 return done; 154 } 155 156 static void __td_unmap_desc(struct timb_dma_chan *td_chan, const u8 *dma_desc, 157 bool single) 158 { 159 dma_addr_t addr; 160 int len; 161 162 addr = (dma_desc[7] << 24) | (dma_desc[6] << 16) | (dma_desc[5] << 8) | 163 dma_desc[4]; 164 165 len = (dma_desc[3] << 8) | dma_desc[2]; 166 167 if (single) 168 dma_unmap_single(chan2dev(&td_chan->chan), addr, len, 169 td_chan->direction); 170 else 171 dma_unmap_page(chan2dev(&td_chan->chan), addr, len, 172 td_chan->direction); 173 } 174 175 static void __td_unmap_descs(struct timb_dma_desc *td_desc, bool single) 176 { 177 struct timb_dma_chan *td_chan = container_of(td_desc->txd.chan, 178 struct timb_dma_chan, chan); 179 u8 *descs; 180 181 for (descs = td_desc->desc_list; ; descs += TIMB_DMA_DESC_SIZE) { 182 __td_unmap_desc(td_chan, descs, single); 183 if (descs[0] & 0x02) 184 break; 185 } 186 } 187 188 static int td_fill_desc(struct timb_dma_chan *td_chan, u8 *dma_desc, 189 struct scatterlist *sg, bool last) 190 { 191 if (sg_dma_len(sg) > USHRT_MAX) { 192 dev_err(chan2dev(&td_chan->chan), "Too big sg element\n"); 193 return -EINVAL; 194 } 195 196 /* length must be word aligned */ 197 if (sg_dma_len(sg) % sizeof(u32)) { 198 dev_err(chan2dev(&td_chan->chan), "Incorrect length: %d\n", 199 sg_dma_len(sg)); 200 return -EINVAL; 201 } 202 203 dev_dbg(chan2dev(&td_chan->chan), "desc: %p, addr: 0x%llx\n", 204 dma_desc, (unsigned long long)sg_dma_address(sg)); 205 206 dma_desc[7] = (sg_dma_address(sg) >> 24) & 0xff; 207 dma_desc[6] = (sg_dma_address(sg) >> 16) & 0xff; 208 dma_desc[5] = (sg_dma_address(sg) >> 8) & 0xff; 209 dma_desc[4] = (sg_dma_address(sg) >> 0) & 0xff; 210 211 dma_desc[3] = (sg_dma_len(sg) >> 8) & 0xff; 212 dma_desc[2] = (sg_dma_len(sg) >> 0) & 0xff; 213 214 dma_desc[1] = 0x00; 215 dma_desc[0] = 0x21 | (last ? 0x02 : 0); /* tran, valid */ 216 217 return 0; 218 } 219 220 /* Must be called with the spinlock held */ 221 static void __td_start_dma(struct timb_dma_chan *td_chan) 222 { 223 struct timb_dma_desc *td_desc; 224 225 if (td_chan->ongoing) { 226 dev_err(chan2dev(&td_chan->chan), 227 "Transfer already ongoing\n"); 228 return; 229 } 230 231 td_desc = list_entry(td_chan->active_list.next, struct timb_dma_desc, 232 desc_node); 233 234 dev_dbg(chan2dev(&td_chan->chan), 235 "td_chan: %p, chan: %d, membase: %p\n", 236 td_chan, td_chan->chan.chan_id, td_chan->membase); 237 238 if (td_chan->direction == DMA_FROM_DEVICE) { 239 240 /* descriptor address */ 241 iowrite32(0, td_chan->membase + TIMBDMA_OFFS_RX_DHAR); 242 iowrite32(td_desc->txd.phys, td_chan->membase + 243 TIMBDMA_OFFS_RX_DLAR); 244 /* Bytes per line */ 245 iowrite32(td_chan->bytes_per_line, td_chan->membase + 246 TIMBDMA_OFFS_RX_BPRR); 247 /* enable RX */ 248 iowrite32(TIMBDMA_RX_EN, td_chan->membase + TIMBDMA_OFFS_RX_ER); 249 } else { 250 /* address high */ 251 iowrite32(0, td_chan->membase + TIMBDMA_OFFS_TX_DHAR); 252 iowrite32(td_desc->txd.phys, td_chan->membase + 253 TIMBDMA_OFFS_TX_DLAR); 254 } 255 256 td_chan->ongoing = true; 257 258 if (td_desc->interrupt) 259 __td_enable_chan_irq(td_chan); 260 } 261 262 static void __td_finish(struct timb_dma_chan *td_chan) 263 { 264 dma_async_tx_callback callback; 265 void *param; 266 struct dma_async_tx_descriptor *txd; 267 struct timb_dma_desc *td_desc; 268 269 /* can happen if the descriptor is canceled */ 270 if (list_empty(&td_chan->active_list)) 271 return; 272 273 td_desc = list_entry(td_chan->active_list.next, struct timb_dma_desc, 274 desc_node); 275 txd = &td_desc->txd; 276 277 dev_dbg(chan2dev(&td_chan->chan), "descriptor %u complete\n", 278 txd->cookie); 279 280 /* make sure to stop the transfer */ 281 if (td_chan->direction == DMA_FROM_DEVICE) 282 iowrite32(0, td_chan->membase + TIMBDMA_OFFS_RX_ER); 283 /* Currently no support for stopping DMA transfers 284 else 285 iowrite32(0, td_chan->membase + TIMBDMA_OFFS_TX_DLAR); 286 */ 287 td_chan->last_completed_cookie = txd->cookie; 288 td_chan->ongoing = false; 289 290 callback = txd->callback; 291 param = txd->callback_param; 292 293 list_move(&td_desc->desc_node, &td_chan->free_list); 294 295 if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) 296 __td_unmap_descs(td_desc, 297 txd->flags & DMA_COMPL_SRC_UNMAP_SINGLE); 298 299 /* 300 * The API requires that no submissions are done from a 301 * callback, so we don't need to drop the lock here 302 */ 303 if (callback) 304 callback(param); 305 } 306 307 static u32 __td_ier_mask(struct timb_dma *td) 308 { 309 int i; 310 u32 ret = 0; 311 312 for (i = 0; i < td->dma.chancnt; i++) { 313 struct timb_dma_chan *td_chan = td->channels + i; 314 if (td_chan->ongoing) { 315 struct timb_dma_desc *td_desc = 316 list_entry(td_chan->active_list.next, 317 struct timb_dma_desc, desc_node); 318 if (td_desc->interrupt) 319 ret |= 1 << i; 320 } 321 } 322 323 return ret; 324 } 325 326 static void __td_start_next(struct timb_dma_chan *td_chan) 327 { 328 struct timb_dma_desc *td_desc; 329 330 BUG_ON(list_empty(&td_chan->queue)); 331 BUG_ON(td_chan->ongoing); 332 333 td_desc = list_entry(td_chan->queue.next, struct timb_dma_desc, 334 desc_node); 335 336 dev_dbg(chan2dev(&td_chan->chan), "%s: started %u\n", 337 __func__, td_desc->txd.cookie); 338 339 list_move(&td_desc->desc_node, &td_chan->active_list); 340 __td_start_dma(td_chan); 341 } 342 343 static dma_cookie_t td_tx_submit(struct dma_async_tx_descriptor *txd) 344 { 345 struct timb_dma_desc *td_desc = container_of(txd, struct timb_dma_desc, 346 txd); 347 struct timb_dma_chan *td_chan = container_of(txd->chan, 348 struct timb_dma_chan, chan); 349 dma_cookie_t cookie; 350 351 spin_lock_bh(&td_chan->lock); 352 353 cookie = txd->chan->cookie; 354 if (++cookie < 0) 355 cookie = 1; 356 txd->chan->cookie = cookie; 357 txd->cookie = cookie; 358 359 if (list_empty(&td_chan->active_list)) { 360 dev_dbg(chan2dev(txd->chan), "%s: started %u\n", __func__, 361 txd->cookie); 362 list_add_tail(&td_desc->desc_node, &td_chan->active_list); 363 __td_start_dma(td_chan); 364 } else { 365 dev_dbg(chan2dev(txd->chan), "tx_submit: queued %u\n", 366 txd->cookie); 367 368 list_add_tail(&td_desc->desc_node, &td_chan->queue); 369 } 370 371 spin_unlock_bh(&td_chan->lock); 372 373 return cookie; 374 } 375 376 static struct timb_dma_desc *td_alloc_init_desc(struct timb_dma_chan *td_chan) 377 { 378 struct dma_chan *chan = &td_chan->chan; 379 struct timb_dma_desc *td_desc; 380 int err; 381 382 td_desc = kzalloc(sizeof(struct timb_dma_desc), GFP_KERNEL); 383 if (!td_desc) { 384 dev_err(chan2dev(chan), "Failed to alloc descriptor\n"); 385 goto out; 386 } 387 388 td_desc->desc_list_len = td_chan->desc_elems * TIMB_DMA_DESC_SIZE; 389 390 td_desc->desc_list = kzalloc(td_desc->desc_list_len, GFP_KERNEL); 391 if (!td_desc->desc_list) { 392 dev_err(chan2dev(chan), "Failed to alloc descriptor\n"); 393 goto err; 394 } 395 396 dma_async_tx_descriptor_init(&td_desc->txd, chan); 397 td_desc->txd.tx_submit = td_tx_submit; 398 td_desc->txd.flags = DMA_CTRL_ACK; 399 400 td_desc->txd.phys = dma_map_single(chan2dmadev(chan), 401 td_desc->desc_list, td_desc->desc_list_len, DMA_TO_DEVICE); 402 403 err = dma_mapping_error(chan2dmadev(chan), td_desc->txd.phys); 404 if (err) { 405 dev_err(chan2dev(chan), "DMA mapping error: %d\n", err); 406 goto err; 407 } 408 409 return td_desc; 410 err: 411 kfree(td_desc->desc_list); 412 kfree(td_desc); 413 out: 414 return NULL; 415 416 } 417 418 static void td_free_desc(struct timb_dma_desc *td_desc) 419 { 420 dev_dbg(chan2dev(td_desc->txd.chan), "Freeing desc: %p\n", td_desc); 421 dma_unmap_single(chan2dmadev(td_desc->txd.chan), td_desc->txd.phys, 422 td_desc->desc_list_len, DMA_TO_DEVICE); 423 424 kfree(td_desc->desc_list); 425 kfree(td_desc); 426 } 427 428 static void td_desc_put(struct timb_dma_chan *td_chan, 429 struct timb_dma_desc *td_desc) 430 { 431 dev_dbg(chan2dev(&td_chan->chan), "Putting desc: %p\n", td_desc); 432 433 spin_lock_bh(&td_chan->lock); 434 list_add(&td_desc->desc_node, &td_chan->free_list); 435 spin_unlock_bh(&td_chan->lock); 436 } 437 438 static struct timb_dma_desc *td_desc_get(struct timb_dma_chan *td_chan) 439 { 440 struct timb_dma_desc *td_desc, *_td_desc; 441 struct timb_dma_desc *ret = NULL; 442 443 spin_lock_bh(&td_chan->lock); 444 list_for_each_entry_safe(td_desc, _td_desc, &td_chan->free_list, 445 desc_node) { 446 if (async_tx_test_ack(&td_desc->txd)) { 447 list_del(&td_desc->desc_node); 448 ret = td_desc; 449 break; 450 } 451 dev_dbg(chan2dev(&td_chan->chan), "desc %p not ACKed\n", 452 td_desc); 453 } 454 spin_unlock_bh(&td_chan->lock); 455 456 return ret; 457 } 458 459 static int td_alloc_chan_resources(struct dma_chan *chan) 460 { 461 struct timb_dma_chan *td_chan = 462 container_of(chan, struct timb_dma_chan, chan); 463 int i; 464 465 dev_dbg(chan2dev(chan), "%s: entry\n", __func__); 466 467 BUG_ON(!list_empty(&td_chan->free_list)); 468 for (i = 0; i < td_chan->descs; i++) { 469 struct timb_dma_desc *td_desc = td_alloc_init_desc(td_chan); 470 if (!td_desc) { 471 if (i) 472 break; 473 else { 474 dev_err(chan2dev(chan), 475 "Couldnt allocate any descriptors\n"); 476 return -ENOMEM; 477 } 478 } 479 480 td_desc_put(td_chan, td_desc); 481 } 482 483 spin_lock_bh(&td_chan->lock); 484 td_chan->last_completed_cookie = 1; 485 chan->cookie = 1; 486 spin_unlock_bh(&td_chan->lock); 487 488 return 0; 489 } 490 491 static void td_free_chan_resources(struct dma_chan *chan) 492 { 493 struct timb_dma_chan *td_chan = 494 container_of(chan, struct timb_dma_chan, chan); 495 struct timb_dma_desc *td_desc, *_td_desc; 496 LIST_HEAD(list); 497 498 dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); 499 500 /* check that all descriptors are free */ 501 BUG_ON(!list_empty(&td_chan->active_list)); 502 BUG_ON(!list_empty(&td_chan->queue)); 503 504 spin_lock_bh(&td_chan->lock); 505 list_splice_init(&td_chan->free_list, &list); 506 spin_unlock_bh(&td_chan->lock); 507 508 list_for_each_entry_safe(td_desc, _td_desc, &list, desc_node) { 509 dev_dbg(chan2dev(chan), "%s: Freeing desc: %p\n", __func__, 510 td_desc); 511 td_free_desc(td_desc); 512 } 513 } 514 515 static enum dma_status td_tx_status(struct dma_chan *chan, dma_cookie_t cookie, 516 struct dma_tx_state *txstate) 517 { 518 struct timb_dma_chan *td_chan = 519 container_of(chan, struct timb_dma_chan, chan); 520 dma_cookie_t last_used; 521 dma_cookie_t last_complete; 522 int ret; 523 524 dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); 525 526 last_complete = td_chan->last_completed_cookie; 527 last_used = chan->cookie; 528 529 ret = dma_async_is_complete(cookie, last_complete, last_used); 530 531 dma_set_tx_state(txstate, last_complete, last_used, 0); 532 533 dev_dbg(chan2dev(chan), 534 "%s: exit, ret: %d, last_complete: %d, last_used: %d\n", 535 __func__, ret, last_complete, last_used); 536 537 return ret; 538 } 539 540 static void td_issue_pending(struct dma_chan *chan) 541 { 542 struct timb_dma_chan *td_chan = 543 container_of(chan, struct timb_dma_chan, chan); 544 545 dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); 546 spin_lock_bh(&td_chan->lock); 547 548 if (!list_empty(&td_chan->active_list)) 549 /* transfer ongoing */ 550 if (__td_dma_done_ack(td_chan)) 551 __td_finish(td_chan); 552 553 if (list_empty(&td_chan->active_list) && !list_empty(&td_chan->queue)) 554 __td_start_next(td_chan); 555 556 spin_unlock_bh(&td_chan->lock); 557 } 558 559 static struct dma_async_tx_descriptor *td_prep_slave_sg(struct dma_chan *chan, 560 struct scatterlist *sgl, unsigned int sg_len, 561 enum dma_data_direction direction, unsigned long flags) 562 { 563 struct timb_dma_chan *td_chan = 564 container_of(chan, struct timb_dma_chan, chan); 565 struct timb_dma_desc *td_desc; 566 struct scatterlist *sg; 567 unsigned int i; 568 unsigned int desc_usage = 0; 569 570 if (!sgl || !sg_len) { 571 dev_err(chan2dev(chan), "%s: No SG list\n", __func__); 572 return NULL; 573 } 574 575 /* even channels are for RX, odd for TX */ 576 if (td_chan->direction != direction) { 577 dev_err(chan2dev(chan), 578 "Requesting channel in wrong direction\n"); 579 return NULL; 580 } 581 582 td_desc = td_desc_get(td_chan); 583 if (!td_desc) { 584 dev_err(chan2dev(chan), "Not enough descriptors available\n"); 585 return NULL; 586 } 587 588 td_desc->interrupt = (flags & DMA_PREP_INTERRUPT) != 0; 589 590 for_each_sg(sgl, sg, sg_len, i) { 591 int err; 592 if (desc_usage > td_desc->desc_list_len) { 593 dev_err(chan2dev(chan), "No descriptor space\n"); 594 return NULL; 595 } 596 597 err = td_fill_desc(td_chan, td_desc->desc_list + desc_usage, sg, 598 i == (sg_len - 1)); 599 if (err) { 600 dev_err(chan2dev(chan), "Failed to update desc: %d\n", 601 err); 602 td_desc_put(td_chan, td_desc); 603 return NULL; 604 } 605 desc_usage += TIMB_DMA_DESC_SIZE; 606 } 607 608 dma_sync_single_for_device(chan2dmadev(chan), td_desc->txd.phys, 609 td_desc->desc_list_len, DMA_TO_DEVICE); 610 611 return &td_desc->txd; 612 } 613 614 static int td_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, 615 unsigned long arg) 616 { 617 struct timb_dma_chan *td_chan = 618 container_of(chan, struct timb_dma_chan, chan); 619 struct timb_dma_desc *td_desc, *_td_desc; 620 621 dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); 622 623 if (cmd != DMA_TERMINATE_ALL) 624 return -ENXIO; 625 626 /* first the easy part, put the queue into the free list */ 627 spin_lock_bh(&td_chan->lock); 628 list_for_each_entry_safe(td_desc, _td_desc, &td_chan->queue, 629 desc_node) 630 list_move(&td_desc->desc_node, &td_chan->free_list); 631 632 /* now tear down the running */ 633 __td_finish(td_chan); 634 spin_unlock_bh(&td_chan->lock); 635 636 return 0; 637 } 638 639 static void td_tasklet(unsigned long data) 640 { 641 struct timb_dma *td = (struct timb_dma *)data; 642 u32 isr; 643 u32 ipr; 644 u32 ier; 645 int i; 646 647 isr = ioread32(td->membase + TIMBDMA_ISR); 648 ipr = isr & __td_ier_mask(td); 649 650 /* ack the interrupts */ 651 iowrite32(ipr, td->membase + TIMBDMA_ISR); 652 653 for (i = 0; i < td->dma.chancnt; i++) 654 if (ipr & (1 << i)) { 655 struct timb_dma_chan *td_chan = td->channels + i; 656 spin_lock(&td_chan->lock); 657 __td_finish(td_chan); 658 if (!list_empty(&td_chan->queue)) 659 __td_start_next(td_chan); 660 spin_unlock(&td_chan->lock); 661 } 662 663 ier = __td_ier_mask(td); 664 iowrite32(ier, td->membase + TIMBDMA_IER); 665 } 666 667 668 static irqreturn_t td_irq(int irq, void *devid) 669 { 670 struct timb_dma *td = devid; 671 u32 ipr = ioread32(td->membase + TIMBDMA_IPR); 672 673 if (ipr) { 674 /* disable interrupts, will be re-enabled in tasklet */ 675 iowrite32(0, td->membase + TIMBDMA_IER); 676 677 tasklet_schedule(&td->tasklet); 678 679 return IRQ_HANDLED; 680 } else 681 return IRQ_NONE; 682 } 683 684 685 static int __devinit td_probe(struct platform_device *pdev) 686 { 687 struct timb_dma_platform_data *pdata = pdev->dev.platform_data; 688 struct timb_dma *td; 689 struct resource *iomem; 690 int irq; 691 int err; 692 int i; 693 694 if (!pdata) { 695 dev_err(&pdev->dev, "No platform data\n"); 696 return -EINVAL; 697 } 698 699 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 700 if (!iomem) 701 return -EINVAL; 702 703 irq = platform_get_irq(pdev, 0); 704 if (irq < 0) 705 return irq; 706 707 if (!request_mem_region(iomem->start, resource_size(iomem), 708 DRIVER_NAME)) 709 return -EBUSY; 710 711 td = kzalloc(sizeof(struct timb_dma) + 712 sizeof(struct timb_dma_chan) * pdata->nr_channels, GFP_KERNEL); 713 if (!td) { 714 err = -ENOMEM; 715 goto err_release_region; 716 } 717 718 dev_dbg(&pdev->dev, "Allocated TD: %p\n", td); 719 720 td->membase = ioremap(iomem->start, resource_size(iomem)); 721 if (!td->membase) { 722 dev_err(&pdev->dev, "Failed to remap I/O memory\n"); 723 err = -ENOMEM; 724 goto err_free_mem; 725 } 726 727 /* 32bit addressing */ 728 iowrite32(TIMBDMA_32BIT_ADDR, td->membase + TIMBDMA_ACR); 729 730 /* disable and clear any interrupts */ 731 iowrite32(0x0, td->membase + TIMBDMA_IER); 732 iowrite32(0xFFFFFFFF, td->membase + TIMBDMA_ISR); 733 734 tasklet_init(&td->tasklet, td_tasklet, (unsigned long)td); 735 736 err = request_irq(irq, td_irq, IRQF_SHARED, DRIVER_NAME, td); 737 if (err) { 738 dev_err(&pdev->dev, "Failed to request IRQ\n"); 739 goto err_tasklet_kill; 740 } 741 742 td->dma.device_alloc_chan_resources = td_alloc_chan_resources; 743 td->dma.device_free_chan_resources = td_free_chan_resources; 744 td->dma.device_tx_status = td_tx_status; 745 td->dma.device_issue_pending = td_issue_pending; 746 747 dma_cap_set(DMA_SLAVE, td->dma.cap_mask); 748 dma_cap_set(DMA_PRIVATE, td->dma.cap_mask); 749 td->dma.device_prep_slave_sg = td_prep_slave_sg; 750 td->dma.device_control = td_control; 751 752 td->dma.dev = &pdev->dev; 753 754 INIT_LIST_HEAD(&td->dma.channels); 755 756 for (i = 0; i < pdata->nr_channels; i++, td->dma.chancnt++) { 757 struct timb_dma_chan *td_chan = &td->channels[i]; 758 struct timb_dma_platform_data_channel *pchan = 759 pdata->channels + i; 760 761 /* even channels are RX, odd are TX */ 762 if ((i % 2) == pchan->rx) { 763 dev_err(&pdev->dev, "Wrong channel configuration\n"); 764 err = -EINVAL; 765 goto err_tasklet_kill; 766 } 767 768 td_chan->chan.device = &td->dma; 769 td_chan->chan.cookie = 1; 770 td_chan->chan.chan_id = i; 771 spin_lock_init(&td_chan->lock); 772 INIT_LIST_HEAD(&td_chan->active_list); 773 INIT_LIST_HEAD(&td_chan->queue); 774 INIT_LIST_HEAD(&td_chan->free_list); 775 776 td_chan->descs = pchan->descriptors; 777 td_chan->desc_elems = pchan->descriptor_elements; 778 td_chan->bytes_per_line = pchan->bytes_per_line; 779 td_chan->direction = pchan->rx ? DMA_FROM_DEVICE : 780 DMA_TO_DEVICE; 781 782 td_chan->membase = td->membase + 783 (i / 2) * TIMBDMA_INSTANCE_OFFSET + 784 (pchan->rx ? 0 : TIMBDMA_INSTANCE_TX_OFFSET); 785 786 dev_dbg(&pdev->dev, "Chan: %d, membase: %p\n", 787 i, td_chan->membase); 788 789 list_add_tail(&td_chan->chan.device_node, &td->dma.channels); 790 } 791 792 err = dma_async_device_register(&td->dma); 793 if (err) { 794 dev_err(&pdev->dev, "Failed to register async device\n"); 795 goto err_free_irq; 796 } 797 798 platform_set_drvdata(pdev, td); 799 800 dev_dbg(&pdev->dev, "Probe result: %d\n", err); 801 return err; 802 803 err_free_irq: 804 free_irq(irq, td); 805 err_tasklet_kill: 806 tasklet_kill(&td->tasklet); 807 iounmap(td->membase); 808 err_free_mem: 809 kfree(td); 810 err_release_region: 811 release_mem_region(iomem->start, resource_size(iomem)); 812 813 return err; 814 815 } 816 817 static int __devexit td_remove(struct platform_device *pdev) 818 { 819 struct timb_dma *td = platform_get_drvdata(pdev); 820 struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 821 int irq = platform_get_irq(pdev, 0); 822 823 dma_async_device_unregister(&td->dma); 824 free_irq(irq, td); 825 tasklet_kill(&td->tasklet); 826 iounmap(td->membase); 827 kfree(td); 828 release_mem_region(iomem->start, resource_size(iomem)); 829 830 platform_set_drvdata(pdev, NULL); 831 832 dev_dbg(&pdev->dev, "Removed...\n"); 833 return 0; 834 } 835 836 static struct platform_driver td_driver = { 837 .driver = { 838 .name = DRIVER_NAME, 839 .owner = THIS_MODULE, 840 }, 841 .probe = td_probe, 842 .remove = __exit_p(td_remove), 843 }; 844 845 static int __init td_init(void) 846 { 847 return platform_driver_register(&td_driver); 848 } 849 module_init(td_init); 850 851 static void __exit td_exit(void) 852 { 853 platform_driver_unregister(&td_driver); 854 } 855 module_exit(td_exit); 856 857 MODULE_LICENSE("GPL v2"); 858 MODULE_DESCRIPTION("Timberdale DMA controller driver"); 859 MODULE_AUTHOR("Pelagicore AB <info@pelagicore.com>"); 860 MODULE_ALIAS("platform:"DRIVER_NAME); 861