1 /* 2 * Core driver for the Synopsys DesignWare DMA Controller 3 * 4 * Copyright (C) 2007-2008 Atmel Corporation 5 * Copyright (C) 2010-2011 ST Microelectronics 6 * Copyright (C) 2013 Intel Corporation 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/bitops.h> 14 #include <linux/delay.h> 15 #include <linux/dmaengine.h> 16 #include <linux/dma-mapping.h> 17 #include <linux/dmapool.h> 18 #include <linux/err.h> 19 #include <linux/init.h> 20 #include <linux/interrupt.h> 21 #include <linux/io.h> 22 #include <linux/mm.h> 23 #include <linux/module.h> 24 #include <linux/slab.h> 25 #include <linux/pm_runtime.h> 26 27 #include "../dmaengine.h" 28 #include "internal.h" 29 30 /* 31 * This supports the Synopsys "DesignWare AHB Central DMA Controller", 32 * (DW_ahb_dmac) which is used with various AMBA 2.0 systems (not all 33 * of which use ARM any more). See the "Databook" from Synopsys for 34 * information beyond what licensees probably provide. 35 * 36 * The driver has been tested with the Atmel AT32AP7000, which does not 37 * support descriptor writeback. 38 */ 39 40 #define DWC_DEFAULT_CTLLO(_chan) ({ \ 41 struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan); \ 42 struct dma_slave_config *_sconfig = &_dwc->dma_sconfig; \ 43 bool _is_slave = is_slave_direction(_dwc->direction); \ 44 u8 _smsize = _is_slave ? _sconfig->src_maxburst : \ 45 DW_DMA_MSIZE_16; \ 46 u8 _dmsize = _is_slave ? _sconfig->dst_maxburst : \ 47 DW_DMA_MSIZE_16; \ 48 u8 _dms = (_dwc->direction == DMA_MEM_TO_DEV) ? \ 49 _dwc->p_master : _dwc->m_master; \ 50 u8 _sms = (_dwc->direction == DMA_DEV_TO_MEM) ? \ 51 _dwc->p_master : _dwc->m_master; \ 52 \ 53 (DWC_CTLL_DST_MSIZE(_dmsize) \ 54 | DWC_CTLL_SRC_MSIZE(_smsize) \ 55 | DWC_CTLL_LLP_D_EN \ 56 | DWC_CTLL_LLP_S_EN \ 57 | DWC_CTLL_DMS(_dms) \ 58 | DWC_CTLL_SMS(_sms)); \ 59 }) 60 61 /* The set of bus widths supported by the DMA controller */ 62 #define DW_DMA_BUSWIDTHS \ 63 BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \ 64 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ 65 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ 66 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) 67 68 /*----------------------------------------------------------------------*/ 69 70 static struct device *chan2dev(struct dma_chan *chan) 71 { 72 return &chan->dev->device; 73 } 74 75 static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc) 76 { 77 return to_dw_desc(dwc->active_list.next); 78 } 79 80 static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx) 81 { 82 struct dw_desc *desc = txd_to_dw_desc(tx); 83 struct dw_dma_chan *dwc = to_dw_dma_chan(tx->chan); 84 dma_cookie_t cookie; 85 unsigned long flags; 86 87 spin_lock_irqsave(&dwc->lock, flags); 88 cookie = dma_cookie_assign(tx); 89 90 /* 91 * REVISIT: We should attempt to chain as many descriptors as 92 * possible, perhaps even appending to those already submitted 93 * for DMA. But this is hard to do in a race-free manner. 94 */ 95 96 list_add_tail(&desc->desc_node, &dwc->queue); 97 spin_unlock_irqrestore(&dwc->lock, flags); 98 dev_vdbg(chan2dev(tx->chan), "%s: queued %u\n", 99 __func__, desc->txd.cookie); 100 101 return cookie; 102 } 103 104 static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc) 105 { 106 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 107 struct dw_desc *desc; 108 dma_addr_t phys; 109 110 desc = dma_pool_zalloc(dw->desc_pool, GFP_ATOMIC, &phys); 111 if (!desc) 112 return NULL; 113 114 dwc->descs_allocated++; 115 INIT_LIST_HEAD(&desc->tx_list); 116 dma_async_tx_descriptor_init(&desc->txd, &dwc->chan); 117 desc->txd.tx_submit = dwc_tx_submit; 118 desc->txd.flags = DMA_CTRL_ACK; 119 desc->txd.phys = phys; 120 return desc; 121 } 122 123 static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc) 124 { 125 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 126 struct dw_desc *child, *_next; 127 128 if (unlikely(!desc)) 129 return; 130 131 list_for_each_entry_safe(child, _next, &desc->tx_list, desc_node) { 132 list_del(&child->desc_node); 133 dma_pool_free(dw->desc_pool, child, child->txd.phys); 134 dwc->descs_allocated--; 135 } 136 137 dma_pool_free(dw->desc_pool, desc, desc->txd.phys); 138 dwc->descs_allocated--; 139 } 140 141 static void dwc_initialize(struct dw_dma_chan *dwc) 142 { 143 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 144 u32 cfghi = DWC_CFGH_FIFO_MODE; 145 u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority); 146 147 if (test_bit(DW_DMA_IS_INITIALIZED, &dwc->flags)) 148 return; 149 150 cfghi |= DWC_CFGH_DST_PER(dwc->dst_id); 151 cfghi |= DWC_CFGH_SRC_PER(dwc->src_id); 152 153 channel_writel(dwc, CFG_LO, cfglo); 154 channel_writel(dwc, CFG_HI, cfghi); 155 156 /* Enable interrupts */ 157 channel_set_bit(dw, MASK.XFER, dwc->mask); 158 channel_set_bit(dw, MASK.ERROR, dwc->mask); 159 160 set_bit(DW_DMA_IS_INITIALIZED, &dwc->flags); 161 } 162 163 /*----------------------------------------------------------------------*/ 164 165 static inline void dwc_dump_chan_regs(struct dw_dma_chan *dwc) 166 { 167 dev_err(chan2dev(&dwc->chan), 168 " SAR: 0x%x DAR: 0x%x LLP: 0x%x CTL: 0x%x:%08x\n", 169 channel_readl(dwc, SAR), 170 channel_readl(dwc, DAR), 171 channel_readl(dwc, LLP), 172 channel_readl(dwc, CTL_HI), 173 channel_readl(dwc, CTL_LO)); 174 } 175 176 static inline void dwc_chan_disable(struct dw_dma *dw, struct dw_dma_chan *dwc) 177 { 178 channel_clear_bit(dw, CH_EN, dwc->mask); 179 while (dma_readl(dw, CH_EN) & dwc->mask) 180 cpu_relax(); 181 } 182 183 /*----------------------------------------------------------------------*/ 184 185 /* Perform single block transfer */ 186 static inline void dwc_do_single_block(struct dw_dma_chan *dwc, 187 struct dw_desc *desc) 188 { 189 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 190 u32 ctllo; 191 192 /* 193 * Software emulation of LLP mode relies on interrupts to continue 194 * multi block transfer. 195 */ 196 ctllo = lli_read(desc, ctllo) | DWC_CTLL_INT_EN; 197 198 channel_writel(dwc, SAR, lli_read(desc, sar)); 199 channel_writel(dwc, DAR, lli_read(desc, dar)); 200 channel_writel(dwc, CTL_LO, ctllo); 201 channel_writel(dwc, CTL_HI, lli_read(desc, ctlhi)); 202 channel_set_bit(dw, CH_EN, dwc->mask); 203 204 /* Move pointer to next descriptor */ 205 dwc->tx_node_active = dwc->tx_node_active->next; 206 } 207 208 /* Called with dwc->lock held and bh disabled */ 209 static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first) 210 { 211 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 212 u8 lms = DWC_LLP_LMS(dwc->m_master); 213 unsigned long was_soft_llp; 214 215 /* ASSERT: channel is idle */ 216 if (dma_readl(dw, CH_EN) & dwc->mask) { 217 dev_err(chan2dev(&dwc->chan), 218 "%s: BUG: Attempted to start non-idle channel\n", 219 __func__); 220 dwc_dump_chan_regs(dwc); 221 222 /* The tasklet will hopefully advance the queue... */ 223 return; 224 } 225 226 if (dwc->nollp) { 227 was_soft_llp = test_and_set_bit(DW_DMA_IS_SOFT_LLP, 228 &dwc->flags); 229 if (was_soft_llp) { 230 dev_err(chan2dev(&dwc->chan), 231 "BUG: Attempted to start new LLP transfer inside ongoing one\n"); 232 return; 233 } 234 235 dwc_initialize(dwc); 236 237 first->residue = first->total_len; 238 dwc->tx_node_active = &first->tx_list; 239 240 /* Submit first block */ 241 dwc_do_single_block(dwc, first); 242 243 return; 244 } 245 246 dwc_initialize(dwc); 247 248 channel_writel(dwc, LLP, first->txd.phys | lms); 249 channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); 250 channel_writel(dwc, CTL_HI, 0); 251 channel_set_bit(dw, CH_EN, dwc->mask); 252 } 253 254 static void dwc_dostart_first_queued(struct dw_dma_chan *dwc) 255 { 256 struct dw_desc *desc; 257 258 if (list_empty(&dwc->queue)) 259 return; 260 261 list_move(dwc->queue.next, &dwc->active_list); 262 desc = dwc_first_active(dwc); 263 dev_vdbg(chan2dev(&dwc->chan), "%s: started %u\n", __func__, desc->txd.cookie); 264 dwc_dostart(dwc, desc); 265 } 266 267 /*----------------------------------------------------------------------*/ 268 269 static void 270 dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc, 271 bool callback_required) 272 { 273 dma_async_tx_callback callback = NULL; 274 void *param = NULL; 275 struct dma_async_tx_descriptor *txd = &desc->txd; 276 struct dw_desc *child; 277 unsigned long flags; 278 279 dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie); 280 281 spin_lock_irqsave(&dwc->lock, flags); 282 dma_cookie_complete(txd); 283 if (callback_required) { 284 callback = txd->callback; 285 param = txd->callback_param; 286 } 287 288 /* async_tx_ack */ 289 list_for_each_entry(child, &desc->tx_list, desc_node) 290 async_tx_ack(&child->txd); 291 async_tx_ack(&desc->txd); 292 dwc_desc_put(dwc, desc); 293 spin_unlock_irqrestore(&dwc->lock, flags); 294 295 if (callback) 296 callback(param); 297 } 298 299 static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc) 300 { 301 struct dw_desc *desc, *_desc; 302 LIST_HEAD(list); 303 unsigned long flags; 304 305 spin_lock_irqsave(&dwc->lock, flags); 306 if (dma_readl(dw, CH_EN) & dwc->mask) { 307 dev_err(chan2dev(&dwc->chan), 308 "BUG: XFER bit set, but channel not idle!\n"); 309 310 /* Try to continue after resetting the channel... */ 311 dwc_chan_disable(dw, dwc); 312 } 313 314 /* 315 * Submit queued descriptors ASAP, i.e. before we go through 316 * the completed ones. 317 */ 318 list_splice_init(&dwc->active_list, &list); 319 dwc_dostart_first_queued(dwc); 320 321 spin_unlock_irqrestore(&dwc->lock, flags); 322 323 list_for_each_entry_safe(desc, _desc, &list, desc_node) 324 dwc_descriptor_complete(dwc, desc, true); 325 } 326 327 /* Returns how many bytes were already received from source */ 328 static inline u32 dwc_get_sent(struct dw_dma_chan *dwc) 329 { 330 u32 ctlhi = channel_readl(dwc, CTL_HI); 331 u32 ctllo = channel_readl(dwc, CTL_LO); 332 333 return (ctlhi & DWC_CTLH_BLOCK_TS_MASK) * (1 << (ctllo >> 4 & 7)); 334 } 335 336 static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc) 337 { 338 dma_addr_t llp; 339 struct dw_desc *desc, *_desc; 340 struct dw_desc *child; 341 u32 status_xfer; 342 unsigned long flags; 343 344 spin_lock_irqsave(&dwc->lock, flags); 345 llp = channel_readl(dwc, LLP); 346 status_xfer = dma_readl(dw, RAW.XFER); 347 348 if (status_xfer & dwc->mask) { 349 /* Everything we've submitted is done */ 350 dma_writel(dw, CLEAR.XFER, dwc->mask); 351 352 if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) { 353 struct list_head *head, *active = dwc->tx_node_active; 354 355 /* 356 * We are inside first active descriptor. 357 * Otherwise something is really wrong. 358 */ 359 desc = dwc_first_active(dwc); 360 361 head = &desc->tx_list; 362 if (active != head) { 363 /* Update residue to reflect last sent descriptor */ 364 if (active == head->next) 365 desc->residue -= desc->len; 366 else 367 desc->residue -= to_dw_desc(active->prev)->len; 368 369 child = to_dw_desc(active); 370 371 /* Submit next block */ 372 dwc_do_single_block(dwc, child); 373 374 spin_unlock_irqrestore(&dwc->lock, flags); 375 return; 376 } 377 378 /* We are done here */ 379 clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags); 380 } 381 382 spin_unlock_irqrestore(&dwc->lock, flags); 383 384 dwc_complete_all(dw, dwc); 385 return; 386 } 387 388 if (list_empty(&dwc->active_list)) { 389 spin_unlock_irqrestore(&dwc->lock, flags); 390 return; 391 } 392 393 if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) { 394 dev_vdbg(chan2dev(&dwc->chan), "%s: soft LLP mode\n", __func__); 395 spin_unlock_irqrestore(&dwc->lock, flags); 396 return; 397 } 398 399 dev_vdbg(chan2dev(&dwc->chan), "%s: llp=%pad\n", __func__, &llp); 400 401 list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) { 402 /* Initial residue value */ 403 desc->residue = desc->total_len; 404 405 /* Check first descriptors addr */ 406 if (desc->txd.phys == DWC_LLP_LOC(llp)) { 407 spin_unlock_irqrestore(&dwc->lock, flags); 408 return; 409 } 410 411 /* Check first descriptors llp */ 412 if (lli_read(desc, llp) == llp) { 413 /* This one is currently in progress */ 414 desc->residue -= dwc_get_sent(dwc); 415 spin_unlock_irqrestore(&dwc->lock, flags); 416 return; 417 } 418 419 desc->residue -= desc->len; 420 list_for_each_entry(child, &desc->tx_list, desc_node) { 421 if (lli_read(child, llp) == llp) { 422 /* Currently in progress */ 423 desc->residue -= dwc_get_sent(dwc); 424 spin_unlock_irqrestore(&dwc->lock, flags); 425 return; 426 } 427 desc->residue -= child->len; 428 } 429 430 /* 431 * No descriptors so far seem to be in progress, i.e. 432 * this one must be done. 433 */ 434 spin_unlock_irqrestore(&dwc->lock, flags); 435 dwc_descriptor_complete(dwc, desc, true); 436 spin_lock_irqsave(&dwc->lock, flags); 437 } 438 439 dev_err(chan2dev(&dwc->chan), 440 "BUG: All descriptors done, but channel not idle!\n"); 441 442 /* Try to continue after resetting the channel... */ 443 dwc_chan_disable(dw, dwc); 444 445 dwc_dostart_first_queued(dwc); 446 spin_unlock_irqrestore(&dwc->lock, flags); 447 } 448 449 static inline void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_desc *desc) 450 { 451 dev_crit(chan2dev(&dwc->chan), " desc: s0x%x d0x%x l0x%x c0x%x:%x\n", 452 lli_read(desc, sar), 453 lli_read(desc, dar), 454 lli_read(desc, llp), 455 lli_read(desc, ctlhi), 456 lli_read(desc, ctllo)); 457 } 458 459 static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc) 460 { 461 struct dw_desc *bad_desc; 462 struct dw_desc *child; 463 unsigned long flags; 464 465 dwc_scan_descriptors(dw, dwc); 466 467 spin_lock_irqsave(&dwc->lock, flags); 468 469 /* 470 * The descriptor currently at the head of the active list is 471 * borked. Since we don't have any way to report errors, we'll 472 * just have to scream loudly and try to carry on. 473 */ 474 bad_desc = dwc_first_active(dwc); 475 list_del_init(&bad_desc->desc_node); 476 list_move(dwc->queue.next, dwc->active_list.prev); 477 478 /* Clear the error flag and try to restart the controller */ 479 dma_writel(dw, CLEAR.ERROR, dwc->mask); 480 if (!list_empty(&dwc->active_list)) 481 dwc_dostart(dwc, dwc_first_active(dwc)); 482 483 /* 484 * WARN may seem harsh, but since this only happens 485 * when someone submits a bad physical address in a 486 * descriptor, we should consider ourselves lucky that the 487 * controller flagged an error instead of scribbling over 488 * random memory locations. 489 */ 490 dev_WARN(chan2dev(&dwc->chan), "Bad descriptor submitted for DMA!\n" 491 " cookie: %d\n", bad_desc->txd.cookie); 492 dwc_dump_lli(dwc, bad_desc); 493 list_for_each_entry(child, &bad_desc->tx_list, desc_node) 494 dwc_dump_lli(dwc, child); 495 496 spin_unlock_irqrestore(&dwc->lock, flags); 497 498 /* Pretend the descriptor completed successfully */ 499 dwc_descriptor_complete(dwc, bad_desc, true); 500 } 501 502 /* --------------------- Cyclic DMA API extensions -------------------- */ 503 504 dma_addr_t dw_dma_get_src_addr(struct dma_chan *chan) 505 { 506 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 507 return channel_readl(dwc, SAR); 508 } 509 EXPORT_SYMBOL(dw_dma_get_src_addr); 510 511 dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan) 512 { 513 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 514 return channel_readl(dwc, DAR); 515 } 516 EXPORT_SYMBOL(dw_dma_get_dst_addr); 517 518 /* Called with dwc->lock held and all DMAC interrupts disabled */ 519 static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc, 520 u32 status_block, u32 status_err, u32 status_xfer) 521 { 522 unsigned long flags; 523 524 if (status_block & dwc->mask) { 525 void (*callback)(void *param); 526 void *callback_param; 527 528 dev_vdbg(chan2dev(&dwc->chan), "new cyclic period llp 0x%08x\n", 529 channel_readl(dwc, LLP)); 530 dma_writel(dw, CLEAR.BLOCK, dwc->mask); 531 532 callback = dwc->cdesc->period_callback; 533 callback_param = dwc->cdesc->period_callback_param; 534 535 if (callback) 536 callback(callback_param); 537 } 538 539 /* 540 * Error and transfer complete are highly unlikely, and will most 541 * likely be due to a configuration error by the user. 542 */ 543 if (unlikely(status_err & dwc->mask) || 544 unlikely(status_xfer & dwc->mask)) { 545 unsigned int i; 546 547 dev_err(chan2dev(&dwc->chan), 548 "cyclic DMA unexpected %s interrupt, stopping DMA transfer\n", 549 status_xfer ? "xfer" : "error"); 550 551 spin_lock_irqsave(&dwc->lock, flags); 552 553 dwc_dump_chan_regs(dwc); 554 555 dwc_chan_disable(dw, dwc); 556 557 /* Make sure DMA does not restart by loading a new list */ 558 channel_writel(dwc, LLP, 0); 559 channel_writel(dwc, CTL_LO, 0); 560 channel_writel(dwc, CTL_HI, 0); 561 562 dma_writel(dw, CLEAR.BLOCK, dwc->mask); 563 dma_writel(dw, CLEAR.ERROR, dwc->mask); 564 dma_writel(dw, CLEAR.XFER, dwc->mask); 565 566 for (i = 0; i < dwc->cdesc->periods; i++) 567 dwc_dump_lli(dwc, dwc->cdesc->desc[i]); 568 569 spin_unlock_irqrestore(&dwc->lock, flags); 570 } 571 572 /* Re-enable interrupts */ 573 channel_set_bit(dw, MASK.BLOCK, dwc->mask); 574 } 575 576 /* ------------------------------------------------------------------------- */ 577 578 static void dw_dma_tasklet(unsigned long data) 579 { 580 struct dw_dma *dw = (struct dw_dma *)data; 581 struct dw_dma_chan *dwc; 582 u32 status_block; 583 u32 status_xfer; 584 u32 status_err; 585 unsigned int i; 586 587 status_block = dma_readl(dw, RAW.BLOCK); 588 status_xfer = dma_readl(dw, RAW.XFER); 589 status_err = dma_readl(dw, RAW.ERROR); 590 591 dev_vdbg(dw->dma.dev, "%s: status_err=%x\n", __func__, status_err); 592 593 for (i = 0; i < dw->dma.chancnt; i++) { 594 dwc = &dw->chan[i]; 595 if (test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) 596 dwc_handle_cyclic(dw, dwc, status_block, status_err, 597 status_xfer); 598 else if (status_err & (1 << i)) 599 dwc_handle_error(dw, dwc); 600 else if (status_xfer & (1 << i)) 601 dwc_scan_descriptors(dw, dwc); 602 } 603 604 /* Re-enable interrupts */ 605 channel_set_bit(dw, MASK.XFER, dw->all_chan_mask); 606 channel_set_bit(dw, MASK.ERROR, dw->all_chan_mask); 607 } 608 609 static irqreturn_t dw_dma_interrupt(int irq, void *dev_id) 610 { 611 struct dw_dma *dw = dev_id; 612 u32 status; 613 614 /* Check if we have any interrupt from the DMAC which is not in use */ 615 if (!dw->in_use) 616 return IRQ_NONE; 617 618 status = dma_readl(dw, STATUS_INT); 619 dev_vdbg(dw->dma.dev, "%s: status=0x%x\n", __func__, status); 620 621 /* Check if we have any interrupt from the DMAC */ 622 if (!status) 623 return IRQ_NONE; 624 625 /* 626 * Just disable the interrupts. We'll turn them back on in the 627 * softirq handler. 628 */ 629 channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask); 630 channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask); 631 channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask); 632 633 status = dma_readl(dw, STATUS_INT); 634 if (status) { 635 dev_err(dw->dma.dev, 636 "BUG: Unexpected interrupts pending: 0x%x\n", 637 status); 638 639 /* Try to recover */ 640 channel_clear_bit(dw, MASK.XFER, (1 << 8) - 1); 641 channel_clear_bit(dw, MASK.BLOCK, (1 << 8) - 1); 642 channel_clear_bit(dw, MASK.SRC_TRAN, (1 << 8) - 1); 643 channel_clear_bit(dw, MASK.DST_TRAN, (1 << 8) - 1); 644 channel_clear_bit(dw, MASK.ERROR, (1 << 8) - 1); 645 } 646 647 tasklet_schedule(&dw->tasklet); 648 649 return IRQ_HANDLED; 650 } 651 652 /*----------------------------------------------------------------------*/ 653 654 static struct dma_async_tx_descriptor * 655 dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, 656 size_t len, unsigned long flags) 657 { 658 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 659 struct dw_dma *dw = to_dw_dma(chan->device); 660 struct dw_desc *desc; 661 struct dw_desc *first; 662 struct dw_desc *prev; 663 size_t xfer_count; 664 size_t offset; 665 u8 m_master = dwc->m_master; 666 unsigned int src_width; 667 unsigned int dst_width; 668 unsigned int data_width = dw->pdata->data_width[m_master]; 669 u32 ctllo; 670 u8 lms = DWC_LLP_LMS(m_master); 671 672 dev_vdbg(chan2dev(chan), 673 "%s: d%pad s%pad l0x%zx f0x%lx\n", __func__, 674 &dest, &src, len, flags); 675 676 if (unlikely(!len)) { 677 dev_dbg(chan2dev(chan), "%s: length is zero!\n", __func__); 678 return NULL; 679 } 680 681 dwc->direction = DMA_MEM_TO_MEM; 682 683 src_width = dst_width = __ffs(data_width | src | dest | len); 684 685 ctllo = DWC_DEFAULT_CTLLO(chan) 686 | DWC_CTLL_DST_WIDTH(dst_width) 687 | DWC_CTLL_SRC_WIDTH(src_width) 688 | DWC_CTLL_DST_INC 689 | DWC_CTLL_SRC_INC 690 | DWC_CTLL_FC_M2M; 691 prev = first = NULL; 692 693 for (offset = 0; offset < len; offset += xfer_count << src_width) { 694 xfer_count = min_t(size_t, (len - offset) >> src_width, 695 dwc->block_size); 696 697 desc = dwc_desc_get(dwc); 698 if (!desc) 699 goto err_desc_get; 700 701 lli_write(desc, sar, src + offset); 702 lli_write(desc, dar, dest + offset); 703 lli_write(desc, ctllo, ctllo); 704 lli_write(desc, ctlhi, xfer_count); 705 desc->len = xfer_count << src_width; 706 707 if (!first) { 708 first = desc; 709 } else { 710 lli_write(prev, llp, desc->txd.phys | lms); 711 list_add_tail(&desc->desc_node, &first->tx_list); 712 } 713 prev = desc; 714 } 715 716 if (flags & DMA_PREP_INTERRUPT) 717 /* Trigger interrupt after last block */ 718 lli_set(prev, ctllo, DWC_CTLL_INT_EN); 719 720 prev->lli.llp = 0; 721 lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); 722 first->txd.flags = flags; 723 first->total_len = len; 724 725 return &first->txd; 726 727 err_desc_get: 728 dwc_desc_put(dwc, first); 729 return NULL; 730 } 731 732 static struct dma_async_tx_descriptor * 733 dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, 734 unsigned int sg_len, enum dma_transfer_direction direction, 735 unsigned long flags, void *context) 736 { 737 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 738 struct dw_dma *dw = to_dw_dma(chan->device); 739 struct dma_slave_config *sconfig = &dwc->dma_sconfig; 740 struct dw_desc *prev; 741 struct dw_desc *first; 742 u32 ctllo; 743 u8 m_master = dwc->m_master; 744 u8 lms = DWC_LLP_LMS(m_master); 745 dma_addr_t reg; 746 unsigned int reg_width; 747 unsigned int mem_width; 748 unsigned int data_width = dw->pdata->data_width[m_master]; 749 unsigned int i; 750 struct scatterlist *sg; 751 size_t total_len = 0; 752 753 dev_vdbg(chan2dev(chan), "%s\n", __func__); 754 755 if (unlikely(!is_slave_direction(direction) || !sg_len)) 756 return NULL; 757 758 dwc->direction = direction; 759 760 prev = first = NULL; 761 762 switch (direction) { 763 case DMA_MEM_TO_DEV: 764 reg_width = __ffs(sconfig->dst_addr_width); 765 reg = sconfig->dst_addr; 766 ctllo = (DWC_DEFAULT_CTLLO(chan) 767 | DWC_CTLL_DST_WIDTH(reg_width) 768 | DWC_CTLL_DST_FIX 769 | DWC_CTLL_SRC_INC); 770 771 ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) : 772 DWC_CTLL_FC(DW_DMA_FC_D_M2P); 773 774 for_each_sg(sgl, sg, sg_len, i) { 775 struct dw_desc *desc; 776 u32 len, dlen, mem; 777 778 mem = sg_dma_address(sg); 779 len = sg_dma_len(sg); 780 781 mem_width = __ffs(data_width | mem | len); 782 783 slave_sg_todev_fill_desc: 784 desc = dwc_desc_get(dwc); 785 if (!desc) 786 goto err_desc_get; 787 788 lli_write(desc, sar, mem); 789 lli_write(desc, dar, reg); 790 lli_write(desc, ctllo, ctllo | DWC_CTLL_SRC_WIDTH(mem_width)); 791 if ((len >> mem_width) > dwc->block_size) { 792 dlen = dwc->block_size << mem_width; 793 mem += dlen; 794 len -= dlen; 795 } else { 796 dlen = len; 797 len = 0; 798 } 799 800 lli_write(desc, ctlhi, dlen >> mem_width); 801 desc->len = dlen; 802 803 if (!first) { 804 first = desc; 805 } else { 806 lli_write(prev, llp, desc->txd.phys | lms); 807 list_add_tail(&desc->desc_node, &first->tx_list); 808 } 809 prev = desc; 810 total_len += dlen; 811 812 if (len) 813 goto slave_sg_todev_fill_desc; 814 } 815 break; 816 case DMA_DEV_TO_MEM: 817 reg_width = __ffs(sconfig->src_addr_width); 818 reg = sconfig->src_addr; 819 ctllo = (DWC_DEFAULT_CTLLO(chan) 820 | DWC_CTLL_SRC_WIDTH(reg_width) 821 | DWC_CTLL_DST_INC 822 | DWC_CTLL_SRC_FIX); 823 824 ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) : 825 DWC_CTLL_FC(DW_DMA_FC_D_P2M); 826 827 for_each_sg(sgl, sg, sg_len, i) { 828 struct dw_desc *desc; 829 u32 len, dlen, mem; 830 831 mem = sg_dma_address(sg); 832 len = sg_dma_len(sg); 833 834 mem_width = __ffs(data_width | mem | len); 835 836 slave_sg_fromdev_fill_desc: 837 desc = dwc_desc_get(dwc); 838 if (!desc) 839 goto err_desc_get; 840 841 lli_write(desc, sar, reg); 842 lli_write(desc, dar, mem); 843 lli_write(desc, ctllo, ctllo | DWC_CTLL_DST_WIDTH(mem_width)); 844 if ((len >> reg_width) > dwc->block_size) { 845 dlen = dwc->block_size << reg_width; 846 mem += dlen; 847 len -= dlen; 848 } else { 849 dlen = len; 850 len = 0; 851 } 852 lli_write(desc, ctlhi, dlen >> reg_width); 853 desc->len = dlen; 854 855 if (!first) { 856 first = desc; 857 } else { 858 lli_write(prev, llp, desc->txd.phys | lms); 859 list_add_tail(&desc->desc_node, &first->tx_list); 860 } 861 prev = desc; 862 total_len += dlen; 863 864 if (len) 865 goto slave_sg_fromdev_fill_desc; 866 } 867 break; 868 default: 869 return NULL; 870 } 871 872 if (flags & DMA_PREP_INTERRUPT) 873 /* Trigger interrupt after last block */ 874 lli_set(prev, ctllo, DWC_CTLL_INT_EN); 875 876 prev->lli.llp = 0; 877 lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); 878 first->total_len = total_len; 879 880 return &first->txd; 881 882 err_desc_get: 883 dev_err(chan2dev(chan), 884 "not enough descriptors available. Direction %d\n", direction); 885 dwc_desc_put(dwc, first); 886 return NULL; 887 } 888 889 bool dw_dma_filter(struct dma_chan *chan, void *param) 890 { 891 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 892 struct dw_dma_slave *dws = param; 893 894 if (dws->dma_dev != chan->device->dev) 895 return false; 896 897 /* We have to copy data since dws can be temporary storage */ 898 899 dwc->src_id = dws->src_id; 900 dwc->dst_id = dws->dst_id; 901 902 dwc->m_master = dws->m_master; 903 dwc->p_master = dws->p_master; 904 905 return true; 906 } 907 EXPORT_SYMBOL_GPL(dw_dma_filter); 908 909 /* 910 * Fix sconfig's burst size according to dw_dmac. We need to convert them as: 911 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3. 912 * 913 * NOTE: burst size 2 is not supported by controller. 914 * 915 * This can be done by finding least significant bit set: n & (n - 1) 916 */ 917 static inline void convert_burst(u32 *maxburst) 918 { 919 if (*maxburst > 1) 920 *maxburst = fls(*maxburst) - 2; 921 else 922 *maxburst = 0; 923 } 924 925 static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig) 926 { 927 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 928 929 /* Check if chan will be configured for slave transfers */ 930 if (!is_slave_direction(sconfig->direction)) 931 return -EINVAL; 932 933 memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig)); 934 dwc->direction = sconfig->direction; 935 936 convert_burst(&dwc->dma_sconfig.src_maxburst); 937 convert_burst(&dwc->dma_sconfig.dst_maxburst); 938 939 return 0; 940 } 941 942 static int dwc_pause(struct dma_chan *chan) 943 { 944 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 945 unsigned long flags; 946 unsigned int count = 20; /* timeout iterations */ 947 u32 cfglo; 948 949 spin_lock_irqsave(&dwc->lock, flags); 950 951 cfglo = channel_readl(dwc, CFG_LO); 952 channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP); 953 while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--) 954 udelay(2); 955 956 set_bit(DW_DMA_IS_PAUSED, &dwc->flags); 957 958 spin_unlock_irqrestore(&dwc->lock, flags); 959 960 return 0; 961 } 962 963 static inline void dwc_chan_resume(struct dw_dma_chan *dwc) 964 { 965 u32 cfglo = channel_readl(dwc, CFG_LO); 966 967 channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP); 968 969 clear_bit(DW_DMA_IS_PAUSED, &dwc->flags); 970 } 971 972 static int dwc_resume(struct dma_chan *chan) 973 { 974 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 975 unsigned long flags; 976 977 spin_lock_irqsave(&dwc->lock, flags); 978 979 if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags)) 980 dwc_chan_resume(dwc); 981 982 spin_unlock_irqrestore(&dwc->lock, flags); 983 984 return 0; 985 } 986 987 static int dwc_terminate_all(struct dma_chan *chan) 988 { 989 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 990 struct dw_dma *dw = to_dw_dma(chan->device); 991 struct dw_desc *desc, *_desc; 992 unsigned long flags; 993 LIST_HEAD(list); 994 995 spin_lock_irqsave(&dwc->lock, flags); 996 997 clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags); 998 999 dwc_chan_disable(dw, dwc); 1000 1001 dwc_chan_resume(dwc); 1002 1003 /* active_list entries will end up before queued entries */ 1004 list_splice_init(&dwc->queue, &list); 1005 list_splice_init(&dwc->active_list, &list); 1006 1007 spin_unlock_irqrestore(&dwc->lock, flags); 1008 1009 /* Flush all pending and queued descriptors */ 1010 list_for_each_entry_safe(desc, _desc, &list, desc_node) 1011 dwc_descriptor_complete(dwc, desc, false); 1012 1013 return 0; 1014 } 1015 1016 static struct dw_desc *dwc_find_desc(struct dw_dma_chan *dwc, dma_cookie_t c) 1017 { 1018 struct dw_desc *desc; 1019 1020 list_for_each_entry(desc, &dwc->active_list, desc_node) 1021 if (desc->txd.cookie == c) 1022 return desc; 1023 1024 return NULL; 1025 } 1026 1027 static u32 dwc_get_residue(struct dw_dma_chan *dwc, dma_cookie_t cookie) 1028 { 1029 struct dw_desc *desc; 1030 unsigned long flags; 1031 u32 residue; 1032 1033 spin_lock_irqsave(&dwc->lock, flags); 1034 1035 desc = dwc_find_desc(dwc, cookie); 1036 if (desc) { 1037 if (desc == dwc_first_active(dwc)) { 1038 residue = desc->residue; 1039 if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags) && residue) 1040 residue -= dwc_get_sent(dwc); 1041 } else { 1042 residue = desc->total_len; 1043 } 1044 } else { 1045 residue = 0; 1046 } 1047 1048 spin_unlock_irqrestore(&dwc->lock, flags); 1049 return residue; 1050 } 1051 1052 static enum dma_status 1053 dwc_tx_status(struct dma_chan *chan, 1054 dma_cookie_t cookie, 1055 struct dma_tx_state *txstate) 1056 { 1057 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1058 enum dma_status ret; 1059 1060 ret = dma_cookie_status(chan, cookie, txstate); 1061 if (ret == DMA_COMPLETE) 1062 return ret; 1063 1064 dwc_scan_descriptors(to_dw_dma(chan->device), dwc); 1065 1066 ret = dma_cookie_status(chan, cookie, txstate); 1067 if (ret == DMA_COMPLETE) 1068 return ret; 1069 1070 dma_set_residue(txstate, dwc_get_residue(dwc, cookie)); 1071 1072 if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags) && ret == DMA_IN_PROGRESS) 1073 return DMA_PAUSED; 1074 1075 return ret; 1076 } 1077 1078 static void dwc_issue_pending(struct dma_chan *chan) 1079 { 1080 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1081 unsigned long flags; 1082 1083 spin_lock_irqsave(&dwc->lock, flags); 1084 if (list_empty(&dwc->active_list)) 1085 dwc_dostart_first_queued(dwc); 1086 spin_unlock_irqrestore(&dwc->lock, flags); 1087 } 1088 1089 /*----------------------------------------------------------------------*/ 1090 1091 static void dw_dma_off(struct dw_dma *dw) 1092 { 1093 unsigned int i; 1094 1095 dma_writel(dw, CFG, 0); 1096 1097 channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask); 1098 channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask); 1099 channel_clear_bit(dw, MASK.SRC_TRAN, dw->all_chan_mask); 1100 channel_clear_bit(dw, MASK.DST_TRAN, dw->all_chan_mask); 1101 channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask); 1102 1103 while (dma_readl(dw, CFG) & DW_CFG_DMA_EN) 1104 cpu_relax(); 1105 1106 for (i = 0; i < dw->dma.chancnt; i++) 1107 clear_bit(DW_DMA_IS_INITIALIZED, &dw->chan[i].flags); 1108 } 1109 1110 static void dw_dma_on(struct dw_dma *dw) 1111 { 1112 dma_writel(dw, CFG, DW_CFG_DMA_EN); 1113 } 1114 1115 static int dwc_alloc_chan_resources(struct dma_chan *chan) 1116 { 1117 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1118 struct dw_dma *dw = to_dw_dma(chan->device); 1119 1120 dev_vdbg(chan2dev(chan), "%s\n", __func__); 1121 1122 /* ASSERT: channel is idle */ 1123 if (dma_readl(dw, CH_EN) & dwc->mask) { 1124 dev_dbg(chan2dev(chan), "DMA channel not idle?\n"); 1125 return -EIO; 1126 } 1127 1128 dma_cookie_init(chan); 1129 1130 /* 1131 * NOTE: some controllers may have additional features that we 1132 * need to initialize here, like "scatter-gather" (which 1133 * doesn't mean what you think it means), and status writeback. 1134 */ 1135 1136 /* 1137 * We need controller-specific data to set up slave transfers. 1138 */ 1139 if (chan->private && !dw_dma_filter(chan, chan->private)) { 1140 dev_warn(chan2dev(chan), "Wrong controller-specific data\n"); 1141 return -EINVAL; 1142 } 1143 1144 /* Enable controller here if needed */ 1145 if (!dw->in_use) 1146 dw_dma_on(dw); 1147 dw->in_use |= dwc->mask; 1148 1149 return 0; 1150 } 1151 1152 static void dwc_free_chan_resources(struct dma_chan *chan) 1153 { 1154 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1155 struct dw_dma *dw = to_dw_dma(chan->device); 1156 unsigned long flags; 1157 LIST_HEAD(list); 1158 1159 dev_dbg(chan2dev(chan), "%s: descs allocated=%u\n", __func__, 1160 dwc->descs_allocated); 1161 1162 /* ASSERT: channel is idle */ 1163 BUG_ON(!list_empty(&dwc->active_list)); 1164 BUG_ON(!list_empty(&dwc->queue)); 1165 BUG_ON(dma_readl(to_dw_dma(chan->device), CH_EN) & dwc->mask); 1166 1167 spin_lock_irqsave(&dwc->lock, flags); 1168 1169 /* Clear custom channel configuration */ 1170 dwc->src_id = 0; 1171 dwc->dst_id = 0; 1172 1173 dwc->m_master = 0; 1174 dwc->p_master = 0; 1175 1176 clear_bit(DW_DMA_IS_INITIALIZED, &dwc->flags); 1177 1178 /* Disable interrupts */ 1179 channel_clear_bit(dw, MASK.XFER, dwc->mask); 1180 channel_clear_bit(dw, MASK.BLOCK, dwc->mask); 1181 channel_clear_bit(dw, MASK.ERROR, dwc->mask); 1182 1183 spin_unlock_irqrestore(&dwc->lock, flags); 1184 1185 /* Disable controller in case it was a last user */ 1186 dw->in_use &= ~dwc->mask; 1187 if (!dw->in_use) 1188 dw_dma_off(dw); 1189 1190 dev_vdbg(chan2dev(chan), "%s: done\n", __func__); 1191 } 1192 1193 /* --------------------- Cyclic DMA API extensions -------------------- */ 1194 1195 /** 1196 * dw_dma_cyclic_start - start the cyclic DMA transfer 1197 * @chan: the DMA channel to start 1198 * 1199 * Must be called with soft interrupts disabled. Returns zero on success or 1200 * -errno on failure. 1201 */ 1202 int dw_dma_cyclic_start(struct dma_chan *chan) 1203 { 1204 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1205 struct dw_dma *dw = to_dw_dma(chan->device); 1206 unsigned long flags; 1207 1208 if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) { 1209 dev_err(chan2dev(&dwc->chan), "missing prep for cyclic DMA\n"); 1210 return -ENODEV; 1211 } 1212 1213 spin_lock_irqsave(&dwc->lock, flags); 1214 1215 /* Enable interrupts to perform cyclic transfer */ 1216 channel_set_bit(dw, MASK.BLOCK, dwc->mask); 1217 1218 dwc_dostart(dwc, dwc->cdesc->desc[0]); 1219 1220 spin_unlock_irqrestore(&dwc->lock, flags); 1221 1222 return 0; 1223 } 1224 EXPORT_SYMBOL(dw_dma_cyclic_start); 1225 1226 /** 1227 * dw_dma_cyclic_stop - stop the cyclic DMA transfer 1228 * @chan: the DMA channel to stop 1229 * 1230 * Must be called with soft interrupts disabled. 1231 */ 1232 void dw_dma_cyclic_stop(struct dma_chan *chan) 1233 { 1234 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1235 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 1236 unsigned long flags; 1237 1238 spin_lock_irqsave(&dwc->lock, flags); 1239 1240 dwc_chan_disable(dw, dwc); 1241 1242 spin_unlock_irqrestore(&dwc->lock, flags); 1243 } 1244 EXPORT_SYMBOL(dw_dma_cyclic_stop); 1245 1246 /** 1247 * dw_dma_cyclic_prep - prepare the cyclic DMA transfer 1248 * @chan: the DMA channel to prepare 1249 * @buf_addr: physical DMA address where the buffer starts 1250 * @buf_len: total number of bytes for the entire buffer 1251 * @period_len: number of bytes for each period 1252 * @direction: transfer direction, to or from device 1253 * 1254 * Must be called before trying to start the transfer. Returns a valid struct 1255 * dw_cyclic_desc if successful or an ERR_PTR(-errno) if not successful. 1256 */ 1257 struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan, 1258 dma_addr_t buf_addr, size_t buf_len, size_t period_len, 1259 enum dma_transfer_direction direction) 1260 { 1261 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1262 struct dma_slave_config *sconfig = &dwc->dma_sconfig; 1263 struct dw_cyclic_desc *cdesc; 1264 struct dw_cyclic_desc *retval = NULL; 1265 struct dw_desc *desc; 1266 struct dw_desc *last = NULL; 1267 u8 lms = DWC_LLP_LMS(dwc->m_master); 1268 unsigned long was_cyclic; 1269 unsigned int reg_width; 1270 unsigned int periods; 1271 unsigned int i; 1272 unsigned long flags; 1273 1274 spin_lock_irqsave(&dwc->lock, flags); 1275 if (dwc->nollp) { 1276 spin_unlock_irqrestore(&dwc->lock, flags); 1277 dev_dbg(chan2dev(&dwc->chan), 1278 "channel doesn't support LLP transfers\n"); 1279 return ERR_PTR(-EINVAL); 1280 } 1281 1282 if (!list_empty(&dwc->queue) || !list_empty(&dwc->active_list)) { 1283 spin_unlock_irqrestore(&dwc->lock, flags); 1284 dev_dbg(chan2dev(&dwc->chan), 1285 "queue and/or active list are not empty\n"); 1286 return ERR_PTR(-EBUSY); 1287 } 1288 1289 was_cyclic = test_and_set_bit(DW_DMA_IS_CYCLIC, &dwc->flags); 1290 spin_unlock_irqrestore(&dwc->lock, flags); 1291 if (was_cyclic) { 1292 dev_dbg(chan2dev(&dwc->chan), 1293 "channel already prepared for cyclic DMA\n"); 1294 return ERR_PTR(-EBUSY); 1295 } 1296 1297 retval = ERR_PTR(-EINVAL); 1298 1299 if (unlikely(!is_slave_direction(direction))) 1300 goto out_err; 1301 1302 dwc->direction = direction; 1303 1304 if (direction == DMA_MEM_TO_DEV) 1305 reg_width = __ffs(sconfig->dst_addr_width); 1306 else 1307 reg_width = __ffs(sconfig->src_addr_width); 1308 1309 periods = buf_len / period_len; 1310 1311 /* Check for too big/unaligned periods and unaligned DMA buffer. */ 1312 if (period_len > (dwc->block_size << reg_width)) 1313 goto out_err; 1314 if (unlikely(period_len & ((1 << reg_width) - 1))) 1315 goto out_err; 1316 if (unlikely(buf_addr & ((1 << reg_width) - 1))) 1317 goto out_err; 1318 1319 retval = ERR_PTR(-ENOMEM); 1320 1321 cdesc = kzalloc(sizeof(struct dw_cyclic_desc), GFP_KERNEL); 1322 if (!cdesc) 1323 goto out_err; 1324 1325 cdesc->desc = kzalloc(sizeof(struct dw_desc *) * periods, GFP_KERNEL); 1326 if (!cdesc->desc) 1327 goto out_err_alloc; 1328 1329 for (i = 0; i < periods; i++) { 1330 desc = dwc_desc_get(dwc); 1331 if (!desc) 1332 goto out_err_desc_get; 1333 1334 switch (direction) { 1335 case DMA_MEM_TO_DEV: 1336 lli_write(desc, dar, sconfig->dst_addr); 1337 lli_write(desc, sar, buf_addr + period_len * i); 1338 lli_write(desc, ctllo, (DWC_DEFAULT_CTLLO(chan) 1339 | DWC_CTLL_DST_WIDTH(reg_width) 1340 | DWC_CTLL_SRC_WIDTH(reg_width) 1341 | DWC_CTLL_DST_FIX 1342 | DWC_CTLL_SRC_INC 1343 | DWC_CTLL_INT_EN)); 1344 1345 lli_set(desc, ctllo, sconfig->device_fc ? 1346 DWC_CTLL_FC(DW_DMA_FC_P_M2P) : 1347 DWC_CTLL_FC(DW_DMA_FC_D_M2P)); 1348 1349 break; 1350 case DMA_DEV_TO_MEM: 1351 lli_write(desc, dar, buf_addr + period_len * i); 1352 lli_write(desc, sar, sconfig->src_addr); 1353 lli_write(desc, ctllo, (DWC_DEFAULT_CTLLO(chan) 1354 | DWC_CTLL_SRC_WIDTH(reg_width) 1355 | DWC_CTLL_DST_WIDTH(reg_width) 1356 | DWC_CTLL_DST_INC 1357 | DWC_CTLL_SRC_FIX 1358 | DWC_CTLL_INT_EN)); 1359 1360 lli_set(desc, ctllo, sconfig->device_fc ? 1361 DWC_CTLL_FC(DW_DMA_FC_P_P2M) : 1362 DWC_CTLL_FC(DW_DMA_FC_D_P2M)); 1363 1364 break; 1365 default: 1366 break; 1367 } 1368 1369 lli_write(desc, ctlhi, period_len >> reg_width); 1370 cdesc->desc[i] = desc; 1371 1372 if (last) 1373 lli_write(last, llp, desc->txd.phys | lms); 1374 1375 last = desc; 1376 } 1377 1378 /* Let's make a cyclic list */ 1379 lli_write(last, llp, cdesc->desc[0]->txd.phys | lms); 1380 1381 dev_dbg(chan2dev(&dwc->chan), 1382 "cyclic prepared buf %pad len %zu period %zu periods %d\n", 1383 &buf_addr, buf_len, period_len, periods); 1384 1385 cdesc->periods = periods; 1386 dwc->cdesc = cdesc; 1387 1388 return cdesc; 1389 1390 out_err_desc_get: 1391 while (i--) 1392 dwc_desc_put(dwc, cdesc->desc[i]); 1393 out_err_alloc: 1394 kfree(cdesc); 1395 out_err: 1396 clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags); 1397 return (struct dw_cyclic_desc *)retval; 1398 } 1399 EXPORT_SYMBOL(dw_dma_cyclic_prep); 1400 1401 /** 1402 * dw_dma_cyclic_free - free a prepared cyclic DMA transfer 1403 * @chan: the DMA channel to free 1404 */ 1405 void dw_dma_cyclic_free(struct dma_chan *chan) 1406 { 1407 struct dw_dma_chan *dwc = to_dw_dma_chan(chan); 1408 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 1409 struct dw_cyclic_desc *cdesc = dwc->cdesc; 1410 unsigned int i; 1411 unsigned long flags; 1412 1413 dev_dbg(chan2dev(&dwc->chan), "%s\n", __func__); 1414 1415 if (!cdesc) 1416 return; 1417 1418 spin_lock_irqsave(&dwc->lock, flags); 1419 1420 dwc_chan_disable(dw, dwc); 1421 1422 dma_writel(dw, CLEAR.BLOCK, dwc->mask); 1423 dma_writel(dw, CLEAR.ERROR, dwc->mask); 1424 dma_writel(dw, CLEAR.XFER, dwc->mask); 1425 1426 spin_unlock_irqrestore(&dwc->lock, flags); 1427 1428 for (i = 0; i < cdesc->periods; i++) 1429 dwc_desc_put(dwc, cdesc->desc[i]); 1430 1431 kfree(cdesc->desc); 1432 kfree(cdesc); 1433 1434 dwc->cdesc = NULL; 1435 1436 clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags); 1437 } 1438 EXPORT_SYMBOL(dw_dma_cyclic_free); 1439 1440 /*----------------------------------------------------------------------*/ 1441 1442 int dw_dma_probe(struct dw_dma_chip *chip) 1443 { 1444 struct dw_dma_platform_data *pdata; 1445 struct dw_dma *dw; 1446 bool autocfg = false; 1447 unsigned int dw_params; 1448 unsigned int i; 1449 int err; 1450 1451 dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL); 1452 if (!dw) 1453 return -ENOMEM; 1454 1455 dw->pdata = devm_kzalloc(chip->dev, sizeof(*dw->pdata), GFP_KERNEL); 1456 if (!dw->pdata) 1457 return -ENOMEM; 1458 1459 dw->regs = chip->regs; 1460 chip->dw = dw; 1461 1462 pm_runtime_get_sync(chip->dev); 1463 1464 if (!chip->pdata) { 1465 dw_params = dma_readl(dw, DW_PARAMS); 1466 dev_dbg(chip->dev, "DW_PARAMS: 0x%08x\n", dw_params); 1467 1468 autocfg = dw_params >> DW_PARAMS_EN & 1; 1469 if (!autocfg) { 1470 err = -EINVAL; 1471 goto err_pdata; 1472 } 1473 1474 /* Reassign the platform data pointer */ 1475 pdata = dw->pdata; 1476 1477 /* Get hardware configuration parameters */ 1478 pdata->nr_channels = (dw_params >> DW_PARAMS_NR_CHAN & 7) + 1; 1479 pdata->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER & 3) + 1; 1480 for (i = 0; i < pdata->nr_masters; i++) { 1481 pdata->data_width[i] = 1482 4 << (dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3); 1483 } 1484 pdata->block_size = dma_readl(dw, MAX_BLK_SIZE); 1485 1486 /* Fill platform data with the default values */ 1487 pdata->is_private = true; 1488 pdata->is_memcpy = true; 1489 pdata->chan_allocation_order = CHAN_ALLOCATION_ASCENDING; 1490 pdata->chan_priority = CHAN_PRIORITY_ASCENDING; 1491 } else if (chip->pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS) { 1492 err = -EINVAL; 1493 goto err_pdata; 1494 } else { 1495 memcpy(dw->pdata, chip->pdata, sizeof(*dw->pdata)); 1496 1497 /* Reassign the platform data pointer */ 1498 pdata = dw->pdata; 1499 } 1500 1501 dw->chan = devm_kcalloc(chip->dev, pdata->nr_channels, sizeof(*dw->chan), 1502 GFP_KERNEL); 1503 if (!dw->chan) { 1504 err = -ENOMEM; 1505 goto err_pdata; 1506 } 1507 1508 /* Calculate all channel mask before DMA setup */ 1509 dw->all_chan_mask = (1 << pdata->nr_channels) - 1; 1510 1511 /* Force dma off, just in case */ 1512 dw_dma_off(dw); 1513 1514 /* Create a pool of consistent memory blocks for hardware descriptors */ 1515 dw->desc_pool = dmam_pool_create("dw_dmac_desc_pool", chip->dev, 1516 sizeof(struct dw_desc), 4, 0); 1517 if (!dw->desc_pool) { 1518 dev_err(chip->dev, "No memory for descriptors dma pool\n"); 1519 err = -ENOMEM; 1520 goto err_pdata; 1521 } 1522 1523 tasklet_init(&dw->tasklet, dw_dma_tasklet, (unsigned long)dw); 1524 1525 err = request_irq(chip->irq, dw_dma_interrupt, IRQF_SHARED, 1526 "dw_dmac", dw); 1527 if (err) 1528 goto err_pdata; 1529 1530 INIT_LIST_HEAD(&dw->dma.channels); 1531 for (i = 0; i < pdata->nr_channels; i++) { 1532 struct dw_dma_chan *dwc = &dw->chan[i]; 1533 1534 dwc->chan.device = &dw->dma; 1535 dma_cookie_init(&dwc->chan); 1536 if (pdata->chan_allocation_order == CHAN_ALLOCATION_ASCENDING) 1537 list_add_tail(&dwc->chan.device_node, 1538 &dw->dma.channels); 1539 else 1540 list_add(&dwc->chan.device_node, &dw->dma.channels); 1541 1542 /* 7 is highest priority & 0 is lowest. */ 1543 if (pdata->chan_priority == CHAN_PRIORITY_ASCENDING) 1544 dwc->priority = pdata->nr_channels - i - 1; 1545 else 1546 dwc->priority = i; 1547 1548 dwc->ch_regs = &__dw_regs(dw)->CHAN[i]; 1549 spin_lock_init(&dwc->lock); 1550 dwc->mask = 1 << i; 1551 1552 INIT_LIST_HEAD(&dwc->active_list); 1553 INIT_LIST_HEAD(&dwc->queue); 1554 1555 channel_clear_bit(dw, CH_EN, dwc->mask); 1556 1557 dwc->direction = DMA_TRANS_NONE; 1558 1559 /* Hardware configuration */ 1560 if (autocfg) { 1561 unsigned int r = DW_DMA_MAX_NR_CHANNELS - i - 1; 1562 void __iomem *addr = &__dw_regs(dw)->DWC_PARAMS[r]; 1563 unsigned int dwc_params = dma_readl_native(addr); 1564 1565 dev_dbg(chip->dev, "DWC_PARAMS[%d]: 0x%08x\n", i, 1566 dwc_params); 1567 1568 /* 1569 * Decode maximum block size for given channel. The 1570 * stored 4 bit value represents blocks from 0x00 for 3 1571 * up to 0x0a for 4095. 1572 */ 1573 dwc->block_size = 1574 (4 << ((pdata->block_size >> 4 * i) & 0xf)) - 1; 1575 dwc->nollp = 1576 (dwc_params >> DWC_PARAMS_MBLK_EN & 0x1) == 0; 1577 } else { 1578 dwc->block_size = pdata->block_size; 1579 1580 /* Check if channel supports multi block transfer */ 1581 channel_writel(dwc, LLP, DWC_LLP_LOC(0xffffffff)); 1582 dwc->nollp = DWC_LLP_LOC(channel_readl(dwc, LLP)) == 0; 1583 channel_writel(dwc, LLP, 0); 1584 } 1585 } 1586 1587 /* Clear all interrupts on all channels. */ 1588 dma_writel(dw, CLEAR.XFER, dw->all_chan_mask); 1589 dma_writel(dw, CLEAR.BLOCK, dw->all_chan_mask); 1590 dma_writel(dw, CLEAR.SRC_TRAN, dw->all_chan_mask); 1591 dma_writel(dw, CLEAR.DST_TRAN, dw->all_chan_mask); 1592 dma_writel(dw, CLEAR.ERROR, dw->all_chan_mask); 1593 1594 /* Set capabilities */ 1595 dma_cap_set(DMA_SLAVE, dw->dma.cap_mask); 1596 if (pdata->is_private) 1597 dma_cap_set(DMA_PRIVATE, dw->dma.cap_mask); 1598 if (pdata->is_memcpy) 1599 dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask); 1600 1601 dw->dma.dev = chip->dev; 1602 dw->dma.device_alloc_chan_resources = dwc_alloc_chan_resources; 1603 dw->dma.device_free_chan_resources = dwc_free_chan_resources; 1604 1605 dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy; 1606 dw->dma.device_prep_slave_sg = dwc_prep_slave_sg; 1607 1608 dw->dma.device_config = dwc_config; 1609 dw->dma.device_pause = dwc_pause; 1610 dw->dma.device_resume = dwc_resume; 1611 dw->dma.device_terminate_all = dwc_terminate_all; 1612 1613 dw->dma.device_tx_status = dwc_tx_status; 1614 dw->dma.device_issue_pending = dwc_issue_pending; 1615 1616 /* DMA capabilities */ 1617 dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS; 1618 dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS; 1619 dw->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) | 1620 BIT(DMA_MEM_TO_MEM); 1621 dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; 1622 1623 err = dma_async_device_register(&dw->dma); 1624 if (err) 1625 goto err_dma_register; 1626 1627 dev_info(chip->dev, "DesignWare DMA Controller, %d channels\n", 1628 pdata->nr_channels); 1629 1630 pm_runtime_put_sync_suspend(chip->dev); 1631 1632 return 0; 1633 1634 err_dma_register: 1635 free_irq(chip->irq, dw); 1636 err_pdata: 1637 pm_runtime_put_sync_suspend(chip->dev); 1638 return err; 1639 } 1640 EXPORT_SYMBOL_GPL(dw_dma_probe); 1641 1642 int dw_dma_remove(struct dw_dma_chip *chip) 1643 { 1644 struct dw_dma *dw = chip->dw; 1645 struct dw_dma_chan *dwc, *_dwc; 1646 1647 pm_runtime_get_sync(chip->dev); 1648 1649 dw_dma_off(dw); 1650 dma_async_device_unregister(&dw->dma); 1651 1652 free_irq(chip->irq, dw); 1653 tasklet_kill(&dw->tasklet); 1654 1655 list_for_each_entry_safe(dwc, _dwc, &dw->dma.channels, 1656 chan.device_node) { 1657 list_del(&dwc->chan.device_node); 1658 channel_clear_bit(dw, CH_EN, dwc->mask); 1659 } 1660 1661 pm_runtime_put_sync_suspend(chip->dev); 1662 return 0; 1663 } 1664 EXPORT_SYMBOL_GPL(dw_dma_remove); 1665 1666 int dw_dma_disable(struct dw_dma_chip *chip) 1667 { 1668 struct dw_dma *dw = chip->dw; 1669 1670 dw_dma_off(dw); 1671 return 0; 1672 } 1673 EXPORT_SYMBOL_GPL(dw_dma_disable); 1674 1675 int dw_dma_enable(struct dw_dma_chip *chip) 1676 { 1677 struct dw_dma *dw = chip->dw; 1678 1679 dw_dma_on(dw); 1680 return 0; 1681 } 1682 EXPORT_SYMBOL_GPL(dw_dma_enable); 1683 1684 MODULE_LICENSE("GPL v2"); 1685 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller core driver"); 1686 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); 1687 MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>"); 1688