1/* 2 * SA11x0 DMAengine support 3 * 4 * Copyright (C) 2012 Russell King 5 * Derived in part from arch/arm/mach-sa1100/dma.c, 6 * Copyright (C) 2000, 2001 by Nicolas Pitre 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#include <linux/sched.h> 13#include <linux/device.h> 14#include <linux/dmaengine.h> 15#include <linux/init.h> 16#include <linux/interrupt.h> 17#include <linux/kernel.h> 18#include <linux/module.h> 19#include <linux/platform_device.h> 20#include <linux/sa11x0-dma.h> 21#include <linux/slab.h> 22#include <linux/spinlock.h> 23 24#include "virt-dma.h" 25 26#define NR_PHY_CHAN 6 27#define DMA_ALIGN 3 28#define DMA_MAX_SIZE 0x1fff 29#define DMA_CHUNK_SIZE 0x1000 30 31#define DMA_DDAR 0x00 32#define DMA_DCSR_S 0x04 33#define DMA_DCSR_C 0x08 34#define DMA_DCSR_R 0x0c 35#define DMA_DBSA 0x10 36#define DMA_DBTA 0x14 37#define DMA_DBSB 0x18 38#define DMA_DBTB 0x1c 39#define DMA_SIZE 0x20 40 41#define DCSR_RUN (1 << 0) 42#define DCSR_IE (1 << 1) 43#define DCSR_ERROR (1 << 2) 44#define DCSR_DONEA (1 << 3) 45#define DCSR_STRTA (1 << 4) 46#define DCSR_DONEB (1 << 5) 47#define DCSR_STRTB (1 << 6) 48#define DCSR_BIU (1 << 7) 49 50#define DDAR_RW (1 << 0) /* 0 = W, 1 = R */ 51#define DDAR_E (1 << 1) /* 0 = LE, 1 = BE */ 52#define DDAR_BS (1 << 2) /* 0 = BS4, 1 = BS8 */ 53#define DDAR_DW (1 << 3) /* 0 = 8b, 1 = 16b */ 54#define DDAR_Ser0UDCTr (0x0 << 4) 55#define DDAR_Ser0UDCRc (0x1 << 4) 56#define DDAR_Ser1SDLCTr (0x2 << 4) 57#define DDAR_Ser1SDLCRc (0x3 << 4) 58#define DDAR_Ser1UARTTr (0x4 << 4) 59#define DDAR_Ser1UARTRc (0x5 << 4) 60#define DDAR_Ser2ICPTr (0x6 << 4) 61#define DDAR_Ser2ICPRc (0x7 << 4) 62#define DDAR_Ser3UARTTr (0x8 << 4) 63#define DDAR_Ser3UARTRc (0x9 << 4) 64#define DDAR_Ser4MCP0Tr (0xa << 4) 65#define DDAR_Ser4MCP0Rc (0xb << 4) 66#define DDAR_Ser4MCP1Tr (0xc << 4) 67#define DDAR_Ser4MCP1Rc (0xd << 4) 68#define DDAR_Ser4SSPTr (0xe << 4) 69#define DDAR_Ser4SSPRc (0xf << 4) 70 71struct sa11x0_dma_sg { 72 u32 addr; 73 u32 len; 74}; 75 76struct sa11x0_dma_desc { 77 struct virt_dma_desc vd; 78 79 u32 ddar; 80 size_t size; 81 unsigned period; 82 bool cyclic; 83 84 unsigned sglen; 85 struct sa11x0_dma_sg sg[0]; 86}; 87 88struct sa11x0_dma_phy; 89 90struct sa11x0_dma_chan { 91 struct virt_dma_chan vc; 92 93 /* protected by c->vc.lock */ 94 struct sa11x0_dma_phy *phy; 95 enum dma_status status; 96 97 /* protected by d->lock */ 98 struct list_head node; 99 100 u32 ddar; 101 const char *name; 102}; 103 104struct sa11x0_dma_phy { 105 void __iomem *base; 106 struct sa11x0_dma_dev *dev; 107 unsigned num; 108 109 struct sa11x0_dma_chan *vchan; 110 111 /* Protected by c->vc.lock */ 112 unsigned sg_load; 113 struct sa11x0_dma_desc *txd_load; 114 unsigned sg_done; 115 struct sa11x0_dma_desc *txd_done; 116 u32 dbs[2]; 117 u32 dbt[2]; 118 u32 dcsr; 119}; 120 121struct sa11x0_dma_dev { 122 struct dma_device slave; 123 void __iomem *base; 124 spinlock_t lock; 125 struct tasklet_struct task; 126 struct list_head chan_pending; 127 struct sa11x0_dma_phy phy[NR_PHY_CHAN]; 128}; 129 130static struct sa11x0_dma_chan *to_sa11x0_dma_chan(struct dma_chan *chan) 131{ 132 return container_of(chan, struct sa11x0_dma_chan, vc.chan); 133} 134 135static struct sa11x0_dma_dev *to_sa11x0_dma(struct dma_device *dmadev) 136{ 137 return container_of(dmadev, struct sa11x0_dma_dev, slave); 138} 139 140static struct sa11x0_dma_desc *sa11x0_dma_next_desc(struct sa11x0_dma_chan *c) 141{ 142 struct virt_dma_desc *vd = vchan_next_desc(&c->vc); 143 144 return vd ? container_of(vd, struct sa11x0_dma_desc, vd) : NULL; 145} 146 147static void sa11x0_dma_free_desc(struct virt_dma_desc *vd) 148{ 149 kfree(container_of(vd, struct sa11x0_dma_desc, vd)); 150} 151 152static void sa11x0_dma_start_desc(struct sa11x0_dma_phy *p, struct sa11x0_dma_desc *txd) 153{ 154 list_del(&txd->vd.node); 155 p->txd_load = txd; 156 p->sg_load = 0; 157 158 dev_vdbg(p->dev->slave.dev, "pchan %u: txd %p[%x]: starting: DDAR:%x\n", 159 p->num, &txd->vd, txd->vd.tx.cookie, txd->ddar); 160} 161 162static void noinline sa11x0_dma_start_sg(struct sa11x0_dma_phy *p, 163 struct sa11x0_dma_chan *c) 164{ 165 struct sa11x0_dma_desc *txd = p->txd_load; 166 struct sa11x0_dma_sg *sg; 167 void __iomem *base = p->base; 168 unsigned dbsx, dbtx; 169 u32 dcsr; 170 171 if (!txd) 172 return; 173 174 dcsr = readl_relaxed(base + DMA_DCSR_R); 175 176 /* Don't try to load the next transfer if both buffers are started */ 177 if ((dcsr & (DCSR_STRTA | DCSR_STRTB)) == (DCSR_STRTA | DCSR_STRTB)) 178 return; 179 180 if (p->sg_load == txd->sglen) { 181 if (!txd->cyclic) { 182 struct sa11x0_dma_desc *txn = sa11x0_dma_next_desc(c); 183 184 /* 185 * We have reached the end of the current descriptor. 186 * Peek at the next descriptor, and if compatible with 187 * the current, start processing it. 188 */ 189 if (txn && txn->ddar == txd->ddar) { 190 txd = txn; 191 sa11x0_dma_start_desc(p, txn); 192 } else { 193 p->txd_load = NULL; 194 return; 195 } 196 } else { 197 /* Cyclic: reset back to beginning */ 198 p->sg_load = 0; 199 } 200 } 201 202 sg = &txd->sg[p->sg_load++]; 203 204 /* Select buffer to load according to channel status */ 205 if (((dcsr & (DCSR_BIU | DCSR_STRTB)) == (DCSR_BIU | DCSR_STRTB)) || 206 ((dcsr & (DCSR_BIU | DCSR_STRTA)) == 0)) { 207 dbsx = DMA_DBSA; 208 dbtx = DMA_DBTA; 209 dcsr = DCSR_STRTA | DCSR_IE | DCSR_RUN; 210 } else { 211 dbsx = DMA_DBSB; 212 dbtx = DMA_DBTB; 213 dcsr = DCSR_STRTB | DCSR_IE | DCSR_RUN; 214 } 215 216 writel_relaxed(sg->addr, base + dbsx); 217 writel_relaxed(sg->len, base + dbtx); 218 writel(dcsr, base + DMA_DCSR_S); 219 220 dev_dbg(p->dev->slave.dev, "pchan %u: load: DCSR:%02x DBS%c:%08x DBT%c:%08x\n", 221 p->num, dcsr, 222 'A' + (dbsx == DMA_DBSB), sg->addr, 223 'A' + (dbtx == DMA_DBTB), sg->len); 224} 225 226static void noinline sa11x0_dma_complete(struct sa11x0_dma_phy *p, 227 struct sa11x0_dma_chan *c) 228{ 229 struct sa11x0_dma_desc *txd = p->txd_done; 230 231 if (++p->sg_done == txd->sglen) { 232 if (!txd->cyclic) { 233 vchan_cookie_complete(&txd->vd); 234 235 p->sg_done = 0; 236 p->txd_done = p->txd_load; 237 238 if (!p->txd_done) 239 tasklet_schedule(&p->dev->task); 240 } else { 241 if ((p->sg_done % txd->period) == 0) 242 vchan_cyclic_callback(&txd->vd); 243 244 /* Cyclic: reset back to beginning */ 245 p->sg_done = 0; 246 } 247 } 248 249 sa11x0_dma_start_sg(p, c); 250} 251 252static irqreturn_t sa11x0_dma_irq(int irq, void *dev_id) 253{ 254 struct sa11x0_dma_phy *p = dev_id; 255 struct sa11x0_dma_dev *d = p->dev; 256 struct sa11x0_dma_chan *c; 257 u32 dcsr; 258 259 dcsr = readl_relaxed(p->base + DMA_DCSR_R); 260 if (!(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB))) 261 return IRQ_NONE; 262 263 /* Clear reported status bits */ 264 writel_relaxed(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB), 265 p->base + DMA_DCSR_C); 266 267 dev_dbg(d->slave.dev, "pchan %u: irq: DCSR:%02x\n", p->num, dcsr); 268 269 if (dcsr & DCSR_ERROR) { 270 dev_err(d->slave.dev, "pchan %u: error. DCSR:%02x DDAR:%08x DBSA:%08x DBTA:%08x DBSB:%08x DBTB:%08x\n", 271 p->num, dcsr, 272 readl_relaxed(p->base + DMA_DDAR), 273 readl_relaxed(p->base + DMA_DBSA), 274 readl_relaxed(p->base + DMA_DBTA), 275 readl_relaxed(p->base + DMA_DBSB), 276 readl_relaxed(p->base + DMA_DBTB)); 277 } 278 279 c = p->vchan; 280 if (c) { 281 unsigned long flags; 282 283 spin_lock_irqsave(&c->vc.lock, flags); 284 /* 285 * Now that we're holding the lock, check that the vchan 286 * really is associated with this pchan before touching the 287 * hardware. This should always succeed, because we won't 288 * change p->vchan or c->phy while the channel is actively 289 * transferring. 290 */ 291 if (c->phy == p) { 292 if (dcsr & DCSR_DONEA) 293 sa11x0_dma_complete(p, c); 294 if (dcsr & DCSR_DONEB) 295 sa11x0_dma_complete(p, c); 296 } 297 spin_unlock_irqrestore(&c->vc.lock, flags); 298 } 299 300 return IRQ_HANDLED; 301} 302 303static void sa11x0_dma_start_txd(struct sa11x0_dma_chan *c) 304{ 305 struct sa11x0_dma_desc *txd = sa11x0_dma_next_desc(c); 306 307 /* If the issued list is empty, we have no further txds to process */ 308 if (txd) { 309 struct sa11x0_dma_phy *p = c->phy; 310 311 sa11x0_dma_start_desc(p, txd); 312 p->txd_done = txd; 313 p->sg_done = 0; 314 315 /* The channel should not have any transfers started */ 316 WARN_ON(readl_relaxed(p->base + DMA_DCSR_R) & 317 (DCSR_STRTA | DCSR_STRTB)); 318 319 /* Clear the run and start bits before changing DDAR */ 320 writel_relaxed(DCSR_RUN | DCSR_STRTA | DCSR_STRTB, 321 p->base + DMA_DCSR_C); 322 writel_relaxed(txd->ddar, p->base + DMA_DDAR); 323 324 /* Try to start both buffers */ 325 sa11x0_dma_start_sg(p, c); 326 sa11x0_dma_start_sg(p, c); 327 } 328} 329 330static void sa11x0_dma_tasklet(unsigned long arg) 331{ 332 struct sa11x0_dma_dev *d = (struct sa11x0_dma_dev *)arg; 333 struct sa11x0_dma_phy *p; 334 struct sa11x0_dma_chan *c; 335 unsigned pch, pch_alloc = 0; 336 337 dev_dbg(d->slave.dev, "tasklet enter\n"); 338 339 list_for_each_entry(c, &d->slave.channels, vc.chan.device_node) { 340 spin_lock_irq(&c->vc.lock); 341 p = c->phy; 342 if (p && !p->txd_done) { 343 sa11x0_dma_start_txd(c); 344 if (!p->txd_done) { 345 /* No current txd associated with this channel */ 346 dev_dbg(d->slave.dev, "pchan %u: free\n", p->num); 347 348 /* Mark this channel free */ 349 c->phy = NULL; 350 p->vchan = NULL; 351 } 352 } 353 spin_unlock_irq(&c->vc.lock); 354 } 355 356 spin_lock_irq(&d->lock); 357 for (pch = 0; pch < NR_PHY_CHAN; pch++) { 358 p = &d->phy[pch]; 359 360 if (p->vchan == NULL && !list_empty(&d->chan_pending)) { 361 c = list_first_entry(&d->chan_pending, 362 struct sa11x0_dma_chan, node); 363 list_del_init(&c->node); 364 365 pch_alloc |= 1 << pch; 366 367 /* Mark this channel allocated */ 368 p->vchan = c; 369 370 dev_dbg(d->slave.dev, "pchan %u: alloc vchan %p\n", pch, &c->vc); 371 } 372 } 373 spin_unlock_irq(&d->lock); 374 375 for (pch = 0; pch < NR_PHY_CHAN; pch++) { 376 if (pch_alloc & (1 << pch)) { 377 p = &d->phy[pch]; 378 c = p->vchan; 379 380 spin_lock_irq(&c->vc.lock); 381 c->phy = p; 382 383 sa11x0_dma_start_txd(c); 384 spin_unlock_irq(&c->vc.lock); 385 } 386 } 387 388 dev_dbg(d->slave.dev, "tasklet exit\n"); 389} 390 391 392static int sa11x0_dma_alloc_chan_resources(struct dma_chan *chan) 393{ 394 return 0; 395} 396 397static void sa11x0_dma_free_chan_resources(struct dma_chan *chan) 398{ 399 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); 400 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); 401 unsigned long flags; 402 403 spin_lock_irqsave(&d->lock, flags); 404 list_del_init(&c->node); 405 spin_unlock_irqrestore(&d->lock, flags); 406 407 vchan_free_chan_resources(&c->vc); 408} 409 410static dma_addr_t sa11x0_dma_pos(struct sa11x0_dma_phy *p) 411{ 412 unsigned reg; 413 u32 dcsr; 414 415 dcsr = readl_relaxed(p->base + DMA_DCSR_R); 416 417 if ((dcsr & (DCSR_BIU | DCSR_STRTA)) == DCSR_STRTA || 418 (dcsr & (DCSR_BIU | DCSR_STRTB)) == DCSR_BIU) 419 reg = DMA_DBSA; 420 else 421 reg = DMA_DBSB; 422 423 return readl_relaxed(p->base + reg); 424} 425 426static enum dma_status sa11x0_dma_tx_status(struct dma_chan *chan, 427 dma_cookie_t cookie, struct dma_tx_state *state) 428{ 429 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); 430 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); 431 struct sa11x0_dma_phy *p; 432 struct virt_dma_desc *vd; 433 unsigned long flags; 434 enum dma_status ret; 435 436 ret = dma_cookie_status(&c->vc.chan, cookie, state); 437 if (ret == DMA_COMPLETE) 438 return ret; 439 440 if (!state) 441 return c->status; 442 443 spin_lock_irqsave(&c->vc.lock, flags); 444 p = c->phy; 445 446 /* 447 * If the cookie is on our issue queue, then the residue is 448 * its total size. 449 */ 450 vd = vchan_find_desc(&c->vc, cookie); 451 if (vd) { 452 state->residue = container_of(vd, struct sa11x0_dma_desc, vd)->size; 453 } else if (!p) { 454 state->residue = 0; 455 } else { 456 struct sa11x0_dma_desc *txd; 457 size_t bytes = 0; 458 459 if (p->txd_done && p->txd_done->vd.tx.cookie == cookie) 460 txd = p->txd_done; 461 else if (p->txd_load && p->txd_load->vd.tx.cookie == cookie) 462 txd = p->txd_load; 463 else 464 txd = NULL; 465 466 ret = c->status; 467 if (txd) { 468 dma_addr_t addr = sa11x0_dma_pos(p); 469 unsigned i; 470 471 dev_vdbg(d->slave.dev, "tx_status: addr:%x\n", addr); 472 473 for (i = 0; i < txd->sglen; i++) { 474 dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x\n", 475 i, txd->sg[i].addr, txd->sg[i].len); 476 if (addr >= txd->sg[i].addr && 477 addr < txd->sg[i].addr + txd->sg[i].len) { 478 unsigned len; 479 480 len = txd->sg[i].len - 481 (addr - txd->sg[i].addr); 482 dev_vdbg(d->slave.dev, "tx_status: [%u] +%x\n", 483 i, len); 484 bytes += len; 485 i++; 486 break; 487 } 488 } 489 for (; i < txd->sglen; i++) { 490 dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x ++\n", 491 i, txd->sg[i].addr, txd->sg[i].len); 492 bytes += txd->sg[i].len; 493 } 494 } 495 state->residue = bytes; 496 } 497 spin_unlock_irqrestore(&c->vc.lock, flags); 498 499 dev_vdbg(d->slave.dev, "tx_status: bytes 0x%zx\n", state->residue); 500 501 return ret; 502} 503 504/* 505 * Move pending txds to the issued list, and re-init pending list. 506 * If not already pending, add this channel to the list of pending 507 * channels and trigger the tasklet to run. 508 */ 509static void sa11x0_dma_issue_pending(struct dma_chan *chan) 510{ 511 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); 512 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); 513 unsigned long flags; 514 515 spin_lock_irqsave(&c->vc.lock, flags); 516 if (vchan_issue_pending(&c->vc)) { 517 if (!c->phy) { 518 spin_lock(&d->lock); 519 if (list_empty(&c->node)) { 520 list_add_tail(&c->node, &d->chan_pending); 521 tasklet_schedule(&d->task); 522 dev_dbg(d->slave.dev, "vchan %p: issued\n", &c->vc); 523 } 524 spin_unlock(&d->lock); 525 } 526 } else 527 dev_dbg(d->slave.dev, "vchan %p: nothing to issue\n", &c->vc); 528 spin_unlock_irqrestore(&c->vc.lock, flags); 529} 530 531static struct dma_async_tx_descriptor *sa11x0_dma_prep_slave_sg( 532 struct dma_chan *chan, struct scatterlist *sg, unsigned int sglen, 533 enum dma_transfer_direction dir, unsigned long flags, void *context) 534{ 535 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); 536 struct sa11x0_dma_desc *txd; 537 struct scatterlist *sgent; 538 unsigned i, j = sglen; 539 size_t size = 0; 540 541 /* SA11x0 channels can only operate in their native direction */ 542 if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) { 543 dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n", 544 &c->vc, c->ddar, dir); 545 return NULL; 546 } 547 548 /* Do not allow zero-sized txds */ 549 if (sglen == 0) 550 return NULL; 551 552 for_each_sg(sg, sgent, sglen, i) { 553 dma_addr_t addr = sg_dma_address(sgent); 554 unsigned int len = sg_dma_len(sgent); 555 556 if (len > DMA_MAX_SIZE) 557 j += DIV_ROUND_UP(len, DMA_MAX_SIZE & ~DMA_ALIGN) - 1; 558 if (addr & DMA_ALIGN) { 559 dev_dbg(chan->device->dev, "vchan %p: bad buffer alignment: %08x\n", 560 &c->vc, addr); 561 return NULL; 562 } 563 } 564 565 txd = kzalloc(sizeof(*txd) + j * sizeof(txd->sg[0]), GFP_ATOMIC); 566 if (!txd) { 567 dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc); 568 return NULL; 569 } 570 571 j = 0; 572 for_each_sg(sg, sgent, sglen, i) { 573 dma_addr_t addr = sg_dma_address(sgent); 574 unsigned len = sg_dma_len(sgent); 575 576 size += len; 577 578 do { 579 unsigned tlen = len; 580 581 /* 582 * Check whether the transfer will fit. If not, try 583 * to split the transfer up such that we end up with 584 * equal chunks - but make sure that we preserve the 585 * alignment. This avoids small segments. 586 */ 587 if (tlen > DMA_MAX_SIZE) { 588 unsigned mult = DIV_ROUND_UP(tlen, 589 DMA_MAX_SIZE & ~DMA_ALIGN); 590 591 tlen = (tlen / mult) & ~DMA_ALIGN; 592 } 593 594 txd->sg[j].addr = addr; 595 txd->sg[j].len = tlen; 596 597 addr += tlen; 598 len -= tlen; 599 j++; 600 } while (len); 601 } 602 603 txd->ddar = c->ddar; 604 txd->size = size; 605 txd->sglen = j; 606 607 dev_dbg(chan->device->dev, "vchan %p: txd %p: size %u nr %u\n", 608 &c->vc, &txd->vd, txd->size, txd->sglen); 609 610 return vchan_tx_prep(&c->vc, &txd->vd, flags); 611} 612 613static struct dma_async_tx_descriptor *sa11x0_dma_prep_dma_cyclic( 614 struct dma_chan *chan, dma_addr_t addr, size_t size, size_t period, 615 enum dma_transfer_direction dir, unsigned long flags) 616{ 617 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); 618 struct sa11x0_dma_desc *txd; 619 unsigned i, j, k, sglen, sgperiod; 620 621 /* SA11x0 channels can only operate in their native direction */ 622 if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) { 623 dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n", 624 &c->vc, c->ddar, dir); 625 return NULL; 626 } 627 628 sgperiod = DIV_ROUND_UP(period, DMA_MAX_SIZE & ~DMA_ALIGN); 629 sglen = size * sgperiod / period; 630 631 /* Do not allow zero-sized txds */ 632 if (sglen == 0) 633 return NULL; 634 635 txd = kzalloc(sizeof(*txd) + sglen * sizeof(txd->sg[0]), GFP_ATOMIC); 636 if (!txd) { 637 dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc); 638 return NULL; 639 } 640 641 for (i = k = 0; i < size / period; i++) { 642 size_t tlen, len = period; 643 644 for (j = 0; j < sgperiod; j++, k++) { 645 tlen = len; 646 647 if (tlen > DMA_MAX_SIZE) { 648 unsigned mult = DIV_ROUND_UP(tlen, DMA_MAX_SIZE & ~DMA_ALIGN); 649 tlen = (tlen / mult) & ~DMA_ALIGN; 650 } 651 652 txd->sg[k].addr = addr; 653 txd->sg[k].len = tlen; 654 addr += tlen; 655 len -= tlen; 656 } 657 658 WARN_ON(len != 0); 659 } 660 661 WARN_ON(k != sglen); 662 663 txd->ddar = c->ddar; 664 txd->size = size; 665 txd->sglen = sglen; 666 txd->cyclic = 1; 667 txd->period = sgperiod; 668 669 return vchan_tx_prep(&c->vc, &txd->vd, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 670} 671 672static int sa11x0_dma_slave_config(struct sa11x0_dma_chan *c, struct dma_slave_config *cfg) 673{ 674 u32 ddar = c->ddar & ((0xf << 4) | DDAR_RW); 675 dma_addr_t addr; 676 enum dma_slave_buswidth width; 677 u32 maxburst; 678 679 if (ddar & DDAR_RW) { 680 addr = cfg->src_addr; 681 width = cfg->src_addr_width; 682 maxburst = cfg->src_maxburst; 683 } else { 684 addr = cfg->dst_addr; 685 width = cfg->dst_addr_width; 686 maxburst = cfg->dst_maxburst; 687 } 688 689 if ((width != DMA_SLAVE_BUSWIDTH_1_BYTE && 690 width != DMA_SLAVE_BUSWIDTH_2_BYTES) || 691 (maxburst != 4 && maxburst != 8)) 692 return -EINVAL; 693 694 if (width == DMA_SLAVE_BUSWIDTH_2_BYTES) 695 ddar |= DDAR_DW; 696 if (maxburst == 8) 697 ddar |= DDAR_BS; 698 699 dev_dbg(c->vc.chan.device->dev, "vchan %p: dma_slave_config addr %x width %u burst %u\n", 700 &c->vc, addr, width, maxburst); 701 702 c->ddar = ddar | (addr & 0xf0000000) | (addr & 0x003ffffc) << 6; 703 704 return 0; 705} 706 707static int sa11x0_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, 708 unsigned long arg) 709{ 710 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); 711 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); 712 struct sa11x0_dma_phy *p; 713 LIST_HEAD(head); 714 unsigned long flags; 715 int ret; 716 717 switch (cmd) { 718 case DMA_SLAVE_CONFIG: 719 return sa11x0_dma_slave_config(c, (struct dma_slave_config *)arg); 720 721 case DMA_TERMINATE_ALL: 722 dev_dbg(d->slave.dev, "vchan %p: terminate all\n", &c->vc); 723 /* Clear the tx descriptor lists */ 724 spin_lock_irqsave(&c->vc.lock, flags); 725 vchan_get_all_descriptors(&c->vc, &head); 726 727 p = c->phy; 728 if (p) { 729 dev_dbg(d->slave.dev, "pchan %u: terminating\n", p->num); 730 /* vchan is assigned to a pchan - stop the channel */ 731 writel(DCSR_RUN | DCSR_IE | 732 DCSR_STRTA | DCSR_DONEA | 733 DCSR_STRTB | DCSR_DONEB, 734 p->base + DMA_DCSR_C); 735 736 if (p->txd_load) { 737 if (p->txd_load != p->txd_done) 738 list_add_tail(&p->txd_load->vd.node, &head); 739 p->txd_load = NULL; 740 } 741 if (p->txd_done) { 742 list_add_tail(&p->txd_done->vd.node, &head); 743 p->txd_done = NULL; 744 } 745 c->phy = NULL; 746 spin_lock(&d->lock); 747 p->vchan = NULL; 748 spin_unlock(&d->lock); 749 tasklet_schedule(&d->task); 750 } 751 spin_unlock_irqrestore(&c->vc.lock, flags); 752 vchan_dma_desc_free_list(&c->vc, &head); 753 ret = 0; 754 break; 755 756 case DMA_PAUSE: 757 dev_dbg(d->slave.dev, "vchan %p: pause\n", &c->vc); 758 spin_lock_irqsave(&c->vc.lock, flags); 759 if (c->status == DMA_IN_PROGRESS) { 760 c->status = DMA_PAUSED; 761 762 p = c->phy; 763 if (p) { 764 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C); 765 } else { 766 spin_lock(&d->lock); 767 list_del_init(&c->node); 768 spin_unlock(&d->lock); 769 } 770 } 771 spin_unlock_irqrestore(&c->vc.lock, flags); 772 ret = 0; 773 break; 774 775 case DMA_RESUME: 776 dev_dbg(d->slave.dev, "vchan %p: resume\n", &c->vc); 777 spin_lock_irqsave(&c->vc.lock, flags); 778 if (c->status == DMA_PAUSED) { 779 c->status = DMA_IN_PROGRESS; 780 781 p = c->phy; 782 if (p) { 783 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_S); 784 } else if (!list_empty(&c->vc.desc_issued)) { 785 spin_lock(&d->lock); 786 list_add_tail(&c->node, &d->chan_pending); 787 spin_unlock(&d->lock); 788 } 789 } 790 spin_unlock_irqrestore(&c->vc.lock, flags); 791 ret = 0; 792 break; 793 794 default: 795 ret = -ENXIO; 796 break; 797 } 798 799 return ret; 800} 801 802struct sa11x0_dma_channel_desc { 803 u32 ddar; 804 const char *name; 805}; 806 807#define CD(d1, d2) { .ddar = DDAR_##d1 | d2, .name = #d1 } 808static const struct sa11x0_dma_channel_desc chan_desc[] = { 809 CD(Ser0UDCTr, 0), 810 CD(Ser0UDCRc, DDAR_RW), 811 CD(Ser1SDLCTr, 0), 812 CD(Ser1SDLCRc, DDAR_RW), 813 CD(Ser1UARTTr, 0), 814 CD(Ser1UARTRc, DDAR_RW), 815 CD(Ser2ICPTr, 0), 816 CD(Ser2ICPRc, DDAR_RW), 817 CD(Ser3UARTTr, 0), 818 CD(Ser3UARTRc, DDAR_RW), 819 CD(Ser4MCP0Tr, 0), 820 CD(Ser4MCP0Rc, DDAR_RW), 821 CD(Ser4MCP1Tr, 0), 822 CD(Ser4MCP1Rc, DDAR_RW), 823 CD(Ser4SSPTr, 0), 824 CD(Ser4SSPRc, DDAR_RW), 825}; 826 827static int sa11x0_dma_init_dmadev(struct dma_device *dmadev, 828 struct device *dev) 829{ 830 unsigned i; 831 832 dmadev->chancnt = ARRAY_SIZE(chan_desc); 833 INIT_LIST_HEAD(&dmadev->channels); 834 dmadev->dev = dev; 835 dmadev->device_alloc_chan_resources = sa11x0_dma_alloc_chan_resources; 836 dmadev->device_free_chan_resources = sa11x0_dma_free_chan_resources; 837 dmadev->device_control = sa11x0_dma_control; 838 dmadev->device_tx_status = sa11x0_dma_tx_status; 839 dmadev->device_issue_pending = sa11x0_dma_issue_pending; 840 841 for (i = 0; i < dmadev->chancnt; i++) { 842 struct sa11x0_dma_chan *c; 843 844 c = kzalloc(sizeof(*c), GFP_KERNEL); 845 if (!c) { 846 dev_err(dev, "no memory for channel %u\n", i); 847 return -ENOMEM; 848 } 849 850 c->status = DMA_IN_PROGRESS; 851 c->ddar = chan_desc[i].ddar; 852 c->name = chan_desc[i].name; 853 INIT_LIST_HEAD(&c->node); 854 855 c->vc.desc_free = sa11x0_dma_free_desc; 856 vchan_init(&c->vc, dmadev); 857 } 858 859 return dma_async_device_register(dmadev); 860} 861 862static int sa11x0_dma_request_irq(struct platform_device *pdev, int nr, 863 void *data) 864{ 865 int irq = platform_get_irq(pdev, nr); 866 867 if (irq <= 0) 868 return -ENXIO; 869 870 return request_irq(irq, sa11x0_dma_irq, 0, dev_name(&pdev->dev), data); 871} 872 873static void sa11x0_dma_free_irq(struct platform_device *pdev, int nr, 874 void *data) 875{ 876 int irq = platform_get_irq(pdev, nr); 877 if (irq > 0) 878 free_irq(irq, data); 879} 880 881static void sa11x0_dma_free_channels(struct dma_device *dmadev) 882{ 883 struct sa11x0_dma_chan *c, *cn; 884 885 list_for_each_entry_safe(c, cn, &dmadev->channels, vc.chan.device_node) { 886 list_del(&c->vc.chan.device_node); 887 tasklet_kill(&c->vc.task); 888 kfree(c); 889 } 890} 891 892static int sa11x0_dma_probe(struct platform_device *pdev) 893{ 894 struct sa11x0_dma_dev *d; 895 struct resource *res; 896 unsigned i; 897 int ret; 898 899 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 900 if (!res) 901 return -ENXIO; 902 903 d = kzalloc(sizeof(*d), GFP_KERNEL); 904 if (!d) { 905 ret = -ENOMEM; 906 goto err_alloc; 907 } 908 909 spin_lock_init(&d->lock); 910 INIT_LIST_HEAD(&d->chan_pending); 911 912 d->base = ioremap(res->start, resource_size(res)); 913 if (!d->base) { 914 ret = -ENOMEM; 915 goto err_ioremap; 916 } 917 918 tasklet_init(&d->task, sa11x0_dma_tasklet, (unsigned long)d); 919 920 for (i = 0; i < NR_PHY_CHAN; i++) { 921 struct sa11x0_dma_phy *p = &d->phy[i]; 922 923 p->dev = d; 924 p->num = i; 925 p->base = d->base + i * DMA_SIZE; 926 writel_relaxed(DCSR_RUN | DCSR_IE | DCSR_ERROR | 927 DCSR_DONEA | DCSR_STRTA | DCSR_DONEB | DCSR_STRTB, 928 p->base + DMA_DCSR_C); 929 writel_relaxed(0, p->base + DMA_DDAR); 930 931 ret = sa11x0_dma_request_irq(pdev, i, p); 932 if (ret) { 933 while (i) { 934 i--; 935 sa11x0_dma_free_irq(pdev, i, &d->phy[i]); 936 } 937 goto err_irq; 938 } 939 } 940 941 dma_cap_set(DMA_SLAVE, d->slave.cap_mask); 942 dma_cap_set(DMA_CYCLIC, d->slave.cap_mask); 943 d->slave.device_prep_slave_sg = sa11x0_dma_prep_slave_sg; 944 d->slave.device_prep_dma_cyclic = sa11x0_dma_prep_dma_cyclic; 945 ret = sa11x0_dma_init_dmadev(&d->slave, &pdev->dev); 946 if (ret) { 947 dev_warn(d->slave.dev, "failed to register slave async device: %d\n", 948 ret); 949 goto err_slave_reg; 950 } 951 952 platform_set_drvdata(pdev, d); 953 return 0; 954 955 err_slave_reg: 956 sa11x0_dma_free_channels(&d->slave); 957 for (i = 0; i < NR_PHY_CHAN; i++) 958 sa11x0_dma_free_irq(pdev, i, &d->phy[i]); 959 err_irq: 960 tasklet_kill(&d->task); 961 iounmap(d->base); 962 err_ioremap: 963 kfree(d); 964 err_alloc: 965 return ret; 966} 967 968static int sa11x0_dma_remove(struct platform_device *pdev) 969{ 970 struct sa11x0_dma_dev *d = platform_get_drvdata(pdev); 971 unsigned pch; 972 973 dma_async_device_unregister(&d->slave); 974 975 sa11x0_dma_free_channels(&d->slave); 976 for (pch = 0; pch < NR_PHY_CHAN; pch++) 977 sa11x0_dma_free_irq(pdev, pch, &d->phy[pch]); 978 tasklet_kill(&d->task); 979 iounmap(d->base); 980 kfree(d); 981 982 return 0; 983} 984 985static int sa11x0_dma_suspend(struct device *dev) 986{ 987 struct sa11x0_dma_dev *d = dev_get_drvdata(dev); 988 unsigned pch; 989 990 for (pch = 0; pch < NR_PHY_CHAN; pch++) { 991 struct sa11x0_dma_phy *p = &d->phy[pch]; 992 u32 dcsr, saved_dcsr; 993 994 dcsr = saved_dcsr = readl_relaxed(p->base + DMA_DCSR_R); 995 if (dcsr & DCSR_RUN) { 996 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C); 997 dcsr = readl_relaxed(p->base + DMA_DCSR_R); 998 } 999 1000 saved_dcsr &= DCSR_RUN | DCSR_IE; 1001 if (dcsr & DCSR_BIU) { 1002 p->dbs[0] = readl_relaxed(p->base + DMA_DBSB); 1003 p->dbt[0] = readl_relaxed(p->base + DMA_DBTB); 1004 p->dbs[1] = readl_relaxed(p->base + DMA_DBSA); 1005 p->dbt[1] = readl_relaxed(p->base + DMA_DBTA); 1006 saved_dcsr |= (dcsr & DCSR_STRTA ? DCSR_STRTB : 0) | 1007 (dcsr & DCSR_STRTB ? DCSR_STRTA : 0); 1008 } else { 1009 p->dbs[0] = readl_relaxed(p->base + DMA_DBSA); 1010 p->dbt[0] = readl_relaxed(p->base + DMA_DBTA); 1011 p->dbs[1] = readl_relaxed(p->base + DMA_DBSB); 1012 p->dbt[1] = readl_relaxed(p->base + DMA_DBTB); 1013 saved_dcsr |= dcsr & (DCSR_STRTA | DCSR_STRTB); 1014 } 1015 p->dcsr = saved_dcsr; 1016 1017 writel(DCSR_STRTA | DCSR_STRTB, p->base + DMA_DCSR_C); 1018 } 1019 1020 return 0; 1021} 1022 1023static int sa11x0_dma_resume(struct device *dev) 1024{ 1025 struct sa11x0_dma_dev *d = dev_get_drvdata(dev); 1026 unsigned pch; 1027 1028 for (pch = 0; pch < NR_PHY_CHAN; pch++) { 1029 struct sa11x0_dma_phy *p = &d->phy[pch]; 1030 struct sa11x0_dma_desc *txd = NULL; 1031 u32 dcsr = readl_relaxed(p->base + DMA_DCSR_R); 1032 1033 WARN_ON(dcsr & (DCSR_BIU | DCSR_STRTA | DCSR_STRTB | DCSR_RUN)); 1034 1035 if (p->txd_done) 1036 txd = p->txd_done; 1037 else if (p->txd_load) 1038 txd = p->txd_load; 1039 1040 if (!txd) 1041 continue; 1042 1043 writel_relaxed(txd->ddar, p->base + DMA_DDAR); 1044 1045 writel_relaxed(p->dbs[0], p->base + DMA_DBSA); 1046 writel_relaxed(p->dbt[0], p->base + DMA_DBTA); 1047 writel_relaxed(p->dbs[1], p->base + DMA_DBSB); 1048 writel_relaxed(p->dbt[1], p->base + DMA_DBTB); 1049 writel_relaxed(p->dcsr, p->base + DMA_DCSR_S); 1050 } 1051 1052 return 0; 1053} 1054 1055static const struct dev_pm_ops sa11x0_dma_pm_ops = { 1056 .suspend_noirq = sa11x0_dma_suspend, 1057 .resume_noirq = sa11x0_dma_resume, 1058 .freeze_noirq = sa11x0_dma_suspend, 1059 .thaw_noirq = sa11x0_dma_resume, 1060 .poweroff_noirq = sa11x0_dma_suspend, 1061 .restore_noirq = sa11x0_dma_resume, 1062}; 1063 1064static struct platform_driver sa11x0_dma_driver = { 1065 .driver = { 1066 .name = "sa11x0-dma", 1067 .owner = THIS_MODULE, 1068 .pm = &sa11x0_dma_pm_ops, 1069 }, 1070 .probe = sa11x0_dma_probe, 1071 .remove = sa11x0_dma_remove, 1072}; 1073 1074bool sa11x0_dma_filter_fn(struct dma_chan *chan, void *param) 1075{ 1076 if (chan->device->dev->driver == &sa11x0_dma_driver.driver) { 1077 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); 1078 const char *p = param; 1079 1080 return !strcmp(c->name, p); 1081 } 1082 return false; 1083} 1084EXPORT_SYMBOL(sa11x0_dma_filter_fn); 1085 1086static int __init sa11x0_dma_init(void) 1087{ 1088 return platform_driver_register(&sa11x0_dma_driver); 1089} 1090subsys_initcall(sa11x0_dma_init); 1091 1092static void __exit sa11x0_dma_exit(void) 1093{ 1094 platform_driver_unregister(&sa11x0_dma_driver); 1095} 1096module_exit(sa11x0_dma_exit); 1097 1098MODULE_AUTHOR("Russell King"); 1099MODULE_DESCRIPTION("SA-11x0 DMA driver"); 1100MODULE_LICENSE("GPL v2"); 1101MODULE_ALIAS("platform:sa11x0-dma"); 1102