1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Topcliff PCH DMA controller driver 4 * Copyright (c) 2010 Intel Corporation 5 * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd. 6 */ 7 8#include <linux/dmaengine.h> 9#include <linux/dma-mapping.h> 10#include <linux/init.h> 11#include <linux/pci.h> 12#include <linux/slab.h> 13#include <linux/interrupt.h> 14#include <linux/module.h> 15#include <linux/pch_dma.h> 16 17#include "dmaengine.h" 18 19#define DRV_NAME "pch-dma" 20 21#define DMA_CTL0_DISABLE 0x0 22#define DMA_CTL0_SG 0x1 23#define DMA_CTL0_ONESHOT 0x2 24#define DMA_CTL0_MODE_MASK_BITS 0x3 25#define DMA_CTL0_DIR_SHIFT_BITS 2 26#define DMA_CTL0_BITS_PER_CH 4 27 28#define DMA_CTL2_START_SHIFT_BITS 8 29#define DMA_CTL2_IRQ_ENABLE_MASK ((1UL << DMA_CTL2_START_SHIFT_BITS) - 1) 30 31#define DMA_STATUS_IDLE 0x0 32#define DMA_STATUS_DESC_READ 0x1 33#define DMA_STATUS_WAIT 0x2 34#define DMA_STATUS_ACCESS 0x3 35#define DMA_STATUS_BITS_PER_CH 2 36#define DMA_STATUS_MASK_BITS 0x3 37#define DMA_STATUS_SHIFT_BITS 16 38#define DMA_STATUS_IRQ(x) (0x1 << (x)) 39#define DMA_STATUS0_ERR(x) (0x1 << ((x) + 8)) 40#define DMA_STATUS2_ERR(x) (0x1 << (x)) 41 42#define DMA_DESC_WIDTH_SHIFT_BITS 12 43#define DMA_DESC_WIDTH_1_BYTE (0x3 << DMA_DESC_WIDTH_SHIFT_BITS) 44#define DMA_DESC_WIDTH_2_BYTES (0x2 << DMA_DESC_WIDTH_SHIFT_BITS) 45#define DMA_DESC_WIDTH_4_BYTES (0x0 << DMA_DESC_WIDTH_SHIFT_BITS) 46#define DMA_DESC_MAX_COUNT_1_BYTE 0x3FF 47#define DMA_DESC_MAX_COUNT_2_BYTES 0x3FF 48#define DMA_DESC_MAX_COUNT_4_BYTES 0x7FF 49#define DMA_DESC_END_WITHOUT_IRQ 0x0 50#define DMA_DESC_END_WITH_IRQ 0x1 51#define DMA_DESC_FOLLOW_WITHOUT_IRQ 0x2 52#define DMA_DESC_FOLLOW_WITH_IRQ 0x3 53 54#define MAX_CHAN_NR 12 55 56#define DMA_MASK_CTL0_MODE 0x33333333 57#define DMA_MASK_CTL2_MODE 0x00003333 58 59static unsigned int init_nr_desc_per_channel = 64; 60module_param(init_nr_desc_per_channel, uint, 0644); 61MODULE_PARM_DESC(init_nr_desc_per_channel, 62 "initial descriptors per channel (default: 64)"); 63 64struct pch_dma_desc_regs { 65 u32 dev_addr; 66 u32 mem_addr; 67 u32 size; 68 u32 next; 69}; 70 71struct pch_dma_regs { 72 u32 dma_ctl0; 73 u32 dma_ctl1; 74 u32 dma_ctl2; 75 u32 dma_ctl3; 76 u32 dma_sts0; 77 u32 dma_sts1; 78 u32 dma_sts2; 79 u32 reserved3; 80 struct pch_dma_desc_regs desc[MAX_CHAN_NR]; 81}; 82 83struct pch_dma_desc { 84 struct pch_dma_desc_regs regs; 85 struct dma_async_tx_descriptor txd; 86 struct list_head desc_node; 87 struct list_head tx_list; 88}; 89 90struct pch_dma_chan { 91 struct dma_chan chan; 92 void __iomem *membase; 93 enum dma_transfer_direction dir; 94 struct tasklet_struct tasklet; 95 unsigned long err_status; 96 97 spinlock_t lock; 98 99 struct list_head active_list; 100 struct list_head queue; 101 struct list_head free_list; 102 unsigned int descs_allocated; 103}; 104 105#define PDC_DEV_ADDR 0x00 106#define PDC_MEM_ADDR 0x04 107#define PDC_SIZE 0x08 108#define PDC_NEXT 0x0C 109 110#define channel_readl(pdc, name) \ 111 readl((pdc)->membase + PDC_##name) 112#define channel_writel(pdc, name, val) \ 113 writel((val), (pdc)->membase + PDC_##name) 114 115struct pch_dma { 116 struct dma_device dma; 117 void __iomem *membase; 118 struct dma_pool *pool; 119 struct pch_dma_regs regs; 120 struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR]; 121 struct pch_dma_chan channels[MAX_CHAN_NR]; 122}; 123 124#define PCH_DMA_CTL0 0x00 125#define PCH_DMA_CTL1 0x04 126#define PCH_DMA_CTL2 0x08 127#define PCH_DMA_CTL3 0x0C 128#define PCH_DMA_STS0 0x10 129#define PCH_DMA_STS1 0x14 130#define PCH_DMA_STS2 0x18 131 132#define dma_readl(pd, name) \ 133 readl((pd)->membase + PCH_DMA_##name) 134#define dma_writel(pd, name, val) \ 135 writel((val), (pd)->membase + PCH_DMA_##name) 136 137static inline 138struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd) 139{ 140 return container_of(txd, struct pch_dma_desc, txd); 141} 142 143static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan) 144{ 145 return container_of(chan, struct pch_dma_chan, chan); 146} 147 148static inline struct pch_dma *to_pd(struct dma_device *ddev) 149{ 150 return container_of(ddev, struct pch_dma, dma); 151} 152 153static inline struct device *chan2dev(struct dma_chan *chan) 154{ 155 return &chan->dev->device; 156} 157 158static inline struct device *chan2parent(struct dma_chan *chan) 159{ 160 return chan->dev->device.parent; 161} 162 163static inline 164struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan) 165{ 166 return list_first_entry(&pd_chan->active_list, 167 struct pch_dma_desc, desc_node); 168} 169 170static inline 171struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan) 172{ 173 return list_first_entry(&pd_chan->queue, 174 struct pch_dma_desc, desc_node); 175} 176 177static void pdc_enable_irq(struct dma_chan *chan, int enable) 178{ 179 struct pch_dma *pd = to_pd(chan->device); 180 u32 val; 181 int pos; 182 183 if (chan->chan_id < 8) 184 pos = chan->chan_id; 185 else 186 pos = chan->chan_id + 8; 187 188 val = dma_readl(pd, CTL2); 189 190 if (enable) 191 val |= 0x1 << pos; 192 else 193 val &= ~(0x1 << pos); 194 195 dma_writel(pd, CTL2, val); 196 197 dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n", 198 chan->chan_id, val); 199} 200 201static void pdc_set_dir(struct dma_chan *chan) 202{ 203 struct pch_dma_chan *pd_chan = to_pd_chan(chan); 204 struct pch_dma *pd = to_pd(chan->device); 205 u32 val; 206 u32 mask_mode; 207 u32 mask_ctl; 208 209 if (chan->chan_id < 8) { 210 val = dma_readl(pd, CTL0); 211 212 mask_mode = DMA_CTL0_MODE_MASK_BITS << 213 (DMA_CTL0_BITS_PER_CH * chan->chan_id); 214 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS << 215 (DMA_CTL0_BITS_PER_CH * chan->chan_id)); 216 val &= mask_mode; 217 if (pd_chan->dir == DMA_MEM_TO_DEV) 218 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id + 219 DMA_CTL0_DIR_SHIFT_BITS); 220 else 221 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id + 222 DMA_CTL0_DIR_SHIFT_BITS)); 223 224 val |= mask_ctl; 225 dma_writel(pd, CTL0, val); 226 } else { 227 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */ 228 val = dma_readl(pd, CTL3); 229 230 mask_mode = DMA_CTL0_MODE_MASK_BITS << 231 (DMA_CTL0_BITS_PER_CH * ch); 232 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS << 233 (DMA_CTL0_BITS_PER_CH * ch)); 234 val &= mask_mode; 235 if (pd_chan->dir == DMA_MEM_TO_DEV) 236 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * ch + 237 DMA_CTL0_DIR_SHIFT_BITS); 238 else 239 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * ch + 240 DMA_CTL0_DIR_SHIFT_BITS)); 241 val |= mask_ctl; 242 dma_writel(pd, CTL3, val); 243 } 244 245 dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n", 246 chan->chan_id, val); 247} 248 249static void pdc_set_mode(struct dma_chan *chan, u32 mode) 250{ 251 struct pch_dma *pd = to_pd(chan->device); 252 u32 val; 253 u32 mask_ctl; 254 u32 mask_dir; 255 256 if (chan->chan_id < 8) { 257 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS << 258 (DMA_CTL0_BITS_PER_CH * chan->chan_id)); 259 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +\ 260 DMA_CTL0_DIR_SHIFT_BITS); 261 val = dma_readl(pd, CTL0); 262 val &= mask_dir; 263 val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id); 264 val |= mask_ctl; 265 dma_writel(pd, CTL0, val); 266 } else { 267 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */ 268 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS << 269 (DMA_CTL0_BITS_PER_CH * ch)); 270 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * ch +\ 271 DMA_CTL0_DIR_SHIFT_BITS); 272 val = dma_readl(pd, CTL3); 273 val &= mask_dir; 274 val |= mode << (DMA_CTL0_BITS_PER_CH * ch); 275 val |= mask_ctl; 276 dma_writel(pd, CTL3, val); 277 } 278 279 dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n", 280 chan->chan_id, val); 281} 282 283static u32 pdc_get_status0(struct pch_dma_chan *pd_chan) 284{ 285 struct pch_dma *pd = to_pd(pd_chan->chan.device); 286 u32 val; 287 288 val = dma_readl(pd, STS0); 289 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS + 290 DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id)); 291} 292 293static u32 pdc_get_status2(struct pch_dma_chan *pd_chan) 294{ 295 struct pch_dma *pd = to_pd(pd_chan->chan.device); 296 u32 val; 297 298 val = dma_readl(pd, STS2); 299 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS + 300 DMA_STATUS_BITS_PER_CH * (pd_chan->chan.chan_id - 8))); 301} 302 303static bool pdc_is_idle(struct pch_dma_chan *pd_chan) 304{ 305 u32 sts; 306 307 if (pd_chan->chan.chan_id < 8) 308 sts = pdc_get_status0(pd_chan); 309 else 310 sts = pdc_get_status2(pd_chan); 311 312 313 if (sts == DMA_STATUS_IDLE) 314 return true; 315 else 316 return false; 317} 318 319static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc) 320{ 321 if (!pdc_is_idle(pd_chan)) { 322 dev_err(chan2dev(&pd_chan->chan), 323 "BUG: Attempt to start non-idle channel\n"); 324 return; 325 } 326 327 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n", 328 pd_chan->chan.chan_id, desc->regs.dev_addr); 329 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n", 330 pd_chan->chan.chan_id, desc->regs.mem_addr); 331 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n", 332 pd_chan->chan.chan_id, desc->regs.size); 333 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n", 334 pd_chan->chan.chan_id, desc->regs.next); 335 336 if (list_empty(&desc->tx_list)) { 337 channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr); 338 channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr); 339 channel_writel(pd_chan, SIZE, desc->regs.size); 340 channel_writel(pd_chan, NEXT, desc->regs.next); 341 pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT); 342 } else { 343 channel_writel(pd_chan, NEXT, desc->txd.phys); 344 pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG); 345 } 346} 347 348static void pdc_chain_complete(struct pch_dma_chan *pd_chan, 349 struct pch_dma_desc *desc) 350{ 351 struct dma_async_tx_descriptor *txd = &desc->txd; 352 struct dmaengine_desc_callback cb; 353 354 dmaengine_desc_get_callback(txd, &cb); 355 list_splice_init(&desc->tx_list, &pd_chan->free_list); 356 list_move(&desc->desc_node, &pd_chan->free_list); 357 358 dmaengine_desc_callback_invoke(&cb, NULL); 359} 360 361static void pdc_complete_all(struct pch_dma_chan *pd_chan) 362{ 363 struct pch_dma_desc *desc, *_d; 364 LIST_HEAD(list); 365 366 BUG_ON(!pdc_is_idle(pd_chan)); 367 368 if (!list_empty(&pd_chan->queue)) 369 pdc_dostart(pd_chan, pdc_first_queued(pd_chan)); 370 371 list_splice_init(&pd_chan->active_list, &list); 372 list_splice_init(&pd_chan->queue, &pd_chan->active_list); 373 374 list_for_each_entry_safe(desc, _d, &list, desc_node) 375 pdc_chain_complete(pd_chan, desc); 376} 377 378static void pdc_handle_error(struct pch_dma_chan *pd_chan) 379{ 380 struct pch_dma_desc *bad_desc; 381 382 bad_desc = pdc_first_active(pd_chan); 383 list_del(&bad_desc->desc_node); 384 385 list_splice_init(&pd_chan->queue, pd_chan->active_list.prev); 386 387 if (!list_empty(&pd_chan->active_list)) 388 pdc_dostart(pd_chan, pdc_first_active(pd_chan)); 389 390 dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n"); 391 dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n", 392 bad_desc->txd.cookie); 393 394 pdc_chain_complete(pd_chan, bad_desc); 395} 396 397static void pdc_advance_work(struct pch_dma_chan *pd_chan) 398{ 399 if (list_empty(&pd_chan->active_list) || 400 list_is_singular(&pd_chan->active_list)) { 401 pdc_complete_all(pd_chan); 402 } else { 403 pdc_chain_complete(pd_chan, pdc_first_active(pd_chan)); 404 pdc_dostart(pd_chan, pdc_first_active(pd_chan)); 405 } 406} 407 408static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd) 409{ 410 struct pch_dma_desc *desc = to_pd_desc(txd); 411 struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan); 412 413 spin_lock(&pd_chan->lock); 414 415 if (list_empty(&pd_chan->active_list)) { 416 list_add_tail(&desc->desc_node, &pd_chan->active_list); 417 pdc_dostart(pd_chan, desc); 418 } else { 419 list_add_tail(&desc->desc_node, &pd_chan->queue); 420 } 421 422 spin_unlock(&pd_chan->lock); 423 return 0; 424} 425 426static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags) 427{ 428 struct pch_dma_desc *desc = NULL; 429 struct pch_dma *pd = to_pd(chan->device); 430 dma_addr_t addr; 431 432 desc = dma_pool_zalloc(pd->pool, flags, &addr); 433 if (desc) { 434 INIT_LIST_HEAD(&desc->tx_list); 435 dma_async_tx_descriptor_init(&desc->txd, chan); 436 desc->txd.tx_submit = pd_tx_submit; 437 desc->txd.flags = DMA_CTRL_ACK; 438 desc->txd.phys = addr; 439 } 440 441 return desc; 442} 443 444static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan) 445{ 446 struct pch_dma_desc *desc, *_d; 447 struct pch_dma_desc *ret = NULL; 448 int i = 0; 449 450 spin_lock(&pd_chan->lock); 451 list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) { 452 i++; 453 if (async_tx_test_ack(&desc->txd)) { 454 list_del(&desc->desc_node); 455 ret = desc; 456 break; 457 } 458 dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc); 459 } 460 spin_unlock(&pd_chan->lock); 461 dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i); 462 463 if (!ret) { 464 ret = pdc_alloc_desc(&pd_chan->chan, GFP_ATOMIC); 465 if (ret) { 466 spin_lock(&pd_chan->lock); 467 pd_chan->descs_allocated++; 468 spin_unlock(&pd_chan->lock); 469 } else { 470 dev_err(chan2dev(&pd_chan->chan), 471 "failed to alloc desc\n"); 472 } 473 } 474 475 return ret; 476} 477 478static void pdc_desc_put(struct pch_dma_chan *pd_chan, 479 struct pch_dma_desc *desc) 480{ 481 if (desc) { 482 spin_lock(&pd_chan->lock); 483 list_splice_init(&desc->tx_list, &pd_chan->free_list); 484 list_add(&desc->desc_node, &pd_chan->free_list); 485 spin_unlock(&pd_chan->lock); 486 } 487} 488 489static int pd_alloc_chan_resources(struct dma_chan *chan) 490{ 491 struct pch_dma_chan *pd_chan = to_pd_chan(chan); 492 struct pch_dma_desc *desc; 493 LIST_HEAD(tmp_list); 494 int i; 495 496 if (!pdc_is_idle(pd_chan)) { 497 dev_dbg(chan2dev(chan), "DMA channel not idle ?\n"); 498 return -EIO; 499 } 500 501 if (!list_empty(&pd_chan->free_list)) 502 return pd_chan->descs_allocated; 503 504 for (i = 0; i < init_nr_desc_per_channel; i++) { 505 desc = pdc_alloc_desc(chan, GFP_KERNEL); 506 507 if (!desc) { 508 dev_warn(chan2dev(chan), 509 "Only allocated %d initial descriptors\n", i); 510 break; 511 } 512 513 list_add_tail(&desc->desc_node, &tmp_list); 514 } 515 516 spin_lock_irq(&pd_chan->lock); 517 list_splice(&tmp_list, &pd_chan->free_list); 518 pd_chan->descs_allocated = i; 519 dma_cookie_init(chan); 520 spin_unlock_irq(&pd_chan->lock); 521 522 pdc_enable_irq(chan, 1); 523 524 return pd_chan->descs_allocated; 525} 526 527static void pd_free_chan_resources(struct dma_chan *chan) 528{ 529 struct pch_dma_chan *pd_chan = to_pd_chan(chan); 530 struct pch_dma *pd = to_pd(chan->device); 531 struct pch_dma_desc *desc, *_d; 532 LIST_HEAD(tmp_list); 533 534 BUG_ON(!pdc_is_idle(pd_chan)); 535 BUG_ON(!list_empty(&pd_chan->active_list)); 536 BUG_ON(!list_empty(&pd_chan->queue)); 537 538 spin_lock_irq(&pd_chan->lock); 539 list_splice_init(&pd_chan->free_list, &tmp_list); 540 pd_chan->descs_allocated = 0; 541 spin_unlock_irq(&pd_chan->lock); 542 543 list_for_each_entry_safe(desc, _d, &tmp_list, desc_node) 544 dma_pool_free(pd->pool, desc, desc->txd.phys); 545 546 pdc_enable_irq(chan, 0); 547} 548 549static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie, 550 struct dma_tx_state *txstate) 551{ 552 return dma_cookie_status(chan, cookie, txstate); 553} 554 555static void pd_issue_pending(struct dma_chan *chan) 556{ 557 struct pch_dma_chan *pd_chan = to_pd_chan(chan); 558 559 if (pdc_is_idle(pd_chan)) { 560 spin_lock(&pd_chan->lock); 561 pdc_advance_work(pd_chan); 562 spin_unlock(&pd_chan->lock); 563 } 564} 565 566static struct dma_async_tx_descriptor *pd_prep_slave_sg(struct dma_chan *chan, 567 struct scatterlist *sgl, unsigned int sg_len, 568 enum dma_transfer_direction direction, unsigned long flags, 569 void *context) 570{ 571 struct pch_dma_chan *pd_chan = to_pd_chan(chan); 572 struct pch_dma_slave *pd_slave = chan->private; 573 struct pch_dma_desc *first = NULL; 574 struct pch_dma_desc *prev = NULL; 575 struct pch_dma_desc *desc = NULL; 576 struct scatterlist *sg; 577 dma_addr_t reg; 578 int i; 579 580 if (unlikely(!sg_len)) { 581 dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n"); 582 return NULL; 583 } 584 585 if (direction == DMA_DEV_TO_MEM) 586 reg = pd_slave->rx_reg; 587 else if (direction == DMA_MEM_TO_DEV) 588 reg = pd_slave->tx_reg; 589 else 590 return NULL; 591 592 pd_chan->dir = direction; 593 pdc_set_dir(chan); 594 595 for_each_sg(sgl, sg, sg_len, i) { 596 desc = pdc_desc_get(pd_chan); 597 598 if (!desc) 599 goto err_desc_get; 600 601 desc->regs.dev_addr = reg; 602 desc->regs.mem_addr = sg_dma_address(sg); 603 desc->regs.size = sg_dma_len(sg); 604 desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ; 605 606 switch (pd_slave->width) { 607 case PCH_DMA_WIDTH_1_BYTE: 608 if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE) 609 goto err_desc_get; 610 desc->regs.size |= DMA_DESC_WIDTH_1_BYTE; 611 break; 612 case PCH_DMA_WIDTH_2_BYTES: 613 if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES) 614 goto err_desc_get; 615 desc->regs.size |= DMA_DESC_WIDTH_2_BYTES; 616 break; 617 case PCH_DMA_WIDTH_4_BYTES: 618 if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES) 619 goto err_desc_get; 620 desc->regs.size |= DMA_DESC_WIDTH_4_BYTES; 621 break; 622 default: 623 goto err_desc_get; 624 } 625 626 if (!first) { 627 first = desc; 628 } else { 629 prev->regs.next |= desc->txd.phys; 630 list_add_tail(&desc->desc_node, &first->tx_list); 631 } 632 633 prev = desc; 634 } 635 636 if (flags & DMA_PREP_INTERRUPT) 637 desc->regs.next = DMA_DESC_END_WITH_IRQ; 638 else 639 desc->regs.next = DMA_DESC_END_WITHOUT_IRQ; 640 641 first->txd.cookie = -EBUSY; 642 desc->txd.flags = flags; 643 644 return &first->txd; 645 646err_desc_get: 647 dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n"); 648 pdc_desc_put(pd_chan, first); 649 return NULL; 650} 651 652static int pd_device_terminate_all(struct dma_chan *chan) 653{ 654 struct pch_dma_chan *pd_chan = to_pd_chan(chan); 655 struct pch_dma_desc *desc, *_d; 656 LIST_HEAD(list); 657 658 spin_lock_irq(&pd_chan->lock); 659 660 pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE); 661 662 list_splice_init(&pd_chan->active_list, &list); 663 list_splice_init(&pd_chan->queue, &list); 664 665 list_for_each_entry_safe(desc, _d, &list, desc_node) 666 pdc_chain_complete(pd_chan, desc); 667 668 spin_unlock_irq(&pd_chan->lock); 669 670 return 0; 671} 672 673static void pdc_tasklet(struct tasklet_struct *t) 674{ 675 struct pch_dma_chan *pd_chan = from_tasklet(pd_chan, t, tasklet); 676 unsigned long flags; 677 678 if (!pdc_is_idle(pd_chan)) { 679 dev_err(chan2dev(&pd_chan->chan), 680 "BUG: handle non-idle channel in tasklet\n"); 681 return; 682 } 683 684 spin_lock_irqsave(&pd_chan->lock, flags); 685 if (test_and_clear_bit(0, &pd_chan->err_status)) 686 pdc_handle_error(pd_chan); 687 else 688 pdc_advance_work(pd_chan); 689 spin_unlock_irqrestore(&pd_chan->lock, flags); 690} 691 692static irqreturn_t pd_irq(int irq, void *devid) 693{ 694 struct pch_dma *pd = (struct pch_dma *)devid; 695 struct pch_dma_chan *pd_chan; 696 u32 sts0; 697 u32 sts2; 698 int i; 699 int ret0 = IRQ_NONE; 700 int ret2 = IRQ_NONE; 701 702 sts0 = dma_readl(pd, STS0); 703 sts2 = dma_readl(pd, STS2); 704 705 dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0); 706 707 for (i = 0; i < pd->dma.chancnt; i++) { 708 pd_chan = &pd->channels[i]; 709 710 if (i < 8) { 711 if (sts0 & DMA_STATUS_IRQ(i)) { 712 if (sts0 & DMA_STATUS0_ERR(i)) 713 set_bit(0, &pd_chan->err_status); 714 715 tasklet_schedule(&pd_chan->tasklet); 716 ret0 = IRQ_HANDLED; 717 } 718 } else { 719 if (sts2 & DMA_STATUS_IRQ(i - 8)) { 720 if (sts2 & DMA_STATUS2_ERR(i)) 721 set_bit(0, &pd_chan->err_status); 722 723 tasklet_schedule(&pd_chan->tasklet); 724 ret2 = IRQ_HANDLED; 725 } 726 } 727 } 728 729 /* clear interrupt bits in status register */ 730 if (ret0) 731 dma_writel(pd, STS0, sts0); 732 if (ret2) 733 dma_writel(pd, STS2, sts2); 734 735 return ret0 | ret2; 736} 737 738static void __maybe_unused pch_dma_save_regs(struct pch_dma *pd) 739{ 740 struct pch_dma_chan *pd_chan; 741 struct dma_chan *chan, *_c; 742 int i = 0; 743 744 pd->regs.dma_ctl0 = dma_readl(pd, CTL0); 745 pd->regs.dma_ctl1 = dma_readl(pd, CTL1); 746 pd->regs.dma_ctl2 = dma_readl(pd, CTL2); 747 pd->regs.dma_ctl3 = dma_readl(pd, CTL3); 748 749 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) { 750 pd_chan = to_pd_chan(chan); 751 752 pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR); 753 pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR); 754 pd->ch_regs[i].size = channel_readl(pd_chan, SIZE); 755 pd->ch_regs[i].next = channel_readl(pd_chan, NEXT); 756 757 i++; 758 } 759} 760 761static void __maybe_unused pch_dma_restore_regs(struct pch_dma *pd) 762{ 763 struct pch_dma_chan *pd_chan; 764 struct dma_chan *chan, *_c; 765 int i = 0; 766 767 dma_writel(pd, CTL0, pd->regs.dma_ctl0); 768 dma_writel(pd, CTL1, pd->regs.dma_ctl1); 769 dma_writel(pd, CTL2, pd->regs.dma_ctl2); 770 dma_writel(pd, CTL3, pd->regs.dma_ctl3); 771 772 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) { 773 pd_chan = to_pd_chan(chan); 774 775 channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr); 776 channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr); 777 channel_writel(pd_chan, SIZE, pd->ch_regs[i].size); 778 channel_writel(pd_chan, NEXT, pd->ch_regs[i].next); 779 780 i++; 781 } 782} 783 784static int __maybe_unused pch_dma_suspend(struct device *dev) 785{ 786 struct pch_dma *pd = dev_get_drvdata(dev); 787 788 if (pd) 789 pch_dma_save_regs(pd); 790 791 return 0; 792} 793 794static int __maybe_unused pch_dma_resume(struct device *dev) 795{ 796 struct pch_dma *pd = dev_get_drvdata(dev); 797 798 if (pd) 799 pch_dma_restore_regs(pd); 800 801 return 0; 802} 803 804static int pch_dma_probe(struct pci_dev *pdev, 805 const struct pci_device_id *id) 806{ 807 struct pch_dma *pd; 808 struct pch_dma_regs *regs; 809 unsigned int nr_channels; 810 int err; 811 int i; 812 813 nr_channels = id->driver_data; 814 pd = kzalloc(sizeof(*pd), GFP_KERNEL); 815 if (!pd) 816 return -ENOMEM; 817 818 pci_set_drvdata(pdev, pd); 819 820 err = pci_enable_device(pdev); 821 if (err) { 822 dev_err(&pdev->dev, "Cannot enable PCI device\n"); 823 goto err_free_mem; 824 } 825 826 if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) { 827 dev_err(&pdev->dev, "Cannot find proper base address\n"); 828 err = -ENODEV; 829 goto err_disable_pdev; 830 } 831 832 err = pci_request_regions(pdev, DRV_NAME); 833 if (err) { 834 dev_err(&pdev->dev, "Cannot obtain PCI resources\n"); 835 goto err_disable_pdev; 836 } 837 838 err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)); 839 if (err) { 840 dev_err(&pdev->dev, "Cannot set proper DMA config\n"); 841 goto err_free_res; 842 } 843 844 regs = pd->membase = pci_iomap(pdev, 1, 0); 845 if (!pd->membase) { 846 dev_err(&pdev->dev, "Cannot map MMIO registers\n"); 847 err = -ENOMEM; 848 goto err_free_res; 849 } 850 851 pci_set_master(pdev); 852 pd->dma.dev = &pdev->dev; 853 854 err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd); 855 if (err) { 856 dev_err(&pdev->dev, "Failed to request IRQ\n"); 857 goto err_iounmap; 858 } 859 860 pd->pool = dma_pool_create("pch_dma_desc_pool", &pdev->dev, 861 sizeof(struct pch_dma_desc), 4, 0); 862 if (!pd->pool) { 863 dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n"); 864 err = -ENOMEM; 865 goto err_free_irq; 866 } 867 868 869 INIT_LIST_HEAD(&pd->dma.channels); 870 871 for (i = 0; i < nr_channels; i++) { 872 struct pch_dma_chan *pd_chan = &pd->channels[i]; 873 874 pd_chan->chan.device = &pd->dma; 875 dma_cookie_init(&pd_chan->chan); 876 877 pd_chan->membase = ®s->desc[i]; 878 879 spin_lock_init(&pd_chan->lock); 880 881 INIT_LIST_HEAD(&pd_chan->active_list); 882 INIT_LIST_HEAD(&pd_chan->queue); 883 INIT_LIST_HEAD(&pd_chan->free_list); 884 885 tasklet_setup(&pd_chan->tasklet, pdc_tasklet); 886 list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels); 887 } 888 889 dma_cap_zero(pd->dma.cap_mask); 890 dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask); 891 dma_cap_set(DMA_SLAVE, pd->dma.cap_mask); 892 893 pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources; 894 pd->dma.device_free_chan_resources = pd_free_chan_resources; 895 pd->dma.device_tx_status = pd_tx_status; 896 pd->dma.device_issue_pending = pd_issue_pending; 897 pd->dma.device_prep_slave_sg = pd_prep_slave_sg; 898 pd->dma.device_terminate_all = pd_device_terminate_all; 899 900 err = dma_async_device_register(&pd->dma); 901 if (err) { 902 dev_err(&pdev->dev, "Failed to register DMA device\n"); 903 goto err_free_pool; 904 } 905 906 return 0; 907 908err_free_pool: 909 dma_pool_destroy(pd->pool); 910err_free_irq: 911 free_irq(pdev->irq, pd); 912err_iounmap: 913 pci_iounmap(pdev, pd->membase); 914err_free_res: 915 pci_release_regions(pdev); 916err_disable_pdev: 917 pci_disable_device(pdev); 918err_free_mem: 919 kfree(pd); 920 return err; 921} 922 923static void pch_dma_remove(struct pci_dev *pdev) 924{ 925 struct pch_dma *pd = pci_get_drvdata(pdev); 926 struct pch_dma_chan *pd_chan; 927 struct dma_chan *chan, *_c; 928 929 if (pd) { 930 dma_async_device_unregister(&pd->dma); 931 932 free_irq(pdev->irq, pd); 933 934 list_for_each_entry_safe(chan, _c, &pd->dma.channels, 935 device_node) { 936 pd_chan = to_pd_chan(chan); 937 938 tasklet_kill(&pd_chan->tasklet); 939 } 940 941 dma_pool_destroy(pd->pool); 942 pci_iounmap(pdev, pd->membase); 943 pci_release_regions(pdev); 944 pci_disable_device(pdev); 945 kfree(pd); 946 } 947} 948 949/* PCI Device ID of DMA device */ 950#define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH 0x8810 951#define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH 0x8815 952#define PCI_DEVICE_ID_ML7213_DMA1_8CH 0x8026 953#define PCI_DEVICE_ID_ML7213_DMA2_8CH 0x802B 954#define PCI_DEVICE_ID_ML7213_DMA3_4CH 0x8034 955#define PCI_DEVICE_ID_ML7213_DMA4_12CH 0x8032 956#define PCI_DEVICE_ID_ML7223_DMA1_4CH 0x800B 957#define PCI_DEVICE_ID_ML7223_DMA2_4CH 0x800E 958#define PCI_DEVICE_ID_ML7223_DMA3_4CH 0x8017 959#define PCI_DEVICE_ID_ML7223_DMA4_4CH 0x803B 960#define PCI_DEVICE_ID_ML7831_DMA1_8CH 0x8810 961#define PCI_DEVICE_ID_ML7831_DMA2_4CH 0x8815 962 963static const struct pci_device_id pch_dma_id_table[] = { 964 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 }, 965 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 }, 966 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */ 967 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */ 968 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */ 969 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA4_12CH), 12}, /* I2S */ 970 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA1_4CH), 4}, /* UART */ 971 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA2_4CH), 4}, /* Video SPI */ 972 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA3_4CH), 4}, /* Security */ 973 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA4_4CH), 4}, /* FPGA */ 974 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA1_8CH), 8}, /* UART */ 975 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA2_4CH), 4}, /* SPI */ 976 { 0, }, 977}; 978 979static SIMPLE_DEV_PM_OPS(pch_dma_pm_ops, pch_dma_suspend, pch_dma_resume); 980 981static struct pci_driver pch_dma_driver = { 982 .name = DRV_NAME, 983 .id_table = pch_dma_id_table, 984 .probe = pch_dma_probe, 985 .remove = pch_dma_remove, 986 .driver.pm = &pch_dma_pm_ops, 987}; 988 989module_pci_driver(pch_dma_driver); 990 991MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH " 992 "DMA controller driver"); 993MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>"); 994MODULE_LICENSE("GPL v2"); 995MODULE_DEVICE_TABLE(pci, pch_dma_id_table); 996