1 /* 2 * Copyright (C) 2013-2014 Allwinner Tech Co., Ltd 3 * Author: Sugar <shuge@allwinnertech.com> 4 * 5 * Copyright (C) 2014 Maxime Ripard 6 * Maxime Ripard <maxime.ripard@free-electrons.com> 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 as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 */ 13 14 #include <linux/clk.h> 15 #include <linux/delay.h> 16 #include <linux/dmaengine.h> 17 #include <linux/dmapool.h> 18 #include <linux/interrupt.h> 19 #include <linux/module.h> 20 #include <linux/of_dma.h> 21 #include <linux/of_device.h> 22 #include <linux/platform_device.h> 23 #include <linux/reset.h> 24 #include <linux/slab.h> 25 #include <linux/types.h> 26 27 #include "virt-dma.h" 28 29 /* 30 * Common registers 31 */ 32 #define DMA_IRQ_EN(x) ((x) * 0x04) 33 #define DMA_IRQ_HALF BIT(0) 34 #define DMA_IRQ_PKG BIT(1) 35 #define DMA_IRQ_QUEUE BIT(2) 36 37 #define DMA_IRQ_CHAN_NR 8 38 #define DMA_IRQ_CHAN_WIDTH 4 39 40 41 #define DMA_IRQ_STAT(x) ((x) * 0x04 + 0x10) 42 43 #define DMA_STAT 0x30 44 45 /* 46 * sun8i specific registers 47 */ 48 #define SUN8I_DMA_GATE 0x20 49 #define SUN8I_DMA_GATE_ENABLE 0x4 50 51 /* 52 * Channels specific registers 53 */ 54 #define DMA_CHAN_ENABLE 0x00 55 #define DMA_CHAN_ENABLE_START BIT(0) 56 #define DMA_CHAN_ENABLE_STOP 0 57 58 #define DMA_CHAN_PAUSE 0x04 59 #define DMA_CHAN_PAUSE_PAUSE BIT(1) 60 #define DMA_CHAN_PAUSE_RESUME 0 61 62 #define DMA_CHAN_LLI_ADDR 0x08 63 64 #define DMA_CHAN_CUR_CFG 0x0c 65 #define DMA_CHAN_CFG_SRC_DRQ(x) ((x) & 0x1f) 66 #define DMA_CHAN_CFG_SRC_IO_MODE BIT(5) 67 #define DMA_CHAN_CFG_SRC_LINEAR_MODE (0 << 5) 68 #define DMA_CHAN_CFG_SRC_BURST(x) (((x) & 0x3) << 7) 69 #define DMA_CHAN_CFG_SRC_WIDTH(x) (((x) & 0x3) << 9) 70 71 #define DMA_CHAN_CFG_DST_DRQ(x) (DMA_CHAN_CFG_SRC_DRQ(x) << 16) 72 #define DMA_CHAN_CFG_DST_IO_MODE (DMA_CHAN_CFG_SRC_IO_MODE << 16) 73 #define DMA_CHAN_CFG_DST_LINEAR_MODE (DMA_CHAN_CFG_SRC_LINEAR_MODE << 16) 74 #define DMA_CHAN_CFG_DST_BURST(x) (DMA_CHAN_CFG_SRC_BURST(x) << 16) 75 #define DMA_CHAN_CFG_DST_WIDTH(x) (DMA_CHAN_CFG_SRC_WIDTH(x) << 16) 76 77 #define DMA_CHAN_CUR_SRC 0x10 78 79 #define DMA_CHAN_CUR_DST 0x14 80 81 #define DMA_CHAN_CUR_CNT 0x18 82 83 #define DMA_CHAN_CUR_PARA 0x1c 84 85 86 /* 87 * Various hardware related defines 88 */ 89 #define LLI_LAST_ITEM 0xfffff800 90 #define NORMAL_WAIT 8 91 #define DRQ_SDRAM 1 92 93 /* 94 * Hardware channels / ports representation 95 * 96 * The hardware is used in several SoCs, with differing numbers 97 * of channels and endpoints. This structure ties those numbers 98 * to a certain compatible string. 99 */ 100 struct sun6i_dma_config { 101 u32 nr_max_channels; 102 u32 nr_max_requests; 103 u32 nr_max_vchans; 104 }; 105 106 /* 107 * Hardware representation of the LLI 108 * 109 * The hardware will be fed the physical address of this structure, 110 * and read its content in order to start the transfer. 111 */ 112 struct sun6i_dma_lli { 113 u32 cfg; 114 u32 src; 115 u32 dst; 116 u32 len; 117 u32 para; 118 u32 p_lli_next; 119 120 /* 121 * This field is not used by the DMA controller, but will be 122 * used by the CPU to go through the list (mostly for dumping 123 * or freeing it). 124 */ 125 struct sun6i_dma_lli *v_lli_next; 126 }; 127 128 129 struct sun6i_desc { 130 struct virt_dma_desc vd; 131 dma_addr_t p_lli; 132 struct sun6i_dma_lli *v_lli; 133 }; 134 135 struct sun6i_pchan { 136 u32 idx; 137 void __iomem *base; 138 struct sun6i_vchan *vchan; 139 struct sun6i_desc *desc; 140 struct sun6i_desc *done; 141 }; 142 143 struct sun6i_vchan { 144 struct virt_dma_chan vc; 145 struct list_head node; 146 struct dma_slave_config cfg; 147 struct sun6i_pchan *phy; 148 u8 port; 149 }; 150 151 struct sun6i_dma_dev { 152 struct dma_device slave; 153 void __iomem *base; 154 struct clk *clk; 155 int irq; 156 spinlock_t lock; 157 struct reset_control *rstc; 158 struct tasklet_struct task; 159 atomic_t tasklet_shutdown; 160 struct list_head pending; 161 struct dma_pool *pool; 162 struct sun6i_pchan *pchans; 163 struct sun6i_vchan *vchans; 164 const struct sun6i_dma_config *cfg; 165 }; 166 167 static struct device *chan2dev(struct dma_chan *chan) 168 { 169 return &chan->dev->device; 170 } 171 172 static inline struct sun6i_dma_dev *to_sun6i_dma_dev(struct dma_device *d) 173 { 174 return container_of(d, struct sun6i_dma_dev, slave); 175 } 176 177 static inline struct sun6i_vchan *to_sun6i_vchan(struct dma_chan *chan) 178 { 179 return container_of(chan, struct sun6i_vchan, vc.chan); 180 } 181 182 static inline struct sun6i_desc * 183 to_sun6i_desc(struct dma_async_tx_descriptor *tx) 184 { 185 return container_of(tx, struct sun6i_desc, vd.tx); 186 } 187 188 static inline void sun6i_dma_dump_com_regs(struct sun6i_dma_dev *sdev) 189 { 190 dev_dbg(sdev->slave.dev, "Common register:\n" 191 "\tmask0(%04x): 0x%08x\n" 192 "\tmask1(%04x): 0x%08x\n" 193 "\tpend0(%04x): 0x%08x\n" 194 "\tpend1(%04x): 0x%08x\n" 195 "\tstats(%04x): 0x%08x\n", 196 DMA_IRQ_EN(0), readl(sdev->base + DMA_IRQ_EN(0)), 197 DMA_IRQ_EN(1), readl(sdev->base + DMA_IRQ_EN(1)), 198 DMA_IRQ_STAT(0), readl(sdev->base + DMA_IRQ_STAT(0)), 199 DMA_IRQ_STAT(1), readl(sdev->base + DMA_IRQ_STAT(1)), 200 DMA_STAT, readl(sdev->base + DMA_STAT)); 201 } 202 203 static inline void sun6i_dma_dump_chan_regs(struct sun6i_dma_dev *sdev, 204 struct sun6i_pchan *pchan) 205 { 206 phys_addr_t reg = virt_to_phys(pchan->base); 207 208 dev_dbg(sdev->slave.dev, "Chan %d reg: %pa\n" 209 "\t___en(%04x): \t0x%08x\n" 210 "\tpause(%04x): \t0x%08x\n" 211 "\tstart(%04x): \t0x%08x\n" 212 "\t__cfg(%04x): \t0x%08x\n" 213 "\t__src(%04x): \t0x%08x\n" 214 "\t__dst(%04x): \t0x%08x\n" 215 "\tcount(%04x): \t0x%08x\n" 216 "\t_para(%04x): \t0x%08x\n\n", 217 pchan->idx, ®, 218 DMA_CHAN_ENABLE, 219 readl(pchan->base + DMA_CHAN_ENABLE), 220 DMA_CHAN_PAUSE, 221 readl(pchan->base + DMA_CHAN_PAUSE), 222 DMA_CHAN_LLI_ADDR, 223 readl(pchan->base + DMA_CHAN_LLI_ADDR), 224 DMA_CHAN_CUR_CFG, 225 readl(pchan->base + DMA_CHAN_CUR_CFG), 226 DMA_CHAN_CUR_SRC, 227 readl(pchan->base + DMA_CHAN_CUR_SRC), 228 DMA_CHAN_CUR_DST, 229 readl(pchan->base + DMA_CHAN_CUR_DST), 230 DMA_CHAN_CUR_CNT, 231 readl(pchan->base + DMA_CHAN_CUR_CNT), 232 DMA_CHAN_CUR_PARA, 233 readl(pchan->base + DMA_CHAN_CUR_PARA)); 234 } 235 236 static inline s8 convert_burst(u32 maxburst) 237 { 238 switch (maxburst) { 239 case 1: 240 return 0; 241 case 8: 242 return 2; 243 default: 244 return -EINVAL; 245 } 246 } 247 248 static inline s8 convert_buswidth(enum dma_slave_buswidth addr_width) 249 { 250 if ((addr_width < DMA_SLAVE_BUSWIDTH_1_BYTE) || 251 (addr_width > DMA_SLAVE_BUSWIDTH_4_BYTES)) 252 return -EINVAL; 253 254 return addr_width >> 1; 255 } 256 257 static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev, 258 struct sun6i_dma_lli *next, 259 dma_addr_t next_phy, 260 struct sun6i_desc *txd) 261 { 262 if ((!prev && !txd) || !next) 263 return NULL; 264 265 if (!prev) { 266 txd->p_lli = next_phy; 267 txd->v_lli = next; 268 } else { 269 prev->p_lli_next = next_phy; 270 prev->v_lli_next = next; 271 } 272 273 next->p_lli_next = LLI_LAST_ITEM; 274 next->v_lli_next = NULL; 275 276 return next; 277 } 278 279 static inline int sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli, 280 dma_addr_t src, 281 dma_addr_t dst, u32 len, 282 struct dma_slave_config *config) 283 { 284 u8 src_width, dst_width, src_burst, dst_burst; 285 286 if (!config) 287 return -EINVAL; 288 289 src_burst = convert_burst(config->src_maxburst); 290 if (src_burst) 291 return src_burst; 292 293 dst_burst = convert_burst(config->dst_maxburst); 294 if (dst_burst) 295 return dst_burst; 296 297 src_width = convert_buswidth(config->src_addr_width); 298 if (src_width) 299 return src_width; 300 301 dst_width = convert_buswidth(config->dst_addr_width); 302 if (dst_width) 303 return dst_width; 304 305 lli->cfg = DMA_CHAN_CFG_SRC_BURST(src_burst) | 306 DMA_CHAN_CFG_SRC_WIDTH(src_width) | 307 DMA_CHAN_CFG_DST_BURST(dst_burst) | 308 DMA_CHAN_CFG_DST_WIDTH(dst_width); 309 310 lli->src = src; 311 lli->dst = dst; 312 lli->len = len; 313 lli->para = NORMAL_WAIT; 314 315 return 0; 316 } 317 318 static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan, 319 struct sun6i_dma_lli *lli) 320 { 321 phys_addr_t p_lli = virt_to_phys(lli); 322 323 dev_dbg(chan2dev(&vchan->vc.chan), 324 "\n\tdesc: p - %pa v - 0x%p\n" 325 "\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n" 326 "\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n", 327 &p_lli, lli, 328 lli->cfg, lli->src, lli->dst, 329 lli->len, lli->para, lli->p_lli_next); 330 } 331 332 static void sun6i_dma_free_desc(struct virt_dma_desc *vd) 333 { 334 struct sun6i_desc *txd = to_sun6i_desc(&vd->tx); 335 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device); 336 struct sun6i_dma_lli *v_lli, *v_next; 337 dma_addr_t p_lli, p_next; 338 339 if (unlikely(!txd)) 340 return; 341 342 p_lli = txd->p_lli; 343 v_lli = txd->v_lli; 344 345 while (v_lli) { 346 v_next = v_lli->v_lli_next; 347 p_next = v_lli->p_lli_next; 348 349 dma_pool_free(sdev->pool, v_lli, p_lli); 350 351 v_lli = v_next; 352 p_lli = p_next; 353 } 354 355 kfree(txd); 356 } 357 358 static int sun6i_dma_start_desc(struct sun6i_vchan *vchan) 359 { 360 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device); 361 struct virt_dma_desc *desc = vchan_next_desc(&vchan->vc); 362 struct sun6i_pchan *pchan = vchan->phy; 363 u32 irq_val, irq_reg, irq_offset; 364 365 if (!pchan) 366 return -EAGAIN; 367 368 if (!desc) { 369 pchan->desc = NULL; 370 pchan->done = NULL; 371 return -EAGAIN; 372 } 373 374 list_del(&desc->node); 375 376 pchan->desc = to_sun6i_desc(&desc->tx); 377 pchan->done = NULL; 378 379 sun6i_dma_dump_lli(vchan, pchan->desc->v_lli); 380 381 irq_reg = pchan->idx / DMA_IRQ_CHAN_NR; 382 irq_offset = pchan->idx % DMA_IRQ_CHAN_NR; 383 384 irq_val = readl(sdev->base + DMA_IRQ_EN(irq_offset)); 385 irq_val |= DMA_IRQ_QUEUE << (irq_offset * DMA_IRQ_CHAN_WIDTH); 386 writel(irq_val, sdev->base + DMA_IRQ_EN(irq_offset)); 387 388 writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR); 389 writel(DMA_CHAN_ENABLE_START, pchan->base + DMA_CHAN_ENABLE); 390 391 sun6i_dma_dump_com_regs(sdev); 392 sun6i_dma_dump_chan_regs(sdev, pchan); 393 394 return 0; 395 } 396 397 static void sun6i_dma_tasklet(unsigned long data) 398 { 399 struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)data; 400 const struct sun6i_dma_config *cfg = sdev->cfg; 401 struct sun6i_vchan *vchan; 402 struct sun6i_pchan *pchan; 403 unsigned int pchan_alloc = 0; 404 unsigned int pchan_idx; 405 406 list_for_each_entry(vchan, &sdev->slave.channels, vc.chan.device_node) { 407 spin_lock_irq(&vchan->vc.lock); 408 409 pchan = vchan->phy; 410 411 if (pchan && pchan->done) { 412 if (sun6i_dma_start_desc(vchan)) { 413 /* 414 * No current txd associated with this channel 415 */ 416 dev_dbg(sdev->slave.dev, "pchan %u: free\n", 417 pchan->idx); 418 419 /* Mark this channel free */ 420 vchan->phy = NULL; 421 pchan->vchan = NULL; 422 } 423 } 424 spin_unlock_irq(&vchan->vc.lock); 425 } 426 427 spin_lock_irq(&sdev->lock); 428 for (pchan_idx = 0; pchan_idx < cfg->nr_max_channels; pchan_idx++) { 429 pchan = &sdev->pchans[pchan_idx]; 430 431 if (pchan->vchan || list_empty(&sdev->pending)) 432 continue; 433 434 vchan = list_first_entry(&sdev->pending, 435 struct sun6i_vchan, node); 436 437 /* Remove from pending channels */ 438 list_del_init(&vchan->node); 439 pchan_alloc |= BIT(pchan_idx); 440 441 /* Mark this channel allocated */ 442 pchan->vchan = vchan; 443 vchan->phy = pchan; 444 dev_dbg(sdev->slave.dev, "pchan %u: alloc vchan %p\n", 445 pchan->idx, &vchan->vc); 446 } 447 spin_unlock_irq(&sdev->lock); 448 449 for (pchan_idx = 0; pchan_idx < cfg->nr_max_channels; pchan_idx++) { 450 if (!(pchan_alloc & BIT(pchan_idx))) 451 continue; 452 453 pchan = sdev->pchans + pchan_idx; 454 vchan = pchan->vchan; 455 if (vchan) { 456 spin_lock_irq(&vchan->vc.lock); 457 sun6i_dma_start_desc(vchan); 458 spin_unlock_irq(&vchan->vc.lock); 459 } 460 } 461 } 462 463 static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id) 464 { 465 struct sun6i_dma_dev *sdev = dev_id; 466 struct sun6i_vchan *vchan; 467 struct sun6i_pchan *pchan; 468 int i, j, ret = IRQ_NONE; 469 u32 status; 470 471 for (i = 0; i < sdev->cfg->nr_max_channels / DMA_IRQ_CHAN_NR; i++) { 472 status = readl(sdev->base + DMA_IRQ_STAT(i)); 473 if (!status) 474 continue; 475 476 dev_dbg(sdev->slave.dev, "DMA irq status %s: 0x%x\n", 477 i ? "high" : "low", status); 478 479 writel(status, sdev->base + DMA_IRQ_STAT(i)); 480 481 for (j = 0; (j < DMA_IRQ_CHAN_NR) && status; j++) { 482 if (status & DMA_IRQ_QUEUE) { 483 pchan = sdev->pchans + j; 484 vchan = pchan->vchan; 485 486 if (vchan) { 487 spin_lock(&vchan->vc.lock); 488 vchan_cookie_complete(&pchan->desc->vd); 489 pchan->done = pchan->desc; 490 spin_unlock(&vchan->vc.lock); 491 } 492 } 493 494 status = status >> DMA_IRQ_CHAN_WIDTH; 495 } 496 497 if (!atomic_read(&sdev->tasklet_shutdown)) 498 tasklet_schedule(&sdev->task); 499 ret = IRQ_HANDLED; 500 } 501 502 return ret; 503 } 504 505 static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy( 506 struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, 507 size_t len, unsigned long flags) 508 { 509 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); 510 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 511 struct sun6i_dma_lli *v_lli; 512 struct sun6i_desc *txd; 513 dma_addr_t p_lli; 514 s8 burst, width; 515 516 dev_dbg(chan2dev(chan), 517 "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n", 518 __func__, vchan->vc.chan.chan_id, &dest, &src, len, flags); 519 520 if (!len) 521 return NULL; 522 523 txd = kzalloc(sizeof(*txd), GFP_NOWAIT); 524 if (!txd) 525 return NULL; 526 527 v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli); 528 if (!v_lli) { 529 dev_err(sdev->slave.dev, "Failed to alloc lli memory\n"); 530 goto err_txd_free; 531 } 532 533 v_lli->src = src; 534 v_lli->dst = dest; 535 v_lli->len = len; 536 v_lli->para = NORMAL_WAIT; 537 538 burst = convert_burst(8); 539 width = convert_buswidth(DMA_SLAVE_BUSWIDTH_4_BYTES); 540 v_lli->cfg |= DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) | 541 DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) | 542 DMA_CHAN_CFG_DST_LINEAR_MODE | 543 DMA_CHAN_CFG_SRC_LINEAR_MODE | 544 DMA_CHAN_CFG_SRC_BURST(burst) | 545 DMA_CHAN_CFG_SRC_WIDTH(width) | 546 DMA_CHAN_CFG_DST_BURST(burst) | 547 DMA_CHAN_CFG_DST_WIDTH(width); 548 549 sun6i_dma_lli_add(NULL, v_lli, p_lli, txd); 550 551 sun6i_dma_dump_lli(vchan, v_lli); 552 553 return vchan_tx_prep(&vchan->vc, &txd->vd, flags); 554 555 err_txd_free: 556 kfree(txd); 557 return NULL; 558 } 559 560 static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg( 561 struct dma_chan *chan, struct scatterlist *sgl, 562 unsigned int sg_len, enum dma_transfer_direction dir, 563 unsigned long flags, void *context) 564 { 565 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); 566 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 567 struct dma_slave_config *sconfig = &vchan->cfg; 568 struct sun6i_dma_lli *v_lli, *prev = NULL; 569 struct sun6i_desc *txd; 570 struct scatterlist *sg; 571 dma_addr_t p_lli; 572 int i, ret; 573 574 if (!sgl) 575 return NULL; 576 577 if (!is_slave_direction(dir)) { 578 dev_err(chan2dev(chan), "Invalid DMA direction\n"); 579 return NULL; 580 } 581 582 txd = kzalloc(sizeof(*txd), GFP_NOWAIT); 583 if (!txd) 584 return NULL; 585 586 for_each_sg(sgl, sg, sg_len, i) { 587 v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli); 588 if (!v_lli) 589 goto err_lli_free; 590 591 if (dir == DMA_MEM_TO_DEV) { 592 ret = sun6i_dma_cfg_lli(v_lli, sg_dma_address(sg), 593 sconfig->dst_addr, sg_dma_len(sg), 594 sconfig); 595 if (ret) 596 goto err_cur_lli_free; 597 598 v_lli->cfg |= DMA_CHAN_CFG_DST_IO_MODE | 599 DMA_CHAN_CFG_SRC_LINEAR_MODE | 600 DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) | 601 DMA_CHAN_CFG_DST_DRQ(vchan->port); 602 603 dev_dbg(chan2dev(chan), 604 "%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n", 605 __func__, vchan->vc.chan.chan_id, 606 &sconfig->dst_addr, &sg_dma_address(sg), 607 sg_dma_len(sg), flags); 608 609 } else { 610 ret = sun6i_dma_cfg_lli(v_lli, sconfig->src_addr, 611 sg_dma_address(sg), sg_dma_len(sg), 612 sconfig); 613 if (ret) 614 goto err_cur_lli_free; 615 616 v_lli->cfg |= DMA_CHAN_CFG_DST_LINEAR_MODE | 617 DMA_CHAN_CFG_SRC_IO_MODE | 618 DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) | 619 DMA_CHAN_CFG_SRC_DRQ(vchan->port); 620 621 dev_dbg(chan2dev(chan), 622 "%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n", 623 __func__, vchan->vc.chan.chan_id, 624 &sg_dma_address(sg), &sconfig->src_addr, 625 sg_dma_len(sg), flags); 626 } 627 628 prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd); 629 } 630 631 dev_dbg(chan2dev(chan), "First: %pad\n", &txd->p_lli); 632 for (prev = txd->v_lli; prev; prev = prev->v_lli_next) 633 sun6i_dma_dump_lli(vchan, prev); 634 635 return vchan_tx_prep(&vchan->vc, &txd->vd, flags); 636 637 err_cur_lli_free: 638 dma_pool_free(sdev->pool, v_lli, p_lli); 639 err_lli_free: 640 for (prev = txd->v_lli; prev; prev = prev->v_lli_next) 641 dma_pool_free(sdev->pool, prev, virt_to_phys(prev)); 642 kfree(txd); 643 return NULL; 644 } 645 646 static int sun6i_dma_config(struct dma_chan *chan, 647 struct dma_slave_config *config) 648 { 649 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 650 651 memcpy(&vchan->cfg, config, sizeof(*config)); 652 653 return 0; 654 } 655 656 static int sun6i_dma_pause(struct dma_chan *chan) 657 { 658 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); 659 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 660 struct sun6i_pchan *pchan = vchan->phy; 661 662 dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc); 663 664 if (pchan) { 665 writel(DMA_CHAN_PAUSE_PAUSE, 666 pchan->base + DMA_CHAN_PAUSE); 667 } else { 668 spin_lock(&sdev->lock); 669 list_del_init(&vchan->node); 670 spin_unlock(&sdev->lock); 671 } 672 673 return 0; 674 } 675 676 static int sun6i_dma_resume(struct dma_chan *chan) 677 { 678 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); 679 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 680 struct sun6i_pchan *pchan = vchan->phy; 681 unsigned long flags; 682 683 dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc); 684 685 spin_lock_irqsave(&vchan->vc.lock, flags); 686 687 if (pchan) { 688 writel(DMA_CHAN_PAUSE_RESUME, 689 pchan->base + DMA_CHAN_PAUSE); 690 } else if (!list_empty(&vchan->vc.desc_issued)) { 691 spin_lock(&sdev->lock); 692 list_add_tail(&vchan->node, &sdev->pending); 693 spin_unlock(&sdev->lock); 694 } 695 696 spin_unlock_irqrestore(&vchan->vc.lock, flags); 697 698 return 0; 699 } 700 701 static int sun6i_dma_terminate_all(struct dma_chan *chan) 702 { 703 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); 704 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 705 struct sun6i_pchan *pchan = vchan->phy; 706 unsigned long flags; 707 LIST_HEAD(head); 708 709 spin_lock(&sdev->lock); 710 list_del_init(&vchan->node); 711 spin_unlock(&sdev->lock); 712 713 spin_lock_irqsave(&vchan->vc.lock, flags); 714 715 vchan_get_all_descriptors(&vchan->vc, &head); 716 717 if (pchan) { 718 writel(DMA_CHAN_ENABLE_STOP, pchan->base + DMA_CHAN_ENABLE); 719 writel(DMA_CHAN_PAUSE_RESUME, pchan->base + DMA_CHAN_PAUSE); 720 721 vchan->phy = NULL; 722 pchan->vchan = NULL; 723 pchan->desc = NULL; 724 pchan->done = NULL; 725 } 726 727 spin_unlock_irqrestore(&vchan->vc.lock, flags); 728 729 vchan_dma_desc_free_list(&vchan->vc, &head); 730 731 return 0; 732 } 733 734 static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan, 735 dma_cookie_t cookie, 736 struct dma_tx_state *state) 737 { 738 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 739 struct sun6i_pchan *pchan = vchan->phy; 740 struct sun6i_dma_lli *lli; 741 struct virt_dma_desc *vd; 742 struct sun6i_desc *txd; 743 enum dma_status ret; 744 unsigned long flags; 745 size_t bytes = 0; 746 747 ret = dma_cookie_status(chan, cookie, state); 748 if (ret == DMA_COMPLETE) 749 return ret; 750 751 spin_lock_irqsave(&vchan->vc.lock, flags); 752 753 vd = vchan_find_desc(&vchan->vc, cookie); 754 txd = to_sun6i_desc(&vd->tx); 755 756 if (vd) { 757 for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next) 758 bytes += lli->len; 759 } else if (!pchan || !pchan->desc) { 760 bytes = 0; 761 } else { 762 bytes = readl(pchan->base + DMA_CHAN_CUR_CNT); 763 } 764 765 spin_unlock_irqrestore(&vchan->vc.lock, flags); 766 767 dma_set_residue(state, bytes); 768 769 return ret; 770 } 771 772 static void sun6i_dma_issue_pending(struct dma_chan *chan) 773 { 774 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); 775 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 776 unsigned long flags; 777 778 spin_lock_irqsave(&vchan->vc.lock, flags); 779 780 if (vchan_issue_pending(&vchan->vc)) { 781 spin_lock(&sdev->lock); 782 783 if (!vchan->phy && list_empty(&vchan->node)) { 784 list_add_tail(&vchan->node, &sdev->pending); 785 tasklet_schedule(&sdev->task); 786 dev_dbg(chan2dev(chan), "vchan %p: issued\n", 787 &vchan->vc); 788 } 789 790 spin_unlock(&sdev->lock); 791 } else { 792 dev_dbg(chan2dev(chan), "vchan %p: nothing to issue\n", 793 &vchan->vc); 794 } 795 796 spin_unlock_irqrestore(&vchan->vc.lock, flags); 797 } 798 799 static int sun6i_dma_alloc_chan_resources(struct dma_chan *chan) 800 { 801 return 0; 802 } 803 804 static void sun6i_dma_free_chan_resources(struct dma_chan *chan) 805 { 806 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); 807 struct sun6i_vchan *vchan = to_sun6i_vchan(chan); 808 unsigned long flags; 809 810 spin_lock_irqsave(&sdev->lock, flags); 811 list_del_init(&vchan->node); 812 spin_unlock_irqrestore(&sdev->lock, flags); 813 814 vchan_free_chan_resources(&vchan->vc); 815 } 816 817 static struct dma_chan *sun6i_dma_of_xlate(struct of_phandle_args *dma_spec, 818 struct of_dma *ofdma) 819 { 820 struct sun6i_dma_dev *sdev = ofdma->of_dma_data; 821 struct sun6i_vchan *vchan; 822 struct dma_chan *chan; 823 u8 port = dma_spec->args[0]; 824 825 if (port > sdev->cfg->nr_max_requests) 826 return NULL; 827 828 chan = dma_get_any_slave_channel(&sdev->slave); 829 if (!chan) 830 return NULL; 831 832 vchan = to_sun6i_vchan(chan); 833 vchan->port = port; 834 835 return chan; 836 } 837 838 static inline void sun6i_kill_tasklet(struct sun6i_dma_dev *sdev) 839 { 840 /* Disable all interrupts from DMA */ 841 writel(0, sdev->base + DMA_IRQ_EN(0)); 842 writel(0, sdev->base + DMA_IRQ_EN(1)); 843 844 /* Prevent spurious interrupts from scheduling the tasklet */ 845 atomic_inc(&sdev->tasklet_shutdown); 846 847 /* Make sure we won't have any further interrupts */ 848 devm_free_irq(sdev->slave.dev, sdev->irq, sdev); 849 850 /* Actually prevent the tasklet from being scheduled */ 851 tasklet_kill(&sdev->task); 852 } 853 854 static inline void sun6i_dma_free(struct sun6i_dma_dev *sdev) 855 { 856 int i; 857 858 for (i = 0; i < sdev->cfg->nr_max_vchans; i++) { 859 struct sun6i_vchan *vchan = &sdev->vchans[i]; 860 861 list_del(&vchan->vc.chan.device_node); 862 tasklet_kill(&vchan->vc.task); 863 } 864 } 865 866 /* 867 * For A31: 868 * 869 * There's 16 physical channels that can work in parallel. 870 * 871 * However we have 30 different endpoints for our requests. 872 * 873 * Since the channels are able to handle only an unidirectional 874 * transfer, we need to allocate more virtual channels so that 875 * everyone can grab one channel. 876 * 877 * Some devices can't work in both direction (mostly because it 878 * wouldn't make sense), so we have a bit fewer virtual channels than 879 * 2 channels per endpoints. 880 */ 881 882 static struct sun6i_dma_config sun6i_a31_dma_cfg = { 883 .nr_max_channels = 16, 884 .nr_max_requests = 30, 885 .nr_max_vchans = 53, 886 }; 887 888 /* 889 * The A23 only has 8 physical channels, a maximum DRQ port id of 24, 890 * and a total of 37 usable source and destination endpoints. 891 */ 892 893 static struct sun6i_dma_config sun8i_a23_dma_cfg = { 894 .nr_max_channels = 8, 895 .nr_max_requests = 24, 896 .nr_max_vchans = 37, 897 }; 898 899 static struct of_device_id sun6i_dma_match[] = { 900 { .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg }, 901 { .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg }, 902 { /* sentinel */ } 903 }; 904 905 static int sun6i_dma_probe(struct platform_device *pdev) 906 { 907 const struct of_device_id *device; 908 struct sun6i_dma_dev *sdc; 909 struct resource *res; 910 int ret, i; 911 912 sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL); 913 if (!sdc) 914 return -ENOMEM; 915 916 device = of_match_device(sun6i_dma_match, &pdev->dev); 917 if (!device) 918 return -ENODEV; 919 sdc->cfg = device->data; 920 921 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 922 sdc->base = devm_ioremap_resource(&pdev->dev, res); 923 if (IS_ERR(sdc->base)) 924 return PTR_ERR(sdc->base); 925 926 sdc->irq = platform_get_irq(pdev, 0); 927 if (sdc->irq < 0) { 928 dev_err(&pdev->dev, "Cannot claim IRQ\n"); 929 return sdc->irq; 930 } 931 932 sdc->clk = devm_clk_get(&pdev->dev, NULL); 933 if (IS_ERR(sdc->clk)) { 934 dev_err(&pdev->dev, "No clock specified\n"); 935 return PTR_ERR(sdc->clk); 936 } 937 938 sdc->rstc = devm_reset_control_get(&pdev->dev, NULL); 939 if (IS_ERR(sdc->rstc)) { 940 dev_err(&pdev->dev, "No reset controller specified\n"); 941 return PTR_ERR(sdc->rstc); 942 } 943 944 sdc->pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev, 945 sizeof(struct sun6i_dma_lli), 4, 0); 946 if (!sdc->pool) { 947 dev_err(&pdev->dev, "No memory for descriptors dma pool\n"); 948 return -ENOMEM; 949 } 950 951 platform_set_drvdata(pdev, sdc); 952 INIT_LIST_HEAD(&sdc->pending); 953 spin_lock_init(&sdc->lock); 954 955 dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask); 956 dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask); 957 dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask); 958 959 INIT_LIST_HEAD(&sdc->slave.channels); 960 sdc->slave.device_alloc_chan_resources = sun6i_dma_alloc_chan_resources; 961 sdc->slave.device_free_chan_resources = sun6i_dma_free_chan_resources; 962 sdc->slave.device_tx_status = sun6i_dma_tx_status; 963 sdc->slave.device_issue_pending = sun6i_dma_issue_pending; 964 sdc->slave.device_prep_slave_sg = sun6i_dma_prep_slave_sg; 965 sdc->slave.device_prep_dma_memcpy = sun6i_dma_prep_dma_memcpy; 966 sdc->slave.copy_align = 4; 967 sdc->slave.device_config = sun6i_dma_config; 968 sdc->slave.device_pause = sun6i_dma_pause; 969 sdc->slave.device_resume = sun6i_dma_resume; 970 sdc->slave.device_terminate_all = sun6i_dma_terminate_all; 971 sdc->slave.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | 972 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | 973 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); 974 sdc->slave.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | 975 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | 976 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); 977 sdc->slave.directions = BIT(DMA_DEV_TO_MEM) | 978 BIT(DMA_MEM_TO_DEV); 979 sdc->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; 980 sdc->slave.dev = &pdev->dev; 981 982 sdc->pchans = devm_kcalloc(&pdev->dev, sdc->cfg->nr_max_channels, 983 sizeof(struct sun6i_pchan), GFP_KERNEL); 984 if (!sdc->pchans) 985 return -ENOMEM; 986 987 sdc->vchans = devm_kcalloc(&pdev->dev, sdc->cfg->nr_max_vchans, 988 sizeof(struct sun6i_vchan), GFP_KERNEL); 989 if (!sdc->vchans) 990 return -ENOMEM; 991 992 tasklet_init(&sdc->task, sun6i_dma_tasklet, (unsigned long)sdc); 993 994 for (i = 0; i < sdc->cfg->nr_max_channels; i++) { 995 struct sun6i_pchan *pchan = &sdc->pchans[i]; 996 997 pchan->idx = i; 998 pchan->base = sdc->base + 0x100 + i * 0x40; 999 } 1000 1001 for (i = 0; i < sdc->cfg->nr_max_vchans; i++) { 1002 struct sun6i_vchan *vchan = &sdc->vchans[i]; 1003 1004 INIT_LIST_HEAD(&vchan->node); 1005 vchan->vc.desc_free = sun6i_dma_free_desc; 1006 vchan_init(&vchan->vc, &sdc->slave); 1007 } 1008 1009 ret = reset_control_deassert(sdc->rstc); 1010 if (ret) { 1011 dev_err(&pdev->dev, "Couldn't deassert the device from reset\n"); 1012 goto err_chan_free; 1013 } 1014 1015 ret = clk_prepare_enable(sdc->clk); 1016 if (ret) { 1017 dev_err(&pdev->dev, "Couldn't enable the clock\n"); 1018 goto err_reset_assert; 1019 } 1020 1021 ret = devm_request_irq(&pdev->dev, sdc->irq, sun6i_dma_interrupt, 0, 1022 dev_name(&pdev->dev), sdc); 1023 if (ret) { 1024 dev_err(&pdev->dev, "Cannot request IRQ\n"); 1025 goto err_clk_disable; 1026 } 1027 1028 ret = dma_async_device_register(&sdc->slave); 1029 if (ret) { 1030 dev_warn(&pdev->dev, "Failed to register DMA engine device\n"); 1031 goto err_irq_disable; 1032 } 1033 1034 ret = of_dma_controller_register(pdev->dev.of_node, sun6i_dma_of_xlate, 1035 sdc); 1036 if (ret) { 1037 dev_err(&pdev->dev, "of_dma_controller_register failed\n"); 1038 goto err_dma_unregister; 1039 } 1040 1041 /* 1042 * sun8i variant requires us to toggle a dma gating register, 1043 * as seen in Allwinner's SDK. This register is not documented 1044 * in the A23 user manual. 1045 */ 1046 if (of_device_is_compatible(pdev->dev.of_node, 1047 "allwinner,sun8i-a23-dma")) 1048 writel(SUN8I_DMA_GATE_ENABLE, sdc->base + SUN8I_DMA_GATE); 1049 1050 return 0; 1051 1052 err_dma_unregister: 1053 dma_async_device_unregister(&sdc->slave); 1054 err_irq_disable: 1055 sun6i_kill_tasklet(sdc); 1056 err_clk_disable: 1057 clk_disable_unprepare(sdc->clk); 1058 err_reset_assert: 1059 reset_control_assert(sdc->rstc); 1060 err_chan_free: 1061 sun6i_dma_free(sdc); 1062 return ret; 1063 } 1064 1065 static int sun6i_dma_remove(struct platform_device *pdev) 1066 { 1067 struct sun6i_dma_dev *sdc = platform_get_drvdata(pdev); 1068 1069 of_dma_controller_free(pdev->dev.of_node); 1070 dma_async_device_unregister(&sdc->slave); 1071 1072 sun6i_kill_tasklet(sdc); 1073 1074 clk_disable_unprepare(sdc->clk); 1075 reset_control_assert(sdc->rstc); 1076 1077 sun6i_dma_free(sdc); 1078 1079 return 0; 1080 } 1081 1082 static struct platform_driver sun6i_dma_driver = { 1083 .probe = sun6i_dma_probe, 1084 .remove = sun6i_dma_remove, 1085 .driver = { 1086 .name = "sun6i-dma", 1087 .of_match_table = sun6i_dma_match, 1088 }, 1089 }; 1090 module_platform_driver(sun6i_dma_driver); 1091 1092 MODULE_DESCRIPTION("Allwinner A31 DMA Controller Driver"); 1093 MODULE_AUTHOR("Sugar <shuge@allwinnertech.com>"); 1094 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); 1095 MODULE_LICENSE("GPL"); 1096