1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * DMA driver for Nvidia's Tegra20 APB DMA controller. 4 * 5 * Copyright (c) 2012-2013, NVIDIA CORPORATION. All rights reserved. 6 */ 7 8 #include <linux/bitops.h> 9 #include <linux/clk.h> 10 #include <linux/delay.h> 11 #include <linux/dmaengine.h> 12 #include <linux/dma-mapping.h> 13 #include <linux/err.h> 14 #include <linux/init.h> 15 #include <linux/interrupt.h> 16 #include <linux/io.h> 17 #include <linux/mm.h> 18 #include <linux/module.h> 19 #include <linux/of.h> 20 #include <linux/of_device.h> 21 #include <linux/of_dma.h> 22 #include <linux/platform_device.h> 23 #include <linux/pm.h> 24 #include <linux/pm_runtime.h> 25 #include <linux/reset.h> 26 #include <linux/slab.h> 27 28 #include "dmaengine.h" 29 30 #define CREATE_TRACE_POINTS 31 #include <trace/events/tegra_apb_dma.h> 32 33 #define TEGRA_APBDMA_GENERAL 0x0 34 #define TEGRA_APBDMA_GENERAL_ENABLE BIT(31) 35 36 #define TEGRA_APBDMA_CONTROL 0x010 37 #define TEGRA_APBDMA_IRQ_MASK 0x01c 38 #define TEGRA_APBDMA_IRQ_MASK_SET 0x020 39 40 /* CSR register */ 41 #define TEGRA_APBDMA_CHAN_CSR 0x00 42 #define TEGRA_APBDMA_CSR_ENB BIT(31) 43 #define TEGRA_APBDMA_CSR_IE_EOC BIT(30) 44 #define TEGRA_APBDMA_CSR_HOLD BIT(29) 45 #define TEGRA_APBDMA_CSR_DIR BIT(28) 46 #define TEGRA_APBDMA_CSR_ONCE BIT(27) 47 #define TEGRA_APBDMA_CSR_FLOW BIT(21) 48 #define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT 16 49 #define TEGRA_APBDMA_CSR_REQ_SEL_MASK 0x1F 50 #define TEGRA_APBDMA_CSR_WCOUNT_MASK 0xFFFC 51 52 /* STATUS register */ 53 #define TEGRA_APBDMA_CHAN_STATUS 0x004 54 #define TEGRA_APBDMA_STATUS_BUSY BIT(31) 55 #define TEGRA_APBDMA_STATUS_ISE_EOC BIT(30) 56 #define TEGRA_APBDMA_STATUS_HALT BIT(29) 57 #define TEGRA_APBDMA_STATUS_PING_PONG BIT(28) 58 #define TEGRA_APBDMA_STATUS_COUNT_SHIFT 2 59 #define TEGRA_APBDMA_STATUS_COUNT_MASK 0xFFFC 60 61 #define TEGRA_APBDMA_CHAN_CSRE 0x00C 62 #define TEGRA_APBDMA_CHAN_CSRE_PAUSE (1 << 31) 63 64 /* AHB memory address */ 65 #define TEGRA_APBDMA_CHAN_AHBPTR 0x010 66 67 /* AHB sequence register */ 68 #define TEGRA_APBDMA_CHAN_AHBSEQ 0x14 69 #define TEGRA_APBDMA_AHBSEQ_INTR_ENB BIT(31) 70 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8 (0 << 28) 71 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16 (1 << 28) 72 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32 (2 << 28) 73 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64 (3 << 28) 74 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128 (4 << 28) 75 #define TEGRA_APBDMA_AHBSEQ_DATA_SWAP BIT(27) 76 #define TEGRA_APBDMA_AHBSEQ_BURST_1 (4 << 24) 77 #define TEGRA_APBDMA_AHBSEQ_BURST_4 (5 << 24) 78 #define TEGRA_APBDMA_AHBSEQ_BURST_8 (6 << 24) 79 #define TEGRA_APBDMA_AHBSEQ_DBL_BUF BIT(19) 80 #define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT 16 81 #define TEGRA_APBDMA_AHBSEQ_WRAP_NONE 0 82 83 /* APB address */ 84 #define TEGRA_APBDMA_CHAN_APBPTR 0x018 85 86 /* APB sequence register */ 87 #define TEGRA_APBDMA_CHAN_APBSEQ 0x01c 88 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8 (0 << 28) 89 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16 (1 << 28) 90 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32 (2 << 28) 91 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64 (3 << 28) 92 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128 (4 << 28) 93 #define TEGRA_APBDMA_APBSEQ_DATA_SWAP BIT(27) 94 #define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1 (1 << 16) 95 96 /* Tegra148 specific registers */ 97 #define TEGRA_APBDMA_CHAN_WCOUNT 0x20 98 99 #define TEGRA_APBDMA_CHAN_WORD_TRANSFER 0x24 100 101 /* 102 * If any burst is in flight and DMA paused then this is the time to complete 103 * on-flight burst and update DMA status register. 104 */ 105 #define TEGRA_APBDMA_BURST_COMPLETE_TIME 20 106 107 /* Channel base address offset from APBDMA base address */ 108 #define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET 0x1000 109 110 #define TEGRA_APBDMA_SLAVE_ID_INVALID (TEGRA_APBDMA_CSR_REQ_SEL_MASK + 1) 111 112 struct tegra_dma; 113 114 /* 115 * tegra_dma_chip_data Tegra chip specific DMA data 116 * @nr_channels: Number of channels available in the controller. 117 * @channel_reg_size: Channel register size/stride. 118 * @max_dma_count: Maximum DMA transfer count supported by DMA controller. 119 * @support_channel_pause: Support channel wise pause of dma. 120 * @support_separate_wcount_reg: Support separate word count register. 121 */ 122 struct tegra_dma_chip_data { 123 int nr_channels; 124 int channel_reg_size; 125 int max_dma_count; 126 bool support_channel_pause; 127 bool support_separate_wcount_reg; 128 }; 129 130 /* DMA channel registers */ 131 struct tegra_dma_channel_regs { 132 unsigned long csr; 133 unsigned long ahb_ptr; 134 unsigned long apb_ptr; 135 unsigned long ahb_seq; 136 unsigned long apb_seq; 137 unsigned long wcount; 138 }; 139 140 /* 141 * tegra_dma_sg_req: DMA request details to configure hardware. This 142 * contains the details for one transfer to configure DMA hw. 143 * The client's request for data transfer can be broken into multiple 144 * sub-transfer as per requester details and hw support. 145 * This sub transfer get added in the list of transfer and point to Tegra 146 * DMA descriptor which manages the transfer details. 147 */ 148 struct tegra_dma_sg_req { 149 struct tegra_dma_channel_regs ch_regs; 150 unsigned int req_len; 151 bool configured; 152 bool last_sg; 153 struct list_head node; 154 struct tegra_dma_desc *dma_desc; 155 }; 156 157 /* 158 * tegra_dma_desc: Tegra DMA descriptors which manages the client requests. 159 * This descriptor keep track of transfer status, callbacks and request 160 * counts etc. 161 */ 162 struct tegra_dma_desc { 163 struct dma_async_tx_descriptor txd; 164 unsigned int bytes_requested; 165 unsigned int bytes_transferred; 166 enum dma_status dma_status; 167 struct list_head node; 168 struct list_head tx_list; 169 struct list_head cb_node; 170 int cb_count; 171 }; 172 173 struct tegra_dma_channel; 174 175 typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc, 176 bool to_terminate); 177 178 /* tegra_dma_channel: Channel specific information */ 179 struct tegra_dma_channel { 180 struct dma_chan dma_chan; 181 char name[12]; 182 bool config_init; 183 int id; 184 int irq; 185 void __iomem *chan_addr; 186 spinlock_t lock; 187 bool busy; 188 struct tegra_dma *tdma; 189 bool cyclic; 190 191 /* Different lists for managing the requests */ 192 struct list_head free_sg_req; 193 struct list_head pending_sg_req; 194 struct list_head free_dma_desc; 195 struct list_head cb_desc; 196 197 /* ISR handler and tasklet for bottom half of isr handling */ 198 dma_isr_handler isr_handler; 199 struct tasklet_struct tasklet; 200 201 /* Channel-slave specific configuration */ 202 unsigned int slave_id; 203 struct dma_slave_config dma_sconfig; 204 struct tegra_dma_channel_regs channel_reg; 205 }; 206 207 /* tegra_dma: Tegra DMA specific information */ 208 struct tegra_dma { 209 struct dma_device dma_dev; 210 struct device *dev; 211 struct clk *dma_clk; 212 struct reset_control *rst; 213 spinlock_t global_lock; 214 void __iomem *base_addr; 215 const struct tegra_dma_chip_data *chip_data; 216 217 /* 218 * Counter for managing global pausing of the DMA controller. 219 * Only applicable for devices that don't support individual 220 * channel pausing. 221 */ 222 u32 global_pause_count; 223 224 /* Some register need to be cache before suspend */ 225 u32 reg_gen; 226 227 /* Last member of the structure */ 228 struct tegra_dma_channel channels[0]; 229 }; 230 231 static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val) 232 { 233 writel(val, tdma->base_addr + reg); 234 } 235 236 static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg) 237 { 238 return readl(tdma->base_addr + reg); 239 } 240 241 static inline void tdc_write(struct tegra_dma_channel *tdc, 242 u32 reg, u32 val) 243 { 244 writel(val, tdc->chan_addr + reg); 245 } 246 247 static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg) 248 { 249 return readl(tdc->chan_addr + reg); 250 } 251 252 static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc) 253 { 254 return container_of(dc, struct tegra_dma_channel, dma_chan); 255 } 256 257 static inline struct tegra_dma_desc *txd_to_tegra_dma_desc( 258 struct dma_async_tx_descriptor *td) 259 { 260 return container_of(td, struct tegra_dma_desc, txd); 261 } 262 263 static inline struct device *tdc2dev(struct tegra_dma_channel *tdc) 264 { 265 return &tdc->dma_chan.dev->device; 266 } 267 268 static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx); 269 static int tegra_dma_runtime_suspend(struct device *dev); 270 static int tegra_dma_runtime_resume(struct device *dev); 271 272 /* Get DMA desc from free list, if not there then allocate it. */ 273 static struct tegra_dma_desc *tegra_dma_desc_get( 274 struct tegra_dma_channel *tdc) 275 { 276 struct tegra_dma_desc *dma_desc; 277 unsigned long flags; 278 279 spin_lock_irqsave(&tdc->lock, flags); 280 281 /* Do not allocate if desc are waiting for ack */ 282 list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { 283 if (async_tx_test_ack(&dma_desc->txd)) { 284 list_del(&dma_desc->node); 285 spin_unlock_irqrestore(&tdc->lock, flags); 286 dma_desc->txd.flags = 0; 287 return dma_desc; 288 } 289 } 290 291 spin_unlock_irqrestore(&tdc->lock, flags); 292 293 /* Allocate DMA desc */ 294 dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT); 295 if (!dma_desc) 296 return NULL; 297 298 dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan); 299 dma_desc->txd.tx_submit = tegra_dma_tx_submit; 300 dma_desc->txd.flags = 0; 301 return dma_desc; 302 } 303 304 static void tegra_dma_desc_put(struct tegra_dma_channel *tdc, 305 struct tegra_dma_desc *dma_desc) 306 { 307 unsigned long flags; 308 309 spin_lock_irqsave(&tdc->lock, flags); 310 if (!list_empty(&dma_desc->tx_list)) 311 list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req); 312 list_add_tail(&dma_desc->node, &tdc->free_dma_desc); 313 spin_unlock_irqrestore(&tdc->lock, flags); 314 } 315 316 static struct tegra_dma_sg_req *tegra_dma_sg_req_get( 317 struct tegra_dma_channel *tdc) 318 { 319 struct tegra_dma_sg_req *sg_req = NULL; 320 unsigned long flags; 321 322 spin_lock_irqsave(&tdc->lock, flags); 323 if (!list_empty(&tdc->free_sg_req)) { 324 sg_req = list_first_entry(&tdc->free_sg_req, 325 typeof(*sg_req), node); 326 list_del(&sg_req->node); 327 spin_unlock_irqrestore(&tdc->lock, flags); 328 return sg_req; 329 } 330 spin_unlock_irqrestore(&tdc->lock, flags); 331 332 sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_NOWAIT); 333 334 return sg_req; 335 } 336 337 static int tegra_dma_slave_config(struct dma_chan *dc, 338 struct dma_slave_config *sconfig) 339 { 340 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 341 342 if (!list_empty(&tdc->pending_sg_req)) { 343 dev_err(tdc2dev(tdc), "Configuration not allowed\n"); 344 return -EBUSY; 345 } 346 347 memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig)); 348 if (tdc->slave_id == TEGRA_APBDMA_SLAVE_ID_INVALID && 349 sconfig->device_fc) { 350 if (sconfig->slave_id > TEGRA_APBDMA_CSR_REQ_SEL_MASK) 351 return -EINVAL; 352 tdc->slave_id = sconfig->slave_id; 353 } 354 tdc->config_init = true; 355 return 0; 356 } 357 358 static void tegra_dma_global_pause(struct tegra_dma_channel *tdc, 359 bool wait_for_burst_complete) 360 { 361 struct tegra_dma *tdma = tdc->tdma; 362 363 spin_lock(&tdma->global_lock); 364 365 if (tdc->tdma->global_pause_count == 0) { 366 tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0); 367 if (wait_for_burst_complete) 368 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); 369 } 370 371 tdc->tdma->global_pause_count++; 372 373 spin_unlock(&tdma->global_lock); 374 } 375 376 static void tegra_dma_global_resume(struct tegra_dma_channel *tdc) 377 { 378 struct tegra_dma *tdma = tdc->tdma; 379 380 spin_lock(&tdma->global_lock); 381 382 if (WARN_ON(tdc->tdma->global_pause_count == 0)) 383 goto out; 384 385 if (--tdc->tdma->global_pause_count == 0) 386 tdma_write(tdma, TEGRA_APBDMA_GENERAL, 387 TEGRA_APBDMA_GENERAL_ENABLE); 388 389 out: 390 spin_unlock(&tdma->global_lock); 391 } 392 393 static void tegra_dma_pause(struct tegra_dma_channel *tdc, 394 bool wait_for_burst_complete) 395 { 396 struct tegra_dma *tdma = tdc->tdma; 397 398 if (tdma->chip_data->support_channel_pause) { 399 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 400 TEGRA_APBDMA_CHAN_CSRE_PAUSE); 401 if (wait_for_burst_complete) 402 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); 403 } else { 404 tegra_dma_global_pause(tdc, wait_for_burst_complete); 405 } 406 } 407 408 static void tegra_dma_resume(struct tegra_dma_channel *tdc) 409 { 410 struct tegra_dma *tdma = tdc->tdma; 411 412 if (tdma->chip_data->support_channel_pause) { 413 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0); 414 } else { 415 tegra_dma_global_resume(tdc); 416 } 417 } 418 419 static void tegra_dma_stop(struct tegra_dma_channel *tdc) 420 { 421 u32 csr; 422 u32 status; 423 424 /* Disable interrupts */ 425 csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR); 426 csr &= ~TEGRA_APBDMA_CSR_IE_EOC; 427 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); 428 429 /* Disable DMA */ 430 csr &= ~TEGRA_APBDMA_CSR_ENB; 431 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); 432 433 /* Clear interrupt status if it is there */ 434 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); 435 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { 436 dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__); 437 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); 438 } 439 tdc->busy = false; 440 } 441 442 static void tegra_dma_start(struct tegra_dma_channel *tdc, 443 struct tegra_dma_sg_req *sg_req) 444 { 445 struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs; 446 447 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr); 448 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq); 449 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr); 450 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq); 451 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr); 452 if (tdc->tdma->chip_data->support_separate_wcount_reg) 453 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_regs->wcount); 454 455 /* Start DMA */ 456 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, 457 ch_regs->csr | TEGRA_APBDMA_CSR_ENB); 458 } 459 460 static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc, 461 struct tegra_dma_sg_req *nsg_req) 462 { 463 unsigned long status; 464 465 /* 466 * The DMA controller reloads the new configuration for next transfer 467 * after last burst of current transfer completes. 468 * If there is no IEC status then this makes sure that last burst 469 * has not be completed. There may be case that last burst is on 470 * flight and so it can complete but because DMA is paused, it 471 * will not generates interrupt as well as not reload the new 472 * configuration. 473 * If there is already IEC status then interrupt handler need to 474 * load new configuration. 475 */ 476 tegra_dma_pause(tdc, false); 477 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); 478 479 /* 480 * If interrupt is pending then do nothing as the ISR will handle 481 * the programing for new request. 482 */ 483 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { 484 dev_err(tdc2dev(tdc), 485 "Skipping new configuration as interrupt is pending\n"); 486 tegra_dma_resume(tdc); 487 return; 488 } 489 490 /* Safe to program new configuration */ 491 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr); 492 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr); 493 if (tdc->tdma->chip_data->support_separate_wcount_reg) 494 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, 495 nsg_req->ch_regs.wcount); 496 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, 497 nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB); 498 nsg_req->configured = true; 499 500 tegra_dma_resume(tdc); 501 } 502 503 static void tdc_start_head_req(struct tegra_dma_channel *tdc) 504 { 505 struct tegra_dma_sg_req *sg_req; 506 507 if (list_empty(&tdc->pending_sg_req)) 508 return; 509 510 sg_req = list_first_entry(&tdc->pending_sg_req, 511 typeof(*sg_req), node); 512 tegra_dma_start(tdc, sg_req); 513 sg_req->configured = true; 514 tdc->busy = true; 515 } 516 517 static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc) 518 { 519 struct tegra_dma_sg_req *hsgreq; 520 struct tegra_dma_sg_req *hnsgreq; 521 522 if (list_empty(&tdc->pending_sg_req)) 523 return; 524 525 hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); 526 if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) { 527 hnsgreq = list_first_entry(&hsgreq->node, 528 typeof(*hnsgreq), node); 529 tegra_dma_configure_for_next(tdc, hnsgreq); 530 } 531 } 532 533 static inline int get_current_xferred_count(struct tegra_dma_channel *tdc, 534 struct tegra_dma_sg_req *sg_req, unsigned long status) 535 { 536 return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4; 537 } 538 539 static void tegra_dma_abort_all(struct tegra_dma_channel *tdc) 540 { 541 struct tegra_dma_sg_req *sgreq; 542 struct tegra_dma_desc *dma_desc; 543 544 while (!list_empty(&tdc->pending_sg_req)) { 545 sgreq = list_first_entry(&tdc->pending_sg_req, 546 typeof(*sgreq), node); 547 list_move_tail(&sgreq->node, &tdc->free_sg_req); 548 if (sgreq->last_sg) { 549 dma_desc = sgreq->dma_desc; 550 dma_desc->dma_status = DMA_ERROR; 551 list_add_tail(&dma_desc->node, &tdc->free_dma_desc); 552 553 /* Add in cb list if it is not there. */ 554 if (!dma_desc->cb_count) 555 list_add_tail(&dma_desc->cb_node, 556 &tdc->cb_desc); 557 dma_desc->cb_count++; 558 } 559 } 560 tdc->isr_handler = NULL; 561 } 562 563 static bool handle_continuous_head_request(struct tegra_dma_channel *tdc, 564 struct tegra_dma_sg_req *last_sg_req, bool to_terminate) 565 { 566 struct tegra_dma_sg_req *hsgreq = NULL; 567 568 if (list_empty(&tdc->pending_sg_req)) { 569 dev_err(tdc2dev(tdc), "DMA is running without req\n"); 570 tegra_dma_stop(tdc); 571 return false; 572 } 573 574 /* 575 * Check that head req on list should be in flight. 576 * If it is not in flight then abort transfer as 577 * looping of transfer can not continue. 578 */ 579 hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); 580 if (!hsgreq->configured) { 581 tegra_dma_stop(tdc); 582 dev_err(tdc2dev(tdc), "Error in DMA transfer, aborting DMA\n"); 583 tegra_dma_abort_all(tdc); 584 return false; 585 } 586 587 /* Configure next request */ 588 if (!to_terminate) 589 tdc_configure_next_head_desc(tdc); 590 return true; 591 } 592 593 static void handle_once_dma_done(struct tegra_dma_channel *tdc, 594 bool to_terminate) 595 { 596 struct tegra_dma_sg_req *sgreq; 597 struct tegra_dma_desc *dma_desc; 598 599 tdc->busy = false; 600 sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); 601 dma_desc = sgreq->dma_desc; 602 dma_desc->bytes_transferred += sgreq->req_len; 603 604 list_del(&sgreq->node); 605 if (sgreq->last_sg) { 606 dma_desc->dma_status = DMA_COMPLETE; 607 dma_cookie_complete(&dma_desc->txd); 608 if (!dma_desc->cb_count) 609 list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); 610 dma_desc->cb_count++; 611 list_add_tail(&dma_desc->node, &tdc->free_dma_desc); 612 } 613 list_add_tail(&sgreq->node, &tdc->free_sg_req); 614 615 /* Do not start DMA if it is going to be terminate */ 616 if (to_terminate || list_empty(&tdc->pending_sg_req)) 617 return; 618 619 tdc_start_head_req(tdc); 620 } 621 622 static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc, 623 bool to_terminate) 624 { 625 struct tegra_dma_sg_req *sgreq; 626 struct tegra_dma_desc *dma_desc; 627 bool st; 628 629 sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); 630 dma_desc = sgreq->dma_desc; 631 /* if we dma for long enough the transfer count will wrap */ 632 dma_desc->bytes_transferred = 633 (dma_desc->bytes_transferred + sgreq->req_len) % 634 dma_desc->bytes_requested; 635 636 /* Callback need to be call */ 637 if (!dma_desc->cb_count) 638 list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); 639 dma_desc->cb_count++; 640 641 /* If not last req then put at end of pending list */ 642 if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) { 643 list_move_tail(&sgreq->node, &tdc->pending_sg_req); 644 sgreq->configured = false; 645 st = handle_continuous_head_request(tdc, sgreq, to_terminate); 646 if (!st) 647 dma_desc->dma_status = DMA_ERROR; 648 } 649 } 650 651 static void tegra_dma_tasklet(unsigned long data) 652 { 653 struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data; 654 struct dmaengine_desc_callback cb; 655 struct tegra_dma_desc *dma_desc; 656 unsigned long flags; 657 int cb_count; 658 659 spin_lock_irqsave(&tdc->lock, flags); 660 while (!list_empty(&tdc->cb_desc)) { 661 dma_desc = list_first_entry(&tdc->cb_desc, 662 typeof(*dma_desc), cb_node); 663 list_del(&dma_desc->cb_node); 664 dmaengine_desc_get_callback(&dma_desc->txd, &cb); 665 cb_count = dma_desc->cb_count; 666 dma_desc->cb_count = 0; 667 trace_tegra_dma_complete_cb(&tdc->dma_chan, cb_count, 668 cb.callback); 669 spin_unlock_irqrestore(&tdc->lock, flags); 670 while (cb_count--) 671 dmaengine_desc_callback_invoke(&cb, NULL); 672 spin_lock_irqsave(&tdc->lock, flags); 673 } 674 spin_unlock_irqrestore(&tdc->lock, flags); 675 } 676 677 static irqreturn_t tegra_dma_isr(int irq, void *dev_id) 678 { 679 struct tegra_dma_channel *tdc = dev_id; 680 unsigned long status; 681 unsigned long flags; 682 683 spin_lock_irqsave(&tdc->lock, flags); 684 685 trace_tegra_dma_isr(&tdc->dma_chan, irq); 686 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); 687 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { 688 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); 689 tdc->isr_handler(tdc, false); 690 tasklet_schedule(&tdc->tasklet); 691 spin_unlock_irqrestore(&tdc->lock, flags); 692 return IRQ_HANDLED; 693 } 694 695 spin_unlock_irqrestore(&tdc->lock, flags); 696 dev_info(tdc2dev(tdc), 697 "Interrupt already served status 0x%08lx\n", status); 698 return IRQ_NONE; 699 } 700 701 static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd) 702 { 703 struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd); 704 struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan); 705 unsigned long flags; 706 dma_cookie_t cookie; 707 708 spin_lock_irqsave(&tdc->lock, flags); 709 dma_desc->dma_status = DMA_IN_PROGRESS; 710 cookie = dma_cookie_assign(&dma_desc->txd); 711 list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req); 712 spin_unlock_irqrestore(&tdc->lock, flags); 713 return cookie; 714 } 715 716 static void tegra_dma_issue_pending(struct dma_chan *dc) 717 { 718 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 719 unsigned long flags; 720 721 spin_lock_irqsave(&tdc->lock, flags); 722 if (list_empty(&tdc->pending_sg_req)) { 723 dev_err(tdc2dev(tdc), "No DMA request\n"); 724 goto end; 725 } 726 if (!tdc->busy) { 727 tdc_start_head_req(tdc); 728 729 /* Continuous single mode: Configure next req */ 730 if (tdc->cyclic) { 731 /* 732 * Wait for 1 burst time for configure DMA for 733 * next transfer. 734 */ 735 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); 736 tdc_configure_next_head_desc(tdc); 737 } 738 } 739 end: 740 spin_unlock_irqrestore(&tdc->lock, flags); 741 } 742 743 static int tegra_dma_terminate_all(struct dma_chan *dc) 744 { 745 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 746 struct tegra_dma_sg_req *sgreq; 747 struct tegra_dma_desc *dma_desc; 748 unsigned long flags; 749 unsigned long status; 750 unsigned long wcount; 751 bool was_busy; 752 753 spin_lock_irqsave(&tdc->lock, flags); 754 if (list_empty(&tdc->pending_sg_req)) { 755 spin_unlock_irqrestore(&tdc->lock, flags); 756 return 0; 757 } 758 759 if (!tdc->busy) 760 goto skip_dma_stop; 761 762 /* Pause DMA before checking the queue status */ 763 tegra_dma_pause(tdc, true); 764 765 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); 766 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { 767 dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__); 768 tdc->isr_handler(tdc, true); 769 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); 770 } 771 if (tdc->tdma->chip_data->support_separate_wcount_reg) 772 wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER); 773 else 774 wcount = status; 775 776 was_busy = tdc->busy; 777 tegra_dma_stop(tdc); 778 779 if (!list_empty(&tdc->pending_sg_req) && was_busy) { 780 sgreq = list_first_entry(&tdc->pending_sg_req, 781 typeof(*sgreq), node); 782 sgreq->dma_desc->bytes_transferred += 783 get_current_xferred_count(tdc, sgreq, wcount); 784 } 785 tegra_dma_resume(tdc); 786 787 skip_dma_stop: 788 tegra_dma_abort_all(tdc); 789 790 while (!list_empty(&tdc->cb_desc)) { 791 dma_desc = list_first_entry(&tdc->cb_desc, 792 typeof(*dma_desc), cb_node); 793 list_del(&dma_desc->cb_node); 794 dma_desc->cb_count = 0; 795 } 796 spin_unlock_irqrestore(&tdc->lock, flags); 797 return 0; 798 } 799 800 static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, 801 dma_cookie_t cookie, struct dma_tx_state *txstate) 802 { 803 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 804 struct tegra_dma_desc *dma_desc; 805 struct tegra_dma_sg_req *sg_req; 806 enum dma_status ret; 807 unsigned long flags; 808 unsigned int residual; 809 810 ret = dma_cookie_status(dc, cookie, txstate); 811 if (ret == DMA_COMPLETE) 812 return ret; 813 814 spin_lock_irqsave(&tdc->lock, flags); 815 816 /* Check on wait_ack desc status */ 817 list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { 818 if (dma_desc->txd.cookie == cookie) { 819 ret = dma_desc->dma_status; 820 goto found; 821 } 822 } 823 824 /* Check in pending list */ 825 list_for_each_entry(sg_req, &tdc->pending_sg_req, node) { 826 dma_desc = sg_req->dma_desc; 827 if (dma_desc->txd.cookie == cookie) { 828 ret = dma_desc->dma_status; 829 goto found; 830 } 831 } 832 833 dev_dbg(tdc2dev(tdc), "cookie %d not found\n", cookie); 834 dma_desc = NULL; 835 836 found: 837 if (dma_desc && txstate) { 838 residual = dma_desc->bytes_requested - 839 (dma_desc->bytes_transferred % 840 dma_desc->bytes_requested); 841 dma_set_residue(txstate, residual); 842 } 843 844 trace_tegra_dma_tx_status(&tdc->dma_chan, cookie, txstate); 845 spin_unlock_irqrestore(&tdc->lock, flags); 846 return ret; 847 } 848 849 static inline int get_bus_width(struct tegra_dma_channel *tdc, 850 enum dma_slave_buswidth slave_bw) 851 { 852 switch (slave_bw) { 853 case DMA_SLAVE_BUSWIDTH_1_BYTE: 854 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8; 855 case DMA_SLAVE_BUSWIDTH_2_BYTES: 856 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16; 857 case DMA_SLAVE_BUSWIDTH_4_BYTES: 858 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; 859 case DMA_SLAVE_BUSWIDTH_8_BYTES: 860 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64; 861 default: 862 dev_warn(tdc2dev(tdc), 863 "slave bw is not supported, using 32bits\n"); 864 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; 865 } 866 } 867 868 static inline int get_burst_size(struct tegra_dma_channel *tdc, 869 u32 burst_size, enum dma_slave_buswidth slave_bw, int len) 870 { 871 int burst_byte; 872 int burst_ahb_width; 873 874 /* 875 * burst_size from client is in terms of the bus_width. 876 * convert them into AHB memory width which is 4 byte. 877 */ 878 burst_byte = burst_size * slave_bw; 879 burst_ahb_width = burst_byte / 4; 880 881 /* If burst size is 0 then calculate the burst size based on length */ 882 if (!burst_ahb_width) { 883 if (len & 0xF) 884 return TEGRA_APBDMA_AHBSEQ_BURST_1; 885 else if ((len >> 4) & 0x1) 886 return TEGRA_APBDMA_AHBSEQ_BURST_4; 887 else 888 return TEGRA_APBDMA_AHBSEQ_BURST_8; 889 } 890 if (burst_ahb_width < 4) 891 return TEGRA_APBDMA_AHBSEQ_BURST_1; 892 else if (burst_ahb_width < 8) 893 return TEGRA_APBDMA_AHBSEQ_BURST_4; 894 else 895 return TEGRA_APBDMA_AHBSEQ_BURST_8; 896 } 897 898 static int get_transfer_param(struct tegra_dma_channel *tdc, 899 enum dma_transfer_direction direction, unsigned long *apb_addr, 900 unsigned long *apb_seq, unsigned long *csr, unsigned int *burst_size, 901 enum dma_slave_buswidth *slave_bw) 902 { 903 switch (direction) { 904 case DMA_MEM_TO_DEV: 905 *apb_addr = tdc->dma_sconfig.dst_addr; 906 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width); 907 *burst_size = tdc->dma_sconfig.dst_maxburst; 908 *slave_bw = tdc->dma_sconfig.dst_addr_width; 909 *csr = TEGRA_APBDMA_CSR_DIR; 910 return 0; 911 912 case DMA_DEV_TO_MEM: 913 *apb_addr = tdc->dma_sconfig.src_addr; 914 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width); 915 *burst_size = tdc->dma_sconfig.src_maxburst; 916 *slave_bw = tdc->dma_sconfig.src_addr_width; 917 *csr = 0; 918 return 0; 919 920 default: 921 dev_err(tdc2dev(tdc), "DMA direction is not supported\n"); 922 return -EINVAL; 923 } 924 return -EINVAL; 925 } 926 927 static void tegra_dma_prep_wcount(struct tegra_dma_channel *tdc, 928 struct tegra_dma_channel_regs *ch_regs, u32 len) 929 { 930 u32 len_field = (len - 4) & 0xFFFC; 931 932 if (tdc->tdma->chip_data->support_separate_wcount_reg) 933 ch_regs->wcount = len_field; 934 else 935 ch_regs->csr |= len_field; 936 } 937 938 static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg( 939 struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len, 940 enum dma_transfer_direction direction, unsigned long flags, 941 void *context) 942 { 943 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 944 struct tegra_dma_desc *dma_desc; 945 unsigned int i; 946 struct scatterlist *sg; 947 unsigned long csr, ahb_seq, apb_ptr, apb_seq; 948 struct list_head req_list; 949 struct tegra_dma_sg_req *sg_req = NULL; 950 u32 burst_size; 951 enum dma_slave_buswidth slave_bw; 952 953 if (!tdc->config_init) { 954 dev_err(tdc2dev(tdc), "DMA channel is not configured\n"); 955 return NULL; 956 } 957 if (sg_len < 1) { 958 dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len); 959 return NULL; 960 } 961 962 if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, 963 &burst_size, &slave_bw) < 0) 964 return NULL; 965 966 INIT_LIST_HEAD(&req_list); 967 968 ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; 969 ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << 970 TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; 971 ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; 972 973 csr |= TEGRA_APBDMA_CSR_ONCE; 974 975 if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) { 976 csr |= TEGRA_APBDMA_CSR_FLOW; 977 csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; 978 } 979 980 if (flags & DMA_PREP_INTERRUPT) 981 csr |= TEGRA_APBDMA_CSR_IE_EOC; 982 983 apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; 984 985 dma_desc = tegra_dma_desc_get(tdc); 986 if (!dma_desc) { 987 dev_err(tdc2dev(tdc), "DMA descriptors not available\n"); 988 return NULL; 989 } 990 INIT_LIST_HEAD(&dma_desc->tx_list); 991 INIT_LIST_HEAD(&dma_desc->cb_node); 992 dma_desc->cb_count = 0; 993 dma_desc->bytes_requested = 0; 994 dma_desc->bytes_transferred = 0; 995 dma_desc->dma_status = DMA_IN_PROGRESS; 996 997 /* Make transfer requests */ 998 for_each_sg(sgl, sg, sg_len, i) { 999 u32 len, mem; 1000 1001 mem = sg_dma_address(sg); 1002 len = sg_dma_len(sg); 1003 1004 if ((len & 3) || (mem & 3) || 1005 (len > tdc->tdma->chip_data->max_dma_count)) { 1006 dev_err(tdc2dev(tdc), 1007 "DMA length/memory address is not supported\n"); 1008 tegra_dma_desc_put(tdc, dma_desc); 1009 return NULL; 1010 } 1011 1012 sg_req = tegra_dma_sg_req_get(tdc); 1013 if (!sg_req) { 1014 dev_err(tdc2dev(tdc), "DMA sg-req not available\n"); 1015 tegra_dma_desc_put(tdc, dma_desc); 1016 return NULL; 1017 } 1018 1019 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); 1020 dma_desc->bytes_requested += len; 1021 1022 sg_req->ch_regs.apb_ptr = apb_ptr; 1023 sg_req->ch_regs.ahb_ptr = mem; 1024 sg_req->ch_regs.csr = csr; 1025 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len); 1026 sg_req->ch_regs.apb_seq = apb_seq; 1027 sg_req->ch_regs.ahb_seq = ahb_seq; 1028 sg_req->configured = false; 1029 sg_req->last_sg = false; 1030 sg_req->dma_desc = dma_desc; 1031 sg_req->req_len = len; 1032 1033 list_add_tail(&sg_req->node, &dma_desc->tx_list); 1034 } 1035 sg_req->last_sg = true; 1036 if (flags & DMA_CTRL_ACK) 1037 dma_desc->txd.flags = DMA_CTRL_ACK; 1038 1039 /* 1040 * Make sure that mode should not be conflicting with currently 1041 * configured mode. 1042 */ 1043 if (!tdc->isr_handler) { 1044 tdc->isr_handler = handle_once_dma_done; 1045 tdc->cyclic = false; 1046 } else { 1047 if (tdc->cyclic) { 1048 dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n"); 1049 tegra_dma_desc_put(tdc, dma_desc); 1050 return NULL; 1051 } 1052 } 1053 1054 return &dma_desc->txd; 1055 } 1056 1057 static struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic( 1058 struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len, 1059 size_t period_len, enum dma_transfer_direction direction, 1060 unsigned long flags) 1061 { 1062 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 1063 struct tegra_dma_desc *dma_desc = NULL; 1064 struct tegra_dma_sg_req *sg_req = NULL; 1065 unsigned long csr, ahb_seq, apb_ptr, apb_seq; 1066 int len; 1067 size_t remain_len; 1068 dma_addr_t mem = buf_addr; 1069 u32 burst_size; 1070 enum dma_slave_buswidth slave_bw; 1071 1072 if (!buf_len || !period_len) { 1073 dev_err(tdc2dev(tdc), "Invalid buffer/period len\n"); 1074 return NULL; 1075 } 1076 1077 if (!tdc->config_init) { 1078 dev_err(tdc2dev(tdc), "DMA slave is not configured\n"); 1079 return NULL; 1080 } 1081 1082 /* 1083 * We allow to take more number of requests till DMA is 1084 * not started. The driver will loop over all requests. 1085 * Once DMA is started then new requests can be queued only after 1086 * terminating the DMA. 1087 */ 1088 if (tdc->busy) { 1089 dev_err(tdc2dev(tdc), "Request not allowed when DMA running\n"); 1090 return NULL; 1091 } 1092 1093 /* 1094 * We only support cycle transfer when buf_len is multiple of 1095 * period_len. 1096 */ 1097 if (buf_len % period_len) { 1098 dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n"); 1099 return NULL; 1100 } 1101 1102 len = period_len; 1103 if ((len & 3) || (buf_addr & 3) || 1104 (len > tdc->tdma->chip_data->max_dma_count)) { 1105 dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n"); 1106 return NULL; 1107 } 1108 1109 if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, 1110 &burst_size, &slave_bw) < 0) 1111 return NULL; 1112 1113 ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; 1114 ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << 1115 TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; 1116 ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; 1117 1118 if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) { 1119 csr |= TEGRA_APBDMA_CSR_FLOW; 1120 csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; 1121 } 1122 1123 if (flags & DMA_PREP_INTERRUPT) 1124 csr |= TEGRA_APBDMA_CSR_IE_EOC; 1125 1126 apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; 1127 1128 dma_desc = tegra_dma_desc_get(tdc); 1129 if (!dma_desc) { 1130 dev_err(tdc2dev(tdc), "not enough descriptors available\n"); 1131 return NULL; 1132 } 1133 1134 INIT_LIST_HEAD(&dma_desc->tx_list); 1135 INIT_LIST_HEAD(&dma_desc->cb_node); 1136 dma_desc->cb_count = 0; 1137 1138 dma_desc->bytes_transferred = 0; 1139 dma_desc->bytes_requested = buf_len; 1140 remain_len = buf_len; 1141 1142 /* Split transfer equal to period size */ 1143 while (remain_len) { 1144 sg_req = tegra_dma_sg_req_get(tdc); 1145 if (!sg_req) { 1146 dev_err(tdc2dev(tdc), "DMA sg-req not available\n"); 1147 tegra_dma_desc_put(tdc, dma_desc); 1148 return NULL; 1149 } 1150 1151 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); 1152 sg_req->ch_regs.apb_ptr = apb_ptr; 1153 sg_req->ch_regs.ahb_ptr = mem; 1154 sg_req->ch_regs.csr = csr; 1155 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len); 1156 sg_req->ch_regs.apb_seq = apb_seq; 1157 sg_req->ch_regs.ahb_seq = ahb_seq; 1158 sg_req->configured = false; 1159 sg_req->last_sg = false; 1160 sg_req->dma_desc = dma_desc; 1161 sg_req->req_len = len; 1162 1163 list_add_tail(&sg_req->node, &dma_desc->tx_list); 1164 remain_len -= len; 1165 mem += len; 1166 } 1167 sg_req->last_sg = true; 1168 if (flags & DMA_CTRL_ACK) 1169 dma_desc->txd.flags = DMA_CTRL_ACK; 1170 1171 /* 1172 * Make sure that mode should not be conflicting with currently 1173 * configured mode. 1174 */ 1175 if (!tdc->isr_handler) { 1176 tdc->isr_handler = handle_cont_sngl_cycle_dma_done; 1177 tdc->cyclic = true; 1178 } else { 1179 if (!tdc->cyclic) { 1180 dev_err(tdc2dev(tdc), "DMA configuration conflict\n"); 1181 tegra_dma_desc_put(tdc, dma_desc); 1182 return NULL; 1183 } 1184 } 1185 1186 return &dma_desc->txd; 1187 } 1188 1189 static int tegra_dma_alloc_chan_resources(struct dma_chan *dc) 1190 { 1191 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 1192 struct tegra_dma *tdma = tdc->tdma; 1193 int ret; 1194 1195 dma_cookie_init(&tdc->dma_chan); 1196 tdc->config_init = false; 1197 1198 ret = pm_runtime_get_sync(tdma->dev); 1199 if (ret < 0) 1200 return ret; 1201 1202 return 0; 1203 } 1204 1205 static void tegra_dma_free_chan_resources(struct dma_chan *dc) 1206 { 1207 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); 1208 struct tegra_dma *tdma = tdc->tdma; 1209 struct tegra_dma_desc *dma_desc; 1210 struct tegra_dma_sg_req *sg_req; 1211 struct list_head dma_desc_list; 1212 struct list_head sg_req_list; 1213 unsigned long flags; 1214 1215 INIT_LIST_HEAD(&dma_desc_list); 1216 INIT_LIST_HEAD(&sg_req_list); 1217 1218 dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); 1219 1220 if (tdc->busy) 1221 tegra_dma_terminate_all(dc); 1222 1223 spin_lock_irqsave(&tdc->lock, flags); 1224 list_splice_init(&tdc->pending_sg_req, &sg_req_list); 1225 list_splice_init(&tdc->free_sg_req, &sg_req_list); 1226 list_splice_init(&tdc->free_dma_desc, &dma_desc_list); 1227 INIT_LIST_HEAD(&tdc->cb_desc); 1228 tdc->config_init = false; 1229 tdc->isr_handler = NULL; 1230 spin_unlock_irqrestore(&tdc->lock, flags); 1231 1232 while (!list_empty(&dma_desc_list)) { 1233 dma_desc = list_first_entry(&dma_desc_list, 1234 typeof(*dma_desc), node); 1235 list_del(&dma_desc->node); 1236 kfree(dma_desc); 1237 } 1238 1239 while (!list_empty(&sg_req_list)) { 1240 sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node); 1241 list_del(&sg_req->node); 1242 kfree(sg_req); 1243 } 1244 pm_runtime_put(tdma->dev); 1245 1246 tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID; 1247 } 1248 1249 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec, 1250 struct of_dma *ofdma) 1251 { 1252 struct tegra_dma *tdma = ofdma->of_dma_data; 1253 struct dma_chan *chan; 1254 struct tegra_dma_channel *tdc; 1255 1256 if (dma_spec->args[0] > TEGRA_APBDMA_CSR_REQ_SEL_MASK) { 1257 dev_err(tdma->dev, "Invalid slave id: %d\n", dma_spec->args[0]); 1258 return NULL; 1259 } 1260 1261 chan = dma_get_any_slave_channel(&tdma->dma_dev); 1262 if (!chan) 1263 return NULL; 1264 1265 tdc = to_tegra_dma_chan(chan); 1266 tdc->slave_id = dma_spec->args[0]; 1267 1268 return chan; 1269 } 1270 1271 /* Tegra20 specific DMA controller information */ 1272 static const struct tegra_dma_chip_data tegra20_dma_chip_data = { 1273 .nr_channels = 16, 1274 .channel_reg_size = 0x20, 1275 .max_dma_count = 1024UL * 64, 1276 .support_channel_pause = false, 1277 .support_separate_wcount_reg = false, 1278 }; 1279 1280 /* Tegra30 specific DMA controller information */ 1281 static const struct tegra_dma_chip_data tegra30_dma_chip_data = { 1282 .nr_channels = 32, 1283 .channel_reg_size = 0x20, 1284 .max_dma_count = 1024UL * 64, 1285 .support_channel_pause = false, 1286 .support_separate_wcount_reg = false, 1287 }; 1288 1289 /* Tegra114 specific DMA controller information */ 1290 static const struct tegra_dma_chip_data tegra114_dma_chip_data = { 1291 .nr_channels = 32, 1292 .channel_reg_size = 0x20, 1293 .max_dma_count = 1024UL * 64, 1294 .support_channel_pause = true, 1295 .support_separate_wcount_reg = false, 1296 }; 1297 1298 /* Tegra148 specific DMA controller information */ 1299 static const struct tegra_dma_chip_data tegra148_dma_chip_data = { 1300 .nr_channels = 32, 1301 .channel_reg_size = 0x40, 1302 .max_dma_count = 1024UL * 64, 1303 .support_channel_pause = true, 1304 .support_separate_wcount_reg = true, 1305 }; 1306 1307 static int tegra_dma_probe(struct platform_device *pdev) 1308 { 1309 struct resource *res; 1310 struct tegra_dma *tdma; 1311 int ret; 1312 int i; 1313 const struct tegra_dma_chip_data *cdata; 1314 1315 cdata = of_device_get_match_data(&pdev->dev); 1316 if (!cdata) { 1317 dev_err(&pdev->dev, "Error: No device match data found\n"); 1318 return -ENODEV; 1319 } 1320 1321 tdma = devm_kzalloc(&pdev->dev, 1322 struct_size(tdma, channels, cdata->nr_channels), 1323 GFP_KERNEL); 1324 if (!tdma) 1325 return -ENOMEM; 1326 1327 tdma->dev = &pdev->dev; 1328 tdma->chip_data = cdata; 1329 platform_set_drvdata(pdev, tdma); 1330 1331 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1332 tdma->base_addr = devm_ioremap_resource(&pdev->dev, res); 1333 if (IS_ERR(tdma->base_addr)) 1334 return PTR_ERR(tdma->base_addr); 1335 1336 tdma->dma_clk = devm_clk_get(&pdev->dev, NULL); 1337 if (IS_ERR(tdma->dma_clk)) { 1338 dev_err(&pdev->dev, "Error: Missing controller clock\n"); 1339 return PTR_ERR(tdma->dma_clk); 1340 } 1341 1342 tdma->rst = devm_reset_control_get(&pdev->dev, "dma"); 1343 if (IS_ERR(tdma->rst)) { 1344 dev_err(&pdev->dev, "Error: Missing reset\n"); 1345 return PTR_ERR(tdma->rst); 1346 } 1347 1348 spin_lock_init(&tdma->global_lock); 1349 1350 pm_runtime_enable(&pdev->dev); 1351 if (!pm_runtime_enabled(&pdev->dev)) 1352 ret = tegra_dma_runtime_resume(&pdev->dev); 1353 else 1354 ret = pm_runtime_get_sync(&pdev->dev); 1355 1356 if (ret < 0) { 1357 pm_runtime_disable(&pdev->dev); 1358 return ret; 1359 } 1360 1361 /* Reset DMA controller */ 1362 reset_control_assert(tdma->rst); 1363 udelay(2); 1364 reset_control_deassert(tdma->rst); 1365 1366 /* Enable global DMA registers */ 1367 tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE); 1368 tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); 1369 tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul); 1370 1371 pm_runtime_put(&pdev->dev); 1372 1373 INIT_LIST_HEAD(&tdma->dma_dev.channels); 1374 for (i = 0; i < cdata->nr_channels; i++) { 1375 struct tegra_dma_channel *tdc = &tdma->channels[i]; 1376 1377 tdc->chan_addr = tdma->base_addr + 1378 TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET + 1379 (i * cdata->channel_reg_size); 1380 1381 res = platform_get_resource(pdev, IORESOURCE_IRQ, i); 1382 if (!res) { 1383 ret = -EINVAL; 1384 dev_err(&pdev->dev, "No irq resource for chan %d\n", i); 1385 goto err_irq; 1386 } 1387 tdc->irq = res->start; 1388 snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i); 1389 ret = request_irq(tdc->irq, tegra_dma_isr, 0, tdc->name, tdc); 1390 if (ret) { 1391 dev_err(&pdev->dev, 1392 "request_irq failed with err %d channel %d\n", 1393 ret, i); 1394 goto err_irq; 1395 } 1396 1397 tdc->dma_chan.device = &tdma->dma_dev; 1398 dma_cookie_init(&tdc->dma_chan); 1399 list_add_tail(&tdc->dma_chan.device_node, 1400 &tdma->dma_dev.channels); 1401 tdc->tdma = tdma; 1402 tdc->id = i; 1403 tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID; 1404 1405 tasklet_init(&tdc->tasklet, tegra_dma_tasklet, 1406 (unsigned long)tdc); 1407 spin_lock_init(&tdc->lock); 1408 1409 INIT_LIST_HEAD(&tdc->pending_sg_req); 1410 INIT_LIST_HEAD(&tdc->free_sg_req); 1411 INIT_LIST_HEAD(&tdc->free_dma_desc); 1412 INIT_LIST_HEAD(&tdc->cb_desc); 1413 } 1414 1415 dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask); 1416 dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask); 1417 dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask); 1418 1419 tdma->global_pause_count = 0; 1420 tdma->dma_dev.dev = &pdev->dev; 1421 tdma->dma_dev.device_alloc_chan_resources = 1422 tegra_dma_alloc_chan_resources; 1423 tdma->dma_dev.device_free_chan_resources = 1424 tegra_dma_free_chan_resources; 1425 tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg; 1426 tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic; 1427 tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | 1428 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | 1429 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | 1430 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES); 1431 tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | 1432 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | 1433 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | 1434 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES); 1435 tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); 1436 /* 1437 * XXX The hardware appears to support 1438 * DMA_RESIDUE_GRANULARITY_BURST-level reporting, but it's 1439 * only used by this driver during tegra_dma_terminate_all() 1440 */ 1441 tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; 1442 tdma->dma_dev.device_config = tegra_dma_slave_config; 1443 tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all; 1444 tdma->dma_dev.device_tx_status = tegra_dma_tx_status; 1445 tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending; 1446 1447 ret = dma_async_device_register(&tdma->dma_dev); 1448 if (ret < 0) { 1449 dev_err(&pdev->dev, 1450 "Tegra20 APB DMA driver registration failed %d\n", ret); 1451 goto err_irq; 1452 } 1453 1454 ret = of_dma_controller_register(pdev->dev.of_node, 1455 tegra_dma_of_xlate, tdma); 1456 if (ret < 0) { 1457 dev_err(&pdev->dev, 1458 "Tegra20 APB DMA OF registration failed %d\n", ret); 1459 goto err_unregister_dma_dev; 1460 } 1461 1462 dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n", 1463 cdata->nr_channels); 1464 return 0; 1465 1466 err_unregister_dma_dev: 1467 dma_async_device_unregister(&tdma->dma_dev); 1468 err_irq: 1469 while (--i >= 0) { 1470 struct tegra_dma_channel *tdc = &tdma->channels[i]; 1471 1472 free_irq(tdc->irq, tdc); 1473 tasklet_kill(&tdc->tasklet); 1474 } 1475 1476 pm_runtime_disable(&pdev->dev); 1477 if (!pm_runtime_status_suspended(&pdev->dev)) 1478 tegra_dma_runtime_suspend(&pdev->dev); 1479 return ret; 1480 } 1481 1482 static int tegra_dma_remove(struct platform_device *pdev) 1483 { 1484 struct tegra_dma *tdma = platform_get_drvdata(pdev); 1485 int i; 1486 struct tegra_dma_channel *tdc; 1487 1488 dma_async_device_unregister(&tdma->dma_dev); 1489 1490 for (i = 0; i < tdma->chip_data->nr_channels; ++i) { 1491 tdc = &tdma->channels[i]; 1492 free_irq(tdc->irq, tdc); 1493 tasklet_kill(&tdc->tasklet); 1494 } 1495 1496 pm_runtime_disable(&pdev->dev); 1497 if (!pm_runtime_status_suspended(&pdev->dev)) 1498 tegra_dma_runtime_suspend(&pdev->dev); 1499 1500 return 0; 1501 } 1502 1503 static int tegra_dma_runtime_suspend(struct device *dev) 1504 { 1505 struct tegra_dma *tdma = dev_get_drvdata(dev); 1506 int i; 1507 1508 tdma->reg_gen = tdma_read(tdma, TEGRA_APBDMA_GENERAL); 1509 for (i = 0; i < tdma->chip_data->nr_channels; i++) { 1510 struct tegra_dma_channel *tdc = &tdma->channels[i]; 1511 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg; 1512 1513 /* Only save the state of DMA channels that are in use */ 1514 if (!tdc->config_init) 1515 continue; 1516 1517 ch_reg->csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR); 1518 ch_reg->ahb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBPTR); 1519 ch_reg->apb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBPTR); 1520 ch_reg->ahb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBSEQ); 1521 ch_reg->apb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBSEQ); 1522 if (tdma->chip_data->support_separate_wcount_reg) 1523 ch_reg->wcount = tdc_read(tdc, 1524 TEGRA_APBDMA_CHAN_WCOUNT); 1525 } 1526 1527 clk_disable_unprepare(tdma->dma_clk); 1528 1529 return 0; 1530 } 1531 1532 static int tegra_dma_runtime_resume(struct device *dev) 1533 { 1534 struct tegra_dma *tdma = dev_get_drvdata(dev); 1535 int i, ret; 1536 1537 ret = clk_prepare_enable(tdma->dma_clk); 1538 if (ret < 0) { 1539 dev_err(dev, "clk_enable failed: %d\n", ret); 1540 return ret; 1541 } 1542 1543 tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen); 1544 tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); 1545 tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul); 1546 1547 for (i = 0; i < tdma->chip_data->nr_channels; i++) { 1548 struct tegra_dma_channel *tdc = &tdma->channels[i]; 1549 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg; 1550 1551 /* Only restore the state of DMA channels that are in use */ 1552 if (!tdc->config_init) 1553 continue; 1554 1555 if (tdma->chip_data->support_separate_wcount_reg) 1556 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, 1557 ch_reg->wcount); 1558 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_reg->apb_seq); 1559 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_reg->apb_ptr); 1560 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_reg->ahb_seq); 1561 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_reg->ahb_ptr); 1562 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, 1563 (ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB)); 1564 } 1565 1566 return 0; 1567 } 1568 1569 static const struct dev_pm_ops tegra_dma_dev_pm_ops = { 1570 SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume, 1571 NULL) 1572 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 1573 pm_runtime_force_resume) 1574 }; 1575 1576 static const struct of_device_id tegra_dma_of_match[] = { 1577 { 1578 .compatible = "nvidia,tegra148-apbdma", 1579 .data = &tegra148_dma_chip_data, 1580 }, { 1581 .compatible = "nvidia,tegra114-apbdma", 1582 .data = &tegra114_dma_chip_data, 1583 }, { 1584 .compatible = "nvidia,tegra30-apbdma", 1585 .data = &tegra30_dma_chip_data, 1586 }, { 1587 .compatible = "nvidia,tegra20-apbdma", 1588 .data = &tegra20_dma_chip_data, 1589 }, { 1590 }, 1591 }; 1592 MODULE_DEVICE_TABLE(of, tegra_dma_of_match); 1593 1594 static struct platform_driver tegra_dmac_driver = { 1595 .driver = { 1596 .name = "tegra-apbdma", 1597 .pm = &tegra_dma_dev_pm_ops, 1598 .of_match_table = tegra_dma_of_match, 1599 }, 1600 .probe = tegra_dma_probe, 1601 .remove = tegra_dma_remove, 1602 }; 1603 1604 module_platform_driver(tegra_dmac_driver); 1605 1606 MODULE_ALIAS("platform:tegra20-apbdma"); 1607 MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver"); 1608 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 1609 MODULE_LICENSE("GPL v2"); 1610