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