1 /* 2 * Freescale MPC85xx, MPC83xx DMA Engine support 3 * 4 * Copyright (C) 2007-2010 Freescale Semiconductor, Inc. All rights reserved. 5 * 6 * Author: 7 * Zhang Wei <wei.zhang@freescale.com>, Jul 2007 8 * Ebony Zhu <ebony.zhu@freescale.com>, May 2007 9 * 10 * Description: 11 * DMA engine driver for Freescale MPC8540 DMA controller, which is 12 * also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc. 13 * The support for MPC8349 DMA controller is also added. 14 * 15 * This driver instructs the DMA controller to issue the PCI Read Multiple 16 * command for PCI read operations, instead of using the default PCI Read Line 17 * command. Please be aware that this setting may result in read pre-fetching 18 * on some platforms. 19 * 20 * This is free software; you can redistribute it and/or modify 21 * it under the terms of the GNU General Public License as published by 22 * the Free Software Foundation; either version 2 of the License, or 23 * (at your option) any later version. 24 * 25 */ 26 27 #include <linux/init.h> 28 #include <linux/module.h> 29 #include <linux/pci.h> 30 #include <linux/slab.h> 31 #include <linux/interrupt.h> 32 #include <linux/dmaengine.h> 33 #include <linux/delay.h> 34 #include <linux/dma-mapping.h> 35 #include <linux/dmapool.h> 36 #include <linux/of_address.h> 37 #include <linux/of_irq.h> 38 #include <linux/of_platform.h> 39 #include <linux/fsldma.h> 40 #include "dmaengine.h" 41 #include "fsldma.h" 42 43 #define chan_dbg(chan, fmt, arg...) \ 44 dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg) 45 #define chan_err(chan, fmt, arg...) \ 46 dev_err(chan->dev, "%s: " fmt, chan->name, ##arg) 47 48 static const char msg_ld_oom[] = "No free memory for link descriptor"; 49 50 /* 51 * Register Helpers 52 */ 53 54 static void set_sr(struct fsldma_chan *chan, u32 val) 55 { 56 DMA_OUT(chan, &chan->regs->sr, val, 32); 57 } 58 59 static u32 get_sr(struct fsldma_chan *chan) 60 { 61 return DMA_IN(chan, &chan->regs->sr, 32); 62 } 63 64 static void set_mr(struct fsldma_chan *chan, u32 val) 65 { 66 DMA_OUT(chan, &chan->regs->mr, val, 32); 67 } 68 69 static u32 get_mr(struct fsldma_chan *chan) 70 { 71 return DMA_IN(chan, &chan->regs->mr, 32); 72 } 73 74 static void set_cdar(struct fsldma_chan *chan, dma_addr_t addr) 75 { 76 DMA_OUT(chan, &chan->regs->cdar, addr | FSL_DMA_SNEN, 64); 77 } 78 79 static dma_addr_t get_cdar(struct fsldma_chan *chan) 80 { 81 return DMA_IN(chan, &chan->regs->cdar, 64) & ~FSL_DMA_SNEN; 82 } 83 84 static void set_bcr(struct fsldma_chan *chan, u32 val) 85 { 86 DMA_OUT(chan, &chan->regs->bcr, val, 32); 87 } 88 89 static u32 get_bcr(struct fsldma_chan *chan) 90 { 91 return DMA_IN(chan, &chan->regs->bcr, 32); 92 } 93 94 /* 95 * Descriptor Helpers 96 */ 97 98 static void set_desc_cnt(struct fsldma_chan *chan, 99 struct fsl_dma_ld_hw *hw, u32 count) 100 { 101 hw->count = CPU_TO_DMA(chan, count, 32); 102 } 103 104 static void set_desc_src(struct fsldma_chan *chan, 105 struct fsl_dma_ld_hw *hw, dma_addr_t src) 106 { 107 u64 snoop_bits; 108 109 snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) 110 ? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0; 111 hw->src_addr = CPU_TO_DMA(chan, snoop_bits | src, 64); 112 } 113 114 static void set_desc_dst(struct fsldma_chan *chan, 115 struct fsl_dma_ld_hw *hw, dma_addr_t dst) 116 { 117 u64 snoop_bits; 118 119 snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) 120 ? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0; 121 hw->dst_addr = CPU_TO_DMA(chan, snoop_bits | dst, 64); 122 } 123 124 static void set_desc_next(struct fsldma_chan *chan, 125 struct fsl_dma_ld_hw *hw, dma_addr_t next) 126 { 127 u64 snoop_bits; 128 129 snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX) 130 ? FSL_DMA_SNEN : 0; 131 hw->next_ln_addr = CPU_TO_DMA(chan, snoop_bits | next, 64); 132 } 133 134 static void set_ld_eol(struct fsldma_chan *chan, struct fsl_desc_sw *desc) 135 { 136 u64 snoop_bits; 137 138 snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX) 139 ? FSL_DMA_SNEN : 0; 140 141 desc->hw.next_ln_addr = CPU_TO_DMA(chan, 142 DMA_TO_CPU(chan, desc->hw.next_ln_addr, 64) | FSL_DMA_EOL 143 | snoop_bits, 64); 144 } 145 146 /* 147 * DMA Engine Hardware Control Helpers 148 */ 149 150 static void dma_init(struct fsldma_chan *chan) 151 { 152 /* Reset the channel */ 153 set_mr(chan, 0); 154 155 switch (chan->feature & FSL_DMA_IP_MASK) { 156 case FSL_DMA_IP_85XX: 157 /* Set the channel to below modes: 158 * EIE - Error interrupt enable 159 * EOLNIE - End of links interrupt enable 160 * BWC - Bandwidth sharing among channels 161 */ 162 set_mr(chan, FSL_DMA_MR_BWC | FSL_DMA_MR_EIE 163 | FSL_DMA_MR_EOLNIE); 164 break; 165 case FSL_DMA_IP_83XX: 166 /* Set the channel to below modes: 167 * EOTIE - End-of-transfer interrupt enable 168 * PRC_RM - PCI read multiple 169 */ 170 set_mr(chan, FSL_DMA_MR_EOTIE | FSL_DMA_MR_PRC_RM); 171 break; 172 } 173 } 174 175 static int dma_is_idle(struct fsldma_chan *chan) 176 { 177 u32 sr = get_sr(chan); 178 return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH); 179 } 180 181 /* 182 * Start the DMA controller 183 * 184 * Preconditions: 185 * - the CDAR register must point to the start descriptor 186 * - the MRn[CS] bit must be cleared 187 */ 188 static void dma_start(struct fsldma_chan *chan) 189 { 190 u32 mode; 191 192 mode = get_mr(chan); 193 194 if (chan->feature & FSL_DMA_CHAN_PAUSE_EXT) { 195 set_bcr(chan, 0); 196 mode |= FSL_DMA_MR_EMP_EN; 197 } else { 198 mode &= ~FSL_DMA_MR_EMP_EN; 199 } 200 201 if (chan->feature & FSL_DMA_CHAN_START_EXT) { 202 mode |= FSL_DMA_MR_EMS_EN; 203 } else { 204 mode &= ~FSL_DMA_MR_EMS_EN; 205 mode |= FSL_DMA_MR_CS; 206 } 207 208 set_mr(chan, mode); 209 } 210 211 static void dma_halt(struct fsldma_chan *chan) 212 { 213 u32 mode; 214 int i; 215 216 /* read the mode register */ 217 mode = get_mr(chan); 218 219 /* 220 * The 85xx controller supports channel abort, which will stop 221 * the current transfer. On 83xx, this bit is the transfer error 222 * mask bit, which should not be changed. 223 */ 224 if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) { 225 mode |= FSL_DMA_MR_CA; 226 set_mr(chan, mode); 227 228 mode &= ~FSL_DMA_MR_CA; 229 } 230 231 /* stop the DMA controller */ 232 mode &= ~(FSL_DMA_MR_CS | FSL_DMA_MR_EMS_EN); 233 set_mr(chan, mode); 234 235 /* wait for the DMA controller to become idle */ 236 for (i = 0; i < 100; i++) { 237 if (dma_is_idle(chan)) 238 return; 239 240 udelay(10); 241 } 242 243 if (!dma_is_idle(chan)) 244 chan_err(chan, "DMA halt timeout!\n"); 245 } 246 247 /** 248 * fsl_chan_set_src_loop_size - Set source address hold transfer size 249 * @chan : Freescale DMA channel 250 * @size : Address loop size, 0 for disable loop 251 * 252 * The set source address hold transfer size. The source 253 * address hold or loop transfer size is when the DMA transfer 254 * data from source address (SA), if the loop size is 4, the DMA will 255 * read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA, 256 * SA + 1 ... and so on. 257 */ 258 static void fsl_chan_set_src_loop_size(struct fsldma_chan *chan, int size) 259 { 260 u32 mode; 261 262 mode = get_mr(chan); 263 264 switch (size) { 265 case 0: 266 mode &= ~FSL_DMA_MR_SAHE; 267 break; 268 case 1: 269 case 2: 270 case 4: 271 case 8: 272 mode |= FSL_DMA_MR_SAHE | (__ilog2(size) << 14); 273 break; 274 } 275 276 set_mr(chan, mode); 277 } 278 279 /** 280 * fsl_chan_set_dst_loop_size - Set destination address hold transfer size 281 * @chan : Freescale DMA channel 282 * @size : Address loop size, 0 for disable loop 283 * 284 * The set destination address hold transfer size. The destination 285 * address hold or loop transfer size is when the DMA transfer 286 * data to destination address (TA), if the loop size is 4, the DMA will 287 * write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA, 288 * TA + 1 ... and so on. 289 */ 290 static void fsl_chan_set_dst_loop_size(struct fsldma_chan *chan, int size) 291 { 292 u32 mode; 293 294 mode = get_mr(chan); 295 296 switch (size) { 297 case 0: 298 mode &= ~FSL_DMA_MR_DAHE; 299 break; 300 case 1: 301 case 2: 302 case 4: 303 case 8: 304 mode |= FSL_DMA_MR_DAHE | (__ilog2(size) << 16); 305 break; 306 } 307 308 set_mr(chan, mode); 309 } 310 311 /** 312 * fsl_chan_set_request_count - Set DMA Request Count for external control 313 * @chan : Freescale DMA channel 314 * @size : Number of bytes to transfer in a single request 315 * 316 * The Freescale DMA channel can be controlled by the external signal DREQ#. 317 * The DMA request count is how many bytes are allowed to transfer before 318 * pausing the channel, after which a new assertion of DREQ# resumes channel 319 * operation. 320 * 321 * A size of 0 disables external pause control. The maximum size is 1024. 322 */ 323 static void fsl_chan_set_request_count(struct fsldma_chan *chan, int size) 324 { 325 u32 mode; 326 327 BUG_ON(size > 1024); 328 329 mode = get_mr(chan); 330 mode |= (__ilog2(size) << 24) & 0x0f000000; 331 332 set_mr(chan, mode); 333 } 334 335 /** 336 * fsl_chan_toggle_ext_pause - Toggle channel external pause status 337 * @chan : Freescale DMA channel 338 * @enable : 0 is disabled, 1 is enabled. 339 * 340 * The Freescale DMA channel can be controlled by the external signal DREQ#. 341 * The DMA Request Count feature should be used in addition to this feature 342 * to set the number of bytes to transfer before pausing the channel. 343 */ 344 static void fsl_chan_toggle_ext_pause(struct fsldma_chan *chan, int enable) 345 { 346 if (enable) 347 chan->feature |= FSL_DMA_CHAN_PAUSE_EXT; 348 else 349 chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT; 350 } 351 352 /** 353 * fsl_chan_toggle_ext_start - Toggle channel external start status 354 * @chan : Freescale DMA channel 355 * @enable : 0 is disabled, 1 is enabled. 356 * 357 * If enable the external start, the channel can be started by an 358 * external DMA start pin. So the dma_start() does not start the 359 * transfer immediately. The DMA channel will wait for the 360 * control pin asserted. 361 */ 362 static void fsl_chan_toggle_ext_start(struct fsldma_chan *chan, int enable) 363 { 364 if (enable) 365 chan->feature |= FSL_DMA_CHAN_START_EXT; 366 else 367 chan->feature &= ~FSL_DMA_CHAN_START_EXT; 368 } 369 370 int fsl_dma_external_start(struct dma_chan *dchan, int enable) 371 { 372 struct fsldma_chan *chan; 373 374 if (!dchan) 375 return -EINVAL; 376 377 chan = to_fsl_chan(dchan); 378 379 fsl_chan_toggle_ext_start(chan, enable); 380 return 0; 381 } 382 EXPORT_SYMBOL_GPL(fsl_dma_external_start); 383 384 static void append_ld_queue(struct fsldma_chan *chan, struct fsl_desc_sw *desc) 385 { 386 struct fsl_desc_sw *tail = to_fsl_desc(chan->ld_pending.prev); 387 388 if (list_empty(&chan->ld_pending)) 389 goto out_splice; 390 391 /* 392 * Add the hardware descriptor to the chain of hardware descriptors 393 * that already exists in memory. 394 * 395 * This will un-set the EOL bit of the existing transaction, and the 396 * last link in this transaction will become the EOL descriptor. 397 */ 398 set_desc_next(chan, &tail->hw, desc->async_tx.phys); 399 400 /* 401 * Add the software descriptor and all children to the list 402 * of pending transactions 403 */ 404 out_splice: 405 list_splice_tail_init(&desc->tx_list, &chan->ld_pending); 406 } 407 408 static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx) 409 { 410 struct fsldma_chan *chan = to_fsl_chan(tx->chan); 411 struct fsl_desc_sw *desc = tx_to_fsl_desc(tx); 412 struct fsl_desc_sw *child; 413 dma_cookie_t cookie = -EINVAL; 414 415 spin_lock_bh(&chan->desc_lock); 416 417 #ifdef CONFIG_PM 418 if (unlikely(chan->pm_state != RUNNING)) { 419 chan_dbg(chan, "cannot submit due to suspend\n"); 420 spin_unlock_bh(&chan->desc_lock); 421 return -1; 422 } 423 #endif 424 425 /* 426 * assign cookies to all of the software descriptors 427 * that make up this transaction 428 */ 429 list_for_each_entry(child, &desc->tx_list, node) { 430 cookie = dma_cookie_assign(&child->async_tx); 431 } 432 433 /* put this transaction onto the tail of the pending queue */ 434 append_ld_queue(chan, desc); 435 436 spin_unlock_bh(&chan->desc_lock); 437 438 return cookie; 439 } 440 441 /** 442 * fsl_dma_free_descriptor - Free descriptor from channel's DMA pool. 443 * @chan : Freescale DMA channel 444 * @desc: descriptor to be freed 445 */ 446 static void fsl_dma_free_descriptor(struct fsldma_chan *chan, 447 struct fsl_desc_sw *desc) 448 { 449 list_del(&desc->node); 450 chan_dbg(chan, "LD %p free\n", desc); 451 dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys); 452 } 453 454 /** 455 * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool. 456 * @chan : Freescale DMA channel 457 * 458 * Return - The descriptor allocated. NULL for failed. 459 */ 460 static struct fsl_desc_sw *fsl_dma_alloc_descriptor(struct fsldma_chan *chan) 461 { 462 struct fsl_desc_sw *desc; 463 dma_addr_t pdesc; 464 465 desc = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &pdesc); 466 if (!desc) { 467 chan_dbg(chan, "out of memory for link descriptor\n"); 468 return NULL; 469 } 470 471 memset(desc, 0, sizeof(*desc)); 472 INIT_LIST_HEAD(&desc->tx_list); 473 dma_async_tx_descriptor_init(&desc->async_tx, &chan->common); 474 desc->async_tx.tx_submit = fsl_dma_tx_submit; 475 desc->async_tx.phys = pdesc; 476 477 chan_dbg(chan, "LD %p allocated\n", desc); 478 479 return desc; 480 } 481 482 /** 483 * fsldma_clean_completed_descriptor - free all descriptors which 484 * has been completed and acked 485 * @chan: Freescale DMA channel 486 * 487 * This function is used on all completed and acked descriptors. 488 * All descriptors should only be freed in this function. 489 */ 490 static void fsldma_clean_completed_descriptor(struct fsldma_chan *chan) 491 { 492 struct fsl_desc_sw *desc, *_desc; 493 494 /* Run the callback for each descriptor, in order */ 495 list_for_each_entry_safe(desc, _desc, &chan->ld_completed, node) 496 if (async_tx_test_ack(&desc->async_tx)) 497 fsl_dma_free_descriptor(chan, desc); 498 } 499 500 /** 501 * fsldma_run_tx_complete_actions - cleanup a single link descriptor 502 * @chan: Freescale DMA channel 503 * @desc: descriptor to cleanup and free 504 * @cookie: Freescale DMA transaction identifier 505 * 506 * This function is used on a descriptor which has been executed by the DMA 507 * controller. It will run any callbacks, submit any dependencies. 508 */ 509 static dma_cookie_t fsldma_run_tx_complete_actions(struct fsldma_chan *chan, 510 struct fsl_desc_sw *desc, dma_cookie_t cookie) 511 { 512 struct dma_async_tx_descriptor *txd = &desc->async_tx; 513 dma_cookie_t ret = cookie; 514 515 BUG_ON(txd->cookie < 0); 516 517 if (txd->cookie > 0) { 518 ret = txd->cookie; 519 520 /* Run the link descriptor callback function */ 521 if (txd->callback) { 522 chan_dbg(chan, "LD %p callback\n", desc); 523 txd->callback(txd->callback_param); 524 } 525 } 526 527 /* Run any dependencies */ 528 dma_run_dependencies(txd); 529 530 return ret; 531 } 532 533 /** 534 * fsldma_clean_running_descriptor - move the completed descriptor from 535 * ld_running to ld_completed 536 * @chan: Freescale DMA channel 537 * @desc: the descriptor which is completed 538 * 539 * Free the descriptor directly if acked by async_tx api, or move it to 540 * queue ld_completed. 541 */ 542 static void fsldma_clean_running_descriptor(struct fsldma_chan *chan, 543 struct fsl_desc_sw *desc) 544 { 545 /* Remove from the list of transactions */ 546 list_del(&desc->node); 547 548 /* 549 * the client is allowed to attach dependent operations 550 * until 'ack' is set 551 */ 552 if (!async_tx_test_ack(&desc->async_tx)) { 553 /* 554 * Move this descriptor to the list of descriptors which is 555 * completed, but still awaiting the 'ack' bit to be set. 556 */ 557 list_add_tail(&desc->node, &chan->ld_completed); 558 return; 559 } 560 561 dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys); 562 } 563 564 /** 565 * fsl_chan_xfer_ld_queue - transfer any pending transactions 566 * @chan : Freescale DMA channel 567 * 568 * HARDWARE STATE: idle 569 * LOCKING: must hold chan->desc_lock 570 */ 571 static void fsl_chan_xfer_ld_queue(struct fsldma_chan *chan) 572 { 573 struct fsl_desc_sw *desc; 574 575 /* 576 * If the list of pending descriptors is empty, then we 577 * don't need to do any work at all 578 */ 579 if (list_empty(&chan->ld_pending)) { 580 chan_dbg(chan, "no pending LDs\n"); 581 return; 582 } 583 584 /* 585 * The DMA controller is not idle, which means that the interrupt 586 * handler will start any queued transactions when it runs after 587 * this transaction finishes 588 */ 589 if (!chan->idle) { 590 chan_dbg(chan, "DMA controller still busy\n"); 591 return; 592 } 593 594 /* 595 * If there are some link descriptors which have not been 596 * transferred, we need to start the controller 597 */ 598 599 /* 600 * Move all elements from the queue of pending transactions 601 * onto the list of running transactions 602 */ 603 chan_dbg(chan, "idle, starting controller\n"); 604 desc = list_first_entry(&chan->ld_pending, struct fsl_desc_sw, node); 605 list_splice_tail_init(&chan->ld_pending, &chan->ld_running); 606 607 /* 608 * The 85xx DMA controller doesn't clear the channel start bit 609 * automatically at the end of a transfer. Therefore we must clear 610 * it in software before starting the transfer. 611 */ 612 if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) { 613 u32 mode; 614 615 mode = get_mr(chan); 616 mode &= ~FSL_DMA_MR_CS; 617 set_mr(chan, mode); 618 } 619 620 /* 621 * Program the descriptor's address into the DMA controller, 622 * then start the DMA transaction 623 */ 624 set_cdar(chan, desc->async_tx.phys); 625 get_cdar(chan); 626 627 dma_start(chan); 628 chan->idle = false; 629 } 630 631 /** 632 * fsldma_cleanup_descriptors - cleanup link descriptors which are completed 633 * and move them to ld_completed to free until flag 'ack' is set 634 * @chan: Freescale DMA channel 635 * 636 * This function is used on descriptors which have been executed by the DMA 637 * controller. It will run any callbacks, submit any dependencies, then 638 * free these descriptors if flag 'ack' is set. 639 */ 640 static void fsldma_cleanup_descriptors(struct fsldma_chan *chan) 641 { 642 struct fsl_desc_sw *desc, *_desc; 643 dma_cookie_t cookie = 0; 644 dma_addr_t curr_phys = get_cdar(chan); 645 int seen_current = 0; 646 647 fsldma_clean_completed_descriptor(chan); 648 649 /* Run the callback for each descriptor, in order */ 650 list_for_each_entry_safe(desc, _desc, &chan->ld_running, node) { 651 /* 652 * do not advance past the current descriptor loaded into the 653 * hardware channel, subsequent descriptors are either in 654 * process or have not been submitted 655 */ 656 if (seen_current) 657 break; 658 659 /* 660 * stop the search if we reach the current descriptor and the 661 * channel is busy 662 */ 663 if (desc->async_tx.phys == curr_phys) { 664 seen_current = 1; 665 if (!dma_is_idle(chan)) 666 break; 667 } 668 669 cookie = fsldma_run_tx_complete_actions(chan, desc, cookie); 670 671 fsldma_clean_running_descriptor(chan, desc); 672 } 673 674 /* 675 * Start any pending transactions automatically 676 * 677 * In the ideal case, we keep the DMA controller busy while we go 678 * ahead and free the descriptors below. 679 */ 680 fsl_chan_xfer_ld_queue(chan); 681 682 if (cookie > 0) 683 chan->common.completed_cookie = cookie; 684 } 685 686 /** 687 * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel. 688 * @chan : Freescale DMA channel 689 * 690 * This function will create a dma pool for descriptor allocation. 691 * 692 * Return - The number of descriptors allocated. 693 */ 694 static int fsl_dma_alloc_chan_resources(struct dma_chan *dchan) 695 { 696 struct fsldma_chan *chan = to_fsl_chan(dchan); 697 698 /* Has this channel already been allocated? */ 699 if (chan->desc_pool) 700 return 1; 701 702 /* 703 * We need the descriptor to be aligned to 32bytes 704 * for meeting FSL DMA specification requirement. 705 */ 706 chan->desc_pool = dma_pool_create(chan->name, chan->dev, 707 sizeof(struct fsl_desc_sw), 708 __alignof__(struct fsl_desc_sw), 0); 709 if (!chan->desc_pool) { 710 chan_err(chan, "unable to allocate descriptor pool\n"); 711 return -ENOMEM; 712 } 713 714 /* there is at least one descriptor free to be allocated */ 715 return 1; 716 } 717 718 /** 719 * fsldma_free_desc_list - Free all descriptors in a queue 720 * @chan: Freescae DMA channel 721 * @list: the list to free 722 * 723 * LOCKING: must hold chan->desc_lock 724 */ 725 static void fsldma_free_desc_list(struct fsldma_chan *chan, 726 struct list_head *list) 727 { 728 struct fsl_desc_sw *desc, *_desc; 729 730 list_for_each_entry_safe(desc, _desc, list, node) 731 fsl_dma_free_descriptor(chan, desc); 732 } 733 734 static void fsldma_free_desc_list_reverse(struct fsldma_chan *chan, 735 struct list_head *list) 736 { 737 struct fsl_desc_sw *desc, *_desc; 738 739 list_for_each_entry_safe_reverse(desc, _desc, list, node) 740 fsl_dma_free_descriptor(chan, desc); 741 } 742 743 /** 744 * fsl_dma_free_chan_resources - Free all resources of the channel. 745 * @chan : Freescale DMA channel 746 */ 747 static void fsl_dma_free_chan_resources(struct dma_chan *dchan) 748 { 749 struct fsldma_chan *chan = to_fsl_chan(dchan); 750 751 chan_dbg(chan, "free all channel resources\n"); 752 spin_lock_bh(&chan->desc_lock); 753 fsldma_cleanup_descriptors(chan); 754 fsldma_free_desc_list(chan, &chan->ld_pending); 755 fsldma_free_desc_list(chan, &chan->ld_running); 756 fsldma_free_desc_list(chan, &chan->ld_completed); 757 spin_unlock_bh(&chan->desc_lock); 758 759 dma_pool_destroy(chan->desc_pool); 760 chan->desc_pool = NULL; 761 } 762 763 static struct dma_async_tx_descriptor * 764 fsl_dma_prep_memcpy(struct dma_chan *dchan, 765 dma_addr_t dma_dst, dma_addr_t dma_src, 766 size_t len, unsigned long flags) 767 { 768 struct fsldma_chan *chan; 769 struct fsl_desc_sw *first = NULL, *prev = NULL, *new; 770 size_t copy; 771 772 if (!dchan) 773 return NULL; 774 775 if (!len) 776 return NULL; 777 778 chan = to_fsl_chan(dchan); 779 780 do { 781 782 /* Allocate the link descriptor from DMA pool */ 783 new = fsl_dma_alloc_descriptor(chan); 784 if (!new) { 785 chan_err(chan, "%s\n", msg_ld_oom); 786 goto fail; 787 } 788 789 copy = min(len, (size_t)FSL_DMA_BCR_MAX_CNT); 790 791 set_desc_cnt(chan, &new->hw, copy); 792 set_desc_src(chan, &new->hw, dma_src); 793 set_desc_dst(chan, &new->hw, dma_dst); 794 795 if (!first) 796 first = new; 797 else 798 set_desc_next(chan, &prev->hw, new->async_tx.phys); 799 800 new->async_tx.cookie = 0; 801 async_tx_ack(&new->async_tx); 802 803 prev = new; 804 len -= copy; 805 dma_src += copy; 806 dma_dst += copy; 807 808 /* Insert the link descriptor to the LD ring */ 809 list_add_tail(&new->node, &first->tx_list); 810 } while (len); 811 812 new->async_tx.flags = flags; /* client is in control of this ack */ 813 new->async_tx.cookie = -EBUSY; 814 815 /* Set End-of-link to the last link descriptor of new list */ 816 set_ld_eol(chan, new); 817 818 return &first->async_tx; 819 820 fail: 821 if (!first) 822 return NULL; 823 824 fsldma_free_desc_list_reverse(chan, &first->tx_list); 825 return NULL; 826 } 827 828 static struct dma_async_tx_descriptor *fsl_dma_prep_sg(struct dma_chan *dchan, 829 struct scatterlist *dst_sg, unsigned int dst_nents, 830 struct scatterlist *src_sg, unsigned int src_nents, 831 unsigned long flags) 832 { 833 struct fsl_desc_sw *first = NULL, *prev = NULL, *new = NULL; 834 struct fsldma_chan *chan = to_fsl_chan(dchan); 835 size_t dst_avail, src_avail; 836 dma_addr_t dst, src; 837 size_t len; 838 839 /* basic sanity checks */ 840 if (dst_nents == 0 || src_nents == 0) 841 return NULL; 842 843 if (dst_sg == NULL || src_sg == NULL) 844 return NULL; 845 846 /* 847 * TODO: should we check that both scatterlists have the same 848 * TODO: number of bytes in total? Is that really an error? 849 */ 850 851 /* get prepared for the loop */ 852 dst_avail = sg_dma_len(dst_sg); 853 src_avail = sg_dma_len(src_sg); 854 855 /* run until we are out of scatterlist entries */ 856 while (true) { 857 858 /* create the largest transaction possible */ 859 len = min_t(size_t, src_avail, dst_avail); 860 len = min_t(size_t, len, FSL_DMA_BCR_MAX_CNT); 861 if (len == 0) 862 goto fetch; 863 864 dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail; 865 src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail; 866 867 /* allocate and populate the descriptor */ 868 new = fsl_dma_alloc_descriptor(chan); 869 if (!new) { 870 chan_err(chan, "%s\n", msg_ld_oom); 871 goto fail; 872 } 873 874 set_desc_cnt(chan, &new->hw, len); 875 set_desc_src(chan, &new->hw, src); 876 set_desc_dst(chan, &new->hw, dst); 877 878 if (!first) 879 first = new; 880 else 881 set_desc_next(chan, &prev->hw, new->async_tx.phys); 882 883 new->async_tx.cookie = 0; 884 async_tx_ack(&new->async_tx); 885 prev = new; 886 887 /* Insert the link descriptor to the LD ring */ 888 list_add_tail(&new->node, &first->tx_list); 889 890 /* update metadata */ 891 dst_avail -= len; 892 src_avail -= len; 893 894 fetch: 895 /* fetch the next dst scatterlist entry */ 896 if (dst_avail == 0) { 897 898 /* no more entries: we're done */ 899 if (dst_nents == 0) 900 break; 901 902 /* fetch the next entry: if there are no more: done */ 903 dst_sg = sg_next(dst_sg); 904 if (dst_sg == NULL) 905 break; 906 907 dst_nents--; 908 dst_avail = sg_dma_len(dst_sg); 909 } 910 911 /* fetch the next src scatterlist entry */ 912 if (src_avail == 0) { 913 914 /* no more entries: we're done */ 915 if (src_nents == 0) 916 break; 917 918 /* fetch the next entry: if there are no more: done */ 919 src_sg = sg_next(src_sg); 920 if (src_sg == NULL) 921 break; 922 923 src_nents--; 924 src_avail = sg_dma_len(src_sg); 925 } 926 } 927 928 new->async_tx.flags = flags; /* client is in control of this ack */ 929 new->async_tx.cookie = -EBUSY; 930 931 /* Set End-of-link to the last link descriptor of new list */ 932 set_ld_eol(chan, new); 933 934 return &first->async_tx; 935 936 fail: 937 if (!first) 938 return NULL; 939 940 fsldma_free_desc_list_reverse(chan, &first->tx_list); 941 return NULL; 942 } 943 944 /** 945 * fsl_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction 946 * @chan: DMA channel 947 * @sgl: scatterlist to transfer to/from 948 * @sg_len: number of entries in @scatterlist 949 * @direction: DMA direction 950 * @flags: DMAEngine flags 951 * @context: transaction context (ignored) 952 * 953 * Prepare a set of descriptors for a DMA_SLAVE transaction. Following the 954 * DMA_SLAVE API, this gets the device-specific information from the 955 * chan->private variable. 956 */ 957 static struct dma_async_tx_descriptor *fsl_dma_prep_slave_sg( 958 struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len, 959 enum dma_transfer_direction direction, unsigned long flags, 960 void *context) 961 { 962 /* 963 * This operation is not supported on the Freescale DMA controller 964 * 965 * However, we need to provide the function pointer to allow the 966 * device_control() method to work. 967 */ 968 return NULL; 969 } 970 971 static int fsl_dma_device_control(struct dma_chan *dchan, 972 enum dma_ctrl_cmd cmd, unsigned long arg) 973 { 974 struct dma_slave_config *config; 975 struct fsldma_chan *chan; 976 int size; 977 978 if (!dchan) 979 return -EINVAL; 980 981 chan = to_fsl_chan(dchan); 982 983 switch (cmd) { 984 case DMA_TERMINATE_ALL: 985 spin_lock_bh(&chan->desc_lock); 986 987 /* Halt the DMA engine */ 988 dma_halt(chan); 989 990 /* Remove and free all of the descriptors in the LD queue */ 991 fsldma_free_desc_list(chan, &chan->ld_pending); 992 fsldma_free_desc_list(chan, &chan->ld_running); 993 fsldma_free_desc_list(chan, &chan->ld_completed); 994 chan->idle = true; 995 996 spin_unlock_bh(&chan->desc_lock); 997 return 0; 998 999 case DMA_SLAVE_CONFIG: 1000 config = (struct dma_slave_config *)arg; 1001 1002 /* make sure the channel supports setting burst size */ 1003 if (!chan->set_request_count) 1004 return -ENXIO; 1005 1006 /* we set the controller burst size depending on direction */ 1007 if (config->direction == DMA_MEM_TO_DEV) 1008 size = config->dst_addr_width * config->dst_maxburst; 1009 else 1010 size = config->src_addr_width * config->src_maxburst; 1011 1012 chan->set_request_count(chan, size); 1013 return 0; 1014 1015 default: 1016 return -ENXIO; 1017 } 1018 1019 return 0; 1020 } 1021 1022 /** 1023 * fsl_dma_memcpy_issue_pending - Issue the DMA start command 1024 * @chan : Freescale DMA channel 1025 */ 1026 static void fsl_dma_memcpy_issue_pending(struct dma_chan *dchan) 1027 { 1028 struct fsldma_chan *chan = to_fsl_chan(dchan); 1029 1030 spin_lock_bh(&chan->desc_lock); 1031 fsl_chan_xfer_ld_queue(chan); 1032 spin_unlock_bh(&chan->desc_lock); 1033 } 1034 1035 /** 1036 * fsl_tx_status - Determine the DMA status 1037 * @chan : Freescale DMA channel 1038 */ 1039 static enum dma_status fsl_tx_status(struct dma_chan *dchan, 1040 dma_cookie_t cookie, 1041 struct dma_tx_state *txstate) 1042 { 1043 struct fsldma_chan *chan = to_fsl_chan(dchan); 1044 enum dma_status ret; 1045 1046 ret = dma_cookie_status(dchan, cookie, txstate); 1047 if (ret == DMA_COMPLETE) 1048 return ret; 1049 1050 spin_lock_bh(&chan->desc_lock); 1051 fsldma_cleanup_descriptors(chan); 1052 spin_unlock_bh(&chan->desc_lock); 1053 1054 return dma_cookie_status(dchan, cookie, txstate); 1055 } 1056 1057 /*----------------------------------------------------------------------------*/ 1058 /* Interrupt Handling */ 1059 /*----------------------------------------------------------------------------*/ 1060 1061 static irqreturn_t fsldma_chan_irq(int irq, void *data) 1062 { 1063 struct fsldma_chan *chan = data; 1064 u32 stat; 1065 1066 /* save and clear the status register */ 1067 stat = get_sr(chan); 1068 set_sr(chan, stat); 1069 chan_dbg(chan, "irq: stat = 0x%x\n", stat); 1070 1071 /* check that this was really our device */ 1072 stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH); 1073 if (!stat) 1074 return IRQ_NONE; 1075 1076 if (stat & FSL_DMA_SR_TE) 1077 chan_err(chan, "Transfer Error!\n"); 1078 1079 /* 1080 * Programming Error 1081 * The DMA_INTERRUPT async_tx is a NULL transfer, which will 1082 * trigger a PE interrupt. 1083 */ 1084 if (stat & FSL_DMA_SR_PE) { 1085 chan_dbg(chan, "irq: Programming Error INT\n"); 1086 stat &= ~FSL_DMA_SR_PE; 1087 if (get_bcr(chan) != 0) 1088 chan_err(chan, "Programming Error!\n"); 1089 } 1090 1091 /* 1092 * For MPC8349, EOCDI event need to update cookie 1093 * and start the next transfer if it exist. 1094 */ 1095 if (stat & FSL_DMA_SR_EOCDI) { 1096 chan_dbg(chan, "irq: End-of-Chain link INT\n"); 1097 stat &= ~FSL_DMA_SR_EOCDI; 1098 } 1099 1100 /* 1101 * If it current transfer is the end-of-transfer, 1102 * we should clear the Channel Start bit for 1103 * prepare next transfer. 1104 */ 1105 if (stat & FSL_DMA_SR_EOLNI) { 1106 chan_dbg(chan, "irq: End-of-link INT\n"); 1107 stat &= ~FSL_DMA_SR_EOLNI; 1108 } 1109 1110 /* check that the DMA controller is really idle */ 1111 if (!dma_is_idle(chan)) 1112 chan_err(chan, "irq: controller not idle!\n"); 1113 1114 /* check that we handled all of the bits */ 1115 if (stat) 1116 chan_err(chan, "irq: unhandled sr 0x%08x\n", stat); 1117 1118 /* 1119 * Schedule the tasklet to handle all cleanup of the current 1120 * transaction. It will start a new transaction if there is 1121 * one pending. 1122 */ 1123 tasklet_schedule(&chan->tasklet); 1124 chan_dbg(chan, "irq: Exit\n"); 1125 return IRQ_HANDLED; 1126 } 1127 1128 static void dma_do_tasklet(unsigned long data) 1129 { 1130 struct fsldma_chan *chan = (struct fsldma_chan *)data; 1131 1132 chan_dbg(chan, "tasklet entry\n"); 1133 1134 spin_lock_bh(&chan->desc_lock); 1135 1136 /* the hardware is now idle and ready for more */ 1137 chan->idle = true; 1138 1139 /* Run all cleanup for descriptors which have been completed */ 1140 fsldma_cleanup_descriptors(chan); 1141 1142 spin_unlock_bh(&chan->desc_lock); 1143 1144 chan_dbg(chan, "tasklet exit\n"); 1145 } 1146 1147 static irqreturn_t fsldma_ctrl_irq(int irq, void *data) 1148 { 1149 struct fsldma_device *fdev = data; 1150 struct fsldma_chan *chan; 1151 unsigned int handled = 0; 1152 u32 gsr, mask; 1153 int i; 1154 1155 gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs) 1156 : in_le32(fdev->regs); 1157 mask = 0xff000000; 1158 dev_dbg(fdev->dev, "IRQ: gsr 0x%.8x\n", gsr); 1159 1160 for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { 1161 chan = fdev->chan[i]; 1162 if (!chan) 1163 continue; 1164 1165 if (gsr & mask) { 1166 dev_dbg(fdev->dev, "IRQ: chan %d\n", chan->id); 1167 fsldma_chan_irq(irq, chan); 1168 handled++; 1169 } 1170 1171 gsr &= ~mask; 1172 mask >>= 8; 1173 } 1174 1175 return IRQ_RETVAL(handled); 1176 } 1177 1178 static void fsldma_free_irqs(struct fsldma_device *fdev) 1179 { 1180 struct fsldma_chan *chan; 1181 int i; 1182 1183 if (fdev->irq != NO_IRQ) { 1184 dev_dbg(fdev->dev, "free per-controller IRQ\n"); 1185 free_irq(fdev->irq, fdev); 1186 return; 1187 } 1188 1189 for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { 1190 chan = fdev->chan[i]; 1191 if (chan && chan->irq != NO_IRQ) { 1192 chan_dbg(chan, "free per-channel IRQ\n"); 1193 free_irq(chan->irq, chan); 1194 } 1195 } 1196 } 1197 1198 static int fsldma_request_irqs(struct fsldma_device *fdev) 1199 { 1200 struct fsldma_chan *chan; 1201 int ret; 1202 int i; 1203 1204 /* if we have a per-controller IRQ, use that */ 1205 if (fdev->irq != NO_IRQ) { 1206 dev_dbg(fdev->dev, "request per-controller IRQ\n"); 1207 ret = request_irq(fdev->irq, fsldma_ctrl_irq, IRQF_SHARED, 1208 "fsldma-controller", fdev); 1209 return ret; 1210 } 1211 1212 /* no per-controller IRQ, use the per-channel IRQs */ 1213 for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { 1214 chan = fdev->chan[i]; 1215 if (!chan) 1216 continue; 1217 1218 if (chan->irq == NO_IRQ) { 1219 chan_err(chan, "interrupts property missing in device tree\n"); 1220 ret = -ENODEV; 1221 goto out_unwind; 1222 } 1223 1224 chan_dbg(chan, "request per-channel IRQ\n"); 1225 ret = request_irq(chan->irq, fsldma_chan_irq, IRQF_SHARED, 1226 "fsldma-chan", chan); 1227 if (ret) { 1228 chan_err(chan, "unable to request per-channel IRQ\n"); 1229 goto out_unwind; 1230 } 1231 } 1232 1233 return 0; 1234 1235 out_unwind: 1236 for (/* none */; i >= 0; i--) { 1237 chan = fdev->chan[i]; 1238 if (!chan) 1239 continue; 1240 1241 if (chan->irq == NO_IRQ) 1242 continue; 1243 1244 free_irq(chan->irq, chan); 1245 } 1246 1247 return ret; 1248 } 1249 1250 /*----------------------------------------------------------------------------*/ 1251 /* OpenFirmware Subsystem */ 1252 /*----------------------------------------------------------------------------*/ 1253 1254 static int fsl_dma_chan_probe(struct fsldma_device *fdev, 1255 struct device_node *node, u32 feature, const char *compatible) 1256 { 1257 struct fsldma_chan *chan; 1258 struct resource res; 1259 int err; 1260 1261 /* alloc channel */ 1262 chan = kzalloc(sizeof(*chan), GFP_KERNEL); 1263 if (!chan) { 1264 dev_err(fdev->dev, "no free memory for DMA channels!\n"); 1265 err = -ENOMEM; 1266 goto out_return; 1267 } 1268 1269 /* ioremap registers for use */ 1270 chan->regs = of_iomap(node, 0); 1271 if (!chan->regs) { 1272 dev_err(fdev->dev, "unable to ioremap registers\n"); 1273 err = -ENOMEM; 1274 goto out_free_chan; 1275 } 1276 1277 err = of_address_to_resource(node, 0, &res); 1278 if (err) { 1279 dev_err(fdev->dev, "unable to find 'reg' property\n"); 1280 goto out_iounmap_regs; 1281 } 1282 1283 chan->feature = feature; 1284 if (!fdev->feature) 1285 fdev->feature = chan->feature; 1286 1287 /* 1288 * If the DMA device's feature is different than the feature 1289 * of its channels, report the bug 1290 */ 1291 WARN_ON(fdev->feature != chan->feature); 1292 1293 chan->dev = fdev->dev; 1294 chan->id = (res.start & 0xfff) < 0x300 ? 1295 ((res.start - 0x100) & 0xfff) >> 7 : 1296 ((res.start - 0x200) & 0xfff) >> 7; 1297 if (chan->id >= FSL_DMA_MAX_CHANS_PER_DEVICE) { 1298 dev_err(fdev->dev, "too many channels for device\n"); 1299 err = -EINVAL; 1300 goto out_iounmap_regs; 1301 } 1302 1303 fdev->chan[chan->id] = chan; 1304 tasklet_init(&chan->tasklet, dma_do_tasklet, (unsigned long)chan); 1305 snprintf(chan->name, sizeof(chan->name), "chan%d", chan->id); 1306 1307 /* Initialize the channel */ 1308 dma_init(chan); 1309 1310 /* Clear cdar registers */ 1311 set_cdar(chan, 0); 1312 1313 switch (chan->feature & FSL_DMA_IP_MASK) { 1314 case FSL_DMA_IP_85XX: 1315 chan->toggle_ext_pause = fsl_chan_toggle_ext_pause; 1316 case FSL_DMA_IP_83XX: 1317 chan->toggle_ext_start = fsl_chan_toggle_ext_start; 1318 chan->set_src_loop_size = fsl_chan_set_src_loop_size; 1319 chan->set_dst_loop_size = fsl_chan_set_dst_loop_size; 1320 chan->set_request_count = fsl_chan_set_request_count; 1321 } 1322 1323 spin_lock_init(&chan->desc_lock); 1324 INIT_LIST_HEAD(&chan->ld_pending); 1325 INIT_LIST_HEAD(&chan->ld_running); 1326 INIT_LIST_HEAD(&chan->ld_completed); 1327 chan->idle = true; 1328 #ifdef CONFIG_PM 1329 chan->pm_state = RUNNING; 1330 #endif 1331 1332 chan->common.device = &fdev->common; 1333 dma_cookie_init(&chan->common); 1334 1335 /* find the IRQ line, if it exists in the device tree */ 1336 chan->irq = irq_of_parse_and_map(node, 0); 1337 1338 /* Add the channel to DMA device channel list */ 1339 list_add_tail(&chan->common.device_node, &fdev->common.channels); 1340 fdev->common.chancnt++; 1341 1342 dev_info(fdev->dev, "#%d (%s), irq %d\n", chan->id, compatible, 1343 chan->irq != NO_IRQ ? chan->irq : fdev->irq); 1344 1345 return 0; 1346 1347 out_iounmap_regs: 1348 iounmap(chan->regs); 1349 out_free_chan: 1350 kfree(chan); 1351 out_return: 1352 return err; 1353 } 1354 1355 static void fsl_dma_chan_remove(struct fsldma_chan *chan) 1356 { 1357 irq_dispose_mapping(chan->irq); 1358 list_del(&chan->common.device_node); 1359 iounmap(chan->regs); 1360 kfree(chan); 1361 } 1362 1363 static int fsldma_of_probe(struct platform_device *op) 1364 { 1365 struct fsldma_device *fdev; 1366 struct device_node *child; 1367 int err; 1368 1369 fdev = kzalloc(sizeof(*fdev), GFP_KERNEL); 1370 if (!fdev) { 1371 dev_err(&op->dev, "No enough memory for 'priv'\n"); 1372 err = -ENOMEM; 1373 goto out_return; 1374 } 1375 1376 fdev->dev = &op->dev; 1377 INIT_LIST_HEAD(&fdev->common.channels); 1378 1379 /* ioremap the registers for use */ 1380 fdev->regs = of_iomap(op->dev.of_node, 0); 1381 if (!fdev->regs) { 1382 dev_err(&op->dev, "unable to ioremap registers\n"); 1383 err = -ENOMEM; 1384 goto out_free_fdev; 1385 } 1386 1387 /* map the channel IRQ if it exists, but don't hookup the handler yet */ 1388 fdev->irq = irq_of_parse_and_map(op->dev.of_node, 0); 1389 1390 dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask); 1391 dma_cap_set(DMA_SG, fdev->common.cap_mask); 1392 dma_cap_set(DMA_SLAVE, fdev->common.cap_mask); 1393 fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources; 1394 fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources; 1395 fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy; 1396 fdev->common.device_prep_dma_sg = fsl_dma_prep_sg; 1397 fdev->common.device_tx_status = fsl_tx_status; 1398 fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending; 1399 fdev->common.device_prep_slave_sg = fsl_dma_prep_slave_sg; 1400 fdev->common.device_control = fsl_dma_device_control; 1401 fdev->common.dev = &op->dev; 1402 1403 dma_set_mask(&(op->dev), DMA_BIT_MASK(36)); 1404 1405 platform_set_drvdata(op, fdev); 1406 1407 /* 1408 * We cannot use of_platform_bus_probe() because there is no 1409 * of_platform_bus_remove(). Instead, we manually instantiate every DMA 1410 * channel object. 1411 */ 1412 for_each_child_of_node(op->dev.of_node, child) { 1413 if (of_device_is_compatible(child, "fsl,eloplus-dma-channel")) { 1414 fsl_dma_chan_probe(fdev, child, 1415 FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN, 1416 "fsl,eloplus-dma-channel"); 1417 } 1418 1419 if (of_device_is_compatible(child, "fsl,elo-dma-channel")) { 1420 fsl_dma_chan_probe(fdev, child, 1421 FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN, 1422 "fsl,elo-dma-channel"); 1423 } 1424 } 1425 1426 /* 1427 * Hookup the IRQ handler(s) 1428 * 1429 * If we have a per-controller interrupt, we prefer that to the 1430 * per-channel interrupts to reduce the number of shared interrupt 1431 * handlers on the same IRQ line 1432 */ 1433 err = fsldma_request_irqs(fdev); 1434 if (err) { 1435 dev_err(fdev->dev, "unable to request IRQs\n"); 1436 goto out_free_fdev; 1437 } 1438 1439 dma_async_device_register(&fdev->common); 1440 return 0; 1441 1442 out_free_fdev: 1443 irq_dispose_mapping(fdev->irq); 1444 kfree(fdev); 1445 out_return: 1446 return err; 1447 } 1448 1449 static int fsldma_of_remove(struct platform_device *op) 1450 { 1451 struct fsldma_device *fdev; 1452 unsigned int i; 1453 1454 fdev = platform_get_drvdata(op); 1455 dma_async_device_unregister(&fdev->common); 1456 1457 fsldma_free_irqs(fdev); 1458 1459 for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { 1460 if (fdev->chan[i]) 1461 fsl_dma_chan_remove(fdev->chan[i]); 1462 } 1463 1464 iounmap(fdev->regs); 1465 kfree(fdev); 1466 1467 return 0; 1468 } 1469 1470 #ifdef CONFIG_PM 1471 static int fsldma_suspend_late(struct device *dev) 1472 { 1473 struct platform_device *pdev = to_platform_device(dev); 1474 struct fsldma_device *fdev = platform_get_drvdata(pdev); 1475 struct fsldma_chan *chan; 1476 int i; 1477 1478 for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { 1479 chan = fdev->chan[i]; 1480 if (!chan) 1481 continue; 1482 1483 spin_lock_bh(&chan->desc_lock); 1484 if (unlikely(!chan->idle)) 1485 goto out; 1486 chan->regs_save.mr = get_mr(chan); 1487 chan->pm_state = SUSPENDED; 1488 spin_unlock_bh(&chan->desc_lock); 1489 } 1490 return 0; 1491 1492 out: 1493 for (; i >= 0; i--) { 1494 chan = fdev->chan[i]; 1495 if (!chan) 1496 continue; 1497 chan->pm_state = RUNNING; 1498 spin_unlock_bh(&chan->desc_lock); 1499 } 1500 return -EBUSY; 1501 } 1502 1503 static int fsldma_resume_early(struct device *dev) 1504 { 1505 struct platform_device *pdev = to_platform_device(dev); 1506 struct fsldma_device *fdev = platform_get_drvdata(pdev); 1507 struct fsldma_chan *chan; 1508 u32 mode; 1509 int i; 1510 1511 for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { 1512 chan = fdev->chan[i]; 1513 if (!chan) 1514 continue; 1515 1516 spin_lock_bh(&chan->desc_lock); 1517 mode = chan->regs_save.mr 1518 & ~FSL_DMA_MR_CS & ~FSL_DMA_MR_CC & ~FSL_DMA_MR_CA; 1519 set_mr(chan, mode); 1520 chan->pm_state = RUNNING; 1521 spin_unlock_bh(&chan->desc_lock); 1522 } 1523 1524 return 0; 1525 } 1526 1527 static const struct dev_pm_ops fsldma_pm_ops = { 1528 .suspend_late = fsldma_suspend_late, 1529 .resume_early = fsldma_resume_early, 1530 }; 1531 #endif 1532 1533 static const struct of_device_id fsldma_of_ids[] = { 1534 { .compatible = "fsl,elo3-dma", }, 1535 { .compatible = "fsl,eloplus-dma", }, 1536 { .compatible = "fsl,elo-dma", }, 1537 {} 1538 }; 1539 1540 static struct platform_driver fsldma_of_driver = { 1541 .driver = { 1542 .name = "fsl-elo-dma", 1543 .owner = THIS_MODULE, 1544 .of_match_table = fsldma_of_ids, 1545 #ifdef CONFIG_PM 1546 .pm = &fsldma_pm_ops, 1547 #endif 1548 }, 1549 .probe = fsldma_of_probe, 1550 .remove = fsldma_of_remove, 1551 }; 1552 1553 /*----------------------------------------------------------------------------*/ 1554 /* Module Init / Exit */ 1555 /*----------------------------------------------------------------------------*/ 1556 1557 static __init int fsldma_init(void) 1558 { 1559 pr_info("Freescale Elo series DMA driver\n"); 1560 return platform_driver_register(&fsldma_of_driver); 1561 } 1562 1563 static void __exit fsldma_exit(void) 1564 { 1565 platform_driver_unregister(&fsldma_of_driver); 1566 } 1567 1568 subsys_initcall(fsldma_init); 1569 module_exit(fsldma_exit); 1570 1571 MODULE_DESCRIPTION("Freescale Elo series DMA driver"); 1572 MODULE_LICENSE("GPL"); 1573