1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * bcm2835 sdhost driver. 4 * 5 * The 2835 has two SD controllers: The Arasan sdhci controller 6 * (supported by the iproc driver) and a custom sdhost controller 7 * (supported by this driver). 8 * 9 * The sdhci controller supports both sdcard and sdio. The sdhost 10 * controller supports the sdcard only, but has better performance. 11 * Also note that the rpi3 has sdio wifi, so driving the sdcard with 12 * the sdhost controller allows to use the sdhci controller for wifi 13 * support. 14 * 15 * The configuration is done by devicetree via pin muxing. Both 16 * SD controller are available on the same pins (2 pin groups = pin 22 17 * to 27 + pin 48 to 53). So it's possible to use both SD controllers 18 * at the same time with different pin groups. 19 * 20 * Author: Phil Elwell <phil@raspberrypi.org> 21 * Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd. 22 * 23 * Based on 24 * mmc-bcm2835.c by Gellert Weisz 25 * which is, in turn, based on 26 * sdhci-bcm2708.c by Broadcom 27 * sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko 28 * sdhci.c and sdhci-pci.c by Pierre Ossman 29 */ 30 #include <linux/clk.h> 31 #include <linux/delay.h> 32 #include <linux/device.h> 33 #include <linux/dmaengine.h> 34 #include <linux/dma-mapping.h> 35 #include <linux/err.h> 36 #include <linux/highmem.h> 37 #include <linux/interrupt.h> 38 #include <linux/io.h> 39 #include <linux/iopoll.h> 40 #include <linux/module.h> 41 #include <linux/of_address.h> 42 #include <linux/of_irq.h> 43 #include <linux/platform_device.h> 44 #include <linux/scatterlist.h> 45 #include <linux/time.h> 46 #include <linux/workqueue.h> 47 48 #include <linux/mmc/host.h> 49 #include <linux/mmc/mmc.h> 50 #include <linux/mmc/sd.h> 51 52 #define SDCMD 0x00 /* Command to SD card - 16 R/W */ 53 #define SDARG 0x04 /* Argument to SD card - 32 R/W */ 54 #define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */ 55 #define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */ 56 #define SDRSP0 0x10 /* SD card response (31:0) - 32 R */ 57 #define SDRSP1 0x14 /* SD card response (63:32) - 32 R */ 58 #define SDRSP2 0x18 /* SD card response (95:64) - 32 R */ 59 #define SDRSP3 0x1c /* SD card response (127:96) - 32 R */ 60 #define SDHSTS 0x20 /* SD host status - 11 R/W */ 61 #define SDVDD 0x30 /* SD card power control - 1 R/W */ 62 #define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */ 63 #define SDHCFG 0x38 /* Host configuration - 2 R/W */ 64 #define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */ 65 #define SDDATA 0x40 /* Data to/from SD card - 32 R/W */ 66 #define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */ 67 68 #define SDCMD_NEW_FLAG 0x8000 69 #define SDCMD_FAIL_FLAG 0x4000 70 #define SDCMD_BUSYWAIT 0x800 71 #define SDCMD_NO_RESPONSE 0x400 72 #define SDCMD_LONG_RESPONSE 0x200 73 #define SDCMD_WRITE_CMD 0x80 74 #define SDCMD_READ_CMD 0x40 75 #define SDCMD_CMD_MASK 0x3f 76 77 #define SDCDIV_MAX_CDIV 0x7ff 78 79 #define SDHSTS_BUSY_IRPT 0x400 80 #define SDHSTS_BLOCK_IRPT 0x200 81 #define SDHSTS_SDIO_IRPT 0x100 82 #define SDHSTS_REW_TIME_OUT 0x80 83 #define SDHSTS_CMD_TIME_OUT 0x40 84 #define SDHSTS_CRC16_ERROR 0x20 85 #define SDHSTS_CRC7_ERROR 0x10 86 #define SDHSTS_FIFO_ERROR 0x08 87 /* Reserved */ 88 /* Reserved */ 89 #define SDHSTS_DATA_FLAG 0x01 90 91 #define SDHSTS_TRANSFER_ERROR_MASK (SDHSTS_CRC7_ERROR | \ 92 SDHSTS_CRC16_ERROR | \ 93 SDHSTS_REW_TIME_OUT | \ 94 SDHSTS_FIFO_ERROR) 95 96 #define SDHSTS_ERROR_MASK (SDHSTS_CMD_TIME_OUT | \ 97 SDHSTS_TRANSFER_ERROR_MASK) 98 99 #define SDHCFG_BUSY_IRPT_EN BIT(10) 100 #define SDHCFG_BLOCK_IRPT_EN BIT(8) 101 #define SDHCFG_SDIO_IRPT_EN BIT(5) 102 #define SDHCFG_DATA_IRPT_EN BIT(4) 103 #define SDHCFG_SLOW_CARD BIT(3) 104 #define SDHCFG_WIDE_EXT_BUS BIT(2) 105 #define SDHCFG_WIDE_INT_BUS BIT(1) 106 #define SDHCFG_REL_CMD_LINE BIT(0) 107 108 #define SDVDD_POWER_OFF 0 109 #define SDVDD_POWER_ON 1 110 111 #define SDEDM_FORCE_DATA_MODE BIT(19) 112 #define SDEDM_CLOCK_PULSE BIT(20) 113 #define SDEDM_BYPASS BIT(21) 114 115 #define SDEDM_WRITE_THRESHOLD_SHIFT 9 116 #define SDEDM_READ_THRESHOLD_SHIFT 14 117 #define SDEDM_THRESHOLD_MASK 0x1f 118 119 #define SDEDM_FSM_MASK 0xf 120 #define SDEDM_FSM_IDENTMODE 0x0 121 #define SDEDM_FSM_DATAMODE 0x1 122 #define SDEDM_FSM_READDATA 0x2 123 #define SDEDM_FSM_WRITEDATA 0x3 124 #define SDEDM_FSM_READWAIT 0x4 125 #define SDEDM_FSM_READCRC 0x5 126 #define SDEDM_FSM_WRITECRC 0x6 127 #define SDEDM_FSM_WRITEWAIT1 0x7 128 #define SDEDM_FSM_POWERDOWN 0x8 129 #define SDEDM_FSM_POWERUP 0x9 130 #define SDEDM_FSM_WRITESTART1 0xa 131 #define SDEDM_FSM_WRITESTART2 0xb 132 #define SDEDM_FSM_GENPULSES 0xc 133 #define SDEDM_FSM_WRITEWAIT2 0xd 134 #define SDEDM_FSM_STARTPOWDOWN 0xf 135 136 #define SDDATA_FIFO_WORDS 16 137 138 #define FIFO_READ_THRESHOLD 4 139 #define FIFO_WRITE_THRESHOLD 4 140 #define SDDATA_FIFO_PIO_BURST 8 141 142 #define PIO_THRESHOLD 1 /* Maximum block count for PIO (0 = always DMA) */ 143 144 struct bcm2835_host { 145 spinlock_t lock; 146 struct mutex mutex; 147 148 void __iomem *ioaddr; 149 u32 phys_addr; 150 151 struct platform_device *pdev; 152 153 int clock; /* Current clock speed */ 154 unsigned int max_clk; /* Max possible freq */ 155 struct work_struct dma_work; 156 struct delayed_work timeout_work; /* Timer for timeouts */ 157 struct sg_mapping_iter sg_miter; /* SG state for PIO */ 158 unsigned int blocks; /* remaining PIO blocks */ 159 int irq; /* Device IRQ */ 160 161 u32 ns_per_fifo_word; 162 163 /* cached registers */ 164 u32 hcfg; 165 u32 cdiv; 166 167 struct mmc_request *mrq; /* Current request */ 168 struct mmc_command *cmd; /* Current command */ 169 struct mmc_data *data; /* Current data request */ 170 bool data_complete:1;/* Data finished before cmd */ 171 bool use_busy:1; /* Wait for busy interrupt */ 172 bool use_sbc:1; /* Send CMD23 */ 173 174 /* for threaded irq handler */ 175 bool irq_block; 176 bool irq_busy; 177 bool irq_data; 178 179 /* DMA part */ 180 struct dma_chan *dma_chan_rxtx; 181 struct dma_chan *dma_chan; 182 struct dma_slave_config dma_cfg_rx; 183 struct dma_slave_config dma_cfg_tx; 184 struct dma_async_tx_descriptor *dma_desc; 185 u32 dma_dir; 186 u32 drain_words; 187 struct page *drain_page; 188 u32 drain_offset; 189 bool use_dma; 190 }; 191 192 static void bcm2835_dumpcmd(struct bcm2835_host *host, struct mmc_command *cmd, 193 const char *label) 194 { 195 struct device *dev = &host->pdev->dev; 196 197 if (!cmd) 198 return; 199 200 dev_dbg(dev, "%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n", 201 (cmd == host->cmd) ? '>' : ' ', 202 label, cmd->opcode, cmd->arg, cmd->flags, 203 cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3], 204 cmd->error); 205 } 206 207 static void bcm2835_dumpregs(struct bcm2835_host *host) 208 { 209 struct mmc_request *mrq = host->mrq; 210 struct device *dev = &host->pdev->dev; 211 212 if (mrq) { 213 bcm2835_dumpcmd(host, mrq->sbc, "sbc"); 214 bcm2835_dumpcmd(host, mrq->cmd, "cmd"); 215 if (mrq->data) { 216 dev_dbg(dev, "data blocks %x blksz %x - err %d\n", 217 mrq->data->blocks, 218 mrq->data->blksz, 219 mrq->data->error); 220 } 221 bcm2835_dumpcmd(host, mrq->stop, "stop"); 222 } 223 224 dev_dbg(dev, "=========== REGISTER DUMP ===========\n"); 225 dev_dbg(dev, "SDCMD 0x%08x\n", readl(host->ioaddr + SDCMD)); 226 dev_dbg(dev, "SDARG 0x%08x\n", readl(host->ioaddr + SDARG)); 227 dev_dbg(dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT)); 228 dev_dbg(dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV)); 229 dev_dbg(dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0)); 230 dev_dbg(dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1)); 231 dev_dbg(dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2)); 232 dev_dbg(dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3)); 233 dev_dbg(dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS)); 234 dev_dbg(dev, "SDVDD 0x%08x\n", readl(host->ioaddr + SDVDD)); 235 dev_dbg(dev, "SDEDM 0x%08x\n", readl(host->ioaddr + SDEDM)); 236 dev_dbg(dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG)); 237 dev_dbg(dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT)); 238 dev_dbg(dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC)); 239 dev_dbg(dev, "===========================================\n"); 240 } 241 242 static void bcm2835_reset_internal(struct bcm2835_host *host) 243 { 244 u32 temp; 245 246 writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD); 247 writel(0, host->ioaddr + SDCMD); 248 writel(0, host->ioaddr + SDARG); 249 writel(0xf00000, host->ioaddr + SDTOUT); 250 writel(0, host->ioaddr + SDCDIV); 251 writel(0x7f8, host->ioaddr + SDHSTS); /* Write 1s to clear */ 252 writel(0, host->ioaddr + SDHCFG); 253 writel(0, host->ioaddr + SDHBCT); 254 writel(0, host->ioaddr + SDHBLC); 255 256 /* Limit fifo usage due to silicon bug */ 257 temp = readl(host->ioaddr + SDEDM); 258 temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) | 259 (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT)); 260 temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) | 261 (FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT); 262 writel(temp, host->ioaddr + SDEDM); 263 msleep(20); 264 writel(SDVDD_POWER_ON, host->ioaddr + SDVDD); 265 msleep(20); 266 host->clock = 0; 267 writel(host->hcfg, host->ioaddr + SDHCFG); 268 writel(host->cdiv, host->ioaddr + SDCDIV); 269 } 270 271 static void bcm2835_reset(struct mmc_host *mmc) 272 { 273 struct bcm2835_host *host = mmc_priv(mmc); 274 275 if (host->dma_chan) 276 dmaengine_terminate_sync(host->dma_chan); 277 host->dma_chan = NULL; 278 bcm2835_reset_internal(host); 279 } 280 281 static void bcm2835_finish_command(struct bcm2835_host *host); 282 283 static void bcm2835_wait_transfer_complete(struct bcm2835_host *host) 284 { 285 int timediff; 286 u32 alternate_idle; 287 288 alternate_idle = (host->mrq->data->flags & MMC_DATA_READ) ? 289 SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1; 290 291 timediff = 0; 292 293 while (1) { 294 u32 edm, fsm; 295 296 edm = readl(host->ioaddr + SDEDM); 297 fsm = edm & SDEDM_FSM_MASK; 298 299 if ((fsm == SDEDM_FSM_IDENTMODE) || 300 (fsm == SDEDM_FSM_DATAMODE)) 301 break; 302 if (fsm == alternate_idle) { 303 writel(edm | SDEDM_FORCE_DATA_MODE, 304 host->ioaddr + SDEDM); 305 break; 306 } 307 308 timediff++; 309 if (timediff == 100000) { 310 dev_err(&host->pdev->dev, 311 "wait_transfer_complete - still waiting after %d retries\n", 312 timediff); 313 bcm2835_dumpregs(host); 314 host->mrq->data->error = -ETIMEDOUT; 315 return; 316 } 317 cpu_relax(); 318 } 319 } 320 321 static void bcm2835_dma_complete(void *param) 322 { 323 struct bcm2835_host *host = param; 324 325 schedule_work(&host->dma_work); 326 } 327 328 static void bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read) 329 { 330 size_t blksize; 331 unsigned long wait_max; 332 333 blksize = host->data->blksz; 334 335 wait_max = jiffies + msecs_to_jiffies(500); 336 337 while (blksize) { 338 int copy_words; 339 u32 hsts = 0; 340 size_t len; 341 u32 *buf; 342 343 if (!sg_miter_next(&host->sg_miter)) { 344 host->data->error = -EINVAL; 345 break; 346 } 347 348 len = min(host->sg_miter.length, blksize); 349 if (len % 4) { 350 host->data->error = -EINVAL; 351 break; 352 } 353 354 blksize -= len; 355 host->sg_miter.consumed = len; 356 357 buf = (u32 *)host->sg_miter.addr; 358 359 copy_words = len / 4; 360 361 while (copy_words) { 362 int burst_words, words; 363 u32 edm; 364 365 burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words); 366 edm = readl(host->ioaddr + SDEDM); 367 if (is_read) 368 words = ((edm >> 4) & 0x1f); 369 else 370 words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f); 371 372 if (words < burst_words) { 373 int fsm_state = (edm & SDEDM_FSM_MASK); 374 struct device *dev = &host->pdev->dev; 375 376 if ((is_read && 377 (fsm_state != SDEDM_FSM_READDATA && 378 fsm_state != SDEDM_FSM_READWAIT && 379 fsm_state != SDEDM_FSM_READCRC)) || 380 (!is_read && 381 (fsm_state != SDEDM_FSM_WRITEDATA && 382 fsm_state != SDEDM_FSM_WRITESTART1 && 383 fsm_state != SDEDM_FSM_WRITESTART2))) { 384 hsts = readl(host->ioaddr + SDHSTS); 385 dev_err(dev, "fsm %x, hsts %08x\n", 386 fsm_state, hsts); 387 if (hsts & SDHSTS_ERROR_MASK) 388 break; 389 } 390 391 if (time_after(jiffies, wait_max)) { 392 dev_err(dev, "PIO %s timeout - EDM %08x\n", 393 is_read ? "read" : "write", 394 edm); 395 hsts = SDHSTS_REW_TIME_OUT; 396 break; 397 } 398 ndelay((burst_words - words) * 399 host->ns_per_fifo_word); 400 continue; 401 } else if (words > copy_words) { 402 words = copy_words; 403 } 404 405 copy_words -= words; 406 407 while (words) { 408 if (is_read) 409 *(buf++) = readl(host->ioaddr + SDDATA); 410 else 411 writel(*(buf++), host->ioaddr + SDDATA); 412 words--; 413 } 414 } 415 416 if (hsts & SDHSTS_ERROR_MASK) 417 break; 418 } 419 420 sg_miter_stop(&host->sg_miter); 421 } 422 423 static void bcm2835_transfer_pio(struct bcm2835_host *host) 424 { 425 struct device *dev = &host->pdev->dev; 426 u32 sdhsts; 427 bool is_read; 428 429 is_read = (host->data->flags & MMC_DATA_READ) != 0; 430 bcm2835_transfer_block_pio(host, is_read); 431 432 sdhsts = readl(host->ioaddr + SDHSTS); 433 if (sdhsts & (SDHSTS_CRC16_ERROR | 434 SDHSTS_CRC7_ERROR | 435 SDHSTS_FIFO_ERROR)) { 436 dev_err(dev, "%s transfer error - HSTS %08x\n", 437 is_read ? "read" : "write", sdhsts); 438 host->data->error = -EILSEQ; 439 } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT | 440 SDHSTS_REW_TIME_OUT))) { 441 dev_err(dev, "%s timeout error - HSTS %08x\n", 442 is_read ? "read" : "write", sdhsts); 443 host->data->error = -ETIMEDOUT; 444 } 445 } 446 447 static 448 void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data) 449 { 450 int sg_len, dir_data, dir_slave; 451 struct dma_async_tx_descriptor *desc = NULL; 452 struct dma_chan *dma_chan; 453 454 dma_chan = host->dma_chan_rxtx; 455 if (data->flags & MMC_DATA_READ) { 456 dir_data = DMA_FROM_DEVICE; 457 dir_slave = DMA_DEV_TO_MEM; 458 } else { 459 dir_data = DMA_TO_DEVICE; 460 dir_slave = DMA_MEM_TO_DEV; 461 } 462 463 /* The block doesn't manage the FIFO DREQs properly for 464 * multi-block transfers, so don't attempt to DMA the final 465 * few words. Unfortunately this requires the final sg entry 466 * to be trimmed. N.B. This code demands that the overspill 467 * is contained in a single sg entry. 468 */ 469 470 host->drain_words = 0; 471 if ((data->blocks > 1) && (dir_data == DMA_FROM_DEVICE)) { 472 struct scatterlist *sg; 473 u32 len; 474 int i; 475 476 len = min((u32)(FIFO_READ_THRESHOLD - 1) * 4, 477 (u32)data->blocks * data->blksz); 478 479 for_each_sg(data->sg, sg, data->sg_len, i) { 480 if (sg_is_last(sg)) { 481 WARN_ON(sg->length < len); 482 sg->length -= len; 483 host->drain_page = sg_page(sg); 484 host->drain_offset = sg->offset + sg->length; 485 } 486 } 487 host->drain_words = len / 4; 488 } 489 490 /* The parameters have already been validated, so this will not fail */ 491 (void)dmaengine_slave_config(dma_chan, 492 (dir_data == DMA_FROM_DEVICE) ? 493 &host->dma_cfg_rx : 494 &host->dma_cfg_tx); 495 496 sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len, 497 dir_data); 498 if (!sg_len) 499 return; 500 501 desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave, 502 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 503 504 if (!desc) { 505 dma_unmap_sg(dma_chan->device->dev, data->sg, sg_len, dir_data); 506 return; 507 } 508 509 desc->callback = bcm2835_dma_complete; 510 desc->callback_param = host; 511 host->dma_desc = desc; 512 host->dma_chan = dma_chan; 513 host->dma_dir = dir_data; 514 } 515 516 static void bcm2835_start_dma(struct bcm2835_host *host) 517 { 518 dmaengine_submit(host->dma_desc); 519 dma_async_issue_pending(host->dma_chan); 520 } 521 522 static void bcm2835_set_transfer_irqs(struct bcm2835_host *host) 523 { 524 u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN | 525 SDHCFG_BUSY_IRPT_EN; 526 527 if (host->dma_desc) { 528 host->hcfg = (host->hcfg & ~all_irqs) | 529 SDHCFG_BUSY_IRPT_EN; 530 } else { 531 host->hcfg = (host->hcfg & ~all_irqs) | 532 SDHCFG_DATA_IRPT_EN | 533 SDHCFG_BUSY_IRPT_EN; 534 } 535 536 writel(host->hcfg, host->ioaddr + SDHCFG); 537 } 538 539 static 540 void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_command *cmd) 541 { 542 struct mmc_data *data = cmd->data; 543 544 WARN_ON(host->data); 545 546 host->data = data; 547 if (!data) 548 return; 549 550 host->data_complete = false; 551 host->data->bytes_xfered = 0; 552 553 if (!host->dma_desc) { 554 /* Use PIO */ 555 int flags = SG_MITER_ATOMIC; 556 557 if (data->flags & MMC_DATA_READ) 558 flags |= SG_MITER_TO_SG; 559 else 560 flags |= SG_MITER_FROM_SG; 561 sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags); 562 host->blocks = data->blocks; 563 } 564 565 bcm2835_set_transfer_irqs(host); 566 567 writel(data->blksz, host->ioaddr + SDHBCT); 568 writel(data->blocks, host->ioaddr + SDHBLC); 569 } 570 571 static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host, u32 max_ms) 572 { 573 struct device *dev = &host->pdev->dev; 574 u32 value; 575 int ret; 576 577 ret = readl_poll_timeout(host->ioaddr + SDCMD, value, 578 !(value & SDCMD_NEW_FLAG), 1, 10); 579 if (ret == -ETIMEDOUT) 580 /* if it takes a while make poll interval bigger */ 581 ret = readl_poll_timeout(host->ioaddr + SDCMD, value, 582 !(value & SDCMD_NEW_FLAG), 583 10, max_ms * 1000); 584 if (ret == -ETIMEDOUT) 585 dev_err(dev, "%s: timeout (%d ms)\n", __func__, max_ms); 586 587 return value; 588 } 589 590 static void bcm2835_finish_request(struct bcm2835_host *host) 591 { 592 struct dma_chan *terminate_chan = NULL; 593 struct mmc_request *mrq; 594 595 cancel_delayed_work(&host->timeout_work); 596 597 mrq = host->mrq; 598 599 host->mrq = NULL; 600 host->cmd = NULL; 601 host->data = NULL; 602 603 host->dma_desc = NULL; 604 terminate_chan = host->dma_chan; 605 host->dma_chan = NULL; 606 607 if (terminate_chan) { 608 int err = dmaengine_terminate_all(terminate_chan); 609 610 if (err) 611 dev_err(&host->pdev->dev, 612 "failed to terminate DMA (%d)\n", err); 613 } 614 615 mmc_request_done(mmc_from_priv(host), mrq); 616 } 617 618 static 619 bool bcm2835_send_command(struct bcm2835_host *host, struct mmc_command *cmd) 620 { 621 struct device *dev = &host->pdev->dev; 622 u32 sdcmd, sdhsts; 623 unsigned long timeout; 624 625 WARN_ON(host->cmd); 626 627 sdcmd = bcm2835_read_wait_sdcmd(host, 100); 628 if (sdcmd & SDCMD_NEW_FLAG) { 629 dev_err(dev, "previous command never completed.\n"); 630 bcm2835_dumpregs(host); 631 cmd->error = -EILSEQ; 632 bcm2835_finish_request(host); 633 return false; 634 } 635 636 if (!cmd->data && cmd->busy_timeout > 9000) 637 timeout = DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ; 638 else 639 timeout = 10 * HZ; 640 schedule_delayed_work(&host->timeout_work, timeout); 641 642 host->cmd = cmd; 643 644 /* Clear any error flags */ 645 sdhsts = readl(host->ioaddr + SDHSTS); 646 if (sdhsts & SDHSTS_ERROR_MASK) 647 writel(sdhsts, host->ioaddr + SDHSTS); 648 649 if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) { 650 dev_err(dev, "unsupported response type!\n"); 651 cmd->error = -EINVAL; 652 bcm2835_finish_request(host); 653 return false; 654 } 655 656 bcm2835_prepare_data(host, cmd); 657 658 writel(cmd->arg, host->ioaddr + SDARG); 659 660 sdcmd = cmd->opcode & SDCMD_CMD_MASK; 661 662 host->use_busy = false; 663 if (!(cmd->flags & MMC_RSP_PRESENT)) { 664 sdcmd |= SDCMD_NO_RESPONSE; 665 } else { 666 if (cmd->flags & MMC_RSP_136) 667 sdcmd |= SDCMD_LONG_RESPONSE; 668 if (cmd->flags & MMC_RSP_BUSY) { 669 sdcmd |= SDCMD_BUSYWAIT; 670 host->use_busy = true; 671 } 672 } 673 674 if (cmd->data) { 675 if (cmd->data->flags & MMC_DATA_WRITE) 676 sdcmd |= SDCMD_WRITE_CMD; 677 if (cmd->data->flags & MMC_DATA_READ) 678 sdcmd |= SDCMD_READ_CMD; 679 } 680 681 writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD); 682 683 return true; 684 } 685 686 static void bcm2835_transfer_complete(struct bcm2835_host *host) 687 { 688 struct mmc_data *data; 689 690 WARN_ON(!host->data_complete); 691 692 data = host->data; 693 host->data = NULL; 694 695 /* Need to send CMD12 if - 696 * a) open-ended multiblock transfer (no CMD23) 697 * b) error in multiblock transfer 698 */ 699 if (host->mrq->stop && (data->error || !host->use_sbc)) { 700 if (bcm2835_send_command(host, host->mrq->stop)) { 701 /* No busy, so poll for completion */ 702 if (!host->use_busy) 703 bcm2835_finish_command(host); 704 } 705 } else { 706 bcm2835_wait_transfer_complete(host); 707 bcm2835_finish_request(host); 708 } 709 } 710 711 static void bcm2835_finish_data(struct bcm2835_host *host) 712 { 713 struct device *dev = &host->pdev->dev; 714 struct mmc_data *data; 715 716 data = host->data; 717 718 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); 719 writel(host->hcfg, host->ioaddr + SDHCFG); 720 721 data->bytes_xfered = data->error ? 0 : (data->blksz * data->blocks); 722 723 host->data_complete = true; 724 725 if (host->cmd) { 726 /* Data managed to finish before the 727 * command completed. Make sure we do 728 * things in the proper order. 729 */ 730 dev_dbg(dev, "Finished early - HSTS %08x\n", 731 readl(host->ioaddr + SDHSTS)); 732 } else { 733 bcm2835_transfer_complete(host); 734 } 735 } 736 737 static void bcm2835_finish_command(struct bcm2835_host *host) 738 { 739 struct device *dev = &host->pdev->dev; 740 struct mmc_command *cmd = host->cmd; 741 u32 sdcmd; 742 743 sdcmd = bcm2835_read_wait_sdcmd(host, 100); 744 745 /* Check for errors */ 746 if (sdcmd & SDCMD_NEW_FLAG) { 747 dev_err(dev, "command never completed.\n"); 748 bcm2835_dumpregs(host); 749 host->cmd->error = -EIO; 750 bcm2835_finish_request(host); 751 return; 752 } else if (sdcmd & SDCMD_FAIL_FLAG) { 753 u32 sdhsts = readl(host->ioaddr + SDHSTS); 754 755 /* Clear the errors */ 756 writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS); 757 758 if (!(sdhsts & SDHSTS_CRC7_ERROR) || 759 (host->cmd->opcode != MMC_SEND_OP_COND)) { 760 u32 edm, fsm; 761 762 if (sdhsts & SDHSTS_CMD_TIME_OUT) { 763 host->cmd->error = -ETIMEDOUT; 764 } else { 765 dev_err(dev, "unexpected command %d error\n", 766 host->cmd->opcode); 767 bcm2835_dumpregs(host); 768 host->cmd->error = -EILSEQ; 769 } 770 edm = readl(host->ioaddr + SDEDM); 771 fsm = edm & SDEDM_FSM_MASK; 772 if (fsm == SDEDM_FSM_READWAIT || 773 fsm == SDEDM_FSM_WRITESTART1) 774 /* Kick the FSM out of its wait */ 775 writel(edm | SDEDM_FORCE_DATA_MODE, 776 host->ioaddr + SDEDM); 777 bcm2835_finish_request(host); 778 return; 779 } 780 } 781 782 if (cmd->flags & MMC_RSP_PRESENT) { 783 if (cmd->flags & MMC_RSP_136) { 784 int i; 785 786 for (i = 0; i < 4; i++) { 787 cmd->resp[3 - i] = 788 readl(host->ioaddr + SDRSP0 + i * 4); 789 } 790 } else { 791 cmd->resp[0] = readl(host->ioaddr + SDRSP0); 792 } 793 } 794 795 if (cmd == host->mrq->sbc) { 796 /* Finished CMD23, now send actual command. */ 797 host->cmd = NULL; 798 if (bcm2835_send_command(host, host->mrq->cmd)) { 799 if (host->data && host->dma_desc) 800 /* DMA transfer starts now, PIO starts 801 * after irq 802 */ 803 bcm2835_start_dma(host); 804 805 if (!host->use_busy) 806 bcm2835_finish_command(host); 807 } 808 } else if (cmd == host->mrq->stop) { 809 /* Finished CMD12 */ 810 bcm2835_finish_request(host); 811 } else { 812 /* Processed actual command. */ 813 host->cmd = NULL; 814 if (!host->data) 815 bcm2835_finish_request(host); 816 else if (host->data_complete) 817 bcm2835_transfer_complete(host); 818 } 819 } 820 821 static void bcm2835_timeout(struct work_struct *work) 822 { 823 struct delayed_work *d = to_delayed_work(work); 824 struct bcm2835_host *host = 825 container_of(d, struct bcm2835_host, timeout_work); 826 struct device *dev = &host->pdev->dev; 827 828 mutex_lock(&host->mutex); 829 830 if (host->mrq) { 831 dev_err(dev, "timeout waiting for hardware interrupt.\n"); 832 bcm2835_dumpregs(host); 833 834 bcm2835_reset(mmc_from_priv(host)); 835 836 if (host->data) { 837 host->data->error = -ETIMEDOUT; 838 bcm2835_finish_data(host); 839 } else { 840 if (host->cmd) 841 host->cmd->error = -ETIMEDOUT; 842 else 843 host->mrq->cmd->error = -ETIMEDOUT; 844 845 bcm2835_finish_request(host); 846 } 847 } 848 849 mutex_unlock(&host->mutex); 850 } 851 852 static bool bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask) 853 { 854 struct device *dev = &host->pdev->dev; 855 856 if (!(intmask & SDHSTS_ERROR_MASK)) 857 return false; 858 859 if (!host->cmd) 860 return true; 861 862 dev_err(dev, "sdhost_busy_irq: intmask %08x\n", intmask); 863 if (intmask & SDHSTS_CRC7_ERROR) { 864 host->cmd->error = -EILSEQ; 865 } else if (intmask & (SDHSTS_CRC16_ERROR | 866 SDHSTS_FIFO_ERROR)) { 867 if (host->mrq->data) 868 host->mrq->data->error = -EILSEQ; 869 else 870 host->cmd->error = -EILSEQ; 871 } else if (intmask & SDHSTS_REW_TIME_OUT) { 872 if (host->mrq->data) 873 host->mrq->data->error = -ETIMEDOUT; 874 else 875 host->cmd->error = -ETIMEDOUT; 876 } else if (intmask & SDHSTS_CMD_TIME_OUT) { 877 host->cmd->error = -ETIMEDOUT; 878 } 879 bcm2835_dumpregs(host); 880 return true; 881 } 882 883 static void bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask) 884 { 885 if (!host->data) 886 return; 887 if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR)) 888 host->data->error = -EILSEQ; 889 if (intmask & SDHSTS_REW_TIME_OUT) 890 host->data->error = -ETIMEDOUT; 891 } 892 893 static void bcm2835_busy_irq(struct bcm2835_host *host) 894 { 895 if (WARN_ON(!host->cmd)) { 896 bcm2835_dumpregs(host); 897 return; 898 } 899 900 if (WARN_ON(!host->use_busy)) { 901 bcm2835_dumpregs(host); 902 return; 903 } 904 host->use_busy = false; 905 906 bcm2835_finish_command(host); 907 } 908 909 static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask) 910 { 911 /* There are no dedicated data/space available interrupt 912 * status bits, so it is necessary to use the single shared 913 * data/space available FIFO status bits. It is therefore not 914 * an error to get here when there is no data transfer in 915 * progress. 916 */ 917 if (!host->data) 918 return; 919 920 bcm2835_check_data_error(host, intmask); 921 if (host->data->error) 922 goto finished; 923 924 if (host->data->flags & MMC_DATA_WRITE) { 925 /* Use the block interrupt for writes after the first block */ 926 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN); 927 host->hcfg |= SDHCFG_BLOCK_IRPT_EN; 928 writel(host->hcfg, host->ioaddr + SDHCFG); 929 bcm2835_transfer_pio(host); 930 } else { 931 bcm2835_transfer_pio(host); 932 host->blocks--; 933 if ((host->blocks == 0) || host->data->error) 934 goto finished; 935 } 936 return; 937 938 finished: 939 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); 940 writel(host->hcfg, host->ioaddr + SDHCFG); 941 } 942 943 static void bcm2835_data_threaded_irq(struct bcm2835_host *host) 944 { 945 if (!host->data) 946 return; 947 if ((host->blocks == 0) || host->data->error) 948 bcm2835_finish_data(host); 949 } 950 951 static void bcm2835_block_irq(struct bcm2835_host *host) 952 { 953 if (WARN_ON(!host->data)) { 954 bcm2835_dumpregs(host); 955 return; 956 } 957 958 if (!host->dma_desc) { 959 WARN_ON(!host->blocks); 960 if (host->data->error || (--host->blocks == 0)) 961 bcm2835_finish_data(host); 962 else 963 bcm2835_transfer_pio(host); 964 } else if (host->data->flags & MMC_DATA_WRITE) { 965 bcm2835_finish_data(host); 966 } 967 } 968 969 static irqreturn_t bcm2835_irq(int irq, void *dev_id) 970 { 971 irqreturn_t result = IRQ_NONE; 972 struct bcm2835_host *host = dev_id; 973 u32 intmask; 974 975 spin_lock(&host->lock); 976 977 intmask = readl(host->ioaddr + SDHSTS); 978 979 writel(SDHSTS_BUSY_IRPT | 980 SDHSTS_BLOCK_IRPT | 981 SDHSTS_SDIO_IRPT | 982 SDHSTS_DATA_FLAG, 983 host->ioaddr + SDHSTS); 984 985 if (intmask & SDHSTS_BLOCK_IRPT) { 986 bcm2835_check_data_error(host, intmask); 987 host->irq_block = true; 988 result = IRQ_WAKE_THREAD; 989 } 990 991 if (intmask & SDHSTS_BUSY_IRPT) { 992 if (!bcm2835_check_cmd_error(host, intmask)) { 993 host->irq_busy = true; 994 result = IRQ_WAKE_THREAD; 995 } else { 996 result = IRQ_HANDLED; 997 } 998 } 999 1000 /* There is no true data interrupt status bit, so it is 1001 * necessary to qualify the data flag with the interrupt 1002 * enable bit. 1003 */ 1004 if ((intmask & SDHSTS_DATA_FLAG) && 1005 (host->hcfg & SDHCFG_DATA_IRPT_EN)) { 1006 bcm2835_data_irq(host, intmask); 1007 host->irq_data = true; 1008 result = IRQ_WAKE_THREAD; 1009 } 1010 1011 spin_unlock(&host->lock); 1012 1013 return result; 1014 } 1015 1016 static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id) 1017 { 1018 struct bcm2835_host *host = dev_id; 1019 unsigned long flags; 1020 bool block, busy, data; 1021 1022 spin_lock_irqsave(&host->lock, flags); 1023 1024 block = host->irq_block; 1025 busy = host->irq_busy; 1026 data = host->irq_data; 1027 host->irq_block = false; 1028 host->irq_busy = false; 1029 host->irq_data = false; 1030 1031 spin_unlock_irqrestore(&host->lock, flags); 1032 1033 mutex_lock(&host->mutex); 1034 1035 if (block) 1036 bcm2835_block_irq(host); 1037 if (busy) 1038 bcm2835_busy_irq(host); 1039 if (data) 1040 bcm2835_data_threaded_irq(host); 1041 1042 mutex_unlock(&host->mutex); 1043 1044 return IRQ_HANDLED; 1045 } 1046 1047 static void bcm2835_dma_complete_work(struct work_struct *work) 1048 { 1049 struct bcm2835_host *host = 1050 container_of(work, struct bcm2835_host, dma_work); 1051 struct mmc_data *data; 1052 1053 mutex_lock(&host->mutex); 1054 1055 data = host->data; 1056 1057 if (host->dma_chan) { 1058 dma_unmap_sg(host->dma_chan->device->dev, 1059 data->sg, data->sg_len, 1060 host->dma_dir); 1061 1062 host->dma_chan = NULL; 1063 } 1064 1065 if (host->drain_words) { 1066 void *page; 1067 u32 *buf; 1068 1069 if (host->drain_offset & PAGE_MASK) { 1070 host->drain_page += host->drain_offset >> PAGE_SHIFT; 1071 host->drain_offset &= ~PAGE_MASK; 1072 } 1073 page = kmap_local_page(host->drain_page); 1074 buf = page + host->drain_offset; 1075 1076 while (host->drain_words) { 1077 u32 edm = readl(host->ioaddr + SDEDM); 1078 1079 if ((edm >> 4) & 0x1f) 1080 *(buf++) = readl(host->ioaddr + SDDATA); 1081 host->drain_words--; 1082 } 1083 1084 kunmap_local(page); 1085 } 1086 1087 bcm2835_finish_data(host); 1088 1089 mutex_unlock(&host->mutex); 1090 } 1091 1092 static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock) 1093 { 1094 struct mmc_host *mmc = mmc_from_priv(host); 1095 int div; 1096 1097 /* The SDCDIV register has 11 bits, and holds (div - 2). But 1098 * in data mode the max is 50MHz wihout a minimum, and only 1099 * the bottom 3 bits are used. Since the switch over is 1100 * automatic (unless we have marked the card as slow...), 1101 * chosen values have to make sense in both modes. Ident mode 1102 * must be 100-400KHz, so can range check the requested 1103 * clock. CMD15 must be used to return to data mode, so this 1104 * can be monitored. 1105 * 1106 * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz 1107 * 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz 1108 * 1109 * 623->400KHz/27.8MHz 1110 * reset value (507)->491159/50MHz 1111 * 1112 * BUT, the 3-bit clock divisor in data mode is too small if 1113 * the core clock is higher than 250MHz, so instead use the 1114 * SLOW_CARD configuration bit to force the use of the ident 1115 * clock divisor at all times. 1116 */ 1117 1118 if (clock < 100000) { 1119 /* Can't stop the clock, but make it as slow as possible 1120 * to show willing 1121 */ 1122 host->cdiv = SDCDIV_MAX_CDIV; 1123 writel(host->cdiv, host->ioaddr + SDCDIV); 1124 return; 1125 } 1126 1127 div = host->max_clk / clock; 1128 if (div < 2) 1129 div = 2; 1130 if ((host->max_clk / div) > clock) 1131 div++; 1132 div -= 2; 1133 1134 if (div > SDCDIV_MAX_CDIV) 1135 div = SDCDIV_MAX_CDIV; 1136 1137 clock = host->max_clk / (div + 2); 1138 mmc->actual_clock = clock; 1139 1140 /* Calibrate some delays */ 1141 1142 host->ns_per_fifo_word = (1000000000 / clock) * 1143 ((mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32); 1144 1145 host->cdiv = div; 1146 writel(host->cdiv, host->ioaddr + SDCDIV); 1147 1148 /* Set the timeout to 500ms */ 1149 writel(mmc->actual_clock / 2, host->ioaddr + SDTOUT); 1150 } 1151 1152 static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq) 1153 { 1154 struct bcm2835_host *host = mmc_priv(mmc); 1155 struct device *dev = &host->pdev->dev; 1156 u32 edm, fsm; 1157 1158 /* Reset the error statuses in case this is a retry */ 1159 if (mrq->sbc) 1160 mrq->sbc->error = 0; 1161 if (mrq->cmd) 1162 mrq->cmd->error = 0; 1163 if (mrq->data) 1164 mrq->data->error = 0; 1165 if (mrq->stop) 1166 mrq->stop->error = 0; 1167 1168 if (mrq->data && !is_power_of_2(mrq->data->blksz)) { 1169 dev_err(dev, "unsupported block size (%d bytes)\n", 1170 mrq->data->blksz); 1171 1172 if (mrq->cmd) 1173 mrq->cmd->error = -EINVAL; 1174 1175 mmc_request_done(mmc, mrq); 1176 return; 1177 } 1178 1179 mutex_lock(&host->mutex); 1180 1181 WARN_ON(host->mrq); 1182 host->mrq = mrq; 1183 1184 edm = readl(host->ioaddr + SDEDM); 1185 fsm = edm & SDEDM_FSM_MASK; 1186 1187 if ((fsm != SDEDM_FSM_IDENTMODE) && 1188 (fsm != SDEDM_FSM_DATAMODE)) { 1189 dev_err(dev, "previous command (%d) not complete (EDM %08x)\n", 1190 readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK, 1191 edm); 1192 bcm2835_dumpregs(host); 1193 1194 if (mrq->cmd) 1195 mrq->cmd->error = -EILSEQ; 1196 1197 bcm2835_finish_request(host); 1198 mutex_unlock(&host->mutex); 1199 return; 1200 } 1201 1202 if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD)) 1203 bcm2835_prepare_dma(host, mrq->data); 1204 1205 host->use_sbc = !!mrq->sbc && host->mrq->data && 1206 (host->mrq->data->flags & MMC_DATA_READ); 1207 if (host->use_sbc) { 1208 if (bcm2835_send_command(host, mrq->sbc)) { 1209 if (!host->use_busy) 1210 bcm2835_finish_command(host); 1211 } 1212 } else if (mrq->cmd && bcm2835_send_command(host, mrq->cmd)) { 1213 if (host->data && host->dma_desc) { 1214 /* DMA transfer starts now, PIO starts after irq */ 1215 bcm2835_start_dma(host); 1216 } 1217 1218 if (!host->use_busy) 1219 bcm2835_finish_command(host); 1220 } 1221 1222 mutex_unlock(&host->mutex); 1223 } 1224 1225 static void bcm2835_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) 1226 { 1227 struct bcm2835_host *host = mmc_priv(mmc); 1228 1229 mutex_lock(&host->mutex); 1230 1231 if (!ios->clock || ios->clock != host->clock) { 1232 bcm2835_set_clock(host, ios->clock); 1233 host->clock = ios->clock; 1234 } 1235 1236 /* set bus width */ 1237 host->hcfg &= ~SDHCFG_WIDE_EXT_BUS; 1238 if (ios->bus_width == MMC_BUS_WIDTH_4) 1239 host->hcfg |= SDHCFG_WIDE_EXT_BUS; 1240 1241 host->hcfg |= SDHCFG_WIDE_INT_BUS; 1242 1243 /* Disable clever clock switching, to cope with fast core clocks */ 1244 host->hcfg |= SDHCFG_SLOW_CARD; 1245 1246 writel(host->hcfg, host->ioaddr + SDHCFG); 1247 1248 mutex_unlock(&host->mutex); 1249 } 1250 1251 static const struct mmc_host_ops bcm2835_ops = { 1252 .request = bcm2835_request, 1253 .set_ios = bcm2835_set_ios, 1254 .card_hw_reset = bcm2835_reset, 1255 }; 1256 1257 static int bcm2835_add_host(struct bcm2835_host *host) 1258 { 1259 struct mmc_host *mmc = mmc_from_priv(host); 1260 struct device *dev = &host->pdev->dev; 1261 char pio_limit_string[20]; 1262 int ret; 1263 1264 if (!mmc->f_max || mmc->f_max > host->max_clk) 1265 mmc->f_max = host->max_clk; 1266 mmc->f_min = host->max_clk / SDCDIV_MAX_CDIV; 1267 1268 mmc->max_busy_timeout = ~0 / (mmc->f_max / 1000); 1269 1270 dev_dbg(dev, "f_max %d, f_min %d, max_busy_timeout %d\n", 1271 mmc->f_max, mmc->f_min, mmc->max_busy_timeout); 1272 1273 /* host controller capabilities */ 1274 mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED | 1275 MMC_CAP_NEEDS_POLL | MMC_CAP_HW_RESET | MMC_CAP_CMD23; 1276 1277 spin_lock_init(&host->lock); 1278 mutex_init(&host->mutex); 1279 1280 if (!host->dma_chan_rxtx) { 1281 dev_warn(dev, "unable to initialise DMA channel. Falling back to PIO\n"); 1282 host->use_dma = false; 1283 } else { 1284 host->use_dma = true; 1285 1286 host->dma_cfg_tx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1287 host->dma_cfg_tx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1288 host->dma_cfg_tx.direction = DMA_MEM_TO_DEV; 1289 host->dma_cfg_tx.src_addr = 0; 1290 host->dma_cfg_tx.dst_addr = host->phys_addr + SDDATA; 1291 1292 host->dma_cfg_rx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1293 host->dma_cfg_rx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1294 host->dma_cfg_rx.direction = DMA_DEV_TO_MEM; 1295 host->dma_cfg_rx.src_addr = host->phys_addr + SDDATA; 1296 host->dma_cfg_rx.dst_addr = 0; 1297 1298 if (dmaengine_slave_config(host->dma_chan_rxtx, 1299 &host->dma_cfg_tx) != 0 || 1300 dmaengine_slave_config(host->dma_chan_rxtx, 1301 &host->dma_cfg_rx) != 0) 1302 host->use_dma = false; 1303 } 1304 1305 mmc->max_segs = 128; 1306 mmc->max_req_size = min_t(size_t, 524288, dma_max_mapping_size(dev)); 1307 mmc->max_seg_size = mmc->max_req_size; 1308 mmc->max_blk_size = 1024; 1309 mmc->max_blk_count = 65535; 1310 1311 /* report supported voltage ranges */ 1312 mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34; 1313 1314 INIT_WORK(&host->dma_work, bcm2835_dma_complete_work); 1315 INIT_DELAYED_WORK(&host->timeout_work, bcm2835_timeout); 1316 1317 /* Set interrupt enables */ 1318 host->hcfg = SDHCFG_BUSY_IRPT_EN; 1319 1320 bcm2835_reset_internal(host); 1321 1322 ret = request_threaded_irq(host->irq, bcm2835_irq, 1323 bcm2835_threaded_irq, 1324 0, mmc_hostname(mmc), host); 1325 if (ret) { 1326 dev_err(dev, "failed to request IRQ %d: %d\n", host->irq, ret); 1327 return ret; 1328 } 1329 1330 ret = mmc_add_host(mmc); 1331 if (ret) { 1332 free_irq(host->irq, host); 1333 return ret; 1334 } 1335 1336 pio_limit_string[0] = '\0'; 1337 if (host->use_dma && (PIO_THRESHOLD > 0)) 1338 sprintf(pio_limit_string, " (>%d)", PIO_THRESHOLD); 1339 dev_info(dev, "loaded - DMA %s%s\n", 1340 host->use_dma ? "enabled" : "disabled", pio_limit_string); 1341 1342 return 0; 1343 } 1344 1345 static int bcm2835_probe(struct platform_device *pdev) 1346 { 1347 struct device *dev = &pdev->dev; 1348 struct clk *clk; 1349 struct bcm2835_host *host; 1350 struct mmc_host *mmc; 1351 const __be32 *regaddr_p; 1352 int ret; 1353 1354 dev_dbg(dev, "%s\n", __func__); 1355 mmc = mmc_alloc_host(sizeof(*host), dev); 1356 if (!mmc) 1357 return -ENOMEM; 1358 1359 mmc->ops = &bcm2835_ops; 1360 host = mmc_priv(mmc); 1361 host->pdev = pdev; 1362 spin_lock_init(&host->lock); 1363 1364 host->ioaddr = devm_platform_ioremap_resource(pdev, 0); 1365 if (IS_ERR(host->ioaddr)) { 1366 ret = PTR_ERR(host->ioaddr); 1367 goto err; 1368 } 1369 1370 /* Parse OF address directly to get the physical address for 1371 * DMA to our registers. 1372 */ 1373 regaddr_p = of_get_address(pdev->dev.of_node, 0, NULL, NULL); 1374 if (!regaddr_p) { 1375 dev_err(dev, "Can't get phys address\n"); 1376 ret = -EINVAL; 1377 goto err; 1378 } 1379 1380 host->phys_addr = be32_to_cpup(regaddr_p); 1381 1382 host->dma_chan = NULL; 1383 host->dma_desc = NULL; 1384 1385 host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx"); 1386 if (IS_ERR(host->dma_chan_rxtx)) { 1387 ret = PTR_ERR(host->dma_chan_rxtx); 1388 host->dma_chan_rxtx = NULL; 1389 1390 if (ret == -EPROBE_DEFER) 1391 goto err; 1392 1393 /* Ignore errors to fall back to PIO mode */ 1394 } 1395 1396 1397 clk = devm_clk_get(dev, NULL); 1398 if (IS_ERR(clk)) { 1399 ret = dev_err_probe(dev, PTR_ERR(clk), "could not get clk\n"); 1400 goto err; 1401 } 1402 1403 host->max_clk = clk_get_rate(clk); 1404 1405 host->irq = platform_get_irq(pdev, 0); 1406 if (host->irq <= 0) { 1407 ret = -EINVAL; 1408 goto err; 1409 } 1410 1411 ret = mmc_of_parse(mmc); 1412 if (ret) 1413 goto err; 1414 1415 ret = bcm2835_add_host(host); 1416 if (ret) 1417 goto err; 1418 1419 platform_set_drvdata(pdev, host); 1420 1421 dev_dbg(dev, "%s -> OK\n", __func__); 1422 1423 return 0; 1424 1425 err: 1426 dev_dbg(dev, "%s -> err %d\n", __func__, ret); 1427 if (host->dma_chan_rxtx) 1428 dma_release_channel(host->dma_chan_rxtx); 1429 mmc_free_host(mmc); 1430 1431 return ret; 1432 } 1433 1434 static int bcm2835_remove(struct platform_device *pdev) 1435 { 1436 struct bcm2835_host *host = platform_get_drvdata(pdev); 1437 struct mmc_host *mmc = mmc_from_priv(host); 1438 1439 mmc_remove_host(mmc); 1440 1441 writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD); 1442 1443 free_irq(host->irq, host); 1444 1445 cancel_work_sync(&host->dma_work); 1446 cancel_delayed_work_sync(&host->timeout_work); 1447 1448 if (host->dma_chan_rxtx) 1449 dma_release_channel(host->dma_chan_rxtx); 1450 1451 mmc_free_host(mmc); 1452 1453 return 0; 1454 } 1455 1456 static const struct of_device_id bcm2835_match[] = { 1457 { .compatible = "brcm,bcm2835-sdhost" }, 1458 { } 1459 }; 1460 MODULE_DEVICE_TABLE(of, bcm2835_match); 1461 1462 static struct platform_driver bcm2835_driver = { 1463 .probe = bcm2835_probe, 1464 .remove = bcm2835_remove, 1465 .driver = { 1466 .name = "sdhost-bcm2835", 1467 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1468 .of_match_table = bcm2835_match, 1469 }, 1470 }; 1471 module_platform_driver(bcm2835_driver); 1472 1473 MODULE_ALIAS("platform:sdhost-bcm2835"); 1474 MODULE_DESCRIPTION("BCM2835 SDHost driver"); 1475 MODULE_LICENSE("GPL v2"); 1476 MODULE_AUTHOR("Phil Elwell"); 1477