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 unsigned long flags; 331 size_t blksize; 332 unsigned long wait_max; 333 334 blksize = host->data->blksz; 335 336 wait_max = jiffies + msecs_to_jiffies(500); 337 338 local_irq_save(flags); 339 340 while (blksize) { 341 int copy_words; 342 u32 hsts = 0; 343 size_t len; 344 u32 *buf; 345 346 if (!sg_miter_next(&host->sg_miter)) { 347 host->data->error = -EINVAL; 348 break; 349 } 350 351 len = min(host->sg_miter.length, blksize); 352 if (len % 4) { 353 host->data->error = -EINVAL; 354 break; 355 } 356 357 blksize -= len; 358 host->sg_miter.consumed = len; 359 360 buf = (u32 *)host->sg_miter.addr; 361 362 copy_words = len / 4; 363 364 while (copy_words) { 365 int burst_words, words; 366 u32 edm; 367 368 burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words); 369 edm = readl(host->ioaddr + SDEDM); 370 if (is_read) 371 words = ((edm >> 4) & 0x1f); 372 else 373 words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f); 374 375 if (words < burst_words) { 376 int fsm_state = (edm & SDEDM_FSM_MASK); 377 struct device *dev = &host->pdev->dev; 378 379 if ((is_read && 380 (fsm_state != SDEDM_FSM_READDATA && 381 fsm_state != SDEDM_FSM_READWAIT && 382 fsm_state != SDEDM_FSM_READCRC)) || 383 (!is_read && 384 (fsm_state != SDEDM_FSM_WRITEDATA && 385 fsm_state != SDEDM_FSM_WRITESTART1 && 386 fsm_state != SDEDM_FSM_WRITESTART2))) { 387 hsts = readl(host->ioaddr + SDHSTS); 388 dev_err(dev, "fsm %x, hsts %08x\n", 389 fsm_state, hsts); 390 if (hsts & SDHSTS_ERROR_MASK) 391 break; 392 } 393 394 if (time_after(jiffies, wait_max)) { 395 dev_err(dev, "PIO %s timeout - EDM %08x\n", 396 is_read ? "read" : "write", 397 edm); 398 hsts = SDHSTS_REW_TIME_OUT; 399 break; 400 } 401 ndelay((burst_words - words) * 402 host->ns_per_fifo_word); 403 continue; 404 } else if (words > copy_words) { 405 words = copy_words; 406 } 407 408 copy_words -= words; 409 410 while (words) { 411 if (is_read) 412 *(buf++) = readl(host->ioaddr + SDDATA); 413 else 414 writel(*(buf++), host->ioaddr + SDDATA); 415 words--; 416 } 417 } 418 419 if (hsts & SDHSTS_ERROR_MASK) 420 break; 421 } 422 423 sg_miter_stop(&host->sg_miter); 424 425 local_irq_restore(flags); 426 } 427 428 static void bcm2835_transfer_pio(struct bcm2835_host *host) 429 { 430 struct device *dev = &host->pdev->dev; 431 u32 sdhsts; 432 bool is_read; 433 434 is_read = (host->data->flags & MMC_DATA_READ) != 0; 435 bcm2835_transfer_block_pio(host, is_read); 436 437 sdhsts = readl(host->ioaddr + SDHSTS); 438 if (sdhsts & (SDHSTS_CRC16_ERROR | 439 SDHSTS_CRC7_ERROR | 440 SDHSTS_FIFO_ERROR)) { 441 dev_err(dev, "%s transfer error - HSTS %08x\n", 442 is_read ? "read" : "write", sdhsts); 443 host->data->error = -EILSEQ; 444 } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT | 445 SDHSTS_REW_TIME_OUT))) { 446 dev_err(dev, "%s timeout error - HSTS %08x\n", 447 is_read ? "read" : "write", sdhsts); 448 host->data->error = -ETIMEDOUT; 449 } 450 } 451 452 static 453 void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data) 454 { 455 int sg_len, dir_data, dir_slave; 456 struct dma_async_tx_descriptor *desc = NULL; 457 struct dma_chan *dma_chan; 458 459 dma_chan = host->dma_chan_rxtx; 460 if (data->flags & MMC_DATA_READ) { 461 dir_data = DMA_FROM_DEVICE; 462 dir_slave = DMA_DEV_TO_MEM; 463 } else { 464 dir_data = DMA_TO_DEVICE; 465 dir_slave = DMA_MEM_TO_DEV; 466 } 467 468 /* The block doesn't manage the FIFO DREQs properly for 469 * multi-block transfers, so don't attempt to DMA the final 470 * few words. Unfortunately this requires the final sg entry 471 * to be trimmed. N.B. This code demands that the overspill 472 * is contained in a single sg entry. 473 */ 474 475 host->drain_words = 0; 476 if ((data->blocks > 1) && (dir_data == DMA_FROM_DEVICE)) { 477 struct scatterlist *sg; 478 u32 len; 479 int i; 480 481 len = min((u32)(FIFO_READ_THRESHOLD - 1) * 4, 482 (u32)data->blocks * data->blksz); 483 484 for_each_sg(data->sg, sg, data->sg_len, i) { 485 if (sg_is_last(sg)) { 486 WARN_ON(sg->length < len); 487 sg->length -= len; 488 host->drain_page = sg_page(sg); 489 host->drain_offset = sg->offset + sg->length; 490 } 491 } 492 host->drain_words = len / 4; 493 } 494 495 /* The parameters have already been validated, so this will not fail */ 496 (void)dmaengine_slave_config(dma_chan, 497 (dir_data == DMA_FROM_DEVICE) ? 498 &host->dma_cfg_rx : 499 &host->dma_cfg_tx); 500 501 sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len, 502 dir_data); 503 if (!sg_len) 504 return; 505 506 desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave, 507 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 508 509 if (!desc) { 510 dma_unmap_sg(dma_chan->device->dev, data->sg, sg_len, dir_data); 511 return; 512 } 513 514 desc->callback = bcm2835_dma_complete; 515 desc->callback_param = host; 516 host->dma_desc = desc; 517 host->dma_chan = dma_chan; 518 host->dma_dir = dir_data; 519 } 520 521 static void bcm2835_start_dma(struct bcm2835_host *host) 522 { 523 dmaengine_submit(host->dma_desc); 524 dma_async_issue_pending(host->dma_chan); 525 } 526 527 static void bcm2835_set_transfer_irqs(struct bcm2835_host *host) 528 { 529 u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN | 530 SDHCFG_BUSY_IRPT_EN; 531 532 if (host->dma_desc) { 533 host->hcfg = (host->hcfg & ~all_irqs) | 534 SDHCFG_BUSY_IRPT_EN; 535 } else { 536 host->hcfg = (host->hcfg & ~all_irqs) | 537 SDHCFG_DATA_IRPT_EN | 538 SDHCFG_BUSY_IRPT_EN; 539 } 540 541 writel(host->hcfg, host->ioaddr + SDHCFG); 542 } 543 544 static 545 void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_command *cmd) 546 { 547 struct mmc_data *data = cmd->data; 548 549 WARN_ON(host->data); 550 551 host->data = data; 552 if (!data) 553 return; 554 555 host->data_complete = false; 556 host->data->bytes_xfered = 0; 557 558 if (!host->dma_desc) { 559 /* Use PIO */ 560 int flags = SG_MITER_ATOMIC; 561 562 if (data->flags & MMC_DATA_READ) 563 flags |= SG_MITER_TO_SG; 564 else 565 flags |= SG_MITER_FROM_SG; 566 sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags); 567 host->blocks = data->blocks; 568 } 569 570 bcm2835_set_transfer_irqs(host); 571 572 writel(data->blksz, host->ioaddr + SDHBCT); 573 writel(data->blocks, host->ioaddr + SDHBLC); 574 } 575 576 static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host, u32 max_ms) 577 { 578 struct device *dev = &host->pdev->dev; 579 u32 value; 580 int ret; 581 582 ret = readl_poll_timeout(host->ioaddr + SDCMD, value, 583 !(value & SDCMD_NEW_FLAG), 1, 10); 584 if (ret == -ETIMEDOUT) 585 /* if it takes a while make poll interval bigger */ 586 ret = readl_poll_timeout(host->ioaddr + SDCMD, value, 587 !(value & SDCMD_NEW_FLAG), 588 10, max_ms * 1000); 589 if (ret == -ETIMEDOUT) 590 dev_err(dev, "%s: timeout (%d ms)\n", __func__, max_ms); 591 592 return value; 593 } 594 595 static void bcm2835_finish_request(struct bcm2835_host *host) 596 { 597 struct dma_chan *terminate_chan = NULL; 598 struct mmc_request *mrq; 599 600 cancel_delayed_work(&host->timeout_work); 601 602 mrq = host->mrq; 603 604 host->mrq = NULL; 605 host->cmd = NULL; 606 host->data = NULL; 607 608 host->dma_desc = NULL; 609 terminate_chan = host->dma_chan; 610 host->dma_chan = NULL; 611 612 if (terminate_chan) { 613 int err = dmaengine_terminate_all(terminate_chan); 614 615 if (err) 616 dev_err(&host->pdev->dev, 617 "failed to terminate DMA (%d)\n", err); 618 } 619 620 mmc_request_done(mmc_from_priv(host), mrq); 621 } 622 623 static 624 bool bcm2835_send_command(struct bcm2835_host *host, struct mmc_command *cmd) 625 { 626 struct device *dev = &host->pdev->dev; 627 u32 sdcmd, sdhsts; 628 unsigned long timeout; 629 630 WARN_ON(host->cmd); 631 632 sdcmd = bcm2835_read_wait_sdcmd(host, 100); 633 if (sdcmd & SDCMD_NEW_FLAG) { 634 dev_err(dev, "previous command never completed.\n"); 635 bcm2835_dumpregs(host); 636 cmd->error = -EILSEQ; 637 bcm2835_finish_request(host); 638 return false; 639 } 640 641 if (!cmd->data && cmd->busy_timeout > 9000) 642 timeout = DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ; 643 else 644 timeout = 10 * HZ; 645 schedule_delayed_work(&host->timeout_work, timeout); 646 647 host->cmd = cmd; 648 649 /* Clear any error flags */ 650 sdhsts = readl(host->ioaddr + SDHSTS); 651 if (sdhsts & SDHSTS_ERROR_MASK) 652 writel(sdhsts, host->ioaddr + SDHSTS); 653 654 if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) { 655 dev_err(dev, "unsupported response type!\n"); 656 cmd->error = -EINVAL; 657 bcm2835_finish_request(host); 658 return false; 659 } 660 661 bcm2835_prepare_data(host, cmd); 662 663 writel(cmd->arg, host->ioaddr + SDARG); 664 665 sdcmd = cmd->opcode & SDCMD_CMD_MASK; 666 667 host->use_busy = false; 668 if (!(cmd->flags & MMC_RSP_PRESENT)) { 669 sdcmd |= SDCMD_NO_RESPONSE; 670 } else { 671 if (cmd->flags & MMC_RSP_136) 672 sdcmd |= SDCMD_LONG_RESPONSE; 673 if (cmd->flags & MMC_RSP_BUSY) { 674 sdcmd |= SDCMD_BUSYWAIT; 675 host->use_busy = true; 676 } 677 } 678 679 if (cmd->data) { 680 if (cmd->data->flags & MMC_DATA_WRITE) 681 sdcmd |= SDCMD_WRITE_CMD; 682 if (cmd->data->flags & MMC_DATA_READ) 683 sdcmd |= SDCMD_READ_CMD; 684 } 685 686 writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD); 687 688 return true; 689 } 690 691 static void bcm2835_transfer_complete(struct bcm2835_host *host) 692 { 693 struct mmc_data *data; 694 695 WARN_ON(!host->data_complete); 696 697 data = host->data; 698 host->data = NULL; 699 700 /* Need to send CMD12 if - 701 * a) open-ended multiblock transfer (no CMD23) 702 * b) error in multiblock transfer 703 */ 704 if (host->mrq->stop && (data->error || !host->use_sbc)) { 705 if (bcm2835_send_command(host, host->mrq->stop)) { 706 /* No busy, so poll for completion */ 707 if (!host->use_busy) 708 bcm2835_finish_command(host); 709 } 710 } else { 711 bcm2835_wait_transfer_complete(host); 712 bcm2835_finish_request(host); 713 } 714 } 715 716 static void bcm2835_finish_data(struct bcm2835_host *host) 717 { 718 struct device *dev = &host->pdev->dev; 719 struct mmc_data *data; 720 721 data = host->data; 722 723 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); 724 writel(host->hcfg, host->ioaddr + SDHCFG); 725 726 data->bytes_xfered = data->error ? 0 : (data->blksz * data->blocks); 727 728 host->data_complete = true; 729 730 if (host->cmd) { 731 /* Data managed to finish before the 732 * command completed. Make sure we do 733 * things in the proper order. 734 */ 735 dev_dbg(dev, "Finished early - HSTS %08x\n", 736 readl(host->ioaddr + SDHSTS)); 737 } else { 738 bcm2835_transfer_complete(host); 739 } 740 } 741 742 static void bcm2835_finish_command(struct bcm2835_host *host) 743 { 744 struct device *dev = &host->pdev->dev; 745 struct mmc_command *cmd = host->cmd; 746 u32 sdcmd; 747 748 sdcmd = bcm2835_read_wait_sdcmd(host, 100); 749 750 /* Check for errors */ 751 if (sdcmd & SDCMD_NEW_FLAG) { 752 dev_err(dev, "command never completed.\n"); 753 bcm2835_dumpregs(host); 754 host->cmd->error = -EIO; 755 bcm2835_finish_request(host); 756 return; 757 } else if (sdcmd & SDCMD_FAIL_FLAG) { 758 u32 sdhsts = readl(host->ioaddr + SDHSTS); 759 760 /* Clear the errors */ 761 writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS); 762 763 if (!(sdhsts & SDHSTS_CRC7_ERROR) || 764 (host->cmd->opcode != MMC_SEND_OP_COND)) { 765 u32 edm, fsm; 766 767 if (sdhsts & SDHSTS_CMD_TIME_OUT) { 768 host->cmd->error = -ETIMEDOUT; 769 } else { 770 dev_err(dev, "unexpected command %d error\n", 771 host->cmd->opcode); 772 bcm2835_dumpregs(host); 773 host->cmd->error = -EILSEQ; 774 } 775 edm = readl(host->ioaddr + SDEDM); 776 fsm = edm & SDEDM_FSM_MASK; 777 if (fsm == SDEDM_FSM_READWAIT || 778 fsm == SDEDM_FSM_WRITESTART1) 779 /* Kick the FSM out of its wait */ 780 writel(edm | SDEDM_FORCE_DATA_MODE, 781 host->ioaddr + SDEDM); 782 bcm2835_finish_request(host); 783 return; 784 } 785 } 786 787 if (cmd->flags & MMC_RSP_PRESENT) { 788 if (cmd->flags & MMC_RSP_136) { 789 int i; 790 791 for (i = 0; i < 4; i++) { 792 cmd->resp[3 - i] = 793 readl(host->ioaddr + SDRSP0 + i * 4); 794 } 795 } else { 796 cmd->resp[0] = readl(host->ioaddr + SDRSP0); 797 } 798 } 799 800 if (cmd == host->mrq->sbc) { 801 /* Finished CMD23, now send actual command. */ 802 host->cmd = NULL; 803 if (bcm2835_send_command(host, host->mrq->cmd)) { 804 if (host->data && host->dma_desc) 805 /* DMA transfer starts now, PIO starts 806 * after irq 807 */ 808 bcm2835_start_dma(host); 809 810 if (!host->use_busy) 811 bcm2835_finish_command(host); 812 } 813 } else if (cmd == host->mrq->stop) { 814 /* Finished CMD12 */ 815 bcm2835_finish_request(host); 816 } else { 817 /* Processed actual command. */ 818 host->cmd = NULL; 819 if (!host->data) 820 bcm2835_finish_request(host); 821 else if (host->data_complete) 822 bcm2835_transfer_complete(host); 823 } 824 } 825 826 static void bcm2835_timeout(struct work_struct *work) 827 { 828 struct delayed_work *d = to_delayed_work(work); 829 struct bcm2835_host *host = 830 container_of(d, struct bcm2835_host, timeout_work); 831 struct device *dev = &host->pdev->dev; 832 833 mutex_lock(&host->mutex); 834 835 if (host->mrq) { 836 dev_err(dev, "timeout waiting for hardware interrupt.\n"); 837 bcm2835_dumpregs(host); 838 839 bcm2835_reset(mmc_from_priv(host)); 840 841 if (host->data) { 842 host->data->error = -ETIMEDOUT; 843 bcm2835_finish_data(host); 844 } else { 845 if (host->cmd) 846 host->cmd->error = -ETIMEDOUT; 847 else 848 host->mrq->cmd->error = -ETIMEDOUT; 849 850 bcm2835_finish_request(host); 851 } 852 } 853 854 mutex_unlock(&host->mutex); 855 } 856 857 static bool bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask) 858 { 859 struct device *dev = &host->pdev->dev; 860 861 if (!(intmask & SDHSTS_ERROR_MASK)) 862 return false; 863 864 if (!host->cmd) 865 return true; 866 867 dev_err(dev, "sdhost_busy_irq: intmask %08x\n", intmask); 868 if (intmask & SDHSTS_CRC7_ERROR) { 869 host->cmd->error = -EILSEQ; 870 } else if (intmask & (SDHSTS_CRC16_ERROR | 871 SDHSTS_FIFO_ERROR)) { 872 if (host->mrq->data) 873 host->mrq->data->error = -EILSEQ; 874 else 875 host->cmd->error = -EILSEQ; 876 } else if (intmask & SDHSTS_REW_TIME_OUT) { 877 if (host->mrq->data) 878 host->mrq->data->error = -ETIMEDOUT; 879 else 880 host->cmd->error = -ETIMEDOUT; 881 } else if (intmask & SDHSTS_CMD_TIME_OUT) { 882 host->cmd->error = -ETIMEDOUT; 883 } 884 bcm2835_dumpregs(host); 885 return true; 886 } 887 888 static void bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask) 889 { 890 if (!host->data) 891 return; 892 if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR)) 893 host->data->error = -EILSEQ; 894 if (intmask & SDHSTS_REW_TIME_OUT) 895 host->data->error = -ETIMEDOUT; 896 } 897 898 static void bcm2835_busy_irq(struct bcm2835_host *host) 899 { 900 if (WARN_ON(!host->cmd)) { 901 bcm2835_dumpregs(host); 902 return; 903 } 904 905 if (WARN_ON(!host->use_busy)) { 906 bcm2835_dumpregs(host); 907 return; 908 } 909 host->use_busy = false; 910 911 bcm2835_finish_command(host); 912 } 913 914 static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask) 915 { 916 /* There are no dedicated data/space available interrupt 917 * status bits, so it is necessary to use the single shared 918 * data/space available FIFO status bits. It is therefore not 919 * an error to get here when there is no data transfer in 920 * progress. 921 */ 922 if (!host->data) 923 return; 924 925 bcm2835_check_data_error(host, intmask); 926 if (host->data->error) 927 goto finished; 928 929 if (host->data->flags & MMC_DATA_WRITE) { 930 /* Use the block interrupt for writes after the first block */ 931 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN); 932 host->hcfg |= SDHCFG_BLOCK_IRPT_EN; 933 writel(host->hcfg, host->ioaddr + SDHCFG); 934 bcm2835_transfer_pio(host); 935 } else { 936 bcm2835_transfer_pio(host); 937 host->blocks--; 938 if ((host->blocks == 0) || host->data->error) 939 goto finished; 940 } 941 return; 942 943 finished: 944 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); 945 writel(host->hcfg, host->ioaddr + SDHCFG); 946 } 947 948 static void bcm2835_data_threaded_irq(struct bcm2835_host *host) 949 { 950 if (!host->data) 951 return; 952 if ((host->blocks == 0) || host->data->error) 953 bcm2835_finish_data(host); 954 } 955 956 static void bcm2835_block_irq(struct bcm2835_host *host) 957 { 958 if (WARN_ON(!host->data)) { 959 bcm2835_dumpregs(host); 960 return; 961 } 962 963 if (!host->dma_desc) { 964 WARN_ON(!host->blocks); 965 if (host->data->error || (--host->blocks == 0)) 966 bcm2835_finish_data(host); 967 else 968 bcm2835_transfer_pio(host); 969 } else if (host->data->flags & MMC_DATA_WRITE) { 970 bcm2835_finish_data(host); 971 } 972 } 973 974 static irqreturn_t bcm2835_irq(int irq, void *dev_id) 975 { 976 irqreturn_t result = IRQ_NONE; 977 struct bcm2835_host *host = dev_id; 978 u32 intmask; 979 980 spin_lock(&host->lock); 981 982 intmask = readl(host->ioaddr + SDHSTS); 983 984 writel(SDHSTS_BUSY_IRPT | 985 SDHSTS_BLOCK_IRPT | 986 SDHSTS_SDIO_IRPT | 987 SDHSTS_DATA_FLAG, 988 host->ioaddr + SDHSTS); 989 990 if (intmask & SDHSTS_BLOCK_IRPT) { 991 bcm2835_check_data_error(host, intmask); 992 host->irq_block = true; 993 result = IRQ_WAKE_THREAD; 994 } 995 996 if (intmask & SDHSTS_BUSY_IRPT) { 997 if (!bcm2835_check_cmd_error(host, intmask)) { 998 host->irq_busy = true; 999 result = IRQ_WAKE_THREAD; 1000 } else { 1001 result = IRQ_HANDLED; 1002 } 1003 } 1004 1005 /* There is no true data interrupt status bit, so it is 1006 * necessary to qualify the data flag with the interrupt 1007 * enable bit. 1008 */ 1009 if ((intmask & SDHSTS_DATA_FLAG) && 1010 (host->hcfg & SDHCFG_DATA_IRPT_EN)) { 1011 bcm2835_data_irq(host, intmask); 1012 host->irq_data = true; 1013 result = IRQ_WAKE_THREAD; 1014 } 1015 1016 spin_unlock(&host->lock); 1017 1018 return result; 1019 } 1020 1021 static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id) 1022 { 1023 struct bcm2835_host *host = dev_id; 1024 unsigned long flags; 1025 bool block, busy, data; 1026 1027 spin_lock_irqsave(&host->lock, flags); 1028 1029 block = host->irq_block; 1030 busy = host->irq_busy; 1031 data = host->irq_data; 1032 host->irq_block = false; 1033 host->irq_busy = false; 1034 host->irq_data = false; 1035 1036 spin_unlock_irqrestore(&host->lock, flags); 1037 1038 mutex_lock(&host->mutex); 1039 1040 if (block) 1041 bcm2835_block_irq(host); 1042 if (busy) 1043 bcm2835_busy_irq(host); 1044 if (data) 1045 bcm2835_data_threaded_irq(host); 1046 1047 mutex_unlock(&host->mutex); 1048 1049 return IRQ_HANDLED; 1050 } 1051 1052 static void bcm2835_dma_complete_work(struct work_struct *work) 1053 { 1054 struct bcm2835_host *host = 1055 container_of(work, struct bcm2835_host, dma_work); 1056 struct mmc_data *data; 1057 1058 mutex_lock(&host->mutex); 1059 1060 data = host->data; 1061 1062 if (host->dma_chan) { 1063 dma_unmap_sg(host->dma_chan->device->dev, 1064 data->sg, data->sg_len, 1065 host->dma_dir); 1066 1067 host->dma_chan = NULL; 1068 } 1069 1070 if (host->drain_words) { 1071 unsigned long flags; 1072 void *page; 1073 u32 *buf; 1074 1075 if (host->drain_offset & PAGE_MASK) { 1076 host->drain_page += host->drain_offset >> PAGE_SHIFT; 1077 host->drain_offset &= ~PAGE_MASK; 1078 } 1079 local_irq_save(flags); 1080 page = kmap_atomic(host->drain_page); 1081 buf = page + host->drain_offset; 1082 1083 while (host->drain_words) { 1084 u32 edm = readl(host->ioaddr + SDEDM); 1085 1086 if ((edm >> 4) & 0x1f) 1087 *(buf++) = readl(host->ioaddr + SDDATA); 1088 host->drain_words--; 1089 } 1090 1091 kunmap_atomic(page); 1092 local_irq_restore(flags); 1093 } 1094 1095 bcm2835_finish_data(host); 1096 1097 mutex_unlock(&host->mutex); 1098 } 1099 1100 static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock) 1101 { 1102 struct mmc_host *mmc = mmc_from_priv(host); 1103 int div; 1104 1105 /* The SDCDIV register has 11 bits, and holds (div - 2). But 1106 * in data mode the max is 50MHz wihout a minimum, and only 1107 * the bottom 3 bits are used. Since the switch over is 1108 * automatic (unless we have marked the card as slow...), 1109 * chosen values have to make sense in both modes. Ident mode 1110 * must be 100-400KHz, so can range check the requested 1111 * clock. CMD15 must be used to return to data mode, so this 1112 * can be monitored. 1113 * 1114 * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz 1115 * 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz 1116 * 1117 * 623->400KHz/27.8MHz 1118 * reset value (507)->491159/50MHz 1119 * 1120 * BUT, the 3-bit clock divisor in data mode is too small if 1121 * the core clock is higher than 250MHz, so instead use the 1122 * SLOW_CARD configuration bit to force the use of the ident 1123 * clock divisor at all times. 1124 */ 1125 1126 if (clock < 100000) { 1127 /* Can't stop the clock, but make it as slow as possible 1128 * to show willing 1129 */ 1130 host->cdiv = SDCDIV_MAX_CDIV; 1131 writel(host->cdiv, host->ioaddr + SDCDIV); 1132 return; 1133 } 1134 1135 div = host->max_clk / clock; 1136 if (div < 2) 1137 div = 2; 1138 if ((host->max_clk / div) > clock) 1139 div++; 1140 div -= 2; 1141 1142 if (div > SDCDIV_MAX_CDIV) 1143 div = SDCDIV_MAX_CDIV; 1144 1145 clock = host->max_clk / (div + 2); 1146 mmc->actual_clock = clock; 1147 1148 /* Calibrate some delays */ 1149 1150 host->ns_per_fifo_word = (1000000000 / clock) * 1151 ((mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32); 1152 1153 host->cdiv = div; 1154 writel(host->cdiv, host->ioaddr + SDCDIV); 1155 1156 /* Set the timeout to 500ms */ 1157 writel(mmc->actual_clock / 2, host->ioaddr + SDTOUT); 1158 } 1159 1160 static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq) 1161 { 1162 struct bcm2835_host *host = mmc_priv(mmc); 1163 struct device *dev = &host->pdev->dev; 1164 u32 edm, fsm; 1165 1166 /* Reset the error statuses in case this is a retry */ 1167 if (mrq->sbc) 1168 mrq->sbc->error = 0; 1169 if (mrq->cmd) 1170 mrq->cmd->error = 0; 1171 if (mrq->data) 1172 mrq->data->error = 0; 1173 if (mrq->stop) 1174 mrq->stop->error = 0; 1175 1176 if (mrq->data && !is_power_of_2(mrq->data->blksz)) { 1177 dev_err(dev, "unsupported block size (%d bytes)\n", 1178 mrq->data->blksz); 1179 1180 if (mrq->cmd) 1181 mrq->cmd->error = -EINVAL; 1182 1183 mmc_request_done(mmc, mrq); 1184 return; 1185 } 1186 1187 mutex_lock(&host->mutex); 1188 1189 WARN_ON(host->mrq); 1190 host->mrq = mrq; 1191 1192 edm = readl(host->ioaddr + SDEDM); 1193 fsm = edm & SDEDM_FSM_MASK; 1194 1195 if ((fsm != SDEDM_FSM_IDENTMODE) && 1196 (fsm != SDEDM_FSM_DATAMODE)) { 1197 dev_err(dev, "previous command (%d) not complete (EDM %08x)\n", 1198 readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK, 1199 edm); 1200 bcm2835_dumpregs(host); 1201 1202 if (mrq->cmd) 1203 mrq->cmd->error = -EILSEQ; 1204 1205 bcm2835_finish_request(host); 1206 mutex_unlock(&host->mutex); 1207 return; 1208 } 1209 1210 if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD)) 1211 bcm2835_prepare_dma(host, mrq->data); 1212 1213 host->use_sbc = !!mrq->sbc && host->mrq->data && 1214 (host->mrq->data->flags & MMC_DATA_READ); 1215 if (host->use_sbc) { 1216 if (bcm2835_send_command(host, mrq->sbc)) { 1217 if (!host->use_busy) 1218 bcm2835_finish_command(host); 1219 } 1220 } else if (mrq->cmd && bcm2835_send_command(host, mrq->cmd)) { 1221 if (host->data && host->dma_desc) { 1222 /* DMA transfer starts now, PIO starts after irq */ 1223 bcm2835_start_dma(host); 1224 } 1225 1226 if (!host->use_busy) 1227 bcm2835_finish_command(host); 1228 } 1229 1230 mutex_unlock(&host->mutex); 1231 } 1232 1233 static void bcm2835_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) 1234 { 1235 struct bcm2835_host *host = mmc_priv(mmc); 1236 1237 mutex_lock(&host->mutex); 1238 1239 if (!ios->clock || ios->clock != host->clock) { 1240 bcm2835_set_clock(host, ios->clock); 1241 host->clock = ios->clock; 1242 } 1243 1244 /* set bus width */ 1245 host->hcfg &= ~SDHCFG_WIDE_EXT_BUS; 1246 if (ios->bus_width == MMC_BUS_WIDTH_4) 1247 host->hcfg |= SDHCFG_WIDE_EXT_BUS; 1248 1249 host->hcfg |= SDHCFG_WIDE_INT_BUS; 1250 1251 /* Disable clever clock switching, to cope with fast core clocks */ 1252 host->hcfg |= SDHCFG_SLOW_CARD; 1253 1254 writel(host->hcfg, host->ioaddr + SDHCFG); 1255 1256 mutex_unlock(&host->mutex); 1257 } 1258 1259 static const struct mmc_host_ops bcm2835_ops = { 1260 .request = bcm2835_request, 1261 .set_ios = bcm2835_set_ios, 1262 .hw_reset = bcm2835_reset, 1263 }; 1264 1265 static int bcm2835_add_host(struct bcm2835_host *host) 1266 { 1267 struct mmc_host *mmc = mmc_from_priv(host); 1268 struct device *dev = &host->pdev->dev; 1269 char pio_limit_string[20]; 1270 int ret; 1271 1272 if (!mmc->f_max || mmc->f_max > host->max_clk) 1273 mmc->f_max = host->max_clk; 1274 mmc->f_min = host->max_clk / SDCDIV_MAX_CDIV; 1275 1276 mmc->max_busy_timeout = ~0 / (mmc->f_max / 1000); 1277 1278 dev_dbg(dev, "f_max %d, f_min %d, max_busy_timeout %d\n", 1279 mmc->f_max, mmc->f_min, mmc->max_busy_timeout); 1280 1281 /* host controller capabilities */ 1282 mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED | 1283 MMC_CAP_NEEDS_POLL | MMC_CAP_HW_RESET | MMC_CAP_CMD23; 1284 1285 spin_lock_init(&host->lock); 1286 mutex_init(&host->mutex); 1287 1288 if (!host->dma_chan_rxtx) { 1289 dev_warn(dev, "unable to initialise DMA channel. Falling back to PIO\n"); 1290 host->use_dma = false; 1291 } else { 1292 host->use_dma = true; 1293 1294 host->dma_cfg_tx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1295 host->dma_cfg_tx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1296 host->dma_cfg_tx.slave_id = 13; /* DREQ channel */ 1297 host->dma_cfg_tx.direction = DMA_MEM_TO_DEV; 1298 host->dma_cfg_tx.src_addr = 0; 1299 host->dma_cfg_tx.dst_addr = host->phys_addr + SDDATA; 1300 1301 host->dma_cfg_rx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1302 host->dma_cfg_rx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 1303 host->dma_cfg_rx.slave_id = 13; /* DREQ channel */ 1304 host->dma_cfg_rx.direction = DMA_DEV_TO_MEM; 1305 host->dma_cfg_rx.src_addr = host->phys_addr + SDDATA; 1306 host->dma_cfg_rx.dst_addr = 0; 1307 1308 if (dmaengine_slave_config(host->dma_chan_rxtx, 1309 &host->dma_cfg_tx) != 0 || 1310 dmaengine_slave_config(host->dma_chan_rxtx, 1311 &host->dma_cfg_rx) != 0) 1312 host->use_dma = false; 1313 } 1314 1315 mmc->max_segs = 128; 1316 mmc->max_req_size = min_t(size_t, 524288, dma_max_mapping_size(dev)); 1317 mmc->max_seg_size = mmc->max_req_size; 1318 mmc->max_blk_size = 1024; 1319 mmc->max_blk_count = 65535; 1320 1321 /* report supported voltage ranges */ 1322 mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34; 1323 1324 INIT_WORK(&host->dma_work, bcm2835_dma_complete_work); 1325 INIT_DELAYED_WORK(&host->timeout_work, bcm2835_timeout); 1326 1327 /* Set interrupt enables */ 1328 host->hcfg = SDHCFG_BUSY_IRPT_EN; 1329 1330 bcm2835_reset_internal(host); 1331 1332 ret = request_threaded_irq(host->irq, bcm2835_irq, 1333 bcm2835_threaded_irq, 1334 0, mmc_hostname(mmc), host); 1335 if (ret) { 1336 dev_err(dev, "failed to request IRQ %d: %d\n", host->irq, ret); 1337 return ret; 1338 } 1339 1340 ret = mmc_add_host(mmc); 1341 if (ret) { 1342 free_irq(host->irq, host); 1343 return ret; 1344 } 1345 1346 pio_limit_string[0] = '\0'; 1347 if (host->use_dma && (PIO_THRESHOLD > 0)) 1348 sprintf(pio_limit_string, " (>%d)", PIO_THRESHOLD); 1349 dev_info(dev, "loaded - DMA %s%s\n", 1350 host->use_dma ? "enabled" : "disabled", pio_limit_string); 1351 1352 return 0; 1353 } 1354 1355 static int bcm2835_probe(struct platform_device *pdev) 1356 { 1357 struct device *dev = &pdev->dev; 1358 struct clk *clk; 1359 struct bcm2835_host *host; 1360 struct mmc_host *mmc; 1361 const __be32 *regaddr_p; 1362 int ret; 1363 1364 dev_dbg(dev, "%s\n", __func__); 1365 mmc = mmc_alloc_host(sizeof(*host), dev); 1366 if (!mmc) 1367 return -ENOMEM; 1368 1369 mmc->ops = &bcm2835_ops; 1370 host = mmc_priv(mmc); 1371 host->pdev = pdev; 1372 spin_lock_init(&host->lock); 1373 1374 host->ioaddr = devm_platform_ioremap_resource(pdev, 0); 1375 if (IS_ERR(host->ioaddr)) { 1376 ret = PTR_ERR(host->ioaddr); 1377 goto err; 1378 } 1379 1380 /* Parse OF address directly to get the physical address for 1381 * DMA to our registers. 1382 */ 1383 regaddr_p = of_get_address(pdev->dev.of_node, 0, NULL, NULL); 1384 if (!regaddr_p) { 1385 dev_err(dev, "Can't get phys address\n"); 1386 ret = -EINVAL; 1387 goto err; 1388 } 1389 1390 host->phys_addr = be32_to_cpup(regaddr_p); 1391 1392 host->dma_chan = NULL; 1393 host->dma_desc = NULL; 1394 1395 host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx"); 1396 if (IS_ERR(host->dma_chan_rxtx)) { 1397 ret = PTR_ERR(host->dma_chan_rxtx); 1398 host->dma_chan_rxtx = NULL; 1399 1400 if (ret == -EPROBE_DEFER) 1401 goto err; 1402 1403 /* Ignore errors to fall back to PIO mode */ 1404 } 1405 1406 1407 clk = devm_clk_get(dev, NULL); 1408 if (IS_ERR(clk)) { 1409 ret = dev_err_probe(dev, PTR_ERR(clk), "could not get clk\n"); 1410 goto err; 1411 } 1412 1413 host->max_clk = clk_get_rate(clk); 1414 1415 host->irq = platform_get_irq(pdev, 0); 1416 if (host->irq <= 0) { 1417 ret = -EINVAL; 1418 goto err; 1419 } 1420 1421 ret = mmc_of_parse(mmc); 1422 if (ret) 1423 goto err; 1424 1425 ret = bcm2835_add_host(host); 1426 if (ret) 1427 goto err; 1428 1429 platform_set_drvdata(pdev, host); 1430 1431 dev_dbg(dev, "%s -> OK\n", __func__); 1432 1433 return 0; 1434 1435 err: 1436 dev_dbg(dev, "%s -> err %d\n", __func__, ret); 1437 if (host->dma_chan_rxtx) 1438 dma_release_channel(host->dma_chan_rxtx); 1439 mmc_free_host(mmc); 1440 1441 return ret; 1442 } 1443 1444 static int bcm2835_remove(struct platform_device *pdev) 1445 { 1446 struct bcm2835_host *host = platform_get_drvdata(pdev); 1447 struct mmc_host *mmc = mmc_from_priv(host); 1448 1449 mmc_remove_host(mmc); 1450 1451 writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD); 1452 1453 free_irq(host->irq, host); 1454 1455 cancel_work_sync(&host->dma_work); 1456 cancel_delayed_work_sync(&host->timeout_work); 1457 1458 if (host->dma_chan_rxtx) 1459 dma_release_channel(host->dma_chan_rxtx); 1460 1461 mmc_free_host(mmc); 1462 1463 return 0; 1464 } 1465 1466 static const struct of_device_id bcm2835_match[] = { 1467 { .compatible = "brcm,bcm2835-sdhost" }, 1468 { } 1469 }; 1470 MODULE_DEVICE_TABLE(of, bcm2835_match); 1471 1472 static struct platform_driver bcm2835_driver = { 1473 .probe = bcm2835_probe, 1474 .remove = bcm2835_remove, 1475 .driver = { 1476 .name = "sdhost-bcm2835", 1477 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1478 .of_match_table = bcm2835_match, 1479 }, 1480 }; 1481 module_platform_driver(bcm2835_driver); 1482 1483 MODULE_ALIAS("platform:sdhost-bcm2835"); 1484 MODULE_DESCRIPTION("BCM2835 SDHost driver"); 1485 MODULE_LICENSE("GPL v2"); 1486 MODULE_AUTHOR("Phil Elwell"); 1487