1 /* 2 * linux/drivers/mmc/core/sd.c 3 * 4 * Copyright (C) 2003-2004 Russell King, All Rights Reserved. 5 * SD support Copyright (C) 2004 Ian Molton, All Rights Reserved. 6 * Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/err.h> 14 #include <linux/slab.h> 15 16 #include <linux/mmc/host.h> 17 #include <linux/mmc/card.h> 18 #include <linux/mmc/mmc.h> 19 #include <linux/mmc/sd.h> 20 21 #include "core.h" 22 #include "bus.h" 23 #include "mmc_ops.h" 24 #include "sd_ops.h" 25 26 static const unsigned int tran_exp[] = { 27 10000, 100000, 1000000, 10000000, 28 0, 0, 0, 0 29 }; 30 31 static const unsigned char tran_mant[] = { 32 0, 10, 12, 13, 15, 20, 25, 30, 33 35, 40, 45, 50, 55, 60, 70, 80, 34 }; 35 36 static const unsigned int tacc_exp[] = { 37 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 38 }; 39 40 static const unsigned int tacc_mant[] = { 41 0, 10, 12, 13, 15, 20, 25, 30, 42 35, 40, 45, 50, 55, 60, 70, 80, 43 }; 44 45 #define UNSTUFF_BITS(resp,start,size) \ 46 ({ \ 47 const int __size = size; \ 48 const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \ 49 const int __off = 3 - ((start) / 32); \ 50 const int __shft = (start) & 31; \ 51 u32 __res; \ 52 \ 53 __res = resp[__off] >> __shft; \ 54 if (__size + __shft > 32) \ 55 __res |= resp[__off-1] << ((32 - __shft) % 32); \ 56 __res & __mask; \ 57 }) 58 59 /* 60 * Given the decoded CSD structure, decode the raw CID to our CID structure. 61 */ 62 static void mmc_decode_cid(struct mmc_card *card) 63 { 64 u32 *resp = card->raw_cid; 65 66 memset(&card->cid, 0, sizeof(struct mmc_cid)); 67 68 /* 69 * SD doesn't currently have a version field so we will 70 * have to assume we can parse this. 71 */ 72 card->cid.manfid = UNSTUFF_BITS(resp, 120, 8); 73 card->cid.oemid = UNSTUFF_BITS(resp, 104, 16); 74 card->cid.prod_name[0] = UNSTUFF_BITS(resp, 96, 8); 75 card->cid.prod_name[1] = UNSTUFF_BITS(resp, 88, 8); 76 card->cid.prod_name[2] = UNSTUFF_BITS(resp, 80, 8); 77 card->cid.prod_name[3] = UNSTUFF_BITS(resp, 72, 8); 78 card->cid.prod_name[4] = UNSTUFF_BITS(resp, 64, 8); 79 card->cid.hwrev = UNSTUFF_BITS(resp, 60, 4); 80 card->cid.fwrev = UNSTUFF_BITS(resp, 56, 4); 81 card->cid.serial = UNSTUFF_BITS(resp, 24, 32); 82 card->cid.year = UNSTUFF_BITS(resp, 12, 8); 83 card->cid.month = UNSTUFF_BITS(resp, 8, 4); 84 85 card->cid.year += 2000; /* SD cards year offset */ 86 } 87 88 /* 89 * Given a 128-bit response, decode to our card CSD structure. 90 */ 91 static int mmc_decode_csd(struct mmc_card *card) 92 { 93 struct mmc_csd *csd = &card->csd; 94 unsigned int e, m, csd_struct; 95 u32 *resp = card->raw_csd; 96 97 csd_struct = UNSTUFF_BITS(resp, 126, 2); 98 99 switch (csd_struct) { 100 case 0: 101 m = UNSTUFF_BITS(resp, 115, 4); 102 e = UNSTUFF_BITS(resp, 112, 3); 103 csd->tacc_ns = (tacc_exp[e] * tacc_mant[m] + 9) / 10; 104 csd->tacc_clks = UNSTUFF_BITS(resp, 104, 8) * 100; 105 106 m = UNSTUFF_BITS(resp, 99, 4); 107 e = UNSTUFF_BITS(resp, 96, 3); 108 csd->max_dtr = tran_exp[e] * tran_mant[m]; 109 csd->cmdclass = UNSTUFF_BITS(resp, 84, 12); 110 111 e = UNSTUFF_BITS(resp, 47, 3); 112 m = UNSTUFF_BITS(resp, 62, 12); 113 csd->capacity = (1 + m) << (e + 2); 114 115 csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4); 116 csd->read_partial = UNSTUFF_BITS(resp, 79, 1); 117 csd->write_misalign = UNSTUFF_BITS(resp, 78, 1); 118 csd->read_misalign = UNSTUFF_BITS(resp, 77, 1); 119 csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3); 120 csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4); 121 csd->write_partial = UNSTUFF_BITS(resp, 21, 1); 122 break; 123 case 1: 124 /* 125 * This is a block-addressed SDHC card. Most 126 * interesting fields are unused and have fixed 127 * values. To avoid getting tripped by buggy cards, 128 * we assume those fixed values ourselves. 129 */ 130 mmc_card_set_blockaddr(card); 131 132 csd->tacc_ns = 0; /* Unused */ 133 csd->tacc_clks = 0; /* Unused */ 134 135 m = UNSTUFF_BITS(resp, 99, 4); 136 e = UNSTUFF_BITS(resp, 96, 3); 137 csd->max_dtr = tran_exp[e] * tran_mant[m]; 138 csd->cmdclass = UNSTUFF_BITS(resp, 84, 12); 139 140 m = UNSTUFF_BITS(resp, 48, 22); 141 csd->capacity = (1 + m) << 10; 142 143 csd->read_blkbits = 9; 144 csd->read_partial = 0; 145 csd->write_misalign = 0; 146 csd->read_misalign = 0; 147 csd->r2w_factor = 4; /* Unused */ 148 csd->write_blkbits = 9; 149 csd->write_partial = 0; 150 break; 151 default: 152 printk(KERN_ERR "%s: unrecognised CSD structure version %d\n", 153 mmc_hostname(card->host), csd_struct); 154 return -EINVAL; 155 } 156 157 return 0; 158 } 159 160 /* 161 * Given a 64-bit response, decode to our card SCR structure. 162 */ 163 static int mmc_decode_scr(struct mmc_card *card) 164 { 165 struct sd_scr *scr = &card->scr; 166 unsigned int scr_struct; 167 u32 resp[4]; 168 169 resp[3] = card->raw_scr[1]; 170 resp[2] = card->raw_scr[0]; 171 172 scr_struct = UNSTUFF_BITS(resp, 60, 4); 173 if (scr_struct != 0) { 174 printk(KERN_ERR "%s: unrecognised SCR structure version %d\n", 175 mmc_hostname(card->host), scr_struct); 176 return -EINVAL; 177 } 178 179 scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4); 180 scr->bus_widths = UNSTUFF_BITS(resp, 48, 4); 181 182 return 0; 183 } 184 185 /* 186 * Fetches and decodes switch information 187 */ 188 static int mmc_read_switch(struct mmc_card *card) 189 { 190 int err; 191 u8 *status; 192 193 if (card->scr.sda_vsn < SCR_SPEC_VER_1) 194 return 0; 195 196 if (!(card->csd.cmdclass & CCC_SWITCH)) { 197 printk(KERN_WARNING "%s: card lacks mandatory switch " 198 "function, performance might suffer.\n", 199 mmc_hostname(card->host)); 200 return 0; 201 } 202 203 err = -EIO; 204 205 status = kmalloc(64, GFP_KERNEL); 206 if (!status) { 207 printk(KERN_ERR "%s: could not allocate a buffer for " 208 "switch capabilities.\n", mmc_hostname(card->host)); 209 return -ENOMEM; 210 } 211 212 err = mmc_sd_switch(card, 0, 0, 1, status); 213 if (err) { 214 /* If the host or the card can't do the switch, 215 * fail more gracefully. */ 216 if ((err != -EINVAL) 217 && (err != -ENOSYS) 218 && (err != -EFAULT)) 219 goto out; 220 221 printk(KERN_WARNING "%s: problem reading switch " 222 "capabilities, performance might suffer.\n", 223 mmc_hostname(card->host)); 224 err = 0; 225 226 goto out; 227 } 228 229 if (status[13] & 0x02) 230 card->sw_caps.hs_max_dtr = 50000000; 231 232 out: 233 kfree(status); 234 235 return err; 236 } 237 238 /* 239 * Test if the card supports high-speed mode and, if so, switch to it. 240 */ 241 static int mmc_switch_hs(struct mmc_card *card) 242 { 243 int err; 244 u8 *status; 245 246 if (card->scr.sda_vsn < SCR_SPEC_VER_1) 247 return 0; 248 249 if (!(card->csd.cmdclass & CCC_SWITCH)) 250 return 0; 251 252 if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED)) 253 return 0; 254 255 if (card->sw_caps.hs_max_dtr == 0) 256 return 0; 257 258 err = -EIO; 259 260 status = kmalloc(64, GFP_KERNEL); 261 if (!status) { 262 printk(KERN_ERR "%s: could not allocate a buffer for " 263 "switch capabilities.\n", mmc_hostname(card->host)); 264 return -ENOMEM; 265 } 266 267 err = mmc_sd_switch(card, 1, 0, 1, status); 268 if (err) 269 goto out; 270 271 if ((status[16] & 0xF) != 1) { 272 printk(KERN_WARNING "%s: Problem switching card " 273 "into high-speed mode!\n", 274 mmc_hostname(card->host)); 275 } else { 276 mmc_card_set_highspeed(card); 277 mmc_set_timing(card->host, MMC_TIMING_SD_HS); 278 } 279 280 out: 281 kfree(status); 282 283 return err; 284 } 285 286 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1], 287 card->raw_cid[2], card->raw_cid[3]); 288 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1], 289 card->raw_csd[2], card->raw_csd[3]); 290 MMC_DEV_ATTR(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]); 291 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year); 292 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev); 293 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev); 294 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid); 295 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name); 296 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid); 297 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial); 298 299 300 static struct attribute *sd_std_attrs[] = { 301 &dev_attr_cid.attr, 302 &dev_attr_csd.attr, 303 &dev_attr_scr.attr, 304 &dev_attr_date.attr, 305 &dev_attr_fwrev.attr, 306 &dev_attr_hwrev.attr, 307 &dev_attr_manfid.attr, 308 &dev_attr_name.attr, 309 &dev_attr_oemid.attr, 310 &dev_attr_serial.attr, 311 NULL, 312 }; 313 314 static struct attribute_group sd_std_attr_group = { 315 .attrs = sd_std_attrs, 316 }; 317 318 static const struct attribute_group *sd_attr_groups[] = { 319 &sd_std_attr_group, 320 NULL, 321 }; 322 323 static struct device_type sd_type = { 324 .groups = sd_attr_groups, 325 }; 326 327 /* 328 * Handle the detection and initialisation of a card. 329 * 330 * In the case of a resume, "oldcard" will contain the card 331 * we're trying to reinitialise. 332 */ 333 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, 334 struct mmc_card *oldcard) 335 { 336 struct mmc_card *card; 337 int err; 338 u32 cid[4]; 339 unsigned int max_dtr; 340 341 BUG_ON(!host); 342 WARN_ON(!host->claimed); 343 344 /* 345 * Since we're changing the OCR value, we seem to 346 * need to tell some cards to go back to the idle 347 * state. We wait 1ms to give cards time to 348 * respond. 349 */ 350 mmc_go_idle(host); 351 352 /* 353 * If SD_SEND_IF_COND indicates an SD 2.0 354 * compliant card and we should set bit 30 355 * of the ocr to indicate that we can handle 356 * block-addressed SDHC cards. 357 */ 358 err = mmc_send_if_cond(host, ocr); 359 if (!err) 360 ocr |= 1 << 30; 361 362 err = mmc_send_app_op_cond(host, ocr, NULL); 363 if (err) 364 goto err; 365 366 /* 367 * Fetch CID from card. 368 */ 369 if (mmc_host_is_spi(host)) 370 err = mmc_send_cid(host, cid); 371 else 372 err = mmc_all_send_cid(host, cid); 373 if (err) 374 goto err; 375 376 if (oldcard) { 377 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) { 378 err = -ENOENT; 379 goto err; 380 } 381 382 card = oldcard; 383 } else { 384 /* 385 * Allocate card structure. 386 */ 387 card = mmc_alloc_card(host, &sd_type); 388 if (IS_ERR(card)) { 389 err = PTR_ERR(card); 390 goto err; 391 } 392 393 card->type = MMC_TYPE_SD; 394 memcpy(card->raw_cid, cid, sizeof(card->raw_cid)); 395 } 396 397 /* 398 * For native busses: get card RCA and quit open drain mode. 399 */ 400 if (!mmc_host_is_spi(host)) { 401 err = mmc_send_relative_addr(host, &card->rca); 402 if (err) 403 goto free_card; 404 405 mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); 406 } 407 408 if (!oldcard) { 409 /* 410 * Fetch CSD from card. 411 */ 412 err = mmc_send_csd(card, card->raw_csd); 413 if (err) 414 goto free_card; 415 416 err = mmc_decode_csd(card); 417 if (err) 418 goto free_card; 419 420 mmc_decode_cid(card); 421 } 422 423 /* 424 * Select card, as all following commands rely on that. 425 */ 426 if (!mmc_host_is_spi(host)) { 427 err = mmc_select_card(card); 428 if (err) 429 goto free_card; 430 } 431 432 if (!oldcard) { 433 /* 434 * Fetch SCR from card. 435 */ 436 err = mmc_app_send_scr(card, card->raw_scr); 437 if (err) 438 goto free_card; 439 440 err = mmc_decode_scr(card); 441 if (err < 0) 442 goto free_card; 443 444 /* 445 * Fetch switch information from card. 446 */ 447 err = mmc_read_switch(card); 448 if (err) 449 goto free_card; 450 } 451 452 /* 453 * For SPI, enable CRC as appropriate. 454 * This CRC enable is located AFTER the reading of the 455 * card registers because some SDHC cards are not able 456 * to provide valid CRCs for non-512-byte blocks. 457 */ 458 if (mmc_host_is_spi(host)) { 459 err = mmc_spi_set_crc(host, use_spi_crc); 460 if (err) 461 goto free_card; 462 } 463 464 /* 465 * Attempt to change to high-speed (if supported) 466 */ 467 err = mmc_switch_hs(card); 468 if (err) 469 goto free_card; 470 471 /* 472 * Compute bus speed. 473 */ 474 max_dtr = (unsigned int)-1; 475 476 if (mmc_card_highspeed(card)) { 477 if (max_dtr > card->sw_caps.hs_max_dtr) 478 max_dtr = card->sw_caps.hs_max_dtr; 479 } else if (max_dtr > card->csd.max_dtr) { 480 max_dtr = card->csd.max_dtr; 481 } 482 483 mmc_set_clock(host, max_dtr); 484 485 /* 486 * Switch to wider bus (if supported). 487 */ 488 if ((host->caps & MMC_CAP_4_BIT_DATA) && 489 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) { 490 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4); 491 if (err) 492 goto free_card; 493 494 mmc_set_bus_width(host, MMC_BUS_WIDTH_4); 495 } 496 497 /* 498 * Check if read-only switch is active. 499 */ 500 if (!oldcard) { 501 if (!host->ops->get_ro || host->ops->get_ro(host) < 0) { 502 printk(KERN_WARNING "%s: host does not " 503 "support reading read-only " 504 "switch. assuming write-enable.\n", 505 mmc_hostname(host)); 506 } else { 507 if (host->ops->get_ro(host) > 0) 508 mmc_card_set_readonly(card); 509 } 510 } 511 512 if (!oldcard) 513 host->card = card; 514 515 return 0; 516 517 free_card: 518 if (!oldcard) 519 mmc_remove_card(card); 520 err: 521 522 return err; 523 } 524 525 /* 526 * Host is being removed. Free up the current card. 527 */ 528 static void mmc_sd_remove(struct mmc_host *host) 529 { 530 BUG_ON(!host); 531 BUG_ON(!host->card); 532 533 mmc_remove_card(host->card); 534 host->card = NULL; 535 } 536 537 /* 538 * Card detection callback from host. 539 */ 540 static void mmc_sd_detect(struct mmc_host *host) 541 { 542 int err; 543 544 BUG_ON(!host); 545 BUG_ON(!host->card); 546 547 mmc_claim_host(host); 548 549 /* 550 * Just check if our card has been removed. 551 */ 552 err = mmc_send_status(host->card, NULL); 553 554 mmc_release_host(host); 555 556 if (err) { 557 mmc_sd_remove(host); 558 559 mmc_claim_host(host); 560 mmc_detach_bus(host); 561 mmc_release_host(host); 562 } 563 } 564 565 /* 566 * Suspend callback from host. 567 */ 568 static int mmc_sd_suspend(struct mmc_host *host) 569 { 570 BUG_ON(!host); 571 BUG_ON(!host->card); 572 573 mmc_claim_host(host); 574 if (!mmc_host_is_spi(host)) 575 mmc_deselect_cards(host); 576 host->card->state &= ~MMC_STATE_HIGHSPEED; 577 mmc_release_host(host); 578 579 return 0; 580 } 581 582 /* 583 * Resume callback from host. 584 * 585 * This function tries to determine if the same card is still present 586 * and, if so, restore all state to it. 587 */ 588 static int mmc_sd_resume(struct mmc_host *host) 589 { 590 int err; 591 592 BUG_ON(!host); 593 BUG_ON(!host->card); 594 595 mmc_claim_host(host); 596 err = mmc_sd_init_card(host, host->ocr, host->card); 597 mmc_release_host(host); 598 599 return err; 600 } 601 602 static void mmc_sd_power_restore(struct mmc_host *host) 603 { 604 host->card->state &= ~MMC_STATE_HIGHSPEED; 605 mmc_claim_host(host); 606 mmc_sd_init_card(host, host->ocr, host->card); 607 mmc_release_host(host); 608 } 609 610 static const struct mmc_bus_ops mmc_sd_ops = { 611 .remove = mmc_sd_remove, 612 .detect = mmc_sd_detect, 613 .suspend = NULL, 614 .resume = NULL, 615 .power_restore = mmc_sd_power_restore, 616 }; 617 618 static const struct mmc_bus_ops mmc_sd_ops_unsafe = { 619 .remove = mmc_sd_remove, 620 .detect = mmc_sd_detect, 621 .suspend = mmc_sd_suspend, 622 .resume = mmc_sd_resume, 623 .power_restore = mmc_sd_power_restore, 624 }; 625 626 static void mmc_sd_attach_bus_ops(struct mmc_host *host) 627 { 628 const struct mmc_bus_ops *bus_ops; 629 630 if (host->caps & MMC_CAP_NONREMOVABLE || !mmc_assume_removable) 631 bus_ops = &mmc_sd_ops_unsafe; 632 else 633 bus_ops = &mmc_sd_ops; 634 mmc_attach_bus(host, bus_ops); 635 } 636 637 /* 638 * Starting point for SD card init. 639 */ 640 int mmc_attach_sd(struct mmc_host *host, u32 ocr) 641 { 642 int err; 643 644 BUG_ON(!host); 645 WARN_ON(!host->claimed); 646 647 mmc_sd_attach_bus_ops(host); 648 649 /* 650 * We need to get OCR a different way for SPI. 651 */ 652 if (mmc_host_is_spi(host)) { 653 mmc_go_idle(host); 654 655 err = mmc_spi_read_ocr(host, 0, &ocr); 656 if (err) 657 goto err; 658 } 659 660 /* 661 * Sanity check the voltages that the card claims to 662 * support. 663 */ 664 if (ocr & 0x7F) { 665 printk(KERN_WARNING "%s: card claims to support voltages " 666 "below the defined range. These will be ignored.\n", 667 mmc_hostname(host)); 668 ocr &= ~0x7F; 669 } 670 671 if (ocr & MMC_VDD_165_195) { 672 printk(KERN_WARNING "%s: SD card claims to support the " 673 "incompletely defined 'low voltage range'. This " 674 "will be ignored.\n", mmc_hostname(host)); 675 ocr &= ~MMC_VDD_165_195; 676 } 677 678 host->ocr = mmc_select_voltage(host, ocr); 679 680 /* 681 * Can we support the voltage(s) of the card(s)? 682 */ 683 if (!host->ocr) { 684 err = -EINVAL; 685 goto err; 686 } 687 688 /* 689 * Detect and init the card. 690 */ 691 err = mmc_sd_init_card(host, host->ocr, NULL); 692 if (err) 693 goto err; 694 695 mmc_release_host(host); 696 697 err = mmc_add_card(host->card); 698 if (err) 699 goto remove_card; 700 701 return 0; 702 703 remove_card: 704 mmc_remove_card(host->card); 705 host->card = NULL; 706 mmc_claim_host(host); 707 err: 708 mmc_detach_bus(host); 709 mmc_release_host(host); 710 711 printk(KERN_ERR "%s: error %d whilst initialising SD card\n", 712 mmc_hostname(host), err); 713 714 return err; 715 } 716 717