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 15 #include <linux/mmc/host.h> 16 #include <linux/mmc/card.h> 17 #include <linux/mmc/mmc.h> 18 #include <linux/mmc/sd.h> 19 20 #include "core.h" 21 #include "sysfs.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 /* 215 * We all hosts that cannot perform the command 216 * to fail more gracefully 217 */ 218 if (err != -EINVAL) 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 /* 287 * Handle the detection and initialisation of a card. 288 * 289 * In the case of a resume, "curcard" will contain the card 290 * we're trying to reinitialise. 291 */ 292 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, 293 struct mmc_card *oldcard) 294 { 295 struct mmc_card *card; 296 int err; 297 u32 cid[4]; 298 unsigned int max_dtr; 299 300 BUG_ON(!host); 301 WARN_ON(!host->claimed); 302 303 /* 304 * Since we're changing the OCR value, we seem to 305 * need to tell some cards to go back to the idle 306 * state. We wait 1ms to give cards time to 307 * respond. 308 */ 309 mmc_go_idle(host); 310 311 /* 312 * If SD_SEND_IF_COND indicates an SD 2.0 313 * compliant card and we should set bit 30 314 * of the ocr to indicate that we can handle 315 * block-addressed SDHC cards. 316 */ 317 err = mmc_send_if_cond(host, ocr); 318 if (!err) 319 ocr |= 1 << 30; 320 321 err = mmc_send_app_op_cond(host, ocr, NULL); 322 if (err) 323 goto err; 324 325 /* 326 * For SPI, enable CRC as appropriate. 327 */ 328 if (mmc_host_is_spi(host)) { 329 err = mmc_spi_set_crc(host, use_spi_crc); 330 if (err) 331 goto err; 332 } 333 334 /* 335 * Fetch CID from card. 336 */ 337 if (mmc_host_is_spi(host)) 338 err = mmc_send_cid(host, cid); 339 else 340 err = mmc_all_send_cid(host, cid); 341 if (err) 342 goto err; 343 344 if (oldcard) { 345 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) { 346 err = -ENOENT; 347 goto err; 348 } 349 350 card = oldcard; 351 } else { 352 /* 353 * Allocate card structure. 354 */ 355 card = mmc_alloc_card(host); 356 if (IS_ERR(card)) { 357 err = PTR_ERR(card); 358 goto err; 359 } 360 361 card->type = MMC_TYPE_SD; 362 memcpy(card->raw_cid, cid, sizeof(card->raw_cid)); 363 } 364 365 /* 366 * For native busses: get card RCA and quit open drain mode. 367 */ 368 if (!mmc_host_is_spi(host)) { 369 err = mmc_send_relative_addr(host, &card->rca); 370 if (err) 371 goto free_card; 372 373 mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); 374 } 375 376 if (!oldcard) { 377 /* 378 * Fetch CSD from card. 379 */ 380 err = mmc_send_csd(card, card->raw_csd); 381 if (err) 382 goto free_card; 383 384 err = mmc_decode_csd(card); 385 if (err) 386 goto free_card; 387 388 mmc_decode_cid(card); 389 } 390 391 /* 392 * Select card, as all following commands rely on that. 393 */ 394 if (!mmc_host_is_spi(host)) { 395 err = mmc_select_card(card); 396 if (err) 397 goto free_card; 398 } 399 400 if (!oldcard) { 401 /* 402 * Fetch SCR from card. 403 */ 404 err = mmc_app_send_scr(card, card->raw_scr); 405 if (err) 406 goto free_card; 407 408 err = mmc_decode_scr(card); 409 if (err < 0) 410 goto free_card; 411 412 /* 413 * Fetch switch information from card. 414 */ 415 err = mmc_read_switch(card); 416 if (err) 417 goto free_card; 418 } 419 420 /* 421 * Attempt to change to high-speed (if supported) 422 */ 423 err = mmc_switch_hs(card); 424 if (err) 425 goto free_card; 426 427 /* 428 * Compute bus speed. 429 */ 430 max_dtr = (unsigned int)-1; 431 432 if (mmc_card_highspeed(card)) { 433 if (max_dtr > card->sw_caps.hs_max_dtr) 434 max_dtr = card->sw_caps.hs_max_dtr; 435 } else if (max_dtr > card->csd.max_dtr) { 436 max_dtr = card->csd.max_dtr; 437 } 438 439 mmc_set_clock(host, max_dtr); 440 441 /* 442 * Switch to wider bus (if supported). 443 */ 444 if ((host->caps & MMC_CAP_4_BIT_DATA) && 445 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) { 446 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4); 447 if (err) 448 goto free_card; 449 450 mmc_set_bus_width(host, MMC_BUS_WIDTH_4); 451 } 452 453 /* 454 * Check if read-only switch is active. 455 */ 456 if (!oldcard) { 457 if (!host->ops->get_ro) { 458 printk(KERN_WARNING "%s: host does not " 459 "support reading read-only " 460 "switch. assuming write-enable.\n", 461 mmc_hostname(host)); 462 } else { 463 if (host->ops->get_ro(host)) 464 mmc_card_set_readonly(card); 465 } 466 } 467 468 if (!oldcard) 469 host->card = card; 470 471 return 0; 472 473 free_card: 474 if (!oldcard) 475 mmc_remove_card(card); 476 err: 477 478 return err; 479 } 480 481 /* 482 * Host is being removed. Free up the current card. 483 */ 484 static void mmc_sd_remove(struct mmc_host *host) 485 { 486 BUG_ON(!host); 487 BUG_ON(!host->card); 488 489 mmc_remove_card(host->card); 490 host->card = NULL; 491 } 492 493 /* 494 * Card detection callback from host. 495 */ 496 static void mmc_sd_detect(struct mmc_host *host) 497 { 498 int err; 499 500 BUG_ON(!host); 501 BUG_ON(!host->card); 502 503 mmc_claim_host(host); 504 505 /* 506 * Just check if our card has been removed. 507 */ 508 err = mmc_send_status(host->card, NULL); 509 510 mmc_release_host(host); 511 512 if (err) { 513 mmc_sd_remove(host); 514 515 mmc_claim_host(host); 516 mmc_detach_bus(host); 517 mmc_release_host(host); 518 } 519 } 520 521 MMC_ATTR_FN(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1], 522 card->raw_cid[2], card->raw_cid[3]); 523 MMC_ATTR_FN(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1], 524 card->raw_csd[2], card->raw_csd[3]); 525 MMC_ATTR_FN(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]); 526 MMC_ATTR_FN(date, "%02d/%04d\n", card->cid.month, card->cid.year); 527 MMC_ATTR_FN(fwrev, "0x%x\n", card->cid.fwrev); 528 MMC_ATTR_FN(hwrev, "0x%x\n", card->cid.hwrev); 529 MMC_ATTR_FN(manfid, "0x%06x\n", card->cid.manfid); 530 MMC_ATTR_FN(name, "%s\n", card->cid.prod_name); 531 MMC_ATTR_FN(oemid, "0x%04x\n", card->cid.oemid); 532 MMC_ATTR_FN(serial, "0x%08x\n", card->cid.serial); 533 534 static struct device_attribute mmc_sd_dev_attrs[] = { 535 MMC_ATTR_RO(cid), 536 MMC_ATTR_RO(csd), 537 MMC_ATTR_RO(scr), 538 MMC_ATTR_RO(date), 539 MMC_ATTR_RO(fwrev), 540 MMC_ATTR_RO(hwrev), 541 MMC_ATTR_RO(manfid), 542 MMC_ATTR_RO(name), 543 MMC_ATTR_RO(oemid), 544 MMC_ATTR_RO(serial), 545 __ATTR_NULL, 546 }; 547 548 /* 549 * Adds sysfs entries as relevant. 550 */ 551 static int mmc_sd_sysfs_add(struct mmc_host *host, struct mmc_card *card) 552 { 553 int ret; 554 555 ret = mmc_add_attrs(card, mmc_sd_dev_attrs); 556 if (ret < 0) 557 return ret; 558 559 return 0; 560 } 561 562 /* 563 * Removes the sysfs entries added by mmc_sysfs_add(). 564 */ 565 static void mmc_sd_sysfs_remove(struct mmc_host *host, struct mmc_card *card) 566 { 567 mmc_remove_attrs(card, mmc_sd_dev_attrs); 568 } 569 570 #ifdef CONFIG_MMC_UNSAFE_RESUME 571 572 /* 573 * Suspend callback from host. 574 */ 575 static void mmc_sd_suspend(struct mmc_host *host) 576 { 577 BUG_ON(!host); 578 BUG_ON(!host->card); 579 580 mmc_claim_host(host); 581 if (!mmc_host_is_spi(host)) 582 mmc_deselect_cards(host); 583 host->card->state &= ~MMC_STATE_HIGHSPEED; 584 mmc_release_host(host); 585 } 586 587 /* 588 * Resume callback from host. 589 * 590 * This function tries to determine if the same card is still present 591 * and, if so, restore all state to it. 592 */ 593 static void mmc_sd_resume(struct mmc_host *host) 594 { 595 int err; 596 597 BUG_ON(!host); 598 BUG_ON(!host->card); 599 600 mmc_claim_host(host); 601 err = mmc_sd_init_card(host, host->ocr, host->card); 602 mmc_release_host(host); 603 604 if (err) { 605 mmc_sd_remove(host); 606 607 mmc_claim_host(host); 608 mmc_detach_bus(host); 609 mmc_release_host(host); 610 } 611 612 } 613 614 #else 615 616 #define mmc_sd_suspend NULL 617 #define mmc_sd_resume NULL 618 619 #endif 620 621 static const struct mmc_bus_ops mmc_sd_ops = { 622 .remove = mmc_sd_remove, 623 .detect = mmc_sd_detect, 624 .sysfs_add = mmc_sd_sysfs_add, 625 .sysfs_remove = mmc_sd_sysfs_remove, 626 .suspend = mmc_sd_suspend, 627 .resume = mmc_sd_resume, 628 }; 629 630 /* 631 * Starting point for SD card init. 632 */ 633 int mmc_attach_sd(struct mmc_host *host, u32 ocr) 634 { 635 int err; 636 637 BUG_ON(!host); 638 WARN_ON(!host->claimed); 639 640 mmc_attach_bus(host, &mmc_sd_ops); 641 642 /* 643 * We need to get OCR a different way for SPI. 644 */ 645 if (mmc_host_is_spi(host)) { 646 mmc_go_idle(host); 647 648 err = mmc_spi_read_ocr(host, 0, &ocr); 649 if (err) 650 goto err; 651 } 652 653 /* 654 * Sanity check the voltages that the card claims to 655 * support. 656 */ 657 if (ocr & 0x7F) { 658 printk(KERN_WARNING "%s: card claims to support voltages " 659 "below the defined range. These will be ignored.\n", 660 mmc_hostname(host)); 661 ocr &= ~0x7F; 662 } 663 664 if (ocr & MMC_VDD_165_195) { 665 printk(KERN_WARNING "%s: SD card claims to support the " 666 "incompletely defined 'low voltage range'. This " 667 "will be ignored.\n", mmc_hostname(host)); 668 ocr &= ~MMC_VDD_165_195; 669 } 670 671 host->ocr = mmc_select_voltage(host, ocr); 672 673 /* 674 * Can we support the voltage(s) of the card(s)? 675 */ 676 if (!host->ocr) { 677 err = -EINVAL; 678 goto err; 679 } 680 681 /* 682 * Detect and init the card. 683 */ 684 err = mmc_sd_init_card(host, host->ocr, NULL); 685 if (err) 686 goto err; 687 688 mmc_release_host(host); 689 690 err = mmc_add_card(host->card); 691 if (err) 692 goto remove_card; 693 694 return 0; 695 696 remove_card: 697 mmc_remove_card(host->card); 698 host->card = NULL; 699 mmc_claim_host(host); 700 err: 701 mmc_detach_bus(host); 702 mmc_release_host(host); 703 704 printk(KERN_ERR "%s: error %d whilst initialising SD card\n", 705 mmc_hostname(host), err); 706 707 return err; 708 } 709 710