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