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, "curcard" 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 * For SPI, enable CRC as appropriate. 367 */ 368 if (mmc_host_is_spi(host)) { 369 err = mmc_spi_set_crc(host, use_spi_crc); 370 if (err) 371 goto err; 372 } 373 374 /* 375 * Fetch CID from card. 376 */ 377 if (mmc_host_is_spi(host)) 378 err = mmc_send_cid(host, cid); 379 else 380 err = mmc_all_send_cid(host, cid); 381 if (err) 382 goto err; 383 384 if (oldcard) { 385 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) { 386 err = -ENOENT; 387 goto err; 388 } 389 390 card = oldcard; 391 } else { 392 /* 393 * Allocate card structure. 394 */ 395 card = mmc_alloc_card(host, &sd_type); 396 if (IS_ERR(card)) { 397 err = PTR_ERR(card); 398 goto err; 399 } 400 401 card->type = MMC_TYPE_SD; 402 memcpy(card->raw_cid, cid, sizeof(card->raw_cid)); 403 } 404 405 /* 406 * For native busses: get card RCA and quit open drain mode. 407 */ 408 if (!mmc_host_is_spi(host)) { 409 err = mmc_send_relative_addr(host, &card->rca); 410 if (err) 411 goto free_card; 412 413 mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); 414 } 415 416 if (!oldcard) { 417 /* 418 * Fetch CSD from card. 419 */ 420 err = mmc_send_csd(card, card->raw_csd); 421 if (err) 422 goto free_card; 423 424 err = mmc_decode_csd(card); 425 if (err) 426 goto free_card; 427 428 mmc_decode_cid(card); 429 } 430 431 /* 432 * Select card, as all following commands rely on that. 433 */ 434 if (!mmc_host_is_spi(host)) { 435 err = mmc_select_card(card); 436 if (err) 437 goto free_card; 438 } 439 440 if (!oldcard) { 441 /* 442 * Fetch SCR from card. 443 */ 444 err = mmc_app_send_scr(card, card->raw_scr); 445 if (err) 446 goto free_card; 447 448 err = mmc_decode_scr(card); 449 if (err < 0) 450 goto free_card; 451 452 /* 453 * Fetch switch information from card. 454 */ 455 err = mmc_read_switch(card); 456 if (err) 457 goto free_card; 458 } 459 460 /* 461 * Attempt to change to high-speed (if supported) 462 */ 463 err = mmc_switch_hs(card); 464 if (err) 465 goto free_card; 466 467 /* 468 * Compute bus speed. 469 */ 470 max_dtr = (unsigned int)-1; 471 472 if (mmc_card_highspeed(card)) { 473 if (max_dtr > card->sw_caps.hs_max_dtr) 474 max_dtr = card->sw_caps.hs_max_dtr; 475 } else if (max_dtr > card->csd.max_dtr) { 476 max_dtr = card->csd.max_dtr; 477 } 478 479 mmc_set_clock(host, max_dtr); 480 481 /* 482 * Switch to wider bus (if supported). 483 */ 484 if ((host->caps & MMC_CAP_4_BIT_DATA) && 485 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) { 486 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4); 487 if (err) 488 goto free_card; 489 490 mmc_set_bus_width(host, MMC_BUS_WIDTH_4); 491 } 492 493 /* 494 * Check if read-only switch is active. 495 */ 496 if (!oldcard) { 497 if (!host->ops->get_ro) { 498 printk(KERN_WARNING "%s: host does not " 499 "support reading read-only " 500 "switch. assuming write-enable.\n", 501 mmc_hostname(host)); 502 } else { 503 if (host->ops->get_ro(host)) 504 mmc_card_set_readonly(card); 505 } 506 } 507 508 if (!oldcard) 509 host->card = card; 510 511 return 0; 512 513 free_card: 514 if (!oldcard) 515 mmc_remove_card(card); 516 err: 517 518 return err; 519 } 520 521 /* 522 * Host is being removed. Free up the current card. 523 */ 524 static void mmc_sd_remove(struct mmc_host *host) 525 { 526 BUG_ON(!host); 527 BUG_ON(!host->card); 528 529 mmc_remove_card(host->card); 530 host->card = NULL; 531 } 532 533 /* 534 * Card detection callback from host. 535 */ 536 static void mmc_sd_detect(struct mmc_host *host) 537 { 538 int err; 539 540 BUG_ON(!host); 541 BUG_ON(!host->card); 542 543 mmc_claim_host(host); 544 545 /* 546 * Just check if our card has been removed. 547 */ 548 err = mmc_send_status(host->card, NULL); 549 550 mmc_release_host(host); 551 552 if (err) { 553 mmc_sd_remove(host); 554 555 mmc_claim_host(host); 556 mmc_detach_bus(host); 557 mmc_release_host(host); 558 } 559 } 560 561 #ifdef CONFIG_MMC_UNSAFE_RESUME 562 563 /* 564 * Suspend callback from host. 565 */ 566 static void mmc_sd_suspend(struct mmc_host *host) 567 { 568 BUG_ON(!host); 569 BUG_ON(!host->card); 570 571 mmc_claim_host(host); 572 if (!mmc_host_is_spi(host)) 573 mmc_deselect_cards(host); 574 host->card->state &= ~MMC_STATE_HIGHSPEED; 575 mmc_release_host(host); 576 } 577 578 /* 579 * Resume callback from host. 580 * 581 * This function tries to determine if the same card is still present 582 * and, if so, restore all state to it. 583 */ 584 static void mmc_sd_resume(struct mmc_host *host) 585 { 586 int err; 587 588 BUG_ON(!host); 589 BUG_ON(!host->card); 590 591 mmc_claim_host(host); 592 err = mmc_sd_init_card(host, host->ocr, host->card); 593 mmc_release_host(host); 594 595 if (err) { 596 mmc_sd_remove(host); 597 598 mmc_claim_host(host); 599 mmc_detach_bus(host); 600 mmc_release_host(host); 601 } 602 603 } 604 605 #else 606 607 #define mmc_sd_suspend NULL 608 #define mmc_sd_resume NULL 609 610 #endif 611 612 static const struct mmc_bus_ops mmc_sd_ops = { 613 .remove = mmc_sd_remove, 614 .detect = mmc_sd_detect, 615 .suspend = mmc_sd_suspend, 616 .resume = mmc_sd_resume, 617 }; 618 619 /* 620 * Starting point for SD card init. 621 */ 622 int mmc_attach_sd(struct mmc_host *host, u32 ocr) 623 { 624 int err; 625 626 BUG_ON(!host); 627 WARN_ON(!host->claimed); 628 629 mmc_attach_bus(host, &mmc_sd_ops); 630 631 /* 632 * We need to get OCR a different way for SPI. 633 */ 634 if (mmc_host_is_spi(host)) { 635 mmc_go_idle(host); 636 637 err = mmc_spi_read_ocr(host, 0, &ocr); 638 if (err) 639 goto err; 640 } 641 642 /* 643 * Sanity check the voltages that the card claims to 644 * support. 645 */ 646 if (ocr & 0x7F) { 647 printk(KERN_WARNING "%s: card claims to support voltages " 648 "below the defined range. These will be ignored.\n", 649 mmc_hostname(host)); 650 ocr &= ~0x7F; 651 } 652 653 if (ocr & MMC_VDD_165_195) { 654 printk(KERN_WARNING "%s: SD card claims to support the " 655 "incompletely defined 'low voltage range'. This " 656 "will be ignored.\n", mmc_hostname(host)); 657 ocr &= ~MMC_VDD_165_195; 658 } 659 660 host->ocr = mmc_select_voltage(host, ocr); 661 662 /* 663 * Can we support the voltage(s) of the card(s)? 664 */ 665 if (!host->ocr) { 666 err = -EINVAL; 667 goto err; 668 } 669 670 /* 671 * Detect and init the card. 672 */ 673 err = mmc_sd_init_card(host, host->ocr, NULL); 674 if (err) 675 goto err; 676 677 mmc_release_host(host); 678 679 err = mmc_add_card(host->card); 680 if (err) 681 goto remove_card; 682 683 return 0; 684 685 remove_card: 686 mmc_remove_card(host->card); 687 host->card = NULL; 688 mmc_claim_host(host); 689 err: 690 mmc_detach_bus(host); 691 mmc_release_host(host); 692 693 printk(KERN_ERR "%s: error %d whilst initialising SD card\n", 694 mmc_hostname(host), err); 695 696 return err; 697 } 698 699