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