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 19 #include "core.h" 20 #include "sysfs.h" 21 #include "mmc_ops.h" 22 #include "sd_ops.h" 23 24 #include "core.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("%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 BUG_ON(!mmc_card_sd(card)); 170 171 resp[3] = card->raw_scr[1]; 172 resp[2] = card->raw_scr[0]; 173 174 scr_struct = UNSTUFF_BITS(resp, 60, 4); 175 if (scr_struct != 0) { 176 printk("%s: unrecognised SCR structure version %d\n", 177 mmc_hostname(card->host), scr_struct); 178 return -EINVAL; 179 } 180 181 scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4); 182 scr->bus_widths = UNSTUFF_BITS(resp, 48, 4); 183 184 return 0; 185 } 186 187 /* 188 * Fetches and decodes switch information 189 */ 190 static int mmc_read_switch(struct mmc_card *card) 191 { 192 int err; 193 u8 *status; 194 195 err = MMC_ERR_FAILED; 196 197 status = kmalloc(64, GFP_KERNEL); 198 if (!status) { 199 printk("%s: could not allocate a buffer for switch " 200 "capabilities.\n", 201 mmc_hostname(card->host)); 202 return err; 203 } 204 205 err = mmc_sd_switch(card, 0, 0, 1, status); 206 if (err != MMC_ERR_NONE) { 207 /* 208 * Card not supporting high-speed will ignore the 209 * command. 210 */ 211 err = MMC_ERR_NONE; 212 goto out; 213 } 214 215 if (status[13] & 0x02) 216 card->sw_caps.hs_max_dtr = 50000000; 217 218 out: 219 kfree(status); 220 221 return err; 222 } 223 224 /* 225 * Test if the card supports high-speed mode and, if so, switch to it. 226 */ 227 static int mmc_switch_hs(struct mmc_card *card) 228 { 229 int err; 230 u8 *status; 231 232 if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED)) 233 return MMC_ERR_NONE; 234 235 if (card->sw_caps.hs_max_dtr == 0) 236 return MMC_ERR_NONE; 237 238 err = MMC_ERR_FAILED; 239 240 status = kmalloc(64, GFP_KERNEL); 241 if (!status) { 242 printk("%s: could not allocate a buffer for switch " 243 "capabilities.\n", 244 mmc_hostname(card->host)); 245 return err; 246 } 247 248 err = mmc_sd_switch(card, 1, 0, 1, status); 249 if (err != MMC_ERR_NONE) 250 goto out; 251 252 if ((status[16] & 0xF) != 1) { 253 printk(KERN_WARNING "%s: Problem switching card " 254 "into high-speed mode!\n", 255 mmc_hostname(card->host)); 256 } else { 257 mmc_card_set_highspeed(card); 258 mmc_set_timing(card->host, MMC_TIMING_SD_HS); 259 } 260 261 out: 262 kfree(status); 263 264 return err; 265 } 266 267 /* 268 * Handle the detection and initialisation of a card. 269 * 270 * In the case of a resume, "curcard" will contain the card 271 * we're trying to reinitialise. 272 */ 273 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, 274 struct mmc_card *oldcard) 275 { 276 struct mmc_card *card; 277 int err; 278 u32 cid[4]; 279 unsigned int max_dtr; 280 281 BUG_ON(!host); 282 BUG_ON(!host->claimed); 283 284 /* 285 * Since we're changing the OCR value, we seem to 286 * need to tell some cards to go back to the idle 287 * state. We wait 1ms to give cards time to 288 * respond. 289 */ 290 mmc_go_idle(host); 291 292 /* 293 * If SD_SEND_IF_COND indicates an SD 2.0 294 * compliant card and we should set bit 30 295 * of the ocr to indicate that we can handle 296 * block-addressed SDHC cards. 297 */ 298 err = mmc_send_if_cond(host, ocr); 299 if (err == MMC_ERR_NONE) 300 ocr |= 1 << 30; 301 302 err = mmc_send_app_op_cond(host, ocr, NULL); 303 if (err != MMC_ERR_NONE) 304 goto err; 305 306 /* 307 * Fetch CID from card. 308 */ 309 err = mmc_all_send_cid(host, cid); 310 if (err != MMC_ERR_NONE) 311 goto err; 312 313 if (oldcard) { 314 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) 315 goto err; 316 317 card = oldcard; 318 } else { 319 /* 320 * Allocate card structure. 321 */ 322 card = mmc_alloc_card(host); 323 if (IS_ERR(card)) 324 goto err; 325 326 card->type = MMC_TYPE_SD; 327 memcpy(card->raw_cid, cid, sizeof(card->raw_cid)); 328 } 329 330 /* 331 * Set card RCA. 332 */ 333 err = mmc_send_relative_addr(host, &card->rca); 334 if (err != MMC_ERR_NONE) 335 goto free_card; 336 337 mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); 338 339 if (!oldcard) { 340 /* 341 * Fetch CSD from card. 342 */ 343 err = mmc_send_csd(card, card->raw_csd); 344 if (err != MMC_ERR_NONE) 345 goto free_card; 346 347 err = mmc_decode_csd(card); 348 if (err < 0) 349 goto free_card; 350 351 mmc_decode_cid(card); 352 } 353 354 /* 355 * Select card, as all following commands rely on that. 356 */ 357 err = mmc_select_card(card); 358 if (err != MMC_ERR_NONE) 359 goto free_card; 360 361 if (!oldcard) { 362 /* 363 * Fetch SCR from card. 364 */ 365 err = mmc_app_send_scr(card, card->raw_scr); 366 if (err != MMC_ERR_NONE) 367 goto free_card; 368 369 err = mmc_decode_scr(card); 370 if (err < 0) 371 goto free_card; 372 373 /* 374 * Fetch switch information from card. 375 */ 376 err = mmc_read_switch(card); 377 if (err != MMC_ERR_NONE) 378 goto free_card; 379 } 380 381 /* 382 * Attempt to change to high-speed (if supported) 383 */ 384 err = mmc_switch_hs(card); 385 if (err != MMC_ERR_NONE) 386 goto free_card; 387 388 /* 389 * Compute bus speed. 390 */ 391 max_dtr = (unsigned int)-1; 392 393 if (mmc_card_highspeed(card)) { 394 if (max_dtr > card->sw_caps.hs_max_dtr) 395 max_dtr = card->sw_caps.hs_max_dtr; 396 } else if (max_dtr > card->csd.max_dtr) { 397 max_dtr = card->csd.max_dtr; 398 } 399 400 mmc_set_clock(host, max_dtr); 401 402 /* 403 * Switch to wider bus (if supported). 404 */ 405 if ((host->caps && MMC_CAP_4_BIT_DATA) && 406 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) { 407 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4); 408 if (err != MMC_ERR_NONE) 409 goto free_card; 410 411 mmc_set_bus_width(host, MMC_BUS_WIDTH_4); 412 } 413 414 if (!oldcard) 415 host->card = card; 416 417 return MMC_ERR_NONE; 418 419 free_card: 420 if (!oldcard) 421 mmc_remove_card(card); 422 err: 423 424 return MMC_ERR_FAILED; 425 } 426 427 /* 428 * Host is being removed. Free up the current card. 429 */ 430 static void mmc_sd_remove(struct mmc_host *host) 431 { 432 BUG_ON(!host); 433 BUG_ON(!host->card); 434 435 mmc_remove_card(host->card); 436 host->card = NULL; 437 } 438 439 /* 440 * Card detection callback from host. 441 */ 442 static void mmc_sd_detect(struct mmc_host *host) 443 { 444 int err; 445 446 BUG_ON(!host); 447 BUG_ON(!host->card); 448 449 mmc_claim_host(host); 450 451 /* 452 * Just check if our card has been removed. 453 */ 454 err = mmc_send_status(host->card, NULL); 455 456 mmc_release_host(host); 457 458 if (err != MMC_ERR_NONE) { 459 mmc_remove_card(host->card); 460 host->card = NULL; 461 462 mmc_claim_host(host); 463 mmc_detach_bus(host); 464 mmc_release_host(host); 465 } 466 } 467 468 #ifdef CONFIG_MMC_UNSAFE_RESUME 469 470 /* 471 * Suspend callback from host. 472 */ 473 static void mmc_sd_suspend(struct mmc_host *host) 474 { 475 BUG_ON(!host); 476 BUG_ON(!host->card); 477 478 mmc_claim_host(host); 479 mmc_deselect_cards(host); 480 host->card->state &= ~MMC_STATE_HIGHSPEED; 481 mmc_release_host(host); 482 } 483 484 /* 485 * Resume callback from host. 486 * 487 * This function tries to determine if the same card is still present 488 * and, if so, restore all state to it. 489 */ 490 static void mmc_sd_resume(struct mmc_host *host) 491 { 492 int err; 493 494 BUG_ON(!host); 495 BUG_ON(!host->card); 496 497 mmc_claim_host(host); 498 499 err = mmc_sd_init_card(host, host->ocr, host->card); 500 if (err != MMC_ERR_NONE) { 501 mmc_remove_card(host->card); 502 host->card = NULL; 503 504 mmc_detach_bus(host); 505 } 506 507 mmc_release_host(host); 508 } 509 510 #else 511 512 #define mmc_sd_suspend NULL 513 #define mmc_sd_resume NULL 514 515 #endif 516 517 static const struct mmc_bus_ops mmc_sd_ops = { 518 .remove = mmc_sd_remove, 519 .detect = mmc_sd_detect, 520 .suspend = mmc_sd_suspend, 521 .resume = mmc_sd_resume, 522 }; 523 524 /* 525 * Starting point for SD card init. 526 */ 527 int mmc_attach_sd(struct mmc_host *host, u32 ocr) 528 { 529 int err; 530 531 BUG_ON(!host); 532 BUG_ON(!host->claimed); 533 534 mmc_attach_bus(host, &mmc_sd_ops); 535 536 /* 537 * Sanity check the voltages that the card claims to 538 * support. 539 */ 540 if (ocr & 0x7F) { 541 printk(KERN_WARNING "%s: card claims to support voltages " 542 "below the defined range. These will be ignored.\n", 543 mmc_hostname(host)); 544 ocr &= ~0x7F; 545 } 546 547 if (ocr & MMC_VDD_165_195) { 548 printk(KERN_WARNING "%s: SD card claims to support the " 549 "incompletely defined 'low voltage range'. This " 550 "will be ignored.\n", mmc_hostname(host)); 551 ocr &= ~MMC_VDD_165_195; 552 } 553 554 host->ocr = mmc_select_voltage(host, ocr); 555 556 /* 557 * Can we support the voltage(s) of the card(s)? 558 */ 559 if (!host->ocr) 560 goto err; 561 562 /* 563 * Detect and init the card. 564 */ 565 err = mmc_sd_init_card(host, host->ocr, NULL); 566 if (err != MMC_ERR_NONE) 567 goto err; 568 569 mmc_release_host(host); 570 571 err = mmc_register_card(host->card); 572 if (err) 573 goto reclaim_host; 574 575 return 0; 576 577 reclaim_host: 578 mmc_claim_host(host); 579 mmc_remove_card(host->card); 580 host->card = NULL; 581 err: 582 mmc_detach_bus(host); 583 mmc_release_host(host); 584 585 return 0; 586 } 587 588