altera_sdcard_io.c revision 245818
1/*- 2 * Copyright (c) 2012 Robert N. M. Watson 3 * All rights reserved. 4 * 5 * This software was developed by SRI International and the University of 6 * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237) 7 * ("CTSRD"), as part of the DARPA CRASH research programme. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31#include <sys/cdefs.h> 32__FBSDID("$FreeBSD: head/sys/dev/altera/sdcard/altera_sdcard_io.c 245818 2013-01-22 18:48:45Z brooks $"); 33 34#include <sys/param.h> 35#include <sys/bus.h> 36#include <sys/condvar.h> 37#include <sys/conf.h> 38#include <sys/bio.h> 39#include <sys/endian.h> 40#include <sys/kernel.h> 41#include <sys/lock.h> 42#include <sys/malloc.h> 43#include <sys/module.h> 44#include <sys/mutex.h> 45#include <sys/rman.h> 46#include <sys/systm.h> 47#include <sys/taskqueue.h> 48 49#include <machine/bus.h> 50#include <machine/resource.h> 51 52#include <geom/geom_disk.h> 53 54#include <dev/altera/sdcard/altera_sdcard.h> 55 56int altera_sdcard_ignore_crc_errors = 1; 57int altera_sdcard_verify_rxtx_writes = 1; 58 59/* 60 * Low-level I/O routines for the Altera SD Card University IP Core driver. 61 * 62 * XXXRW: Throughout, it is assumed that the IP Core handles multibyte 63 * registers as little endian, as is the case for other Altera IP cores. 64 * However, the specification makes no reference to endianness, so this 65 * assumption might not always be correct. 66 */ 67uint16_t 68altera_sdcard_read_asr(struct altera_sdcard_softc *sc) 69{ 70 71 return (le16toh(bus_read_2(sc->as_res, ALTERA_SDCARD_OFF_ASR))); 72} 73 74static int 75altera_sdcard_process_csd0(struct altera_sdcard_softc *sc) 76{ 77 uint64_t c_size, c_size_mult, read_bl_len; 78 uint8_t byte0, byte1, byte2; 79 80 ALTERA_SDCARD_LOCK_ASSERT(sc); 81 82 /*- 83 * Compute card capacity per SD Card interface description as follows: 84 * 85 * Memory capacity = BLOCKNR * BLOCK_LEN 86 * 87 * Where: 88 * 89 * BLOCKNR = (C_SIZE + 1) * MULT 90 * MULT = 2^(C_SIZE_MULT+2) 91 * BLOCK_LEN = 2^READ_BL_LEN 92 */ 93 read_bl_len = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_READ_BL_LEN_BYTE]; 94 read_bl_len &= ALTERA_SDCARD_CSD_READ_BL_LEN_MASK; 95 96 byte0 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_BYTE0]; 97 byte0 &= ALTERA_SDCARD_CSD_C_SIZE_MASK0; 98 byte1 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_BYTE1]; 99 byte2 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_BYTE2]; 100 byte2 &= ALTERA_SDCARD_CSD_C_SIZE_MASK2; 101 c_size = (byte0 >> ALTERA_SDCARD_CSD_C_SIZE_RSHIFT0) | 102 (byte1 << ALTERA_SDCARD_CSD_C_SIZE_LSHIFT1) | 103 (byte2 << ALTERA_SDCARD_CSD_C_SIZE_LSHIFT2); 104 105 byte0 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_MULT_BYTE0]; 106 byte0 &= ALTERA_SDCARD_CSD_C_SIZE_MULT_MASK0; 107 byte1 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_MULT_BYTE1]; 108 byte1 &= ALTERA_SDCARD_CSD_C_SIZE_MULT_MASK1; 109 c_size_mult = (byte0 >> ALTERA_SDCARD_CSD_C_SIZE_MULT_RSHIFT0) | 110 (byte1 << ALTERA_SDCARD_CSD_C_SIZE_MULT_LSHIFT1); 111 112 /* 113 * If we're just getting back zero's, mark the card as bad, even 114 * though it could just mean a Very Small Disk Indeed. 115 */ 116 if (c_size == 0 && c_size_mult == 0 && read_bl_len == 0) { 117 device_printf(sc->as_dev, "Ignored zero-size card\n"); 118 return (ENXIO); 119 } 120 sc->as_mediasize = (c_size + 1) * (1 << (c_size_mult + 2)) * 121 (1 << read_bl_len); 122 return (0); 123} 124 125int 126altera_sdcard_read_csd(struct altera_sdcard_softc *sc) 127{ 128 uint8_t csd_structure; 129 int error; 130 131 ALTERA_SDCARD_LOCK_ASSERT(sc); 132 133 /* 134 * XXXRW: Assume for now that when the SD Card IP Core negotiates 135 * voltage/speed/etc, it must use the CSD register, and therefore 136 * populates the SD Card IP Core's cache of the register value. This 137 * means that we can read it without issuing further SD Card commands. 138 * If this assumption proves false, we will (a) get back garbage and 139 * (b) need to add additional states in the driver state machine in 140 * order to query card properties before I/O can start. 141 * 142 * XXXRW: Treating this as an array of bytes, so no byte swapping -- 143 * is that a safe assumption? 144 */ 145 KASSERT(((uintptr_t)&sc->as_csd.csd_data) % 2 == 0, 146 ("%s: CSD buffer unaligned", __func__)); 147 bus_read_region_2(sc->as_res, ALTERA_SDCARD_OFF_CSD, 148 (uint16_t *)sc->as_csd.csd_data, sizeof(sc->as_csd) / 2); 149 150 /* 151 * Interpret the loaded CSD, extracting certain fields and copying 152 * them into the softc for easy software access. 153 * 154 * Currently, we support only CSD Version 1.0. If we detect a newer 155 * version, suppress card detection. 156 */ 157 csd_structure = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_STRUCTURE_BYTE]; 158 csd_structure &= ALTERA_SDCARD_CSD_STRUCTURE_MASK; 159 csd_structure >>= ALTERA_SDCARD_CSD_STRUCTURE_RSHIFT; 160 sc->as_csd_structure = csd_structure; 161 162 /* 163 * Interpret the CSD field based on its version. Extract fields, 164 * especially mediasize. 165 * 166 * XXXRW: Desirable to support further CSD versions here. 167 */ 168 switch (sc->as_csd_structure) { 169 case 0: 170 error = altera_sdcard_process_csd0(sc); 171 if (error) 172 return (error); 173 break; 174 175 default: 176 device_printf(sc->as_dev, 177 "Ignored disk with unsupported CSD structure (%d)\n", 178 sc->as_csd_structure); 179 return (ENXIO); 180 } 181 return (0); 182} 183 184/* 185 * XXXRW: The Altera IP Core specification indicates that RR1 is a 16-bit 186 * register, but all bits it identifies are >16 bit. Most likely, RR1 is a 187 * 32-bit register? 188 */ 189static uint16_t 190altera_sdcard_read_rr1(struct altera_sdcard_softc *sc) 191{ 192 193 return (le16toh(bus_read_2(sc->as_res, ALTERA_SDCARD_OFF_RR1))); 194} 195 196static void 197altera_sdcard_write_cmd_arg(struct altera_sdcard_softc *sc, uint32_t cmd_arg) 198{ 199 200 bus_write_4(sc->as_res, ALTERA_SDCARD_OFF_CMD_ARG, htole32(cmd_arg)); 201} 202 203static void 204altera_sdcard_write_cmd(struct altera_sdcard_softc *sc, uint16_t cmd) 205{ 206 207 bus_write_2(sc->as_res, ALTERA_SDCARD_OFF_CMD, htole16(cmd)); 208} 209 210static void 211altera_sdcard_read_rxtx_buffer(struct altera_sdcard_softc *sc, void *data, 212 size_t len) 213{ 214 215 KASSERT((uintptr_t)data % 2 == 0, 216 ("%s: unaligned data %p", __func__, data)); 217 KASSERT((len <= ALTERA_SDCARD_SECTORSIZE) && (len % 2 == 0), 218 ("%s: invalid length %ju", __func__, len)); 219 220 bus_read_region_2(sc->as_res, ALTERA_SDCARD_OFF_RXTX_BUFFER, 221 (uint16_t *)data, len / 2); 222} 223 224static void 225altera_sdcard_write_rxtx_buffer(struct altera_sdcard_softc *sc, void *data, 226 size_t len) 227{ 228 u_int corrections, differences, i, retry_counter; 229 uint16_t d, v; 230 231 KASSERT((uintptr_t)data % 2 == 0, 232 ("%s: unaligned data %p", __func__, data)); 233 KASSERT((len <= ALTERA_SDCARD_SECTORSIZE) && (len % 2 == 0), 234 ("%s: invalid length %ju", __func__, len)); 235 236 retry_counter = 0; 237 do { 238 bus_write_region_2(sc->as_res, ALTERA_SDCARD_OFF_RXTX_BUFFER, 239 (uint16_t *)data, len / 2); 240 241 /* 242 * XXXRW: Due to a possible hardware bug, the above call to 243 * bus_write_region_2() might not succeed. If the workaround 244 * is enabled, verify each write and retry until it succeeds. 245 * 246 * XXXRW: Do we want a limit counter for retries here? 247 */ 248recheck: 249 corrections = 0; 250 differences = 0; 251 if (altera_sdcard_verify_rxtx_writes) { 252 for (i = 0; i < ALTERA_SDCARD_SECTORSIZE; i += 2) { 253 v = bus_read_2(sc->as_res, 254 ALTERA_SDCARD_OFF_RXTX_BUFFER + i); 255 d = *(uint16_t *)((uint8_t *)data + i); 256 if (v != d) { 257 if (retry_counter == 0) { 258 bus_write_2(sc->as_res, 259 ALTERA_SDCARD_OFF_RXTX_BUFFER + i, 260 d); 261 v = bus_read_2(sc->as_res, 262 ALTERA_SDCARD_OFF_RXTX_BUFFER + i); 263 if (v == d) { 264 corrections++; 265 device_printf(sc->as_dev, 266 "%s: single word rewrite worked" 267 " at offset %u\n", 268 __func__, i); 269 continue; 270 } 271 } 272 differences++; 273 device_printf(sc->as_dev, 274 "%s: retrying write -- difference" 275 " %u at offset %u, retry %u\n", 276 __func__, differences, i, 277 retry_counter); 278 } 279 } 280 if (differences != 0) { 281 retry_counter++; 282 if (retry_counter == 1 && 283 corrections == differences) 284 goto recheck; 285 } 286 } 287 } while (differences != 0); 288 if (retry_counter) 289 device_printf(sc->as_dev, "%s: succeeded after %u retries\n", 290 __func__, retry_counter); 291} 292 293static void 294altera_sdcard_io_start_internal(struct altera_sdcard_softc *sc, struct bio *bp) 295{ 296 297 switch (bp->bio_cmd) { 298 case BIO_READ: 299 altera_sdcard_write_cmd_arg(sc, bp->bio_pblkno * 300 ALTERA_SDCARD_SECTORSIZE); 301 altera_sdcard_write_cmd(sc, ALTERA_SDCARD_CMD_READ_BLOCK); 302 break; 303 304 case BIO_WRITE: 305 altera_sdcard_write_rxtx_buffer(sc, bp->bio_data, 306 bp->bio_bcount); 307 altera_sdcard_write_cmd_arg(sc, bp->bio_pblkno * 308 ALTERA_SDCARD_SECTORSIZE); 309 altera_sdcard_write_cmd(sc, ALTERA_SDCARD_CMD_WRITE_BLOCK); 310 break; 311 312 default: 313 panic("%s: unsupported I/O operation %d", __func__, 314 bp->bio_cmd); 315 } 316} 317 318void 319altera_sdcard_io_start(struct altera_sdcard_softc *sc, struct bio *bp) 320{ 321 322 ALTERA_SDCARD_LOCK_ASSERT(sc); 323 KASSERT(sc->as_currentbio == NULL, 324 ("%s: bio already started", __func__)); 325 326 /* 327 * We advertise a block size and maximum I/O size up the stack of the 328 * SD Card IP Core sector size. Catch any attempts to not follow the 329 * rules. 330 */ 331 KASSERT(bp->bio_bcount == ALTERA_SDCARD_SECTORSIZE, 332 ("%s: I/O size not %d", __func__, ALTERA_SDCARD_SECTORSIZE)); 333 altera_sdcard_io_start_internal(sc, bp); 334 sc->as_currentbio = bp; 335 sc->as_retriesleft = ALTERA_SDCARD_RETRY_LIMIT; 336} 337 338/* 339 * Handle completed I/O. ASR is passed in to avoid reading it more than once. 340 * Return 1 if the I/O is actually complete (success, or retry limit 341 * exceeded), or 0 if not. 342 */ 343int 344altera_sdcard_io_complete(struct altera_sdcard_softc *sc, uint16_t asr) 345{ 346 struct bio *bp; 347 uint16_t rr1, mask; 348 int error; 349 350 ALTERA_SDCARD_LOCK_ASSERT(sc); 351 KASSERT(!(asr & ALTERA_SDCARD_ASR_CMDINPROGRESS), 352 ("%s: still in progress", __func__)); 353 KASSERT(asr & ALTERA_SDCARD_ASR_CARDPRESENT, 354 ("%s: card removed", __func__)); 355 356 bp = sc->as_currentbio; 357 358 /*- 359 * Handle I/O retries if an error is returned by the device. Various 360 * quirks handled in the process: 361 * 362 * 1. ALTERA_SDCARD_ASR_CMDDATAERROR is ignored for BIO_WRITE. 363 * 2. ALTERA_SDCARD_RR1_COMMANDCRCFAILED is optionally ignored for 364 * BIO_READ. 365 */ 366 error = 0; 367 rr1 = altera_sdcard_read_rr1(sc); 368 switch (bp->bio_cmd) { 369 case BIO_READ: 370 mask = ALTERA_SDCARD_RR1_ERRORMASK; 371 if (altera_sdcard_ignore_crc_errors) 372 mask &= ~ALTERA_SDCARD_RR1_COMMANDCRCFAILED; 373 if (asr & ALTERA_SDCARD_ASR_CMDTIMEOUT) 374 error = EIO; 375 else if ((asr & ALTERA_SDCARD_ASR_CMDDATAERROR) && 376 (rr1 & mask)) 377 error = EIO; 378 else 379 error = 0; 380 break; 381 382 case BIO_WRITE: 383 if (asr & ALTERA_SDCARD_ASR_CMDTIMEOUT) 384 error = EIO; 385 else 386 error = 0; 387 break; 388 389 default: 390 break; 391 } 392 if (error) { 393 /* 394 * This attempt experienced an error; possibly retry. 395 */ 396 sc->as_retriesleft--; 397 if (sc->as_retriesleft != 0) { 398 sc->as_flags |= ALTERA_SDCARD_FLAG_IOERROR; 399 altera_sdcard_io_start_internal(sc, bp); 400 return (0); 401 } 402 device_printf(sc->as_dev, "%s: %s operation block %ju length " 403 "%ju failed; asr 0x%08x (rr1: 0x%04x)\n", __func__, 404 bp->bio_cmd == BIO_READ ? "BIO_READ" : 405 (bp->bio_cmd == BIO_WRITE ? "BIO_WRITE" : "unknown"), 406 bp->bio_pblkno, bp->bio_bcount, asr, rr1); 407 sc->as_flags &= ~ALTERA_SDCARD_FLAG_IOERROR; 408 } else { 409 /* 410 * Successful I/O completion path. 411 */ 412 if (sc->as_flags & ALTERA_SDCARD_FLAG_IOERROR) { 413 device_printf(sc->as_dev, "%s: %s operation block %ju" 414 " length %ju succeeded after %d retries\n", 415 __func__, bp->bio_cmd == BIO_READ ? "BIO_READ" : 416 (bp->bio_cmd == BIO_WRITE ? "write" : "unknown"), 417 bp->bio_pblkno, bp->bio_bcount, 418 ALTERA_SDCARD_RETRY_LIMIT - sc->as_retriesleft); 419 sc->as_flags &= ~ALTERA_SDCARD_FLAG_IOERROR; 420 } 421 switch (bp->bio_cmd) { 422 case BIO_READ: 423 altera_sdcard_read_rxtx_buffer(sc, bp->bio_data, 424 bp->bio_bcount); 425 break; 426 427 case BIO_WRITE: 428 break; 429 430 default: 431 panic("%s: unsupported I/O operation %d", __func__, 432 bp->bio_cmd); 433 } 434 bp->bio_resid = 0; 435 error = 0; 436 } 437 biofinish(bp, NULL, error); 438 sc->as_currentbio = NULL; 439 return (1); 440} 441