1 /* 2 * Simulate a SPI flash 3 * 4 * Copyright (c) 2011-2013 The Chromium OS Authors. 5 * See file CREDITS for list of people who contributed to this 6 * project. 7 * 8 * Licensed under the GPL-2 or later. 9 */ 10 11 #include <common.h> 12 #include <dm.h> 13 #include <malloc.h> 14 #include <spi.h> 15 #include <os.h> 16 17 #include <spi_flash.h> 18 #include "sf_internal.h" 19 20 #include <asm/getopt.h> 21 #include <asm/spi.h> 22 #include <asm/state.h> 23 #include <dm/device-internal.h> 24 #include <dm/lists.h> 25 #include <dm/uclass-internal.h> 26 27 DECLARE_GLOBAL_DATA_PTR; 28 29 /* 30 * The different states that our SPI flash transitions between. 31 * We need to keep track of this across multiple xfer calls since 32 * the SPI bus could possibly call down into us multiple times. 33 */ 34 enum sandbox_sf_state { 35 SF_CMD, /* default state -- we're awaiting a command */ 36 SF_ID, /* read the flash's (jedec) ID code */ 37 SF_ADDR, /* processing the offset in the flash to read/etc... */ 38 SF_READ, /* reading data from the flash */ 39 SF_WRITE, /* writing data to the flash, i.e. page programming */ 40 SF_ERASE, /* erase the flash */ 41 SF_READ_STATUS, /* read the flash's status register */ 42 SF_READ_STATUS1, /* read the flash's status register upper 8 bits*/ 43 SF_WRITE_STATUS, /* write the flash's status register */ 44 }; 45 46 static const char *sandbox_sf_state_name(enum sandbox_sf_state state) 47 { 48 static const char * const states[] = { 49 "CMD", "ID", "ADDR", "READ", "WRITE", "ERASE", "READ_STATUS", 50 "READ_STATUS1", "WRITE_STATUS", 51 }; 52 return states[state]; 53 } 54 55 /* Bits for the status register */ 56 #define STAT_WIP (1 << 0) 57 #define STAT_WEL (1 << 1) 58 59 /* Assume all SPI flashes have 3 byte addresses since they do atm */ 60 #define SF_ADDR_LEN 3 61 62 #define IDCODE_LEN 3 63 64 /* Used to quickly bulk erase backing store */ 65 static u8 sandbox_sf_0xff[0x1000]; 66 67 /* Internal state data for each SPI flash */ 68 struct sandbox_spi_flash { 69 unsigned int cs; /* Chip select we are attached to */ 70 /* 71 * As we receive data over the SPI bus, our flash transitions 72 * between states. For example, we start off in the SF_CMD 73 * state where the first byte tells us what operation to perform 74 * (such as read or write the flash). But the operation itself 75 * can go through a few states such as first reading in the 76 * offset in the flash to perform the requested operation. 77 * Thus "state" stores the exact state that our machine is in 78 * while "cmd" stores the overall command we're processing. 79 */ 80 enum sandbox_sf_state state; 81 uint cmd; 82 /* Erase size of current erase command */ 83 uint erase_size; 84 /* Current position in the flash; used when reading/writing/etc... */ 85 uint off; 86 /* How many address bytes we've consumed */ 87 uint addr_bytes, pad_addr_bytes; 88 /* The current flash status (see STAT_XXX defines above) */ 89 u16 status; 90 /* Data describing the flash we're emulating */ 91 const struct spi_flash_params *data; 92 /* The file on disk to serv up data from */ 93 int fd; 94 }; 95 96 struct sandbox_spi_flash_plat_data { 97 const char *filename; 98 const char *device_name; 99 int bus; 100 int cs; 101 }; 102 103 /** 104 * This is a very strange probe function. If it has platform data (which may 105 * have come from the device tree) then this function gets the filename and 106 * device type from there. Failing that it looks at the command line 107 * parameter. 108 */ 109 static int sandbox_sf_probe(struct udevice *dev) 110 { 111 /* spec = idcode:file */ 112 struct sandbox_spi_flash *sbsf = dev_get_priv(dev); 113 const char *file; 114 size_t len, idname_len; 115 const struct spi_flash_params *data; 116 struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev); 117 struct sandbox_state *state = state_get_current(); 118 struct udevice *bus = dev->parent; 119 const char *spec = NULL; 120 int ret = 0; 121 int cs = -1; 122 int i; 123 124 debug("%s: bus %d, looking for emul=%p: ", __func__, bus->seq, dev); 125 if (bus->seq >= 0 && bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS) { 126 for (i = 0; i < CONFIG_SANDBOX_SPI_MAX_CS; i++) { 127 if (state->spi[bus->seq][i].emul == dev) 128 cs = i; 129 } 130 } 131 if (cs == -1) { 132 printf("Error: Unknown chip select for device '%s'", 133 dev->name); 134 return -EINVAL; 135 } 136 debug("found at cs %d\n", cs); 137 138 if (!pdata->filename) { 139 struct sandbox_state *state = state_get_current(); 140 141 assert(bus->seq != -1); 142 if (bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS) 143 spec = state->spi[bus->seq][cs].spec; 144 if (!spec) 145 return -ENOENT; 146 147 file = strchr(spec, ':'); 148 if (!file) { 149 printf("sandbox_sf: unable to parse file\n"); 150 ret = -EINVAL; 151 goto error; 152 } 153 idname_len = file - spec; 154 pdata->filename = file + 1; 155 pdata->device_name = spec; 156 ++file; 157 } else { 158 spec = strchr(pdata->device_name, ','); 159 if (spec) 160 spec++; 161 else 162 spec = pdata->device_name; 163 idname_len = strlen(spec); 164 } 165 debug("%s: device='%s'\n", __func__, spec); 166 167 for (data = spi_flash_params_table; data->name; data++) { 168 len = strlen(data->name); 169 if (idname_len != len) 170 continue; 171 if (!strncasecmp(spec, data->name, len)) 172 break; 173 } 174 if (!data->name) { 175 printf("sandbox_sf: unknown flash '%*s'\n", (int)idname_len, 176 spec); 177 ret = -EINVAL; 178 goto error; 179 } 180 181 if (sandbox_sf_0xff[0] == 0x00) 182 memset(sandbox_sf_0xff, 0xff, sizeof(sandbox_sf_0xff)); 183 184 sbsf->fd = os_open(pdata->filename, 02); 185 if (sbsf->fd == -1) { 186 free(sbsf); 187 printf("sandbox_sf: unable to open file '%s'\n", 188 pdata->filename); 189 ret = -EIO; 190 goto error; 191 } 192 193 sbsf->data = data; 194 sbsf->cs = cs; 195 196 return 0; 197 198 error: 199 return ret; 200 } 201 202 static int sandbox_sf_remove(struct udevice *dev) 203 { 204 struct sandbox_spi_flash *sbsf = dev_get_priv(dev); 205 206 os_close(sbsf->fd); 207 208 return 0; 209 } 210 211 static void sandbox_sf_cs_activate(struct udevice *dev) 212 { 213 struct sandbox_spi_flash *sbsf = dev_get_priv(dev); 214 215 debug("sandbox_sf: CS activated; state is fresh!\n"); 216 217 /* CS is asserted, so reset state */ 218 sbsf->off = 0; 219 sbsf->addr_bytes = 0; 220 sbsf->pad_addr_bytes = 0; 221 sbsf->state = SF_CMD; 222 sbsf->cmd = SF_CMD; 223 } 224 225 static void sandbox_sf_cs_deactivate(struct udevice *dev) 226 { 227 debug("sandbox_sf: CS deactivated; cmd done processing!\n"); 228 } 229 230 /* 231 * There are times when the data lines are allowed to tristate. What 232 * is actually sensed on the line depends on the hardware. It could 233 * always be 0xFF/0x00 (if there are pull ups/downs), or things could 234 * float and so we'd get garbage back. This func encapsulates that 235 * scenario so we can worry about the details here. 236 */ 237 static void sandbox_spi_tristate(u8 *buf, uint len) 238 { 239 /* XXX: make this into a user config option ? */ 240 memset(buf, 0xff, len); 241 } 242 243 /* Figure out what command this stream is telling us to do */ 244 static int sandbox_sf_process_cmd(struct sandbox_spi_flash *sbsf, const u8 *rx, 245 u8 *tx) 246 { 247 enum sandbox_sf_state oldstate = sbsf->state; 248 249 /* We need to output a byte for the cmd byte we just ate */ 250 if (tx) 251 sandbox_spi_tristate(tx, 1); 252 253 sbsf->cmd = rx[0]; 254 switch (sbsf->cmd) { 255 case CMD_READ_ID: 256 sbsf->state = SF_ID; 257 sbsf->cmd = SF_ID; 258 break; 259 case CMD_READ_ARRAY_FAST: 260 sbsf->pad_addr_bytes = 1; 261 case CMD_READ_ARRAY_SLOW: 262 case CMD_PAGE_PROGRAM: 263 sbsf->state = SF_ADDR; 264 break; 265 case CMD_WRITE_DISABLE: 266 debug(" write disabled\n"); 267 sbsf->status &= ~STAT_WEL; 268 break; 269 case CMD_READ_STATUS: 270 sbsf->state = SF_READ_STATUS; 271 break; 272 case CMD_READ_STATUS1: 273 sbsf->state = SF_READ_STATUS1; 274 break; 275 case CMD_WRITE_ENABLE: 276 debug(" write enabled\n"); 277 sbsf->status |= STAT_WEL; 278 break; 279 case CMD_WRITE_STATUS: 280 sbsf->state = SF_WRITE_STATUS; 281 break; 282 default: { 283 int flags = sbsf->data->flags; 284 285 /* we only support erase here */ 286 if (sbsf->cmd == CMD_ERASE_CHIP) { 287 sbsf->erase_size = sbsf->data->sector_size * 288 sbsf->data->nr_sectors; 289 } else if (sbsf->cmd == CMD_ERASE_4K && (flags & SECT_4K)) { 290 sbsf->erase_size = 4 << 10; 291 } else if (sbsf->cmd == CMD_ERASE_32K && (flags & SECT_32K)) { 292 sbsf->erase_size = 32 << 10; 293 } else if (sbsf->cmd == CMD_ERASE_64K && 294 !(flags & (SECT_4K | SECT_32K))) { 295 sbsf->erase_size = 64 << 10; 296 } else { 297 debug(" cmd unknown: %#x\n", sbsf->cmd); 298 return -EIO; 299 } 300 sbsf->state = SF_ADDR; 301 break; 302 } 303 } 304 305 if (oldstate != sbsf->state) 306 debug(" cmd: transition to %s state\n", 307 sandbox_sf_state_name(sbsf->state)); 308 309 return 0; 310 } 311 312 int sandbox_erase_part(struct sandbox_spi_flash *sbsf, int size) 313 { 314 int todo; 315 int ret; 316 317 while (size > 0) { 318 todo = min(size, (int)sizeof(sandbox_sf_0xff)); 319 ret = os_write(sbsf->fd, sandbox_sf_0xff, todo); 320 if (ret != todo) 321 return ret; 322 size -= todo; 323 } 324 325 return 0; 326 } 327 328 static int sandbox_sf_xfer(struct udevice *dev, unsigned int bitlen, 329 const void *rxp, void *txp, unsigned long flags) 330 { 331 struct sandbox_spi_flash *sbsf = dev_get_priv(dev); 332 const uint8_t *rx = rxp; 333 uint8_t *tx = txp; 334 uint cnt, pos = 0; 335 int bytes = bitlen / 8; 336 int ret; 337 338 debug("sandbox_sf: state:%x(%s) bytes:%u\n", sbsf->state, 339 sandbox_sf_state_name(sbsf->state), bytes); 340 341 if ((flags & SPI_XFER_BEGIN)) 342 sandbox_sf_cs_activate(dev); 343 344 if (sbsf->state == SF_CMD) { 345 /* Figure out the initial state */ 346 ret = sandbox_sf_process_cmd(sbsf, rx, tx); 347 if (ret) 348 return ret; 349 ++pos; 350 } 351 352 /* Process the remaining data */ 353 while (pos < bytes) { 354 switch (sbsf->state) { 355 case SF_ID: { 356 u8 id; 357 358 debug(" id: off:%u tx:", sbsf->off); 359 if (sbsf->off < IDCODE_LEN) { 360 /* Extract correct byte from ID 0x00aabbcc */ 361 id = sbsf->data->jedec >> 362 (8 * (IDCODE_LEN - 1 - sbsf->off)); 363 } else { 364 id = 0; 365 } 366 debug("%d %02x\n", sbsf->off, id); 367 tx[pos++] = id; 368 ++sbsf->off; 369 break; 370 } 371 case SF_ADDR: 372 debug(" addr: bytes:%u rx:%02x ", sbsf->addr_bytes, 373 rx[pos]); 374 375 if (sbsf->addr_bytes++ < SF_ADDR_LEN) 376 sbsf->off = (sbsf->off << 8) | rx[pos]; 377 debug("addr:%06x\n", sbsf->off); 378 379 if (tx) 380 sandbox_spi_tristate(&tx[pos], 1); 381 pos++; 382 383 /* See if we're done processing */ 384 if (sbsf->addr_bytes < 385 SF_ADDR_LEN + sbsf->pad_addr_bytes) 386 break; 387 388 /* Next state! */ 389 if (os_lseek(sbsf->fd, sbsf->off, OS_SEEK_SET) < 0) { 390 puts("sandbox_sf: os_lseek() failed"); 391 return -EIO; 392 } 393 switch (sbsf->cmd) { 394 case CMD_READ_ARRAY_FAST: 395 case CMD_READ_ARRAY_SLOW: 396 sbsf->state = SF_READ; 397 break; 398 case CMD_PAGE_PROGRAM: 399 sbsf->state = SF_WRITE; 400 break; 401 default: 402 /* assume erase state ... */ 403 sbsf->state = SF_ERASE; 404 goto case_sf_erase; 405 } 406 debug(" cmd: transition to %s state\n", 407 sandbox_sf_state_name(sbsf->state)); 408 break; 409 case SF_READ: 410 /* 411 * XXX: need to handle exotic behavior: 412 * - reading past end of device 413 */ 414 415 cnt = bytes - pos; 416 debug(" tx: read(%u)\n", cnt); 417 assert(tx); 418 ret = os_read(sbsf->fd, tx + pos, cnt); 419 if (ret < 0) { 420 puts("sandbox_sf: os_read() failed\n"); 421 return -EIO; 422 } 423 pos += ret; 424 break; 425 case SF_READ_STATUS: 426 debug(" read status: %#x\n", sbsf->status); 427 cnt = bytes - pos; 428 memset(tx + pos, sbsf->status, cnt); 429 pos += cnt; 430 break; 431 case SF_READ_STATUS1: 432 debug(" read status: %#x\n", sbsf->status); 433 cnt = bytes - pos; 434 memset(tx + pos, sbsf->status >> 8, cnt); 435 pos += cnt; 436 break; 437 case SF_WRITE_STATUS: 438 debug(" write status: %#x (ignored)\n", rx[pos]); 439 pos = bytes; 440 break; 441 case SF_WRITE: 442 /* 443 * XXX: need to handle exotic behavior: 444 * - unaligned addresses 445 * - more than a page (256) worth of data 446 * - reading past end of device 447 */ 448 if (!(sbsf->status & STAT_WEL)) { 449 puts("sandbox_sf: write enable not set before write\n"); 450 goto done; 451 } 452 453 cnt = bytes - pos; 454 debug(" rx: write(%u)\n", cnt); 455 if (tx) 456 sandbox_spi_tristate(&tx[pos], cnt); 457 ret = os_write(sbsf->fd, rx + pos, cnt); 458 if (ret < 0) { 459 puts("sandbox_spi: os_write() failed\n"); 460 return -EIO; 461 } 462 pos += ret; 463 sbsf->status &= ~STAT_WEL; 464 break; 465 case SF_ERASE: 466 case_sf_erase: { 467 if (!(sbsf->status & STAT_WEL)) { 468 puts("sandbox_sf: write enable not set before erase\n"); 469 goto done; 470 } 471 472 /* verify address is aligned */ 473 if (sbsf->off & (sbsf->erase_size - 1)) { 474 debug(" sector erase: cmd:%#x needs align:%#x, but we got %#x\n", 475 sbsf->cmd, sbsf->erase_size, 476 sbsf->off); 477 sbsf->status &= ~STAT_WEL; 478 goto done; 479 } 480 481 debug(" sector erase addr: %u, size: %u\n", sbsf->off, 482 sbsf->erase_size); 483 484 cnt = bytes - pos; 485 if (tx) 486 sandbox_spi_tristate(&tx[pos], cnt); 487 pos += cnt; 488 489 /* 490 * TODO(vapier@gentoo.org): latch WIP in status, and 491 * delay before clearing it ? 492 */ 493 ret = sandbox_erase_part(sbsf, sbsf->erase_size); 494 sbsf->status &= ~STAT_WEL; 495 if (ret) { 496 debug("sandbox_sf: Erase failed\n"); 497 goto done; 498 } 499 goto done; 500 } 501 default: 502 debug(" ??? no idea what to do ???\n"); 503 goto done; 504 } 505 } 506 507 done: 508 if (flags & SPI_XFER_END) 509 sandbox_sf_cs_deactivate(dev); 510 return pos == bytes ? 0 : -EIO; 511 } 512 513 int sandbox_sf_ofdata_to_platdata(struct udevice *dev) 514 { 515 struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev); 516 const void *blob = gd->fdt_blob; 517 int node = dev->of_offset; 518 519 pdata->filename = fdt_getprop(blob, node, "sandbox,filename", NULL); 520 pdata->device_name = fdt_getprop(blob, node, "compatible", NULL); 521 if (!pdata->filename || !pdata->device_name) { 522 debug("%s: Missing properties, filename=%s, device_name=%s\n", 523 __func__, pdata->filename, pdata->device_name); 524 return -EINVAL; 525 } 526 527 return 0; 528 } 529 530 static const struct dm_spi_emul_ops sandbox_sf_emul_ops = { 531 .xfer = sandbox_sf_xfer, 532 }; 533 534 #ifdef CONFIG_SPI_FLASH 535 static int sandbox_cmdline_cb_spi_sf(struct sandbox_state *state, 536 const char *arg) 537 { 538 unsigned long bus, cs; 539 const char *spec = sandbox_spi_parse_spec(arg, &bus, &cs); 540 541 if (!spec) 542 return 1; 543 544 /* 545 * It is safe to not make a copy of 'spec' because it comes from the 546 * command line. 547 * 548 * TODO(sjg@chromium.org): It would be nice if we could parse the 549 * spec here, but the problem is that no U-Boot init has been done 550 * yet. Perhaps we can figure something out. 551 */ 552 state->spi[bus][cs].spec = spec; 553 return 0; 554 } 555 SANDBOX_CMDLINE_OPT(spi_sf, 1, "connect a SPI flash: <bus>:<cs>:<id>:<file>"); 556 557 int sandbox_sf_bind_emul(struct sandbox_state *state, int busnum, int cs, 558 struct udevice *bus, int of_offset, const char *spec) 559 { 560 struct udevice *emul; 561 char name[20], *str; 562 struct driver *drv; 563 int ret; 564 565 /* now the emulator */ 566 strncpy(name, spec, sizeof(name) - 6); 567 name[sizeof(name) - 6] = '\0'; 568 strcat(name, "-emul"); 569 str = strdup(name); 570 if (!str) 571 return -ENOMEM; 572 drv = lists_driver_lookup_name("sandbox_sf_emul"); 573 if (!drv) { 574 puts("Cannot find sandbox_sf_emul driver\n"); 575 return -ENOENT; 576 } 577 ret = device_bind(bus, drv, str, NULL, of_offset, &emul); 578 if (ret) { 579 printf("Cannot create emul device for spec '%s' (err=%d)\n", 580 spec, ret); 581 return ret; 582 } 583 state->spi[busnum][cs].emul = emul; 584 585 return 0; 586 } 587 588 void sandbox_sf_unbind_emul(struct sandbox_state *state, int busnum, int cs) 589 { 590 state->spi[busnum][cs].emul = NULL; 591 } 592 593 static int sandbox_sf_bind_bus_cs(struct sandbox_state *state, int busnum, 594 int cs, const char *spec) 595 { 596 struct udevice *bus, *slave; 597 int ret; 598 599 ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, true, &bus); 600 if (ret) { 601 printf("Invalid bus %d for spec '%s' (err=%d)\n", busnum, 602 spec, ret); 603 return ret; 604 } 605 ret = spi_find_chip_select(bus, cs, &slave); 606 if (!ret) { 607 printf("Chip select %d already exists for spec '%s'\n", cs, 608 spec); 609 return -EEXIST; 610 } 611 612 ret = device_bind_driver(bus, "spi_flash_std", spec, &slave); 613 if (ret) 614 return ret; 615 616 return sandbox_sf_bind_emul(state, busnum, cs, bus, -1, spec); 617 } 618 619 int sandbox_spi_get_emul(struct sandbox_state *state, 620 struct udevice *bus, struct udevice *slave, 621 struct udevice **emulp) 622 { 623 struct sandbox_spi_info *info; 624 int busnum = bus->seq; 625 int cs = spi_chip_select(slave); 626 int ret; 627 628 info = &state->spi[busnum][cs]; 629 if (!info->emul) { 630 /* Use the same device tree node as the SPI flash device */ 631 debug("%s: busnum=%u, cs=%u: binding SPI flash emulation: ", 632 __func__, busnum, cs); 633 ret = sandbox_sf_bind_emul(state, busnum, cs, bus, 634 slave->of_offset, slave->name); 635 if (ret) { 636 debug("failed (err=%d)\n", ret); 637 return ret; 638 } 639 debug("OK\n"); 640 } 641 *emulp = info->emul; 642 643 return 0; 644 } 645 646 int dm_scan_other(bool pre_reloc_only) 647 { 648 struct sandbox_state *state = state_get_current(); 649 int busnum, cs; 650 651 if (pre_reloc_only) 652 return 0; 653 for (busnum = 0; busnum < CONFIG_SANDBOX_SPI_MAX_BUS; busnum++) { 654 for (cs = 0; cs < CONFIG_SANDBOX_SPI_MAX_CS; cs++) { 655 const char *spec = state->spi[busnum][cs].spec; 656 int ret; 657 658 if (spec) { 659 ret = sandbox_sf_bind_bus_cs(state, busnum, 660 cs, spec); 661 if (ret) { 662 debug("%s: Bind failed for bus %d, cs %d\n", 663 __func__, busnum, cs); 664 return ret; 665 } 666 } 667 } 668 } 669 670 return 0; 671 } 672 #endif 673 674 static const struct udevice_id sandbox_sf_ids[] = { 675 { .compatible = "sandbox,spi-flash" }, 676 { } 677 }; 678 679 U_BOOT_DRIVER(sandbox_sf_emul) = { 680 .name = "sandbox_sf_emul", 681 .id = UCLASS_SPI_EMUL, 682 .of_match = sandbox_sf_ids, 683 .ofdata_to_platdata = sandbox_sf_ofdata_to_platdata, 684 .probe = sandbox_sf_probe, 685 .remove = sandbox_sf_remove, 686 .priv_auto_alloc_size = sizeof(struct sandbox_spi_flash), 687 .platdata_auto_alloc_size = sizeof(struct sandbox_spi_flash_plat_data), 688 .ops = &sandbox_sf_emul_ops, 689 }; 690