2 * MTD SPI driver for ST M25Pxx (and similar) serial flash chips
4 * Author: Mike Lavender, mike@steroidmicros.com
6 * Copyright (c) 2005, Intec Automation Inc.
8 * Some parts are based on lart.c by Abraham Van Der Merwe
10 * Cleaned up and generalized based on mtd_dataflash.c
12 * This code is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/device.h>
21 #include <linux/interrupt.h>
22 #include <linux/mutex.h>
23 #include <linux/math64.h>
25 #include <linux/mtd/mtd.h>
26 #include <linux/mtd/partitions.h>
28 #include <linux/spi/spi.h>
29 #include <linux/spi/flash.h>
32 #define FLASH_PAGESIZE 256
35 #define OPCODE_WREN 0x06 /* Write enable */
36 #define OPCODE_RDSR 0x05 /* Read status register */
37 #define OPCODE_WRSR 0x01 /* Write status register 1 byte */
38 #define OPCODE_NORM_READ 0x03 /* Read data bytes (low frequency) */
39 #define OPCODE_FAST_READ 0x0b /* Read data bytes (high frequency) */
40 #define OPCODE_PP 0x02 /* Page program (up to 256 bytes) */
41 #define OPCODE_BE_4K 0x20 /* Erase 4KiB block */
42 #define OPCODE_BE_32K 0x52 /* Erase 32KiB block */
43 #define OPCODE_CHIP_ERASE 0xc7 /* Erase whole flash chip */
44 #define OPCODE_SE 0xd8 /* Sector erase (usually 64KiB) */
45 #define OPCODE_RDID 0x9f /* Read JEDEC ID */
47 /* Status Register bits. */
48 #define SR_WIP 1 /* Write in progress */
49 #define SR_WEL 2 /* Write enable latch */
50 /* meaning of other SR_* bits may differ between vendors */
51 #define SR_BP0 4 /* Block protect 0 */
52 #define SR_BP1 8 /* Block protect 1 */
53 #define SR_BP2 0x10 /* Block protect 2 */
54 #define SR_SRWD 0x80 /* SR write protect */
56 /* Define max times to check status register before we give up. */
57 #define MAX_READY_WAIT_COUNT 100000
60 #ifdef CONFIG_M25PXX_USE_FAST_READ
61 #define OPCODE_READ OPCODE_FAST_READ
62 #define FAST_READ_DUMMY_BYTE 1
64 #define OPCODE_READ OPCODE_NORM_READ
65 #define FAST_READ_DUMMY_BYTE 0
68 #ifdef CONFIG_MTD_PARTITIONS
69 #define mtd_has_partitions() (1)
71 #define mtd_has_partitions() (0)
74 /****************************************************************************/
77 struct spi_device *spi;
80 unsigned partitioned:1;
82 u8 command[CMD_SIZE + FAST_READ_DUMMY_BYTE];
85 static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd)
87 return container_of(mtd, struct m25p, mtd);
90 /****************************************************************************/
93 * Internal helper functions
97 * Read the status register, returning its value in the location
98 * Return the status register value.
99 * Returns negative if error occurred.
101 static int read_sr(struct m25p *flash)
104 u8 code = OPCODE_RDSR;
107 retval = spi_write_then_read(flash->spi, &code, 1, &val, 1);
110 dev_err(&flash->spi->dev, "error %d reading SR\n",
119 * Write status register 1 byte
120 * Returns negative if error occurred.
122 static int write_sr(struct m25p *flash, u8 val)
124 flash->command[0] = OPCODE_WRSR;
125 flash->command[1] = val;
127 return spi_write(flash->spi, flash->command, 2);
131 * Set write enable latch with Write Enable command.
132 * Returns negative if error occurred.
134 static inline int write_enable(struct m25p *flash)
136 u8 code = OPCODE_WREN;
138 return spi_write_then_read(flash->spi, &code, 1, NULL, 0);
143 * Service routine to read status register until ready, or timeout occurs.
144 * Returns non-zero if error.
146 static int wait_till_ready(struct m25p *flash)
151 /* one chip guarantees max 5 msec wait here after page writes,
152 * but potentially three seconds (!) after page erase.
154 for (count = 0; count < MAX_READY_WAIT_COUNT; count++) {
155 if ((sr = read_sr(flash)) < 0)
157 else if (!(sr & SR_WIP))
160 /* REVISIT sometimes sleeping would be best */
167 * Erase the whole flash memory
169 * Returns 0 if successful, non-zero otherwise.
171 static int erase_chip(struct m25p *flash)
173 DEBUG(MTD_DEBUG_LEVEL3, "%s: %s %lldKiB\n",
174 dev_name(&flash->spi->dev), __func__,
175 (long long)(flash->mtd.size >> 10));
177 /* Wait until finished previous write command. */
178 if (wait_till_ready(flash))
181 /* Send write enable, then erase commands. */
184 /* Set up command buffer. */
185 flash->command[0] = OPCODE_CHIP_ERASE;
187 spi_write(flash->spi, flash->command, 1);
193 * Erase one sector of flash memory at offset ``offset'' which is any
194 * address within the sector which should be erased.
196 * Returns 0 if successful, non-zero otherwise.
198 static int erase_sector(struct m25p *flash, u32 offset)
200 DEBUG(MTD_DEBUG_LEVEL3, "%s: %s %dKiB at 0x%08x\n",
201 dev_name(&flash->spi->dev), __func__,
202 flash->mtd.erasesize / 1024, offset);
204 /* Wait until finished previous write command. */
205 if (wait_till_ready(flash))
208 /* Send write enable, then erase commands. */
211 /* Set up command buffer. */
212 flash->command[0] = flash->erase_opcode;
213 flash->command[1] = offset >> 16;
214 flash->command[2] = offset >> 8;
215 flash->command[3] = offset;
217 spi_write(flash->spi, flash->command, CMD_SIZE);
222 /****************************************************************************/
229 * Erase an address range on the flash chip. The address range may extend
230 * one or more erase sectors. Return an error is there is a problem erasing.
232 static int m25p80_erase(struct mtd_info *mtd, struct erase_info *instr)
234 struct m25p *flash = mtd_to_m25p(mtd);
238 DEBUG(MTD_DEBUG_LEVEL2, "%s: %s %s 0x%llx, len %lld\n",
239 dev_name(&flash->spi->dev), __func__, "at",
240 (long long)instr->addr, (long long)instr->len);
243 if (instr->addr + instr->len > flash->mtd.size)
245 div_u64_rem(instr->len, mtd->erasesize, &rem);
252 mutex_lock(&flash->lock);
254 /* whole-chip erase? */
255 if (len == flash->mtd.size && erase_chip(flash)) {
256 instr->state = MTD_ERASE_FAILED;
257 mutex_unlock(&flash->lock);
260 /* REVISIT in some cases we could speed up erasing large regions
261 * by using OPCODE_SE instead of OPCODE_BE_4K. We may have set up
262 * to use "small sector erase", but that's not always optimal.
265 /* "sector"-at-a-time erase */
268 if (erase_sector(flash, addr)) {
269 instr->state = MTD_ERASE_FAILED;
270 mutex_unlock(&flash->lock);
274 addr += mtd->erasesize;
275 len -= mtd->erasesize;
279 mutex_unlock(&flash->lock);
281 instr->state = MTD_ERASE_DONE;
282 mtd_erase_callback(instr);
288 * Read an address range from the flash chip. The address range
289 * may be any size provided it is within the physical boundaries.
291 static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len,
292 size_t *retlen, u_char *buf)
294 struct m25p *flash = mtd_to_m25p(mtd);
295 struct spi_transfer t[2];
296 struct spi_message m;
298 DEBUG(MTD_DEBUG_LEVEL2, "%s: %s %s 0x%08x, len %zd\n",
299 dev_name(&flash->spi->dev), __func__, "from",
306 if (from + len > flash->mtd.size)
309 spi_message_init(&m);
310 memset(t, 0, (sizeof t));
313 * OPCODE_FAST_READ (if available) is faster.
314 * Should add 1 byte DUMMY_BYTE.
316 t[0].tx_buf = flash->command;
317 t[0].len = CMD_SIZE + FAST_READ_DUMMY_BYTE;
318 spi_message_add_tail(&t[0], &m);
322 spi_message_add_tail(&t[1], &m);
324 /* Byte count starts at zero. */
328 mutex_lock(&flash->lock);
330 /* Wait till previous write/erase is done. */
331 if (wait_till_ready(flash)) {
332 /* REVISIT status return?? */
333 mutex_unlock(&flash->lock);
337 /* FIXME switch to OPCODE_FAST_READ. It's required for higher
338 * clocks; and at this writing, every chip this driver handles
339 * supports that opcode.
342 /* Set up the write data buffer. */
343 flash->command[0] = OPCODE_READ;
344 flash->command[1] = from >> 16;
345 flash->command[2] = from >> 8;
346 flash->command[3] = from;
348 spi_sync(flash->spi, &m);
350 *retlen = m.actual_length - CMD_SIZE - FAST_READ_DUMMY_BYTE;
352 mutex_unlock(&flash->lock);
358 * Write an address range to the flash chip. Data must be written in
359 * FLASH_PAGESIZE chunks. The address range may be any size provided
360 * it is within the physical boundaries.
362 static int m25p80_write(struct mtd_info *mtd, loff_t to, size_t len,
363 size_t *retlen, const u_char *buf)
365 struct m25p *flash = mtd_to_m25p(mtd);
366 u32 page_offset, page_size;
367 struct spi_transfer t[2];
368 struct spi_message m;
370 DEBUG(MTD_DEBUG_LEVEL2, "%s: %s %s 0x%08x, len %zd\n",
371 dev_name(&flash->spi->dev), __func__, "to",
381 if (to + len > flash->mtd.size)
384 spi_message_init(&m);
385 memset(t, 0, (sizeof t));
387 t[0].tx_buf = flash->command;
389 spi_message_add_tail(&t[0], &m);
392 spi_message_add_tail(&t[1], &m);
394 mutex_lock(&flash->lock);
396 /* Wait until finished previous write command. */
397 if (wait_till_ready(flash)) {
398 mutex_unlock(&flash->lock);
404 /* Set up the opcode in the write buffer. */
405 flash->command[0] = OPCODE_PP;
406 flash->command[1] = to >> 16;
407 flash->command[2] = to >> 8;
408 flash->command[3] = to;
410 /* what page do we start with? */
411 page_offset = to % FLASH_PAGESIZE;
413 /* do all the bytes fit onto one page? */
414 if (page_offset + len <= FLASH_PAGESIZE) {
417 spi_sync(flash->spi, &m);
419 *retlen = m.actual_length - CMD_SIZE;
423 /* the size of data remaining on the first page */
424 page_size = FLASH_PAGESIZE - page_offset;
426 t[1].len = page_size;
427 spi_sync(flash->spi, &m);
429 *retlen = m.actual_length - CMD_SIZE;
431 /* write everything in PAGESIZE chunks */
432 for (i = page_size; i < len; i += page_size) {
434 if (page_size > FLASH_PAGESIZE)
435 page_size = FLASH_PAGESIZE;
437 /* write the next page to flash */
438 flash->command[1] = (to + i) >> 16;
439 flash->command[2] = (to + i) >> 8;
440 flash->command[3] = (to + i);
442 t[1].tx_buf = buf + i;
443 t[1].len = page_size;
445 wait_till_ready(flash);
449 spi_sync(flash->spi, &m);
452 *retlen += m.actual_length - CMD_SIZE;
456 mutex_unlock(&flash->lock);
462 /****************************************************************************/
465 * SPI device driver setup and teardown
471 /* JEDEC id zero means "no ID" (most older chips); otherwise it has
472 * a high byte of zero plus three data bytes: the manufacturer id,
473 * then a two byte device id.
478 /* The size listed here is what works with OPCODE_SE, which isn't
479 * necessarily called a "sector" by the vendor.
481 unsigned sector_size;
485 #define SECT_4K 0x01 /* OPCODE_BE_4K works uniformly */
489 /* NOTE: double check command sets and memory organization when you add
490 * more flash chips. This current list focusses on newer chips, which
491 * have been converging on command sets which including JEDEC ID.
493 static struct flash_info __devinitdata m25p_data [] = {
495 /* Atmel -- some are (confusingly) marketed as "DataFlash" */
496 { "at25fs010", 0x1f6601, 0, 32 * 1024, 4, SECT_4K, },
497 { "at25fs040", 0x1f6604, 0, 64 * 1024, 8, SECT_4K, },
499 { "at25df041a", 0x1f4401, 0, 64 * 1024, 8, SECT_4K, },
500 { "at25df641", 0x1f4800, 0, 64 * 1024, 128, SECT_4K, },
502 { "at26f004", 0x1f0400, 0, 64 * 1024, 8, SECT_4K, },
503 { "at26df081a", 0x1f4501, 0, 64 * 1024, 16, SECT_4K, },
504 { "at26df161a", 0x1f4601, 0, 64 * 1024, 32, SECT_4K, },
505 { "at26df321", 0x1f4701, 0, 64 * 1024, 64, SECT_4K, },
507 /* Spansion -- single (large) sector size only, at least
508 * for the chips listed here (without boot sectors).
510 { "s25sl004a", 0x010212, 0, 64 * 1024, 8, },
511 { "s25sl008a", 0x010213, 0, 64 * 1024, 16, },
512 { "s25sl016a", 0x010214, 0, 64 * 1024, 32, },
513 { "s25sl032a", 0x010215, 0, 64 * 1024, 64, },
514 { "s25sl064a", 0x010216, 0, 64 * 1024, 128, },
515 { "s25sl12800", 0x012018, 0x0300, 256 * 1024, 64, },
516 { "s25sl12801", 0x012018, 0x0301, 64 * 1024, 256, },
518 /* SST -- large erase sizes are "overlays", "sectors" are 4K */
519 { "sst25vf040b", 0xbf258d, 0, 64 * 1024, 8, SECT_4K, },
520 { "sst25vf080b", 0xbf258e, 0, 64 * 1024, 16, SECT_4K, },
521 { "sst25vf016b", 0xbf2541, 0, 64 * 1024, 32, SECT_4K, },
522 { "sst25vf032b", 0xbf254a, 0, 64 * 1024, 64, SECT_4K, },
524 /* ST Microelectronics -- newer production may have feature updates */
525 { "m25p05", 0x202010, 0, 32 * 1024, 2, },
526 { "m25p10", 0x202011, 0, 32 * 1024, 4, },
527 { "m25p20", 0x202012, 0, 64 * 1024, 4, },
528 { "m25p40", 0x202013, 0, 64 * 1024, 8, },
529 { "m25p80", 0, 0, 64 * 1024, 16, },
530 { "m25p16", 0x202015, 0, 64 * 1024, 32, },
531 { "m25p32", 0x202016, 0, 64 * 1024, 64, },
532 { "m25p64", 0x202017, 0, 64 * 1024, 128, },
533 { "m25p128", 0x202018, 0, 256 * 1024, 64, },
535 { "m45pe80", 0x204014, 0, 64 * 1024, 16, },
536 { "m45pe16", 0x204015, 0, 64 * 1024, 32, },
538 { "m25pe80", 0x208014, 0, 64 * 1024, 16, },
539 { "m25pe16", 0x208015, 0, 64 * 1024, 32, SECT_4K, },
541 /* Winbond -- w25x "blocks" are 64K, "sectors" are 4KiB */
542 { "w25x10", 0xef3011, 0, 64 * 1024, 2, SECT_4K, },
543 { "w25x20", 0xef3012, 0, 64 * 1024, 4, SECT_4K, },
544 { "w25x40", 0xef3013, 0, 64 * 1024, 8, SECT_4K, },
545 { "w25x80", 0xef3014, 0, 64 * 1024, 16, SECT_4K, },
546 { "w25x16", 0xef3015, 0, 64 * 1024, 32, SECT_4K, },
547 { "w25x32", 0xef3016, 0, 64 * 1024, 64, SECT_4K, },
548 { "w25x64", 0xef3017, 0, 64 * 1024, 128, SECT_4K, },
551 static struct flash_info *__devinit jedec_probe(struct spi_device *spi)
554 u8 code = OPCODE_RDID;
558 struct flash_info *info;
560 /* JEDEC also defines an optional "extended device information"
561 * string for after vendor-specific data, after the three bytes
562 * we use here. Supporting some chips might require using it.
564 tmp = spi_write_then_read(spi, &code, 1, id, 5);
566 DEBUG(MTD_DEBUG_LEVEL0, "%s: error %d reading JEDEC ID\n",
567 dev_name(&spi->dev), tmp);
576 ext_jedec = id[3] << 8 | id[4];
578 for (tmp = 0, info = m25p_data;
579 tmp < ARRAY_SIZE(m25p_data);
581 if (info->jedec_id == jedec) {
582 if (info->ext_id != 0 && info->ext_id != ext_jedec)
587 dev_err(&spi->dev, "unrecognized JEDEC id %06x\n", jedec);
593 * board specific setup should have ensured the SPI clock used here
594 * matches what the READ command supports, at least until this driver
595 * understands FAST_READ (for clocks over 25 MHz).
597 static int __devinit m25p_probe(struct spi_device *spi)
599 struct flash_platform_data *data;
601 struct flash_info *info;
604 /* Platform data helps sort out which chip type we have, as
605 * well as how this board partitions it. If we don't have
606 * a chip ID, try the JEDEC id commands; they'll work for most
607 * newer chips, even if we don't recognize the particular chip.
609 data = spi->dev.platform_data;
610 if (data && data->type) {
611 for (i = 0, info = m25p_data;
612 i < ARRAY_SIZE(m25p_data);
614 if (strcmp(data->type, info->name) == 0)
618 /* unrecognized chip? */
619 if (i == ARRAY_SIZE(m25p_data)) {
620 DEBUG(MTD_DEBUG_LEVEL0, "%s: unrecognized id %s\n",
621 dev_name(&spi->dev), data->type);
624 /* recognized; is that chip really what's there? */
625 } else if (info->jedec_id) {
626 struct flash_info *chip = jedec_probe(spi);
628 if (!chip || chip != info) {
629 dev_warn(&spi->dev, "found %s, expected %s\n",
630 chip ? chip->name : "UNKNOWN",
636 info = jedec_probe(spi);
641 flash = kzalloc(sizeof *flash, GFP_KERNEL);
646 mutex_init(&flash->lock);
647 dev_set_drvdata(&spi->dev, flash);
650 * Atmel serial flash tend to power up
651 * with the software protection bits set
654 if (info->jedec_id >> 16 == 0x1f) {
659 if (data && data->name)
660 flash->mtd.name = data->name;
662 flash->mtd.name = dev_name(&spi->dev);
664 flash->mtd.type = MTD_NORFLASH;
665 flash->mtd.writesize = 1;
666 flash->mtd.flags = MTD_CAP_NORFLASH;
667 flash->mtd.size = info->sector_size * info->n_sectors;
668 flash->mtd.erase = m25p80_erase;
669 flash->mtd.read = m25p80_read;
670 flash->mtd.write = m25p80_write;
672 /* prefer "small sector" erase if possible */
673 if (info->flags & SECT_4K) {
674 flash->erase_opcode = OPCODE_BE_4K;
675 flash->mtd.erasesize = 4096;
677 flash->erase_opcode = OPCODE_SE;
678 flash->mtd.erasesize = info->sector_size;
681 dev_info(&spi->dev, "%s (%lld Kbytes)\n", info->name,
682 (long long)flash->mtd.size >> 10);
684 DEBUG(MTD_DEBUG_LEVEL2,
685 "mtd .name = %s, .size = 0x%llx (%lldMiB) "
686 ".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
688 (long long)flash->mtd.size, (long long)(flash->mtd.size >> 20),
689 flash->mtd.erasesize, flash->mtd.erasesize / 1024,
690 flash->mtd.numeraseregions);
692 if (flash->mtd.numeraseregions)
693 for (i = 0; i < flash->mtd.numeraseregions; i++)
694 DEBUG(MTD_DEBUG_LEVEL2,
695 "mtd.eraseregions[%d] = { .offset = 0x%llx, "
696 ".erasesize = 0x%.8x (%uKiB), "
697 ".numblocks = %d }\n",
698 i, (long long)flash->mtd.eraseregions[i].offset,
699 flash->mtd.eraseregions[i].erasesize,
700 flash->mtd.eraseregions[i].erasesize / 1024,
701 flash->mtd.eraseregions[i].numblocks);
704 /* partitions should match sector boundaries; and it may be good to
705 * use readonly partitions for writeprotected sectors (BP2..BP0).
707 if (mtd_has_partitions()) {
708 struct mtd_partition *parts = NULL;
711 #ifdef CONFIG_MTD_CMDLINE_PARTS
712 static const char *part_probes[] = { "cmdlinepart", NULL, };
714 nr_parts = parse_mtd_partitions(&flash->mtd,
715 part_probes, &parts, 0);
718 if (nr_parts <= 0 && data && data->parts) {
720 nr_parts = data->nr_parts;
724 for (i = 0; i < nr_parts; i++) {
725 DEBUG(MTD_DEBUG_LEVEL2, "partitions[%d] = "
726 "{.name = %s, .offset = 0x%llx, "
727 ".size = 0x%llx (%lldKiB) }\n",
729 (long long)parts[i].offset,
730 (long long)parts[i].size,
731 (long long)(parts[i].size >> 10));
733 flash->partitioned = 1;
734 return add_mtd_partitions(&flash->mtd, parts, nr_parts);
736 } else if (data->nr_parts)
737 dev_warn(&spi->dev, "ignoring %d default partitions on %s\n",
738 data->nr_parts, data->name);
740 return add_mtd_device(&flash->mtd) == 1 ? -ENODEV : 0;
744 static int __devexit m25p_remove(struct spi_device *spi)
746 struct m25p *flash = dev_get_drvdata(&spi->dev);
749 /* Clean up MTD stuff. */
750 if (mtd_has_partitions() && flash->partitioned)
751 status = del_mtd_partitions(&flash->mtd);
753 status = del_mtd_device(&flash->mtd);
760 static struct spi_driver m25p80_driver = {
763 .bus = &spi_bus_type,
764 .owner = THIS_MODULE,
767 .remove = __devexit_p(m25p_remove),
769 /* REVISIT: many of these chips have deep power-down modes, which
770 * should clearly be entered on suspend() to minimize power use.
771 * And also when they're otherwise idle...
776 static int m25p80_init(void)
778 return spi_register_driver(&m25p80_driver);
782 static void m25p80_exit(void)
784 spi_unregister_driver(&m25p80_driver);
788 module_init(m25p80_init);
789 module_exit(m25p80_exit);
791 MODULE_LICENSE("GPL");
792 MODULE_AUTHOR("Mike Lavender");
793 MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips");