/*
- * MTD SPI driver for ST M25Pxx flash chips
+ * MTD SPI driver for ST M25Pxx (and similar) serial flash chips
*
* Author: Mike Lavender, mike@steroidmicros.com
*
#include <linux/spi/flash.h>
-/* NOTE: AT 25F and SST 25LF series are very similar,
- * as are other newer Atmel dataflash chips (AT26),
- * but commands for sector erase and chip id differ...
- */
-
#define FLASH_PAGESIZE 256
/* Flash opcodes. */
-#define OPCODE_WREN 6 /* Write enable */
-#define OPCODE_RDSR 5 /* Read status register */
-#define OPCODE_READ 3 /* Read data bytes */
-#define OPCODE_PP 2 /* Page program */
-#define OPCODE_SE 0xd8 /* Sector erase */
-#define OPCODE_RES 0xab /* Read Electronic Signature */
+#define OPCODE_WREN 0x06 /* Write enable */
+#define OPCODE_RDSR 0x05 /* Read status register */
+#define OPCODE_READ 0x03 /* Read data bytes (low frequency) */
+#define OPCODE_FAST_READ 0x0b /* Read data bytes (high frequency) */
+#define OPCODE_PP 0x02 /* Page program (up to 256 bytes) */
+#define OPCODE_BE_4K 0x20 /* Erase 4K block */
+#define OPCODE_BE_32K 0x52 /* Erase 32K block */
+#define OPCODE_SE 0xd8 /* Sector erase (usually 64K) */
#define OPCODE_RDID 0x9f /* Read JEDEC ID */
/* Status Register bits. */
#define SR_WIP 1 /* Write in progress */
#define SR_WEL 2 /* Write enable latch */
+/* meaning of other SR_* bits may differ between vendors */
#define SR_BP0 4 /* Block protect 0 */
#define SR_BP1 8 /* Block protect 1 */
#define SR_BP2 0x10 /* Block protect 2 */
struct spi_device *spi;
struct mutex lock;
struct mtd_info mtd;
- unsigned partitioned;
+ unsigned partitioned:1;
+ u8 erase_opcode;
u8 command[4];
};
*/
static int erase_sector(struct m25p *flash, u32 offset)
{
- DEBUG(MTD_DEBUG_LEVEL3, "%s: %s at 0x%08x\n", flash->spi->dev.bus_id,
- __FUNCTION__, offset);
+ DEBUG(MTD_DEBUG_LEVEL3, "%s: %s %dK at 0x%08x\n",
+ flash->spi->dev.bus_id, __FUNCTION__,
+ flash->mtd.erasesize / 1024, offset);
/* Wait until finished previous write command. */
if (wait_till_ready(flash))
write_enable(flash);
/* Set up command buffer. */
- flash->command[0] = OPCODE_SE;
+ flash->command[0] = flash->erase_opcode;
flash->command[1] = offset >> 16;
flash->command[2] = offset >> 8;
flash->command[3] = offset;
mutex_lock(&flash->lock);
+ /* REVISIT in some cases we could speed up erasing large regions
+ * by using OPCODE_SE instead of OPCODE_BE_4K
+ */
+
/* now erase those sectors */
while (len) {
if (erase_sector(flash, addr)) {
return 1;
}
- /* NOTE: OPCODE_FAST_READ (if available) is faster... */
+ /* FIXME switch to OPCODE_FAST_READ. It's required for higher
+ * clocks; and at this writing, every chip this driver handles
+ * supports that opcode.
+ */
/* Set up the write data buffer. */
flash->command[0] = OPCODE_READ;
struct flash_info {
char *name;
- u8 id;
- u16 jedec_id;
+
+ /* JEDEC id zero means "no ID" (most older chips); otherwise it has
+ * a high byte of zero plus three data bytes: the manufacturer id,
+ * then a two byte device id.
+ */
+ u32 jedec_id;
+
+ /* The size listed here is what works with OPCODE_SE, which isn't
+ * necessarily called a "sector" by the vendor.
+ */
unsigned sector_size;
- unsigned n_sectors;
+ u16 n_sectors;
+
+ u16 flags;
+#define SECT_4K 0x01 /* OPCODE_BE_4K works uniformly */
};
+
+/* NOTE: double check command sets and memory organization when you add
+ * more flash chips. This current list focusses on newer chips, which
+ * have been converging on command sets which including JEDEC ID.
+ */
static struct flash_info __devinitdata m25p_data [] = {
- /* JEDEC id zero means "has no ID" */
- { "m25p05", 0x05, 0x2010, 32 * 1024, 2 },
- { "m25p10", 0x10, 0x2011, 32 * 1024, 4 },
- { "m25p20", 0x11, 0x2012, 64 * 1024, 4 },
- { "m25p40", 0x12, 0x2013, 64 * 1024, 8 },
- { "m25p80", 0x13, 0x0000, 64 * 1024, 16 },
- { "m25p16", 0x14, 0x2015, 64 * 1024, 32 },
- { "m25p32", 0x15, 0x2016, 64 * 1024, 64 },
- { "m25p64", 0x16, 0x2017, 64 * 1024, 128 },
+
+ /* Atmel -- some are (confusingly) marketed as "DataFlash" */
+ { "at25fs010", 0x1f6601, 32 * 1024, 4, SECT_4K, },
+ { "at25fs040", 0x1f6604, 64 * 1024, 8, SECT_4K, },
+
+ { "at25df041a", 0x1f4401, 64 * 1024, 8, SECT_4K, },
+
+ { "at26f004", 0x1f0400, 64 * 1024, 8, SECT_4K, },
+ { "at26df081a", 0x1f4501, 64 * 1024, 16, SECT_4K, },
+ { "at26df161a", 0x1f4601, 64 * 1024, 32, SECT_4K, },
+ { "at26df321", 0x1f4701, 64 * 1024, 64, SECT_4K, },
+
+ /* Spansion -- single (large) sector size only, at least
+ * for the chips listed here (without boot sectors).
+ */
+ { "s25sl004a", 0x010212, 64 * 1024, 8, },
+ { "s25sl008a", 0x010213, 64 * 1024, 16, },
+ { "s25sl016a", 0x010214, 64 * 1024, 32, },
+ { "s25sl032a", 0x010215, 64 * 1024, 64, },
+ { "s25sl064a", 0x010216, 64 * 1024, 128, },
+
+ /* SST -- large erase sizes are "overlays", "sectors" are 4K */
+ { "sst25vf040b", 0xbf258d, 64 * 1024, 8, SECT_4K, },
+ { "sst25vf080b", 0xbf258e, 64 * 1024, 16, SECT_4K, },
+ { "sst25vf016b", 0xbf2541, 64 * 1024, 32, SECT_4K, },
+ { "sst25vf032b", 0xbf254a, 64 * 1024, 64, SECT_4K, },
+
+ /* ST Microelectronics -- newer production may have feature updates */
+ { "m25p05", 0x202010, 32 * 1024, 2, },
+ { "m25p10", 0x202011, 32 * 1024, 4, },
+ { "m25p20", 0x202012, 64 * 1024, 4, },
+ { "m25p40", 0x202013, 64 * 1024, 8, },
+ { "m25p80", 0, 64 * 1024, 16, },
+ { "m25p16", 0x202015, 64 * 1024, 32, },
+ { "m25p32", 0x202016, 64 * 1024, 64, },
+ { "m25p64", 0x202017, 64 * 1024, 128, },
+ { "m25p128", 0x202018, 256 * 1024, 64, },
+
+ { "m45pe80", 0x204014, 64 * 1024, 16, },
+ { "m45pe16", 0x204015, 64 * 1024, 32, },
+
+ { "m25pe80", 0x208014, 64 * 1024, 16, },
+ { "m25pe16", 0x208015, 64 * 1024, 32, SECT_4K, },
+
+ /* Winbond -- w25x "blocks" are 64K, "sectors" are 4K */
+ { "w25x10", 0xef3011, 64 * 1024, 2, SECT_4K, },
+ { "w25x20", 0xef3012, 64 * 1024, 4, SECT_4K, },
+ { "w25x40", 0xef3013, 64 * 1024, 8, SECT_4K, },
+ { "w25x80", 0xef3014, 64 * 1024, 16, SECT_4K, },
+ { "w25x16", 0xef3015, 64 * 1024, 32, SECT_4K, },
+ { "w25x32", 0xef3016, 64 * 1024, 64, SECT_4K, },
+ { "w25x64", 0xef3017, 64 * 1024, 128, SECT_4K, },
};
+static struct flash_info *__devinit jedec_probe(struct spi_device *spi)
+{
+ int tmp;
+ u8 code = OPCODE_RDID;
+ u8 id[3];
+ u32 jedec;
+ struct flash_info *info;
+
+ /* JEDEC also defines an optional "extended device information"
+ * string for after vendor-specific data, after the three bytes
+ * we use here. Supporting some chips might require using it.
+ */
+ tmp = spi_write_then_read(spi, &code, 1, id, 3);
+ if (tmp < 0) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: error %d reading JEDEC ID\n",
+ spi->dev.bus_id, tmp);
+ return NULL;
+ }
+ jedec = id[0];
+ jedec = jedec << 8;
+ jedec |= id[1];
+ jedec = jedec << 8;
+ jedec |= id[2];
+
+ for (tmp = 0, info = m25p_data;
+ tmp < ARRAY_SIZE(m25p_data);
+ tmp++, info++) {
+ if (info->jedec_id == jedec)
+ return info;
+ }
+ dev_err(&spi->dev, "unrecognized JEDEC id %06x\n", jedec);
+ return NULL;
+}
+
+
/*
* board specific setup should have ensured the SPI clock used here
* matches what the READ command supports, at least until this driver
unsigned i;
/* Platform data helps sort out which chip type we have, as
- * well as how this board partitions it.
+ * well as how this board partitions it. If we don't have
+ * a chip ID, try the JEDEC id commands; they'll work for most
+ * newer chips, even if we don't recognize the particular chip.
*/
data = spi->dev.platform_data;
- if (!data || !data->type) {
- /* FIXME some chips can identify themselves with RES
- * or JEDEC get-id commands. Try them ...
- */
- DEBUG(MTD_DEBUG_LEVEL1, "%s: no chip id\n",
- spi->dev.bus_id);
- return -ENODEV;
- }
+ if (data && data->type) {
+ for (i = 0, info = m25p_data;
+ i < ARRAY_SIZE(m25p_data);
+ i++, info++) {
+ if (strcmp(data->type, info->name) == 0)
+ break;
+ }
- for (i = 0, info = m25p_data; i < ARRAY_SIZE(m25p_data); i++, info++) {
- if (strcmp(data->type, info->name) == 0)
- break;
- }
- if (i == ARRAY_SIZE(m25p_data)) {
- DEBUG(MTD_DEBUG_LEVEL1, "%s: unrecognized id %s\n",
- spi->dev.bus_id, data->type);
+ /* unrecognized chip? */
+ if (i == ARRAY_SIZE(m25p_data)) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: unrecognized id %s\n",
+ spi->dev.bus_id, data->type);
+ info = NULL;
+
+ /* recognized; is that chip really what's there? */
+ } else if (info->jedec_id) {
+ struct flash_info *chip = jedec_probe(spi);
+
+ if (!chip || chip != info) {
+ dev_warn(&spi->dev, "found %s, expected %s\n",
+ chip ? chip->name : "UNKNOWN",
+ info->name);
+ info = NULL;
+ }
+ }
+ } else
+ info = jedec_probe(spi);
+
+ if (!info)
return -ENODEV;
- }
flash = kzalloc(sizeof *flash, GFP_KERNEL);
if (!flash)
mutex_init(&flash->lock);
dev_set_drvdata(&spi->dev, flash);
- if (data->name)
+ if (data && data->name)
flash->mtd.name = data->name;
else
flash->mtd.name = spi->dev.bus_id;
flash->mtd.writesize = 1;
flash->mtd.flags = MTD_CAP_NORFLASH;
flash->mtd.size = info->sector_size * info->n_sectors;
- flash->mtd.erasesize = info->sector_size;
flash->mtd.erase = m25p80_erase;
flash->mtd.read = m25p80_read;
flash->mtd.write = m25p80_write;
+ /* prefer "small sector" erase if possible */
+ if (info->flags & SECT_4K) {
+ flash->erase_opcode = OPCODE_BE_4K;
+ flash->mtd.erasesize = 4096;
+ } else {
+ flash->erase_opcode = OPCODE_SE;
+ flash->mtd.erasesize = info->sector_size;
+ }
+
dev_info(&spi->dev, "%s (%d Kbytes)\n", info->name,
flash->mtd.size / 1024);
}
if (nr_parts > 0) {
- for (i = 0; i < data->nr_parts; i++) {
+ for (i = 0; i < nr_parts; i++) {
DEBUG(MTD_DEBUG_LEVEL2, "partitions[%d] = "
"{.name = %s, .offset = 0x%.8x, "
".size = 0x%.8x (%uK) }\n",
- i, data->parts[i].name,
- data->parts[i].offset,
- data->parts[i].size,
- data->parts[i].size / 1024);
+ i, parts[i].name,
+ parts[i].offset,
+ parts[i].size,
+ parts[i].size / 1024);
}
flash->partitioned = 1;
return add_mtd_partitions(&flash->mtd, parts, nr_parts);
},
.probe = m25p_probe,
.remove = __devexit_p(m25p_remove),
+
+ /* REVISIT: many of these chips have deep power-down modes, which
+ * should clearly be entered on suspend() to minimize power use.
+ * And also when they're otherwise idle...
+ */
};
projects / linux-beck.git / commitdiff