+++ /dev/null
-mtd: spi-nor: add support for switching between 3-byte and 4-byte addressing on w25q256 flash
-
-On some devices the flash chip needs to be in 3-byte addressing mode during
-reboot, otherwise the boot loader will fail to start.
-This mode however does not allow regular reads/writes onto the upper 16M
-half. W25Q256 has separate read commands for reading from >16M, however
-it does not have any separate write commands.
-This patch changes the code to leave the chip in 3-byte mode most of the
-time and only switch during erase/write cycles that go to >16M
-addresses.
-
-Signed-off-by: Felix Fietkau <nbd@nbd.name>
----
---- a/drivers/mtd/spi-nor/spi-nor.c
-+++ b/drivers/mtd/spi-nor/spi-nor.c
-@@ -89,6 +89,10 @@ struct flash_info {
- #define NO_CHIP_ERASE BIT(12) /* Chip does not support chip erase */
- #define SPI_NOR_SKIP_SFDP BIT(13) /* Skip parsing of SFDP tables */
- #define USE_CLSR BIT(14) /* use CLSR command */
-+#define SPI_NOR_4B_READ_OP BIT(15) /*
-+ * Like SPI_NOR_4B_OPCODES, but for read
-+ * op code only.
-+ */
- };
-
- #define JEDEC_MFR(info) ((info)->id[0])
-@@ -240,6 +244,15 @@ static inline u8 spi_nor_convert_3to4_er
- ARRAY_SIZE(spi_nor_3to4_erase));
- }
-
-+static void spi_nor_set_4byte_read(struct spi_nor *nor,
-+ const struct flash_info *info)
-+{
-+ nor->addr_width = 3;
-+ nor->ext_addr = 0;
-+ nor->read_opcode = spi_nor_convert_3to4_read(nor->read_opcode);
-+ nor->flags |= SNOR_F_4B_EXT_ADDR;
-+}
-+
- static void spi_nor_set_4byte_opcodes(struct spi_nor *nor,
- const struct flash_info *info)
- {
-@@ -467,6 +480,36 @@ static int spi_nor_erase_sector(struct s
- return nor->write_reg(nor, nor->erase_opcode, buf, nor->addr_width);
- }
-
-+static int spi_nor_check_ext_addr(struct spi_nor *nor, u32 addr)
-+{
-+ bool ext_addr;
-+ int ret;
-+ u8 cmd;
-+
-+ if (!(nor->flags & SNOR_F_4B_EXT_ADDR))
-+ return 0;
-+
-+ ext_addr = !!(addr & 0xff000000);
-+ if (nor->ext_addr == ext_addr)
-+ return 0;
-+
-+ cmd = ext_addr ? SPINOR_OP_EN4B : SPINOR_OP_EX4B;
-+ write_enable(nor);
-+ ret = nor->write_reg(nor, cmd, NULL, 0);
-+ if (ret)
-+ return ret;
-+
-+ cmd = 0;
-+ ret = nor->write_reg(nor, SPINOR_OP_WREAR, &cmd, 1);
-+ if (ret)
-+ return ret;
-+
-+ nor->addr_width = 3 + ext_addr;
-+ nor->ext_addr = ext_addr;
-+ write_disable(nor);
-+ return 0;
-+}
-+
- /*
- * Erase an address range on the nor chip. The address range may extend
- * one or more erase sectors. Return an error is there is a problem erasing.
-@@ -492,6 +535,10 @@ static int spi_nor_erase(struct mtd_info
- if (ret)
- return ret;
-
-+ ret = spi_nor_check_ext_addr(nor, addr + len);
-+ if (ret)
-+ return ret;
-+
- /* whole-chip erase? */
- if (len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) {
- unsigned long timeout;
-@@ -542,6 +589,7 @@ static int spi_nor_erase(struct mtd_info
- write_disable(nor);
-
- erase_err:
-+ spi_nor_check_ext_addr(nor, 0);
- spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_ERASE);
-
- instr->state = ret ? MTD_ERASE_FAILED : MTD_ERASE_DONE;
-@@ -834,7 +882,9 @@ static int spi_nor_lock(struct mtd_info
- if (ret)
- return ret;
-
-+ spi_nor_check_ext_addr(nor, ofs + len);
- ret = nor->flash_lock(nor, ofs, len);
-+ spi_nor_check_ext_addr(nor, 0);
-
- spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_UNLOCK);
- return ret;
-@@ -849,7 +899,9 @@ static int spi_nor_unlock(struct mtd_inf
- if (ret)
- return ret;
-
-+ spi_nor_check_ext_addr(nor, ofs + len);
- ret = nor->flash_unlock(nor, ofs, len);
-+ spi_nor_check_ext_addr(nor, 0);
-
- spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_LOCK);
- return ret;
-@@ -1182,7 +1234,7 @@ static const struct flash_info spi_nor_i
- { "w25q80", INFO(0xef5014, 0, 64 * 1024, 16, SECT_4K) },
- { "w25q80bl", INFO(0xef4014, 0, 64 * 1024, 16, SECT_4K) },
- { "w25q128", INFO(0xef4018, 0, 64 * 1024, 256, SECT_4K) },
-- { "w25q256", INFO(0xef4019, 0, 64 * 1024, 512, SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
-+ { "w25q256", INFO(0xef4019, 0, 64 * 1024, 512, SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | SPI_NOR_4B_READ_OP) },
- { "w25m512jv", INFO(0xef7119, 0, 64 * 1024, 1024,
- SECT_4K | SPI_NOR_QUAD_READ | SPI_NOR_DUAL_READ) },
-
-@@ -1245,6 +1297,9 @@ static int spi_nor_read(struct mtd_info
- if (ret)
- return ret;
-
-+ if (nor->flags & SNOR_F_4B_EXT_ADDR)
-+ nor->addr_width = 4;
-+
- while (len) {
- loff_t addr = from;
-
-@@ -1269,6 +1324,18 @@ static int spi_nor_read(struct mtd_info
- ret = 0;
-
- read_err:
-+ if (nor->flags & SNOR_F_4B_EXT_ADDR) {
-+ u8 val = 0;
-+
-+ if ((from + len) & 0xff000000) {
-+ write_enable(nor);
-+ nor->write_reg(nor, SPINOR_OP_WREAR, &val, 1);
-+ write_disable(nor);
-+ }
-+
-+ nor->addr_width = 3;
-+ }
-+
- spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_READ);
- return ret;
- }
-@@ -1370,6 +1437,10 @@ static int spi_nor_write(struct mtd_info
- if (ret)
- return ret;
-
-+ ret = spi_nor_check_ext_addr(nor, to + len);
-+ if (ret < 0)
-+ return ret;
-+
- for (i = 0; i < len; ) {
- ssize_t written;
- loff_t addr = to + i;
-@@ -1410,6 +1481,7 @@ static int spi_nor_write(struct mtd_info
- }
-
- write_err:
-+ spi_nor_check_ext_addr(nor, 0);
- spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_WRITE);
- return ret;
- }
-@@ -2826,8 +2898,10 @@ int spi_nor_scan(struct spi_nor *nor, co
- } else if (mtd->size > 0x1000000) {
- /* enable 4-byte addressing if the device exceeds 16MiB */
- nor->addr_width = 4;
-- if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
-- info->flags & SPI_NOR_4B_OPCODES)
-+ if (info->flags & SPI_NOR_4B_READ_OP)
-+ spi_nor_set_4byte_read(nor, info);
-+ else if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
-+ info->flags & SPI_NOR_4B_OPCODES)
- spi_nor_set_4byte_opcodes(nor, info);
- else
- set_4byte(nor, info, 1);
---- a/include/linux/mtd/spi-nor.h
-+++ b/include/linux/mtd/spi-nor.h
-@@ -102,6 +102,7 @@
- /* Used for Macronix and Winbond flashes. */
- #define SPINOR_OP_EN4B 0xb7 /* Enter 4-byte mode */
- #define SPINOR_OP_EX4B 0xe9 /* Exit 4-byte mode */
-+#define SPINOR_OP_WREAR 0xc5 /* Write extended address register */
-
- /* Used for Spansion flashes only. */
- #define SPINOR_OP_BRWR 0x17 /* Bank register write */
-@@ -229,6 +230,7 @@ enum spi_nor_option_flags {
- SNOR_F_S3AN_ADDR_DEFAULT = BIT(3),
- SNOR_F_READY_XSR_RDY = BIT(4),
- SNOR_F_USE_CLSR = BIT(5),
-+ SNOR_F_4B_EXT_ADDR = BIT(6),
- };
-
- /**
-@@ -280,6 +282,7 @@ struct spi_nor {
- enum spi_nor_protocol reg_proto;
- bool sst_write_second;
- u32 flags;
-+ u8 ext_addr;
- u8 cmd_buf[SPI_NOR_MAX_CMD_SIZE];
-
- int (*prepare)(struct spi_nor *nor, enum spi_nor_ops ops);
projects / openwrt / openwrt.git / blobdiff