Read the flash bank addr register to get the state of bank in a perticular flash. and also bank write happens only when there is a change in bank selection from user.
bank read only valid for flashes which has > 16Mbytes those are opearted in 3-byte addr mode, each bank occupies 16Mytes.
Suppose if the flash has 64Mbytes size consists of 4 banks like bank0, bank1, bank2 and bank3.
Signed-off-by: Jagannadha Sutradharudu Teki jaganna@xilinx.com --- Changes for v2: - none
drivers/mtd/spi/spi_flash.c | 17 +++++++++++++++++ drivers/mtd/spi/spi_flash_internal.h | 2 ++ include/spi_flash.h | 2 ++ 3 files changed, 21 insertions(+)
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c index 66b6b14..4576a16 100644 --- a/drivers/mtd/spi/spi_flash.c +++ b/drivers/mtd/spi/spi_flash.c @@ -283,6 +283,11 @@ int spi_flash_cmd_bankaddr_write(struct spi_flash *flash, u8 bank_sel) u8 cmd, idcode0; int ret;
+ if (flash->bank_curr == bank_sel) { + debug("SF: not require to enable bank%d\n", bank_sel); + return 0; + } + idcode0 = flash->idcode0; if (idcode0 == 0x01) { cmd = CMD_BANKADDR_BRWR; @@ -304,6 +309,7 @@ int spi_flash_cmd_bankaddr_write(struct spi_flash *flash, u8 bank_sel) debug("SF: fail to write bank addr register\n"); return ret; } + flash->bank_curr = bank_sel;
ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT); if (ret < 0) { @@ -432,6 +438,7 @@ struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs, struct spi_flash *flash = NULL; int ret, i, shift; u8 idcode[IDCODE_LEN], *idp; + u8 curr_bank = 0;
spi = spi_setup_slave(bus, cs, max_hz, spi_mode); if (!spi) { @@ -491,6 +498,16 @@ struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs, printf(", mapped at %p", flash->memory_map); puts("\n");
+ if (flash->size > SPI_FLASH_16MB_BOUN) { + if (spi_flash_cmd_bankaddr_read(flash, &curr_bank)) { + debug("SF: fail to read bank addr register\n"); + goto err_manufacturer_probe; + } + flash->bank_curr = curr_bank; + } else { + flash->bank_curr = curr_bank; + } + spi_release_bus(spi);
return flash; diff --git a/drivers/mtd/spi/spi_flash_internal.h b/drivers/mtd/spi/spi_flash_internal.h index 1b29e2d..455dc02 100644 --- a/drivers/mtd/spi/spi_flash_internal.h +++ b/drivers/mtd/spi/spi_flash_internal.h @@ -12,6 +12,8 @@ #define SPI_FLASH_PAGE_ERASE_TIMEOUT (5 * CONFIG_SYS_HZ) #define SPI_FLASH_SECTOR_ERASE_TIMEOUT (10 * CONFIG_SYS_HZ)
+#define SPI_FLASH_16MB_BOUN 0x1000000 + /* Common commands */ #define CMD_READ_ID 0x9f
diff --git a/include/spi_flash.h b/include/spi_flash.h index 5ea42e1..acac17a 100644 --- a/include/spi_flash.h +++ b/include/spi_flash.h @@ -40,6 +40,8 @@ struct spi_flash { u32 sector_size; /* ID code0 */ u8 idcode0; + /* Current flash bank */ + u8 bank_curr;
void *memory_map; /* Address of read-only SPI flash access */ int (*read)(struct spi_flash *flash, u32 offset,