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 Reviewed-by: Simon Glass sjg@chromium.org --- Changes for v5: - bank_read_cmd <= bank_cmd[0] - bank_write_cmd <= bank_cmd[1] Changes for v4: - Added spi_flash_bank_config Changes for v3: - none Changes for v2: - none
drivers/mtd/spi/spi_flash.c | 27 +++++++++++++++++++++++++++ drivers/mtd/spi/spi_flash_internal.h | 2 ++ include/spi_flash.h | 2 ++ 3 files changed, 31 insertions(+)
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c index 7e19953..64b57ec 100644 --- a/drivers/mtd/spi/spi_flash.c +++ b/drivers/mtd/spi/spi_flash.c @@ -283,6 +283,12 @@ int spi_flash_cmd_bankaddr_write(struct spi_flash *flash, u8 bank_sel) u8 cmd; int ret;
+ if (flash->bank_curr == bank_sel) { + debug("SF: not require to enable bank%d\n", bank_sel); + return 0; + } + + cmd = flash->bank_write_cmd; ret = spi_flash_cmd_write_enable(flash); if (ret < 0) { debug("SF: enabling write failed\n"); @@ -294,6 +300,7 @@ 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) { @@ -306,6 +313,9 @@ int spi_flash_cmd_bankaddr_write(struct spi_flash *flash, u8 bank_sel)
int spi_flash_bank_config(struct spi_flash *flash, u8 idcode0) { + u8 cmd; + u8 curr_bank = 0; + /* discover bank cmds */ switch (idcode0) { case SPI_FLASH_SPANSION_IDCODE0: @@ -322,6 +332,18 @@ int spi_flash_bank_config(struct spi_flash *flash, u8 idcode0) return -1; }
+ /* read the bank reg - on which bank the flash is in currently */ + cmd = flash->bank_read_cmd; + if (flash->size > SPI_FLASH_16MB_BOUN) { + if (spi_flash_read_common(flash, &cmd, 1, &curr_bank, 1)) { + debug("SF: fail to read bank addr register\n"); + return -1; + } + flash->bank_curr = curr_bank; + } else { + flash->bank_curr = curr_bank; + } + return 0; }
@@ -469,6 +491,11 @@ struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs, goto err_manufacturer_probe; }
+ /* Configure the BAR - disover bank cmds and read current bank */ + ret = spi_flash_bank_config(flash, *idp); + if (ret < 0) + goto err_manufacturer_probe; + #ifdef CONFIG_OF_CONTROL if (spi_flash_decode_fdt(gd->fdt_blob, flash)) { debug("SF: FDT decode error\n"); diff --git a/drivers/mtd/spi/spi_flash_internal.h b/drivers/mtd/spi/spi_flash_internal.h index db6c444..00ed1ee 100644 --- a/drivers/mtd/spi/spi_flash_internal.h +++ b/drivers/mtd/spi/spi_flash_internal.h @@ -28,6 +28,8 @@ #define CMD_ERASE_64K 0xd8 #define CMD_ERASE_CHIP 0xc7
+#define SPI_FLASH_16MB_BOUN 0x1000000 + /* Manufacture ID's */ #define SPI_FLASH_SPANSION_IDCODE0 0x01 #define SPI_FLASH_STMICRO_IDCODE0 0x20 diff --git a/include/spi_flash.h b/include/spi_flash.h index 38587c2..91b43ee 100644 --- a/include/spi_flash.h +++ b/include/spi_flash.h @@ -42,6 +42,8 @@ struct spi_flash { u8 bank_read_cmd; /* Bank write cmd */ u8 bank_write_cmd; + /* Current flash bank */ + u8 bank_curr;
void *memory_map; /* Address of read-only SPI flash access */ int (*read)(struct spi_flash *flash, u32 offset,