[U-Boot] [PATCH v3 05/17] sf: read flash bank addr register at probe time

[Simon Glass]

On Tue, Jun 11, 2013 at 12:23 PM, Jagannadha Sutradharudu Teki <
jagannadha.sutradharudu-teki at xilinx.com> wrote:

> 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 at xilinx.com>
>

Reviewed-by: Simon Glass <sjg at chromium.org>


> ---
> Changes for v3:
>         - none
> 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,
> --
> 1.8.3
>
>
>