[U-Boot-Users] [PATCH] CFI: synchronize command offsets with Linux CFI driver

[Stefan Roese]

On Tuesday 11 December 2007, Bartlomiej Sieka wrote:
> Fixes non-working CFI Flash on the Inka4x0 board.
>
> Signed-off-by: Bartlomiej Sieka <tur at semihalf.com>
> ---
> This patch differs from what is being done by the Linux CFI driver in that
> it uses 0x05 as the interface code for x16/x32 chips, per "Common Flash
> Memory Interface Publication 100" dated December 1.
>
> Tested on the following Flash chips:
> x8 (interface 0x00) in 8 bit mode
> x8/x16 (interface 0x02) in 8 bit mode
> x8/x16 (interface 0x02) in 16 bit mode
>
> The patch should be applied on top of commit
> 81b20ccc2d795ae9a1199db5a50ad9c28d1e4d22 in the u-boot-cfi-flash repo.
>
> diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
> index 66754cd..b748a9f 100644
> --- a/drivers/mtd/cfi_flash.c
> +++ b/drivers/mtd/cfi_flash.c
> @@ -1231,9 +1231,26 @@ static int flash_detect_cfi (flash_info_t * info)
>  					debug ("port %d bits chip %d bits\n",
>  						info->portwidth << CFI_FLASH_SHIFT_WIDTH,
>  						info->chipwidth << CFI_FLASH_SHIFT_WIDTH);
> -					/* this probably only works if info->interface == FLASH_CFI_X8X16 */
> -					info->addr_unlock1 = (info->portwidth == FLASH_CFI_8BIT) ? 0xAAA :
> 0x555; -					info->addr_unlock2 = (info->portwidth == FLASH_CFI_8BIT) ?
> 0x555 : 0x2AA; +
> +					/* calculate command offsets as in the Linux driver */
> +					info->addr_unlock1 = 0x555;
> +					info->addr_unlock2 = 0x2aa;
> +
> +					/*
> +					 * modify the unlock address if we are
> +					 * in compatibility mode
> +					 */
> +					if (	/* x8/x16 in x8 mode */
> +						((info->chipwidth == FLASH_CFI_BY8) &&
> +							(info->interface == FLASH_CFI_X8X16)) ||
> +						/* x16/x32 in x16 mode */
> +						((info->chipwidth == FLASH_CFI_BY16) &&
> +							(info->interface == FLASH_CFI_X16X32)))
> +					{
> +						info->addr_unlock1 = 0xaaa;
> +						info->addr_unlock2 = 0x555;
> +					}
> +

Why not like this:

					if (((info->chipwidth == FLASH_CFI_BY8) &&
					     (info->interface == FLASH_CFI_X8X16)) ||
					    ((info->chipwidth == FLASH_CFI_BY16) &&
					     (info->interface == FLASH_CFI_X16X32))) {
						/*
						 * Compatibility mode:
						 * x8/x16 in x8 mode or
						 * x16/x32 in x16 mode
						 */
						info->addr_unlock1 = 0xaaa;
						info->addr_unlock2 = 0x555;
					} else {
						/* default */
						info->addr_unlock1 = 0x555;
						info->addr_unlock2 = 0x2aa;
					}


Thanks.

Best regards,
Stefan

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