Re: [PATCH 3/3] x86: emulation: enable cfi flash drivers

Hi Elliot,

On 2026-07-30T19:37:45, Elliot Berman <[email protected]> wrote:
> x86: emulation: enable cfi flash drivers
>
> Enable MTD/CFI so the pflash node just added for qemu-x86/qemu-x86_64
> can be probed, matching the flash config qemu_arm64_defconfig.
>
> Signed-off-by: Elliot Berman <[email protected]>
>
> configs/qemu-x86_64_defconfig | 13 +++++++++++++
>  configs/qemu-x86_defconfig    | 13 +++++++++++++
>  2 files changed, 26 insertions(+)

> diff --git a/configs/qemu-x86_64_defconfig b/configs/qemu-x86_64_defconfig
> @@ -76,6 +79,16 @@ CONFIG_ATAPI=y
>  CONFIG_LBA48=y
>  CONFIG_SYS_64BIT_LBA=y
>  CONFIG_CPU=y
> +CONFIG_DFU_MTD=y
> +CONFIG_DM_MTD=y
> +CONFIG_MTD_NOR_FLASH=y
> +CONFIG_CFI_FLASH=y
> +CONFIG_SYS_FLASH_USE_BUFFER_WRITE=y
> +CONFIG_FLASH_CFI_MTD=y
> +CONFIG_SYS_FLASH_CFI=y
> +CONFIG_SYS_MAX_FLASH_SECT=1024
> +CONFIG_SYS_MAX_FLASH_BANKS=2
> +CONFIG_SYS_MAX_FLASH_BANKS_DETECT=y

CONFIG_SYS_FLASH_CFI is only referenced by a handful of legacy m68k
board headers - it has no effect for a DM CFI-flash setup, so please
drop it. qemu_arm64_defconfig doesn't set it either.

> diff --git a/configs/qemu-x86_64_defconfig b/configs/qemu-x86_64_defconfig
> @@ -76,6 +79,16 @@ CONFIG_ATAPI=y
> +CONFIG_SYS_FLASH_USE_BUFFER_WRITE=y

qemu_arm64_defconfig doesn't enable this and the emulated CFI pflash
handles single-word writes fine. Please drop it too so the two
defconfigs really do match.

> diff --git a/configs/qemu-x86_64_defconfig b/configs/qemu-x86_64_defconfig
> @@ -48,7 +48,9 @@ CONFIG_CMD_CPU=y
>  CONFIG_CMD_BOOTEFI_SELFTEST=y
>  CONFIG_CMD_NVEDIT_EFY=y
>  CONFIG_CMD_MEM_SEARCH=y
> +CONFIG_CMD_DFU=y
>  CONFIG_CMD_IDE=y
> +CONFIG_CMD_MTD=y

The commit message says this enables MTD/CFI so the pflash node can be
probed, but you are also turning on DFU, MTD and MTDPARTS commands
plus DFU_MTD, which exist to make patch 2's capsule wiring work.
Please either update the commit message to describe the full scope, or
split the DFU/MTDPARTS bits out.

Regards,
Simon