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

Hi Simon,

On Mon, Aug 03, 2026 at 01:25:36PM -0600, Simon Glass wrote:
> 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.

qemu_arm64_defconfig has SYS_FLASH_USE_BUFFER_WRITE and SYS_FLASH_CFI
enabled [1]. However, I agree that neither of these are needed for the
x86 defconfigs. I'll drop them in v2.

[1]: https://git.u-boot-project.org/u-boot/u-boot/-/blob/main/configs/qemu_arm64_defconfig#L56-58

> > 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