[PATCH v2 0/6] arm: snapdragon: Add snagboot support for Lemans-EVK

[Casey Connolly]

Hi Balaji,

On 08/06/2026 11:06, Balaji Selvanathan wrote:
> This series adds support for running U-Boot in snagboot mode on
> Qualcomm Snapdragon platforms, targeting the Lemans-EVK board.
> 
> In snagboot mode, XBL loads U-Boot directly without initializing
> PSCI firmware or populating the Command DB. U-Boot then enters
> fastboot immediately, enabling partition flashing for manufacturing
> and recovery use cases.

Is this for building a firehose binary with U-Boot? Some additional
explanation of what this is and why/how it should be used would be good.

Kind regards,

> 
> Patch 1 changes SYSRESET_PSCI from 'select' to 'imply' so it can
> be disabled on platforms where PSCI firmware is unavailable.
> 
> Patch 2 guards show_psci_version() and qcom_psci_fixup() with
> CONFIG_ARM_SMCCC to prevent build failures when SMCCC is disabled.
> 
> Patch 3 disables the MMU and invalidates TLBs at the earliest entry
> point to clear stale page tables left by previous bootloader
> before U-Boot sets up its own MMU.
> 
> Patch 4 adds QCOM_COMMAND_DB_OPTIONAL to allow the CMD DB driver to
> bind successfully when CMD DB data is not populated by XBL, logging
> a warning instead of failing.
> 
> Patch 5 adds qcom_lemans_snagboot_defconfig for Lemans-EVK, based
> on qcom_defconfig with snagboot-specific settings: SCSI-backed
> environment, optional CMD DB, PSCI reset disabled, and a bootcmd
> that auto-enters fastboot over USB with zero boot delay.
> 
> Patch 6 adds the new defconfig to the ARM SNAPDRAGON section in
> MAINTAINERS.
> 
> Signed-off-by: Balaji Selvanathan <balaji.selvanathan at oss.qualcomm.com>
> ---
> Changes in v2:
> - Changed SYSRESET_PSCI from 'select' to 'imply'
> - Guard show_psci_version() and qcom_psci_fixup() with CONFIG_ARM_SMCCC
> - Disables the MMU and invalidates TLBs at the earliest entry point
> - Add qcom_lemans_snagboot_defconfig for Lemans-EVK
> - Link to v1: https://lore.kernel.org/u-boot/20260409-cmddb-v1-1-b10549b34133@oss.qualcomm.com/
> 
> ---
> Balaji Selvanathan (6):
>       arm: snapdragon: Make SYSRESET_PSCI optional
>       arm: snapdragon: Guard PSCI functions with CONFIG_ARM_SMCCC
>       arm: snapdragon: Disable MMU early before U-Boot reset vector
>       soc: qcom: cmd-db: Allow boot without CMD DB data
>       configs: add qcom_lemans_snagboot_defconfig for Lemans-EVK
>       MAINTAINERS: add qcom_lemans_snagboot_defconfig to ARM SNAPDRAGON
> 
>  MAINTAINERS                                   |  1 +
>  arch/arm/Kconfig                              |  2 +-
>  arch/arm/mach-snapdragon/board.c              | 14 ++++++++
>  arch/arm/mach-snapdragon/include/mach/boot0.h | 46 +++++++++++++++++++++++++
>  configs/qcom_lemans_snagboot_defconfig        | 49 +++++++++++++++++++++++++++
>  drivers/soc/qcom/Kconfig                      | 16 +++++++++
>  drivers/soc/qcom/cmd-db.c                     | 10 ++++++
>  7 files changed, 137 insertions(+), 1 deletion(-)
> ---
> base-commit: 26fe27b4eaddcf73e4472368a71703a68e2f67d9
> change-id: 20260608-snagboot-df4b6a79a086
> 
> Best regards,

-- 
// Casey (she/her)