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 <[email protected]> > --- > 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/[email protected]/ > > --- > 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)
