Re: [PATCH v3 6/6] firmware: qcom: Add support for TEE based EFI-var client driver

[Krzysztof Kozlowski <krzk@kernel.org>]

On 01/10/2026 13:02, Harshal Dev wrote:
> On Qualcomm SoC based platforms, UEFI stores EFI variables within the
> Replay Protected Memory Block (RPMB) located within either the UFS,
> eMMC or SPI-NOR storage. The RPMB key which is one-time programmed into
> the storage controller to allow authentication of the RPMB frames is
> generated by and only available to the Qualcomm Trusted Execution
> Environment (QTEE).
> 
> The legacy QSEECOM protocol used for communicating with the QTEE is
> deprecated and replaced with the use-case agnostic SMCInvoke protocol
> starting with the Qualcomm SM8x50 series. On platforms where the QSEECOM
> still driver probes, it does not support a listener interface with QTEE
> to enable writing of non-volatile EFI variables to the RPMB for UFS and
> eMMC storage.
> Therefore on such platforms, a TEE client driver which communicates with
> QTEE via the SMCInvoke protocol implemented by the QCOMTEE driver (and
> registered with the TEE subsystem) must be used to update such EFI
> variables.
> 
> Add support for a TEE based uefisecapp client driver which installs efivar
> operations after obtaining an object reference to the uefisecapp service.
> This enables the kernel/user-space to access or modify both volatile EFI
> variables stored by the Secure Application (in-memory) and non-volatile
> ones stored within RPMB.
> 
> Signed-off-by: Harshal Dev <harshal.dev@oss.qualcomm.com>
> ---
>  MAINTAINERS                                 |   6 +
>  arch/arm64/configs/defconfig                |   1 +
>  drivers/firmware/qcom/Kconfig               |  31 ++
>  drivers/firmware/qcom/Makefile              |   1 +
>  drivers/firmware/qcom/qcom_tee_uefisecapp.c | 636 ++++++++++++++++++++++++++++
>  5 files changed, 675 insertions(+)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 30c1cdd0fb38..7ccedad8d388 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -22981,6 +22981,12 @@ L:	linux-arm-msm@vger.kernel.org
>  S:	Maintained
>  F:	drivers/firmware/qcom/qcom_qseecom_uefisecapp.c
>  
> +QUALCOMM TEE UEFISECAPP DRIVER
> +M:	Harshal Dev <harshal.dev@oss.qualcomm.com>
> +L:	linux-arm-msm@vger.kernel.org
> +S:	Maintained
> +F:	drivers/firmware/qcom/qcom_tee_uefisecapp.c
> +
>  QUALCOMM PINCTRL DRIVERS
>  M:	Bartosz Golaszewski <brgl@kernel.org>
>  L:	linux-arm-msm@vger.kernel.org
> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
> index fce418fe6ff6..a8525878c679 100644
> --- a/arch/arm64/configs/defconfig
> +++ b/arch/arm64/configs/defconfig
> @@ -277,6 +277,7 @@ CONFIG_IMX_SCU=y
>  CONFIG_QCOM_TZMEM_MODE_SHMBRIDGE=y
>  CONFIG_QCOM_QSEECOM=y
>  CONFIG_QCOM_QSEECOM_UEFISECAPP=y
> +CONFIG_QCOM_TEE_UEFISECAPP=m

I do not see how this change is relevant here. Adding a driver has
nothing to do with defconfig. Drop or split.

Not mentioning that nowhere is explained why you actually need it.


Best regards,
Krzysztof