Re: [PATCH 2/2] [v2] qcom_scm: hide Kconfig symbol

Alex Elder
2021-09-28T13:29:48Z

On 9/28/21 2:50 AM, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> Now that SCM can be a loadable module, we have to add another
> dependency to avoid link failures when ipa or adreno-gpu are
> built-in:
>
> aarch64-linux-ld: drivers/net/ipa/ipa_main.o: in function `ipa_probe':
> ipa_main.c:(.text+0xfc4): undefined reference to `qcom_scm_is_available'
>
> ld.lld: error: undefined symbol: qcom_scm_is_available
>>>> referenced by adreno_gpu.c
>>>> gpu/drm/msm/adreno/adreno_gpu.o:(adreno_zap_shader_load) in archive drivers/built-in.a
>
> This can happen when CONFIG_ARCH_QCOM is disabled and we don't select
> QCOM_MDT_LOADER, but some other module selects QCOM_SCM. Ideally we'd
> use a similar dependency here to what we have for QCOM_RPROC_COMMON,
> but that causes dependency loops from other things selecting QCOM_SCM.
>
> This appears to be an endless problem, so try something different this
> time:
>
> - CONFIG_QCOM_SCM becomes a hidden symbol that nothing 'depends on'
> but that is simply selected by all of its users
>
> - All the stubs in include/linux/qcom_scm.h can go away
>
> - arm-smccc.h needs to provide a stub for __arm_smccc_smc() to
> allow compile-testing QCOM_SCM on all architectures.
>
> - To avoid a circular dependency chain involving RESET_CONTROLLER
> and PINCTRL_SUNXI, drop the 'select RESET_CONTROLLER' statement.
> According to my testing this still builds fine, and the QCOM
> platform selects this symbol already.
>
> Acked-by: Kalle Valo <kvalo@codeaurora.org>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> Changes in v2:
> - drop the 'select RESET_CONTROLLER' line, rather than adding
> more of the same
> ---
> drivers/firmware/Kconfig | 5 +-
> drivers/gpu/drm/msm/Kconfig | 4 +-
> drivers/iommu/Kconfig | 2 +-
> drivers/media/platform/Kconfig | 2 +-
> drivers/mmc/host/Kconfig | 2 +-
> drivers/net/ipa/Kconfig | 1 +

For drivers/net/ipa/Kconfig, looks good to me.
Nice simplification.

Acked-by: Alex Elder <elder@linaro.org>

> drivers/net/wireless/ath/ath10k/Kconfig | 2 +-
> drivers/pinctrl/qcom/Kconfig | 3 +-
> include/linux/arm-smccc.h | 10 ++++
> include/linux/qcom_scm.h | 71 -------------------------
> 10 files changed, 20 insertions(+), 82 deletions(-)
>

. . .