From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alex Elder <elder@ieee.org>
Date: Tue, 28 Sep 2021 13:29:48 +0000
Subject: Re: [PATCH 2/2] [v2] qcom_scm: hide Kconfig symbol
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 <20210928075216.4193128-2-arnd@kernel.org>
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To: Arnd Bergmann <arnd@kernel.org>, Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>, Mark Brown <broonie@kernel.org>, Liam Girdwood <lgirdwood@gmail.com>, Charles Keepax <ckeepax@opensource.cirrus.com>, Simon Trimmer <simont@opensource.cirrus.com>, Michael Ellerman <mpe@ellerman.id.au>, Russell King <linux@armlinux.org.uk>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>, Helge Deller <deller@gmx.de>, Paul Walmsley <paul.walmsley@sifive.com>, Palmer Dabbelt <palmer@dabbelt.com>, Albert Ou <aou@eecs.berkeley.edu>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>, Geert Uytterhoeven <geert+renesas@glider.be>, Linus Walleij <linus.walleij@linaro.org>, Andrew Morton <akpm@linux-foundation.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, Kalle Valo <kvalo@codeaurora.org>, Rob Clark <robdclark@gmail.com>, Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>, Joerg Roedel <joro@8bytes.org>, Mauro Carvalho Chehab <mchehab@kernel.org>, Ulf Hansson <ulf.hansson@linaro.org>, Alex Elder <elder@kernel.org>, "David S. Miller" <davem@davemloft.net>, Jakub Kicinski <kuba@kernel.org>, Andy Gross <agross@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>, Sudeep Holla <sudeep.holla@arm.com>, linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, iommu@lists.linux-foundation.org, linux-media@vger.kernel.org, linux-mmc@vger.kernel.org, netdev@vger.kernel.org, ath10k@lists.infradead.org, linux-wireless@vger.kernel.org, linux-gpio@vger.kernel.org

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(-)
> 

. . .