Re: [PATCH 18/21] arm64: dts: google: Add initial Google gs101 SoC support

[Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>]

On 05/10/2023 19:59, William McVicker wrote:
> On 10/05/2023, Peter Griffin wrote:
>> Google gs101 SoC is ARMv8 mobile SoC found in the Pixel 6,
>> (oriole) Pixel 6a (bluejay) and Pixel 6 pro (raven) mobile
>> phones. It features:
>> * 4xA55 little cluster
>> * 2xA76 Mid cluster
>> * 2xX1 Big cluster
>>
>> This commit adds the basic device tree for gs101 (SoC) and oriole
>> (pixel 6). Further platform support will be added over time.
>>
>> It has been tested with a minimal busybox initramfs and boots to
>> a shell.
>>
>> Signed-off-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
>> ---
>>  arch/arm64/Kconfig.platforms                  |    6 +
>>  arch/arm64/boot/dts/Makefile                  |    1 +
>>  arch/arm64/boot/dts/google/Makefile           |    6 +
>>  arch/arm64/boot/dts/google/gs101-oriole.dts   |   68 +
>>  arch/arm64/boot/dts/google/gs101-pinctrl.dtsi | 1134 +++++++++++++++++
>>  arch/arm64/boot/dts/google/gs101-pinctrl.h    |   17 +
>>  arch/arm64/boot/dts/google/gs101.dtsi         |  501 ++++++++
>>  7 files changed, 1733 insertions(+)
>>  create mode 100644 arch/arm64/boot/dts/google/Makefile
>>  create mode 100644 arch/arm64/boot/dts/google/gs101-oriole.dts
>>  create mode 100644 arch/arm64/boot/dts/google/gs101-pinctrl.dtsi
>>  create mode 100644 arch/arm64/boot/dts/google/gs101-pinctrl.h
>>  create mode 100644 arch/arm64/boot/dts/google/gs101.dtsi
>>
>> diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
>> index 6069120199bb..a5ed1b719488 100644
>> --- a/arch/arm64/Kconfig.platforms
>> +++ b/arch/arm64/Kconfig.platforms
>> @@ -107,6 +107,12 @@ config ARCH_EXYNOS
>>  	help
>>  	  This enables support for ARMv8 based Samsung Exynos SoC family.
>>  
>> +config ARCH_GOOGLE_TENSOR
>> +	bool "Google Tensor SoC fmaily"
>> +	depends on ARCH_EXYNOS
>> +	help
>> +	  Support for ARMv8 based Google Tensor platforms.
> 
> I'd like to bring up this thread and discuss the option of not introducing
> another ARCH_* config:
> 
>   https://lore.kernel.org/all/20200306103652.GA3634389@xxxxxxxxx/
> 
> I especially don't like the "depends on ARCH_EXYNOS" because that forces one to
> include all the other Exynos drivers that ARCH_EXYNOS selects that Google

Since we are creating unified kernel images, having other drivers is not
a problem.

> Tensor SoCs don't need. Can we consider using SOC_GOOGLE instead and for all

SOC_GOOGLE will work exactly the same and depend on ARCH_EXYNOS or
appear everywhere as ARCH_EXYNOS. We already had this talk with Tesla.


> drivers that actually depend on the SoC hardware, we can just add "depends on
> SOC_GOOGLE"?
> 
> The idea is that drivers should be tied to hardware -- not a specific vendor.

And hardware is Exynos. Tesla FSD and Google Tensor is Exynos, even if
you do no like calling it.

> By making drivers depend on ARCH_*, you are introducing an arbitrary vendor
> dependency and not a hardware dependency.

There is no arbitrary dependency. We call it all Exynos hardware,
because this is Exynos.

I remember what you were pushing for removal of ARCH_EXYNOS and there
waas clear feedback, not only from me: this is against communities goals.

> 
> Thanks,
> Will

Please trim the replies from unrelated context.


Best regards,
Krzysztof