Re: [PATCH v2 20/21] MIPS: generic: Add support for Mobileye EyeQ5

Jiaxun Yang
2023-12-01T10:50:00Z

在2023年12月1日十二月 上午10:34，Gregory CLEMENT写道：
> "Jiaxun Yang" <jiaxun.yang@flygoat.com> writes:
>
>> 在2023年11月23日十一月 下午3:26，Gregory CLEMENT写道：
>>> Introduce support for the MIPS based Mobileye EyeQ5 SoCs.
>>>
>>> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
>>> ---
>> [...]
>>> diff --git a/arch/mips/generic/Kconfig b/arch/mips/generic/Kconfig
>>> index 7dc5b3821cc6e..04e1fc6f789b5 100644
>>> --- a/arch/mips/generic/Kconfig
>>> +++ b/arch/mips/generic/Kconfig
>>> @@ -48,6 +48,13 @@ config SOC_VCOREIII
>>> config MSCC_OCELOT
>>> bool
>>>
>>> +config SOC_EYEQ5
>>> + select ARM_AMBA
>>> + select WEAK_ORDERING
>>> + select WEAK_REORDERING_BEYOND_LLSC
>>> + select PHYSICAL_START_BOOL
>>> + bool
>>
>> ^ I believe WEAK_ORDERING is already selected by MIPS_CPS,
>
> But MIPS_CPS can be disabled: it is not selected by
> MIPS_GENERIC_KERNEL.

IMO if MIPS_CPS is not select then there is no SMP support on this platform.
WEAK_ORDERING only make sense for SMP system.

>
>> and WEAK_REORDERING_BEYOND_LLSC should be selected by MIPS_CPS as well.
>
> WEAK_REORDERING_BEYOND_LLSC is only selected by CPU_LOONGSON64 for
> now not by MIPS_CPS

I believe this applies to all SMP cores from MTI, I'll check with hardware
folks.

Thanks
- Jiaxun

>
> Thanks,
>
> Gregory
>>
>> Thanks
>> --
>> - Jiaxun
>
> --
> Gregory Clement, Bootlin
> Embedded Linux and Kernel engineering
> http://bootlin.com

--
- Jiaxun