Re: [PATCH 1/2] arm64: Add Cortex-X2 CPU part definition

[Anshuman Khandual]

On 1/12/22 4:20 PM, Arnd Bergmann wrote:
> On Wed, Jan 12, 2022 at 10:34 AM Anshuman Khandual
> <anshuman.khandual@xxxxxxx> wrote:
>>
>> Add the CPU Partnumbers for the new Arm designs.
>>
>> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
>> Cc: Will Deacon <will@xxxxxxxxxx>
>> Cc: Suzuki Poulose <suzuki.poulose@xxxxxxx>
>> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
>> Cc: linux-kernel@xxxxxxxxxxxxxxx
>> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
>> ---
>>  arch/arm64/include/asm/cputype.h | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
>> index 19b8441aa8f2..657eeb06c784 100644
>> --- a/arch/arm64/include/asm/cputype.h
>> +++ b/arch/arm64/include/asm/cputype.h
>> @@ -74,6 +74,7 @@
>>  #define ARM_CPU_PART_NEOVERSE_N1       0xD0C
>>  #define ARM_CPU_PART_CORTEX_A77                0xD0D
>>  #define ARM_CPU_PART_CORTEX_A710       0xD47
>> +#define ARM_CPU_PART_CORTEX_X2         0xD48
>>  #define ARM_CPU_PART_NEOVERSE_N2       0xD49
> 
> No objections to the patch, but would it be possible to just add all the missing
> ones here to the degree that they are known already? I don't see any entries for
> Cortex-A34, Cortex-A65AE, Cortex-A78, Cortex-A78C, Cortex-A78AE,
> Neoverse-E1, Neoverse-V1, Cortex-X1, Cortex-X2, Cortex-A510, Cortex-A710
> and Cortex-R82 among the Arm-designed cores that can run Linux, and there
> are probably others that I missed going through the list.

Hi Arnd,

IIUC the part numbers are enumerated here only if there is an errata
applicable for them which needs to be detected at boot. I am not sure
whether all cpu versions that can run Linux, needs to be defined here.
But then I might be missing something.

- Anshuman

> 
>         Arnd
>