[PATCHv3 08/11] arm64: Check for selected granule support
Suzuki K. Poulose
Suzuki.Poulose at arm.com
Thu Oct 15 02:45:54 PDT 2015
On 14/10/15 18:24, Mark Rutland wrote:
>> - * other registers depend on the function called upon completion
>> + * Other registers depend on the function called upon completion.
>> + *
>> + * Checks if the selected granule size is supported by the CPU.
>> + * If it doesn't park the CPU
> Nit: "If it isn't, park the CPU."
>> +#if defined(CONFIG_ARM64_64K_PAGES)
>> +#define id_aa64mmfr0_tgran_shift ID_AA64MMFR0_TGRAN64_SHIFT
>> +#define id_aa64mmfr0_tgran_on ID_AA64MMFR0_TGRAN64_ON
>> +#define id_aa64mmfr0_tgran_shift ID_AA64MMFR0_TGRAN4_SHIFT
>> +#define id_aa64mmfr0_tgran_on ID_AA64MMFR0_TGRAN4_ON
> Any reason for not using upper-case names for the macros?
Nothing in particular. I had them in upper-case in the previous version,
changed it here ;) for absolutely no reason. I could switch it back.
> Given they're local you could just call them TGRAN_SHIFT and TRGRAN_ON
> to make the asm slightly nicer.
Given Jeremy's suggestion to add something to the EFI stub, I will retain
the original definition with all upper-case and define it somewhere in
a header so that we can reuse it.
>> + wfe
>> + b __no_granule_support
> Other than the above, this loogs fine to me.
> In future it would be nice if we could somehow signal that these dead
> CPUs are trapped in the kernel -- we should have some kind of canary
> mechanism for that. That needn't block this patch, though.
Yes, we should.
Thanks for the review
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