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SubjectRe: [PATCH 9/9] arm64: Documentation - Expose CPU feature registers
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On Thursday 24 November 2016 07:10 PM, Suzuki K Poulose wrote:
> + d) CPU Identification :
> + MIDR_EL1 is exposed to help identify the processor. On a
> + heterogeneous system, this could be racy (just like getcpu()). The
> + process could be migrated to another CPU by the time it uses the
> + register value, unless the CPU affinity is set. Hence, there is no
> + guarantee that the value reflects the processor that it is
> + currently executing on. The REVIDR is not exposed due to this
> + constraint, as REVIDR makes sense only in conjunction with the
> + MIDR. Alternately, MIDR_EL1 and REVIDR_EL1 are exposed via sysfs
> + at:
> +
> + /sys/devices/system/cpu/cpu$ID/regs/identification/
> + \- midr
> + \- revidr
> +

This doesn't seem to be implemented in this patchset.

Siddhesh

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