Messages in this thread | | | Date | Wed, 27 Sep 2017 14:39:32 +0100 | From | Mark Rutland <> | Subject | Re: [PATCH 3/3] arm64: cpuinfo: display product info in /proc/cpuinfo |
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Hi,
On Wed, Sep 27, 2017 at 11:42:07AM +0100, Robin Murphy wrote: > On 26/09/17 23:23, Al Stone wrote: > > + seq_printf(m, ", ARM 8.%d (r%dp%d) CPU", > > + MIDR_VARIANT(midr), > > + MIDR_VARIANT(midr), > > + MIDR_REVISION(midr)); > > What is "ARM 8.1" meant to infer for, say, a typical Cortex-A57?
Just to make Robin's point a little clearer, MIDR_EL1.Variant is IMPLEMENTATION DEFINED, and doesn't describe the ARMv8.x architecture revision.
For example, on Cortex A57 is contains the major revision number of the CPU, and is 1 for any r1pY Cortex-A57 (e.g. those on Juno R1).
For better or worse, the architecture provides us no mechanism to determine the architecture revision.
Thanks, Mark.
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