Re: ARM errata 430973 on multi platform kernels

[Sebastian Reichel <sre@kernel.org>]

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Hi,

On Mon, Apr 06, 2015 at 07:23:13PM -0700, Tony Lindgren wrote:
> I'm now thinking the kernel should just always set the 430973 specific
> cpu_v7_switch_mm for all cortex-a8 if IBE bit is set. That avoids
> the whole mess of early SoC detection and smc calls. And if IBE bit
> is not set, then we just use the regular cpu_v7_switch_mm.
>
> This will work as long as we can read the aux ctrl register IBE
> bit using mrc, which I believe is the case for all cortex-a8 based
> omap variants.

If I understood it correctly we can simply call the BTB flush on
cortex-a8 if IBE bit is not set, since it would be translated as
nop.

So it should be safe to include the call on all cortex-a8 based
cpus. We may need a non-BTB-flushing function for non-cortex-a8
based cpus, though.

-- Sebastian

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