powerpc: Fix /proc/cpuinfo revision for POWER9 DD2

[Michael Ellerman]

On Thu, 2017-06-15 at 01:53:16 UTC, Michael Neuling wrote:
> The P9 PVR bits 12-15 don't indicate a revision but instead different
> chip configurations.  From BookIV we have:
>    Bits      Configuration
>     0 :    Scale out 12 cores
>     1 :    Scale out 24 cores
>     2 :    Scale up  12 cores
>     3 :    Scale up  24 cores
> 
> DD1 doesn't use this but DD2 does. Linux will mostly use the "Scale
> out 24 core" configuration (ie. SMT4 not SMT8) which results in a PVR
> of 0x004e1200. The reported revision in /proc/cpuinfo is hence
> reported incorrectly as "18.0".
> 
> This patch fixes this to mask off only the relevant bits for the major
> revision (ie. bits 8-11) for POWER9.
> 
> Signed-off-by: Michael Neuling <mikey at neuling.org>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/64ebb9a208c6e66316329a6d910181

cheers