Re: [PATCH] powerpc: Fix P10 PVR revision in /proc/cpuinfo for SMT4 cores

[Vaidyanathan Srinivasan <svaidy@linux.ibm.com>]

* Michael Neuling <mikey@neuling.org> [2020-08-03 13:56:00]:

> On POWER10 bit 12 in the PVR indicates if the core is SMT4 or
> SMT8. Bit 12 is set for SMT4.
> 
> Without this patch, /proc/cpuinfo on a SMT4 DD1 POWER10 looks like
> this:
>     cpu             : POWER10, altivec supported
>     revision        : 17.0 (pvr 0080 1100)
> 
> Signed-off-by: Michael Neuling <mikey@neuling.org>

Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>

> ---
>  arch/powerpc/kernel/setup-common.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
> index b198b0ff25..808ec9fab6 100644
> --- a/arch/powerpc/kernel/setup-common.c
> +++ b/arch/powerpc/kernel/setup-common.c
> @@ -311,6 +311,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
>  				min = pvr & 0xFF;
>  				break;
>  			case 0x004e: /* POWER9 bits 12-15 give chip type */
> +			case 0x0080: /* POWER10 bit 12 gives SMT8/4 */

Correct. P9 and P10 have chip type (smt4 vs smt8 core) encoded in bits
PVR chip type bits 12-15.

Thanks for the fix.

--Vaidy