Re: [RFC PATCH 03/12] arm64: kvm: Cleanup VTCR_EL2/VTTBR computation

Marc Zyngier
2016-03-16T15:44:54Z

On Wed, 16 Mar 2016 15:37:18 +0000
"Suzuki K. Poulose" <Suzuki.Poulose@arm.com> wrote:

> On 16/03/16 15:01, Marc Zyngier wrote:
> > On 14/03/16 16:53, Suzuki K Poulose wrote:
> >> No functional changes. Group the common bits for VCTR_EL2
> >> initialisation for better readability. The granule size
> >> and the entry level are controlled by the page size.
>
> >>
> >> diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
> >> index b7d61e4..d49dd50 100644
> >> --- a/arch/arm64/include/asm/kvm_arm.h
> >> +++ b/arch/arm64/include/asm/kvm_arm.h
> >> @@ -139,32 +139,30 @@
> >> * The magic numbers used for VTTBR_X in this patch can be found in Tables
> >> * D4-23 and D4-25 in ARM DDI 0487A.b.
> >> */
>
> ...
>
> >>
> >> +#define VTCR_EL2_FLAGS (VTCR_EL2_TGRAN_FLAGS | VTCR_EL2_COMMON_BITS)
> >> +#define VTTBR_X ((VTTBR_X_TGRAN_MAGIC) - VTCR_EL2_T0SZ_40B)
> >
> > Nit: spurious brackets.
>
> Will remove them.
>
> > It would be nice to add an ARMv8 ARM reference to where the "magic"
> > value is coming from.
>
> That reference already exists in the code, see above.

Ah, good point!

Thanks,

M.
--
Jazz is not dead. It just smells funny.