Re: [PATCH V3 04/16] arm64/cpufeature: Introduce ID_PFR2 CPU register

[Mark Rutland <mark.rutland@arm.com>]

On Tue, May 05, 2020 at 12:16:07PM +0100, Mark Rutland wrote:
> On Tue, May 05, 2020 at 12:12:41PM +0100, Will Deacon wrote:
> > On Sat, May 02, 2020 at 07:03:53PM +0530, Anshuman Khandual wrote:
> > > This adds basic building blocks required for ID_PFR2 CPU register which
> > > provides information about the AArch32 programmers model which must be
> > > interpreted along with ID_PFR0 and ID_PFR1 CPU registers. This is added
> > > per ARM DDI 0487F.a specification.
> > > 
> > > Cc: Catalin Marinas <catalin.marinas@arm.com>
> > > Cc: Will Deacon <will@kernel.org>
> > > Cc: Marc Zyngier <maz@kernel.org>
> > > Cc: Mark Rutland <mark.rutland@arm.com>
> > > Cc: James Morse <james.morse@arm.com>
> > > Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
> > > Cc: kvmarm@lists.cs.columbia.edu
> > > Cc: linux-arm-kernel@lists.infradead.org
> > > Cc: linux-kernel@vger.kernel.org
> > > 
> > > Suggested-by: Mark Rutland <mark.rutland@arm.com>
> > > Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> > > Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> > > ---
> > >  arch/arm64/include/asm/cpu.h    |  1 +
> > >  arch/arm64/include/asm/sysreg.h |  4 ++++
> > >  arch/arm64/kernel/cpufeature.c  | 11 +++++++++++
> > >  arch/arm64/kernel/cpuinfo.c     |  1 +
> > >  arch/arm64/kvm/sys_regs.c       |  2 +-
> > >  5 files changed, 18 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h
> > > index b4a40535a3d8..464e828a994d 100644
> > > --- a/arch/arm64/include/asm/cpu.h
> > > +++ b/arch/arm64/include/asm/cpu.h
> > > @@ -46,6 +46,7 @@ struct cpuinfo_arm64 {
> > >  	u32		reg_id_mmfr3;
> > >  	u32		reg_id_pfr0;
> > >  	u32		reg_id_pfr1;
> > > +	u32		reg_id_pfr2;
> > >  
> > >  	u32		reg_mvfr0;
> > >  	u32		reg_mvfr1;
> > > diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
> > > index e5317a6367b6..c977449e02db 100644
> > > --- a/arch/arm64/include/asm/sysreg.h
> > > +++ b/arch/arm64/include/asm/sysreg.h
> > > @@ -153,6 +153,7 @@
> > >  #define SYS_MVFR0_EL1			sys_reg(3, 0, 0, 3, 0)
> > >  #define SYS_MVFR1_EL1			sys_reg(3, 0, 0, 3, 1)
> > >  #define SYS_MVFR2_EL1			sys_reg(3, 0, 0, 3, 2)
> > > +#define SYS_ID_PFR2_EL1			sys_reg(3, 0, 0, 3, 4)
> > 
> > nit: but please group these defines by name rather than encoding.
> 
> So far we've *always* grouped these by encoding in this file, so can we
> keep things that way for now? Otherwise we're inconsistent with both
> schemes.

Unless you just meant "please put a newline before this" to avoid
grouping without affecting ordering, in which case agreed!

Mark.