From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Zyngier <marc.zyngier@arm.com>
Subject: Re: [RFC PATCH 02/12] arm64: kvm: Fix {V}TCR_EL2_TG0 mask
Date: Wed, 16 Mar 2016 14:54:30 +0000
Message-ID: <56E973A6.7020004@arm.com>
References: <1457974391-28456-1-git-send-email-suzuki.poulose@arm.com>
 <1457974391-28456-3-git-send-email-suzuki.poulose@arm.com>
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Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org,
	mark.rutland@arm.com, kvm@vger.kernel.org, will.deacon@arm.com,
	catalin.marinas@arm.com
To: Suzuki K Poulose <suzuki.poulose@arm.com>,
	christoffer.dall@linaro.org
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On 14/03/16 16:53, Suzuki K Poulose wrote:
> {V}TCR_EL2_TG0 is a 2bit wide field, where:
> 
>  00 - 4K
>  01 - 64K
>  10 - 16K
> 
> But we use only 1 bit, which has worked well so far since
> we never cared about 16K. Fix it for 16K support.
> 
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Marc Zyngier <marc.zyngier@arm.com>
> Cc: Christoffer Dall <christoffer.dall@linaro.org>
> Cc: kvmarm@lists.cs.columbia.edu
> Acked-by: Mark Rutland <mark.rutland@arm.com>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> ---
>  arch/arm64/include/asm/kvm_arm.h |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
> index d201d4b..b7d61e4 100644
> --- a/arch/arm64/include/asm/kvm_arm.h
> +++ b/arch/arm64/include/asm/kvm_arm.h
> @@ -99,7 +99,7 @@
>  #define TCR_EL2_TBI	(1 << 20)
>  #define TCR_EL2_PS	(7 << 16)
>  #define TCR_EL2_PS_40B	(2 << 16)
> -#define TCR_EL2_TG0	(1 << 14)
> +#define TCR_EL2_TG0	(3 << 14)
>  #define TCR_EL2_SH0	(3 << 12)
>  #define TCR_EL2_ORGN0	(3 << 10)
>  #define TCR_EL2_IRGN0	(3 << 8)
> @@ -110,7 +110,7 @@
>  /* VTCR_EL2 Registers bits */
>  #define VTCR_EL2_RES1		(1 << 31)
>  #define VTCR_EL2_PS_MASK	(7 << 16)
> -#define VTCR_EL2_TG0_MASK	(1 << 14)
> +#define VTCR_EL2_TG0_MASK	(3 << 14)
>  #define VTCR_EL2_TG0_4K		(0 << 14)
>  #define VTCR_EL2_TG0_64K	(1 << 14)
>  #define VTCR_EL2_SH0_MASK	(3 << 12)
> 

As we already have arch/arm64/include/asm/pgtable-hwdef.h defining
TCR_TG0_{4,16,64}K, would it make sense to reuse those and drop the
locally defined values? Something like:

#define TCR_EL2_TG0_4K	TCR_TG0_4K

?

Thanks,

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