From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Martin <Dave.Martin@arm.com>
Subject: Re: [PATCH v4 6/6] arm64: Advertise ARM64_HAS_DCPODP cpu feature
Date: Wed, 3 Apr 2019 14:21:54 +0100
Message-ID: <20190403132154.GU3567@e103592.cambridge.arm.com>
References: <20190403105628.39798-1-andrew.murray@arm.com>
 <20190403105628.39798-7-andrew.murray@arm.com>
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In-Reply-To: <20190403105628.39798-7-andrew.murray@arm.com>
To: Andrew Murray <andrew.murray@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will.deacon@arm.com>, Szabolcs Nagy <Szabolcs.Nagy@arm.com>, linux-arm-kernel@lists.infradead.org, Mark Rutland <mark.rutland@arm.com>, Phil Blundell <pb@pbcl.net>, libc-alpha@sourceware.org, linux-api@vger.kernel.org, Suzuki K Poulose <suzuki.poulose@arm.com>
List-Id: linux-api@vger.kernel.org

On Wed, Apr 03, 2019 at 11:56:28AM +0100, Andrew Murray wrote:
> Advertise ARM64_HAS_DCPODP when both DC CVAP and DC CVADP are supported.
> 
> Even though we don't use this feature now, we provide it for consistency
> with DCPOP and anticipate it being used in the future.
> 
> Signed-off-by: Andrew Murray <andrew.murray@arm.com>

Reviewed-by: Dave Martin <Dave.Martin@arm.com>

> ---
>  arch/arm64/include/asm/cpucaps.h | 3 ++-
>  arch/arm64/kernel/cpufeature.c   | 9 +++++++++
>  2 files changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
> index f6a76e43f39e..defdc67d9ab4 100644
> --- a/arch/arm64/include/asm/cpucaps.h
> +++ b/arch/arm64/include/asm/cpucaps.h
> @@ -61,7 +61,8 @@
>  #define ARM64_HAS_GENERIC_AUTH_ARCH		40
>  #define ARM64_HAS_GENERIC_AUTH_IMP_DEF		41
>  #define ARM64_HAS_IRQ_PRIO_MASKING		42
> +#define ARM64_HAS_DCPODP			43
>  
> -#define ARM64_NCAPS				43
> +#define ARM64_NCAPS				44
>  
>  #endif /* __ASM_CPUCAPS_H */
> diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
> index f8b682a3a9f4..4ee5d63281ae 100644
> --- a/arch/arm64/kernel/cpufeature.c
> +++ b/arch/arm64/kernel/cpufeature.c
> @@ -1340,6 +1340,15 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
>  		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
>  		.min_field_value = 1,
>  	},
> +	{
> +		.desc = "Data cache clean to Point of Deep Persistence",
> +		.capability = ARM64_HAS_DCPODP,
> +		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
> +		.matches = has_cpuid_feature,
> +		.sys_reg = SYS_ID_AA64ISAR1_EL1,
> +		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
> +		.min_field_value = 2,
> +	},
>  #endif
>  #ifdef CONFIG_ARM64_SVE
>  	{
> -- 
> 2.21.0
>