From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C16951CF8C for ; Mon, 13 Nov 2023 12:16:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ua/F/3rg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 21713C433C7; Mon, 13 Nov 2023 12:16:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699877764; bh=ECkffLkgXxykU08JwLrAkP2+a1KDHfkL6mRTpz7fhHo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Ua/F/3rggkyDm8yGAR8HbQ3M6mazPJeWYWsdR4YQ5o3ss/FTa2atvLo0wZHc9XfbT JsAeZwQ78CRijUk1gIgsC1rsdj0RCXvZvexYCanLGa4LpnEAfOiLNoKtUCEXNEFwJ/ zfvQf0JhKzvKbxNy7+Ui9IiThl84EAL4p/cz+TMUVoqSla4GyywdXBtM3w2k5yUdNG ef/EI6TQ5lMRjQJE1yaRgrJSlCSCCeWqY87C6EERnFBp+Iphs5Nm4VQXTT1h9hfR8+ l6SyZTqQcUfeIaTqibMX2UDIZV+VDIJBPZlww/3v1jtw6cab/ay+6V6ToJVTSy8M9K uOMHVTb2xqXPA== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1r2VrF-00CfnB-K8; Mon, 13 Nov 2023 12:16:01 +0000 Date: Mon, 13 Nov 2023 12:16:01 +0000 Message-ID: <86a5rh26im.wl-maz@kernel.org> From: Marc Zyngier To: Ryan Roberts Cc: Catalin Marinas , Will Deacon , Oliver Upton , Suzuki K Poulose , James Morse , Zenghui Yu , Ard Biesheuvel , Anshuman Khandual , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Subject: Re: [PATCH v4 04/12] KVM: arm64: Add ARM64_HAS_LPA2 CPU capability In-Reply-To: <1d742c1f-2f2d-4d73-8530-b7e2b688287f@arm.com> References: <20231009185008.3803879-1-ryan.roberts@arm.com> <20231009185008.3803879-5-ryan.roberts@arm.com> <86cyx9n1yp.wl-maz@kernel.org> <1d742c1f-2f2d-4d73-8530-b7e2b688287f@arm.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/29.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: ryan.roberts@arm.com, catalin.marinas@arm.com, will@kernel.org, oliver.upton@linux.dev, suzuki.poulose@arm.com, james.morse@arm.com, yuzenghui@huawei.com, ardb@kernel.org, anshuman.khandual@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Mon, 13 Nov 2023 11:57:45 +0000, Ryan Roberts wrote: > > >> +{ > >> +#if defined(CONFIG_ARM64_4K_PAGES) || defined(CONFIG_ARM64_16K_PAGES) > >> + unsigned int tgran; > >> + > >> + tgran = cpuid_feature_extract_unsigned_field(mmfr0, > >> + ID_AA64MMFR0_EL1_TGRAN_SHIFT); > >> + return tgran == ID_AA64MMFR0_EL1_TGRAN_LPA2; > >> +#else > >> + return false; > >> +#endif > > > > Writing this using IS_ENABLED() would be slightly more pleasing to my > > tired eyes... ;-) > > Unfortunately this doesn't work because ID_AA64MMFR0_EL1_TGRAN_LPA2 is only > defined for 4K and 16K configs (there is no field ofr 64K). So proposing to do > it this way instead. Please shout if you have a better idea: > > #if defined(CONFIG_ARM64_4K_PAGES) || defined(CONFIG_ARM64_16K_PAGES) > static bool has_lpa2_at_stage1(u64 mmfr0) > { > unsigned int tgran; > > tgran = cpuid_feature_extract_unsigned_field(mmfr0, > ID_AA64MMFR0_EL1_TGRAN_SHIFT); > return tgran == ID_AA64MMFR0_EL1_TGRAN_LPA2; > } > > static bool has_lpa2_at_stage2(u64 mmfr0) > { > unsigned int tgran; > > tgran = cpuid_feature_extract_unsigned_field(mmfr0, > ID_AA64MMFR0_EL1_TGRAN_2_SHIFT); > return tgran == ID_AA64MMFR0_EL1_TGRAN_2_SUPPORTED_LPA2; > } > > static bool has_lpa2(const struct arm64_cpu_capabilities *entry, int scope) > { > u64 mmfr0; > > mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); > return has_lpa2_at_stage1(mmfr0) && has_lpa2_at_stage2(mmfr0); > } > #else > static bool has_lpa2(const struct arm64_cpu_capabilities *entry, int scope) > { > return false; > } > #endif Ah, fair enough. This looks marginally better anyway. Thanks, M. -- Without deviation from the norm, progress is not possible. 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Mon, 13 Nov 2023 12:16:01 +0000 Date: Mon, 13 Nov 2023 12:16:01 +0000 Message-ID: <86a5rh26im.wl-maz@kernel.org> From: Marc Zyngier To: Ryan Roberts Cc: Catalin Marinas , Will Deacon , Oliver Upton , Suzuki K Poulose , James Morse , Zenghui Yu , Ard Biesheuvel , Anshuman Khandual , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Subject: Re: [PATCH v4 04/12] KVM: arm64: Add ARM64_HAS_LPA2 CPU capability In-Reply-To: <1d742c1f-2f2d-4d73-8530-b7e2b688287f@arm.com> References: <20231009185008.3803879-1-ryan.roberts@arm.com> <20231009185008.3803879-5-ryan.roberts@arm.com> <86cyx9n1yp.wl-maz@kernel.org> <1d742c1f-2f2d-4d73-8530-b7e2b688287f@arm.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/29.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: ryan.roberts@arm.com, catalin.marinas@arm.com, will@kernel.org, oliver.upton@linux.dev, suzuki.poulose@arm.com, james.morse@arm.com, yuzenghui@huawei.com, ardb@kernel.org, anshuman.khandual@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231113_041612_012249_BD15184E X-CRM114-Status: GOOD ( 14.93 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, 13 Nov 2023 11:57:45 +0000, Ryan Roberts wrote: > > >> +{ > >> +#if defined(CONFIG_ARM64_4K_PAGES) || defined(CONFIG_ARM64_16K_PAGES) > >> + unsigned int tgran; > >> + > >> + tgran = cpuid_feature_extract_unsigned_field(mmfr0, > >> + ID_AA64MMFR0_EL1_TGRAN_SHIFT); > >> + return tgran == ID_AA64MMFR0_EL1_TGRAN_LPA2; > >> +#else > >> + return false; > >> +#endif > > > > Writing this using IS_ENABLED() would be slightly more pleasing to my > > tired eyes... ;-) > > Unfortunately this doesn't work because ID_AA64MMFR0_EL1_TGRAN_LPA2 is only > defined for 4K and 16K configs (there is no field ofr 64K). So proposing to do > it this way instead. Please shout if you have a better idea: > > #if defined(CONFIG_ARM64_4K_PAGES) || defined(CONFIG_ARM64_16K_PAGES) > static bool has_lpa2_at_stage1(u64 mmfr0) > { > unsigned int tgran; > > tgran = cpuid_feature_extract_unsigned_field(mmfr0, > ID_AA64MMFR0_EL1_TGRAN_SHIFT); > return tgran == ID_AA64MMFR0_EL1_TGRAN_LPA2; > } > > static bool has_lpa2_at_stage2(u64 mmfr0) > { > unsigned int tgran; > > tgran = cpuid_feature_extract_unsigned_field(mmfr0, > ID_AA64MMFR0_EL1_TGRAN_2_SHIFT); > return tgran == ID_AA64MMFR0_EL1_TGRAN_2_SUPPORTED_LPA2; > } > > static bool has_lpa2(const struct arm64_cpu_capabilities *entry, int scope) > { > u64 mmfr0; > > mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); > return has_lpa2_at_stage1(mmfr0) && has_lpa2_at_stage2(mmfr0); > } > #else > static bool has_lpa2(const struct arm64_cpu_capabilities *entry, int scope) > { > return false; > } > #endif Ah, fair enough. This looks marginally better anyway. Thanks, M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel