From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E4289B673 for ; Thu, 21 Mar 2024 16:57:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711040266; cv=none; b=UISNkkbyY2O/SfNrMODWNZIquVLJiVWLjBHhlyjJkg4eQPEbodS7kLanUURF3ecTjAOLBTuKiSBrKs5uZdAuBbadgmy4bQCnj3Tu8hpM2PCDnqt5rYRuI3cci84UMM37V4tqlxdNARMQZxNZRX4sFy9PCksxHIKLL/AM9j8xLnw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711040266; c=relaxed/simple; bh=7/M1U7HIhSqSZiNSk95t3uWlAWU6EyJPYbvRFRZUS7c=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=rKg2PYiMP2Rfi9eudwLGounI/cD9K6pJXyf7CaOvpv4bJ3qWCFPI1r1x1zIb27g4j1JwGY3wujw1sTKQ8yQlEL4Z8rm/q2pmlBOfEeJg+c+TjFM6ZhTf5vr5j77WLKdkNqfV5EdjwNvjIYficB7pkDQi632O9qQop95MQ3fBM6Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id CD19D1063; Thu, 21 Mar 2024 09:58:18 -0700 (PDT) Received: from merodach.members.linode.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3BBF13F67D; Thu, 21 Mar 2024 09:57:43 -0700 (PDT) From: James Morse To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Cc: Marc Zyngier , Oliver Upton , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Jing Zhang , James Morse Subject: [PATCH v3 1/6] arm64: head.S: Initialise MPAM EL2 registers and disable traps Date: Thu, 21 Mar 2024 16:57:23 +0000 Message-Id: <20240321165728.31907-2-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20240321165728.31907-1-james.morse@arm.com> References: <20240321165728.31907-1-james.morse@arm.com> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add code to head.S's el2_setup to detect MPAM and disable any EL2 traps. This register resets to an unknown value, setting it to the default parititons/pmg before we enable the MMU is the best thing to do. Kexec/kdump will depend on this if the previous kernel left the CPU configured with a restrictive configuration. If linux is booted at the highest implemented exception level el2_setup will clear the enable bit, disabling MPAM. This code can't be enabled until a subsequent patch adds the Kconfig and cpufeature boiler plate. Signed-off-by: James Morse --- arch/arm64/include/asm/el2_setup.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h index b7afaa026842..1e2181820a0a 100644 --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -208,6 +208,21 @@ msr spsr_el2, x0 .endm +.macro __init_el2_mpam +#ifdef CONFIG_ARM64_MPAM + /* Memory Partioning And Monitoring: disable EL2 traps */ + mrs x1, id_aa64pfr0_el1 + ubfx x0, x1, #ID_AA64PFR0_EL1_MPAM_SHIFT, #4 + cbz x0, .Lskip_mpam_\@ // skip if no MPAM + msr_s SYS_MPAM2_EL2, xzr // use the default partition + // and disable lower traps + mrs_s x0, SYS_MPAMIDR_EL1 + tbz x0, #17, .Lskip_mpam_\@ // skip if no MPAMHCR reg + msr_s SYS_MPAMHCR_EL2, xzr // clear TRAP_MPAMIDR_EL1 -> EL2 +.Lskip_mpam_\@: +#endif /* CONFIG_ARM64_MPAM */ +.endm + /** * Initialize EL2 registers to sane values. This should be called early on all * cores that were booted in EL2. Note that everything gets initialised as @@ -225,6 +240,7 @@ __init_el2_stage2 __init_el2_gicv3 __init_el2_hstr + __init_el2_mpam __init_el2_nvhe_idregs __init_el2_cptr __init_el2_fgt -- 2.39.2