linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Marc Zyngier <maz@kernel.org>
To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev
Cc: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Ard Biesheuvel <ardb@kernel.org>,
	James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Oliver Upton <oliver.upton@linux.dev>,
	Zenghui Yu <yuzenghui@huawei.com>
Subject: [PATCH v3 06/13] arm64: cpufeature: Detect E2H0 not being implemented
Date: Mon, 27 Nov 2023 11:45:52 +0000	[thread overview]
Message-ID: <20231127114559.990314-7-maz@kernel.org> (raw)
In-Reply-To: <20231127114559.990314-1-maz@kernel.org>

FEAT_E2H0 is a new feature that indicates whether or not HCR_EL2.E2H
can be set to 0. Amusingly, this feature is set to 0 when implemented,
and otherwise negative.

Add a new capability and detection infrastructure to detect the
absence of FEAT_E2H0.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/kernel/cpufeature.c | 7 +++++++
 arch/arm64/tools/cpucaps       | 1 +
 2 files changed, 8 insertions(+)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 4a72fb26daec..6ef9811f7bb7 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2786,6 +2786,13 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
 		.matches = has_cpuid_feature,
 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, EVT, IMP)
 	},
+	{
+		.desc = "FEAT_E2H0 not implemented",
+		.capability = ARM64_HCR_E2H_RES1,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
+		.matches = has_cpuid_feature,
+		ARM64_CPUID_FIELDS_NEG(ID_AA64MMFR4_EL1, E2H0, NI)
+	},
 	{},
 };
 
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index b98c38288a9d..8866ea9bf995 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -52,6 +52,7 @@ HAS_TIDCP1
 HAS_TLB_RANGE
 HAS_VIRT_HOST_EXTN
 HAS_WFXT
+HCR_E2H_RES1
 HW_DBM
 KVM_HVHE
 KVM_PROTECTED_MODE
-- 
2.39.2


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply	other threads:[~2023-11-27 11:46 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-27 11:45 [PATCH v3 00/13] arm64: Add support for FEAT_E2H0, or lack thereof Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 01/13] arm64: Add macro to compose a sysreg field value Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 02/13] arm64: cpufeatures: Correctly handle signed values Marc Zyngier
2023-12-11 12:24   ` Will Deacon
2024-01-08 17:46     ` Marc Zyngier
2024-01-09 11:40       ` Marc Zyngier
2024-01-30 11:34         ` Will Deacon
2023-11-27 11:45 ` [PATCH v3 03/13] arm64: cpufeature: Correctly display signed override values Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 04/13] arm64: sysreg: Add layout for ID_AA64MMFR4_EL1 Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 05/13] arm64: cpufeature: Add ID_AA64MMFR4_EL1 handling Marc Zyngier
2023-11-27 11:45 ` Marc Zyngier [this message]
2023-12-11 12:42   ` [PATCH v3 06/13] arm64: cpufeature: Detect E2H0 not being implemented Will Deacon
2024-01-09 15:16     ` Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 07/13] arm64: cpufeature: Detect HCR_EL2.NV1 being RES0 Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 08/13] arm64: Treat HCR_EL2.E2H as RES1 when ID_AA64MMFR4_EL1.E2H0 is negative Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 09/13] arm64: Add override for ID_AA64MMFR4_EL1.E2H0 Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 10/13] arm64: Add MIDR-based override infrastructure Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 11/13] arm64: Add MIDR-based overrides for ID_AA64MMFR4_EL1.E2H0 Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 12/13] KVM: arm64: Expose ID_AA64MMFR4_EL1 to guests Marc Zyngier
2023-11-27 11:45 ` [PATCH v3 13/13] KVM: arm64: Force guest's HCR_EL2.E2H RES1 when NV1 is not implemented Marc Zyngier

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20231127114559.990314-7-maz@kernel.org \
    --to=maz@kernel.org \
    --cc=ardb@kernel.org \
    --cc=catalin.marinas@arm.com \
    --cc=james.morse@arm.com \
    --cc=kvmarm@lists.linux.dev \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=mark.rutland@arm.com \
    --cc=oliver.upton@linux.dev \
    --cc=suzuki.poulose@arm.com \
    --cc=will@kernel.org \
    --cc=yuzenghui@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).