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From: Marc Zyngier <maz@kernel.org>
To: kvmarm@lists.linux.dev, kvm@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Cc: James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Oliver Upton <oliver.upton@linux.dev>,
	Zenghui Yu <yuzenghui@huawei.com>,
	Ricardo Koller <ricarkol@google.com>,
	Simon Veith <sveith@amazon.de>,
	Reiji Watanabe <reijiw@google.com>,
	Colton Lewis <coltonlewis@google.com>,
	Joey Gouly <joey.gouly@arm.com>,
	dwmw2@infradead.org
Subject: [PATCH v2 04/19] arm64: Add HAS_ECV_CNTPOFF capability
Date: Mon, 13 Mar 2023 12:48:22 +0000	[thread overview]
Message-ID: <20230313124837.2264882-5-maz@kernel.org> (raw)
In-Reply-To: <20230313124837.2264882-1-maz@kernel.org>

Add the probing code for the FEAT_ECV variant that implements CNTPOFF_EL2.
Why it is optional is a mystery, but let's try and detect it.

Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/kernel/cpufeature.c | 11 +++++++++++
 arch/arm64/tools/cpucaps       |  1 +
 2 files changed, 12 insertions(+)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 2e3e55139777..c331c49a7d19 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2223,6 +2223,17 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
 		.sign = FTR_UNSIGNED,
 		.min_field_value = 1,
 	},
+	{
+		.desc = "Enhanced Counter Virtualization (CNTPOFF)",
+		.capability = ARM64_HAS_ECV_CNTPOFF,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
+		.matches = has_cpuid_feature,
+		.sys_reg = SYS_ID_AA64MMFR0_EL1,
+		.field_pos = ID_AA64MMFR0_EL1_ECV_SHIFT,
+		.field_width = 4,
+		.sign = FTR_UNSIGNED,
+		.min_field_value = ID_AA64MMFR0_EL1_ECV_CNTPOFF,
+	},
 #ifdef CONFIG_ARM64_PAN
 	{
 		.desc = "Privileged Access Never",
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index 37b1340e9646..40ba95472594 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -23,6 +23,7 @@ HAS_DCPOP
 HAS_DIT
 HAS_E0PD
 HAS_ECV
+HAS_ECV_CNTPOFF
 HAS_EPAN
 HAS_GENERIC_AUTH
 HAS_GENERIC_AUTH_ARCH_QARMA3
-- 
2.34.1


  parent reply	other threads:[~2023-03-13 12:48 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-13 12:48 [PATCH v2 00/19] KVM: arm64: Rework timer offsetting for fun and profit Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 01/19] KVM: arm64: timers: Convert per-vcpu virtual offset to a global value Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 02/19] KVM: arm64: timers: Use a per-vcpu, per-timer accumulator for fractional ns Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 03/19] arm64: Add CNTPOFF_EL2 register definition Marc Zyngier
2023-03-13 12:48 ` Marc Zyngier [this message]
2023-03-13 12:48 ` [PATCH v2 05/19] KVM: arm64: timers: Use CNTPOFF_EL2 to offset the physical timer Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 06/19] KVM: arm64: timers: Allow physical offset without CNTPOFF_EL2 Marc Zyngier
2023-03-13 16:43   ` Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 07/19] KVM: arm64: Expose {un,}lock_all_vcpus() to the reset of KVM Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 08/19] KVM: arm64: timers: Allow userspace to set the global counter offset Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 09/19] KVM: arm64: timers: Allow save/restoring of the physical timer Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 10/19] KVM: arm64: timers: Rationalise per-vcpu timer init Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 11/19] KVM: arm64: timers: Abstract per-timer IRQ access Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 12/19] KVM: arm64: timers: Move the timer IRQs into arch_timer_vm_data Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 13/19] KVM: arm64: Abstract the number of valid timers per vcpu Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 14/19] KVM: arm64: Document KVM_ARM_SET_CNT_OFFSETS and co Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 15/19] KVM: arm64: nv: timers: Add a per-timer, per-vcpu offset Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 16/19] KVM: arm64: nv: timers: Support hyp timer emulation Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 17/19] KVM: arm64: selftests: Add physical timer registers to the sysreg list Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 18/19] KVM: arm64: selftests: Augment existing timer test to handle variable offset Marc Zyngier
2023-03-13 12:48 ` [PATCH v2 19/19] KVM: arm64: selftests: Deal with spurious timer interrupts Marc Zyngier
2023-03-23 22:19 ` [PATCH v2 00/19] KVM: arm64: Rework timer offsetting for fun and profit Colton Lewis
2023-03-23 22:54   ` Marc Zyngier

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