[PATCH v7 37/45] arm64: RME: Initialize PMCR.N with number counter supported by RMM
From: Steven Price <steven.price@arm.com>
Date: 2025-02-13 16:17:33
Also in:
kvm, kvmarm, linux-coco, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
From: Jean-Philippe Brucker <redacted> Provide an accurate number of available PMU counters to userspace when setting up a Realm. Signed-off-by: Jean-Philippe Brucker <redacted> Signed-off-by: Steven Price <steven.price@arm.com> --- arch/arm64/include/asm/kvm_rme.h | 1 + arch/arm64/kvm/pmu-emul.c | 3 +++ arch/arm64/kvm/rme.c | 5 +++++ 3 files changed, 9 insertions(+)
diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/asm/kvm_rme.h
index 67ee38541a82..8a8ec70f3626 100644
--- a/arch/arm64/include/asm/kvm_rme.h
+++ b/arch/arm64/include/asm/kvm_rme.h@@ -84,6 +84,7 @@ struct realm_rec { void kvm_init_rme(void); u32 kvm_realm_ipa_limit(void); u32 kvm_realm_vgic_nr_lr(void); +u8 kvm_realm_max_pmu_counters(void); u64 kvm_realm_reset_id_aa64dfr0_el1(const struct kvm_vcpu *vcpu, u64 val);
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index 670e5d15ad92..76ce59541e0f 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c@@ -997,6 +997,9 @@ u8 kvm_arm_pmu_get_max_counters(struct kvm *kvm) { struct arm_pmu *arm_pmu = kvm->arch.arm_pmu; + if (kvm_is_realm(kvm)) + return kvm_realm_max_pmu_counters(); + /* * The arm_pmu->cntr_mask considers the fixed counter(s) as well. * Ignore those and return only the general-purpose counters.
diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c
index f236e1776d8c..f620a64551d9 100644
--- a/arch/arm64/kvm/rme.c
+++ b/arch/arm64/kvm/rme.c@@ -87,6 +87,11 @@ u32 kvm_realm_vgic_nr_lr(void) return u64_get_bits(rmm_feat_reg0, RMI_FEATURE_REGISTER_0_GICV3_NUM_LRS); } +u8 kvm_realm_max_pmu_counters(void) +{ + return u64_get_bits(rmm_feat_reg0, RMI_FEATURE_REGISTER_0_PMU_NUM_CTRS); +} + u64 kvm_realm_reset_id_aa64dfr0_el1(const struct kvm_vcpu *vcpu, u64 val) { u32 bps = u64_get_bits(rmm_feat_reg0, RMI_FEATURE_REGISTER_0_NUM_BPS);
--
2.43.0