From:   Steven Price <steven.price@arm.com>
To:     kvm@vger.kernel.org, kvmarm@lists.linux.dev
Cc:     Steven Price <steven.price@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Marc Zyngier <maz@kernel.org>, Will Deacon <will@kernel.org>,
        James Morse <james.morse@arm.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Zenghui Yu <yuzenghui@huawei.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Joey Gouly <joey.gouly@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Christoffer Dall <christoffer.dall@arm.com>,
        Fuad Tabba <tabba@google.com>, linux-coco@lists.linux.dev
Subject: [RFC PATCH 20/28] KVM: arm64: Handle Realm PSCI requests
Date:   Fri, 27 Jan 2023 11:29:24 +0000
Message-Id: <20230127112932.38045-21-steven.price@arm.com>
In-Reply-To: <20230127112932.38045-1-steven.price@arm.com>
References: <20230127112248.136810-1-suzuki.poulose@arm.com>
 <20230127112932.38045-1-steven.price@arm.com>
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The RMM needs to be informed of the target REC when a PSCI call is made
with an MPIDR argument.

Signed-off-by: Steven Price <steven.price@arm.com>
---
 arch/arm64/include/asm/kvm_rme.h |  1 +
 arch/arm64/kvm/psci.c            | 23 +++++++++++++++++++++++
 arch/arm64/kvm/rme.c             | 13 +++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/asm/kvm_rme.h
index 303e4a5e5704..2254e28c855e 100644
--- a/arch/arm64/include/asm/kvm_rme.h
+++ b/arch/arm64/include/asm/kvm_rme.h
@@ -65,6 +65,7 @@ int realm_map_non_secure(struct realm *realm,
 int realm_set_ipa_state(struct kvm_vcpu *vcpu,
 			unsigned long addr, unsigned long end,
 			unsigned long ripas);
+int realm_psci_complete(struct kvm_vcpu *calling, struct kvm_vcpu *target);
 
 #define RME_RTT_BLOCK_LEVEL	2
 #define RME_RTT_MAX_LEVEL	3
diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c
index 7fbc4c1b9df0..e2061cab9b26 100644
--- a/arch/arm64/kvm/psci.c
+++ b/arch/arm64/kvm/psci.c
@@ -76,6 +76,10 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
 	 */
 	if (!vcpu)
 		return PSCI_RET_INVALID_PARAMS;
+
+	if (vcpu_is_rec(vcpu))
+		realm_psci_complete(source_vcpu, vcpu);
+
 	if (!kvm_arm_vcpu_stopped(vcpu)) {
 		if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1)
 			return PSCI_RET_ALREADY_ON;
@@ -135,6 +139,25 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu)
 	/* Ignore other bits of target affinity */
 	target_affinity &= target_affinity_mask;
 
+	if (vcpu_is_rec(vcpu)) {
+		struct kvm_vcpu *target_vcpu;
+
+		/* RMM supports only zero affinity level */
+		if (lowest_affinity_level != 0)
+			return PSCI_RET_INVALID_PARAMS;
+
+		target_vcpu = kvm_mpidr_to_vcpu(kvm, target_affinity);
+		if (!target_vcpu)
+			return PSCI_RET_INVALID_PARAMS;
+
+		/*
+		 * Provide the references of running and target RECs to the RMM
+		 * so that the RMM can complete the PSCI request.
+		 */
+		realm_psci_complete(vcpu, target_vcpu);
+		return PSCI_RET_SUCCESS;
+	}
+
 	/*
 	 * If one or more VCPU matching target affinity are running
 	 * then ON else OFF
diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c
index 3d46191798e5..6ac50481a138 100644
--- a/arch/arm64/kvm/rme.c
+++ b/arch/arm64/kvm/rme.c
@@ -126,6 +126,19 @@ static void free_delegated_page(struct realm *realm, phys_addr_t phys)
 	free_page((unsigned long)phys_to_virt(phys));
 }
 
+int realm_psci_complete(struct kvm_vcpu *calling, struct kvm_vcpu *target)
+{
+	int ret;
+
+	ret = rmi_psci_complete(virt_to_phys(calling->arch.rec.rec_page),
+				virt_to_phys(target->arch.rec.rec_page));
+
+	if (ret)
+		return -EINVAL;
+
+	return 0;
+}
+
 static void realm_destroy_undelegate_range(struct realm *realm,
 					   unsigned long ipa,
 					   unsigned long addr,
-- 
2.34.1