KVM: arm64: Add support for PSCI v1.2 and v1.3

As with PSCI v1.1 in commit 512865d ("KVM: arm64: Bump guest PSCI
version to 1.1"), expose v1.3 to the guest by default. The SYSTEM_OFF2
call which is exposed by doing so is compatible for userspace because
it's just a new flag in the event that KVM raises, in precisely the same
way that SYSTEM_RESET2 was compatible when v1.1 was enabled by default.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Miguel Luis <miguel.luis@oracle.com>
Link: https://lore.kernel.org/r/20241019172459.2241939-4-dwmw2@infradead.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

Author: dwmw2

arch/arm64/kvm/hypercalls.c

@@ -575,6 +575,8 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 		case KVM_ARM_PSCI_0_2:
 		case KVM_ARM_PSCI_1_0:
 		case KVM_ARM_PSCI_1_1:
+		case KVM_ARM_PSCI_1_2:
+		case KVM_ARM_PSCI_1_3:
 			if (!wants_02)
 				return -EINVAL;
 			vcpu->kvm->arch.psci_version = val;

arch/arm64/kvm/psci.c

@@ -328,7 +328,7 @@ static int kvm_psci_1_x_call(struct kvm_vcpu *vcpu, u32 minor)
 
 	switch(psci_fn) {
 	case PSCI_0_2_FN_PSCI_VERSION:
-		val = minor == 0 ? KVM_ARM_PSCI_1_0 : KVM_ARM_PSCI_1_1;
+		val = PSCI_VERSION(1, minor);
 		break;
 	case PSCI_1_0_FN_PSCI_FEATURES:
 		arg = smccc_get_arg1(vcpu);
@@ -487,6 +487,10 @@ int kvm_psci_call(struct kvm_vcpu *vcpu)
 	}
 
 	switch (version) {
+	case KVM_ARM_PSCI_1_3:
+		return kvm_psci_1_x_call(vcpu, 3);
+	case KVM_ARM_PSCI_1_2:
+		return kvm_psci_1_x_call(vcpu, 2);
 	case KVM_ARM_PSCI_1_1:
 		return kvm_psci_1_x_call(vcpu, 1);
 	case KVM_ARM_PSCI_1_0:

include/kvm/arm_psci.h

@@ -14,8 +14,10 @@
 #define KVM_ARM_PSCI_0_2	PSCI_VERSION(0, 2)
 #define KVM_ARM_PSCI_1_0	PSCI_VERSION(1, 0)
 #define KVM_ARM_PSCI_1_1	PSCI_VERSION(1, 1)
+#define KVM_ARM_PSCI_1_2	PSCI_VERSION(1, 2)
+#define KVM_ARM_PSCI_1_3	PSCI_VERSION(1, 3)
 
-#define KVM_ARM_PSCI_LATEST	KVM_ARM_PSCI_1_1
+#define KVM_ARM_PSCI_LATEST	KVM_ARM_PSCI_1_3
 
 static inline int kvm_psci_version(struct kvm_vcpu *vcpu)
 {