arm/arm64: KVM: Implement PSCI 1.0 support

PSCI 1.0 can be trivially implemented by providing the FEATURES
call on top of PSCI 0.2 and returning 1.0 as the PSCI version.

We happily ignore everything else, as they are either optional or
are clarifications that do not require any additional change.

PSCI 1.0 is now the default until we decide to add a userspace
selection API.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

include/kvm/arm_psci.h

@@ -22,6 +22,9 @@
 
 #define KVM_ARM_PSCI_0_1	PSCI_VERSION(0, 1)
 #define KVM_ARM_PSCI_0_2	PSCI_VERSION(0, 2)
+#define KVM_ARM_PSCI_1_0	PSCI_VERSION(1, 0)
+
+#define KVM_ARM_PSCI_LATEST	KVM_ARM_PSCI_1_0
 
 int kvm_psci_version(struct kvm_vcpu *vcpu);
 int kvm_psci_call(struct kvm_vcpu *vcpu);

virt/kvm/arm/psci.c

@@ -234,7 +234,7 @@ static void kvm_psci_system_reset(struct kvm_vcpu *vcpu)
 int kvm_psci_version(struct kvm_vcpu *vcpu)
 {
 	if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
-		return KVM_ARM_PSCI_0_2;
+		return KVM_ARM_PSCI_LATEST;
 
 	return KVM_ARM_PSCI_0_1;
 }
@@ -313,6 +313,47 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
 	return ret;
 }
 
+static int kvm_psci_1_0_call(struct kvm_vcpu *vcpu)
+{
+	u32 psci_fn = smccc_get_function(vcpu);
+	u32 feature;
+	unsigned long val;
+	int ret = 1;
+
+	switch(psci_fn) {
+	case PSCI_0_2_FN_PSCI_VERSION:
+		val = KVM_ARM_PSCI_1_0;
+		break;
+	case PSCI_1_0_FN_PSCI_FEATURES:
+		feature = smccc_get_arg1(vcpu);
+		switch(feature) {
+		case PSCI_0_2_FN_PSCI_VERSION:
+		case PSCI_0_2_FN_CPU_SUSPEND:
+		case PSCI_0_2_FN64_CPU_SUSPEND:
+		case PSCI_0_2_FN_CPU_OFF:
+		case PSCI_0_2_FN_CPU_ON:
+		case PSCI_0_2_FN64_CPU_ON:
+		case PSCI_0_2_FN_AFFINITY_INFO:
+		case PSCI_0_2_FN64_AFFINITY_INFO:
+		case PSCI_0_2_FN_MIGRATE_INFO_TYPE:
+		case PSCI_0_2_FN_SYSTEM_OFF:
+		case PSCI_0_2_FN_SYSTEM_RESET:
+		case PSCI_1_0_FN_PSCI_FEATURES:
+			val = 0;
+			break;
+		default:
+			val = PSCI_RET_NOT_SUPPORTED;
+			break;
+		}
+		break;
+	default:
+		return kvm_psci_0_2_call(vcpu);
+	}
+
+	smccc_set_retval(vcpu, val, 0, 0, 0);
+	return ret;
+}
+
 static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
 {
 	struct kvm *kvm = vcpu->kvm;
@@ -355,6 +396,8 @@ static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
 int kvm_psci_call(struct kvm_vcpu *vcpu)
 {
 	switch (kvm_psci_version(vcpu)) {
+	case KVM_ARM_PSCI_1_0:
+		return kvm_psci_1_0_call(vcpu);
 	case KVM_ARM_PSCI_0_2:
 		return kvm_psci_0_2_call(vcpu);
 	case KVM_ARM_PSCI_0_1: