From: Oliver Upton <oliver.upton@linux.dev>

Implement support for PSCI CPU_SUSPEND, leveraging in-kernel suspend
emulation (i.e. a WFI state). Eagerly resume the vCPU for any wakeup
event.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 kvm-cpu.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/kvm-cpu.c b/kvm-cpu.c
index 7362f2e9..d718ef60 100644
--- a/kvm-cpu.c
+++ b/kvm-cpu.c
@@ -143,6 +143,16 @@ void kvm_cpu__run_on_all_cpus(struct kvm *kvm, struct kvm_cpu_task *task)
 	mutex_unlock(&task_lock);
 }
 
+static void handle_wakeup(struct kvm_cpu *vcpu)
+{
+	struct kvm_mp_state mp_state = {
+		.mp_state = KVM_MP_STATE_RUNNABLE,
+	};
+
+	if (ioctl(vcpu->vcpu_fd, KVM_SET_MP_STATE, &mp_state))
+		die_perror("KVM_SET_MP_STATE failed");
+}
+
 int kvm_cpu__start(struct kvm_cpu *cpu)
 {
 	sigset_t sigset;
@@ -236,6 +246,9 @@ int kvm_cpu__start(struct kvm_cpu *cpu)
 				 */
 				kvm__reboot(cpu->kvm);
 				goto exit_kvm;
+			case KVM_SYSTEM_EVENT_WAKEUP:
+				handle_wakeup(cpu);
+				break;
 			};
 			break;
 		default: {
-- 
2.43.0