Implement support for PSCI AFFINITY_INFO by iteratively searching all of
the vCPUs in a VM for those that match the specified affinity. Pause the
VM to avoid racing against other PSCI calls in the system that might
change the power state of the vCPUs.
Signed-off-by: Oliver Upton <oliver.upton@xxxxxxxxx>
---
arm/aarch64/include/kvm/kvm-cpu-arch.h | 12 +++++-
arm/aarch64/psci.c | 59 ++++++++++++++++++++++++++
2 files changed, 70 insertions(+), 1 deletion(-)
diff --git a/arm/aarch64/include/kvm/kvm-cpu-arch.h b/arm/aarch64/include/kvm/kvm-cpu-arch.h
index 264d0016f7db..5dced04d4035 100644
--- a/arm/aarch64/include/kvm/kvm-cpu-arch.h
+++ b/arm/aarch64/include/kvm/kvm-cpu-arch.h
@@ -5,12 +5,22 @@
#include "arm-common/kvm-cpu-arch.h"
-#define ARM_MPIDR_HWID_BITMASK 0xFF00FFFFFFUL
#define ARM_CPU_ID 3, 0, 0, 0
#define ARM_CPU_ID_MPIDR 5
#define ARM_CPU_CTRL 3, 0, 1, 0
#define ARM_CPU_CTRL_SCTLR_EL1 0
+#define ARM_MPIDR_HWID_BITMASK 0xFF00FFFFFFUL
+#define ARM_MPIDR_LEVEL_BITS_SHIFT 3
+#define ARM_MPIDR_LEVEL_BITS (1 << ARM_MPIDR_LEVEL_BITS_SHIFT)
+#define ARM_MPIDR_LEVEL_MASK ((1 << ARM_MPIDR_LEVEL_BITS) - 1)
+
+#define ARM_MPIDR_LEVEL_SHIFT(level) \
+ (((1 << level) >> 1) << ARM_MPIDR_LEVEL_BITS_SHIFT)
+
+#define ARM_MPIDR_AFFINITY_LEVEL(mpidr, level) \
+ ((mpidr >> ARM_MPIDR_LEVEL_SHIFT(level)) & ARM_MPIDR_LEVEL_MASK)
+
static inline __u64 __core_reg_id(__u64 offset)
{
__u64 id = KVM_REG_ARM64 | KVM_REG_ARM_CORE | offset;
diff --git a/arm/aarch64/psci.c b/arm/aarch64/psci.c
index 254e16e7985d..ac49d7aa8f22 100644
--- a/arm/aarch64/psci.c
+++ b/arm/aarch64/psci.c
@@ -6,6 +6,16 @@
#include <linux/psci.h>
#include <linux/types.h>
+#define AFFINITY_MASK(level) ~((0x1UL << ((level) * ARM_MPIDR_LEVEL_BITS)) - 1)
+
+static unsigned long psci_affinity_mask(unsigned long affinity_level)
+{
+ if (affinity_level <= 3)
+ return ARM_MPIDR_HWID_BITMASK & AFFINITY_MASK(affinity_level);
+
+ return 0;
+}
+
static void psci_features(struct kvm_cpu *vcpu, struct arm_smccc_res *res)
{
u32 arg = smccc_get_arg(vcpu, 1);
@@ -20,6 +30,8 @@ static void psci_features(struct kvm_cpu *vcpu, struct arm_smccc_res *res)
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 ARM_SMCCC_VERSION_FUNC_ID:
res->a0 = PSCI_RET_SUCCESS;
break;
@@ -111,6 +123,49 @@ out_continue:
kvm_cpu__continue_vm(vcpu);
}
+static void affinity_info(struct kvm_cpu *vcpu, struct arm_smccc_res *res)
+{
+ u64 target_affinity = smccc_get_arg(vcpu, 1);
+ u64 lowest_level = smccc_get_arg(vcpu, 2);
+ u64 mpidr_mask = psci_affinity_mask(lowest_level);
+ struct kvm *kvm = vcpu->kvm;
+ bool matched = false;
+ int i;
+
+ if (!psci_valid_affinity(target_affinity) || lowest_level > 3) {
+ res->a0 = PSCI_RET_INVALID_PARAMS;
+ return;
+ }
+
+ kvm_cpu__pause_vm(vcpu);
+
+ for (i = 0; i < kvm->nrcpus; i++) {
+ struct kvm_cpu *tmp = kvm->cpus[i];
+ u64 mpidr = kvm_cpu__get_vcpu_mpidr(tmp);
+ struct kvm_mp_state mp_state;
+
+ if ((mpidr & mpidr_mask) != target_affinity)
+ continue;
+
+ if (ioctl(tmp->vcpu_fd, KVM_GET_MP_STATE, &mp_state))
+ die_perror("KVM_GET_MP_STATE failed");
+
+ if (mp_state.mp_state != KVM_MP_STATE_STOPPED) {
+ res->a0 = PSCI_0_2_AFFINITY_LEVEL_ON;
+ goto out_continue;
+ }
+
+ matched = true;
+ }
+
+ if (matched)
+ res->a0 = PSCI_0_2_AFFINITY_LEVEL_OFF;
+ else
+ res->a0 = PSCI_RET_INVALID_PARAMS;
+out_continue:
+ kvm_cpu__continue_vm(vcpu);
+}
+
void handle_psci(struct kvm_cpu *vcpu, struct arm_smccc_res *res)
{
switch (vcpu->kvm_run->hypercall.nr) {
@@ -131,6 +186,10 @@ void handle_psci(struct kvm_cpu *vcpu, struct arm_smccc_res *res)
case PSCI_0_2_FN64_CPU_ON:
cpu_on(vcpu, res);
break;
+ case PSCI_0_2_FN_AFFINITY_INFO:
+ case PSCI_0_2_FN64_AFFINITY_INFO:
+ affinity_info(vcpu, res);
+ break;
default:
res->a0 = PSCI_RET_NOT_SUPPORTED;
}
--
2.41.0.585.gd2178a4bd4-goog
