arm/arm64: KVM: rework MPIDR assignment and add accessors

The virtual MPIDR registers (containing topology information) for the
guest are currently mapped linearily to the vcpu_id. Improve this
mapping for arm64 by using three levels to not artificially limit the
number of vCPUs.
To help this, change and rename the kvm_vcpu_get_mpidr() function to
mask off the non-affinity bits in the MPIDR register.
Also add an accessor to later allow easier access to a vCPU with a
given MPIDR. Use this new accessor in the PSCI emulation.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 74603a09ee76..a7b94ecba0d8 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -1075,6 +1075,19 @@ static void check_kvm_target_cpu(void *ret)
         *(int *)ret = kvm_target_cpu();
 }
 
+struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
+{
+        struct kvm_vcpu *vcpu;
+        int i;
+
+        mpidr &= MPIDR_HWID_BITMASK;
+        kvm_for_each_vcpu(i, vcpu, kvm) {
+                if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
+                        return vcpu;
+        }
+        return NULL;
+}
+
 /**
  * Initialize Hyp-mode and memory mappings on all CPUs.
  */