From 2d1d841bd44e24b58a3d3cc4fa793670aaa38fbf Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 18 Oct 2013 18:19:04 +0100 Subject: [PATCH] ARM: KVM: Fix MPIDR computing to support virtual clusters In order to be able to support more than 4 A7 or A15 CPUs, we need to fix the MPIDR computing to reflect the fact that both A15 and A7 can only exist in clusters of at most 4 CPUs. Fix the MPIDR computing to allow virtual clusters to be exposed to the guest. Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/coproc.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index a629f2c1d0f9..631e6bd0e05f 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -74,11 +74,13 @@ int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run) static void reset_mpidr(struct kvm_vcpu *vcpu, const struct coproc_reg *r) { /* - * Compute guest MPIDR. No need to mess around with different clusters - * but we read the 'U' bit from the underlying hardware directly. + * Compute guest MPIDR. We build a virtual cluster out of the + * vcpu_id, but we read the 'U' bit from the underlying + * hardware directly. */ - vcpu->arch.cp15[c0_MPIDR] = (read_cpuid_mpidr() & MPIDR_SMP_BITMASK) - | vcpu->vcpu_id; + vcpu->arch.cp15[c0_MPIDR] = ((read_cpuid_mpidr() & MPIDR_SMP_BITMASK) | + ((vcpu->vcpu_id >> 2) << MPIDR_LEVEL_BITS) | + (vcpu->vcpu_id & 3)); } /* TRM entries A7:4.3.31 A15:4.3.28 - RO WI */