KVM: PPC: booke: Added DECAR support

Added the decrementer auto-reload support. DECAR is readable
on e500v2/e500mc and later cpus.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

4 files changed, 13 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index dd783beb88b3..50ea12fd7bf5 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -418,7 +418,9 @@ struct kvm_vcpu_arch {
         ulong mcsrr1;
         ulong mcsr;
         u32 dec;
+#ifdef CONFIG_BOOKE
         u32 decar;
+#endif
         u32 tbl;
         u32 tbu;
         u32 tcr;
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 72f13f4a06e0..86681eec60b1 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1267,6 +1267,11 @@ void kvmppc_decrementer_func(unsigned long data)
 {
         struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
 
+        if (vcpu->arch.tcr & TCR_ARE) {
+                vcpu->arch.dec = vcpu->arch.decar;
+                kvmppc_emulate_dec(vcpu);
+        }
+
         kvmppc_set_tsr_bits(vcpu, TSR_DIS);
 }
 
diff --git a/arch/powerpc/kvm/booke_emulate.c b/arch/powerpc/kvm/booke_emulate.c
index 6c76397f2af4..9eb9809eb13e 100644
--- a/arch/powerpc/kvm/booke_emulate.c
+++ b/arch/powerpc/kvm/booke_emulate.c
@@ -129,6 +129,9 @@ int kvmppc_booke_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val)
                 kvmppc_set_tcr(vcpu, spr_val);
                 break;
 
+        case SPRN_DECAR:
+                vcpu->arch.decar = spr_val;
+                break;
         /*
          * Note: SPRG4-7 are user-readable.
          * These values are loaded into the real SPRGs when resuming the
diff --git a/arch/powerpc/kvm/e500_emulate.c b/arch/powerpc/kvm/e500_emulate.c
index 8b99e076dc81..e04b0ef55ce0 100644
--- a/arch/powerpc/kvm/e500_emulate.c
+++ b/arch/powerpc/kvm/e500_emulate.c
@@ -269,6 +269,9 @@ int kvmppc_core_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, ulong *spr_val)
                 *spr_val = vcpu->arch.shared->mas7_3 >> 32;
                 break;
 #endif
+        case SPRN_DECAR:
+                *spr_val = vcpu->arch.decar;
+                break;
         case SPRN_TLB0CFG:
                 *spr_val = vcpu->arch.tlbcfg[0];
                 break;