KVM: PPC: booke: Added DECAR support

Added the decrementer auto-reload support. DECAR is readable
on e500v2/e500mc and later cpus.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

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;

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);
 }
 

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

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;