KVM: PPC: Book3SHV: Enable support for ISA v3.1 guests

Adds support for emulating ISAv3.1 guests by adding the appropriate PCR
and FSCR bits.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

arch/powerpc/include/asm/reg.h

@@ -1354,6 +1354,7 @@
 #define PVR_ARCH_206p	0x0f100003
 #define PVR_ARCH_207	0x0f000004
 #define PVR_ARCH_300	0x0f000005
+#define PVR_ARCH_31	0x0f000006
 
 /* Macros for setting and retrieving special purpose registers */
 #ifndef __ASSEMBLY__

arch/powerpc/kvm/book3s_hv.c

@@ -342,13 +342,18 @@ static void kvmppc_set_pvr_hv(struct kvm_vcpu *vcpu, u32 pvr)
 	vcpu->arch.pvr = pvr;
 }
 
+/* Dummy value used in computing PCR value below */
+#define PCR_ARCH_31    (PCR_ARCH_300 << 1)
+
 static int kvmppc_set_arch_compat(struct kvm_vcpu *vcpu, u32 arch_compat)
 {
 	unsigned long host_pcr_bit = 0, guest_pcr_bit = 0;
 	struct kvmppc_vcore *vc = vcpu->arch.vcore;
 
 	/* We can (emulate) our own architecture version and anything older */
-	if (cpu_has_feature(CPU_FTR_ARCH_300))
+	if (cpu_has_feature(CPU_FTR_ARCH_31))
+		host_pcr_bit = PCR_ARCH_31;
+	else if (cpu_has_feature(CPU_FTR_ARCH_300))
 		host_pcr_bit = PCR_ARCH_300;
 	else if (cpu_has_feature(CPU_FTR_ARCH_207S))
 		host_pcr_bit = PCR_ARCH_207;
@@ -374,6 +379,9 @@ static int kvmppc_set_arch_compat(struct kvm_vcpu *vcpu, u32 arch_compat)
 		case PVR_ARCH_300:
 			guest_pcr_bit = PCR_ARCH_300;
 			break;
+		case PVR_ARCH_31:
+			guest_pcr_bit = PCR_ARCH_31;
+			break;
 		default:
 			return -EINVAL;
 		}
@@ -2318,7 +2326,7 @@ static int kvmppc_core_vcpu_create_hv(struct kvm_vcpu *vcpu)
 	 * to trap and then we emulate them.
 	 */
 	vcpu->arch.hfscr = HFSCR_TAR | HFSCR_EBB | HFSCR_PM | HFSCR_BHRB |
-		HFSCR_DSCR | HFSCR_VECVSX | HFSCR_FP;
+		HFSCR_DSCR | HFSCR_VECVSX | HFSCR_FP | HFSCR_PREFIX;
 	if (cpu_has_feature(CPU_FTR_HVMODE)) {
 		vcpu->arch.hfscr &= mfspr(SPRN_HFSCR);
 		if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST))