powerpc: Define new SRR1 bits for a ISA v3.1

Add the BOUNDARY SRR1 bit definition for when the cause of an
alignment exception is a prefixed instruction that crosses a 64-byte
boundary. Add the PREFIXED SRR1 bit definition for exceptions caused
by prefixed instructions.

Bit 35 of SRR1 is called SRR1_ISI_N_OR_G. This name comes from it
being used to indicate that an ISI was due to the access being no-exec
or guarded. ISA v3.1 adds another purpose. It is also set if there is
an access in a cache-inhibited location for prefixed instruction.
Rename from SRR1_ISI_N_OR_G to SRR1_ISI_N_G_OR_CIP.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-23-jniethe5@gmail.com

arch/powerpc/include/asm/reg.h

@@ -762,7 +762,7 @@
 #endif
 
 #define   SRR1_ISI_NOPT		0x40000000 /* ISI: Not found in hash */
-#define   SRR1_ISI_N_OR_G	0x10000000 /* ISI: Access is no-exec or G */
+#define   SRR1_ISI_N_G_OR_CIP	0x10000000 /* ISI: Access is no-exec or G or CI for a prefixed instruction */
 #define   SRR1_ISI_PROT		0x08000000 /* ISI: Other protection fault */
 #define   SRR1_WAKEMASK		0x00380000 /* reason for wakeup */
 #define   SRR1_WAKEMASK_P8	0x003c0000 /* reason for wakeup on POWER8 and 9 */
@@ -789,6 +789,8 @@
 #define   SRR1_PROGADDR		0x00010000 /* SRR0 contains subsequent addr */
 
 #define   SRR1_MCE_MCP		0x00080000 /* Machine check signal caused interrupt */
+#define   SRR1_BOUNDARY		0x10000000 /* Prefixed instruction crosses 64-byte boundary */
+#define   SRR1_PREFIXED		0x20000000 /* Exception caused by prefixed instruction */
 
 #define SPRN_HSRR0	0x13A	/* Save/Restore Register 0 */
 #define SPRN_HSRR1	0x13B	/* Save/Restore Register 1 */

arch/powerpc/kvm/book3s_hv_nested.c

@@ -1182,7 +1182,7 @@ static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
 		} else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
 			/* Can we execute? */
 			if (!gpte_p->may_execute) {
-				flags |= SRR1_ISI_N_OR_G;
+				flags |= SRR1_ISI_N_G_OR_CIP;
 				goto forward_to_l1;
 			}
 		} else {

arch/powerpc/kvm/book3s_hv_rm_mmu.c

@@ -1240,7 +1240,7 @@ long kvmppc_hpte_hv_fault(struct kvm_vcpu *vcpu, unsigned long addr,
 	status &= ~DSISR_NOHPTE;	/* DSISR_NOHPTE == SRR1_ISI_NOPT */
 	if (!data) {
 		if (gr & (HPTE_R_N | HPTE_R_G))
-			return status | SRR1_ISI_N_OR_G;
+			return status | SRR1_ISI_N_G_OR_CIP;
 		if (!hpte_read_permission(pp, slb_v & key))
 			return status | SRR1_ISI_PROT;
 	} else if (status & DSISR_ISSTORE) {