KVM: PPC: Book3S HV: Prepare for host using hypervisor doorbells

POWER8 has support for hypervisor doorbell interrupts.  Though the
kernel doesn't use them for IPIs on the powernv platform yet, it
probably will in future, so this makes KVM cope gracefully if a
hypervisor doorbell interrupt arrives while in a guest.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/arch/powerpc/include/asm/kvm_asm.h b/arch/powerpc/include/asm/kvm_asm.h
index dba8fb2..c3815b1 100644 (file)
--- a/arch/powerpc/include/asm/kvm_asm.h
+++ b/arch/powerpc/include/asm/kvm_asm.h
@@ -96,6 +96,7 @@
 #define BOOK3S_INTERRUPT_H_DATA_STORAGE        0xe00
 #define BOOK3S_INTERRUPT_H_INST_STORAGE        0xe20
 #define BOOK3S_INTERRUPT_H_EMUL_ASSIST 0xe40
+#define BOOK3S_INTERRUPT_H_DOORBELL    0xe80
 #define BOOK3S_INTERRUPT_PERFMON       0xf00
 #define BOOK3S_INTERRUPT_ALTIVEC       0xf20
 #define BOOK3S_INTERRUPT_VSX           0xf40

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index d7f2ec6..216049f 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -651,6 +651,7 @@ static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu,
                r = RESUME_GUEST;
                break;
        case BOOK3S_INTERRUPT_EXTERNAL:
+       case BOOK3S_INTERRUPT_H_DOORBELL:
                vcpu->stat.ext_intr_exits++;
                r = RESUME_GUEST;
                break;

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 9e89c75..eae4ab9 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1997,10 +1997,17 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_207S)
 BEGIN_FTR_SECTION
        cmpwi   r6, 5                   /* privileged doorbell? */
        beq     0f
+       cmpwi   r6, 3                   /* hypervisor doorbell? */
+       beq     3f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
        li      r3, 1                   /* anything else, return 1 */
 0:     blr
 
+       /* hypervisor doorbell */
+3:     li      r12, BOOK3S_INTERRUPT_H_DOORBELL
+       li      r3, 1
+       blr
+
 /*
  * Determine what sort of external interrupt is pending (if any).
  * Returns: