4 files changed, 42 insertions, 3 deletions

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 0d4531aa2052..dff79798903d 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -649,9 +649,10 @@
 #define   SRR1_ISI_N_OR_G       0x10000000 /* ISI: Access is no-exec or G */
 #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 */
+#define   SRR1_WAKEMASK_P8      0x003c0000 /* reason for wakeup on POWER8 and 9 */
 #define   SRR1_WAKESYSERR       0x00300000 /* System error */
 #define   SRR1_WAKEEE           0x00200000 /* External interrupt */
+#define   SRR1_WAKEHVI          0x00240000 /* Hypervisor Virtualization Interrupt (P9) */
 #define   SRR1_WAKEMT           0x00280000 /* mtctrl */
 #define   SRR1_WAKEHMI          0x00280000 /* Hypervisor maintenance */
 #define   SRR1_WAKEDEC          0x00180000 /* Decrementer interrupt */
diff --git a/arch/powerpc/include/asm/xics.h b/arch/powerpc/include/asm/xics.h
index f0b238516e9b..e0b9e576905a 100644
--- a/arch/powerpc/include/asm/xics.h
+++ b/arch/powerpc/include/asm/xics.h
@@ -44,6 +44,7 @@ static inline int icp_hv_init(void) { return -ENODEV; }
 
 #ifdef CONFIG_PPC_POWERNV
 extern int icp_opal_init(void);
+extern void icp_opal_flush_interrupt(void);
 #else
 static inline int icp_opal_init(void) { return -ENODEV; }
 #endif
diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index c789258ae1e1..eec0e8d0454d 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -155,8 +155,10 @@ static void pnv_smp_cpu_kill_self(void)
                 wmask = SRR1_WAKEMASK_P8;
 
         idle_states = pnv_get_supported_cpuidle_states();
+
         /* We don't want to take decrementer interrupts while we are offline,
-         * so clear LPCR:PECE1. We keep PECE2 enabled.
+         * so clear LPCR:PECE1. We keep PECE2 (and LPCR_PECE_HVEE on P9)
+         * enabled as to let IPIs in.
          */
         mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
 
@@ -206,8 +208,12 @@ static void pnv_smp_cpu_kill_self(void)
                  * contains 0.
                  */
                 if (((srr1 & wmask) == SRR1_WAKEEE) ||
+                    ((srr1 & wmask) == SRR1_WAKEHVI) ||
                     (local_paca->irq_happened & PACA_IRQ_EE)) {
-                        icp_native_flush_interrupt();
+                        if (cpu_has_feature(CPU_FTR_ARCH_300))
+                                icp_opal_flush_interrupt();
+                        else
+                                icp_native_flush_interrupt();
                 } else if ((srr1 & wmask) == SRR1_WAKEHDBELL) {
                         unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
                         asm volatile(PPC_MSGCLR(%0) : : "r" (msg));
@@ -221,6 +227,8 @@ static void pnv_smp_cpu_kill_self(void)
                 if (srr1 && !generic_check_cpu_restart(cpu))
                         DBG("CPU%d Unexpected exit while offline !\n", cpu);
         }
+
+        /* Re-enable decrementer interrupts */
         mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1);
         DBG("CPU%d coming online...\n", cpu);
 }
diff --git a/arch/powerpc/sysdev/xics/icp-opal.c b/arch/powerpc/sysdev/xics/icp-opal.c
index 60c57657c772..c96c0cb95d87 100644
--- a/arch/powerpc/sysdev/xics/icp-opal.c
+++ b/arch/powerpc/sysdev/xics/icp-opal.c
@@ -132,6 +132,35 @@ static irqreturn_t icp_opal_ipi_action(int irq, void *dev_id)
         return smp_ipi_demux();
 }
 
+/*
+ * Called when an interrupt is received on an off-line CPU to
+ * clear the interrupt, so that the CPU can go back to nap mode.
+ */
+void icp_opal_flush_interrupt(void)
+{
+        unsigned int xirr;
+        unsigned int vec;
+
+        do {
+                xirr = icp_opal_get_xirr();
+                vec = xirr & 0x00ffffff;
+                if (vec == XICS_IRQ_SPURIOUS)
+                        break;
+                if (vec == XICS_IPI) {
+                        /* Clear pending IPI */
+                        int cpu = smp_processor_id();
+                        kvmppc_set_host_ipi(cpu, 0);
+                        opal_int_set_mfrr(get_hard_smp_processor_id(cpu), 0xff);
+                } else {
+                        pr_err("XICS: hw interrupt 0x%x to offline cpu, "
+                               "disabling\n", vec);
+                        xics_mask_unknown_vec(vec);
+                }
+
+                /* EOI the interrupt */
+        } while (opal_int_eoi(xirr) > 0);
+}
+
 #endif /* CONFIG_SMP */
 
 static const struct icp_ops icp_opal_ops = {