1 files changed, 51 insertions, 7 deletions

diff --git a/arch/powerpc/kernel/dbell.c b/arch/powerpc/kernel/dbell.c
index 2128f3a96c32..b6fe883b1016 100644
--- a/arch/powerpc/kernel/dbell.c
+++ b/arch/powerpc/kernel/dbell.c
@@ -20,18 +20,60 @@
 #include <asm/kvm_ppc.h>
 
 #ifdef CONFIG_SMP
-void doorbell_setup_this_cpu(void)
+
+/*
+ * Doorbells must only be used if CPU_FTR_DBELL is available.
+ * msgsnd is used in HV, and msgsndp is used in !HV.
+ *
+ * These should be used by platform code that is aware of restrictions.
+ * Other arch code should use ->cause_ipi.
+ *
+ * doorbell_global_ipi() sends a dbell to any target CPU.
+ * Must be used only by architectures that address msgsnd target
+ * by PIR/get_hard_smp_processor_id.
+ */
+void doorbell_global_ipi(int cpu)
 {
-	unsigned long tag = mfspr(SPRN_DOORBELL_CPUTAG) & PPC_DBELL_TAG_MASK;
+	u32 tag = get_hard_smp_processor_id(cpu);
 
-	smp_muxed_ipi_set_data(smp_processor_id(), tag);
+	kvmppc_set_host_ipi(cpu, 1);
+	/* Order previous accesses vs. msgsnd, which is treated as a store */
+	ppc_msgsnd_sync();
+	ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, tag);
 }
 
-void doorbell_cause_ipi(int cpu, unsigned long data)
+/*
+ * doorbell_core_ipi() sends a dbell to a target CPU in the same core.
+ * Must be used only by architectures that address msgsnd target
+ * by TIR/cpu_thread_in_core.
+ */
+void doorbell_core_ipi(int cpu)
 {
+	u32 tag = cpu_thread_in_core(cpu);
+
+	kvmppc_set_host_ipi(cpu, 1);
 	/* Order previous accesses vs. msgsnd, which is treated as a store */
-	mb();
-	ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, data);
+	ppc_msgsnd_sync();
+	ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, tag);
+}
+
+/*
+ * Attempt to cause a core doorbell if destination is on the same core.
+ * Returns 1 on success, 0 on failure.
+ */
+int doorbell_try_core_ipi(int cpu)
+{
+	int this_cpu = get_cpu();
+	int ret = 0;
+
+	if (cpumask_test_cpu(cpu, cpu_sibling_mask(this_cpu))) {
+		doorbell_core_ipi(cpu);
+		ret = 1;
+	}
+
+	put_cpu();
+
+	return ret;
 }
 
 void doorbell_exception(struct pt_regs *regs)
@@ -40,12 +82,14 @@ void doorbell_exception(struct pt_regs *regs)
 
 	irq_enter();
 
+	ppc_msgsync();
+
 	may_hard_irq_enable();
 
 	kvmppc_set_host_ipi(smp_processor_id(), 0);
 	__this_cpu_inc(irq_stat.doorbell_irqs);
 
-	smp_ipi_demux();
+	smp_ipi_demux_relaxed(); /* already performed the barrier */
 
 	irq_exit();
 	set_irq_regs(old_regs);