summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/dbell.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/kernel/dbell.c')
-rw-r--r--arch/powerpc/kernel/dbell.c58
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);