summaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/dbell.c
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/powerpc/kernel/dbell.c
Initial import
Diffstat (limited to 'arch/powerpc/kernel/dbell.c')
-rw-r--r--arch/powerpc/kernel/dbell.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/dbell.c b/arch/powerpc/kernel/dbell.c
new file mode 100644
index 000000000..2128f3a96
--- /dev/null
+++ b/arch/powerpc/kernel/dbell.c
@@ -0,0 +1,59 @@
+/*
+ * Author: Kumar Gala <galak@kernel.crashing.org>
+ *
+ * Copyright 2009 Freescale Semiconductor Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/smp.h>
+#include <linux/threads.h>
+#include <linux/hardirq.h>
+
+#include <asm/dbell.h>
+#include <asm/irq_regs.h>
+#include <asm/kvm_ppc.h>
+
+#ifdef CONFIG_SMP
+void doorbell_setup_this_cpu(void)
+{
+ unsigned long tag = mfspr(SPRN_DOORBELL_CPUTAG) & PPC_DBELL_TAG_MASK;
+
+ smp_muxed_ipi_set_data(smp_processor_id(), tag);
+}
+
+void doorbell_cause_ipi(int cpu, unsigned long data)
+{
+ /* Order previous accesses vs. msgsnd, which is treated as a store */
+ mb();
+ ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, data);
+}
+
+void doorbell_exception(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ irq_enter();
+
+ may_hard_irq_enable();
+
+ kvmppc_set_host_ipi(smp_processor_id(), 0);
+ __this_cpu_inc(irq_stat.doorbell_irqs);
+
+ smp_ipi_demux();
+
+ irq_exit();
+ set_irq_regs(old_regs);
+}
+#else /* CONFIG_SMP */
+void doorbell_exception(struct pt_regs *regs)
+{
+ printk(KERN_WARNING "Received doorbell on non-smp system\n");
+}
+#endif /* CONFIG_SMP */
+