1 files changed, 79 insertions, 0 deletions

diff --git a/arch/alpha/kernel/irq_srm.c b/arch/alpha/kernel/irq_srm.c
new file mode 100644
index 000000000000..0a87e466918c
--- /dev/null
+++ b/arch/alpha/kernel/irq_srm.c
@@ -0,0 +1,79 @@
+/*
+ * Handle interrupts from the SRM, assuming no additional weirdness.
+ */
+
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/irq.h>
+
+#include "proto.h"
+#include "irq_impl.h"
+
+
+/*
+ * Is the palcode SMP safe? In other words: can we call cserve_ena/dis
+ * at the same time in multiple CPUs? To be safe I added a spinlock
+ * but it can be removed trivially if the palcode is robust against smp.
+ */
+DEFINE_SPINLOCK(srm_irq_lock);
+
+static inline void
+srm_enable_irq(unsigned int irq)
+{
+        spin_lock(&srm_irq_lock);
+        cserve_ena(irq - 16);
+        spin_unlock(&srm_irq_lock);
+}
+
+static void
+srm_disable_irq(unsigned int irq)
+{
+        spin_lock(&srm_irq_lock);
+        cserve_dis(irq - 16);
+        spin_unlock(&srm_irq_lock);
+}
+
+static unsigned int
+srm_startup_irq(unsigned int irq)
+{
+        srm_enable_irq(irq);
+        return 0;
+}
+
+static void
+srm_end_irq(unsigned int irq)
+{
+        if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+                srm_enable_irq(irq);
+}
+
+/* Handle interrupts from the SRM, assuming no additional weirdness.  */
+static struct hw_interrupt_type srm_irq_type = {
+        .typename       = "SRM",
+        .startup        = srm_startup_irq,
+        .shutdown       = srm_disable_irq,
+        .enable         = srm_enable_irq,
+        .disable        = srm_disable_irq,
+        .ack            = srm_disable_irq,
+        .end            = srm_end_irq,
+};
+
+void __init
+init_srm_irqs(long max, unsigned long ignore_mask)
+{
+        long i;
+
+        for (i = 16; i < max; ++i) {
+                if (i < 64 && ((ignore_mask >> i) & 1))
+                        continue;
+                irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
+                irq_desc[i].handler = &srm_irq_type;
+        }
+}
+
+void 
+srm_device_interrupt(unsigned long vector, struct pt_regs * regs)
+{
+        int irq = (vector - 0x800) >> 4;
+        handle_irq(irq, regs);
+}