Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / alpha / kernel / irq_srm.c

diff --git a/kernel/arch/alpha/kernel/irq_srm.c b/kernel/arch/alpha/kernel/irq_srm.c
new file mode 100644 (file)
index 0000000..a79fa30
--- /dev/null
+++ b/kernel/arch/alpha/kernel/irq_srm.c
@@ -0,0 +1,64 @@
+/*
+ * 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(struct irq_data *d)
+{
+       spin_lock(&srm_irq_lock);
+       cserve_ena(d->irq - 16);
+       spin_unlock(&srm_irq_lock);
+}
+
+static void
+srm_disable_irq(struct irq_data *d)
+{
+       spin_lock(&srm_irq_lock);
+       cserve_dis(d->irq - 16);
+       spin_unlock(&srm_irq_lock);
+}
+
+/* Handle interrupts from the SRM, assuming no additional weirdness.  */
+static struct irq_chip srm_irq_type = {
+       .name           = "SRM",
+       .irq_unmask     = srm_enable_irq,
+       .irq_mask       = srm_disable_irq,
+       .irq_mask_ack   = srm_disable_irq,
+};
+
+void __init
+init_srm_irqs(long max, unsigned long ignore_mask)
+{
+       long i;
+
+       if (NR_IRQS <= 16)
+               return;
+       for (i = 16; i < max; ++i) {
+               if (i < 64 && ((ignore_mask >> i) & 1))
+                       continue;
+               irq_set_chip_and_handler(i, &srm_irq_type, handle_level_irq);
+               irq_set_status_flags(i, IRQ_LEVEL);
+       }
+}
+
+void 
+srm_device_interrupt(unsigned long vector)
+{
+       int irq = (vector - 0x800) >> 4;
+       handle_irq(irq);
+}