patch-2.3.49 linux/arch/alpha/kernel/irq_srm.c

• Lines: 83
• Date: Mon Feb 28 14:54:30 2000
• Orig file: v2.3.48/linux/arch/alpha/kernel/irq_srm.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.48/linux/arch/alpha/kernel/irq_srm.c linux/arch/alpha/kernel/irq_srm.c
@@ -0,0 +1,82 @@
+/*
+ * Handle interrupts from the SRM, assuming no additional weirdness.
+ */
+
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/irq.h>
+
+#include <asm/machvec.h>
+#include <asm/dma.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.
+ */
+spinlock_t srm_irq_lock = SPIN_LOCK_UNLOCKED;
+
+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);
+}