1 files changed, 110 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/irq/imask.c b/arch/sh/kernel/cpu/irq/imask.c
new file mode 100644
index 0000000..baed9a5
--- /dev/null
+++ b/arch/sh/kernel/cpu/irq/imask.c
@@ -0,0 +1,110 @@
+/*
+ * arch/sh/kernel/cpu/irq/imask.c
+ *
+ * Copyright (C) 1999, 2000  Niibe Yutaka
+ *
+ * Simple interrupt handling using IMASK of SR register.
+ *
+ */
+/* NOTE: Will not work on level 15 */
+#include <linux/ptrace.h>
+#include <linux/errno.h>
+#include <linux/kernel_stat.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/spinlock.h>
+#include <linux/cache.h>
+#include <linux/irq.h>
+#include <asm/system.h>
+#include <asm/irq.h>
+
+/* Bitmap of IRQ masked */
+static unsigned long imask_mask = 0x7fff;
+static int interrupt_priority = 0;
+
+static void enable_imask_irq(unsigned int irq);
+static void disable_imask_irq(unsigned int irq);
+static void shutdown_imask_irq(unsigned int irq);
+static void mask_and_ack_imask(unsigned int);
+static void end_imask_irq(unsigned int irq);
+
+#define IMASK_PRIORITY	15
+
+static unsigned int startup_imask_irq(unsigned int irq)
+{
+	/* Nothing to do */
+	return 0; /* never anything pending */
+}
+
+static struct hw_interrupt_type imask_irq_type = {
+	.typename = "SR.IMASK",
+	.startup = startup_imask_irq,
+	.shutdown = shutdown_imask_irq,
+	.enable = enable_imask_irq,
+	.disable = disable_imask_irq,
+	.ack = mask_and_ack_imask,
+	.end = end_imask_irq
+};
+
+void static inline set_interrupt_registers(int ip)
+{
+	unsigned long __dummy;
+
+	asm volatile("ldc	%2, r6_bank\n\t"
+		     "stc	sr, %0\n\t"
+		     "and	#0xf0, %0\n\t"
+		     "shlr2	%0\n\t"
+		     "cmp/eq	#0x3c, %0\n\t"
+		     "bt/s	1f	! CLI-ed\n\t"
+		     " stc	sr, %0\n\t"
+		     "and	%1, %0\n\t"
+		     "or	%2, %0\n\t"
+		     "ldc	%0, sr\n"
+		     "1:"
+		     : "=&z" (__dummy)
+		     : "r" (~0xf0), "r" (ip << 4)
+		     : "t");
+}
+
+static void disable_imask_irq(unsigned int irq)
+{
+	clear_bit(irq, &imask_mask);
+	if (interrupt_priority < IMASK_PRIORITY - irq)
+		interrupt_priority = IMASK_PRIORITY - irq;
+
+	set_interrupt_registers(interrupt_priority);
+}
+
+static void enable_imask_irq(unsigned int irq)
+{
+	set_bit(irq, &imask_mask);
+	interrupt_priority = IMASK_PRIORITY - ffz(imask_mask);
+
+	set_interrupt_registers(interrupt_priority);
+}
+
+static void mask_and_ack_imask(unsigned int irq)
+{
+	disable_imask_irq(irq);
+}
+
+static void end_imask_irq(unsigned int irq)
+{
+	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+		enable_imask_irq(irq);
+}
+
+static void shutdown_imask_irq(unsigned int irq)
+{
+	/* Nothing to do */
+}
+
+void make_imask_irq(unsigned int irq)
+{
+	disable_irq_nosync(irq);
+	irq_desc[irq].handler = &imask_irq_type;
+	enable_irq(irq);
+}