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Diffstat (limited to 'arch/sh/kernel/cpu/irq_imask.c')
-rw-r--r--arch/sh/kernel/cpu/irq_imask.c116
1 files changed, 116 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 000000000000..f76901e732fb
--- /dev/null
+++ b/arch/sh/kernel/cpu/irq_imask.c
@@ -0,0 +1,116 @@
+/* $Id: irq_imask.c,v 1.1.2.1 2002/11/17 10:53:43 mrbrown Exp $
+ *
+ * linux/arch/sh/kernel/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 <asm/system.h>
+#include <asm/irq.h>
+
+#include <linux/spinlock.h>
+#include <linux/cache.h>
+#include <linux/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 = {
+ "SR.IMASK",
+ startup_imask_irq,
+ shutdown_imask_irq,
+ enable_imask_irq,
+ disable_imask_irq,
+ mask_and_ack_imask,
+ 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);
+}