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-rw-r--r--arch/mips/jazz/irq.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/arch/mips/jazz/irq.c b/arch/mips/jazz/irq.c
new file mode 100644
index 00000000000..0b608fa98d5
--- /dev/null
+++ b/arch/mips/jazz/irq.c
@@ -0,0 +1,100 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1992 Linus Torvalds
+ * Copyright (C) 1994 - 2001, 2003 Ralf Baechle
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+
+#include <asm/i8259.h>
+#include <asm/io.h>
+#include <asm/jazz.h>
+
+extern asmlinkage void jazz_handle_int(void);
+
+static DEFINE_SPINLOCK(r4030_lock);
+
+static void enable_r4030_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << (irq - JAZZ_PARALLEL_IRQ);
+ unsigned long flags;
+
+ spin_lock_irqsave(&r4030_lock, flags);
+ mask |= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
+ r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
+ spin_unlock_irqrestore(&r4030_lock, flags);
+}
+
+static unsigned int startup_r4030_irq(unsigned int irq)
+{
+ enable_r4030_irq(irq);
+ return 0; /* never anything pending */
+}
+
+#define shutdown_r4030_irq disable_r4030_irq
+
+void disable_r4030_irq(unsigned int irq)
+{
+ unsigned int mask = ~(1 << (irq - JAZZ_PARALLEL_IRQ));
+ unsigned long flags;
+
+ spin_lock_irqsave(&r4030_lock, flags);
+ mask &= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
+ r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
+ spin_unlock_irqrestore(&r4030_lock, flags);
+}
+
+#define mask_and_ack_r4030_irq disable_r4030_irq
+
+static void end_r4030_irq(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+ enable_r4030_irq(irq);
+}
+
+static struct hw_interrupt_type r4030_irq_type = {
+ "R4030",
+ startup_r4030_irq,
+ shutdown_r4030_irq,
+ enable_r4030_irq,
+ disable_r4030_irq,
+ mask_and_ack_r4030_irq,
+ end_r4030_irq,
+ NULL
+};
+
+void __init init_r4030_ints(void)
+{
+ int i;
+
+ for (i = JAZZ_PARALLEL_IRQ; i <= JAZZ_TIMER_IRQ; i++) {
+ irq_desc[i].status = IRQ_DISABLED;
+ irq_desc[i].action = 0;
+ irq_desc[i].depth = 1;
+ irq_desc[i].handler = &r4030_irq_type;
+ }
+
+ r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, 0);
+ r4030_read_reg16(JAZZ_IO_IRQ_SOURCE); /* clear pending IRQs */
+ r4030_read_reg32(JAZZ_R4030_INVAL_ADDR); /* clear error bits */
+}
+
+/*
+ * On systems with i8259-style interrupt controllers we assume for
+ * driver compatibility reasons interrupts 0 - 15 to be the i8259
+ * interrupts even if the hardware uses a different interrupt numbering.
+ */
+void __init arch_init_irq(void)
+{
+ set_except_vector(0, jazz_handle_int);
+
+ init_i8259_irqs(); /* Integrated i8259 */
+ init_r4030_ints();
+
+ change_c0_status(ST0_IM, IE_IRQ4 | IE_IRQ3 | IE_IRQ2 | IE_IRQ1);
+}