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-rw-r--r--arch/mips/cobalt/irq.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/mips/cobalt/irq.c b/arch/mips/cobalt/irq.c
new file mode 100644
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+++ b/arch/mips/cobalt/irq.c
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+/*
+ * IRQ vector handles
+ *
+ * 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) 1995, 1996, 1997, 2003 by Ralf Baechle
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+
+#include <asm/i8259.h>
+#include <asm/irq_cpu.h>
+#include <asm/gt64120.h>
+#include <asm/ptrace.h>
+
+#include <asm/cobalt/cobalt.h>
+
+extern void cobalt_handle_int(void);
+
+/*
+ * We have two types of interrupts that we handle, ones that come in through
+ * the CPU interrupt lines, and ones that come in on the via chip. The CPU
+ * mappings are:
+ *
+ * 16, - Software interrupt 0 (unused) IE_SW0
+ * 17 - Software interrupt 1 (unused) IE_SW0
+ * 18 - Galileo chip (timer) IE_IRQ0
+ * 19 - Tulip 0 + NCR SCSI IE_IRQ1
+ * 20 - Tulip 1 IE_IRQ2
+ * 21 - 16550 UART IE_IRQ3
+ * 22 - VIA southbridge PIC IE_IRQ4
+ * 23 - unused IE_IRQ5
+ *
+ * The VIA chip is a master/slave 8259 setup and has the following interrupts:
+ *
+ * 8 - RTC
+ * 9 - PCI
+ * 14 - IDE0
+ * 15 - IDE1
+ */
+
+asmlinkage void cobalt_irq(struct pt_regs *regs)
+{
+ unsigned int pending = read_c0_status() & read_c0_cause();
+
+ if (pending & CAUSEF_IP2) { /* int 18 */
+ unsigned long irq_src = GALILEO_INL(GT_INTRCAUSE_OFS);
+
+ /* Check for timer irq ... */
+ if (irq_src & GALILEO_T0EXP) {
+ /* Clear the int line */
+ GALILEO_OUTL(0, GT_INTRCAUSE_OFS);
+ do_IRQ(COBALT_TIMER_IRQ, regs);
+ }
+ return;
+ }
+
+ if (pending & CAUSEF_IP6) { /* int 22 */
+ int irq = i8259_irq();
+
+ if (irq >= 0)
+ do_IRQ(irq, regs);
+ return;
+ }
+
+ if (pending & CAUSEF_IP3) { /* int 19 */
+ do_IRQ(COBALT_ETH0_IRQ, regs);
+ return;
+ }
+
+ if (pending & CAUSEF_IP4) { /* int 20 */
+ do_IRQ(COBALT_ETH1_IRQ, regs);
+ return;
+ }
+
+ if (pending & CAUSEF_IP5) { /* int 21 */
+ do_IRQ(COBALT_SERIAL_IRQ, regs);
+ return;
+ }
+
+ if (pending & CAUSEF_IP7) { /* int 23 */
+ do_IRQ(COBALT_QUBE_SLOT_IRQ, regs);
+ return;
+ }
+}
+
+void __init arch_init_irq(void)
+{
+ set_except_vector(0, cobalt_handle_int);
+
+ init_i8259_irqs(); /* 0 ... 15 */
+ mips_cpu_irq_init(16); /* 16 ... 23 */
+
+ /*
+ * Mask all cpu interrupts
+ * (except IE4, we already masked those at VIA level)
+ */
+ change_c0_status(ST0_IM, IE_IRQ4);
+}
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