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-rw-r--r--include/asm-arm/arch-shark/irq.h123
1 files changed, 123 insertions, 0 deletions
diff --git a/include/asm-arm/arch-shark/irq.h b/include/asm-arm/arch-shark/irq.h
new file mode 100644
index 000000000..7dae77e02
--- /dev/null
+++ b/include/asm-arm/arch-shark/irq.h
@@ -0,0 +1,123 @@
+/*
+ * linux/include/asm-arm/arch-shark/irq.h
+ *
+ * by Alexander.Schulz@stud.uni-karlsruhe.de
+ *
+ * derived from linux/arch/ppc/kernel/i8259.c and:
+ * include/asm-arm/arch-ebsa110/irq.h
+ * Copyright (C) 1996-1998 Russell King
+ */
+
+#define fixup_irq(x) (x)
+
+/*
+ * 8259A PIC functions to handle ISA devices:
+ */
+
+/*
+ * This contains the irq mask for both 8259A irq controllers,
+ * Let through the cascade-interrupt no. 2 (ff-(1<<2)==fb)
+ */
+static unsigned char cached_irq_mask[2] = { 0xfb, 0xff };
+
+/*
+ * These have to be protected by the irq controller spinlock
+ * before being called.
+ */
+static void shark_disable_8259A_irq(unsigned int irq)
+{
+ unsigned int mask;
+ if (irq<8) {
+ mask = 1 << irq;
+ cached_irq_mask[0] |= mask;
+ } else {
+ mask = 1 << (irq-8);
+ cached_irq_mask[1] |= mask;
+ }
+ outb(cached_irq_mask[1],0xA1);
+ outb(cached_irq_mask[0],0x21);
+}
+
+static void shark_enable_8259A_irq(unsigned int irq)
+{
+ unsigned int mask;
+ if (irq<8) {
+ mask = ~(1 << irq);
+ cached_irq_mask[0] &= mask;
+ } else {
+ mask = ~(1 << (irq-8));
+ cached_irq_mask[1] &= mask;
+ }
+ outb(cached_irq_mask[1],0xA1);
+ outb(cached_irq_mask[0],0x21);
+}
+
+/*
+ * Careful! The 8259A is a fragile beast, it pretty
+ * much _has_ to be done exactly like this (mask it
+ * first, _then_ send the EOI, and the order of EOI
+ * to the two 8259s is important!
+ */
+static void shark_mask_and_ack_8259A_irq(unsigned int irq)
+{
+ if (irq & 8) {
+ cached_irq_mask[1] |= 1 << (irq-8);
+ inb(0xA1); /* DUMMY */
+ outb(cached_irq_mask[1],0xA1);
+ } else {
+ cached_irq_mask[0] |= 1 << irq;
+ outb(cached_irq_mask[0],0x21);
+ }
+}
+
+static void bogus_int(int irq, void *dev_id, struct pt_regs *regs)
+{
+ printk("Got interrupt %i!\n",irq);
+}
+
+static struct irqaction cascade;
+
+static __inline__ void irq_init_irq(void)
+{
+ int irq;
+
+ for (irq = 0; irq < NR_IRQS; irq++) {
+ irq_desc[irq].valid = 1;
+ irq_desc[irq].probe_ok = 1;
+ irq_desc[irq].mask_ack = shark_mask_and_ack_8259A_irq;
+ irq_desc[irq].mask = shark_disable_8259A_irq;
+ irq_desc[irq].unmask = shark_enable_8259A_irq;
+ }
+
+ /* The PICs are initialized to level triggered and auto eoi!
+ * If they are set to edge triggered they lose some IRQs,
+ * if they are set to manual eoi they get locked up after
+ * a short time
+ */
+
+ /* init master interrupt controller */
+ outb(0x19, 0x20); /* Start init sequence, level triggered */
+ outb(0x00, 0x21); /* Vector base */
+ outb(0x04, 0x21); /* Cascade (slave) on IRQ2 */
+ outb(0x03, 0x21); /* Select 8086 mode , auto eoi*/
+ outb(0x0A, 0x20);
+ /* init slave interrupt controller */
+ outb(0x19, 0xA0); /* Start init sequence, level triggered */
+ outb(0x08, 0xA1); /* Vector base */
+ outb(0x02, 0xA1); /* Cascade (slave) on IRQ2 */
+ outb(0x03, 0xA1); /* Select 8086 mode, auto eoi */
+ outb(0x0A, 0xA0);
+ outb(cached_irq_mask[1],0xA1);
+ outb(cached_irq_mask[0],0x21);
+ //request_region(0x20,0x2,"pic1");
+ //request_region(0xA0,0x2,"pic2");
+
+ cascade.handler = bogus_int;
+ cascade.flags = 0;
+ cascade.mask = 0;
+ cascade.name = "cascade";
+ cascade.next = NULL;
+ cascade.dev_id = NULL;
+ setup_arm_irq(2,&cascade);
+
+}