+static inline int clz(unsigned long x)
+{
+ __asm__ (
+ " .set push \n"
+ " .set mips32 \n"
+ " clz %0, %1 \n"
+ " .set pop \n"
+ : "=r" (x)
+ : "r" (x));
+
+ return x;
+}
+
+/*
+ * Version of ffs that only looks at bits 12..15.
+ */
+static inline unsigned int irq_ffs(unsigned int pending)
+{
+#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
+ return -clz(pending) + 31 - CAUSEB_IP;
+#else
+ unsigned int a0 = 7;
+ unsigned int t0;
+
+ t0 = pending & 0xf000;
+ t0 = t0 < 1;
+ t0 = t0 << 2;
+ a0 = a0 - t0;
+ pending = pending << t0;
+
+ t0 = pending & 0xc000;
+ t0 = t0 < 1;
+ t0 = t0 << 1;
+ a0 = a0 - t0;
+ pending = pending << t0;
+
+ t0 = pending & 0x8000;
+ t0 = t0 < 1;
+ //t0 = t0 << 2;
+ a0 = a0 - t0;
+ //pending = pending << t0;
+
+ return a0;
+#endif
+}
+
+/*
+ * IRQs on the Malta board look basically (barring software IRQs which we
+ * don't use at all and all external interrupt sources are combined together
+ * on hardware interrupt 0 (MIPS IRQ 2)) like:
+ *
+ * MIPS IRQ Source
+ * -------- ------
+ * 0 Software (ignored)
+ * 1 Software (ignored)
+ * 2 Combined hardware interrupt (hw0)
+ * 3 Hardware (ignored)
+ * 4 Hardware (ignored)
+ * 5 Hardware (ignored)
+ * 6 Hardware (ignored)
+ * 7 R4k timer (what we use)
+ *
+ * We handle the IRQ according to _our_ priority which is:
+ *
+ * Highest ---- R4k Timer
+ * Lowest ---- Combined hardware interrupt
+ *
+ * then we just return, if multiple IRQs are pending then we will just take
+ * another exception, big deal.
+ */
+
+asmlinkage void plat_irq_dispatch(void)
+{
+ unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
+ int irq;
+
+ irq = irq_ffs(pending);
+
+ if (irq == MIPSCPU_INT_I8259A)
+ malta_hw0_irqdispatch();
+ else if (irq > 0)
+ do_IRQ(MIPSCPU_INT_BASE + irq);
+ else
+ spurious_interrupt();
+}
+
+static struct irqaction i8259irq = {
+ .handler = no_action,
+ .name = "XT-PIC cascade"
+};
+
+static struct irqaction corehi_irqaction = {
+ .handler = no_action,
+ .name = "CoreHi"
+};
+
+msc_irqmap_t __initdata msc_irqmap[] = {
+ {MSC01C_INT_TMR, MSC01_IRQ_EDGE, 0},
+ {MSC01C_INT_PCI, MSC01_IRQ_LEVEL, 0},
+};
+int __initdata msc_nr_irqs = sizeof(msc_irqmap)/sizeof(msc_irqmap_t);
+
+msc_irqmap_t __initdata msc_eicirqmap[] = {
+ {MSC01E_INT_SW0, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_SW1, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_I8259A, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_SMI, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_COREHI, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_CORELO, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_TMR, MSC01_IRQ_EDGE, 0},
+ {MSC01E_INT_PCI, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_PERFCTR, MSC01_IRQ_LEVEL, 0},
+ {MSC01E_INT_CPUCTR, MSC01_IRQ_LEVEL, 0}
+};
+int __initdata msc_nr_eicirqs = sizeof(msc_eicirqmap)/sizeof(msc_irqmap_t);
+