-extern void disable_irq(unsigned int);
-extern void disable_irq_nosync(unsigned int);
-extern void enable_irq(unsigned int);
+#ifdef CONFIG_MIPS_MT_SMTC
+/*
+ * Clear interrupt mask handling "backstop" if irq_hwmask
+ * entry so indicates. This implies that the ack() or end()
+ * functions will take over re-enabling the low-level mask.
+ * Otherwise it will be done on return from exception.
+ */
+#define __DO_IRQ_SMTC_HOOK(irq) \
+do { \
+ if (irq_hwmask[irq] & 0x0000ff00) \
+ write_c0_tccontext(read_c0_tccontext() & \
+ ~(irq_hwmask[irq] & 0x0000ff00)); \
+} while (0)
+#else
+#define __DO_IRQ_SMTC_HOOK(irq) do { } while (0)
+#endif