diff --git a/software/include/base/irq.h b/software/include/base/irq.h
index 37cf73fd0..33bd05beb 100644
--- a/software/include/base/irq.h
+++ b/software/include/base/irq.h
@@ -49,9 +49,4 @@ static inline unsigned int irq_pending(void)
        return pending;
 }
 
-static inline void irq_ack(unsigned int mask)
-{
-       __asm__ __volatile__("wcsr IP, %0" : : "r" (mask));
-}
-
 #endif /* __IRQ_H */
diff --git a/software/libbase/system.c b/software/libbase/system.c
index 0edcb8180..b253c2142 100644
--- a/software/libbase/system.c
+++ b/software/libbase/system.c
@@ -44,7 +44,7 @@ __attribute__((noreturn)) void reboot(void)
 {
 	uart_sync();
 	irq_setmask(0);
-	irq_enable(0);
+	irq_setie(0);
 	CSR_SYSTEM_ID = 1; /* Writing to CSR_SYSTEM_ID causes a system reset */
 	while(1);
 }
@@ -61,7 +61,7 @@ __attribute__((noreturn)) void reconf(void)
 {
 	uart_sync();
 	irq_setmask(0);
-	irq_enable(0);
+	irq_setie(0);
 	icap_write(0, 0xffff); /* dummy word */
 	icap_write(0, 0xffff); /* dummy word */
 	icap_write(0, 0xffff); /* dummy word */
diff --git a/software/libbase/uart.c b/software/libbase/uart.c
index 8490bcdf8..248e5f527 100644
--- a/software/libbase/uart.c
+++ b/software/libbase/uart.c
@@ -62,7 +62,6 @@ void uart_isr(void)
 	}
 
 	CSR_UART_EV_PENDING = stat;
-	irq_ack(IRQ_UART);
 }
 
 /* Do not use in interrupt handlers! */
@@ -108,8 +107,6 @@ void uart_init(void)
 	tx_consume = 0;
 	tx_cts = 1;
 
-	irq_ack(IRQ_UART);
-
 	/* ack any events */
 	CSR_UART_EV_PENDING = CSR_UART_EV_PENDING;