ARM: rpc: make default fiq handler run-time installed

Only rpc uses disable_fiq macro. Change it to a run-time installed
default FIQ handler. The handler is installed before FIQ is enabled
so the behavior should be unchanged.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nico@linaro.org>

arch/arm/mach-rpc/Makefile

@@ -4,7 +4,7 @@
 
 # Object file lists.
 
-obj-y			:= dma.o irq.o riscpc.o
+obj-y			:= dma.o fiq.o irq.o riscpc.o
 obj-m			:=
 obj-n			:=
 obj-			:=

arch/arm/mach-rpc/fiq.S

+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <mach/hardware.h>
+#include <mach/entry-macro.S>
+
+	.text
+
+	.global	rpc_default_fiq_end
+ENTRY(rpc_default_fiq_start)
+	mov	r12, #ioc_base_high
+	.if	ioc_base_low
+	orr	r12, r12, #ioc_base_low
+	.endif
+	strb	r12, [r12, #0x38]	@ Disable FIQ register
+	subs	pc, lr, #4
+rpc_default_fiq_end:

arch/arm/mach-rpc/irq.c

@@ -5,6 +5,7 @@
 #include <asm/mach/irq.h>
 #include <asm/hardware/iomd.h>
 #include <asm/irq.h>
+#include <asm/fiq.h>
 
 static void iomd_ack_irq_a(struct irq_data *d)
 {
@@ -112,6 +113,8 @@ static struct irq_chip iomd_fiq_chip = {
 	.irq_unmask	= iomd_unmask_irq_fiq,
 };
 
+extern unsigned char rpc_default_fiq_start, rpc_default_fiq_end;
+
 void __init rpc_init_irq(void)
 {
 	unsigned int irq, flags;
@@ -121,6 +124,9 @@ void __init rpc_init_irq(void)
 	iomd_writeb(0, IOMD_FIQMASK);
 	iomd_writeb(0, IOMD_DMAMASK);
 
+	set_fiq_handler(&rpc_default_fiq_start,
+		&rpc_default_fiq_end - &rpc_default_fiq_start);
+
 	for (irq = 0; irq < NR_IRQS; irq++) {
 		flags = IRQF_VALID;