ARM: 6197/2: preliminary support for sparse IRQ

So to allow NR_IRQS to be dynamic and platforms to specify the number
of IRQs really needed.

Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h
index 237282f..2721a58 100644
--- a/arch/arm/include/asm/irq.h
+++ b/arch/arm/include/asm/irq.h
@@ -7,6 +7,8 @@
 #define irq_canonicalize(i)	(i)
 #endif
 
+#define NR_IRQS_LEGACY	16
+
 /*
  * Use this value to indicate lack of interrupt
  * capability
diff --git a/arch/arm/include/asm/mach/arch.h b/arch/arm/include/asm/mach/arch.h
index c59842d..5ee6f85 100644
--- a/arch/arm/include/asm/mach/arch.h
+++ b/arch/arm/include/asm/mach/arch.h
@@ -20,6 +20,7 @@
 	 * by assembler code in head.S, head-common.S
 	 */
 	unsigned int		nr;		/* architecture number	*/
+	unsigned int		nr_irqs;	/* number of IRQs */
 	unsigned int		phys_io;	/* start of physical io	*/
 	unsigned int		io_pg_offst;	/* byte offset for io 
 						 * page tabe entry	*/
diff --git a/arch/arm/include/asm/mach/irq.h b/arch/arm/include/asm/mach/irq.h
index 8920b2d6..ce3eee9f 100644
--- a/arch/arm/include/asm/mach/irq.h
+++ b/arch/arm/include/asm/mach/irq.h
@@ -17,6 +17,7 @@
 /*
  * This is internal.  Do not use it.
  */
+extern unsigned int arch_nr_irqs;
 extern void (*init_arch_irq)(void);
 extern void init_FIQ(void);
 extern int show_fiq_list(struct seq_file *, void *);