powerpc: Enable sparse irq_descs on powerpc
Defining CONFIG_SPARSE_IRQ enables generic code that gets rid of the
static irq_desc array, and replaces it with an array of pointers to
irq_descs.
It also allows node local allocation of irq_descs, however we
currently don't have the information available to do that, so we just
allocate them on all on node 0.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
index 03dc28cd..c85a32f 100644
--- a/arch/powerpc/include/asm/irq.h
+++ b/arch/powerpc/include/asm/irq.h
@@ -38,6 +38,9 @@
/* Number of irqs reserved for the legacy controller */
#define NUM_ISA_INTERRUPTS 16
+/* Same thing, used by the generic IRQ code */
+#define NR_IRQS_LEGACY NUM_ISA_INTERRUPTS
+
/* This type is the placeholder for a hardware interrupt number. It has to
* be big enough to enclose whatever representation is used by a given
* platform.