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>

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 1f254bd6c937..9a0ed364d4f7 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1289,6 +1289,18 @@ config HW_PERF_EVENTS
           Enable hardware performance counter support for perf events. If
           disabled, perf events will use software events only.
 
+config SPARSE_IRQ
+        bool "Support sparse irq numbering"
+        depends on EXPERIMENTAL
+        help
+          This enables support for sparse irqs. This is useful in general
+          as most CPUs have a fairly sparse array of IRQ vectors, which
+          the irq_desc then maps directly on to. Systems with a high
+          number of off-chip IRQs will want to treat this as
+          experimental until they have been independently verified.
+
+          If you don't know what to do here, say N.
+
 source "mm/Kconfig"
 
 config LEDS