ARM: gic: allow GIC to support non-banked setups

The GIC support code is heavily using the fact that hardware
implementations are exposing banked registers. Unfortunately, it
looks like at least one GIC implementation (EXYNOS) offers both
the distributor and the CPU interfaces at different addresses,
depending on the CPU.

This problem is solved by allowing the distributor and CPU interface
addresses to be per-cpu variables for the platforms that require it.
The EXYNOS code is updated not to mess with the GIC internals while
handling interrupts, and struct gic_chip_data is back to being private.
The DT binding for the gic is updated to allow an optional "cpu-offset"
value, which is used to compute the various base addresses.

Finally, a new config option (GIC_NON_BANKED) is used to control this
feature, so the overhead is only present on kernels compiled with
support for EXYNOS.

Tested on Origen (EXYNOS4) and Panda (OMAP4).

Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/arm/plat-s5p/Kconfig b/arch/arm/plat-s5p/Kconfig
index 9b9968fa8695..8167ce66188c 100644
--- a/arch/arm/plat-s5p/Kconfig
+++ b/arch/arm/plat-s5p/Kconfig
@@ -11,6 +11,7 @@ config PLAT_S5P
 	default y
 	select ARM_VIC if !ARCH_EXYNOS4
 	select ARM_GIC if ARCH_EXYNOS4
+	select GIC_NON_BANKED if ARCH_EXYNOS4
 	select NO_IOPORT
 	select ARCH_REQUIRE_GPIOLIB
 	select S3C_GPIO_TRACK