gic multichip: add support for clayton

GIC-Clayton supports multichip operation mode which allows it to connect
upto 16 other GIC-Clayton instances. GIC-Clayton's multichip programming
and operation remains same as GIC-600 with a minor change in the
SPI_BLOCKS and SPI_BLOCK_MIN shifts to accommodate additional SPI
ranges. So identify if the GIC v4 extension is enabled by the platform
makefile and appropriately select the SPI_BLOCKS and SPI_BLOCK_MIN
shifts.

Change-Id: I95fd80ef16af6c7ca09e2335539187b133052d41
Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>

drivers/arm/gic/v3/gic600_multichip_private.h

@@ -24,11 +24,21 @@
 
 /* GIC600 GICD multichip related shifts */
 #define GICD_CHIPRx_ADDR_SHIFT		16
-#define GICD_CHIPRx_SPI_BLOCK_MIN_SHIFT	10
-#define GICD_CHIPRx_SPI_BLOCKS_SHIFT	5
 #define GICD_CHIPSR_RTS_SHIFT		4
 #define GICD_DCHIPR_RT_OWNER_SHIFT	4
 
+/*
+ * If GIC v4 extension is enabled, then use SPI macros specific to GIC-Clayton.
+ * Other shifts and mask remains same between GIC-600 and GIC-Clayton.
+ */
+#if GIC_ENABLE_V4_EXTN
+#define GICD_CHIPRx_SPI_BLOCK_MIN_SHIFT	9
+#define GICD_CHIPRx_SPI_BLOCKS_SHIFT	3
+#else
+#define GICD_CHIPRx_SPI_BLOCK_MIN_SHIFT	10
+#define GICD_CHIPRx_SPI_BLOCKS_SHIFT	5
+#endif
+
 #define GICD_CHIPSR_RTS_STATE_DISCONNECTED	U(0)
 #define GICD_CHIPSR_RTS_STATE_UPDATING		U(1)
 #define GICD_CHIPSR_RTS_STATE_CONSISTENT	U(2)