feat(tc): allow TARGET_VERSION=4

Add basic support for TARGET_VERSION=4. It extends the existing 'if'
statements in the Makefile and the header to allow them to take the
value of 4 and also specifies the SCMI platform info to use for TC4.

Change-Id: I8d8257671314277a133e88ef65fae8fada93d00e
Signed-off-by: Jackson Cooper-Driver <jackson.cooper-driver@arm.com>
Signed-off-by: Leo Yan <leo.yan@arm.com>
diff --git a/plat/arm/board/tc/include/platform_def.h b/plat/arm/board/tc/include/platform_def.h
index 57bb55e..fb3d1f1 100644
--- a/plat/arm/board/tc/include/platform_def.h
+++ b/plat/arm/board/tc/include/platform_def.h
@@ -230,9 +230,9 @@
 
 #if TARGET_PLATFORM <= 2
 #define PLAT_ARM_DRAM2_BASE		ULL(0x8080000000)
-#elif TARGET_PLATFORM == 3
+#elif TARGET_PLATFORM >= 3
 #define PLAT_ARM_DRAM2_BASE		ULL(0x880000000)
-#endif /* TARGET_PLATFORM == 3 */
+#endif /* TARGET_PLATFORM >= 3 */
 #define PLAT_ARM_DRAM2_SIZE		ULL(0x180000000)
 #define PLAT_ARM_DRAM2_END		(PLAT_ARM_DRAM2_BASE + PLAT_ARM_DRAM2_SIZE - 1ULL)
 
@@ -294,9 +294,9 @@
 /* Message Handling Unit (MHU) base addresses */
 #if TARGET_PLATFORM <= 2
 	#define PLAT_CSS_MHU_BASE		UL(0x45400000)
-#elif TARGET_PLATFORM == 3
+#elif TARGET_PLATFORM >= 3
 	#define PLAT_CSS_MHU_BASE		UL(0x46000000)
-#endif /* TARGET_PLATFORM == 3 */
+#endif /* TARGET_PLATFORM >= 3 */
 #define PLAT_MHUV2_BASE			PLAT_CSS_MHU_BASE
 
 /* AP<->RSS MHUs */
diff --git a/plat/arm/board/tc/include/tc_helpers.S b/plat/arm/board/tc/include/tc_helpers.S
index 29130ea..9adf09a 100644
--- a/plat/arm/board/tc/include/tc_helpers.S
+++ b/plat/arm/board/tc/include/tc_helpers.S
@@ -81,6 +81,10 @@
 	ret
 endfunc TC_HANDLER(3)
 
+func TC_HANDLER(4)
+	ret
+endfunc TC_HANDLER(4)
+
 	/* -----------------------------------------------------
 	 * void plat_reset_handler(void);
 	 * -----------------------------------------------------