Add API to return memory map on ARM platforms

Functions to configure the MMU in S-EL1 and EL3 on ARM platforms
expect each platform to export its memory map in the `plat_arm_mmap`
data structure. This approach does not scale well in case the memory
map cannot be determined until runtime. To cater for this possibility,
this patch introduces the plat_arm_get_mmap() API. It returns a
reference to the `plat_arm_mmap` by default but can be overridden
by a platform if required.

Change-Id: Idae6ad8fdf40cdddcd8b992abc188455fa047c74

include/plat/arm/common/plat_arm.h

 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -37,11 +37,6 @@
 #include <stdint.h>
 #include <xlat_tables.h>
 
-/*
- * Extern declarations common to ARM standard platforms
- */
-extern const mmap_region_t plat_arm_mmap[];
-
 #define ARM_CASSERT_MMAP						\
 	CASSERT((ARRAY_SIZE(plat_arm_mmap) + ARM_BL_REGIONS)		\
 		<= MAX_MMAP_REGIONS,					\
@@ -204,6 +199,6 @@ int plat_arm_get_alt_image_source(
 	uintptr_t *dev_handle,
 	uintptr_t *image_spec);
 unsigned int plat_arm_calc_core_pos(u_register_t mpidr);
-
+const mmap_region_t *plat_arm_get_mmap(void);
 
 #endif /* __PLAT_ARM_H__ */

plat/arm/common/aarch64/arm_common.c

 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -35,6 +35,7 @@
 #include <platform_def.h>
 #include <xlat_tables.h>
 
+extern const mmap_region_t plat_arm_mmap[];
 
 static const int cci_map[] = {
 	PLAT_ARM_CCI_CLUSTER0_SL_IFACE_IX,
@@ -43,6 +44,7 @@ static const int cci_map[] = {
 
 /* Weak definitions may be overridden in specific ARM standard platform */
 #pragma weak plat_get_ns_image_entrypoint
+#pragma weak plat_arm_get_mmap
 
 
 /*******************************************************************************
@@ -67,7 +69,7 @@ static const int cci_map[] = {
 		mmap_add_region(coh_start, coh_start,			\
 				coh_limit - coh_start,			\
 				MT_DEVICE | MT_RW | MT_SECURE);		\
-		mmap_add(plat_arm_mmap);				\
+		mmap_add(plat_arm_get_mmap());				\
 		init_xlat_tables();					\
 									\
 		enable_mmu_el##_el(0);					\
@@ -85,7 +87,7 @@ static const int cci_map[] = {
 		mmap_add_region(ro_start, ro_start,			\
 				ro_limit - ro_start,			\
 				MT_MEMORY | MT_RO | MT_SECURE);		\
-		mmap_add(plat_arm_mmap);				\
+		mmap_add(plat_arm_get_mmap());				\
 		init_xlat_tables();					\
 									\
 		enable_mmu_el##_el(0);					\
@@ -161,3 +163,11 @@ void arm_configure_sys_timer(void)
 	reg_val = (1 << CNTNSAR_NS_SHIFT(PLAT_ARM_NSTIMER_FRAME_ID));
 	mmio_write_32(ARM_SYS_TIMCTL_BASE + CNTNSAR, reg_val);
 }
+
+/*******************************************************************************
+ * Returns ARM platform specific memory map regions.
+ ******************************************************************************/
+const mmap_region_t *plat_arm_get_mmap(void)
+{
+	return plat_arm_mmap;
+}