Merge pull request #1335 from JoelHutton/jh/cleanup_void_pointers

Clean usage of void pointers to access symbols
diff --git a/bl1/bl1_private.h b/bl1/bl1_private.h
index 6ac3b8c..42a74d2 100644
--- a/bl1/bl1_private.h
+++ b/bl1/bl1_private.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -8,18 +8,16 @@
 #define __BL1_PRIVATE_H__
 
 #include <types.h>
+#include <utils_def.h>
 
 /*******************************************************************************
  * Declarations of linker defined symbols which will tell us where BL1 lives
  * in Trusted ROM and RAM
  ******************************************************************************/
-extern uintptr_t __BL1_ROM_END__;
-#define BL1_ROM_END (uintptr_t)(&__BL1_ROM_END__)
+IMPORT_SYM(uintptr_t, __BL1_ROM_END__,   BL1_ROM_END);
 
-extern uintptr_t __BL1_RAM_START__;
-extern uintptr_t __BL1_RAM_END__;
-#define BL1_RAM_BASE (uintptr_t)(&__BL1_RAM_START__)
-#define BL1_RAM_LIMIT (uintptr_t)(&__BL1_RAM_END__)
+IMPORT_SYM(uintptr_t, __BL1_RAM_START__, BL1_RAM_BASE);
+IMPORT_SYM(uintptr_t, __BL1_RAM_END__,   BL1_RAM_LIMIT);
 
 /******************************************
  * Function prototypes
diff --git a/common/runtime_svc.c b/common/runtime_svc.c
index 0ea4cd0..de80f30 100644
--- a/common/runtime_svc.c
+++ b/common/runtime_svc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -19,8 +19,6 @@
  * 'rt_svc_descs_indices' array. This gives the index of the descriptor in the
  * 'rt_svc_descs' array which contains the SMC handler.
  ******************************************************************************/
-#define RT_SVC_DESCS_START	((uintptr_t) (&__RT_SVC_DESCS_START__))
-#define RT_SVC_DESCS_END	((uintptr_t) (&__RT_SVC_DESCS_END__))
 uint8_t rt_svc_descs_indices[MAX_RT_SVCS];
 static rt_svc_desc_t *rt_svc_descs;
 
diff --git a/drivers/auth/img_parser_mod.c b/drivers/auth/img_parser_mod.c
index 6a01071..6316014 100644
--- a/drivers/auth/img_parser_mod.c
+++ b/drivers/auth/img_parser_mod.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -12,11 +12,10 @@
 #include <limits.h>
 #include <stdint.h>
 #include <string.h>
+#include <utils_def.h>
 
-extern uintptr_t __PARSER_LIB_DESCS_START__;
-extern uintptr_t __PARSER_LIB_DESCS_END__;
-#define PARSER_LIB_DESCS_START	((uintptr_t) (&__PARSER_LIB_DESCS_START__))
-#define PARSER_LIB_DESCS_END	((uintptr_t) (&__PARSER_LIB_DESCS_END__))
+IMPORT_SYM(uintptr_t, __PARSER_LIB_DESCS_START__,	PARSER_LIB_DESCS_START);
+IMPORT_SYM(uintptr_t, __PARSER_LIB_DESCS_END__,		PARSER_LIB_DESCS_END);
 static unsigned int parser_lib_indices[IMG_MAX_TYPES];
 static img_parser_lib_desc_t *parser_lib_descs;
 
diff --git a/include/common/bl_common.h b/include/common/bl_common.h
index 4ef916f..09a394d 100644
--- a/include/common/bl_common.h
+++ b/include/common/bl_common.h
@@ -64,33 +64,41 @@
 #include <types.h>
 #include <utils_def.h> /* To retain compatibility */
 
+
 /*
  * Declarations of linker defined symbols to help determine memory layout of
  * BL images
  */
 #if SEPARATE_CODE_AND_RODATA
-extern uintptr_t __TEXT_START__;
-extern uintptr_t __TEXT_END__;
-extern uintptr_t __RODATA_START__;
-extern uintptr_t __RODATA_END__;
+IMPORT_SYM(unsigned long, __TEXT_START__,	BL_CODE_BASE);
+IMPORT_SYM(unsigned long, __TEXT_END__,		BL_CODE_END);
+IMPORT_SYM(unsigned long, __RODATA_START__,	BL_RO_DATA_BASE);
+IMPORT_SYM(unsigned long, __RODATA_END__,	BL_RO_DATA_END);
 #else
-extern uintptr_t __RO_START__;
-extern uintptr_t __RO_END__;
+IMPORT_SYM(unsigned long, __RO_START__,		BL_CODE_BASE);
+IMPORT_SYM(unsigned long, __RO_END__,		BL_CODE_END);
 #endif
 
 #if defined(IMAGE_BL2)
-extern uintptr_t __BL2_END__;
+IMPORT_SYM(unsigned long, __BL2_END__,		BL2_END);
 #elif defined(IMAGE_BL2U)
-extern uintptr_t __BL2U_END__;
+IMPORT_SYM(unsigned long, __BL2U_END__,		BL2U_END);
 #elif defined(IMAGE_BL31)
-extern uintptr_t __BL31_END__;
+IMPORT_SYM(unsigned long, __BL31_END__,		BL31_END);
 #elif defined(IMAGE_BL32)
-extern uintptr_t __BL32_END__;
+IMPORT_SYM(unsigned long, __BL32_END__,		BL32_END);
 #endif /* IMAGE_BLX */
 
+/*
+ * The next 2 constants identify the extents of the coherent memory region.
+ * These addresses are used by the MMU setup code and therefore they must be
+ * page-aligned.  It is the responsibility of the linker script to ensure that
+ * __COHERENT_RAM_START__ and __COHERENT_RAM_END__ linker symbols refer to
+ * page-aligned addresses.
+ */
 #if USE_COHERENT_MEM
-extern uintptr_t __COHERENT_RAM_START__;
-extern uintptr_t __COHERENT_RAM_END__;
+IMPORT_SYM(unsigned long, __COHERENT_RAM_START__,	BL_COHERENT_RAM_BASE);
+IMPORT_SYM(unsigned long, __COHERENT_RAM_END__,		BL_COHERENT_RAM_END);
 #endif
 
 /*******************************************************************************
diff --git a/include/common/runtime_svc.h b/include/common/runtime_svc.h
index d12af22..5d9fa39 100644
--- a/include/common/runtime_svc.h
+++ b/include/common/runtime_svc.h
@@ -122,8 +122,8 @@
 void runtime_svc_init(void);
 uintptr_t handle_runtime_svc(uint32_t smc_fid, void *cookie, void *handle,
 						unsigned int flags);
-extern uintptr_t __RT_SVC_DESCS_START__;
-extern uintptr_t __RT_SVC_DESCS_END__;
+IMPORT_SYM(uintptr_t, __RT_SVC_DESCS_START__,		RT_SVC_DESCS_START);
+IMPORT_SYM(uintptr_t, __RT_SVC_DESCS_END__,		RT_SVC_DESCS_END);
 void init_crash_reporting(void);
 
 extern uint8_t rt_svc_descs_indices[MAX_RT_SVCS];
diff --git a/include/lib/utils_def.h b/include/lib/utils_def.h
index 4a5c3e0..8abc73c 100644
--- a/include/lib/utils_def.h
+++ b/include/lib/utils_def.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -99,4 +99,21 @@
 	((ARM_ARCH_MAJOR > _maj) || \
 	 ((ARM_ARCH_MAJOR == _maj) && (ARM_ARCH_MINOR >= _min)))
 
+/*
+ * Import an assembly or linker symbol as a C expression with the specified
+ * type
+ */
+#define IMPORT_SYM(type, sym, name) \
+	extern char sym[];\
+	static const __attribute__((unused)) type name = (type) sym;
+
+/*
+ * When the symbol is used to hold a pointer, its alignment can be asserted
+ * with this macro. For example, if there is a linker symbol that is going to
+ * be used as a 64-bit pointer, the value of the linker symbol must also be
+ * aligned to 64 bit. This macro makes sure this is the case.
+ */
+#define ASSERT_SYM_PTR_ALIGN(sym) assert(((size_t)(sym) % __alignof__(*(sym))) == 0)
+
+
 #endif /* __UTILS_DEF_H__ */
diff --git a/include/plat/common/common_def.h b/include/plat/common/common_def.h
index a841c3d..84923b9 100644
--- a/include/plat/common/common_def.h
+++ b/include/plat/common/common_def.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -74,33 +74,13 @@
  * page of it with the right memory attributes.
  */
 #if SEPARATE_CODE_AND_RODATA
-#define BL_CODE_BASE		(unsigned long)(&__TEXT_START__)
-#define BL_CODE_END		(unsigned long)(&__TEXT_END__)
-#define BL_RO_DATA_BASE		(unsigned long)(&__RODATA_START__)
-#define BL_RO_DATA_END		(unsigned long)(&__RODATA_END__)
 
 #define BL1_CODE_END		BL_CODE_END
-#define BL1_RO_DATA_BASE	(unsigned long)(&__RODATA_START__)
+#define BL1_RO_DATA_BASE	BL_RO_DATA_BASE
 #define BL1_RO_DATA_END		round_up(BL1_ROM_END, PAGE_SIZE)
 #else
-#define BL_CODE_BASE		(unsigned long)(&__RO_START__)
-#define BL_CODE_END		(unsigned long)(&__RO_END__)
 #define BL_RO_DATA_BASE		0
 #define BL_RO_DATA_END		0
-
 #define BL1_CODE_END		round_up(BL1_ROM_END, PAGE_SIZE)
-#define BL1_RO_DATA_BASE	0
-#define BL1_RO_DATA_END		0
 #endif /* SEPARATE_CODE_AND_RODATA */
-
-/*
- * The next 2 constants identify the extents of the coherent memory region.
- * These addresses are used by the MMU setup code and therefore they must be
- * page-aligned.  It is the responsibility of the linker script to ensure that
- * __COHERENT_RAM_START__ and __COHERENT_RAM_END__ linker symbols refer to
- * page-aligned addresses.
- */
-#define BL_COHERENT_RAM_BASE	(unsigned long)(&__COHERENT_RAM_START__)
-#define BL_COHERENT_RAM_END	(unsigned long)(&__COHERENT_RAM_END__)
-
 #endif /* __COMMON_DEF_H__ */
diff --git a/include/services/secure_partition.h b/include/services/secure_partition.h
index 93df2a1..f68f711 100644
--- a/include/services/secure_partition.h
+++ b/include/services/secure_partition.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -11,15 +11,11 @@
 #include <types.h>
 #include <utils_def.h>
 
-/* Linker symbols */
-extern uintptr_t __SP_IMAGE_XLAT_TABLES_START__;
-extern uintptr_t __SP_IMAGE_XLAT_TABLES_END__;
+/* Import linker symbols */
+IMPORT_SYM(uintptr_t, __SP_IMAGE_XLAT_TABLES_START__,	SP_IMAGE_XLAT_TABLES_START);
+IMPORT_SYM(uintptr_t, __SP_IMAGE_XLAT_TABLES_END__,	SP_IMAGE_XLAT_TABLES_END);
 
 /* Definitions */
-#define SP_IMAGE_XLAT_TABLES_START	\
-	(uintptr_t)(&__SP_IMAGE_XLAT_TABLES_START__)
-#define SP_IMAGE_XLAT_TABLES_END	\
-	(uintptr_t)(&__SP_IMAGE_XLAT_TABLES_END__)
 #define SP_IMAGE_XLAT_TABLES_SIZE	\
 	(SP_IMAGE_XLAT_TABLES_END - SP_IMAGE_XLAT_TABLES_START)
 
diff --git a/lib/locks/bakery/bakery_lock_normal.c b/lib/locks/bakery/bakery_lock_normal.c
index 8f59215..37697f5 100644
--- a/lib/locks/bakery/bakery_lock_normal.c
+++ b/lib/locks/bakery/bakery_lock_normal.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -10,6 +10,7 @@
 #include <cpu_data.h>
 #include <platform.h>
 #include <string.h>
+#include <utils_def.h>
 
 /*
  * Functions in this file implement Bakery Algorithm for mutual exclusion with the
@@ -49,8 +50,7 @@
  * Use the linker defined symbol which has evaluated the size reqiurement.
  * This is not as efficient as using a platform defined constant
  */
-extern void *__PERCPU_BAKERY_LOCK_SIZE__;
-#define PERCPU_BAKERY_LOCK_SIZE ((uintptr_t)&__PERCPU_BAKERY_LOCK_SIZE__)
+IMPORT_SYM(uintptr_t, __PERCPU_BAKERY_LOCK_SIZE__, PERCPU_BAKERY_LOCK_SIZE);
 #endif
 
 #define get_bakery_info(cpu_ix, lock)	\
diff --git a/lib/pmf/pmf_main.c b/lib/pmf/pmf_main.c
index 2cf260e..0208948 100644
--- a/lib/pmf/pmf_main.c
+++ b/lib/pmf/pmf_main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -11,6 +11,7 @@
 #include <platform.h>
 #include <pmf.h>
 #include <string.h>
+#include <utils_def.h>
 
 /*******************************************************************************
  * The 'pmf_svc_descs' array holds the PMF service descriptors exported by
@@ -21,16 +22,12 @@
  * index of the descriptor in the 'pmf_svc_descs' array  which contains the
  * service function pointers.
  ******************************************************************************/
-extern uintptr_t __PMF_SVC_DESCS_START__;
-extern uintptr_t __PMF_SVC_DESCS_END__;
-#define PMF_SVC_DESCS_START		((uintptr_t)(&__PMF_SVC_DESCS_START__))
-#define PMF_SVC_DESCS_END		((uintptr_t)(&__PMF_SVC_DESCS_END__))
-extern void *__PERCPU_TIMESTAMP_SIZE__;
-#define PMF_PERCPU_TIMESTAMP_SIZE	((uintptr_t)&__PERCPU_TIMESTAMP_SIZE__)
-extern uintptr_t __PMF_TIMESTAMP_START__;
-#define PMF_TIMESTAMP_ARRAY_START	((uintptr_t)&__PMF_TIMESTAMP_START__)
-extern uintptr_t __PMF_TIMESTAMP_END__;
-#define PMF_TIMESTAMP_ARRAY_END		((uintptr_t)&__PMF_TIMESTAMP_END__)
+
+IMPORT_SYM(uintptr_t, __PMF_SVC_DESCS_START__,		PMF_SVC_DESCS_START);
+IMPORT_SYM(uintptr_t, __PMF_SVC_DESCS_END__,		PMF_SVC_DESCS_END);
+IMPORT_SYM(uintptr_t, __PERCPU_TIMESTAMP_SIZE__,	PMF_PERCPU_TIMESTAMP_SIZE);
+IMPORT_SYM(intptr_t,  __PMF_TIMESTAMP_START__,		PMF_TIMESTAMP_ARRAY_START);
+IMPORT_SYM(uintptr_t, __PMF_TIMESTAMP_END__,		PMF_TIMESTAMP_ARRAY_END);
 
 #define PMF_SVC_DESCS_MAX		10
 
diff --git a/plat/hisilicon/hikey/hikey_bl1_setup.c b/plat/hisilicon/hikey/hikey_bl1_setup.c
index b19de05..28ad9df 100644
--- a/plat/hisilicon/hikey/hikey_bl1_setup.c
+++ b/plat/hisilicon/hikey/hikey_bl1_setup.c
@@ -23,23 +23,6 @@
 #include "../../bl1/bl1_private.h"
 #include "hikey_private.h"
 
-/*
- * Declarations of linker defined symbols which will help us find the layout
- * of trusted RAM
- */
-extern unsigned long __COHERENT_RAM_START__;
-extern unsigned long __COHERENT_RAM_END__;
-
-/*
- * The next 2 constants identify the extents of the coherent memory region.
- * These addresses are used by the MMU setup code and therefore they must be
- * page-aligned.  It is the responsibility of the linker script to ensure that
- * __COHERENT_RAM_START__ and __COHERENT_RAM_END__ linker symbols refer to
- * page-aligned addresses.
- */
-#define BL1_COHERENT_RAM_BASE (unsigned long)(&__COHERENT_RAM_START__)
-#define BL1_COHERENT_RAM_LIMIT (unsigned long)(&__COHERENT_RAM_END__)
-
 /* Data structure which holds the extents of the trusted RAM for BL1 */
 static meminfo_t bl1_tzram_layout;
 
@@ -103,8 +86,8 @@
 			   bl1_tzram_layout.total_size,
 			   BL1_RO_BASE,
 			   BL1_RO_LIMIT,
-			   BL1_COHERENT_RAM_BASE,
-			   BL1_COHERENT_RAM_LIMIT);
+			   BL_COHERENT_RAM_BASE,
+			   BL_COHERENT_RAM_END);
 }
 
 /*
diff --git a/plat/hisilicon/hikey960/hikey960_bl1_setup.c b/plat/hisilicon/hikey960/hikey960_bl1_setup.c
index 9cadba0..6a07f09 100644
--- a/plat/hisilicon/hikey960/hikey960_bl1_setup.c
+++ b/plat/hisilicon/hikey960/hikey960_bl1_setup.c
@@ -37,18 +37,6 @@
  * Declarations of linker defined symbols which will help us find the layout
  * of trusted RAM
  */
-extern unsigned long __COHERENT_RAM_START__;
-extern unsigned long __COHERENT_RAM_END__;
-
-/*
- * The next 2 constants identify the extents of the coherent memory region.
- * These addresses are used by the MMU setup code and therefore they must be
- * page-aligned.  It is the responsibility of the linker script to ensure that
- * __COHERENT_RAM_START__ and __COHERENT_RAM_END__ linker symbols refer to
- * page-aligned addresses.
- */
-#define BL1_COHERENT_RAM_BASE (unsigned long)(&__COHERENT_RAM_START__)
-#define BL1_COHERENT_RAM_LIMIT (unsigned long)(&__COHERENT_RAM_END__)
 
 /* Data structure which holds the extents of the trusted RAM for BL1 */
 static meminfo_t bl1_tzram_layout;
@@ -131,8 +119,8 @@
 			      bl1_tzram_layout.total_size,
 			      BL1_RO_BASE,
 			      BL1_RO_LIMIT,
-			      BL1_COHERENT_RAM_BASE,
-			      BL1_COHERENT_RAM_LIMIT);
+			      BL_COHERENT_RAM_BASE,
+			      BL_COHERENT_RAM_END);
 }
 
 static void hikey960_ufs_reset(void)
diff --git a/plat/hisilicon/poplar/bl1_plat_setup.c b/plat/hisilicon/poplar/bl1_plat_setup.c
index 3955113..25eed59 100644
--- a/plat/hisilicon/poplar/bl1_plat_setup.c
+++ b/plat/hisilicon/poplar/bl1_plat_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -23,13 +23,6 @@
 #include "hi3798cv200.h"
 #include "plat_private.h"
 
-/* Symbols from link script for conherent section */
-extern unsigned long __COHERENT_RAM_START__;
-extern unsigned long __COHERENT_RAM_END__;
-
-#define BL1_COHERENT_RAM_BASE	(unsigned long)(&__COHERENT_RAM_START__)
-#define BL1_COHERENT_RAM_LIMIT	(unsigned long)(&__COHERENT_RAM_END__)
-
 /* Data structure which holds the extents of the trusted RAM for BL1 */
 static meminfo_t bl1_tzram_layout;
 
@@ -92,8 +85,8 @@
 			       bl1_tzram_layout.total_size,
 			       BL1_RO_BASE, /* l-loader and BL1 ROM */
 			       BL1_RO_LIMIT,
-			       BL1_COHERENT_RAM_BASE,
-			       BL1_COHERENT_RAM_LIMIT);
+			       BL_COHERENT_RAM_BASE,
+			       BL_COHERENT_RAM_END);
 }
 
 void bl1_platform_setup(void)
diff --git a/plat/mediatek/mt6795/bl31_plat_setup.c b/plat/mediatek/mt6795/bl31_plat_setup.c
index 803f1ed..32f0157 100644
--- a/plat/mediatek/mt6795/bl31_plat_setup.c
+++ b/plat/mediatek/mt6795/bl31_plat_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -21,22 +21,21 @@
 #include <plat_private.h>
 #include <platform.h>
 #include <string.h>
+#include <utils_def.h>
 #include <xlat_tables.h>
+
 /*******************************************************************************
  * Declarations of linker defined symbols which will help us find the layout
  * of trusted SRAM
  ******************************************************************************/
-unsigned long __RO_START__;
-unsigned long __RO_END__;
-
 /*
  * The next 2 constants identify the extents of the code & RO data region.
  * These addresses are used by the MMU setup code and therefore they must be
  * page-aligned.  It is the responsibility of the linker script to ensure that
  * __RO_START__ and __RO_END__ linker symbols refer to page-aligned addresses.
  */
-#define BL31_RO_BASE (unsigned long)(&__RO_START__)
-#define BL31_RO_LIMIT (unsigned long)(&__RO_END__)
+IMPORT_SYM(unsigned long, __RO_START__,	BL31_RO_BASE);
+IMPORT_SYM(unsigned long, __RO_END__,	BL31_RO_LIMIT);
 
 /*
  * Placeholder variables for copying the arguments that have been passed to
diff --git a/plat/mediatek/mt8173/bl31_plat_setup.c b/plat/mediatek/mt8173/bl31_plat_setup.c
index 7b29307..e51bdbb 100644
--- a/plat/mediatek/mt8173/bl31_plat_setup.c
+++ b/plat/mediatek/mt8173/bl31_plat_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -17,24 +17,6 @@
 #include <platform.h>
 #include <spm.h>
 
-/*******************************************************************************
- * Declarations of linker defined symbols which will help us find the layout
- * of trusted SRAM
- ******************************************************************************/
-unsigned long __RO_START__;
-unsigned long __RO_END__;
-
-/*
- * The next 3 constants identify the extents of the code, RO data region and the
- * limit of the BL31 image.  These addresses are used by the MMU setup code and
- * therefore they must be page-aligned.  It is the responsibility of the linker
- * script to ensure that __RO_START__, __RO_END__ & __BL31_END__ linker symbols
- * refer to page-aligned addresses.
- */
-#define BL31_RO_BASE (unsigned long)(&__RO_START__)
-#define BL31_RO_LIMIT (unsigned long)(&__RO_END__)
-#define BL31_END (unsigned long)(&__BL31_END__)
-
 static entry_point_info_t bl32_ep_info;
 static entry_point_info_t bl33_ep_info;
 
@@ -156,10 +138,10 @@
 	plat_cci_init();
 	plat_cci_enable();
 
-	plat_configure_mmu_el3(BL31_RO_BASE,
-			       BL_COHERENT_RAM_END - BL31_RO_BASE,
-			       BL31_RO_BASE,
-			       BL31_RO_LIMIT,
+	plat_configure_mmu_el3(BL_CODE_BASE,
+			       BL_COHERENT_RAM_END - BL_CODE_BASE,
+			       BL_CODE_BASE,
+			       BL_CODE_END,
 			       BL_COHERENT_RAM_BASE,
 			       BL_COHERENT_RAM_END);
 }
diff --git a/plat/nvidia/tegra/common/tegra_bl31_setup.c b/plat/nvidia/tegra/common/tegra_bl31_setup.c
index d89ad7b..2fe4e7d 100644
--- a/plat/nvidia/tegra/common/tegra_bl31_setup.c
+++ b/plat/nvidia/tegra/common/tegra_bl31_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -23,6 +23,7 @@
 #include <string.h>
 #include <tegra_def.h>
 #include <tegra_private.h>
+#include <utils_def.h>
 
 /* length of Trusty's input parameters (in bytes) */
 #define TRUSTY_PARAMS_LEN_BYTES	(4096*2)
@@ -33,29 +34,17 @@
  * Declarations of linker defined symbols which will help us find the layout
  * of trusted SRAM
  ******************************************************************************/
-extern unsigned long __TEXT_START__;
-extern unsigned long __TEXT_END__;
-extern unsigned long __RW_START__;
-extern unsigned long __RW_END__;
-extern unsigned long __RODATA_START__;
-extern unsigned long __RODATA_END__;
-extern unsigned long __BL31_END__;
+
+IMPORT_SYM(unsigned long, __RW_START__,		BL31_RW_START);
+IMPORT_SYM(unsigned long, __RW_END__,		BL31_RW_END);
+IMPORT_SYM(unsigned long, __RODATA_START__,	BL31_RODATA_BASE);
+IMPORT_SYM(unsigned long, __RODATA_END__,	BL31_RODATA_END);
+IMPORT_SYM(unsigned long, __TEXT_START__,	TEXT_START);
+IMPORT_SYM(unsigned long, __TEXT_END__,		TEXT_END);
 
 extern uint64_t tegra_bl31_phys_base;
 extern uint64_t tegra_console_base;
 
-/*
- * The next 3 constants identify the extents of the code, RO data region and the
- * limit of the BL3-1 image.  These addresses are used by the MMU setup code and
- * therefore they must be page-aligned.  It is the responsibility of the linker
- * script to ensure that __RO_START__, __RO_END__ & __BL31_END__ linker symbols
- * refer to page-aligned addresses.
- */
-#define BL31_RW_START (unsigned long)(&__RW_START__)
-#define BL31_RW_END (unsigned long)(&__RW_END__)
-#define BL31_RODATA_BASE (unsigned long)(&__RODATA_START__)
-#define BL31_RODATA_END (unsigned long)(&__RODATA_END__)
-#define BL31_END (unsigned long)(&__BL31_END__)
 
 static entry_point_info_t bl33_image_ep_info, bl32_image_ep_info;
 static plat_params_from_bl2_t plat_bl31_params_from_bl2 = {
@@ -311,8 +300,8 @@
 	unsigned long rw_size = BL31_RW_END - BL31_RW_START;
 	unsigned long rodata_start = BL31_RODATA_BASE;
 	unsigned long rodata_size = BL31_RODATA_END - BL31_RODATA_BASE;
-	unsigned long code_base = (unsigned long)(&__TEXT_START__);
-	unsigned long code_size = (unsigned long)(&__TEXT_END__) - code_base;
+	unsigned long code_base = TEXT_START;
+	unsigned long code_size = TEXT_END - TEXT_START;
 	const mmap_region_t *plat_mmio_map = NULL;
 #if USE_COHERENT_MEM
 	unsigned long coh_start, coh_size;
diff --git a/plat/rockchip/common/bl31_plat_setup.c b/plat/rockchip/common/bl31_plat_setup.c
index 6199eda..e5ee68f 100644
--- a/plat/rockchip/common/bl31_plat_setup.c
+++ b/plat/rockchip/common/bl31_plat_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -17,21 +17,14 @@
 #include <platform_def.h>
 #include <uart_16550.h>
 
-/*******************************************************************************
- * Declarations of linker defined symbols which will help us find the layout
- * of trusted SRAM
- ******************************************************************************/
-unsigned long __RO_START__;
-unsigned long __RO_END__;
-
 /*
  * The next 2 constants identify the extents of the code & RO data region.
  * These addresses are used by the MMU setup code and therefore they must be
  * page-aligned.  It is the responsibility of the linker script to ensure that
  * __RO_START__ and __RO_END__ linker symbols refer to page-aligned addresses.
  */
-#define BL31_RO_BASE (unsigned long)(&__RO_START__)
-#define BL31_RO_LIMIT (unsigned long)(&__RO_END__)
+IMPORT_SYM(unsigned long, __RO_START__,	BL31_RO_BASE);
+IMPORT_SYM(unsigned long, __RO_END__,	BL31_RO_LIMIT);
 
 static entry_point_info_t bl32_ep_info;
 static entry_point_info_t bl33_ep_info;
diff --git a/services/std_svc/spm/spm_shim_private.h b/services/std_svc/spm/spm_shim_private.h
index ad953cd..8408d1e 100644
--- a/services/std_svc/spm/spm_shim_private.h
+++ b/services/std_svc/spm/spm_shim_private.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -8,21 +8,17 @@
 #define __SPM_SHIM_PRIVATE__
 
 #include <types.h>
+#include <utils_def.h>
 
 /* Assembly source */
-extern uintptr_t spm_shim_exceptions_ptr;
+IMPORT_SYM(uintptr_t, spm_shim_exceptions_ptr,		SPM_SHIM_EXCEPTIONS_PTR);
 
 /* Linker symbols */
-extern uintptr_t __SPM_SHIM_EXCEPTIONS_START__;
-extern uintptr_t __SPM_SHIM_EXCEPTIONS_END__;
+IMPORT_SYM(uintptr_t, __SPM_SHIM_EXCEPTIONS_START__,	SPM_SHIM_EXCEPTIONS_START);
+IMPORT_SYM(uintptr_t, __SPM_SHIM_EXCEPTIONS_END__,	SPM_SHIM_EXCEPTIONS_END);
 
 /* Definitions */
-#define SPM_SHIM_EXCEPTIONS_PTR		(uintptr_t)(&spm_shim_exceptions_ptr)
 
-#define SPM_SHIM_EXCEPTIONS_START	\
-	(uintptr_t)(&__SPM_SHIM_EXCEPTIONS_START__)
-#define SPM_SHIM_EXCEPTIONS_END		\
-	(uintptr_t)(&__SPM_SHIM_EXCEPTIONS_END__)
 #define SPM_SHIM_EXCEPTIONS_SIZE	\
 	(SPM_SHIM_EXCEPTIONS_END - SPM_SHIM_EXCEPTIONS_START)