linker_script: move .data section to bl_common.ld.h

Move the data section to the common header.

I slightly tweaked some scripts as follows:

[1] bl1.ld.S has ALIGN(16). I added DATA_ALIGN macro, which is 1
    by default, but overridden by bl1.ld.S. Currently, ALIGN(16)
    of the .data section is redundant because commit 412865907699
    ("Fix boot failures on some builds linked with ld.lld.") padded
    out the previous section to work around the issue of LLD version
    <= 10.0. This will be fixed in the future release of LLVM, so
    I am keeping the proper way to align LMA.

[2] bl1.ld.S and bl2_el3.ld.S define __DATA_RAM_{START,END}__ instead
    of __DATA_{START,END}__. I put them out of the .data section.

[3] SORT_BY_ALIGNMENT() is missing tsp.ld.S, sp_min.ld.S, and
    mediatek/mt6795/bl31.ld.S. This commit adds SORT_BY_ALIGNMENT()
    for all images, so the symbol order in those three will change,
    but I do not think it is a big deal.

Change-Id: I215bb23c319f045cd88e6f4e8ee2518c67f03692
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/bl1/bl1.ld.S b/bl1/bl1.ld.S
index 4ebe8a0..bc23828 100644
--- a/bl1/bl1.ld.S
+++ b/bl1/bl1.ld.S
@@ -4,6 +4,14 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
+/*
+ * The .data section gets copied from ROM to RAM at runtime.
+ * Its LMA should be 16-byte aligned to allow efficient copying of 16-bytes
+ * aligned regions in it.
+ * Its VMA must be page-aligned as it marks the first read/write page.
+ */
+#define DATA_ALIGN	16
+
 #include <common/bl_common.ld.h>
 #include <lib/xlat_tables/xlat_tables_defs.h>
 
@@ -87,21 +95,9 @@
     ASSERT(BL1_RW_BASE == ALIGN(PAGE_SIZE),
            "BL1_RW_BASE address is not aligned on a page boundary.")
 
-    /*
-     * The .data section gets copied from ROM to RAM at runtime.
-     * Its LMA should be 16-byte aligned to allow efficient copying of 16-bytes
-     * aligned regions in it.
-     * Its VMA must be page-aligned as it marks the first read/write page.
-     *
-     * It must be placed at a lower address than the stacks if the stack
-     * protector is enabled. Alternatively, the .data.stack_protector_canary
-     * section can be placed independently of the main .data section.
-     */
-    .data . : ALIGN(16) {
-        __DATA_RAM_START__ = .;
-        *(SORT_BY_ALIGNMENT(.data*))
-        __DATA_RAM_END__ = .;
-    } >RAM AT>ROM
+    DATA_SECTION >RAM AT>ROM
+    __DATA_RAM_START__ = __DATA_START__;
+    __DATA_RAM_END__ = __DATA_END__;
 
     STACK_SECTION >RAM
     BSS_SECTION >RAM
diff --git a/bl2/bl2.ld.S b/bl2/bl2.ld.S
index 17475f0..37849c3 100644
--- a/bl2/bl2.ld.S
+++ b/bl2/bl2.ld.S
@@ -77,17 +77,7 @@
      */
     __RW_START__ = . ;
 
-    /*
-     * .data must be placed at a lower address than the stacks if the stack
-     * protector is enabled. Alternatively, the .data.stack_protector_canary
-     * section can be placed independently of the main .data section.
-     */
-    .data . : {
-        __DATA_START__ = .;
-        *(SORT_BY_ALIGNMENT(.data*))
-        __DATA_END__ = .;
-    } >RAM
-
+    DATA_SECTION >RAM
     STACK_SECTION >RAM
     BSS_SECTION >RAM
     XLAT_TABLE_SECTION >RAM
diff --git a/bl2/bl2_el3.ld.S b/bl2/bl2_el3.ld.S
index ea7a235..8c45d98 100644
--- a/bl2/bl2_el3.ld.S
+++ b/bl2/bl2_el3.ld.S
@@ -101,16 +101,9 @@
      */
     __RW_START__ = . ;
 
-    /*
-     * .data must be placed at a lower address than the stacks if the stack
-     * protector is enabled. Alternatively, the .data.stack_protector_canary
-     * section can be placed independently of the main .data section.
-     */
-    .data . : {
-        __DATA_RAM_START__ = .;
-        *(SORT_BY_ALIGNMENT(.data*))
-        __DATA_RAM_END__ = .;
-    } >RAM AT>ROM
+    DATA_SECTION >RAM AT>ROM
+    __DATA_RAM_START__ = __DATA_START__;
+    __DATA_RAM_END__ = __DATA_END__;
 
     /*
      * .rela.dyn needs to come after .data for the read-elf utility to parse
diff --git a/bl2u/bl2u.ld.S b/bl2u/bl2u.ld.S
index 3ab4382..a7752a4 100644
--- a/bl2u/bl2u.ld.S
+++ b/bl2u/bl2u.ld.S
@@ -79,17 +79,7 @@
      */
     __RW_START__ = . ;
 
-    /*
-     * .data must be placed at a lower address than the stacks if the stack
-     * protector is enabled. Alternatively, the .data.stack_protector_canary
-     * section can be placed independently of the main .data section.
-     */
-    .data . : {
-        __DATA_START__ = .;
-        *(SORT_BY_ALIGNMENT(.data*))
-        __DATA_END__ = .;
-    } >RAM
-
+    DATA_SECTION >RAM
     STACK_SECTION >RAM
     BSS_SECTION >RAM
     XLAT_TABLE_SECTION >RAM
diff --git a/bl31/bl31.ld.S b/bl31/bl31.ld.S
index 94d03e3..11e86a3 100644
--- a/bl31/bl31.ld.S
+++ b/bl31/bl31.ld.S
@@ -114,16 +114,7 @@
      */
     __RW_START__ = . ;
 
-    /*
-     * .data must be placed at a lower address than the stacks if the stack
-     * protector is enabled. Alternatively, the .data.stack_protector_canary
-     * section can be placed independently of the main .data section.
-     */
-   .data . : {
-        __DATA_START__ = .;
-        *(SORT_BY_ALIGNMENT(.data*))
-        __DATA_END__ = .;
-    } >RAM
+    DATA_SECTION >RAM
 
     /*
      * .rela.dyn needs to come after .data for the read-elf utility to parse
diff --git a/bl32/sp_min/sp_min.ld.S b/bl32/sp_min/sp_min.ld.S
index 8e91cec..9e0596f 100644
--- a/bl32/sp_min/sp_min.ld.S
+++ b/bl32/sp_min/sp_min.ld.S
@@ -91,11 +91,7 @@
      */
     __RW_START__ = . ;
 
-    .data . : {
-        __DATA_START__ = .;
-        *(.data*)
-        __DATA_END__ = .;
-    } >RAM
+    DATA_SECTION >RAM
 
 #ifdef BL32_PROGBITS_LIMIT
     ASSERT(. <= BL32_PROGBITS_LIMIT, "BL32 progbits has exceeded its limit.")
diff --git a/bl32/tsp/tsp.ld.S b/bl32/tsp/tsp.ld.S
index 7428c03..bdcd2cf 100644
--- a/bl32/tsp/tsp.ld.S
+++ b/bl32/tsp/tsp.ld.S
@@ -70,11 +70,7 @@
      */
     __RW_START__ = . ;
 
-    .data . : {
-        __DATA_START__ = .;
-        *(.data*)
-        __DATA_END__ = .;
-    } >RAM
+    DATA_SECTION >RAM
 
     /*
      * .rela.dyn needs to come after .data for the read-elf utility to parse
diff --git a/include/common/bl_common.ld.h b/include/common/bl_common.ld.h
index 8ea7d6a..97fed72 100644
--- a/include/common/bl_common.ld.h
+++ b/include/common/bl_common.ld.h
@@ -17,6 +17,10 @@
 #define BSS_ALIGN	8
 #endif
 
+#ifndef DATA_ALIGN
+#define DATA_ALIGN	1
+#endif
+
 #define CPU_OPS						\
 	. = ALIGN(STRUCT_ALIGN);			\
 	__CPU_OPS_START__ = .;				\
@@ -85,6 +89,18 @@
 	GOT						\
 	BASE_XLAT_TABLE_RO
 
+/*
+ * .data must be placed at a lower address than the stacks if the stack
+ * protector is enabled. Alternatively, the .data.stack_protector_canary
+ * section can be placed independently of the main .data section.
+ */
+#define DATA_SECTION					\
+	.data . : ALIGN(DATA_ALIGN) {			\
+		__DATA_START__ = .;			\
+		*(SORT_BY_ALIGNMENT(.data*))		\
+		__DATA_END__ = .;			\
+	}
+
 #define STACK_SECTION					\
 	stacks (NOLOAD) : {				\
 		__STACKS_START__ = .;			\
diff --git a/plat/mediatek/mt6795/bl31.ld.S b/plat/mediatek/mt6795/bl31.ld.S
index 91ca87c..3d881fc 100644
--- a/plat/mediatek/mt6795/bl31.ld.S
+++ b/plat/mediatek/mt6795/bl31.ld.S
@@ -59,16 +59,7 @@
      */
     __RW_START__ = . ;
 
-    /*
-     * .data must be placed at a lower address than the stacks if the stack
-     * protector is enabled. Alternatively, the .data.stack_protector_canary
-     * section can be placed independently of the main .data section.
-     */
-    .data . : {
-        __DATA_START__ = .;
-        *(.data*)
-        __DATA_END__ = .;
-    } >RAM
+    DATA_SECTION >RAM
 
 #ifdef BL31_PROGBITS_LIMIT
     ASSERT(. <= BL31_PROGBITS_LIMIT, "BL3-1 progbits has exceeded its limit.")