Change stub example to use asm-generic/sections.h

We can use the declarations of __bss_start and _end from this header
instead of declaring them locally.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/mips/include/asm/u-boot-mips.h

@@ -7,7 +7,7 @@
 
 static inline unsigned long bss_start(void)
 {
-	extern ulong __bss_start;
+	extern char __bss_start[];
 	return (unsigned long) &__bss_start;
 }
 
@@ -19,7 +19,7 @@ static inline unsigned long bss_end(void)
 
 static inline unsigned long image_copy_end(void)
 {
-	extern ulong __image_copy_end;
+	extern char __image_copy_end[];
 	return (unsigned long) &__image_copy_end;
 }
 

arch/nds32/include/asm/u-boot-nds32.h

@@ -30,10 +30,10 @@
 #define _U_BOOT_NDS32_H_	1
 
 /* for the following variables, see start.S */
-extern ulong __bss_start;	/* BSS start relative to _start */
-extern ulong __bss_end;	/* BSS end relative to _start */
-extern ulong _end;		/* end of image relative to _start */
-extern ulong _start;		/* start of image relative to _start */
+extern char __bss_start[];	/* BSS start relative to _start */
+extern ulong __bss_end;		/* BSS end relative to _start */
+extern char _end[];		/* end of image relative to _start */
+extern void _start(void);	/* start of image relative to _start */
 extern ulong _TEXT_BASE;	/* code start */
 extern ulong IRQ_STACK_START;	/* top of IRQ stack */
 extern ulong FIQ_STACK_START;	/* top of FIQ stack */

arch/x86/include/asm/u-boot-x86.h

@@ -25,13 +25,13 @@
 #define _U_BOOT_I386_H_	1
 
 /* Exports from the Linker Script */
-extern ulong __text_start;
+extern char __text_start[];
 extern ulong __data_end;
 extern ulong __rel_dyn_start;
 extern ulong __rel_dyn_end;
-extern ulong __bss_start;
+extern char __bss_start[];
 extern ulong __bss_end;
-extern ulong _end;
+extern char _end[];
 
 /* cpu/.../cpu.c */
 int x86_cpu_init_r(void);

examples/standalone/stubs.c

@@ -217,16 +217,15 @@ void __attribute__((unused)) dummy(void)
 #include <_exports.h>
 }
 
-extern unsigned long __bss_start, _end;
+#include <asm/sections.h>
 
 void app_startup(char * const *argv)
 {
-	unsigned char * cp = (unsigned char *) &__bss_start;
+	char *cp = __bss_start;
 
 	/* Zero out BSS */
-	while (cp < (unsigned char *)&_end) {
+	while (cp < _end)
 		*cp++ = 0;
-	}
 
 #if defined(CONFIG_X86)
 	/* x86 does not have a dedicated register for passing global_data */