x86: Place global data below stack before entering C
By reserving space for the Global Data immediately below the stack during
assembly level initialisation, the C declaration of the static global data
can be removed, along with the 'RAM Bootstrap' function. This results in
cleaner code, and the ability to pass boot-up flags from assembler into C
diff --git a/arch/i386/cpu/start.S b/arch/i386/cpu/start.S
index 66ff4f3..cff4637 100644
--- a/arch/i386/cpu/start.S
+++ b/arch/i386/cpu/start.S
@@ -25,6 +25,7 @@
#include <config.h>
#include <version.h>
+#include <asm/global_data.h>
.section .text
@@ -127,6 +128,13 @@
/* Set the upper memory limit parameter */
subl $CONFIG_SYS_STACK_SIZE, %eax
+ /* Reserve space for global data */
+ subl $(GD_SIZE * 4), %eax
+
+ /* %eax points to the global data structure */
+ movl %esp, (GD_RAM_SIZE * 4)(%eax)
+ movl %ebx, (GD_FLAGS * 4)(%eax)
+
call board_init_f /* Enter, U-boot! */
/* indicate (lack of) progress */