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

1 files changed, 22 insertions, 2 deletions

diff --git a/arch/i386/include/asm/global_data.h b/arch/i386/include/asm/global_data.h
index 3a9adc9..456f606 100644
--- a/arch/i386/include/asm/global_data.h
+++ b/arch/i386/include/asm/global_data.h
@@ -33,6 +33,8 @@
  * Keep it *SMALL* and remember to set CONFIG_SYS_GBL_DATA_SIZE > sizeof(gd_t)
  */
 
+#ifndef __ASSEMBLY__
+
 typedef	struct {
 	bd_t		*bd;
 	unsigned long	flags;
@@ -49,6 +51,26 @@ typedef	struct {
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
+extern gd_t *gd;
+
+#endif
+
+/* Word Offsets into Global Data - MUST match struct gd_t */
+#define GD_BD    0
+#define GD_FLAGS 1
+#define GD_BAUDRATE  2
+#define GD_HAVE_CONSOLE  3
+#define GD_RELOC_OFF 4
+#define GD_ENV_ADDR  5
+#define GD_ENV_VALID 6
+#define GD_CPU_CLK 7
+#define GD_BUS_CLK 8
+#define GD_RAM_SIZE  9
+#define GD_RESET_STATUS  10
+#define GD_JT    11
+
+#define GD_SIZE    12
+
 /*
  * Global Data Flags
  */
@@ -61,8 +83,6 @@ typedef	struct {
 #define GD_FLG_DISABLE_CONSOLE	0x00040	/* Disable console (in & out)		*/
 #define GD_FLG_ENV_READY	0x00080	/* Environment imported into hash table	*/
 
-extern gd_t *gd;
-
 #define DECLARE_GLOBAL_DATA_PTR
 
 #endif /* __ASM_GBL_DATA_H */