[U-Boot] [PATCH v2 11/47] x86: Tidy up global_data flags

Simon Glass sjg at chromium.org
Fri Jul 31 17:31:28 CEST 2015


These flags now overlap some global ones. Adjust the x86-specific flags to
avoid this. Since this requires a change to the start.S code, add a way for
tools to find the 32-bit cold reset entry point. Previously this was at a
fixed offset.

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

Changes in v2:
- Add a marker for the cold reset entry point
- Use the now-defined top 16-bits of the global_data flags

 arch/x86/cpu/start.S               | 8 ++++++--
 arch/x86/include/asm/global_data.h | 8 ++++----
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index 7ef8b88..9b2584d 100644
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -41,14 +41,18 @@ _x86boot_start:
 	wbinvd
 
 	/* Tell 32-bit code it is being entered from an in-RAM copy */
-	movw	$GD_FLG_WARM_BOOT, %bx
+	movl	$GD_FLG_WARM_BOOT, %ebx
 	jmp	1f
+
+	/* Add a way for tools to discover the _start entry point */
+	.align	4
+	.long	0x12345678
 _start:
 	/*
 	 * This is the 32-bit cold-reset entry point, coming from start16.
 	 * Set %bx to 0 to indicate this.
 	 */
-	movw	$GD_FLG_COLD_BOOT, %bx
+	movl	$GD_FLG_COLD_BOOT, %ebx
 1:
 	/* Save BIST */
 	movl	%eax, %ebp
diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
index 4d9eac6..3db9a4c 100644
--- a/arch/x86/include/asm/global_data.h
+++ b/arch/x86/include/asm/global_data.h
@@ -87,14 +87,14 @@ static inline __attribute__((no_instrument_function)) gd_t *get_fs_gd_ptr(void)
 
 #define gd	get_fs_gd_ptr()
 
+#define DECLARE_GLOBAL_DATA_PTR
+
 #endif
 
 /*
  * Our private Global Data Flags
  */
-#define GD_FLG_COLD_BOOT	0x00100	/* Cold Boot */
-#define GD_FLG_WARM_BOOT	0x00200	/* Warm Boot */
-
-#define DECLARE_GLOBAL_DATA_PTR
+#define GD_FLG_COLD_BOOT	0x10000	/* Cold Boot */
+#define GD_FLG_WARM_BOOT	0x20000	/* Warm Boot */
 
 #endif /* __ASM_GBL_DATA_H */
-- 
2.5.0.rc2.392.g76e840b



More information about the U-Boot mailing list