x86: fsp: Save stack address to CMOS for next S3 boot

At the end of pre-relocation phase, save the new stack address
to CMOS and use it as the stack on next S3 boot for fsp_init()
continuation function.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/x86/include/asm/u-boot-x86.h b/arch/x86/include/asm/u-boot-x86.h
index d2d603967e..d55455f2d0 100644
--- a/arch/x86/include/asm/u-boot-x86.h
+++ b/arch/x86/include/asm/u-boot-x86.h
@@ -54,6 +54,19 @@ u32 isa_map_rom(u32 bus_addr, int size);
 /* arch/x86/lib/... */
 int video_bios_init(void);
 
+/* arch/x86/lib/fsp/... */
+
+/**
+ * fsp_save_s3_stack() - save stack address to CMOS for next S3 boot
+ *
+ * At the end of pre-relocation phase, save the new stack address
+ * to CMOS and use it as the stack on next S3 boot for fsp_init()
+ * continuation function.
+ *
+ * @return:	0 if OK, -ve on error
+ */
+int fsp_save_s3_stack(void);
+
 void	board_init_f_r_trampoline(ulong) __attribute__ ((noreturn));
 void	board_init_f_r(void) __attribute__ ((noreturn));