[U-Boot] [PATCH v3 17/18] x86: Add a way to jump from TPL to SPL

[Simon Glass]

When TPL finishes it needs to jump to SPL with the stack set up correctly.
Add a function to handle this.

Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
---

Changes in v3: None
Changes in v2:
- Add a new patch allowing jumping from TPL to SPL

 arch/x86/cpu/start.S | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index 30fa7def464..4a82add76b7 100644
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -190,6 +190,19 @@ board_init_f_r_trampoline:
 	/* Re-enter U-Boot by calling board_init_f_r() */
 	call	board_init_f_r
 
+#ifdef CONFIG_TPL
+.globl jump_to_spl
+.type jump_to_spl, @function
+jump_to_spl:
+	/* Reset stack to the top of CAR space */
+	movl	$(CONFIG_SYS_CAR_ADDR + CONFIG_SYS_CAR_SIZE - 4), %esp
+#ifdef CONFIG_DCACHE_RAM_MRC_VAR_SIZE
+	subl	$CONFIG_DCACHE_RAM_MRC_VAR_SIZE, %esp
+#endif
+
+	jmp	*%eax
+#endif
+
 die:
 	hlt
 	jmp	die
-- 
2.21.0.1020.gf2820cf01a-goog