If we would like to boot from SD card, we have to implement mmc driver in SPL stage, and get a slightly larger spl binrary. RK3288's bootrom code has the ability to load spl and u-boot. This patch tasks maskrom to load u-boot.
Loading sequence after rework: bootrom ==> spl ==> bootrom ==> u-boot
Signed-off-by: Ziyuan Xu xzy.xu@rock-chips.com --- arch/arm/mach-rockchip/rk3288/save_boot_param.S | 32 +++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 arch/arm/mach-rockchip/rk3288/save_boot_param.S
diff --git a/arch/arm/mach-rockchip/rk3288/save_boot_param.S b/arch/arm/mach-rockchip/rk3288/save_boot_param.S new file mode 100644 index 0000000..778ec83 --- /dev/null +++ b/arch/arm/mach-rockchip/rk3288/save_boot_param.S @@ -0,0 +1,32 @@ +/* + * (C) Copyright 2015 Google, Inc + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <linux/linkage.h> + +.globl SAVE_SP_ADDR +SAVE_SP_ADDR: + .word 0 + +/* + * void save_boot_params + * + * Save sp, lr, r1~r12 + */ +ENTRY(save_boot_params) + push {r1-r12, lr} + ldr r0, =SAVE_SP_ADDR + str sp, [r0] + b save_boot_params_ret @ back to my caller +ENDPROC(save_boot_params) + + +.globl back_to_bootrom +ENTRY(back_to_bootrom) + ldr r0, =SAVE_SP_ADDR + ldr sp, [r0] + mov r0, #0 + pop {r1-r12, pc} +ENDPROC(back_to_bootrom)