[PATCH v2 2/6] rockchip: Use an external TPL binary on RK3568

[Jagan Teki]

On Tue, Feb 14, 2023 at 4:03 PM Jonas Karlman <jonas at kwiboo.se> wrote:
>
> Rockchip SoCs typically use U-Boot TPL to initialize DRAM, then jumps
> back to BootRom to load next stage, U-Boot SPL, into DRAM. BootRom then
> jumps to U-Boot SPL to continue the normal boot flow.
>
> However, there is no support to initialize DRAM on RK35xx SoCs using
> U-Boot TPL and instead an external TPL binary must be used to generate a
> bootable u-boot-rockchip.bin image.
>
> Add CONFIG_ROCKCHIP_EXTERNAL_TPL to indicate that an external TPL should
> be used. Build U-Boot with ROCKCHIP_TPL=/path/to/ddr.bin to generate a
> bootable u-boot-rockchip.bin image for RK3568.

Please add documentation in doc/board/rockchip/rockchip.rst and take
an example of a real DDR bin from rkbin.

Jagan.