[U-Boot] [U-Boot, v4, 01/66] spl: add a 'return to bootrom' boot method

[Philipp Tomsich]

> Some devices (e.g. the RK3368) have only limited SRAM, but provide
> support for loading the next boot stage after our SPL performs basic
> setup (e.g. DRAM).
> 
> For target systems like these, we add a boot device BOOTROM that will
> invoke a board-specific hook to return to the bootrom (if supported).
> 
> Signed-off-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
> 
> Reviewed-by: Tom Rini <trini at konsulko.com>
> Reviewed-by: Simon Glass <sjg at chromium.org>
> ---
> 
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
> 
>  arch/arm/include/asm/spl.h |  1 +
>  common/spl/Kconfig         | 11 +++++++++++
>  common/spl/Makefile        |  1 +
>  common/spl/spl_bootrom.c   | 27 +++++++++++++++++++++++++++
>  include/spl.h              | 10 ++++++++++
>  5 files changed, 50 insertions(+)
>  create mode 100644 common/spl/spl_bootrom.c
> 

Applied to u-boot-rockchip, thanks!