Re: [PATCH v4] arm: rockchip: spl: Add hotkey detection support.

Hi Valentin,

On 8/20/2026 6:27 PM, Valentin Liu wrote:
> Add a configurable Rockchip SPL hotkey feature that checks the
> serial console during SPL startup.
> 
> Ctrl+B can be used to enter MaskROM mode and be widely used.
> Ctrl+D can be used to enter Loader mode, Ctrl+F for Fastboot mode.
> We can add more boot mode support in future.

Why the need to have special hotkey handling in SPL?

I would rather see that we extend TPL/SPL/proper with support for
reading any 'syscon-reboot-mode' reg and act according to that.

Also think there is a series on list to extend the reset command to
accept a reboot-mode.

That way we would be able to reboot from OS or U-Boot proper into
maskrom (or any other) mode, instead of trying to implement platform
specific hotkey handling.

Regards,
Jonas

> 
> Add CONFIG_SPL_ROCKCHIP_HOTKEY to enable the feature and wait for
> the serial port to be ready to receive input before checking for
> hotkeys.
> 
> Signed-off-by: Valentin Liu <[email protected]>
> ---
> Changes for v2:
> - Simplify the dependencies of SPL_ROCKCHIP_HOTKEY.
> - Remove the conditions for the newly added includes.
> ---
> Changes for v3:
> - Add a dummy spl_hotkey_init() to avoid undefined reference errors
>   when building without CONFIG_SPL_ROCKCHIP_HOTKEY.
> ---
> Changes for v4:
> - Add condition of CONFIG_ROCKCHIP_BOOT_MODE_REG != 0 to prevent
>   SPL hotkey be compiled and used on unsupported platforms.
> - Add more hotkey support (Ctrl+D and Ctrl+F).
> - Remove prints on the standard path.
> - Add some code comment.
> 
>  arch/arm/mach-rockchip/Kconfig | 14 +++++++++
>  arch/arm/mach-rockchip/spl.c   | 54 ++++++++++++++++++++++++++++++++++
>  2 files changed, 68 insertions(+)

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