[make-initrd] [PATCH 1/2] plymouth: fix plymouth showing when drm is not ready yet

[Alexey Gladkov]

On Tue, Apr 23, 2024 at 12:51:37PM +0700, antohami at basealt.ru wrote:
> From: Anton Midyukov <antohami at altlinux.org>
> 
> Fix waiting for a real video card when simpledrm is available.
> card0 will disappear when the DRM module of the real video card is
> loaded. Because of this, by the time Plymouth was shown, simpledrm
> was no longer there, and there was no real video card yet.
> 
> Instead of waiting for devices to appear, is proposed to launch
> triggers for subsystems, as is uses in dracut.
> 
> Signed-off-by: Anton Midyukov <antohami at altlinux.org>
> ---
>  features/plymouth/data/etc/rc.d/init.d/plymouth | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/features/plymouth/data/etc/rc.d/init.d/plymouth b/features/plymouth/data/etc/rc.d/init.d/plymouth
> index 20d64011..27d91876 100755
> --- a/features/plymouth/data/etc/rc.d/init.d/plymouth
> +++ b/features/plymouth/data/etc/rc.d/init.d/plymouth
> @@ -19,8 +19,17 @@ start() {
>  	[ -z "${NOSPLASH-}" ] && [ -z "${RDSHELL-}" ] ||
>  		return 0
>  
> -	udevadm settle --timeout=30 --exit-if-exists=/sys/class/drm/card0/dev
> -	udevadm settle --timeout=30 --exit-if-exists=/sys/class/graphics/fb0/dev
> +	# first trigger graphics subsystem
> +	udevadm trigger --action=add --attr-match=class=0x030000 > /dev/null 2>&1
> +	# first trigger graphics and tty subsystem
> +	udevadm trigger --action=add \
> +		--subsystem-match=graphics \
> +		--subsystem-match=drm \
> +		--subsystem-match=tty \
> +		--subsystem-match=acpi \
> +		> /dev/null 2>&1
> +
> +	udevadm settle --timeout=60 2>&1
>  
>  	local pidfile=/run/plymouth/pid

Хоть подход не нравится, но я смирился, что фича plymouth это чёрная дыра.

У меня другой вопрос раз мы смотрим на dracut.

Не стоит ли также скопировать у них код по вычислению tty вместо
хардкода  --tty=/dev/tty1 ?

https://github.com/dracutdevs/dracut/blob/master/modules.d/50plymouth/plymouth-pretrigger.sh#L19-L21

-- 
Rgrds, legion