Re: [PATCH 3/4] dummycon: limit Arm console size hack to footbridge

From: Linus Walleij
Date: Fri Jul 07 2023 - 07:33:42 EST


On Fri, Jul 7, 2023 at 11:56 AM Arnd Bergmann <arnd@xxxxxxxxxx> wrote:

> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> The dummycon default console size used to be determined by architecture,
> but now this is a Kconfig setting on everything except ARM. Tracing this
> back in the historic git trees, this was used to match the size of VGA
> console or VGA framebuffer on early machines, but nowadays that code is
> no longer used, except probably on the old footbridge/netwinder since
> that is the only one that supports vgacon.
>
> On machines with a framebuffer, booting with DT so far results in always
> using the hardcoded 80x30 size in dummycon, while on ATAGS the setting
> can come from a bootloader specific override. Both seem to be worse
> choices than the Kconfig setting, since the actual text size for fbcon
> also depends on the selected font.
>
> Make this work the same way as everywhere else and use the normal
> Kconfig setting, except for the footbridge with vgacon, which keeps
> using the traditional code. If vgacon is disabled, footbridge can
> also ignore the setting. This means the screen_info only has to be
> provided when either vgacon or EFI are enabled now.
>
> To limit the amount of surprises on Arm, change the Kconfig default
> to the previously used 80x30 setting instead of the usual 80x25.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Tested this before and after patch and it looks the same on the NetWinder.
Tested-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

The legacy in the cyber2000 FB driver supports pseudocolor which
makes it a bit hard to rewrite into a simple DRM driver, which is something
I could otherwise look into, it's not a very big or complex driver
after all.

Yours,
Linus Walleij