Re: graphic drivers and simplefb

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Wed, Apr 04, 2018 at 11:50:18PM +0200, Manuel Bouyer wrote:
> On Wed, Apr 04, 2018 at 06:45:12PM -0300, Jared McNeill wrote:
> > This will crash simplefb if the framebuffer is not configured. U-Boot will
> > set status to okay to signal to OS that simplefb handoff is available.
> 
> Doens't simplefb itself check the existence and status in the dtb ?
> AFAIK I have simplefb in my kernel, but u-boot doesn't configure it,
> yet I boot with console=fb and if works ...
> 
> Without this I can't get console to framebuffer when u-boot doens't know
> about it.

looking closer at it I can't see how this change would be a problem.
With this /chosen/stdout-path may point to a path that doens't
exists, or is not okay.
If it's not okay the driver will not attach because the fdt bus logic will
skip it.
It it doesn't exists, fdtbus_get_stdout_phandle() will return -1, which should
prevent of_match_compatible() from matching.
Did I miss something ?

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--