[SeaBIOS] [PATCH] src/bootsplash.c: Fix displaying VGA bootsplash

Gerhard Wiesinger lists at wiesinger.com
Wed Feb 15 07:54:15 CET 2012

On Tue, 14 Feb 2012, Kevin O'Connor wrote:

> On Tue, Feb 14, 2012 at 06:37:18AM +0100, Gerhard Wiesinger wrote:
>> On Mon, 13 Feb 2012, Kevin O'Connor wrote:
>>> On Mon, Feb 13, 2012 at 07:42:52AM +0100, Gerhard Wiesinger wrote:
>>>> VGA bootsplash isn't displayed because video mode is set
>>>> which clears the display. Video mode has already been set
>>>> by the VGA BIOS.
>>> The experience from running on real hardware has indicated that a real
>>> off-the-shelf BIOS will init the display and clear the screen at
>>> startup.  We've seen real off-the-shelf vgabios do weird things if the
>>> BIOS doesn't init and clear the screen.
>> But on real hardware one CAN SEE init string display of e.g. NVIDIA
>> and AMD cards (some do also a beep after VGA display or on BIOS
>> init). Also screen is cleared afterwards. Maybe there is a short
>> delay in VGA BIOS/BIOS.
> This would be for the vgabios to do.  I certainly wouldn't encourage
> it though, as I don't much like boot delays.
>> Another possibility would be to add it as option in the build
>> process. I've already defined an #ifdef therefore.
>> Maybe an optional delay (config option) before setting video mode
>> would also be fine.
> I would really prefer to have one code path for all platforms.  I
> don't see much value in seeing the vgabios screen - certainly not
> enough to add delays to the boot.

I agree, delay isn't the best thing. I think having just another compile 
time config option is the best choice and doesn't hurt anyone if default 
behaviour is "without change". Prepared another patch. Will post it.

BTW: I don't get anything from seabios mailing list, subscription was ok.



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