[LinuxBIOS] LinuxTag Berlin 29/5-2/6
libv at skynet.be
Sun May 27 00:50:43 CEST 2007
On Sat, May 26, 2007 at 05:29:28PM +0200, Stefan Reinauer wrote:
> > No, this is purely to get 640x480 textmode to work on the CRT
> > connection. This is the safe option that will work for 98% of the EPIA-M
> > users out there. The other 2% are those who are fully dependant on the
> > DVI or LVDS/RGB display modules.
> Or they will just use the VGA BIOS which can do all, I think.
Well, VIAs VGA BIOS is table based and not always the right solution.
> > I can of course insert a full modesetting system, but that will mean
> > doing things like EDID parsing and cvt modeline generation in linuxbios.
> > And this will all be getting rather big rather quickly.
> Does VIA's graphics bios do all that? Can it be done in a non-VIA-only
It only does some rudimentary EDID parsing and some very basic output
handling, including both CRTCs with scaling and simultaneous (needed to
get 640x400 on a CLE266 with a panel or DVI). It's fully table based
though, so you only get those resolutions and modes that were
programmed. So you can forget about 1360x768, 1440x900 or 1680x1050.
Actually, i have quite a ball on VIAs forums, pointing windows users to
linux. It seems their drivers depend on what is programmed in the BIOS,
and VIa seems utterly unable to fix it without creating new BIOS images
Try finding a manufacturer willing to create a bios with 1680x1050 for a
board for which production stopped in 2005. Then hope that this is the
manufacturer for your exact board :)
> > 640x480 at 60Hz is somewhat safe, as most devices on the CRT connection
> > will be able to handle this, as this is the default BIOS textmode.
> default text mode sucks ;) but ignore me, i'm the bootsplash guy
Well, this textmode is a life-saver. It's perfectly ok to live with only
a mode from X... this right until the time an fsck requires user
intervention, and serial isn't responding (which i had a month or so
ago). You're very glad to see a textmode then.
I'm not sure how you get to busybox in linuxbios when something goes
wrong, but my guess is that anyone will be over the moon when able to
use this directly, even if it's just 640x480.
Nobody will ever be as glad to see a boot splash. It will never save
somebody any time or effort. Besides, i think you need a vga textmode
if you want the kernel to properly log its output without an FB driver.
Not that i'm totally against a bootsplash or a full modeset in BIOS, but
imho other things are way more important.
I will have to do a bit more work than what i'm currently doing though,
i will need to make it possible to use textmode on DVI or a panel on the
CLE266. That way all basic needs are taken care of.
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