Re: Help with X on iBook?
Benjamin Herrenschmidt wrote:
>
> >On Mon, 26 Feb 2001, Michel Dänzer wrote:
> >> I just had an interesting idea: The flat panel code could never
> >determine the
> >> panel dimensions because our machines don't have a BIOS. So I
> specified them
> >> with
> >>
> >> Option "PanelWidth" "1024"
> >> Option "PanelHeight" "768"
> >>
> >> and it works without any of the options I have mentioned here a thousand
> >> times! (iBook users will have to use 800 and 600 of course) This kind of
> >> enables mode switching, but everyone should be aware that *this may
> >> damage your panel* . You've been warned.
> >>
> >>
> >> Now I just wonder if we could detect the panel dimensions somehow...
> >
> >From the OF device tree? And return it to userspace using a new fbdev
> ioctl()?
>
> Unfortunately, the OF ATI drivers won't give you anything useful in the
> device-tree (not even the PLL & clock values). There should probably be a
> way to probe the panel type, but I'm not too sure how. For the PLL &
> clock values, the only solution I have (suggested by ATI) would be to
> build a big table indexed by the OF name of the card that contains the
> ref clocks (the divider can be read from the registers) and eventually
> the min/max PLL values. A table based on the machine model can probably
> be used for the LCD size (but beware that wallstreet exist in both
> 800x600 passive matrix and 1024x768 active & passive matrix). I beleive
> new LVDS displays can be probed but I don't know how.
>
> You can't even rely on the resolution returned by the OF driver as, at
> least on my pismo, it's able to use a scaled mode for booting if asked to
> do so by the nvram settings.
*sigh*
> I tried the above options and indeed, it works. However, if I then allow
> X to use 800x600 (and other resolutions like 640x480), the scaler doesn't
> seem to be properly configured. It's readable, but the display is
> somewhat clipped and have a vertical band at the 3/4 of the screen that
> wraps part of it. (Difficult to explain what I see... doesn't look far
> from beeing correct however).
Yup, seen that too - it used to be like this in 32 bit but better in 16 bit.
:(
--
Earthling Michel Dänzer (MrCooper) \ Debian GNU/Linux (powerpc) developer
CS student, Free Software enthusiast \ XFree86 and DRI project member
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