Re: Help with X on iBook?
>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.
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).
I used XF 4.0.2 from the DRI PCIGART branch.
Ben.
Reply to: