Re: [TESTED] tdfx framebuffer garbles display in 2.6.19.5

DervishD
2007-03-14T09:05:52Z

Hi Antonino :)

NEW INFORMATION ABOUT THE PROBLEM

* Antonino A. Daplas <adaplas@gmail.com> dixit:
> On Tue, 2007-03-06 at 07:25 +0100, DervishD wrote:
> > > > With the patch, the scroll slows to a crawl and the system is
> > > > unusable. The time to scroll 30 lines is about a minute or so
> > > > (probably more, I just measured for a while).
> > > >
> > > > If you want me to test other patches, just tell :)
> > >
> > > Can you change the mdelay to udelay and use higher/lower delay values
> > > to see if there's any improvement?
> >
> > Yes, as soon as I can build a new kernel and reboot. Any suggested
> > value?
>
> You can start with 5 and increment by 5. So you need not reboot each
> time, compile tdfxfb as a module, and set CONFIG_HW_CONSOLE_BINDING=y
> (under drivers->char).

Until I discovered how to reproduce the bug, I had to reboot for
each test. But I discovered the real problem...

The garbling doesn't happen, no matter the udelay, until I start X.
Once X is started, even with an udelay(100) (which for me makes the
display untolerably slow) the problem happens.

This doesn't happen in latest 2.4.x, but I remember that some
characters "dissappeared" from the screen at some 2.4.x when X was
running. That was a known bug in the X driver of this card, so I'm not
sure if the last X.Org driver has this problem or not. Unfortunately, I
cannot test this directly, the most I can do is to test under Ubuntu,
which uses an older 2.6.x kernel.

If this new discovery doesn't ring any bell for you, I'll make a
test under Ubuntu and after that I'll just wait until I can upgrade X
(which I cannot do now) to latest X.Org (I'm now using 7.0.22).

Thanks for all your help. I'll keep you informed of any change I
notice, and (although I won't be very fast doing it...) you can count on
me to test any patch you want.