[Intel-gfx] PANEL_FITTING atom

[Jesse Barnes]

On Monday, August 4, 2008 7:11 pm Lovelace Luquette wrote:
> On Mon, 4 Aug 2008, Jesse Barnes wrote:
> > On Monday, August 04, 2008 6:40 am Lovelace Luquette wrote:
> >> Hi,
> >>
> >> I'm using an Intel i852GM chipset and have a 16:10 aspect ratio LCD.
> >>
> >> I'd like to be able to configure the PANEL_FITTING atom introduced in
> >> 2.3. However, looking through the code, I see that the PANEL_FITTING
> >> atom is disabled for all of the i8xx chips.  For these chips all I can
> >> do is accept the default setting of PANEL_FITTING = full.
> >>
> >> The code for letterboxing/pillar-boxing seems to be really simple. 
> >> (Even for i8xx chips, it seems like all we have to do is set
> >> PFIT_CONTROL to the appropriate mode, then find the drawing offset and
> >> store it in
> >> PFIT_PGM_RATIOS).
> >>
> >> Is the reason we can't implement the PANEL_FITTING atom for i8xx because
> >> the i8xx chips don't have the PFIT_CONTROL and PFIT_PGM_RATIOS
> >> registers? (As a side note: this doesn't seem to be the case since all
> >> of the PFIT_* registers are declared in i810_regs.h.  As another side
> >> note, when I dump the chip's registers I see PFIT_CONTROL and
> >> PFIT_PGM_RATIOS in the dump.)
> >
> > Right, and I think we saw PFIT programming cause trouble on at least a
> > few 8xx platforms (even though they appeared to have PFIT regs).
> >
> >> I found the register documentation at http://intellinuxgraphics.org for
> >> 965+ chips; is there a similar place to find register documentation for
> >> older chips or has intel not released that data?
> >
> > Our internal 8xx documentation doesn't list the PFIT regs, though on some
> > chips they may work anyway.  If they work fine for you after removing the
> > 8xx checks in the PFIT code, we could add a whitelist for your platform
> > to make things work automatically.
>
> Alright, I'll see what it does on my platform.
>
> If the PFIT_* registers don't end up working, is there any other way I
> could get around the full-x/y scaling method?

Any news here?  I'm not sure of an easy way to get other pfit modes w/o using 
the panel scaler.  Maybe there's an external one on your platform?

Jesse