desktop wrapped to left side

[Dirk Thierbach]

Kim Wroblewski wrote:

> Using nv 1.2.0 driver at 3840x2400 brings up the desktop with the
> right 1" wrapped on the left side of the screen. The hardware cursor
> remains at the normal position, while the soft-cursor is wrapped
> along with the rest of the desktop.

> any ideas where I could start looking into this?

> Using the same modeline with the nvidia driver (both 8774 and 9625)
> the screen is drawn correctly, not wrapped. So I suspect the problem
> has something todo with the nv driver itself. With the nv driver
> everything works normally, it's just shifted over a few hundred
> pixels.

Last time I looked, the 'nv' and the 'nvidia' driver differed by one
(i.e., 8 pixels) in the way they write the horizontal sync  to the CRTC
registers. But that doesn't explain the huge wrap. 

Also, for different cards, NVidia has extended the bit width of the
horizontal and vertical values, and has put the extra bits into various
new registers. It's possible that for such a huge resolution, some of
the most significant bits are not written using the 'nv' driver (or
the driver doesn't recognize it can do that with your card).  And with
a wrong horizontal sync, the screen will move to the side or wrap.
The soft-cursor is part of the framebuffer and will of course also wrap.

Look at your modeline and the current source (NVDACInit in nv_dac.c, 
NVLoadStateExt in nv_hw.c) and check if this is the case. Dumping
the CRTC registers with the values the 'nvidia' driver sets may also help.

- Dirk