xf86-video-intel: unexpected phenomenon on XV texture adapter with no scaling

[Krzysztof Halasa]

Roland Scheidegger <sroland at tungstengraphics.com> writes:

> With a very quick look at the r600 code, I suggest trying out the
> attached patch to test my theory about half pixel offsets in hardware.
> This could mess though with EXA acceleration, so if you see a bit odd
> corruption don't be surprised :-).

I can now confirm this patch, applied to current Fedora 11
xorg-x11-drv-ati-6.12.2-14 driver, fixes this Xv issue on RV6xx.

I can't see any EXA corruption.

Thanks a lot.

I guess it should be aplied to the repository?

> --- a/src/r6xx_accel.c
> +++ b/src/r6xx_accel.c
> @@ -974,7 +974,7 @@ set_default_state(ScrnInfoPtr pScrn, drmBufPtr ib)
>      EREG(ib, PA_SU_POLY_OFFSET_FRONT_OFFSET,      0);
>  
>      EREG(ib, PA_SU_LINE_CNTL,                     (8 << PA_SU_LINE_CNTL__WIDTH_shift)); /* Line width 1 pixel */
> -    EREG(ib, PA_SU_VTX_CNTL,                      ((2 << PA_SU_VTX_CNTL__ROUND_MODE_shift) |
> +    EREG(ib, PA_SU_VTX_CNTL,                      ((2 << PA_SU_VTX_CNTL__ROUND_MODE_shift) | PIX_CENTER_bit |
>  						   (5 << QUANT_MODE_shift))); /* Round to Even, fixed point 1/256 */
>      EREG(ib, PA_SU_POLY_OFFSET_CLAMP,             0);
>  

-- 
Krzysztof Halasa