X Video, XvPutVideo: ATI Radeon M7 Bus Mastering corrupts video capture buffer

John Klingler john at jupiter.com
Mon Nov 6 11:22:34 PST 2006

When using M7 bus mastering to DMA data from the video capture buffer 
the data gets corrupted, developing severe motion artifacts.

I verified that the problem is at the source by setting the M7's overlay 
buffer to coincide with the capture buffer. There is no problem until 
you start the DMA.

I did not have this problem with the ATI M3. The ATI M7 driver for 
Windows also does not have this problem. The bus mastering code I use is 
the same so the problem appears to be elsewhere, probably in the 

Does anyone have some experience with, or insight into this?

John Klingler

More information about the xorg mailing list