[MPlayer-dev-eng] DMA or not DMA

Attila Kinali attila at kinali.ch
Wed Nov 24 17:27:13 CET 2004


On Wed, 24 Nov 2004 10:55:31 -0500
D Richard Felker III <dalias at aerifal.cx> wrote:

> imo the biggest problem is that you have to have some way of knowing
> when the dma is finished so you don't start writing a new frame to the
> buffer before then.

AFAIK that can be polled, eventualy signalled, dunno, have to look
on how dma is done in linux. I should be able to tell you more this
weekend. 

> btw is there any advantage of doing slice-by-slice dma? or would dma
> all be done at the end of the frame?

Both can be done. Though, the smaller the data is, the less advantage
you get from using dma. Though, a 16*y slice is quite big (7kB for
a 320x240 vid)


			Attila Kinali




More information about the MPlayer-dev-eng mailing list