So, can anyone answer any of the questions below, or do I have to write
drm for multimedia ?
thanks
Vladimir Dergachev
> interface of doing captures. I'm currently working on a new Xv function
> (XvShmGetImage) that will do this, and also when I see some code from your
I am asking about a different problem - not how to get the data from X to
the client, but how to ask drm nicely to make a DMA transfer. I suspect
(!) that I can simply write the correct values into the registers and the
DMA will happen, but I am not clear about the semantics. For example, is
AGP Offset the address from the point of view of video card or something
else ? Do I have to subtract framebuffer address from it ? What is the
significance of card specific drm structures ? Why do we need them ? Why
have a separate area for textures ? Can I modify it dynamically ? (so as
not to reserve 1mb chunk of ram for capture buffer). What drm handles are
for and whether there is a small test app that exercises drm interface
from command line (i.e. not inside Xserver or glx client). What do I do
about IRQ support ? there seems to be no mention of it in drm structures,
but there are a number of IRQs that could occur (vsync, hsync, DMA
completion (several different sources, i.e. 4 VIP, textures, command
processor..)) Each time irq happens the handler needs to acknowledge it or
the system will hang (it will keep entering the handler).
Not to mention: how do I behave nicely w.r.t. other DMA transfers ? Lock
them, flush queues, etc. ?
At the moment I just want a hacked Xserver that does a DMA transfer from
video memory into plain RAM. Or an Xserver with usermode app that does DMA
transfer - I don't care.
_______________________________________________
Dri-devel mailing list
[EMAIL PROTECTED]
https://lists.sourceforge.net/lists/listinfo/dri-devel
