On 9/8/07, Paul Brook <[EMAIL PROTECTED]> wrote: > > PIO regs are nice for debugging and poking at the card state from within a > running machine. However I'm not so sure about actually using them in anything > approaching a real driver. I guess with appropriate abstraction the driver > may be able to use either.
I meant only a prototype driver. Also, the framebuffer driver for the linux kernel might use PIO. > In practice it may be easier to do everything with a fire and forget DMA What do you mean "a fire"? > command queue. Any time you use PIO you're probably going to have to make > sure the DMA command queue is flushed and the card quiescent before you start > poking at state. Sure, and usually, the kernel would arbitrate that. > > For linux at least you've already got the DRM/DRI/Mesa kernel/userspace split, > so I wouldn't expect PIO to gain you anything by way of simplicitly. If you > want to do anything interesting you're already going to have the DMA queues > configured. True. I'll let the Linux experts deal with that. My job is to give them options. -- Timothy Normand Miller http://www.cse.ohio-state.edu/~millerti Open Graphics Project _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
