On 4/13/07, Patrick McNamara <[EMAIL PROTECTED]> wrote:
Timothy Normand Miller wrote:
[snip]
> > Perhaps it would just be simpler to always set the interrupt in the > right instruction and have a mask bit in the global config registers. > I would certain argue for the second option. It may take slightly more hardware to do, but it is certainly the simpler and more portable solution. I don't know if we have discussed how video controller microcode is uploaded or changed, but enabling/disabling the interrupt should a PIO operation I think. The reason for this is the expectation the system may have surrounding the toggling of interrupts. If it is done as a DMA command to the card, it could be some time before the DMA completes, especially if there is a large transfer of some sort currently in progress. If interrupts need to be disabled, they generally need to be disabled immediately, not some "random" time in the future.
I completely agree. In fact, it's being handled entirely via PIO at the moment anyhow, since we don't have a DMA engine. The DMA engine may (when the right privileges are set) have access to every register, but at least by convention, we won't use DMA for certain things. -- 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)
