Re: Synchronized MMIO access on SMP

[Niklas H�glund]

On Mon, Oct 04, 1999 at 10:26:29AM -0400, James Simmons wrote:
> Good point. Have to look at a way to handle this. I have started to
> rewrite the schedular to handle this. I realized this is not a problem for
> just video cards but really any device that has MMIO. On a SMP machine you
> could have two processors access the MMIO at the same time causing the
> card to go into a indetermined state. Also with some cards they might have
> more than one MMIO area and each MMIO area thats accessed can effect the
> card in such a way that the results you expected from another MMIO
> region might not be what you want. Well I going to take this to the MM
> guys to figure out away to handle this. 

I guess most other hardware are only accessed from kernel device
drivers that have internal locking.

-- 
                                                Niklas