sb600/sb700 ohci experimental patch
avg at freebsd.org
Mon Sep 28 13:55:49 UTC 2009
on 28/09/2009 14:48 John Baldwin said the following:
> I don't think you can do this because it is a "feature" to not disable SMM if
> ohci(4) is not loaded so that a USB keyboard works when the USB driver isn't
> loaded via PS/2 emulation, even when the OS is running.
Very good point.
> I am curious if we
> really need to do the handover for each controller or if disabling it for
> ohci0 effectively disables it for all controllers? What do other OS's do?
Don't have an answer about other OSes.
But OHCI controllers have individual "used by SMM" bits and taking over one
controller doesn't affect the bits of the other controllers - they remain set.
Not that it means that SMM code actually keeps on controlling them.
Actually, just checked - Linux also does it per controller:
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