instead of naming devices by ther dynamically assigned device address,
we hash device uniqueue fields from the device descriptor and produce
a 5 digit hex string that will identify the device across machines.
when there is a collision (less than 1% chance with 100 devices),
usbd will append the device address to the name to make it uniqueue
for this machine.
the hname is passed to drivers in the devid argument, which now has
the form addr:hname, where the colon and hname can be omited (for backwards
compatibility).
when the new behaviour isnt desired, nousbhname= environment variable
can be defined giving the old behaviour.
the issues with the previous tsc change where not related to the tsc
but where problems with timesync using an old frequency file. a
patch to fix timesync was commited, so so we reintroduce the *notsc=
again.
we previously used tsc only on cpu kernel. now that
we use it on terminal kernel too, there might be some
surprises ahead.
so make it possible to disable tsc for machines where
the tsc rate is not kept constant across cores or is
dynamically adjusted by power management.
allow the shadow framebuffer (softscreen) to be used with any
vga driver, not just vesa. this removes the ugly scr->paddr = 0
hack employed by vesa driver to force softscreen and adds a
softscreen vgactl message that can switch the feature on and off
at runtime.
softscreen can greatly improve graphics performance when bus
reads are slow even tho it disables hardware acceleration.
