Also, most device functions related to IRQ handling no longer take a device
pointer. We make so many assumptions about the machine's layout in irq.c that
this just seemed silly.
The architecture here follows that of the vax port -- each device has its
evcnt in its softc, but defers actually incrementing it to the IRQ
dispatcher. This way, devices can attach sub-counts (e.g. Rx and Tx counts
for Ethernet interfaces), but don't all have to have code to increment the
counters.
Drivers deliberately call evcnt_attach_dynamic() before establishing their
interrupt handler so that the establish routine can attach a parent event if
that's appropriate. At present, it isn't.
NULL "name" argument to irq_establish indicates that the device will maintain
an evcnt structure for this interrupt. In this case, irq_establish will still
maintain its own count (for DDB machine irqstat), but won't attach it to the
global list.
Change use of ev_group and ev_name to follow guidelines in evcnt(9).
Switch arckbd(4) over to the new arrangements.
