to check the status property in their probe routines.
Simplebus used to only instantiate its children whose status="okay"
but that was improper behavior, fixed in r261352. Now that it doesn't
check anymore and probes all its children; the children all have to
do the check because really only the children know how to properly
interpret their status property strings.
Right now all existing drivers only understand "okay" versus something-
that's-not-okay, so they all use the new ofw_bus_status_okay() helper.
fdtbus in most cases. This brings ARM and MIPS more in line with existing
Open Firmware platforms like sparc64 and powerpc, as well as preventing
double-enumeration of the OF tree on embedded PowerPC (first through nexus,
then through fdtbus).
This change is also designed to simplify resource management on FDT platforms
by letting there exist a platform-defined root bus resource_activate() call
instead of replying on fdtbus to do the right thing through fdt_bs_tag.
The OFW_BUS_MAP_INTR() and OFW_BUS_CONFIG_INTR() kobj methods are also
available to implement for similar purposes.
Discussed on: -arm, -mips
Tested by: zbb, brooks, imp, and others
MFC after: 6 weeks
