The machine-dependent
cpu_configure() is called during system bootstrap to perform the machine-dependent portion of device autoconfiguration. It sets the configuration machinery in motion by finding the root bus (“mainbus”). When this function returns, interrupts must be enabled.
The following tasks are performed by
cpu_configure():
•
initialize CPU interrupts and SPLs (see
spl(9));
•
call config_rootfound() for “mainbus”; and