http://mail-index.netbsd.org/tech-userlevel/2011/08/25/msg005404.html
This is used by disk tools such as disklabel(8) to dynamically decide is
the undelyling platform uses a disklabel-in-mbr-partition or not
(instead of using a compile-time list of ports).
getlabelusesmbr() reads the sysctl kern.labelusesmbr, takes its value from the
machdep #define LABELUSESMBR.
For evbmips, make LABELUSESMBR 1 if the platform uses pmon
as bootloader, and 0 (the previous value) otherwise.
buses. Make non-inline implementations of bus_space(9) and bus_dma(9)
routines and move them to appropriate .c files.
This may leave amigappc in a bad state, sorry. Fortunately, it will be
easy to repair by imitating the bus.h -> bus_{defs,funcs}.h split in
some other PowerPC port.
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.
<http://mail-index.netbsd.org/tech-kern/2010/04/02/msg007941.html>,
divide each machine's bus.h into bus_defs.h (constants & data types)
and bus_funcs.h (macro implementations of bus_space(9) routines and MD
prototypes).
Note that some bus_space(9) routines' implementation will move to .c
files from inline subroutines or macros in .h files.
I've only made the split for machine architectures where there is PCI.
All of the non-PCI-having architectures will require a similar split.
These #include files are not referenced by any (committed) Makefiles or
header files, yet. Changes to Makefiles, to <sys/bus.h>, and to some
more machine-dependent files will dribble in before I throw the switch.
Export non-inline version of pci api for modules (_MODULE is defined).
Fix definition of pc_conf_hook and pc_conf_interrupt.
Switch to using inlines instead of macros.
Switch ibm4xx to use <powerpc/pci_machdep.h>
struct cfdata * -> cfdata_t
use device accessors, use device_private.
some softc/device_t splits (macppc needs a bunch more)
aprint*_dev used considerably more