Modules and Buses

[M. Warner Losh]

In message: <20100819170643.38362078.ray at dlink.ua>
            Alexandr Rybalko <ray at dlink.ua> writes:
: On Thu, 19 Aug 2010 09:18:46 -0400
: John Baldwin <jhb at freebsd.org> wrote:
: 
: >> On Thursday, August 19, 2010 8:38:05 am Alexandr Rybalko wrote:
: >> > Hi all,
: >> > 
: >> > Can someone say, how `make` in sys/modules dir can obtain available buses.
: >> > I try to make clean version of bfe, that can be for PCI bus or can be part 
: >> of SoC (like BCM5354) on SSB bus.
: >> > So for proper module building I need to know what bus interface I must build 
: >> if_bfe_pci.c, or if_bfe_siba.c, or both?
: >> 
: >> You can always include both buses.  If a bus driver isn't present in the 
: >> kernel the attachment will just never be invoked.
: 
: I was afraid of such response. Now I have to rewrite siba implementation to newbus :)
: Thanks you for answer! 

In the module building system (modules built with sys/modules
Makefiles), we generally include all relevant busses.  So, for i386 we
include EISA front ends for some devices, but omit that on amd64.  For
siba, you'd only include it on mips, since that's the only platform
where this would be relevant (I know broadcom wireless drivers are
implemented via a pci <-> siba bridge, but that's a really special
case).

Check out sys/modules/ep for an example from the mists of history..

Warner