How difficult would it be to port the ral driver from FreeBSD?

Matthew Dillon dillon at
Mon May 16 12:30:42 PDT 2005

:> > over. I've never worked on device drivers before,
:> > but I'm a fair C programmer, and I have some time
:> > on my hands. I'm willing to do most of the work if
:> > someone is willing to point me in the right direction
:> > and answer some questions.
:> The biggest problem with porting from NetBSD / OpenBSD
:> is the different config mechanism (newbus vs. autoconf)
:> and the difference in the bus_dma abstraction. I don't
:> know if ral was ported to FreeBSD, if so, it should be
:> very easy to get to DragonFly as well.
:> Joerg
:Good, I'll get net access on Wednesday (I just moved), 
:and I'll get the drivers then from FreeBSD and OpenBSD, 
:and I'll use them as a reference to get started. If I have 
:any questions, I'll ask the list, but If the API's haven't 
:changed much, then I don't think the task is beyond me.

    I concur.  It should not be a big deal to port a driver.  BUSDMA
    is the most complex part.  Everything else is basically just minor
    changes (usually the removal of) arguments to procedures.  The
    cdevsw structure has changed considerably but the default case is
    very close to what's in the other OS's and there are numerous examples
    of it in our device code.

					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>

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