This is only for people building kernels with the current if_sn today.
You'll probably want these diffs (which won't be available until the
next supscan in 20 hours or so...).  I was a bit hasty in removing both
calls to physaccess.

Cheers,
-allen

Index: if_sn.c
===================================================================
RCS file: /cvsroot/src/sys/arch/mac68k/dev/if_sn.c,v
retrieving revision 1.4
retrieving revision 1.6
diff -c -r1.4 -r1.6
*** if_sn.c	1997/03/17 04:57:56	1.4
--- if_sn.c	1997/03/17 13:11:24	1.6
***************
*** 1,4 ****
! /*	$NetBSD: if_sn.c,v 1.4 1997/03/17 04:57:56 briggs Exp $	*/
  
  /*
   * National Semiconductor  SONIC Driver
--- 1,4 ----
! /*	$NetBSD: if_sn.c,v 1.6 1997/03/17 13:11:24 briggs Exp $	*/
  
  /*
   * National Semiconductor  SONIC Driver
***************
*** 9,17 ****
   * This driver has been substantially modified since Algorithmics donated
   * it.
   *
!  *   Dennis Gentry <denny1@home.com>
   * and also
!  *   Takeshi Yanagisawa <yanagisw@aa.ap.titech.ac.jp>
   * did the work to get this running on the Macintosh.
   */
  
--- 9,17 ----
   * This driver has been substantially modified since Algorithmics donated
   * it.
   *
!  *   Denton Gentry <denny1@home.com>
   * and also
!  *   Yanagisawa Takeshi <yanagisw@aa.ap.titech.ac.jp>
   * did the work to get this running on the Macintosh.
   */
  
***************
*** 126,131 ****
--- 126,137 ----
  	int		i;
  
  	sc->sc_csr = (struct sonic_reg *) sc->sc_regh;
+ 
+ /*
+  * Disable caching on the SONIC's data space.
+  */
+ 	physaccess((caddr_t) sc->space, (caddr_t) kvtop((caddr_t) sc->space),
+ 		sizeof(sc->space), PG_V | PG_RW | PG_CI);
  
  /*
   * Put the pup in reset mode (sninit() will fix it later)