So a kernel with the following configuration changes booted for Al on
his G4 Xserve (based on GENERIC):

Added config for netbsd-wd0 root on wd0a type ffs

Commented out pdcsata* (hmm..  Meant to comment out pdcide*)
Commented out radeonfb* and options RADEONFB_MMAP_BARS.
Commented out fwohci*, ieee1394if*, fwip*, sbp*

I also slightly patched pdcide.c:

Index: pdcide.c
===================================================================
RCS file: /cvsroot/src/sys/dev/pci/pdcide.c,v
retrieving revision 1.24
diff -p -u -r1.24 pdcide.c
--- pdcide.c	16 Nov 2006 01:33:10 -0000	1.24
+++ pdcide.c	20 Jun 2007 17:59:36 -0000
@@ -557,8 +557,13 @@ pdc20265_pci_intr(void *arg)
 			continue;
 		crv = wdcintr(wdc_cp);
 		if (crv == 0)
-			printf("%s:%d: bogus intr\n",
-			    sc->sc_wdcdev.sc_atac.atac_dev.dv_xname, i);
+{ static int akbcnt=0;
+  if (akbcnt++ < 10) {
+			printf("%s:%d: bogus intr (dmastat = %x)\n",
+			    sc->sc_wdcdev.sc_atac.atac_dev.dv_xname, i,
+dmastat);
+  }
+}
 		else
 			rv = 1;
 	}

It did print the bogus intr message 10 times, but continued through
the boot.

Anyone have time and resources to look into these things?

-allen

-- 
Allen Briggs  |  http://www.ninthwonder.com/~briggs/  |  briggs@ninthwonder.com