Index: radeon_pci.c
===================================================================
RCS file: /cvsroot/src/sys/external/bsd/drm2/radeon/radeon_pci.c,v
retrieving revision 1.4
diff -p -u -r1.4 radeon_pci.c
--- radeon_pci.c	26 Jul 2014 07:36:09 -0000	1.4
+++ radeon_pci.c	14 Feb 2015 06:17:32 -0000
@@ -82,6 +82,9 @@ struct radeon_softc {
 	}				sc_task_u;
 	struct drm_device		*sc_drm_dev;
 	struct pci_dev			sc_pci_dev;
+	/* XXX Used to claim the VGA device before attach_real */
+	bus_space_handle_t		sc_temp_memh;
+	bool				sc_temp_set;
 };
 
 struct radeon_device *
@@ -165,6 +168,15 @@ radeon_attach(device_t parent, device_t 
 	sc->sc_dev = NULL;
 	sc->sc_pa = *pa;
 
+	/*
+	 * XXX
+	 * We map the VGA registers, so that other driver don't
+	 * think they can.  This stops vga@isa or pcdisplay@isa
+	 * attaching, and stealing wsdisplay0.  Yuck.
+	 */
+	sc->sc_temp_set = bus_space_map(pa->pa_memt, 0xb0000, 0x10000, 0,
+					&sc->sc_temp_memh);
+
 	config_mountroot(self, &radeon_attach_real);
 }
 
@@ -180,6 +192,13 @@ radeon_attach_real(device_t self)
 	ok = radeon_pci_lookup(pa, &flags);
 	KASSERT(ok);
 
+	/*
+	 * XXX
+	 * Unmap the VGA registers so the DRM code can map them.
+	 */
+	if (sc->sc_temp_set)
+		bus_space_unmap(pa->pa_memt, sc->sc_temp_memh, 0x10000);
+
 	sc->sc_task_state = RADEON_TASK_ATTACH;
 	SIMPLEQ_INIT(&sc->sc_task_u.attach);