Index: radeon_bios.c
===================================================================
RCS file: /cvsroot/src/sys/external/bsd/drm2/dist/drm/radeon/radeon_bios.c,v
retrieving revision 1.2
diff -u -w -r1.2 radeon_bios.c
--- radeon_bios.c	16 Jul 2014 20:59:57 -0000	1.2
+++ radeon_bios.c	18 Aug 2014 21:11:04 -0000
@@ -135,8 +135,35 @@
 
 static bool radeon_read_platform_bios(struct radeon_device *rdev)
 {
-#ifdef __NetBSD__		/* XXX radeon platform bios */
+#ifdef __NetBSD__		/* XXX this is x86 bollocks */
+#if defined(__i386__) || defined(__x86_64__)
+	bus_space_handle_t romh;
+
+	/* look for a legacy video BIOS at c000:0000 */
+	if (bus_space_map(rdev->pdev->pd_pa.pa_memt, 0xc0000, 0x10000,
+	    BUS_SPACE_MAP_LINEAR | BUS_SPACE_MAP_PREFETCHABLE, &romh) != 0) {
+		aprint_error("%s: unable to map legacy ROM\n", __func__);
+		return false;
+	}
+	if ((bus_space_read_1(rdev->pdev->pd_pa.pa_memt, romh, 0) !=0x55) ||
+	    (bus_space_read_1(rdev->pdev->pd_pa.pa_memt, romh, 1) !=0xaa)) {
+		aprint_error("%s: not a valid video BIOS at 0xc0000\n", __func__);
+		goto fail;
+	}
+	rdev->bios = kmalloc(0x10000, GFP_KERNEL);
+	if (rdev->bios == NULL) {
+		aprint_error("%s: couldn't allocate memory for BIOS\n", __func__);
+		goto fail;
+	}
+	bus_space_read_region_1(rdev->pdev->pd_pa.pa_memt, romh, 0, rdev->bios, 0x10000);
+	bus_space_unmap(rdev->pdev->pd_pa.pa_memt, romh, 0x10000);
+	return true;
+fail:
+	bus_space_unmap(rdev->pdev->pd_pa.pa_memt, romh, 0x10000);
+	return false;
+#else /* !x86 */
 	return false;
+#endif
 #else
 	uint8_t __iomem *bios;
 	size_t size;