[src/trunk]: src/sys/dev/pci disable mmap()ing the framebuffer at offset 0 on...

[macallan <macallan%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b5659f304d95
branches:  trunk
changeset: 583363:b5659f304d95
user:      macallan <macallan%NetBSD.org@localhost>
date:      Tue Aug 02 01:32:13 2005 +0000

description:
disable mmap()ing the framebuffer at offset 0 on sparc64 because some ATI
firmware likes to put PCI memory resources into this range, notably a Rage
IIc which puts the 2nd register aperture to 0x2000.
This should allow a few graphics chips to work with XFree86 which previously
failed with something like this:
(WW) ATI:  PCI/AGP Mach64 in slot 2:5:0 could not be detected!
No devices to configure.  Configuration failed.

Thanks to Florian Stoehr for doing most of the work tracking this down.

diffstat:

 sys/dev/pci/machfb.c |  15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diffs (41 lines):

diff -r 7881d8aeed0d -r b5659f304d95 sys/dev/pci/machfb.c
--- a/sys/dev/pci/machfb.c      Mon Aug 01 23:00:15 2005 +0000
+++ b/sys/dev/pci/machfb.c      Tue Aug 02 01:32:13 2005 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: machfb.c,v 1.30 2005/07/07 18:43:47 thorpej Exp $      */
+/*     $NetBSD: machfb.c,v 1.31 2005/08/02 01:32:13 macallan Exp $     */
 
 /*
  * Copyright (c) 2002 Bang Jun-Young
@@ -33,7 +33,7 @@
 
 #include <sys/cdefs.h>
 __KERNEL_RCSID(0, 
-       "$NetBSD: machfb.c,v 1.30 2005/07/07 18:43:47 thorpej Exp $");
+       "$NetBSD: machfb.c,v 1.31 2005/08/02 01:32:13 macallan Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -1696,12 +1696,21 @@
        struct mach64_softc *sc = v;
        paddr_t pa;
        
-       /* 'regular' framebuffer mmap()ing */
+#ifndef __sparc64
+       /* 
+        *'regular' framebuffer mmap()ing 
+        * disabled on sparc64 because some ATI firmware likes to map some PCI
+        * resources to addresses that would collide with this ( like some Rage 
+        * IIc which uses 0x2000 for the 2nd register block )
+        * Other 64bit architectures might run into similar problems.
+        */
        if (offset<sc->sc_apersize) {
                pa = bus_space_mmap(sc->sc_memt, sc->sc_aperbase+offset, 0, 
                    prot, BUS_SPACE_MAP_LINEAR);
                return pa;
        }
+#endif
+
 #if 0
        /* evil hack to allow mmap()ing other devices as well */
        if ((offset > 0x80000000) && (offset <= 0xffffffff)) {