fbmem, drm/nouveau: kick firmware framebuffers as soon as possible

Currently vesafb/efifb/... is kicked when hardware driver is registering
framebuffer. To do it hardware must be fully functional, so there's a short
window between start of initialisation and framebuffer registration when
two drivers touch the hardware. Unfortunately sometimes it breaks nouveau
initialisation.

Fix it by kicking firmware driver(s) before we start touching the hardware.

Reported-by: Didier Spaier <didier.spaier@epsm.fr>
Tested-by: Didier Spaier <didier.spaier@epsm.fr>
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 25 insertions, 18 deletions

diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index 03f2dc2..7cfcd71 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c
@@ -1479,11 +1479,10 @@ static bool apertures_overlap(struct aperture *gen, struct aperture *hw)
 	return false;
 }
 
-static bool fb_do_apertures_overlap(struct fb_info *gen, struct fb_info *hw)
+static bool fb_do_apertures_overlap(struct apertures_struct *gena,
+				    struct apertures_struct *hwa)
 {
 	int i, j;
-	struct apertures_struct *hwa = hw->apertures;
-	struct apertures_struct *gena = gen->apertures;
 	if (!hwa || !gena)
 		return false;
 
@@ -1501,6 +1500,28 @@ static bool fb_do_apertures_overlap(struct fb_info *gen, struct fb_info *hw)
 	return false;
 }
 
+void remove_conflicting_framebuffers(struct apertures_struct *a, const char *name)
+{
+	int i;
+
+	/* check all firmware fbs and kick off if the base addr overlaps */
+	for (i = 0 ; i < FB_MAX; i++) {
+		if (!registered_fb[i])
+			continue;
+
+		if (!(registered_fb[i]->flags & FBINFO_MISC_FIRMWARE))
+			continue;
+
+		if (fb_do_apertures_overlap(registered_fb[i]->apertures, a)) {
+			printk(KERN_ERR "fb: conflicting fb hw usage "
+			       "%s vs %s - removing generic driver\n",
+			       name, registered_fb[i]->fix.id);
+			unregister_framebuffer(registered_fb[i]);
+		}
+	}
+}
+EXPORT_SYMBOL(remove_conflicting_framebuffers);
+
 /**
  *	register_framebuffer - registers a frame buffer device
  *	@fb_info: frame buffer info structure
@@ -1524,21 +1545,7 @@ register_framebuffer(struct fb_info *fb_info)
 	if (fb_check_foreignness(fb_info))
 		return -ENOSYS;
 
-	/* check all firmware fbs and kick off if the base addr overlaps */
-	for (i = 0 ; i < FB_MAX; i++) {
-		if (!registered_fb[i])
-			continue;
-
-		if (registered_fb[i]->flags & FBINFO_MISC_FIRMWARE) {
-			if (fb_do_apertures_overlap(registered_fb[i], fb_info)) {
-				printk(KERN_ERR "fb: conflicting fb hw usage "
-				       "%s vs %s - removing generic driver\n",
-				       fb_info->fix.id,
-				       registered_fb[i]->fix.id);
-				unregister_framebuffer(registered_fb[i]);
-			}
-		}
-	}
+	remove_conflicting_framebuffers(fb_info->apertures, fb_info->fix.id);
 
 	num_registered_fb++;
 	for (i = 0 ; i < FB_MAX; i++)