drm/radeon: make sure mode init is complete in bandwidth_update

The power management code calls into the display code for
certain things.  If certain power management sysfs attributes
are called before the driver has finished initializing all of
the hardware we can run into problems with uninitialized
modesetting state.  Add a check to make sure modesetting
init has completed to the bandwidth update callbacks to
fix this.  Can be triggered by the tlp and laptop start
up scripts depending on the timing.

bugs:
https://bugzilla.kernel.org/show_bug.cgi?id=83611
https://bugs.freedesktop.org/show_bug.cgi?id=85771

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 5f6db4629aaa..9acb1c3c005b 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -879,6 +879,9 @@ void rs600_bandwidth_update(struct radeon_device *rdev)
         u32 d1mode_priority_a_cnt, d2mode_priority_a_cnt;
         /* FIXME: implement full support */
 
+        if (!rdev->mode_info.mode_config_initialized)
+                return;
+
         radeon_update_display_priority(rdev);
 
         if (rdev->mode_info.crtcs[0]->base.enabled)