If we aren't changing the power state, no need to take locks and schedule fences, etc.
There seem to be lock ordering issues in the CP and fence code in some cases; see bug 29140 below. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=29140 Possibly also: https://bugzilla.kernel.org/show_bug.cgi?id=16581 Signed-off-by: Alex Deucher <alexdeucher at gmail.com> Cc: stable at kernel.org --- drivers/gpu/drm/radeon/radeon_pm.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c index a3d25f4..9a8031b 100644 --- a/drivers/gpu/drm/radeon/radeon_pm.c +++ b/drivers/gpu/drm/radeon/radeon_pm.c @@ -226,6 +226,11 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev) { int i; + /* no need to take locks, etc. if nothing's going to change */ + if ((rdev->pm.requested_clock_mode_index == rdev->pm.current_clock_mode_index) && + (rdev->pm.requested_power_state_index == rdev->pm.current_power_state_index)) + return; + mutex_lock(&rdev->ddev->struct_mutex); mutex_lock(&rdev->vram_mutex); mutex_lock(&rdev->cp.mutex); -- 1.7.1.1
