drm/tegra: dc: Implement runtime PM

Use runtime PM to clock-gate, assert reset and powergate the display
controller. This ties in nicely with atomic DPMS in that a runtime PM
reference is taken before a pipe is enabled and dropped after it has
been shut down.

To make sure this works, make sure to only ever update planes on active
CRTCs, otherwise register accesses to a clock-gated and reset CRTC will
hang the CPU.

Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index b59c3bf0df44..f753e239c55d 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -56,8 +56,8 @@ static void tegra_atomic_complete(struct tegra_drm *tegra,
          */
 
         drm_atomic_helper_commit_modeset_disables(drm, state);
-        drm_atomic_helper_commit_planes(drm, state, false);
         drm_atomic_helper_commit_modeset_enables(drm, state);
+        drm_atomic_helper_commit_planes(drm, state, true);
 
         drm_atomic_helper_wait_for_vblanks(drm, state);