drm/i915: Assign hwmode after encoder state readout

The dotclock is often calculated in encoder .get_config(), so we
shouldn't copy the adjusted_mode to hwmode until we have read out the
dotclock.

Gets rid of some warnings like these:
[drm:drm_calc_timestamping_constants [drm]] *ERROR* crtc 21: Can't calculate constants, dotclock = 0!
[drm:i915_get_vblank_timestamp] crtc 0 is disabled

v2: Steal Maarten's idea to move crtc->mode etc. assignment too

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91428
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[Jani: cherry-picked from -next to v4.3]
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

1 files changed, 30 insertions, 27 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7704315e067f..ed87a7e4c32a 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -15132,33 +15132,6 @@ static void intel_modeset_readout_hw_state(struct drm_device *dev)
                 crtc->base.state->active = crtc->active;
                 crtc->base.enabled = crtc->active;
 
-                memset(&crtc->base.mode, 0, sizeof(crtc->base.mode));
-                if (crtc->base.state->active) {
-                        intel_mode_from_pipe_config(&crtc->base.mode, crtc->config);
-                        intel_mode_from_pipe_config(&crtc->base.state->adjusted_mode, crtc->config);
-                        WARN_ON(drm_atomic_set_mode_for_crtc(crtc->base.state, &crtc->base.mode));
-
-                        /*
-                         * The initial mode needs to be set in order to keep
-                         * the atomic core happy. It wants a valid mode if the
-                         * crtc's enabled, so we do the above call.
-                         *
-                         * At this point some state updated by the connectors
-                         * in their ->detect() callback has not run yet, so
-                         * no recalculation can be done yet.
-                         *
-                         * Even if we could do a recalculation and modeset
-                         * right now it would cause a double modeset if
-                         * fbdev or userspace chooses a different initial mode.
-                         *
-                         * If that happens, someone indicated they wanted a
-                         * mode change, which means it's safe to do a full
-                         * recalculation.
-                         */
-                        crtc->base.state->mode.private_flags = I915_MODE_FLAG_INHERITED;
-                }
-
-                crtc->base.hwmode = crtc->config->base.adjusted_mode;
                 readout_plane_state(crtc, to_intel_crtc_state(crtc->base.state));
 
                 DRM_DEBUG_KMS("[CRTC:%d] hw state readout: %s\n",
@@ -15218,6 +15191,36 @@ static void intel_modeset_readout_hw_state(struct drm_device *dev)
                               connector->base.name,
                               connector->base.encoder ? "enabled" : "disabled");
         }
+
+        for_each_intel_crtc(dev, crtc) {
+                crtc->base.hwmode = crtc->config->base.adjusted_mode;
+
+                memset(&crtc->base.mode, 0, sizeof(crtc->base.mode));
+                if (crtc->base.state->active) {
+                        intel_mode_from_pipe_config(&crtc->base.mode, crtc->config);
+                        intel_mode_from_pipe_config(&crtc->base.state->adjusted_mode, crtc->config);
+                        WARN_ON(drm_atomic_set_mode_for_crtc(crtc->base.state, &crtc->base.mode));
+
+                        /*
+                         * The initial mode needs to be set in order to keep
+                         * the atomic core happy. It wants a valid mode if the
+                         * crtc's enabled, so we do the above call.
+                         *
+                         * At this point some state updated by the connectors
+                         * in their ->detect() callback has not run yet, so
+                         * no recalculation can be done yet.
+                         *
+                         * Even if we could do a recalculation and modeset
+                         * right now it would cause a double modeset if
+                         * fbdev or userspace chooses a different initial mode.
+                         *
+                         * If that happens, someone indicated they wanted a
+                         * mode change, which means it's safe to do a full
+                         * recalculation.
+                         */
+                        crtc->base.state->mode.private_flags = I915_MODE_FLAG_INHERITED;
+                }
+        }
 }
 
 /* Scan out the current hw modeset state,