drm/msm/dpu: don't set crtc_state->mode_changed from atomic_check()

The MSM driver uses drm_atomic_helper_check() which mandates that none
of the atomic_check() callbacks toggles crtc_state->mode_changed.
Perform corresponding check before calling the drm_atomic_helper_check()
function.

Fixes: 8b45a26f2ba9 ("drm/msm/dpu: reserve cdm blocks for writeback in case of YUV output")
Reported-by: Simona Vetter <simona.vetter@ffwll.ch>
Closes: https://lore.kernel.org/dri-devel/ZtW_S0j5AEr4g0QW@phenom.ffwll.local/
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
[DB: dropped the WARN_ON]
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/633400/
Link: https://lore.kernel.org/r/20250123-drm-dirty-modeset-v2-4-bbfd3a6cd1a4@linaro.org

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 32992e9525530ea4dec2f46643fc06d40d3bca7b..1fc220a2ce0d9850a714a906a7b25425ace14a5e 100644 (file)
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -760,6 +760,34 @@ static void dpu_encoder_assign_crtc_resources(struct dpu_kms *dpu_kms,
        cstate->num_mixers = num_lm;
 }
 
+/**
+ * dpu_encoder_virt_check_mode_changed: check if full modeset is required
+ * @drm_enc:    Pointer to drm encoder structure
+ * @crtc_state:        Corresponding CRTC state to be checked
+ * @conn_state: Corresponding Connector's state to be checked
+ *
+ * Check if the changes in the object properties demand full mode set.
+ */
+int dpu_encoder_virt_check_mode_changed(struct drm_encoder *drm_enc,
+                                       struct drm_crtc_state *crtc_state,
+                                       struct drm_connector_state *conn_state)
+{
+       struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(drm_enc);
+       struct msm_display_topology topology;
+
+       DPU_DEBUG_ENC(dpu_enc, "\n");
+
+       /* Using mode instead of adjusted_mode as it wasn't computed yet */
+       topology = dpu_encoder_get_topology(dpu_enc, &crtc_state->mode, crtc_state, conn_state);
+
+       if (topology.needs_cdm && !dpu_enc->cur_master->hw_cdm)
+               crtc_state->mode_changed = true;
+       else if (!topology.needs_cdm && dpu_enc->cur_master->hw_cdm)
+               crtc_state->mode_changed = true;
+
+       return 0;
+}
+
 static int dpu_encoder_virt_atomic_check(
                struct drm_encoder *drm_enc,
                struct drm_crtc_state *crtc_state,
@@ -793,10 +821,6 @@ static int dpu_encoder_virt_atomic_check(
 
        topology = dpu_encoder_get_topology(dpu_enc, adj_mode, crtc_state, conn_state);
 
-       if (topology.needs_cdm && !dpu_enc->cur_master->hw_cdm)
-               crtc_state->mode_changed = true;
-       else if (!topology.needs_cdm && dpu_enc->cur_master->hw_cdm)
-               crtc_state->mode_changed = true;
        /*
         * Release and Allocate resources on every modeset
         */

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
index 92b5ee390788d16e85e195a664417896a2bf1cae..da133ee4701a329f566f6f9a7255f2f6d050f891 100644 (file)
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
@@ -88,4 +88,8 @@ void dpu_encoder_cleanup_wb_job(struct drm_encoder *drm_enc,
 
 bool dpu_encoder_is_valid_for_commit(struct drm_encoder *drm_enc);
 
+int dpu_encoder_virt_check_mode_changed(struct drm_encoder *drm_enc,
+                                       struct drm_crtc_state *crtc_state,
+                                       struct drm_connector_state *conn_state);
+
 #endif /* __DPU_ENCODER_H__ */

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index 97e9cb8c2b099f4757169cadf7e941148d2bfb16..8741dc6fc8ddc405940fdc95072b19ad4c7f6960 100644 (file)
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -446,6 +446,29 @@ static void dpu_kms_disable_commit(struct msm_kms *kms)
        pm_runtime_put_sync(&dpu_kms->pdev->dev);
 }
 
+static int dpu_kms_check_mode_changed(struct msm_kms *kms, struct drm_atomic_state *state)
+{
+       struct drm_crtc_state *new_crtc_state;
+       struct drm_connector *connector;
+       struct drm_connector_state *new_conn_state;
+       int i;
+
+       for_each_new_connector_in_state(state, connector, new_conn_state, i) {
+               struct drm_encoder *encoder;
+
+               if (!new_conn_state->crtc || !new_conn_state->best_encoder)
+                       continue;
+
+               new_crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc);
+
+               encoder = new_conn_state->best_encoder;
+
+               dpu_encoder_virt_check_mode_changed(encoder, new_crtc_state, new_conn_state);
+       }
+
+       return 0;
+}
+
 static void dpu_kms_flush_commit(struct msm_kms *kms, unsigned crtc_mask)
 {
        struct dpu_kms *dpu_kms = to_dpu_kms(kms);
@@ -1062,6 +1085,7 @@ static const struct msm_kms_funcs kms_funcs = {
        .irq             = dpu_core_irq,
        .enable_commit   = dpu_kms_enable_commit,
        .disable_commit  = dpu_kms_disable_commit,
+       .check_mode_changed = dpu_kms_check_mode_changed,
        .flush_commit    = dpu_kms_flush_commit,
        .wait_flush      = dpu_kms_wait_flush,
        .complete_commit = dpu_kms_complete_commit,

diff --git a/drivers/gpu/drm/msm/msm_atomic.c b/drivers/gpu/drm/msm/msm_atomic.c
index 83c4e6aca20951b0f5616764f99c39cdaf524593..87a91148a731dc911f30695add4c8f5002770220 100644 (file)
--- a/drivers/gpu/drm/msm/msm_atomic.c
+++ b/drivers/gpu/drm/msm/msm_atomic.c
@@ -183,10 +183,16 @@ static unsigned get_crtc_mask(struct drm_atomic_state *state)
 
 int msm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 {
+       struct msm_drm_private *priv = dev->dev_private;
+       struct msm_kms *kms = priv->kms;
        struct drm_crtc_state *old_crtc_state, *new_crtc_state;
        struct drm_crtc *crtc;
-       int i;
+       int i, ret = 0;
 
+       /*
+        * FIXME: stop setting allow_modeset and move this check to the DPU
+        * driver.
+        */
        for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state,
                                      new_crtc_state, i) {
                if ((old_crtc_state->ctm && !new_crtc_state->ctm) ||
@@ -196,6 +202,11 @@ int msm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
                }
        }
 
+       if (kms && kms->funcs && kms->funcs->check_mode_changed)
+               ret = kms->funcs->check_mode_changed(kms, state);
+       if (ret)
+               return ret;
+
        return drm_atomic_helper_check(dev, state);
 }
 

diff --git a/drivers/gpu/drm/msm/msm_kms.h b/drivers/gpu/drm/msm/msm_kms.h
index 3e28c4e012d2be6fd5af11324e13249623431697..43b58d052ee6aae0ce34d09c88e1e1c34f9c52ef 100644 (file)
--- a/drivers/gpu/drm/msm/msm_kms.h
+++ b/drivers/gpu/drm/msm/msm_kms.h
@@ -59,6 +59,13 @@ struct msm_kms_funcs {
        void (*enable_commit)(struct msm_kms *kms);
        void (*disable_commit)(struct msm_kms *kms);
 
+       /**
+        * @check_mode_changed:
+        *
+        * Verify if the commit requires a full modeset on one of CRTCs.
+        */
+       int (*check_mode_changed)(struct msm_kms *kms, struct drm_atomic_state *state);
+
        /**
         * Prepare for atomic commit.  This is called after any previous
         * (async or otherwise) commit has completed.