drm/msm/dpu: Set possible clones for all encoders

Set writeback encoders as possible clones for DSI encoders and vice
versa.

Reviewed-by: Dmitry Baryshkov <[email protected]>
Reviewed-by: Abhinav Kumar <[email protected]>
Signed-off-by: Jessica Zhang <[email protected]>
Patchwork: https://patchwork.freedesktop.org/patch/637498/
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Dmitry Baryshkov <[email protected]>

Author: Jessica Zhang

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c

@@ -2569,6 +2569,38 @@ static int dpu_encoder_virt_add_phys_encs(
 	return 0;
 }
 
+/**
+ * dpu_encoder_get_clones - Calculate the possible_clones for DPU encoder
+ * @drm_enc:        DRM encoder pointer
+ * Returns:         possible_clones mask
+ */
+uint32_t dpu_encoder_get_clones(struct drm_encoder *drm_enc)
+{
+	struct drm_encoder *curr;
+	int type = drm_enc->encoder_type;
+	uint32_t clone_mask = drm_encoder_mask(drm_enc);
+
+	/*
+	 * Set writeback as possible clones of real-time DSI encoders and vice
+	 * versa
+	 *
+	 * Writeback encoders can't be clones of each other and DSI
+	 * encoders can't be clones of each other.
+	 *
+	 * TODO: Add DP encoders as valid possible clones for writeback encoders
+	 * (and vice versa) once concurrent writeback has been validated for DP
+	 */
+	drm_for_each_encoder(curr, drm_enc->dev) {
+		if ((type == DRM_MODE_ENCODER_VIRTUAL &&
+		    curr->encoder_type == DRM_MODE_ENCODER_DSI) ||
+		    (type == DRM_MODE_ENCODER_DSI &&
+		    curr->encoder_type == DRM_MODE_ENCODER_VIRTUAL))
+			clone_mask |= drm_encoder_mask(curr);
+	}
+
+	return clone_mask;
+}
+
 static int dpu_encoder_setup_display(struct dpu_encoder_virt *dpu_enc,
 				 struct dpu_kms *dpu_kms,
 				 struct msm_display_info *disp_info)

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h

@@ -60,6 +60,8 @@ enum dpu_intf_mode dpu_encoder_get_intf_mode(struct drm_encoder *encoder);
 
 void dpu_encoder_virt_runtime_resume(struct drm_encoder *encoder);
 
+uint32_t dpu_encoder_get_clones(struct drm_encoder *drm_enc);
+
 struct drm_encoder *dpu_encoder_init(struct drm_device *dev,
 		int drm_enc_mode,
 		struct msm_display_info *disp_info);

drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c

@@ -2,7 +2,7 @@
 /*
  * Copyright (C) 2013 Red Hat
  * Copyright (c) 2014-2018, The Linux Foundation. All rights reserved.
- * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All rights reserved.
  *
  * Author: Rob Clark <[email protected]>
  */
@@ -824,8 +824,11 @@ static int _dpu_kms_drm_obj_init(struct dpu_kms *dpu_kms)
 		return ret;
 
 	num_encoders = 0;
-	drm_for_each_encoder(encoder, dev)
+	drm_for_each_encoder(encoder, dev) {
 		num_encoders++;
+		if (catalog->cwb_count > 0)
+			encoder->possible_clones = dpu_encoder_get_clones(encoder);
+	}
 
 	max_crtc_count = min(catalog->mixer_count, num_encoders);