[PATCH 4/6] drm/komeda: Add side by side support for writeback

[james qian wang (Arm Technology China)]

In side by side mode, the master pipeline writeback the left frame and the
slave writeback the right part, the data flow as below:

  slave.compiz -> slave.wb_layer -> fb (right-part)
  master.compiz -> master.wb_layer -> fb (left-part)

Signed-off-by: James Qian Wang (Arm Technology China) <james.qian.wang at arm.com>
---
 .../drm/arm/display/komeda/komeda_pipeline.h  |  4 ++
 .../display/komeda/komeda_pipeline_state.c    | 42 +++++++++++++++++++
 .../arm/display/komeda/komeda_wb_connector.c  |  6 ++-
 3 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.h b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.h
index 3358bcea8f7d..9145af3355f4 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.h
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.h
@@ -554,6 +554,10 @@ int komeda_build_wb_split_data_flow(struct komeda_layer *wb_layer,
 				    struct drm_connector_state *conn_st,
 				    struct komeda_crtc_state *kcrtc_st,
 				    struct komeda_data_flow_cfg *dflow);
+int komeda_build_wb_sbs_data_flow(struct komeda_crtc *kcrtc,
+				  struct drm_connector_state *conn_st,
+				  struct komeda_crtc_state *kcrtc_st,
+				  struct komeda_data_flow_cfg *wb_dflow);

 int komeda_build_display_data_flow(struct komeda_crtc *kcrtc,
 				   struct komeda_crtc_state *kcrtc_st);
diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c
index 4e5c891fbbd4..9fcd3d7cabe5 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c
@@ -1349,6 +1349,48 @@ int komeda_build_wb_split_data_flow(struct komeda_layer *wb_layer,
 	return komeda_wb_layer_validate(wb_layer, conn_st, dflow);
 }

+/* writeback side by side split data path:
+ *
+ * slave.compiz -> slave.wb_layer - > fb (right-part)
+ * master.compiz -> master.wb_layer -> fb (left-part)
+ */
+int komeda_build_wb_sbs_data_flow(struct komeda_crtc *kcrtc,
+				  struct drm_connector_state *conn_st,
+				  struct komeda_crtc_state *kcrtc_st,
+				  struct komeda_data_flow_cfg *wb_dflow)
+{
+	struct komeda_pipeline *master = kcrtc->master;
+	struct komeda_pipeline *slave = kcrtc->slave;
+	struct komeda_data_flow_cfg m_dflow, s_dflow;
+	int err;
+
+	if (wb_dflow->en_scaling || wb_dflow->en_img_enhancement) {
+		DRM_DEBUG_ATOMIC("sbs doesn't support WB_scaling\n");
+		return -EINVAL;
+	}
+
+	memcpy(&m_dflow, wb_dflow, sizeof(*wb_dflow));
+	memcpy(&s_dflow, wb_dflow, sizeof(*wb_dflow));
+
+	/* master writeout the left part */
+	m_dflow.in_w >>= 1;
+	m_dflow.out_w >>= 1;
+	m_dflow.input.component = &master->compiz->base;
+
+	/* slave writeout the right part */
+	s_dflow.in_w >>= 1;
+	s_dflow.out_w >>= 1;
+	s_dflow.in_x += m_dflow.in_w;
+	s_dflow.out_x += m_dflow.out_w;
+	s_dflow.input.component = &slave->compiz->base;
+
+	err = komeda_wb_layer_validate(master->wb_layer, conn_st, &m_dflow);
+	if (err)
+		return err;
+
+	return komeda_wb_layer_validate(slave->wb_layer, conn_st, &s_dflow);
+}
+
 /* build display output data flow, the data path is:
  * compiz -> improc -> timing_ctrlr
  */
diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c b/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c
index c1b0ad22422e..ea584b1e5bd2 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c
@@ -45,6 +45,7 @@ komeda_wb_encoder_atomic_check(struct drm_encoder *encoder,
 			       struct drm_crtc_state *crtc_st,
 			       struct drm_connector_state *conn_st)
 {
+	struct komeda_crtc *kcrtc = to_kcrtc(crtc_st->crtc);
 	struct komeda_crtc_state *kcrtc_st = to_kcrtc_st(crtc_st);
 	struct drm_writeback_job *writeback_job = conn_st->writeback_job;
 	struct komeda_layer *wb_layer;
@@ -73,7 +74,10 @@ komeda_wb_encoder_atomic_check(struct drm_encoder *encoder,
 	if (err)
 		return err;

-	if (dflow.en_split)
+	if (kcrtc->side_by_side)
+		err = komeda_build_wb_sbs_data_flow(kcrtc,
+				conn_st, kcrtc_st, &dflow);
+	else if (dflow.en_split)
 		err = komeda_build_wb_split_data_flow(wb_layer,
 				conn_st, kcrtc_st, &dflow);
 	else
--
2.20.1