drm/msm/dpu: Configure CWB in writeback encoder

Cache the CWB block mask in the DPU virtual encoder and configure CWB
according to the CWB block mask within the writeback phys encoder

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/637501/
Link: https://lore.kernel.org/r/20250214-concurrent-wb-v6-8-a44c293cf422@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

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

@@ -24,6 +24,7 @@
 #include "dpu_hw_catalog.h"
 #include "dpu_hw_intf.h"
 #include "dpu_hw_ctl.h"
+#include "dpu_hw_cwb.h"
 #include "dpu_hw_dspp.h"
 #include "dpu_hw_dsc.h"
 #include "dpu_hw_merge3d.h"
@@ -139,6 +140,7 @@ enum dpu_enc_rc_states {
  *			num_phys_encs.
  * @hw_dsc:		Handle to the DSC blocks used for the display.
  * @dsc_mask:		Bitmask of used DSC blocks.
+ * @cwb_mask		Bitmask of used CWB muxes
  * @intfs_swapped:	Whether or not the phys_enc interfaces have been swapped
  *			for partial update right-only cases, such as pingpong
  *			split where virtual pingpong does not generate IRQs
@@ -185,6 +187,7 @@ struct dpu_encoder_virt {
 	struct dpu_hw_dsc *hw_dsc[MAX_CHANNELS_PER_ENC];
 
 	unsigned int dsc_mask;
+	unsigned int cwb_mask;
 
 	bool intfs_swapped;
 
@@ -1159,6 +1162,7 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 	int num_cwb = 0;
 	bool is_cwb_encoder;
 	unsigned int dsc_mask = 0;
+	unsigned int cwb_mask = 0;
 	int i;
 
 	if (!drm_enc) {
@@ -1199,8 +1203,12 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 						       ARRAY_SIZE(hw_pp));
 	}
 
-	for (i = 0; i < num_cwb; i++)
+	for (i = 0; i < num_cwb; i++) {
 		dpu_enc->hw_cwb[i] = to_dpu_hw_cwb(hw_cwb[i]);
+		cwb_mask |= BIT(dpu_enc->hw_cwb[i]->idx - CWB_0);
+	}
+
+	dpu_enc->cwb_mask = cwb_mask;
 
 	num_ctl = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
 		drm_enc->crtc, DPU_HW_BLK_CTL, hw_ctl, ARRAY_SIZE(hw_ctl));
@@ -2237,6 +2245,9 @@ void dpu_encoder_helper_phys_cleanup(struct dpu_encoder_phys *phys_enc)
 	if (phys_enc->hw_pp && phys_enc->hw_pp->ops.setup_dither)
 		phys_enc->hw_pp->ops.setup_dither(phys_enc->hw_pp, NULL);
 
+	if (dpu_enc->cwb_mask)
+		dpu_encoder_helper_phys_setup_cwb(phys_enc, false);
+
 	/* reset the merge 3D HW block */
 	if (phys_enc->hw_pp && phys_enc->hw_pp->merge_3d) {
 		phys_enc->hw_pp->merge_3d->ops.setup_3d_mode(phys_enc->hw_pp->merge_3d,
@@ -2280,6 +2291,56 @@ void dpu_encoder_helper_phys_cleanup(struct dpu_encoder_phys *phys_enc)
 	ctl->ops.clear_pending_flush(ctl);
 }
 
+void dpu_encoder_helper_phys_setup_cwb(struct dpu_encoder_phys *phys_enc,
+				       bool enable)
+{
+	struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(phys_enc->parent);
+	struct dpu_hw_cwb *hw_cwb;
+	struct dpu_hw_cwb_setup_cfg cwb_cfg;
+
+	struct dpu_kms *dpu_kms;
+	struct dpu_global_state *global_state;
+	struct dpu_hw_blk *rt_pp_list[MAX_CHANNELS_PER_ENC];
+	int num_pp;
+
+	if (!phys_enc->hw_wb)
+		return;
+
+	dpu_kms = phys_enc->dpu_kms;
+	global_state = dpu_kms_get_existing_global_state(dpu_kms);
+	num_pp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
+					       phys_enc->parent->crtc,
+					       DPU_HW_BLK_PINGPONG, rt_pp_list,
+					       ARRAY_SIZE(rt_pp_list));
+
+	if (num_pp == 0 || num_pp > MAX_CHANNELS_PER_ENC) {
+		DPU_DEBUG_ENC(dpu_enc, "invalid num_pp %d\n", num_pp);
+		return;
+	}
+
+	/*
+	 * The CWB mux supports using LM or DSPP as tap points. For now,
+	 * always use LM tap point
+	 */
+	cwb_cfg.input = INPUT_MODE_LM_OUT;
+
+	for (int i = 0; i < MAX_CHANNELS_PER_ENC; i++) {
+		hw_cwb = dpu_enc->hw_cwb[i];
+		if (!hw_cwb)
+			continue;
+
+		if (enable) {
+			struct dpu_hw_pingpong *hw_pp =
+					to_dpu_hw_pingpong(rt_pp_list[i]);
+			cwb_cfg.pp_idx = hw_pp->idx;
+		} else {
+			cwb_cfg.pp_idx = PINGPONG_NONE;
+		}
+
+		hw_cwb->ops.config_cwb(hw_cwb, &cwb_cfg);
+	}
+}
+
 /**
  * dpu_encoder_helper_phys_setup_cdm - setup chroma down sampling block
  * @phys_enc: Pointer to physical encoder
@@ -2740,6 +2801,18 @@ enum dpu_intf_mode dpu_encoder_get_intf_mode(struct drm_encoder *encoder)
 	return INTF_MODE_NONE;
 }
 
+/**
+ * dpu_encoder_helper_get_cwb_mask - get CWB blocks mask for the DPU encoder
+ * @phys_enc: Pointer to physical encoder structure
+ */
+unsigned int dpu_encoder_helper_get_cwb_mask(struct dpu_encoder_phys *phys_enc)
+{
+	struct drm_encoder *encoder = phys_enc->parent;
+	struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(encoder);
+
+	return dpu_enc->cwb_mask;
+}
+
 /**
  * dpu_encoder_helper_get_dsc - get DSC blocks mask for the DPU encoder
  *   This helper function is used by physical encoder to get DSC blocks mask

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

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
- * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2015-2018 The Linux Foundation. All rights reserved.
  */
 
@@ -309,6 +309,8 @@ static inline enum dpu_3d_blend_mode dpu_encoder_helper_get_3d_blend_mode(
 	return BLEND_3D_NONE;
 }
 
+unsigned int dpu_encoder_helper_get_cwb_mask(struct dpu_encoder_phys *phys_enc);
+
 unsigned int dpu_encoder_helper_get_dsc(struct dpu_encoder_phys *phys_enc);
 
 struct drm_dsc_config *dpu_encoder_get_dsc_config(struct drm_encoder *drm_enc);
@@ -331,6 +333,9 @@ int dpu_encoder_helper_wait_for_irq(struct dpu_encoder_phys *phys_enc,
 
 void dpu_encoder_helper_phys_cleanup(struct dpu_encoder_phys *phys_enc);
 
+void dpu_encoder_helper_phys_setup_cwb(struct dpu_encoder_phys *phys_enc,
+				       bool enable);
+
 void dpu_encoder_helper_phys_setup_cdm(struct dpu_encoder_phys *phys_enc,
 				       const struct msm_format *dpu_fmt,
 				       u32 output_type);

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

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
 #define pr_fmt(fmt)	"[drm:%s:%d] " fmt, __func__, __LINE__
@@ -340,6 +340,8 @@ static void dpu_encoder_phys_wb_setup(
 
 	dpu_encoder_helper_phys_setup_cdm(phys_enc, format, CDM_CDWN_OUTPUT_WB);
 
+	dpu_encoder_helper_phys_setup_cwb(phys_enc, true);
+
 	dpu_encoder_phys_wb_setup_ctl(phys_enc);
 }