[PATCH v3 16/23] drm/msm/dpu: Reserve resources for CWB

[Jessica Zhang <quic_jesszhan@quicinc.com>]

Add support for RM to reserve dedicated CWB PINGPONGs and CWB muxes

For concurrent writeback, even-indexed CWB muxes must be assigned to
even-indexed LMs and odd-indexed CWB muxes for odd-indexed LMs. The same
even/odd rule applies for dedicated CWB PINGPONGs.

Track the CWB muxes in the global state and add a CWB-specific helper to
reserve the correct CWB muxes and dedicated PINGPONGs following the
even/odd rule.

Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 34 ++++++++++--
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h |  2 +
 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h     |  1 +
 drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c      | 83 +++++++++++++++++++++++++++++
 4 files changed, 116 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 36b677cf9c7a53fdedf79107db8958a67cdd2c95..b2f0bf4124512ff9b86c6e03b74a7338037e398f 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -2,7 +2,7 @@
 /*
  * Copyright (C) 2013 Red Hat
  * Copyright (c) 2014-2018, 2020-2021 The Linux Foundation. All rights reserved.
- * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All rights reserved.
  *
  * Author: Rob Clark <robdclark@gmail.com>
  */
@@ -28,6 +28,7 @@
 #include "dpu_hw_dsc.h"
 #include "dpu_hw_merge3d.h"
 #include "dpu_hw_cdm.h"
+#include "dpu_hw_cwb.h"
 #include "dpu_formats.h"
 #include "dpu_encoder_phys.h"
 #include "dpu_crtc.h"
@@ -133,6 +134,9 @@ enum dpu_enc_rc_states {
  * @cur_slave:		As above but for the slave encoder.
  * @hw_pp:		Handle to the pingpong blocks used for the display. No.
  *			pingpong blocks can be different than num_phys_encs.
+ * @hw_cwb:		Handle to the CWB muxes used for concurrent writeback
+ *			display. Number of CWB muxes can be different than
+ *			num_phys_encs.
  * @hw_dsc:		Handle to the DSC blocks used for the display.
  * @dsc_mask:		Bitmask of used DSC blocks.
  * @intfs_swapped:	Whether or not the phys_enc interfaces have been swapped
@@ -177,6 +181,7 @@ struct dpu_encoder_virt {
 	struct dpu_encoder_phys *cur_master;
 	struct dpu_encoder_phys *cur_slave;
 	struct dpu_hw_pingpong *hw_pp[MAX_CHANNELS_PER_ENC];
+	struct dpu_hw_cwb *hw_cwb[MAX_CHANNELS_PER_ENC];
 	struct dpu_hw_dsc *hw_dsc[MAX_CHANNELS_PER_ENC];
 
 	unsigned int dsc_mask;
@@ -1053,7 +1058,10 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 	struct dpu_hw_blk *hw_pp[MAX_CHANNELS_PER_ENC];
 	struct dpu_hw_blk *hw_ctl[MAX_CHANNELS_PER_ENC];
 	struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
+	struct dpu_hw_blk *hw_cwb[MAX_CHANNELS_PER_ENC];
 	int num_pp, num_dsc;
+	int num_cwb = 0;
+	bool is_cwb_encoder;
 	unsigned int dsc_mask = 0;
 	int i;
 
@@ -1067,6 +1075,8 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 
 	priv = drm_enc->dev->dev_private;
 	dpu_kms = to_dpu_kms(priv->kms);
+	is_cwb_encoder = drm_crtc_in_clone_mode(crtc_state) &&
+			dpu_enc->disp_info.intf_type == INTF_WB;
 
 	global_state = dpu_kms_get_existing_global_state(dpu_kms);
 	if (IS_ERR_OR_NULL(global_state)) {
@@ -1077,9 +1087,25 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 	trace_dpu_enc_mode_set(DRMID(drm_enc));
 
 	/* Query resource that have been reserved in atomic check step. */
-	num_pp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
-		drm_enc->crtc, DPU_HW_BLK_PINGPONG, hw_pp,
-		ARRAY_SIZE(hw_pp));
+	if (is_cwb_encoder) {
+		num_pp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
+						       drm_enc->crtc,
+						       DPU_HW_BLK_DCWB_PINGPONG,
+						       hw_pp, ARRAY_SIZE(hw_pp));
+		num_cwb = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
+						       drm_enc->crtc,
+						       DPU_HW_BLK_CWB,
+						       hw_cwb, ARRAY_SIZE(hw_cwb));
+	} else {
+		num_pp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
+						       drm_enc->crtc,
+						       DPU_HW_BLK_PINGPONG, hw_pp,
+						       ARRAY_SIZE(hw_pp));
+	}
+
+	for (i = 0; i < num_cwb; i++)
+		dpu_enc->hw_cwb[i] = to_dpu_hw_cwb(hw_cwb[i]);
+
 	dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
 			drm_enc->crtc, DPU_HW_BLK_CTL, hw_ctl, ARRAY_SIZE(hw_ctl));
 
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
index c43cb55fe1d22123abc49b68d91689c637921527..34195bf4e270b7e24f2b9ba299007159a430dd3f 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
@@ -77,12 +77,14 @@ enum dpu_hw_blk_type {
 	DPU_HW_BLK_LM,
 	DPU_HW_BLK_CTL,
 	DPU_HW_BLK_PINGPONG,
+	DPU_HW_BLK_DCWB_PINGPONG,
 	DPU_HW_BLK_INTF,
 	DPU_HW_BLK_WB,
 	DPU_HW_BLK_DSPP,
 	DPU_HW_BLK_MERGE_3D,
 	DPU_HW_BLK_DSC,
 	DPU_HW_BLK_CDM,
+	DPU_HW_BLK_CWB,
 	DPU_HW_BLK_MAX,
 };
 
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
index 4fdc5f9332610385b3642c6965f526c8442a226b..a078b5334dc196505dc02aa1053abd33a8cf3b8e 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
@@ -128,6 +128,7 @@ struct dpu_global_state {
 	uint32_t dspp_to_crtc_id[DSPP_MAX - DSPP_0];
 	uint32_t dsc_to_crtc_id[DSC_MAX - DSC_0];
 	uint32_t cdm_to_crtc_id;
+	uint32_t cwb_to_crtc_id[CWB_MAX - CWB_0];
 };
 
 struct dpu_global_state
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
index 04df3056d75a799ad4bdc87d6a9c97acdb990323..311651257bbd93ccdf041ffe01ace2710fe2feed 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
@@ -223,6 +223,55 @@ static int _dpu_rm_get_lm_peer(struct dpu_rm *rm, int primary_idx)
 	return -EINVAL;
 }
 
+static int _dpu_rm_reserve_cwb_mux_and_pingpongs(struct dpu_rm *rm,
+						 struct dpu_global_state *global_state,
+						 uint32_t crtc_id,
+						 struct msm_display_topology *topology)
+{
+	int num_cwb_pp = topology->num_lm, cwb_pp_count = 0;
+	int cwb_pp_start_idx = PINGPONG_CWB_0 - PINGPONG_0;
+	int cwb_pp_idx[MAX_BLOCKS];
+	int cwb_mux_idx[MAX_BLOCKS];
+
+	/*
+	 * Reserve additional dedicated CWB PINGPONG blocks and muxes for each
+	 * mixer
+	 *
+	 * TODO: add support reserving resources for platforms with no
+	 *       PINGPONG_CWB
+	 */
+	for (int i = 0; i < ARRAY_SIZE(rm->mixer_blks) &&
+	     cwb_pp_count < num_cwb_pp; i++) {
+		for (int j = cwb_pp_start_idx;
+		     j < ARRAY_SIZE(rm->pingpong_blks); j++) {
+			/*
+			 * Odd LMs must be assigned to odd PINGPONGs and even
+			 * LMs with even PINGPONGs
+			 */
+			if (reserved_by_other(global_state->pingpong_to_crtc_id, j, crtc_id) ||
+			    i % 2 != j % 2)
+				continue;
+
+			cwb_pp_idx[cwb_pp_count] = j;
+			cwb_mux_idx[cwb_pp_count] = j - cwb_pp_start_idx;
+			cwb_pp_count++;
+			break;
+		}
+	}
+
+	if (cwb_pp_count != num_cwb_pp) {
+		DPU_ERROR("Unable to reserve all CWB PINGPONGs\n");
+		return -ENAVAIL;
+	}
+
+	for (int i = 0; i < cwb_pp_count; i++) {
+		global_state->pingpong_to_crtc_id[cwb_pp_idx[i]] = crtc_id;
+		global_state->cwb_to_crtc_id[cwb_mux_idx[i]] = crtc_id;
+	}
+
+	return 0;
+}
+
 /**
  * _dpu_rm_check_lm_and_get_connected_blks - check if proposed layer mixer meets
  *	proposed use case requirements, incl. hardwired dependent blocks like
@@ -603,6 +652,12 @@ static int _dpu_rm_make_reservation(
 		return ret;
 	}
 
+	if (topology->cwb_enabled) {
+		ret = _dpu_rm_reserve_cwb_mux_and_pingpongs(rm, global_state,
+							    crtc_id, topology);
+		if (ret)
+			return ret;
+	}
 
 	ret = _dpu_rm_reserve_ctls(rm, global_state, crtc_id,
 			topology);
@@ -653,6 +708,8 @@ void dpu_rm_release(struct dpu_global_state *global_state,
 	_dpu_rm_clear_mapping(global_state->dspp_to_crtc_id,
 			ARRAY_SIZE(global_state->dspp_to_crtc_id), crtc_id);
 	_dpu_rm_clear_mapping(&global_state->cdm_to_crtc_id, 1, crtc_id);
+	_dpu_rm_clear_mapping(global_state->cwb_to_crtc_id,
+			ARRAY_SIZE(global_state->cwb_to_crtc_id), crtc_id);
 }
 
 int dpu_rm_reserve(
@@ -692,6 +749,7 @@ int dpu_rm_get_assigned_resources(struct dpu_rm *rm,
 
 	switch (type) {
 	case DPU_HW_BLK_PINGPONG:
+	case DPU_HW_BLK_DCWB_PINGPONG:
 		hw_blks = rm->pingpong_blks;
 		hw_to_crtc_id = global_state->pingpong_to_crtc_id;
 		max_blks = ARRAY_SIZE(rm->pingpong_blks);
@@ -721,6 +779,11 @@ int dpu_rm_get_assigned_resources(struct dpu_rm *rm,
 		hw_to_crtc_id = &global_state->cdm_to_crtc_id;
 		max_blks = 1;
 		break;
+	case DPU_HW_BLK_CWB:
+		hw_blks = rm->cwb_blks;
+		hw_to_crtc_id = global_state->cwb_to_crtc_id;
+		max_blks = ARRAY_SIZE(rm->cwb_blks);
+		break;
 	default:
 		DPU_ERROR("blk type %d not managed by rm\n", type);
 		return 0;
@@ -731,6 +794,20 @@ int dpu_rm_get_assigned_resources(struct dpu_rm *rm,
 		if (hw_to_crtc_id[i] != crtc_id)
 			continue;
 
+		if (type == DPU_HW_BLK_PINGPONG) {
+			struct dpu_hw_pingpong *pp = to_dpu_hw_pingpong(hw_blks[i]);
+
+			if (pp->idx >= PINGPONG_CWB_0)
+				continue;
+		}
+
+		if (type == DPU_HW_BLK_DCWB_PINGPONG) {
+			struct dpu_hw_pingpong *pp = to_dpu_hw_pingpong(hw_blks[i]);
+
+			if (pp->idx < PINGPONG_CWB_0)
+				continue;
+		}
+
 		if (num_blks == blks_size) {
 			DPU_ERROR("More than %d resources assigned to crtc %d\n",
 				  blks_size, crtc_id);
@@ -801,4 +878,10 @@ void dpu_rm_print_state(struct drm_printer *p,
 	dpu_rm_print_state_helper(p, rm->cdm_blk,
 				  global_state->cdm_to_crtc_id);
 	drm_puts(p, "\n");
+
+	drm_puts(p, "\tcwb=");
+	for (i = 0; i < ARRAY_SIZE(global_state->cwb_to_crtc_id); i++)
+		dpu_rm_print_state_helper(p, rm->cwb_blks[i],
+					  global_state->cwb_to_crtc_id[i]);
+	drm_puts(p, "\n");
 }

-- 
2.34.1