diff mbox series

[14/21] drm/msm/dpu: Reserve resources for CWB

Message ID 20240829-concurrent-wb-v1-14-502b16ae2ebb@quicinc.com
State New
Headers show
Series drm/msm/dpu: Add Concurrent Writeback Support for DPU 10.x+ | expand

Commit Message

Jessica Zhang Aug. 29, 2024, 8:48 p.m. UTC
Reserve dedicated pingpong blocks for CWB

Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 17 ++++++--
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h |  1 +
 drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c      | 65 +++++++++++++++++++++++++++++
 3 files changed, 79 insertions(+), 4 deletions(-)

Comments

Dmitry Baryshkov Aug. 30, 2024, 5:25 p.m. UTC | #1
On Thu, Aug 29, 2024 at 01:48:35PM GMT, Jessica Zhang wrote:
> Reserve dedicated pingpong blocks for CWB

Please explain design ideas. Having just a single phrase is usually not
enough.

> 
> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> ---
>  drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 17 ++++++--
>  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h |  1 +
>  drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c      | 65 +++++++++++++++++++++++++++++
>  3 files changed, 79 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 36b677cf9c7a..f1bd14d1f89e 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>
>   */
> @@ -1054,6 +1054,7 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
>  	struct dpu_hw_blk *hw_ctl[MAX_CHANNELS_PER_ENC];
>  	struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
>  	int num_pp, num_dsc;
> +	bool is_cwb_encoder;
>  	unsigned int dsc_mask = 0;
>  	int i;
>  
> @@ -1067,6 +1068,8 @@ 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 +1080,15 @@ 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));
> +	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));

Why is this necessary? Can we still use DPU_HW_BLK_PINGPONG?

> +
>  	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 c43cb55fe1d2..c87790a1b940 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> @@ -77,6 +77,7 @@ 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,
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> index 13f84375e15d..afad26556cd5 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> @@ -236,6 +236,48 @@ static int _dpu_rm_get_lm_peer(struct dpu_rm *rm, int primary_idx)
>  	return -EINVAL;
>  }
>  
> +static int _dpu_rm_reserve_cwb_pingpong(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_idx[MAX_BLOCKS];
> +
> +	/*
> +	 * Reserve additional dedicated CWB pingpong blocks for each mixer
> +	 *
> +	 * TODO: add support for reserving non-dedicated CWB pingpong blocks
> +	 */
> +	for (int i = 0; i < ARRAY_SIZE(rm->mixer_blks) &&
> +			cwb_pp_count < num_cwb_pp; i++) {
> +		for (int j = PINGPONG_CWB_0 - PINGPONG_0;
> +				j < ARRAY_SIZE(rm->pingpong_blks); j++) {

Alignment...

> +			/*
> +			 * 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_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;
> +
> +	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
> @@ -617,6 +659,14 @@ static int _dpu_rm_make_reservation(
>  		return ret;
>  	}
>  
> +	if (topology->cwb_enabled) {
> +		ret = _dpu_rm_reserve_cwb_pingpong(rm, global_state,
> +				crtc_id, topology);
> +		if (ret) {
> +			DPU_ERROR("unable to find appropriate dcwb pingpongs\n");
> +			return ret;
> +		}
> +	}
>  
>  	ret = _dpu_rm_reserve_ctls(rm, global_state, crtc_id,
>  			topology);
> @@ -706,6 +756,7 @@ 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);
> @@ -745,6 +796,20 @@ 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);
> 
> -- 
> 2.34.1
>
Dmitry Baryshkov Aug. 30, 2024, 10:27 p.m. UTC | #2
On Fri, 30 Aug 2024 at 23:28, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
> On 8/30/2024 10:25 AM, Dmitry Baryshkov wrote:
> > On Thu, Aug 29, 2024 at 01:48:35PM GMT, Jessica Zhang wrote:
> >> Reserve dedicated pingpong blocks for CWB
> >
> > Please explain design ideas. Having just a single phrase is usually not
> > enough.
> >
> >>
> >> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> >> ---
> >>   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 17 ++++++--
> >>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h |  1 +
> >>   drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c      | 65 +++++++++++++++++++++++++++++
> >>   3 files changed, 79 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 36b677cf9c7a..f1bd14d1f89e 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>
> >>    */
> >> @@ -1054,6 +1054,7 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
> >>      struct dpu_hw_blk *hw_ctl[MAX_CHANNELS_PER_ENC];
> >>      struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
> >>      int num_pp, num_dsc;
> >> +    bool is_cwb_encoder;
> >>      unsigned int dsc_mask = 0;
> >>      int i;
> >>
> >> @@ -1067,6 +1068,8 @@ 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 +1080,15 @@ 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));
> >> +    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));
> >
> > Why is this necessary? Can we still use DPU_HW_BLK_PINGPONG?
>
> Hi Dmitry,
>
> Since both regular non-cwb pingpongs and pingpongs dedicated for cwb
> both share the same pingpong_to_crtc_id map, I need a way to distinguish
> between the real-time and dedicated cwb pingpongs.
>
> If I don't do that, get_assigned_resources would populate the hw_pp
> array for both the real-time and WB encoders with *only* the real-time
> display pingpongs.

I see. It looks like PINGPONG blocks should be allocated / filled
per-encoder, not per-CRTC. Likewise CDM is encoder-specific, not
CRTC-specific.
Does that solve the issue?

>
> >
> >> +
> >>      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 c43cb55fe1d2..c87790a1b940 100644
> >> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> >> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> >> @@ -77,6 +77,7 @@ 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,
> >> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> >> index 13f84375e15d..afad26556cd5 100644
> >> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> >> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> >> @@ -236,6 +236,48 @@ static int _dpu_rm_get_lm_peer(struct dpu_rm *rm, int primary_idx)
> >>      return -EINVAL;
> >>   }
> >>
> >> +static int _dpu_rm_reserve_cwb_pingpong(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_idx[MAX_BLOCKS];
> >> +
> >> +    /*
> >> +     * Reserve additional dedicated CWB pingpong blocks for each mixer
> >> +     *
> >> +     * TODO: add support for reserving non-dedicated CWB pingpong blocks
> >> +     */
> >> +    for (int i = 0; i < ARRAY_SIZE(rm->mixer_blks) &&
> >> +                    cwb_pp_count < num_cwb_pp; i++) {
> >> +            for (int j = PINGPONG_CWB_0 - PINGPONG_0;
> >> +                            j < ARRAY_SIZE(rm->pingpong_blks); j++) {
> >
> > Alignment...
>
> Ack -- for future reference, should I always align the second line with
> the bracket of the previous line?
>
> I thought the general guideline was 2 tabs, but I might be misremembering.

I can't find the textual reference, however .clang-format in the root
dir has 'AlignAfterOpenBracket: Align'. I'm more or less ignorant for
the function argument alignment (especially if an old function is
being modified), but aligning the conditions and loops makes it easier
to read the code.

>
> Thanks,
>
> Jessica Zhang
>
> >
> >> +                    /*
> >> +                     * 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_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;
> >> +
> >> +    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
> >> @@ -617,6 +659,14 @@ static int _dpu_rm_make_reservation(
> >>              return ret;
> >>      }
> >>
> >> +    if (topology->cwb_enabled) {
> >> +            ret = _dpu_rm_reserve_cwb_pingpong(rm, global_state,
> >> +                            crtc_id, topology);
> >> +            if (ret) {
> >> +                    DPU_ERROR("unable to find appropriate dcwb pingpongs\n");
> >> +                    return ret;
> >> +            }
> >> +    }
> >>
> >>      ret = _dpu_rm_reserve_ctls(rm, global_state, crtc_id,
> >>                      topology);
> >> @@ -706,6 +756,7 @@ 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);
> >> @@ -745,6 +796,20 @@ 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);
> >>
> >> --
> >> 2.34.1
> >>
> >
> > --
> > With best wishes
> > Dmitry
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 36b677cf9c7a..f1bd14d1f89e 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>
  */
@@ -1054,6 +1054,7 @@  static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 	struct dpu_hw_blk *hw_ctl[MAX_CHANNELS_PER_ENC];
 	struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
 	int num_pp, num_dsc;
+	bool is_cwb_encoder;
 	unsigned int dsc_mask = 0;
 	int i;
 
@@ -1067,6 +1068,8 @@  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 +1080,15 @@  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));
+	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));
+
 	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 c43cb55fe1d2..c87790a1b940 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
@@ -77,6 +77,7 @@  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,
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
index 13f84375e15d..afad26556cd5 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
@@ -236,6 +236,48 @@  static int _dpu_rm_get_lm_peer(struct dpu_rm *rm, int primary_idx)
 	return -EINVAL;
 }
 
+static int _dpu_rm_reserve_cwb_pingpong(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_idx[MAX_BLOCKS];
+
+	/*
+	 * Reserve additional dedicated CWB pingpong blocks for each mixer
+	 *
+	 * TODO: add support for reserving non-dedicated CWB pingpong blocks
+	 */
+	for (int i = 0; i < ARRAY_SIZE(rm->mixer_blks) &&
+			cwb_pp_count < num_cwb_pp; i++) {
+		for (int j = PINGPONG_CWB_0 - PINGPONG_0;
+				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_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;
+
+	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
@@ -617,6 +659,14 @@  static int _dpu_rm_make_reservation(
 		return ret;
 	}
 
+	if (topology->cwb_enabled) {
+		ret = _dpu_rm_reserve_cwb_pingpong(rm, global_state,
+				crtc_id, topology);
+		if (ret) {
+			DPU_ERROR("unable to find appropriate dcwb pingpongs\n");
+			return ret;
+		}
+	}
 
 	ret = _dpu_rm_reserve_ctls(rm, global_state, crtc_id,
 			topology);
@@ -706,6 +756,7 @@  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);
@@ -745,6 +796,20 @@  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);