On Mon, Dec 16, 2024 at 04:43:26PM -0800, Jessica Zhang wrote:
> Add the cwb_enabled flag to msm_display topology and adjust the toplogy
> to account for concurrent writeback
Why?
>
> Signed-off-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 11 ++++++++++-
> drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c | 10 ++++++++--
> drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h | 2 ++
> 3 files changed, 20 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> index b4bfded3d53025853cee112ca598533ece290318..b063c8fe4c0594772d84401fa56c9c21afc0ad18 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> @@ -1198,6 +1198,8 @@ static struct msm_display_topology dpu_crtc_get_topology(
> dpu_encoder_update_topology(drm_enc, &topology, crtc_state->state,
> &crtc_state->adjusted_mode);
>
> + topology.cwb_enabled = drm_crtc_in_clone_mode(crtc_state);
> +
> /*
> * Datapath topology selection
> *
> @@ -1209,9 +1211,16 @@ static struct msm_display_topology dpu_crtc_get_topology(
> * 2 LM, 1 INTF (stream merge to support high resolution interfaces)
> *
> * Add dspps to the reservation requirements if ctm is requested
> + *
> + * Only hardcode num_lm to 2 for cases where num_intf == 2 and CWB is not
> + * enabled. This is because in cases where CWB is enabled, num_intf will
> + * count both the WB and real-time phys encoders.
> + *
> + * For non-DSC CWB usecases, have the num_lm be decided by the
> + * (mode->hdisplay > MAX_HDISPLAY_SPLIT) check.
> */
>
> - if (topology.num_intf == 2)
> + if (topology.num_intf == 2 && !topology.cwb_enabled)
> topology.num_lm = 2;
> else if (topology.num_dsc == 2)
> topology.num_lm = 2;
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> index b763ef19f4c60ae8a35df6a6ffb19e8411bc63f8..85adaf256b2c705d2d7df378b6ffc0e578f52bc3 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> @@ -382,8 +382,14 @@ static int _dpu_rm_reserve_ctls(
> int i = 0, j, num_ctls;
> bool needs_split_display;
>
> - /* each hw_intf needs its own hw_ctrl to program its control path */
> - num_ctls = top->num_intf;
> + /*
> + * For non-CWB mode, each hw_intf needs its own hw_ctl to program its
> + * control path. Hardcode num_ctls to 1 if CWB is enabled
> + */
Why?
> + if (top->cwb_enabled)
> + num_ctls = 1;
> + else
> + num_ctls = top->num_intf;
>
> needs_split_display = _dpu_rm_needs_split_display(top);
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
> index b061dfdab52e04ab7d777e912a30173273cb3db7..12db21a2403ec6930894c36a58e898c5d94c2568 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
> @@ -46,6 +46,7 @@ struct dpu_rm {
> * @num_dspp: number of dspp blocks used
> * @num_dsc: number of Display Stream Compression (DSC) blocks used
> * @needs_cdm: indicates whether cdm block is needed for this display topology
> + * @cwb_enabled: indicates whether CWB is enabled for this display topology
> */
> struct msm_display_topology {
> u32 num_lm;
> @@ -53,6 +54,7 @@ struct msm_display_topology {
> u32 num_dspp;
> u32 num_dsc;
> bool needs_cdm;
> + bool cwb_enabled;
> };
>
> int dpu_rm_init(struct drm_device *dev,
>
> --
> 2.34.1
>
--
With best wishes
Dmitry
