On Thu, 29 Aug 2024 at 13:20, Jun Nie <jun.nie@xxxxxxxxxx> wrote:
>
> request more mixer for the case that hdisplay exceeding 4096
> and DSC enabled.
This doesn't seem to match the code. And it misses the _reason_ to do it.
>
> Signed-off-by: Jun Nie <jun.nie@xxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 24 ++++++++++++++++++++----
> 1 file changed, 20 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 05b203be2a9bc..33cfd94badaba 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> @@ -59,6 +59,7 @@
> #define IDLE_SHORT_TIMEOUT 1
>
> #define MAX_HDISPLAY_SPLIT 1080
> +#define MAX_HDISPLAY_DSC_SPLIT 2560
>
> /* timeout in frames waiting for frame done */
> #define DPU_ENCODER_FRAME_DONE_TIMEOUT_FRAMES 5
> @@ -588,15 +589,19 @@ static struct msm_display_topology dpu_encoder_get_topology(
>
> /* Datapath topology selection
> *
> - * Dual display
> + * Dual display without DSC
> * 2 LM, 2 INTF ( Split display using 2 interfaces)
> *
> + * Dual display with DSC
> + * 4 LM, 2 INTF ( Split display using 2 interfaces)
This doesn't match the code
> + *
> * Single display
> * 1 LM, 1 INTF
> * 2 LM, 1 INTF (stream merge to support high resolution interfaces)
> *
> * Add dspps to the reservation requirements if ctm is requested
> */
> +
> if (intf_count == 2)
> topology.num_lm = 2;
> else if (!dpu_kms->catalog->caps->has_3d_merge)
> @@ -615,10 +620,21 @@ static struct msm_display_topology dpu_encoder_get_topology(
> * 2 DSC encoders, 2 layer mixers and 1 interface
> * this is power optimal and can drive up to (including) 4k
> * screens
> + * But for dual display with hdisplay exceeding 4096, we need
> + * 4 layer mixer. Because DSC has a max width of 2048 and
> + * a single plane can only be used by one mixer pair
> */
> - topology.num_dsc = 2;
> - topology.num_lm = 2;
> - topology.num_intf = 1;
> +
> + if (intf_count == 2 &&
> + mode->hdisplay > MAX_HDISPLAY_DSC_SPLIT) {
> + topology.num_dsc = 4;
> + topology.num_lm = 4;
> + topology.num_intf = 2;
> + } else {
> + topology.num_dsc = 2;
> + topology.num_lm = 2;
> + topology.num_intf = 1;
> + }
> }
>
> return topology;
>
> --
> 2.34.1
>
--
With best wishes
Dmitry
