On Wed, May 14, 2025 at 04:52:31PM -0700, Jessica Zhang wrote:
> Validate requested mode and topology based on the PINGPONG or DSC encoder
> max width. In addition, drop MAX_HDISPLAY_SPLIT and base LM reservation
> off of PINGPONG or DSC encoder max width
Separate commit for num_lm, please.
>
> As noted in the patch, while DPU 8.x+ supports a max linewidth of 8960
> for PINGPONG_0, there is some additional logic that needs to be added to
> the resource manager to specifically try and reserve PINGPONG_0 for
> modes that are greater than 5k.
>
> Since this is out of the scope of this series, add a helper that will
> get the overall minimum PINGPONG max linewidth for a given chipset.
>
> Signed-off-by: Jessica Zhang <jessica.zh...@oss.qualcomm.com>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 46
> +++++++++++++++++++++++++++-----
> 1 file changed, 39 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> index 0714936d8835..6131d071b051 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> @@ -723,6 +723,31 @@ void dpu_crtc_complete_commit(struct drm_crtc *crtc)
> _dpu_crtc_complete_flip(crtc);
> }
>
> +static int msm_display_get_max_pingpong_width(struct dpu_kms *dpu_kms)
> +{
> + const struct dpu_pingpong_cfg *pingpong;
> + u32 max_pingpong_width = dpu_kms->catalog->pingpong[0].max_linewidth;
> +
> + /*
> + * Find the smallest overall PINGPONG max_linewidth in the catalog since
> + * max_linewidth can differ between PINGPONGs even within the same
> + * chipset.
> + *
> + * Note: While, for DPU 8.x+, PINGPONG_0 can technically support up to
> + * 8k resolutions, this requires reworking the RM to try to reserve
> + * PINGPONG_0 for modes greater than 5k.
> + *
> + * Once this additional logic is implemented, we can drop this helper
> + * and use the reserved PINGPONG's max_linewidth
> + */
> + for (int i = 1; i < dpu_kms->catalog->pingpong_count; i++) {
> + pingpong = &dpu_kms->catalog->pingpong[i];
> + max_pingpong_width = min(max_pingpong_width,
> pingpong->max_linewidth);
> + }
Since we are skipping PINGPONG_0, wouldn't it be enough to return
max_linewidth of PP_1 ?
I think, it would be easier to follow .max_dsc_encoder_width and store
.max_pingpong_linewidth in dpu_caps (and later add special
.max_pp0_linewidth).
> +
> + return max_pingpong_width;
> +}
> +
> static int _dpu_crtc_check_and_setup_lm_bounds(struct drm_crtc *crtc,
> struct drm_crtc_state *state)
> {
--
With best wishes
Dmitry
