Re: [PATCH 06/45] drm/msm/dp: remove dp_display's dp_mode and use dp_panel's instead

[Dmitry Baryshkov]

On Thu, Dec 05, 2024 at 08:31:37PM -0800, Abhinav Kumar wrote:
> dp_display caches the current display mode and then passes it onto
> the panel to be used for programming the panel params. Remove this
> two level passing and directly populated the panel's dp_display_mode
> instead.

Remove both and use the one from crtc_state?

> 
> Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
> ---
>  drivers/gpu/drm/msm/dp/dp_display.c | 46 ++++++++++++++++---------------------
>  1 file changed, 20 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index 052db80c6a365f53c2c0a37d3b69ea2b627aea1f..4bd85ae754429333aa423c985368344cd03c7752 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -90,7 +90,6 @@ struct msm_dp_display_private {
>  	struct msm_dp_panel   *panel;
>  	struct msm_dp_ctrl    *ctrl;
>  
> -	struct msm_dp_display_mode msm_dp_mode;
>  	struct msm_dp msm_dp_display;
>  
>  	/* wait for audio signaling */
> @@ -1436,10 +1435,13 @@ bool msm_dp_needs_periph_flush(const struct msm_dp *msm_dp_display,
>  bool msm_dp_wide_bus_available(const struct msm_dp *msm_dp_display)
>  {
>  	struct msm_dp_display_private *dp;
> +	struct msm_dp_panel *dp_panel;
>  
>  	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
>  
> -	if (dp->msm_dp_mode.out_fmt_is_yuv_420)
> +	dp_panel = dp->panel;
> +
> +	if (dp_panel->msm_dp_mode.out_fmt_is_yuv_420)
>  		return false;
>  
>  	return dp->wide_bus_supported;
> @@ -1501,10 +1503,6 @@ void msm_dp_bridge_atomic_enable(struct drm_bridge *drm_bridge,
>  	bool force_link_train = false;
>  
>  	msm_dp_display = container_of(dp, struct msm_dp_display_private, msm_dp_display);
> -	if (!msm_dp_display->msm_dp_mode.drm_mode.clock) {
> -		DRM_ERROR("invalid params\n");
> -		return;
> -	}
>  
>  	if (dp->is_edp)
>  		msm_dp_hpd_plug_handle(msm_dp_display, 0);
> @@ -1516,13 +1514,6 @@ void msm_dp_bridge_atomic_enable(struct drm_bridge *drm_bridge,
>  		return;
>  	}
>  
> -	rc = msm_dp_display_set_mode(dp, &msm_dp_display->msm_dp_mode);
> -	if (rc) {
> -		DRM_ERROR("Failed to perform a mode set, rc=%d\n", rc);
> -		mutex_unlock(&msm_dp_display->event_mutex);
> -		return;
> -	}
> -
>  	state =  msm_dp_display->hpd_state;
>  
>  	if (state == ST_CONNECTED && !dp->power_on) {
> @@ -1599,37 +1590,40 @@ void msm_dp_bridge_mode_set(struct drm_bridge *drm_bridge,
>  	struct msm_dp *dp = msm_dp_bridge->msm_dp_display;
>  	struct msm_dp_display_private *msm_dp_display;
>  	struct msm_dp_panel *msm_dp_panel;
> +	struct msm_dp_display_mode msm_dp_mode;

No need to allocate it on stack just to copy it later on. Please write
the data directly to a proper location from the beginning.

>  
>  	msm_dp_display = container_of(dp, struct msm_dp_display_private, msm_dp_display);
>  	msm_dp_panel = msm_dp_display->panel;
>  
> -	memset(&msm_dp_display->msm_dp_mode, 0x0, sizeof(struct msm_dp_display_mode));
> +	memset(&msm_dp_mode, 0x0, sizeof(struct msm_dp_display_mode));
>  
>  	if (msm_dp_display_check_video_test(dp))
> -		msm_dp_display->msm_dp_mode.bpp = msm_dp_display_get_test_bpp(dp);
> +		msm_dp_mode.bpp = msm_dp_display_get_test_bpp(dp);
>  	else /* Default num_components per pixel = 3 */
> -		msm_dp_display->msm_dp_mode.bpp = dp->connector->display_info.bpc * 3;
> +		msm_dp_mode.bpp = dp->connector->display_info.bpc * 3;
>  
> -	if (!msm_dp_display->msm_dp_mode.bpp)
> -		msm_dp_display->msm_dp_mode.bpp = 24; /* Default bpp */
> +	if (!msm_dp_mode.bpp)
> +		msm_dp_mode.bpp = 24; /* Default bpp */

The msm_dp_mode.bpp gets rewritten by msm_dp_panel_init_panel_info()
after being set here. Is this code part redundant?

>  
> -	drm_mode_copy(&msm_dp_display->msm_dp_mode.drm_mode, adjusted_mode);
> +	drm_mode_copy(&msm_dp_mode.drm_mode, adjusted_mode);
>  
> -	msm_dp_display->msm_dp_mode.v_active_low =
> -		!!(msm_dp_display->msm_dp_mode.drm_mode.flags & DRM_MODE_FLAG_NVSYNC);
> +	msm_dp_mode.v_active_low =
> +		!!(msm_dp_mode.drm_mode.flags & DRM_MODE_FLAG_NVSYNC);
>  
> -	msm_dp_display->msm_dp_mode.h_active_low =
> -		!!(msm_dp_display->msm_dp_mode.drm_mode.flags & DRM_MODE_FLAG_NHSYNC);
> +	msm_dp_mode.h_active_low =
> +		!!(msm_dp_mode.drm_mode.flags & DRM_MODE_FLAG_NHSYNC);
>  
> -	msm_dp_display->msm_dp_mode.out_fmt_is_yuv_420 =
> +	msm_dp_mode.out_fmt_is_yuv_420 =
>  		drm_mode_is_420_only(&dp->connector->display_info, adjusted_mode) &&
>  		msm_dp_panel->vsc_sdp_supported;
>  
> +	msm_dp_display_set_mode(dp, &msm_dp_mode);
> +
>  	/* populate wide_bus_support to different layers */
>  	msm_dp_display->ctrl->wide_bus_en =
> -		msm_dp_display->msm_dp_mode.out_fmt_is_yuv_420 ? false : msm_dp_display->wide_bus_supported;
> +		msm_dp_panel->msm_dp_mode.out_fmt_is_yuv_420 ? false : msm_dp_display->wide_bus_supported;
>  	msm_dp_display->catalog->wide_bus_en =
> -		msm_dp_display->msm_dp_mode.out_fmt_is_yuv_420 ? false : msm_dp_display->wide_bus_supported;
> +		msm_dp_panel->msm_dp_mode.out_fmt_is_yuv_420 ? false : msm_dp_display->wide_bus_supported;
>  }
>  
>  void msm_dp_bridge_hpd_enable(struct drm_bridge *bridge)
> 
> -- 
> 2.34.1
> 

-- 
With best wishes
Dmitry