[PATCH v3] drm/dp: Add function to parse EDID descriptors for adaptive sync limits

[Manasi Navare]

On Tue, Mar 03, 2020 at 03:42:12PM +0200, Ville Syrjälä wrote:
> On Mon, Mar 02, 2020 at 04:08:59PM -0800, Manasi Navare wrote:
> > Adaptive Sync is a VESA feature so add a DRM core helper to parse
> > the EDID's detailed descritors to obtain the adaptive sync monitor range.
> > Store this info as part fo drm_display_info so it can be used
> > across all drivers.
> > This part of the code is stripped out of amdgpu's function
> > amdgpu_dm_update_freesync_caps() to make it generic and be used
> > across all DRM drivers
> > 
> > v3:
> > * Remove the edid parsing restriction for just DP (Nicholas)
> > * Use drm_for_each_detailed_block (Ville)
> > * Make the drm_get_adaptive_sync_range function static (Harry, Jani)
> > v2:
> > * Change vmin and vmax to use u8 (Ville)
> > * Dont store pixel clock since that is just a max dotclock
> > and not related to VRR mode (Manasi)
> > 
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Cc: Harry Wentland <harry.wentland at amd.com>
> > Cc: Clinton A Taylor <clinton.a.taylor at intel.com>
> > Cc: Kazlauskas, Nicholas <Nicholas.Kazlauskas at amd.com>
> > Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
> > ---
> >  drivers/gpu/drm/drm_edid.c  | 44 +++++++++++++++++++++++++++++++++++++
> >  include/drm/drm_connector.h | 22 +++++++++++++++++++
> >  2 files changed, 66 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> > index ad41764a4ebe..e3f152180b6b 100644
> > --- a/drivers/gpu/drm/drm_edid.c
> > +++ b/drivers/gpu/drm/drm_edid.c
> > @@ -4938,6 +4938,47 @@ static void drm_parse_cea_ext(struct drm_connector *connector,
> >  	}
> >  }
> >  
> > +static
> > +void get_adaptive_sync_range(struct detailed_timing *timing,
> > +			     void *info_adaptive_sync)
> > +{
> > +	struct drm_adaptive_sync_info *adaptive_sync = info_adaptive_sync;
> > +	const struct detailed_non_pixel *data = &timing->data.other_data;
> > +	const struct detailed_data_monitor_range *range = &data->data.range;
> > +
> > +	if (data->type != EDID_DETAIL_MONITOR_RANGE)a
> 
> is_display_descriptor()

Will change to use is_display_descriptor()

> 
> > +		return;
> > +
> > +	/*
> > +	 * Check for flag range limits only. If flag == 1 then
> > +	 * no additional timing information provided.
> > +	 * Default GTF, GTF Secondary curve and CVT are not
> > +	 * supported
> > +	 */
> > +	if (range->flags != 1)
> 
> Pls name the flags.

I dont see that we have any enum with the flag names, do you want me to define them looking
at EDID spec?

Manasi

> 
> > +		return;
> > +
> > +	adaptive_sync->min_vfreq = range->min_vfreq;
> > +	adaptive_sync->max_vfreq = range->max_vfreq;
> > +}
> > +
> > +static
> > +void drm_get_adaptive_sync_range(struct drm_connector *connector,
> > +				 const struct edid *edid)
> > +{
> > +	struct drm_display_info *info = &connector->display_info;
> > +
> > +	if (!version_greater(edid, 1, 1))
> > +		return;
> > +
> > +	drm_for_each_detailed_block((u8 *)edid, get_adaptive_sync_range,
> > +				    &info->adaptive_sync);
> > +
> > +	DRM_DEBUG_KMS("Adaptive Sync refresh rate range is %d Hz - %d Hz\n",
> > +		      info->adaptive_sync.min_vfreq,
> > +		      info->adaptive_sync.max_vfreq);
> > +}
> > +
> >  /* A connector has no EDID information, so we've got no EDID to compute quirks from. Reset
> >   * all of the values which would have been set from EDID
> >   */
> > @@ -4960,6 +5001,7 @@ drm_reset_display_info(struct drm_connector *connector)
> >  	memset(&info->hdmi, 0, sizeof(info->hdmi));
> >  
> >  	info->non_desktop = 0;
> > +	memset(&info->adaptive_sync, 0, sizeof(info->adaptive_sync));
> >  }
> >  
> >  u32 drm_add_display_info(struct drm_connector *connector, const struct edid *edid)
> > @@ -4975,6 +5017,8 @@ u32 drm_add_display_info(struct drm_connector *connector, const struct edid *edi
> >  
> >  	info->non_desktop = !!(quirks & EDID_QUIRK_NON_DESKTOP);
> >  
> > +	drm_get_adaptive_sync_range(connector, edid);
> > +
> >  	DRM_DEBUG_KMS("non_desktop set to %d\n", info->non_desktop);
> >  
> >  	if (edid->revision < 3)
> > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> > index 0df7a95ca5d9..2b22c0fa42c4 100644
> > --- a/include/drm/drm_connector.h
> > +++ b/include/drm/drm_connector.h
> > @@ -254,6 +254,23 @@ enum drm_panel_orientation {
> >  	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
> >  };
> >  
> > +/**
> > + * struct drm_adaptive_sync_info - Panel's Adaptive Sync capabilities for
> > + * &drm_display_info
> > + *
> > + * This struct is used to store a Panel's Adaptive Sync capabilities
> > + * as parsed from EDID's detailed monitor range descriptor block.
> > + *
> > + * @min_vfreq: This is the min supported refresh rate in Hz from
> > + *             EDID's detailed monitor range.
> > + * @max_vfreq: This is the max supported refresh rate in Hz from
> > + *             EDID's detailed monitor range
> > + */
> > +struct drm_adaptive_sync_info {
> > +	u8 min_vfreq;
> > +	u8 max_vfreq;
> > +};
> > +
> >  /*
> >   * This is a consolidated colorimetry list supported by HDMI and
> >   * DP protocol standard. The respective connectors will register
> > @@ -473,6 +490,11 @@ struct drm_display_info {
> >  	 * @non_desktop: Non desktop display (HMD).
> >  	 */
> >  	bool non_desktop;
> > +
> > +	/**
> > +	 * @adaptive_sync: Adaptive Sync capabilities of the DP/eDP sink
> > +	 */
> > +	struct drm_adaptive_sync_info adaptive_sync;
> >  };
> >  
> >  int drm_display_info_set_bus_formats(struct drm_display_info *info,
> > -- 
> > 2.19.1
> 
> -- 
> Ville Syrjälä
> Intel
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel