Re: [PATCH v3 2/3] drm/amd/display: Add freesync video modes based on preferred modes

[Shashank Sharma <shashank.sharma@amd.com>]

On 15/12/20 3:50 am, Aurabindo Pillai wrote:
> [Why&How]
> If experimental freesync video mode module parameter is enabled, add
> few extra display modes into the driver's mode list corresponding to common
> video frame rates. When userspace sets these modes, no modeset will be
> performed (if current mode was one of freesync modes or the base freesync mode
> based off which timings have been generated for the rest of the freesync modes)
> since these modes only differ from the base mode with front porch timing.
>
> Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
> Acked-by: Christian König <christian.koenig at amd.com>
> ---
>  .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 167 ++++++++++++++++++
>  .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h |   2 +
>  2 files changed, 169 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index e7ee2467eadb..c1ffd33e9d83 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -5174,6 +5174,59 @@ static void dm_enable_per_frame_crtc_master_sync(struct dc_state *context)
>  	set_master_stream(context->streams, context->stream_count);
>  }
>  
> +static struct drm_display_mode *
> +get_highest_refresh_rate_mode(struct amdgpu_dm_connector *aconnector,
> +			  bool use_probed_modes)
> +{
> +	struct drm_display_mode *m, *m_pref = NULL;
> +	u16 current_refresh, highest_refresh;
> +	struct list_head *list_head = use_probed_modes ?
> +						    &aconnector->base.probed_modes :
> +						    &aconnector->base.modes;
> +
> +	if (aconnector->freesync_vid_base.clock != 0)
> +		return &aconnector->freesync_vid_base;
> +
> +	/* Find the preferred mode */
> +	list_for_each_entry (m, list_head, head) {
> +		if (m->type & DRM_MODE_TYPE_PREFERRED) {
> +			m_pref = m;
> +			break;
> +		}
> +	}
> +
> +	if (!m_pref) {
> +		/* Probably an EDID with no preferred mode. Fallback to first entry */
> +		m_pref = list_first_entry_or_null(
> +			&aconnector->base.modes, struct drm_display_mode, head);
> +		if (!m_pref) {
> +			DRM_DEBUG_DRIVER("No preferred mode found in EDID\n");
> +			return NULL;
> +		}
> +	}
> +
> +	highest_refresh = drm_mode_vrefresh(m_pref);
> +
> +	/*
> +	 * Find the mode with highest refresh rate with same resolution.
> +	 * For some monitors, preferred mode is not the mode with highest
> +	 * supported refresh rate.
> +	 */
> +	list_for_each_entry (m, list_head, head) {
> +		current_refresh  = drm_mode_vrefresh(m);
> +
> +		if (m->hdisplay == m_pref->hdisplay &&
> +		    m->vdisplay == m_pref->vdisplay &&
> +		    highest_refresh < current_refresh) {
> +			highest_refresh = current_refresh;
> +			m_pref = m;
> +		}
> +	}
> +
> +	aconnector->freesync_vid_base = *m_pref;
> +	return m_pref;
> +}
> +
>  static struct dc_stream_state *
>  create_stream_for_sink(struct amdgpu_dm_connector *aconnector,
>  		       const struct drm_display_mode *drm_mode,
> @@ -6999,6 +7052,119 @@ static void amdgpu_dm_connector_ddc_get_modes(struct drm_connector *connector,
>  	}
>  }
>  
> +static bool is_duplicate_mode(struct amdgpu_dm_connector *aconnector,
> +			      struct drm_display_mode *mode)
> +{
> +	struct drm_display_mode *m;
> +
> +	list_for_each_entry (m, &aconnector->base.probed_modes, head) {
> +		if (drm_mode_equal(m, mode))
> +			return true;
> +	}
> +
> +	return false;
> +}
> +
> +static uint add_fs_modes(struct amdgpu_dm_connector *aconnector,
> +			 struct detailed_data_monitor_range *range)
> +{
> +	const struct drm_display_mode *m;
> +	struct drm_display_mode *new_mode;
> +	uint i;
> +	uint64_t target_vtotal, target_vtotal_diff;
> +	uint32_t new_modes_count = 0;
> +	uint64_t num, den;
My previous review comment about num,den, target_vtotal and target_vtotal_diff here was neither addressed nor explained.
> +
> +	/* Standard FPS values
> +	 *
> +	 * 23.976 - TV/NTSC
> +	 * 24	  - Cinema
> +	 * 25     - TV/PAL
> +	 * 29.97  - TV/NTSC
> +	 * 30     - TV/NTSC
> +	 * 48	  - Cinema HFR
> +	 * 50	  - TV/PAL
> +	 */
My previous review comment about 60 fps here was neither addressed nor explained.
> +	const uint32_t common_rates[] = { 23976, 24000, 25000, 29970, 30000,
> +					 48000, 50000, 60000, 72000, 96000 };
> +
> +	/*
> +	 * Find mode with highest refresh rate with the same resolution
> +	 * as the preferred mode. Some monitors report a preferred mode
> +	 * with lower resolution than the highest refresh rate supported.
> +	 */
> +
> +	m = get_highest_refresh_rate_mode(aconnector, true);
> +	if (!m)
> +		return 0;
> +
> +	for (i = 0; i < ARRAY_SIZE(common_rates); i++) {
> +		if (drm_mode_vrefresh(m) * 1000 < common_rates[i])
> +			continue;
> +
> +		if (common_rates[i] < range->min_vfreq * 1000)
> +			continue;
> +
> +		num = (unsigned long long)m->clock * 1000 * 1000;
> +		den = common_rates[i] * (unsigned long long)m->htotal;
> +		target_vtotal = div_u64(num, den);
> +		target_vtotal_diff = target_vtotal - m->vtotal;
> +
> +		/* Check for illegal modes */
> +		if (m->vsync_start + target_vtotal_diff < m->vdisplay ||
> +		    m->vsync_end + target_vtotal_diff < m->vsync_start ||
> +		    m->vtotal + target_vtotal_diff < m->vsync_end)
> +			continue;
> +
> +		new_mode = drm_mode_duplicate(aconnector->base.dev, m);
> +		if (!new_mode)
> +			goto out;
> +
> +		new_mode->vtotal += (u16)target_vtotal_diff;
> +		new_mode->vsync_start += (u16)target_vtotal_diff;
> +		new_mode->vsync_end += (u16)target_vtotal_diff;
> +		new_mode->type &= ~DRM_MODE_TYPE_PREFERRED;
> +		new_mode->type |= DRM_MODE_TYPE_DRIVER;
> +
> +		if (!is_duplicate_mode(aconnector, new_mode)) {
> +			drm_mode_probed_add(&aconnector->base, new_mode);
> +			new_modes_count += 1;
> +		} else
> +			drm_mode_destroy(aconnector->base.dev, new_mode);
> +	}
> + out:
> +	return new_modes_count;
> +}
> +
> +static void amdgpu_dm_connector_add_freesync_modes(struct drm_connector *connector,
> +						   struct edid *edid)
> +{
> +	uint8_t i;
> +	struct detailed_timing *timing;
> +	struct detailed_non_pixel *data;
> +	struct detailed_data_monitor_range *range;
> +	struct amdgpu_dm_connector *amdgpu_dm_connector =
> +		to_amdgpu_dm_connector(connector);
> +
> +	if (!(amdgpu_exp_freesync_vid_mode && edid))
> +		return;
> +
> +	if (edid->version == 1 && edid->revision > 1) {
> +		for (i = 0; i < 4; i++) {
> +			timing = &edid->detailed_timings[i];
> +			data = &timing->data.other_data;
> +			range = &data->data.range;
> +
> +			/* Check if monitor has continuous frequency mode */
> +			if (data->type == EDID_DETAIL_MONITOR_RANGE &&
> +			    range->max_vfreq - range->min_vfreq > 10) {
> +				amdgpu_dm_connector->num_modes += add_fs_modes(amdgpu_dm_connector, range);
> +				break;
> +			}
> +		}
> +	}
> +}
> +
>  static int amdgpu_dm_connector_get_modes(struct drm_connector *connector)
>  {
>  	struct amdgpu_dm_connector *amdgpu_dm_connector =
> @@ -7014,6 +7180,7 @@ static int amdgpu_dm_connector_get_modes(struct drm_connector *connector)
>  	} else {
>  		amdgpu_dm_connector_ddc_get_modes(connector, edid);
>  		amdgpu_dm_connector_add_common_modes(encoder, connector);
> +		amdgpu_dm_connector_add_freesync_modes(connector, edid);
>  	}
>  	amdgpu_dm_fbc_init(connector);
>  
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> index 251af783f6b1..f5a5f1ad7dba 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> @@ -413,6 +413,8 @@ struct amdgpu_dm_connector {
>  #endif
>  	bool force_yuv420_output;
>  	struct dsc_preferred_settings dsc_settings;
> +	/* Cached display modes */
> +	struct drm_display_mode freesync_vid_base;

With (or without) the missing comments addressed:

feel free to use: Reviewed-by: Shashank Sharma <shashank.sharma@amd.com>

- Shashank

>  };
>  
>  #define to_amdgpu_dm_connector(x) container_of(x, struct amdgpu_dm_connector, base)
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel