diff options
Diffstat (limited to 'drivers/gpu/drm/drm_edid.c')
-rw-r--r-- | drivers/gpu/drm/drm_edid.c | 76 |
1 files changed, 69 insertions, 7 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index bbc25e3b7220..4005dab6147d 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -5165,6 +5165,51 @@ static void fixup_detailed_cea_mode_clock(struct drm_display_mode *mode) mode->clock = clock; } +static void drm_calculate_luminance_range(struct drm_connector *connector) +{ + struct hdr_static_metadata *hdr_metadata = &connector->hdr_sink_metadata.hdmi_type1; + struct drm_luminance_range_info *luminance_range = + &connector->display_info.luminance_range; + static const u8 pre_computed_values[] = { + 50, 51, 52, 53, 55, 56, 57, 58, 59, 61, 62, 63, 65, 66, 68, 69, + 71, 72, 74, 75, 77, 79, 81, 82, 84, 86, 88, 90, 92, 94, 96, 98 + }; + u32 max_avg, min_cll, max, min, q, r; + + if (!(hdr_metadata->metadata_type & BIT(HDMI_STATIC_METADATA_TYPE1))) + return; + + max_avg = hdr_metadata->max_fall; + min_cll = hdr_metadata->min_cll; + + /* + * From the specification (CTA-861-G), for calculating the maximum + * luminance we need to use: + * Luminance = 50*2**(CV/32) + * Where CV is a one-byte value. + * For calculating this expression we may need float point precision; + * to avoid this complexity level, we take advantage that CV is divided + * by a constant. From the Euclids division algorithm, we know that CV + * can be written as: CV = 32*q + r. Next, we replace CV in the + * Luminance expression and get 50*(2**q)*(2**(r/32)), hence we just + * need to pre-compute the value of r/32. For pre-computing the values + * We just used the following Ruby line: + * (0...32).each {|cv| puts (50*2**(cv/32.0)).round} + * The results of the above expressions can be verified at + * pre_computed_values. + */ + q = max_avg >> 5; + r = max_avg % 32; + max = (1 << q) * pre_computed_values[r]; + + /* min luminance: maxLum * (CV/255)^2 / 100 */ + q = DIV_ROUND_CLOSEST(min_cll, 255); + min = max * DIV_ROUND_CLOSEST((q * q), 100); + + luminance_range->min_luminance = min; + luminance_range->max_luminance = max; +} + static uint8_t eotf_supported(const u8 *edid_ext) { return edid_ext[2] & @@ -5196,8 +5241,12 @@ drm_parse_hdr_metadata_block(struct drm_connector *connector, const u8 *db) connector->hdr_sink_metadata.hdmi_type1.max_cll = db[4]; if (len >= 5) connector->hdr_sink_metadata.hdmi_type1.max_fall = db[5]; - if (len >= 6) + if (len >= 6) { connector->hdr_sink_metadata.hdmi_type1.min_cll = db[6]; + + /* Calculate only when all values are available */ + drm_calculate_luminance_range(connector); + } } static void @@ -5971,12 +6020,14 @@ static void drm_parse_cea_ext(struct drm_connector *connector, } static -void get_monitor_range(const struct detailed_timing *timing, - void *info_monitor_range) +void get_monitor_range(const struct detailed_timing *timing, void *c) { - struct drm_monitor_range_info *monitor_range = info_monitor_range; + struct detailed_mode_closure *closure = c; + struct drm_display_info *info = &closure->connector->display_info; + struct drm_monitor_range_info *monitor_range = &info->monitor_range; const struct detailed_non_pixel *data = &timing->data.other_data; const struct detailed_data_monitor_range *range = &data->data.range; + const struct edid *edid = closure->drm_edid->edid; if (!is_display_descriptor(timing, EDID_DETAIL_MONITOR_RANGE)) return; @@ -5992,18 +6043,28 @@ void get_monitor_range(const struct detailed_timing *timing, monitor_range->min_vfreq = range->min_vfreq; monitor_range->max_vfreq = range->max_vfreq; + + if (edid->revision >= 4) { + if (data->pad2 & DRM_EDID_RANGE_OFFSET_MIN_VFREQ) + monitor_range->min_vfreq += 255; + if (data->pad2 & DRM_EDID_RANGE_OFFSET_MAX_VFREQ) + monitor_range->max_vfreq += 255; + } } static void drm_get_monitor_range(struct drm_connector *connector, const struct drm_edid *drm_edid) { - struct drm_display_info *info = &connector->display_info; + const struct drm_display_info *info = &connector->display_info; + struct detailed_mode_closure closure = { + .connector = connector, + .drm_edid = drm_edid, + }; if (!version_greater(drm_edid, 1, 1)) return; - drm_for_each_detailed_block(drm_edid, get_monitor_range, - &info->monitor_range); + drm_for_each_detailed_block(drm_edid, get_monitor_range, &closure); DRM_DEBUG_KMS("Supported Monitor Refresh rate range is %d Hz - %d Hz\n", info->monitor_range.min_vfreq, @@ -6101,6 +6162,7 @@ static void drm_reset_display_info(struct drm_connector *connector) info->non_desktop = 0; memset(&info->monitor_range, 0, sizeof(info->monitor_range)); + memset(&info->luminance_range, 0, sizeof(info->luminance_range)); info->mso_stream_count = 0; info->mso_pixel_overlap = 0; |