Merge tag 'drm-misc-next-2022-08-20-1' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for v6.1:

UAPI Changes:

Cross-subsystem Changes:
- DMA-buf: documentation updates.
- Assorted small fixes to vga16fb
- Fix fbdev drivers to use the aperture helpers.
- Make removal of conflicting drivers work correctly without fbdev enabled.

Core Changes:
- bridge, scheduler, dp-mst: Assorted small fixes.
- Add more format helpers to fourcc, and use it to replace the cpp usage.
- Add DRM_FORMAT_Cxx, DRM_FORMAT_Rxx (single channel), and DRM_FORMAT_Dxx
  ("darkness", inverted single channel)
- Add packed AYUV8888 and XYUV8888 formats.
- Assorted documentation updates.
- Rename ttm_bo_init to ttm_bo_init_validate.
- Allow TTM bo's to exist without backing store.
- Convert drm selftests to kunit.
- Add managed init functions for (panel) bridge, crtc, encoder and connector.
- Fix endianness handling in various format conversion helpers.
- Make tests pass on big-endian platforms, and add test for rgb888 -> rgb565
- Move DRM_PLANE_HELPER_NO_SCALING to atomic helpers and rename, so
  drm_plane_helper is no longer needed in most drivers.
- Use idr_init_base instead of idr_init.
- Rename FB and GEM CMA helpers to DMA helpers.
- Rework XRGB8888 related conversion helpers, and add drm_fb_blit() that
  takes a iosys_map. Make drm_fb_memcpy take an iosys_map too.
- Move edid luminance calculation to core, and use it in i915.

Driver Changes:
- bridge/{adv7511,ti-sn65dsi86,parade-ps8640}, panel/{simple,nt35510,tc358767},
  nouveau, sun4i, mipi-dsi, mgag200, bochs, arm, komeda, vmwgfx, pl111:
  Assorted small fixes and doc updates.
- vc4: Rework hdmi power up, and depend on PM.
- panel/simple: Add Samsung LTL101AL01.
- ingenic: Add JZ4760(B) support, avoid a modeset when sharpness property
  is unchanged, and use the new PM ops.
- Revert some amdgpu commits that cause garbaged graphics when starting
  X, and reapply them with the real problem fixed.
- Completely rework vc4 init to use managed helpers.
- Rename via_drv to via_dri1, and move all stuff there only used by the
  dri1 implementation in preperation for atomic modeset.
- Use regmap bulk write in ssd130x.
- Power sequence and clock updates to it6505.
- Split panel-sitrox-st7701  init sequence and rework mode programming code.
- virtio: Improve error and edge conditions handling, and convert to use managed
  helpers.
- Add Samsung LTL101AL01, B120XAN01.0, R140NWF5 RH, DMT028VGHMCMI-1A T, panels.
- Add generic fbdev support to komeda.
- Split mgag200 modeset handling to make it more model-specific.
- Convert simpledrm to use atomic helpers.
- Improve udl suspend/disconnect handling.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f0c71766-61e8-19b7-763a-5fbcdefc633d@linux.intel.com

1 files changed, 51 insertions, 1 deletions

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index bbc25e3b7220..90a5e26eafa8 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
@@ -6101,6 +6150,7 @@ 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;