drm/i915: Extract physical display dimensions from VBT

The VBT has these mysterious H/V image sizes as part of the display
timings. Looking at some dumps those appear to be the physical
dimensions in mm. Which makes sense since the timing descriptor matches
the format used by EDID detailed timing descriptor, which defines these
as "H/V Addressable Video Image Size in mm".

So let's use that information from the panel fixed mode to get the
physical dimensions for LVDS/eDP/DSI displays. And with that we can
fill out the display_info so that userspace can get at it via
GetConnector.

v2: Use (hi<<8)|lo instead of broken (hi<<4)+lo
    Handle LVDS and eDP too

Cc: Stephen Just <stephenjust@gmail.com>
Tested-by: Stephen Just <stephenjust@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96255
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1464685714-30507-1-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
(cherry picked from commit df457245b5b7515cf97763ebd8975229e34d4cf3)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

5 files changed, 18 insertions, 4 deletions

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 5198185..b9022fa 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -139,6 +139,11 @@ fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
 	else
 		panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;
 
+	panel_fixed_mode->width_mm = (dvo_timing->himage_hi << 8) |
+		dvo_timing->himage_lo;
+	panel_fixed_mode->height_mm = (dvo_timing->vimage_hi << 8) |
+		dvo_timing->vimage_lo;
+
 	/* Some VBTs have bogus h/vtotal values */
 	if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
 		panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 2991326..ffe5f84 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -5725,8 +5725,11 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 	if (!fixed_mode && dev_priv->vbt.lfp_lvds_vbt_mode) {
 		fixed_mode = drm_mode_duplicate(dev,
 					dev_priv->vbt.lfp_lvds_vbt_mode);
-		if (fixed_mode)
+		if (fixed_mode) {
 			fixed_mode->type |= DRM_MODE_TYPE_PREFERRED;
+			connector->display_info.width_mm = fixed_mode->width_mm;
+			connector->display_info.height_mm = fixed_mode->height_mm;
+		}
 	}
 	mutex_unlock(&dev->mode_config.mutex);
 
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 366ad6c..4756ef6 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -1545,6 +1545,9 @@ void intel_dsi_init(struct drm_device *dev)
 		goto err;
 	}
 
+	connector->display_info.width_mm = fixed_mode->width_mm;
+	connector->display_info.height_mm = fixed_mode->height_mm;
+
 	intel_panel_init(&intel_connector->panel, fixed_mode, NULL);
 
 	intel_dsi_add_properties(intel_connector);
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index bc53c0d..96281e6 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -1082,6 +1082,8 @@ void intel_lvds_init(struct drm_device *dev)
 		fixed_mode = drm_mode_duplicate(dev, dev_priv->vbt.lfp_lvds_vbt_mode);
 		if (fixed_mode) {
 			fixed_mode->type |= DRM_MODE_TYPE_PREFERRED;
+			connector->display_info.width_mm = fixed_mode->width_mm;
+			connector->display_info.height_mm = fixed_mode->height_mm;
 			goto out;
 		}
 	}
diff --git a/drivers/gpu/drm/i915/intel_vbt_defs.h b/drivers/gpu/drm/i915/intel_vbt_defs.h
index c15051d..44fb0b3 100644
--- a/drivers/gpu/drm/i915/intel_vbt_defs.h
+++ b/drivers/gpu/drm/i915/intel_vbt_defs.h
@@ -403,9 +403,10 @@ struct lvds_dvo_timing {
 	u8 vsync_off:4;
 	u8 rsvd0:6;
 	u8 hsync_off_hi:2;
-	u8 h_image;
-	u8 v_image;
-	u8 max_hv;
+	u8 himage_lo;
+	u8 vimage_lo;
+	u8 vimage_hi:4;
+	u8 himage_hi:4;
 	u8 h_border;
 	u8 v_border;
 	u8 rsvd1:3;