On Tue, 31 May 2022, Jani Nikula jani.nikula@linux.intel.com wrote:
On Tue, 31 May 2022, William Tseng william.tseng@intel.com wrote:
This is a workaround for HDMI 1.4 sink which has a CEA mode with higher vic than what is defined in CEA-861-D.
As an example, a HDMI 1.4 sink has the video format 2560x1080p to be displayed and the video format is indicated by both SVD (with vic 90 and pictuure aspect ratio 64:27) and DTD. When connecting to such sink, source can't output the video format in SVD because an error is returned by drm_hdmi_avi_infoframe_from_display_mode(), which can't fill the infoframe with pictuure aspect ratio 64:27 and the vic, which is originally 90 and is changed to 0 by drm_mode_cea_vic().
To work around it, this patch ignores such CEA modes in do_cea_modes() so the modes won't be processed in drm_hdmi_avi_infoframe_from_display_mode(). And only the video format in DTD can be dispalyed.
I think we should also have a bug filed on this, with the offending EDID attached for posterity.
BR, Jani.
Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Wayne Lin waynelin@amd.com Cc: Lee Shawn C shawn.c.lee@intel.com Signed-off-by: William Tseng william.tseng@intel.com
drivers/gpu/drm/drm_edid.c | 39 +++++++++++++++++++++++++------------- 1 file changed, 26 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index bc43e1b32092..a93f68878bfd 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -3982,6 +3982,19 @@ drm_display_mode_from_cea_vic(struct drm_device *dev, } EXPORT_SYMBOL(drm_display_mode_from_cea_vic);
+static bool is_hdmi2_sink(const struct drm_connector *connector) +{
- /*
* FIXME: sil-sii8620 doesn't have a connector around when* we need one, so we have to be prepared for a NULL connector.*/- if (!connector)
return true;- return connector->display_info.hdmi.scdc.supported ||
connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR420;+}
static int do_cea_modes(struct drm_connector *connector, const u8 *db, u8 len) { @@ -3993,6 +4006,19 @@ do_cea_modes(struct drm_connector *connector, const u8 *db, u8 len)
mode = drm_display_mode_from_vic_index(connector, db, len, i); if (mode) {
u8 vic = svd_to_vic(db[i]);if (!drm_valid_cea_vic(vic))continue;drm_display_mode_from_vic_index() returns NULL in this case.
/** HDMI 1.4 VIC range: 1 <= VIC <= 64 (CEA-861-D) but* HDMI 2.0 VIC range: 1 <= VIC <= 107 (CEA-861-F). So we* have to make sure we dont break HDMI 1.4 sinks.*/if (!is_hdmi2_sink(connector) && vic > 64)continue;I'll need to double check if this is the right thing to do... but I guess the question becomes if this shouldn't be within drm_display_mode_from_vic_index().
Duplicating the condition from drm_mode_cea_vic() is probably not a good idea.
The continues in both above branches leak the mode.
BR, Jani.
/* * YCBCR420 capability block contains a bitmap which * gives the index of CEA modes from CEA VDB, which@@ -5846,19 +5872,6 @@ void drm_set_preferred_mode(struct drm_connector *connector, } EXPORT_SYMBOL(drm_set_preferred_mode);
-static bool is_hdmi2_sink(const struct drm_connector *connector) -{
- /*
* FIXME: sil-sii8620 doesn't have a connector around when* we need one, so we have to be prepared for a NULL connector.*/- if (!connector)
return true;- return connector->display_info.hdmi.scdc.supported ||
connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR420;-}
static u8 drm_mode_hdmi_vic(const struct drm_connector *connector, const struct drm_display_mode *mode) {