Thanks, Jani. This is the issue ticket. https://gitlab.freedesktop.org/drm/intel/-/issues/6087#note_1400843 Regards William -----Original Message----- From: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Sent: Tuesday, May 31, 2022 7:07 PM To: Tseng, William <william.tseng@xxxxxxxxx>; dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: Lee, Shawn C <shawn.c.lee@xxxxxxxxx>; Wayne Lin <waynelin@xxxxxxx>; Tseng, William <william.tseng@xxxxxxxxx> Subject: Re: [PATCH] drm/edid: ignore the CEA modes not defined in CEA-861-D On Tue, 31 May 2022, Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> wrote: > On Tue, 31 May 2022, William Tseng <william.tseng@xxxxxxxxx> 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@xxxxxxxxxxxxxxx> >> Cc: Wayne Lin <waynelin@xxxxxxx> >> Cc: Lee Shawn C <shawn.c.lee@xxxxxxxxx> >> Signed-off-by: William Tseng <william.tseng@xxxxxxxxx> >> --- >> 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) { -- Jani Nikula, Intel Open Source Graphics Center
