<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - [GLK] no signal - with samsung 4k TV - HDMI UHD Color (ENABLED)" href="https://bugs.freedesktop.org/show_bug.cgi?id=110496#c30">Comment # 30</a> on <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - [GLK] no signal - with samsung 4k TV - HDMI UHD Color (ENABLED)" href="https://bugs.freedesktop.org/show_bug.cgi?id=110496">bug 110496</a> from <a class="email" href="mailto:shashank.sharma@intel.com" title="shashank.sharma@intel.com <shashank.sharma@intel.com>"> shashank.sharma@intel.com</a> <pre>(In reply to sergey79 from <a href="show_bug.cgi?id=110496#c29">comment #29</a>) > (In reply to <a href="mailto:shashank.sharma@intel.com">shashank.sharma@intel.com</a> from <a href="show_bug.cgi?id=110496#c27">comment #27</a>) > > > That's why we can see 4k@30 deep color, 4k@60 YCBCR 420 deep color outputs > > working on this TV, but as soon as we switch to RGB 4k@60, the driver > > restricts the HDMI output to 4k@60 8BPC, which is being rejected by the TV, > > in the UHD mode of operation. > > 420 works only @50/60Hz, only @ 8-bit. 420 @ deep color and other refresh > rates (24/25/30) is not supported by the TV at all (with UHD Color on or > off). 4K 420 is targeted for 50/60Hz only. > > The only difference between "HDMI UHD Color" on and off is that TV sends > different EDID data. I analyzed both EDIDs - basically the only important > difference is the presence of HDMI-Forum VSDB block which enable Deep Color > in 4k modes. > The presence of HF_VSDB indicates HDMI 2.0 EDID, not deep color. Deep color can be supported in HDMI 1.4b EDIDs too if the clock supports. > 4k modes that work (UHD Color off): > RGB 24/25/30Hz 8-bit > 420 50/60Hz 8-bit > > 4k modes that don't work (UHD Color on): > RGB 24/25/30Hz 12-bit > RGB 50/60Hz 8-bit Can you also dump 420VDB and 420CMDB from the CEA-extension blocks? > > As you can see, any mode that require 594 Mhz pixel clock - does not work. > And any mode that require only 297 Mhz - works just fine. GLK supports 4k@60 RGB@597Mhz well, as we have tested it with several other TVs and monitors. We are seeing this behavior on this TV only, and that's why I suspected if it's expecting something different. The UHD/Deep color mode is of operation is not clear to me yet. - Shashank</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>