<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - HDMI port is not working on current KMS driver with VX900 platform" href="https://bugs.freedesktop.org/show_bug.cgi?id=94528#c13">Comment # 13</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - HDMI port is not working on current KMS driver with VX900 platform" href="https://bugs.freedesktop.org/show_bug.cgi?id=94528">bug 94528</a> from <a class="email" href="mailto:huangranbj@126.com" title="HuangRan <huangranbj@126.com>"> HuangRan</a> <pre>With my past two weeks' work, I have finished analyzing HDMI port mode setting mode in via open source KMS driver. Actually the whole mode setting process phases can be divided into several phases: 1) EDID probe and EDID processing to generate a list of modes(CEA, EST, DTL, STD), then select the best mode to do the mode set. At the same time, in this phase, encoder and connector are chose out for HDMI port(that should be TMDS for encoder and HDMIA for the connector). And for via open source driver, it probes out the VBIOS information from the BIOS and get DI port informaiton(including VCP information) and get supported devices list and then I2C ping pang probe(For my VX900 board, it is S3_CRT|S3_DVI|S3_HDMI|S3_DP). After that it uses 0xC0C4, 0C0C8 registers to ask if the HDMI monitor is present, if that is so, probe 256 bytes EDID information and do analysis. 2) If we are using fb device, it will pick up correct crtc device for the HDMI encoder and connector. 3) then the control is given back to fb device, and real mode setting will be done. encoder and crtc funcs(prepare, mode_set, commit) will be done in this process. Especially some HDMI PHY registers are set and Info Frame registers are set(although audio registers are set) 4)after the commit of encoder is done, the monitor will be lighten up. So right now with the X logs for OpenChrome KMS driver, the EDID is probed out but the monitor is not showning anything, I thought the issue should be in the process 3). So I will begin to check OpenChrome KMS HDMI mode setting function to see if HDMI PHY and INFO Frame registers are set properly. The most difficult thing is that in VX900 OGPM, there is no registers definition for HDMI port and VIA does not plan to release it because of the IP protection. So I have to figure it out by my debugging and understanding. Thanks, Frank</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>