HDMI RX for 1080p 30fps

[GordonXu]

Hi,

I'm trying HDMI RX function on i.MX8QM MEK. OS version is 5.15.71.

1080p 60fps works well.

But for 1080p 30fps, it failed with messages,

hdmirx_get_stable_tmds() timeout
detect tmds clock failed
PHY configuration failed

Any suggestions or comments?

Thanks
Gordon

[GordonXu]

Thanks all the replies!

After tuning the clock of HDMI Signal Generator and adding the AVI info frame  into HDMI Signal Generator, all things are doing well. 

[Sanket_Parekh]

Hello @GordonXu ,

I hope you are doing well.

I'm glad to help you.

"After tuning the clock of the HDMI Signal Generator and adding the AVI info frame into HDMI Signal Generator, all things are doing well. "
->This will surely help others.

I'm glad the issue is resolved now, hence can I close this thread?

Thanks & Regards,

Sanket Parekh

[GordonXu]

Thanks to @Sanket_Parekh!

After tuning the HDMI Signal Generator, TMDS clock freq detected correctly.

But "PHY configuration failed" is still there.

I found in document, IMX8QMIEC Rev. 2, 02/2023
4.10.8 HDMI Rx module
The module passes CTS 1.4 (up to 3.4 Gbps) tests such as TMDS min/max differential swing tolerance, intra-pair skew, and jitter tolerance. However, HDMI-RX is not certified because the IP does not support DVI mode and cannot detect the video timing. In DVI mode, without the AVI info frame, detection of the video mode utilized is not possible. In addition, only HDCP 2.2 is supported.

Does that mean the signal generator should send "AVI info frame", otherwise HDMI RX of iMX8 won't work?

Regards

Gordon

[Sanket_Parekh]

Hello Customer,

I hope you are doing well.

->If still, a PHY configuration failed error occurs it means bringing up the sequence for the HDMI-rx still doesn't work the way it should.
->Please Check the hdmirx pointer values that are put into ret variable which causing this error.

Thanks & Regards,

[GordonXu]

Thanks to @Sanket_Parekh !

After tuning the HDMI signal generator, TMDS clock freq detected correctly.

But "PHY configuration failed" is still there.

Messages are as following,

root@imx8qmmek:~# [ 56.914253] mxc-hdmi-rx 58268000.hdmi_rx: HDMI RX Cable Plug In
[ 56.923441] mxc-hdmi-rx 58268000.hdmi_rx: Doing initial PHY configuration
[ 56.930517] mxc-hdmi-rx 58268000.hdmi_rx: Releasing PHY reset
[ 56.936337] mxc-hdmi-rx 58268000.hdmi_rx: Waiting for pma_cmn_ready
[ 57.361207] mxc-hdmi-rx 58268000.hdmi_rx: hdmirx_wait_edid_read wait for EDID to be read
[ 59.769932] mxc-hdmi-rx 58268000.hdmi_rx: TMDS change detect: -1 -> 147996
[ 59.769932]
[ 59.818182] mxc-hdmi-rx 58268000.hdmi_rx: Detect TMDS clock freq: 148007 kHz
[ 59.825278] mxc-hdmi-rx 58268000.hdmi_rx: VCO frequency (refclk: 24000 kHz, TMDS clk: 148007 kHz, OSR: 4, tmds_bit_clk_ratio: 10) equals 5923172 kHz
[ 62.568030] mxc-hdmi-rx 58268000.hdmi_rx: PHY configuration failed
[ 62.818263] mxc-hdmi-rx 58268000.hdmi_rx: TMDS change detect: -1 -> 148007
[ 62.818263]
[ 62.869451] mxc-hdmi-rx 58268000.hdmi_rx: Detect TMDS clock freq: 147996 kHz
[ 62.876537] mxc-hdmi-rx 58268000.hdmi_rx: VCO frequency (refclk: 24000 kHz, TMDS clk: 147996 kHz, OSR: 4, tmds_bit_clk_ratio: 10) equals 5922731 kHz
[ 65.618933] mxc-hdmi-rx 58268000.hdmi_rx: PHY configuration failed
[ 65.866679] mxc-hdmi-rx 58268000.hdmi_rx: TMDS change detect: -1 -> 147996
[ 65.866679]
[ 65.918597] mxc-hdmi-rx 58268000.hdmi_rx: Detect TMDS clock freq: 148007 kHz
[ 65.925681] mxc-hdmi-rx 58268000.hdmi_rx: VCO frequency (refclk: 24000 kHz, TMDS clk: 148007 kHz, OSR: 4, tmds_bit_clk_ratio: 10) equals 5923172 kHz
[ 68.668037] mxc-hdmi-rx 58268000.hdmi_rx: PHY configuration failed
[ 68.677198] mxc-hdmi-rx 58268000.hdmi_rx: Doing initial PHY configuration
[ 68.684242] mxc-hdmi-rx 58268000.hdmi_rx: Releasing PHY reset
[ 68.690025] mxc-hdmi-rx 58268000.hdmi_rx: Waiting for pma_cmn_ready
[ 69.113451] mxc-hdmi-rx 58268000.hdmi_rx: hdmirx_wait_edid_read wait for EDID to be read
[ 71.565678] mxc-hdmi-rx 58268000.hdmi_rx: TMDS change detect: -1 -> 148007
[ 71.565678]
[ 71.613819] mxc-hdmi-rx 58268000.hdmi_rx: Detect TMDS clock freq: 148007 kHz
[ 71.620900] mxc-hdmi-rx 58268000.hdmi_rx: VCO frequency (refclk: 24000 kHz, TMDS clk: 148007 kHz, OSR: 4, tmds_bit_clk_ratio: 10) equals 5923172 kHz
[ 74.363722] mxc-hdmi-rx 58268000.hdmi_rx: PHY configuration failed
[ 74.613958] mxc-hdmi-rx 58268000.hdmi_rx: TMDS change detect: -1 -> 148007

Regards

Gordon

[Sanket_Parekh]

Hello @GordonXu ,

I hope you are doing well.

->In i.mx8QM ,HDMI Rx function supports up to 4k2k at 60Hz & pixel clock upto 600 Mhz.
->The first "hdmirx_get_stable_tmds() timeout error" casue of the cdns_hdmirx_get_stable_tmds function's calls off.
->Because the function hdmirx_config is trying the config the hdmi rx function and when it tries to get tmds clock frequency it should print the clock in Khz or fail.
->So as it failed to get the clock hdmirx->tmds_clk throws out the second error which is "detect tmds clock failed".
->Please look into that direction why it is not letting it set up the frequency.
->Please check if their clock is well set for the HDMI_RX function.

->Because when the Bring-up sequence for HDMI rx got followed up the hdmirx_config is got compared to whether the configuration is set within the time or not and it throws the third error "PHY configuration failed"

I hope it will help you.

Thanks & Regards,

Sanket Parekh