Only part of HDMI outputs detected

[eNca]

Hi All,

I have Gentoo Linux installed on MacBookPro11,2
It has three connectors for external displays.
Two of them are mini displayports which are recognized by xrandr as DP1, DP2, HDMI1 and HDMI2.
The third one is HDMI port which is recognized by xrandr as HDMI3.

HDMI1 and HDMI2 works partialy - the system is not able to recognize resolution of the external display. But it is not an issue because the HDMI3 worked well till today.

Today I was rebooted my notebook after approx. 20 days and after reboot the xrandr recognize only DP1, DP2, HDMI1, HDMI2 but no HDMI3.
And the display connected to the HDMI port shows nothing.

I'm not sure what all happens from the last reboot but there are some changes which I remember:

• I have upgraded lot of packages including linux-firmware (I don't know if it is important or not). I have tried to downgrade back to the previous version but it does not help.
  
• I have uninstalled kdeconnect package and all of their kde-* dependencies (I'm using xfce) - I hope it cannot have any connection to my problem
  

I'm sure that I'm still using the same kernel gentoo-sources 4.14.65 build via genkernel.

The hardware is OK - when I reboot to the Mac OS then the HDMI port works well (the same cable and monitor).

When I close the lid and restart computer then the very first phase of boot is displayed on the external display attached via HDMI but soon (still during the boot process) the external display switch to black screen and from this moment it shows nothing.

Some info about the system:
dmesg output
xrandr output
emerge --info
/etc/make.conf

Any help will be appreciated

[eNca]

After next