display not working correctly

[raob]

After building AOSP android-11.0.0_r36 and installing (and SW_binaries_for_Xperia_Android_11_4.14_v5b_yoshino.img) - upon boot up the screen is very dark ( but does actually "flash" from very dark to a little bit lighter)..
Once the system has booted the screen brief turns on - every time i hit the power button - text is red.. but enough should that i can see where the power button is to switch it off. Due to the screen not being on for than half a second it essentially not usable... I see there's a new release today so i will rebuild to r38 over the coming week.