after reading about how to upgrade & root the Xperia SP on the 4.3 firmware I followed the guides to get everything set up.
Now, after being nearly there I'm stuck with a black booting screen.
Here follow the steps I did undertake so far, any help to resolve my issue would be very welcome.
I started with firmware 12.0.A.2.245 rooted with Doomlords method (flash old kernel, root, flash .245 kernel again)
1 backup contacts/messages etc
2 do TA partition Backup with Backup-TA
3 update firmware using PC-Companion
4 unlock bootloader with official sony guide
5 fastboot flash cwm / superSU
---> everything worked fine so far (phone was operational), now I wanted to get the screen mirroring working - meaning the bravia engine. So I went for
6 Backup-TA check backup integrity with dry restore
7 Backup-TA restore TA partition
last step of the restore was: reboot device, which got me to the black screen - which is where I am stuck now.
All I managed so far is entering the fastboot mode, I could confirm this working by issuing a "fastboot devices" which listed the phone as available.
Anyone got any ideas to what went wrong and how to fix this?