Mori Seiki TV30 tool carousel setup problem.

Yes first orient spindle, then move Z axis in to position and then home ATC. I have set NO_FORCE_HOMING=1

I suddenly noticed this: halui.joint.N.home bit in so maybe I could use that to home atc at later stage.... have to try it out

Yes that should work.
You could connect halui.joint.N.home to motion.digital-out-nn and create an Mcode remap that orients the spindle, moves the Z axis into position and issues M64 Pnn to initiate homing of the ATC.

as far as i remember the toolchanger uses a MDS-A-SVJ-06 servo drive with HA-ME73 servo motor. it is an oldish motor equipped with an incremental encoder, so it has to be homed each startup.
i suggested to add a joint to it and use linuxcnc's built it homing, but then realized that it's impossible without adding a corresponding axis...
the drive is position controlled. so my approach would be to implement a hal component with pins:

speed limit
acceleration limit
home input
homed output
target position input
at-position output

then at startup you would assert "home", wait for "homed". and then set "target position" and wait for "at-position" when needed...

Yes exactly that setup. I may have to tinker on what you mentioned, but I am not sure how I can drive that axis to home it if it requires position commands? or is there any examples how to do it which I could take a look of? currently I am kind counting position one "step" forward and checking if limit switch has engaged during that step and if not it continues to increment position command value.

i would implement the component as a state machine. from the idle it would check the "home" pin and if true, move to, say, home1 state.
mimic the linuxcnc homing behavior. you'll have home_search_velocity and home_latch velocity. something like

target_velocity = home_search_velocity;
dv = (target_velocity - current_velocity);
if (dv / fperiod > max_accel) dv = max_accel * fperiod
else if (dv / fperiod < -max_accel) dv = -max_accel * fperiod;
current_velocity += dv;
output_pos += current_velocity * fperiod;

you can have a look how linuxcnc does it:  github.com/LinuxCNC/linuxcnc/blob/master.../emc/motion/homing.c

Is the "carousel" HAL component any help here?

linuxcnc.org/docs/2.8/html/man/man9/carousel.9.html

That can be configured to home itself on the first tool request, for example.