Cavalier Mounts and Unconscious Riders

[Astellus the Traveler]

Forgive me if this has already been covered elsewhere on this site - I searched, but didn't find anything relevant.

How does a Cavalier mount behave after its rider has gone unconscious, but remains in the saddle?

I've just started DMing a Kingmaker game, and one of my players is a Cavalier. During the first session, his character was knocked unconscious, but managed to stay in the saddle. The player believed that, since Cav mounts are the equivalent of Druid animal companions, and since the last command he'd given to his mount was to attack this one particular foe, that it should keep attacking.

I ruled that the Cav's commands were via reins, knees, and shifted weight (which afaik is how one controls a horse in RL), and so when he went unconscious, his body was flopping around, giving the horse all kinds of mixed signals, and thus I had the horse leave combat.

Is there an "official" way to handle this situation?

[Frankthedm]

Covered under Mount rules.

If You Are Dropped: If you are knocked unconscious, you have a 50% chance to stay in the saddle (75% if you're in a military saddle). Otherwise you fall and take 1d6 points of damage. Without you to guide it, your mount avoids combat.

That paragraph covers both the possibility of falling out of the saddle and what the mount does if you are not guiding it.

[Prawn]

Could you teach it a trick, something to do if you fall unconscious?

Perhaps to keep fighting, or to take you to the cleric?