Unfortunately the TPM story for the raspberry pi… isn’t, really. It doesn’t come with one, and while it does support secure boot, it’s incredibly limited and more akin to what you’d find in a microcontroller (you can burn vendor keys to EEPROM). So all that to say, it would be kind of pointless, unfortunately.

I’d you’re interested in this, I know systemd has been working pretty hard on getting TPM-provisioned credentials usable on Linux though!