How and when is `/sys/kernel/security/tpm0/binary_bios_measurements` exposed?

Currently, I try to understand how a measured boot is working and what components log what in which pcr of a tpm2. I have a test-setup with uefi-secure boot enabled and a tpm2 attached in a kvm virtualized machine. I compiled my own kernel with tpm support etc. tpm2_pcrread gives reasonable output. Now I want to look inside the events of the tpm. But there is no /sys/kernel/security/tpm0 and therefore no binary_bios_measurement. If I live boot from the ubuntu 23.10 iso, the file is present and can be read by tpm2_eventlog. So i take the kernel from ubuntu and booted the system with it, but also here, there is no /sys/kernel/security/tpm0. No my guess is, that i miss kernel module that exposes this. Or systemd in ubuntu creates this path. I do not find any documentation about this. I do not know how to find out where and who creates this path/file. Does someone know how to expose the binary_bios_measurement? PS. on my own linux I am using OpenRc and not systemd.