Question regarding optee-ftpm TA recipe

Hello, 

I recently updated my BSP to a more recent version of Kirktone 
which leads me to use the new optee-ftpm_git recipe. This one is based 
on Microsoft/ms-tpm-20-ref while the older recipe was using MSRsec 
(changes introduced by [1]). 

After this change I could not boot my target anymore and had no 
meaningful errors. I finally figured out that one of the 4 
"Authentication passed" messages was missing compared to the secure-boot 
documentation from TI regarding the AM64x [2]. 
I manage to link this to a problem with the bl32.bin file, which is 
actually much smaller when using the new version of the optee-ftpm 
recipe (0.7MiB against 1.2MiB with the recipe using MSRsec). I solved my 
issue by reverting [1], but I would prefer not to do so since MSRsec 
looks to be not maintained anymore. 

When looking at the MSRsec repo, we can see it uses ms-tpm-20-ref as a 
submodule, so I wonder if we can really use ms-tpm-20-ref alone as is 
currently done. In addition, I saw that the recipe from the master 
branch has changed to introduce the new optee_ftpm from OP-TEE in 
addition to ms-tpm-20-ref. 

Do you know if the recipe from the Kirktone branch is applicable in my 
case (AM64) or if I absolutely need to backport the recipe from master 
to make the fTPM work? 

[1]: optee-ftpm: Use the latest fTPM sources 
commit: 3ee7d019898854f776f95ed31f4b7ea8c8a73dfe 
[2]: https://software-dl.ti.com/processor-sdk-linux/esd/AM64X/latest/exports/docs/linux/Foundational_Components_Secure_Boot.html#secure-boot-flow