feat: linux: Add docs on OP-TEE Secure Storage

[jsuhaas22]

OP-TEE provides secure storage mechanism. Add docs to explain what it is, its uses and how to compile it.

[shiva-ti]

there's already a section for OPTEE Secure storage in docs - https://software-dl.ti.com/processor-sdk-linux/esd/AM62X/latest/exports/docs/linux/Foundational_Components_OPTEE.html#secure-storage-with-rpmb-for-hs

can we update that itself ? Same can either be linked in the Security overview section, or if you want to add a new security specific rst it can be linked to the existing one, something like - "for more details refer - security specific rst"

[jsuhaas22]

there's already a section for OPTEE Secure storage in docs - https://software-dl.ti.com/processor-sdk-linux/esd/AM62X/latest/exports/docs/linux/Foundational_Components_OPTEE.html#secure-storage-with-rpmb-for-hs

can we update that itself ? Same can either be linked in the Security overview section, or if you want to add a new security specific rst it can be linked to the existing one, something like - "for more details refer - security specific rst"

That section is only for RPMB. I could make it more generic for secure storage and copy this there, though. I wrote a separate page since it was getting long and I didn't want the main page (focused on compilation) to digress. There are links between these two pages in this PR.

[shiva-ti]

there are some passive voice warnings generated - https://github.com/TexasInstruments/processor-sdk-doc/pull/539/files , please review all those as well

[jsuhaas22]

there are some passive voice warnings generated - https://github.com/TexasInstruments/processor-sdk-doc/pull/539/files , please review all those as well

Done @shiva-ti, the remaining warnings that cause Vale to fail are all "acronym not defined", though I have defined them... or sentence-style capitalization.

[shiva-ti]

there are some passive voice warnings generated - https://github.com/TexasInstruments/processor-sdk-doc/pull/539/files , please review all those as well

Done @shiva-ti, the remaining warnings that cause Vale to fail are all "acronym not defined", though I have defined them... or sentence-style capitalization.

LGTM, please also mention the platforms in commit message for which you are adding this support

[manorit2001]

Hi @jsuhaas22 , My honest recommendation would be to update https://optee.readthedocs.io/en/latest/architecture/secure_storage.html if something is lacking there in the generic flow for secure storage and have only TI specific overrides ( if we have ) to be documented in TI specific pages. This helps in easier maintenance when upstream migrates and changes and only the TI specific stuff we have to maintain. Also benefits the general community if something is lacking upstream.

[jsuhaas22]

Hi @jsuhaas22 , My honest recommendation would be to update https://optee.readthedocs.io/en/latest/architecture/secure_storage.html if something is lacking there in the generic flow for secure storage and have only TI specific overrides ( if we have ) to be documented in TI specific pages. This helps in easier maintenance when upstream migrates and changes and only the TI specific stuff we have to maintain. Also benefits the general community if something is lacking upstream.

Done @manorit2001 . I have trimmed this PR down.

[manorit2001]

Acked

[StaticRocket]

Alright, this seems fine to me now. Just need to resolve the merge conflict @jsuhaas22

[cshilwant]

@jsuhaas22 can you resolve the merge conflicts?

@shiva-ti to re-review

[jsuhaas22]

I rebased on master. cc: @shiva-ti @cshilwant @StaticRocket