Hi,

Continuing splitting TF-M build process we got alternative idea which make a step further to already proposed.

The key idea is an extension of TF-M installation phase with a copy of NS platform source code and let NS developer focus on that small subset of code only leaving TF-M complexity aside. This approach opens several attractive features like

• TF-M S and NS source codes trees became independent including build scripts.
• TF-M S and BL builds only once (separately) making NS development lightweight.
• Simplifies toolchains because of no need to manage different MPUs cores.
• Allow platform owner distribution of S and BL parts in binaries with NS platform sources and PSA API.
• NS build will not interfere with S build and allows to use different build system for NS App hence IDE friendly.
• Compatible with the current (mixed) build and can co-exist in parallel.

The drawback or side-effect of this approach is the need to run 2 independent builds: for S and NS sides.

I plan to talk about it with details on the next tech forum on May 25 but wish to have a preliminary discussion here with

Here is the PoC of the proposal for an521: https://review.trustedfirmware.org/c/TF-M/trusted-firmware-m/+/20960

The NS built will not run probably but functional completeness was not the goal of PoC.

Thanks, and looking for feedback,

Anton

From: David Hu via TF-M <tf-m@lists.trustedfirmware.org>
Sent: Wednesday, May 18, 2022 4:26 AM
To: Bohdan.Hunko@infineon.com; tf-m@lists.trustedfirmware.org
Cc: nd <nd@arm.com>
Subject: [TF-M] Re: Split build

Hi Bohdan,

It is still a prototype so far.

Some major features underway may impact TF-M structure and build system as well. So the current plan is to resume the build split after those major features are merged.

May I know if you have any specific requirement or dependencies on the build split?

Perhaps we can take a look if some optimization can be performed in advance.

Best regards,

Hu Ziji

From: Bohdan.Hunko--- via TF-M <tf-m@lists.trustedfirmware.org>
Sent: Tuesday, May 17, 2022 11:48 PM
To: tf-m@lists.trustedfirmware.org
Subject: [TF-M] Split build

Hi everyone,

Some time ago patch for split build of SPE, NSPE, BL2 was announced.

I am interested on when this patch is planned to be merged?

Regards,

Bohdan Hunko

Cypress Semiconductor Ukraine

Engineer

CSUKR CSS ICW SW FW

Mobile: +38099 50 19 714
Bohdan.Hunko@infineon.com