We already have a Deprecated Interfaces removal policy for core interfaces: https://trustedfirmware-a.readthedocs.io/en/latest/about/release-information.html#removal-of-deprecated-interfaces although this is not quite the same for platforms the proposed purpose is similar of a managed removing of something that someone has a use case for in the short term.

The Arm platforms as mentioned by Manish are targeted as reference platforms for other project users to inspect which is perhaps a little different than other platform providers. So I think it is appropriate to have a transition period as those references platforms become outdated and normally replaced as it is with the sgm775 with the tc0 platform.  I can understand for other platform providers they might want a more accelerated or removal approach and that’s fine I think.

I’m not suggesting we need to create a formal policy but leave it up to individual platform providers to decide how they manage their platforms as they know best how they are used.

Ensuring that the OpenCI is not left in a broken state from a build or test perspective during a deprecation period is of course necessary and the steps suggested by Manish look reasonable to me.

Hope this helps on the intent here.

Joanna

From: TF-A <tf-a-bounces@lists.trustedfirmware.org> on behalf of Varun Wadekar via TF-A <tf-a@lists.trustedfirmware.org>
Reply to: Varun Wadekar <vwadekar@nvidia.com>
Date: Thursday, 11 March 2021 at 22:12
To: Manish Pandey2 <Manish.Pandey2@arm.com>
Cc: "tf-a@lists.trustedfirmware.org" <tf-a@lists.trustedfirmware.org>
Subject: Re: [TF-A] Deprecating Arm's sgm775 platform

Hi,

I was wondering if there is any value in keeping non-compiling code in the tree, hence the question. For Tegra it is straight forward, so it would be easy to pull the plug.

-Varun

From: Manish Pandey2 <Manish.Pandey2@arm.com>
Sent: Thursday, March 11, 2021 2:44 AM
To: Varun Wadekar <vwadekar@nvidia.com>
Cc: tf-a@lists.trustedfirmware.org
Subject: Re: Deprecating Arm's sgm775 platform

External email: Use caution opening links or attachments

Hi Varun,

For Arm reference platforms, we are not sure who all are using it. That is why i proposed to keep in repo for around a year before deleting it.

But for NV platforms, if you are sure that nobody is going to require it, you can delete it earlier.

Also, instead of proposed step 2 earlier we can have an alternate

-  2. Don't allow it to be built by default. (introducing PLATFORM_DEPRECATED build macro)

+ 2. Instead of purposefully failing the build we can print a warning message (It's also quite possible that someday during cooling off period it stops to build naturally)

thanks

Manish

---

From: Varun Wadekar <vwadekar@nvidia.com>
Sent: 11 March 2021 02:35
To: Manish Pandey2 <Manish.Pandey2@arm.com>
Cc: tf-a@lists.trustedfirmware.org <tf-a@lists.trustedfirmware.org>
Subject: RE: Deprecating Arm's sgm775 platform

Hi Manish,

Just curious, what would be the reason to keep the platform alive for 2 release cycles? I have one Tegra platform that needs to be deprecated and so would like to understand the thought process.

-Varun

From: TF-A <tf-a-bounces@lists.trustedfirmware.org> On Behalf Of Manish Pandey2 via TF-A
Sent: Tuesday, March 9, 2021 2:01 PM
To: tf-a@lists.trustedfirmware.org
Subject: [TF-A] Deprecating Arm's sgm775 platform

External email: Use caution opening links or attachments

Hi,

The purpose of the email is to notify about deprecation of sgm775 platform and proposed process for deprecating a platform.

Arm's System Guidance for Mobile(SGM-775) is an old platform and no longer maintained. It is superseded by Total Compute(tc0) platform.

Proposal for deprecating a platform:

1. Keep the code in repository. (at least for 2 release cycles)

2. Don't allow it to be built by default. (introducing PLATFORM_DEPRECATED build macro)

3. Disable CI testing.

4. Create appropriate documentation for deprecated platforms.

Let me know if you have any suggestions.

Thanks

Manish P