| Platform Compatibility Policy |
| ============================= |
| |
| Introduction |
| ------------ |
| |
| This document clarifies the project's policy around compatibility for upstream |
| platforms. |
| |
| Platform compatibility policy |
| ----------------------------- |
| |
| Platform compatibility is mainly affected by changes to Platform APIs (as |
| documented in the `Porting Guide`_), driver APIs (like the GICv3 drivers) or |
| library interfaces (like xlat_table library). The project will try to maintain |
| compatibility for upstream platforms. Due to evolving requirements and |
| enhancements, there might be changes affecting platform compatibility which |
| means the previous interface needs to be deprecated and a new interface |
| introduced to replace it. In case the migration to the new interface is trivial, |
| the contributor of the change is expected to make good effort to migrate the |
| upstream platforms to the new interface. |
| |
| The deprecated interfaces are listed inside `Release information`_ as well as |
| the release after which each one will be removed. When an interface is |
| deprecated, the page must be updated to indicate the release after which the |
| interface will be removed. This must be at least 1 full release cycle in future. |
| For non-trivial interface changes, an email should be sent out to the `TF-A |
| public mailing list`_ to notify platforms that they should migrate away from the |
| deprecated interfaces. Platforms are expected to migrate before the removal of |
| the deprecated interface. |
| |
| -------------- |
| |
| *Copyright (c) 2018-2019, Arm Limited and Contributors. All rights reserved.* |
| |
| .. _Porting Guide: ../getting_started/porting-guide.rst |
| .. _Release information: ./release-information.rst#removal-of-deprecated-interfaces |
| .. _TF-A public mailing list: https://lists.trustedfirmware.org/mailman/listinfo/tf-a |
