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Soby Mathew02bdbb92018-09-26 11:17:23 +01001TF-A Platform Compatibility Policy
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10--------------
11
12Introduction
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14
15This document clarifies the project's policy around compatibility for upstream
16platforms.
17
18Platform compatibility policy
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20
21Platform compatibility is mainly affected by changes to Platform APIs (as
22documented in the `Porting Guide`_), driver APIs (like the GICv3 drivers) or
23library interfaces (like xlat_table library). The project will try to maintain
24compatibility for upstream platforms. Due to evolving requirements and
25enhancements, there might be changes affecting platform compatibility which
26means the previous interface needs to be deprecated and a new interface
27introduced to replace it. In case the migration to the new interface is trivial,
28the contributor of the change is expected to make good effort to migrate the
29upstream platforms to the new interface.
30
31The `Release information`_ documents the deprecated interfaces and the intended
32release after which it will be removed. When an interface is deprecated, the
33page must be updated to indicate the release after which the interface will be
34removed. This must be at least 1 full release cycle in future. For non-trivial
35interface changes, a `tf-issue`_ should be posted to notify platforms that they
36should migrate away from the deprecated interfaces. Platforms are expected to
37migrate before the removal of the deprecated interface.
38
39--------------
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41*Copyright (c) 2018, Arm Limited and Contributors. All rights reserved.*
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43.. _Porting Guide: ./porting-guide.rst
44.. _Release information: https://github.com/ARM-software/arm-trusted-firmware/wiki/TF-A-Release-information#2removal-of-deprecated-interfaces
Soby Mathewf1e6c492018-10-02 14:01:03 +010045.. _tf-issue: https://github.com/ARM-software/tf-issues/issues