| Gyorgy Szing | db9783c | 2019-04-17 21:08:48 +0200 | [diff] [blame] | 1 | ######################################################### |
| 2 | Generic OS migration from Armv7-M to Armv8-M architecture |
| 3 | ######################################################### |
| 4 | The purpose of this document is to list a set of requirements needed for |
| 5 | migrating a generic OS kernel running on Armv7-M to the Armv8-M architecture. |
| 6 | |
| 7 | ******************** |
| 8 | List of requirements |
| 9 | ******************** |
| 10 | - If the same OS codebase is used for both Secure and Non Secure builds, it is |
| 11 | suggested to put specific code targeted to the Non Secure build under a |
| 12 | compile time switch, e.g. ``#if (DOMAIN_NS == 1U)``. The OS build system in |
| 13 | this case needs to be amended accordingly to support this new switch. |
| 14 | - If the OS implements stack limit checking, the ``PSPLIM`` register |
| 15 | needs to be initialized and properly handled during thread context switch |
| 16 | operations. |
| 17 | - If the OS manipulates directly the Link Register, the default Link Register |
| 18 | value used in Handler mode transitions needs to be differentiated between |
| 19 | Secure and Non Secure builds, i.e. ``0xFD`` and ``0xBC``, respectively. |
| Anton Komlev | 0dbe8f1 | 2022-06-17 16:48:12 +0100 | [diff] [blame] | 20 | - If the OS manages the non-secure client identification, please check the |
| Anton Komlev | 3356ba3 | 2022-03-31 22:02:11 +0100 | [diff] [blame] | 21 | :doc:`Non-secure Client Extension Integration Guide </integration_guide/non-secure_client_extension_integration_guide>`. |
| Gyorgy Szing | db9783c | 2019-04-17 21:08:48 +0200 | [diff] [blame] | 22 | |
| 23 | -------------- |
| 24 | |
| Summer Qin | abf6698 | 2021-04-06 17:22:15 +0800 | [diff] [blame] | 25 | *Copyright (c) 2018-2021, Arm Limited. All rights reserved.* |