| Logging Service |
| ================= |
| The Logging service is intended to be a mechanism that provides a means to print in the context |
| of a secure partition. All other secure partitions in a given environment will utilize a |
| handler to push any data to this SP. The current default behavior is where the logging service |
| will send the data to a UART peripheral viewable by a terminal device (see: :ref:`UART backend`). |
| |
| In case the logging with the logging SP fails (e.g. in case the logging SP is not deployed, still |
| booting, etc.) log messages fall back to the default logging mechanism. |
| |
| UART backend |
| ------------ |
| The UART backend for the logging SP outputs the log messages to an UART device. It relies on an |
| UART platform adapter that provides a generic interface to interact with an UART device. |
| The exact driver implementation is to be provided by the platform. |
| The platform specific driver configuration (base-address) is hosted in the SP manifest. |
| Platform code is responsible for reading the config data from the config store upon boot. |
| Currently a PL011 driver is provided for the *AEM FVP* platform. |
| |
| Testing the Logging Service |
| ------------------------------- |
| Component-Level Test Suites |
| ''''''''''''''''''''''''''' |
| The logging components will be targeted by component-test and unit-test cases. |
| |
| Service-Level Test Suites |
| ''''''''''''''''''''''''' |
| *ts-service-test* may implement logging service calls, although verifying the log messages would |
| be difficult, so the scope is limited. (Unit and component test cases can account for this.) |
| |
| Environment Tests |
| ''''''''''''''''' |
| The logging SP's UART backend relies on the UART peripheral. Test have been added to the |
| *env_test* SP deployment to check the basic functionality of the UART device, but the |
| verification of the results is not possible, as the peripheral does not provide a way |
| (e.g. error bit) to check whether the printing (*putc*) was successful. |
| Tests included in the *env_test* SP deployment may be invoked from Linux user-space using the |
| *ts-remote-test/arm-linux* deployment. |
| |
| |
| *Copyright (c) 2023, Arm Limited and Contributors. All rights reserved.* |
| |
| SPDX-License-Identifier: BSD-3-Clause |