GRBOOT-GR765

Overview

GRBOOT-GR765 is an implementation of the ESA requirements document SAVOIR Flight Computer Initialisation Sequence (SAVOIR-GS-002). The software is developed in accordance with European Space Agency software engineerin gstandards ECSS-E-ST-40C and ECSS-Q-ST-80C, tailored software criticality category B (see Detailed features section).

Currently GRBOOT-GR765 has been validated on FPGA prototypes modelling the GR765 architecture. Necessary updates and validation will be re-executed once the GR765 microprocessor becomes available. See GR765 product page for more information about GR765.

Use cases

‍‍Boot loader. This is the baseline use case and provides reliable application loading meeting common requirements for booting payload and on-board flight computers.
Boot loader with maintenance (standby) mode. An extension point is available which allows for implementation of a custom software controlled maintenance mode which executes from ROM. It can for example be used to manage on-board memories over a network, such as PUS over SpaceWire using the available standby implementation described above.
ROM resident application. In this use case, the application is linked directly into the GRBOOT image and no application is loaded from external memory. It is useful for smaller control-type applications where a robust run-time is required.

Architecture

Key Tech Spec

Target technology support

Evaluation boards

Ordering information

Development Kit

Licensing

Software

Tools

Block diagram

Supported Hardware

Configuration

Reference Design

Other resources

Detailed features

Quality

‍‍Implements the ESA "SAVOIR Flight Computer Initialisation Sequence" (SAVOIR-GS-002). With tracing to GRBOOT technical requirements, design units, code and tests.
Developed in accordance with ESA software engineering standards ECSS-E-ST-40C and ECSS-Q-ST-80C, tailored software criticality category B.
- The deviations from full Category B are clearly documented by the tailoring matrix and NCRs, some of which are temporary until the re-validation on GR765 silicon has been performed. A nonconformance report is available upon request.
GRBOOT-GR765 is undergoing an Independent Software Validation and Verification (ISV&V) executed by 3rd party and managed by ESA. Please contact us for information about delta-ISVV.

Functionality

‍‍Multi-processor support (SMP, AMP)
Prepares environment compatible with multiple operating system (RTEMS, VxWorks, Linux, BCC, PikeOS, etc.)
Initialization: CPU, FPU, caches, peripherals, etc.
System self-tests: CPU, L1/L2 caches, ROM, external memories, etc.
- L1/L2 sub tests are pending updates for when the final GR765 hardware becomes available
Self-test results are recorded in a Boot report, available to the loaded application.
Separation of Boot Memory and Application Storage Memory: Updating application does not require updating the boot loader.
Application images are integrity checked before execution, with failover on failure.
Application images can be stored in local non-volatile memory
- parallel FLASH memories are directly supported while SPI and other memories require custom drivers
Application software pre-loader unit:
- Isolates the reading of application storage memory from the loading and checking of the ASW image
- The storage access implementation facilitates the creation of custom routines to access application memories (ex. over SpaceWire), or less rad-hard memories (like NAND memories).
- Simplifies image checking and error handling by performing them in isolated steps
ELF-like application image format with support for in-flight patching
An API allows to store parameters in non-volatile memory
- Enables fast boot
User extension points for custom initialization and user defined Standby Mode.
SpaceWire/PUS Standby software (optional, GRBOOT-STANDBY license)

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