Introduction to an upgrade test solution for domain controllers

Preface

Traditional automotive ECUs use diagnostic flashing to implement software updates, and the data volume is relatively small, generally ranging from tens of KB to tens of MB. As the new four modernizations of automobiles continue to advance, the architecture of the domain controller or central computer on the car has evolved into an MPU/SOC+MCU solution, and the data volume for MPU/SOC software upgrades is often hundreds of MB or even several GB. Using DoIP plus diagnostic services (0x34, 0x36) to transmit upgrade package data is a cumbersome process and has low bandwidth utilization. Sending 36 services through DoIP requires waiting for the response of the transport layer, namely TCP ACK, and then waiting for DoIP's 0x8002 message (the simplified version does not use 0x8002). Finally, you must wait for the controller's diagnostic affirmative response before continuing to send data. Therefore, for upgrade packages with large data volumes, various manufacturers have adopted a variety of new methods to implement domain controller software upgrades.

Based on the existing experience, Shanghai Beihui Information introduces a new software upgrade technology and testing solution that abandons the traditional solution. This solution is based on the combination of "a protocol supporting SOA + traditional IT transmission protocol". Hereinafter referred to as "SOA protocol" and "IT protocol".

Domain Controller Upgrade Process Overview

Figure 1 Upgrade process diagram

As shown in the figure above, the upgrade of slave node domain control is initiated by the master node, and this process is mainly carried out in the car. The master node first establishes an upgrade task for the slave node through the "SOA protocol", then sends the upgrade package to the slave node through the "IT protocol", and controls the upgrade process through the "SOA protocol" at the same time; compared with the use of diagnostic services to achieve upgrades, this process is simple and efficient, and can quickly achieve the purpose of upgrading the software.

Test case composition

The upgrade test for slave nodes is mainly divided into the following parts: 1. Forward process test; 2. State jump test; 3. Fault code test; 4. Scenario test

Figure 2 Part of the test case

Main environment for domain controller upgrade testing

Beihui mainly uses Vector's CANoe+VN56xx to develop test cases and execute tests. With the addition of basic peripherals such as programmable power supply, the test environment can be quickly built. The schematic diagram is shown below:

Figure 3 Schematic diagram of the test environment

In the test script, CANoe is used to simulate the main node, mainly implementing the functions of the two modules "SOA Protocol" and "IT Protocol"; 1. Simulate CANoe as the main node and send "SOA Protocol" requests to DUT to control the upgrade process; 2. Simulate CANoe as the "IT Protocol" Server. After receiving the "IT Protocol" request from DUT, it sends the upgrade package to DUT through the "IT Protocol".

Figure 4 Test script diagram

Domain controller upgrade test instance

Data transmission process

After the CANoe simulation master node establishes an upgrade task for the slave node, the slave node sends the "IT protocol" to request the upgrade package path. The simulation master node responds to the upgrade package path, and the slave node sends the "IT protocol" to obtain the upgrade package. The simulation master node uses the "IT protocol" to send the upgrade package. During the transmission process, the SOA protocol can be used to periodically read the transmission progress. After waiting for the transmission to complete, the simulation master node sends an installation request and periodically reads the installation progress during the installation process. The following is an example of a test report and test data.

Figure 5: Create a task and transfer process test report

Figure 6 Installation upgrade package test report

Summarize

This article introduces an emerging technology solution for domain controller upgrade, which has been widely accepted and adopted in the field of automotive electronics. Compared with using diagnostic services to achieve upgrades, this solution has the following two main advantages:

1. The upgrade process is simple and efficient

2. Transmit upgrade packages more efficiently