SPRADD1A August   2023  – September 2024 AM620-Q1 , AM623 , AM625 , AM625-Q1 , AM625SIP , AM62A3 , AM62A3-Q1 , AM62A7 , AM62A7-Q1 , AM62P , AM62P-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
  5. 2 Installing the SDK
  6. 3 Configuring the SDK for a Custom Board
  7. 4 Starting U-Boot Board Port
    1. 4.1 Introduction to Devicetrees
    2. 4.2 Capabilities of the Minimal Configuration
    3. 4.3 Preparing Custom Board Files
    4. 4.4 Initial Devicetree Modifications
    5. 4.5 Building U-Boot Binaries
    6. 4.6 U-Boot Deployment Instructions
  8. 5 Expanding the Custom Board Devicetree
    1. 5.1 Devicetree Configuration
    2. 5.2 Describing Peripherals in Nodes
    3. 5.3 Revising the Devicetree Configuration
  9. 6 Booting the Linux Kernel
    1. 6.1 Kernel Boot Overview
    2. 6.2 Kernel Deployment Instructions
  10. 7 Tools and Debugging
    1. 7.1 Kernel Debug Traces
    2. 7.2 OpenOCD Debugging
  11. 8 Future Work
  12. 9 Summary
  13. 10References
  14.   Revision History

5 Expanding the Custom Board Devicetree

At this point basic board functionality and the UART configuration have been validated by sucessfully loading U-Boot. In order to load Linux, which is much larger, a faster peripheral or block memory device is needed. Configuring this peripheral is the next step in the iterative bring-up process. Using Ethernet as an example, this section demonstrates how to add a new peripheral. Ethernet is a complex peripheral to configure, and it serves as a good example to understand the devicetree resources that may be required to configure other devicetree peripheral nodes. It will be simpler to start with a peripheral like SD, eMMC, or USB if those are available on the custom board. A sample SD configuration is included in the minimal configuration and may already be functional if the custom board has SD capability.