CM-T335: U-Boot: Firmware Update

Introduction

The CompuLab CM-T335 System-on-Module / Computer-on-Module Firmware consists of two components: Secondary Program Loader (SPL) and U-Boot. This article describes the firmware update process for CM-T335 system-on-module product.

Preliminary setup

• Make sure to power off the CM-T335 evaluation platform.
• Connect the host PC to the SB-T335 base-board (connector P11) via the serial cable supplied with the evaluation kit.
• Start terminal emulation software on your PC. Set baud rate to 115200 bps, 8 bit per frame, 1 stop bit, no parity, no flow control.
• Turn on the CM-T335 evaluation system. The U-Boot boot-loader will start and you will get a command prompt in the terminal window.

If the boot settings of your CM-T335 are different than default, you may need to press and hold ^C while turning the CM-T335 on, in order to get command prompt.

Updating Firmware on the micro SD card

The firmware can be updated using a workstation with a micro SD card reader, or using CM-T335 module Linux environment.

• To update the SPL, just replace it's binary file (MLO) on the micro SD card with the desired version.
• To update the U-Boot, just replace the U-Boot binary file (u-boot.img) on the micro SD card with the desired version.
• Plug the micro SD card into the micro SD card socket of the SB-T335.
• Reset/power on the CM-T335 evaluation system to boot the updated firmware.

Updating Firmware on the NAND flash

CM-T335 firmware can be updated from a micro SD card or using network TFTP download. Both methods are performed from the U-Boot command line and include following common steps:

1. Loading binary images from the selected media to the CM-T335 DRAM
2. Flashing images to the on-board NAND flash

Updating from micro SD card

• Copy the firmware binary images MLO and u-boot.img from U-Boot package for CM-T335 to the root directory of the micro SD card.

The partition has to be formatted with either ext2/3/4 or FAT file system.

• Insert the micro SD card into the micro SD socket (P23) on SB-T335.
• Start the U-Boot MMC subsystem:

# mmc rescan

• Check that the storage device is ready:

# ls mmc 0:1

• Load the SPL binary into memory:

# load mmc 0:1 80a00000 mlo

• Load the U-Boot binary into memory:

# load mmc 0:1 80100000 u-boot.img

• Proceed to Flashing images section

Updating from USB

• Copy the firmware binary images MLO and u-boot.img from U-Boot package for CM-T335 to the root directory of the first partition on the USB storage device.

The partition has to be formatted with either ext2/3/4 or FAT file system.

• Plug the USB storage device into:
  • USB host connector (either P25, P26, P27 or P28) on SB-T335 if the CM-T335 module has U4 configuration or
  • USB OTG connector (P19) on SB-T335 if the CM-T335 module has U1 configuration
• Start the U-Boot USB subsystem:

# usb start

• Check that the storage device is ready:

# ls usb 0:1

• Load the SPL binary into memory:

# load usb 0:1 80a00000 mlo

• Load the U-Boot binary into memory:

# load usb 0:1 80100000 u-boot.img

• Proceed to Flashing images section

Updating from TFTP server

• Setup a TFTP server
• Put the firmware binary images MLO and u-boot.img in the root directory of the TFTP server
• Setup U-Boot networking:

for dynamic IP configuration:

# dhcp

or for static IP configuration:

# setenv ipaddr <ip address>
# setenv serverip <server ip>

• Download the SPL binary into memory:

# tftp 80a00000 MLO

• Download the U-Boot binary into memory:

# tftp 80100000 u-boot.img

• Proceed to Flashing images section

Flashing images

• Erase the on-board NAND flash for SPL image:

# nand erase 0 80000

• Write the SPL image into the on-board NAND flash:

# nand write 80a00000 0 20000;

• Erase the on-board NAND flash for U-Boot image:

# nand erase 200000 80000 

• Write the U-Boot image into the on-board NAND flash:

# nand write 80100000 200000 80000;

• Remove the micro SD card from the micro SD socket.
• Reset the CM-T335 evaluation platform.

See also

• CM-T335: U-Boot: Firmware Overview
• U-Boot quick reference
• U-Boot images
• Getting started with Linux on CM-T335
• U-Boot documentation
• SD/MMC format for OMAP3 boot