Embedded module TQMa65xx - YOCTO Linux BSP documentation

⇒ Boot Device Issue

In the BSP Rev.0005 the bootdevice is selected by the UUID from the Uboot. This UUID comes from the built image (.wic). If the same image is written to eMMC and SD card, there is a UUID conflict because both devices have the same ID and the module does not boot reliably from the selected device.

Workaround

To change the UUID of a device (e.g. eMMC) the following linux command can be used:

root@tqma65xx:~# echo -e "x\n i\n 0x$(xxd -ps -l4 /dev/random)\n r\n w\n" | fdisk /dev/mmcblk0

this command sets the UUID of eMMC (mmcblk0) to a random value.

⇒ PRU Ethernet Issue

currently there is a restriction on the PRU Ethernet ports (X4, X5, X6, X7, X15, X16) regarding auto negotiation. For the time being, the PRU Ethernet interfaces can only establish a link with a direct connection. Using a switch between starter kit and remote station can cause problems and no link can be established.

PRU MAC addresses

The first PRU MAC address is located in an EEPROM (Bus 0, Dev 0x50) and is not yet read out automatically in BSP Rev.0005. For this reason the PRUs receive generic MAC addresses, which should be sufficient for testing purposes.

To read the content of the EEPROM, use the following uboot command:

=> i2c md 0x57 0x00 0x80

The PRU MAC addresses can be set manually in the UBoot environment if they are needed. Here the example for the MAC address 00:D0:93:11:22:33 in the EEPROM:

=> setenv eth1addr 00:d0:93:11:22:33
=> setenv eth2addr 00:d0:93:11:22:34
=> setenv eth3addr 00:d0:93:11:22:35
=> setenv eth4addr 00:d0:93:11:22:36
=> setenv eth5addr 00:d0:93:11:22:37
=> setenv eth6addr 00:d0:93:11:22:38

The variables will be lost after a restart. The command “saveenv” can be used to save and preserve the variables.