VAR-SOM-AM33 boot via-ethernet

From Variscite Wiki

Boot over Network (Ethernet)

NOTE:
When setting a MAC address please ensure that the LS-bit of the 1st byte is not 1 i.e. when setting the MAC address: y in xy:ab:cd:ef:gh:jk has to be an even number.

            For more info this refer to the wiki page http://en.wikipedia.org/wiki/MAC_address.

When kernel image and root file-system are fetched from a TFTP/NFS server:

  • Ensure that the SOM is connected to network with DHCP and TFTP server set up
  • If the TFTP server supports negotiation between client and server, Disable it
  • Copy 'uImage' kernel image to TFTP server's root directory.
  • Set 'ethaddr' U-Boot environment variable with proper ethernet address in format 'xx:xx:xx:xx:xx:xx' (replace 'xx' with proper hexadecimal values)
  • Setup NFS server and export one of the provided pre-build root file-system
  • Execute following commands at U-Boot prompt. Assuming kernel image name as 'uImage':
U-Boot # setenv fdtfile '<var-som-am33.dtb filename on TFTP>'
U-Boot # setenv bootfile <zImage filename on TFTP>
U-Boot # setenv netargs 'setenv bootargs console=${console} ${optargs} root=/dev/nfs nfsroot=${serverip}:${rootpath},${nfsopts} rw ip=dhcp vram=50M'
U-Boot # setenv serverip <Server IP address>
U-Boot # setenv rootpath '<Path of the exported root file-system on the NFS server>'
U-Boot # run netboot

Note, that the roopath parameter should be the directory of the extracted rootfs image, as explained above in section Building the VAR-SOM-AM33 Yocto image extracting the image to '/home/user/yocto_varsomam33/rootfs/'.