OMAP Wireless Connectivity AM37x Software Upgrade

Preparing an SD Card

The EVM box contains an SD card that is ready-to-use, provided with the up-to-date software for running WLAN and BT demos. However, whenever software upgrade is required, the SD card must be upgraded according to the instructions provided in this section.

To prepare an SD card suitable to boot from, you need to have the following files:

• MLO - addition for u-boot to load from SD card
• u-boot.bin - u-boot Linux loader binary
• uImage - image of Linux kernel to be loaded by u-boot
• root file system that will be mounted by board

Steps to be followed to generate a bootable SD card:

1. Enter the SD and check what is the name Linux system provided to the "new device". For example: in Ubuntu distribution running 'sudo fdisk -l' will detail the device-names provided to each disk by the system. Assume that the inserted card got the name /dev/sdc.
2. Partitioning

• Format a card as follows: dd if=/dev/zero of=/dev/sdc bs=1024 count=1024
• Run sudo fdisk /dev/sdc

   add a new partion (option n)
   make a primary partition (option p)
   select the partition number as 1
   select the first cylinder as 1 (the default gets taken on pressing enter) and last cylinder as '''+100M'''

   add a new partion (option n)
   make a primary partition (option p)
   select the partition number as 2
   select the first cylinder as 3271 (the default gets taken on pressing enter) and select the last cylinder as default value by pressing enter.
   Start writing and exit (option w)

3. Making file systems

• make first partition as FAT with label 'boot': sudo mkfs.vfat -F 32 -n boot /dev/sdc1
• make second partition as ext3 with label 'rootfs': sudo mkfs.ext3 -L rootfs /dev/sdc2

4. Coping files

• First partion will contain boot files: MLO, u-boot and uImage. The order of the files being copied is significant:

mount /dev/sdc1 /mnt
cp MLO /mnt/MLO
cp u-boot.bin /mnt/u-boot.bin
cp uImage /mnt/uImage
umount /dev/sdc1

• Second partion will contain root file system to be mounted by Linux on a board:

mount /dev/sdc2 /mnt
sudo tar zxvf some-rootfs.tar.gz -C /mnt
chmod 755 /mnt
umount /dev/sdc2

Now the SD card is ready.