Creating a bootable microSD card
The Overo board will boot directly from a properly prepared microSD card.
This section will outline how to partition and format a bootable microSD card.
In order to create a bootable microSD compatible with the OMAP3 boot ROM, the SDK automatically format the SD and save the necessary images in the correct partitions.
This example will show the steps for setting up a 2GB microSD card.
Verify your SD CARD is working
First insert your card into your development machine's flash card slot. You may need to use a microSD to SD card adaptor to fit your slot. You can use 'mount' or 'df' to see where the card mounts on your machine.
$ df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda1 234521212 35058568 187549648 16% /
none 1009920 372 1009548 1% /dev
none 1014140 1940 1012200 1% /dev/shm
none 1014140 124 1014016 1% /var/run
none 1014140 0 1014140 0% /var/lock
none 1014140 0 1014140 0% /lib/init/rw
/dev/sdd1 39497 4916 34582 13% /media/boot
/dev/sdd2 1857948 93928 1669640 6% /media/rootfs
Set the correct options installer
The option (/dev/sdd) SD device could vary , and its depends on each PC and SD card. The option (/dev/ttyUSB0) Serial port for target communication allow the pc to have a console running on the target. The options Create and format the SD partitions (FAT and Ext3) , allow the SDK format the SD card and create two partitions A FAT partition: I'll have the bootloader , xloader and kernel images
A linux partition (Ext3) to
[*] Create and format the SD partitions (FAT and Ext3)
Bootloader destination (Flash) --->
Kernel destination (SD) --->
File System destination (SD) --->
There are three files required on the first (FAT) partition to boot your Overo:
MLO:
The boot-loader loader - this small program is loaded into the OMAP3 processor's static RAM. It does some minimal configuration of system memory and io pins and then loads the second file.
u-boot.bin
The boot loader image At a minimum an embedded bootloader provides the following features:
- Initializing the hardware, especially the memory controller.
- Providing boot parameters for the Linux kernel.
- Starting the Linux kernel
uImage:
The linux kernel
You can build these yourself and download pre-built images. or use the SDK installer. It is important that these three files have precisely these names. , but the SDK installer automatically set those names.
Prefilling SD card with 0xFF
You may want to fill the SD card with 0xFF first so that an image made by copying the entire SD card compresses better.
SD_DEV=/dev/sdd
tr "\000" "\377" < /dev/zero | sudo dd bs=16M of=${SD_DEV}
Running the SDK installer
The SD card must be on on the SD Card Reader Be sure u-boot is running on port /dev/ttyUSB0 and none process (like minicom) is using it
on the terminal run the following command
make install
The SDK installer will automatically set all the environment on the u-boot and save the images to the SD Card this is the log derived from the installation
$ make install
------------------------------------------------------------------------------------------------------
Ridgerun Linux SDK
Board configuration: Gumstix Overo Board
Installation system of uboot images over TFTP for host 1500
Please be sure u-boot is running on port /dev/ttyUSB0 and none process (like minicom) is using it
u-boot port /dev/ttyUSB0
Performing handshake with u-boot...done.
Trying to identify NAND block size... detected 0x20000
Creating SD partitions on the device /dev/sdd...
a) Boot partition for Bootloader and kernel
b) Root File System partition
Unmounting the existent partitons...
sudo umount /dev/sdd'1'
sudo umount /dev/sdd'2'
Creating the partitions...
sudo fdisk /dev/sdd < .sd
Formating partitions...
sudo mkfs.vfat -F 32 /dev/sdd'1' -n boot
sudo mkfs.ext3 /dev/sdd'2' -L rootfs
sudo fsck.ext3 /dev/sdd'2'
e2fsck 1.41.11 (14-Mar-2010)
fsck.ext3: Superblock invalid, trying backup blocks...
fsck.ext3: Bad magic number in super-block while trying to open /dev/sdd
The superblock could not be read or does not describe a correct ext2
filesystem. If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>
The partition table is:
Disk /dev/sdd: 1977 MB, 1977614336 bytes
255 heads, 63 sectors/track, 240 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x6308582a
Device Boot Start End Blocks Id System
/dev/sdd1 * 1 5 40131 c W95 FAT32 (LBA)
/dev/sdd2 6 240 1887637+ 83 Linux
Verifying if kernel needs to be installed...
Flashing Kernel image to SD...
Mounting boot partition...
sudo mount /dev/sdd'1' images/boot
Copying the kernel into the SD...
cp $(DEVDIR)/images/kernel.uImage $(DEVDIR)/images/boot/
Unmounting the boot partition...
sudo umount $(DEVDIR)images/boot
Saving new kernel load address...
Uboot <= setenv kernelloadaddr 0x82000000
Verifying if file system needs to be installed...
Flashing File System to SD...
Unmounting rootfs partition...
sudo umount /dev/sdd'2'
Formating rootfs partition...
sudo mkfs.ext3 /dev/sdd'2' -L rootfs
Mounting rootfs partition...
sudo mount -t ext3 /dev/sdd'2' images/rootfs
Copying the File System into the SD...
cd fs/fs && find . | sudo cpio -pdum images/rootfs/
201312 blocks
Unmounting the rootfs partition...
sudo umount /dev/sdd'2'
sudo fsck.ext3 /dev/sdd'2'
e2fsck 1.41.11 (14-Mar-2010)
e2fsck: need terminal for interactive repairs
Verifying if kernel command line needs to be installed...
Kernel command line doesn't need to be installed
Verifying if the boot command needs to be installed...
Uboot <= setenv bootcmd 'mmc init ; fatload mmc 0 \${kernelloadaddr} kernel.uImage ; bootm \${kernelloadaddr}'
Uboot <= setenv autostart yes
Uboot <= saveenv
Reboot the board with the SD
After all the process , reboot the target with the SD an the check the installation works properly