Digilent Embedded Linux - Manual (Page 15)

Using Zynq with Linux
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For more detailed information about kernel parameters, please refer to kernel-parameter.txt
under Documentation in the Linux kernel source.
File System Customization
The Linux Kernel is a standalone program that manages system resources and provides a
standardized Application Programming Interface (API) for user applications to interact with hardware.
The Linux Kernel requires a file system to become a computer system. Otherwise, the kernel cannot
interact with the human and will panic immediately. The Appendix: How to Debug the Linux Kernel
discusses procedures for dealing with panics.
Configure Root File System
You must specify a root file system in the kernel arguments with:
root=/dev/ram rw initrd=0x800000,8M rootfstype=ext4
As explained in the previous section, it assigns the root file system to the ramdisk that is loaded into
Memory (/dev/ram) at 0x800000. If you want to boot a system like the Linaro Desktop from partition
2 on your SD card, then change the previous argument to:
root=/dev/mmcblk0p2 rw rootfstype=ext4
This line points the root file system to the block device /dev/mmcblk0p2 that is the second partition
on the SD card. For detailed instructions about how to format your SD card and install Linaro, please
refer to the Getting Started With Embedded Linux guides available on Digilent Website, Embedded
Linux Page.
Boot with Ramdisk
The ramdisk image is available at Digilent Website, Embedded Linux Page as well.
To customize the ramdisk, you need to decompress it first with the command
$ gzip -d ramdisk8M.image.gz
The command will remove the zipped file and substitute it with a decompressed file named
ramdisk8M.image.
Then you can mount the ramdisk8M.image to a directory in your file system with:
$ sudo mount ramdisk8M.image /mnt/ramdisk -o loop
You can make changes to the file system directly by reading and writing the /mnt/ramdisk folder.
After you finished the customization, unmount ramdisk8M.image with the command:
$ sudo umount /mnt/ramdisk
Zip the file up again with the command: