Picking ARM or x86 to boot from

Question

I currently have a raspberry pi, and am using my sd card to boot into linux for on-the-go access. However, the sd card boots into an ubuntu x86 version, not ARM. I saw the tutorial on how to flash the sd card for a raspberry pi, but I was curious if there is a way to pick which OS with specific architecture to boot off of. Is there a way to choose whichever system you would like to boot from?

Answer 1

Your SD card currently allow you to boot on ubuntu x86. You just want to add the ability to boot on your RPi. This totally depends on the ability of the RPi. I can't find complete documentation on RPi processor (this is why I don't like RPi (and Broadcom)), but, according to some online documentation , the RPi boots on FAT32. Your PC is probably also able to boot on a FAT32-formated SD card.

So, if your SD card format fits RPi requirements, you may put your bootable ubuntu x86 and a RPi bootloader on the same SD card partition. RPi is baremetal ARM, so you may put anything you want in your bootloader, including looking for your kernel on FAT32 on SD card with any name you want. It is therefore possible to add your ARM bootloader, your ARM kernel, and an ARM ramfs on your SD card without interfering with the x86 related files. You may then add a partition on your SD card to put your ARM binaries (some will use the same name as the x86, such as bash or startx , and should not be put on the same location than x86 ones, to avoid conflicts), and share data partitions between x86 and ARM OS.