Booting & Load Understanding for R2

Hello, I would like to understand how can we make R2 boot from a USB/SDCard. I am asking this to try and built Manjaro Linux with and without Desktop Environment.

  • Do we need a uboot in the media or the SPI have its own uboot which have multi-boot option?
  • Partitions Need in the Media to boot?
  • If Multiple partition then, which files are needed in the Boot partition?

For r2 i have written this here:

For sd you need preloader,uboot and 2 additional bootheaders…partitions are used afterwards…by default 1 fat (which holds kernel and uboot-config) and 1 ext4 as rootfs…you can also create more partitions

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Well I was just reading the same link as this is there in the dev link. :smiley:Thanks for such s good documentation. I am going through the files, I will do some test runs without the device until it arrives. Also I will have to follow your kernel branches to compile, as I dont think there is any mainline support for R2.

Thanks for your quick response.

for r2 there is mainline support,but some features are not available/working without my modifications such as hdmi,internal wifi,poweroff (maybe in 5.4),…

Btw which dev-link do you mean?

Oh ok, Thats the same with most of the SBC.

The same Link which you provided is there in I found that link there with a special thanks to you.

I tried flashing openwrt image and it made 2 partition in my usb stick boot partition having uEnv and uImage file while root partition having rootfs

But when i flashed ubuntu image it only created a single partition with the above mentioned file.

I will try now images and understand how its built.

How did you flashed ubuntu-image,imho all ubuntu/debian-images create the fat+ext partitions. most Openwrt-images (except lexa2-version) does not create partitions. cannot boot r2 from usb. At least till uboot it needs to be on sd/emmc. Uboot currently does not support usb,so you need to load kernel also from sd/emmc/sata and only rootfs can be on usb

I downloaded openwrt from Download wiki page and flashed it on usb using etcher. It created 2 partition.

Ok thanks for the information about usb ill use sd card when the device is with me.

And yes I know the fat for boot n ext4 for rootfs but i was shocked to see ubuntu 9gb image turned into few mbs which only had boot files and nothing in rootfs :frowning:

And the download images are very fragmented online for R2.

Can you guide me to the latest working img’s please.


My images are on gdrive :slight_smile:

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Thanks for the link. There the Ubuntu buster img flashed correctly but in boot partition I see the main files inside multiple directories. Is that fine? or those files should be in the root for the boot partition?

Screenshot below

this is right for boot-partition (#1), because uboot looks in this structure

as official images + uboot are using this structure, is used it also for my uboot + images

you should have also root-partition (#2)

I understood the boot Partition now but have a doubt when I was going through this thread so I asked something there.