plugwash
Forum Moderator
Forum Moderator
Posts: 3225
Joined: Wed Dec 28, 2011 11:45 pm

Has there been a major change in the firmware and/or dtbs?

Thu Jun 01, 2017 6:09 pm

I'm trying to update the debian-style kernel/firmware packages in raspbian (where we ship kernel and firmware/dtbs seperately) but i'm finding that there seem to be major compatibility issues.

Trying to boot a 4.4 kernel with the new firmware/dtbs hangs at the rainbow screen.
Trying to boot a 4.9 kernel with the old firmware/dtbs appears to start booting but fail to mount the rootfs for some reason.

Has there been a major change in the kernel to firmware interface and/or the dtbs between 4.4 and 4.9 ? Is there any way to make a firmware/dtbs package that works with both kernels?

plugwash
Forum Moderator
Forum Moderator
Posts: 3225
Joined: Wed Dec 28, 2011 11:45 pm

Re: Has there been a major change in the firmware and/or dtb

Thu Jun 01, 2017 7:04 pm

Further testing shows it is the dtbs that are the issue.

PhilE
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 1439
Joined: Mon Sep 29, 2014 1:07 pm
Location: Cambridge

Re: Has there been a major change in the firmware and/or dtb

Fri Jun 02, 2017 8:45 am

Yes, there has been a major change. Between 4.4 and 4.9 we switched to using the upstream bcm2835 board support library, and several other upstream drivers. Although we try to preserve backwards compatibility, avoiding breaking changes between kernel and firmware versions where possible, the expectation is that the dtbs are treated as part of the kernel package.

plugwash
Forum Moderator
Forum Moderator
Posts: 3225
Joined: Wed Dec 28, 2011 11:45 pm

Re: Has there been a major change in the firmware and/or dtb

Sat Jun 10, 2017 1:33 pm

Turns out a relatively small change to the dtbs will make both kernels boot. My patch script is at

https://github.com/raspbian-packages/ra ... /fixupdtbs

User avatar
Gavinmc42
Posts: 1607
Joined: Wed Aug 28, 2013 3:31 am

Re: Has there been a major change in the firmware and/or dtb

Sun Jun 11, 2017 1:32 am

About time.
This drove me nuts, I have been sticking to 4.4 and not doing update/upgrade for field units.
Updating/Upgrading to 4.9 is for bleeding edge users, sometimes it works, sometimes it harikari's.

Any idea when 4.9 becomes official?
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

runboy93
Posts: 310
Joined: Tue Feb 28, 2017 1:17 pm
Location: Finland

Re: Has there been a major change in the firmware and/or dtb

Sun Jun 11, 2017 9:04 am

Gavinmc42 wrote:About time.
This drove me nuts, I have been sticking to 4.4 and not doing update/upgrade for field units.
Updating/Upgrading to 4.9 is for bleeding edge users, sometimes it works, sometimes it harikari's.

Any idea when 4.9 becomes official?
If you have updated your Raspbian, there should be kernel 4.9.24 on your system.
Aluminum case for Raspberry Pi 3
https://goo.gl/DQT3nc

RPi 3 tweaks by runboy93
https://goo.gl/MM5FmR

Return to “Linux Kernel”

Who is online

Users browsing this forum: No registered users and 1 guest