Subject: Appended DTB files for multi-machine kernels

From: [email-masked] (Daniel Mack)
Date: Fri, 26 Jul 2013 18:13:08 +0200

On 04.07.2013 19:28, Nicolas Pitre wrote:
> On Thu, 4 Jul 2013, Daniel Mack wrote:
>> In short, devices that have been deployed in quantities come in three
>> hardware variants, which all boot with a unique machine-id. We ship
>> kernel images that have board support for all three machine types, and
>> do minor fixups to platform data of some drivers at runtime, depending
>> on the board revision number (passed in via ATAGs).
>>

> What you describe above more or less fits the definition of what I 
> called the "impedance matcher".  However it doesn't need to be part of 
> the kernel at all.  But you should make it into a separate binary.
> 
> Please have a look at the bottom of this post for a more comprehensive 
> description: http://article.gmane.org/gmane.linux.ports.arm.kernel/242929

FWIW, I gave that approach a try today for a PXA based hardware
platform, and in fact it seems to work very well. Thanks again for
sharing the idea.

In case anyone is interested, the repository is here:

  https://github.com/zonque/pxa-impedance-matcher

As the README says, it's completely specific to my use case, but maybe
anyone can use the code base to spin a different version for a different
board.

Daniel