[U-Boot] Environment storage format stability

[U-Boot] Environment storage format stability

[Kristian Amlie]

I have a question about the format of the environment when stored on
persistent storage: Is this format considered stable?

The reason I'm asking is whether it is a reasonable assumption that
upgraded user space tools (fw_setenv and fw_printenv) will agree on the
format with an older boot loader. The user space tools may be upgraded
as part of a rootfs update, but the boot loader typically will not.

-- 
Kristian

[U-Boot] Environment storage format stability

[Wolfgang Denk]

Dear Kristian,

In message <7f7560f1-5b05-1f0c-8bf0-fd0458f9d3fe@mender.io> you wrote:
> I have a question about the format of the environment when stored on
> persistent storage: Is this format considered stable?

Yes, it is.  It has never been changed since it has been invented in
the first days of this project, when it was still sailing under the
name PPCboot, and there are no plans or discussions to change it,
either.

> The reason I'm asking is whether it is a reasonable assumption that
> upgraded user space tools (fw_setenv and fw_printenv) will agree on the
> format with an older boot loader. The user space tools may be upgraded
> as part of a rootfs update, but the boot loader typically will not.

As of now, you can still read the environment of a 16 year old PPCBoot
:-)

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
For every complex problem, there is a solution that is simple,  neat,
and wrong.                                               - Mark Twain

[U-Boot] Environment storage format stability

[Kristian Amlie]

On 15/12/16 17:21, Wolfgang Denk wrote:
> Dear Kristian,
> 
> In message <7f7560f1-5b05-1f0c-8bf0-fd0458f9d3fe@mender.io> you wrote:
>> I have a question about the format of the environment when stored on
>> persistent storage: Is this format considered stable?
> 
> Yes, it is.  It has never been changed since it has been invented in
> the first days of this project, when it was still sailing under the
> name PPCboot, and there are no plans or discussions to change it,
> either.
> 
>> The reason I'm asking is whether it is a reasonable assumption that
>> upgraded user space tools (fw_setenv and fw_printenv) will agree on the
>> format with an older boot loader. The user space tools may be upgraded
>> as part of a rootfs update, but the boot loader typically will not.
> 
> As of now, you can still read the environment of a 16 year old PPCBoot
> :-)

Perfect, thanks! :-)

-- 
Kristian