Add TARGET_MACHINE to /etc/os-release

[Joseph Reynolds]

On 2018-11-29 17:03, Joseph Reynolds wrote:
>> Proposal to add TARGET_MACHINE to /etc/os-release.
> 

I've pushed this as gerrit review 16489.

https://gerrit.openbmc-project.xyz/#/c/openbmc/meta-phosphor/+/16489/

> I've updated the details to explain why the uname command is 
> unsatisfactory.
> 
>> 
>> In an OpenBMC image, the /etc/os-release file includes distro 
>> ("openbmc-phosphor") and version (as a git tag or commit).  It should 
>> also include the target machine (the kind of device the OpenBMC image 
>> is intended to control).  This is needed to be able to track the image 
>> back to its source code: the distro and version indicate the exact 
>> source code that was used, and the target says which Bitbake layer 
>> configuration within that source was used.
>> 
>> Specifically, the proposal is to enhance the generated /etc/os-release 
>> file with a new OS identification parameter like:
>>   OPENBMC_PHOSPHOR_TARGET_MACHINE="$MACHINE"
>> where MACHINE="romulus", for example.
>> 
>> All OpenBMC images should define this os-release parameter.
>> 
>> Proposed documentation for the new parameter: Indicates the kind of 
>> device the OpenBMC image is targeted to control.
>> 
>> ... tl;dr details follow ... snip ...
>> 
>> The MACHINE is set in 
>> openbmc/meta-COMPANY/meta-MACHINE/conf/local.conf.sample.  (This is 
>> where TEMPLATECONF points to.)
>> 
>> Note MACHINE is not guaranteed to be unique across all future OpenBMC 
>> layer configurations.  (That is, meta-A/meta-B/conf and 
>> meta-X/meta-Y/conf may inadvertently define the same machine name.) To 
>> guarantee uniqueness, an alternate design would be to use the 
>> TEMPLATECONF parameter as the machine name. (e.g., 
>> "meta-ibm/meta-romulus/conf").  In practice I expect the machine name 
>> will be sufficiently unique: as unique as different company's brand 
>> and model names.
>> 
>> The manual page for "os-release" recommends prefixing the parameter 
>> name with the distro name.  Ideas for alternate parameter names are 
>> welcome ("OBMC_TARGET_HARDWARE" anyone?).  See 
>> https://www.freedesktop.org/software/systemd/man/os-release.html.
>> 
>> The os-release file is generated by the os-release.bb and 
>> os-release.bbappend recipes.
> 
> The "uname" command options -m (machine) and -i (hardware platform)
> will continue to refer to the BMC and not its host.