[RFC PATCHv2 1/2] Export SoC info through sysfs

Arnd Bergmann arnd at arndb.de
Thu Apr 7 19:19:10 EDT 2011

On Friday 08 April 2011, Ryan Mallon wrote:
>>>>> /sys/devices/soc/${NAME}/
>>>>> /sys/devices/platform/soc${NUMBER}/
>>>> I prefer the second format here since the path is always the same which
>>>> makes it easier to write parsing tools. The name should be an entry in
>>>> the directory rather than the name of the directory itself.

In the first case, we would ensure that every directory under /sys/devices/soc
is an SOC device, so you would not need to parse the name at all, which is
even simpler. I'm open to other arguments either way, but I think this
one is not particularly important.

> > That would mean two separate instances of Linux, just like two systems.  
> > SMP across multiple SOCs doesn't make much sense, and I don't think they 
> > are likely to be designed for that ability either.
> So we probably don't need the ability to have multiple SoC directories
> under sysfs then?

There are systems that have multiple ones, they are just not as common.

> For the other part of the question, do you think it makes sense for the
> CPU's to be child devices of the SoC (and for the CPU devices to be
> potentially symlinked from the SoC directory)?

No, the CPUs are children of /sys/devices/system, and we should not change
that. Symlinks sound like a good idea though.


More information about the linux-arm-kernel mailing list