Re: [PATCH] ARM: /proc/cpuinfo: Use DT machine name when possible

[Pavel Machek <pavel@ucw.cz>]

On Wed 2014-06-18 20:59:08, Russell King - ARM Linux wrote:
> On Wed, Jun 18, 2014 at 09:09:58PM +0200, Pali Rohár wrote:
> > On Wednesday 18 June 2014 21:01:09 Russell King - ARM Linux 
> > wrote:
> > > On Wed, Jun 18, 2014 at 06:54:24PM +0200, Pali Rohár wrote:
> > > > Machine name from board description is some generic name on
> > > > DT kernel. DT provides machine name property which is
> > > > specific for board, so use it instead generic one when
> > > > possible.
> > > 
> > > http://archive.arm.linux.org.uk/lurker/message/20130726.132850
> > > .53d47576.en.html
> > > 
> > > "If userspace wants to get at the DT information about a
> > > platform, we already have ways that can happen already - we
> > > export the DT stuff so that kexec's tools can get at it."
> > 
> > Userspace application does not know that kernel using DT. And 
> > also it does not want to get DT information. Only board/machine 
> > name. So existing applications stop working after migration to 
> > DT. And because legacy board boot code (without DT) is going to 
> > be removed for ARM in near future this will permanently break 
> > existing applications.
> 
> We're already breaking the userspace API through moving to DT, because
> all the device names in /sys/devices are changing.  Userspace is going
> to have to cope with change as we move towards DT.  This is just
> another aspect of moving towards DT, and one which userspace is going
> to have to deal with.

You don't _have_ to break /proc/cpuinfo.  No, "DT breaks stuff" should
not be reason to "break more stuff".  (Actually, I'm not aware of
anything DT would have to break.)

									Pavel
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