Re: [PATCH] enable RTAS /proc for PowerPC/CHRP platform

On Fri, Oct 20, 2006 at 03:56:37PM +1000, Benjamin Herrenschmidt wrote:

On Fri, 2006-10-20 at 07:44 +0200, Olaf Hering wrote:

quoted

On Fri, Oct 20, Benjamin Herrenschmidt wrote:

quoted

On Thu, 2006-10-19 at 09:03 +0200, Olaf Hering wrote:

quoted

On Thu, Oct 19, Benjamin Herrenschmidt wrote:

quoted

On Wed, 2006-10-18 at 09:38 +0200, Olaf Hering wrote:

quoted

On Wed, Oct 18, Michael Ellerman wrote:

quoted

But it's called '/proc/ppc64' right now on lots of machines, so you
can't go changing it.

if test -d /proc/ppc64 .. is a quick way to check wether the system is
64bit or not. Similar to if test -d /proc/iSeries ..

That's really ugly ! You really do that ? Gack...

What way should I use?

uname ? /proc/cpuinfo ? Whatever but not that.

uname can be faked with powerpc32 or setarch. grep POWER /proc/cpuinfo
might be an option. I think its only used in rpm preinstall scripts to
reject 64bit kernel on 32bit systems or the other way around.

grep POWER won't do good on 970 among others.

uname can be faked but why do you care ?

In fact, is somebody is faking it, maybe it's because they -want- your
scripts to think they are running on a 32 bits box....

I still think uname is the way to go.
 

Ben, would it make sense to add two informations to /proc/cpuinfo ?
It would be great to have a field there which will allow to check for the
kernel flavour to run, namely if the kernel/processor/whatever is running in
32bit or 64bit mode. The second field would be a generalized machine field,
or plateform or whatever, which would easily allow to differentiate between an
apple machine, a ibm chrp, a pegasos or other genesi product, etc. Without
necessarily having to maintain a huge amount of userlanf mappings from all
those different machine: fields, which all have CHRP, true, but no finer
grained informations, while we do have it in the kernel.

Friendly,

Sven Luther