Fan control for new PowerMac G5 2.7GHz machines?

[Benjamin Herrenschmidt]

On Fri, 2005-08-05 at 16:52 -0700, Brian D. Carlstrom wrote:
> Benjamin Herrenschmidt writes:
>  > > i2c /dev entries driver
>  > > /u3 at 0,f8000000/i2c at f8001000: Missing interrupt or address !
>  > > 
>  > > In therm_pm72_attach() it hits 'Found K2', but u3_0 and u3_1 
>  > > are never set, so start_control_loops() is never called.
>  > > 
>  > > I'll look at it more when I have some time.
>  > 
>  > Ah yes, this is indeed the problem ! There is a bug in Apple device tree
>  > on these machines that is breaking Linux. I should have a workaround
>  > upstream, but for some reason, it seems it's not working for you.
> 
> Well, I have good news and bad news. I switched from the patched YDL
> 2.6.10-1 to linux-stable 2.6.12.3 to debug the fan issue. 

The problem is realted to the device-tree fixup code as I posted.

> The good news is that my fans control now works. Since Geoff is having
> problems, I'll include my DBG output from therm_pm72 below. For me it
> is reporting "found U3-1, attaching FCU" and not "Found K2".
> 
> The bad news is that ybin is having trouble:
> 
>     # ybin
>     ofpath: /proc/device-tree is broken.  Do not use BootX to boot, use yaboot.
>     ofpath: The yaboot HOWTO can be found here: http://www.alaska.net/~erbenson/doc
>     ybin: Unable to find OpenFirmware path for boot=/dev/sda2
>     ybin: Please add ofboot=<path> where <path> is the OpenFirmware path to /dev/sda2 to /etc/yaboot.conf
> 
> I've heard a newer yaboot might fix this but for now I just booted to my
> old kernel to update yaboot.conf.

Just edit "ofpath" (it's a shell script) and simply remove the test that
trigger this error, it's bogus.

Ben.