Subject: Re: [PATCH 5/7] powerpc/85xx: Add power management support for MPC85xxMDS boards

From: Anton Vorontsov <[email-masked]>
Date: Thu, 5 Nov 2009 17:08:38 +0300

On Thu, Nov 05, 2009 at 08:02:44AM -0600, Kumar Gala wrote:
[...]
> >diff --git a/arch/powerpc/boot/dts/mpc8568mds.dts b/arch/powerpc/
> >boot/dts/mpc8568mds.dts
> >index 00c2bbd..6d892ba 100644
> >--- a/arch/powerpc/boot/dts/mpc8568mds.dts
> >+++ b/arch/powerpc/boot/dts/mpc8568mds.dts
> >@@ -40,6 +40,8 @@
> >			i-cache-line-size = <32>;	// 32 bytes
> >			d-cache-size = <0x8000>;		// L1, 32K
> >			i-cache-size = <0x8000>;		// L1, 32K
> >+			sleep = <&pmc 0x00008000	// core
> >+				 &pmc 0x00004000>;	// timebase
> >
> >Just so I'm clear this is the devdisr bit position?
> 
> Also where in the code do we use this?  I'm not seeing it.

We don't use it (yet). The per-device power management is not yet
implemented. It is relatively easy to do on 83xx, but on 85xx there
is a restriction: we can't re-enable the device after we disable it,
i.e. POR sequence is needed. Though, we may want to disable all
'unused' (say echo 1 > /sys/devices/.../permanently_disable) to save
some power.

Thanks,

-- 
Anton Vorontsov
email: [email-masked]
irc://irc.freenode.net/bd2