Subject: Re: MIPS power management support ??
To: Toru Nishimura <>
From: Jason R Thorpe <>
List: port-cobalt
Date: 05/29/2001 10:56:57
On Tue, May 29, 2001 at 10:08:12AM +0900, Toru Nishimura wrote:

 > "Andre" <> wrote;
 > > After trying out netbsd 1.5 (the NOSCSI version of the kernel) on
 > > a Qube2, I am concerned that netbsd might not be the best OS to
 > > help ensure a long and reliable lifetime for the cpu....
 > >
 > > Under Linux, the cpu ran cool to the touch for most of the time,
 > > but with netbsd it seems to get _very_ hot, even when the system
 > > is lightly loaded.
 > Cosuming power is concern, however, dissipated heat should not destroy
 > the QED processor.
 > > Is power management really missing from netbsd ? or do I simply
 > > need to try a different version kernel ??
 > NetBSD/cobalt does not have it inside.  MIPS processor manufactures
 > implemented power saving instructions in incompatible ways.
 > MIPS/hpcmips for WinCE devices uses its own power saving hook when the
 > NEC Vr process is idle.  So, it should not be hard to add QED specific
 > power saving stuff mimicking Vr.

I just implemented this and tested it on my Algorithmics P-5064.  The
QED RM5260 CPU in it now runs cool to the touch (in fact, about as cool
as when the entire machine is powered off).  Heh, the Ethernet chip now
runs hotter than the CPU :-)

It's committed to -current.

        -- Jason R. Thorpe <>