Re: therm_pm72 units, interface

["Michel Dänzer" <michel@daenzer.net>]

On Sam, 2013-07-20 at 23:33 +0300, Aaro Koskinen wrote:
> Hi,
>=20
> On Sat, Jul 20, 2013 at 09:16:49AM +1000, Benjamin Herrenschmidt wrote:
> > On Fri, 2013-07-19 at 20:43 +0300, Aaro Koskinen wrote:
> > > I booted a Xserve today with 3.11-rc1, and noticed the noise is comin=
g
> > > from slots-fan (PCI fan?) which is always 99%, although the slots-tem=
p is
> > > just 33. Is it on purpose the rm31 slots PID params are totally diffe=
rent
> > > from therm_pm72 slots params? It seems like they have been copied fro=
m
> > > pm72 "drive bay" PID params instead.
> >=20
> > Could be my mistake. What happens if you change them to match the old c=
ode ?
>=20
> I tried the change below (use SLOTS_PID_* values from therm_pm72.h),
> and the noise level is considerably lower. The slots-fan stays at 19%,
> and slots-temp rises to 42'C but not higher after running couple of hours=
.
>=20
> diff --git a/drivers/macintosh/windfarm_rm31.c b/drivers/macintosh/windfa=
rm_rm31.c
> index 0b9a79b..82fc86a 100644
> --- a/drivers/macintosh/windfarm_rm31.c
> +++ b/drivers/macintosh/windfarm_rm31.c
> @@ -439,15 +439,15 @@ static void backside_setup_pid(void)
> =20
>  /* Slots fan */
>  static const struct wf_pid_param slots_param =3D {
> -	.interval	=3D 5,
> -	.history_len	=3D 2,
> -	.gd		=3D 30 << 20,
> -	.gp		=3D 5 << 20,
> -	.gr		=3D 0,
> -	.itarget	=3D 40 << 16,
> -	.additive	=3D 1,
> -	.min		=3D 300,
> -	.max		=3D 4000,
> +	.interval	=3D 1,
> +	.history_len	=3D 20,
> +	.gd		=3D 0,
> +	.gp		=3D 0,
> +	.gr		=3D 0x00100000,
> +	.itarget	=3D 3200000,
> +	.additive	=3D 0,
> +	.min		=3D 20,
> +	.max		=3D 100,
>  };
> =20
>  static void slots_fan_tick(void)

Could a similar change fix the same problem on desktop G5s? The same
values for slots_param in windfarm_pm112.c don't help, unfortunately.


--=20
Earthling Michel D=C3=A4nzer           |                   http://www.amd.c=
om
Libre software enthusiast         |          Debian, X and DRI developer