powerpc/windfarm: Fix noisy slots-fan on Xserve (rm31)

slots-fan on G5 Xserve is always running at full speed with windfarm_rm31
driver, resulting in a very high acoustic noise level. It seems the fan
parameters are incorrect, and have been copied from the Drive Bay fan
(RPM, not present on rm31) of the legacy therm_pm72 driver. This patch
changes the parameters to match the Slots fan (PWM) of therm_pm72. With
the patch, slots-fan speed drops from 99% to 19% during normal use,
and slots-temp settle to ~42'C.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
CC: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Aaro Koskinen 2013-07-21 03:30:11 +03:00 committed by Benjamin Herrenschmidt
parent 3be7db6ab4
commit fe956a1d40

View file

@ -439,15 +439,15 @@ static void backside_setup_pid(void)
/* Slots fan */
static const struct wf_pid_param slots_param = {
.interval = 5,
.history_len = 2,
.gd = 30 << 20,
.gp = 5 << 20,
.gr = 0,
.itarget = 40 << 16,
.additive = 1,
.min = 300,
.max = 4000,
.interval = 1,
.history_len = 20,
.gd = 0,
.gp = 0,
.gr = 0x00100000,
.itarget = 3200000,
.additive = 0,
.min = 20,
.max = 100,
};
static void slots_fan_tick(void)