diff mbox series

[2/3] ARM: dts: motorola-mapphone: Configure lower temperature passive cooling

Message ID 20201230084232.19221-2-tony@atomide.com (mailing list archive)
State New
Headers show
Series [1/3] ARM: dts: Configure missing thermal interrupt for 4430 | expand

Commit Message

Tony Lindgren Dec. 30, 2020, 8:42 a.m. UTC
The current cooling device temperature is too high at 100C as we have a
battery on the device right next to the SoC as pointed out by Carl Philipp
Klemm <philipp@uvos.xyz>. Let's configure the max temperature to 80C.

As we only have a tshut interrupt and no talert interrupt on 4430, we have
a passive cooling device configured for 4430. However, we want the poll
interval to be 10 seconds instead of 1 second for power management. The
value of 10 seconds seems like plenty of time to notice the temperature
increase above the 75C temperatures. Having the bandgap temperature change
seems to take several tens of seconds because of heat dissipation above
75C range as monitored with a full CPU load.

Cc: Carl Philipp Klemm <philipp@uvos.xyz>
Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Sebastian Reichel <sre@kernel.org>
Suggested-by: Carl Philipp Klemm <philipp@uvos.xyz>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 arch/arm/boot/dts/motorola-mapphone-common.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Pavel Machek Dec. 31, 2020, 2:33 p.m. UTC | #1
Hi!

> The current cooling device temperature is too high at 100C as we have a
> battery on the device right next to the SoC as pointed out by Carl Philipp
> Klemm <philipp@uvos.xyz>. Let's configure the max temperature to
> 80C.

Well... I am hitting even the 100C limit under load quite easily,
IIRC. I believe my Droid idles around 80C.... so this is likely to
make it... less useful.

Let me re-try and get some more numbers...

Best regards,
								Pavel
Pavel Machek Dec. 31, 2020, 6:53 p.m. UTC | #2
Hi!

> The current cooling device temperature is too high at 100C as we have a
> battery on the device right next to the SoC as pointed out by Carl Philipp
> Klemm <philipp@uvos.xyz>. Let's configure the max temperature to
> 80C.

It is very possible I don't have power management set up correctly, as
it breaks the modem.

(Additional problem is that shutdown does not work for me, it reboots
instead, so emergency poweroff won't do much good).

Shortly after bootup with kernel 5.9, I was using for motmdm debugging.

19:03, uptime 4min, CPU temp rose from 41 to 43C. Battery and board
are at 28C, 30C. Let me plug in the charger. It draws 350mA from USB.

19:20, CPU still at 43C, board and battery at 30C. That's way better
than I remember.

I ran "cat /dev/zero"; within seconds, CPU is at 52C. It also went
down to 45C rather quickly.

Lets try three instances of cat /dev/zero. Again, 52C in 20 seconds
and it slowly climbs to 58.5C.

Let's try ofono build. 60C rather quickly, then 62C and 65C. It takes
few minutes to climb to 68.5C.

But... this is way better then I remember. Let's hope temperatures
don't climb back during some other use. (Also... machine seems cooler
to touch.)

Best regards,
								Pavel
diff mbox series

Patch

diff --git a/arch/arm/boot/dts/motorola-mapphone-common.dtsi b/arch/arm/boot/dts/motorola-mapphone-common.dtsi
--- a/arch/arm/boot/dts/motorola-mapphone-common.dtsi
+++ b/arch/arm/boot/dts/motorola-mapphone-common.dtsi
@@ -192,6 +192,14 @@  backlight: backlight {
 	};
 };
 
+&cpu_thermal {
+	polling-delay = <10000>; /* milliseconds */
+};
+
+&cpu_alert0 {
+        temperature = <80000>; /* millicelsius */
+};
+
 &dss {
 	status = "okay";
 };