Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load

From: Marek Szyprowski
Date: Thu Feb 18 2016 - 04:59:40 EST


Hello,

On 2016-02-18 05:42, Krzysztof Kozlowski wrote:
On 18.02.2016 11:36, Viresh Kumar wrote:
BTW, I found the issue. The order of trip points in DT:
thermal_zone0/trip_point_0_hyst:5000
thermal_zone0/trip_point_0_temp:50000
thermal_zone0/trip_point_0_type:active
thermal_zone0/trip_point_1_hyst:5000
thermal_zone0/trip_point_1_temp:60000
thermal_zone0/trip_point_1_type:active
thermal_zone0/trip_point_2_hyst:5000
thermal_zone0/trip_point_2_temp:70000
thermal_zone0/trip_point_2_type:active
thermal_zone0/trip_point_3_hyst:0
thermal_zone0/trip_point_3_temp:120000 <---- this should be last one!
thermal_zone0/trip_point_3_type:critical
thermal_zone0/trip_point_4_hyst:5000
thermal_zone0/trip_point_4_temp:90000
thermal_zone0/trip_point_4_type:passive
thermal_zone0/trip_point_5_hyst:5000
thermal_zone0/trip_point_5_temp:110000
thermal_zone0/trip_point_5_type:passive

After fixing the order in DT, the cpu cooler starts working.
Ahh, nice.
Damn, not entirely. I almost fried my Odroid (it survived 130 degrees of
C)... The TMU supports only 4 trip points, so when I added two new trip
points and reordered them... the last two (including critical) was not
receiving interrupts.

Polling mode is needed. I'll sent some patches soon...

Instead of polling the driver should simply use some dynamic window for
the nearest temperature ranges and reconfigure it when interrupt of occurs.

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland