Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1336086

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

From Krzysztof Kozlowski <k.kozlowski@samsung.com>
Newsgroups linux.kernel
Subject [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load
Date 2016-02-17 08:00 +0100
Message-ID <r34fE-2FN-11@gated-at.bofh.it> (permalink)
References <r34fD-2FN-7@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


After adding cpufreq-dt support to Exynos542x, the Odroid XU3-Lite can
be easily overheated when launching eight CPU-intensive tasks:
	thermal thermal_zone3: critical temperature reached(121 C),shutting down

This seems to be specific to Odroid XU3-Lite board which officially
supports lower frequencies than regular XU3 or XU4. When working at
maximum CPU speed (1800 MHz big and 1300 MHz LITTLE) in warmer place for
longer time, the fan fails to cool down the board and it reaches
critical temperature.

Add CPU cooling to Exynos5422/5800 to fix this issue. When reaching 95
degrees of Celsius, the board will slow down by 3 steps (around
1400/1000 MHz). When reaching 110 degrees of Celsius go to 600 MHz.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
---
 arch/arm/boot/dts/exynos5422-cpu-thermal.dtsi | 41 +++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5422-cpu-thermal.dtsi b/arch/arm/boot/dts/exynos5422-cpu-thermal.dtsi
index 2b289d7c0d13..66073ce29aee 100644
--- a/arch/arm/boot/dts/exynos5422-cpu-thermal.dtsi
+++ b/arch/arm/boot/dts/exynos5422-cpu-thermal.dtsi
@@ -34,6 +34,16 @@
 					hysteresis = <5000>; /* millicelsius */
 					type = "active";
 				};
+				cpu_alert3: cpu-alert-3 {
+					temperature = <95000>; /* millicelsius */
+					hysteresis = <5000>; /* millicelsius */
+					type = "passive";
+				};
+				cpu_alert4: cpu-alert-4 {
+					temperature = <110000>; /* millicelsius */
+					hysteresis = <5000>; /* millicelsius */
+					type = "passive";
+				};
 				cpu_crit0: cpu-crit-0 {
 					temperature = <120000>; /* millicelsius */
 					hysteresis = <0>; /* millicelsius */
@@ -53,6 +63,37 @@
 				     trip = <&cpu_alert2>;
 				     cooling-device = <&fan0 2 3>;
 				};
+
+				/*
+				 * When reaching cpu_alert3, reduce CPU
+				 * by 3 steps. On Exynos5422/5800 that would
+				 * be: 1400 MHz and 1000 MHz.
+				 */
+				map3 {
+				     trip = <&cpu_alert3>;
+				     cooling-device = <&cpu0 3 3>;
+				};
+				map4 {
+				     trip = <&cpu_alert3>;
+				     cooling-device = <&cpu4 3 3>;
+				};
+
+				/*
+				 * When reaching cpu_alert4, reduce CPU
+				 * to 600 MHz (11 steps for big, 7 steps for
+				 * LITTLE).
+				 * Exynos5420 has less OPPs and reversed
+				 * numbering of CPUs (big/LITTLE) so this
+				 * would not match.
+				 */
+				map5 {
+				     trip = <&cpu_alert4>;
+				     cooling-device = <&cpu0 7 7>;
+				};
+				map6 {
+				     trip = <&cpu_alert4>;
+				     cooling-device = <&cpu4 11 11>;
+				};
 			};
 		};
 	};
-- 
2.5.0

Back to linux.kernel | Previous | NextNext in thread | Find similar | Unroll thread


Thread

[RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-02-17 08:00 +0100
  Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Anand Moon <linux.amoon@gmail.com> - 2016-02-17 21:00 +0100
    Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-02-18 02:50 +0100
      Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high  load Viresh Kumar <viresh.kumar@linaro.org> - 2016-02-18 03:40 +0100
        Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Anand Moon <linux.amoon@gmail.com> - 2016-02-18 04:00 +0100
        Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-02-18 05:50 +0100
          Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Marek Szyprowski <m.szyprowski@samsung.com> - 2016-02-18 11:00 +0100
            Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-02-19 01:00 +0100
      Re: [RFC 3/3] ARM: dts: Don't overheat the Odroid XU3-Lite on high load Anand Moon <linux.amoon@gmail.com> - 2016-02-18 04:20 +0100

csiph-web