@@ -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>;
+ };
};
};
};
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(+)