arm64: dts: Add mali power_model to juno dts

Signed-off-by: Jon Medhurst <tixy@linaro.org>
[Assign GPU to SoC thermal zone]
Signed-off-by: Arvind Chauhan <arvind.chauhan@arm.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/arch/arm64/boot/dts/arm/juno-base.dtsi b/arch/arm64/boot/dts/arm/juno-base.dtsi
index d2bf12d44ac6..b3729dfa7743 100644
--- a/arch/arm64/boot/dts/arm/juno-base.dtsi
+++ b/arch/arm64/boot/dts/arm/juno-base.dtsi
@@ -677,6 +677,42 @@
 		interrupt-names = "JOB", "MMU", "GPU";
 		clocks = <&scmi_dvfs 2>;
 		power-domains = <&scmi_devpd 9>;
+		power_model {
+			compatible = "arm,mali-simple-power-model";
+			voltage = <800>;
+			frequency = <500>;
+			static-power = <500>;
+			dynamic-power = <1500>;
+			ts = <20000 2000 (-20) 2>;
+			/*
+			 * We can't have a proper GPU thermal zone because Juno
+			 * r1 & r2 have two sensors which Linux doesn't support
+			 * yet, and for r0 there isn't a separate sensor.
+			 *
+			 * We also can't create a GPU thermal zone that reuses
+			 * the SoC sensor because of another limitation in Linux
+			 * code that prevents sensors being used for more that
+			 * one zone.
+			 *
+			 * Warning for the future: Mali contains very dubious
+			 * code for setting up OPPs which does a global search
+			 * of device-tree for a node called "gpu" and expects
+			 * this to be the Mali device. So if we do the natural
+			 * thing for a GPU thermal zone and call that node "gpu"
+			 * then Mali OPP code will go horribly wrong. We should
+			 * therefore call it something different or fix Mali
+			 * code to not be so lame.
+			 *
+			 * With all the above in mind, we will assign here the
+			 * GPU to the to the SoC thermal zone and hope that
+			 * there's no recursive deadlocks that can occur. E.g.
+			 * SoC cooling triggers Mali devfreq cooling and because
+			 * that is in the SoC thermal zone it tries to
+			 * recursively trigger cooling on the SoC zone.
+			 * (This doesn't appear to happen).
+			 */
+			thermal-zone = "soc";
+		};
 	};
 
 	smb@08000000 {