linux/arch/arm/boot/dts/exynos5422-cpus.dtsi
Lukasz Luba e4dcb4ab3b ARM: dts: exynos: Add dynamic-power-coefficient to Exynos5422 CPUs
To use Energy Aware Scheduler (EAS) the Energy Model (EM) should be
registered for CPUs. Add dynamic-power-coefficient into CPU nodes which
let CPUFreq subsystem register the EM structures. This will increase
energy efficiency of big.LITTLE platforms.

The 'dynamic-power-coefficient' values have been obtained experimenting
with different workloads. The power measurements taken from big CPU
Cluster and LITTLE CPU Cluster has been compared with official documents
and synthetic workloads estimations. The effective power ratio between
Cortex-A7 and Cortex-A15 CPUs (~3x) is also aligned with documentation.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2020-02-20 18:56:05 +01:00

139 lines
3.8 KiB
Plaintext

// SPDX-License-Identifier: GPL-2.0
/*
* Samsung Exynos5422 SoC cpu device tree source
*
* Copyright (c) 2015 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* This file provides desired ordering for Exynos5422: CPU[0123] being the A7.
*
* The Exynos5420, 5422 and 5800 actually share the same CPU configuration
* but particular boards choose different booting order.
*
* Exynos5420 and Exynos5800 always boot from Cortex-A15. On Exynos5422
* booting cluster (big or LITTLE) is chosen by IROM code by reading
* the gpg2-1 GPIO. By default all Exynos5422 based boards choose booting
* from the LITTLE: Cortex-A7.
*/
/ {
cpus {
#address-cells = <1>;
#size-cells = <0>;
cpu0: cpu@100 {
device_type = "cpu";
compatible = "arm,cortex-a7";
reg = <0x100>;
clocks = <&clock CLK_KFC_CLK>;
clock-frequency = <1000000000>;
cci-control-port = <&cci_control0>;
operating-points-v2 = <&cluster_a7_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <539>;
dynamic-power-coefficient = <90>;
};
cpu1: cpu@101 {
device_type = "cpu";
compatible = "arm,cortex-a7";
reg = <0x101>;
clocks = <&clock CLK_KFC_CLK>;
clock-frequency = <1000000000>;
cci-control-port = <&cci_control0>;
operating-points-v2 = <&cluster_a7_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <539>;
dynamic-power-coefficient = <90>;
};
cpu2: cpu@102 {
device_type = "cpu";
compatible = "arm,cortex-a7";
reg = <0x102>;
clocks = <&clock CLK_KFC_CLK>;
clock-frequency = <1000000000>;
cci-control-port = <&cci_control0>;
operating-points-v2 = <&cluster_a7_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <539>;
dynamic-power-coefficient = <90>;
};
cpu3: cpu@103 {
device_type = "cpu";
compatible = "arm,cortex-a7";
reg = <0x103>;
clocks = <&clock CLK_KFC_CLK>;
clock-frequency = <1000000000>;
cci-control-port = <&cci_control0>;
operating-points-v2 = <&cluster_a7_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <539>;
dynamic-power-coefficient = <90>;
};
cpu4: cpu@0 {
device_type = "cpu";
compatible = "arm,cortex-a15";
reg = <0x0>;
clocks = <&clock CLK_ARM_CLK>;
clock-frequency = <1800000000>;
cci-control-port = <&cci_control1>;
operating-points-v2 = <&cluster_a15_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <1024>;
dynamic-power-coefficient = <310>;
};
cpu5: cpu@1 {
device_type = "cpu";
compatible = "arm,cortex-a15";
reg = <0x1>;
clocks = <&clock CLK_ARM_CLK>;
clock-frequency = <1800000000>;
cci-control-port = <&cci_control1>;
operating-points-v2 = <&cluster_a15_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <1024>;
dynamic-power-coefficient = <310>;
};
cpu6: cpu@2 {
device_type = "cpu";
compatible = "arm,cortex-a15";
reg = <0x2>;
clocks = <&clock CLK_ARM_CLK>;
clock-frequency = <1800000000>;
cci-control-port = <&cci_control1>;
operating-points-v2 = <&cluster_a15_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <1024>;
dynamic-power-coefficient = <310>;
};
cpu7: cpu@3 {
device_type = "cpu";
compatible = "arm,cortex-a15";
reg = <0x3>;
clocks = <&clock CLK_ARM_CLK>;
clock-frequency = <1800000000>;
cci-control-port = <&cci_control1>;
operating-points-v2 = <&cluster_a15_opp_table>;
#cooling-cells = <2>; /* min followed by max */
capacity-dmips-mhz = <1024>;
dynamic-power-coefficient = <310>;
};
};
};
&arm_a7_pmu {
interrupt-affinity = <&cpu0>, <&cpu1>, <&cpu2>, <&cpu3>;
status = "okay";
};
&arm_a15_pmu {
interrupt-affinity = <&cpu4>, <&cpu5>, <&cpu6>, <&cpu7>;
status = "okay";
};