[PATCH 3/4] arm: dts: exynos: add exynos5422 cpu capacity-dmips-mhz information

From: Dietmar Eggemann
Date: Wed Aug 30 2017 - 10:42:12 EST


The following 'capacity-dmips-mhz' dt property values are used:

Cortex-A15: 1024, Cortex-A7: 539

They have been derived form the cpu_efficiency values:

Cortex-A15: 3891, Cortex-A7: 2048

by scaling them so that the Cortex-A15s (big cores) use 1024.

The cpu_efficiency values were originally derived from the "Big.LITTLE
Processing with ARM Cortexâ-A15 & Cortex-A7" white paper
(http://www.cl.cam.ac.uk/~rdm34/big.LITTLE.pdf). Table 1 lists 1.9x
(3891/2048) as the Cortex-A15 vs Cortex-A7 performance ratio for the
Dhrystone benchmark.

The following platforms are affected once cpu-invariant accounting
support is re-connected to the task scheduler:

odroidxu3, odroidxu3-lite, odroidxu4

Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Kukjin Kim <kgene@xxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
---
arch/arm/boot/dts/exynos5422-cpus.dtsi | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5422-cpus.dtsi b/arch/arm/boot/dts/exynos5422-cpus.dtsi
index bf3c6f1ec4ee..ec01d8020c2d 100644
--- a/arch/arm/boot/dts/exynos5422-cpus.dtsi
+++ b/arch/arm/boot/dts/exynos5422-cpus.dtsi
@@ -35,6 +35,7 @@
cooling-min-level = <0>;
cooling-max-level = <11>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <539>;
};

cpu1: cpu@101 {
@@ -47,6 +48,7 @@
cooling-min-level = <0>;
cooling-max-level = <11>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <539>;
};

cpu2: cpu@102 {
@@ -59,6 +61,7 @@
cooling-min-level = <0>;
cooling-max-level = <11>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <539>;
};

cpu3: cpu@103 {
@@ -71,6 +74,7 @@
cooling-min-level = <0>;
cooling-max-level = <11>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <539>;
};

cpu4: cpu@0 {
@@ -84,6 +88,7 @@
cooling-min-level = <0>;
cooling-max-level = <15>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <1024>;
};

cpu5: cpu@1 {
@@ -96,6 +101,7 @@
cooling-min-level = <0>;
cooling-max-level = <15>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <1024>;
};

cpu6: cpu@2 {
@@ -108,6 +114,7 @@
cooling-min-level = <0>;
cooling-max-level = <15>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <1024>;
};

cpu7: cpu@3 {
@@ -120,6 +127,7 @@
cooling-min-level = <0>;
cooling-max-level = <15>;
#cooling-cells = <2>; /* min followed by max */
+ capacity-dmips-mhz = <1024>;
};
};
};
--
2.11.0