From: Frank Hartung <supervisedthinking@gmail.com>
Date: Sat, 14 Sep 2019 02:49:40 +0000 (+0400)
Subject: arm64: dts: meson: Add capacity-dmips-mhz attributes to G12B
X-Git-Tag: v5.5-rc1~39^2~3^2~33
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=6eeaf4d2452ec8b1ece58776812140734fc2e088;p=linux.git

arm64: dts: meson: Add capacity-dmips-mhz attributes to G12B

Meson G12B SoCs (S922X and A311D) are a big-little design where not all CPUs
are equal; the A53s cores are weaker than the A72s.

Include capacity-dmips-mhz properties to tell the OS there is a difference
in processing capacity. The dmips values are based on similar submissions for
other A53/A72 SoCs: HiSilicon 3660 [1] and Rockchip RK3399 [2].

This change is particularly beneficial for use-cases like retro gaming where
emulators often run on a single core. The OS now chooses an A72 core instead
of an A53 core.

[1] https://lore.kernel.org/patchwork/patch/862742/
[2] https://patchwork.kernel.org/patch/10836577/

Signed-off-by: Frank Hartung <supervisedthinking@gmail.com>
Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
---

diff --git a/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi
index a9e1db0f1158..b3f9e3a02963 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi
@@ -48,6 +48,7 @@ cpu0: cpu@0 {
 			compatible = "arm,cortex-a53";
 			reg = <0x0 0x0>;
 			enable-method = "psci";
+			capacity-dmips-mhz = <592>;
 			next-level-cache = <&l2>;
 		};
 
@@ -56,6 +57,7 @@ cpu1: cpu@1 {
 			compatible = "arm,cortex-a53";
 			reg = <0x0 0x1>;
 			enable-method = "psci";
+			capacity-dmips-mhz = <592>;
 			next-level-cache = <&l2>;
 		};
 
@@ -64,6 +66,7 @@ cpu100: cpu@100 {
 			compatible = "arm,cortex-a73";
 			reg = <0x0 0x100>;
 			enable-method = "psci";
+			capacity-dmips-mhz = <1024>;
 			next-level-cache = <&l2>;
 		};
 
@@ -72,6 +75,7 @@ cpu101: cpu@101 {
 			compatible = "arm,cortex-a73";
 			reg = <0x0 0x101>;
 			enable-method = "psci";
+			capacity-dmips-mhz = <1024>;
 			next-level-cache = <&l2>;
 		};
 
@@ -80,6 +84,7 @@ cpu102: cpu@102 {
 			compatible = "arm,cortex-a73";
 			reg = <0x0 0x102>;
 			enable-method = "psci";
+			capacity-dmips-mhz = <1024>;
 			next-level-cache = <&l2>;
 		};
 
@@ -88,6 +93,7 @@ cpu103: cpu@103 {
 			compatible = "arm,cortex-a73";
 			reg = <0x0 0x103>;
 			enable-method = "psci";
+			capacity-dmips-mhz = <1024>;
 			next-level-cache = <&l2>;
 		};