[PATCH 4.19.y-cip 20/22] arm64: dts: renesas: r8a774a1: Add CPU capacity-dmips-mhz


Biju Das <biju.das@...>
 

commit 5f5249497bd7ed65d90cac36c3c3dabcda2903dd upstream.

Set the capacity-dmips-mhz for RZ/G2M(r8a774a1) SoC, that is based on
dhrystone.

Based on work done by Gaku Inami <gaku.inami.xw@...> for
r8a7796 SoC.

The average dhrystone result for 5 iterations is as below:

r8a774a1 SoC (CA57x2 + CA53x4)
CPU max-freq dhrystone
---------------------------------
CA57 1500 MHz 11428571 lps/s
CA53 1200 MHz 5000000 lps/s

From this, CPU capacity-dmips-mhz for CA57 and CA53 are calculated
as follows:

r8a774a1 SoC
CA57 : 1024 / (11428571 / 1500) * (11428571 / 1500) = 1024
CA53 : 1024 / (11428571 / 1500) * ( 5000000 / 1200) = 560

Since each CPUs have different max frequencies, the final CPU
capacities of A53 scaled by the above difference is as below

$ cat /sys/devices/system/cpu/cpu*/cpu_capacity
1024
1024
448
448
448
448

Signed-off-by: Biju Das <biju.das@...>
Signed-off-by: Simon Horman <horms+renesas@...>
---
arch/arm64/boot/dts/renesas/r8a774a1.dtsi | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/arm64/boot/dts/renesas/r8a774a1.dtsi b/arch/arm64/boot/dts/renesas/r8a774a1.dtsi
index 50f3f17..0e755b8 100644
--- a/arch/arm64/boot/dts/renesas/r8a774a1.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a774a1.dtsi
@@ -137,6 +137,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A774A1_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
};

a57_1: cpu@1 {
@@ -148,6 +149,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A774A1_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
};

a53_0: cpu@100 {
@@ -159,6 +161,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A774A1_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <560>;
};

a53_1: cpu@101 {
@@ -170,6 +173,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A774A1_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <560>;
};

a53_2: cpu@102 {
@@ -181,6 +185,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A774A1_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <560>;
};

a53_3: cpu@103 {
@@ -192,6 +197,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A774A1_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <560>;
};

L2_CA57: cache-controller-0 {
--
2.7.4

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