Set the capacity-dmips-mhz for R-Car Gen3 SoCs, that is based on
dhrystone. The average in 10 times of dhrystone result as follows:
r8a7795 SoC (A57x4 + A53x4)
CPU max-freq dhrystone
---------------------------------
A57 1500 MHz 11470943 lps/s
A53 1200 MHz 4798583 lps/s
r8a7796 SoC (A57x2 + A53x4)
CPU max-freq dhrystone
---------------------------------
A57 1500 MHz 11463526 lps/s
A53 1200 MHz 4793276 lps/s
Based on above, capacity-dmips-mhz values are calculated as follows:
r8a7795 SoC
A57 : 1024 / (11470943 / 1500) * (11470943 / 1500) = 1024
A53 : 1024 / (11470943 / 1500) * ( 4798583 / 1200) = 535
r8a7796 SoC
A57 : 1024 / (11463526 / 1500) * (11463526 / 1500) = 1024
A53 : 1024 / (11463526 / 1500) * ( 4793276 / 1200) = 535
However, since each CPUs have different max frequencies, the final
CPU capacities of A53 are scaled by this difference, the values are
as follows.
[r8a7795 SoC]
$ cat /sys/devices/system/cpu/cpu*/cpu_capacity
1024 <---- CPU capacity of A57
1024
1024
1024
428 <---- CPU capacity of A53
428
428
428
[r8a7796 SoC]
$ cat /sys/devices/system/cpu/cpu*/cpu_capacity
1024 <---- CPU capacity of A57
1024
428 <---- CPU capacity of A53
428
428
428
Signed-off-by: Gaku Inami <gaku.inami.xh@xxxxxxxxxxx>
---
v1 -> v2:
- Consolidate two patches for r8a7795 and r8a7796 into one patch
- Add the formula for capacity-dmips-mhz into description
---
arch/arm64/boot/dts/renesas/r8a7795.dtsi | 8 ++++++++
arch/arm64/boot/dts/renesas/r8a7796.dtsi | 6 ++++++
2 files changed, 14 insertions(+)
diff --git a/arch/arm64/boot/dts/renesas/r8a7795.dtsi b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
index 63d5b61..94a4ab6 100644
--- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
@@ -157,6 +157,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
#cooling-cells = <2>;
};
@@ -169,6 +170,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
#cooling-cells = <2>;
};
@@ -181,6 +183,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
#cooling-cells = <2>;
};
@@ -193,6 +196,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
#cooling-cells = <2>;
};
@@ -205,6 +209,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
a53_1: cpu@101 {
@@ -216,6 +221,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
a53_2: cpu@102 {
@@ -227,6 +233,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
a53_3: cpu@103 {
@@ -238,6 +245,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
L2_CA57: cache-controller-0 {
diff --git a/arch/arm64/boot/dts/renesas/r8a7796.dtsi b/arch/arm64/boot/dts/renesas/r8a7796.dtsi
index b12bf73..369d0bc 100644
--- a/arch/arm64/boot/dts/renesas/r8a7796.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a7796.dtsi
@@ -162,6 +162,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7796_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
#cooling-cells = <2>;
};
@@ -174,6 +175,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7796_CLK_Z>;
operating-points-v2 = <&cluster0_opp>;
+ capacity-dmips-mhz = <1024>;
#cooling-cells = <2>;
};
@@ -186,6 +188,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7796_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
a53_1: cpu@101 {
@@ -197,6 +200,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7796_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
a53_2: cpu@102 {
@@ -208,6 +212,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7796_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
a53_3: cpu@103 {
@@ -219,6 +224,7 @@
enable-method = "psci";
clocks = <&cpg CPG_CORE R8A7796_CLK_Z2>;
operating-points-v2 = <&cluster1_opp>;
+ capacity-dmips-mhz = <535>;
};
L2_CA57: cache-controller-0 {
--
2.7.4
