The following dt entries are added:
cpus [0-3] (Cortex A53):
- capacity-dmips-mhz = <592>;
cpus [4-7] (Cortex A73):
- capacity-dmips-mhz = <1024>;
Those values were obtained by running dhrystone 2.1 on a
HiKey960 with the following procedure:
- Offline all CPUs but CPU0 (A53)
- Set CPU0 frequency to maximum
- Run Dhrystone 2.1 for 20 seconds
- Offline all CPUs but CPU4 (A73)
- set CPU4 frequency to maximum
- Run Dhrystone 2.1 for 20 seconds
The results are as follows:
A53: 129633887 loops
A73: 287034147 loops
By scaling those values so that the A73s use 1024, we end up with 462
for the A53s. However, they have different maximum frequencies:
1.844GHz for A53s and 2.362GHz for A73s. Thus, we can scale the A53
value to truly represent dmips per MHz, and we end up with 592.
The impact of this change can be verified on HiKey960:
$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq
1844000
1844000
1844000
1844000
2362000
2362000
2362000
2362000
$ cat /sys/devices/system/cpu/cpu*/cpu_capacity
462
462
462
462
1024
1024
1024
1024
Signed-off-by: Valentin Schneider <[email protected]>
---
arch/arm64/boot/dts/hisilicon/hi3660.dtsi | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
index ab0b95b..04a8d28 100644
--- a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
+++ b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
@@ -61,6 +61,7 @@
enable-method = "psci";
next-level-cache = <&A53_L2>;
cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
+ capacity-dmips-mhz = <592>;
};
cpu1: cpu@1 {
@@ -70,6 +71,7 @@
enable-method = "psci";
next-level-cache = <&A53_L2>;
cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
+ capacity-dmips-mhz = <592>;
};
cpu2: cpu@2 {
@@ -79,6 +81,7 @@
enable-method = "psci";
next-level-cache = <&A53_L2>;
cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
+ capacity-dmips-mhz = <592>;
};
cpu3: cpu@3 {
@@ -88,6 +91,7 @@
enable-method = "psci";
next-level-cache = <&A53_L2>;
cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
+ capacity-dmips-mhz = <592>;
};
cpu4: cpu@100 {
@@ -101,6 +105,7 @@
&CPU_SLEEP
&CLUSTER_SLEEP_1
>;
+ capacity-dmips-mhz = <1024>;
};
cpu5: cpu@101 {
@@ -114,6 +119,7 @@
&CPU_SLEEP
&CLUSTER_SLEEP_1
>;
+ capacity-dmips-mhz = <1024>;
};
cpu6: cpu@102 {
@@ -127,6 +133,7 @@
&CPU_SLEEP
&CLUSTER_SLEEP_1
>;
+ capacity-dmips-mhz = <1024>;
};
cpu7: cpu@103 {
@@ -140,6 +147,7 @@
&CPU_SLEEP
&CLUSTER_SLEEP_1
>;
+ capacity-dmips-mhz = <1024>;
};
idle-states {
--
2.7.4
Hi Valentin,
On Wed, Dec 13, 2017 at 02:21:06PM +0000, Valentin Schneider wrote:
> The following dt entries are added:
> cpus [0-3] (Cortex A53):
> - capacity-dmips-mhz = <592>;
>
> cpus [4-7] (Cortex A73):
> - capacity-dmips-mhz = <1024>;
>
> Those values were obtained by running dhrystone 2.1 on a
> HiKey960 with the following procedure:
> - Offline all CPUs but CPU0 (A53)
> - Set CPU0 frequency to maximum
> - Run Dhrystone 2.1 for 20 seconds
>
> - Offline all CPUs but CPU4 (A73)
> - set CPU4 frequency to maximum
> - Run Dhrystone 2.1 for 20 seconds
>
> The results are as follows:
> A53: 129633887 loops
> A73: 287034147 loops
Seems to me the capacity-dmips-mhz should be:
CA53: 129633887 / 20 / 1844 = 3515
CA73: 287034147 / 20 / 2362 = 6076
After normalized to range [0..1024], we could get:
CA53: 592
CA73: 1024
Reviewed-by: Leo Yan <[email protected]>
> By scaling those values so that the A73s use 1024, we end up with 462
> for the A53s. However, they have different maximum frequencies:
> 1.844GHz for A53s and 2.362GHz for A73s. Thus, we can scale the A53
> value to truly represent dmips per MHz, and we end up with 592.
>
> The impact of this change can be verified on HiKey960:
>
> $ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq
> 1844000
> 1844000
> 1844000
> 1844000
> 2362000
> 2362000
> 2362000
> 2362000
>
> $ cat /sys/devices/system/cpu/cpu*/cpu_capacity
> 462
> 462
> 462
> 462
> 1024
> 1024
> 1024
> 1024
>
> Signed-off-by: Valentin Schneider <[email protected]>
> ---
> arch/arm64/boot/dts/hisilicon/hi3660.dtsi | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
> index ab0b95b..04a8d28 100644
> --- a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
> +++ b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
> @@ -61,6 +61,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu1: cpu@1 {
> @@ -70,6 +71,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu2: cpu@2 {
> @@ -79,6 +81,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu3: cpu@3 {
> @@ -88,6 +91,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu4: cpu@100 {
> @@ -101,6 +105,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> cpu5: cpu@101 {
> @@ -114,6 +119,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> cpu6: cpu@102 {
> @@ -127,6 +133,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> cpu7: cpu@103 {
> @@ -140,6 +147,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> idle-states {
> --
> 2.7.4
>
Hi Leo,
On 12/13/2017 02:53 PM, Leo Yan wrote:
> Hi Valentin,
>
> On Wed, Dec 13, 2017 at 02:21:06PM +0000, Valentin Schneider wrote:
>> The following dt entries are added:
>> cpus [0-3] (Cortex A53):
>> - capacity-dmips-mhz = <592>;
>>
>> cpus [4-7] (Cortex A73):
>> - capacity-dmips-mhz = <1024>;
>>
>> Those values were obtained by running dhrystone 2.1 on a
>> HiKey960 with the following procedure:
>> - Offline all CPUs but CPU0 (A53)
>> - Set CPU0 frequency to maximum
>> - Run Dhrystone 2.1 for 20 seconds
>>
>> - Offline all CPUs but CPU4 (A73)
>> - set CPU4 frequency to maximum
>> - Run Dhrystone 2.1 for 20 seconds
>>
>> The results are as follows:
>> A53: 129633887 loops
>> A73: 287034147 loops
> Seems to me the capacity-dmips-mhz should be:
>
> CA53: 129633887 / 20 / 1844 = 3515
> CA73: 287034147 / 20 / 2362 = 6076
>
> After normalized to range [0..1024], we could get:
>
> CA53: 592
> CA73: 1024
Yes, that's the "direct approach". I wanted to underline the fact that
there are two different max frequencies so what I followed would be:
1) Computing the performance ratio:
(129633887 / 287034147) * 1024 = 462.47
2) Scaling that to the same frequency scale:
462.47 * (2362/1844) = 592.38
Which gives the same end result (it's the same equation but split in two
steps). Also it makes it easy to check that the cpu_capacity sysfs entry
for the A53s gets correctly set (to 462).
>
> Reviewed-by: Leo Yan <[email protected]>
>
>> By scaling those values so that the A73s use 1024, we end up with 462
>> for the A53s. However, they have different maximum frequencies:
>> 1.844GHz for A53s and 2.362GHz for A73s. Thus, we can scale the A53
>> value to truly represent dmips per MHz, and we end up with 592.
>>
>> The impact of this change can be verified on HiKey960:
>>
>> $ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq
>> 1844000
>> 1844000
>> 1844000
>> 1844000
>> 2362000
>> 2362000
>> 2362000
>> 2362000
>>
>> $ cat /sys/devices/system/cpu/cpu*/cpu_capacity
>> 462
>> 462
>> 462
>> 462
>> 1024
>> 1024
>> 1024
>> 1024
>>
>> Signed-off-by: Valentin Schneider <[email protected]>
>> ---
>> arch/arm64/boot/dts/hisilicon/hi3660.dtsi | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
>> index ab0b95b..04a8d28 100644
>> --- a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
>> +++ b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
>> @@ -61,6 +61,7 @@
>> enable-method = "psci";
>> next-level-cache = <&A53_L2>;
>> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
>> + capacity-dmips-mhz = <592>;
>> };
>>
>> cpu1: cpu@1 {
>> @@ -70,6 +71,7 @@
>> enable-method = "psci";
>> next-level-cache = <&A53_L2>;
>> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
>> + capacity-dmips-mhz = <592>;
>> };
>>
>> cpu2: cpu@2 {
>> @@ -79,6 +81,7 @@
>> enable-method = "psci";
>> next-level-cache = <&A53_L2>;
>> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
>> + capacity-dmips-mhz = <592>;
>> };
>>
>> cpu3: cpu@3 {
>> @@ -88,6 +91,7 @@
>> enable-method = "psci";
>> next-level-cache = <&A53_L2>;
>> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
>> + capacity-dmips-mhz = <592>;
>> };
>>
>> cpu4: cpu@100 {
>> @@ -101,6 +105,7 @@
>> &CPU_SLEEP
>> &CLUSTER_SLEEP_1
>> >;
>> + capacity-dmips-mhz = <1024>;
>> };
>>
>> cpu5: cpu@101 {
>> @@ -114,6 +119,7 @@
>> &CPU_SLEEP
>> &CLUSTER_SLEEP_1
>> >;
>> + capacity-dmips-mhz = <1024>;
>> };
>>
>> cpu6: cpu@102 {
>> @@ -127,6 +133,7 @@
>> &CPU_SLEEP
>> &CLUSTER_SLEEP_1
>> >;
>> + capacity-dmips-mhz = <1024>;
>> };
>>
>> cpu7: cpu@103 {
>> @@ -140,6 +147,7 @@
>> &CPU_SLEEP
>> &CLUSTER_SLEEP_1
>> >;
>> + capacity-dmips-mhz = <1024>;
>> };
>>
>> idle-states {
>> --
>> 2.7.4
>>
On Wed, Dec 13, 2017 at 03:16:13PM +0000, Valentin Schneider wrote:
> Hi Leo,
>
>
> On 12/13/2017 02:53 PM, Leo Yan wrote:
> >Hi Valentin,
> >
> >On Wed, Dec 13, 2017 at 02:21:06PM +0000, Valentin Schneider wrote:
> >>The following dt entries are added:
> >> cpus [0-3] (Cortex A53):
> >> - capacity-dmips-mhz = <592>;
> >>
> >> cpus [4-7] (Cortex A73):
> >> - capacity-dmips-mhz = <1024>;
> >>
> >>Those values were obtained by running dhrystone 2.1 on a
> >>HiKey960 with the following procedure:
> >>- Offline all CPUs but CPU0 (A53)
> >>- Set CPU0 frequency to maximum
> >>- Run Dhrystone 2.1 for 20 seconds
> >>
> >>- Offline all CPUs but CPU4 (A73)
> >>- set CPU4 frequency to maximum
> >>- Run Dhrystone 2.1 for 20 seconds
> >>
> >>The results are as follows:
> >>A53: 129633887 loops
> >>A73: 287034147 loops
> >Seems to me the capacity-dmips-mhz should be:
> >
> >CA53: 129633887 / 20 / 1844 = 3515
> >CA73: 287034147 / 20 / 2362 = 6076
> >
> >After normalized to range [0..1024], we could get:
> >
> >CA53: 592
> >CA73: 1024
>
> Yes, that's the "direct approach". I wanted to underline the fact that there
> are two different max frequencies so what I followed would be:
>
> 1) Computing the performance ratio:
> (129633887 / 287034147) * 1024 = 462.47
>
> 2) Scaling that to the same frequency scale:
> 462.47 * (2362/1844) = 592.38
>
> Which gives the same end result (it's the same equation but split in two
> steps). Also it makes it easy to check that the cpu_capacity sysfs entry for
> the A53s gets correctly set (to 462).
Yeah, thanks for clear explanation.
[...]
Thanks,
Leo Yan
Hi Valentin,
On 2017/12/13 14:21, Valentin Schneider wrote:
> The following dt entries are added:
> cpus [0-3] (Cortex A53):
> - capacity-dmips-mhz = <592>;
>
> cpus [4-7] (Cortex A73):
> - capacity-dmips-mhz = <1024>;
>
> Those values were obtained by running dhrystone 2.1 on a
> HiKey960 with the following procedure:
> - Offline all CPUs but CPU0 (A53)
> - Set CPU0 frequency to maximum
> - Run Dhrystone 2.1 for 20 seconds
>
> - Offline all CPUs but CPU4 (A73)
> - set CPU4 frequency to maximum
> - Run Dhrystone 2.1 for 20 seconds
>
> The results are as follows:
> A53: 129633887 loops
> A73: 287034147 loops
>
> By scaling those values so that the A73s use 1024, we end up with 462
> for the A53s. However, they have different maximum frequencies:
> 1.844GHz for A53s and 2.362GHz for A73s. Thus, we can scale the A53
> value to truly represent dmips per MHz, and we end up with 592.
>
> The impact of this change can be verified on HiKey960:
>
> $ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq
> 1844000
> 1844000
> 1844000
> 1844000
> 2362000
> 2362000
> 2362000
> 2362000
>
> $ cat /sys/devices/system/cpu/cpu*/cpu_capacity
> 462
> 462
> 462
> 462
> 1024
> 1024
> 1024
> 1024
>
> Signed-off-by: Valentin Schneider <[email protected]>
> ---
Applied into hisilicon dt tree.
Thanks!
Best Regards,
Wei
> arch/arm64/boot/dts/hisilicon/hi3660.dtsi | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
> index ab0b95b..04a8d28 100644
> --- a/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
> +++ b/arch/arm64/boot/dts/hisilicon/hi3660.dtsi
> @@ -61,6 +61,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu1: cpu@1 {
> @@ -70,6 +71,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu2: cpu@2 {
> @@ -79,6 +81,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu3: cpu@3 {
> @@ -88,6 +91,7 @@
> enable-method = "psci";
> next-level-cache = <&A53_L2>;
> cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP_0>;
> + capacity-dmips-mhz = <592>;
> };
>
> cpu4: cpu@100 {
> @@ -101,6 +105,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> cpu5: cpu@101 {
> @@ -114,6 +119,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> cpu6: cpu@102 {
> @@ -127,6 +133,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> cpu7: cpu@103 {
> @@ -140,6 +147,7 @@
> &CPU_SLEEP
> &CLUSTER_SLEEP_1
> >;
> + capacity-dmips-mhz = <1024>;
> };
>
> idle-states {
> --
> 2.7.4
>
>
> .
>