CPU
Contents
1 S5P4418/S5P6818
1.1 锁定CPU的最高频率
1.1.1 Method 1
The following command is used to temporarily limit the maximum CPU frequency to 1GHz: echo 1000000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
1.1.2 Method 2
Modify the kernel source code:
arch/arm/plat-s5p4418/nanopi2/device.c
Delete the unwanted frequencies in the following array:
static unsigned long dfs_freq_table[][2] = {
{ 1400000, 1200000, },
{ 1200000, 1120000, },
{ 1000000, 1040000, },
{ 800000, 1000000, },
{ 700000, 940000, },
{ 600000, 940000, },
{ 500000, 940000, },
{ 400000, 940000, },
};1.2 CPU thermal
读取以下文件获得当前的CPU温度：
S5P4418/S5P6818:
/sys/class/hwmon/hwmon0/device/temp_label
Allwinner H3/H5/A64:
/sys/class/thermal/thermal_zone0/temp
RK3399，获取CPU温度和运行频率:
while true; do t1=`cat /sys/class/thermal/thermal_zone0/temp` t2=`cat /sys/class/thermal/thermal_zone1/temp` f1=`cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq` f2=`cat /sys/devices/system/cpu/cpu4/cpufreq/cpuinfo_cur_freq` echo "$t1 $t2 $f1 $f2" sleep 1 #cat /sys/class/thermal/thermal_zone[01]/temp #cat /sys/devices/system/cpu/cpu[04]/cpufreq/cpuinfo_cur_freq done
2 H3
2.1 CPU DVFS
2.1.1 Linux-4.14
对于H3系列的开发板，使用的都是同样的DVFS设置，相关代码位于arch/arm/boot/dts/sun8i-h3-nanopi.dtsi:
&cpu0 {
operating-points = <
1008000 1300000
816000 1100000
624000 1100000
480000 1100000
312000 1100000
240000 1100000
120000 1100000
>;
#cooling-cells = <2>;
cooling-min-level = <0>;
cooling-max-level = <6>;
cpu0-supply = <&vdd_cpux>;
};
&cpu_thermal {
trips {
cpu_warm: cpu_warm {
temperature = <65000>;
hysteresis = <2000>;
type = "passive";
};
cpu_hot: cpu_hot {
temperature = <75000>;
hysteresis = <2000>;
type = "passive";
};
cpu_very_hot: cpu_very_hot {
temperature = <90000>;
hysteresis = <2000>;
type = "passive";
};
cpu_crit: cpu_crit {
temperature = <105000>;
hysteresis = <2000>;
type = "critical";
};
};
cooling-maps {
cpu_warm_limit_cpu {
trip = <&cpu_warm>;
cooling-device = <&cpu0 THERMAL_NO_LIMIT 1>;
};
cpu_hot_limit_cpu {
trip = <&cpu_hot>;
cooling-device = <&cpu0 2 3>;
};
cpu_very_hot_limit_cpu {
trip = <&cpu_very_hot>;
cooling-device = <&cpu0 5 THERMAL_NO_LIMIT>;
};
};
};2.2 CPU ID
2.2.1 Linux-4.14
As for Allwinner H2+/H3/H5/ SoCs each of these CPUs has an internal 16-btye CHIP ID which can be read by running the following commands in the Linux-4.14 kernel:
$ apt-get install bsdmainutils $ hexdump /sys/bus/nvmem/devices/sunxi-sid0/nvmem 0000000 8082 0447 0064 04c3 3650 ce0a 1e28 2202 0000010 0002 0000 0000 0000 0000 0000 0000 0000 0000020 0000 0000 0000 0000 0000 0000 0000 0000 0000030 0000 0008 0508 0000 0000 0000 0000 0000 0000040 0000 0000 0000 0000 0000 0000 0000 0000
"8082 0447 0064 04c3 3650 ce0a 1e28 2202" is the 16-byte CHIP ID.
2.3 CPU thermal
$ cat /sys/class/thermal/thermal_zone0/temp 30489
表示当前CPU温度为30.489摄氏度。
3 H5
3.1 CPU DVFS
3.1.1 Linux-4.14
对于H5系列的开发板，不同型号的DVFS设置是不一样的。 以NanoPi NEO2为例，相关代码位于arch/arm64/boot/dts/allwinner/sun50i-h5-nanopi-neo2.dts:
&cpu0 {
operating-points = <
1008000 1100000
816000 1100000
624000 1100000
480000 1100000
312000 1100000
240000 1100000
120000 1100000
>;
#cooling-cells = <2>;
cooling-min-level = <0>;
cooling-max-level = <6>;
cpu0-supply = <&vdd_cpux>;
};
&cpu_thermal {
trips {
cpu_warm: cpu_warm {
temperature = <65000>;
hysteresis = <2000>;
type = "passive";
};
cpu_hot: cpu_hot {
temperature = <75000>;
hysteresis = <2000>;
type = "passive";
};
cpu_very_hot: cpu_very_hot {
temperature = <90000>;
hysteresis = <2000>;
type = "passive";
};
cpu_crit: cpu_crit {
temperature = <105000>;
hysteresis = <2000>;
type = "critical";
};
};
cooling-maps {
cpu_warm_limit_cpu {
trip = <&cpu_warm>;
cooling-device = <&cpu0 THERMAL_NO_LIMIT 1>;
};
cpu_hot_limit_cpu {
trip = <&cpu_hot>;
cooling-device = <&cpu0 2 3>;
};
cpu_very_hot_limit_cpu {
trip = <&cpu_very_hot>;
cooling-device = <&cpu0 5 THERMAL_NO_LIMIT>;
};
};
};3.2 CPU ID
3.2.1 Linux-4.14
As for Allwinner H2+/H3/H5/ SoCs each of these CPUs has an internal 16-btye CHIP ID which can be read by running the following commands in the Linux-4.14 kernel:
$ apt-get install bsdmainutils $ hexdump /sys/bus/nvmem/devices/sunxi-sid0/nvmem 0000000 8082 0447 0064 04c3 3650 ce0a 1e28 2202 0000010 0002 0000 0000 0000 0000 0000 0000 0000 0000020 0000 0000 0000 0000 0000 0000 0000 0000 0000030 0000 0008 0508 0000 0000 0000 0000 0000 0000040 0000 0000 0000 0000 0000 0000 0000 0000
"8082 0447 0064 04c3 3650 ce0a 1e28 2202" is the 16-byte CHIP ID.
3.3 CPU thermal
$ cat /sys/class/thermal/thermal_zone0/temp 30489
表示当前CPU温度为30.489摄氏度。
