138 lines
5.3 KiB
Plaintext
138 lines
5.3 KiB
Plaintext
|
Thermal estimator driver.
|
||
|
|
|
||
|
|
Properties :
|
||
|
|
- compatible : Should contain "nvidia,therm-est".
|
||
|
|
- polling-period : Polling wait times for thermal estimation, in milliseconds.
|
||
|
|
- tc1 : Coefficient 1 for thermal trend calculation.
|
||
|
|
- tc2 : Coefficient 2 for thermal trend calculation.
|
||
|
|
- node for subdev : Node for subdevice information. Required.
|
||
|
|
- use_tmargin : if tmargin algorithm should be used for calculating the
|
||
|
|
effective temp. Refer Tmargin section for more info.
|
||
|
|
|
||
|
|
Properties in subdev node : Required.
|
||
|
|
- subdev_names : list of strings. It contains list of the name of the therm
|
||
|
|
zones used for estimation.
|
||
|
|
- node for coeff_set : contains a set of zone specific coefficients+offset.
|
||
|
|
This node can be numerous.
|
||
|
|
|
||
|
|
Properties in coeff_set : Required. Can be numerous.
|
||
|
|
- toffset : Temperature offset for thermal estimation, in milli-celsius.
|
||
|
|
- coeffs : An array of coefficients, the number of entries should be twenty
|
||
|
|
per sub device.
|
||
|
|
|
||
|
|
Example:
|
||
|
|
|
||
|
|
therm_est_sensor {
|
||
|
|
device_type = "therm-est-subdev";
|
||
|
|
polling-period = <1100>;
|
||
|
|
tc1 = <10>;
|
||
|
|
tc2 = <1>;
|
||
|
|
subdev {
|
||
|
|
subdev_names = "Tdiode_tegra", "Tboard_tegra";
|
||
|
|
|
||
|
|
coeff_set@0 {
|
||
|
|
toffset = <9793>;
|
||
|
|
coeffs = <
|
||
|
|
2 1 1 1 1 1 1 1 1 1 1 0 1 1 0 0 0 0 (-1) (-7)
|
||
|
|
(-11) (-7) (-5) (-3) (-3) (-2) (-1) 0 0 0 1 1 1 2 2 3 4 6 11 18
|
||
|
|
>;
|
||
|
|
};
|
||
|
|
|
||
|
|
coeff_set@1 {
|
||
|
|
toffset = <708>;
|
||
|
|
coeffs = <
|
||
|
|
-1 -1 1 1 1 1 1 1 1 1 1 0 1 1 0 0 0 (-1) (-3) (-9)
|
||
|
|
(-6) (-4) (-1) 0 0 0 0 0 0 0 1 1 1 2 2 5 7 10 17 20
|
||
|
|
>;
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
|
||
|
|
Tmargin Algorithm:
|
||
|
|
The native max temp algorithm lacks support for accomodating multiple thermal
|
||
|
|
fan curves. Tmargin algorithm solves this by calculating the effective
|
||
|
|
temperature as a difference from critical temperature of the therm fan est
|
||
|
|
group. This allows us to take a union of two fan curves and satisfy the needs
|
||
|
|
of both the therm-fan-est groups.
|
||
|
|
The algorithm use the effective temperature(crit_temp - sensor_reading) to
|
||
|
|
drive the cooling device.
|
||
|
|
|
||
|
|
Properties rules for therm-fan-est dt entry:
|
||
|
|
- use_tmargin : To use the tmargin feature.
|
||
|
|
- profiles : New profile tmargin should be defined and chosen as default.
|
||
|
|
* The trip temperatures need to be given only in ascending order for the
|
||
|
|
thermal framework to register therm-fan-est zone. Hence, the dt values
|
||
|
|
for active trip temps should be given in ascending values of tmargin
|
||
|
|
values.
|
||
|
|
* Hysterysis is used only in cooling scenario. Since tmargin is
|
||
|
|
considered as a diff wrt crit_Temp, hysterysis values should be taken
|
||
|
|
as -ve values.
|
||
|
|
|
||
|
|
Properties rules for fan dt entry:
|
||
|
|
- profiles : New profile for tmargin should be defined and chosen as default.
|
||
|
|
* The trip temps are considered in a ascending order of tmargin temps.
|
||
|
|
Hence, the pwm values should be considered in a descending order of
|
||
|
|
pwms.
|
||
|
|
* active_steps - The tmargin trip values are considered in the ascending
|
||
|
|
order(hence actual trip temps will be in descending order), so the
|
||
|
|
pwm mapping should be in the reverse order starting from 255 for
|
||
|
|
index 0.
|
||
|
|
|
||
|
|
Example :
|
||
|
|
|
||
|
|
thermal-fan-est {
|
||
|
|
compatible = "thermal-fan-est";
|
||
|
|
name = "thermal-fan-est";
|
||
|
|
status = "okay";
|
||
|
|
num_resources = <0>;
|
||
|
|
shared_data = <&thermal_fan_est_shared_data>;
|
||
|
|
trip_length = <10>;
|
||
|
|
use_tmargin;
|
||
|
|
|
||
|
|
profiles {
|
||
|
|
default = "tmargin";
|
||
|
|
quiet {
|
||
|
|
active_trip_temps = <0 50000 63000 72000 81000
|
||
|
|
140000 150000 160000 170000 180000>;
|
||
|
|
active_hysteresis = <0 18000 8000 8000 8000
|
||
|
|
0 0 0 0 0>;
|
||
|
|
};
|
||
|
|
cool {
|
||
|
|
active_trip_temps = <0 35000 53000 62000 73000
|
||
|
|
140000 150000 160000 170000 180000>;
|
||
|
|
active_hysteresis = <0 9000 8000 8000 9000
|
||
|
|
0 0 0 0 0>;
|
||
|
|
};
|
||
|
|
tmargin {
|
||
|
|
active_trip_temps = <0 10000 15000 25000 35000
|
||
|
|
45000 55000 65000 75000 105000>;
|
||
|
|
active_hysteresis = <0 0 0 0 (-3000)
|
||
|
|
(-4000) (-4000) 0 0 0>;
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
|
||
|
|
pwm-fan {
|
||
|
|
compatible = "pwm-fan";
|
||
|
|
status = "okay";
|
||
|
|
#pwm-cells = <1>;
|
||
|
|
pwms = <&tegra_pwm4 0 45334>;
|
||
|
|
shared_data = <&pwm_fan_shared_data>;
|
||
|
|
profiles {
|
||
|
|
default = "tmargin";
|
||
|
|
quiet {
|
||
|
|
state_cap = <8>;
|
||
|
|
active_pwm = <0 60 90 120 150 180 210 240 255 255>;
|
||
|
|
};
|
||
|
|
cool {
|
||
|
|
state_cap = <4>;
|
||
|
|
active_pwm = <0 77 120 160 255 255 255 255 255 255>;
|
||
|
|
};
|
||
|
|
tmargin {
|
||
|
|
state_cap = <0>;
|
||
|
|
active_pwm = <255 255 240 210 180 150 120 90 60 0>;
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
|