cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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aspeed-pwm-tacho.txt (2379B)

      1ASPEED AST2400/AST2500 PWM and Fan Tacho controller device driver
      2
      3The ASPEED PWM controller can support upto 8 PWM outputs. The ASPEED Fan Tacho
      4controller can support upto 16 Fan tachometer inputs.
      5
      6There can be upto 8 fans supported. Each fan can have one PWM output and
      7one/two Fan tach inputs.
      8
      9Required properties for pwm-tacho node:
     10- #address-cells : should be 1.
     11
     12- #size-cells : should be 1.
     13
     14- #cooling-cells: should be 2.
     15
     16- reg : address and length of the register set for the device.
     17
     18- pinctrl-names : a pinctrl state named "default" must be defined.
     19
     20- pinctrl-0 : phandle referencing pin configuration of the PWM ports.
     21
     22- compatible : should be "aspeed,ast2400-pwm-tacho" for AST2400 and
     23	       "aspeed,ast2500-pwm-tacho" for AST2500.
     24
     25- clocks : phandle to clock provider with the clock number in the second cell
     26
     27- resets : phandle to reset controller with the reset number in the second cell
     28
     29fan subnode format:
     30===================
     31Under fan subnode there can upto 8 child nodes, with each child node
     32representing a fan. If there are 8 fans each fan can have one PWM port and
     33one/two Fan tach inputs.
     34For PWM port can be configured cooling-levels to create cooling device.
     35Cooling device could be bound to a thermal zone for the thermal control.
     36
     37Required properties for each child node:
     38- reg : should specify PWM source port.
     39	integer value in the range 0 to 7 with 0 indicating PWM port A and
     40	7 indicating PWM port H.
     41
     42- cooling-levels: PWM duty cycle values in a range from 0 to 255
     43                  which correspond to thermal cooling states.
     44
     45- aspeed,fan-tach-ch : should specify the Fan tach input channel.
     46                integer value in the range 0 through 15, with 0 indicating
     47		Fan tach channel 0 and 15 indicating Fan tach channel 15.
     48		Atleast one Fan tach input channel is required.
     49
     50Examples:
     51
     52pwm_tacho: pwmtachocontroller@1e786000 {
     53	#address-cells = <1>;
     54	#size-cells = <1>;
     55	#cooling-cells = <2>;
     56	reg = <0x1E786000 0x1000>;
     57	compatible = "aspeed,ast2500-pwm-tacho";
     58	clocks = <&syscon ASPEED_CLK_APB>;
     59	resets = <&syscon ASPEED_RESET_PWM>;
     60	pinctrl-names = "default";
     61	pinctrl-0 = <&pinctrl_pwm0_default &pinctrl_pwm1_default>;
     62
     63	fan@0 {
     64		reg = <0x00>;
     65		cooling-levels = /bits/ 8 <125 151 177 203 229 255>;
     66		aspeed,fan-tach-ch = /bits/ 8 <0x00>;
     67	};
     68
     69	fan@1 {
     70		reg = <0x01>;
     71		aspeed,fan-tach-ch = /bits/ 8 <0x01 0x02>;
     72	};
     73};