Option for custom CPU Fan curve

[flo-at-work]

Hello and thanks for your great work,

I would like to know if it's possible to implement a custom fan curve for the CPU fan. I'm using YogaSMC on a Thinkpad X250 and everything is working very well.
I can manage the fan speed manually or set it to automatic.

But I found that the original fan curve is not really optimal on my system so I added this SSDT method here, the method is commented out in the file, it's called FCPU (at the end of the file):
https://github.com/qwerty12/Hackintosh/blob/c83d4c1237f7fcd96825974d5cf63e9e7ff53a84/Lenovo-ThinkPad-T450/SSDTs/SSDT-BATT.dsl

Then I have to load RehabMan's ACPIPoller kext to make it work, then the fan curve works as I set it in the SSDT patch.
But then, even if YogaSMC is still able to read the speed correctly, I cannot change manually the fan speed anymore.

So I would like to know if there is a way to implement or make this method of custom fan curve to work by keeping in YogaSMC the ability to control the fan.

Thanks a lot!

[flo-at-work]

So to go a bit further in adjusting the fan curve for the Thinkpad X250, I managed to create an SSDT file containing this code:

/*
 * Intel ACPI Component Architecture
 * AML/ASL+ Disassembler version 20180427 (64-bit version)(RM)
 * Copyright (c) 2000 - 2018 Intel Corporation
 * 
 * Disassembling to non-symbolic legacy ASL operators
 *
 * Disassembly of iASL6p0CP6.aml, Sat Mar 30 15:39:28 2024
 *
 * Original Table Header:
 *     Signature        "SSDT"
 *     Length           0x000001B5 (437)
 *     Revision         0x02
 *     Checksum         0x95
 *     OEM ID           "T450S"
 *     OEM Table ID     "_FAN"
 *     OEM Revision     0x00000000 (0)
 *     Compiler ID      "INTL"
 *     Compiler Version 0x20180427 (538444839)
 */
DefinitionBlock ("", "SSDT", 2, "T450S", "_FAN", 0x00000000)
{
    External (_SB_.PCI0.LPC_.EC__, DeviceObj)    // (from opcode)
    External (_SB_.PCI0.LPC_.EC__.HFSP, FieldUnitObj)    // (from opcode)
    External (_SB_.PCI0.LPC_.EC__.TMP0, FieldUnitObj)    // (from opcode)

    Scope (\_SB.PCI0.LPC.EC)
    {
        Device (SMCD)
        {
            Name (_HID, "FAN00000")  // _HID: Hardware ID
            Method (FCPU, 0, Serialized)
            {
                Store (\_SB.PCI0.LPC.EC.TMP0, Local0)
                If (LLessEqual (Local0, 0x32))
                {
                    Store (Zero, \_SB.PCI0.LPC.EC.HFSP)
                }

                If (LGreaterEqual (Local0, 0x4F))
                {
                    Store (0x40, \_SB.PCI0.LPC.EC.HFSP)
                }
                ElseIf (LGreaterEqual (Local0, 0x4B))
                {
                    Store (0x07, \_SB.PCI0.LPC.EC.HFSP)
                }
                ElseIf (LGreaterEqual (Local0, 0x46))
                {
                    Store (0x04, \_SB.PCI0.LPC.EC.HFSP)
                }
                ElseIf (LGreaterEqual (Local0, 0x43))
                {
                    Store (0x03, \_SB.PCI0.LPC.EC.HFSP)
                }
                ElseIf (LGreaterEqual (Local0, 0x3F))
                {
                    Store (0x02, \_SB.PCI0.LPC.EC.HFSP)
                }
                ElseIf (LGreaterEqual (Local0, 0x37))
                {
                    Store (One, \_SB.PCI0.LPC.EC.HFSP)
                }

                Return (One)
            }
        }
    }
}

Then I load it with OpenCore (before SSDT-BATX) including the Rehabman kext ACPIPoller. Like this the custom fan curve is applied. But the drawback is that I cannot control anymore the fan manually via YogaSMC (but I'm able to see to correct speed).

So the next question is:
Is it possible to implement this SSDT function without the need of ACPIPoller (which loads the method "FCPU" with _HID "FAN00000"), and keep a manual control via YogaSMC?

Thanks a lot!

[flo-at-work]

Alternatively I would like to know how to change the fan speed with "ioio". I manage to get the fan speed with the following command:ioio -s ThinkVPC ReadECName HFSP and sudo dmesg | grep YSMC
But I can't manage to change it. Does anyone knows how to do that?
Thanks!

[flo-at-work]

Ok I figured it out, the command to manually change the fan speed is this one:
ioio -s ThinkVPC FanSpeed [number]
Example: ioio -s ThinkVPC FanSpeed 0 for stopping the fan or 1 to 7 for the different fan levels or 132 (0x84) for auto

[flo-at-work]

Now I made a custom shell script like this (named FanControl.sh):

#!/bin/bash
CpuTemp=$(/usr/local/bin/iStats cpu temp --value-only | rev | cut -c 7- | rev)
if ((CpuTemp >= 0 && CpuTemp <= 60)); then
/usr/local/bin/ioio -s ThinkVPC FanSpeed 0
elif ((CpuTemp >= 60 && CpuTemp <= 65)); then
/usr/local/bin/ioio -s ThinkVPC FanSpeed 1
elif ((CpuTemp >= 65 && CpuTemp <= 70)); then
/usr/local/bin/ioio -s ThinkVPC FanSpeed 2
elif ((CpuTemp >= 70 && CpuTemp <= 80)); then
/usr/local/bin/ioio -s ThinkVPC FanSpeed 3
elif ((CpuTemp >= 80 && CpuTemp <= 85)); then
/usr/local/bin/ioio -s ThinkVPC FanSpeed 5
elif ((CpuTemp >= 85 && CpuTemp <= 100)); then
/usr/local/bin/ioio -s ThinkVPC FanSpeed 7
fi

With a LaunchAgent (some.name.plist in ~/Library/LaunchAgents/ ) like this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>KeepAlive</key>
	<true/>
	<key>Label</key>
	<string>com.thinkpad.fancontrol</string>
	<key>Program</key>
	<string>/Users/name/path-to-the-script/FanControl.sh</string>
	<key>RunAtLoad</key>
	<true/>
	<key>StandardErrorPath</key>
	<string>/Users/name/path-to-the-script-folder/FanControlErrors.log</string>
	<key>StandardOutPath</key>
	<string>/Users/name/path-to-the-script-folder/FanControlOut.log</string>
	<key>StartInterval</key>
	<integer>4</integer>
</dict>
</plist>

So now I have an automatic fan control with a custom defined curve! For information I installed the program "iStats" with homebrew to get the CPU temp. So I can get rid of my previous SSDT patch and the ACPIPoller kext.