04b_FanQuiet.txt

#Maintained by: RehabMan for: HP Probook 4x30s/4x40s
# 04b_FanQuiet.txt

#
# This fan patch provides enhanced fan control.  It does so by tricking
# the system into thinking that the laptop is arbitrarily cool, such 
# that it can override the default behavior and have complete control
# over the fan.
#
# More information on how this works is available at:
# http://www.tonymacx86.com/hp-probook/72043-new-fan-control-dsdt-silent-fan-higher-temps.html
#

# add fan readings and fan control
into device label SMCD remove_entry;
into definitionblock code_regex . insert
begin
Device (SMCD)\n
{\n
    Name (_HID, "FAN00000") // _HID: Hardware ID\n
// ACPISensors.kext configuration\n
    Name (TACH, Package()\n
    {\n
        "System Fan", "FAN0",\n
    })\n
    Name (TEMP, Package()\n
    {\n
        "CPU Heatsink", "TCPU",\n
        "Ambient", "TAMB",\n
        //"Mainboard", "TSYS",\n
        //"CPU Proximity", "TCPP",\n
    })\n
// Actual methods to implement fan/temp readings/control\n
    Method (FAN0, 0, Serialized)\n
    {\n
        Store (\_SB.PCI0.LPCB.EC0.FRDC, Local0)
        If (Local0) { Divide (Add(0x3C000, ShiftRight(Local0,1)), Local0,, Local0) }
		If (LEqual (0x03C4, Local0)) { Return (Zero) }\n
        Return (Local0)\n
    }\n
    Method (TCPU, 0, Serialized)\n
    {\n
        Acquire (\_SB.PCI0.LPCB.EC0.ECMX, 0xFFFF)\n
        Store (1, \_SB.PCI0.LPCB.EC0.CRZN)\n
        Store (\_SB.PCI0.LPCB.EC0.DTMP, Local0)\n
        Release (\_SB.PCI0.LPCB.EC0.ECMX)\n
        Return (Local0)\n
    }\n
	Method (TAMB, 0, Serialized)
	{\n
        Acquire (\_SB.PCI0.LPCB.EC0.ECMX, 0xFFFF)\n
        Store (4, \_SB.PCI0.LPCB.EC0.CRZN)\n
        Store (\_SB.PCI0.LPCB.EC0.TEMP, Local0)\n
        Release (\_SB.PCI0.LPCB.EC0.ECMX)\n
        Return (Local0)\n
	}\n
// Fan Control Table (pairs of temp, fan control byte)\n
	Name (FTAB, Buffer()\n
	{\n
		70, 255, 	// 255 is off (really auto, but at low temp it is off)\n
		73, 128, 	// 128 is slowest speed\n
		77, 82,\n
		82, 74,\n
		85, 59,\n
		90, 49,\n
		0xFF, 0 	// last entry must be 0xFF, 0 is max fan speed\n
	})\n
// Table to keep track of past temperatures (to track average)\n
	Name (FHST, Buffer(16) { 0x0, 0, 0, 0, 0x0, 0, 0, 0, 0x0, 0, 0, 0, 0x0, 0, 0, 0 })\n
	Name (FIDX, Zero) 	// current index in buffer above\n
	Name (FNUM, Zero) 	// number of entries in above buffer to count in avg\n
	Name (FSUM, Zero) 	// current sum of entries in buffer\n
// Keeps track of last fan speed set, and counter to set new one\n
	Name (FLST, 0xFF)	// last index for fan control\n
	Name (FCNT, 0)		// count of times it has been "wrong", 0 means no counter\n
	Name (FCTU, 20)		// timeout for changes (fan rpm going up)\n
	Name (FCTD, 40)		// timeout for changes (fan rpm going down)\n
    \n
// Fan control for CPU -- expects to be evaluated 1-per second\n
	Method (FCPU, 0, Serialized)\n
	{\n
		Acquire (\_SB.PCI0.LPCB.EC0.ECMX, 0xFFFF)\n
        \n
	// setup fake temperature (this is the key to controlling the fan!)\n
		Store (1, \_SB.PCI0.LPCB.EC0.CRZN)  // select CPU temp\n
		Store (31, \_SB.PCI0.LPCB.EC0.TEMP) // write fake value there (31C)\n
        \n
	// get current temp into Local0 for eventual return\n
		// Note: reading from DTMP here instead of TEMP because we wrote\n
		//  a fake temp to TEMP to trick the system into running the fan\n
		//	at a lower speed than it otherwise would.\n
		Store (1, \_SB.PCI0.LPCB.EC0.CRZN)  // select CPU temp\n
		Store (\_SB.PCI0.LPCB.EC0.DTMP, Local0) // Local0 is current temp\n
        \n
    // calculate average temperature\n
		Add (Local0, FSUM, Local1)\n
		Store (FIDX, Local2)\n
		Subtract (Local1, DerefOf (Index (FHST, Local2)), Local1)\n
		Store (Local0, Index (FHST, Local2))\n
		Store (Local1, FSUM)  // Local1 is new sum\n
        \n
		// adjust current index into temp table\n
		Increment (Local2)\n
		if (LGreaterEqual (Local2, SizeOf(FHST))) { Store (0, Local2) }\n
		Store (Local2, FIDX)\n
		// adjust total items collected in temp table\n
		Store (FNUM, Local2)\n
		if (LNotEqual (Local2, SizeOf (FHST)))\n
		{\n
			Increment (Local2)\n
			Store (Local2, FNUM)\n
		}\n
        \n
		// Local1 is new sum, Local2 is number of entries in sum\n
		Divide (Local1, Local2,, Local0)  // Local0 is now average temp\n
        \n
	// table based search (use avg temperature to search)\n
		if (LGreater (Local0, 255)) { Store (255, Local0) }\n
		Store (Zero, Local2)\n
		while (LGreater (Local0, DerefOf (Index (FTAB, Local2)))) { Add (Local2, 2, Local2) }\n
        \n
	// calculate difference between current and found index\n
		if (LGreater (Local2, FLST))\n
		{\n
			Subtract(Local2, FLST, Local1)\n
			Store(FCTU, Local4)\n
		}\n
		Else\n
		{\n
			Subtract(FLST, Local2, Local1)\n
			Store(FCTD, Local4)\n
		}\n
        \n
	// set new fan speed, if necessary\n
		if (LEqual (Local1, 0))\n
		{\n
			// no difference, so leave current fan speed and reset count\n
			Store (0, FCNT)\n
		}\n
		Else\n
		{\n
			// there is a difference, start/continue process of changing fan\n
			Store (FCNT, Local3)\n
			Increment (Local3)\n
			Store (Local3, FCNT)\n
            \n
			// how long to wait depends on how big the difference\n
			// 20 secs if diff is 2, 5 secs if diff is 4, etc.\n
			Divide (ShiftLeft (Local4, 1), Local1,, Local1)\n
			if (LGreaterEqual (Local3, Local1))\n
			{\n
				// timeout expired, so set new fan speed\n
				Store (Local2, FLST)\n
				Increment (Local2)\n
				Store (DerefOf (Index (FTAB, Local2)), \_SB.PCI0.LPCB.EC0.FTGC)\n
				Store (0, FCNT)\n
			}\n
		}\n
        \n
		Release (\_SB.PCI0.LPCB.EC0.ECMX)\n
		return (Local0)  // returns average temp\n
	}\n
// for debugging fan control\n
	Method (TCPP, 0, Serialized)  // Average temp\n
	{\n
		Store (FNUM, Local0)\n
		if (LNotEqual (Local0, 0))\n
		{\n
			Store (FSUM, Local1)\n
			Divide (Local1, Local0,, Local0)\n
		}\n
		Return (Local0)\n
	}\n
	Method (TSYS, 0, Serialized)  // fan counter\n
	{\n
		Return (FCNT)\n
	}\n
}\n
end;