acpi thermal problem 'fix' (fwd)
George Wood
gwood at woodsite.net
Wed Apr 5 20:29:45 UTC 2006
my pc shuts down when cpu temp exceeds 60 C.
since 'hw.acpi.thermal.tz0._CRT' is read only, I can't reset
the value there.
The advice below, edit & recompile a dumped ASL, doesn't work for
me because the ASL will not compile.
Do I have any alternative other than completely disabling acpi?
George Wood
I found a discussion of this online where Nate Lawson said this advice
was correct:
Date: Thu, 23 Jun 2005 14:25:17 -0700
From: Nate Lawson <nate at root.org>
Subject: Re: Changing temperature threshold
(trimmed, full message attached)
Alexandre "Sunny" Kovalenko wrote:
>>When I try to raise hw.acpi.thermal.tz0._CRT to 85C (which is the
>>threshold in the BIOS setup) it doesn't work:
>>
>>bell# sysctl hw.acpi.thermal.tz0._CRT=3580 # 3580 tenths of
Kelvin=85C
>>sysctl: oid 'hw.acpi.thermal.tz0._CRT' is read only
...
> One of the ways to deal with that would be to dump your ASL (see
> Handbook for guidance), find lines which look like:
> Method (_CRT, 0, NotSerialized)
> {
> Return (KELV (0x5d))
> }
> modify them to your liking, compile ASL and override it during boot
> (instructions on how to compile and override are in Handbook as well).
> Please, note that actual value returned is in the 1/10th of the degree
> of Kelvin. Function KELV above has following ASL code associated with
> it:
> Method (KELV, 1, NotSerialized)
> {
> Store (Arg0, Local1)
> Multiply (0x0A, Local1, Local1)
> Add (Local1, 0x0AAC, Local1)
> Return (Local1)
> }
> Thermal management chapter of the ACPI specification should provide you
> with ample explanation of what this is all about.
So I did as suggested, dumped th asl and looked for the _CRT method;
(the full .asl file is attached). Here's what I found:
Method (_CRT, 0, NotSerialized)
{
Return (TRPC)
}
the only reference I found to TRPC was:
DefinitionBlock ("DSDT.aml", "DSDT", 1, "KT400 ", "AWRDACPI", 4096)
{
...
OperationRegion (TEMM, SystemMemory, 0x000FF810, 0x0C)
Field (TEMM, WordAcc, NoLock, Preserve)
{
TP1H, 16,
TP1L, 16,
TP2H, 16,
TP2L, 16,
TRPC, 16,
SENF, 16
}
...
}
so I figured I'd just hard code a corrected temperature into the
_CRT method, recompile the asl and override (per the handbook).
Before modifying the .asl, I decided to compile the dumped .asl so
I'd know what the 'normal' warnings were. Sadly, the compiler
dumped a pile of errors:
---------------- begin compiler output --------------
Intel ACPI Component Architecture
ASL Optimizing Compiler / AML Disassembler version 20041119 [Nov 3 2005]
Copyright (C) 2000 - 2004 Intel Corporation
Supports ACPI Specification Revision 2.0c
acpidump.asl 427: Method (\_WAK, 1, NotSerialized)
Warning 2026 - ^ Reserved method must return a value (_WAK)
acpidump.asl 470: Store (Local0, Local0)
Error 1013 - ^ Method local variable is not initialized (Local0)
acpidump.asl 478: Store (Local0, Local0)
Error 1013 - ^ Method local variable is not initialized (Local0)
acpidump.asl 2133: Method (STM, 0, Serialized)
Warning 2019 - ^ Not all control paths return a value (STM_)
acpidump.asl 3836: Store (Local0, Local0)
Error 1013 - ^ Method local variable is not initialized (Local0)
ASL Input: acpidump.asl - 4331 lines, 128623 bytes, 1697 keywords
Compilation complete. 3 Errors, 2 Warnings, 0 Remarks, 508 Optimizations
---------------- end of compiler output --------------
per your note, warnings might be ok but errors are going to
make things barf. I'm not attaching the full ASL file due to
its size, but I'll be happy to mail it to anyone interested.
I previously sent it to Nate.
Now what?
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Date: Thu, 23 Jun 2005 14:25:17 -0700
From: Nate Lawson <nate at root.org>
To: "Alexandre \"Sunny\" Kovalenko" <Alex.Kovalenko at verizon.net>
Cc: freebsd-acpi at freebsd.org, Matthew Flanagan <flanagan.matt at gmail.com>
Subject: Re: Changing temperature threshold
Message-ID: <42BB28BD.5080202 at root.org>
In-Reply-To: <1130426516.777.7.camel at RabbitsDen>
References: <7cd06a2d05062205331d03372c at mail.gmail.com> <7cd06a2d050623073452e3c3f9 at mail.gmail.com> <1130426516.777.7.camel at RabbitsDen>
Next in thread | Previous in thread | Raw E-Mail | Index | Archive | Help
Alexandre "Sunny" Kovalenko wrote:
>>When I try to raise hw.acpi.thermal.tz0._CRT to 85C (which is the
>>threshold in the BIOS setup) it doesn't work:
>>
>>bell# sysctl hw.acpi.thermal.tz0._CRT=3580 # 3580 tenths of Kelvin=85C
>>sysctl: oid 'hw.acpi.thermal.tz0._CRT' is read only
>>
>>Now, my question is: how do I change this value? I've read several
>>manpages (acpi(4), acpi_thermal(4), acpiconf(8), loader(8), and many
>>others) and checked the handbook, to no avail. Can anyone point me
>>to the right direction?
>
> One of the ways to deal with that would be to dump your ASL (see
> Handbook for guidance), find lines which look like:
> Method (_CRT, 0, NotSerialized)
> {
> Return (KELV (0x5d))
> }
> modify them to your liking, compile ASL and override it during boot
> (instructions on how to compile and override are in Handbook as well).
> Please, note that actual value returned is in the 1/10th of the degree
> of Kelvin. Function KELV above has following ASL code associated with
> it:
> Method (KELV, 1, NotSerialized)
> {
> Store (Arg0, Local1)
> Multiply (0x0A, Local1, Local1)
> Add (Local1, 0x0AAC, Local1)
> Return (Local1)
> }
> Thermal management chapter of the ACPI specification should provide you
> with ample explanation of what this is all about.
This explanation is correct. The reason why the sysctl is read-only is
because the values are supplied by the BIOS and are what the OEM thinks
are critical temperatures. However, we need a way to allow override in
the case of obviously wrong values like this. I'll probably change it
to allow overriding from the loader but be read-only in sysctl to avoid
accidental changes from users experimenting.
--
Nate
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ermal management chapter of the ACPI specification should provide you
> with ample explanation of what this is all about.
This explanation is correct. The reason why the sysctl is read-only is
because the values are supplied by the BIOS and are what the OEM thinks
are critical temperatures. However, we need a way to allow override in
the case of obviously wrong values like this. I'll probably change it
to allow overriding from the loader but be read-only in sysctl to avoid
accidental changes from users experimenting.
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