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From: Dylanger Daly <dylanger@thegrail.co>
To: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Dylanger Daly <dylanger@thegrail.co>,
	xen-devel@lists.xenproject.org, Jan Beulich <jbeulich@suse.com>,
	xen-devel@lists.xen.org
Subject: Re: [PATCH] Add Undervolt MSRs to wrmsr function.
Date: Thu, 18 Apr 2019 12:54:21 +0100	[thread overview]
Message-ID: <CANJ4vQ3TpPpqoiP5uXXVXjjUCkzwKYGTztCe2g34s_EUy2ghig@mail.gmail.com> (raw)
In-Reply-To: <660adf6f-a574-d1cb-44a3-871b8d076a54@citrix.com>

I'm running an i7-8550U on a Huawei Matebook X Pro. Running Qubes OS I
used to idle ~60C, with these MSRs enabled, I've been able to get
stable ~45-55C.

I'm not too sure, but I think it was reverse engineered from Intel's
XTU Tool. Perhaps it's behind NDAs? I'm not too sure

MSR 150 is where you're applying the Undervolt Voltage Offsets.

On Thu, Apr 18, 2019 at 12:12 PM Andrew Cooper
<andrew.cooper3@citrix.com> wrote:
>
> On 18/04/2019 10:19, Dylanger Daly wrote:
> > No worries Andrew, it was my first patch, thank you for the response.
> >
> > It's based on Xen 4.8
> >
> > Dom0 should be controlling it, but I wasn't aware of the Security
> > implications.
> >
> > The scope isn't well documented:
> >  https://ressman.org/posts/2018-06-26-voltage-temperature-tdp-thinkpad/
> >
> > More experimental as it worked with my Laptop.
>
> Which CPU exactly?
>
> MSR_TEMPERATURE_TARGET is documented.  It has package scope, but the
> availability of certain fields is model specific (but consistent, at least).
>
> I can't find any documentation on MSR 150 at all.
>
> ~Andrew

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

WARNING: multiple messages have this Message-ID (diff)
From: Dylanger Daly <dylanger@thegrail.co>
To: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Dylanger Daly <dylanger@thegrail.co>,
	xen-devel@lists.xenproject.org, Jan Beulich <jbeulich@suse.com>,
	xen-devel@lists.xen.org
Subject: Re: [Xen-devel] [PATCH] Add Undervolt MSRs to wrmsr function.
Date: Thu, 18 Apr 2019 12:54:21 +0100	[thread overview]
Message-ID: <CANJ4vQ3TpPpqoiP5uXXVXjjUCkzwKYGTztCe2g34s_EUy2ghig@mail.gmail.com> (raw)
Message-ID: <20190418115421.SilLKwNBih9CxDSFAQ1NcajkDF4U_VtfOv1nCudhZG4@z> (raw)
In-Reply-To: <660adf6f-a574-d1cb-44a3-871b8d076a54@citrix.com>

I'm running an i7-8550U on a Huawei Matebook X Pro. Running Qubes OS I
used to idle ~60C, with these MSRs enabled, I've been able to get
stable ~45-55C.

I'm not too sure, but I think it was reverse engineered from Intel's
XTU Tool. Perhaps it's behind NDAs? I'm not too sure

MSR 150 is where you're applying the Undervolt Voltage Offsets.

On Thu, Apr 18, 2019 at 12:12 PM Andrew Cooper
<andrew.cooper3@citrix.com> wrote:
>
> On 18/04/2019 10:19, Dylanger Daly wrote:
> > No worries Andrew, it was my first patch, thank you for the response.
> >
> > It's based on Xen 4.8
> >
> > Dom0 should be controlling it, but I wasn't aware of the Security
> > implications.
> >
> > The scope isn't well documented:
> >  https://ressman.org/posts/2018-06-26-voltage-temperature-tdp-thinkpad/
> >
> > More experimental as it worked with my Laptop.
>
> Which CPU exactly?
>
> MSR_TEMPERATURE_TARGET is documented.  It has package scope, but the
> availability of certain fields is model specific (but consistent, at least).
>
> I can't find any documentation on MSR 150 at all.
>
> ~Andrew

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

  reply	other threads:[~2019-04-18 11:54 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-18  8:56 [PATCH] Add Undervolt MSRs to wrmsr function Dylanger Daly
2019-04-18  8:56 ` [Xen-devel] " Dylanger Daly
2019-04-18  9:09 ` Andrew Cooper
2019-04-18  9:09   ` [Xen-devel] " Andrew Cooper
2019-04-18  9:19   ` Dylanger Daly
2019-04-18  9:19     ` [Xen-devel] " Dylanger Daly
2019-04-18 11:12     ` Andrew Cooper
2019-04-18 11:12       ` [Xen-devel] " Andrew Cooper
2019-04-18 11:54       ` Dylanger Daly [this message]
2019-04-18 11:54         ` Dylanger Daly

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