Re: [PATCH] Intel Manageability Engine Interface driver

Andrew Morton
2007-10-23T16:26:10Z

On Tue, 23 Oct 2007 09:31:07 -0400 Anas Nashif <nashif@linux.intel.com> wrote:

> Andrew,
>
> Thanks for the feedback.
>
> Andrew Morton wrote:
> > On Mon, 22 Oct 2007 13:22:38 -0400 Anas Nashif <nashif@linux.intel.com> wrote:
> >>
> >> The patch is large so I'm placing the diff on the web for download
> >> rather than attaching it here. Download:
> >>
> >> http://download.openamt.org/intel-MEI.diff
> >
> > Please get the patches mailed out somehow. Consider splitting the patch
> > up. I think you could send it as-is (200k will fit, I believe) but it's
> > rather too large to review effectively.
> >
> > The code looks good from a quick scan. Immediate impressions from a
> > quick scan, mainly trivia:
> >
>
> We will fix the issues below and send the revised patch to the list.
>
> >
> >
> > - Why does a new driver have "additional char device for legacy mode"?
> >
>
> It is not quite new. What is currently considered legacy was supported
> on Linux with a driver that was never submitted upstream (although it is
> open-source and available from e1000.sf.net).
> Some applications still use the legacy interface (KCS style) and have to
> be supported with the new driver as well.
>

It would be better to remove the lecacy mode support from the new driver
and to continue to ship a patch for those people who use the old interface.
They've been patching in the whole driver thus far so I assume all the
processes are already in place for this.

>
> > - The changelog could do with some expansion. What is "Intel(R)
> > Manageability Engine (ME) firmware"? Why do we want to include this code
> > in Linux? What value has it to our users, etc? Bascially: tell us more
> > stuff.
>
> The core hardware architecture of Intel Active Management Technology
> (Intel AMT) is resident in firmware. The micro-controller within the
> chipset's graphics and memory controller (MCH) hub houses the Management
> Engine (ME) firmware, which implements various services on behalf of
> management applications. Additionally, flash memory houses system BIOS,
> code used by the management engine, and a third-party data store (3PDS)
> that enables applications to store information as needed in non-volatile
> memory.
>
> Communication between the host OS and the ME is accomplished by means of
> the Intel Management Engine Interface (aka HECI: Host Embedded
> Controller Interface ). MEI is bi-directional, and either the host or
> Intel AMT firmware can initiate transactions.
>
> Some of the ME subsystems that can be access via MEI driver:
>
> - Intel(R) Quiet System Technology (QST) is implemented as a firmware
> subsystem that runs in the ME. Programs that wish to expose the
> health monitoring and fan speed control capabilities of Intel(R) QST
> will need to use the MEI driver to communicate with the ME sub-system.
> - ASF is the "Alert Standard Format" which is an DMTF manageability
> standard. It is implemented in the PC's hardware and firmware, and is
> managed from a remote console.
>
> Most recent Intel desktop chipsets have one or more of the above ME
> services. The MEI driver will make it possible to support the above
> features on Linux and provides applications access to the ME and it's
> features. The MEI drivers will also help bridge a current gap related to
> lm_sensors support on recent desktop chipsets.
>

I see, thanks. That would be a fine addition to the patch's changelog,
please.