Re: [PATCH] Intel Manageability Engine Interface driver

[Andrew Morton <akpm@linux-foundation.org>]

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.