Re: [PATCH v11] drm/xe/vsec: Support BMG devices

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Wed, Aug 14, 2024 at 08:47:28PM +0000, Ruhl, Michael J wrote:
> > -----Original Message-----
> > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > Sent: Wednesday, August 14, 2024 2:41 PM
> > On Wed, Aug 14, 2024 at 04:49:05PM +0000, Ruhl, Michael J wrote:
> > > > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > > > Sent: Wednesday, August 14, 2024 9:56 AM On Tue, Aug 13, 2024 at
> > > > 02:29:27PM +0000, Ruhl, Michael J wrote:
> > > > > > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > > > > > Sent: Tuesday, August 13, 2024 10:11 AM On Mon, Aug 12, 2024 at
> > > > > > 04:04:22PM -0400, Michael J. Ruhl wrote:

...

> > > > > > > +#define BMG_DEVICE_ID 0xE2F8
> > > > > >
> > > > > > Is this defined in any specification? I mean is the format the
> > > > > > same as PCI device ID?
> > > > >
> > > > > I think that this is defined in BMG PMT yaml definition.  It is
> > > > > provide in the PMT discovery data, so it is defined by the specific device.
> > > >
> > > > Is there any documentation / specification about this?
> > > > Can it be UUID or 64-bit number or other format?
> > > > _Where_ is this being specified?
> > >
> > > The GUID is defined by the YAML file associated with the PMT device.
> > > In this case 16 bits are a device ID.
> > >
> > > From the cover letter of the PMT patch set (Intel Platform Monitoring
> > Technology):
> > >
> > > -
> > > The GUID uniquely identifies the register space of any monitor data
> > > exposed by the capability. The GUID is associated with an XML file
> > > from the vendor that describes the mapping of the register space along
> > > with properties of the monitor data.
> > > --
> > >
> > > I was told that this was the value to use for this specific device/feature.
> > >
> > > It is specified internally.  Not sure if there is any "documentation"
> > > available beyond that.
> > 
> > The YAML is *not* the specification. Do we have one that I can access to?
> > And I asked not about GUID, I asked about ID.
> 
> Andy,
> 
> For the BMG device, the device ID is defined as part PMT GUID, and 
> will be defined by the BMG PMT YAML specification.
> 
> So this is a vendor defined value.

Okay, thank you for clarification.

> Need to do some testing, and then I will re-post the patch.

-- 
With Best Regards,
Andy Shevchenko