Re: [PATCH v2 1/3] PCI: Add check for CXL Secondary Bus Reset

Lukas Wunner
2024-04-04T09:02:18Z

On Wed, Apr 03, 2024 at 03:44:41PM +0100, Jonathan Cameron wrote:
> > Bjorn Helgaas wrote:
> > > FWIW, I pinged administration@pcisig.com and got the response that
> > > "1E98h is not a VID in our system, but 1E98 has already been reserved
> > > by CXL."
> > >
> > > I wish there were a clearer public statement of this reservation, but
> > > I interpret the response to mean that CXL is not a "Vendor", maybe due
> > > to some strict definition of "Vendor," but that PCI-SIG will not
> > > assign 0x1e98 to any other vendor.
> > >
> > > So IMO we should add "#define PCI_VENDOR_ID_CXL 0x1e98" so that if we
> > > ever *do* see such an assignment, we'll be more likely to flag it as
> > > an issue.
>
> Sorry for late entry on this discussion and I'll be careful what I say
> on the history.
>
> As you've guessed it was "entertaining" and for FWIW that text occurs
> in other consortium specs (some predate CXL).
>
> It's reserved with agreement from the PCI SIG for a strictly defined set
> of purposes that does not correspond to those allowed for a normal ID
> granted to a vendor member. As you say CXL isn't a vendor (don't ask
> how DMTF got a vendor ID - 0x1AB4).
>
> Hence the naming gymnastics and vague answers to avoid any chance of
> lawyers getting involved :(

Hm, I'm wondering if avoiding the term "vendor" with something like

#define PCI_CONSORTIUM_ID_CXL 0x1e98

would assuage the angst of a legal misstep? ;)