RE: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space accessors against platfrom specific ECAM quirks

From: Gabriele Paoloni
Date: Mon Jun 13 2016 - 10:30:17 EST


Hi Sinan

> -----Original Message-----
> From: Sinan Kaya [mailto:okaya@xxxxxxxxxxxxxx]
> Sent: 13 June 2016 15:03
> To: Gabriele Paoloni; liudongdong (C); helgaas@xxxxxxxxxx;
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> (Charles); Linuxarm
> Subject: Re: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space
> accessors against platfrom specific ECAM quirks
>
> On 6/13/2016 9:54 AM, Gabriele Paoloni wrote:
> > As you can see here Liudongdong has replaced oem_revision with
> > oem_table_id.
> >
> > Now it seems that there are some platforms that have already shipped
> > using a matching based on the oem_revision (right Jon?)
> >
> > However I guess that if in FW they have defined oem_table_id properly
> > they should be able to use this mechanism without needing to a FW
> update.
> >
> > Can these vendors confirm this?
> >
> > Tomasz do you think this can work for Cavium Thunder?
> >
> > Thanks
> >
> > Gab
>
> Why not have all three of them?
>
> The initial approach was OEM id and revision id.
>
> Jeff Hugo indicated that addition (not removing any other fields) of
> table id
> would make more sense.

Mmm from last email of Jeff Hugo on "[RFC PATCH 1/3] pci, acpi: Match
PCI config space accessors against platfrom specific ECAM quirks."

I quote:

"Using the OEM revision
field does not seem to be appropriate since these are different
platforms and the revision field appears to be for the purpose of
tracking differences within a single platform. Therefore, Cov is
proposing using the OEM table id as a mechanism to distinguish
platform A (needs quirk applied) vs platform B (no quirks) from the
same OEM."

So it looks to me that he pointed out that using the OEM revision field
is wrong...and this is why I have asked if replacing it with the table
id can work for other vendors....

Thanks

Gab


>
> --
> Sinan Kaya
> Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center,
> Inc.
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
> Linux Foundation Collaborative Project