On 6/13/2016 9:12 AM, okaya@xxxxxxxxxxxxxx wrote:
On 2016-06-13 10:29, Gabriele Paoloni wrote:
Hi Sinan
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From: Sinan Kaya [mailto:okaya@xxxxxxxxxxxxxx]
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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
I had an internal discussion with jeff and cov before posting on the
maillist.
I think there is missing info in the email.
Usage of oem id + table id + revision is ok.
Usage of oem id + revision is not ok as one oem can build multiple chips
with the same oem id and revision id but different table id. Otherwise,
we can run out of revisions very quickly.
Agreed.
I'm sorry for the confusion. My intent was to point out that revision
alone appeared insufficient to address all the identified problems, but
I believe there is still a case for using revision. Table id is useful
for differentiating between platforms/chips. Revision is useful for
differentiation between different versions of a single platform/chip
assuming the silicon is respun or some other fix is applied. Both solve
different scenarios, and I'm not aware of a reason why they could not be
used together to solve all currently identified cases.
--
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
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--
Jeffrey Hugo
Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
Linux Foundation Collaborative Project
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