Re: [PATCH -v3 3/3] PCI,pciehp: use PCIe DSN to identify device changeduring suspend

From: Yijing Wang
Date: Tue Jul 30 2013 - 00:12:54 EST


>>
>> Hi Bjorn,
>> I'm reworking this patch, but found some strange info about vpd serial number.
>> I have two x86 machines, they almost have the same hardware topology. But by lspci,
>> I found two different Broadcom BCM5709 NIC in different machine have the same vpd serial
>> number. If this is normal, vpd serial number seems to be useless for identify device change.
>
> I wouldn't say it's completely useless. If the VPD serial number
> changes, we can be pretty confident that the card has changed. It's
> just that if the VPD serial number is unchanged, we might incorrectly
> assume it's the same device.
>
> But we currently *always* assume it's the same device, since we don't
> look at serial numbers at all. If we can detect some changes, that
> should be an improvement over what we have today even though it's not
> perfect.

Hmmm, Yes, different VPD serial number must comes from different device.
Although the same serial number maybe not the same device.

I will send out the new version patchset soon.

Thanks!
Yijing.

>
>> The first machine:
>> linux:/home/yijing # lspci -vvv -s 0000:01:00.0
>> 01:00.0 Ethernet controller: Broadcom Corporation NetXtreme II BCM5709 Gigabit Ethernet (rev 20)
>> Subsystem: Broadcom Corporation NetXtreme II BCM5709 Gigabit Ethernet
>> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
>> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
>> Latency: 0, Cache Line Size: 256 bytes
>> Interrupt: pin A routed to IRQ 28
>> Region 0: Memory at c0000000 (64-bit, non-prefetchable) [size=32M]
>> Capabilities: [48] Power Management version 3
>> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
>> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=1 PME-
>> Capabilities: [50] Vital Product Data
>> Product Name: Broadcom NetXtreme II Ethernet Controller
>> Read-only fields:
>> [PN] Part number: BCM95706A0
>> [EC] Engineering changes: 220197-2
>> [SN] Serial number: 0123456789
>> [MN] Manufacture ID: 31 34 65 34
>> [RV] Reserved: checksum good, 31 byte(s) reserved
>> End
>> Capabilities: [58] MSI: Enable- Count=1/16 Maskable- 64bit+
>> Address: 0000000000000000 Data: 0000
>> ..............[snip]...................
>>
>> The second machine:
>> linux-suse-vmdq:~/pciutils-3.2.0 # ./lspci -vvv -s 01:00.0
>> 01:00.0 Ethernet controller: Broadcom Corporation NetXtreme II BCM5709 Gigabit Ethernet (rev 20)
>> Subsystem: Broadcom Corporation NetXtreme II BCM5709 Gigabit Ethernet
>> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
>> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
>> Latency: 0, Cache Line Size: 256 bytes
>> Interrupt: pin A routed to IRQ 28
>> Region 0: Memory at f6000000 (64-bit, non-prefetchable) [size=32M]
>> Capabilities: [48] Power Management version 3
>> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
>> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=1 PME-
>> Capabilities: [50] Vital Product Data
>> Product Name: Broadcom NetXtreme II Ethernet Controller
>> Read-only fields:
>> [PN] Part number: BCM95706A0
>> [EC] Engineering changes: 220197-2
>> [SN] Serial number: 0123456789
>> [MN] Manufacture ID: 31 34 65 34
>> [RV] Reserved: checksum good, 31 byte(s) reserved
>> End
>> .......[snip]........
>>
>>
>>>
>>> Also, I think it's possible to use acpiphp for ExpressCard slots, and
>>> this patch doesn't help acpiphp detect card swaps. I don't see any
>>> mention of suspend/resume in acpiphp, so I don't know if it does
>>> anything at all to detect card changes while suspended. Maybe Rafael
>>> can shed some light?
>>>
>>> I put the first two patches on a pci/yijing-dsn-v3 branch while we
>>> work out the details of this one.
>>>
>>> Bjorn
>>>
>>>> } else if (!list_empty(&pbus->devices)) {
>>>> pciehp_disable_slot(slot);
>>>> }
>>>> --
>>>> 1.7.1
>>>>
>>>>
>>>
>>> .
>>>
>>
>>
>> --
>> Thanks!
>> Yijing
>>
>
> .
>


--
Thanks!
Yijing

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