Re: [PATCH v1 7/7] fpga: dfl: pci: Add generic OFS PCI PID

[Tom Rix <trix@redhat.com>]

On 2/18/22 1:03 AM, Zhang, Tianfei wrote:
>
>> -----Original Message-----
>> From: Tom Rix <trix@redhat.com>
>> Sent: Wednesday, February 16, 2022 12:16 AM
>> To: Zhang, Tianfei <tianfei.zhang@intel.com>; Wu, Hao <hao.wu@intel.com>;
>> mdf@kernel.org; Xu, Yilun <yilun.xu@intel.com>; linux-fpga@vger.kernel.org;
>> linux-doc@vger.kernel.org; linux-kernel@vger.kernel.org
>> Cc: corbet@lwn.net; Matthew Gerlach <matthew.gerlach@linux.intel.com>
>> Subject: Re: [PATCH v1 7/7] fpga: dfl: pci: Add generic OFS PCI PID
>>
>>
>> On 2/14/22 3:26 AM, Tianfei zhang wrote:
>>> From: Matthew Gerlach <matthew.gerlach@linux.intel.com>
>>>
>>> Add the PCI product id for an Open FPGA Stack PCI card.
>> Is there a URL to the card ?
> This PCIe Device IDs have registered by Intel.
A URL is useful to introduce the board, Is there one ?
>
>>> Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
>>> Signed-off-by: Tianfei Zhang <tianfei.zhang@intel.com>
>>> ---
>>>    drivers/fpga/dfl-pci.c | 4 ++++
>>>    1 file changed, 4 insertions(+)
>>>
>>> diff --git a/drivers/fpga/dfl-pci.c b/drivers/fpga/dfl-pci.c index
>>> 83b604d6dbe6..cb2fbf3eb918 100644
>>> --- a/drivers/fpga/dfl-pci.c
>>> +++ b/drivers/fpga/dfl-pci.c
>>> @@ -76,12 +76,14 @@ static void cci_pci_free_irq(struct pci_dev *pcidev)
>>>    #define PCIE_DEVICE_ID_INTEL_PAC_D5005		0x0B2B
>>>    #define PCIE_DEVICE_ID_SILICOM_PAC_N5010	0x1000
>>>    #define PCIE_DEVICE_ID_SILICOM_PAC_N5011	0x1001
>>> +#define PCIE_DEVICE_ID_INTEL_OFS		0xbcce
>> INTEL_OFS is a generic name, pci id's map to specific cards
>>
>> Is there a more specific name for this card ?
> I think using INTEL_OFS is better, because INTEL_OFS is the Generic development platform can support multiple cards which using OFS specification,
> like Intel PAC N6000 card.

I would prefer something like PCIE_DEVICE_ID_INTEL_PAC_N6000 because it 
follows an existing pattern.  Make it easy on a developer, they will 
look at their board or box, see X and try to find something similar in 
the driver source.

To use OSF_ * the name needs a suffix to differentiate it from future 
cards that will also use ofs.

If this really is a generic id please explain in the doc patch how every 
future board with use this single id and how a driver could work around 
a hw problem in a specific board with a pci id covering multiple boards.

Tom

>
>> Tom
>>
>>>    /* VF Device */
>>>    #define PCIE_DEVICE_ID_VF_INT_5_X		0xBCBF
>>>    #define PCIE_DEVICE_ID_VF_INT_6_X		0xBCC1
>>>    #define PCIE_DEVICE_ID_VF_DSC_1_X		0x09C5
>>>    #define PCIE_DEVICE_ID_INTEL_PAC_D5005_VF	0x0B2C
>>> +#define PCIE_DEVICE_ID_INTEL_OFS_VF		0xbccf
>>>
>>>    static struct pci_device_id cci_pcie_id_tbl[] = {
>>>    	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_5_X),},
>> @@
>>> -95,6 +97,8 @@ static struct pci_device_id cci_pcie_id_tbl[] = {
>>>    	{PCI_DEVICE(PCI_VENDOR_ID_INTEL,
>> PCIE_DEVICE_ID_INTEL_PAC_D5005_VF),},
>>>    	{PCI_DEVICE(PCI_VENDOR_ID_SILICOM_DENMARK,
>> PCIE_DEVICE_ID_SILICOM_PAC_N5010),},
>>>    	{PCI_DEVICE(PCI_VENDOR_ID_SILICOM_DENMARK,
>>> PCIE_DEVICE_ID_SILICOM_PAC_N5011),},
>>> +	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_OFS),},
>>> +	{PCI_DEVICE(PCI_VENDOR_ID_INTEL,
>> PCIE_DEVICE_ID_INTEL_OFS_VF),},
>>>    	{0,}
>>>    };
>>>    MODULE_DEVICE_TABLE(pci, cci_pcie_id_tbl);