Re: [PATCH 7/7] ocxl: Use pci core's DVSEC functionality

[Frederic Barrat <fbarrat@linux.ibm.com>]

On 22/09/2021 02:44, Dan Williams wrote:
> On Tue, Sep 21, 2021 at 3:05 PM Ben Widawsky <ben.widawsky@intel.com> wrote:
>>
>> Reduce maintenance burden of DVSEC query implementation by using the
>> centralized PCI core implementation.
>>
>> Cc: linuxppc-dev@lists.ozlabs.org
>> Cc: Frederic Barrat <fbarrat@linux.ibm.com>
>> Cc: Andrew Donnellan <ajd@linux.ibm.com>
>> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
>> ---
>>   drivers/misc/ocxl/config.c | 13 +------------
>>   1 file changed, 1 insertion(+), 12 deletions(-)
>>
>> diff --git a/drivers/misc/ocxl/config.c b/drivers/misc/ocxl/config.c
>> index a68738f38252..e401a51596b9 100644
>> --- a/drivers/misc/ocxl/config.c
>> +++ b/drivers/misc/ocxl/config.c
>> @@ -33,18 +33,7 @@
>>
>>   static int find_dvsec(struct pci_dev *dev, int dvsec_id)
>>   {
>> -       int vsec = 0;
>> -       u16 vendor, id;
>> -
>> -       while ((vsec = pci_find_next_ext_capability(dev, vsec,
>> -                                                   OCXL_EXT_CAP_ID_DVSEC))) {
>> -               pci_read_config_word(dev, vsec + OCXL_DVSEC_VENDOR_OFFSET,
>> -                               &vendor);
>> -               pci_read_config_word(dev, vsec + OCXL_DVSEC_ID_OFFSET, &id);
>> -               if (vendor == PCI_VENDOR_ID_IBM && id == dvsec_id)
>> -                       return vsec;
>> -       }
>> -       return 0;
>> +       return pci_find_dvsec_capability(dev, PCI_VENDOR_ID_IBM, dvsec_id);
>>   }


That looks fine, thanks for spotting it. You can add this for the next 
revision:
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>



> 
> What about:
> 
> arch/powerpc/platforms/powernv/ocxl.c::find_dvsec_from_pos()
> 
> ...?  With that converted the redundant definitions below:
> 
> OCXL_EXT_CAP_ID_DVSEC
> OCXL_DVSEC_VENDOR_OFFSET
> OCXL_DVSEC_ID_OFFSET
> 
> ...can be cleaned up in favor of the core definitions.


That would be great. Are you guys willing to do it? If not, I could have 
a follow-on patch, if I don't forget :-)

Thanks,

   Fred