Re: [PATCH V2 2/4] vDPA/ifcvf: enable Intel C5000X-PL virtio-net for vDPA

["Zhu, Lingshan" <lingshan.zhu@intel.com>]

On 3/9/2021 10:23 AM, Jason Wang wrote:
>
> On 2021/3/8 4:35 下午, Zhu Lingshan wrote:
>> This commit enabled Intel FPGA SmartNIC C5000X-PL virtio-net
>> for vDPA
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vdpa/ifcvf/ifcvf_base.h | 5 +++++
>>   drivers/vdpa/ifcvf/ifcvf_main.c | 5 +++++
>>   2 files changed, 10 insertions(+)
>>
>> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h 
>> b/drivers/vdpa/ifcvf/ifcvf_base.h
>> index 64696d63fe07..75d9a8052039 100644
>> --- a/drivers/vdpa/ifcvf/ifcvf_base.h
>> +++ b/drivers/vdpa/ifcvf/ifcvf_base.h
>> @@ -23,6 +23,11 @@
>>   #define IFCVF_SUBSYS_VENDOR_ID    0x8086
>>   #define IFCVF_SUBSYS_DEVICE_ID    0x001A
>>   +#define C5000X_PL_VENDOR_ID        0x1AF4
>> +#define C5000X_PL_DEVICE_ID        0x1000
>> +#define C5000X_PL_SUBSYS_VENDOR_ID    0x8086
>> +#define C5000X_PL_SUBSYS_DEVICE_ID    0x0001
>
>
> I just notice that the device is a transtitional one. Any reason for 
> doing this?
>
> Note that IFCVF is a moden device anyhow (0x1041). Supporting legacy 
> drive may bring many issues (e.g the definition is non-nomartive). One 
> example is the support of VIRTIO_F_IOMMU_PLATFORM, legacy driver may 
> assume the device can bypass IOMMU.
>
> Thanks
Hi Jason,

This device will support virtio1.0 by default, so has 
VIRTIO_F_IOMMU_PLATFORM by default. Transitional device gives the 
software a chance to fall back to virtio 0.95.
ifcvf drives this device in virtio 1.0 mode, set features 
VIRTIO_F_IOMMU_PLATFORM successfully.

Thanks,
Zhu Lingshan
>
>
>> +
>>   #define IFCVF_SUPPORTED_FEATURES \
>>           ((1ULL << VIRTIO_NET_F_MAC)            | \
>>            (1ULL << VIRTIO_F_ANY_LAYOUT)            | \
>> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c 
>> b/drivers/vdpa/ifcvf/ifcvf_main.c
>> index e501ee07de17..26a2dab7ca66 100644
>> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
>> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
>> @@ -484,6 +484,11 @@ static struct pci_device_id ifcvf_pci_ids[] = {
>>           IFCVF_DEVICE_ID,
>>           IFCVF_SUBSYS_VENDOR_ID,
>>           IFCVF_SUBSYS_DEVICE_ID) },
>> +    { PCI_DEVICE_SUB(C5000X_PL_VENDOR_ID,
>> +             C5000X_PL_DEVICE_ID,
>> +             C5000X_PL_SUBSYS_VENDOR_ID,
>> +             C5000X_PL_SUBSYS_DEVICE_ID) },
>> +
>>       { 0 },
>>   };
>>   MODULE_DEVICE_TABLE(pci, ifcvf_pci_ids);
>