Re: [PATCH 8/9] vfio/pci: export nvlink2 support into vendor vfio_pci drivers

[Alexey Kardashevskiy]

On 11/03/2021 00:02, Jason Gunthorpe wrote:
> On Wed, Mar 10, 2021 at 02:57:57PM +0200, Max Gurtovoy wrote:
>
> > > > +    .err_handler        = &vfio_pci_core_err_handlers,
> > > > +};
> > > > +
> > > > +#ifdef CONFIG_VFIO_PCI_DRIVER_COMPAT
> > > > +struct pci_driver *get_nvlink2gpu_vfio_pci_driver(struct pci_dev *pdev)
> > > > +{
> > > > +    if (pci_match_id(nvlink2gpu_vfio_pci_driver.id_table, pdev))
> > > > +        return &nvlink2gpu_vfio_pci_driver;
> > >
> > >
> > > Why do we need matching PCI ids here instead of looking at the FDT which
> > > will work better?
> >
> > what is FDT ? any is it better to use it instead of match_id ?
>
> This is emulating the device_driver match for the pci_driver.


No it is not, it is a device tree info which lets to skip the linux PCI 
discovery part (the firmware does it anyway) but it tells nothing about 
which drivers to bind.


> I don't think we can combine FDT matching with pci_driver, can we?

It is a c function calling another c function, all within vfio-pci, this 
is not called by the generic pci code.



--
Alexey