Re: [PATCH V7 02/15] PCI: Disable MSI for Tegra194 root port

[Vidya Sagar]

On 5/21/2019 3:57 PM, Thierry Reding wrote:
> On Fri, May 17, 2019 at 06:08:33PM +0530, Vidya Sagar wrote:
> > Tegra194 rootports don't generate MSI interrupts for PME events and hence
> > MSI needs to be disabled for them to avoid root ports service drivers
> > registering their respective ISRs with MSI interrupt.
> >
> > Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
> > ---
> > Changes since [v6]:
> > * This is a new patch
> >
> >   drivers/pci/quirks.c | 14 ++++++++++++++
> >   1 file changed, 14 insertions(+)
> >
> > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> > index 0f16acc323c6..28f9a0380df5 100644
> > --- a/drivers/pci/quirks.c
> > +++ b/drivers/pci/quirks.c
> > @@ -2592,6 +2592,20 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA,
> >   			PCI_DEVICE_ID_NVIDIA_NVENET_15,
> >   			nvenet_msi_disable);
> >   
> > +/*
> > + * Tegra194's PCIe root ports don't generate MSI interrupts for PME events
> > + * instead legacy interrupts are generated. Hence, to avoid service drivers
> > + * registering their respective ISRs for MSIs, need to disable MSI interrupts
> > + * for root ports.
> > + */
> > +static void disable_tegra194_rp_msi(struct pci_dev *dev)
> > +{
> > +	dev->no_msi = 1;
> > +}
> > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x1ad0, disable_tegra194_rp_msi);
> > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x1ad1, disable_tegra194_rp_msi);
> > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x1ad2, disable_tegra194_rp_msi);
> > +
>
> Later functions in this file seem to use a more consistent naming
> pattern, according to which the name for this would become:
>
> 	pci_quirk_nvidia_tegra194_disable_rp_msi
>
> Might be worth considering making this consistent.
>
> This could also be moved to the DWC driver to restrict this to where it
> is needed. In either case, this seems like a good solution, so:
>
> Reviewed-by: Thierry Reding <treding@xxxxxxxxxx>
Ok. I'll move it to DWC driver along with name change for the quirk API.