Re: [PATCH 2/2] uio: Prefer MSI(X) interrupts in PCI drivers

From: Stahl, Manuel
Date: Wed Mar 04 2020 - 10:26:07 EST


Hi Greg,

so somehow this discussion stopped without any instructions how to proceed.
I think this kind of driver helps every FPGA developer to interface his design via PCIe to a Linux PC.
So if there is any chance to get this code merged, I'm glad to rebase this onto the latest kernel release.

Best regards,
Manuel Stahl

On Fr, 2017-10-20 at 14:58 +0200, Manuel Stahl wrote:
> Hi Greg,
>
> it just uses MSI-X or MSI when available and falls back to legacy IRQ otherwise.
>
> Regards,
> Manuel
>
> On Fr, 2017-10-20 at 14:50 +0200, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
> > On Fri, Oct 06, 2017 at 07:57:00AM -0700, Stephen Hemminger wrote:
> > > On Fri, 6 Oct 2017 13:50:44 +0000
> > > "Stahl, Manuel" <manuel.stahl@xxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > > MSI(X) interrupts are not shared between devices. So when available
> > > > those should be preferred over legacy interrupts.
> > > >
> > > > Signed-off-by: Manuel Stahl <manuel.stahl@xxxxxxxxxxxxxxxxx>
> > > > ---
> > > > drivers/uio/uio_pci_dmem_genirq.c | 27 ++++++++++++++++++++-------
> > > > drivers/uio/uio_pci_generic.c | 24 ++++++++++++++++++------
> > > > 2 files changed, 38 insertions(+), 13 deletions(-)
> > >
> > > The last time I tried to do MSI-X with pci-generic it got rejected
> > > by the maintainer.
> >
> > Hm, yeah, this would break users today that do not have msi-x, right?
> >
> > Not good, Manuel, how well did you test this?
> >
> > thanks,
> >
> > greg k-h