On Wed, 2020-08-26 at 21:42 +0100, Marc Zyngier wrote:
> On Wed, 26 Aug 2020 12:16:51 +0100,
> Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> > From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> >
> > PCI devices behind a VMD bus are not subject to interrupt remapping, but
> > the irq domain for VMD MSI cannot be distinguished from a regular PCI/MSI
> > irq domain.
> >
> > Add a new domain bus token and allow it in the bus token check in
> > msi_check_reservation_mode() to keep the functionality the same once VMD
> > uses this token.
> >
> > Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> >
> > ---
> > include/linux/irqdomain.h | 1 +
> > kernel/irq/msi.c | 7 ++++++-
> > 2 files changed, 7 insertions(+), 1 deletion(-)
> >
> > --- a/include/linux/irqdomain.h
> > +++ b/include/linux/irqdomain.h
> > @@ -84,6 +84,7 @@ enum irq_domain_bus_token {
> > DOMAIN_BUS_FSL_MC_MSI,
> > DOMAIN_BUS_TI_SCI_INTA_MSI,
> > DOMAIN_BUS_WAKEUP,
> > + DOMAIN_BUS_VMD_MSI,
> > };
> >
> > /**
> > --- a/kernel/irq/msi.c
> > +++ b/kernel/irq/msi.c
> > @@ -370,8 +370,13 @@ static bool msi_check_reservation_mode(s
> > {
> > struct msi_desc *desc;
> >
> > - if (domain->bus_token != DOMAIN_BUS_PCI_MSI)
> > + switch(domain->bus_token) {
> > + case DOMAIN_BUS_PCI_MSI:
> > + case DOMAIN_BUS_VMD_MSI:
> > + break;
> > + default:
> > return false;
> > + }
> >
> > if (!(info->flags & MSI_FLAG_MUST_REACTIVATE))
> > return false;
>
> Acked-by: Marc Zyngier <maz@xxxxxxxxxx>
>
> M.
>
Acked-by: Jon Derrick <jonathan.derrick@xxxxxxxxx>
