[PATCH] powerpc/powernv: Escalate reset when IODA reset fails

[Oliver]

On Mon, Feb 4, 2019 at 3:45 PM Alexey Kardashevskiy <aik at ozlabs.ru> wrote:
>
>
>
> On 01/02/2019 11:42, Oliver O'Halloran wrote:
> > The IODA reset is used to flush out any OS controlled state from the PHB.
> > This reset can fail if a PHB fatal error has occurred in early boot,
> > probably due to a because of a bad device. We already do a fundemental
> > reset of the device in some cases, so this patch just adds a test to force
> > a full reset if firmware reports an error when performing the IODA reset.
> >
> > Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
>
> I am pretty sure I already saw this :-/

Uh yeah, looks like I posted it a while ago and forgot I did.

>
> ah, anyway
>
> Reviewed-by: Alexey Kardashevskiy <aik at ozlabs.ru>
>
>
>
>
> > ---
> >  arch/powerpc/platforms/powernv/pci-ioda.c | 7 +++++--
> >  1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
> > index 1d6406a..53982f8 100644
> > --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> > +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> > @@ -3943,9 +3943,12 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
> >        * shutdown PCI devices correctly. We already got IODA table
> >        * cleaned out. So we have to issue PHB reset to stop all PCI
> >        * transactions from previous kernel. The ppc_pci_reset_phbs
> > -      * kernel parameter will force this reset too.
> > +      * kernel parameter will force this reset too. Additionally,
> > +      * if the IODA reset above failed then use a bigger hammer.
> > +      * This can happen if we get a PHB fatal error in very early
> > +      * boot.
> >        */
> > -     if (is_kdump_kernel() || pci_reset_phbs) {
> > +     if (is_kdump_kernel() || pci_reset_phbs || rc) {
> >               pr_info("  Issue PHB reset ...\n");
> >               pnv_eeh_phb_reset(hose, EEH_RESET_FUNDAMENTAL);
> >               pnv_eeh_phb_reset(hose, EEH_RESET_DEACTIVATE);
> >
>
> --
> Alexey