Re: [PATCH] ppc/pnv: fix default PHB4 QOM hierarchy

[Daniel Henrique Barboza]

On 2/26/22 10:49, Cédric Le Goater wrote:
> On 2/18/22 21:28, Daniel Henrique Barboza wrote:
> > Commit 3f4c369ea63e ("ppc/pnv: make PECs create and realize PHB4s")
> > changed phb4_pec code to create the default PHB4 objects in
> > pnv_pec_default_phb_realize(). In this process the stacks[] PEC array was
> > removed and each PHB4 object is tied together with its PEC via the
> > phb->pec pointer.
> >
> > This change also broke the previous QOM hierarchy - the PHB4 objects are
> > being created and not being parented to their respective chips. This can
> > be verified by 'info pic' in a powernv9 domain with default settings.
> > pnv_chip_power9_pic_print_info() will fail to find the PHBs because
> > object_child_foreach_recursive() won't find any.
> >
> > The solution is to set the parent chip and the parent bus, in the same
> > way done for user created PHB4 devices, for all PHB4 devices.
> >
> > Fixes: 3f4c369ea63e ("ppc/pnv: make PECs create and realize PHB4s")
> > Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
>
>
> What about the pnv-phb3/4-root-port devices ? Should we attached
> them also to the QOM hierarchy ?


I guess it wouldn't hurt. I'll see what I can do.



Thanks,


Daniel

> Thanks,
>
> C.
>
> > ---
> >   hw/pci-host/pnv_phb4.c | 36 ++++++++++++++++--------------------
> >   1 file changed, 16 insertions(+), 20 deletions(-)
> >
> > diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
> > index e91249ef64..846e7d0c3e 100644
> > --- a/hw/pci-host/pnv_phb4.c
> > +++ b/hw/pci-host/pnv_phb4.c
> > @@ -1568,40 +1568,36 @@ static PnvPhb4PecState *pnv_phb4_get_pec(PnvChip *chip, 
> > PnvPHB4 *phb,
> >   static void pnv_phb4_realize(DeviceState *dev, Error **errp)
> >   {
> >       PnvPHB4 *phb = PNV_PHB4(dev);
> > +    PnvMachineState *pnv = PNV_MACHINE(qdev_get_machine());
> > +    PnvChip *chip = pnv_get_chip(pnv, phb->chip_id);
> >       PCIHostState *pci = PCI_HOST_BRIDGE(dev);
> >       XiveSource *xsrc = &phb->xsrc;
> > +    BusState *s;
> >       Error *local_err = NULL;
> >       int nr_irqs;
> >       char name[32];
> > -    /* User created PHB */
> > -    if (!phb->pec) {
> > -        PnvMachineState *pnv = PNV_MACHINE(qdev_get_machine());
> > -        PnvChip *chip = pnv_get_chip(pnv, phb->chip_id);
> > -        BusState *s;
> > -
> > -        if (!chip) {
> > -            error_setg(errp, "invalid chip id: %d", phb->chip_id);
> > -            return;
> > -        }
> > +    if (!chip) {
> > +        error_setg(errp, "invalid chip id: %d", phb->chip_id);
> > +        return;
> > +    }
> > +    /* User created PHBs need to be assigned to a PEC */
> > +    if (!phb->pec) {
> >           phb->pec = pnv_phb4_get_pec(chip, phb, &local_err);
> >           if (local_err) {
> >               error_propagate(errp, local_err);
> >               return;
> >           }
> > +    }
> > -        /*
> > -         * Reparent user created devices to the chip to build
> > -         * correctly the device tree.
> > -         */
> > -        pnv_chip_parent_fixup(chip, OBJECT(phb), phb->phb_id);
> > +    /* Reparent the PHB to the chip to build the device tree */
> > +    pnv_chip_parent_fixup(chip, OBJECT(phb), phb->phb_id);
> > -        s = qdev_get_parent_bus(DEVICE(chip));
> > -        if (!qdev_set_parent_bus(DEVICE(phb), s, &local_err)) {
> > -            error_propagate(errp, local_err);
> > -            return;
> > -        }
> > +    s = qdev_get_parent_bus(DEVICE(chip));
> > +    if (!qdev_set_parent_bus(DEVICE(phb), s, &local_err)) {
> > +        error_propagate(errp, local_err);
> > +        return;
> >       }
> >       /* Set the "big_phb" flag */