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

[Daniel Henrique Barboza <danielhb413@gmail.com>]

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 */
>