diff mbox series

[11/17] ppc/pnv: introduce PnvPHB4 'phb_number' property

Message ID 20220113192952.911188-12-danielhb413@gmail.com
State New
Headers show
Series remove PnvPhb4PecStack from Powernv9 | expand

Commit Message

Daniel Henrique Barboza Jan. 13, 2022, 7:29 p.m. UTC 
One of the remaining dependencies we have on the PnvPhb4PecStack object
is the stack->stack_no property. This is set as the position the stack
occupies in the pec->stacks[] array.

We need a way to report this same value in the PnvPHB4. This patch
creates a new property called 'phb_number' to be used in existing code
in all instances stack->stack_no is currently being used.

The 'phb_number' name is an indication of our future intention to convert
the pec->stacks[] array into a pec->phbs[] array, when the PEC object will
deal directly with phb4 objects.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
---
 hw/pci-host/pnv_phb4.c         | 28 +++++++++++++++++-----------
 hw/pci-host/pnv_phb4_pec.c     |  2 ++
 include/hw/pci-host/pnv_phb4.h |  3 +++
 3 files changed, 22 insertions(+), 11 deletions(-)

Comments

Cédric Le Goater Jan. 14, 2022, 10:46 a.m. UTC | #1 
On 1/13/22 20:29, Daniel Henrique Barboza wrote:
> One of the remaining dependencies we have on the PnvPhb4PecStack object
> is the stack->stack_no property. This is set as the position the stack
> occupies in the pec->stacks[] array.
> 
> We need a way to report this same value in the PnvPHB4. This patch
> creates a new property called 'phb_number' to be used in existing code
> in all instances stack->stack_no is currently being used.
> 
> The 'phb_number' name is an indication of our future intention to convert
> the pec->stacks[] array into a pec->phbs[] array, when the PEC object will
> deal directly with phb4 objects.


So the PHB would have a 'phb_number' and a 'index' property ? That's
confusing. Can we simplify ? compute one from another ?

or keep 'stack_no' to make it clear this belongs to the stack subunit
logic.

Thanks,

C.

> 
> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
> ---
>   hw/pci-host/pnv_phb4.c         | 28 +++++++++++++++++-----------
>   hw/pci-host/pnv_phb4_pec.c     |  2 ++
>   include/hw/pci-host/pnv_phb4.h |  3 +++
>   3 files changed, 22 insertions(+), 11 deletions(-)
> 
> diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
> index b5045fca64..44f3087913 100644
> --- a/hw/pci-host/pnv_phb4.c
> +++ b/hw/pci-host/pnv_phb4.c
> @@ -937,7 +937,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>           mask = phb->nest_regs[PEC_NEST_STK_MMIO_BAR0_MASK];
>           size = ((~mask) >> 8) + 1;
>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-mmio0",
> -                 pec->chip_id, pec->index, stack->stack_no);
> +                 pec->chip_id, pec->index, phb->phb_number);
>           memory_region_init(&phb->mmbar0, OBJECT(phb), name, size);
>           memory_region_add_subregion(sysmem, bar, &phb->mmbar0);
>           phb->mmio0_base = bar;
> @@ -949,7 +949,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>           mask = phb->nest_regs[PEC_NEST_STK_MMIO_BAR1_MASK];
>           size = ((~mask) >> 8) + 1;
>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-mmio1",
> -                 pec->chip_id, pec->index, stack->stack_no);
> +                 pec->chip_id, pec->index, phb->phb_number);
>           memory_region_init(&phb->mmbar1, OBJECT(phb), name, size);
>           memory_region_add_subregion(sysmem, bar, &phb->mmbar1);
>           phb->mmio1_base = bar;
> @@ -960,7 +960,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>           bar = phb->nest_regs[PEC_NEST_STK_PHB_REGS_BAR] >> 8;
>           size = PNV_PHB4_NUM_REGS << 3;
>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d",
> -                 pec->chip_id, pec->index, stack->stack_no);
> +                 pec->chip_id, pec->index, phb->phb_number);
>           memory_region_init(&phb->phbbar, OBJECT(phb), name, size);
>           memory_region_add_subregion(sysmem, bar, &phb->phbbar);
>       }
> @@ -969,7 +969,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>           bar = phb->nest_regs[PEC_NEST_STK_INT_BAR] >> 8;
>           size = PNV_PHB4_MAX_INTs << 16;
>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-int",
> -                 stack->pec->chip_id, stack->pec->index, stack->stack_no);
> +                 stack->pec->chip_id, stack->pec->index, phb->phb_number);
>           memory_region_init(&phb->intbar, OBJECT(phb), name, size);
>           memory_region_add_subregion(sysmem, bar, &phb->intbar);
>       }
> @@ -1469,20 +1469,20 @@ static void pnv_phb4_xscom_realize(PnvPHB4 *phb)
>   
>       /* Initialize the XSCOM regions for the stack registers */
>       snprintf(name, sizeof(name), "xscom-pec-%d.%d-nest-phb-%d",
> -             pec->chip_id, pec->index, stack->stack_no);
> +             pec->chip_id, pec->index, phb->phb_number);
>       pnv_xscom_region_init(&phb->nest_regs_mr, OBJECT(phb),
>                             &pnv_pec_stk_nest_xscom_ops, phb, name,
>                             PHB4_PEC_NEST_STK_REGS_COUNT);
>   
>       snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-phb-%d",
> -             pec->chip_id, pec->index, stack->stack_no);
> +             pec->chip_id, pec->index, phb->phb_number);
>       pnv_xscom_region_init(&phb->pci_regs_mr, OBJECT(phb),
>                             &pnv_pec_stk_pci_xscom_ops, phb, name,
>                             PHB4_PEC_PCI_STK_REGS_COUNT);
>   
>       /* PHB pass-through */
>       snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-phb-%d",
> -             pec->chip_id, pec->index, stack->stack_no);
> +             pec->chip_id, pec->index, phb->phb_number);
>       pnv_xscom_region_init(&phb->phb_regs_mr, OBJECT(phb),
>                             &pnv_phb4_xscom_ops, phb, name, 0x40);
>   
> @@ -1491,14 +1491,14 @@ static void pnv_phb4_xscom_realize(PnvPHB4 *phb)
>   
>       /* Populate the XSCOM address space. */
>       pnv_xscom_add_subregion(pec->chip,
> -                            pec_nest_base + 0x40 * (stack->stack_no + 1),
> +                            pec_nest_base + 0x40 * (phb->phb_number + 1),
>                               &phb->nest_regs_mr);
>       pnv_xscom_add_subregion(pec->chip,
> -                            pec_pci_base + 0x40 * (stack->stack_no + 1),
> +                            pec_pci_base + 0x40 * (phb->phb_number + 1),
>                               &phb->pci_regs_mr);
>       pnv_xscom_add_subregion(pec->chip,
>                               pec_pci_base + PNV9_XSCOM_PEC_PCI_STK0 +
> -                            0x40 * stack->stack_no,
> +                            0x40 * phb->phb_number,
>                               &phb->phb_regs_mr);
>   }
>   
> @@ -1568,10 +1568,15 @@ static void pnv_phb4_realize(DeviceState *dev, Error **errp)
>               return;
>           }
>   
> -        /* All other phb properties but 'version' are already set */
> +        /*
> +         * All other phb properties but 'version' and 'phb-number'
> +         * are already set.
> +         */
>           pecc = PNV_PHB4_PEC_GET_CLASS(phb->stack->pec);
>           object_property_set_int(OBJECT(phb), "version", pecc->version,
>                                   &error_fatal);
> +        object_property_set_int(OBJECT(phb), "phb-number",
> +                                phb->stack->stack_no, &error_abort);
>   
>           /*
>            * Assign stack->phb since pnv_phb4_update_regions() uses it
> @@ -1677,6 +1682,7 @@ static void pnv_phb4_xive_notify(XiveNotifier *xf, uint32_t srcno)
>   }
>   
>   static Property pnv_phb4_properties[] = {
> +        DEFINE_PROP_UINT32("phb-number", PnvPHB4, phb_number, 0),
>           DEFINE_PROP_UINT32("index", PnvPHB4, phb_id, 0),
>           DEFINE_PROP_UINT32("chip-id", PnvPHB4, chip_id, 0),
>           DEFINE_PROP_UINT64("version", PnvPHB4, version, 0),
> diff --git a/hw/pci-host/pnv_phb4_pec.c b/hw/pci-host/pnv_phb4_pec.c
> index 7fe7f1f007..7c4b4023df 100644
> --- a/hw/pci-host/pnv_phb4_pec.c
> +++ b/hw/pci-host/pnv_phb4_pec.c
> @@ -285,6 +285,8 @@ static void pnv_pec_stk_default_phb_realize(PnvPhb4PecStack *stack,
>   
>       stack->phb = PNV_PHB4(qdev_new(TYPE_PNV_PHB4));
>   
> +    object_property_set_int(OBJECT(stack->phb), "phb-number", stack->stack_no,
> +                            &error_abort);
>       object_property_set_int(OBJECT(stack->phb), "chip-id", pec->chip_id,
>                               &error_fatal);
>       object_property_set_int(OBJECT(stack->phb), "index", phb_id,
> diff --git a/include/hw/pci-host/pnv_phb4.h b/include/hw/pci-host/pnv_phb4.h
> index 6968efaba8..fc7807be1c 100644
> --- a/include/hw/pci-host/pnv_phb4.h
> +++ b/include/hw/pci-host/pnv_phb4.h
> @@ -84,6 +84,9 @@ struct PnvPHB4 {
>   
>       uint64_t version;
>   
> +    /* My own PHB number */
> +    uint32_t phb_number;
> +
>       char bus_path[8];
>   
>       /* Main register images */
>
Daniel Henrique Barboza Jan. 14, 2022, 11:29 a.m. UTC | #2 
On 1/14/22 07:46, Cédric Le Goater wrote:
> On 1/13/22 20:29, Daniel Henrique Barboza wrote:
>> One of the remaining dependencies we have on the PnvPhb4PecStack object
>> is the stack->stack_no property. This is set as the position the stack
>> occupies in the pec->stacks[] array.
>>
>> We need a way to report this same value in the PnvPHB4. This patch
>> creates a new property called 'phb_number' to be used in existing code
>> in all instances stack->stack_no is currently being used.
>>
>> The 'phb_number' name is an indication of our future intention to convert
>> the pec->stacks[] array into a pec->phbs[] array, when the PEC object will
>> deal directly with phb4 objects.
> 
> 
> So the PHB would have a 'phb_number' and a 'index' property ? That's
> confusing. Can we simplify ? compute one from another ?
> 
> or keep 'stack_no' to make it clear this belongs to the stack subunit
> logic.


I guess for now we can keep it as phb->stack_no. We can think about reworking the
logic (my initial reaction is to keep 'index' and then derive the 'stack_no' from
it when needed) in a follow up.



Thanks,


Daniel

> 
> Thanks,
> 
> C.
> 
>>
>> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
>> ---
>>   hw/pci-host/pnv_phb4.c         | 28 +++++++++++++++++-----------
>>   hw/pci-host/pnv_phb4_pec.c     |  2 ++
>>   include/hw/pci-host/pnv_phb4.h |  3 +++
>>   3 files changed, 22 insertions(+), 11 deletions(-)
>>
>> diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
>> index b5045fca64..44f3087913 100644
>> --- a/hw/pci-host/pnv_phb4.c
>> +++ b/hw/pci-host/pnv_phb4.c
>> @@ -937,7 +937,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>>           mask = phb->nest_regs[PEC_NEST_STK_MMIO_BAR0_MASK];
>>           size = ((~mask) >> 8) + 1;
>>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-mmio0",
>> -                 pec->chip_id, pec->index, stack->stack_no);
>> +                 pec->chip_id, pec->index, phb->phb_number);
>>           memory_region_init(&phb->mmbar0, OBJECT(phb), name, size);
>>           memory_region_add_subregion(sysmem, bar, &phb->mmbar0);
>>           phb->mmio0_base = bar;
>> @@ -949,7 +949,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>>           mask = phb->nest_regs[PEC_NEST_STK_MMIO_BAR1_MASK];
>>           size = ((~mask) >> 8) + 1;
>>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-mmio1",
>> -                 pec->chip_id, pec->index, stack->stack_no);
>> +                 pec->chip_id, pec->index, phb->phb_number);
>>           memory_region_init(&phb->mmbar1, OBJECT(phb), name, size);
>>           memory_region_add_subregion(sysmem, bar, &phb->mmbar1);
>>           phb->mmio1_base = bar;
>> @@ -960,7 +960,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>>           bar = phb->nest_regs[PEC_NEST_STK_PHB_REGS_BAR] >> 8;
>>           size = PNV_PHB4_NUM_REGS << 3;
>>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d",
>> -                 pec->chip_id, pec->index, stack->stack_no);
>> +                 pec->chip_id, pec->index, phb->phb_number);
>>           memory_region_init(&phb->phbbar, OBJECT(phb), name, size);
>>           memory_region_add_subregion(sysmem, bar, &phb->phbbar);
>>       }
>> @@ -969,7 +969,7 @@ static void pnv_pec_stk_update_map(PnvPHB4 *phb)
>>           bar = phb->nest_regs[PEC_NEST_STK_INT_BAR] >> 8;
>>           size = PNV_PHB4_MAX_INTs << 16;
>>           snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-int",
>> -                 stack->pec->chip_id, stack->pec->index, stack->stack_no);
>> +                 stack->pec->chip_id, stack->pec->index, phb->phb_number);
>>           memory_region_init(&phb->intbar, OBJECT(phb), name, size);
>>           memory_region_add_subregion(sysmem, bar, &phb->intbar);
>>       }
>> @@ -1469,20 +1469,20 @@ static void pnv_phb4_xscom_realize(PnvPHB4 *phb)
>>       /* Initialize the XSCOM regions for the stack registers */
>>       snprintf(name, sizeof(name), "xscom-pec-%d.%d-nest-phb-%d",
>> -             pec->chip_id, pec->index, stack->stack_no);
>> +             pec->chip_id, pec->index, phb->phb_number);
>>       pnv_xscom_region_init(&phb->nest_regs_mr, OBJECT(phb),
>>                             &pnv_pec_stk_nest_xscom_ops, phb, name,
>>                             PHB4_PEC_NEST_STK_REGS_COUNT);
>>       snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-phb-%d",
>> -             pec->chip_id, pec->index, stack->stack_no);
>> +             pec->chip_id, pec->index, phb->phb_number);
>>       pnv_xscom_region_init(&phb->pci_regs_mr, OBJECT(phb),
>>                             &pnv_pec_stk_pci_xscom_ops, phb, name,
>>                             PHB4_PEC_PCI_STK_REGS_COUNT);
>>       /* PHB pass-through */
>>       snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-phb-%d",
>> -             pec->chip_id, pec->index, stack->stack_no);
>> +             pec->chip_id, pec->index, phb->phb_number);
>>       pnv_xscom_region_init(&phb->phb_regs_mr, OBJECT(phb),
>>                             &pnv_phb4_xscom_ops, phb, name, 0x40);
>> @@ -1491,14 +1491,14 @@ static void pnv_phb4_xscom_realize(PnvPHB4 *phb)
>>       /* Populate the XSCOM address space. */
>>       pnv_xscom_add_subregion(pec->chip,
>> -                            pec_nest_base + 0x40 * (stack->stack_no + 1),
>> +                            pec_nest_base + 0x40 * (phb->phb_number + 1),
>>                               &phb->nest_regs_mr);
>>       pnv_xscom_add_subregion(pec->chip,
>> -                            pec_pci_base + 0x40 * (stack->stack_no + 1),
>> +                            pec_pci_base + 0x40 * (phb->phb_number + 1),
>>                               &phb->pci_regs_mr);
>>       pnv_xscom_add_subregion(pec->chip,
>>                               pec_pci_base + PNV9_XSCOM_PEC_PCI_STK0 +
>> -                            0x40 * stack->stack_no,
>> +                            0x40 * phb->phb_number,
>>                               &phb->phb_regs_mr);
>>   }
>> @@ -1568,10 +1568,15 @@ static void pnv_phb4_realize(DeviceState *dev, Error **errp)
>>               return;
>>           }
>> -        /* All other phb properties but 'version' are already set */
>> +        /*
>> +         * All other phb properties but 'version' and 'phb-number'
>> +         * are already set.
>> +         */
>>           pecc = PNV_PHB4_PEC_GET_CLASS(phb->stack->pec);
>>           object_property_set_int(OBJECT(phb), "version", pecc->version,
>>                                   &error_fatal);
>> +        object_property_set_int(OBJECT(phb), "phb-number",
>> +                                phb->stack->stack_no, &error_abort);
>>           /*
>>            * Assign stack->phb since pnv_phb4_update_regions() uses it
>> @@ -1677,6 +1682,7 @@ static void pnv_phb4_xive_notify(XiveNotifier *xf, uint32_t srcno)
>>   }
>>   static Property pnv_phb4_properties[] = {
>> +        DEFINE_PROP_UINT32("phb-number", PnvPHB4, phb_number, 0),
>>           DEFINE_PROP_UINT32("index", PnvPHB4, phb_id, 0),
>>           DEFINE_PROP_UINT32("chip-id", PnvPHB4, chip_id, 0),
>>           DEFINE_PROP_UINT64("version", PnvPHB4, version, 0),
>> diff --git a/hw/pci-host/pnv_phb4_pec.c b/hw/pci-host/pnv_phb4_pec.c
>> index 7fe7f1f007..7c4b4023df 100644
>> --- a/hw/pci-host/pnv_phb4_pec.c
>> +++ b/hw/pci-host/pnv_phb4_pec.c
>> @@ -285,6 +285,8 @@ static void pnv_pec_stk_default_phb_realize(PnvPhb4PecStack *stack,
>>       stack->phb = PNV_PHB4(qdev_new(TYPE_PNV_PHB4));
>> +    object_property_set_int(OBJECT(stack->phb), "phb-number", stack->stack_no,
>> +                            &error_abort);
>>       object_property_set_int(OBJECT(stack->phb), "chip-id", pec->chip_id,
>>                               &error_fatal);
>>       object_property_set_int(OBJECT(stack->phb), "index", phb_id,
>> diff --git a/include/hw/pci-host/pnv_phb4.h b/include/hw/pci-host/pnv_phb4.h
>> index 6968efaba8..fc7807be1c 100644
>> --- a/include/hw/pci-host/pnv_phb4.h
>> +++ b/include/hw/pci-host/pnv_phb4.h
>> @@ -84,6 +84,9 @@ struct PnvPHB4 {
>>       uint64_t version;
>> +    /* My own PHB number */
>> +    uint32_t phb_number;
>> +
>>       char bus_path[8];
>>       /* Main register images */
>>
>
Cédric Le Goater Jan. 14, 2022, 11:38 a.m. UTC | #3 
On 1/14/22 12:29, Daniel Henrique Barboza wrote:
> 
> 
> On 1/14/22 07:46, Cédric Le Goater wrote:
>> On 1/13/22 20:29, Daniel Henrique Barboza wrote:
>>> One of the remaining dependencies we have on the PnvPhb4PecStack object
>>> is the stack->stack_no property. This is set as the position the stack
>>> occupies in the pec->stacks[] array.
>>>
>>> We need a way to report this same value in the PnvPHB4. This patch
>>> creates a new property called 'phb_number' to be used in existing code
>>> in all instances stack->stack_no is currently being used.
>>>
>>> The 'phb_number' name is an indication of our future intention to convert
>>> the pec->stacks[] array into a pec->phbs[] array, when the PEC object will
>>> deal directly with phb4 objects.
>>
>>
>> So the PHB would have a 'phb_number' and a 'index' property ? That's
>> confusing. Can we simplify ? compute one from another ?
>>
>> or keep 'stack_no' to make it clear this belongs to the stack subunit
>> logic.
> 
> 
> I guess for now we can keep it as phb->stack_no. We can think about reworking the
> logic (my initial reaction is to keep 'index' and then derive the 'stack_no' from
> it when needed) in a follow up.

ok. Patches 1-10 are fine. no need to resend.

Thanks,

C.
diff mbox series

Patch

diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
index b5045fca64..44f3087913 100644
--- a/hw/pci-host/pnv_phb4.c
+++ b/hw/pci-host/pnv_phb4.c
@@ -937,7 +937,7 @@  static void pnv_pec_stk_update_map(PnvPHB4 *phb)
         mask = phb->nest_regs[PEC_NEST_STK_MMIO_BAR0_MASK];
         size = ((~mask) >> 8) + 1;
         snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-mmio0",
-                 pec->chip_id, pec->index, stack->stack_no);
+                 pec->chip_id, pec->index, phb->phb_number);
         memory_region_init(&phb->mmbar0, OBJECT(phb), name, size);
         memory_region_add_subregion(sysmem, bar, &phb->mmbar0);
         phb->mmio0_base = bar;
@@ -949,7 +949,7 @@  static void pnv_pec_stk_update_map(PnvPHB4 *phb)
         mask = phb->nest_regs[PEC_NEST_STK_MMIO_BAR1_MASK];
         size = ((~mask) >> 8) + 1;
         snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-mmio1",
-                 pec->chip_id, pec->index, stack->stack_no);
+                 pec->chip_id, pec->index, phb->phb_number);
         memory_region_init(&phb->mmbar1, OBJECT(phb), name, size);
         memory_region_add_subregion(sysmem, bar, &phb->mmbar1);
         phb->mmio1_base = bar;
@@ -960,7 +960,7 @@  static void pnv_pec_stk_update_map(PnvPHB4 *phb)
         bar = phb->nest_regs[PEC_NEST_STK_PHB_REGS_BAR] >> 8;
         size = PNV_PHB4_NUM_REGS << 3;
         snprintf(name, sizeof(name), "pec-%d.%d-phb-%d",
-                 pec->chip_id, pec->index, stack->stack_no);
+                 pec->chip_id, pec->index, phb->phb_number);
         memory_region_init(&phb->phbbar, OBJECT(phb), name, size);
         memory_region_add_subregion(sysmem, bar, &phb->phbbar);
     }
@@ -969,7 +969,7 @@  static void pnv_pec_stk_update_map(PnvPHB4 *phb)
         bar = phb->nest_regs[PEC_NEST_STK_INT_BAR] >> 8;
         size = PNV_PHB4_MAX_INTs << 16;
         snprintf(name, sizeof(name), "pec-%d.%d-phb-%d-int",
-                 stack->pec->chip_id, stack->pec->index, stack->stack_no);
+                 stack->pec->chip_id, stack->pec->index, phb->phb_number);
         memory_region_init(&phb->intbar, OBJECT(phb), name, size);
         memory_region_add_subregion(sysmem, bar, &phb->intbar);
     }
@@ -1469,20 +1469,20 @@  static void pnv_phb4_xscom_realize(PnvPHB4 *phb)
 
     /* Initialize the XSCOM regions for the stack registers */
     snprintf(name, sizeof(name), "xscom-pec-%d.%d-nest-phb-%d",
-             pec->chip_id, pec->index, stack->stack_no);
+             pec->chip_id, pec->index, phb->phb_number);
     pnv_xscom_region_init(&phb->nest_regs_mr, OBJECT(phb),
                           &pnv_pec_stk_nest_xscom_ops, phb, name,
                           PHB4_PEC_NEST_STK_REGS_COUNT);
 
     snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-phb-%d",
-             pec->chip_id, pec->index, stack->stack_no);
+             pec->chip_id, pec->index, phb->phb_number);
     pnv_xscom_region_init(&phb->pci_regs_mr, OBJECT(phb),
                           &pnv_pec_stk_pci_xscom_ops, phb, name,
                           PHB4_PEC_PCI_STK_REGS_COUNT);
 
     /* PHB pass-through */
     snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-phb-%d",
-             pec->chip_id, pec->index, stack->stack_no);
+             pec->chip_id, pec->index, phb->phb_number);
     pnv_xscom_region_init(&phb->phb_regs_mr, OBJECT(phb),
                           &pnv_phb4_xscom_ops, phb, name, 0x40);
 
@@ -1491,14 +1491,14 @@  static void pnv_phb4_xscom_realize(PnvPHB4 *phb)
 
     /* Populate the XSCOM address space. */
     pnv_xscom_add_subregion(pec->chip,
-                            pec_nest_base + 0x40 * (stack->stack_no + 1),
+                            pec_nest_base + 0x40 * (phb->phb_number + 1),
                             &phb->nest_regs_mr);
     pnv_xscom_add_subregion(pec->chip,
-                            pec_pci_base + 0x40 * (stack->stack_no + 1),
+                            pec_pci_base + 0x40 * (phb->phb_number + 1),
                             &phb->pci_regs_mr);
     pnv_xscom_add_subregion(pec->chip,
                             pec_pci_base + PNV9_XSCOM_PEC_PCI_STK0 +
-                            0x40 * stack->stack_no,
+                            0x40 * phb->phb_number,
                             &phb->phb_regs_mr);
 }
 
@@ -1568,10 +1568,15 @@  static void pnv_phb4_realize(DeviceState *dev, Error **errp)
             return;
         }
 
-        /* All other phb properties but 'version' are already set */
+        /*
+         * All other phb properties but 'version' and 'phb-number'
+         * are already set.
+         */
         pecc = PNV_PHB4_PEC_GET_CLASS(phb->stack->pec);
         object_property_set_int(OBJECT(phb), "version", pecc->version,
                                 &error_fatal);
+        object_property_set_int(OBJECT(phb), "phb-number",
+                                phb->stack->stack_no, &error_abort);
 
         /*
          * Assign stack->phb since pnv_phb4_update_regions() uses it
@@ -1677,6 +1682,7 @@  static void pnv_phb4_xive_notify(XiveNotifier *xf, uint32_t srcno)
 }
 
 static Property pnv_phb4_properties[] = {
+        DEFINE_PROP_UINT32("phb-number", PnvPHB4, phb_number, 0),
         DEFINE_PROP_UINT32("index", PnvPHB4, phb_id, 0),
         DEFINE_PROP_UINT32("chip-id", PnvPHB4, chip_id, 0),
         DEFINE_PROP_UINT64("version", PnvPHB4, version, 0),
diff --git a/hw/pci-host/pnv_phb4_pec.c b/hw/pci-host/pnv_phb4_pec.c
index 7fe7f1f007..7c4b4023df 100644
--- a/hw/pci-host/pnv_phb4_pec.c
+++ b/hw/pci-host/pnv_phb4_pec.c
@@ -285,6 +285,8 @@  static void pnv_pec_stk_default_phb_realize(PnvPhb4PecStack *stack,
 
     stack->phb = PNV_PHB4(qdev_new(TYPE_PNV_PHB4));
 
+    object_property_set_int(OBJECT(stack->phb), "phb-number", stack->stack_no,
+                            &error_abort);
     object_property_set_int(OBJECT(stack->phb), "chip-id", pec->chip_id,
                             &error_fatal);
     object_property_set_int(OBJECT(stack->phb), "index", phb_id,
diff --git a/include/hw/pci-host/pnv_phb4.h b/include/hw/pci-host/pnv_phb4.h
index 6968efaba8..fc7807be1c 100644
--- a/include/hw/pci-host/pnv_phb4.h
+++ b/include/hw/pci-host/pnv_phb4.h
@@ -84,6 +84,9 @@  struct PnvPHB4 {
 
     uint64_t version;
 
+    /* My own PHB number */
+    uint32_t phb_number;
+
     char bus_path[8];
 
     /* Main register images */