ppc/pnv: add PHB4 bus init helper

Similar to what we already did for the PnvPHB3 device, let's add a
helper to init the bus when using a PnvPHB4. This helper will be used by
PnvPHb when PnvPHB4 turns into a backend.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com>
Message-Id: <20220624084921.399219-5-danielhb413@gmail.com>

2 files changed, 25 insertions, 16 deletions

diff --git a/hw/pci-host/pnv_phb.c b/hw/pci-host/pnv_phb.c
index 6fefff7d44..abcbcca445 100644
--- a/hw/pci-host/pnv_phb.c
+++ b/hw/pci-host/pnv_phb.c
@@ -69,6 +69,8 @@ static void pnv_phb_realize(DeviceState *dev, Error **errp)
 
     if (phb->version == 3) {
         pnv_phb3_bus_init(dev, PNV_PHB3(phb->backend));
+    } else {
+        pnv_phb4_bus_init(dev, PNV_PHB4(phb->backend));
     }
 
     pnv_phb_attach_root_port(pci, phb_rootport_typename,
diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
index 67ddde4a6e..a7425927fb 100644
--- a/hw/pci-host/pnv_phb4.c
+++ b/hw/pci-host/pnv_phb4.c
@@ -1528,30 +1528,16 @@ static void pnv_phb4_instance_init(Object *obj)
     object_initialize_child(obj, "source", &phb->xsrc, TYPE_XIVE_SOURCE);
 }
 
-static void pnv_phb4_realize(DeviceState *dev, Error **errp)
+void pnv_phb4_bus_init(DeviceState *dev, PnvPHB4 *phb)
 {
-    PnvPHB4 *phb = PNV_PHB4(dev);
-    PnvPhb4PecClass *pecc = PNV_PHB4_PEC_GET_CLASS(phb->pec);
     PCIHostState *pci = PCI_HOST_BRIDGE(dev);
-    XiveSource *xsrc = &phb->xsrc;
-    int nr_irqs;
     char name[32];
 
-    /* Set the "big_phb" flag */
-    phb->big_phb = phb->phb_id == 0 || phb->phb_id == 3;
-
-    /* Controller Registers */
-    snprintf(name, sizeof(name), "phb4-%d.%d-regs", phb->chip_id,
-             phb->phb_id);
-    memory_region_init_io(&phb->mr_regs, OBJECT(phb), &pnv_phb4_reg_ops, phb,
-                          name, 0x2000);
-
     /*
      * PHB4 doesn't support IO space. However, qemu gets very upset if
      * we don't have an IO region to anchor IO BARs onto so we just
      * initialize one which we never hook up to anything
      */
-
     snprintf(name, sizeof(name), "phb4-%d.%d-pci-io", phb->chip_id,
              phb->phb_id);
     memory_region_init(&phb->pci_io, OBJECT(phb), name, 0x10000);
@@ -1561,12 +1547,33 @@ static void pnv_phb4_realize(DeviceState *dev, Error **errp)
     memory_region_init(&phb->pci_mmio, OBJECT(phb), name,
                        PCI_MMIO_TOTAL_SIZE);
 
-    pci->bus = pci_register_root_bus(dev, dev->id,
+    pci->bus = pci_register_root_bus(dev, dev->id ? dev->id : NULL,
                                      pnv_phb4_set_irq, pnv_phb4_map_irq, phb,
                                      &phb->pci_mmio, &phb->pci_io,
                                      0, 4, TYPE_PNV_PHB4_ROOT_BUS);
     pci_setup_iommu(pci->bus, pnv_phb4_dma_iommu, phb);
     pci->bus->flags |= PCI_BUS_EXTENDED_CONFIG_SPACE;
+}
+
+static void pnv_phb4_realize(DeviceState *dev, Error **errp)
+{
+    PnvPHB4 *phb = PNV_PHB4(dev);
+    PnvPhb4PecClass *pecc = PNV_PHB4_PEC_GET_CLASS(phb->pec);
+    PCIHostState *pci = PCI_HOST_BRIDGE(dev);
+    XiveSource *xsrc = &phb->xsrc;
+    int nr_irqs;
+    char name[32];
+
+    /* Set the "big_phb" flag */
+    phb->big_phb = phb->phb_id == 0 || phb->phb_id == 3;
+
+    /* Controller Registers */
+    snprintf(name, sizeof(name), "phb4-%d.%d-regs", phb->chip_id,
+             phb->phb_id);
+    memory_region_init_io(&phb->mr_regs, OBJECT(phb), &pnv_phb4_reg_ops, phb,
+                          name, 0x2000);
+
+    pnv_phb4_bus_init(dev, phb);
 
     /* Add a single Root port if running with defaults */
     pnv_phb_attach_root_port(pci, pecc->rp_model,