powerpc/powernv/ioda: set up PE on opencapi device when enabling

The PE for an opencapi device was set as part of a late PHB fixup
operation, when creating the PHB. To use the PCI hotplug framework,
this is not going to work, as the PHB stays the same, it's only the
devices underneath which are updated. For regular PCI devices, it is
done as part of the reconfiguration of the bridge, but for opencapi
PHBs, we don't have an intermediate bridge. So let's define the PE
when the device is enabled. PEs are meaningless for opencapi, the NPU
doesn't define them and opal is not doing anything with them.
Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-4-fbarrat@linux.ibm.com

arch/powerpc/platforms/powernv/pci-ioda.c

@@ -1274,8 +1274,6 @@ static void pnv_pci_ioda_setup_PEs(void)
 {
 	struct pci_controller *hose;
 	struct pnv_phb *phb;
-	struct pci_bus *bus;
-	struct pci_dev *pdev;
 	struct pnv_ioda_pe *pe;
 
 	list_for_each_entry(hose, &hose_list, list_node) {
@@ -1287,11 +1285,6 @@ static void pnv_pci_ioda_setup_PEs(void)
 			if (phb->model == PNV_PHB_MODEL_NPU2)
 				WARN_ON_ONCE(pnv_npu2_init(hose));
 		}
-		if (phb->type == PNV_PHB_NPU_OCAPI) {
-			bus = hose->bus;
-			list_for_each_entry(pdev, &bus->devices, bus_list)
-				pnv_ioda_setup_dev_PE(pdev);
-		}
 	}
 	list_for_each_entry(hose, &hose_list, list_node) {
 		phb = hose->private_data;
@@ -3400,6 +3393,28 @@ static bool pnv_pci_enable_device_hook(struct pci_dev *dev)
 	return true;
 }
 
+static bool pnv_ocapi_enable_device_hook(struct pci_dev *dev)
+{
+	struct pci_controller *hose = pci_bus_to_host(dev->bus);
+	struct pnv_phb *phb = hose->private_data;
+	struct pci_dn *pdn;
+	struct pnv_ioda_pe *pe;
+
+	if (!phb->initialized)
+		return true;
+
+	pdn = pci_get_pdn(dev);
+	if (!pdn)
+		return false;
+
+	if (pdn->pe_number == IODA_INVALID_PE) {
+		pe = pnv_ioda_setup_dev_PE(dev);
+		if (!pe)
+			return false;
+	}
+	return true;
+}
+
 static long pnv_pci_ioda1_unset_window(struct iommu_table_group *table_group,
 				       int num)
 {
@@ -3640,7 +3655,7 @@ static const struct pci_controller_ops pnv_npu_ioda_controller_ops = {
 };
 
 static const struct pci_controller_ops pnv_npu_ocapi_ioda_controller_ops = {
-	.enable_device_hook	= pnv_pci_enable_device_hook,
+	.enable_device_hook	= pnv_ocapi_enable_device_hook,
 	.window_alignment	= pnv_pci_window_alignment,
 	.reset_secondary_bus	= pnv_pci_reset_secondary_bus,
 	.shutdown		= pnv_pci_ioda_shutdown,