[PATCH v2 2/5] powerpc/pci: Create pci_dn on demand

[Sergey Miroshnichenko]

The pci_dn structures can be created not only from DT, but also
directly from newly discovered PCIe devices, so allocate them
dynamically.

Signed-off-by: Sergey Miroshnichenko <s.miroshnichenko at yadro.com>
---
 arch/powerpc/kernel/pci_dn.c | 76 ++++++++++++++++++++++++++++--------
 1 file changed, 59 insertions(+), 17 deletions(-)

diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c
index ab147a1909c8..48ec16407835 100644
--- a/arch/powerpc/kernel/pci_dn.c
+++ b/arch/powerpc/kernel/pci_dn.c
@@ -33,6 +33,8 @@
 #include <asm/firmware.h>
 #include <asm/eeh.h>
 
+static struct pci_dn *create_pdn(struct pci_dev *pdev, struct pci_dn *parent);
+
 /*
  * The function is used to find the firmware data of one
  * specific PCI device, which is attached to the indicated
@@ -58,6 +60,9 @@ static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus)
 		pbus = pbus->parent;
 	}
 
+	if (!pbus->self && !pci_is_root_bus(pbus))
+		return NULL;
+
 	/*
 	 * Except virtual bus, all PCI buses should
 	 * have device nodes.
@@ -65,13 +70,15 @@ static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus)
 	dn = pci_bus_to_OF_node(pbus);
 	pdn = dn ? PCI_DN(dn) : NULL;
 
+	if (!pdn && pbus->self)
+		pdn = pbus->self->dev.archdata.pci_data;
+
 	return pdn;
 }
 
 struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,
 				    int devfn)
 {
-	struct device_node *dn = NULL;
 	struct pci_dn *parent, *pdn;
 	struct pci_dev *pdev = NULL;
 
@@ -80,17 +87,10 @@ struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,
 		if (pdev->devfn == devfn) {
 			if (pdev->dev.archdata.pci_data)
 				return pdev->dev.archdata.pci_data;
-
-			dn = pci_device_to_OF_node(pdev);
 			break;
 		}
 	}
 
-	/* Fast path: fetch from device node */
-	pdn = dn ? PCI_DN(dn) : NULL;
-	if (pdn)
-		return pdn;
-
 	/* Slow path: fetch from firmware data hierarchy */
 	parent = pci_bus_to_pdn(bus);
 	if (!parent)
@@ -128,16 +128,9 @@ struct pci_dn *pci_get_pdn(struct pci_dev *pdev)
 	if (!parent)
 		return NULL;
 
-	list_for_each_entry(pdn, &parent->child_list, list) {
-		if (pdn->busno == pdev->bus->number &&
-		    pdn->devfn == pdev->devfn)
-			return pdn;
-	}
-
-	return NULL;
+	return create_pdn(pdev, parent);
 }
 
-#ifdef CONFIG_PCI_IOV
 static struct pci_dn *add_one_dev_pci_data(struct pci_dn *parent,
 					   int vf_index,
 					   int busno, int devfn)
@@ -156,7 +149,9 @@ static struct pci_dn *add_one_dev_pci_data(struct pci_dn *parent,
 	pdn->parent = parent;
 	pdn->busno = busno;
 	pdn->devfn = devfn;
+	#ifdef CONFIG_PCI_IOV
 	pdn->vf_index = vf_index;
+	#endif /* CONFIG_PCI_IOV */
 	pdn->pe_number = IODA_INVALID_PE;
 	INIT_LIST_HEAD(&pdn->child_list);
 	INIT_LIST_HEAD(&pdn->list);
@@ -164,7 +159,54 @@ static struct pci_dn *add_one_dev_pci_data(struct pci_dn *parent,
 
 	return pdn;
 }
-#endif
+
+static struct pci_dn *create_pdn(struct pci_dev *pdev, struct pci_dn *parent)
+{
+	struct pci_dn *pdn = NULL;
+
+	pdn = add_one_dev_pci_data(parent, 0, pdev->bus->number, pdev->devfn);
+	dev_info(&pdev->dev, "Create a new pdn for devfn %2x\n", pdev->devfn / 8);
+
+	if (pdn) {
+		#ifdef CONFIG_EEH
+		struct eeh_dev *edev;
+		#endif /* CONFIG_EEH */
+		u32 class_code;
+		u16 device_id;
+		u16 vendor_id;
+
+		#ifdef CONFIG_EEH
+		edev = eeh_dev_init(pdn);
+		if (!edev) {
+			kfree(pdn);
+			dev_err(&pdev->dev, "%s: Failed to allocate edev\n", __func__);
+			return NULL;
+		}
+		#endif /* CONFIG_EEH */
+
+		pdn->busno = pdev->bus->busn_res.start;
+
+		pci_bus_read_config_word(pdev->bus, pdev->devfn,
+					 PCI_VENDOR_ID, &vendor_id);
+		pdn->vendor_id = vendor_id;
+
+		pci_bus_read_config_word(pdev->bus, pdev->devfn,
+					 PCI_DEVICE_ID, &device_id);
+		pdn->device_id = device_id;
+
+		pci_bus_read_config_dword(pdev->bus, pdev->devfn,
+					  PCI_CLASS_REVISION, &class_code);
+		class_code >>= 8;
+		pdn->class_code = class_code;
+
+		pdn->pci_ext_config_space = 0;
+		pdev->dev.archdata.pci_data = pdn;
+	} else {
+		dev_err(&pdev->dev, "%s: Failed to allocate pdn\n", __func__);
+	}
+
+	return pdn;
+}
 
 struct pci_dn *add_dev_pci_data(struct pci_dev *pdev)
 {
-- 
2.17.1