powerpc/pci: Refactor pci_dn

Currently, the PCI config accessors are implemented based on device node.
Unfortunately, SRIOV VFs won't have the corresponding device nodes. pci_dn
will be used in replacement with device node for SRIOV VFs. So we have to
use pci_dn in PCI config accessors.

The patch refactors pci_dn in following aspects to make it ready to be used
in PCI config accessors as we do in subsequent patch:

   * pci_dn is organized as a hierarchy tree.  PCI device's pci_dn is
     put to the child list of pci_dn of its upstream bridge or PHB. VF's
     pci_dn will be put to the child list of pci_dn of PF's bridge.

   * For one particular PCI device (VF or not), its pci_dn can be
     found from pdev->dev.archdata.pci_data, PCI_DN(devnode), or
     parent's list.  The fast path (fetching pci_dn through PCI device
     instance) is populated during early fixup time.

[bhelgaas: changelog]
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

2 files changed, 15 insertions, 2 deletions

diff --git a/arch/powerpc/include/asm/device.h b/arch/powerpc/include/asm/device.h
index 38faeded7d59..9f1371bab5fc 100644
--- a/arch/powerpc/include/asm/device.h
+++ b/arch/powerpc/include/asm/device.h
@@ -8,6 +8,9 @@
 
 struct dma_map_ops;
 struct device_node;
+#ifdef CONFIG_PPC64
+struct pci_dn;
+#endif
 
 /*
  * Arch extensions to struct device.
@@ -34,6 +37,9 @@ struct dev_archdata {
 #ifdef CONFIG_SWIOTLB
         dma_addr_t              max_direct_dma_addr;
 #endif
+#ifdef CONFIG_PPC64
+        struct pci_dn           *pci_data;
+#endif
 #ifdef CONFIG_EEH
         struct eeh_dev          *edev;
 #endif
diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
index 546d036fe925..706710b571c3 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -89,6 +89,7 @@ struct pci_controller {
 
 #ifdef CONFIG_PPC64
         unsigned long buid;
+        struct pci_dn *pci_data;
 #endif  /* CONFIG_PPC64 */
 
         void *private_data;
@@ -154,9 +155,12 @@ static inline int isa_vaddr_is_ioport(void __iomem *address)
 struct iommu_table;
 
 struct pci_dn {
+        int     flags;
+
         int     busno;                  /* pci bus number */
         int     devfn;                  /* pci device and function number */
 
+        struct  pci_dn *parent;
         struct  pci_controller *phb;    /* for pci devices */
         struct  iommu_table *iommu_table;       /* for phb's or bridges */
         struct  device_node *node;      /* back-pointer to the device_node */
@@ -171,14 +175,17 @@ struct pci_dn {
 #ifdef CONFIG_PPC_POWERNV
         int     pe_number;
 #endif
+        struct list_head child_list;
+        struct list_head list;
 };
 
 /* Get the pointer to a device_node's pci_dn */
 #define PCI_DN(dn)      ((struct pci_dn *) (dn)->data)
 
+extern struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,
+                                           int devfn);
 extern struct pci_dn *pci_get_pdn(struct pci_dev *pdev);
-
-extern void * update_dn_pci_info(struct device_node *dn, void *data);
+extern void *update_dn_pci_info(struct device_node *dn, void *data);
 
 static inline int pci_device_from_OF_node(struct device_node *np,
                                           u8 *bus, u8 *devfn)