pci/of: Match PCI devices to OF nodes dynamically

powerpc has two different ways of matching PCI devices to their
corresponding OF node (if any) for historical reasons. The ppc64 one
does a scan looking for matching bus/dev/fn, while the ppc32 one does a
scan looking only for matching dev/fn on each level in order to be
agnostic to busses being renumbered (which Linux does on some
platforms).

This removes both and instead moves the matching code to the PCI core
itself. It's the most logical place to do it: when a pci_dev is created,
we know the parent and thus can do a single level scan for the matching
device_node (if any).

The benefit is that all archs now get the matching for free. There's one
hook the arch might want to provide to match a PHB bus to its device
node. A default weak implementation is provided that looks for the
parent device device node, but it's not entirely reliable on powerpc for
various reasons so powerpc provides its own.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Michal Simek <monstr@monstr.eu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>

3 files changed, 12 insertions, 40 deletions

diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
index b90dbf8..3e68694 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -169,18 +169,22 @@ static inline struct pci_controller *pci_bus_to_host(const struct pci_bus *bus)
 	return bus->sysdata;
 }
 
-#ifndef CONFIG_PPC64
+static inline struct device_node *pci_device_to_OF_node(struct pci_dev *dev)
+{
+	return dev->dev.of_node;
+}
 
 static inline struct device_node *pci_bus_to_OF_node(struct pci_bus *bus)
 {
-	struct pci_controller *host;
-
-	if (bus->self)
-		return pci_device_to_OF_node(bus->self);
-	host = pci_bus_to_host(bus);
-	return host ? host->dn : NULL;
+	return bus->dev.of_node;
 }
 
+#ifndef CONFIG_PPC64
+
+extern int pci_device_from_OF_node(struct device_node *node,
+				   u8 *bus, u8 *devfn);
+extern void pci_create_OF_bus_map(void);
+
 static inline int isa_vaddr_is_ioport(void __iomem *address)
 {
 	/* No specific ISA handling on ppc32 at this stage, it
@@ -223,17 +227,8 @@ struct pci_dn {
 /* Get the pointer to a device_node's pci_dn */
 #define PCI_DN(dn)	((struct pci_dn *) (dn)->data)
 
-extern struct device_node *fetch_dev_dn(struct pci_dev *dev);
 extern void * update_dn_pci_info(struct device_node *dn, void *data);
 
-/* Get a device_node from a pci_dev.  This code must be fast except
- * in the case where the sysdata is incorrect and needs to be fixed
- * up (this will only happen once). */
-static inline struct device_node *pci_device_to_OF_node(struct pci_dev *dev)
-{
-	return dev->dev.of_node ? dev->dev.of_node : fetch_dev_dn(dev);
-}
-
 static inline int pci_device_from_OF_node(struct device_node *np,
 					  u8 *bus, u8 *devfn)
 {
@@ -244,14 +239,6 @@ static inline int pci_device_from_OF_node(struct device_node *np,
 	return 0;
 }
 
-static inline struct device_node *pci_bus_to_OF_node(struct pci_bus *bus)
-{
-	if (bus->self)
-		return pci_device_to_OF_node(bus->self);
-	else
-		return bus->dev.of_node; /* Must be root bus (PHB) */
-}
-
 /** Find the bus corresponding to the indicated device node */
 extern struct pci_bus *pcibios_find_pci_bus(struct device_node *dn);
 
diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h
index 7d77909..1f52268 100644
--- a/arch/powerpc/include/asm/pci.h
+++ b/arch/powerpc/include/asm/pci.h
@@ -179,8 +179,7 @@ extern int remove_phb_dynamic(struct pci_controller *phb);
 extern struct pci_dev *of_create_pci_dev(struct device_node *node,
 					struct pci_bus *bus, int devfn);
 
-extern void of_scan_pci_bridge(struct device_node *node,
-				struct pci_dev *dev);
+extern void of_scan_pci_bridge(struct pci_dev *dev);
 
 extern void of_scan_bus(struct device_node *node, struct pci_bus *bus);
 extern void of_rescan_bus(struct device_node *node, struct pci_bus *bus);
diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h
index c189aa5..b823536 100644
--- a/arch/powerpc/include/asm/prom.h
+++ b/arch/powerpc/include/asm/prom.h
@@ -22,20 +22,6 @@
 
 #define HAVE_ARCH_DEVTREE_FIXUPS
 
-#ifdef CONFIG_PPC32
-/*
- * PCI <-> OF matching functions
- * (XXX should these be here?)
- */
-struct pci_bus;
-struct pci_dev;
-extern int pci_device_from_OF_node(struct device_node *node,
-				   u8* bus, u8* devfn);
-extern struct device_node* pci_busdev_to_OF_node(struct pci_bus *, int);
-extern struct device_node* pci_device_to_OF_node(struct pci_dev *);
-extern void pci_create_OF_bus_map(void);
-#endif
-
 /*
  * OF address retreival & translation
  */