arch/powerpc/kernel/pci_dn.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * pci_dn.c
  *
  * Copyright (C) 2001 Todd Inglett, IBM Corporation
  *
  * PCI manipulation via device_nodes.
  */
 #include <linux/kernel.h>
 #include <linux/pci.h>
 #include <linux/string.h>
 #include <linux/export.h>
 #include <linux/init.h>
 #include <linux/gfp.h>

 #include <asm/io.h>
 #include <asm/prom.h>
 #include <asm/pci-bridge.h>
 #include <asm/ppc-pci.h>
 #include <asm/firmware.h>
 #include <asm/eeh.h>

 /*
  * The function is used to find the firmware data of one
  * specific PCI device, which is attached to the indicated
  * PCI bus. For VFs, their firmware data is linked to that
  * one of PF's bridge. For other devices, their firmware
  * data is linked to that of their bridge.
  */
 static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus)
 {
 	struct pci_bus *pbus;
 	struct device_node *dn;
 	struct pci_dn *pdn;

 	/*
 	 * We probably have virtual bus which doesn't
 	 * have associated bridge.
 	 */
 	pbus = bus;
 	while (pbus) {
 		if (pci_is_root_bus(pbus) || pbus->self)
 			break;

 		pbus = pbus->parent;
 	}

 	/*
 	 * Except virtual bus, all PCI buses should
 	 * have device nodes.
 	 */
 	dn = pci_bus_to_OF_node(pbus);
 	pdn = dn ? PCI_DN(dn) : NULL;

 	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;

 	/* Fast path: fetch from PCI device */
 	list_for_each_entry(pdev, &bus->devices, bus_list) {
 		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)
 		return NULL;

 	list_for_each_entry(pdn, &parent->child_list, list) {
 		if (pdn->busno == bus->number &&
                     pdn->devfn == devfn)
                         return pdn;
         }

 	return NULL;
 }

 struct pci_dn *pci_get_pdn(struct pci_dev *pdev)
 {
 	struct device_node *dn;
 	struct pci_dn *parent, *pdn;

 	/* Search device directly */
 	if (pdev->dev.archdata.pci_data)
 		return pdev->dev.archdata.pci_data;

 	/* Check device node */
 	dn = pci_device_to_OF_node(pdev);
 	pdn = dn ? PCI_DN(dn) : NULL;
 	if (pdn)
 		return pdn;

 	/*
 	 * VFs don't have device nodes. We hook their
 	 * firmware data to PF's bridge.
 	 */
 	parent = pci_bus_to_pdn(pdev->bus);
 	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;
 }

 #ifdef CONFIG_PCI_IOV
 static struct pci_dn *add_one_sriov_vf_pdn(struct pci_dn *parent,
 					   int vf_index,
 					   int busno, int devfn)
 {
 	struct pci_dn *pdn;

 	/* Except PHB, we always have the parent */
 	if (!parent)
 		return NULL;

 	pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
 	if (!pdn)
 		return NULL;

 	pdn->phb = parent->phb;
 	pdn->parent = parent;
 	pdn->busno = busno;
 	pdn->devfn = devfn;
 	pdn->vf_index = vf_index;
 	pdn->pe_number = IODA_INVALID_PE;
 	INIT_LIST_HEAD(&pdn->child_list);
 	INIT_LIST_HEAD(&pdn->list);
 	list_add_tail(&pdn->list, &parent->child_list);

 	return pdn;
 }

 struct pci_dn *add_sriov_vf_pdns(struct pci_dev *pdev)
 {
 	struct pci_dn *parent, *pdn;
 	int i;

 	/* Only support IOV for now */
 	if (WARN_ON(!pdev->is_physfn))
 		return NULL;

 	/* Check if VFs have been populated */
 	pdn = pci_get_pdn(pdev);
 	if (!pdn || (pdn->flags & PCI_DN_FLAG_IOV_VF))
 		return NULL;

 	pdn->flags |= PCI_DN_FLAG_IOV_VF;
 	parent = pci_bus_to_pdn(pdev->bus);
 	if (!parent)
 		return NULL;

 	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
 		struct eeh_dev *edev __maybe_unused;

 		pdn = add_one_sriov_vf_pdn(parent, i,
 					   pci_iov_virtfn_bus(pdev, i),
 					   pci_iov_virtfn_devfn(pdev, i));
 		if (!pdn) {
 			dev_warn(&pdev->dev, "%s: Cannot create firmware data for VF#%d\n",
 				 __func__, i);
 			return NULL;
 		}

 #ifdef CONFIG_EEH
 		/* Create the EEH device for the VF */
 		edev = eeh_dev_init(pdn);
 		BUG_ON(!edev);
 		edev->physfn = pdev;
 #endif /* CONFIG_EEH */
 	}
 	return pci_get_pdn(pdev);
 }

 void remove_sriov_vf_pdns(struct pci_dev *pdev)
 {
 	struct pci_dn *parent;
 	struct pci_dn *pdn, *tmp;
 	int i;

 	/* Only support IOV PF for now */
 	if (WARN_ON(!pdev->is_physfn))
 		return;

 	/* Check if VFs have been populated */
 	pdn = pci_get_pdn(pdev);
 	if (!pdn || !(pdn->flags & PCI_DN_FLAG_IOV_VF))
 		return;

 	pdn->flags &= ~PCI_DN_FLAG_IOV_VF;
 	parent = pci_bus_to_pdn(pdev->bus);
 	if (!parent)
 		return;

 	/*
 	 * We might introduce flag to pci_dn in future
 	 * so that we can release VF's firmware data in
 	 * a batch mode.
 	 */
 	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
 		struct eeh_dev *edev __maybe_unused;

 		list_for_each_entry_safe(pdn, tmp,
 			&parent->child_list, list) {
 			if (pdn->busno != pci_iov_virtfn_bus(pdev, i) ||
 			    pdn->devfn != pci_iov_virtfn_devfn(pdev, i))
 				continue;

 #ifdef CONFIG_EEH
 			/*
 			 * Release EEH state for this VF. The PCI core
 			 * has already torn down the pci_dev for this VF, but
 			 * we're responsible to removing the eeh_dev since it
 			 * has the same lifetime as the pci_dn that spawned it.
 			 */
 			edev = pdn_to_eeh_dev(pdn);
 			if (edev) {
 				/*
 				 * We allocate pci_dn's for the totalvfs count,
 				 * but only only the vfs that were activated
 				 * have a configured PE.
 				 */
 				if (edev->pe)
 					eeh_rmv_from_parent_pe(edev);

 				pdn->edev = NULL;
 				kfree(edev);
 			}
 #endif /* CONFIG_EEH */

 			if (!list_empty(&pdn->list))
 				list_del(&pdn->list);

 			kfree(pdn);
 		}
 	}
 }
 #endif /* CONFIG_PCI_IOV */

 struct pci_dn *pci_add_device_node_info(struct pci_controller *hose,
 					struct device_node *dn)
 {
 	const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL);
 	const __be32 *regs;
 	struct device_node *parent;
 	struct pci_dn *pdn;
 #ifdef CONFIG_EEH
 	struct eeh_dev *edev;
 #endif

 	pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
 	if (pdn == NULL)
 		return NULL;
 	dn->data = pdn;
 	pdn->phb = hose;
 	pdn->pe_number = IODA_INVALID_PE;
 	regs = of_get_property(dn, "reg", NULL);
 	if (regs) {
 		u32 addr = of_read_number(regs, 1);

 		/* First register entry is addr (00BBSS00)  */
 		pdn->busno = (addr >> 16) & 0xff;
 		pdn->devfn = (addr >> 8) & 0xff;
 	}

 	/* vendor/device IDs and class code */
 	regs = of_get_property(dn, "vendor-id", NULL);
 	pdn->vendor_id = regs ? of_read_number(regs, 1) : 0;
 	regs = of_get_property(dn, "device-id", NULL);
 	pdn->device_id = regs ? of_read_number(regs, 1) : 0;
 	regs = of_get_property(dn, "class-code", NULL);
 	pdn->class_code = regs ? of_read_number(regs, 1) : 0;

 	/* Extended config space */
 	pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);

 	/* Create EEH device */
 #ifdef CONFIG_EEH
 	edev = eeh_dev_init(pdn);
 	if (!edev) {
 		kfree(pdn);
 		return NULL;
 	}
 #endif

 	/* Attach to parent node */
 	INIT_LIST_HEAD(&pdn->child_list);
 	INIT_LIST_HEAD(&pdn->list);
 	parent = of_get_parent(dn);
 	pdn->parent = parent ? PCI_DN(parent) : NULL;
 	if (pdn->parent)
 		list_add_tail(&pdn->list, &pdn->parent->child_list);

 	return pdn;
 }
 EXPORT_SYMBOL_GPL(pci_add_device_node_info);

 void pci_remove_device_node_info(struct device_node *dn)
 {
 	struct pci_dn *pdn = dn ? PCI_DN(dn) : NULL;
 	struct device_node *parent;
 	struct pci_dev *pdev;
 #ifdef CONFIG_EEH
 	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);

 	if (edev)
 		edev->pdn = NULL;
 #endif

 	if (!pdn)
 		return;

 	WARN_ON(!list_empty(&pdn->child_list));
 	list_del(&pdn->list);

 	/* Drop the parent pci_dn's ref to our backing dt node */
 	parent = of_get_parent(dn);
 	if (parent)
 		of_node_put(parent);

 	/*
 	 * At this point we *might* still have a pci_dev that was
 	 * instantiated from this pci_dn. So defer free()ing it until
 	 * the pci_dev's release function is called.
 	 */
 	pdev = pci_get_domain_bus_and_slot(pdn->phb->global_number,
 			pdn->busno, pdn->devfn);
 	if (pdev) {
 		/* NB: pdev has a ref to dn */
 		pci_dbg(pdev, "marked pdn (from %pOF) as dead\n", dn);
 		pdn->flags |= PCI_DN_FLAG_DEAD;
 	} else {
 		dn->data = NULL;
 		kfree(pdn);
 	}

 	pci_dev_put(pdev);
 }
 EXPORT_SYMBOL_GPL(pci_remove_device_node_info);

 /*
  * Traverse a device tree stopping each PCI device in the tree.
  * This is done depth first.  As each node is processed, a "pre"
  * function is called and the children are processed recursively.
  *
  * The "pre" func returns a value.  If non-zero is returned from
  * the "pre" func, the traversal stops and this value is returned.
  * This return value is useful when using traverse as a method of
  * finding a device.
  *
  * NOTE: we do not run the func for devices that do not appear to
  * be PCI except for the start node which we assume (this is good
  * because the start node is often a phb which may be missing PCI
  * properties).
  * We use the class-code as an indicator. If we run into
  * one of these nodes we also assume its siblings are non-pci for
  * performance.
  */
 void *pci_traverse_device_nodes(struct device_node *start,
 				void *(*fn)(struct device_node *, void *),
 				void *data)
 {
 	struct device_node *dn, *nextdn;
 	void *ret;

 	/* We started with a phb, iterate all childs */
 	for (dn = start->child; dn; dn = nextdn) {
 		const __be32 *classp;
 		u32 class = 0;

 		nextdn = NULL;
 		classp = of_get_property(dn, "class-code", NULL);
 		if (classp)
 			class = of_read_number(classp, 1);

 		if (fn) {
 			ret = fn(dn, data);
 			if (ret)
 				return ret;
 		}

 		/* If we are a PCI bridge, go down */
 		if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI ||
 				  (class >> 8) == PCI_CLASS_BRIDGE_CARDBUS))
 			/* Depth first...do children */
 			nextdn = dn->child;
 		else if (dn->sibling)
 			/* ok, try next sibling instead. */
 			nextdn = dn->sibling;
 		if (!nextdn) {
 			/* Walk up to next valid sibling. */
 			do {
 				dn = dn->parent;
 				if (dn == start)
 					return NULL;
 			} while (dn->sibling == NULL);
 			nextdn = dn->sibling;
 		}
 	}
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(pci_traverse_device_nodes);

 static struct pci_dn *pci_dn_next_one(struct pci_dn *root,
 				      struct pci_dn *pdn)
 {
 	struct list_head *next = pdn->child_list.next;

 	if (next != &pdn->child_list)
 		return list_entry(next, struct pci_dn, list);

 	while (1) {
 		if (pdn == root)
 			return NULL;

 		next = pdn->list.next;
 		if (next != &pdn->parent->child_list)
 			break;

 		pdn = pdn->parent;
 	}

 	return list_entry(next, struct pci_dn, list);
 }

 void *traverse_pci_dn(struct pci_dn *root,
 		      void *(*fn)(struct pci_dn *, void *),
 		      void *data)
 {
 	struct pci_dn *pdn = root;
 	void *ret;

 	/* Only scan the child nodes */
 	for (pdn = pci_dn_next_one(root, pdn); pdn;
 	     pdn = pci_dn_next_one(root, pdn)) {
 		ret = fn(pdn, data);
 		if (ret)
 			return ret;
 	}

 	return NULL;
 }

 static void *add_pdn(struct device_node *dn, void *data)
 {
 	struct pci_controller *hose = data;
 	struct pci_dn *pdn;

 	pdn = pci_add_device_node_info(hose, dn);
 	if (!pdn)
 		return ERR_PTR(-ENOMEM);

 	return NULL;
 }

 /**
  * pci_devs_phb_init_dynamic - setup pci devices under this PHB
  * phb: pci-to-host bridge (top-level bridge connecting to cpu)
  *
  * This routine is called both during boot, (before the memory
  * subsystem is set up, before kmalloc is valid) and during the
  * dynamic lpar operation of adding a PHB to a running system.
  */
 void pci_devs_phb_init_dynamic(struct pci_controller *phb)
 {
 	struct device_node *dn = phb->dn;
 	struct pci_dn *pdn;

 	/* PHB nodes themselves must not match */
 	pdn = pci_add_device_node_info(phb, dn);
 	if (pdn) {
 		pdn->devfn = pdn->busno = -1;
 		pdn->vendor_id = pdn->device_id = pdn->class_code = 0;
 		pdn->phb = phb;
 		phb->pci_data = pdn;
 	}

 	/* Update dn->phb ptrs for new phb and children devices */
 	pci_traverse_device_nodes(dn, add_pdn, phb);
 }

 /**
  * pci_devs_phb_init - Initialize phbs and pci devs under them.
  *
  * This routine walks over all phb's (pci-host bridges) on the
  * system, and sets up assorted pci-related structures
  * (including pci info in the device node structs) for each
  * pci device found underneath.  This routine runs once,
  * early in the boot sequence.
  */
 static int __init pci_devs_phb_init(void)
 {
 	struct pci_controller *phb, *tmp;

 	/* This must be done first so the device nodes have valid pci info! */
 	list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
 		pci_devs_phb_init_dynamic(phb);

 	return 0;
 }

 core_initcall(pci_devs_phb_init);

 static void pci_dev_pdn_setup(struct pci_dev *pdev)
 {
 	struct pci_dn *pdn;

 	if (pdev->dev.archdata.pci_data)
 		return;

 	/* Setup the fast path */
 	pdn = pci_get_pdn(pdev);
 	pdev->dev.archdata.pci_data = pdn;
 }
 DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pci_dev_pdn_setup);
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* pci_dn.c
	*
	* Copyright (C) 2001 Todd Inglett, IBM Corporation
	*
	* PCI manipulation via device_nodes.
	*/
	#include <linux/kernel.h>
	#include <linux/pci.h>
	#include <linux/string.h>
	#include <linux/export.h>
	#include <linux/init.h>
	#include <linux/gfp.h>

	#include <asm/io.h>
	#include <asm/prom.h>
	#include <asm/pci-bridge.h>
	#include <asm/ppc-pci.h>
	#include <asm/firmware.h>
	#include <asm/eeh.h>

	/*
	* The function is used to find the firmware data of one
	* specific PCI device, which is attached to the indicated
	* PCI bus. For VFs, their firmware data is linked to that
	* one of PF's bridge. For other devices, their firmware
	* data is linked to that of their bridge.
	*/
	static struct pci_dn pci_bus_to_pdn(struct pci_bus bus)
	{
	struct pci_bus *pbus;
	struct device_node *dn;
	struct pci_dn *pdn;

	/*
	* We probably have virtual bus which doesn't
	* have associated bridge.
	*/
	pbus = bus;
	while (pbus) {
	if (pci_is_root_bus(pbus) \|\| pbus->self)
	break;

	pbus = pbus->parent;
	}

	/*
	* Except virtual bus, all PCI buses should
	* have device nodes.
	*/
	dn = pci_bus_to_OF_node(pbus);
	pdn = dn ? PCI_DN(dn) : NULL;

	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;

	/* Fast path: fetch from PCI device */
	list_for_each_entry(pdev, &bus->devices, bus_list) {
	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)
	return NULL;

	list_for_each_entry(pdn, &parent->child_list, list) {
	if (pdn->busno == bus->number &&
	pdn->devfn == devfn)
	return pdn;
	}

	return NULL;
	}

	struct pci_dn pci_get_pdn(struct pci_dev pdev)
	{
	struct device_node *dn;
	struct pci_dn parent, pdn;

	/* Search device directly */
	if (pdev->dev.archdata.pci_data)
	return pdev->dev.archdata.pci_data;

	/* Check device node */
	dn = pci_device_to_OF_node(pdev);
	pdn = dn ? PCI_DN(dn) : NULL;
	if (pdn)
	return pdn;

	/*
	* VFs don't have device nodes. We hook their
	* firmware data to PF's bridge.
	*/
	parent = pci_bus_to_pdn(pdev->bus);
	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;
	}

	#ifdef CONFIG_PCI_IOV
	static struct pci_dn add_one_sriov_vf_pdn(struct pci_dn parent,
	int vf_index,
	int busno, int devfn)
	{
	struct pci_dn *pdn;

	/* Except PHB, we always have the parent */
	if (!parent)
	return NULL;

	pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
	if (!pdn)
	return NULL;

	pdn->phb = parent->phb;
	pdn->parent = parent;
	pdn->busno = busno;
	pdn->devfn = devfn;
	pdn->vf_index = vf_index;
	pdn->pe_number = IODA_INVALID_PE;
	INIT_LIST_HEAD(&pdn->child_list);
	INIT_LIST_HEAD(&pdn->list);
	list_add_tail(&pdn->list, &parent->child_list);

	return pdn;
	}

	struct pci_dn add_sriov_vf_pdns(struct pci_dev pdev)
	{
	struct pci_dn parent, pdn;
	int i;

	/* Only support IOV for now */
	if (WARN_ON(!pdev->is_physfn))
	return NULL;

	/* Check if VFs have been populated */
	pdn = pci_get_pdn(pdev);
	if (!pdn \|\| (pdn->flags & PCI_DN_FLAG_IOV_VF))
	return NULL;

	pdn->flags \|= PCI_DN_FLAG_IOV_VF;
	parent = pci_bus_to_pdn(pdev->bus);
	if (!parent)
	return NULL;

	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
	struct eeh_dev *edev __maybe_unused;

	pdn = add_one_sriov_vf_pdn(parent, i,
	pci_iov_virtfn_bus(pdev, i),
	pci_iov_virtfn_devfn(pdev, i));
	if (!pdn) {
	dev_warn(&pdev->dev, "%s: Cannot create firmware data for VF#%d\n",
	__func__, i);
	return NULL;
	}

	#ifdef CONFIG_EEH
	/* Create the EEH device for the VF */
	edev = eeh_dev_init(pdn);
	BUG_ON(!edev);
	edev->physfn = pdev;
	#endif /* CONFIG_EEH */
	}
	return pci_get_pdn(pdev);
	}

	void remove_sriov_vf_pdns(struct pci_dev *pdev)
	{
	struct pci_dn *parent;
	struct pci_dn pdn, tmp;
	int i;

	/* Only support IOV PF for now */
	if (WARN_ON(!pdev->is_physfn))
	return;

	/* Check if VFs have been populated */
	pdn = pci_get_pdn(pdev);
	if (!pdn \|\| !(pdn->flags & PCI_DN_FLAG_IOV_VF))
	return;

	pdn->flags &= ~PCI_DN_FLAG_IOV_VF;
	parent = pci_bus_to_pdn(pdev->bus);
	if (!parent)
	return;

	/*
	* We might introduce flag to pci_dn in future
	* so that we can release VF's firmware data in
	* a batch mode.
	*/
	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
	struct eeh_dev *edev __maybe_unused;

	list_for_each_entry_safe(pdn, tmp,
	&parent->child_list, list) {
	if (pdn->busno != pci_iov_virtfn_bus(pdev, i) \|\|
	pdn->devfn != pci_iov_virtfn_devfn(pdev, i))
	continue;

	#ifdef CONFIG_EEH
	/*
	* Release EEH state for this VF. The PCI core
	* has already torn down the pci_dev for this VF, but
	* we're responsible to removing the eeh_dev since it
	* has the same lifetime as the pci_dn that spawned it.
	*/
	edev = pdn_to_eeh_dev(pdn);
	if (edev) {
	/*
	* We allocate pci_dn's for the totalvfs count,
	* but only only the vfs that were activated
	* have a configured PE.
	*/
	if (edev->pe)
	eeh_rmv_from_parent_pe(edev);

	pdn->edev = NULL;
	kfree(edev);
	}
	#endif /* CONFIG_EEH */

	if (!list_empty(&pdn->list))
	list_del(&pdn->list);

	kfree(pdn);
	}
	}
	}
	#endif /* CONFIG_PCI_IOV */

	struct pci_dn pci_add_device_node_info(struct pci_controller hose,
	struct device_node *dn)
	{
	const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL);
	const __be32 *regs;
	struct device_node *parent;
	struct pci_dn *pdn;
	#ifdef CONFIG_EEH
	struct eeh_dev *edev;
	#endif

	pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
	if (pdn == NULL)
	return NULL;
	dn->data = pdn;
	pdn->phb = hose;
	pdn->pe_number = IODA_INVALID_PE;
	regs = of_get_property(dn, "reg", NULL);
	if (regs) {
	u32 addr = of_read_number(regs, 1);

	/* First register entry is addr (00BBSS00) */
	pdn->busno = (addr >> 16) & 0xff;
	pdn->devfn = (addr >> 8) & 0xff;
	}

	/* vendor/device IDs and class code */
	regs = of_get_property(dn, "vendor-id", NULL);
	pdn->vendor_id = regs ? of_read_number(regs, 1) : 0;
	regs = of_get_property(dn, "device-id", NULL);
	pdn->device_id = regs ? of_read_number(regs, 1) : 0;
	regs = of_get_property(dn, "class-code", NULL);
	pdn->class_code = regs ? of_read_number(regs, 1) : 0;

	/* Extended config space */
	pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);

	/* Create EEH device */
	#ifdef CONFIG_EEH
	edev = eeh_dev_init(pdn);
	if (!edev) {
	kfree(pdn);
	return NULL;
	}
	#endif

	/* Attach to parent node */
	INIT_LIST_HEAD(&pdn->child_list);
	INIT_LIST_HEAD(&pdn->list);
	parent = of_get_parent(dn);
	pdn->parent = parent ? PCI_DN(parent) : NULL;
	if (pdn->parent)
	list_add_tail(&pdn->list, &pdn->parent->child_list);

	return pdn;
	}
	EXPORT_SYMBOL_GPL(pci_add_device_node_info);

	void pci_remove_device_node_info(struct device_node *dn)
	{
	struct pci_dn *pdn = dn ? PCI_DN(dn) : NULL;
	struct device_node *parent;
	struct pci_dev *pdev;
	#ifdef CONFIG_EEH
	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);

	if (edev)
	edev->pdn = NULL;
	#endif

	if (!pdn)
	return;

	WARN_ON(!list_empty(&pdn->child_list));
	list_del(&pdn->list);

	/* Drop the parent pci_dn's ref to our backing dt node */
	parent = of_get_parent(dn);
	if (parent)
	of_node_put(parent);

	/*
	* At this point we might still have a pci_dev that was
	* instantiated from this pci_dn. So defer free()ing it until
	* the pci_dev's release function is called.
	*/
	pdev = pci_get_domain_bus_and_slot(pdn->phb->global_number,
	pdn->busno, pdn->devfn);
	if (pdev) {
	/* NB: pdev has a ref to dn */
	pci_dbg(pdev, "marked pdn (from %pOF) as dead\n", dn);
	pdn->flags \|= PCI_DN_FLAG_DEAD;
	} else {
	dn->data = NULL;
	kfree(pdn);
	}

	pci_dev_put(pdev);
	}
	EXPORT_SYMBOL_GPL(pci_remove_device_node_info);

	/*
	* Traverse a device tree stopping each PCI device in the tree.
	* This is done depth first. As each node is processed, a "pre"
	* function is called and the children are processed recursively.
	*
	* The "pre" func returns a value. If non-zero is returned from
	* the "pre" func, the traversal stops and this value is returned.
	* This return value is useful when using traverse as a method of
	* finding a device.
	*
	* NOTE: we do not run the func for devices that do not appear to
	* be PCI except for the start node which we assume (this is good
	* because the start node is often a phb which may be missing PCI
	* properties).
	* We use the class-code as an indicator. If we run into
	* one of these nodes we also assume its siblings are non-pci for
	* performance.
	*/
	void pci_traverse_device_nodes(struct device_node start,
	void (fn)(struct device_node , void ),
	void *data)
	{
	struct device_node dn, nextdn;
	void *ret;

	/* We started with a phb, iterate all childs */
	for (dn = start->child; dn; dn = nextdn) {
	const __be32 *classp;
	u32 class = 0;

	nextdn = NULL;
	classp = of_get_property(dn, "class-code", NULL);
	if (classp)
	class = of_read_number(classp, 1);

	if (fn) {
	ret = fn(dn, data);
	if (ret)
	return ret;
	}

	/* If we are a PCI bridge, go down */
	if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI \|\|
	(class >> 8) == PCI_CLASS_BRIDGE_CARDBUS))
	/* Depth first...do children */
	nextdn = dn->child;
	else if (dn->sibling)
	/* ok, try next sibling instead. */
	nextdn = dn->sibling;
	if (!nextdn) {
	/* Walk up to next valid sibling. */
	do {
	dn = dn->parent;
	if (dn == start)
	return NULL;
	} while (dn->sibling == NULL);
	nextdn = dn->sibling;
	}
	}
	return NULL;
	}
	EXPORT_SYMBOL_GPL(pci_traverse_device_nodes);

	static struct pci_dn pci_dn_next_one(struct pci_dn root,
	struct pci_dn *pdn)
	{
	struct list_head *next = pdn->child_list.next;

	if (next != &pdn->child_list)
	return list_entry(next, struct pci_dn, list);

	while (1) {
	if (pdn == root)
	return NULL;

	next = pdn->list.next;
	if (next != &pdn->parent->child_list)
	break;

	pdn = pdn->parent;
	}

	return list_entry(next, struct pci_dn, list);
	}

	void traverse_pci_dn(struct pci_dn root,
	void (fn)(struct pci_dn , void ),
	void *data)
	{
	struct pci_dn *pdn = root;
	void *ret;

	/* Only scan the child nodes */
	for (pdn = pci_dn_next_one(root, pdn); pdn;
	pdn = pci_dn_next_one(root, pdn)) {
	ret = fn(pdn, data);
	if (ret)
	return ret;
	}

	return NULL;
	}

	static void add_pdn(struct device_node dn, void *data)
	{
	struct pci_controller *hose = data;
	struct pci_dn *pdn;

	pdn = pci_add_device_node_info(hose, dn);
	if (!pdn)
	return ERR_PTR(-ENOMEM);

	return NULL;
	}

	/**
	* pci_devs_phb_init_dynamic - setup pci devices under this PHB
	* phb: pci-to-host bridge (top-level bridge connecting to cpu)
	*
	* This routine is called both during boot, (before the memory
	* subsystem is set up, before kmalloc is valid) and during the
	* dynamic lpar operation of adding a PHB to a running system.
	*/
	void pci_devs_phb_init_dynamic(struct pci_controller *phb)
	{
	struct device_node *dn = phb->dn;
	struct pci_dn *pdn;

	/* PHB nodes themselves must not match */
	pdn = pci_add_device_node_info(phb, dn);
	if (pdn) {
	pdn->devfn = pdn->busno = -1;
	pdn->vendor_id = pdn->device_id = pdn->class_code = 0;
	pdn->phb = phb;
	phb->pci_data = pdn;
	}

	/* Update dn->phb ptrs for new phb and children devices */
	pci_traverse_device_nodes(dn, add_pdn, phb);
	}

	/**
	* pci_devs_phb_init - Initialize phbs and pci devs under them.
	*
	* This routine walks over all phb's (pci-host bridges) on the
	* system, and sets up assorted pci-related structures
	* (including pci info in the device node structs) for each
	* pci device found underneath. This routine runs once,
	* early in the boot sequence.
	*/
	static int __init pci_devs_phb_init(void)
	{
	struct pci_controller phb, tmp;

	/* This must be done first so the device nodes have valid pci info! */
	list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
	pci_devs_phb_init_dynamic(phb);

	return 0;
	}

	core_initcall(pci_devs_phb_init);

	static void pci_dev_pdn_setup(struct pci_dev *pdev)
	{
	struct pci_dn *pdn;

	if (pdev->dev.archdata.pci_data)
	return;

	/* Setup the fast path */
	pdn = pci_get_pdn(pdev);
	pdev->dev.archdata.pci_data = pdn;
	}
	DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pci_dev_pdn_setup);