xref: /openbmc/linux/drivers/pci/of.c (revision 588b48ca)
1 /*
2  * PCI <-> OF mapping helpers
3  *
4  * Copyright 2011 IBM Corp.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/pci.h>
14 #include <linux/of.h>
15 #include <linux/of_pci.h>
16 #include "pci.h"
17 
18 void pci_set_of_node(struct pci_dev *dev)
19 {
20 	if (!dev->bus->dev.of_node)
21 		return;
22 	dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
23 						    dev->devfn);
24 }
25 
26 void pci_release_of_node(struct pci_dev *dev)
27 {
28 	of_node_put(dev->dev.of_node);
29 	dev->dev.of_node = NULL;
30 }
31 
32 void pci_set_bus_of_node(struct pci_bus *bus)
33 {
34 	if (bus->self == NULL)
35 		bus->dev.of_node = pcibios_get_phb_of_node(bus);
36 	else
37 		bus->dev.of_node = of_node_get(bus->self->dev.of_node);
38 }
39 
40 void pci_release_bus_of_node(struct pci_bus *bus)
41 {
42 	of_node_put(bus->dev.of_node);
43 	bus->dev.of_node = NULL;
44 }
45 
46 struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
47 {
48 	/* This should only be called for PHBs */
49 	if (WARN_ON(bus->self || bus->parent))
50 		return NULL;
51 
52 	/* Look for a node pointer in either the intermediary device we
53 	 * create above the root bus or it's own parent. Normally only
54 	 * the later is populated.
55 	 */
56 	if (bus->bridge->of_node)
57 		return of_node_get(bus->bridge->of_node);
58 	if (bus->bridge->parent && bus->bridge->parent->of_node)
59 		return of_node_get(bus->bridge->parent->of_node);
60 	return NULL;
61 }
62