aboutsummaryrefslogtreecommitdiffstats
path: root/arch/ppc64/kernel/pci_dn.c
blob: ec345462afc3f2660a5b5b541fdce902bf96a93d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
/*
 * pci_dn.c
 *
 * Copyright (C) 2001 Todd Inglett, IBM Corporation
 *
 * PCI manipulation via device_nodes.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *    
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/init.h>

#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/pSeries_reconfig.h>

#include "pci.h"

/*
 * Traverse_func that inits the PCI fields of the device node.
 * NOTE: this *must* be done before read/write config to the device.
 */
static void * __devinit update_dn_pci_info(struct device_node *dn, void *data)
{
	struct pci_controller *phb = data;
	int *type = (int *)get_property(dn, "ibm,pci-config-space-type", NULL);
	u32 *regs;

	dn->phb = phb;
	regs = (u32 *)get_property(dn, "reg", NULL);
	if (regs) {
		/* First register entry is addr (00BBSS00)  */
		dn->busno = (regs[0] >> 16) & 0xff;
		dn->devfn = (regs[0] >> 8) & 0xff;
	}

	dn->pci_ext_config_space = (type && *type == 1);
	return NULL;
}

/*
 * 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 *traverse_pci_devices(struct device_node *start, traverse_func pre,
		void *data)
{
	struct device_node *dn, *nextdn;
	void *ret;

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

		nextdn = NULL;
		classp = (u32 *)get_property(dn, "class-code", NULL);
		class = classp ? *classp : 0;

		if (pre && ((ret = pre(dn, data)) != NULL))
			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;
}

void __devinit pci_devs_phb_init_dynamic(struct pci_controller *phb)
{
	struct device_node * dn = (struct device_node *) phb->arch_data;

	/* PHB nodes themselves must not match */
	dn->devfn = dn->busno = -1;
	dn->phb = phb;

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

/*
 * Traversal func that looks for a <busno,devfcn> value.
 * If found, the device_node is returned (thus terminating the traversal).
 */
static void *is_devfn_node(struct device_node *dn, void *data)
{
	int busno = ((unsigned long)data >> 8) & 0xff;
	int devfn = ((unsigned long)data) & 0xff;

	return ((devfn == dn->devfn) && (busno == dn->busno)) ? dn : NULL;
}

/*
 * This is the "slow" path for looking up a device_node from a
 * pci_dev.  It will hunt for the device under its parent's
 * phb and then update sysdata for a future fastpath.
 *
 * It may also do fixups on the actual device since this happens
 * on the first read/write.
 *
 * Note that it also must deal with devices that don't exist.
 * In this case it may probe for real hardware ("just in case")
 * and add a device_node to the device tree if necessary.
 *
 */
struct device_node *fetch_dev_dn(struct pci_dev *dev)
{
	struct device_node *orig_dn = dev->sysdata;
	struct pci_controller *phb = orig_dn->phb; /* assume same phb as orig_dn */
	struct device_node *phb_dn;
	struct device_node *dn;
	unsigned long searchval = (dev->bus->number << 8) | dev->devfn;

	phb_dn = phb->arch_data;
	dn = traverse_pci_devices(phb_dn, is_devfn_node, (void *)searchval);
	if (dn)
		dev->sysdata = dn;
	return dn;
}
EXPORT_SYMBOL(fetch_dev_dn);

static int pci_dn_reconfig_notifier(struct notifier_block *nb, unsigned long action, void *node)
{
	struct device_node *np = node;
	int err = NOTIFY_OK;

	switch (action) {
	case PSERIES_RECONFIG_ADD:
		update_dn_pci_info(np, np->parent->phb);
		break;
	default:
		err = NOTIFY_DONE;
		break;
	}
	return err;
}

static struct notifier_block pci_dn_reconfig_nb = {
	.notifier_call = pci_dn_reconfig_notifier,
};

/*
 * Actually initialize the phbs.
 * The buswalk on this phb has not happened yet.
 */
void __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);

	pSeries_reconfig_notifier_register(&pci_dn_reconfig_nb);
}