summaryrefslogtreecommitdiff
path: root/drivers/acpi/pci_slot.c
blob: ca2461d1bf14e0ccee361060bbf4096dbf334d40 (plain)
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
// SPDX-License-Identifier: GPL-2.0-only
/*
 *  pci_slot.c - ACPI PCI Slot Driver
 *
 *  The code here is heavily leveraged from the acpiphp module.
 *  Thanks to Matthew Wilcox <matthew@wil.cx> for much guidance.
 *  Thanks to Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> for code
 *  review and fixes.
 *
 *  Copyright (C) 2007-2008 Hewlett-Packard Development Company, L.P.
 *  	Alex Chiang <achiang@hp.com>
 *
 *  Copyright (C) 2013 Huawei Tech. Co., Ltd.
 *	Jiang Liu <jiang.liu@huawei.com>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/dmi.h>
#include <linux/pci-acpi.h>

static int check_sta_before_sun;

#define _COMPONENT		ACPI_PCI_COMPONENT
ACPI_MODULE_NAME("pci_slot");

#define SLOT_NAME_SIZE 21		/* Inspired by #define in acpiphp.h */

struct acpi_pci_slot {
	struct pci_slot *pci_slot;	/* corresponding pci_slot */
	struct list_head list;		/* node in the list of slots */
};

static LIST_HEAD(slot_list);
static DEFINE_MUTEX(slot_list_lock);

static int
check_slot(acpi_handle handle, unsigned long long *sun)
{
	int device = -1;
	unsigned long long adr, sta;
	acpi_status status;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };

	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
	pr_debug("Checking slot on path: %s\n", (char *)buffer.pointer);

	if (check_sta_before_sun) {
		/* If SxFy doesn't have _STA, we just assume it's there */
		status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
		if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_PRESENT))
			goto out;
	}

	status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
	if (ACPI_FAILURE(status)) {
		pr_debug("_ADR returned %d on %s\n",
			 status, (char *)buffer.pointer);
		goto out;
	}

	/* No _SUN == not a slot == bail */
	status = acpi_evaluate_integer(handle, "_SUN", NULL, sun);
	if (ACPI_FAILURE(status)) {
		pr_debug("_SUN returned %d on %s\n",
			 status, (char *)buffer.pointer);
		goto out;
	}

	device = (adr >> 16) & 0xffff;
out:
	kfree(buffer.pointer);
	return device;
}

/*
 * Check whether handle has an associated slot and create PCI slot if it has.
 */
static acpi_status
register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
{
	int device;
	unsigned long long sun;
	char name[SLOT_NAME_SIZE];
	struct acpi_pci_slot *slot;
	struct pci_slot *pci_slot;
	struct pci_bus *pci_bus = context;

	device = check_slot(handle, &sun);
	if (device < 0)
		return AE_OK;

	/*
	 * There may be multiple PCI functions associated with the same slot.
	 * Check whether PCI slot has already been created for this PCI device.
	 */
	list_for_each_entry(slot, &slot_list, list) {
		pci_slot = slot->pci_slot;
		if (pci_slot->bus == pci_bus && pci_slot->number == device)
			return AE_OK;
	}

	slot = kmalloc(sizeof(*slot), GFP_KERNEL);
	if (!slot)
		return AE_OK;

	snprintf(name, sizeof(name), "%llu", sun);
	pci_slot = pci_create_slot(pci_bus, device, name, NULL);
	if (IS_ERR(pci_slot)) {
		pr_err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot));
		kfree(slot);
		return AE_OK;
	}

	slot->pci_slot = pci_slot;
	list_add(&slot->list, &slot_list);

	get_device(&pci_bus->dev);

	pr_debug("%p, pci_bus: %x, device: %d, name: %s\n",
		 pci_slot, pci_bus->number, device, name);

	return AE_OK;
}

void acpi_pci_slot_enumerate(struct pci_bus *bus)
{
	acpi_handle handle = ACPI_HANDLE(bus->bridge);

	if (handle) {
		mutex_lock(&slot_list_lock);
		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
				    register_slot, NULL, bus, NULL);
		mutex_unlock(&slot_list_lock);
	}
}

void acpi_pci_slot_remove(struct pci_bus *bus)
{
	struct acpi_pci_slot *slot, *tmp;

	mutex_lock(&slot_list_lock);
	list_for_each_entry_safe(slot, tmp, &slot_list, list) {
		if (slot->pci_slot->bus == bus) {
			list_del(&slot->list);
			pci_destroy_slot(slot->pci_slot);
			put_device(&bus->dev);
			kfree(slot);
		}
	}
	mutex_unlock(&slot_list_lock);
}

static int do_sta_before_sun(const struct dmi_system_id *d)
{
	pr_info("%s detected: will evaluate _STA before calling _SUN\n",
		d->ident);
	check_sta_before_sun = 1;
	return 0;
}

static const struct dmi_system_id acpi_pci_slot_dmi_table[] __initconst = {
	/*
	 * Fujitsu Primequest machines will return 1023 to indicate an
	 * error if the _SUN method is evaluated on SxFy objects that
	 * are not present (as indicated by _STA), so for those machines,
	 * we want to check _STA before evaluating _SUN.
	 */
	{
	 .callback = do_sta_before_sun,
	 .ident = "Fujitsu PRIMEQUEST",
	 .matches = {
		DMI_MATCH(DMI_BIOS_VENDOR, "FUJITSU LIMITED"),
		DMI_MATCH(DMI_BIOS_VERSION, "PRIMEQUEST"),
		},
	},
	{}
};

void __init acpi_pci_slot_init(void)
{
	dmi_check_system(acpi_pci_slot_dmi_table);
}