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1/*
2 * pci_slot.c - ACPI PCI Slot Driver
3 *
4 * The code here is heavily leveraged from the acpiphp module.
5 * Thanks to Matthew Wilcox <matthew@wil.cx> for much guidance.
6 * Thanks to Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> for code
7 * review and fixes.
8 *
9 * Copyright (C) 2007-2008 Hewlett-Packard Development Company, L.P.
10 * Alex Chiang <achiang@hp.com>
11 *
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms and conditions of the GNU General Public License,
14 * version 2, as published by the Free Software Foundation.
15 *
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License along
22 * with this program; if not, write to the Free Software Foundation, Inc.,
23 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
24 */
25
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/init.h>
29#include <linux/slab.h>
30#include <linux/types.h>
31#include <linux/pci.h>
32#include <linux/acpi.h>
33#include <acpi/acpi_bus.h>
34#include <acpi/acpi_drivers.h>
35#include <linux/dmi.h>
36
37static int debug;
38static int check_sta_before_sun;
39
40#define DRIVER_VERSION "0.1"
41#define DRIVER_AUTHOR "Alex Chiang <achiang@hp.com>"
42#define DRIVER_DESC "ACPI PCI Slot Detection Driver"
43MODULE_AUTHOR(DRIVER_AUTHOR);
44MODULE_DESCRIPTION(DRIVER_DESC);
45MODULE_LICENSE("GPL");
46MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
47module_param(debug, bool, 0644);
48
49#define _COMPONENT ACPI_PCI_COMPONENT
50ACPI_MODULE_NAME("pci_slot");
51
52#define MY_NAME "pci_slot"
53#define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg)
54#define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg)
55#define dbg(format, arg...) \
56 do { \
57 if (debug) \
58 printk(KERN_DEBUG "%s: " format, \
59 MY_NAME , ## arg); \
60 } while (0)
61
62#define SLOT_NAME_SIZE 21 /* Inspired by #define in acpiphp.h */
63
64struct acpi_pci_slot {
65 acpi_handle root_handle; /* handle of the root bridge */
66 struct pci_slot *pci_slot; /* corresponding pci_slot */
67 struct list_head list; /* node in the list of slots */
68};
69
70static int acpi_pci_slot_add(acpi_handle handle);
71static void acpi_pci_slot_remove(acpi_handle handle);
72
73static LIST_HEAD(slot_list);
74static DEFINE_MUTEX(slot_list_lock);
75static struct acpi_pci_driver acpi_pci_slot_driver = {
76 .add = acpi_pci_slot_add,
77 .remove = acpi_pci_slot_remove,
78};
79
80static int
81check_slot(acpi_handle handle, unsigned long long *sun)
82{
83 int device = -1;
84 unsigned long long adr, sta;
85 acpi_status status;
86 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
87
88 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
89 dbg("Checking slot on path: %s\n", (char *)buffer.pointer);
90
91 if (check_sta_before_sun) {
92 /* If SxFy doesn't have _STA, we just assume it's there */
93 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
94 if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_PRESENT))
95 goto out;
96 }
97
98 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
99 if (ACPI_FAILURE(status)) {
100 dbg("_ADR returned %d on %s\n", status, (char *)buffer.pointer);
101 goto out;
102 }
103
104 /* No _SUN == not a slot == bail */
105 status = acpi_evaluate_integer(handle, "_SUN", NULL, sun);
106 if (ACPI_FAILURE(status)) {
107 dbg("_SUN returned %d on %s\n", status, (char *)buffer.pointer);
108 goto out;
109 }
110
111 device = (adr >> 16) & 0xffff;
112out:
113 kfree(buffer.pointer);
114 return device;
115}
116
117struct callback_args {
118 acpi_walk_callback user_function; /* only for walk_p2p_bridge */
119 struct pci_bus *pci_bus;
120 acpi_handle root_handle;
121};
122
123/*
124 * register_slot
125 *
126 * Called once for each SxFy object in the namespace. Don't worry about
127 * calling pci_create_slot multiple times for the same pci_bus:device,
128 * since each subsequent call simply bumps the refcount on the pci_slot.
129 *
130 * The number of calls to pci_destroy_slot from unregister_slot is
131 * symmetrical.
132 */
133static acpi_status
134register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
135{
136 int device;
137 unsigned long long sun;
138 char name[SLOT_NAME_SIZE];
139 struct acpi_pci_slot *slot;
140 struct pci_slot *pci_slot;
141 struct callback_args *parent_context = context;
142 struct pci_bus *pci_bus = parent_context->pci_bus;
143
144 device = check_slot(handle, &sun);
145 if (device < 0)
146 return AE_OK;
147
148 slot = kmalloc(sizeof(*slot), GFP_KERNEL);
149 if (!slot) {
150 err("%s: cannot allocate memory\n", __func__);
151 return AE_OK;
152 }
153
154 snprintf(name, sizeof(name), "%llu", sun);
155 pci_slot = pci_create_slot(pci_bus, device, name, NULL);
156 if (IS_ERR(pci_slot)) {
157 err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot));
158 kfree(slot);
159 return AE_OK;
160 }
161
162 slot->root_handle = parent_context->root_handle;
163 slot->pci_slot = pci_slot;
164 INIT_LIST_HEAD(&slot->list);
165 mutex_lock(&slot_list_lock);
166 list_add(&slot->list, &slot_list);
167 mutex_unlock(&slot_list_lock);
168
169 get_device(&pci_bus->dev);
170
171 dbg("pci_slot: %p, pci_bus: %x, device: %d, name: %s\n",
172 pci_slot, pci_bus->number, device, name);
173
174 return AE_OK;
175}
176
177/*
178 * walk_p2p_bridge - discover and walk p2p bridges
179 * @handle: points to an acpi_pci_root
180 * @context: p2p_bridge_context pointer
181 *
182 * Note that when we call ourselves recursively, we pass a different
183 * value of pci_bus in the child_context.
184 */
185static acpi_status
186walk_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)
187{
188 int device, function;
189 unsigned long long adr;
190 acpi_status status;
191 acpi_handle dummy_handle;
192 acpi_walk_callback user_function;
193
194 struct pci_dev *dev;
195 struct pci_bus *pci_bus;
196 struct callback_args child_context;
197 struct callback_args *parent_context = context;
198
199 pci_bus = parent_context->pci_bus;
200 user_function = parent_context->user_function;
201
202 status = acpi_get_handle(handle, "_ADR", &dummy_handle);
203 if (ACPI_FAILURE(status))
204 return AE_OK;
205
206 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
207 if (ACPI_FAILURE(status))
208 return AE_OK;
209
210 device = (adr >> 16) & 0xffff;
211 function = adr & 0xffff;
212
213 dev = pci_get_slot(pci_bus, PCI_DEVFN(device, function));
214 if (!dev || !dev->subordinate)
215 goto out;
216
217 child_context.pci_bus = dev->subordinate;
218 child_context.user_function = user_function;
219 child_context.root_handle = parent_context->root_handle;
220
221 dbg("p2p bridge walk, pci_bus = %x\n", dev->subordinate->number);
222 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
223 user_function, NULL, &child_context, NULL);
224 if (ACPI_FAILURE(status))
225 goto out;
226
227 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
228 walk_p2p_bridge, NULL, &child_context, NULL);
229out:
230 pci_dev_put(dev);
231 return AE_OK;
232}
233
234/*
235 * walk_root_bridge - generic root bridge walker
236 * @handle: points to an acpi_pci_root
237 * @user_function: user callback for slot objects
238 *
239 * Call user_function for all objects underneath this root bridge.
240 * Walk p2p bridges underneath us and call user_function on those too.
241 */
242static int
243walk_root_bridge(acpi_handle handle, acpi_walk_callback user_function)
244{
245 int seg, bus;
246 unsigned long long tmp;
247 acpi_status status;
248 acpi_handle dummy_handle;
249 struct pci_bus *pci_bus;
250 struct callback_args context;
251
252 /* If the bridge doesn't have _STA, we assume it is always there */
253 status = acpi_get_handle(handle, "_STA", &dummy_handle);
254 if (ACPI_SUCCESS(status)) {
255 status = acpi_evaluate_integer(handle, "_STA", NULL, &tmp);
256 if (ACPI_FAILURE(status)) {
257 info("%s: _STA evaluation failure\n", __func__);
258 return 0;
259 }
260 if ((tmp & ACPI_STA_DEVICE_FUNCTIONING) == 0)
261 /* don't register this object */
262 return 0;
263 }
264
265 status = acpi_evaluate_integer(handle, "_SEG", NULL, &tmp);
266 seg = ACPI_SUCCESS(status) ? tmp : 0;
267
268 status = acpi_evaluate_integer(handle, "_BBN", NULL, &tmp);
269 bus = ACPI_SUCCESS(status) ? tmp : 0;
270
271 pci_bus = pci_find_bus(seg, bus);
272 if (!pci_bus)
273 return 0;
274
275 context.pci_bus = pci_bus;
276 context.user_function = user_function;
277 context.root_handle = handle;
278
279 dbg("root bridge walk, pci_bus = %x\n", pci_bus->number);
280 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
281 user_function, NULL, &context, NULL);
282 if (ACPI_FAILURE(status))
283 return status;
284
285 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
286 walk_p2p_bridge, NULL, &context, NULL);
287 if (ACPI_FAILURE(status))
288 err("%s: walk_p2p_bridge failure - %d\n", __func__, status);
289
290 return status;
291}
292
293/*
294 * acpi_pci_slot_add
295 * @handle: points to an acpi_pci_root
296 */
297static int
298acpi_pci_slot_add(acpi_handle handle)
299{
300 acpi_status status;
301
302 status = walk_root_bridge(handle, register_slot);
303 if (ACPI_FAILURE(status))
304 err("%s: register_slot failure - %d\n", __func__, status);
305
306 return status;
307}
308
309/*
310 * acpi_pci_slot_remove
311 * @handle: points to an acpi_pci_root
312 */
313static void
314acpi_pci_slot_remove(acpi_handle handle)
315{
316 struct acpi_pci_slot *slot, *tmp;
317 struct pci_bus *pbus;
318
319 mutex_lock(&slot_list_lock);
320 list_for_each_entry_safe(slot, tmp, &slot_list, list) {
321 if (slot->root_handle == handle) {
322 list_del(&slot->list);
323 pbus = slot->pci_slot->bus;
324 pci_destroy_slot(slot->pci_slot);
325 put_device(&pbus->dev);
326 kfree(slot);
327 }
328 }
329 mutex_unlock(&slot_list_lock);
330}
331
332static int do_sta_before_sun(const struct dmi_system_id *d)
333{
334 info("%s detected: will evaluate _STA before calling _SUN\n", d->ident);
335 check_sta_before_sun = 1;
336 return 0;
337}
338
339static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = {
340 /*
341 * Fujitsu Primequest machines will return 1023 to indicate an
342 * error if the _SUN method is evaluated on SxFy objects that
343 * are not present (as indicated by _STA), so for those machines,
344 * we want to check _STA before evaluating _SUN.
345 */
346 {
347 .callback = do_sta_before_sun,
348 .ident = "Fujitsu PRIMEQUEST",
349 .matches = {
350 DMI_MATCH(DMI_BIOS_VENDOR, "FUJITSU LIMITED"),
351 DMI_MATCH(DMI_BIOS_VERSION, "PRIMEQUEST"),
352 },
353 },
354 {}
355};
356
357static int __init
358acpi_pci_slot_init(void)
359{
360 dmi_check_system(acpi_pci_slot_dmi_table);
361 acpi_pci_register_driver(&acpi_pci_slot_driver);
362 return 0;
363}
364
365static void __exit
366acpi_pci_slot_exit(void)
367{
368 acpi_pci_unregister_driver(&acpi_pci_slot_driver);
369}
370
371module_init(acpi_pci_slot_init);
372module_exit(acpi_pci_slot_exit);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * pci_slot.c - ACPI PCI Slot Driver
4 *
5 * The code here is heavily leveraged from the acpiphp module.
6 * Thanks to Matthew Wilcox <matthew@wil.cx> for much guidance.
7 * Thanks to Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> for code
8 * review and fixes.
9 *
10 * Copyright (C) 2007-2008 Hewlett-Packard Development Company, L.P.
11 * Alex Chiang <achiang@hp.com>
12 *
13 * Copyright (C) 2013 Huawei Tech. Co., Ltd.
14 * Jiang Liu <jiang.liu@huawei.com>
15 */
16
17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19#include <linux/kernel.h>
20#include <linux/init.h>
21#include <linux/slab.h>
22#include <linux/types.h>
23#include <linux/list.h>
24#include <linux/pci.h>
25#include <linux/acpi.h>
26#include <linux/dmi.h>
27#include <linux/pci-acpi.h>
28
29static int check_sta_before_sun;
30
31#define _COMPONENT ACPI_PCI_COMPONENT
32ACPI_MODULE_NAME("pci_slot");
33
34#define SLOT_NAME_SIZE 21 /* Inspired by #define in acpiphp.h */
35
36struct acpi_pci_slot {
37 struct pci_slot *pci_slot; /* corresponding pci_slot */
38 struct list_head list; /* node in the list of slots */
39};
40
41static LIST_HEAD(slot_list);
42static DEFINE_MUTEX(slot_list_lock);
43
44static int
45check_slot(acpi_handle handle, unsigned long long *sun)
46{
47 int device = -1;
48 unsigned long long adr, sta;
49 acpi_status status;
50 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
51
52 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
53 pr_debug("Checking slot on path: %s\n", (char *)buffer.pointer);
54
55 if (check_sta_before_sun) {
56 /* If SxFy doesn't have _STA, we just assume it's there */
57 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
58 if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_PRESENT))
59 goto out;
60 }
61
62 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
63 if (ACPI_FAILURE(status)) {
64 pr_debug("_ADR returned %d on %s\n",
65 status, (char *)buffer.pointer);
66 goto out;
67 }
68
69 /* No _SUN == not a slot == bail */
70 status = acpi_evaluate_integer(handle, "_SUN", NULL, sun);
71 if (ACPI_FAILURE(status)) {
72 pr_debug("_SUN returned %d on %s\n",
73 status, (char *)buffer.pointer);
74 goto out;
75 }
76
77 device = (adr >> 16) & 0xffff;
78out:
79 kfree(buffer.pointer);
80 return device;
81}
82
83/*
84 * Check whether handle has an associated slot and create PCI slot if it has.
85 */
86static acpi_status
87register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
88{
89 int device;
90 unsigned long long sun;
91 char name[SLOT_NAME_SIZE];
92 struct acpi_pci_slot *slot;
93 struct pci_slot *pci_slot;
94 struct pci_bus *pci_bus = context;
95
96 device = check_slot(handle, &sun);
97 if (device < 0)
98 return AE_OK;
99
100 /*
101 * There may be multiple PCI functions associated with the same slot.
102 * Check whether PCI slot has already been created for this PCI device.
103 */
104 list_for_each_entry(slot, &slot_list, list) {
105 pci_slot = slot->pci_slot;
106 if (pci_slot->bus == pci_bus && pci_slot->number == device)
107 return AE_OK;
108 }
109
110 slot = kmalloc(sizeof(*slot), GFP_KERNEL);
111 if (!slot)
112 return AE_OK;
113
114 snprintf(name, sizeof(name), "%llu", sun);
115 pci_slot = pci_create_slot(pci_bus, device, name, NULL);
116 if (IS_ERR(pci_slot)) {
117 pr_err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot));
118 kfree(slot);
119 return AE_OK;
120 }
121
122 slot->pci_slot = pci_slot;
123 list_add(&slot->list, &slot_list);
124
125 get_device(&pci_bus->dev);
126
127 pr_debug("%p, pci_bus: %x, device: %d, name: %s\n",
128 pci_slot, pci_bus->number, device, name);
129
130 return AE_OK;
131}
132
133void acpi_pci_slot_enumerate(struct pci_bus *bus)
134{
135 acpi_handle handle = ACPI_HANDLE(bus->bridge);
136
137 if (handle) {
138 mutex_lock(&slot_list_lock);
139 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
140 register_slot, NULL, bus, NULL);
141 mutex_unlock(&slot_list_lock);
142 }
143}
144
145void acpi_pci_slot_remove(struct pci_bus *bus)
146{
147 struct acpi_pci_slot *slot, *tmp;
148
149 mutex_lock(&slot_list_lock);
150 list_for_each_entry_safe(slot, tmp, &slot_list, list) {
151 if (slot->pci_slot->bus == bus) {
152 list_del(&slot->list);
153 pci_destroy_slot(slot->pci_slot);
154 put_device(&bus->dev);
155 kfree(slot);
156 }
157 }
158 mutex_unlock(&slot_list_lock);
159}
160
161static int do_sta_before_sun(const struct dmi_system_id *d)
162{
163 pr_info("%s detected: will evaluate _STA before calling _SUN\n",
164 d->ident);
165 check_sta_before_sun = 1;
166 return 0;
167}
168
169static const struct dmi_system_id acpi_pci_slot_dmi_table[] __initconst = {
170 /*
171 * Fujitsu Primequest machines will return 1023 to indicate an
172 * error if the _SUN method is evaluated on SxFy objects that
173 * are not present (as indicated by _STA), so for those machines,
174 * we want to check _STA before evaluating _SUN.
175 */
176 {
177 .callback = do_sta_before_sun,
178 .ident = "Fujitsu PRIMEQUEST",
179 .matches = {
180 DMI_MATCH(DMI_BIOS_VENDOR, "FUJITSU LIMITED"),
181 DMI_MATCH(DMI_BIOS_VERSION, "PRIMEQUEST"),
182 },
183 },
184 {}
185};
186
187void __init acpi_pci_slot_init(void)
188{
189 dmi_check_system(acpi_pci_slot_dmi_table);
190}