1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * EDAC PCI component
4 *
5 * Author: Dave Jiang <djiang@mvista.com>
6 *
7 * 2007 (c) MontaVista Software, Inc.
8 */
9 #include <asm/page.h>
10 #include <linux/uaccess.h>
11 #include <linux/ctype.h>
12 #include <linux/highmem.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/smp.h>
17 #include <linux/spinlock.h>
18 #include <linux/sysctl.h>
19 #include <linux/timer.h>
20
21 #include "edac_pci.h"
22 #include "edac_module.h"
23
24 static DEFINE_MUTEX(edac_pci_ctls_mutex);
25 static LIST_HEAD(edac_pci_list);
26 static atomic_t pci_indexes = ATOMIC_INIT(0);
27
edac_pci_alloc_ctl_info(unsigned int sz_pvt,const char * edac_pci_name)28 struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt,
29 const char *edac_pci_name)
30 {
31 struct edac_pci_ctl_info *pci;
32
33 edac_dbg(1, "\n");
34
35 pci = kzalloc(sizeof(struct edac_pci_ctl_info), GFP_KERNEL);
36 if (!pci)
37 return NULL;
38
39 if (sz_pvt) {
40 pci->pvt_info = kzalloc(sz_pvt, GFP_KERNEL);
41 if (!pci->pvt_info)
42 goto free;
43 }
44
45 pci->op_state = OP_ALLOC;
46
47 snprintf(pci->name, strlen(edac_pci_name) + 1, "%s", edac_pci_name);
48
49 return pci;
50
51 free:
52 kfree(pci);
53 return NULL;
54 }
55 EXPORT_SYMBOL_GPL(edac_pci_alloc_ctl_info);
56
edac_pci_free_ctl_info(struct edac_pci_ctl_info * pci)57 void edac_pci_free_ctl_info(struct edac_pci_ctl_info *pci)
58 {
59 edac_dbg(1, "\n");
60
61 edac_pci_remove_sysfs(pci);
62 }
63 EXPORT_SYMBOL_GPL(edac_pci_free_ctl_info);
64
65 /*
66 * find_edac_pci_by_dev()
67 * scans the edac_pci list for a specific 'struct device *'
68 *
69 * return NULL if not found, or return control struct pointer
70 */
find_edac_pci_by_dev(struct device * dev)71 static struct edac_pci_ctl_info *find_edac_pci_by_dev(struct device *dev)
72 {
73 struct edac_pci_ctl_info *pci;
74 struct list_head *item;
75
76 edac_dbg(1, "\n");
77
78 list_for_each(item, &edac_pci_list) {
79 pci = list_entry(item, struct edac_pci_ctl_info, link);
80
81 if (pci->dev == dev)
82 return pci;
83 }
84
85 return NULL;
86 }
87
88 /*
89 * add_edac_pci_to_global_list
90 * Before calling this function, caller must assign a unique value to
91 * edac_dev->pci_idx.
92 * Return:
93 * 0 on success
94 * 1 on failure
95 */
add_edac_pci_to_global_list(struct edac_pci_ctl_info * pci)96 static int add_edac_pci_to_global_list(struct edac_pci_ctl_info *pci)
97 {
98 struct list_head *item, *insert_before;
99 struct edac_pci_ctl_info *rover;
100
101 edac_dbg(1, "\n");
102
103 insert_before = &edac_pci_list;
104
105 /* Determine if already on the list */
106 rover = find_edac_pci_by_dev(pci->dev);
107 if (unlikely(rover != NULL))
108 goto fail0;
109
110 /* Insert in ascending order by 'pci_idx', so find position */
111 list_for_each(item, &edac_pci_list) {
112 rover = list_entry(item, struct edac_pci_ctl_info, link);
113
114 if (rover->pci_idx >= pci->pci_idx) {
115 if (unlikely(rover->pci_idx == pci->pci_idx))
116 goto fail1;
117
118 insert_before = item;
119 break;
120 }
121 }
122
123 list_add_tail_rcu(&pci->link, insert_before);
124 return 0;
125
126 fail0:
127 edac_printk(KERN_WARNING, EDAC_PCI,
128 "%s (%s) %s %s already assigned %d\n",
129 dev_name(rover->dev), edac_dev_name(rover),
130 rover->mod_name, rover->ctl_name, rover->pci_idx);
131 return 1;
132
133 fail1:
134 edac_printk(KERN_WARNING, EDAC_PCI,
135 "but in low-level driver: attempt to assign\n"
136 "\tduplicate pci_idx %d in %s()\n", rover->pci_idx,
137 __func__);
138 return 1;
139 }
140
141 /*
142 * del_edac_pci_from_global_list
143 *
144 * remove the PCI control struct from the global list
145 */
del_edac_pci_from_global_list(struct edac_pci_ctl_info * pci)146 static void del_edac_pci_from_global_list(struct edac_pci_ctl_info *pci)
147 {
148 list_del_rcu(&pci->link);
149
150 /* these are for safe removal of devices from global list while
151 * NMI handlers may be traversing list
152 */
153 synchronize_rcu();
154 INIT_LIST_HEAD(&pci->link);
155 }
156
157 /*
158 * edac_pci_workq_function()
159 *
160 * periodic function that performs the operation
161 * scheduled by a workq request, for a given PCI control struct
162 */
edac_pci_workq_function(struct work_struct * work_req)163 static void edac_pci_workq_function(struct work_struct *work_req)
164 {
165 struct delayed_work *d_work = to_delayed_work(work_req);
166 struct edac_pci_ctl_info *pci = to_edac_pci_ctl_work(d_work);
167 int msec;
168 unsigned long delay;
169
170 edac_dbg(3, "checking\n");
171
172 mutex_lock(&edac_pci_ctls_mutex);
173
174 if (pci->op_state != OP_RUNNING_POLL) {
175 mutex_unlock(&edac_pci_ctls_mutex);
176 return;
177 }
178
179 if (edac_pci_get_check_errors())
180 pci->edac_check(pci);
181
182 /* if we are on a one second period, then use round */
183 msec = edac_pci_get_poll_msec();
184 if (msec == 1000)
185 delay = round_jiffies_relative(msecs_to_jiffies(msec));
186 else
187 delay = msecs_to_jiffies(msec);
188
189 edac_queue_work(&pci->work, delay);
190
191 mutex_unlock(&edac_pci_ctls_mutex);
192 }
193
edac_pci_alloc_index(void)194 int edac_pci_alloc_index(void)
195 {
196 return atomic_inc_return(&pci_indexes) - 1;
197 }
198 EXPORT_SYMBOL_GPL(edac_pci_alloc_index);
199
edac_pci_add_device(struct edac_pci_ctl_info * pci,int edac_idx)200 int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
201 {
202 edac_dbg(0, "\n");
203
204 pci->pci_idx = edac_idx;
205 pci->start_time = jiffies;
206
207 mutex_lock(&edac_pci_ctls_mutex);
208
209 if (add_edac_pci_to_global_list(pci))
210 goto fail0;
211
212 if (edac_pci_create_sysfs(pci)) {
213 edac_pci_printk(pci, KERN_WARNING,
214 "failed to create sysfs pci\n");
215 goto fail1;
216 }
217
218 if (pci->edac_check) {
219 pci->op_state = OP_RUNNING_POLL;
220
221 INIT_DELAYED_WORK(&pci->work, edac_pci_workq_function);
222 edac_queue_work(&pci->work, msecs_to_jiffies(edac_pci_get_poll_msec()));
223
224 } else {
225 pci->op_state = OP_RUNNING_INTERRUPT;
226 }
227
228 edac_pci_printk(pci, KERN_INFO,
229 "Giving out device to module %s controller %s: DEV %s (%s)\n",
230 pci->mod_name, pci->ctl_name, pci->dev_name,
231 edac_op_state_to_string(pci->op_state));
232
233 mutex_unlock(&edac_pci_ctls_mutex);
234 return 0;
235
236 /* error unwind stack */
237 fail1:
238 del_edac_pci_from_global_list(pci);
239 fail0:
240 mutex_unlock(&edac_pci_ctls_mutex);
241 return 1;
242 }
243 EXPORT_SYMBOL_GPL(edac_pci_add_device);
244
edac_pci_del_device(struct device * dev)245 struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev)
246 {
247 struct edac_pci_ctl_info *pci;
248
249 edac_dbg(0, "\n");
250
251 mutex_lock(&edac_pci_ctls_mutex);
252
253 /* ensure the control struct is on the global list
254 * if not, then leave
255 */
256 pci = find_edac_pci_by_dev(dev);
257 if (pci == NULL) {
258 mutex_unlock(&edac_pci_ctls_mutex);
259 return NULL;
260 }
261
262 pci->op_state = OP_OFFLINE;
263
264 del_edac_pci_from_global_list(pci);
265
266 mutex_unlock(&edac_pci_ctls_mutex);
267
268 if (pci->edac_check)
269 edac_stop_work(&pci->work);
270
271 edac_printk(KERN_INFO, EDAC_PCI,
272 "Removed device %d for %s %s: DEV %s\n",
273 pci->pci_idx, pci->mod_name, pci->ctl_name, edac_dev_name(pci));
274
275 return pci;
276 }
277 EXPORT_SYMBOL_GPL(edac_pci_del_device);
278
279 /*
280 * edac_pci_generic_check
281 *
282 * a Generic parity check API
283 */
edac_pci_generic_check(struct edac_pci_ctl_info * pci)284 static void edac_pci_generic_check(struct edac_pci_ctl_info *pci)
285 {
286 edac_dbg(4, "\n");
287 edac_pci_do_parity_check();
288 }
289
290 /* free running instance index counter */
291 static int edac_pci_idx;
292 #define EDAC_PCI_GENCTL_NAME "EDAC PCI controller"
293
294 struct edac_pci_gen_data {
295 int edac_idx;
296 };
297
edac_pci_create_generic_ctl(struct device * dev,const char * mod_name)298 struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev,
299 const char *mod_name)
300 {
301 struct edac_pci_ctl_info *pci;
302 struct edac_pci_gen_data *pdata;
303
304 pci = edac_pci_alloc_ctl_info(sizeof(*pdata), EDAC_PCI_GENCTL_NAME);
305 if (!pci)
306 return NULL;
307
308 pdata = pci->pvt_info;
309 pci->dev = dev;
310 dev_set_drvdata(pci->dev, pci);
311 pci->dev_name = pci_name(to_pci_dev(dev));
312
313 pci->mod_name = mod_name;
314 pci->ctl_name = EDAC_PCI_GENCTL_NAME;
315 if (edac_op_state == EDAC_OPSTATE_POLL)
316 pci->edac_check = edac_pci_generic_check;
317
318 pdata->edac_idx = edac_pci_idx++;
319
320 if (edac_pci_add_device(pci, pdata->edac_idx) > 0) {
321 edac_dbg(3, "failed edac_pci_add_device()\n");
322 edac_pci_free_ctl_info(pci);
323 return NULL;
324 }
325
326 return pci;
327 }
328 EXPORT_SYMBOL_GPL(edac_pci_create_generic_ctl);
329
edac_pci_release_generic_ctl(struct edac_pci_ctl_info * pci)330 void edac_pci_release_generic_ctl(struct edac_pci_ctl_info *pci)
331 {
332 edac_dbg(0, "pci mod=%s\n", pci->mod_name);
333
334 edac_pci_del_device(pci->dev);
335 edac_pci_free_ctl_info(pci);
336 }
337 EXPORT_SYMBOL_GPL(edac_pci_release_generic_ctl);
338