summaryrefslogtreecommitdiffstats
path: root/drivers/edac/edac_pci.c
blob: 48c844a72a278bc13e72e0af0674b53f3fe06e04 (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
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
/*
 * EDAC PCI component
 *
 * Author: Dave Jiang <djiang@mvista.com>
 *
 * 2007 (c) MontaVista Software, Inc. This file is licensed under
 * the terms of the GNU General Public License version 2. This program
 * is licensed "as is" without any warranty of any kind, whether express
 * or implied.
 *
 */
#include <asm/page.h>
#include <linux/uaccess.h>
#include <linux/ctype.h>
#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/sysctl.h>
#include <linux/timer.h>

#include "edac_pci.h"
#include "edac_module.h"

static DEFINE_MUTEX(edac_pci_ctls_mutex);
static LIST_HEAD(edac_pci_list);
static atomic_t pci_indexes = ATOMIC_INIT(0);

struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt,
						const char *edac_pci_name)
{
	struct edac_pci_ctl_info *pci;
	void *p = NULL, *pvt;
	unsigned int size;

	edac_dbg(1, "\n");

	pci = edac_align_ptr(&p, sizeof(*pci), 1);
	pvt = edac_align_ptr(&p, 1, sz_pvt);
	size = ((unsigned long)pvt) + sz_pvt;

	/* Alloc the needed control struct memory */
	pci = kzalloc(size, GFP_KERNEL);
	if (pci  == NULL)
		return NULL;

	/* Now much private space */
	pvt = sz_pvt ? ((char *)pci) + ((unsigned long)pvt) : NULL;

	pci->pvt_info = pvt;
	pci->op_state = OP_ALLOC;

	snprintf(pci->name, strlen(edac_pci_name) + 1, "%s", edac_pci_name);

	return pci;
}
EXPORT_SYMBOL_GPL(edac_pci_alloc_ctl_info);

void edac_pci_free_ctl_info(struct edac_pci_ctl_info *pci)
{
	edac_dbg(1, "\n");

	edac_pci_remove_sysfs(pci);
}
EXPORT_SYMBOL_GPL(edac_pci_free_ctl_info);

/*
 * find_edac_pci_by_dev()
 * 	scans the edac_pci list for a specific 'struct device *'
 *
 *	return NULL if not found, or return control struct pointer
 */
static struct edac_pci_ctl_info *find_edac_pci_by_dev(struct device *dev)
{
	struct edac_pci_ctl_info *pci;
	struct list_head *item;

	edac_dbg(1, "\n");

	list_for_each(item, &edac_pci_list) {
		pci = list_entry(item, struct edac_pci_ctl_info, link);

		if (pci->dev == dev)
			return pci;
	}

	return NULL;
}

/*
 * add_edac_pci_to_global_list
 * 	Before calling this function, caller must assign a unique value to
 * 	edac_dev->pci_idx.
 * 	Return:
 * 		0 on success
 * 		1 on failure
 */
static int add_edac_pci_to_global_list(struct edac_pci_ctl_info *pci)
{
	struct list_head *item, *insert_before;
	struct edac_pci_ctl_info *rover;

	edac_dbg(1, "\n");

	insert_before = &edac_pci_list;

	/* Determine if already on the list */
	rover = find_edac_pci_by_dev(pci->dev);
	if (unlikely(rover != NULL))
		goto fail0;

	/* Insert in ascending order by 'pci_idx', so find position */
	list_for_each(item, &edac_pci_list) {
		rover = list_entry(item, struct edac_pci_ctl_info, link);

		if (rover->pci_idx >= pci->pci_idx) {
			if (unlikely(rover->pci_idx == pci->pci_idx))
				goto fail1;

			insert_before = item;
			break;
		}
	}

	list_add_tail_rcu(&pci->link, insert_before);
	return 0;

fail0:
	edac_printk(KERN_WARNING, EDAC_PCI,
		"%s (%s) %s %s already assigned %d\n",
		dev_name(rover->dev), edac_dev_name(rover),
		rover->mod_name, rover->ctl_name, rover->pci_idx);
	return 1;

fail1:
	edac_printk(KERN_WARNING, EDAC_PCI,
		"but in low-level driver: attempt to assign\n"
		"\tduplicate pci_idx %d in %s()\n", rover->pci_idx,
		__func__);
	return 1;
}

/*
 * del_edac_pci_from_global_list
 *
 *	remove the PCI control struct from the global list
 */
static void del_edac_pci_from_global_list(struct edac_pci_ctl_info *pci)
{
	list_del_rcu(&pci->link);

	/* these are for safe removal of devices from global list while
	 * NMI handlers may be traversing list
	 */
	synchronize_rcu();
	INIT_LIST_HEAD(&pci->link);
}

/*
 * edac_pci_workq_function()
 *
 * 	periodic function that performs the operation
 *	scheduled by a workq request, for a given PCI control struct
 */
static void edac_pci_workq_function(struct work_struct *work_req)
{
	struct delayed_work *d_work = to_delayed_work(work_req);
	struct edac_pci_ctl_info *pci = to_edac_pci_ctl_work(d_work);
	int msec;
	unsigned long delay;

	edac_dbg(3, "checking\n");

	mutex_lock(&edac_pci_ctls_mutex);

	if (pci->op_state != OP_RUNNING_POLL) {
		mutex_unlock(&edac_pci_ctls_mutex);
		return;
	}

	if (edac_pci_get_check_errors())
		pci->edac_check(pci);

	/* if we are on a one second period, then use round */
	msec = edac_pci_get_poll_msec();
	if (msec == 1000)
		delay = round_jiffies_relative(msecs_to_jiffies(msec));
	else
		delay = msecs_to_jiffies(msec);

	edac_queue_work(&pci->work, delay);

	mutex_unlock(&edac_pci_ctls_mutex);
}

int edac_pci_alloc_index(void)
{
	return atomic_inc_return(&pci_indexes) - 1;
}
EXPORT_SYMBOL_GPL(edac_pci_alloc_index);

int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
{
	edac_dbg(0, "\n");

	pci->pci_idx = edac_idx;
	pci->start_time = jiffies;

	mutex_lock(&edac_pci_ctls_mutex);

	if (add_edac_pci_to_global_list(pci))
		goto fail0;

	if (edac_pci_create_sysfs(pci)) {
		edac_pci_printk(pci, KERN_WARNING,
				"failed to create sysfs pci\n");
		goto fail1;
	}

	if (pci->edac_check) {
		pci->op_state = OP_RUNNING_POLL;

		INIT_DELAYED_WORK(&pci->work, edac_pci_workq_function);
		edac_queue_work(&pci->work, msecs_to_jiffies(edac_pci_get_poll_msec()));

	} else {
		pci->op_state = OP_RUNNING_INTERRUPT;
	}

	edac_pci_printk(pci, KERN_INFO,
		"Giving out device to module %s controller %s: DEV %s (%s)\n",
		pci->mod_name, pci->ctl_name, pci->dev_name,
		edac_op_state_to_string(pci->op_state));

	mutex_unlock(&edac_pci_ctls_mutex);
	return 0;

	/* error unwind stack */
fail1:
	del_edac_pci_from_global_list(pci);
fail0:
	mutex_unlock(&edac_pci_ctls_mutex);
	return 1;
}
EXPORT_SYMBOL_GPL(edac_pci_add_device);

struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev)
{
	struct edac_pci_ctl_info *pci;

	edac_dbg(0, "\n");

	mutex_lock(&edac_pci_ctls_mutex);

	/* ensure the control struct is on the global list
	 * if not, then leave
	 */
	pci = find_edac_pci_by_dev(dev);
	if (pci  == NULL) {
		mutex_unlock(&edac_pci_ctls_mutex);
		return NULL;
	}

	pci->op_state = OP_OFFLINE;

	del_edac_pci_from_global_list(pci);

	mutex_unlock(&edac_pci_ctls_mutex);

	if (pci->edac_check)
		edac_stop_work(&pci->work);

	edac_printk(KERN_INFO, EDAC_PCI,
		"Removed device %d for %s %s: DEV %s\n",
		pci->pci_idx, pci->mod_name, pci->ctl_name, edac_dev_name(pci));

	return pci;
}
EXPORT_SYMBOL_GPL(edac_pci_del_device);

/*
 * edac_pci_generic_check
 *
 *	a Generic parity check API
 */
static void edac_pci_generic_check(struct edac_pci_ctl_info *pci)
{
	edac_dbg(4, "\n");
	edac_pci_do_parity_check();
}

/* free running instance index counter */
static int edac_pci_idx;
#define EDAC_PCI_GENCTL_NAME	"EDAC PCI controller"

struct edac_pci_gen_data {
	int edac_idx;
};

struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev,
						const char *mod_name)
{
	struct edac_pci_ctl_info *pci;
	struct edac_pci_gen_data *pdata;

	pci = edac_pci_alloc_ctl_info(sizeof(*pdata), EDAC_PCI_GENCTL_NAME);
	if (!pci)
		return NULL;

	pdata = pci->pvt_info;
	pci->dev = dev;
	dev_set_drvdata(pci->dev, pci);
	pci->dev_name = pci_name(to_pci_dev(dev));

	pci->mod_name = mod_name;
	pci->ctl_name = EDAC_PCI_GENCTL_NAME;
	if (edac_op_state == EDAC_OPSTATE_POLL)
		pci->edac_check = edac_pci_generic_check;

	pdata->edac_idx = edac_pci_idx++;

	if (edac_pci_add_device(pci, pdata->edac_idx) > 0) {
		edac_dbg(3, "failed edac_pci_add_device()\n");
		edac_pci_free_ctl_info(pci);
		return NULL;
	}

	return pci;
}
EXPORT_SYMBOL_GPL(edac_pci_create_generic_ctl);

void edac_pci_release_generic_ctl(struct edac_pci_ctl_info *pci)
{
	edac_dbg(0, "pci mod=%s\n", pci->mod_name);

	edac_pci_del_device(pci->dev);
	edac_pci_free_ctl_info(pci);
}
EXPORT_SYMBOL_GPL(edac_pci_release_generic_ctl);