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11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/of.h>
14#include <linux/slab.h>
15#include <linux/sysfs.h>
16#include <linux/fs.h>
17#include <linux/vmalloc.h>
18#include <linux/fcntl.h>
19#include <linux/kobject.h>
20#include <asm/uaccess.h>
21#include <asm/opal.h>
22
23struct elog_obj {
24 struct kobject kobj;
25 struct bin_attribute raw_attr;
26 uint64_t id;
27 uint64_t type;
28 size_t size;
29 char *buffer;
30};
31#define to_elog_obj(x) container_of(x, struct elog_obj, kobj)
32
33struct elog_attribute {
34 struct attribute attr;
35 ssize_t (*show)(struct elog_obj *elog, struct elog_attribute *attr,
36 char *buf);
37 ssize_t (*store)(struct elog_obj *elog, struct elog_attribute *attr,
38 const char *buf, size_t count);
39};
40#define to_elog_attr(x) container_of(x, struct elog_attribute, attr)
41
42static ssize_t elog_id_show(struct elog_obj *elog_obj,
43 struct elog_attribute *attr,
44 char *buf)
45{
46 return sprintf(buf, "0x%llx\n", elog_obj->id);
47}
48
49static const char *elog_type_to_string(uint64_t type)
50{
51 switch (type) {
52 case 0: return "PEL";
53 default: return "unknown";
54 }
55}
56
57static ssize_t elog_type_show(struct elog_obj *elog_obj,
58 struct elog_attribute *attr,
59 char *buf)
60{
61 return sprintf(buf, "0x%llx %s\n",
62 elog_obj->type,
63 elog_type_to_string(elog_obj->type));
64}
65
66static ssize_t elog_ack_show(struct elog_obj *elog_obj,
67 struct elog_attribute *attr,
68 char *buf)
69{
70 return sprintf(buf, "ack - acknowledge log message\n");
71}
72
73static ssize_t elog_ack_store(struct elog_obj *elog_obj,
74 struct elog_attribute *attr,
75 const char *buf,
76 size_t count)
77{
78 opal_send_ack_elog(elog_obj->id);
79 sysfs_remove_file_self(&elog_obj->kobj, &attr->attr);
80 kobject_put(&elog_obj->kobj);
81 return count;
82}
83
84static struct elog_attribute id_attribute =
85 __ATTR(id, S_IRUGO, elog_id_show, NULL);
86static struct elog_attribute type_attribute =
87 __ATTR(type, S_IRUGO, elog_type_show, NULL);
88static struct elog_attribute ack_attribute =
89 __ATTR(acknowledge, 0660, elog_ack_show, elog_ack_store);
90
91static struct kset *elog_kset;
92
93static ssize_t elog_attr_show(struct kobject *kobj,
94 struct attribute *attr,
95 char *buf)
96{
97 struct elog_attribute *attribute;
98 struct elog_obj *elog;
99
100 attribute = to_elog_attr(attr);
101 elog = to_elog_obj(kobj);
102
103 if (!attribute->show)
104 return -EIO;
105
106 return attribute->show(elog, attribute, buf);
107}
108
109static ssize_t elog_attr_store(struct kobject *kobj,
110 struct attribute *attr,
111 const char *buf, size_t len)
112{
113 struct elog_attribute *attribute;
114 struct elog_obj *elog;
115
116 attribute = to_elog_attr(attr);
117 elog = to_elog_obj(kobj);
118
119 if (!attribute->store)
120 return -EIO;
121
122 return attribute->store(elog, attribute, buf, len);
123}
124
125static const struct sysfs_ops elog_sysfs_ops = {
126 .show = elog_attr_show,
127 .store = elog_attr_store,
128};
129
130static void elog_release(struct kobject *kobj)
131{
132 struct elog_obj *elog;
133
134 elog = to_elog_obj(kobj);
135 kfree(elog->buffer);
136 kfree(elog);
137}
138
139static struct attribute *elog_default_attrs[] = {
140 &id_attribute.attr,
141 &type_attribute.attr,
142 &ack_attribute.attr,
143 NULL,
144};
145
146static struct kobj_type elog_ktype = {
147 .sysfs_ops = &elog_sysfs_ops,
148 .release = &elog_release,
149 .default_attrs = elog_default_attrs,
150};
151
152
153#define OPAL_MAX_ERRLOG_SIZE 16384
154
155static ssize_t raw_attr_read(struct file *filep, struct kobject *kobj,
156 struct bin_attribute *bin_attr,
157 char *buffer, loff_t pos, size_t count)
158{
159 int opal_rc;
160
161 struct elog_obj *elog = to_elog_obj(kobj);
162
163
164 if (!elog->buffer) {
165 elog->buffer = kzalloc(elog->size, GFP_KERNEL);
166 if (!elog->buffer)
167 return -EIO;
168
169 opal_rc = opal_read_elog(__pa(elog->buffer),
170 elog->size, elog->id);
171 if (opal_rc != OPAL_SUCCESS) {
172 pr_err("ELOG: log read failed for log-id=%llx\n",
173 elog->id);
174 kfree(elog->buffer);
175 elog->buffer = NULL;
176 return -EIO;
177 }
178 }
179
180 memcpy(buffer, elog->buffer + pos, count);
181
182 return count;
183}
184
185static struct elog_obj *create_elog_obj(uint64_t id, size_t size, uint64_t type)
186{
187 struct elog_obj *elog;
188 int rc;
189
190 elog = kzalloc(sizeof(*elog), GFP_KERNEL);
191 if (!elog)
192 return NULL;
193
194 elog->kobj.kset = elog_kset;
195
196 kobject_init(&elog->kobj, &elog_ktype);
197
198 sysfs_bin_attr_init(&elog->raw_attr);
199
200 elog->raw_attr.attr.name = "raw";
201 elog->raw_attr.attr.mode = 0400;
202 elog->raw_attr.size = size;
203 elog->raw_attr.read = raw_attr_read;
204
205 elog->id = id;
206 elog->size = size;
207 elog->type = type;
208
209 elog->buffer = kzalloc(elog->size, GFP_KERNEL);
210
211 if (elog->buffer) {
212 rc = opal_read_elog(__pa(elog->buffer),
213 elog->size, elog->id);
214 if (rc != OPAL_SUCCESS) {
215 pr_err("ELOG: log read failed for log-id=%llx\n",
216 elog->id);
217 kfree(elog->buffer);
218 elog->buffer = NULL;
219 }
220 }
221
222 rc = kobject_add(&elog->kobj, NULL, "0x%llx", id);
223 if (rc) {
224 kobject_put(&elog->kobj);
225 return NULL;
226 }
227
228 rc = sysfs_create_bin_file(&elog->kobj, &elog->raw_attr);
229 if (rc) {
230 kobject_put(&elog->kobj);
231 return NULL;
232 }
233
234 kobject_uevent(&elog->kobj, KOBJ_ADD);
235
236 return elog;
237}
238
239static void elog_work_fn(struct work_struct *work)
240{
241 __be64 size;
242 __be64 id;
243 __be64 type;
244 uint64_t elog_size;
245 uint64_t log_id;
246 uint64_t elog_type;
247 int rc;
248 char name[2+16+1];
249
250 rc = opal_get_elog_size(&id, &size, &type);
251 if (rc != OPAL_SUCCESS) {
252 pr_err("ELOG: OPAL log info read failed\n");
253 return;
254 }
255
256 elog_size = be64_to_cpu(size);
257 log_id = be64_to_cpu(id);
258 elog_type = be64_to_cpu(type);
259
260 WARN_ON(elog_size > OPAL_MAX_ERRLOG_SIZE);
261
262 if (elog_size >= OPAL_MAX_ERRLOG_SIZE)
263 elog_size = OPAL_MAX_ERRLOG_SIZE;
264
265 sprintf(name, "0x%llx", log_id);
266
267
268
269
270
271 if (kset_find_obj(elog_kset, name))
272 return;
273
274 create_elog_obj(log_id, elog_size, elog_type);
275}
276
277static DECLARE_WORK(elog_work, elog_work_fn);
278
279static int elog_event(struct notifier_block *nb,
280 unsigned long events, void *change)
281{
282
283 if (events & OPAL_EVENT_ERROR_LOG_AVAIL)
284 schedule_work(&elog_work);
285 return 0;
286}
287
288static struct notifier_block elog_nb = {
289 .notifier_call = elog_event,
290 .next = NULL,
291 .priority = 0
292};
293
294int __init opal_elog_init(void)
295{
296 int rc = 0;
297
298
299 if (!opal_check_token(OPAL_ELOG_READ))
300 return -1;
301
302 elog_kset = kset_create_and_add("elog", NULL, opal_kobj);
303 if (!elog_kset) {
304 pr_warn("%s: failed to create elog kset\n", __func__);
305 return -1;
306 }
307
308 rc = opal_notifier_register(&elog_nb);
309 if (rc) {
310 pr_err("%s: Can't register OPAL event notifier (%d)\n",
311 __func__, rc);
312 return rc;
313 }
314
315
316 opal_resend_pending_logs();
317
318 return 0;
319}
320
