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11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/interrupt.h>
14#include <linux/of.h>
15#include <linux/slab.h>
16#include <linux/sysfs.h>
17#include <linux/fs.h>
18#include <linux/vmalloc.h>
19#include <linux/fcntl.h>
20#include <linux/kobject.h>
21#include <asm/uaccess.h>
22#include <asm/opal.h>
23
24struct elog_obj {
25 struct kobject kobj;
26 struct bin_attribute raw_attr;
27 uint64_t id;
28 uint64_t type;
29 size_t size;
30 char *buffer;
31};
32#define to_elog_obj(x) container_of(x, struct elog_obj, kobj)
33
34struct elog_attribute {
35 struct attribute attr;
36 ssize_t (*show)(struct elog_obj *elog, struct elog_attribute *attr,
37 char *buf);
38 ssize_t (*store)(struct elog_obj *elog, struct elog_attribute *attr,
39 const char *buf, size_t count);
40};
41#define to_elog_attr(x) container_of(x, struct elog_attribute, attr)
42
43static ssize_t elog_id_show(struct elog_obj *elog_obj,
44 struct elog_attribute *attr,
45 char *buf)
46{
47 return sprintf(buf, "0x%llx\n", elog_obj->id);
48}
49
50static const char *elog_type_to_string(uint64_t type)
51{
52 switch (type) {
53 case 0: return "PEL";
54 default: return "unknown";
55 }
56}
57
58static ssize_t elog_type_show(struct elog_obj *elog_obj,
59 struct elog_attribute *attr,
60 char *buf)
61{
62 return sprintf(buf, "0x%llx %s\n",
63 elog_obj->type,
64 elog_type_to_string(elog_obj->type));
65}
66
67static ssize_t elog_ack_show(struct elog_obj *elog_obj,
68 struct elog_attribute *attr,
69 char *buf)
70{
71 return sprintf(buf, "ack - acknowledge log message\n");
72}
73
74static ssize_t elog_ack_store(struct elog_obj *elog_obj,
75 struct elog_attribute *attr,
76 const char *buf,
77 size_t count)
78{
79 opal_send_ack_elog(elog_obj->id);
80 sysfs_remove_file_self(&elog_obj->kobj, &attr->attr);
81 kobject_put(&elog_obj->kobj);
82 return count;
83}
84
85static struct elog_attribute id_attribute =
86 __ATTR(id, S_IRUGO, elog_id_show, NULL);
87static struct elog_attribute type_attribute =
88 __ATTR(type, S_IRUGO, elog_type_show, NULL);
89static struct elog_attribute ack_attribute =
90 __ATTR(acknowledge, 0660, elog_ack_show, elog_ack_store);
91
92static struct kset *elog_kset;
93
94static ssize_t elog_attr_show(struct kobject *kobj,
95 struct attribute *attr,
96 char *buf)
97{
98 struct elog_attribute *attribute;
99 struct elog_obj *elog;
100
101 attribute = to_elog_attr(attr);
102 elog = to_elog_obj(kobj);
103
104 if (!attribute->show)
105 return -EIO;
106
107 return attribute->show(elog, attribute, buf);
108}
109
110static ssize_t elog_attr_store(struct kobject *kobj,
111 struct attribute *attr,
112 const char *buf, size_t len)
113{
114 struct elog_attribute *attribute;
115 struct elog_obj *elog;
116
117 attribute = to_elog_attr(attr);
118 elog = to_elog_obj(kobj);
119
120 if (!attribute->store)
121 return -EIO;
122
123 return attribute->store(elog, attribute, buf, len);
124}
125
126static const struct sysfs_ops elog_sysfs_ops = {
127 .show = elog_attr_show,
128 .store = elog_attr_store,
129};
130
131static void elog_release(struct kobject *kobj)
132{
133 struct elog_obj *elog;
134
135 elog = to_elog_obj(kobj);
136 kfree(elog->buffer);
137 kfree(elog);
138}
139
140static struct attribute *elog_default_attrs[] = {
141 &id_attribute.attr,
142 &type_attribute.attr,
143 &ack_attribute.attr,
144 NULL,
145};
146
147static struct kobj_type elog_ktype = {
148 .sysfs_ops = &elog_sysfs_ops,
149 .release = &elog_release,
150 .default_attrs = elog_default_attrs,
151};
152
153
154#define OPAL_MAX_ERRLOG_SIZE 16384
155
156static ssize_t raw_attr_read(struct file *filep, struct kobject *kobj,
157 struct bin_attribute *bin_attr,
158 char *buffer, loff_t pos, size_t count)
159{
160 int opal_rc;
161
162 struct elog_obj *elog = to_elog_obj(kobj);
163
164
165 if (!elog->buffer) {
166 elog->buffer = kzalloc(elog->size, GFP_KERNEL);
167 if (!elog->buffer)
168 return -EIO;
169
170 opal_rc = opal_read_elog(__pa(elog->buffer),
171 elog->size, elog->id);
172 if (opal_rc != OPAL_SUCCESS) {
173 pr_err("ELOG: log read failed for log-id=%llx\n",
174 elog->id);
175 kfree(elog->buffer);
176 elog->buffer = NULL;
177 return -EIO;
178 }
179 }
180
181 memcpy(buffer, elog->buffer + pos, count);
182
183 return count;
184}
185
186static struct elog_obj *create_elog_obj(uint64_t id, size_t size, uint64_t type)
187{
188 struct elog_obj *elog;
189 int rc;
190
191 elog = kzalloc(sizeof(*elog), GFP_KERNEL);
192 if (!elog)
193 return NULL;
194
195 elog->kobj.kset = elog_kset;
196
197 kobject_init(&elog->kobj, &elog_ktype);
198
199 sysfs_bin_attr_init(&elog->raw_attr);
200
201 elog->raw_attr.attr.name = "raw";
202 elog->raw_attr.attr.mode = 0400;
203 elog->raw_attr.size = size;
204 elog->raw_attr.read = raw_attr_read;
205
206 elog->id = id;
207 elog->size = size;
208 elog->type = type;
209
210 elog->buffer = kzalloc(elog->size, GFP_KERNEL);
211
212 if (elog->buffer) {
213 rc = opal_read_elog(__pa(elog->buffer),
214 elog->size, elog->id);
215 if (rc != OPAL_SUCCESS) {
216 pr_err("ELOG: log read failed for log-id=%llx\n",
217 elog->id);
218 kfree(elog->buffer);
219 elog->buffer = NULL;
220 }
221 }
222
223 rc = kobject_add(&elog->kobj, NULL, "0x%llx", id);
224 if (rc) {
225 kobject_put(&elog->kobj);
226 return NULL;
227 }
228
229 rc = sysfs_create_bin_file(&elog->kobj, &elog->raw_attr);
230 if (rc) {
231 kobject_put(&elog->kobj);
232 return NULL;
233 }
234
235 kobject_uevent(&elog->kobj, KOBJ_ADD);
236
237 return elog;
238}
239
240static irqreturn_t elog_event(int irq, void *data)
241{
242 __be64 size;
243 __be64 id;
244 __be64 type;
245 uint64_t elog_size;
246 uint64_t log_id;
247 uint64_t elog_type;
248 int rc;
249 char name[2+16+1];
250
251 rc = opal_get_elog_size(&id, &size, &type);
252 if (rc != OPAL_SUCCESS) {
253 pr_err("ELOG: OPAL log info read failed\n");
254 return IRQ_HANDLED;
255 }
256
257 elog_size = be64_to_cpu(size);
258 log_id = be64_to_cpu(id);
259 elog_type = be64_to_cpu(type);
260
261 WARN_ON(elog_size > OPAL_MAX_ERRLOG_SIZE);
262
263 if (elog_size >= OPAL_MAX_ERRLOG_SIZE)
264 elog_size = OPAL_MAX_ERRLOG_SIZE;
265
266 sprintf(name, "0x%llx", log_id);
267
268
269
270
271
272 if (kset_find_obj(elog_kset, name))
273 return IRQ_HANDLED;
274
275 create_elog_obj(log_id, elog_size, elog_type);
276
277 return IRQ_HANDLED;
278}
279
280int __init opal_elog_init(void)
281{
282 int rc = 0, irq;
283
284
285 if (!opal_check_token(OPAL_ELOG_READ))
286 return -1;
287
288 elog_kset = kset_create_and_add("elog", NULL, opal_kobj);
289 if (!elog_kset) {
290 pr_warn("%s: failed to create elog kset\n", __func__);
291 return -1;
292 }
293
294 irq = opal_event_request(ilog2(OPAL_EVENT_ERROR_LOG_AVAIL));
295 if (!irq) {
296 pr_err("%s: Can't register OPAL event irq (%d)\n",
297 __func__, irq);
298 return irq;
299 }
300
301 rc = request_threaded_irq(irq, NULL, elog_event,
302 IRQF_TRIGGER_HIGH | IRQF_ONESHOT, "opal-elog", NULL);
303 if (rc) {
304 pr_err("%s: Can't request OPAL event irq (%d)\n",
305 __func__, rc);
306 return rc;
307 }
308
309
310 if (opal_check_token(OPAL_ELOG_RESEND))
311 opal_resend_pending_logs();
312
313 return 0;
314}
315
