1 /*
2 * A simple MCE injection facility for testing the MCE decoding code. This
3 * driver should be built as module so that it can be loaded on production
4 * kernels for testing purposes.
5 *
6 * This file may be distributed under the terms of the GNU General Public
7 * License version 2.
8 *
9 * Copyright (c) 2010: Borislav Petkov <borislav.petkov@amd.com>
10 * Advanced Micro Devices Inc.
11 */
12
13 #include <linux/kobject.h>
14 #include <linux/device.h>
15 #include <linux/edac.h>
16 #include <linux/module.h>
17 #include <asm/mce.h>
18
19 #include "mce_amd.h"
20
21 struct edac_mce_attr {
22 struct attribute attr;
23 ssize_t (*show) (struct kobject *kobj, struct edac_mce_attr *attr, char *buf);
24 ssize_t (*store)(struct kobject *kobj, struct edac_mce_attr *attr,
25 const char *buf, size_t count);
26 };
27
28 #define EDAC_MCE_ATTR(_name, _mode, _show, _store) \
29 static struct edac_mce_attr mce_attr_##_name = __ATTR(_name, _mode, _show, _store)
30
31 static struct kobject *mce_kobj;
32
33 /*
34 * Collect all the MCi_XXX settings
35 */
36 static struct mce i_mce;
37
38 #define MCE_INJECT_STORE(reg) \
39 static ssize_t edac_inject_##reg##_store(struct kobject *kobj, \
40 struct edac_mce_attr *attr, \
41 const char *data, size_t count)\
42 { \
43 int ret = 0; \
44 unsigned long value; \
45 \
46 ret = strict_strtoul(data, 16, &value); \
47 if (ret < 0) \
48 printk(KERN_ERR "Error writing MCE " #reg " field.\n"); \
49 \
50 i_mce.reg = value; \
51 \
52 return count; \
53 }
54
55 MCE_INJECT_STORE(status);
56 MCE_INJECT_STORE(misc);
57 MCE_INJECT_STORE(addr);
58
59 #define MCE_INJECT_SHOW(reg) \
60 static ssize_t edac_inject_##reg##_show(struct kobject *kobj, \
61 struct edac_mce_attr *attr, \
62 char *buf) \
63 { \
64 return sprintf(buf, "0x%016llx\n", i_mce.reg); \
65 }
66
67 MCE_INJECT_SHOW(status);
68 MCE_INJECT_SHOW(misc);
69 MCE_INJECT_SHOW(addr);
70
71 EDAC_MCE_ATTR(status, 0644, edac_inject_status_show, edac_inject_status_store);
72 EDAC_MCE_ATTR(misc, 0644, edac_inject_misc_show, edac_inject_misc_store);
73 EDAC_MCE_ATTR(addr, 0644, edac_inject_addr_show, edac_inject_addr_store);
74
75 /*
76 * This denotes into which bank we're injecting and triggers
77 * the injection, at the same time.
78 */
edac_inject_bank_store(struct kobject * kobj,struct edac_mce_attr * attr,const char * data,size_t count)79 static ssize_t edac_inject_bank_store(struct kobject *kobj,
80 struct edac_mce_attr *attr,
81 const char *data, size_t count)
82 {
83 int ret = 0;
84 unsigned long value;
85
86 ret = strict_strtoul(data, 10, &value);
87 if (ret < 0) {
88 printk(KERN_ERR "Invalid bank value!\n");
89 return -EINVAL;
90 }
91
92 if (value > 5)
93 if (boot_cpu_data.x86 != 0x15 || value > 6) {
94 printk(KERN_ERR "Non-existent MCE bank: %lu\n", value);
95 return -EINVAL;
96 }
97
98 i_mce.bank = value;
99
100 amd_decode_mce(NULL, 0, &i_mce);
101
102 return count;
103 }
104
edac_inject_bank_show(struct kobject * kobj,struct edac_mce_attr * attr,char * buf)105 static ssize_t edac_inject_bank_show(struct kobject *kobj,
106 struct edac_mce_attr *attr, char *buf)
107 {
108 return sprintf(buf, "%d\n", i_mce.bank);
109 }
110
111 EDAC_MCE_ATTR(bank, 0644, edac_inject_bank_show, edac_inject_bank_store);
112
113 static struct edac_mce_attr *sysfs_attrs[] = { &mce_attr_status, &mce_attr_misc,
114 &mce_attr_addr, &mce_attr_bank
115 };
116
edac_init_mce_inject(void)117 static int __init edac_init_mce_inject(void)
118 {
119 struct bus_type *edac_subsys = NULL;
120 int i, err = 0;
121
122 edac_subsys = edac_get_sysfs_subsys();
123 if (!edac_subsys)
124 return -EINVAL;
125
126 mce_kobj = kobject_create_and_add("mce", &edac_subsys->dev_root->kobj);
127 if (!mce_kobj) {
128 printk(KERN_ERR "Error creating a mce kset.\n");
129 err = -ENOMEM;
130 goto err_mce_kobj;
131 }
132
133 for (i = 0; i < ARRAY_SIZE(sysfs_attrs); i++) {
134 err = sysfs_create_file(mce_kobj, &sysfs_attrs[i]->attr);
135 if (err) {
136 printk(KERN_ERR "Error creating %s in sysfs.\n",
137 sysfs_attrs[i]->attr.name);
138 goto err_sysfs_create;
139 }
140 }
141 return 0;
142
143 err_sysfs_create:
144 while (--i >= 0)
145 sysfs_remove_file(mce_kobj, &sysfs_attrs[i]->attr);
146
147 kobject_del(mce_kobj);
148
149 err_mce_kobj:
150 edac_put_sysfs_subsys();
151
152 return err;
153 }
154
edac_exit_mce_inject(void)155 static void __exit edac_exit_mce_inject(void)
156 {
157 int i;
158
159 for (i = 0; i < ARRAY_SIZE(sysfs_attrs); i++)
160 sysfs_remove_file(mce_kobj, &sysfs_attrs[i]->attr);
161
162 kobject_del(mce_kobj);
163
164 edac_put_sysfs_subsys();
165 }
166
167 module_init(edac_init_mce_inject);
168 module_exit(edac_exit_mce_inject);
169
170 MODULE_LICENSE("GPL");
171 MODULE_AUTHOR("Borislav Petkov <borislav.petkov@amd.com>");
172 MODULE_AUTHOR("AMD Inc.");
173 MODULE_DESCRIPTION("MCE injection facility for testing MCE decoding");
174