xref: /openbmc/linux/arch/ia64/kernel/err_inject.c (revision 195c5ad9)
1 /*
2  * err_inject.c -
3  *	1.) Inject errors to a processor.
4  *	2.) Query error injection capabilities.
5  * This driver along with user space code can be acting as an error
6  * injection tool.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16  * NON INFRINGEMENT.  See the GNU General Public License for more
17  * details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Written by: Fenghua Yu <fenghua.yu@intel.com>, Intel Corporation
24  * Copyright (C) 2006, Intel Corp.  All rights reserved.
25  *
26  */
27 #include <linux/device.h>
28 #include <linux/init.h>
29 #include <linux/mm.h>
30 #include <linux/cpu.h>
31 #include <linux/module.h>
32 
33 #define ERR_INJ_DEBUG
34 
35 #define ERR_DATA_BUFFER_SIZE 3 		// Three 8-byte;
36 
37 #define define_one_ro(name) 						\
38 static DEVICE_ATTR(name, 0444, show_##name, NULL)
39 
40 #define define_one_rw(name) 						\
41 static DEVICE_ATTR(name, 0644, show_##name, store_##name)
42 
43 static u64 call_start[NR_CPUS];
44 static u64 phys_addr[NR_CPUS];
45 static u64 err_type_info[NR_CPUS];
46 static u64 err_struct_info[NR_CPUS];
47 static struct {
48 	u64 data1;
49 	u64 data2;
50 	u64 data3;
51 } __attribute__((__aligned__(16))) err_data_buffer[NR_CPUS];
52 static s64 status[NR_CPUS];
53 static u64 capabilities[NR_CPUS];
54 static u64 resources[NR_CPUS];
55 
56 #define show(name) 							\
57 static ssize_t 								\
58 show_##name(struct device *dev, struct device_attribute *attr,	\
59 		char *buf)						\
60 {									\
61 	u32 cpu=dev->id;						\
62 	return sprintf(buf, "%llx\n", name[cpu]);			\
63 }
64 
65 #define store(name)							\
66 static ssize_t 								\
67 store_##name(struct device *dev, struct device_attribute *attr,	\
68 					const char *buf, size_t size)	\
69 {									\
70 	unsigned int cpu=dev->id;					\
71 	name[cpu] = simple_strtoull(buf, NULL, 16);			\
72 	return size;							\
73 }
74 
75 show(call_start)
76 
77 /* It's user's responsibility to call the PAL procedure on a specific
78  * processor. The cpu number in driver is only used for storing data.
79  */
80 static ssize_t
81 store_call_start(struct device *dev, struct device_attribute *attr,
82 		const char *buf, size_t size)
83 {
84 	unsigned int cpu=dev->id;
85 	unsigned long call_start = simple_strtoull(buf, NULL, 16);
86 
87 #ifdef ERR_INJ_DEBUG
88 	printk(KERN_DEBUG "pal_mc_err_inject for cpu%d:\n", cpu);
89 	printk(KERN_DEBUG "err_type_info=%llx,\n", err_type_info[cpu]);
90 	printk(KERN_DEBUG "err_struct_info=%llx,\n", err_struct_info[cpu]);
91 	printk(KERN_DEBUG "err_data_buffer=%llx, %llx, %llx.\n",
92 			  err_data_buffer[cpu].data1,
93 			  err_data_buffer[cpu].data2,
94 			  err_data_buffer[cpu].data3);
95 #endif
96 	switch (call_start) {
97 	    case 0: /* Do nothing. */
98 		break;
99 	    case 1: /* Call pal_mc_error_inject in physical mode. */
100 		status[cpu]=ia64_pal_mc_error_inject_phys(err_type_info[cpu],
101 					err_struct_info[cpu],
102 					ia64_tpa(&err_data_buffer[cpu]),
103 					&capabilities[cpu],
104 			 		&resources[cpu]);
105 		break;
106 	    case 2: /* Call pal_mc_error_inject in virtual mode. */
107 		status[cpu]=ia64_pal_mc_error_inject_virt(err_type_info[cpu],
108 					err_struct_info[cpu],
109 					ia64_tpa(&err_data_buffer[cpu]),
110 					&capabilities[cpu],
111 			 		&resources[cpu]);
112 		break;
113 	    default:
114 		status[cpu] = -EINVAL;
115 		break;
116 	}
117 
118 #ifdef ERR_INJ_DEBUG
119 	printk(KERN_DEBUG "Returns: status=%d,\n", (int)status[cpu]);
120 	printk(KERN_DEBUG "capabilities=%llx,\n", capabilities[cpu]);
121 	printk(KERN_DEBUG "resources=%llx\n", resources[cpu]);
122 #endif
123 	return size;
124 }
125 
126 show(err_type_info)
127 store(err_type_info)
128 
129 static ssize_t
130 show_virtual_to_phys(struct device *dev, struct device_attribute *attr,
131 			char *buf)
132 {
133 	unsigned int cpu=dev->id;
134 	return sprintf(buf, "%llx\n", phys_addr[cpu]);
135 }
136 
137 static ssize_t
138 store_virtual_to_phys(struct device *dev, struct device_attribute *attr,
139 			const char *buf, size_t size)
140 {
141 	unsigned int cpu=dev->id;
142 	u64 virt_addr=simple_strtoull(buf, NULL, 16);
143 	int ret;
144 
145 	ret = get_user_pages_fast(virt_addr, 1, FOLL_WRITE, NULL);
146 	if (ret<=0) {
147 #ifdef ERR_INJ_DEBUG
148 		printk("Virtual address %llx is not existing.\n", virt_addr);
149 #endif
150 		return -EINVAL;
151 	}
152 
153 	phys_addr[cpu] = ia64_tpa(virt_addr);
154 	return size;
155 }
156 
157 show(err_struct_info)
158 store(err_struct_info)
159 
160 static ssize_t
161 show_err_data_buffer(struct device *dev,
162 			struct device_attribute *attr, char *buf)
163 {
164 	unsigned int cpu=dev->id;
165 
166 	return sprintf(buf, "%llx, %llx, %llx\n",
167 			err_data_buffer[cpu].data1,
168 			err_data_buffer[cpu].data2,
169 			err_data_buffer[cpu].data3);
170 }
171 
172 static ssize_t
173 store_err_data_buffer(struct device *dev,
174 			struct device_attribute *attr,
175 			const char *buf, size_t size)
176 {
177 	unsigned int cpu=dev->id;
178 	int ret;
179 
180 #ifdef ERR_INJ_DEBUG
181 	printk("write err_data_buffer=[%llx,%llx,%llx] on cpu%d\n",
182 		 err_data_buffer[cpu].data1,
183 		 err_data_buffer[cpu].data2,
184 		 err_data_buffer[cpu].data3,
185 		 cpu);
186 #endif
187 	ret = sscanf(buf, "%llx, %llx, %llx",
188 			&err_data_buffer[cpu].data1,
189 			&err_data_buffer[cpu].data2,
190 			&err_data_buffer[cpu].data3);
191 	if (ret!=ERR_DATA_BUFFER_SIZE)
192 		return -EINVAL;
193 
194 	return size;
195 }
196 
197 show(status)
198 show(capabilities)
199 show(resources)
200 
201 define_one_rw(call_start);
202 define_one_rw(err_type_info);
203 define_one_rw(err_struct_info);
204 define_one_rw(err_data_buffer);
205 define_one_rw(virtual_to_phys);
206 define_one_ro(status);
207 define_one_ro(capabilities);
208 define_one_ro(resources);
209 
210 static struct attribute *default_attrs[] = {
211 	&dev_attr_call_start.attr,
212 	&dev_attr_virtual_to_phys.attr,
213 	&dev_attr_err_type_info.attr,
214 	&dev_attr_err_struct_info.attr,
215 	&dev_attr_err_data_buffer.attr,
216 	&dev_attr_status.attr,
217 	&dev_attr_capabilities.attr,
218 	&dev_attr_resources.attr,
219 	NULL
220 };
221 
222 static struct attribute_group err_inject_attr_group = {
223 	.attrs = default_attrs,
224 	.name = "err_inject"
225 };
226 /* Add/Remove err_inject interface for CPU device */
227 static int err_inject_add_dev(unsigned int cpu)
228 {
229 	struct device *sys_dev = get_cpu_device(cpu);
230 
231 	return sysfs_create_group(&sys_dev->kobj, &err_inject_attr_group);
232 }
233 
234 static int err_inject_remove_dev(unsigned int cpu)
235 {
236 	struct device *sys_dev = get_cpu_device(cpu);
237 
238 	sysfs_remove_group(&sys_dev->kobj, &err_inject_attr_group);
239 	return 0;
240 }
241 
242 static enum cpuhp_state hp_online;
243 
244 static int __init err_inject_init(void)
245 {
246 	int ret;
247 #ifdef ERR_INJ_DEBUG
248 	printk(KERN_INFO "Enter error injection driver.\n");
249 #endif
250 
251 	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "ia64/err_inj:online",
252 				err_inject_add_dev, err_inject_remove_dev);
253 	if (ret >= 0) {
254 		hp_online = ret;
255 		ret = 0;
256 	}
257 	return ret;
258 }
259 
260 static void __exit err_inject_exit(void)
261 {
262 #ifdef ERR_INJ_DEBUG
263 	printk(KERN_INFO "Exit error injection driver.\n");
264 #endif
265 	cpuhp_remove_state(hp_online);
266 }
267 
268 module_init(err_inject_init);
269 module_exit(err_inject_exit);
270 
271 MODULE_AUTHOR("Fenghua Yu <fenghua.yu@intel.com>");
272 MODULE_DESCRIPTION("MC error injection kernel sysfs interface");
273 MODULE_LICENSE("GPL");
274