xref: /openbmc/linux/drivers/acpi/apei/einj.c (revision 565d76cb)
1 /*
2  * APEI Error INJection support
3  *
4  * EINJ provides a hardware error injection mechanism, this is useful
5  * for debugging and testing of other APEI and RAS features.
6  *
7  * For more information about EINJ, please refer to ACPI Specification
8  * version 4.0, section 17.5.
9  *
10  * Copyright 2009-2010 Intel Corp.
11  *   Author: Huang Ying <ying.huang@intel.com>
12  *
13  * This program is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License version
15  * 2 as published by the Free Software Foundation.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
25  */
26 
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/io.h>
31 #include <linux/debugfs.h>
32 #include <linux/seq_file.h>
33 #include <linux/nmi.h>
34 #include <linux/delay.h>
35 #include <acpi/acpi.h>
36 
37 #include "apei-internal.h"
38 
39 #define EINJ_PFX "EINJ: "
40 
41 #define SPIN_UNIT		100			/* 100ns */
42 /* Firmware should respond within 1 milliseconds */
43 #define FIRMWARE_TIMEOUT	(1 * NSEC_PER_MSEC)
44 
45 /*
46  * Some BIOSes allow parameters to the SET_ERROR_TYPE entries in the
47  * EINJ table through an unpublished extension. Use with caution as
48  * most will ignore the parameter and make their own choice of address
49  * for error injection.
50  */
51 struct einj_parameter {
52 	u64 type;
53 	u64 reserved1;
54 	u64 reserved2;
55 	u64 param1;
56 	u64 param2;
57 };
58 
59 #define EINJ_OP_BUSY			0x1
60 #define EINJ_STATUS_SUCCESS		0x0
61 #define EINJ_STATUS_FAIL		0x1
62 #define EINJ_STATUS_INVAL		0x2
63 
64 #define EINJ_TAB_ENTRY(tab)						\
65 	((struct acpi_whea_header *)((char *)(tab) +			\
66 				    sizeof(struct acpi_table_einj)))
67 
68 static struct acpi_table_einj *einj_tab;
69 
70 static struct apei_resources einj_resources;
71 
72 static struct apei_exec_ins_type einj_ins_type[] = {
73 	[ACPI_EINJ_READ_REGISTER] = {
74 		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
75 		.run   = apei_exec_read_register,
76 	},
77 	[ACPI_EINJ_READ_REGISTER_VALUE] = {
78 		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
79 		.run   = apei_exec_read_register_value,
80 	},
81 	[ACPI_EINJ_WRITE_REGISTER] = {
82 		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
83 		.run   = apei_exec_write_register,
84 	},
85 	[ACPI_EINJ_WRITE_REGISTER_VALUE] = {
86 		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
87 		.run   = apei_exec_write_register_value,
88 	},
89 	[ACPI_EINJ_NOOP] = {
90 		.flags = 0,
91 		.run   = apei_exec_noop,
92 	},
93 };
94 
95 /*
96  * Prevent EINJ interpreter to run simultaneously, because the
97  * corresponding firmware implementation may not work properly when
98  * invoked simultaneously.
99  */
100 static DEFINE_MUTEX(einj_mutex);
101 
102 static struct einj_parameter *einj_param;
103 
104 static void einj_exec_ctx_init(struct apei_exec_context *ctx)
105 {
106 	apei_exec_ctx_init(ctx, einj_ins_type, ARRAY_SIZE(einj_ins_type),
107 			   EINJ_TAB_ENTRY(einj_tab), einj_tab->entries);
108 }
109 
110 static int __einj_get_available_error_type(u32 *type)
111 {
112 	struct apei_exec_context ctx;
113 	int rc;
114 
115 	einj_exec_ctx_init(&ctx);
116 	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_ERROR_TYPE);
117 	if (rc)
118 		return rc;
119 	*type = apei_exec_ctx_get_output(&ctx);
120 
121 	return 0;
122 }
123 
124 /* Get error injection capabilities of the platform */
125 static int einj_get_available_error_type(u32 *type)
126 {
127 	int rc;
128 
129 	mutex_lock(&einj_mutex);
130 	rc = __einj_get_available_error_type(type);
131 	mutex_unlock(&einj_mutex);
132 
133 	return rc;
134 }
135 
136 static int einj_timedout(u64 *t)
137 {
138 	if ((s64)*t < SPIN_UNIT) {
139 		pr_warning(FW_WARN EINJ_PFX
140 			   "Firmware does not respond in time\n");
141 		return 1;
142 	}
143 	*t -= SPIN_UNIT;
144 	ndelay(SPIN_UNIT);
145 	touch_nmi_watchdog();
146 	return 0;
147 }
148 
149 static u64 einj_get_parameter_address(void)
150 {
151 	int i;
152 	u64 paddr = 0;
153 	struct acpi_whea_header *entry;
154 
155 	entry = EINJ_TAB_ENTRY(einj_tab);
156 	for (i = 0; i < einj_tab->entries; i++) {
157 		if (entry->action == ACPI_EINJ_SET_ERROR_TYPE &&
158 		    entry->instruction == ACPI_EINJ_WRITE_REGISTER &&
159 		    entry->register_region.space_id ==
160 		    ACPI_ADR_SPACE_SYSTEM_MEMORY)
161 			memcpy(&paddr, &entry->register_region.address,
162 			       sizeof(paddr));
163 		entry++;
164 	}
165 
166 	return paddr;
167 }
168 
169 /* do sanity check to trigger table */
170 static int einj_check_trigger_header(struct acpi_einj_trigger *trigger_tab)
171 {
172 	if (trigger_tab->header_size != sizeof(struct acpi_einj_trigger))
173 		return -EINVAL;
174 	if (trigger_tab->table_size > PAGE_SIZE ||
175 	    trigger_tab->table_size <= trigger_tab->header_size)
176 		return -EINVAL;
177 	if (trigger_tab->entry_count !=
178 	    (trigger_tab->table_size - trigger_tab->header_size) /
179 	    sizeof(struct acpi_einj_entry))
180 		return -EINVAL;
181 
182 	return 0;
183 }
184 
185 /* Execute instructions in trigger error action table */
186 static int __einj_error_trigger(u64 trigger_paddr)
187 {
188 	struct acpi_einj_trigger *trigger_tab = NULL;
189 	struct apei_exec_context trigger_ctx;
190 	struct apei_resources trigger_resources;
191 	struct acpi_whea_header *trigger_entry;
192 	struct resource *r;
193 	u32 table_size;
194 	int rc = -EIO;
195 
196 	r = request_mem_region(trigger_paddr, sizeof(*trigger_tab),
197 			       "APEI EINJ Trigger Table");
198 	if (!r) {
199 		pr_err(EINJ_PFX
200 	"Can not request iomem region <%016llx-%016llx> for Trigger table.\n",
201 		       (unsigned long long)trigger_paddr,
202 		       (unsigned long long)trigger_paddr+sizeof(*trigger_tab));
203 		goto out;
204 	}
205 	trigger_tab = ioremap_cache(trigger_paddr, sizeof(*trigger_tab));
206 	if (!trigger_tab) {
207 		pr_err(EINJ_PFX "Failed to map trigger table!\n");
208 		goto out_rel_header;
209 	}
210 	rc = einj_check_trigger_header(trigger_tab);
211 	if (rc) {
212 		pr_warning(FW_BUG EINJ_PFX
213 			   "The trigger error action table is invalid\n");
214 		goto out_rel_header;
215 	}
216 	rc = -EIO;
217 	table_size = trigger_tab->table_size;
218 	r = request_mem_region(trigger_paddr + sizeof(*trigger_tab),
219 			       table_size - sizeof(*trigger_tab),
220 			       "APEI EINJ Trigger Table");
221 	if (!r) {
222 		pr_err(EINJ_PFX
223 "Can not request iomem region <%016llx-%016llx> for Trigger Table Entry.\n",
224 		       (unsigned long long)trigger_paddr+sizeof(*trigger_tab),
225 		       (unsigned long long)trigger_paddr + table_size);
226 		goto out_rel_header;
227 	}
228 	iounmap(trigger_tab);
229 	trigger_tab = ioremap_cache(trigger_paddr, table_size);
230 	if (!trigger_tab) {
231 		pr_err(EINJ_PFX "Failed to map trigger table!\n");
232 		goto out_rel_entry;
233 	}
234 	trigger_entry = (struct acpi_whea_header *)
235 		((char *)trigger_tab + sizeof(struct acpi_einj_trigger));
236 	apei_resources_init(&trigger_resources);
237 	apei_exec_ctx_init(&trigger_ctx, einj_ins_type,
238 			   ARRAY_SIZE(einj_ins_type),
239 			   trigger_entry, trigger_tab->entry_count);
240 	rc = apei_exec_collect_resources(&trigger_ctx, &trigger_resources);
241 	if (rc)
242 		goto out_fini;
243 	rc = apei_resources_sub(&trigger_resources, &einj_resources);
244 	if (rc)
245 		goto out_fini;
246 	rc = apei_resources_request(&trigger_resources, "APEI EINJ Trigger");
247 	if (rc)
248 		goto out_fini;
249 	rc = apei_exec_pre_map_gars(&trigger_ctx);
250 	if (rc)
251 		goto out_release;
252 
253 	rc = apei_exec_run(&trigger_ctx, ACPI_EINJ_TRIGGER_ERROR);
254 
255 	apei_exec_post_unmap_gars(&trigger_ctx);
256 out_release:
257 	apei_resources_release(&trigger_resources);
258 out_fini:
259 	apei_resources_fini(&trigger_resources);
260 out_rel_entry:
261 	release_mem_region(trigger_paddr + sizeof(*trigger_tab),
262 			   table_size - sizeof(*trigger_tab));
263 out_rel_header:
264 	release_mem_region(trigger_paddr, sizeof(*trigger_tab));
265 out:
266 	if (trigger_tab)
267 		iounmap(trigger_tab);
268 
269 	return rc;
270 }
271 
272 static int __einj_error_inject(u32 type, u64 param1, u64 param2)
273 {
274 	struct apei_exec_context ctx;
275 	u64 val, trigger_paddr, timeout = FIRMWARE_TIMEOUT;
276 	int rc;
277 
278 	einj_exec_ctx_init(&ctx);
279 
280 	rc = apei_exec_run(&ctx, ACPI_EINJ_BEGIN_OPERATION);
281 	if (rc)
282 		return rc;
283 	apei_exec_ctx_set_input(&ctx, type);
284 	rc = apei_exec_run(&ctx, ACPI_EINJ_SET_ERROR_TYPE);
285 	if (rc)
286 		return rc;
287 	if (einj_param) {
288 		writeq(param1, &einj_param->param1);
289 		writeq(param2, &einj_param->param2);
290 	}
291 	rc = apei_exec_run(&ctx, ACPI_EINJ_EXECUTE_OPERATION);
292 	if (rc)
293 		return rc;
294 	for (;;) {
295 		rc = apei_exec_run(&ctx, ACPI_EINJ_CHECK_BUSY_STATUS);
296 		if (rc)
297 			return rc;
298 		val = apei_exec_ctx_get_output(&ctx);
299 		if (!(val & EINJ_OP_BUSY))
300 			break;
301 		if (einj_timedout(&timeout))
302 			return -EIO;
303 	}
304 	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_COMMAND_STATUS);
305 	if (rc)
306 		return rc;
307 	val = apei_exec_ctx_get_output(&ctx);
308 	if (val != EINJ_STATUS_SUCCESS)
309 		return -EBUSY;
310 
311 	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_TRIGGER_TABLE);
312 	if (rc)
313 		return rc;
314 	trigger_paddr = apei_exec_ctx_get_output(&ctx);
315 	rc = __einj_error_trigger(trigger_paddr);
316 	if (rc)
317 		return rc;
318 	rc = apei_exec_run(&ctx, ACPI_EINJ_END_OPERATION);
319 
320 	return rc;
321 }
322 
323 /* Inject the specified hardware error */
324 static int einj_error_inject(u32 type, u64 param1, u64 param2)
325 {
326 	int rc;
327 
328 	mutex_lock(&einj_mutex);
329 	rc = __einj_error_inject(type, param1, param2);
330 	mutex_unlock(&einj_mutex);
331 
332 	return rc;
333 }
334 
335 static u32 error_type;
336 static u64 error_param1;
337 static u64 error_param2;
338 static struct dentry *einj_debug_dir;
339 
340 static int available_error_type_show(struct seq_file *m, void *v)
341 {
342 	int rc;
343 	u32 available_error_type = 0;
344 
345 	rc = einj_get_available_error_type(&available_error_type);
346 	if (rc)
347 		return rc;
348 	if (available_error_type & 0x0001)
349 		seq_printf(m, "0x00000001\tProcessor Correctable\n");
350 	if (available_error_type & 0x0002)
351 		seq_printf(m, "0x00000002\tProcessor Uncorrectable non-fatal\n");
352 	if (available_error_type & 0x0004)
353 		seq_printf(m, "0x00000004\tProcessor Uncorrectable fatal\n");
354 	if (available_error_type & 0x0008)
355 		seq_printf(m, "0x00000008\tMemory Correctable\n");
356 	if (available_error_type & 0x0010)
357 		seq_printf(m, "0x00000010\tMemory Uncorrectable non-fatal\n");
358 	if (available_error_type & 0x0020)
359 		seq_printf(m, "0x00000020\tMemory Uncorrectable fatal\n");
360 	if (available_error_type & 0x0040)
361 		seq_printf(m, "0x00000040\tPCI Express Correctable\n");
362 	if (available_error_type & 0x0080)
363 		seq_printf(m, "0x00000080\tPCI Express Uncorrectable non-fatal\n");
364 	if (available_error_type & 0x0100)
365 		seq_printf(m, "0x00000100\tPCI Express Uncorrectable fatal\n");
366 	if (available_error_type & 0x0200)
367 		seq_printf(m, "0x00000200\tPlatform Correctable\n");
368 	if (available_error_type & 0x0400)
369 		seq_printf(m, "0x00000400\tPlatform Uncorrectable non-fatal\n");
370 	if (available_error_type & 0x0800)
371 		seq_printf(m, "0x00000800\tPlatform Uncorrectable fatal\n");
372 
373 	return 0;
374 }
375 
376 static int available_error_type_open(struct inode *inode, struct file *file)
377 {
378 	return single_open(file, available_error_type_show, NULL);
379 }
380 
381 static const struct file_operations available_error_type_fops = {
382 	.open		= available_error_type_open,
383 	.read		= seq_read,
384 	.llseek		= seq_lseek,
385 	.release	= single_release,
386 };
387 
388 static int error_type_get(void *data, u64 *val)
389 {
390 	*val = error_type;
391 
392 	return 0;
393 }
394 
395 static int error_type_set(void *data, u64 val)
396 {
397 	int rc;
398 	u32 available_error_type = 0;
399 
400 	/* Only one error type can be specified */
401 	if (val & (val - 1))
402 		return -EINVAL;
403 	rc = einj_get_available_error_type(&available_error_type);
404 	if (rc)
405 		return rc;
406 	if (!(val & available_error_type))
407 		return -EINVAL;
408 	error_type = val;
409 
410 	return 0;
411 }
412 
413 DEFINE_SIMPLE_ATTRIBUTE(error_type_fops, error_type_get,
414 			error_type_set, "0x%llx\n");
415 
416 static int error_inject_set(void *data, u64 val)
417 {
418 	if (!error_type)
419 		return -EINVAL;
420 
421 	return einj_error_inject(error_type, error_param1, error_param2);
422 }
423 
424 DEFINE_SIMPLE_ATTRIBUTE(error_inject_fops, NULL,
425 			error_inject_set, "%llu\n");
426 
427 static int einj_check_table(struct acpi_table_einj *einj_tab)
428 {
429 	if ((einj_tab->header_length !=
430 	     (sizeof(struct acpi_table_einj) - sizeof(einj_tab->header)))
431 	    && (einj_tab->header_length != sizeof(struct acpi_table_einj)))
432 		return -EINVAL;
433 	if (einj_tab->header.length < sizeof(struct acpi_table_einj))
434 		return -EINVAL;
435 	if (einj_tab->entries !=
436 	    (einj_tab->header.length - sizeof(struct acpi_table_einj)) /
437 	    sizeof(struct acpi_einj_entry))
438 		return -EINVAL;
439 
440 	return 0;
441 }
442 
443 static int __init einj_init(void)
444 {
445 	int rc;
446 	u64 param_paddr;
447 	acpi_status status;
448 	struct dentry *fentry;
449 	struct apei_exec_context ctx;
450 
451 	if (acpi_disabled)
452 		return -ENODEV;
453 
454 	status = acpi_get_table(ACPI_SIG_EINJ, 0,
455 				(struct acpi_table_header **)&einj_tab);
456 	if (status == AE_NOT_FOUND) {
457 		pr_info(EINJ_PFX "Table is not found!\n");
458 		return -ENODEV;
459 	} else if (ACPI_FAILURE(status)) {
460 		const char *msg = acpi_format_exception(status);
461 		pr_err(EINJ_PFX "Failed to get table, %s\n", msg);
462 		return -EINVAL;
463 	}
464 
465 	rc = einj_check_table(einj_tab);
466 	if (rc) {
467 		pr_warning(FW_BUG EINJ_PFX "EINJ table is invalid\n");
468 		return -EINVAL;
469 	}
470 
471 	rc = -ENOMEM;
472 	einj_debug_dir = debugfs_create_dir("einj", apei_get_debugfs_dir());
473 	if (!einj_debug_dir)
474 		goto err_cleanup;
475 	fentry = debugfs_create_file("available_error_type", S_IRUSR,
476 				     einj_debug_dir, NULL,
477 				     &available_error_type_fops);
478 	if (!fentry)
479 		goto err_cleanup;
480 	fentry = debugfs_create_file("error_type", S_IRUSR | S_IWUSR,
481 				     einj_debug_dir, NULL, &error_type_fops);
482 	if (!fentry)
483 		goto err_cleanup;
484 	fentry = debugfs_create_x64("param1", S_IRUSR | S_IWUSR,
485 				    einj_debug_dir, &error_param1);
486 	if (!fentry)
487 		goto err_cleanup;
488 	fentry = debugfs_create_x64("param2", S_IRUSR | S_IWUSR,
489 				    einj_debug_dir, &error_param2);
490 	if (!fentry)
491 		goto err_cleanup;
492 	fentry = debugfs_create_file("error_inject", S_IWUSR,
493 				     einj_debug_dir, NULL, &error_inject_fops);
494 	if (!fentry)
495 		goto err_cleanup;
496 
497 	apei_resources_init(&einj_resources);
498 	einj_exec_ctx_init(&ctx);
499 	rc = apei_exec_collect_resources(&ctx, &einj_resources);
500 	if (rc)
501 		goto err_fini;
502 	rc = apei_resources_request(&einj_resources, "APEI EINJ");
503 	if (rc)
504 		goto err_fini;
505 	rc = apei_exec_pre_map_gars(&ctx);
506 	if (rc)
507 		goto err_release;
508 	param_paddr = einj_get_parameter_address();
509 	if (param_paddr) {
510 		einj_param = ioremap(param_paddr, sizeof(*einj_param));
511 		rc = -ENOMEM;
512 		if (!einj_param)
513 			goto err_unmap;
514 	}
515 
516 	pr_info(EINJ_PFX "Error INJection is initialized.\n");
517 
518 	return 0;
519 
520 err_unmap:
521 	apei_exec_post_unmap_gars(&ctx);
522 err_release:
523 	apei_resources_release(&einj_resources);
524 err_fini:
525 	apei_resources_fini(&einj_resources);
526 err_cleanup:
527 	debugfs_remove_recursive(einj_debug_dir);
528 
529 	return rc;
530 }
531 
532 static void __exit einj_exit(void)
533 {
534 	struct apei_exec_context ctx;
535 
536 	if (einj_param)
537 		iounmap(einj_param);
538 	einj_exec_ctx_init(&ctx);
539 	apei_exec_post_unmap_gars(&ctx);
540 	apei_resources_release(&einj_resources);
541 	apei_resources_fini(&einj_resources);
542 	debugfs_remove_recursive(einj_debug_dir);
543 }
544 
545 module_init(einj_init);
546 module_exit(einj_exit);
547 
548 MODULE_AUTHOR("Huang Ying");
549 MODULE_DESCRIPTION("APEI Error INJection support");
550 MODULE_LICENSE("GPL");
551