xref: /openbmc/linux/arch/powerpc/kernel/rtasd.c (revision a09d2831)
1 /*
2  * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  *
9  * Communication to userspace based on kernel/printk.c
10  */
11 
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
16 #include <linux/poll.h>
17 #include <linux/proc_fs.h>
18 #include <linux/init.h>
19 #include <linux/vmalloc.h>
20 #include <linux/spinlock.h>
21 #include <linux/cpu.h>
22 #include <linux/workqueue.h>
23 
24 #include <asm/uaccess.h>
25 #include <asm/io.h>
26 #include <asm/rtas.h>
27 #include <asm/prom.h>
28 #include <asm/nvram.h>
29 #include <asm/atomic.h>
30 #include <asm/machdep.h>
31 
32 
33 static DEFINE_SPINLOCK(rtasd_log_lock);
34 
35 static DECLARE_WAIT_QUEUE_HEAD(rtas_log_wait);
36 
37 static char *rtas_log_buf;
38 static unsigned long rtas_log_start;
39 static unsigned long rtas_log_size;
40 
41 static int surveillance_timeout = -1;
42 
43 static unsigned int rtas_error_log_max;
44 static unsigned int rtas_error_log_buffer_max;
45 
46 /* RTAS service tokens */
47 static unsigned int event_scan;
48 static unsigned int rtas_event_scan_rate;
49 
50 static int full_rtas_msgs = 0;
51 
52 /* Stop logging to nvram after first fatal error */
53 static int logging_enabled; /* Until we initialize everything,
54                              * make sure we don't try logging
55                              * anything */
56 static int error_log_cnt;
57 
58 /*
59  * Since we use 32 bit RTAS, the physical address of this must be below
60  * 4G or else bad things happen. Allocate this in the kernel data and
61  * make it big enough.
62  */
63 static unsigned char logdata[RTAS_ERROR_LOG_MAX];
64 
65 static char *rtas_type[] = {
66 	"Unknown", "Retry", "TCE Error", "Internal Device Failure",
67 	"Timeout", "Data Parity", "Address Parity", "Cache Parity",
68 	"Address Invalid", "ECC Uncorrected", "ECC Corrupted",
69 };
70 
71 static char *rtas_event_type(int type)
72 {
73 	if ((type > 0) && (type < 11))
74 		return rtas_type[type];
75 
76 	switch (type) {
77 		case RTAS_TYPE_EPOW:
78 			return "EPOW";
79 		case RTAS_TYPE_PLATFORM:
80 			return "Platform Error";
81 		case RTAS_TYPE_IO:
82 			return "I/O Event";
83 		case RTAS_TYPE_INFO:
84 			return "Platform Information Event";
85 		case RTAS_TYPE_DEALLOC:
86 			return "Resource Deallocation Event";
87 		case RTAS_TYPE_DUMP:
88 			return "Dump Notification Event";
89 	}
90 
91 	return rtas_type[0];
92 }
93 
94 /* To see this info, grep RTAS /var/log/messages and each entry
95  * will be collected together with obvious begin/end.
96  * There will be a unique identifier on the begin and end lines.
97  * This will persist across reboots.
98  *
99  * format of error logs returned from RTAS:
100  * bytes	(size)	: contents
101  * --------------------------------------------------------
102  * 0-7		(8)	: rtas_error_log
103  * 8-47		(40)	: extended info
104  * 48-51	(4)	: vendor id
105  * 52-1023 (vendor specific) : location code and debug data
106  */
107 static void printk_log_rtas(char *buf, int len)
108 {
109 
110 	int i,j,n = 0;
111 	int perline = 16;
112 	char buffer[64];
113 	char * str = "RTAS event";
114 
115 	if (full_rtas_msgs) {
116 		printk(RTAS_DEBUG "%d -------- %s begin --------\n",
117 		       error_log_cnt, str);
118 
119 		/*
120 		 * Print perline bytes on each line, each line will start
121 		 * with RTAS and a changing number, so syslogd will
122 		 * print lines that are otherwise the same.  Separate every
123 		 * 4 bytes with a space.
124 		 */
125 		for (i = 0; i < len; i++) {
126 			j = i % perline;
127 			if (j == 0) {
128 				memset(buffer, 0, sizeof(buffer));
129 				n = sprintf(buffer, "RTAS %d:", i/perline);
130 			}
131 
132 			if ((i % 4) == 0)
133 				n += sprintf(buffer+n, " ");
134 
135 			n += sprintf(buffer+n, "%02x", (unsigned char)buf[i]);
136 
137 			if (j == (perline-1))
138 				printk(KERN_DEBUG "%s\n", buffer);
139 		}
140 		if ((i % perline) != 0)
141 			printk(KERN_DEBUG "%s\n", buffer);
142 
143 		printk(RTAS_DEBUG "%d -------- %s end ----------\n",
144 		       error_log_cnt, str);
145 	} else {
146 		struct rtas_error_log *errlog = (struct rtas_error_log *)buf;
147 
148 		printk(RTAS_DEBUG "event: %d, Type: %s, Severity: %d\n",
149 		       error_log_cnt, rtas_event_type(errlog->type),
150 		       errlog->severity);
151 	}
152 }
153 
154 static int log_rtas_len(char * buf)
155 {
156 	int len;
157 	struct rtas_error_log *err;
158 
159 	/* rtas fixed header */
160 	len = 8;
161 	err = (struct rtas_error_log *)buf;
162 	if (err->extended_log_length) {
163 
164 		/* extended header */
165 		len += err->extended_log_length;
166 	}
167 
168 	if (rtas_error_log_max == 0)
169 		rtas_error_log_max = rtas_get_error_log_max();
170 
171 	if (len > rtas_error_log_max)
172 		len = rtas_error_log_max;
173 
174 	return len;
175 }
176 
177 /*
178  * First write to nvram, if fatal error, that is the only
179  * place we log the info.  The error will be picked up
180  * on the next reboot by rtasd.  If not fatal, run the
181  * method for the type of error.  Currently, only RTAS
182  * errors have methods implemented, but in the future
183  * there might be a need to store data in nvram before a
184  * call to panic().
185  *
186  * XXX We write to nvram periodically, to indicate error has
187  * been written and sync'd, but there is a possibility
188  * that if we don't shutdown correctly, a duplicate error
189  * record will be created on next reboot.
190  */
191 void pSeries_log_error(char *buf, unsigned int err_type, int fatal)
192 {
193 	unsigned long offset;
194 	unsigned long s;
195 	int len = 0;
196 
197 	pr_debug("rtasd: logging event\n");
198 	if (buf == NULL)
199 		return;
200 
201 	spin_lock_irqsave(&rtasd_log_lock, s);
202 
203 	/* get length and increase count */
204 	switch (err_type & ERR_TYPE_MASK) {
205 	case ERR_TYPE_RTAS_LOG:
206 		len = log_rtas_len(buf);
207 		if (!(err_type & ERR_FLAG_BOOT))
208 			error_log_cnt++;
209 		break;
210 	case ERR_TYPE_KERNEL_PANIC:
211 	default:
212 		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
213 		spin_unlock_irqrestore(&rtasd_log_lock, s);
214 		return;
215 	}
216 
217 #ifdef CONFIG_PPC64
218 	/* Write error to NVRAM */
219 	if (logging_enabled && !(err_type & ERR_FLAG_BOOT))
220 		nvram_write_error_log(buf, len, err_type, error_log_cnt);
221 #endif /* CONFIG_PPC64 */
222 
223 	/*
224 	 * rtas errors can occur during boot, and we do want to capture
225 	 * those somewhere, even if nvram isn't ready (why not?), and even
226 	 * if rtasd isn't ready. Put them into the boot log, at least.
227 	 */
228 	if ((err_type & ERR_TYPE_MASK) == ERR_TYPE_RTAS_LOG)
229 		printk_log_rtas(buf, len);
230 
231 	/* Check to see if we need to or have stopped logging */
232 	if (fatal || !logging_enabled) {
233 		logging_enabled = 0;
234 		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
235 		spin_unlock_irqrestore(&rtasd_log_lock, s);
236 		return;
237 	}
238 
239 	/* call type specific method for error */
240 	switch (err_type & ERR_TYPE_MASK) {
241 	case ERR_TYPE_RTAS_LOG:
242 		offset = rtas_error_log_buffer_max *
243 			((rtas_log_start+rtas_log_size) & LOG_NUMBER_MASK);
244 
245 		/* First copy over sequence number */
246 		memcpy(&rtas_log_buf[offset], (void *) &error_log_cnt, sizeof(int));
247 
248 		/* Second copy over error log data */
249 		offset += sizeof(int);
250 		memcpy(&rtas_log_buf[offset], buf, len);
251 
252 		if (rtas_log_size < LOG_NUMBER)
253 			rtas_log_size += 1;
254 		else
255 			rtas_log_start += 1;
256 
257 		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
258 		spin_unlock_irqrestore(&rtasd_log_lock, s);
259 		wake_up_interruptible(&rtas_log_wait);
260 		break;
261 	case ERR_TYPE_KERNEL_PANIC:
262 	default:
263 		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
264 		spin_unlock_irqrestore(&rtasd_log_lock, s);
265 		return;
266 	}
267 
268 }
269 
270 static int rtas_log_open(struct inode * inode, struct file * file)
271 {
272 	return 0;
273 }
274 
275 static int rtas_log_release(struct inode * inode, struct file * file)
276 {
277 	return 0;
278 }
279 
280 /* This will check if all events are logged, if they are then, we
281  * know that we can safely clear the events in NVRAM.
282  * Next we'll sit and wait for something else to log.
283  */
284 static ssize_t rtas_log_read(struct file * file, char __user * buf,
285 			 size_t count, loff_t *ppos)
286 {
287 	int error;
288 	char *tmp;
289 	unsigned long s;
290 	unsigned long offset;
291 
292 	if (!buf || count < rtas_error_log_buffer_max)
293 		return -EINVAL;
294 
295 	count = rtas_error_log_buffer_max;
296 
297 	if (!access_ok(VERIFY_WRITE, buf, count))
298 		return -EFAULT;
299 
300 	tmp = kmalloc(count, GFP_KERNEL);
301 	if (!tmp)
302 		return -ENOMEM;
303 
304 	spin_lock_irqsave(&rtasd_log_lock, s);
305 
306 	/* if it's 0, then we know we got the last one (the one in NVRAM) */
307 	while (rtas_log_size == 0) {
308 		if (file->f_flags & O_NONBLOCK) {
309 			spin_unlock_irqrestore(&rtasd_log_lock, s);
310 			error = -EAGAIN;
311 			goto out;
312 		}
313 
314 		if (!logging_enabled) {
315 			spin_unlock_irqrestore(&rtasd_log_lock, s);
316 			error = -ENODATA;
317 			goto out;
318 		}
319 #ifdef CONFIG_PPC64
320 		nvram_clear_error_log();
321 #endif /* CONFIG_PPC64 */
322 
323 		spin_unlock_irqrestore(&rtasd_log_lock, s);
324 		error = wait_event_interruptible(rtas_log_wait, rtas_log_size);
325 		if (error)
326 			goto out;
327 		spin_lock_irqsave(&rtasd_log_lock, s);
328 	}
329 
330 	offset = rtas_error_log_buffer_max * (rtas_log_start & LOG_NUMBER_MASK);
331 	memcpy(tmp, &rtas_log_buf[offset], count);
332 
333 	rtas_log_start += 1;
334 	rtas_log_size -= 1;
335 	spin_unlock_irqrestore(&rtasd_log_lock, s);
336 
337 	error = copy_to_user(buf, tmp, count) ? -EFAULT : count;
338 out:
339 	kfree(tmp);
340 	return error;
341 }
342 
343 static unsigned int rtas_log_poll(struct file *file, poll_table * wait)
344 {
345 	poll_wait(file, &rtas_log_wait, wait);
346 	if (rtas_log_size)
347 		return POLLIN | POLLRDNORM;
348 	return 0;
349 }
350 
351 static const struct file_operations proc_rtas_log_operations = {
352 	.read =		rtas_log_read,
353 	.poll =		rtas_log_poll,
354 	.open =		rtas_log_open,
355 	.release =	rtas_log_release,
356 };
357 
358 static int enable_surveillance(int timeout)
359 {
360 	int error;
361 
362 	error = rtas_set_indicator(SURVEILLANCE_TOKEN, 0, timeout);
363 
364 	if (error == 0)
365 		return 0;
366 
367 	if (error == -EINVAL) {
368 		printk(KERN_DEBUG "rtasd: surveillance not supported\n");
369 		return 0;
370 	}
371 
372 	printk(KERN_ERR "rtasd: could not update surveillance\n");
373 	return -1;
374 }
375 
376 static void do_event_scan(void)
377 {
378 	int error;
379 	do {
380 		memset(logdata, 0, rtas_error_log_max);
381 		error = rtas_call(event_scan, 4, 1, NULL,
382 				  RTAS_EVENT_SCAN_ALL_EVENTS, 0,
383 				  __pa(logdata), rtas_error_log_max);
384 		if (error == -1) {
385 			printk(KERN_ERR "event-scan failed\n");
386 			break;
387 		}
388 
389 		if (error == 0)
390 			pSeries_log_error(logdata, ERR_TYPE_RTAS_LOG, 0);
391 
392 	} while(error == 0);
393 }
394 
395 static void rtas_event_scan(struct work_struct *w);
396 DECLARE_DELAYED_WORK(event_scan_work, rtas_event_scan);
397 
398 /*
399  * Delay should be at least one second since some machines have problems if
400  * we call event-scan too quickly.
401  */
402 static unsigned long event_scan_delay = 1*HZ;
403 static int first_pass = 1;
404 
405 static void rtas_event_scan(struct work_struct *w)
406 {
407 	unsigned int cpu;
408 
409 	do_event_scan();
410 
411 	get_online_cpus();
412 
413 	cpu = next_cpu(smp_processor_id(), cpu_online_map);
414 	if (cpu == NR_CPUS) {
415 		cpu = first_cpu(cpu_online_map);
416 
417 		if (first_pass) {
418 			first_pass = 0;
419 			event_scan_delay = 30*HZ/rtas_event_scan_rate;
420 
421 			if (surveillance_timeout != -1) {
422 				pr_debug("rtasd: enabling surveillance\n");
423 				enable_surveillance(surveillance_timeout);
424 				pr_debug("rtasd: surveillance enabled\n");
425 			}
426 		}
427 	}
428 
429 	schedule_delayed_work_on(cpu, &event_scan_work,
430 		__round_jiffies_relative(event_scan_delay, cpu));
431 
432 	put_online_cpus();
433 }
434 
435 #ifdef CONFIG_PPC64
436 static void retreive_nvram_error_log(void)
437 {
438 	unsigned int err_type ;
439 	int rc ;
440 
441 	/* See if we have any error stored in NVRAM */
442 	memset(logdata, 0, rtas_error_log_max);
443 	rc = nvram_read_error_log(logdata, rtas_error_log_max,
444 	                          &err_type, &error_log_cnt);
445 	/* We can use rtas_log_buf now */
446 	logging_enabled = 1;
447 	if (!rc) {
448 		if (err_type != ERR_FLAG_ALREADY_LOGGED) {
449 			pSeries_log_error(logdata, err_type | ERR_FLAG_BOOT, 0);
450 		}
451 	}
452 }
453 #else /* CONFIG_PPC64 */
454 static void retreive_nvram_error_log(void)
455 {
456 }
457 #endif /* CONFIG_PPC64 */
458 
459 static void start_event_scan(void)
460 {
461 	printk(KERN_DEBUG "RTAS daemon started\n");
462 	pr_debug("rtasd: will sleep for %d milliseconds\n",
463 		 (30000 / rtas_event_scan_rate));
464 
465 	/* Retreive errors from nvram if any */
466 	retreive_nvram_error_log();
467 
468 	schedule_delayed_work_on(first_cpu(cpu_online_map), &event_scan_work,
469 				 event_scan_delay);
470 }
471 
472 static int __init rtas_init(void)
473 {
474 	struct proc_dir_entry *entry;
475 
476 	if (!machine_is(pseries) && !machine_is(chrp))
477 		return 0;
478 
479 	/* No RTAS */
480 	event_scan = rtas_token("event-scan");
481 	if (event_scan == RTAS_UNKNOWN_SERVICE) {
482 		printk(KERN_INFO "rtasd: No event-scan on system\n");
483 		return -ENODEV;
484 	}
485 
486 	rtas_event_scan_rate = rtas_token("rtas-event-scan-rate");
487 	if (rtas_event_scan_rate == RTAS_UNKNOWN_SERVICE) {
488 		printk(KERN_ERR "rtasd: no rtas-event-scan-rate on system\n");
489 		return -ENODEV;
490 	}
491 
492 	/* Make room for the sequence number */
493 	rtas_error_log_max = rtas_get_error_log_max();
494 	rtas_error_log_buffer_max = rtas_error_log_max + sizeof(int);
495 
496 	rtas_log_buf = vmalloc(rtas_error_log_buffer_max*LOG_NUMBER);
497 	if (!rtas_log_buf) {
498 		printk(KERN_ERR "rtasd: no memory\n");
499 		return -ENOMEM;
500 	}
501 
502 	entry = proc_create("powerpc/rtas/error_log", S_IRUSR, NULL,
503 			    &proc_rtas_log_operations);
504 	if (!entry)
505 		printk(KERN_ERR "Failed to create error_log proc entry\n");
506 
507 	start_event_scan();
508 
509 	return 0;
510 }
511 __initcall(rtas_init);
512 
513 static int __init surveillance_setup(char *str)
514 {
515 	int i;
516 
517 	/* We only do surveillance on pseries */
518 	if (!machine_is(pseries))
519 		return 0;
520 
521 	if (get_option(&str,&i)) {
522 		if (i >= 0 && i <= 255)
523 			surveillance_timeout = i;
524 	}
525 
526 	return 1;
527 }
528 __setup("surveillance=", surveillance_setup);
529 
530 static int __init rtasmsgs_setup(char *str)
531 {
532 	if (strcmp(str, "on") == 0)
533 		full_rtas_msgs = 1;
534 	else if (strcmp(str, "off") == 0)
535 		full_rtas_msgs = 0;
536 
537 	return 1;
538 }
539 __setup("rtasmsgs=", rtasmsgs_setup);
540