1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM |
4 | * |
5 | * Communication to userspace based on kernel/printk.c |
6 | */ |
7 | |
8 | #include <linux/types.h> |
9 | #include <linux/errno.h> |
10 | #include <linux/sched.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/of.h> |
13 | #include <linux/poll.h> |
14 | #include <linux/proc_fs.h> |
15 | #include <linux/init.h> |
16 | #include <linux/vmalloc.h> |
17 | #include <linux/spinlock.h> |
18 | #include <linux/cpu.h> |
19 | #include <linux/workqueue.h> |
20 | #include <linux/slab.h> |
21 | #include <linux/topology.h> |
22 | |
23 | #include <linux/uaccess.h> |
24 | #include <asm/io.h> |
25 | #include <asm/rtas.h> |
26 | #include <asm/nvram.h> |
27 | #include <linux/atomic.h> |
28 | #include <asm/machdep.h> |
29 | #include <asm/topology.h> |
30 | |
31 | |
32 | static DEFINE_SPINLOCK(rtasd_log_lock); |
33 | |
34 | static DECLARE_WAIT_QUEUE_HEAD(rtas_log_wait); |
35 | |
36 | static char *rtas_log_buf; |
37 | static unsigned long rtas_log_start; |
38 | static unsigned long rtas_log_size; |
39 | |
40 | static int surveillance_timeout = -1; |
41 | |
42 | static unsigned int rtas_error_log_max; |
43 | static unsigned int rtas_error_log_buffer_max; |
44 | |
45 | /* RTAS service tokens */ |
46 | static unsigned int event_scan; |
47 | static unsigned int rtas_event_scan_rate; |
48 | |
49 | static bool full_rtas_msgs; |
50 | |
51 | /* Stop logging to nvram after first fatal error */ |
52 | static int logging_enabled; /* Until we initialize everything, |
53 | * make sure we don't try logging |
54 | * anything */ |
55 | static int error_log_cnt; |
56 | |
57 | /* |
58 | * Since we use 32 bit RTAS, the physical address of this must be below |
59 | * 4G or else bad things happen. Allocate this in the kernel data and |
60 | * make it big enough. |
61 | */ |
62 | static unsigned char logdata[RTAS_ERROR_LOG_MAX]; |
63 | |
64 | static char *rtas_type[] = { |
65 | "Unknown" , "Retry" , "TCE Error" , "Internal Device Failure" , |
66 | "Timeout" , "Data Parity" , "Address Parity" , "Cache Parity" , |
67 | "Address Invalid" , "ECC Uncorrected" , "ECC Corrupted" , |
68 | }; |
69 | |
70 | static char *rtas_event_type(int type) |
71 | { |
72 | if ((type > 0) && (type < 11)) |
73 | return rtas_type[type]; |
74 | |
75 | switch (type) { |
76 | case RTAS_TYPE_EPOW: |
77 | return "EPOW" ; |
78 | case RTAS_TYPE_PLATFORM: |
79 | return "Platform Error" ; |
80 | case RTAS_TYPE_IO: |
81 | return "I/O Event" ; |
82 | case RTAS_TYPE_INFO: |
83 | return "Platform Information Event" ; |
84 | case RTAS_TYPE_DEALLOC: |
85 | return "Resource Deallocation Event" ; |
86 | case RTAS_TYPE_DUMP: |
87 | return "Dump Notification Event" ; |
88 | case RTAS_TYPE_PRRN: |
89 | return "Platform Resource Reassignment Event" ; |
90 | case RTAS_TYPE_HOTPLUG: |
91 | return "Hotplug Event" ; |
92 | } |
93 | |
94 | return rtas_type[0]; |
95 | } |
96 | |
97 | /* To see this info, grep RTAS /var/log/messages and each entry |
98 | * will be collected together with obvious begin/end. |
99 | * There will be a unique identifier on the begin and end lines. |
100 | * This will persist across reboots. |
101 | * |
102 | * format of error logs returned from RTAS: |
103 | * bytes (size) : contents |
104 | * -------------------------------------------------------- |
105 | * 0-7 (8) : rtas_error_log |
106 | * 8-47 (40) : extended info |
107 | * 48-51 (4) : vendor id |
108 | * 52-1023 (vendor specific) : location code and debug data |
109 | */ |
110 | static void printk_log_rtas(char *buf, int len) |
111 | { |
112 | |
113 | int i,j,n = 0; |
114 | int perline = 16; |
115 | char buffer[64]; |
116 | char * str = "RTAS event" ; |
117 | |
118 | if (full_rtas_msgs) { |
119 | printk(RTAS_DEBUG "%d -------- %s begin --------\n" , |
120 | error_log_cnt, str); |
121 | |
122 | /* |
123 | * Print perline bytes on each line, each line will start |
124 | * with RTAS and a changing number, so syslogd will |
125 | * print lines that are otherwise the same. Separate every |
126 | * 4 bytes with a space. |
127 | */ |
128 | for (i = 0; i < len; i++) { |
129 | j = i % perline; |
130 | if (j == 0) { |
131 | memset(buffer, 0, sizeof(buffer)); |
132 | n = sprintf(buf: buffer, fmt: "RTAS %d:" , i/perline); |
133 | } |
134 | |
135 | if ((i % 4) == 0) |
136 | n += sprintf(buf: buffer+n, fmt: " " ); |
137 | |
138 | n += sprintf(buf: buffer+n, fmt: "%02x" , (unsigned char)buf[i]); |
139 | |
140 | if (j == (perline-1)) |
141 | printk(KERN_DEBUG "%s\n" , buffer); |
142 | } |
143 | if ((i % perline) != 0) |
144 | printk(KERN_DEBUG "%s\n" , buffer); |
145 | |
146 | printk(RTAS_DEBUG "%d -------- %s end ----------\n" , |
147 | error_log_cnt, str); |
148 | } else { |
149 | struct rtas_error_log *errlog = (struct rtas_error_log *)buf; |
150 | |
151 | printk(RTAS_DEBUG "event: %d, Type: %s (%d), Severity: %d\n" , |
152 | error_log_cnt, |
153 | rtas_event_type(rtas_error_type(errlog)), |
154 | rtas_error_type(errlog), |
155 | rtas_error_severity(errlog)); |
156 | } |
157 | } |
158 | |
159 | static int log_rtas_len(char * buf) |
160 | { |
161 | int len; |
162 | struct rtas_error_log *err; |
163 | uint32_t extended_log_length; |
164 | |
165 | /* rtas fixed header */ |
166 | len = 8; |
167 | err = (struct rtas_error_log *)buf; |
168 | extended_log_length = rtas_error_extended_log_length(err); |
169 | if (rtas_error_extended(err) && extended_log_length) { |
170 | |
171 | /* extended header */ |
172 | len += extended_log_length; |
173 | } |
174 | |
175 | if (rtas_error_log_max == 0) |
176 | rtas_error_log_max = rtas_get_error_log_max(); |
177 | |
178 | if (len > rtas_error_log_max) |
179 | len = rtas_error_log_max; |
180 | |
181 | return len; |
182 | } |
183 | |
184 | /* |
185 | * First write to nvram, if fatal error, that is the only |
186 | * place we log the info. The error will be picked up |
187 | * on the next reboot by rtasd. If not fatal, run the |
188 | * method for the type of error. Currently, only RTAS |
189 | * errors have methods implemented, but in the future |
190 | * there might be a need to store data in nvram before a |
191 | * call to panic(). |
192 | * |
193 | * XXX We write to nvram periodically, to indicate error has |
194 | * been written and sync'd, but there is a possibility |
195 | * that if we don't shutdown correctly, a duplicate error |
196 | * record will be created on next reboot. |
197 | */ |
198 | void pSeries_log_error(char *buf, unsigned int err_type, int fatal) |
199 | { |
200 | unsigned long offset; |
201 | unsigned long s; |
202 | int len = 0; |
203 | |
204 | pr_debug("rtasd: logging event\n" ); |
205 | if (buf == NULL) |
206 | return; |
207 | |
208 | spin_lock_irqsave(&rtasd_log_lock, s); |
209 | |
210 | /* get length and increase count */ |
211 | switch (err_type & ERR_TYPE_MASK) { |
212 | case ERR_TYPE_RTAS_LOG: |
213 | len = log_rtas_len(buf); |
214 | if (!(err_type & ERR_FLAG_BOOT)) |
215 | error_log_cnt++; |
216 | break; |
217 | case ERR_TYPE_KERNEL_PANIC: |
218 | default: |
219 | WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */ |
220 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
221 | return; |
222 | } |
223 | |
224 | #ifdef CONFIG_PPC64 |
225 | /* Write error to NVRAM */ |
226 | if (logging_enabled && !(err_type & ERR_FLAG_BOOT)) |
227 | nvram_write_error_log(buf, len, err_type, error_log_cnt); |
228 | #endif /* CONFIG_PPC64 */ |
229 | |
230 | /* |
231 | * rtas errors can occur during boot, and we do want to capture |
232 | * those somewhere, even if nvram isn't ready (why not?), and even |
233 | * if rtasd isn't ready. Put them into the boot log, at least. |
234 | */ |
235 | if ((err_type & ERR_TYPE_MASK) == ERR_TYPE_RTAS_LOG) |
236 | printk_log_rtas(buf, len); |
237 | |
238 | /* Check to see if we need to or have stopped logging */ |
239 | if (fatal || !logging_enabled) { |
240 | logging_enabled = 0; |
241 | WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */ |
242 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
243 | return; |
244 | } |
245 | |
246 | /* call type specific method for error */ |
247 | switch (err_type & ERR_TYPE_MASK) { |
248 | case ERR_TYPE_RTAS_LOG: |
249 | offset = rtas_error_log_buffer_max * |
250 | ((rtas_log_start+rtas_log_size) & LOG_NUMBER_MASK); |
251 | |
252 | /* First copy over sequence number */ |
253 | memcpy(&rtas_log_buf[offset], (void *) &error_log_cnt, sizeof(int)); |
254 | |
255 | /* Second copy over error log data */ |
256 | offset += sizeof(int); |
257 | memcpy(&rtas_log_buf[offset], buf, len); |
258 | |
259 | if (rtas_log_size < LOG_NUMBER) |
260 | rtas_log_size += 1; |
261 | else |
262 | rtas_log_start += 1; |
263 | |
264 | WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */ |
265 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
266 | wake_up_interruptible(&rtas_log_wait); |
267 | break; |
268 | case ERR_TYPE_KERNEL_PANIC: |
269 | default: |
270 | WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */ |
271 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
272 | return; |
273 | } |
274 | } |
275 | |
276 | static void handle_rtas_event(const struct rtas_error_log *log) |
277 | { |
278 | if (!machine_is(pseries)) |
279 | return; |
280 | |
281 | if (rtas_error_type(log) == RTAS_TYPE_PRRN) |
282 | pr_info_ratelimited("Platform resource reassignment ignored.\n" ); |
283 | } |
284 | |
285 | static int rtas_log_open(struct inode * inode, struct file * file) |
286 | { |
287 | return 0; |
288 | } |
289 | |
290 | static int rtas_log_release(struct inode * inode, struct file * file) |
291 | { |
292 | return 0; |
293 | } |
294 | |
295 | /* This will check if all events are logged, if they are then, we |
296 | * know that we can safely clear the events in NVRAM. |
297 | * Next we'll sit and wait for something else to log. |
298 | */ |
299 | static ssize_t rtas_log_read(struct file * file, char __user * buf, |
300 | size_t count, loff_t *ppos) |
301 | { |
302 | int error; |
303 | char *tmp; |
304 | unsigned long s; |
305 | unsigned long offset; |
306 | |
307 | if (!buf || count < rtas_error_log_buffer_max) |
308 | return -EINVAL; |
309 | |
310 | count = rtas_error_log_buffer_max; |
311 | |
312 | if (!access_ok(buf, count)) |
313 | return -EFAULT; |
314 | |
315 | tmp = kmalloc(size: count, GFP_KERNEL); |
316 | if (!tmp) |
317 | return -ENOMEM; |
318 | |
319 | spin_lock_irqsave(&rtasd_log_lock, s); |
320 | |
321 | /* if it's 0, then we know we got the last one (the one in NVRAM) */ |
322 | while (rtas_log_size == 0) { |
323 | if (file->f_flags & O_NONBLOCK) { |
324 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
325 | error = -EAGAIN; |
326 | goto out; |
327 | } |
328 | |
329 | if (!logging_enabled) { |
330 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
331 | error = -ENODATA; |
332 | goto out; |
333 | } |
334 | #ifdef CONFIG_PPC64 |
335 | nvram_clear_error_log(); |
336 | #endif /* CONFIG_PPC64 */ |
337 | |
338 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
339 | error = wait_event_interruptible(rtas_log_wait, rtas_log_size); |
340 | if (error) |
341 | goto out; |
342 | spin_lock_irqsave(&rtasd_log_lock, s); |
343 | } |
344 | |
345 | offset = rtas_error_log_buffer_max * (rtas_log_start & LOG_NUMBER_MASK); |
346 | memcpy(tmp, &rtas_log_buf[offset], count); |
347 | |
348 | rtas_log_start += 1; |
349 | rtas_log_size -= 1; |
350 | spin_unlock_irqrestore(lock: &rtasd_log_lock, flags: s); |
351 | |
352 | error = copy_to_user(to: buf, from: tmp, n: count) ? -EFAULT : count; |
353 | out: |
354 | kfree(objp: tmp); |
355 | return error; |
356 | } |
357 | |
358 | static __poll_t rtas_log_poll(struct file *file, poll_table * wait) |
359 | { |
360 | poll_wait(filp: file, wait_address: &rtas_log_wait, p: wait); |
361 | if (rtas_log_size) |
362 | return EPOLLIN | EPOLLRDNORM; |
363 | return 0; |
364 | } |
365 | |
366 | static const struct proc_ops rtas_log_proc_ops = { |
367 | .proc_read = rtas_log_read, |
368 | .proc_poll = rtas_log_poll, |
369 | .proc_open = rtas_log_open, |
370 | .proc_release = rtas_log_release, |
371 | .proc_lseek = noop_llseek, |
372 | }; |
373 | |
374 | static int enable_surveillance(int timeout) |
375 | { |
376 | int error; |
377 | |
378 | error = rtas_set_indicator(SURVEILLANCE_TOKEN, 0, timeout); |
379 | |
380 | if (error == 0) |
381 | return 0; |
382 | |
383 | if (error == -EINVAL) { |
384 | printk(KERN_DEBUG "rtasd: surveillance not supported\n" ); |
385 | return 0; |
386 | } |
387 | |
388 | printk(KERN_ERR "rtasd: could not update surveillance\n" ); |
389 | return -1; |
390 | } |
391 | |
392 | static void do_event_scan(void) |
393 | { |
394 | int error; |
395 | do { |
396 | memset(logdata, 0, rtas_error_log_max); |
397 | error = rtas_call(event_scan, 4, 1, NULL, |
398 | RTAS_EVENT_SCAN_ALL_EVENTS, 0, |
399 | __pa(logdata), rtas_error_log_max); |
400 | if (error == -1) { |
401 | printk(KERN_ERR "event-scan failed\n" ); |
402 | break; |
403 | } |
404 | |
405 | if (error == 0) { |
406 | if (rtas_error_type((struct rtas_error_log *)logdata) != |
407 | RTAS_TYPE_PRRN) |
408 | pSeries_log_error(logdata, ERR_TYPE_RTAS_LOG, |
409 | 0); |
410 | handle_rtas_event(log: (struct rtas_error_log *)logdata); |
411 | } |
412 | |
413 | } while(error == 0); |
414 | } |
415 | |
416 | static void rtas_event_scan(struct work_struct *w); |
417 | static DECLARE_DELAYED_WORK(event_scan_work, rtas_event_scan); |
418 | |
419 | /* |
420 | * Delay should be at least one second since some machines have problems if |
421 | * we call event-scan too quickly. |
422 | */ |
423 | static unsigned long event_scan_delay = 1*HZ; |
424 | static int first_pass = 1; |
425 | |
426 | static void rtas_event_scan(struct work_struct *w) |
427 | { |
428 | unsigned int cpu; |
429 | |
430 | do_event_scan(); |
431 | |
432 | cpus_read_lock(); |
433 | |
434 | /* raw_ OK because just using CPU as starting point. */ |
435 | cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask); |
436 | if (cpu >= nr_cpu_ids) { |
437 | cpu = cpumask_first(cpu_online_mask); |
438 | |
439 | if (first_pass) { |
440 | first_pass = 0; |
441 | event_scan_delay = 30*HZ/rtas_event_scan_rate; |
442 | |
443 | if (surveillance_timeout != -1) { |
444 | pr_debug("rtasd: enabling surveillance\n" ); |
445 | enable_surveillance(timeout: surveillance_timeout); |
446 | pr_debug("rtasd: surveillance enabled\n" ); |
447 | } |
448 | } |
449 | } |
450 | |
451 | schedule_delayed_work_on(cpu, dwork: &event_scan_work, |
452 | delay: __round_jiffies_relative(j: event_scan_delay, cpu)); |
453 | |
454 | cpus_read_unlock(); |
455 | } |
456 | |
457 | #ifdef CONFIG_PPC64 |
458 | static void __init retrieve_nvram_error_log(void) |
459 | { |
460 | unsigned int err_type ; |
461 | int rc ; |
462 | |
463 | /* See if we have any error stored in NVRAM */ |
464 | memset(logdata, 0, rtas_error_log_max); |
465 | rc = nvram_read_error_log(logdata, rtas_error_log_max, |
466 | &err_type, &error_log_cnt); |
467 | /* We can use rtas_log_buf now */ |
468 | logging_enabled = 1; |
469 | if (!rc) { |
470 | if (err_type != ERR_FLAG_ALREADY_LOGGED) { |
471 | pSeries_log_error(logdata, err_type | ERR_FLAG_BOOT, 0); |
472 | } |
473 | } |
474 | } |
475 | #else /* CONFIG_PPC64 */ |
476 | static void __init retrieve_nvram_error_log(void) |
477 | { |
478 | } |
479 | #endif /* CONFIG_PPC64 */ |
480 | |
481 | static void __init start_event_scan(void) |
482 | { |
483 | printk(KERN_DEBUG "RTAS daemon started\n" ); |
484 | pr_debug("rtasd: will sleep for %d milliseconds\n" , |
485 | (30000 / rtas_event_scan_rate)); |
486 | |
487 | /* Retrieve errors from nvram if any */ |
488 | retrieve_nvram_error_log(); |
489 | |
490 | schedule_delayed_work_on(cpu: cpumask_first(cpu_online_mask), |
491 | dwork: &event_scan_work, delay: event_scan_delay); |
492 | } |
493 | |
494 | /* Cancel the rtas event scan work */ |
495 | void rtas_cancel_event_scan(void) |
496 | { |
497 | cancel_delayed_work_sync(dwork: &event_scan_work); |
498 | } |
499 | EXPORT_SYMBOL_GPL(rtas_cancel_event_scan); |
500 | |
501 | static int __init rtas_event_scan_init(void) |
502 | { |
503 | int err; |
504 | |
505 | if (!machine_is(pseries) && !machine_is(chrp)) |
506 | return 0; |
507 | |
508 | /* No RTAS */ |
509 | event_scan = rtas_function_token(RTAS_FN_EVENT_SCAN); |
510 | if (event_scan == RTAS_UNKNOWN_SERVICE) { |
511 | printk(KERN_INFO "rtasd: No event-scan on system\n" ); |
512 | return -ENODEV; |
513 | } |
514 | |
515 | err = of_property_read_u32(rtas.dev, "rtas-event-scan-rate" , &rtas_event_scan_rate); |
516 | if (err) { |
517 | printk(KERN_ERR "rtasd: no rtas-event-scan-rate on system\n" ); |
518 | return -ENODEV; |
519 | } |
520 | |
521 | if (!rtas_event_scan_rate) { |
522 | /* Broken firmware: take a rate of zero to mean don't scan */ |
523 | printk(KERN_DEBUG "rtasd: scan rate is 0, not scanning\n" ); |
524 | return 0; |
525 | } |
526 | |
527 | /* Make room for the sequence number */ |
528 | rtas_error_log_max = rtas_get_error_log_max(); |
529 | rtas_error_log_buffer_max = rtas_error_log_max + sizeof(int); |
530 | |
531 | rtas_log_buf = vmalloc(array_size(LOG_NUMBER, |
532 | rtas_error_log_buffer_max)); |
533 | if (!rtas_log_buf) { |
534 | printk(KERN_ERR "rtasd: no memory\n" ); |
535 | return -ENOMEM; |
536 | } |
537 | |
538 | start_event_scan(); |
539 | |
540 | return 0; |
541 | } |
542 | arch_initcall(rtas_event_scan_init); |
543 | |
544 | static int __init rtas_init(void) |
545 | { |
546 | struct proc_dir_entry *entry; |
547 | |
548 | if (!machine_is(pseries) && !machine_is(chrp)) |
549 | return 0; |
550 | |
551 | if (!rtas_log_buf) |
552 | return -ENODEV; |
553 | |
554 | entry = proc_create(name: "powerpc/rtas/error_log" , mode: 0400, NULL, |
555 | proc_ops: &rtas_log_proc_ops); |
556 | if (!entry) |
557 | printk(KERN_ERR "Failed to create error_log proc entry\n" ); |
558 | |
559 | return 0; |
560 | } |
561 | __initcall(rtas_init); |
562 | |
563 | static int __init surveillance_setup(char *str) |
564 | { |
565 | int i; |
566 | |
567 | /* We only do surveillance on pseries */ |
568 | if (!machine_is(pseries)) |
569 | return 0; |
570 | |
571 | if (get_option(str: &str,pint: &i)) { |
572 | if (i >= 0 && i <= 255) |
573 | surveillance_timeout = i; |
574 | } |
575 | |
576 | return 1; |
577 | } |
578 | __setup("surveillance=" , surveillance_setup); |
579 | |
580 | static int __init rtasmsgs_setup(char *str) |
581 | { |
582 | return (kstrtobool(s: str, res: &full_rtas_msgs) == 0); |
583 | } |
584 | __setup("rtasmsgs=" , rtasmsgs_setup); |
585 | |