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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Procedures for interfacing to the RTAS on CHRP machines.
5 *
6 * Peter Bergner, IBM March 2001.
7 * Copyright (C) 2001 IBM.
8 */
9
10#include <stdarg.h>
11#include <linux/kernel.h>
12#include <linux/types.h>
13#include <linux/spinlock.h>
14#include <linux/export.h>
15#include <linux/init.h>
16#include <linux/capability.h>
17#include <linux/delay.h>
18#include <linux/cpu.h>
19#include <linux/sched.h>
20#include <linux/smp.h>
21#include <linux/completion.h>
22#include <linux/cpumask.h>
23#include <linux/memblock.h>
24#include <linux/slab.h>
25#include <linux/reboot.h>
26#include <linux/syscalls.h>
27
28#include <asm/interrupt.h>
29#include <asm/prom.h>
30#include <asm/rtas.h>
31#include <asm/hvcall.h>
32#include <asm/machdep.h>
33#include <asm/firmware.h>
34#include <asm/page.h>
35#include <asm/param.h>
36#include <asm/delay.h>
37#include <linux/uaccess.h>
38#include <asm/udbg.h>
39#include <asm/syscalls.h>
40#include <asm/smp.h>
41#include <linux/atomic.h>
42#include <asm/time.h>
43#include <asm/mmu.h>
44#include <asm/topology.h>
45#include <asm/paca.h>
46
47/* This is here deliberately so it's only used in this file */
48void enter_rtas(unsigned long);
49
50static inline void do_enter_rtas(unsigned long args)
51{
52 enter_rtas(args);
53
54 srr_regs_clobbered(); /* rtas uses SRRs, invalidate */
55}
56
57struct rtas_t rtas = {
58 .lock = __ARCH_SPIN_LOCK_UNLOCKED
59};
60EXPORT_SYMBOL(rtas);
61
62DEFINE_SPINLOCK(rtas_data_buf_lock);
63EXPORT_SYMBOL(rtas_data_buf_lock);
64
65char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
66EXPORT_SYMBOL(rtas_data_buf);
67
68unsigned long rtas_rmo_buf;
69
70/*
71 * If non-NULL, this gets called when the kernel terminates.
72 * This is done like this so rtas_flash can be a module.
73 */
74void (*rtas_flash_term_hook)(int);
75EXPORT_SYMBOL(rtas_flash_term_hook);
76
77/* RTAS use home made raw locking instead of spin_lock_irqsave
78 * because those can be called from within really nasty contexts
79 * such as having the timebase stopped which would lockup with
80 * normal locks and spinlock debugging enabled
81 */
82static unsigned long lock_rtas(void)
83{
84 unsigned long flags;
85
86 local_irq_save(flags);
87 preempt_disable();
88 arch_spin_lock(&rtas.lock);
89 return flags;
90}
91
92static void unlock_rtas(unsigned long flags)
93{
94 arch_spin_unlock(&rtas.lock);
95 local_irq_restore(flags);
96 preempt_enable();
97}
98
99/*
100 * call_rtas_display_status and call_rtas_display_status_delay
101 * are designed only for very early low-level debugging, which
102 * is why the token is hard-coded to 10.
103 */
104static void call_rtas_display_status(unsigned char c)
105{
106 unsigned long s;
107
108 if (!rtas.base)
109 return;
110
111 s = lock_rtas();
112 rtas_call_unlocked(&rtas.args, 10, 1, 1, NULL, c);
113 unlock_rtas(s);
114}
115
116static void call_rtas_display_status_delay(char c)
117{
118 static int pending_newline = 0; /* did last write end with unprinted newline? */
119 static int width = 16;
120
121 if (c == '\n') {
122 while (width-- > 0)
123 call_rtas_display_status(' ');
124 width = 16;
125 mdelay(500);
126 pending_newline = 1;
127 } else {
128 if (pending_newline) {
129 call_rtas_display_status('\r');
130 call_rtas_display_status('\n');
131 }
132 pending_newline = 0;
133 if (width--) {
134 call_rtas_display_status(c);
135 udelay(10000);
136 }
137 }
138}
139
140void __init udbg_init_rtas_panel(void)
141{
142 udbg_putc = call_rtas_display_status_delay;
143}
144
145#ifdef CONFIG_UDBG_RTAS_CONSOLE
146
147/* If you think you're dying before early_init_dt_scan_rtas() does its
148 * work, you can hard code the token values for your firmware here and
149 * hardcode rtas.base/entry etc.
150 */
151static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
152static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
153
154static void udbg_rtascon_putc(char c)
155{
156 int tries;
157
158 if (!rtas.base)
159 return;
160
161 /* Add CRs before LFs */
162 if (c == '\n')
163 udbg_rtascon_putc('\r');
164
165 /* if there is more than one character to be displayed, wait a bit */
166 for (tries = 0; tries < 16; tries++) {
167 if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
168 break;
169 udelay(1000);
170 }
171}
172
173static int udbg_rtascon_getc_poll(void)
174{
175 int c;
176
177 if (!rtas.base)
178 return -1;
179
180 if (rtas_call(rtas_getchar_token, 0, 2, &c))
181 return -1;
182
183 return c;
184}
185
186static int udbg_rtascon_getc(void)
187{
188 int c;
189
190 while ((c = udbg_rtascon_getc_poll()) == -1)
191 ;
192
193 return c;
194}
195
196
197void __init udbg_init_rtas_console(void)
198{
199 udbg_putc = udbg_rtascon_putc;
200 udbg_getc = udbg_rtascon_getc;
201 udbg_getc_poll = udbg_rtascon_getc_poll;
202}
203#endif /* CONFIG_UDBG_RTAS_CONSOLE */
204
205void rtas_progress(char *s, unsigned short hex)
206{
207 struct device_node *root;
208 int width;
209 const __be32 *p;
210 char *os;
211 static int display_character, set_indicator;
212 static int display_width, display_lines, form_feed;
213 static const int *row_width;
214 static DEFINE_SPINLOCK(progress_lock);
215 static int current_line;
216 static int pending_newline = 0; /* did last write end with unprinted newline? */
217
218 if (!rtas.base)
219 return;
220
221 if (display_width == 0) {
222 display_width = 0x10;
223 if ((root = of_find_node_by_path("/rtas"))) {
224 if ((p = of_get_property(root,
225 "ibm,display-line-length", NULL)))
226 display_width = be32_to_cpu(*p);
227 if ((p = of_get_property(root,
228 "ibm,form-feed", NULL)))
229 form_feed = be32_to_cpu(*p);
230 if ((p = of_get_property(root,
231 "ibm,display-number-of-lines", NULL)))
232 display_lines = be32_to_cpu(*p);
233 row_width = of_get_property(root,
234 "ibm,display-truncation-length", NULL);
235 of_node_put(root);
236 }
237 display_character = rtas_token("display-character");
238 set_indicator = rtas_token("set-indicator");
239 }
240
241 if (display_character == RTAS_UNKNOWN_SERVICE) {
242 /* use hex display if available */
243 if (set_indicator != RTAS_UNKNOWN_SERVICE)
244 rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
245 return;
246 }
247
248 spin_lock(&progress_lock);
249
250 /*
251 * Last write ended with newline, but we didn't print it since
252 * it would just clear the bottom line of output. Print it now
253 * instead.
254 *
255 * If no newline is pending and form feed is supported, clear the
256 * display with a form feed; otherwise, print a CR to start output
257 * at the beginning of the line.
258 */
259 if (pending_newline) {
260 rtas_call(display_character, 1, 1, NULL, '\r');
261 rtas_call(display_character, 1, 1, NULL, '\n');
262 pending_newline = 0;
263 } else {
264 current_line = 0;
265 if (form_feed)
266 rtas_call(display_character, 1, 1, NULL,
267 (char)form_feed);
268 else
269 rtas_call(display_character, 1, 1, NULL, '\r');
270 }
271
272 if (row_width)
273 width = row_width[current_line];
274 else
275 width = display_width;
276 os = s;
277 while (*os) {
278 if (*os == '\n' || *os == '\r') {
279 /* If newline is the last character, save it
280 * until next call to avoid bumping up the
281 * display output.
282 */
283 if (*os == '\n' && !os[1]) {
284 pending_newline = 1;
285 current_line++;
286 if (current_line > display_lines-1)
287 current_line = display_lines-1;
288 spin_unlock(&progress_lock);
289 return;
290 }
291
292 /* RTAS wants CR-LF, not just LF */
293
294 if (*os == '\n') {
295 rtas_call(display_character, 1, 1, NULL, '\r');
296 rtas_call(display_character, 1, 1, NULL, '\n');
297 } else {
298 /* CR might be used to re-draw a line, so we'll
299 * leave it alone and not add LF.
300 */
301 rtas_call(display_character, 1, 1, NULL, *os);
302 }
303
304 if (row_width)
305 width = row_width[current_line];
306 else
307 width = display_width;
308 } else {
309 width--;
310 rtas_call(display_character, 1, 1, NULL, *os);
311 }
312
313 os++;
314
315 /* if we overwrite the screen length */
316 if (width <= 0)
317 while ((*os != 0) && (*os != '\n') && (*os != '\r'))
318 os++;
319 }
320
321 spin_unlock(&progress_lock);
322}
323EXPORT_SYMBOL(rtas_progress); /* needed by rtas_flash module */
324
325int rtas_token(const char *service)
326{
327 const __be32 *tokp;
328 if (rtas.dev == NULL)
329 return RTAS_UNKNOWN_SERVICE;
330 tokp = of_get_property(rtas.dev, service, NULL);
331 return tokp ? be32_to_cpu(*tokp) : RTAS_UNKNOWN_SERVICE;
332}
333EXPORT_SYMBOL(rtas_token);
334
335int rtas_service_present(const char *service)
336{
337 return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
338}
339EXPORT_SYMBOL(rtas_service_present);
340
341#ifdef CONFIG_RTAS_ERROR_LOGGING
342/*
343 * Return the firmware-specified size of the error log buffer
344 * for all rtas calls that require an error buffer argument.
345 * This includes 'check-exception' and 'rtas-last-error'.
346 */
347int rtas_get_error_log_max(void)
348{
349 static int rtas_error_log_max;
350 if (rtas_error_log_max)
351 return rtas_error_log_max;
352
353 rtas_error_log_max = rtas_token ("rtas-error-log-max");
354 if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
355 (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
356 printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
357 rtas_error_log_max);
358 rtas_error_log_max = RTAS_ERROR_LOG_MAX;
359 }
360 return rtas_error_log_max;
361}
362EXPORT_SYMBOL(rtas_get_error_log_max);
363
364
365static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
366static int rtas_last_error_token;
367
368/** Return a copy of the detailed error text associated with the
369 * most recent failed call to rtas. Because the error text
370 * might go stale if there are any other intervening rtas calls,
371 * this routine must be called atomically with whatever produced
372 * the error (i.e. with rtas.lock still held from the previous call).
373 */
374static char *__fetch_rtas_last_error(char *altbuf)
375{
376 struct rtas_args err_args, save_args;
377 u32 bufsz;
378 char *buf = NULL;
379
380 if (rtas_last_error_token == -1)
381 return NULL;
382
383 bufsz = rtas_get_error_log_max();
384
385 err_args.token = cpu_to_be32(rtas_last_error_token);
386 err_args.nargs = cpu_to_be32(2);
387 err_args.nret = cpu_to_be32(1);
388 err_args.args[0] = cpu_to_be32(__pa(rtas_err_buf));
389 err_args.args[1] = cpu_to_be32(bufsz);
390 err_args.args[2] = 0;
391
392 save_args = rtas.args;
393 rtas.args = err_args;
394
395 do_enter_rtas(__pa(&rtas.args));
396
397 err_args = rtas.args;
398 rtas.args = save_args;
399
400 /* Log the error in the unlikely case that there was one. */
401 if (unlikely(err_args.args[2] == 0)) {
402 if (altbuf) {
403 buf = altbuf;
404 } else {
405 buf = rtas_err_buf;
406 if (slab_is_available())
407 buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
408 }
409 if (buf)
410 memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
411 }
412
413 return buf;
414}
415
416#define get_errorlog_buffer() kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
417
418#else /* CONFIG_RTAS_ERROR_LOGGING */
419#define __fetch_rtas_last_error(x) NULL
420#define get_errorlog_buffer() NULL
421#endif
422
423
424static void
425va_rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret,
426 va_list list)
427{
428 int i;
429
430 args->token = cpu_to_be32(token);
431 args->nargs = cpu_to_be32(nargs);
432 args->nret = cpu_to_be32(nret);
433 args->rets = &(args->args[nargs]);
434
435 for (i = 0; i < nargs; ++i)
436 args->args[i] = cpu_to_be32(va_arg(list, __u32));
437
438 for (i = 0; i < nret; ++i)
439 args->rets[i] = 0;
440
441 do_enter_rtas(__pa(args));
442}
443
444void rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret, ...)
445{
446 va_list list;
447
448 va_start(list, nret);
449 va_rtas_call_unlocked(args, token, nargs, nret, list);
450 va_end(list);
451}
452
453int rtas_call(int token, int nargs, int nret, int *outputs, ...)
454{
455 va_list list;
456 int i;
457 unsigned long s;
458 struct rtas_args *rtas_args;
459 char *buff_copy = NULL;
460 int ret;
461
462 if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
463 return -1;
464
465 s = lock_rtas();
466
467 /* We use the global rtas args buffer */
468 rtas_args = &rtas.args;
469
470 va_start(list, outputs);
471 va_rtas_call_unlocked(rtas_args, token, nargs, nret, list);
472 va_end(list);
473
474 /* A -1 return code indicates that the last command couldn't
475 be completed due to a hardware error. */
476 if (be32_to_cpu(rtas_args->rets[0]) == -1)
477 buff_copy = __fetch_rtas_last_error(NULL);
478
479 if (nret > 1 && outputs != NULL)
480 for (i = 0; i < nret-1; ++i)
481 outputs[i] = be32_to_cpu(rtas_args->rets[i+1]);
482 ret = (nret > 0)? be32_to_cpu(rtas_args->rets[0]): 0;
483
484 unlock_rtas(s);
485
486 if (buff_copy) {
487 log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
488 if (slab_is_available())
489 kfree(buff_copy);
490 }
491 return ret;
492}
493EXPORT_SYMBOL(rtas_call);
494
495/* For RTAS_BUSY (-2), delay for 1 millisecond. For an extended busy status
496 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
497 */
498unsigned int rtas_busy_delay_time(int status)
499{
500 int order;
501 unsigned int ms = 0;
502
503 if (status == RTAS_BUSY) {
504 ms = 1;
505 } else if (status >= RTAS_EXTENDED_DELAY_MIN &&
506 status <= RTAS_EXTENDED_DELAY_MAX) {
507 order = status - RTAS_EXTENDED_DELAY_MIN;
508 for (ms = 1; order > 0; order--)
509 ms *= 10;
510 }
511
512 return ms;
513}
514EXPORT_SYMBOL(rtas_busy_delay_time);
515
516/* For an RTAS busy status code, perform the hinted delay. */
517unsigned int rtas_busy_delay(int status)
518{
519 unsigned int ms;
520
521 might_sleep();
522 ms = rtas_busy_delay_time(status);
523 if (ms && need_resched())
524 msleep(ms);
525
526 return ms;
527}
528EXPORT_SYMBOL(rtas_busy_delay);
529
530static int rtas_error_rc(int rtas_rc)
531{
532 int rc;
533
534 switch (rtas_rc) {
535 case -1: /* Hardware Error */
536 rc = -EIO;
537 break;
538 case -3: /* Bad indicator/domain/etc */
539 rc = -EINVAL;
540 break;
541 case -9000: /* Isolation error */
542 rc = -EFAULT;
543 break;
544 case -9001: /* Outstanding TCE/PTE */
545 rc = -EEXIST;
546 break;
547 case -9002: /* No usable slot */
548 rc = -ENODEV;
549 break;
550 default:
551 printk(KERN_ERR "%s: unexpected RTAS error %d\n",
552 __func__, rtas_rc);
553 rc = -ERANGE;
554 break;
555 }
556 return rc;
557}
558
559int rtas_get_power_level(int powerdomain, int *level)
560{
561 int token = rtas_token("get-power-level");
562 int rc;
563
564 if (token == RTAS_UNKNOWN_SERVICE)
565 return -ENOENT;
566
567 while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
568 udelay(1);
569
570 if (rc < 0)
571 return rtas_error_rc(rc);
572 return rc;
573}
574EXPORT_SYMBOL(rtas_get_power_level);
575
576int rtas_set_power_level(int powerdomain, int level, int *setlevel)
577{
578 int token = rtas_token("set-power-level");
579 int rc;
580
581 if (token == RTAS_UNKNOWN_SERVICE)
582 return -ENOENT;
583
584 do {
585 rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
586 } while (rtas_busy_delay(rc));
587
588 if (rc < 0)
589 return rtas_error_rc(rc);
590 return rc;
591}
592EXPORT_SYMBOL(rtas_set_power_level);
593
594int rtas_get_sensor(int sensor, int index, int *state)
595{
596 int token = rtas_token("get-sensor-state");
597 int rc;
598
599 if (token == RTAS_UNKNOWN_SERVICE)
600 return -ENOENT;
601
602 do {
603 rc = rtas_call(token, 2, 2, state, sensor, index);
604 } while (rtas_busy_delay(rc));
605
606 if (rc < 0)
607 return rtas_error_rc(rc);
608 return rc;
609}
610EXPORT_SYMBOL(rtas_get_sensor);
611
612int rtas_get_sensor_fast(int sensor, int index, int *state)
613{
614 int token = rtas_token("get-sensor-state");
615 int rc;
616
617 if (token == RTAS_UNKNOWN_SERVICE)
618 return -ENOENT;
619
620 rc = rtas_call(token, 2, 2, state, sensor, index);
621 WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
622 rc <= RTAS_EXTENDED_DELAY_MAX));
623
624 if (rc < 0)
625 return rtas_error_rc(rc);
626 return rc;
627}
628
629bool rtas_indicator_present(int token, int *maxindex)
630{
631 int proplen, count, i;
632 const struct indicator_elem {
633 __be32 token;
634 __be32 maxindex;
635 } *indicators;
636
637 indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
638 if (!indicators)
639 return false;
640
641 count = proplen / sizeof(struct indicator_elem);
642
643 for (i = 0; i < count; i++) {
644 if (__be32_to_cpu(indicators[i].token) != token)
645 continue;
646 if (maxindex)
647 *maxindex = __be32_to_cpu(indicators[i].maxindex);
648 return true;
649 }
650
651 return false;
652}
653EXPORT_SYMBOL(rtas_indicator_present);
654
655int rtas_set_indicator(int indicator, int index, int new_value)
656{
657 int token = rtas_token("set-indicator");
658 int rc;
659
660 if (token == RTAS_UNKNOWN_SERVICE)
661 return -ENOENT;
662
663 do {
664 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
665 } while (rtas_busy_delay(rc));
666
667 if (rc < 0)
668 return rtas_error_rc(rc);
669 return rc;
670}
671EXPORT_SYMBOL(rtas_set_indicator);
672
673/*
674 * Ignoring RTAS extended delay
675 */
676int rtas_set_indicator_fast(int indicator, int index, int new_value)
677{
678 int rc;
679 int token = rtas_token("set-indicator");
680
681 if (token == RTAS_UNKNOWN_SERVICE)
682 return -ENOENT;
683
684 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
685
686 WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
687 rc <= RTAS_EXTENDED_DELAY_MAX));
688
689 if (rc < 0)
690 return rtas_error_rc(rc);
691
692 return rc;
693}
694
695/**
696 * rtas_ibm_suspend_me() - Call ibm,suspend-me to suspend the LPAR.
697 *
698 * @fw_status: RTAS call status will be placed here if not NULL.
699 *
700 * rtas_ibm_suspend_me() should be called only on a CPU which has
701 * received H_CONTINUE from the H_JOIN hcall. All other active CPUs
702 * should be waiting to return from H_JOIN.
703 *
704 * rtas_ibm_suspend_me() may suspend execution of the OS
705 * indefinitely. Callers should take appropriate measures upon return, such as
706 * resetting watchdog facilities.
707 *
708 * Callers may choose to retry this call if @fw_status is
709 * %RTAS_THREADS_ACTIVE.
710 *
711 * Return:
712 * 0 - The partition has resumed from suspend, possibly after
713 * migration to a different host.
714 * -ECANCELED - The operation was aborted.
715 * -EAGAIN - There were other CPUs not in H_JOIN at the time of the call.
716 * -EBUSY - Some other condition prevented the suspend from succeeding.
717 * -EIO - Hardware/platform error.
718 */
719int rtas_ibm_suspend_me(int *fw_status)
720{
721 int fwrc;
722 int ret;
723
724 fwrc = rtas_call(rtas_token("ibm,suspend-me"), 0, 1, NULL);
725
726 switch (fwrc) {
727 case 0:
728 ret = 0;
729 break;
730 case RTAS_SUSPEND_ABORTED:
731 ret = -ECANCELED;
732 break;
733 case RTAS_THREADS_ACTIVE:
734 ret = -EAGAIN;
735 break;
736 case RTAS_NOT_SUSPENDABLE:
737 case RTAS_OUTSTANDING_COPROC:
738 ret = -EBUSY;
739 break;
740 case -1:
741 default:
742 ret = -EIO;
743 break;
744 }
745
746 if (fw_status)
747 *fw_status = fwrc;
748
749 return ret;
750}
751
752void __noreturn rtas_restart(char *cmd)
753{
754 if (rtas_flash_term_hook)
755 rtas_flash_term_hook(SYS_RESTART);
756 printk("RTAS system-reboot returned %d\n",
757 rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
758 for (;;);
759}
760
761void rtas_power_off(void)
762{
763 if (rtas_flash_term_hook)
764 rtas_flash_term_hook(SYS_POWER_OFF);
765 /* allow power on only with power button press */
766 printk("RTAS power-off returned %d\n",
767 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
768 for (;;);
769}
770
771void __noreturn rtas_halt(void)
772{
773 if (rtas_flash_term_hook)
774 rtas_flash_term_hook(SYS_HALT);
775 /* allow power on only with power button press */
776 printk("RTAS power-off returned %d\n",
777 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
778 for (;;);
779}
780
781/* Must be in the RMO region, so we place it here */
782static char rtas_os_term_buf[2048];
783
784void rtas_os_term(char *str)
785{
786 int status;
787
788 /*
789 * Firmware with the ibm,extended-os-term property is guaranteed
790 * to always return from an ibm,os-term call. Earlier versions without
791 * this property may terminate the partition which we want to avoid
792 * since it interferes with panic_timeout.
793 */
794 if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
795 RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
796 return;
797
798 snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
799
800 do {
801 status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
802 __pa(rtas_os_term_buf));
803 } while (rtas_busy_delay(status));
804
805 if (status != 0)
806 printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
807}
808
809/**
810 * rtas_activate_firmware() - Activate a new version of firmware.
811 *
812 * Activate a new version of partition firmware. The OS must call this
813 * after resuming from a partition hibernation or migration in order
814 * to maintain the ability to perform live firmware updates. It's not
815 * catastrophic for this method to be absent or to fail; just log the
816 * condition in that case.
817 *
818 * Context: This function may sleep.
819 */
820void rtas_activate_firmware(void)
821{
822 int token;
823 int fwrc;
824
825 token = rtas_token("ibm,activate-firmware");
826 if (token == RTAS_UNKNOWN_SERVICE) {
827 pr_notice("ibm,activate-firmware method unavailable\n");
828 return;
829 }
830
831 do {
832 fwrc = rtas_call(token, 0, 1, NULL);
833 } while (rtas_busy_delay(fwrc));
834
835 if (fwrc)
836 pr_err("ibm,activate-firmware failed (%i)\n", fwrc);
837}
838
839#ifdef CONFIG_PPC_PSERIES
840/**
841 * rtas_call_reentrant() - Used for reentrant rtas calls
842 * @token: Token for desired reentrant RTAS call
843 * @nargs: Number of Input Parameters
844 * @nret: Number of Output Parameters
845 * @outputs: Array of outputs
846 * @...: Inputs for desired RTAS call
847 *
848 * According to LoPAR documentation, only "ibm,int-on", "ibm,int-off",
849 * "ibm,get-xive" and "ibm,set-xive" are currently reentrant.
850 * Reentrant calls need their own rtas_args buffer, so not using rtas.args, but
851 * PACA one instead.
852 *
853 * Return: -1 on error,
854 * First output value of RTAS call if (nret > 0),
855 * 0 otherwise,
856 */
857int rtas_call_reentrant(int token, int nargs, int nret, int *outputs, ...)
858{
859 va_list list;
860 struct rtas_args *args;
861 unsigned long flags;
862 int i, ret = 0;
863
864 if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
865 return -1;
866
867 local_irq_save(flags);
868 preempt_disable();
869
870 /* We use the per-cpu (PACA) rtas args buffer */
871 args = local_paca->rtas_args_reentrant;
872
873 va_start(list, outputs);
874 va_rtas_call_unlocked(args, token, nargs, nret, list);
875 va_end(list);
876
877 if (nret > 1 && outputs)
878 for (i = 0; i < nret - 1; ++i)
879 outputs[i] = be32_to_cpu(args->rets[i + 1]);
880
881 if (nret > 0)
882 ret = be32_to_cpu(args->rets[0]);
883
884 local_irq_restore(flags);
885 preempt_enable();
886
887 return ret;
888}
889
890#endif /* CONFIG_PPC_PSERIES */
891
892/**
893 * Find a specific pseries error log in an RTAS extended event log.
894 * @log: RTAS error/event log
895 * @section_id: two character section identifier
896 *
897 * Returns a pointer to the specified errorlog or NULL if not found.
898 */
899struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
900 uint16_t section_id)
901{
902 struct rtas_ext_event_log_v6 *ext_log =
903 (struct rtas_ext_event_log_v6 *)log->buffer;
904 struct pseries_errorlog *sect;
905 unsigned char *p, *log_end;
906 uint32_t ext_log_length = rtas_error_extended_log_length(log);
907 uint8_t log_format = rtas_ext_event_log_format(ext_log);
908 uint32_t company_id = rtas_ext_event_company_id(ext_log);
909
910 /* Check that we understand the format */
911 if (ext_log_length < sizeof(struct rtas_ext_event_log_v6) ||
912 log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
913 company_id != RTAS_V6EXT_COMPANY_ID_IBM)
914 return NULL;
915
916 log_end = log->buffer + ext_log_length;
917 p = ext_log->vendor_log;
918
919 while (p < log_end) {
920 sect = (struct pseries_errorlog *)p;
921 if (pseries_errorlog_id(sect) == section_id)
922 return sect;
923 p += pseries_errorlog_length(sect);
924 }
925
926 return NULL;
927}
928
929#ifdef CONFIG_PPC_RTAS_FILTER
930
931/*
932 * The sys_rtas syscall, as originally designed, allows root to pass
933 * arbitrary physical addresses to RTAS calls. A number of RTAS calls
934 * can be abused to write to arbitrary memory and do other things that
935 * are potentially harmful to system integrity, and thus should only
936 * be used inside the kernel and not exposed to userspace.
937 *
938 * All known legitimate users of the sys_rtas syscall will only ever
939 * pass addresses that fall within the RMO buffer, and use a known
940 * subset of RTAS calls.
941 *
942 * Accordingly, we filter RTAS requests to check that the call is
943 * permitted, and that provided pointers fall within the RMO buffer.
944 * The rtas_filters list contains an entry for each permitted call,
945 * with the indexes of the parameters which are expected to contain
946 * addresses and sizes of buffers allocated inside the RMO buffer.
947 */
948struct rtas_filter {
949 const char *name;
950 int token;
951 /* Indexes into the args buffer, -1 if not used */
952 int buf_idx1;
953 int size_idx1;
954 int buf_idx2;
955 int size_idx2;
956
957 int fixed_size;
958};
959
960static struct rtas_filter rtas_filters[] __ro_after_init = {
961 { "ibm,activate-firmware", -1, -1, -1, -1, -1 },
962 { "ibm,configure-connector", -1, 0, -1, 1, -1, 4096 }, /* Special cased */
963 { "display-character", -1, -1, -1, -1, -1 },
964 { "ibm,display-message", -1, 0, -1, -1, -1 },
965 { "ibm,errinjct", -1, 2, -1, -1, -1, 1024 },
966 { "ibm,close-errinjct", -1, -1, -1, -1, -1 },
967 { "ibm,open-errinjct", -1, -1, -1, -1, -1 },
968 { "ibm,get-config-addr-info2", -1, -1, -1, -1, -1 },
969 { "ibm,get-dynamic-sensor-state", -1, 1, -1, -1, -1 },
970 { "ibm,get-indices", -1, 2, 3, -1, -1 },
971 { "get-power-level", -1, -1, -1, -1, -1 },
972 { "get-sensor-state", -1, -1, -1, -1, -1 },
973 { "ibm,get-system-parameter", -1, 1, 2, -1, -1 },
974 { "get-time-of-day", -1, -1, -1, -1, -1 },
975 { "ibm,get-vpd", -1, 0, -1, 1, 2 },
976 { "ibm,lpar-perftools", -1, 2, 3, -1, -1 },
977 { "ibm,platform-dump", -1, 4, 5, -1, -1 },
978 { "ibm,read-slot-reset-state", -1, -1, -1, -1, -1 },
979 { "ibm,scan-log-dump", -1, 0, 1, -1, -1 },
980 { "ibm,set-dynamic-indicator", -1, 2, -1, -1, -1 },
981 { "ibm,set-eeh-option", -1, -1, -1, -1, -1 },
982 { "set-indicator", -1, -1, -1, -1, -1 },
983 { "set-power-level", -1, -1, -1, -1, -1 },
984 { "set-time-for-power-on", -1, -1, -1, -1, -1 },
985 { "ibm,set-system-parameter", -1, 1, -1, -1, -1 },
986 { "set-time-of-day", -1, -1, -1, -1, -1 },
987#ifdef CONFIG_CPU_BIG_ENDIAN
988 { "ibm,suspend-me", -1, -1, -1, -1, -1 },
989 { "ibm,update-nodes", -1, 0, -1, -1, -1, 4096 },
990 { "ibm,update-properties", -1, 0, -1, -1, -1, 4096 },
991#endif
992 { "ibm,physical-attestation", -1, 0, 1, -1, -1 },
993};
994
995static bool in_rmo_buf(u32 base, u32 end)
996{
997 return base >= rtas_rmo_buf &&
998 base < (rtas_rmo_buf + RTAS_USER_REGION_SIZE) &&
999 base <= end &&
1000 end >= rtas_rmo_buf &&
1001 end < (rtas_rmo_buf + RTAS_USER_REGION_SIZE);
1002}
1003
1004static bool block_rtas_call(int token, int nargs,
1005 struct rtas_args *args)
1006{
1007 int i;
1008
1009 for (i = 0; i < ARRAY_SIZE(rtas_filters); i++) {
1010 struct rtas_filter *f = &rtas_filters[i];
1011 u32 base, size, end;
1012
1013 if (token != f->token)
1014 continue;
1015
1016 if (f->buf_idx1 != -1) {
1017 base = be32_to_cpu(args->args[f->buf_idx1]);
1018 if (f->size_idx1 != -1)
1019 size = be32_to_cpu(args->args[f->size_idx1]);
1020 else if (f->fixed_size)
1021 size = f->fixed_size;
1022 else
1023 size = 1;
1024
1025 end = base + size - 1;
1026 if (!in_rmo_buf(base, end))
1027 goto err;
1028 }
1029
1030 if (f->buf_idx2 != -1) {
1031 base = be32_to_cpu(args->args[f->buf_idx2]);
1032 if (f->size_idx2 != -1)
1033 size = be32_to_cpu(args->args[f->size_idx2]);
1034 else if (f->fixed_size)
1035 size = f->fixed_size;
1036 else
1037 size = 1;
1038 end = base + size - 1;
1039
1040 /*
1041 * Special case for ibm,configure-connector where the
1042 * address can be 0
1043 */
1044 if (!strcmp(f->name, "ibm,configure-connector") &&
1045 base == 0)
1046 return false;
1047
1048 if (!in_rmo_buf(base, end))
1049 goto err;
1050 }
1051
1052 return false;
1053 }
1054
1055err:
1056 pr_err_ratelimited("sys_rtas: RTAS call blocked - exploit attempt?\n");
1057 pr_err_ratelimited("sys_rtas: token=0x%x, nargs=%d (called by %s)\n",
1058 token, nargs, current->comm);
1059 return true;
1060}
1061
1062static void __init rtas_syscall_filter_init(void)
1063{
1064 unsigned int i;
1065
1066 for (i = 0; i < ARRAY_SIZE(rtas_filters); i++)
1067 rtas_filters[i].token = rtas_token(rtas_filters[i].name);
1068}
1069
1070#else
1071
1072static bool block_rtas_call(int token, int nargs,
1073 struct rtas_args *args)
1074{
1075 return false;
1076}
1077
1078static void __init rtas_syscall_filter_init(void)
1079{
1080}
1081
1082#endif /* CONFIG_PPC_RTAS_FILTER */
1083
1084/* We assume to be passed big endian arguments */
1085SYSCALL_DEFINE1(rtas, struct rtas_args __user *, uargs)
1086{
1087 struct rtas_args args;
1088 unsigned long flags;
1089 char *buff_copy, *errbuf = NULL;
1090 int nargs, nret, token;
1091
1092 if (!capable(CAP_SYS_ADMIN))
1093 return -EPERM;
1094
1095 if (!rtas.entry)
1096 return -EINVAL;
1097
1098 if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
1099 return -EFAULT;
1100
1101 nargs = be32_to_cpu(args.nargs);
1102 nret = be32_to_cpu(args.nret);
1103 token = be32_to_cpu(args.token);
1104
1105 if (nargs >= ARRAY_SIZE(args.args)
1106 || nret > ARRAY_SIZE(args.args)
1107 || nargs + nret > ARRAY_SIZE(args.args))
1108 return -EINVAL;
1109
1110 /* Copy in args. */
1111 if (copy_from_user(args.args, uargs->args,
1112 nargs * sizeof(rtas_arg_t)) != 0)
1113 return -EFAULT;
1114
1115 if (token == RTAS_UNKNOWN_SERVICE)
1116 return -EINVAL;
1117
1118 args.rets = &args.args[nargs];
1119 memset(args.rets, 0, nret * sizeof(rtas_arg_t));
1120
1121 if (block_rtas_call(token, nargs, &args))
1122 return -EINVAL;
1123
1124 /* Need to handle ibm,suspend_me call specially */
1125 if (token == rtas_token("ibm,suspend-me")) {
1126
1127 /*
1128 * rtas_ibm_suspend_me assumes the streamid handle is in cpu
1129 * endian, or at least the hcall within it requires it.
1130 */
1131 int rc = 0;
1132 u64 handle = ((u64)be32_to_cpu(args.args[0]) << 32)
1133 | be32_to_cpu(args.args[1]);
1134 rc = rtas_syscall_dispatch_ibm_suspend_me(handle);
1135 if (rc == -EAGAIN)
1136 args.rets[0] = cpu_to_be32(RTAS_NOT_SUSPENDABLE);
1137 else if (rc == -EIO)
1138 args.rets[0] = cpu_to_be32(-1);
1139 else if (rc)
1140 return rc;
1141 goto copy_return;
1142 }
1143
1144 buff_copy = get_errorlog_buffer();
1145
1146 flags = lock_rtas();
1147
1148 rtas.args = args;
1149 do_enter_rtas(__pa(&rtas.args));
1150 args = rtas.args;
1151
1152 /* A -1 return code indicates that the last command couldn't
1153 be completed due to a hardware error. */
1154 if (be32_to_cpu(args.rets[0]) == -1)
1155 errbuf = __fetch_rtas_last_error(buff_copy);
1156
1157 unlock_rtas(flags);
1158
1159 if (buff_copy) {
1160 if (errbuf)
1161 log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
1162 kfree(buff_copy);
1163 }
1164
1165 copy_return:
1166 /* Copy out args. */
1167 if (copy_to_user(uargs->args + nargs,
1168 args.args + nargs,
1169 nret * sizeof(rtas_arg_t)) != 0)
1170 return -EFAULT;
1171
1172 return 0;
1173}
1174
1175/*
1176 * Call early during boot, before mem init, to retrieve the RTAS
1177 * information from the device-tree and allocate the RMO buffer for userland
1178 * accesses.
1179 */
1180void __init rtas_initialize(void)
1181{
1182 unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
1183 u32 base, size, entry;
1184 int no_base, no_size, no_entry;
1185
1186 /* Get RTAS dev node and fill up our "rtas" structure with infos
1187 * about it.
1188 */
1189 rtas.dev = of_find_node_by_name(NULL, "rtas");
1190 if (!rtas.dev)
1191 return;
1192
1193 no_base = of_property_read_u32(rtas.dev, "linux,rtas-base", &base);
1194 no_size = of_property_read_u32(rtas.dev, "rtas-size", &size);
1195 if (no_base || no_size) {
1196 of_node_put(rtas.dev);
1197 rtas.dev = NULL;
1198 return;
1199 }
1200
1201 rtas.base = base;
1202 rtas.size = size;
1203 no_entry = of_property_read_u32(rtas.dev, "linux,rtas-entry", &entry);
1204 rtas.entry = no_entry ? rtas.base : entry;
1205
1206 /* If RTAS was found, allocate the RMO buffer for it and look for
1207 * the stop-self token if any
1208 */
1209#ifdef CONFIG_PPC64
1210 if (firmware_has_feature(FW_FEATURE_LPAR))
1211 rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
1212#endif
1213 rtas_rmo_buf = memblock_phys_alloc_range(RTAS_USER_REGION_SIZE, PAGE_SIZE,
1214 0, rtas_region);
1215 if (!rtas_rmo_buf)
1216 panic("ERROR: RTAS: Failed to allocate %lx bytes below %pa\n",
1217 PAGE_SIZE, &rtas_region);
1218
1219#ifdef CONFIG_RTAS_ERROR_LOGGING
1220 rtas_last_error_token = rtas_token("rtas-last-error");
1221#endif
1222
1223 rtas_syscall_filter_init();
1224}
1225
1226int __init early_init_dt_scan_rtas(unsigned long node,
1227 const char *uname, int depth, void *data)
1228{
1229 const u32 *basep, *entryp, *sizep;
1230
1231 if (depth != 1 || strcmp(uname, "rtas") != 0)
1232 return 0;
1233
1234 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
1235 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
1236 sizep = of_get_flat_dt_prop(node, "rtas-size", NULL);
1237
1238 if (basep && entryp && sizep) {
1239 rtas.base = *basep;
1240 rtas.entry = *entryp;
1241 rtas.size = *sizep;
1242 }
1243
1244#ifdef CONFIG_UDBG_RTAS_CONSOLE
1245 basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1246 if (basep)
1247 rtas_putchar_token = *basep;
1248
1249 basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1250 if (basep)
1251 rtas_getchar_token = *basep;
1252
1253 if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1254 rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1255 udbg_init_rtas_console();
1256
1257#endif
1258
1259 /* break now */
1260 return 1;
1261}
1262
1263static arch_spinlock_t timebase_lock;
1264static u64 timebase = 0;
1265
1266void rtas_give_timebase(void)
1267{
1268 unsigned long flags;
1269
1270 local_irq_save(flags);
1271 hard_irq_disable();
1272 arch_spin_lock(&timebase_lock);
1273 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1274 timebase = get_tb();
1275 arch_spin_unlock(&timebase_lock);
1276
1277 while (timebase)
1278 barrier();
1279 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1280 local_irq_restore(flags);
1281}
1282
1283void rtas_take_timebase(void)
1284{
1285 while (!timebase)
1286 barrier();
1287 arch_spin_lock(&timebase_lock);
1288 set_tb(timebase >> 32, timebase & 0xffffffff);
1289 timebase = 0;
1290 arch_spin_unlock(&timebase_lock);
1291}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Procedures for interfacing to the RTAS on CHRP machines.
5 *
6 * Peter Bergner, IBM March 2001.
7 * Copyright (C) 2001 IBM.
8 */
9
10#include <stdarg.h>
11#include <linux/kernel.h>
12#include <linux/types.h>
13#include <linux/spinlock.h>
14#include <linux/export.h>
15#include <linux/init.h>
16#include <linux/capability.h>
17#include <linux/delay.h>
18#include <linux/cpu.h>
19#include <linux/sched.h>
20#include <linux/smp.h>
21#include <linux/completion.h>
22#include <linux/cpumask.h>
23#include <linux/memblock.h>
24#include <linux/slab.h>
25#include <linux/reboot.h>
26#include <linux/syscalls.h>
27
28#include <asm/prom.h>
29#include <asm/rtas.h>
30#include <asm/hvcall.h>
31#include <asm/machdep.h>
32#include <asm/firmware.h>
33#include <asm/page.h>
34#include <asm/param.h>
35#include <asm/delay.h>
36#include <linux/uaccess.h>
37#include <asm/udbg.h>
38#include <asm/syscalls.h>
39#include <asm/smp.h>
40#include <linux/atomic.h>
41#include <asm/time.h>
42#include <asm/mmu.h>
43#include <asm/topology.h>
44
45/* This is here deliberately so it's only used in this file */
46void enter_rtas(unsigned long);
47
48struct rtas_t rtas = {
49 .lock = __ARCH_SPIN_LOCK_UNLOCKED
50};
51EXPORT_SYMBOL(rtas);
52
53DEFINE_SPINLOCK(rtas_data_buf_lock);
54EXPORT_SYMBOL(rtas_data_buf_lock);
55
56char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
57EXPORT_SYMBOL(rtas_data_buf);
58
59unsigned long rtas_rmo_buf;
60
61/*
62 * If non-NULL, this gets called when the kernel terminates.
63 * This is done like this so rtas_flash can be a module.
64 */
65void (*rtas_flash_term_hook)(int);
66EXPORT_SYMBOL(rtas_flash_term_hook);
67
68/* RTAS use home made raw locking instead of spin_lock_irqsave
69 * because those can be called from within really nasty contexts
70 * such as having the timebase stopped which would lockup with
71 * normal locks and spinlock debugging enabled
72 */
73static unsigned long lock_rtas(void)
74{
75 unsigned long flags;
76
77 local_irq_save(flags);
78 preempt_disable();
79 arch_spin_lock(&rtas.lock);
80 return flags;
81}
82
83static void unlock_rtas(unsigned long flags)
84{
85 arch_spin_unlock(&rtas.lock);
86 local_irq_restore(flags);
87 preempt_enable();
88}
89
90/*
91 * call_rtas_display_status and call_rtas_display_status_delay
92 * are designed only for very early low-level debugging, which
93 * is why the token is hard-coded to 10.
94 */
95static void call_rtas_display_status(unsigned char c)
96{
97 unsigned long s;
98
99 if (!rtas.base)
100 return;
101
102 s = lock_rtas();
103 rtas_call_unlocked(&rtas.args, 10, 1, 1, NULL, c);
104 unlock_rtas(s);
105}
106
107static void call_rtas_display_status_delay(char c)
108{
109 static int pending_newline = 0; /* did last write end with unprinted newline? */
110 static int width = 16;
111
112 if (c == '\n') {
113 while (width-- > 0)
114 call_rtas_display_status(' ');
115 width = 16;
116 mdelay(500);
117 pending_newline = 1;
118 } else {
119 if (pending_newline) {
120 call_rtas_display_status('\r');
121 call_rtas_display_status('\n');
122 }
123 pending_newline = 0;
124 if (width--) {
125 call_rtas_display_status(c);
126 udelay(10000);
127 }
128 }
129}
130
131void __init udbg_init_rtas_panel(void)
132{
133 udbg_putc = call_rtas_display_status_delay;
134}
135
136#ifdef CONFIG_UDBG_RTAS_CONSOLE
137
138/* If you think you're dying before early_init_dt_scan_rtas() does its
139 * work, you can hard code the token values for your firmware here and
140 * hardcode rtas.base/entry etc.
141 */
142static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
143static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
144
145static void udbg_rtascon_putc(char c)
146{
147 int tries;
148
149 if (!rtas.base)
150 return;
151
152 /* Add CRs before LFs */
153 if (c == '\n')
154 udbg_rtascon_putc('\r');
155
156 /* if there is more than one character to be displayed, wait a bit */
157 for (tries = 0; tries < 16; tries++) {
158 if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
159 break;
160 udelay(1000);
161 }
162}
163
164static int udbg_rtascon_getc_poll(void)
165{
166 int c;
167
168 if (!rtas.base)
169 return -1;
170
171 if (rtas_call(rtas_getchar_token, 0, 2, &c))
172 return -1;
173
174 return c;
175}
176
177static int udbg_rtascon_getc(void)
178{
179 int c;
180
181 while ((c = udbg_rtascon_getc_poll()) == -1)
182 ;
183
184 return c;
185}
186
187
188void __init udbg_init_rtas_console(void)
189{
190 udbg_putc = udbg_rtascon_putc;
191 udbg_getc = udbg_rtascon_getc;
192 udbg_getc_poll = udbg_rtascon_getc_poll;
193}
194#endif /* CONFIG_UDBG_RTAS_CONSOLE */
195
196void rtas_progress(char *s, unsigned short hex)
197{
198 struct device_node *root;
199 int width;
200 const __be32 *p;
201 char *os;
202 static int display_character, set_indicator;
203 static int display_width, display_lines, form_feed;
204 static const int *row_width;
205 static DEFINE_SPINLOCK(progress_lock);
206 static int current_line;
207 static int pending_newline = 0; /* did last write end with unprinted newline? */
208
209 if (!rtas.base)
210 return;
211
212 if (display_width == 0) {
213 display_width = 0x10;
214 if ((root = of_find_node_by_path("/rtas"))) {
215 if ((p = of_get_property(root,
216 "ibm,display-line-length", NULL)))
217 display_width = be32_to_cpu(*p);
218 if ((p = of_get_property(root,
219 "ibm,form-feed", NULL)))
220 form_feed = be32_to_cpu(*p);
221 if ((p = of_get_property(root,
222 "ibm,display-number-of-lines", NULL)))
223 display_lines = be32_to_cpu(*p);
224 row_width = of_get_property(root,
225 "ibm,display-truncation-length", NULL);
226 of_node_put(root);
227 }
228 display_character = rtas_token("display-character");
229 set_indicator = rtas_token("set-indicator");
230 }
231
232 if (display_character == RTAS_UNKNOWN_SERVICE) {
233 /* use hex display if available */
234 if (set_indicator != RTAS_UNKNOWN_SERVICE)
235 rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
236 return;
237 }
238
239 spin_lock(&progress_lock);
240
241 /*
242 * Last write ended with newline, but we didn't print it since
243 * it would just clear the bottom line of output. Print it now
244 * instead.
245 *
246 * If no newline is pending and form feed is supported, clear the
247 * display with a form feed; otherwise, print a CR to start output
248 * at the beginning of the line.
249 */
250 if (pending_newline) {
251 rtas_call(display_character, 1, 1, NULL, '\r');
252 rtas_call(display_character, 1, 1, NULL, '\n');
253 pending_newline = 0;
254 } else {
255 current_line = 0;
256 if (form_feed)
257 rtas_call(display_character, 1, 1, NULL,
258 (char)form_feed);
259 else
260 rtas_call(display_character, 1, 1, NULL, '\r');
261 }
262
263 if (row_width)
264 width = row_width[current_line];
265 else
266 width = display_width;
267 os = s;
268 while (*os) {
269 if (*os == '\n' || *os == '\r') {
270 /* If newline is the last character, save it
271 * until next call to avoid bumping up the
272 * display output.
273 */
274 if (*os == '\n' && !os[1]) {
275 pending_newline = 1;
276 current_line++;
277 if (current_line > display_lines-1)
278 current_line = display_lines-1;
279 spin_unlock(&progress_lock);
280 return;
281 }
282
283 /* RTAS wants CR-LF, not just LF */
284
285 if (*os == '\n') {
286 rtas_call(display_character, 1, 1, NULL, '\r');
287 rtas_call(display_character, 1, 1, NULL, '\n');
288 } else {
289 /* CR might be used to re-draw a line, so we'll
290 * leave it alone and not add LF.
291 */
292 rtas_call(display_character, 1, 1, NULL, *os);
293 }
294
295 if (row_width)
296 width = row_width[current_line];
297 else
298 width = display_width;
299 } else {
300 width--;
301 rtas_call(display_character, 1, 1, NULL, *os);
302 }
303
304 os++;
305
306 /* if we overwrite the screen length */
307 if (width <= 0)
308 while ((*os != 0) && (*os != '\n') && (*os != '\r'))
309 os++;
310 }
311
312 spin_unlock(&progress_lock);
313}
314EXPORT_SYMBOL(rtas_progress); /* needed by rtas_flash module */
315
316int rtas_token(const char *service)
317{
318 const __be32 *tokp;
319 if (rtas.dev == NULL)
320 return RTAS_UNKNOWN_SERVICE;
321 tokp = of_get_property(rtas.dev, service, NULL);
322 return tokp ? be32_to_cpu(*tokp) : RTAS_UNKNOWN_SERVICE;
323}
324EXPORT_SYMBOL(rtas_token);
325
326int rtas_service_present(const char *service)
327{
328 return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
329}
330EXPORT_SYMBOL(rtas_service_present);
331
332#ifdef CONFIG_RTAS_ERROR_LOGGING
333/*
334 * Return the firmware-specified size of the error log buffer
335 * for all rtas calls that require an error buffer argument.
336 * This includes 'check-exception' and 'rtas-last-error'.
337 */
338int rtas_get_error_log_max(void)
339{
340 static int rtas_error_log_max;
341 if (rtas_error_log_max)
342 return rtas_error_log_max;
343
344 rtas_error_log_max = rtas_token ("rtas-error-log-max");
345 if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
346 (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
347 printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
348 rtas_error_log_max);
349 rtas_error_log_max = RTAS_ERROR_LOG_MAX;
350 }
351 return rtas_error_log_max;
352}
353EXPORT_SYMBOL(rtas_get_error_log_max);
354
355
356static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
357static int rtas_last_error_token;
358
359/** Return a copy of the detailed error text associated with the
360 * most recent failed call to rtas. Because the error text
361 * might go stale if there are any other intervening rtas calls,
362 * this routine must be called atomically with whatever produced
363 * the error (i.e. with rtas.lock still held from the previous call).
364 */
365static char *__fetch_rtas_last_error(char *altbuf)
366{
367 struct rtas_args err_args, save_args;
368 u32 bufsz;
369 char *buf = NULL;
370
371 if (rtas_last_error_token == -1)
372 return NULL;
373
374 bufsz = rtas_get_error_log_max();
375
376 err_args.token = cpu_to_be32(rtas_last_error_token);
377 err_args.nargs = cpu_to_be32(2);
378 err_args.nret = cpu_to_be32(1);
379 err_args.args[0] = cpu_to_be32(__pa(rtas_err_buf));
380 err_args.args[1] = cpu_to_be32(bufsz);
381 err_args.args[2] = 0;
382
383 save_args = rtas.args;
384 rtas.args = err_args;
385
386 enter_rtas(__pa(&rtas.args));
387
388 err_args = rtas.args;
389 rtas.args = save_args;
390
391 /* Log the error in the unlikely case that there was one. */
392 if (unlikely(err_args.args[2] == 0)) {
393 if (altbuf) {
394 buf = altbuf;
395 } else {
396 buf = rtas_err_buf;
397 if (slab_is_available())
398 buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
399 }
400 if (buf)
401 memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
402 }
403
404 return buf;
405}
406
407#define get_errorlog_buffer() kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
408
409#else /* CONFIG_RTAS_ERROR_LOGGING */
410#define __fetch_rtas_last_error(x) NULL
411#define get_errorlog_buffer() NULL
412#endif
413
414
415static void
416va_rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret,
417 va_list list)
418{
419 int i;
420
421 args->token = cpu_to_be32(token);
422 args->nargs = cpu_to_be32(nargs);
423 args->nret = cpu_to_be32(nret);
424 args->rets = &(args->args[nargs]);
425
426 for (i = 0; i < nargs; ++i)
427 args->args[i] = cpu_to_be32(va_arg(list, __u32));
428
429 for (i = 0; i < nret; ++i)
430 args->rets[i] = 0;
431
432 enter_rtas(__pa(args));
433}
434
435void rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret, ...)
436{
437 va_list list;
438
439 va_start(list, nret);
440 va_rtas_call_unlocked(args, token, nargs, nret, list);
441 va_end(list);
442}
443
444int rtas_call(int token, int nargs, int nret, int *outputs, ...)
445{
446 va_list list;
447 int i;
448 unsigned long s;
449 struct rtas_args *rtas_args;
450 char *buff_copy = NULL;
451 int ret;
452
453 if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
454 return -1;
455
456 s = lock_rtas();
457
458 /* We use the global rtas args buffer */
459 rtas_args = &rtas.args;
460
461 va_start(list, outputs);
462 va_rtas_call_unlocked(rtas_args, token, nargs, nret, list);
463 va_end(list);
464
465 /* A -1 return code indicates that the last command couldn't
466 be completed due to a hardware error. */
467 if (be32_to_cpu(rtas_args->rets[0]) == -1)
468 buff_copy = __fetch_rtas_last_error(NULL);
469
470 if (nret > 1 && outputs != NULL)
471 for (i = 0; i < nret-1; ++i)
472 outputs[i] = be32_to_cpu(rtas_args->rets[i+1]);
473 ret = (nret > 0)? be32_to_cpu(rtas_args->rets[0]): 0;
474
475 unlock_rtas(s);
476
477 if (buff_copy) {
478 log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
479 if (slab_is_available())
480 kfree(buff_copy);
481 }
482 return ret;
483}
484EXPORT_SYMBOL(rtas_call);
485
486/* For RTAS_BUSY (-2), delay for 1 millisecond. For an extended busy status
487 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
488 */
489unsigned int rtas_busy_delay_time(int status)
490{
491 int order;
492 unsigned int ms = 0;
493
494 if (status == RTAS_BUSY) {
495 ms = 1;
496 } else if (status >= RTAS_EXTENDED_DELAY_MIN &&
497 status <= RTAS_EXTENDED_DELAY_MAX) {
498 order = status - RTAS_EXTENDED_DELAY_MIN;
499 for (ms = 1; order > 0; order--)
500 ms *= 10;
501 }
502
503 return ms;
504}
505EXPORT_SYMBOL(rtas_busy_delay_time);
506
507/* For an RTAS busy status code, perform the hinted delay. */
508unsigned int rtas_busy_delay(int status)
509{
510 unsigned int ms;
511
512 might_sleep();
513 ms = rtas_busy_delay_time(status);
514 if (ms && need_resched())
515 msleep(ms);
516
517 return ms;
518}
519EXPORT_SYMBOL(rtas_busy_delay);
520
521static int rtas_error_rc(int rtas_rc)
522{
523 int rc;
524
525 switch (rtas_rc) {
526 case -1: /* Hardware Error */
527 rc = -EIO;
528 break;
529 case -3: /* Bad indicator/domain/etc */
530 rc = -EINVAL;
531 break;
532 case -9000: /* Isolation error */
533 rc = -EFAULT;
534 break;
535 case -9001: /* Outstanding TCE/PTE */
536 rc = -EEXIST;
537 break;
538 case -9002: /* No usable slot */
539 rc = -ENODEV;
540 break;
541 default:
542 printk(KERN_ERR "%s: unexpected RTAS error %d\n",
543 __func__, rtas_rc);
544 rc = -ERANGE;
545 break;
546 }
547 return rc;
548}
549
550int rtas_get_power_level(int powerdomain, int *level)
551{
552 int token = rtas_token("get-power-level");
553 int rc;
554
555 if (token == RTAS_UNKNOWN_SERVICE)
556 return -ENOENT;
557
558 while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
559 udelay(1);
560
561 if (rc < 0)
562 return rtas_error_rc(rc);
563 return rc;
564}
565EXPORT_SYMBOL(rtas_get_power_level);
566
567int rtas_set_power_level(int powerdomain, int level, int *setlevel)
568{
569 int token = rtas_token("set-power-level");
570 int rc;
571
572 if (token == RTAS_UNKNOWN_SERVICE)
573 return -ENOENT;
574
575 do {
576 rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
577 } while (rtas_busy_delay(rc));
578
579 if (rc < 0)
580 return rtas_error_rc(rc);
581 return rc;
582}
583EXPORT_SYMBOL(rtas_set_power_level);
584
585int rtas_get_sensor(int sensor, int index, int *state)
586{
587 int token = rtas_token("get-sensor-state");
588 int rc;
589
590 if (token == RTAS_UNKNOWN_SERVICE)
591 return -ENOENT;
592
593 do {
594 rc = rtas_call(token, 2, 2, state, sensor, index);
595 } while (rtas_busy_delay(rc));
596
597 if (rc < 0)
598 return rtas_error_rc(rc);
599 return rc;
600}
601EXPORT_SYMBOL(rtas_get_sensor);
602
603int rtas_get_sensor_fast(int sensor, int index, int *state)
604{
605 int token = rtas_token("get-sensor-state");
606 int rc;
607
608 if (token == RTAS_UNKNOWN_SERVICE)
609 return -ENOENT;
610
611 rc = rtas_call(token, 2, 2, state, sensor, index);
612 WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
613 rc <= RTAS_EXTENDED_DELAY_MAX));
614
615 if (rc < 0)
616 return rtas_error_rc(rc);
617 return rc;
618}
619
620bool rtas_indicator_present(int token, int *maxindex)
621{
622 int proplen, count, i;
623 const struct indicator_elem {
624 __be32 token;
625 __be32 maxindex;
626 } *indicators;
627
628 indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
629 if (!indicators)
630 return false;
631
632 count = proplen / sizeof(struct indicator_elem);
633
634 for (i = 0; i < count; i++) {
635 if (__be32_to_cpu(indicators[i].token) != token)
636 continue;
637 if (maxindex)
638 *maxindex = __be32_to_cpu(indicators[i].maxindex);
639 return true;
640 }
641
642 return false;
643}
644EXPORT_SYMBOL(rtas_indicator_present);
645
646int rtas_set_indicator(int indicator, int index, int new_value)
647{
648 int token = rtas_token("set-indicator");
649 int rc;
650
651 if (token == RTAS_UNKNOWN_SERVICE)
652 return -ENOENT;
653
654 do {
655 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
656 } while (rtas_busy_delay(rc));
657
658 if (rc < 0)
659 return rtas_error_rc(rc);
660 return rc;
661}
662EXPORT_SYMBOL(rtas_set_indicator);
663
664/*
665 * Ignoring RTAS extended delay
666 */
667int rtas_set_indicator_fast(int indicator, int index, int new_value)
668{
669 int rc;
670 int token = rtas_token("set-indicator");
671
672 if (token == RTAS_UNKNOWN_SERVICE)
673 return -ENOENT;
674
675 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
676
677 WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
678 rc <= RTAS_EXTENDED_DELAY_MAX));
679
680 if (rc < 0)
681 return rtas_error_rc(rc);
682
683 return rc;
684}
685
686void __noreturn rtas_restart(char *cmd)
687{
688 if (rtas_flash_term_hook)
689 rtas_flash_term_hook(SYS_RESTART);
690 printk("RTAS system-reboot returned %d\n",
691 rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
692 for (;;);
693}
694
695void rtas_power_off(void)
696{
697 if (rtas_flash_term_hook)
698 rtas_flash_term_hook(SYS_POWER_OFF);
699 /* allow power on only with power button press */
700 printk("RTAS power-off returned %d\n",
701 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
702 for (;;);
703}
704
705void __noreturn rtas_halt(void)
706{
707 if (rtas_flash_term_hook)
708 rtas_flash_term_hook(SYS_HALT);
709 /* allow power on only with power button press */
710 printk("RTAS power-off returned %d\n",
711 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
712 for (;;);
713}
714
715/* Must be in the RMO region, so we place it here */
716static char rtas_os_term_buf[2048];
717
718void rtas_os_term(char *str)
719{
720 int status;
721
722 /*
723 * Firmware with the ibm,extended-os-term property is guaranteed
724 * to always return from an ibm,os-term call. Earlier versions without
725 * this property may terminate the partition which we want to avoid
726 * since it interferes with panic_timeout.
727 */
728 if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
729 RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
730 return;
731
732 snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
733
734 do {
735 status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
736 __pa(rtas_os_term_buf));
737 } while (rtas_busy_delay(status));
738
739 if (status != 0)
740 printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
741}
742
743static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
744#ifdef CONFIG_PPC_PSERIES
745static int __rtas_suspend_last_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
746{
747 u16 slb_size = mmu_slb_size;
748 int rc = H_MULTI_THREADS_ACTIVE;
749 int cpu;
750
751 slb_set_size(SLB_MIN_SIZE);
752 printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n", smp_processor_id());
753
754 while (rc == H_MULTI_THREADS_ACTIVE && !atomic_read(&data->done) &&
755 !atomic_read(&data->error))
756 rc = rtas_call(data->token, 0, 1, NULL);
757
758 if (rc || atomic_read(&data->error)) {
759 printk(KERN_DEBUG "ibm,suspend-me returned %d\n", rc);
760 slb_set_size(slb_size);
761 }
762
763 if (atomic_read(&data->error))
764 rc = atomic_read(&data->error);
765
766 atomic_set(&data->error, rc);
767 pSeries_coalesce_init();
768
769 if (wake_when_done) {
770 atomic_set(&data->done, 1);
771
772 for_each_online_cpu(cpu)
773 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
774 }
775
776 if (atomic_dec_return(&data->working) == 0)
777 complete(data->complete);
778
779 return rc;
780}
781
782int rtas_suspend_last_cpu(struct rtas_suspend_me_data *data)
783{
784 atomic_inc(&data->working);
785 return __rtas_suspend_last_cpu(data, 0);
786}
787
788static int __rtas_suspend_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
789{
790 long rc = H_SUCCESS;
791 unsigned long msr_save;
792 int cpu;
793
794 atomic_inc(&data->working);
795
796 /* really need to ensure MSR.EE is off for H_JOIN */
797 msr_save = mfmsr();
798 mtmsr(msr_save & ~(MSR_EE));
799
800 while (rc == H_SUCCESS && !atomic_read(&data->done) && !atomic_read(&data->error))
801 rc = plpar_hcall_norets(H_JOIN);
802
803 mtmsr(msr_save);
804
805 if (rc == H_SUCCESS) {
806 /* This cpu was prodded and the suspend is complete. */
807 goto out;
808 } else if (rc == H_CONTINUE) {
809 /* All other cpus are in H_JOIN, this cpu does
810 * the suspend.
811 */
812 return __rtas_suspend_last_cpu(data, wake_when_done);
813 } else {
814 printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
815 smp_processor_id(), rc);
816 atomic_set(&data->error, rc);
817 }
818
819 if (wake_when_done) {
820 atomic_set(&data->done, 1);
821
822 /* This cpu did the suspend or got an error; in either case,
823 * we need to prod all other other cpus out of join state.
824 * Extra prods are harmless.
825 */
826 for_each_online_cpu(cpu)
827 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
828 }
829out:
830 if (atomic_dec_return(&data->working) == 0)
831 complete(data->complete);
832 return rc;
833}
834
835int rtas_suspend_cpu(struct rtas_suspend_me_data *data)
836{
837 return __rtas_suspend_cpu(data, 0);
838}
839
840static void rtas_percpu_suspend_me(void *info)
841{
842 __rtas_suspend_cpu((struct rtas_suspend_me_data *)info, 1);
843}
844
845enum rtas_cpu_state {
846 DOWN,
847 UP,
848};
849
850#ifndef CONFIG_SMP
851static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
852 cpumask_var_t cpus)
853{
854 if (!cpumask_empty(cpus)) {
855 cpumask_clear(cpus);
856 return -EINVAL;
857 } else
858 return 0;
859}
860#else
861/* On return cpumask will be altered to indicate CPUs changed.
862 * CPUs with states changed will be set in the mask,
863 * CPUs with status unchanged will be unset in the mask. */
864static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
865 cpumask_var_t cpus)
866{
867 int cpu;
868 int cpuret = 0;
869 int ret = 0;
870
871 if (cpumask_empty(cpus))
872 return 0;
873
874 for_each_cpu(cpu, cpus) {
875 struct device *dev = get_cpu_device(cpu);
876
877 switch (state) {
878 case DOWN:
879 cpuret = device_offline(dev);
880 break;
881 case UP:
882 cpuret = device_online(dev);
883 break;
884 }
885 if (cpuret < 0) {
886 pr_debug("%s: cpu_%s for cpu#%d returned %d.\n",
887 __func__,
888 ((state == UP) ? "up" : "down"),
889 cpu, cpuret);
890 if (!ret)
891 ret = cpuret;
892 if (state == UP) {
893 /* clear bits for unchanged cpus, return */
894 cpumask_shift_right(cpus, cpus, cpu);
895 cpumask_shift_left(cpus, cpus, cpu);
896 break;
897 } else {
898 /* clear bit for unchanged cpu, continue */
899 cpumask_clear_cpu(cpu, cpus);
900 }
901 }
902 cond_resched();
903 }
904
905 return ret;
906}
907#endif
908
909int rtas_online_cpus_mask(cpumask_var_t cpus)
910{
911 int ret;
912
913 ret = rtas_cpu_state_change_mask(UP, cpus);
914
915 if (ret) {
916 cpumask_var_t tmp_mask;
917
918 if (!alloc_cpumask_var(&tmp_mask, GFP_KERNEL))
919 return ret;
920
921 /* Use tmp_mask to preserve cpus mask from first failure */
922 cpumask_copy(tmp_mask, cpus);
923 rtas_offline_cpus_mask(tmp_mask);
924 free_cpumask_var(tmp_mask);
925 }
926
927 return ret;
928}
929
930int rtas_offline_cpus_mask(cpumask_var_t cpus)
931{
932 return rtas_cpu_state_change_mask(DOWN, cpus);
933}
934
935int rtas_ibm_suspend_me(u64 handle)
936{
937 long state;
938 long rc;
939 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
940 struct rtas_suspend_me_data data;
941 DECLARE_COMPLETION_ONSTACK(done);
942 cpumask_var_t offline_mask;
943 int cpuret;
944
945 if (!rtas_service_present("ibm,suspend-me"))
946 return -ENOSYS;
947
948 /* Make sure the state is valid */
949 rc = plpar_hcall(H_VASI_STATE, retbuf, handle);
950
951 state = retbuf[0];
952
953 if (rc) {
954 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
955 return rc;
956 } else if (state == H_VASI_ENABLED) {
957 return -EAGAIN;
958 } else if (state != H_VASI_SUSPENDING) {
959 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
960 state);
961 return -EIO;
962 }
963
964 if (!alloc_cpumask_var(&offline_mask, GFP_KERNEL))
965 return -ENOMEM;
966
967 atomic_set(&data.working, 0);
968 atomic_set(&data.done, 0);
969 atomic_set(&data.error, 0);
970 data.token = rtas_token("ibm,suspend-me");
971 data.complete = &done;
972
973 lock_device_hotplug();
974
975 /* All present CPUs must be online */
976 cpumask_andnot(offline_mask, cpu_present_mask, cpu_online_mask);
977 cpuret = rtas_online_cpus_mask(offline_mask);
978 if (cpuret) {
979 pr_err("%s: Could not bring present CPUs online.\n", __func__);
980 atomic_set(&data.error, cpuret);
981 goto out;
982 }
983
984 cpu_hotplug_disable();
985
986 /* Check if we raced with a CPU-Offline Operation */
987 if (!cpumask_equal(cpu_present_mask, cpu_online_mask)) {
988 pr_info("%s: Raced against a concurrent CPU-Offline\n", __func__);
989 atomic_set(&data.error, -EAGAIN);
990 goto out_hotplug_enable;
991 }
992
993 /* Call function on all CPUs. One of us will make the
994 * rtas call
995 */
996 on_each_cpu(rtas_percpu_suspend_me, &data, 0);
997
998 wait_for_completion(&done);
999
1000 if (atomic_read(&data.error) != 0)
1001 printk(KERN_ERR "Error doing global join\n");
1002
1003out_hotplug_enable:
1004 cpu_hotplug_enable();
1005
1006 /* Take down CPUs not online prior to suspend */
1007 cpuret = rtas_offline_cpus_mask(offline_mask);
1008 if (cpuret)
1009 pr_warn("%s: Could not restore CPUs to offline state.\n",
1010 __func__);
1011
1012out:
1013 unlock_device_hotplug();
1014 free_cpumask_var(offline_mask);
1015 return atomic_read(&data.error);
1016}
1017#else /* CONFIG_PPC_PSERIES */
1018int rtas_ibm_suspend_me(u64 handle)
1019{
1020 return -ENOSYS;
1021}
1022#endif
1023
1024/**
1025 * Find a specific pseries error log in an RTAS extended event log.
1026 * @log: RTAS error/event log
1027 * @section_id: two character section identifier
1028 *
1029 * Returns a pointer to the specified errorlog or NULL if not found.
1030 */
1031struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
1032 uint16_t section_id)
1033{
1034 struct rtas_ext_event_log_v6 *ext_log =
1035 (struct rtas_ext_event_log_v6 *)log->buffer;
1036 struct pseries_errorlog *sect;
1037 unsigned char *p, *log_end;
1038 uint32_t ext_log_length = rtas_error_extended_log_length(log);
1039 uint8_t log_format = rtas_ext_event_log_format(ext_log);
1040 uint32_t company_id = rtas_ext_event_company_id(ext_log);
1041
1042 /* Check that we understand the format */
1043 if (ext_log_length < sizeof(struct rtas_ext_event_log_v6) ||
1044 log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
1045 company_id != RTAS_V6EXT_COMPANY_ID_IBM)
1046 return NULL;
1047
1048 log_end = log->buffer + ext_log_length;
1049 p = ext_log->vendor_log;
1050
1051 while (p < log_end) {
1052 sect = (struct pseries_errorlog *)p;
1053 if (pseries_errorlog_id(sect) == section_id)
1054 return sect;
1055 p += pseries_errorlog_length(sect);
1056 }
1057
1058 return NULL;
1059}
1060
1061/* We assume to be passed big endian arguments */
1062SYSCALL_DEFINE1(rtas, struct rtas_args __user *, uargs)
1063{
1064 struct rtas_args args;
1065 unsigned long flags;
1066 char *buff_copy, *errbuf = NULL;
1067 int nargs, nret, token;
1068
1069 if (!capable(CAP_SYS_ADMIN))
1070 return -EPERM;
1071
1072 if (!rtas.entry)
1073 return -EINVAL;
1074
1075 if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
1076 return -EFAULT;
1077
1078 nargs = be32_to_cpu(args.nargs);
1079 nret = be32_to_cpu(args.nret);
1080 token = be32_to_cpu(args.token);
1081
1082 if (nargs >= ARRAY_SIZE(args.args)
1083 || nret > ARRAY_SIZE(args.args)
1084 || nargs + nret > ARRAY_SIZE(args.args))
1085 return -EINVAL;
1086
1087 /* Copy in args. */
1088 if (copy_from_user(args.args, uargs->args,
1089 nargs * sizeof(rtas_arg_t)) != 0)
1090 return -EFAULT;
1091
1092 if (token == RTAS_UNKNOWN_SERVICE)
1093 return -EINVAL;
1094
1095 args.rets = &args.args[nargs];
1096 memset(args.rets, 0, nret * sizeof(rtas_arg_t));
1097
1098 /* Need to handle ibm,suspend_me call specially */
1099 if (token == ibm_suspend_me_token) {
1100
1101 /*
1102 * rtas_ibm_suspend_me assumes the streamid handle is in cpu
1103 * endian, or at least the hcall within it requires it.
1104 */
1105 int rc = 0;
1106 u64 handle = ((u64)be32_to_cpu(args.args[0]) << 32)
1107 | be32_to_cpu(args.args[1]);
1108 rc = rtas_ibm_suspend_me(handle);
1109 if (rc == -EAGAIN)
1110 args.rets[0] = cpu_to_be32(RTAS_NOT_SUSPENDABLE);
1111 else if (rc == -EIO)
1112 args.rets[0] = cpu_to_be32(-1);
1113 else if (rc)
1114 return rc;
1115 goto copy_return;
1116 }
1117
1118 buff_copy = get_errorlog_buffer();
1119
1120 flags = lock_rtas();
1121
1122 rtas.args = args;
1123 enter_rtas(__pa(&rtas.args));
1124 args = rtas.args;
1125
1126 /* A -1 return code indicates that the last command couldn't
1127 be completed due to a hardware error. */
1128 if (be32_to_cpu(args.rets[0]) == -1)
1129 errbuf = __fetch_rtas_last_error(buff_copy);
1130
1131 unlock_rtas(flags);
1132
1133 if (buff_copy) {
1134 if (errbuf)
1135 log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
1136 kfree(buff_copy);
1137 }
1138
1139 copy_return:
1140 /* Copy out args. */
1141 if (copy_to_user(uargs->args + nargs,
1142 args.args + nargs,
1143 nret * sizeof(rtas_arg_t)) != 0)
1144 return -EFAULT;
1145
1146 return 0;
1147}
1148
1149/*
1150 * Call early during boot, before mem init, to retrieve the RTAS
1151 * information from the device-tree and allocate the RMO buffer for userland
1152 * accesses.
1153 */
1154void __init rtas_initialize(void)
1155{
1156 unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
1157 u32 base, size, entry;
1158 int no_base, no_size, no_entry;
1159
1160 /* Get RTAS dev node and fill up our "rtas" structure with infos
1161 * about it.
1162 */
1163 rtas.dev = of_find_node_by_name(NULL, "rtas");
1164 if (!rtas.dev)
1165 return;
1166
1167 no_base = of_property_read_u32(rtas.dev, "linux,rtas-base", &base);
1168 no_size = of_property_read_u32(rtas.dev, "rtas-size", &size);
1169 if (no_base || no_size) {
1170 of_node_put(rtas.dev);
1171 rtas.dev = NULL;
1172 return;
1173 }
1174
1175 rtas.base = base;
1176 rtas.size = size;
1177 no_entry = of_property_read_u32(rtas.dev, "linux,rtas-entry", &entry);
1178 rtas.entry = no_entry ? rtas.base : entry;
1179
1180 /* If RTAS was found, allocate the RMO buffer for it and look for
1181 * the stop-self token if any
1182 */
1183#ifdef CONFIG_PPC64
1184 if (firmware_has_feature(FW_FEATURE_LPAR)) {
1185 rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
1186 ibm_suspend_me_token = rtas_token("ibm,suspend-me");
1187 }
1188#endif
1189 rtas_rmo_buf = memblock_phys_alloc_range(RTAS_RMOBUF_MAX, PAGE_SIZE,
1190 0, rtas_region);
1191 if (!rtas_rmo_buf)
1192 panic("ERROR: RTAS: Failed to allocate %lx bytes below %pa\n",
1193 PAGE_SIZE, &rtas_region);
1194
1195#ifdef CONFIG_RTAS_ERROR_LOGGING
1196 rtas_last_error_token = rtas_token("rtas-last-error");
1197#endif
1198}
1199
1200int __init early_init_dt_scan_rtas(unsigned long node,
1201 const char *uname, int depth, void *data)
1202{
1203 const u32 *basep, *entryp, *sizep;
1204
1205 if (depth != 1 || strcmp(uname, "rtas") != 0)
1206 return 0;
1207
1208 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
1209 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
1210 sizep = of_get_flat_dt_prop(node, "rtas-size", NULL);
1211
1212 if (basep && entryp && sizep) {
1213 rtas.base = *basep;
1214 rtas.entry = *entryp;
1215 rtas.size = *sizep;
1216 }
1217
1218#ifdef CONFIG_UDBG_RTAS_CONSOLE
1219 basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1220 if (basep)
1221 rtas_putchar_token = *basep;
1222
1223 basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1224 if (basep)
1225 rtas_getchar_token = *basep;
1226
1227 if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1228 rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1229 udbg_init_rtas_console();
1230
1231#endif
1232
1233 /* break now */
1234 return 1;
1235}
1236
1237static arch_spinlock_t timebase_lock;
1238static u64 timebase = 0;
1239
1240void rtas_give_timebase(void)
1241{
1242 unsigned long flags;
1243
1244 local_irq_save(flags);
1245 hard_irq_disable();
1246 arch_spin_lock(&timebase_lock);
1247 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1248 timebase = get_tb();
1249 arch_spin_unlock(&timebase_lock);
1250
1251 while (timebase)
1252 barrier();
1253 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1254 local_irq_restore(flags);
1255}
1256
1257void rtas_take_timebase(void)
1258{
1259 while (!timebase)
1260 barrier();
1261 arch_spin_lock(&timebase_lock);
1262 set_tb(timebase >> 32, timebase & 0xffffffff);
1263 timebase = 0;
1264 arch_spin_unlock(&timebase_lock);
1265}