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