aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/rtas.c
blob: 4a4cb5598402731afaa5717b25607a5272bab6ec (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
/*
 *
 * Procedures for interfacing to the RTAS on CHRP machines.
 *
 * Peter Bergner, IBM	March 2001.
 * Copyright (C) 2001 IBM.
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <stdarg.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/capability.h>
#include <linux/delay.h>

#include <asm/prom.h>
#include <asm/rtas.h>
#include <asm/hvcall.h>
#include <asm/semaphore.h>
#include <asm/machdep.h>
#include <asm/firmware.h>
#include <asm/page.h>
#include <asm/param.h>
#include <asm/system.h>
#include <asm/delay.h>
#include <asm/uaccess.h>
#include <asm/lmb.h>
#include <asm/udbg.h>
#include <asm/syscalls.h>

struct rtas_t rtas = {
	.lock = SPIN_LOCK_UNLOCKED
};
EXPORT_SYMBOL(rtas);

struct rtas_suspend_me_data {
	long waiting;
	struct rtas_args *args;
};

DEFINE_SPINLOCK(rtas_data_buf_lock);
EXPORT_SYMBOL(rtas_data_buf_lock);

char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
EXPORT_SYMBOL(rtas_data_buf);

unsigned long rtas_rmo_buf;

/*
 * If non-NULL, this gets called when the kernel terminates.
 * This is done like this so rtas_flash can be a module.
 */
void (*rtas_flash_term_hook)(int);
EXPORT_SYMBOL(rtas_flash_term_hook);

/*
 * call_rtas_display_status and call_rtas_display_status_delay
 * are designed only for very early low-level debugging, which
 * is why the token is hard-coded to 10.
 */
static void call_rtas_display_status(char c)
{
	struct rtas_args *args = &rtas.args;
	unsigned long s;

	if (!rtas.base)
		return;
	spin_lock_irqsave(&rtas.lock, s);

	args->token = 10;
	args->nargs = 1;
	args->nret  = 1;
	args->rets  = (rtas_arg_t *)&(args->args[1]);
	args->args[0] = (unsigned char)c;

	enter_rtas(__pa(args));

	spin_unlock_irqrestore(&rtas.lock, s);
}

static void call_rtas_display_status_delay(char c)
{
	static int pending_newline = 0;  /* did last write end with unprinted newline? */
	static int width = 16;

	if (c == '\n') {	
		while (width-- > 0)
			call_rtas_display_status(' ');
		width = 16;
		mdelay(500);
		pending_newline = 1;
	} else {
		if (pending_newline) {
			call_rtas_display_status('\r');
			call_rtas_display_status('\n');
		} 
		pending_newline = 0;
		if (width--) {
			call_rtas_display_status(c);
			udelay(10000);
		}
	}
}

void __init udbg_init_rtas_panel(void)
{
	udbg_putc = call_rtas_display_status_delay;
}

#ifdef CONFIG_UDBG_RTAS_CONSOLE

/* If you think you're dying before early_init_dt_scan_rtas() does its
 * work, you can hard code the token values for your firmware here and
 * hardcode rtas.base/entry etc.
 */
static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;

static void udbg_rtascon_putc(char c)
{
	int tries;

	if (!rtas.base)
		return;

	/* Add CRs before LFs */
	if (c == '\n')
		udbg_rtascon_putc('\r');

	/* if there is more than one character to be displayed, wait a bit */
	for (tries = 0; tries < 16; tries++) {
		if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
			break;
		udelay(1000);
	}
}

static int udbg_rtascon_getc_poll(void)
{
	int c;

	if (!rtas.base)
		return -1;

	if (rtas_call(rtas_getchar_token, 0, 2, &c))
		return -1;

	return c;
}

static int udbg_rtascon_getc(void)
{
	int c;

	while ((c = udbg_rtascon_getc_poll()) == -1)
		;

	return c;
}


void __init udbg_init_rtas_console(void)
{
	udbg_putc = udbg_rtascon_putc;
	udbg_getc = udbg_rtascon_getc;
	udbg_getc_poll = udbg_rtascon_getc_poll;
}
#endif /* CONFIG_UDBG_RTAS_CONSOLE */

void rtas_progress(char *s, unsigned short hex)
{
	struct device_node *root;
	int width, *p;
	char *os;
	static int display_character, set_indicator;
	static int display_width, display_lines, *row_width, form_feed;
	static DEFINE_SPINLOCK(progress_lock);
	static int current_line;
	static int pending_newline = 0;  /* did last write end with unprinted newline? */

	if (!rtas.base)
		return;

	if (display_width == 0) {
		display_width = 0x10;
		if ((root = find_path_device("/rtas"))) {
			if ((p = (unsigned int *)get_property(root,
					"ibm,display-line-length", NULL)))
				display_width = *p;
			if ((p = (unsigned int *)get_property(root,
					"ibm,form-feed", NULL)))
				form_feed = *p;
			if ((p = (unsigned int *)get_property(root,
					"ibm,display-number-of-lines", NULL)))
				display_lines = *p;
			row_width = (unsigned int *)get_property(root,
					"ibm,display-truncation-length", NULL);
		}
		display_character = rtas_token("display-character");
		set_indicator = rtas_token("set-indicator");
	}

	if (display_character == RTAS_UNKNOWN_SERVICE) {
		/* use hex display if available */
		if (set_indicator != RTAS_UNKNOWN_SERVICE)
			rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
		return;
	}

	spin_lock(&progress_lock);

	/*
	 * Last write ended with newline, but we didn't print it since
	 * it would just clear the bottom line of output. Print it now
	 * instead.
	 *
	 * If no newline is pending and form feed is supported, clear the
	 * display with a form feed; otherwise, print a CR to start output
	 * at the beginning of the line.
	 */
	if (pending_newline) {
		rtas_call(display_character, 1, 1, NULL, '\r');
		rtas_call(display_character, 1, 1, NULL, '\n');
		pending_newline = 0;
	} else {
		current_line = 0;
		if (form_feed)
			rtas_call(display_character, 1, 1, NULL,
				  (char)form_feed);
		else
			rtas_call(display_character, 1, 1, NULL, '\r');
	}
 
	if (row_width)
		width = row_width[current_line];
	else
		width = display_width;
	os = s;
	while (*os) {
		if (*os == '\n' || *os == '\r') {
			/* If newline is the last character, save it
			 * until next call to avoid bumping up the
			 * display output.
			 */
			if (*os == '\n' && !os[1]) {
				pending_newline = 1;
				current_line++;
				if (current_line > display_lines-1)
					current_line = display_lines-1;
				spin_unlock(&progress_lock);
				return;
			}
 
			/* RTAS wants CR-LF, not just LF */
 
			if (*os == '\n') {
				rtas_call(display_character, 1, 1, NULL, '\r');
				rtas_call(display_character, 1, 1, NULL, '\n');
			} else {
				/* CR might be used to re-draw a line, so we'll
				 * leave it alone and not add LF.
				 */
				rtas_call(display_character, 1, 1, NULL, *os);
			}
 
			if (row_width)
				width = row_width[current_line];
			else
				width = display_width;
		} else {
			width--;
			rtas_call(display_character, 1, 1, NULL, *os);
		}
 
		os++;
 
		/* if we overwrite the screen length */
		if (width <= 0)
			while ((*os != 0) && (*os != '\n') && (*os != '\r'))
				os++;
	}
 
	spin_unlock(&progress_lock);
}
EXPORT_SYMBOL(rtas_progress);		/* needed by rtas_flash module */

int rtas_token(const char *service)
{
	int *tokp;
	if (rtas.dev == NULL)
		return RTAS_UNKNOWN_SERVICE;
	tokp = (int *) get_property(rtas.dev, service, NULL);
	return tokp ? *tokp : RTAS_UNKNOWN_SERVICE;
}
EXPORT_SYMBOL(rtas_token);

#ifdef CONFIG_RTAS_ERROR_LOGGING
/*
 * Return the firmware-specified size of the error log buffer
 *  for all rtas calls that require an error buffer argument.
 *  This includes 'check-exception' and 'rtas-last-error'.
 */
int rtas_get_error_log_max(void)
{
	static int rtas_error_log_max;
	if (rtas_error_log_max)
		return rtas_error_log_max;

	rtas_error_log_max = rtas_token ("rtas-error-log-max");
	if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
	    (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
		printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
			rtas_error_log_max);
		rtas_error_log_max = RTAS_ERROR_LOG_MAX;
	}
	return rtas_error_log_max;
}
EXPORT_SYMBOL(rtas_get_error_log_max);


char rtas_err_buf[RTAS_ERROR_LOG_MAX];
int rtas_last_error_token;

/** Return a copy of the detailed error text associated with the
 *  most recent failed call to rtas.  Because the error text
 *  might go stale if there are any other intervening rtas calls,
 *  this routine must be called atomically with whatever produced
 *  the error (i.e. with rtas.lock still held from the previous call).
 */
static char *__fetch_rtas_last_error(char *altbuf)
{
	struct rtas_args err_args, save_args;
	u32 bufsz;
	char *buf = NULL;

	if (rtas_last_error_token == -1)
		return NULL;

	bufsz = rtas_get_error_log_max();

	err_args.token = rtas_last_error_token;
	err_args.nargs = 2;
	err_args.nret = 1;
	err_args.args[0] = (rtas_arg_t)__pa(rtas_err_buf);
	err_args.args[1] = bufsz;
	err_args.args[2] = 0;

	save_args = rtas.args;
	rtas.args = err_args;

	enter_rtas(__pa(&rtas.args));

	err_args = rtas.args;
	rtas.args = save_args;

	/* Log the error in the unlikely case that there was one. */
	if (unlikely(err_args.args[2] == 0)) {
		if (altbuf) {
			buf = altbuf;
		} else {
			buf = rtas_err_buf;
			if (mem_init_done)
				buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
		}
		if (buf)
			memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
	}

	return buf;
}

#define get_errorlog_buffer()	kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)

#else /* CONFIG_RTAS_ERROR_LOGGING */
#define __fetch_rtas_last_error(x)	NULL
#define get_errorlog_buffer()		NULL
#endif

int rtas_call(int token, int nargs, int nret, int *outputs, ...)
{
	va_list list;
	int i;
	unsigned long s;
	struct rtas_args *rtas_args;
	char *buff_copy = NULL;
	int ret;

	if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
		return -1;

	/* Gotta do something different here, use global lock for now... */
	spin_lock_irqsave(&rtas.lock, s);
	rtas_args = &rtas.args;

	rtas_args->token = token;
	rtas_args->nargs = nargs;
	rtas_args->nret  = nret;
	rtas_args->rets  = (rtas_arg_t *)&(rtas_args->args[nargs]);
	va_start(list, outputs);
	for (i = 0; i < nargs; ++i)
		rtas_args->args[i] = va_arg(list, rtas_arg_t);
	va_end(list);

	for (i = 0; i < nret; ++i)
		rtas_args->rets[i] = 0;

	enter_rtas(__pa(rtas_args));

	/* A -1 return code indicates that the last command couldn't
	   be completed due to a hardware error. */
	if (rtas_args->rets[0] == -1)
		buff_copy = __fetch_rtas_last_error(NULL);

	if (nret > 1 && outputs != NULL)
		for (i = 0; i < nret-1; ++i)
			outputs[i] = rtas_args->rets[i+1];
	ret = (nret > 0)? rtas_args->rets[0]: 0;

	/* Gotta do something different here, use global lock for now... */
	spin_unlock_irqrestore(&rtas.lock, s);

	if (buff_copy) {
		log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
		if (mem_init_done)
			kfree(buff_copy);
	}
	return ret;
}
EXPORT_SYMBOL(rtas_call);

/* For RTAS_BUSY (-2), delay for 1 millisecond.  For an extended busy status
 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
 */
unsigned int rtas_busy_delay_time(int status)
{
	int order;
	unsigned int ms = 0;

	if (status == RTAS_BUSY) {
		ms = 1;
	} else if (status >= 9900 && status <= 9905) {
		order = status - 9900;
		for (ms = 1; order > 0; order--)
			ms *= 10;
	}

	return ms;
}
EXPORT_SYMBOL(rtas_busy_delay_time);

/* For an RTAS busy status code, perform the hinted delay. */
unsigned int rtas_busy_delay(int status)
{
	unsigned int ms;

	might_sleep();
	ms = rtas_busy_delay_time(status);
	if (ms)
		msleep(ms);

	return ms;
}
EXPORT_SYMBOL(rtas_busy_delay);

int rtas_error_rc(int rtas_rc)
{
	int rc;

	switch (rtas_rc) {
		case -1: 		/* Hardware Error */
			rc = -EIO;
			break;
		case -3:		/* Bad indicator/domain/etc */
			rc = -EINVAL;
			break;
		case -9000:		/* Isolation error */
			rc = -EFAULT;
			break;
		case -9001:		/* Outstanding TCE/PTE */
			rc = -EEXIST;
			break;
		case -9002:		/* No usable slot */
			rc = -ENODEV;
			break;
		default:
			printk(KERN_ERR "%s: unexpected RTAS error %d\n",
					__FUNCTION__, rtas_rc);
			rc = -ERANGE;
			break;
	}
	return rc;
}

int rtas_get_power_level(int powerdomain, int *level)
{
	int token = rtas_token("get-power-level");
	int rc;

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
		udelay(1);

	if (rc < 0)
		return rtas_error_rc(rc);
	return rc;
}
EXPORT_SYMBOL(rtas_get_power_level);

int rtas_set_power_level(int powerdomain, int level, int *setlevel)
{
	int token = rtas_token("set-power-level");
	int rc;

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	do {
		rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
	} while (rtas_busy_delay(rc));

	if (rc < 0)
		return rtas_error_rc(rc);
	return rc;
}
EXPORT_SYMBOL(rtas_set_power_level);

int rtas_get_sensor(int sensor, int index, int *state)
{
	int token = rtas_token("get-sensor-state");
	int rc;

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	do {
		rc = rtas_call(token, 2, 2, state, sensor, index);
	} while (rtas_busy_delay(rc));

	if (rc < 0)
		return rtas_error_rc(rc);
	return rc;
}
EXPORT_SYMBOL(rtas_get_sensor);

int rtas_set_indicator(int indicator, int index, int new_value)
{
	int token = rtas_token("set-indicator");
	int rc;

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	do {
		rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
	} while (rtas_busy_delay(rc));

	if (rc < 0)
		return rtas_error_rc(rc);
	return rc;
}
EXPORT_SYMBOL(rtas_set_indicator);

void rtas_restart(char *cmd)
{
	if (rtas_flash_term_hook)
		rtas_flash_term_hook(SYS_RESTART);
	printk("RTAS system-reboot returned %d\n",
	       rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
	for (;;);
}

void rtas_power_off(void)
{
	if (rtas_flash_term_hook)
		rtas_flash_term_hook(SYS_POWER_OFF);
	/* allow power on only with power button press */
	printk("RTAS power-off returned %d\n",
	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
	for (;;);
}

void rtas_halt(void)
{
	if (rtas_flash_term_hook)
		rtas_flash_term_hook(SYS_HALT);
	/* allow power on only with power button press */
	printk("RTAS power-off returned %d\n",
	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
	for (;;);
}

/* Must be in the RMO region, so we place it here */
static char rtas_os_term_buf[2048];

void rtas_os_term(char *str)
{
	int status;

	if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term"))
		return;

	snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);

	do {
		status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
				   __pa(rtas_os_term_buf));
	} while (rtas_busy_delay(status));

	if (status != 0)
		printk(KERN_EMERG "ibm,os-term call failed %d\n",
			       status);
}

static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
#ifdef CONFIG_PPC_PSERIES
static void rtas_percpu_suspend_me(void *info)
{
	int i;
	long rc;
	long flags;
	struct rtas_suspend_me_data *data =
		(struct rtas_suspend_me_data *)info;

	/*
	 * We use "waiting" to indicate our state.  As long
	 * as it is >0, we are still trying to all join up.
	 * If it goes to 0, we have successfully joined up and
	 * one thread got H_CONTINUE.  If any error happens,
	 * we set it to <0.
	 */
	local_irq_save(flags);
	do {
		rc = plpar_hcall_norets(H_JOIN);
		smp_rmb();
	} while (rc == H_SUCCESS && data->waiting > 0);
	if (rc == H_SUCCESS)
		goto out;

	if (rc == H_CONTINUE) {
		data->waiting = 0;
		data->args->args[data->args->nargs] =
			rtas_call(ibm_suspend_me_token, 0, 1, NULL);
		for_each_possible_cpu(i)
			plpar_hcall_norets(H_PROD,i);
	} else {
		data->waiting = -EBUSY;
		printk(KERN_ERR "Error on H_JOIN hypervisor call\n");
	}

out:
	local_irq_restore(flags);
	return;
}

static int rtas_ibm_suspend_me(struct rtas_args *args)
{
	int i;
	long state;
	long rc;
	unsigned long dummy;

	struct rtas_suspend_me_data data;

	/* Make sure the state is valid */
	rc = plpar_hcall(H_VASI_STATE,
			 ((u64)args->args[0] << 32) | args->args[1],
			 0, 0, 0,
			 &state, &dummy, &dummy);

	if (rc) {
		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
		return rc;
	} else if (state == H_VASI_ENABLED) {
		args->args[args->nargs] = RTAS_NOT_SUSPENDABLE;
		return 0;
	} else if (state != H_VASI_SUSPENDING) {
		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
		       state);
		args->args[args->nargs] = -1;
		return 0;
	}

	data.waiting = 1;
	data.args = args;

	/* Call function on all CPUs.  One of us will make the
	 * rtas call
	 */
	if (on_each_cpu(rtas_percpu_suspend_me, &data, 1, 0))
		data.waiting = -EINVAL;

	if (data.waiting != 0)
		printk(KERN_ERR "Error doing global join\n");

	/* Prod each CPU.  This won't hurt, and will wake
	 * anyone we successfully put to sleep with H_JOIN.
	 */
	for_each_possible_cpu(i)
		plpar_hcall_norets(H_PROD, i);

	return data.waiting;
}
#else /* CONFIG_PPC_PSERIES */
static int rtas_ibm_suspend_me(struct rtas_args *args)
{
	return -ENOSYS;
}
#endif

asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
{
	struct rtas_args args;
	unsigned long flags;
	char *buff_copy, *errbuf = NULL;
	int nargs;
	int rc;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
		return -EFAULT;

	nargs = args.nargs;
	if (nargs > ARRAY_SIZE(args.args)
	    || args.nret > ARRAY_SIZE(args.args)
	    || nargs + args.nret > ARRAY_SIZE(args.args))
		return -EINVAL;

	/* Copy in args. */
	if (copy_from_user(args.args, uargs->args,
			   nargs * sizeof(rtas_arg_t)) != 0)
		return -EFAULT;

	if (args.token == RTAS_UNKNOWN_SERVICE)
		return -EINVAL;

	/* Need to handle ibm,suspend_me call specially */
	if (args.token == ibm_suspend_me_token) {
		rc = rtas_ibm_suspend_me(&args);
		if (rc)
			return rc;
		goto copy_return;
	}

	buff_copy = get_errorlog_buffer();

	spin_lock_irqsave(&rtas.lock, flags);

	rtas.args = args;
	enter_rtas(__pa(&rtas.args));
	args = rtas.args;

	args.rets = &args.args[nargs];

	/* A -1 return code indicates that the last command couldn't
	   be completed due to a hardware error. */
	if (args.rets[0] == -1)
		errbuf = __fetch_rtas_last_error(buff_copy);

	spin_unlock_irqrestore(&rtas.lock, flags);

	if (buff_copy) {
		if (errbuf)
			log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
		kfree(buff_copy);
	}

 copy_return:
	/* Copy out args. */
	if (copy_to_user(uargs->args + nargs,
			 args.args + nargs,
			 args.nret * sizeof(rtas_arg_t)) != 0)
		return -EFAULT;

	return 0;
}

/* This version can't take the spinlock, because it never returns */

struct rtas_args rtas_stop_self_args = {
	/* The token is initialized for real in setup_system() */
	.token = RTAS_UNKNOWN_SERVICE,
	.nargs = 0,
	.nret = 1,
	.rets = &rtas_stop_self_args.args[0],
};

void rtas_stop_self(void)
{
	struct rtas_args *rtas_args = &rtas_stop_self_args;

	local_irq_disable();

	BUG_ON(rtas_args->token == RTAS_UNKNOWN_SERVICE);

	printk("cpu %u (hwid %u) Ready to die...\n",
	       smp_processor_id(), hard_smp_processor_id());
	enter_rtas(__pa(rtas_args));

	panic("Alas, I survived.\n");
}

/*
 * Call early during boot, before mem init or bootmem, to retrieve the RTAS
 * informations from the device-tree and allocate the RMO buffer for userland
 * accesses.
 */
void __init rtas_initialize(void)
{
	unsigned long rtas_region = RTAS_INSTANTIATE_MAX;

	/* Get RTAS dev node and fill up our "rtas" structure with infos
	 * about it.
	 */
	rtas.dev = of_find_node_by_name(NULL, "rtas");
	if (rtas.dev) {
		u32 *basep, *entryp;
		u32 *sizep;

		basep = (u32 *)get_property(rtas.dev, "linux,rtas-base", NULL);
		sizep = (u32 *)get_property(rtas.dev, "rtas-size", NULL);
		if (basep != NULL && sizep != NULL) {
			rtas.base = *basep;
			rtas.size = *sizep;
			entryp = (u32 *)get_property(rtas.dev, "linux,rtas-entry", NULL);
			if (entryp == NULL) /* Ugh */
				rtas.entry = rtas.base;
			else
				rtas.entry = *entryp;
		} else
			rtas.dev = NULL;
	}
	if (!rtas.dev)
		return;

	/* If RTAS was found, allocate the RMO buffer for it and look for
	 * the stop-self token if any
	 */
#ifdef CONFIG_PPC64
	if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
		rtas_region = min(lmb.rmo_size, RTAS_INSTANTIATE_MAX);
		ibm_suspend_me_token = rtas_token("ibm,suspend-me");
	}
#endif
	rtas_rmo_buf = lmb_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);

#ifdef CONFIG_HOTPLUG_CPU
	rtas_stop_self_args.token = rtas_token("stop-self");
#endif /* CONFIG_HOTPLUG_CPU */
#ifdef CONFIG_RTAS_ERROR_LOGGING
	rtas_last_error_token = rtas_token("rtas-last-error");
#endif
}

int __init early_init_dt_scan_rtas(unsigned long node,
		const char *uname, int depth, void *data)
{
	u32 *basep, *entryp, *sizep;

	if (depth != 1 || strcmp(uname, "rtas") != 0)
		return 0;

	basep  = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
	entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
	sizep  = of_get_flat_dt_prop(node, "rtas-size", NULL);

	if (basep && entryp && sizep) {
		rtas.base = *basep;
		rtas.entry = *entryp;
		rtas.size = *sizep;
	}

#ifdef CONFIG_UDBG_RTAS_CONSOLE
	basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
	if (basep)
		rtas_putchar_token = *basep;

	basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
	if (basep)
		rtas_getchar_token = *basep;
#endif

	/* break now */
	return 1;
}