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 <asm/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 #include <asm/pSeries_reconfig.h>
47
48 struct rtas_t rtas = {
49 .lock = __ARCH_SPIN_LOCK_UNLOCKED
50 };
51 EXPORT_SYMBOL(rtas);
52
53 DEFINE_SPINLOCK(rtas_data_buf_lock);
54 EXPORT_SYMBOL(rtas_data_buf_lock);
55
56 char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
57 EXPORT_SYMBOL(rtas_data_buf);
58
59 unsigned 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 */
65 void (*rtas_flash_term_hook)(int);
66 EXPORT_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 */
lock_rtas(void)73 static unsigned long lock_rtas(void)
74 {
75 unsigned long flags;
76
77 local_irq_save(flags);
78 preempt_disable();
79 arch_spin_lock_flags(&rtas.lock, flags);
80 return flags;
81 }
82
unlock_rtas(unsigned long flags)83 static 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 */
call_rtas_display_status(char c)95 static void call_rtas_display_status(char c)
96 {
97 struct rtas_args *args = &rtas.args;
98 unsigned long s;
99
100 if (!rtas.base)
101 return;
102 s = lock_rtas();
103
104 args->token = 10;
105 args->nargs = 1;
106 args->nret = 1;
107 args->rets = (rtas_arg_t *)&(args->args[1]);
108 args->args[0] = (unsigned char)c;
109
110 enter_rtas(__pa(args));
111
112 unlock_rtas(s);
113 }
114
call_rtas_display_status_delay(char c)115 static void call_rtas_display_status_delay(char c)
116 {
117 static int pending_newline = 0; /* did last write end with unprinted newline? */
118 static int width = 16;
119
120 if (c == '\n') {
121 while (width-- > 0)
122 call_rtas_display_status(' ');
123 width = 16;
124 mdelay(500);
125 pending_newline = 1;
126 } else {
127 if (pending_newline) {
128 call_rtas_display_status('\r');
129 call_rtas_display_status('\n');
130 }
131 pending_newline = 0;
132 if (width--) {
133 call_rtas_display_status(c);
134 udelay(10000);
135 }
136 }
137 }
138
udbg_init_rtas_panel(void)139 void __init udbg_init_rtas_panel(void)
140 {
141 udbg_putc = call_rtas_display_status_delay;
142 }
143
144 #ifdef CONFIG_UDBG_RTAS_CONSOLE
145
146 /* If you think you're dying before early_init_dt_scan_rtas() does its
147 * work, you can hard code the token values for your firmware here and
148 * hardcode rtas.base/entry etc.
149 */
150 static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
151 static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
152
udbg_rtascon_putc(char c)153 static void udbg_rtascon_putc(char c)
154 {
155 int tries;
156
157 if (!rtas.base)
158 return;
159
160 /* Add CRs before LFs */
161 if (c == '\n')
162 udbg_rtascon_putc('\r');
163
164 /* if there is more than one character to be displayed, wait a bit */
165 for (tries = 0; tries < 16; tries++) {
166 if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
167 break;
168 udelay(1000);
169 }
170 }
171
udbg_rtascon_getc_poll(void)172 static int udbg_rtascon_getc_poll(void)
173 {
174 int c;
175
176 if (!rtas.base)
177 return -1;
178
179 if (rtas_call(rtas_getchar_token, 0, 2, &c))
180 return -1;
181
182 return c;
183 }
184
udbg_rtascon_getc(void)185 static int udbg_rtascon_getc(void)
186 {
187 int c;
188
189 while ((c = udbg_rtascon_getc_poll()) == -1)
190 ;
191
192 return c;
193 }
194
195
udbg_init_rtas_console(void)196 void __init udbg_init_rtas_console(void)
197 {
198 udbg_putc = udbg_rtascon_putc;
199 udbg_getc = udbg_rtascon_getc;
200 udbg_getc_poll = udbg_rtascon_getc_poll;
201 }
202 #endif /* CONFIG_UDBG_RTAS_CONSOLE */
203
rtas_progress(char * s,unsigned short hex)204 void rtas_progress(char *s, unsigned short hex)
205 {
206 struct device_node *root;
207 int width;
208 const int *p;
209 char *os;
210 static int display_character, set_indicator;
211 static int display_width, display_lines, form_feed;
212 static const int *row_width;
213 static DEFINE_SPINLOCK(progress_lock);
214 static int current_line;
215 static int pending_newline = 0; /* did last write end with unprinted newline? */
216
217 if (!rtas.base)
218 return;
219
220 if (display_width == 0) {
221 display_width = 0x10;
222 if ((root = of_find_node_by_path("/rtas"))) {
223 if ((p = of_get_property(root,
224 "ibm,display-line-length", NULL)))
225 display_width = *p;
226 if ((p = of_get_property(root,
227 "ibm,form-feed", NULL)))
228 form_feed = *p;
229 if ((p = of_get_property(root,
230 "ibm,display-number-of-lines", NULL)))
231 display_lines = *p;
232 row_width = of_get_property(root,
233 "ibm,display-truncation-length", NULL);
234 of_node_put(root);
235 }
236 display_character = rtas_token("display-character");
237 set_indicator = rtas_token("set-indicator");
238 }
239
240 if (display_character == RTAS_UNKNOWN_SERVICE) {
241 /* use hex display if available */
242 if (set_indicator != RTAS_UNKNOWN_SERVICE)
243 rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
244 return;
245 }
246
247 spin_lock(&progress_lock);
248
249 /*
250 * Last write ended with newline, but we didn't print it since
251 * it would just clear the bottom line of output. Print it now
252 * instead.
253 *
254 * If no newline is pending and form feed is supported, clear the
255 * display with a form feed; otherwise, print a CR to start output
256 * at the beginning of the line.
257 */
258 if (pending_newline) {
259 rtas_call(display_character, 1, 1, NULL, '\r');
260 rtas_call(display_character, 1, 1, NULL, '\n');
261 pending_newline = 0;
262 } else {
263 current_line = 0;
264 if (form_feed)
265 rtas_call(display_character, 1, 1, NULL,
266 (char)form_feed);
267 else
268 rtas_call(display_character, 1, 1, NULL, '\r');
269 }
270
271 if (row_width)
272 width = row_width[current_line];
273 else
274 width = display_width;
275 os = s;
276 while (*os) {
277 if (*os == '\n' || *os == '\r') {
278 /* If newline is the last character, save it
279 * until next call to avoid bumping up the
280 * display output.
281 */
282 if (*os == '\n' && !os[1]) {
283 pending_newline = 1;
284 current_line++;
285 if (current_line > display_lines-1)
286 current_line = display_lines-1;
287 spin_unlock(&progress_lock);
288 return;
289 }
290
291 /* RTAS wants CR-LF, not just LF */
292
293 if (*os == '\n') {
294 rtas_call(display_character, 1, 1, NULL, '\r');
295 rtas_call(display_character, 1, 1, NULL, '\n');
296 } else {
297 /* CR might be used to re-draw a line, so we'll
298 * leave it alone and not add LF.
299 */
300 rtas_call(display_character, 1, 1, NULL, *os);
301 }
302
303 if (row_width)
304 width = row_width[current_line];
305 else
306 width = display_width;
307 } else {
308 width--;
309 rtas_call(display_character, 1, 1, NULL, *os);
310 }
311
312 os++;
313
314 /* if we overwrite the screen length */
315 if (width <= 0)
316 while ((*os != 0) && (*os != '\n') && (*os != '\r'))
317 os++;
318 }
319
320 spin_unlock(&progress_lock);
321 }
322 EXPORT_SYMBOL(rtas_progress); /* needed by rtas_flash module */
323
rtas_token(const char * service)324 int rtas_token(const char *service)
325 {
326 const int *tokp;
327 if (rtas.dev == NULL)
328 return RTAS_UNKNOWN_SERVICE;
329 tokp = of_get_property(rtas.dev, service, NULL);
330 return tokp ? *tokp : RTAS_UNKNOWN_SERVICE;
331 }
332 EXPORT_SYMBOL(rtas_token);
333
rtas_service_present(const char * service)334 int rtas_service_present(const char *service)
335 {
336 return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
337 }
338 EXPORT_SYMBOL(rtas_service_present);
339
340 #ifdef CONFIG_RTAS_ERROR_LOGGING
341 /*
342 * Return the firmware-specified size of the error log buffer
343 * for all rtas calls that require an error buffer argument.
344 * This includes 'check-exception' and 'rtas-last-error'.
345 */
rtas_get_error_log_max(void)346 int rtas_get_error_log_max(void)
347 {
348 static int rtas_error_log_max;
349 if (rtas_error_log_max)
350 return rtas_error_log_max;
351
352 rtas_error_log_max = rtas_token ("rtas-error-log-max");
353 if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
354 (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
355 printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
356 rtas_error_log_max);
357 rtas_error_log_max = RTAS_ERROR_LOG_MAX;
358 }
359 return rtas_error_log_max;
360 }
361 EXPORT_SYMBOL(rtas_get_error_log_max);
362
363
364 static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
365 static int rtas_last_error_token;
366
367 /** Return a copy of the detailed error text associated with the
368 * most recent failed call to rtas. Because the error text
369 * might go stale if there are any other intervening rtas calls,
370 * this routine must be called atomically with whatever produced
371 * the error (i.e. with rtas.lock still held from the previous call).
372 */
__fetch_rtas_last_error(char * altbuf)373 static char *__fetch_rtas_last_error(char *altbuf)
374 {
375 struct rtas_args err_args, save_args;
376 u32 bufsz;
377 char *buf = NULL;
378
379 if (rtas_last_error_token == -1)
380 return NULL;
381
382 bufsz = rtas_get_error_log_max();
383
384 err_args.token = rtas_last_error_token;
385 err_args.nargs = 2;
386 err_args.nret = 1;
387 err_args.args[0] = (rtas_arg_t)__pa(rtas_err_buf);
388 err_args.args[1] = bufsz;
389 err_args.args[2] = 0;
390
391 save_args = rtas.args;
392 rtas.args = err_args;
393
394 enter_rtas(__pa(&rtas.args));
395
396 err_args = rtas.args;
397 rtas.args = save_args;
398
399 /* Log the error in the unlikely case that there was one. */
400 if (unlikely(err_args.args[2] == 0)) {
401 if (altbuf) {
402 buf = altbuf;
403 } else {
404 buf = rtas_err_buf;
405 if (mem_init_done)
406 buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
407 }
408 if (buf)
409 memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
410 }
411
412 return buf;
413 }
414
415 #define get_errorlog_buffer() kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
416
417 #else /* CONFIG_RTAS_ERROR_LOGGING */
418 #define __fetch_rtas_last_error(x) NULL
419 #define get_errorlog_buffer() NULL
420 #endif
421
rtas_call(int token,int nargs,int nret,int * outputs,...)422 int rtas_call(int token, int nargs, int nret, int *outputs, ...)
423 {
424 va_list list;
425 int i;
426 unsigned long s;
427 struct rtas_args *rtas_args;
428 char *buff_copy = NULL;
429 int ret;
430
431 if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
432 return -1;
433
434 s = lock_rtas();
435 rtas_args = &rtas.args;
436
437 rtas_args->token = token;
438 rtas_args->nargs = nargs;
439 rtas_args->nret = nret;
440 rtas_args->rets = (rtas_arg_t *)&(rtas_args->args[nargs]);
441 va_start(list, outputs);
442 for (i = 0; i < nargs; ++i)
443 rtas_args->args[i] = va_arg(list, rtas_arg_t);
444 va_end(list);
445
446 for (i = 0; i < nret; ++i)
447 rtas_args->rets[i] = 0;
448
449 enter_rtas(__pa(rtas_args));
450
451 /* A -1 return code indicates that the last command couldn't
452 be completed due to a hardware error. */
453 if (rtas_args->rets[0] == -1)
454 buff_copy = __fetch_rtas_last_error(NULL);
455
456 if (nret > 1 && outputs != NULL)
457 for (i = 0; i < nret-1; ++i)
458 outputs[i] = rtas_args->rets[i+1];
459 ret = (nret > 0)? rtas_args->rets[0]: 0;
460
461 unlock_rtas(s);
462
463 if (buff_copy) {
464 log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
465 if (mem_init_done)
466 kfree(buff_copy);
467 }
468 return ret;
469 }
470 EXPORT_SYMBOL(rtas_call);
471
472 /* For RTAS_BUSY (-2), delay for 1 millisecond. For an extended busy status
473 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
474 */
rtas_busy_delay_time(int status)475 unsigned int rtas_busy_delay_time(int status)
476 {
477 int order;
478 unsigned int ms = 0;
479
480 if (status == RTAS_BUSY) {
481 ms = 1;
482 } else if (status >= 9900 && status <= 9905) {
483 order = status - 9900;
484 for (ms = 1; order > 0; order--)
485 ms *= 10;
486 }
487
488 return ms;
489 }
490 EXPORT_SYMBOL(rtas_busy_delay_time);
491
492 /* For an RTAS busy status code, perform the hinted delay. */
rtas_busy_delay(int status)493 unsigned int rtas_busy_delay(int status)
494 {
495 unsigned int ms;
496
497 might_sleep();
498 ms = rtas_busy_delay_time(status);
499 if (ms && need_resched())
500 msleep(ms);
501
502 return ms;
503 }
504 EXPORT_SYMBOL(rtas_busy_delay);
505
rtas_error_rc(int rtas_rc)506 static int rtas_error_rc(int rtas_rc)
507 {
508 int rc;
509
510 switch (rtas_rc) {
511 case -1: /* Hardware Error */
512 rc = -EIO;
513 break;
514 case -3: /* Bad indicator/domain/etc */
515 rc = -EINVAL;
516 break;
517 case -9000: /* Isolation error */
518 rc = -EFAULT;
519 break;
520 case -9001: /* Outstanding TCE/PTE */
521 rc = -EEXIST;
522 break;
523 case -9002: /* No usable slot */
524 rc = -ENODEV;
525 break;
526 default:
527 printk(KERN_ERR "%s: unexpected RTAS error %d\n",
528 __func__, rtas_rc);
529 rc = -ERANGE;
530 break;
531 }
532 return rc;
533 }
534
rtas_get_power_level(int powerdomain,int * level)535 int rtas_get_power_level(int powerdomain, int *level)
536 {
537 int token = rtas_token("get-power-level");
538 int rc;
539
540 if (token == RTAS_UNKNOWN_SERVICE)
541 return -ENOENT;
542
543 while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
544 udelay(1);
545
546 if (rc < 0)
547 return rtas_error_rc(rc);
548 return rc;
549 }
550 EXPORT_SYMBOL(rtas_get_power_level);
551
rtas_set_power_level(int powerdomain,int level,int * setlevel)552 int rtas_set_power_level(int powerdomain, int level, int *setlevel)
553 {
554 int token = rtas_token("set-power-level");
555 int rc;
556
557 if (token == RTAS_UNKNOWN_SERVICE)
558 return -ENOENT;
559
560 do {
561 rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
562 } while (rtas_busy_delay(rc));
563
564 if (rc < 0)
565 return rtas_error_rc(rc);
566 return rc;
567 }
568 EXPORT_SYMBOL(rtas_set_power_level);
569
rtas_get_sensor(int sensor,int index,int * state)570 int rtas_get_sensor(int sensor, int index, int *state)
571 {
572 int token = rtas_token("get-sensor-state");
573 int rc;
574
575 if (token == RTAS_UNKNOWN_SERVICE)
576 return -ENOENT;
577
578 do {
579 rc = rtas_call(token, 2, 2, state, sensor, index);
580 } while (rtas_busy_delay(rc));
581
582 if (rc < 0)
583 return rtas_error_rc(rc);
584 return rc;
585 }
586 EXPORT_SYMBOL(rtas_get_sensor);
587
rtas_indicator_present(int token,int * maxindex)588 bool rtas_indicator_present(int token, int *maxindex)
589 {
590 int proplen, count, i;
591 const struct indicator_elem {
592 u32 token;
593 u32 maxindex;
594 } *indicators;
595
596 indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
597 if (!indicators)
598 return false;
599
600 count = proplen / sizeof(struct indicator_elem);
601
602 for (i = 0; i < count; i++) {
603 if (indicators[i].token != token)
604 continue;
605 if (maxindex)
606 *maxindex = indicators[i].maxindex;
607 return true;
608 }
609
610 return false;
611 }
612 EXPORT_SYMBOL(rtas_indicator_present);
613
rtas_set_indicator(int indicator,int index,int new_value)614 int rtas_set_indicator(int indicator, int index, int new_value)
615 {
616 int token = rtas_token("set-indicator");
617 int rc;
618
619 if (token == RTAS_UNKNOWN_SERVICE)
620 return -ENOENT;
621
622 do {
623 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
624 } while (rtas_busy_delay(rc));
625
626 if (rc < 0)
627 return rtas_error_rc(rc);
628 return rc;
629 }
630 EXPORT_SYMBOL(rtas_set_indicator);
631
632 /*
633 * Ignoring RTAS extended delay
634 */
rtas_set_indicator_fast(int indicator,int index,int new_value)635 int rtas_set_indicator_fast(int indicator, int index, int new_value)
636 {
637 int rc;
638 int token = rtas_token("set-indicator");
639
640 if (token == RTAS_UNKNOWN_SERVICE)
641 return -ENOENT;
642
643 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
644
645 WARN_ON(rc == -2 || (rc >= 9900 && rc <= 9905));
646
647 if (rc < 0)
648 return rtas_error_rc(rc);
649
650 return rc;
651 }
652
rtas_restart(char * cmd)653 void rtas_restart(char *cmd)
654 {
655 if (rtas_flash_term_hook)
656 rtas_flash_term_hook(SYS_RESTART);
657 printk("RTAS system-reboot returned %d\n",
658 rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
659 for (;;);
660 }
661
rtas_power_off(void)662 void rtas_power_off(void)
663 {
664 if (rtas_flash_term_hook)
665 rtas_flash_term_hook(SYS_POWER_OFF);
666 /* allow power on only with power button press */
667 printk("RTAS power-off returned %d\n",
668 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
669 for (;;);
670 }
671
rtas_halt(void)672 void rtas_halt(void)
673 {
674 if (rtas_flash_term_hook)
675 rtas_flash_term_hook(SYS_HALT);
676 /* allow power on only with power button press */
677 printk("RTAS power-off returned %d\n",
678 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
679 for (;;);
680 }
681
682 /* Must be in the RMO region, so we place it here */
683 static char rtas_os_term_buf[2048];
684
rtas_os_term(char * str)685 void rtas_os_term(char *str)
686 {
687 int status;
688
689 /*
690 * Firmware with the ibm,extended-os-term property is guaranteed
691 * to always return from an ibm,os-term call. Earlier versions without
692 * this property may terminate the partition which we want to avoid
693 * since it interferes with panic_timeout.
694 */
695 if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
696 RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
697 return;
698
699 snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
700
701 do {
702 status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
703 __pa(rtas_os_term_buf));
704 } while (rtas_busy_delay(status));
705
706 if (status != 0)
707 printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
708 }
709
710 static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
711 #ifdef CONFIG_PPC_PSERIES
__rtas_suspend_last_cpu(struct rtas_suspend_me_data * data,int wake_when_done)712 static int __rtas_suspend_last_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
713 {
714 u16 slb_size = mmu_slb_size;
715 int rc = H_MULTI_THREADS_ACTIVE;
716 int cpu;
717
718 slb_set_size(SLB_MIN_SIZE);
719 printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n", smp_processor_id());
720
721 while (rc == H_MULTI_THREADS_ACTIVE && !atomic_read(&data->done) &&
722 !atomic_read(&data->error))
723 rc = rtas_call(data->token, 0, 1, NULL);
724
725 if (rc || atomic_read(&data->error)) {
726 printk(KERN_DEBUG "ibm,suspend-me returned %d\n", rc);
727 slb_set_size(slb_size);
728 }
729
730 if (atomic_read(&data->error))
731 rc = atomic_read(&data->error);
732
733 atomic_set(&data->error, rc);
734 pSeries_coalesce_init();
735
736 if (wake_when_done) {
737 atomic_set(&data->done, 1);
738
739 for_each_online_cpu(cpu)
740 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
741 }
742
743 if (atomic_dec_return(&data->working) == 0)
744 complete(data->complete);
745
746 return rc;
747 }
748
rtas_suspend_last_cpu(struct rtas_suspend_me_data * data)749 int rtas_suspend_last_cpu(struct rtas_suspend_me_data *data)
750 {
751 atomic_inc(&data->working);
752 return __rtas_suspend_last_cpu(data, 0);
753 }
754
__rtas_suspend_cpu(struct rtas_suspend_me_data * data,int wake_when_done)755 static int __rtas_suspend_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
756 {
757 long rc = H_SUCCESS;
758 unsigned long msr_save;
759 int cpu;
760
761 atomic_inc(&data->working);
762
763 /* really need to ensure MSR.EE is off for H_JOIN */
764 msr_save = mfmsr();
765 mtmsr(msr_save & ~(MSR_EE));
766
767 while (rc == H_SUCCESS && !atomic_read(&data->done) && !atomic_read(&data->error))
768 rc = plpar_hcall_norets(H_JOIN);
769
770 mtmsr(msr_save);
771
772 if (rc == H_SUCCESS) {
773 /* This cpu was prodded and the suspend is complete. */
774 goto out;
775 } else if (rc == H_CONTINUE) {
776 /* All other cpus are in H_JOIN, this cpu does
777 * the suspend.
778 */
779 return __rtas_suspend_last_cpu(data, wake_when_done);
780 } else {
781 printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
782 smp_processor_id(), rc);
783 atomic_set(&data->error, rc);
784 }
785
786 if (wake_when_done) {
787 atomic_set(&data->done, 1);
788
789 /* This cpu did the suspend or got an error; in either case,
790 * we need to prod all other other cpus out of join state.
791 * Extra prods are harmless.
792 */
793 for_each_online_cpu(cpu)
794 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
795 }
796 out:
797 if (atomic_dec_return(&data->working) == 0)
798 complete(data->complete);
799 return rc;
800 }
801
rtas_suspend_cpu(struct rtas_suspend_me_data * data)802 int rtas_suspend_cpu(struct rtas_suspend_me_data *data)
803 {
804 return __rtas_suspend_cpu(data, 0);
805 }
806
rtas_percpu_suspend_me(void * info)807 static void rtas_percpu_suspend_me(void *info)
808 {
809 __rtas_suspend_cpu((struct rtas_suspend_me_data *)info, 1);
810 }
811
812 enum rtas_cpu_state {
813 DOWN,
814 UP,
815 };
816
817 #ifndef CONFIG_SMP
rtas_cpu_state_change_mask(enum rtas_cpu_state state,cpumask_var_t cpus)818 static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
819 cpumask_var_t cpus)
820 {
821 if (!cpumask_empty(cpus)) {
822 cpumask_clear(cpus);
823 return -EINVAL;
824 } else
825 return 0;
826 }
827 #else
828 /* On return cpumask will be altered to indicate CPUs changed.
829 * CPUs with states changed will be set in the mask,
830 * CPUs with status unchanged will be unset in the mask. */
rtas_cpu_state_change_mask(enum rtas_cpu_state state,cpumask_var_t cpus)831 static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
832 cpumask_var_t cpus)
833 {
834 int cpu;
835 int cpuret = 0;
836 int ret = 0;
837
838 if (cpumask_empty(cpus))
839 return 0;
840
841 for_each_cpu(cpu, cpus) {
842 switch (state) {
843 case DOWN:
844 cpuret = cpu_down(cpu);
845 break;
846 case UP:
847 cpuret = cpu_up(cpu);
848 break;
849 }
850 if (cpuret) {
851 pr_debug("%s: cpu_%s for cpu#%d returned %d.\n",
852 __func__,
853 ((state == UP) ? "up" : "down"),
854 cpu, cpuret);
855 if (!ret)
856 ret = cpuret;
857 if (state == UP) {
858 /* clear bits for unchanged cpus, return */
859 cpumask_shift_right(cpus, cpus, cpu);
860 cpumask_shift_left(cpus, cpus, cpu);
861 break;
862 } else {
863 /* clear bit for unchanged cpu, continue */
864 cpumask_clear_cpu(cpu, cpus);
865 }
866 }
867 }
868
869 return ret;
870 }
871 #endif
872
rtas_online_cpus_mask(cpumask_var_t cpus)873 int rtas_online_cpus_mask(cpumask_var_t cpus)
874 {
875 int ret;
876
877 ret = rtas_cpu_state_change_mask(UP, cpus);
878
879 if (ret) {
880 cpumask_var_t tmp_mask;
881
882 if (!alloc_cpumask_var(&tmp_mask, GFP_TEMPORARY))
883 return ret;
884
885 /* Use tmp_mask to preserve cpus mask from first failure */
886 cpumask_copy(tmp_mask, cpus);
887 rtas_offline_cpus_mask(tmp_mask);
888 free_cpumask_var(tmp_mask);
889 }
890
891 return ret;
892 }
893 EXPORT_SYMBOL(rtas_online_cpus_mask);
894
rtas_offline_cpus_mask(cpumask_var_t cpus)895 int rtas_offline_cpus_mask(cpumask_var_t cpus)
896 {
897 return rtas_cpu_state_change_mask(DOWN, cpus);
898 }
899 EXPORT_SYMBOL(rtas_offline_cpus_mask);
900
rtas_ibm_suspend_me(struct rtas_args * args)901 int rtas_ibm_suspend_me(struct rtas_args *args)
902 {
903 long state;
904 long rc;
905 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
906 struct rtas_suspend_me_data data;
907 DECLARE_COMPLETION_ONSTACK(done);
908 cpumask_var_t offline_mask;
909 int cpuret;
910
911 if (!rtas_service_present("ibm,suspend-me"))
912 return -ENOSYS;
913
914 /* Make sure the state is valid */
915 rc = plpar_hcall(H_VASI_STATE, retbuf,
916 ((u64)args->args[0] << 32) | args->args[1]);
917
918 state = retbuf[0];
919
920 if (rc) {
921 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
922 return rc;
923 } else if (state == H_VASI_ENABLED) {
924 args->args[args->nargs] = RTAS_NOT_SUSPENDABLE;
925 return 0;
926 } else if (state != H_VASI_SUSPENDING) {
927 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
928 state);
929 args->args[args->nargs] = -1;
930 return 0;
931 }
932
933 if (!alloc_cpumask_var(&offline_mask, GFP_TEMPORARY))
934 return -ENOMEM;
935
936 atomic_set(&data.working, 0);
937 atomic_set(&data.done, 0);
938 atomic_set(&data.error, 0);
939 data.token = rtas_token("ibm,suspend-me");
940 data.complete = &done;
941
942 /* All present CPUs must be online */
943 cpumask_andnot(offline_mask, cpu_present_mask, cpu_online_mask);
944 cpuret = rtas_online_cpus_mask(offline_mask);
945 if (cpuret) {
946 pr_err("%s: Could not bring present CPUs online.\n", __func__);
947 atomic_set(&data.error, cpuret);
948 goto out;
949 }
950
951 stop_topology_update();
952
953 /* Call function on all CPUs. One of us will make the
954 * rtas call
955 */
956 if (on_each_cpu(rtas_percpu_suspend_me, &data, 0))
957 atomic_set(&data.error, -EINVAL);
958
959 wait_for_completion(&done);
960
961 if (atomic_read(&data.error) != 0)
962 printk(KERN_ERR "Error doing global join\n");
963
964 start_topology_update();
965
966 /* Take down CPUs not online prior to suspend */
967 cpuret = rtas_offline_cpus_mask(offline_mask);
968 if (cpuret)
969 pr_warn("%s: Could not restore CPUs to offline state.\n",
970 __func__);
971
972 out:
973 free_cpumask_var(offline_mask);
974 return atomic_read(&data.error);
975 }
976 #else /* CONFIG_PPC_PSERIES */
rtas_ibm_suspend_me(struct rtas_args * args)977 int rtas_ibm_suspend_me(struct rtas_args *args)
978 {
979 return -ENOSYS;
980 }
981 #endif
982
983 /**
984 * Find a specific pseries error log in an RTAS extended event log.
985 * @log: RTAS error/event log
986 * @section_id: two character section identifier
987 *
988 * Returns a pointer to the specified errorlog or NULL if not found.
989 */
get_pseries_errorlog(struct rtas_error_log * log,uint16_t section_id)990 struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
991 uint16_t section_id)
992 {
993 struct rtas_ext_event_log_v6 *ext_log =
994 (struct rtas_ext_event_log_v6 *)log->buffer;
995 struct pseries_errorlog *sect;
996 unsigned char *p, *log_end;
997
998 /* Check that we understand the format */
999 if (log->extended_log_length < sizeof(struct rtas_ext_event_log_v6) ||
1000 ext_log->log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
1001 ext_log->company_id != RTAS_V6EXT_COMPANY_ID_IBM)
1002 return NULL;
1003
1004 log_end = log->buffer + log->extended_log_length;
1005 p = ext_log->vendor_log;
1006
1007 while (p < log_end) {
1008 sect = (struct pseries_errorlog *)p;
1009 if (sect->id == section_id)
1010 return sect;
1011 p += sect->length;
1012 }
1013
1014 return NULL;
1015 }
1016
ppc_rtas(struct rtas_args __user * uargs)1017 asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
1018 {
1019 struct rtas_args args;
1020 unsigned long flags;
1021 char *buff_copy, *errbuf = NULL;
1022 int nargs;
1023 int rc;
1024
1025 if (!capable(CAP_SYS_ADMIN))
1026 return -EPERM;
1027
1028 if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
1029 return -EFAULT;
1030
1031 nargs = args.nargs;
1032 if (nargs > ARRAY_SIZE(args.args)
1033 || args.nret > ARRAY_SIZE(args.args)
1034 || nargs + args.nret > ARRAY_SIZE(args.args))
1035 return -EINVAL;
1036
1037 /* Copy in args. */
1038 if (copy_from_user(args.args, uargs->args,
1039 nargs * sizeof(rtas_arg_t)) != 0)
1040 return -EFAULT;
1041
1042 if (args.token == RTAS_UNKNOWN_SERVICE)
1043 return -EINVAL;
1044
1045 args.rets = &args.args[nargs];
1046 memset(args.rets, 0, args.nret * sizeof(rtas_arg_t));
1047
1048 /* Need to handle ibm,suspend_me call specially */
1049 if (args.token == ibm_suspend_me_token) {
1050 rc = rtas_ibm_suspend_me(&args);
1051 if (rc)
1052 return rc;
1053 goto copy_return;
1054 }
1055
1056 buff_copy = get_errorlog_buffer();
1057
1058 flags = lock_rtas();
1059
1060 rtas.args = args;
1061 enter_rtas(__pa(&rtas.args));
1062 args = rtas.args;
1063
1064 /* A -1 return code indicates that the last command couldn't
1065 be completed due to a hardware error. */
1066 if (args.rets[0] == -1)
1067 errbuf = __fetch_rtas_last_error(buff_copy);
1068
1069 unlock_rtas(flags);
1070
1071 if (buff_copy) {
1072 if (errbuf)
1073 log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
1074 kfree(buff_copy);
1075 }
1076
1077 copy_return:
1078 /* Copy out args. */
1079 if (copy_to_user(uargs->args + nargs,
1080 args.args + nargs,
1081 args.nret * sizeof(rtas_arg_t)) != 0)
1082 return -EFAULT;
1083
1084 return 0;
1085 }
1086
1087 /*
1088 * Call early during boot, before mem init or bootmem, to retrieve the RTAS
1089 * informations from the device-tree and allocate the RMO buffer for userland
1090 * accesses.
1091 */
rtas_initialize(void)1092 void __init rtas_initialize(void)
1093 {
1094 unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
1095
1096 /* Get RTAS dev node and fill up our "rtas" structure with infos
1097 * about it.
1098 */
1099 rtas.dev = of_find_node_by_name(NULL, "rtas");
1100 if (rtas.dev) {
1101 const u32 *basep, *entryp, *sizep;
1102
1103 basep = of_get_property(rtas.dev, "linux,rtas-base", NULL);
1104 sizep = of_get_property(rtas.dev, "rtas-size", NULL);
1105 if (basep != NULL && sizep != NULL) {
1106 rtas.base = *basep;
1107 rtas.size = *sizep;
1108 entryp = of_get_property(rtas.dev,
1109 "linux,rtas-entry", NULL);
1110 if (entryp == NULL) /* Ugh */
1111 rtas.entry = rtas.base;
1112 else
1113 rtas.entry = *entryp;
1114 } else
1115 rtas.dev = NULL;
1116 }
1117 if (!rtas.dev)
1118 return;
1119
1120 /* If RTAS was found, allocate the RMO buffer for it and look for
1121 * the stop-self token if any
1122 */
1123 #ifdef CONFIG_PPC64
1124 if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
1125 rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
1126 ibm_suspend_me_token = rtas_token("ibm,suspend-me");
1127 }
1128 #endif
1129 rtas_rmo_buf = memblock_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
1130
1131 #ifdef CONFIG_RTAS_ERROR_LOGGING
1132 rtas_last_error_token = rtas_token("rtas-last-error");
1133 #endif
1134 }
1135
early_init_dt_scan_rtas(unsigned long node,const char * uname,int depth,void * data)1136 int __init early_init_dt_scan_rtas(unsigned long node,
1137 const char *uname, int depth, void *data)
1138 {
1139 u32 *basep, *entryp, *sizep;
1140
1141 if (depth != 1 || strcmp(uname, "rtas") != 0)
1142 return 0;
1143
1144 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
1145 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
1146 sizep = of_get_flat_dt_prop(node, "rtas-size", NULL);
1147
1148 if (basep && entryp && sizep) {
1149 rtas.base = *basep;
1150 rtas.entry = *entryp;
1151 rtas.size = *sizep;
1152 }
1153
1154 #ifdef CONFIG_UDBG_RTAS_CONSOLE
1155 basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1156 if (basep)
1157 rtas_putchar_token = *basep;
1158
1159 basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1160 if (basep)
1161 rtas_getchar_token = *basep;
1162
1163 if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1164 rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1165 udbg_init_rtas_console();
1166
1167 #endif
1168
1169 /* break now */
1170 return 1;
1171 }
1172
1173 static arch_spinlock_t timebase_lock;
1174 static u64 timebase = 0;
1175
rtas_give_timebase(void)1176 void __cpuinit rtas_give_timebase(void)
1177 {
1178 unsigned long flags;
1179
1180 local_irq_save(flags);
1181 hard_irq_disable();
1182 arch_spin_lock(&timebase_lock);
1183 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1184 timebase = get_tb();
1185 arch_spin_unlock(&timebase_lock);
1186
1187 while (timebase)
1188 barrier();
1189 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1190 local_irq_restore(flags);
1191 }
1192
rtas_take_timebase(void)1193 void __cpuinit rtas_take_timebase(void)
1194 {
1195 while (!timebase)
1196 barrier();
1197 arch_spin_lock(&timebase_lock);
1198 set_tb(timebase >> 32, timebase & 0xffffffff);
1199 timebase = 0;
1200 arch_spin_unlock(&timebase_lock);
1201 }
1202