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
47 struct rtas_t rtas = {
48 .lock = __ARCH_SPIN_LOCK_UNLOCKED
49 };
50 EXPORT_SYMBOL(rtas);
51
52 DEFINE_SPINLOCK(rtas_data_buf_lock);
53 EXPORT_SYMBOL(rtas_data_buf_lock);
54
55 char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
56 EXPORT_SYMBOL(rtas_data_buf);
57
58 unsigned long rtas_rmo_buf;
59
60 /*
61 * If non-NULL, this gets called when the kernel terminates.
62 * This is done like this so rtas_flash can be a module.
63 */
64 void (*rtas_flash_term_hook)(int);
65 EXPORT_SYMBOL(rtas_flash_term_hook);
66
67 /* RTAS use home made raw locking instead of spin_lock_irqsave
68 * because those can be called from within really nasty contexts
69 * such as having the timebase stopped which would lockup with
70 * normal locks and spinlock debugging enabled
71 */
lock_rtas(void)72 static unsigned long lock_rtas(void)
73 {
74 unsigned long flags;
75
76 local_irq_save(flags);
77 preempt_disable();
78 arch_spin_lock_flags(&rtas.lock, flags);
79 return flags;
80 }
81
unlock_rtas(unsigned long flags)82 static void unlock_rtas(unsigned long flags)
83 {
84 arch_spin_unlock(&rtas.lock);
85 local_irq_restore(flags);
86 preempt_enable();
87 }
88
89 /*
90 * call_rtas_display_status and call_rtas_display_status_delay
91 * are designed only for very early low-level debugging, which
92 * is why the token is hard-coded to 10.
93 */
call_rtas_display_status(char c)94 static void call_rtas_display_status(char c)
95 {
96 struct rtas_args *args = &rtas.args;
97 unsigned long s;
98
99 if (!rtas.base)
100 return;
101 s = lock_rtas();
102
103 args->token = 10;
104 args->nargs = 1;
105 args->nret = 1;
106 args->rets = (rtas_arg_t *)&(args->args[1]);
107 args->args[0] = (unsigned char)c;
108
109 enter_rtas(__pa(args));
110
111 unlock_rtas(s);
112 }
113
call_rtas_display_status_delay(char c)114 static void call_rtas_display_status_delay(char c)
115 {
116 static int pending_newline = 0; /* did last write end with unprinted newline? */
117 static int width = 16;
118
119 if (c == '\n') {
120 while (width-- > 0)
121 call_rtas_display_status(' ');
122 width = 16;
123 mdelay(500);
124 pending_newline = 1;
125 } else {
126 if (pending_newline) {
127 call_rtas_display_status('\r');
128 call_rtas_display_status('\n');
129 }
130 pending_newline = 0;
131 if (width--) {
132 call_rtas_display_status(c);
133 udelay(10000);
134 }
135 }
136 }
137
udbg_init_rtas_panel(void)138 void __init udbg_init_rtas_panel(void)
139 {
140 udbg_putc = call_rtas_display_status_delay;
141 }
142
143 #ifdef CONFIG_UDBG_RTAS_CONSOLE
144
145 /* If you think you're dying before early_init_dt_scan_rtas() does its
146 * work, you can hard code the token values for your firmware here and
147 * hardcode rtas.base/entry etc.
148 */
149 static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
150 static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
151
udbg_rtascon_putc(char c)152 static void udbg_rtascon_putc(char c)
153 {
154 int tries;
155
156 if (!rtas.base)
157 return;
158
159 /* Add CRs before LFs */
160 if (c == '\n')
161 udbg_rtascon_putc('\r');
162
163 /* if there is more than one character to be displayed, wait a bit */
164 for (tries = 0; tries < 16; tries++) {
165 if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
166 break;
167 udelay(1000);
168 }
169 }
170
udbg_rtascon_getc_poll(void)171 static int udbg_rtascon_getc_poll(void)
172 {
173 int c;
174
175 if (!rtas.base)
176 return -1;
177
178 if (rtas_call(rtas_getchar_token, 0, 2, &c))
179 return -1;
180
181 return c;
182 }
183
udbg_rtascon_getc(void)184 static int udbg_rtascon_getc(void)
185 {
186 int c;
187
188 while ((c = udbg_rtascon_getc_poll()) == -1)
189 ;
190
191 return c;
192 }
193
194
udbg_init_rtas_console(void)195 void __init udbg_init_rtas_console(void)
196 {
197 udbg_putc = udbg_rtascon_putc;
198 udbg_getc = udbg_rtascon_getc;
199 udbg_getc_poll = udbg_rtascon_getc_poll;
200 }
201 #endif /* CONFIG_UDBG_RTAS_CONSOLE */
202
rtas_progress(char * s,unsigned short hex)203 void rtas_progress(char *s, unsigned short hex)
204 {
205 struct device_node *root;
206 int width;
207 const int *p;
208 char *os;
209 static int display_character, set_indicator;
210 static int display_width, display_lines, form_feed;
211 static const int *row_width;
212 static DEFINE_SPINLOCK(progress_lock);
213 static int current_line;
214 static int pending_newline = 0; /* did last write end with unprinted newline? */
215
216 if (!rtas.base)
217 return;
218
219 if (display_width == 0) {
220 display_width = 0x10;
221 if ((root = of_find_node_by_path("/rtas"))) {
222 if ((p = of_get_property(root,
223 "ibm,display-line-length", NULL)))
224 display_width = *p;
225 if ((p = of_get_property(root,
226 "ibm,form-feed", NULL)))
227 form_feed = *p;
228 if ((p = of_get_property(root,
229 "ibm,display-number-of-lines", NULL)))
230 display_lines = *p;
231 row_width = of_get_property(root,
232 "ibm,display-truncation-length", NULL);
233 of_node_put(root);
234 }
235 display_character = rtas_token("display-character");
236 set_indicator = rtas_token("set-indicator");
237 }
238
239 if (display_character == RTAS_UNKNOWN_SERVICE) {
240 /* use hex display if available */
241 if (set_indicator != RTAS_UNKNOWN_SERVICE)
242 rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
243 return;
244 }
245
246 spin_lock(&progress_lock);
247
248 /*
249 * Last write ended with newline, but we didn't print it since
250 * it would just clear the bottom line of output. Print it now
251 * instead.
252 *
253 * If no newline is pending and form feed is supported, clear the
254 * display with a form feed; otherwise, print a CR to start output
255 * at the beginning of the line.
256 */
257 if (pending_newline) {
258 rtas_call(display_character, 1, 1, NULL, '\r');
259 rtas_call(display_character, 1, 1, NULL, '\n');
260 pending_newline = 0;
261 } else {
262 current_line = 0;
263 if (form_feed)
264 rtas_call(display_character, 1, 1, NULL,
265 (char)form_feed);
266 else
267 rtas_call(display_character, 1, 1, NULL, '\r');
268 }
269
270 if (row_width)
271 width = row_width[current_line];
272 else
273 width = display_width;
274 os = s;
275 while (*os) {
276 if (*os == '\n' || *os == '\r') {
277 /* If newline is the last character, save it
278 * until next call to avoid bumping up the
279 * display output.
280 */
281 if (*os == '\n' && !os[1]) {
282 pending_newline = 1;
283 current_line++;
284 if (current_line > display_lines-1)
285 current_line = display_lines-1;
286 spin_unlock(&progress_lock);
287 return;
288 }
289
290 /* RTAS wants CR-LF, not just LF */
291
292 if (*os == '\n') {
293 rtas_call(display_character, 1, 1, NULL, '\r');
294 rtas_call(display_character, 1, 1, NULL, '\n');
295 } else {
296 /* CR might be used to re-draw a line, so we'll
297 * leave it alone and not add LF.
298 */
299 rtas_call(display_character, 1, 1, NULL, *os);
300 }
301
302 if (row_width)
303 width = row_width[current_line];
304 else
305 width = display_width;
306 } else {
307 width--;
308 rtas_call(display_character, 1, 1, NULL, *os);
309 }
310
311 os++;
312
313 /* if we overwrite the screen length */
314 if (width <= 0)
315 while ((*os != 0) && (*os != '\n') && (*os != '\r'))
316 os++;
317 }
318
319 spin_unlock(&progress_lock);
320 }
321 EXPORT_SYMBOL(rtas_progress); /* needed by rtas_flash module */
322
rtas_token(const char * service)323 int rtas_token(const char *service)
324 {
325 const int *tokp;
326 if (rtas.dev == NULL)
327 return RTAS_UNKNOWN_SERVICE;
328 tokp = of_get_property(rtas.dev, service, NULL);
329 return tokp ? *tokp : RTAS_UNKNOWN_SERVICE;
330 }
331 EXPORT_SYMBOL(rtas_token);
332
rtas_service_present(const char * service)333 int rtas_service_present(const char *service)
334 {
335 return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
336 }
337 EXPORT_SYMBOL(rtas_service_present);
338
339 #ifdef CONFIG_RTAS_ERROR_LOGGING
340 /*
341 * Return the firmware-specified size of the error log buffer
342 * for all rtas calls that require an error buffer argument.
343 * This includes 'check-exception' and 'rtas-last-error'.
344 */
rtas_get_error_log_max(void)345 int rtas_get_error_log_max(void)
346 {
347 static int rtas_error_log_max;
348 if (rtas_error_log_max)
349 return rtas_error_log_max;
350
351 rtas_error_log_max = rtas_token ("rtas-error-log-max");
352 if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
353 (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
354 printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
355 rtas_error_log_max);
356 rtas_error_log_max = RTAS_ERROR_LOG_MAX;
357 }
358 return rtas_error_log_max;
359 }
360 EXPORT_SYMBOL(rtas_get_error_log_max);
361
362
363 static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
364 static int rtas_last_error_token;
365
366 /** Return a copy of the detailed error text associated with the
367 * most recent failed call to rtas. Because the error text
368 * might go stale if there are any other intervening rtas calls,
369 * this routine must be called atomically with whatever produced
370 * the error (i.e. with rtas.lock still held from the previous call).
371 */
__fetch_rtas_last_error(char * altbuf)372 static char *__fetch_rtas_last_error(char *altbuf)
373 {
374 struct rtas_args err_args, save_args;
375 u32 bufsz;
376 char *buf = NULL;
377
378 if (rtas_last_error_token == -1)
379 return NULL;
380
381 bufsz = rtas_get_error_log_max();
382
383 err_args.token = rtas_last_error_token;
384 err_args.nargs = 2;
385 err_args.nret = 1;
386 err_args.args[0] = (rtas_arg_t)__pa(rtas_err_buf);
387 err_args.args[1] = bufsz;
388 err_args.args[2] = 0;
389
390 save_args = rtas.args;
391 rtas.args = err_args;
392
393 enter_rtas(__pa(&rtas.args));
394
395 err_args = rtas.args;
396 rtas.args = save_args;
397
398 /* Log the error in the unlikely case that there was one. */
399 if (unlikely(err_args.args[2] == 0)) {
400 if (altbuf) {
401 buf = altbuf;
402 } else {
403 buf = rtas_err_buf;
404 if (mem_init_done)
405 buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
406 }
407 if (buf)
408 memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
409 }
410
411 return buf;
412 }
413
414 #define get_errorlog_buffer() kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
415
416 #else /* CONFIG_RTAS_ERROR_LOGGING */
417 #define __fetch_rtas_last_error(x) NULL
418 #define get_errorlog_buffer() NULL
419 #endif
420
rtas_call(int token,int nargs,int nret,int * outputs,...)421 int rtas_call(int token, int nargs, int nret, int *outputs, ...)
422 {
423 va_list list;
424 int i;
425 unsigned long s;
426 struct rtas_args *rtas_args;
427 char *buff_copy = NULL;
428 int ret;
429
430 if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
431 return -1;
432
433 s = lock_rtas();
434 rtas_args = &rtas.args;
435
436 rtas_args->token = token;
437 rtas_args->nargs = nargs;
438 rtas_args->nret = nret;
439 rtas_args->rets = (rtas_arg_t *)&(rtas_args->args[nargs]);
440 va_start(list, outputs);
441 for (i = 0; i < nargs; ++i)
442 rtas_args->args[i] = va_arg(list, rtas_arg_t);
443 va_end(list);
444
445 for (i = 0; i < nret; ++i)
446 rtas_args->rets[i] = 0;
447
448 enter_rtas(__pa(rtas_args));
449
450 /* A -1 return code indicates that the last command couldn't
451 be completed due to a hardware error. */
452 if (rtas_args->rets[0] == -1)
453 buff_copy = __fetch_rtas_last_error(NULL);
454
455 if (nret > 1 && outputs != NULL)
456 for (i = 0; i < nret-1; ++i)
457 outputs[i] = rtas_args->rets[i+1];
458 ret = (nret > 0)? rtas_args->rets[0]: 0;
459
460 unlock_rtas(s);
461
462 if (buff_copy) {
463 log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
464 if (mem_init_done)
465 kfree(buff_copy);
466 }
467 return ret;
468 }
469 EXPORT_SYMBOL(rtas_call);
470
471 /* For RTAS_BUSY (-2), delay for 1 millisecond. For an extended busy status
472 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
473 */
rtas_busy_delay_time(int status)474 unsigned int rtas_busy_delay_time(int status)
475 {
476 int order;
477 unsigned int ms = 0;
478
479 if (status == RTAS_BUSY) {
480 ms = 1;
481 } else if (status >= 9900 && status <= 9905) {
482 order = status - 9900;
483 for (ms = 1; order > 0; order--)
484 ms *= 10;
485 }
486
487 return ms;
488 }
489 EXPORT_SYMBOL(rtas_busy_delay_time);
490
491 /* For an RTAS busy status code, perform the hinted delay. */
rtas_busy_delay(int status)492 unsigned int rtas_busy_delay(int status)
493 {
494 unsigned int ms;
495
496 might_sleep();
497 ms = rtas_busy_delay_time(status);
498 if (ms && need_resched())
499 msleep(ms);
500
501 return ms;
502 }
503 EXPORT_SYMBOL(rtas_busy_delay);
504
rtas_error_rc(int rtas_rc)505 static int rtas_error_rc(int rtas_rc)
506 {
507 int rc;
508
509 switch (rtas_rc) {
510 case -1: /* Hardware Error */
511 rc = -EIO;
512 break;
513 case -3: /* Bad indicator/domain/etc */
514 rc = -EINVAL;
515 break;
516 case -9000: /* Isolation error */
517 rc = -EFAULT;
518 break;
519 case -9001: /* Outstanding TCE/PTE */
520 rc = -EEXIST;
521 break;
522 case -9002: /* No usable slot */
523 rc = -ENODEV;
524 break;
525 default:
526 printk(KERN_ERR "%s: unexpected RTAS error %d\n",
527 __func__, rtas_rc);
528 rc = -ERANGE;
529 break;
530 }
531 return rc;
532 }
533
rtas_get_power_level(int powerdomain,int * level)534 int rtas_get_power_level(int powerdomain, int *level)
535 {
536 int token = rtas_token("get-power-level");
537 int rc;
538
539 if (token == RTAS_UNKNOWN_SERVICE)
540 return -ENOENT;
541
542 while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
543 udelay(1);
544
545 if (rc < 0)
546 return rtas_error_rc(rc);
547 return rc;
548 }
549 EXPORT_SYMBOL(rtas_get_power_level);
550
rtas_set_power_level(int powerdomain,int level,int * setlevel)551 int rtas_set_power_level(int powerdomain, int level, int *setlevel)
552 {
553 int token = rtas_token("set-power-level");
554 int rc;
555
556 if (token == RTAS_UNKNOWN_SERVICE)
557 return -ENOENT;
558
559 do {
560 rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
561 } while (rtas_busy_delay(rc));
562
563 if (rc < 0)
564 return rtas_error_rc(rc);
565 return rc;
566 }
567 EXPORT_SYMBOL(rtas_set_power_level);
568
rtas_get_sensor(int sensor,int index,int * state)569 int rtas_get_sensor(int sensor, int index, int *state)
570 {
571 int token = rtas_token("get-sensor-state");
572 int rc;
573
574 if (token == RTAS_UNKNOWN_SERVICE)
575 return -ENOENT;
576
577 do {
578 rc = rtas_call(token, 2, 2, state, sensor, index);
579 } while (rtas_busy_delay(rc));
580
581 if (rc < 0)
582 return rtas_error_rc(rc);
583 return rc;
584 }
585 EXPORT_SYMBOL(rtas_get_sensor);
586
rtas_indicator_present(int token,int * maxindex)587 bool rtas_indicator_present(int token, int *maxindex)
588 {
589 int proplen, count, i;
590 const struct indicator_elem {
591 u32 token;
592 u32 maxindex;
593 } *indicators;
594
595 indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
596 if (!indicators)
597 return false;
598
599 count = proplen / sizeof(struct indicator_elem);
600
601 for (i = 0; i < count; i++) {
602 if (indicators[i].token != token)
603 continue;
604 if (maxindex)
605 *maxindex = indicators[i].maxindex;
606 return true;
607 }
608
609 return false;
610 }
611 EXPORT_SYMBOL(rtas_indicator_present);
612
rtas_set_indicator(int indicator,int index,int new_value)613 int rtas_set_indicator(int indicator, int index, int new_value)
614 {
615 int token = rtas_token("set-indicator");
616 int rc;
617
618 if (token == RTAS_UNKNOWN_SERVICE)
619 return -ENOENT;
620
621 do {
622 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
623 } while (rtas_busy_delay(rc));
624
625 if (rc < 0)
626 return rtas_error_rc(rc);
627 return rc;
628 }
629 EXPORT_SYMBOL(rtas_set_indicator);
630
631 /*
632 * Ignoring RTAS extended delay
633 */
rtas_set_indicator_fast(int indicator,int index,int new_value)634 int rtas_set_indicator_fast(int indicator, int index, int new_value)
635 {
636 int rc;
637 int token = rtas_token("set-indicator");
638
639 if (token == RTAS_UNKNOWN_SERVICE)
640 return -ENOENT;
641
642 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
643
644 WARN_ON(rc == -2 || (rc >= 9900 && rc <= 9905));
645
646 if (rc < 0)
647 return rtas_error_rc(rc);
648
649 return rc;
650 }
651
rtas_restart(char * cmd)652 void rtas_restart(char *cmd)
653 {
654 if (rtas_flash_term_hook)
655 rtas_flash_term_hook(SYS_RESTART);
656 printk("RTAS system-reboot returned %d\n",
657 rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
658 for (;;);
659 }
660
rtas_power_off(void)661 void rtas_power_off(void)
662 {
663 if (rtas_flash_term_hook)
664 rtas_flash_term_hook(SYS_POWER_OFF);
665 /* allow power on only with power button press */
666 printk("RTAS power-off returned %d\n",
667 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
668 for (;;);
669 }
670
rtas_halt(void)671 void rtas_halt(void)
672 {
673 if (rtas_flash_term_hook)
674 rtas_flash_term_hook(SYS_HALT);
675 /* allow power on only with power button press */
676 printk("RTAS power-off returned %d\n",
677 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
678 for (;;);
679 }
680
681 /* Must be in the RMO region, so we place it here */
682 static char rtas_os_term_buf[2048];
683
rtas_os_term(char * str)684 void rtas_os_term(char *str)
685 {
686 int status;
687
688 /*
689 * Firmware with the ibm,extended-os-term property is guaranteed
690 * to always return from an ibm,os-term call. Earlier versions without
691 * this property may terminate the partition which we want to avoid
692 * since it interferes with panic_timeout.
693 */
694 if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
695 RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
696 return;
697
698 snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
699
700 do {
701 status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
702 __pa(rtas_os_term_buf));
703 } while (rtas_busy_delay(status));
704
705 if (status != 0)
706 printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
707 }
708
709 static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
710 #ifdef CONFIG_PPC_PSERIES
__rtas_suspend_last_cpu(struct rtas_suspend_me_data * data,int wake_when_done)711 static int __rtas_suspend_last_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
712 {
713 u16 slb_size = mmu_slb_size;
714 int rc = H_MULTI_THREADS_ACTIVE;
715 int cpu;
716
717 slb_set_size(SLB_MIN_SIZE);
718 printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n", smp_processor_id());
719
720 while (rc == H_MULTI_THREADS_ACTIVE && !atomic_read(&data->done) &&
721 !atomic_read(&data->error))
722 rc = rtas_call(data->token, 0, 1, NULL);
723
724 if (rc || atomic_read(&data->error)) {
725 printk(KERN_DEBUG "ibm,suspend-me returned %d\n", rc);
726 slb_set_size(slb_size);
727 }
728
729 if (atomic_read(&data->error))
730 rc = atomic_read(&data->error);
731
732 atomic_set(&data->error, rc);
733 pSeries_coalesce_init();
734
735 if (wake_when_done) {
736 atomic_set(&data->done, 1);
737
738 for_each_online_cpu(cpu)
739 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
740 }
741
742 if (atomic_dec_return(&data->working) == 0)
743 complete(data->complete);
744
745 return rc;
746 }
747
rtas_suspend_last_cpu(struct rtas_suspend_me_data * data)748 int rtas_suspend_last_cpu(struct rtas_suspend_me_data *data)
749 {
750 atomic_inc(&data->working);
751 return __rtas_suspend_last_cpu(data, 0);
752 }
753
__rtas_suspend_cpu(struct rtas_suspend_me_data * data,int wake_when_done)754 static int __rtas_suspend_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
755 {
756 long rc = H_SUCCESS;
757 unsigned long msr_save;
758 int cpu;
759
760 atomic_inc(&data->working);
761
762 /* really need to ensure MSR.EE is off for H_JOIN */
763 msr_save = mfmsr();
764 mtmsr(msr_save & ~(MSR_EE));
765
766 while (rc == H_SUCCESS && !atomic_read(&data->done) && !atomic_read(&data->error))
767 rc = plpar_hcall_norets(H_JOIN);
768
769 mtmsr(msr_save);
770
771 if (rc == H_SUCCESS) {
772 /* This cpu was prodded and the suspend is complete. */
773 goto out;
774 } else if (rc == H_CONTINUE) {
775 /* All other cpus are in H_JOIN, this cpu does
776 * the suspend.
777 */
778 return __rtas_suspend_last_cpu(data, wake_when_done);
779 } else {
780 printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
781 smp_processor_id(), rc);
782 atomic_set(&data->error, rc);
783 }
784
785 if (wake_when_done) {
786 atomic_set(&data->done, 1);
787
788 /* This cpu did the suspend or got an error; in either case,
789 * we need to prod all other other cpus out of join state.
790 * Extra prods are harmless.
791 */
792 for_each_online_cpu(cpu)
793 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
794 }
795 out:
796 if (atomic_dec_return(&data->working) == 0)
797 complete(data->complete);
798 return rc;
799 }
800
rtas_suspend_cpu(struct rtas_suspend_me_data * data)801 int rtas_suspend_cpu(struct rtas_suspend_me_data *data)
802 {
803 return __rtas_suspend_cpu(data, 0);
804 }
805
rtas_percpu_suspend_me(void * info)806 static void rtas_percpu_suspend_me(void *info)
807 {
808 __rtas_suspend_cpu((struct rtas_suspend_me_data *)info, 1);
809 }
810
811 enum rtas_cpu_state {
812 DOWN,
813 UP,
814 };
815
816 #ifndef CONFIG_SMP
rtas_cpu_state_change_mask(enum rtas_cpu_state state,cpumask_var_t cpus)817 static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
818 cpumask_var_t cpus)
819 {
820 if (!cpumask_empty(cpus)) {
821 cpumask_clear(cpus);
822 return -EINVAL;
823 } else
824 return 0;
825 }
826 #else
827 /* On return cpumask will be altered to indicate CPUs changed.
828 * CPUs with states changed will be set in the mask,
829 * CPUs with status unchanged will be unset in the mask. */
rtas_cpu_state_change_mask(enum rtas_cpu_state state,cpumask_var_t cpus)830 static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
831 cpumask_var_t cpus)
832 {
833 int cpu;
834 int cpuret = 0;
835 int ret = 0;
836
837 if (cpumask_empty(cpus))
838 return 0;
839
840 for_each_cpu(cpu, cpus) {
841 switch (state) {
842 case DOWN:
843 cpuret = cpu_down(cpu);
844 break;
845 case UP:
846 cpuret = cpu_up(cpu);
847 break;
848 }
849 if (cpuret) {
850 pr_debug("%s: cpu_%s for cpu#%d returned %d.\n",
851 __func__,
852 ((state == UP) ? "up" : "down"),
853 cpu, cpuret);
854 if (!ret)
855 ret = cpuret;
856 if (state == UP) {
857 /* clear bits for unchanged cpus, return */
858 cpumask_shift_right(cpus, cpus, cpu);
859 cpumask_shift_left(cpus, cpus, cpu);
860 break;
861 } else {
862 /* clear bit for unchanged cpu, continue */
863 cpumask_clear_cpu(cpu, cpus);
864 }
865 }
866 }
867
868 return ret;
869 }
870 #endif
871
rtas_online_cpus_mask(cpumask_var_t cpus)872 int rtas_online_cpus_mask(cpumask_var_t cpus)
873 {
874 int ret;
875
876 ret = rtas_cpu_state_change_mask(UP, cpus);
877
878 if (ret) {
879 cpumask_var_t tmp_mask;
880
881 if (!alloc_cpumask_var(&tmp_mask, GFP_TEMPORARY))
882 return ret;
883
884 /* Use tmp_mask to preserve cpus mask from first failure */
885 cpumask_copy(tmp_mask, cpus);
886 rtas_offline_cpus_mask(tmp_mask);
887 free_cpumask_var(tmp_mask);
888 }
889
890 return ret;
891 }
892 EXPORT_SYMBOL(rtas_online_cpus_mask);
893
rtas_offline_cpus_mask(cpumask_var_t cpus)894 int rtas_offline_cpus_mask(cpumask_var_t cpus)
895 {
896 return rtas_cpu_state_change_mask(DOWN, cpus);
897 }
898 EXPORT_SYMBOL(rtas_offline_cpus_mask);
899
rtas_ibm_suspend_me(struct rtas_args * args)900 int rtas_ibm_suspend_me(struct rtas_args *args)
901 {
902 long state;
903 long rc;
904 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
905 struct rtas_suspend_me_data data;
906 DECLARE_COMPLETION_ONSTACK(done);
907 cpumask_var_t offline_mask;
908 int cpuret;
909
910 if (!rtas_service_present("ibm,suspend-me"))
911 return -ENOSYS;
912
913 /* Make sure the state is valid */
914 rc = plpar_hcall(H_VASI_STATE, retbuf,
915 ((u64)args->args[0] << 32) | args->args[1]);
916
917 state = retbuf[0];
918
919 if (rc) {
920 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
921 return rc;
922 } else if (state == H_VASI_ENABLED) {
923 args->args[args->nargs] = RTAS_NOT_SUSPENDABLE;
924 return 0;
925 } else if (state != H_VASI_SUSPENDING) {
926 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
927 state);
928 args->args[args->nargs] = -1;
929 return 0;
930 }
931
932 if (!alloc_cpumask_var(&offline_mask, GFP_TEMPORARY))
933 return -ENOMEM;
934
935 atomic_set(&data.working, 0);
936 atomic_set(&data.done, 0);
937 atomic_set(&data.error, 0);
938 data.token = rtas_token("ibm,suspend-me");
939 data.complete = &done;
940
941 /* All present CPUs must be online */
942 cpumask_andnot(offline_mask, cpu_present_mask, cpu_online_mask);
943 cpuret = rtas_online_cpus_mask(offline_mask);
944 if (cpuret) {
945 pr_err("%s: Could not bring present CPUs online.\n", __func__);
946 atomic_set(&data.error, cpuret);
947 goto out;
948 }
949
950 stop_topology_update();
951
952 /* Call function on all CPUs. One of us will make the
953 * rtas call
954 */
955 if (on_each_cpu(rtas_percpu_suspend_me, &data, 0))
956 atomic_set(&data.error, -EINVAL);
957
958 wait_for_completion(&done);
959
960 if (atomic_read(&data.error) != 0)
961 printk(KERN_ERR "Error doing global join\n");
962
963 start_topology_update();
964
965 /* Take down CPUs not online prior to suspend */
966 cpuret = rtas_offline_cpus_mask(offline_mask);
967 if (cpuret)
968 pr_warn("%s: Could not restore CPUs to offline state.\n",
969 __func__);
970
971 out:
972 free_cpumask_var(offline_mask);
973 return atomic_read(&data.error);
974 }
975 #else /* CONFIG_PPC_PSERIES */
rtas_ibm_suspend_me(struct rtas_args * args)976 int rtas_ibm_suspend_me(struct rtas_args *args)
977 {
978 return -ENOSYS;
979 }
980 #endif
981
982 /**
983 * Find a specific pseries error log in an RTAS extended event log.
984 * @log: RTAS error/event log
985 * @section_id: two character section identifier
986 *
987 * Returns a pointer to the specified errorlog or NULL if not found.
988 */
get_pseries_errorlog(struct rtas_error_log * log,uint16_t section_id)989 struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
990 uint16_t section_id)
991 {
992 struct rtas_ext_event_log_v6 *ext_log =
993 (struct rtas_ext_event_log_v6 *)log->buffer;
994 struct pseries_errorlog *sect;
995 unsigned char *p, *log_end;
996
997 /* Check that we understand the format */
998 if (log->extended_log_length < sizeof(struct rtas_ext_event_log_v6) ||
999 ext_log->log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
1000 ext_log->company_id != RTAS_V6EXT_COMPANY_ID_IBM)
1001 return NULL;
1002
1003 log_end = log->buffer + log->extended_log_length;
1004 p = ext_log->vendor_log;
1005
1006 while (p < log_end) {
1007 sect = (struct pseries_errorlog *)p;
1008 if (sect->id == section_id)
1009 return sect;
1010 p += sect->length;
1011 }
1012
1013 return NULL;
1014 }
1015
ppc_rtas(struct rtas_args __user * uargs)1016 asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
1017 {
1018 struct rtas_args args;
1019 unsigned long flags;
1020 char *buff_copy, *errbuf = NULL;
1021 int nargs;
1022 int rc;
1023
1024 if (!capable(CAP_SYS_ADMIN))
1025 return -EPERM;
1026
1027 if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
1028 return -EFAULT;
1029
1030 nargs = args.nargs;
1031 if (nargs > ARRAY_SIZE(args.args)
1032 || args.nret > ARRAY_SIZE(args.args)
1033 || nargs + args.nret > ARRAY_SIZE(args.args))
1034 return -EINVAL;
1035
1036 /* Copy in args. */
1037 if (copy_from_user(args.args, uargs->args,
1038 nargs * sizeof(rtas_arg_t)) != 0)
1039 return -EFAULT;
1040
1041 if (args.token == RTAS_UNKNOWN_SERVICE)
1042 return -EINVAL;
1043
1044 args.rets = &args.args[nargs];
1045 memset(args.rets, 0, args.nret * sizeof(rtas_arg_t));
1046
1047 /* Need to handle ibm,suspend_me call specially */
1048 if (args.token == ibm_suspend_me_token) {
1049 rc = rtas_ibm_suspend_me(&args);
1050 if (rc)
1051 return rc;
1052 goto copy_return;
1053 }
1054
1055 buff_copy = get_errorlog_buffer();
1056
1057 flags = lock_rtas();
1058
1059 rtas.args = args;
1060 enter_rtas(__pa(&rtas.args));
1061 args = rtas.args;
1062
1063 /* A -1 return code indicates that the last command couldn't
1064 be completed due to a hardware error. */
1065 if (args.rets[0] == -1)
1066 errbuf = __fetch_rtas_last_error(buff_copy);
1067
1068 unlock_rtas(flags);
1069
1070 if (buff_copy) {
1071 if (errbuf)
1072 log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
1073 kfree(buff_copy);
1074 }
1075
1076 copy_return:
1077 /* Copy out args. */
1078 if (copy_to_user(uargs->args + nargs,
1079 args.args + nargs,
1080 args.nret * sizeof(rtas_arg_t)) != 0)
1081 return -EFAULT;
1082
1083 return 0;
1084 }
1085
1086 /*
1087 * Call early during boot, before mem init or bootmem, to retrieve the RTAS
1088 * informations from the device-tree and allocate the RMO buffer for userland
1089 * accesses.
1090 */
rtas_initialize(void)1091 void __init rtas_initialize(void)
1092 {
1093 unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
1094
1095 /* Get RTAS dev node and fill up our "rtas" structure with infos
1096 * about it.
1097 */
1098 rtas.dev = of_find_node_by_name(NULL, "rtas");
1099 if (rtas.dev) {
1100 const u32 *basep, *entryp, *sizep;
1101
1102 basep = of_get_property(rtas.dev, "linux,rtas-base", NULL);
1103 sizep = of_get_property(rtas.dev, "rtas-size", NULL);
1104 if (basep != NULL && sizep != NULL) {
1105 rtas.base = *basep;
1106 rtas.size = *sizep;
1107 entryp = of_get_property(rtas.dev,
1108 "linux,rtas-entry", NULL);
1109 if (entryp == NULL) /* Ugh */
1110 rtas.entry = rtas.base;
1111 else
1112 rtas.entry = *entryp;
1113 } else
1114 rtas.dev = NULL;
1115 }
1116 if (!rtas.dev)
1117 return;
1118
1119 /* If RTAS was found, allocate the RMO buffer for it and look for
1120 * the stop-self token if any
1121 */
1122 #ifdef CONFIG_PPC64
1123 if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
1124 rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
1125 ibm_suspend_me_token = rtas_token("ibm,suspend-me");
1126 }
1127 #endif
1128 rtas_rmo_buf = memblock_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
1129
1130 #ifdef CONFIG_RTAS_ERROR_LOGGING
1131 rtas_last_error_token = rtas_token("rtas-last-error");
1132 #endif
1133 }
1134
early_init_dt_scan_rtas(unsigned long node,const char * uname,int depth,void * data)1135 int __init early_init_dt_scan_rtas(unsigned long node,
1136 const char *uname, int depth, void *data)
1137 {
1138 u32 *basep, *entryp, *sizep;
1139
1140 if (depth != 1 || strcmp(uname, "rtas") != 0)
1141 return 0;
1142
1143 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
1144 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
1145 sizep = of_get_flat_dt_prop(node, "rtas-size", NULL);
1146
1147 if (basep && entryp && sizep) {
1148 rtas.base = *basep;
1149 rtas.entry = *entryp;
1150 rtas.size = *sizep;
1151 }
1152
1153 #ifdef CONFIG_UDBG_RTAS_CONSOLE
1154 basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1155 if (basep)
1156 rtas_putchar_token = *basep;
1157
1158 basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1159 if (basep)
1160 rtas_getchar_token = *basep;
1161
1162 if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1163 rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1164 udbg_init_rtas_console();
1165
1166 #endif
1167
1168 /* break now */
1169 return 1;
1170 }
1171
1172 static arch_spinlock_t timebase_lock;
1173 static u64 timebase = 0;
1174
rtas_give_timebase(void)1175 void __cpuinit rtas_give_timebase(void)
1176 {
1177 unsigned long flags;
1178
1179 local_irq_save(flags);
1180 hard_irq_disable();
1181 arch_spin_lock(&timebase_lock);
1182 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1183 timebase = get_tb();
1184 arch_spin_unlock(&timebase_lock);
1185
1186 while (timebase)
1187 barrier();
1188 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1189 local_irq_restore(flags);
1190 }
1191
rtas_take_timebase(void)1192 void __cpuinit rtas_take_timebase(void)
1193 {
1194 while (!timebase)
1195 barrier();
1196 arch_spin_lock(&timebase_lock);
1197 set_tb(timebase >> 32, timebase & 0xffffffff);
1198 timebase = 0;
1199 arch_spin_unlock(&timebase_lock);
1200 }
1201