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(unsigned char c)94 static void call_rtas_display_status(unsigned 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 = cpu_to_be32(10);
104 args->nargs = cpu_to_be32(1);
105 args->nret = cpu_to_be32(1);
106 args->rets = &(args->args[1]);
107 args->args[0] = cpu_to_be32(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 __be32 *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 = be32_to_cpu(*p);
225 if ((p = of_get_property(root,
226 "ibm,form-feed", NULL)))
227 form_feed = be32_to_cpu(*p);
228 if ((p = of_get_property(root,
229 "ibm,display-number-of-lines", NULL)))
230 display_lines = be32_to_cpu(*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 __be32 *tokp;
326 if (rtas.dev == NULL)
327 return RTAS_UNKNOWN_SERVICE;
328 tokp = of_get_property(rtas.dev, service, NULL);
329 return tokp ? be32_to_cpu(*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 = cpu_to_be32(rtas_last_error_token);
384 err_args.nargs = cpu_to_be32(2);
385 err_args.nret = cpu_to_be32(1);
386 err_args.args[0] = cpu_to_be32(__pa(rtas_err_buf));
387 err_args.args[1] = cpu_to_be32(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 (slab_is_available())
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 = cpu_to_be32(token);
437 rtas_args->nargs = cpu_to_be32(nargs);
438 rtas_args->nret = cpu_to_be32(nret);
439 rtas_args->rets = &(rtas_args->args[nargs]);
440 va_start(list, outputs);
441 for (i = 0; i < nargs; ++i)
442 rtas_args->args[i] = cpu_to_be32(va_arg(list, __u32));
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 (be32_to_cpu(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] = be32_to_cpu(rtas_args->rets[i+1]);
458 ret = (nret > 0)? be32_to_cpu(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 (slab_is_available())
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 >= RTAS_EXTENDED_DELAY_MIN &&
482 status <= RTAS_EXTENDED_DELAY_MAX) {
483 order = status - RTAS_EXTENDED_DELAY_MIN;
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_get_sensor_fast(int sensor,int index,int * state)588 int rtas_get_sensor_fast(int sensor, int index, int *state)
589 {
590 int token = rtas_token("get-sensor-state");
591 int rc;
592
593 if (token == RTAS_UNKNOWN_SERVICE)
594 return -ENOENT;
595
596 rc = rtas_call(token, 2, 2, state, sensor, index);
597 WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
598 rc <= RTAS_EXTENDED_DELAY_MAX));
599
600 if (rc < 0)
601 return rtas_error_rc(rc);
602 return rc;
603 }
604
rtas_indicator_present(int token,int * maxindex)605 bool rtas_indicator_present(int token, int *maxindex)
606 {
607 int proplen, count, i;
608 const struct indicator_elem {
609 __be32 token;
610 __be32 maxindex;
611 } *indicators;
612
613 indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
614 if (!indicators)
615 return false;
616
617 count = proplen / sizeof(struct indicator_elem);
618
619 for (i = 0; i < count; i++) {
620 if (__be32_to_cpu(indicators[i].token) != token)
621 continue;
622 if (maxindex)
623 *maxindex = __be32_to_cpu(indicators[i].maxindex);
624 return true;
625 }
626
627 return false;
628 }
629 EXPORT_SYMBOL(rtas_indicator_present);
630
rtas_set_indicator(int indicator,int index,int new_value)631 int rtas_set_indicator(int indicator, int index, int new_value)
632 {
633 int token = rtas_token("set-indicator");
634 int rc;
635
636 if (token == RTAS_UNKNOWN_SERVICE)
637 return -ENOENT;
638
639 do {
640 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
641 } while (rtas_busy_delay(rc));
642
643 if (rc < 0)
644 return rtas_error_rc(rc);
645 return rc;
646 }
647 EXPORT_SYMBOL(rtas_set_indicator);
648
649 /*
650 * Ignoring RTAS extended delay
651 */
rtas_set_indicator_fast(int indicator,int index,int new_value)652 int rtas_set_indicator_fast(int indicator, int index, int new_value)
653 {
654 int rc;
655 int token = rtas_token("set-indicator");
656
657 if (token == RTAS_UNKNOWN_SERVICE)
658 return -ENOENT;
659
660 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
661
662 WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
663 rc <= RTAS_EXTENDED_DELAY_MAX));
664
665 if (rc < 0)
666 return rtas_error_rc(rc);
667
668 return rc;
669 }
670
rtas_restart(char * cmd)671 void rtas_restart(char *cmd)
672 {
673 if (rtas_flash_term_hook)
674 rtas_flash_term_hook(SYS_RESTART);
675 printk("RTAS system-reboot returned %d\n",
676 rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
677 for (;;);
678 }
679
rtas_power_off(void)680 void rtas_power_off(void)
681 {
682 if (rtas_flash_term_hook)
683 rtas_flash_term_hook(SYS_POWER_OFF);
684 /* allow power on only with power button press */
685 printk("RTAS power-off returned %d\n",
686 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
687 for (;;);
688 }
689
rtas_halt(void)690 void rtas_halt(void)
691 {
692 if (rtas_flash_term_hook)
693 rtas_flash_term_hook(SYS_HALT);
694 /* allow power on only with power button press */
695 printk("RTAS power-off returned %d\n",
696 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
697 for (;;);
698 }
699
700 /* Must be in the RMO region, so we place it here */
701 static char rtas_os_term_buf[2048];
702
rtas_os_term(char * str)703 void rtas_os_term(char *str)
704 {
705 int status;
706
707 /*
708 * Firmware with the ibm,extended-os-term property is guaranteed
709 * to always return from an ibm,os-term call. Earlier versions without
710 * this property may terminate the partition which we want to avoid
711 * since it interferes with panic_timeout.
712 */
713 if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
714 RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
715 return;
716
717 snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
718
719 do {
720 status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
721 __pa(rtas_os_term_buf));
722 } while (rtas_busy_delay(status));
723
724 if (status != 0)
725 printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
726 }
727
728 static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
729 #ifdef CONFIG_PPC_PSERIES
__rtas_suspend_last_cpu(struct rtas_suspend_me_data * data,int wake_when_done)730 static int __rtas_suspend_last_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
731 {
732 u16 slb_size = mmu_slb_size;
733 int rc = H_MULTI_THREADS_ACTIVE;
734 int cpu;
735
736 slb_set_size(SLB_MIN_SIZE);
737 printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n", smp_processor_id());
738
739 while (rc == H_MULTI_THREADS_ACTIVE && !atomic_read(&data->done) &&
740 !atomic_read(&data->error))
741 rc = rtas_call(data->token, 0, 1, NULL);
742
743 if (rc || atomic_read(&data->error)) {
744 printk(KERN_DEBUG "ibm,suspend-me returned %d\n", rc);
745 slb_set_size(slb_size);
746 }
747
748 if (atomic_read(&data->error))
749 rc = atomic_read(&data->error);
750
751 atomic_set(&data->error, rc);
752 pSeries_coalesce_init();
753
754 if (wake_when_done) {
755 atomic_set(&data->done, 1);
756
757 for_each_online_cpu(cpu)
758 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
759 }
760
761 if (atomic_dec_return(&data->working) == 0)
762 complete(data->complete);
763
764 return rc;
765 }
766
rtas_suspend_last_cpu(struct rtas_suspend_me_data * data)767 int rtas_suspend_last_cpu(struct rtas_suspend_me_data *data)
768 {
769 atomic_inc(&data->working);
770 return __rtas_suspend_last_cpu(data, 0);
771 }
772
__rtas_suspend_cpu(struct rtas_suspend_me_data * data,int wake_when_done)773 static int __rtas_suspend_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
774 {
775 long rc = H_SUCCESS;
776 unsigned long msr_save;
777 int cpu;
778
779 atomic_inc(&data->working);
780
781 /* really need to ensure MSR.EE is off for H_JOIN */
782 msr_save = mfmsr();
783 mtmsr(msr_save & ~(MSR_EE));
784
785 while (rc == H_SUCCESS && !atomic_read(&data->done) && !atomic_read(&data->error))
786 rc = plpar_hcall_norets(H_JOIN);
787
788 mtmsr(msr_save);
789
790 if (rc == H_SUCCESS) {
791 /* This cpu was prodded and the suspend is complete. */
792 goto out;
793 } else if (rc == H_CONTINUE) {
794 /* All other cpus are in H_JOIN, this cpu does
795 * the suspend.
796 */
797 return __rtas_suspend_last_cpu(data, wake_when_done);
798 } else {
799 printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
800 smp_processor_id(), rc);
801 atomic_set(&data->error, rc);
802 }
803
804 if (wake_when_done) {
805 atomic_set(&data->done, 1);
806
807 /* This cpu did the suspend or got an error; in either case,
808 * we need to prod all other other cpus out of join state.
809 * Extra prods are harmless.
810 */
811 for_each_online_cpu(cpu)
812 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
813 }
814 out:
815 if (atomic_dec_return(&data->working) == 0)
816 complete(data->complete);
817 return rc;
818 }
819
rtas_suspend_cpu(struct rtas_suspend_me_data * data)820 int rtas_suspend_cpu(struct rtas_suspend_me_data *data)
821 {
822 return __rtas_suspend_cpu(data, 0);
823 }
824
rtas_percpu_suspend_me(void * info)825 static void rtas_percpu_suspend_me(void *info)
826 {
827 __rtas_suspend_cpu((struct rtas_suspend_me_data *)info, 1);
828 }
829
830 enum rtas_cpu_state {
831 DOWN,
832 UP,
833 };
834
835 #ifndef CONFIG_SMP
rtas_cpu_state_change_mask(enum rtas_cpu_state state,cpumask_var_t cpus)836 static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
837 cpumask_var_t cpus)
838 {
839 if (!cpumask_empty(cpus)) {
840 cpumask_clear(cpus);
841 return -EINVAL;
842 } else
843 return 0;
844 }
845 #else
846 /* On return cpumask will be altered to indicate CPUs changed.
847 * CPUs with states changed will be set in the mask,
848 * CPUs with status unchanged will be unset in the mask. */
rtas_cpu_state_change_mask(enum rtas_cpu_state state,cpumask_var_t cpus)849 static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
850 cpumask_var_t cpus)
851 {
852 int cpu;
853 int cpuret = 0;
854 int ret = 0;
855
856 if (cpumask_empty(cpus))
857 return 0;
858
859 for_each_cpu(cpu, cpus) {
860 struct device *dev = get_cpu_device(cpu);
861
862 switch (state) {
863 case DOWN:
864 cpuret = device_offline(dev);
865 break;
866 case UP:
867 cpuret = device_online(dev);
868 break;
869 }
870 if (cpuret < 0) {
871 pr_debug("%s: cpu_%s for cpu#%d returned %d.\n",
872 __func__,
873 ((state == UP) ? "up" : "down"),
874 cpu, cpuret);
875 if (!ret)
876 ret = cpuret;
877 if (state == UP) {
878 /* clear bits for unchanged cpus, return */
879 cpumask_shift_right(cpus, cpus, cpu);
880 cpumask_shift_left(cpus, cpus, cpu);
881 break;
882 } else {
883 /* clear bit for unchanged cpu, continue */
884 cpumask_clear_cpu(cpu, cpus);
885 }
886 }
887 }
888
889 return ret;
890 }
891 #endif
892
rtas_online_cpus_mask(cpumask_var_t cpus)893 int rtas_online_cpus_mask(cpumask_var_t cpus)
894 {
895 int ret;
896
897 ret = rtas_cpu_state_change_mask(UP, cpus);
898
899 if (ret) {
900 cpumask_var_t tmp_mask;
901
902 if (!alloc_cpumask_var(&tmp_mask, GFP_TEMPORARY))
903 return ret;
904
905 /* Use tmp_mask to preserve cpus mask from first failure */
906 cpumask_copy(tmp_mask, cpus);
907 rtas_offline_cpus_mask(tmp_mask);
908 free_cpumask_var(tmp_mask);
909 }
910
911 return ret;
912 }
913 EXPORT_SYMBOL(rtas_online_cpus_mask);
914
rtas_offline_cpus_mask(cpumask_var_t cpus)915 int rtas_offline_cpus_mask(cpumask_var_t cpus)
916 {
917 return rtas_cpu_state_change_mask(DOWN, cpus);
918 }
919 EXPORT_SYMBOL(rtas_offline_cpus_mask);
920
rtas_ibm_suspend_me(u64 handle)921 int rtas_ibm_suspend_me(u64 handle)
922 {
923 long state;
924 long rc;
925 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
926 struct rtas_suspend_me_data data;
927 DECLARE_COMPLETION_ONSTACK(done);
928 cpumask_var_t offline_mask;
929 int cpuret;
930
931 if (!rtas_service_present("ibm,suspend-me"))
932 return -ENOSYS;
933
934 /* Make sure the state is valid */
935 rc = plpar_hcall(H_VASI_STATE, retbuf, handle);
936
937 state = retbuf[0];
938
939 if (rc) {
940 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
941 return rc;
942 } else if (state == H_VASI_ENABLED) {
943 return -EAGAIN;
944 } else if (state != H_VASI_SUSPENDING) {
945 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
946 state);
947 return -EIO;
948 }
949
950 if (!alloc_cpumask_var(&offline_mask, GFP_TEMPORARY))
951 return -ENOMEM;
952
953 atomic_set(&data.working, 0);
954 atomic_set(&data.done, 0);
955 atomic_set(&data.error, 0);
956 data.token = rtas_token("ibm,suspend-me");
957 data.complete = &done;
958
959 lock_device_hotplug();
960
961 /* All present CPUs must be online */
962 cpumask_andnot(offline_mask, cpu_present_mask, cpu_online_mask);
963 cpuret = rtas_online_cpus_mask(offline_mask);
964 if (cpuret) {
965 pr_err("%s: Could not bring present CPUs online.\n", __func__);
966 atomic_set(&data.error, cpuret);
967 goto out;
968 }
969
970 cpu_hotplug_disable();
971 stop_topology_update();
972
973 /* Call function on all CPUs. One of us will make the
974 * rtas call
975 */
976 if (on_each_cpu(rtas_percpu_suspend_me, &data, 0))
977 atomic_set(&data.error, -EINVAL);
978
979 wait_for_completion(&done);
980
981 if (atomic_read(&data.error) != 0)
982 printk(KERN_ERR "Error doing global join\n");
983
984 start_topology_update();
985 cpu_hotplug_enable();
986
987 /* Take down CPUs not online prior to suspend */
988 cpuret = rtas_offline_cpus_mask(offline_mask);
989 if (cpuret)
990 pr_warn("%s: Could not restore CPUs to offline state.\n",
991 __func__);
992
993 out:
994 unlock_device_hotplug();
995 free_cpumask_var(offline_mask);
996 return atomic_read(&data.error);
997 }
998 #else /* CONFIG_PPC_PSERIES */
rtas_ibm_suspend_me(u64 handle)999 int rtas_ibm_suspend_me(u64 handle)
1000 {
1001 return -ENOSYS;
1002 }
1003 #endif
1004
1005 /**
1006 * Find a specific pseries error log in an RTAS extended event log.
1007 * @log: RTAS error/event log
1008 * @section_id: two character section identifier
1009 *
1010 * Returns a pointer to the specified errorlog or NULL if not found.
1011 */
get_pseries_errorlog(struct rtas_error_log * log,uint16_t section_id)1012 struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
1013 uint16_t section_id)
1014 {
1015 struct rtas_ext_event_log_v6 *ext_log =
1016 (struct rtas_ext_event_log_v6 *)log->buffer;
1017 struct pseries_errorlog *sect;
1018 unsigned char *p, *log_end;
1019 uint32_t ext_log_length = rtas_error_extended_log_length(log);
1020 uint8_t log_format = rtas_ext_event_log_format(ext_log);
1021 uint32_t company_id = rtas_ext_event_company_id(ext_log);
1022
1023 /* Check that we understand the format */
1024 if (ext_log_length < sizeof(struct rtas_ext_event_log_v6) ||
1025 log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
1026 company_id != RTAS_V6EXT_COMPANY_ID_IBM)
1027 return NULL;
1028
1029 log_end = log->buffer + ext_log_length;
1030 p = ext_log->vendor_log;
1031
1032 while (p < log_end) {
1033 sect = (struct pseries_errorlog *)p;
1034 if (pseries_errorlog_id(sect) == section_id)
1035 return sect;
1036 p += pseries_errorlog_length(sect);
1037 }
1038
1039 return NULL;
1040 }
1041
1042 /* We assume to be passed big endian arguments */
ppc_rtas(struct rtas_args __user * uargs)1043 asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
1044 {
1045 struct rtas_args args;
1046 unsigned long flags;
1047 char *buff_copy, *errbuf = NULL;
1048 int nargs, nret, token;
1049
1050 if (!capable(CAP_SYS_ADMIN))
1051 return -EPERM;
1052
1053 if (!rtas.entry)
1054 return -EINVAL;
1055
1056 if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
1057 return -EFAULT;
1058
1059 nargs = be32_to_cpu(args.nargs);
1060 nret = be32_to_cpu(args.nret);
1061 token = be32_to_cpu(args.token);
1062
1063 if (nargs > ARRAY_SIZE(args.args)
1064 || nret > ARRAY_SIZE(args.args)
1065 || nargs + nret > ARRAY_SIZE(args.args))
1066 return -EINVAL;
1067
1068 /* Copy in args. */
1069 if (copy_from_user(args.args, uargs->args,
1070 nargs * sizeof(rtas_arg_t)) != 0)
1071 return -EFAULT;
1072
1073 if (token == RTAS_UNKNOWN_SERVICE)
1074 return -EINVAL;
1075
1076 args.rets = &args.args[nargs];
1077 memset(args.rets, 0, nret * sizeof(rtas_arg_t));
1078
1079 /* Need to handle ibm,suspend_me call specially */
1080 if (token == ibm_suspend_me_token) {
1081
1082 /*
1083 * rtas_ibm_suspend_me assumes the streamid handle is in cpu
1084 * endian, or at least the hcall within it requires it.
1085 */
1086 int rc = 0;
1087 u64 handle = ((u64)be32_to_cpu(args.args[0]) << 32)
1088 | be32_to_cpu(args.args[1]);
1089 rc = rtas_ibm_suspend_me(handle);
1090 if (rc == -EAGAIN)
1091 args.rets[0] = cpu_to_be32(RTAS_NOT_SUSPENDABLE);
1092 else if (rc == -EIO)
1093 args.rets[0] = cpu_to_be32(-1);
1094 else if (rc)
1095 return rc;
1096 goto copy_return;
1097 }
1098
1099 buff_copy = get_errorlog_buffer();
1100
1101 flags = lock_rtas();
1102
1103 rtas.args = args;
1104 enter_rtas(__pa(&rtas.args));
1105 args = rtas.args;
1106
1107 /* A -1 return code indicates that the last command couldn't
1108 be completed due to a hardware error. */
1109 if (be32_to_cpu(args.rets[0]) == -1)
1110 errbuf = __fetch_rtas_last_error(buff_copy);
1111
1112 unlock_rtas(flags);
1113
1114 if (buff_copy) {
1115 if (errbuf)
1116 log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
1117 kfree(buff_copy);
1118 }
1119
1120 copy_return:
1121 /* Copy out args. */
1122 if (copy_to_user(uargs->args + nargs,
1123 args.args + nargs,
1124 nret * sizeof(rtas_arg_t)) != 0)
1125 return -EFAULT;
1126
1127 return 0;
1128 }
1129
1130 /*
1131 * Call early during boot, before mem init, to retrieve the RTAS
1132 * information from the device-tree and allocate the RMO buffer for userland
1133 * accesses.
1134 */
rtas_initialize(void)1135 void __init rtas_initialize(void)
1136 {
1137 unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
1138
1139 /* Get RTAS dev node and fill up our "rtas" structure with infos
1140 * about it.
1141 */
1142 rtas.dev = of_find_node_by_name(NULL, "rtas");
1143 if (rtas.dev) {
1144 const __be32 *basep, *entryp, *sizep;
1145
1146 basep = of_get_property(rtas.dev, "linux,rtas-base", NULL);
1147 sizep = of_get_property(rtas.dev, "rtas-size", NULL);
1148 if (basep != NULL && sizep != NULL) {
1149 rtas.base = __be32_to_cpu(*basep);
1150 rtas.size = __be32_to_cpu(*sizep);
1151 entryp = of_get_property(rtas.dev,
1152 "linux,rtas-entry", NULL);
1153 if (entryp == NULL) /* Ugh */
1154 rtas.entry = rtas.base;
1155 else
1156 rtas.entry = __be32_to_cpu(*entryp);
1157 } else
1158 rtas.dev = NULL;
1159 }
1160 if (!rtas.dev)
1161 return;
1162
1163 /* If RTAS was found, allocate the RMO buffer for it and look for
1164 * the stop-self token if any
1165 */
1166 #ifdef CONFIG_PPC64
1167 if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
1168 rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
1169 ibm_suspend_me_token = rtas_token("ibm,suspend-me");
1170 }
1171 #endif
1172 rtas_rmo_buf = memblock_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
1173
1174 #ifdef CONFIG_RTAS_ERROR_LOGGING
1175 rtas_last_error_token = rtas_token("rtas-last-error");
1176 #endif
1177 }
1178
early_init_dt_scan_rtas(unsigned long node,const char * uname,int depth,void * data)1179 int __init early_init_dt_scan_rtas(unsigned long node,
1180 const char *uname, int depth, void *data)
1181 {
1182 const u32 *basep, *entryp, *sizep;
1183
1184 if (depth != 1 || strcmp(uname, "rtas") != 0)
1185 return 0;
1186
1187 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
1188 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
1189 sizep = of_get_flat_dt_prop(node, "rtas-size", NULL);
1190
1191 if (basep && entryp && sizep) {
1192 rtas.base = *basep;
1193 rtas.entry = *entryp;
1194 rtas.size = *sizep;
1195 }
1196
1197 #ifdef CONFIG_UDBG_RTAS_CONSOLE
1198 basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1199 if (basep)
1200 rtas_putchar_token = *basep;
1201
1202 basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1203 if (basep)
1204 rtas_getchar_token = *basep;
1205
1206 if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1207 rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1208 udbg_init_rtas_console();
1209
1210 #endif
1211
1212 /* break now */
1213 return 1;
1214 }
1215
1216 static arch_spinlock_t timebase_lock;
1217 static u64 timebase = 0;
1218
rtas_give_timebase(void)1219 void rtas_give_timebase(void)
1220 {
1221 unsigned long flags;
1222
1223 local_irq_save(flags);
1224 hard_irq_disable();
1225 arch_spin_lock(&timebase_lock);
1226 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1227 timebase = get_tb();
1228 arch_spin_unlock(&timebase_lock);
1229
1230 while (timebase)
1231 barrier();
1232 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1233 local_irq_restore(flags);
1234 }
1235
rtas_take_timebase(void)1236 void rtas_take_timebase(void)
1237 {
1238 while (!timebase)
1239 barrier();
1240 arch_spin_lock(&timebase_lock);
1241 set_tb(timebase >> 32, timebase & 0xffffffff);
1242 timebase = 0;
1243 arch_spin_unlock(&timebase_lock);
1244 }
1245