Full support for Ginger Console
[linux-ginger.git] / arch / powerpc / kernel / rtas.c
blobbf90361bb70f3664fb02742bc3514f145207b26d
1 /*
3 * Procedures for interfacing to the RTAS on CHRP machines.
5 * Peter Bergner, IBM March 2001.
6 * Copyright (C) 2001 IBM.
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.
14 #include <stdarg.h>
15 #include <linux/kernel.h>
16 #include <linux/types.h>
17 #include <linux/spinlock.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/capability.h>
21 #include <linux/delay.h>
22 #include <linux/smp.h>
23 #include <linux/completion.h>
24 #include <linux/cpumask.h>
25 #include <linux/lmb.h>
27 #include <asm/prom.h>
28 #include <asm/rtas.h>
29 #include <asm/hvcall.h>
30 #include <asm/machdep.h>
31 #include <asm/firmware.h>
32 #include <asm/page.h>
33 #include <asm/param.h>
34 #include <asm/system.h>
35 #include <asm/delay.h>
36 #include <asm/uaccess.h>
37 #include <asm/udbg.h>
38 #include <asm/syscalls.h>
39 #include <asm/smp.h>
40 #include <asm/atomic.h>
41 #include <asm/time.h>
42 #include <asm/mmu.h>
44 struct rtas_t rtas = {
45 .lock = __RAW_SPIN_LOCK_UNLOCKED
47 EXPORT_SYMBOL(rtas);
49 struct rtas_suspend_me_data {
50 atomic_t working; /* number of cpus accessing this struct */
51 atomic_t done;
52 int token; /* ibm,suspend-me */
53 int error;
54 struct completion *complete; /* wait on this until working == 0 */
57 DEFINE_SPINLOCK(rtas_data_buf_lock);
58 EXPORT_SYMBOL(rtas_data_buf_lock);
60 char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
61 EXPORT_SYMBOL(rtas_data_buf);
63 unsigned long rtas_rmo_buf;
66 * If non-NULL, this gets called when the kernel terminates.
67 * This is done like this so rtas_flash can be a module.
69 void (*rtas_flash_term_hook)(int);
70 EXPORT_SYMBOL(rtas_flash_term_hook);
72 /* RTAS use home made raw locking instead of spin_lock_irqsave
73 * because those can be called from within really nasty contexts
74 * such as having the timebase stopped which would lockup with
75 * normal locks and spinlock debugging enabled
77 static unsigned long lock_rtas(void)
79 unsigned long flags;
81 local_irq_save(flags);
82 preempt_disable();
83 __raw_spin_lock_flags(&rtas.lock, flags);
84 return flags;
87 static void unlock_rtas(unsigned long flags)
89 __raw_spin_unlock(&rtas.lock);
90 local_irq_restore(flags);
91 preempt_enable();
95 * call_rtas_display_status and call_rtas_display_status_delay
96 * are designed only for very early low-level debugging, which
97 * is why the token is hard-coded to 10.
99 static void call_rtas_display_status(char c)
101 struct rtas_args *args = &rtas.args;
102 unsigned long s;
104 if (!rtas.base)
105 return;
106 s = lock_rtas();
108 args->token = 10;
109 args->nargs = 1;
110 args->nret = 1;
111 args->rets = (rtas_arg_t *)&(args->args[1]);
112 args->args[0] = (unsigned char)c;
114 enter_rtas(__pa(args));
116 unlock_rtas(s);
119 static void call_rtas_display_status_delay(char c)
121 static int pending_newline = 0; /* did last write end with unprinted newline? */
122 static int width = 16;
124 if (c == '\n') {
125 while (width-- > 0)
126 call_rtas_display_status(' ');
127 width = 16;
128 mdelay(500);
129 pending_newline = 1;
130 } else {
131 if (pending_newline) {
132 call_rtas_display_status('\r');
133 call_rtas_display_status('\n');
135 pending_newline = 0;
136 if (width--) {
137 call_rtas_display_status(c);
138 udelay(10000);
143 void __init udbg_init_rtas_panel(void)
145 udbg_putc = call_rtas_display_status_delay;
148 #ifdef CONFIG_UDBG_RTAS_CONSOLE
150 /* If you think you're dying before early_init_dt_scan_rtas() does its
151 * work, you can hard code the token values for your firmware here and
152 * hardcode rtas.base/entry etc.
154 static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
155 static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
157 static void udbg_rtascon_putc(char c)
159 int tries;
161 if (!rtas.base)
162 return;
164 /* Add CRs before LFs */
165 if (c == '\n')
166 udbg_rtascon_putc('\r');
168 /* if there is more than one character to be displayed, wait a bit */
169 for (tries = 0; tries < 16; tries++) {
170 if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
171 break;
172 udelay(1000);
176 static int udbg_rtascon_getc_poll(void)
178 int c;
180 if (!rtas.base)
181 return -1;
183 if (rtas_call(rtas_getchar_token, 0, 2, &c))
184 return -1;
186 return c;
189 static int udbg_rtascon_getc(void)
191 int c;
193 while ((c = udbg_rtascon_getc_poll()) == -1)
196 return c;
200 void __init udbg_init_rtas_console(void)
202 udbg_putc = udbg_rtascon_putc;
203 udbg_getc = udbg_rtascon_getc;
204 udbg_getc_poll = udbg_rtascon_getc_poll;
206 #endif /* CONFIG_UDBG_RTAS_CONSOLE */
208 void rtas_progress(char *s, unsigned short hex)
210 struct device_node *root;
211 int width;
212 const int *p;
213 char *os;
214 static int display_character, set_indicator;
215 static int display_width, display_lines, form_feed;
216 static const int *row_width;
217 static DEFINE_SPINLOCK(progress_lock);
218 static int current_line;
219 static int pending_newline = 0; /* did last write end with unprinted newline? */
221 if (!rtas.base)
222 return;
224 if (display_width == 0) {
225 display_width = 0x10;
226 if ((root = of_find_node_by_path("/rtas"))) {
227 if ((p = of_get_property(root,
228 "ibm,display-line-length", NULL)))
229 display_width = *p;
230 if ((p = of_get_property(root,
231 "ibm,form-feed", NULL)))
232 form_feed = *p;
233 if ((p = of_get_property(root,
234 "ibm,display-number-of-lines", NULL)))
235 display_lines = *p;
236 row_width = of_get_property(root,
237 "ibm,display-truncation-length", NULL);
238 of_node_put(root);
240 display_character = rtas_token("display-character");
241 set_indicator = rtas_token("set-indicator");
244 if (display_character == RTAS_UNKNOWN_SERVICE) {
245 /* use hex display if available */
246 if (set_indicator != RTAS_UNKNOWN_SERVICE)
247 rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
248 return;
251 spin_lock(&progress_lock);
254 * Last write ended with newline, but we didn't print it since
255 * it would just clear the bottom line of output. Print it now
256 * instead.
258 * If no newline is pending and form feed is supported, clear the
259 * display with a form feed; otherwise, print a CR to start output
260 * at the beginning of the line.
262 if (pending_newline) {
263 rtas_call(display_character, 1, 1, NULL, '\r');
264 rtas_call(display_character, 1, 1, NULL, '\n');
265 pending_newline = 0;
266 } else {
267 current_line = 0;
268 if (form_feed)
269 rtas_call(display_character, 1, 1, NULL,
270 (char)form_feed);
271 else
272 rtas_call(display_character, 1, 1, NULL, '\r');
275 if (row_width)
276 width = row_width[current_line];
277 else
278 width = display_width;
279 os = s;
280 while (*os) {
281 if (*os == '\n' || *os == '\r') {
282 /* If newline is the last character, save it
283 * until next call to avoid bumping up the
284 * display output.
286 if (*os == '\n' && !os[1]) {
287 pending_newline = 1;
288 current_line++;
289 if (current_line > display_lines-1)
290 current_line = display_lines-1;
291 spin_unlock(&progress_lock);
292 return;
295 /* RTAS wants CR-LF, not just LF */
297 if (*os == '\n') {
298 rtas_call(display_character, 1, 1, NULL, '\r');
299 rtas_call(display_character, 1, 1, NULL, '\n');
300 } else {
301 /* CR might be used to re-draw a line, so we'll
302 * leave it alone and not add LF.
304 rtas_call(display_character, 1, 1, NULL, *os);
307 if (row_width)
308 width = row_width[current_line];
309 else
310 width = display_width;
311 } else {
312 width--;
313 rtas_call(display_character, 1, 1, NULL, *os);
316 os++;
318 /* if we overwrite the screen length */
319 if (width <= 0)
320 while ((*os != 0) && (*os != '\n') && (*os != '\r'))
321 os++;
324 spin_unlock(&progress_lock);
326 EXPORT_SYMBOL(rtas_progress); /* needed by rtas_flash module */
328 int rtas_token(const char *service)
330 const int *tokp;
331 if (rtas.dev == NULL)
332 return RTAS_UNKNOWN_SERVICE;
333 tokp = of_get_property(rtas.dev, service, NULL);
334 return tokp ? *tokp : RTAS_UNKNOWN_SERVICE;
336 EXPORT_SYMBOL(rtas_token);
338 int rtas_service_present(const char *service)
340 return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
342 EXPORT_SYMBOL(rtas_service_present);
344 #ifdef CONFIG_RTAS_ERROR_LOGGING
346 * Return the firmware-specified size of the error log buffer
347 * for all rtas calls that require an error buffer argument.
348 * This includes 'check-exception' and 'rtas-last-error'.
350 int rtas_get_error_log_max(void)
352 static int rtas_error_log_max;
353 if (rtas_error_log_max)
354 return rtas_error_log_max;
356 rtas_error_log_max = rtas_token ("rtas-error-log-max");
357 if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
358 (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
359 printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
360 rtas_error_log_max);
361 rtas_error_log_max = RTAS_ERROR_LOG_MAX;
363 return rtas_error_log_max;
365 EXPORT_SYMBOL(rtas_get_error_log_max);
368 static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
369 static int rtas_last_error_token;
371 /** Return a copy of the detailed error text associated with the
372 * most recent failed call to rtas. Because the error text
373 * might go stale if there are any other intervening rtas calls,
374 * this routine must be called atomically with whatever produced
375 * the error (i.e. with rtas.lock still held from the previous call).
377 static char *__fetch_rtas_last_error(char *altbuf)
379 struct rtas_args err_args, save_args;
380 u32 bufsz;
381 char *buf = NULL;
383 if (rtas_last_error_token == -1)
384 return NULL;
386 bufsz = rtas_get_error_log_max();
388 err_args.token = rtas_last_error_token;
389 err_args.nargs = 2;
390 err_args.nret = 1;
391 err_args.args[0] = (rtas_arg_t)__pa(rtas_err_buf);
392 err_args.args[1] = bufsz;
393 err_args.args[2] = 0;
395 save_args = rtas.args;
396 rtas.args = err_args;
398 enter_rtas(__pa(&rtas.args));
400 err_args = rtas.args;
401 rtas.args = save_args;
403 /* Log the error in the unlikely case that there was one. */
404 if (unlikely(err_args.args[2] == 0)) {
405 if (altbuf) {
406 buf = altbuf;
407 } else {
408 buf = rtas_err_buf;
409 if (mem_init_done)
410 buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
412 if (buf)
413 memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
416 return buf;
419 #define get_errorlog_buffer() kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
421 #else /* CONFIG_RTAS_ERROR_LOGGING */
422 #define __fetch_rtas_last_error(x) NULL
423 #define get_errorlog_buffer() NULL
424 #endif
426 int rtas_call(int token, int nargs, int nret, int *outputs, ...)
428 va_list list;
429 int i;
430 unsigned long s;
431 struct rtas_args *rtas_args;
432 char *buff_copy = NULL;
433 int ret;
435 if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
436 return -1;
438 s = lock_rtas();
439 rtas_args = &rtas.args;
441 rtas_args->token = token;
442 rtas_args->nargs = nargs;
443 rtas_args->nret = nret;
444 rtas_args->rets = (rtas_arg_t *)&(rtas_args->args[nargs]);
445 va_start(list, outputs);
446 for (i = 0; i < nargs; ++i)
447 rtas_args->args[i] = va_arg(list, rtas_arg_t);
448 va_end(list);
450 for (i = 0; i < nret; ++i)
451 rtas_args->rets[i] = 0;
453 enter_rtas(__pa(rtas_args));
455 /* A -1 return code indicates that the last command couldn't
456 be completed due to a hardware error. */
457 if (rtas_args->rets[0] == -1)
458 buff_copy = __fetch_rtas_last_error(NULL);
460 if (nret > 1 && outputs != NULL)
461 for (i = 0; i < nret-1; ++i)
462 outputs[i] = rtas_args->rets[i+1];
463 ret = (nret > 0)? rtas_args->rets[0]: 0;
465 unlock_rtas(s);
467 if (buff_copy) {
468 log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
469 if (mem_init_done)
470 kfree(buff_copy);
472 return ret;
474 EXPORT_SYMBOL(rtas_call);
476 /* For RTAS_BUSY (-2), delay for 1 millisecond. For an extended busy status
477 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
479 unsigned int rtas_busy_delay_time(int status)
481 int order;
482 unsigned int ms = 0;
484 if (status == RTAS_BUSY) {
485 ms = 1;
486 } else if (status >= 9900 && status <= 9905) {
487 order = status - 9900;
488 for (ms = 1; order > 0; order--)
489 ms *= 10;
492 return ms;
494 EXPORT_SYMBOL(rtas_busy_delay_time);
496 /* For an RTAS busy status code, perform the hinted delay. */
497 unsigned int rtas_busy_delay(int status)
499 unsigned int ms;
501 might_sleep();
502 ms = rtas_busy_delay_time(status);
503 if (ms)
504 msleep(ms);
506 return ms;
508 EXPORT_SYMBOL(rtas_busy_delay);
510 static int rtas_error_rc(int rtas_rc)
512 int rc;
514 switch (rtas_rc) {
515 case -1: /* Hardware Error */
516 rc = -EIO;
517 break;
518 case -3: /* Bad indicator/domain/etc */
519 rc = -EINVAL;
520 break;
521 case -9000: /* Isolation error */
522 rc = -EFAULT;
523 break;
524 case -9001: /* Outstanding TCE/PTE */
525 rc = -EEXIST;
526 break;
527 case -9002: /* No usable slot */
528 rc = -ENODEV;
529 break;
530 default:
531 printk(KERN_ERR "%s: unexpected RTAS error %d\n",
532 __func__, rtas_rc);
533 rc = -ERANGE;
534 break;
536 return rc;
539 int rtas_get_power_level(int powerdomain, int *level)
541 int token = rtas_token("get-power-level");
542 int rc;
544 if (token == RTAS_UNKNOWN_SERVICE)
545 return -ENOENT;
547 while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
548 udelay(1);
550 if (rc < 0)
551 return rtas_error_rc(rc);
552 return rc;
554 EXPORT_SYMBOL(rtas_get_power_level);
556 int rtas_set_power_level(int powerdomain, int level, int *setlevel)
558 int token = rtas_token("set-power-level");
559 int rc;
561 if (token == RTAS_UNKNOWN_SERVICE)
562 return -ENOENT;
564 do {
565 rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
566 } while (rtas_busy_delay(rc));
568 if (rc < 0)
569 return rtas_error_rc(rc);
570 return rc;
572 EXPORT_SYMBOL(rtas_set_power_level);
574 int rtas_get_sensor(int sensor, int index, int *state)
576 int token = rtas_token("get-sensor-state");
577 int rc;
579 if (token == RTAS_UNKNOWN_SERVICE)
580 return -ENOENT;
582 do {
583 rc = rtas_call(token, 2, 2, state, sensor, index);
584 } while (rtas_busy_delay(rc));
586 if (rc < 0)
587 return rtas_error_rc(rc);
588 return rc;
590 EXPORT_SYMBOL(rtas_get_sensor);
592 bool rtas_indicator_present(int token, int *maxindex)
594 int proplen, count, i;
595 const struct indicator_elem {
596 u32 token;
597 u32 maxindex;
598 } *indicators;
600 indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
601 if (!indicators)
602 return false;
604 count = proplen / sizeof(struct indicator_elem);
606 for (i = 0; i < count; i++) {
607 if (indicators[i].token != token)
608 continue;
609 if (maxindex)
610 *maxindex = indicators[i].maxindex;
611 return true;
614 return false;
616 EXPORT_SYMBOL(rtas_indicator_present);
618 int rtas_set_indicator(int indicator, int index, int new_value)
620 int token = rtas_token("set-indicator");
621 int rc;
623 if (token == RTAS_UNKNOWN_SERVICE)
624 return -ENOENT;
626 do {
627 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
628 } while (rtas_busy_delay(rc));
630 if (rc < 0)
631 return rtas_error_rc(rc);
632 return rc;
634 EXPORT_SYMBOL(rtas_set_indicator);
637 * Ignoring RTAS extended delay
639 int rtas_set_indicator_fast(int indicator, int index, int new_value)
641 int rc;
642 int token = rtas_token("set-indicator");
644 if (token == RTAS_UNKNOWN_SERVICE)
645 return -ENOENT;
647 rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
649 WARN_ON(rc == -2 || (rc >= 9900 && rc <= 9905));
651 if (rc < 0)
652 return rtas_error_rc(rc);
654 return rc;
657 void rtas_restart(char *cmd)
659 if (rtas_flash_term_hook)
660 rtas_flash_term_hook(SYS_RESTART);
661 printk("RTAS system-reboot returned %d\n",
662 rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
663 for (;;);
666 void rtas_power_off(void)
668 if (rtas_flash_term_hook)
669 rtas_flash_term_hook(SYS_POWER_OFF);
670 /* allow power on only with power button press */
671 printk("RTAS power-off returned %d\n",
672 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
673 for (;;);
676 void rtas_halt(void)
678 if (rtas_flash_term_hook)
679 rtas_flash_term_hook(SYS_HALT);
680 /* allow power on only with power button press */
681 printk("RTAS power-off returned %d\n",
682 rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
683 for (;;);
686 /* Must be in the RMO region, so we place it here */
687 static char rtas_os_term_buf[2048];
689 void rtas_os_term(char *str)
691 int status;
693 if (panic_timeout)
694 return;
696 if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term"))
697 return;
699 snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
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));
706 if (status != 0)
707 printk(KERN_EMERG "ibm,os-term call failed %d\n",
708 status);
711 static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
712 #ifdef CONFIG_PPC_PSERIES
713 static void rtas_percpu_suspend_me(void *info)
715 long rc = H_SUCCESS;
716 unsigned long msr_save;
717 u16 slb_size = mmu_slb_size;
718 int cpu;
719 struct rtas_suspend_me_data *data =
720 (struct rtas_suspend_me_data *)info;
722 atomic_inc(&data->working);
724 /* really need to ensure MSR.EE is off for H_JOIN */
725 msr_save = mfmsr();
726 mtmsr(msr_save & ~(MSR_EE));
728 while (rc == H_SUCCESS && !atomic_read(&data->done))
729 rc = plpar_hcall_norets(H_JOIN);
731 mtmsr(msr_save);
733 if (rc == H_SUCCESS) {
734 /* This cpu was prodded and the suspend is complete. */
735 goto out;
736 } else if (rc == H_CONTINUE) {
737 /* All other cpus are in H_JOIN, this cpu does
738 * the suspend.
740 slb_set_size(SLB_MIN_SIZE);
741 printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n",
742 smp_processor_id());
743 data->error = rtas_call(data->token, 0, 1, NULL);
745 if (data->error) {
746 printk(KERN_DEBUG "ibm,suspend-me returned %d\n",
747 data->error);
748 slb_set_size(slb_size);
750 } else {
751 printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
752 smp_processor_id(), rc);
753 data->error = rc;
756 atomic_set(&data->done, 1);
758 /* This cpu did the suspend or got an error; in either case,
759 * we need to prod all other other cpus out of join state.
760 * Extra prods are harmless.
762 for_each_online_cpu(cpu)
763 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
764 out:
765 if (atomic_dec_return(&data->working) == 0)
766 complete(data->complete);
769 static int rtas_ibm_suspend_me(struct rtas_args *args)
771 long state;
772 long rc;
773 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
774 struct rtas_suspend_me_data data;
775 DECLARE_COMPLETION_ONSTACK(done);
777 if (!rtas_service_present("ibm,suspend-me"))
778 return -ENOSYS;
780 /* Make sure the state is valid */
781 rc = plpar_hcall(H_VASI_STATE, retbuf,
782 ((u64)args->args[0] << 32) | args->args[1]);
784 state = retbuf[0];
786 if (rc) {
787 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
788 return rc;
789 } else if (state == H_VASI_ENABLED) {
790 args->args[args->nargs] = RTAS_NOT_SUSPENDABLE;
791 return 0;
792 } else if (state != H_VASI_SUSPENDING) {
793 printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
794 state);
795 args->args[args->nargs] = -1;
796 return 0;
799 atomic_set(&data.working, 0);
800 atomic_set(&data.done, 0);
801 data.token = rtas_token("ibm,suspend-me");
802 data.error = 0;
803 data.complete = &done;
805 /* Call function on all CPUs. One of us will make the
806 * rtas call
808 if (on_each_cpu(rtas_percpu_suspend_me, &data, 0))
809 data.error = -EINVAL;
811 wait_for_completion(&done);
813 if (data.error != 0)
814 printk(KERN_ERR "Error doing global join\n");
816 return data.error;
818 #else /* CONFIG_PPC_PSERIES */
819 static int rtas_ibm_suspend_me(struct rtas_args *args)
821 return -ENOSYS;
823 #endif
825 asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
827 struct rtas_args args;
828 unsigned long flags;
829 char *buff_copy, *errbuf = NULL;
830 int nargs;
831 int rc;
833 if (!capable(CAP_SYS_ADMIN))
834 return -EPERM;
836 if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
837 return -EFAULT;
839 nargs = args.nargs;
840 if (nargs > ARRAY_SIZE(args.args)
841 || args.nret > ARRAY_SIZE(args.args)
842 || nargs + args.nret > ARRAY_SIZE(args.args))
843 return -EINVAL;
845 /* Copy in args. */
846 if (copy_from_user(args.args, uargs->args,
847 nargs * sizeof(rtas_arg_t)) != 0)
848 return -EFAULT;
850 if (args.token == RTAS_UNKNOWN_SERVICE)
851 return -EINVAL;
853 args.rets = &args.args[nargs];
854 memset(args.rets, 0, args.nret * sizeof(rtas_arg_t));
856 /* Need to handle ibm,suspend_me call specially */
857 if (args.token == ibm_suspend_me_token) {
858 rc = rtas_ibm_suspend_me(&args);
859 if (rc)
860 return rc;
861 goto copy_return;
864 buff_copy = get_errorlog_buffer();
866 flags = lock_rtas();
868 rtas.args = args;
869 enter_rtas(__pa(&rtas.args));
870 args = rtas.args;
872 /* A -1 return code indicates that the last command couldn't
873 be completed due to a hardware error. */
874 if (args.rets[0] == -1)
875 errbuf = __fetch_rtas_last_error(buff_copy);
877 unlock_rtas(flags);
879 if (buff_copy) {
880 if (errbuf)
881 log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
882 kfree(buff_copy);
885 copy_return:
886 /* Copy out args. */
887 if (copy_to_user(uargs->args + nargs,
888 args.args + nargs,
889 args.nret * sizeof(rtas_arg_t)) != 0)
890 return -EFAULT;
892 return 0;
896 * Call early during boot, before mem init or bootmem, to retrieve the RTAS
897 * informations from the device-tree and allocate the RMO buffer for userland
898 * accesses.
900 void __init rtas_initialize(void)
902 unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
904 /* Get RTAS dev node and fill up our "rtas" structure with infos
905 * about it.
907 rtas.dev = of_find_node_by_name(NULL, "rtas");
908 if (rtas.dev) {
909 const u32 *basep, *entryp, *sizep;
911 basep = of_get_property(rtas.dev, "linux,rtas-base", NULL);
912 sizep = of_get_property(rtas.dev, "rtas-size", NULL);
913 if (basep != NULL && sizep != NULL) {
914 rtas.base = *basep;
915 rtas.size = *sizep;
916 entryp = of_get_property(rtas.dev,
917 "linux,rtas-entry", NULL);
918 if (entryp == NULL) /* Ugh */
919 rtas.entry = rtas.base;
920 else
921 rtas.entry = *entryp;
922 } else
923 rtas.dev = NULL;
925 if (!rtas.dev)
926 return;
928 /* If RTAS was found, allocate the RMO buffer for it and look for
929 * the stop-self token if any
931 #ifdef CONFIG_PPC64
932 if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
933 rtas_region = min(lmb.rmo_size, RTAS_INSTANTIATE_MAX);
934 ibm_suspend_me_token = rtas_token("ibm,suspend-me");
936 #endif
937 rtas_rmo_buf = lmb_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
939 #ifdef CONFIG_RTAS_ERROR_LOGGING
940 rtas_last_error_token = rtas_token("rtas-last-error");
941 #endif
944 int __init early_init_dt_scan_rtas(unsigned long node,
945 const char *uname, int depth, void *data)
947 u32 *basep, *entryp, *sizep;
949 if (depth != 1 || strcmp(uname, "rtas") != 0)
950 return 0;
952 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
953 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
954 sizep = of_get_flat_dt_prop(node, "rtas-size", NULL);
956 if (basep && entryp && sizep) {
957 rtas.base = *basep;
958 rtas.entry = *entryp;
959 rtas.size = *sizep;
962 #ifdef CONFIG_UDBG_RTAS_CONSOLE
963 basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
964 if (basep)
965 rtas_putchar_token = *basep;
967 basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
968 if (basep)
969 rtas_getchar_token = *basep;
971 if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
972 rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
973 udbg_init_rtas_console();
975 #endif
977 /* break now */
978 return 1;
981 static raw_spinlock_t timebase_lock;
982 static u64 timebase = 0;
984 void __cpuinit rtas_give_timebase(void)
986 unsigned long flags;
988 local_irq_save(flags);
989 hard_irq_disable();
990 __raw_spin_lock(&timebase_lock);
991 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
992 timebase = get_tb();
993 __raw_spin_unlock(&timebase_lock);
995 while (timebase)
996 barrier();
997 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
998 local_irq_restore(flags);
1001 void __cpuinit rtas_take_timebase(void)
1003 while (!timebase)
1004 barrier();
1005 __raw_spin_lock(&timebase_lock);
1006 set_tb(timebase >> 32, timebase & 0xffffffff);
1007 timebase = 0;
1008 __raw_spin_unlock(&timebase_lock);