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v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *
   4 * Procedures for interfacing to the RTAS on CHRP machines.
   5 *
   6 * Peter Bergner, IBM	March 2001.
   7 * Copyright (C) 2001 IBM.
 
 
 
 
 
   8 */
   9
  10#include <stdarg.h>
  11#include <linux/kernel.h>
  12#include <linux/types.h>
  13#include <linux/spinlock.h>
  14#include <linux/export.h>
  15#include <linux/init.h>
  16#include <linux/capability.h>
  17#include <linux/delay.h>
  18#include <linux/cpu.h>
  19#include <linux/sched.h>
  20#include <linux/smp.h>
  21#include <linux/completion.h>
  22#include <linux/cpumask.h>
  23#include <linux/memblock.h>
  24#include <linux/slab.h>
  25#include <linux/reboot.h>
  26#include <linux/syscalls.h>
  27
  28#include <asm/interrupt.h>
  29#include <asm/prom.h>
  30#include <asm/rtas.h>
  31#include <asm/hvcall.h>
  32#include <asm/machdep.h>
  33#include <asm/firmware.h>
  34#include <asm/page.h>
  35#include <asm/param.h>
 
  36#include <asm/delay.h>
  37#include <linux/uaccess.h>
  38#include <asm/udbg.h>
  39#include <asm/syscalls.h>
  40#include <asm/smp.h>
  41#include <linux/atomic.h>
  42#include <asm/time.h>
  43#include <asm/mmu.h>
  44#include <asm/topology.h>
  45#include <asm/paca.h>
  46
  47/* This is here deliberately so it's only used in this file */
  48void enter_rtas(unsigned long);
  49
  50static inline void do_enter_rtas(unsigned long args)
  51{
  52	enter_rtas(args);
  53
  54	srr_regs_clobbered(); /* rtas uses SRRs, invalidate */
  55}
  56
  57struct rtas_t rtas = {
  58	.lock = __ARCH_SPIN_LOCK_UNLOCKED
  59};
  60EXPORT_SYMBOL(rtas);
  61
  62DEFINE_SPINLOCK(rtas_data_buf_lock);
  63EXPORT_SYMBOL(rtas_data_buf_lock);
  64
  65char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
  66EXPORT_SYMBOL(rtas_data_buf);
  67
  68unsigned long rtas_rmo_buf;
  69
  70/*
  71 * If non-NULL, this gets called when the kernel terminates.
  72 * This is done like this so rtas_flash can be a module.
  73 */
  74void (*rtas_flash_term_hook)(int);
  75EXPORT_SYMBOL(rtas_flash_term_hook);
  76
  77/* RTAS use home made raw locking instead of spin_lock_irqsave
  78 * because those can be called from within really nasty contexts
  79 * such as having the timebase stopped which would lockup with
  80 * normal locks and spinlock debugging enabled
  81 */
  82static unsigned long lock_rtas(void)
  83{
  84	unsigned long flags;
  85
  86	local_irq_save(flags);
  87	preempt_disable();
  88	arch_spin_lock(&rtas.lock);
  89	return flags;
  90}
  91
  92static void unlock_rtas(unsigned long flags)
  93{
  94	arch_spin_unlock(&rtas.lock);
  95	local_irq_restore(flags);
  96	preempt_enable();
  97}
  98
  99/*
 100 * call_rtas_display_status and call_rtas_display_status_delay
 101 * are designed only for very early low-level debugging, which
 102 * is why the token is hard-coded to 10.
 103 */
 104static void call_rtas_display_status(unsigned char c)
 105{
 
 106	unsigned long s;
 107
 108	if (!rtas.base)
 109		return;
 110
 111	s = lock_rtas();
 112	rtas_call_unlocked(&rtas.args, 10, 1, 1, NULL, c);
 
 
 
 
 
 
 
 
 113	unlock_rtas(s);
 114}
 115
 116static void call_rtas_display_status_delay(char c)
 117{
 118	static int pending_newline = 0;  /* did last write end with unprinted newline? */
 119	static int width = 16;
 120
 121	if (c == '\n') {	
 122		while (width-- > 0)
 123			call_rtas_display_status(' ');
 124		width = 16;
 125		mdelay(500);
 126		pending_newline = 1;
 127	} else {
 128		if (pending_newline) {
 129			call_rtas_display_status('\r');
 130			call_rtas_display_status('\n');
 131		} 
 132		pending_newline = 0;
 133		if (width--) {
 134			call_rtas_display_status(c);
 135			udelay(10000);
 136		}
 137	}
 138}
 139
 140void __init udbg_init_rtas_panel(void)
 141{
 142	udbg_putc = call_rtas_display_status_delay;
 143}
 144
 145#ifdef CONFIG_UDBG_RTAS_CONSOLE
 146
 147/* If you think you're dying before early_init_dt_scan_rtas() does its
 148 * work, you can hard code the token values for your firmware here and
 149 * hardcode rtas.base/entry etc.
 150 */
 151static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
 152static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
 153
 154static void udbg_rtascon_putc(char c)
 155{
 156	int tries;
 157
 158	if (!rtas.base)
 159		return;
 160
 161	/* Add CRs before LFs */
 162	if (c == '\n')
 163		udbg_rtascon_putc('\r');
 164
 165	/* if there is more than one character to be displayed, wait a bit */
 166	for (tries = 0; tries < 16; tries++) {
 167		if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
 168			break;
 169		udelay(1000);
 170	}
 171}
 172
 173static int udbg_rtascon_getc_poll(void)
 174{
 175	int c;
 176
 177	if (!rtas.base)
 178		return -1;
 179
 180	if (rtas_call(rtas_getchar_token, 0, 2, &c))
 181		return -1;
 182
 183	return c;
 184}
 185
 186static int udbg_rtascon_getc(void)
 187{
 188	int c;
 189
 190	while ((c = udbg_rtascon_getc_poll()) == -1)
 191		;
 192
 193	return c;
 194}
 195
 196
 197void __init udbg_init_rtas_console(void)
 198{
 199	udbg_putc = udbg_rtascon_putc;
 200	udbg_getc = udbg_rtascon_getc;
 201	udbg_getc_poll = udbg_rtascon_getc_poll;
 202}
 203#endif /* CONFIG_UDBG_RTAS_CONSOLE */
 204
 205void rtas_progress(char *s, unsigned short hex)
 206{
 207	struct device_node *root;
 208	int width;
 209	const __be32 *p;
 210	char *os;
 211	static int display_character, set_indicator;
 212	static int display_width, display_lines, form_feed;
 213	static const int *row_width;
 214	static DEFINE_SPINLOCK(progress_lock);
 215	static int current_line;
 216	static int pending_newline = 0;  /* did last write end with unprinted newline? */
 217
 218	if (!rtas.base)
 219		return;
 220
 221	if (display_width == 0) {
 222		display_width = 0x10;
 223		if ((root = of_find_node_by_path("/rtas"))) {
 224			if ((p = of_get_property(root,
 225					"ibm,display-line-length", NULL)))
 226				display_width = be32_to_cpu(*p);
 227			if ((p = of_get_property(root,
 228					"ibm,form-feed", NULL)))
 229				form_feed = be32_to_cpu(*p);
 230			if ((p = of_get_property(root,
 231					"ibm,display-number-of-lines", NULL)))
 232				display_lines = be32_to_cpu(*p);
 233			row_width = of_get_property(root,
 234					"ibm,display-truncation-length", NULL);
 235			of_node_put(root);
 236		}
 237		display_character = rtas_token("display-character");
 238		set_indicator = rtas_token("set-indicator");
 239	}
 240
 241	if (display_character == RTAS_UNKNOWN_SERVICE) {
 242		/* use hex display if available */
 243		if (set_indicator != RTAS_UNKNOWN_SERVICE)
 244			rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
 245		return;
 246	}
 247
 248	spin_lock(&progress_lock);
 249
 250	/*
 251	 * Last write ended with newline, but we didn't print it since
 252	 * it would just clear the bottom line of output. Print it now
 253	 * instead.
 254	 *
 255	 * If no newline is pending and form feed is supported, clear the
 256	 * display with a form feed; otherwise, print a CR to start output
 257	 * at the beginning of the line.
 258	 */
 259	if (pending_newline) {
 260		rtas_call(display_character, 1, 1, NULL, '\r');
 261		rtas_call(display_character, 1, 1, NULL, '\n');
 262		pending_newline = 0;
 263	} else {
 264		current_line = 0;
 265		if (form_feed)
 266			rtas_call(display_character, 1, 1, NULL,
 267				  (char)form_feed);
 268		else
 269			rtas_call(display_character, 1, 1, NULL, '\r');
 270	}
 271 
 272	if (row_width)
 273		width = row_width[current_line];
 274	else
 275		width = display_width;
 276	os = s;
 277	while (*os) {
 278		if (*os == '\n' || *os == '\r') {
 279			/* If newline is the last character, save it
 280			 * until next call to avoid bumping up the
 281			 * display output.
 282			 */
 283			if (*os == '\n' && !os[1]) {
 284				pending_newline = 1;
 285				current_line++;
 286				if (current_line > display_lines-1)
 287					current_line = display_lines-1;
 288				spin_unlock(&progress_lock);
 289				return;
 290			}
 291 
 292			/* RTAS wants CR-LF, not just LF */
 293 
 294			if (*os == '\n') {
 295				rtas_call(display_character, 1, 1, NULL, '\r');
 296				rtas_call(display_character, 1, 1, NULL, '\n');
 297			} else {
 298				/* CR might be used to re-draw a line, so we'll
 299				 * leave it alone and not add LF.
 300				 */
 301				rtas_call(display_character, 1, 1, NULL, *os);
 302			}
 303 
 304			if (row_width)
 305				width = row_width[current_line];
 306			else
 307				width = display_width;
 308		} else {
 309			width--;
 310			rtas_call(display_character, 1, 1, NULL, *os);
 311		}
 312 
 313		os++;
 314 
 315		/* if we overwrite the screen length */
 316		if (width <= 0)
 317			while ((*os != 0) && (*os != '\n') && (*os != '\r'))
 318				os++;
 319	}
 320 
 321	spin_unlock(&progress_lock);
 322}
 323EXPORT_SYMBOL(rtas_progress);		/* needed by rtas_flash module */
 324
 325int rtas_token(const char *service)
 326{
 327	const __be32 *tokp;
 328	if (rtas.dev == NULL)
 329		return RTAS_UNKNOWN_SERVICE;
 330	tokp = of_get_property(rtas.dev, service, NULL);
 331	return tokp ? be32_to_cpu(*tokp) : RTAS_UNKNOWN_SERVICE;
 332}
 333EXPORT_SYMBOL(rtas_token);
 334
 335int rtas_service_present(const char *service)
 336{
 337	return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
 338}
 339EXPORT_SYMBOL(rtas_service_present);
 340
 341#ifdef CONFIG_RTAS_ERROR_LOGGING
 342/*
 343 * Return the firmware-specified size of the error log buffer
 344 *  for all rtas calls that require an error buffer argument.
 345 *  This includes 'check-exception' and 'rtas-last-error'.
 346 */
 347int rtas_get_error_log_max(void)
 348{
 349	static int rtas_error_log_max;
 350	if (rtas_error_log_max)
 351		return rtas_error_log_max;
 352
 353	rtas_error_log_max = rtas_token ("rtas-error-log-max");
 354	if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
 355	    (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
 356		printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
 357			rtas_error_log_max);
 358		rtas_error_log_max = RTAS_ERROR_LOG_MAX;
 359	}
 360	return rtas_error_log_max;
 361}
 362EXPORT_SYMBOL(rtas_get_error_log_max);
 363
 364
 365static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
 366static int rtas_last_error_token;
 367
 368/** Return a copy of the detailed error text associated with the
 369 *  most recent failed call to rtas.  Because the error text
 370 *  might go stale if there are any other intervening rtas calls,
 371 *  this routine must be called atomically with whatever produced
 372 *  the error (i.e. with rtas.lock still held from the previous call).
 373 */
 374static char *__fetch_rtas_last_error(char *altbuf)
 375{
 376	struct rtas_args err_args, save_args;
 377	u32 bufsz;
 378	char *buf = NULL;
 379
 380	if (rtas_last_error_token == -1)
 381		return NULL;
 382
 383	bufsz = rtas_get_error_log_max();
 384
 385	err_args.token = cpu_to_be32(rtas_last_error_token);
 386	err_args.nargs = cpu_to_be32(2);
 387	err_args.nret = cpu_to_be32(1);
 388	err_args.args[0] = cpu_to_be32(__pa(rtas_err_buf));
 389	err_args.args[1] = cpu_to_be32(bufsz);
 390	err_args.args[2] = 0;
 391
 392	save_args = rtas.args;
 393	rtas.args = err_args;
 394
 395	do_enter_rtas(__pa(&rtas.args));
 396
 397	err_args = rtas.args;
 398	rtas.args = save_args;
 399
 400	/* Log the error in the unlikely case that there was one. */
 401	if (unlikely(err_args.args[2] == 0)) {
 402		if (altbuf) {
 403			buf = altbuf;
 404		} else {
 405			buf = rtas_err_buf;
 406			if (slab_is_available())
 407				buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
 408		}
 409		if (buf)
 410			memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
 411	}
 412
 413	return buf;
 414}
 415
 416#define get_errorlog_buffer()	kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
 417
 418#else /* CONFIG_RTAS_ERROR_LOGGING */
 419#define __fetch_rtas_last_error(x)	NULL
 420#define get_errorlog_buffer()		NULL
 421#endif
 422
 423
 424static void
 425va_rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret,
 426		      va_list list)
 427{
 428	int i;
 429
 430	args->token = cpu_to_be32(token);
 431	args->nargs = cpu_to_be32(nargs);
 432	args->nret  = cpu_to_be32(nret);
 433	args->rets  = &(args->args[nargs]);
 434
 435	for (i = 0; i < nargs; ++i)
 436		args->args[i] = cpu_to_be32(va_arg(list, __u32));
 437
 438	for (i = 0; i < nret; ++i)
 439		args->rets[i] = 0;
 440
 441	do_enter_rtas(__pa(args));
 442}
 443
 444void rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret, ...)
 445{
 446	va_list list;
 447
 448	va_start(list, nret);
 449	va_rtas_call_unlocked(args, token, nargs, nret, list);
 450	va_end(list);
 451}
 452
 453int rtas_call(int token, int nargs, int nret, int *outputs, ...)
 454{
 455	va_list list;
 456	int i;
 457	unsigned long s;
 458	struct rtas_args *rtas_args;
 459	char *buff_copy = NULL;
 460	int ret;
 461
 462	if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
 463		return -1;
 464
 465	s = lock_rtas();
 466
 467	/* We use the global rtas args buffer */
 468	rtas_args = &rtas.args;
 469
 
 
 
 
 470	va_start(list, outputs);
 471	va_rtas_call_unlocked(rtas_args, token, nargs, nret, list);
 
 472	va_end(list);
 473
 
 
 
 
 
 474	/* A -1 return code indicates that the last command couldn't
 475	   be completed due to a hardware error. */
 476	if (be32_to_cpu(rtas_args->rets[0]) == -1)
 477		buff_copy = __fetch_rtas_last_error(NULL);
 478
 479	if (nret > 1 && outputs != NULL)
 480		for (i = 0; i < nret-1; ++i)
 481			outputs[i] = be32_to_cpu(rtas_args->rets[i+1]);
 482	ret = (nret > 0)? be32_to_cpu(rtas_args->rets[0]): 0;
 483
 484	unlock_rtas(s);
 485
 486	if (buff_copy) {
 487		log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
 488		if (slab_is_available())
 489			kfree(buff_copy);
 490	}
 491	return ret;
 492}
 493EXPORT_SYMBOL(rtas_call);
 494
 495/* For RTAS_BUSY (-2), delay for 1 millisecond.  For an extended busy status
 496 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
 497 */
 498unsigned int rtas_busy_delay_time(int status)
 499{
 500	int order;
 501	unsigned int ms = 0;
 502
 503	if (status == RTAS_BUSY) {
 504		ms = 1;
 505	} else if (status >= RTAS_EXTENDED_DELAY_MIN &&
 506		   status <= RTAS_EXTENDED_DELAY_MAX) {
 507		order = status - RTAS_EXTENDED_DELAY_MIN;
 508		for (ms = 1; order > 0; order--)
 509			ms *= 10;
 510	}
 511
 512	return ms;
 513}
 514EXPORT_SYMBOL(rtas_busy_delay_time);
 515
 516/* For an RTAS busy status code, perform the hinted delay. */
 517unsigned int rtas_busy_delay(int status)
 518{
 519	unsigned int ms;
 520
 521	might_sleep();
 522	ms = rtas_busy_delay_time(status);
 523	if (ms && need_resched())
 524		msleep(ms);
 525
 526	return ms;
 527}
 528EXPORT_SYMBOL(rtas_busy_delay);
 529
 530static int rtas_error_rc(int rtas_rc)
 531{
 532	int rc;
 533
 534	switch (rtas_rc) {
 535		case -1: 		/* Hardware Error */
 536			rc = -EIO;
 537			break;
 538		case -3:		/* Bad indicator/domain/etc */
 539			rc = -EINVAL;
 540			break;
 541		case -9000:		/* Isolation error */
 542			rc = -EFAULT;
 543			break;
 544		case -9001:		/* Outstanding TCE/PTE */
 545			rc = -EEXIST;
 546			break;
 547		case -9002:		/* No usable slot */
 548			rc = -ENODEV;
 549			break;
 550		default:
 551			printk(KERN_ERR "%s: unexpected RTAS error %d\n",
 552					__func__, rtas_rc);
 553			rc = -ERANGE;
 554			break;
 555	}
 556	return rc;
 557}
 558
 559int rtas_get_power_level(int powerdomain, int *level)
 560{
 561	int token = rtas_token("get-power-level");
 562	int rc;
 563
 564	if (token == RTAS_UNKNOWN_SERVICE)
 565		return -ENOENT;
 566
 567	while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
 568		udelay(1);
 569
 570	if (rc < 0)
 571		return rtas_error_rc(rc);
 572	return rc;
 573}
 574EXPORT_SYMBOL(rtas_get_power_level);
 575
 576int rtas_set_power_level(int powerdomain, int level, int *setlevel)
 577{
 578	int token = rtas_token("set-power-level");
 579	int rc;
 580
 581	if (token == RTAS_UNKNOWN_SERVICE)
 582		return -ENOENT;
 583
 584	do {
 585		rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
 586	} while (rtas_busy_delay(rc));
 587
 588	if (rc < 0)
 589		return rtas_error_rc(rc);
 590	return rc;
 591}
 592EXPORT_SYMBOL(rtas_set_power_level);
 593
 594int rtas_get_sensor(int sensor, int index, int *state)
 595{
 596	int token = rtas_token("get-sensor-state");
 597	int rc;
 598
 599	if (token == RTAS_UNKNOWN_SERVICE)
 600		return -ENOENT;
 601
 602	do {
 603		rc = rtas_call(token, 2, 2, state, sensor, index);
 604	} while (rtas_busy_delay(rc));
 605
 606	if (rc < 0)
 607		return rtas_error_rc(rc);
 608	return rc;
 609}
 610EXPORT_SYMBOL(rtas_get_sensor);
 611
 612int rtas_get_sensor_fast(int sensor, int index, int *state)
 613{
 614	int token = rtas_token("get-sensor-state");
 615	int rc;
 616
 617	if (token == RTAS_UNKNOWN_SERVICE)
 618		return -ENOENT;
 619
 620	rc = rtas_call(token, 2, 2, state, sensor, index);
 621	WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
 622				    rc <= RTAS_EXTENDED_DELAY_MAX));
 623
 624	if (rc < 0)
 625		return rtas_error_rc(rc);
 626	return rc;
 627}
 628
 629bool rtas_indicator_present(int token, int *maxindex)
 630{
 631	int proplen, count, i;
 632	const struct indicator_elem {
 633		__be32 token;
 634		__be32 maxindex;
 635	} *indicators;
 636
 637	indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
 638	if (!indicators)
 639		return false;
 640
 641	count = proplen / sizeof(struct indicator_elem);
 642
 643	for (i = 0; i < count; i++) {
 644		if (__be32_to_cpu(indicators[i].token) != token)
 645			continue;
 646		if (maxindex)
 647			*maxindex = __be32_to_cpu(indicators[i].maxindex);
 648		return true;
 649	}
 650
 651	return false;
 652}
 653EXPORT_SYMBOL(rtas_indicator_present);
 654
 655int rtas_set_indicator(int indicator, int index, int new_value)
 656{
 657	int token = rtas_token("set-indicator");
 658	int rc;
 659
 660	if (token == RTAS_UNKNOWN_SERVICE)
 661		return -ENOENT;
 662
 663	do {
 664		rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
 665	} while (rtas_busy_delay(rc));
 666
 667	if (rc < 0)
 668		return rtas_error_rc(rc);
 669	return rc;
 670}
 671EXPORT_SYMBOL(rtas_set_indicator);
 672
 673/*
 674 * Ignoring RTAS extended delay
 675 */
 676int rtas_set_indicator_fast(int indicator, int index, int new_value)
 677{
 678	int rc;
 679	int token = rtas_token("set-indicator");
 680
 681	if (token == RTAS_UNKNOWN_SERVICE)
 682		return -ENOENT;
 683
 684	rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
 685
 686	WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
 687				    rc <= RTAS_EXTENDED_DELAY_MAX));
 688
 689	if (rc < 0)
 690		return rtas_error_rc(rc);
 691
 692	return rc;
 693}
 694
 695/**
 696 * rtas_ibm_suspend_me() - Call ibm,suspend-me to suspend the LPAR.
 697 *
 698 * @fw_status: RTAS call status will be placed here if not NULL.
 699 *
 700 * rtas_ibm_suspend_me() should be called only on a CPU which has
 701 * received H_CONTINUE from the H_JOIN hcall. All other active CPUs
 702 * should be waiting to return from H_JOIN.
 703 *
 704 * rtas_ibm_suspend_me() may suspend execution of the OS
 705 * indefinitely. Callers should take appropriate measures upon return, such as
 706 * resetting watchdog facilities.
 707 *
 708 * Callers may choose to retry this call if @fw_status is
 709 * %RTAS_THREADS_ACTIVE.
 710 *
 711 * Return:
 712 * 0          - The partition has resumed from suspend, possibly after
 713 *              migration to a different host.
 714 * -ECANCELED - The operation was aborted.
 715 * -EAGAIN    - There were other CPUs not in H_JOIN at the time of the call.
 716 * -EBUSY     - Some other condition prevented the suspend from succeeding.
 717 * -EIO       - Hardware/platform error.
 718 */
 719int rtas_ibm_suspend_me(int *fw_status)
 720{
 721	int fwrc;
 722	int ret;
 723
 724	fwrc = rtas_call(rtas_token("ibm,suspend-me"), 0, 1, NULL);
 725
 726	switch (fwrc) {
 727	case 0:
 728		ret = 0;
 729		break;
 730	case RTAS_SUSPEND_ABORTED:
 731		ret = -ECANCELED;
 732		break;
 733	case RTAS_THREADS_ACTIVE:
 734		ret = -EAGAIN;
 735		break;
 736	case RTAS_NOT_SUSPENDABLE:
 737	case RTAS_OUTSTANDING_COPROC:
 738		ret = -EBUSY;
 739		break;
 740	case -1:
 741	default:
 742		ret = -EIO;
 743		break;
 744	}
 745
 746	if (fw_status)
 747		*fw_status = fwrc;
 748
 749	return ret;
 750}
 751
 752void __noreturn rtas_restart(char *cmd)
 753{
 754	if (rtas_flash_term_hook)
 755		rtas_flash_term_hook(SYS_RESTART);
 756	printk("RTAS system-reboot returned %d\n",
 757	       rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
 758	for (;;);
 759}
 760
 761void rtas_power_off(void)
 762{
 763	if (rtas_flash_term_hook)
 764		rtas_flash_term_hook(SYS_POWER_OFF);
 765	/* allow power on only with power button press */
 766	printk("RTAS power-off returned %d\n",
 767	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
 768	for (;;);
 769}
 770
 771void __noreturn rtas_halt(void)
 772{
 773	if (rtas_flash_term_hook)
 774		rtas_flash_term_hook(SYS_HALT);
 775	/* allow power on only with power button press */
 776	printk("RTAS power-off returned %d\n",
 777	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
 778	for (;;);
 779}
 780
 781/* Must be in the RMO region, so we place it here */
 782static char rtas_os_term_buf[2048];
 783
 784void rtas_os_term(char *str)
 785{
 786	int status;
 787
 788	/*
 789	 * Firmware with the ibm,extended-os-term property is guaranteed
 790	 * to always return from an ibm,os-term call. Earlier versions without
 791	 * this property may terminate the partition which we want to avoid
 792	 * since it interferes with panic_timeout.
 793	 */
 794	if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
 795	    RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
 796		return;
 797
 798	snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
 799
 800	do {
 801		status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
 802				   __pa(rtas_os_term_buf));
 803	} while (rtas_busy_delay(status));
 804
 805	if (status != 0)
 806		printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
 807}
 808
 809/**
 810 * rtas_activate_firmware() - Activate a new version of firmware.
 811 *
 812 * Activate a new version of partition firmware. The OS must call this
 813 * after resuming from a partition hibernation or migration in order
 814 * to maintain the ability to perform live firmware updates. It's not
 815 * catastrophic for this method to be absent or to fail; just log the
 816 * condition in that case.
 817 *
 818 * Context: This function may sleep.
 819 */
 820void rtas_activate_firmware(void)
 821{
 822	int token;
 823	int fwrc;
 824
 825	token = rtas_token("ibm,activate-firmware");
 826	if (token == RTAS_UNKNOWN_SERVICE) {
 827		pr_notice("ibm,activate-firmware method unavailable\n");
 828		return;
 829	}
 830
 831	do {
 832		fwrc = rtas_call(token, 0, 1, NULL);
 833	} while (rtas_busy_delay(fwrc));
 834
 835	if (fwrc)
 836		pr_err("ibm,activate-firmware failed (%i)\n", fwrc);
 837}
 838
 839#ifdef CONFIG_PPC_PSERIES
 840/**
 841 * rtas_call_reentrant() - Used for reentrant rtas calls
 842 * @token:	Token for desired reentrant RTAS call
 843 * @nargs:	Number of Input Parameters
 844 * @nret:	Number of Output Parameters
 845 * @outputs:	Array of outputs
 846 * @...:	Inputs for desired RTAS call
 847 *
 848 * According to LoPAR documentation, only "ibm,int-on", "ibm,int-off",
 849 * "ibm,get-xive" and "ibm,set-xive" are currently reentrant.
 850 * Reentrant calls need their own rtas_args buffer, so not using rtas.args, but
 851 * PACA one instead.
 852 *
 853 * Return:	-1 on error,
 854 *		First output value of RTAS call if (nret > 0),
 855 *		0 otherwise,
 856 */
 857int rtas_call_reentrant(int token, int nargs, int nret, int *outputs, ...)
 858{
 859	va_list list;
 860	struct rtas_args *args;
 861	unsigned long flags;
 862	int i, ret = 0;
 863
 864	if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
 865		return -1;
 866
 867	local_irq_save(flags);
 868	preempt_disable();
 
 
 
 
 
 
 869
 870	/* We use the per-cpu (PACA) rtas args buffer */
 871	args = local_paca->rtas_args_reentrant;
 872
 873	va_start(list, outputs);
 874	va_rtas_call_unlocked(args, token, nargs, nret, list);
 875	va_end(list);
 876
 877	if (nret > 1 && outputs)
 878		for (i = 0; i < nret - 1; ++i)
 879			outputs[i] = be32_to_cpu(args->rets[i + 1]);
 880
 881	if (nret > 0)
 882		ret = be32_to_cpu(args->rets[0]);
 
 883
 884	local_irq_restore(flags);
 885	preempt_enable();
 886
 887	return ret;
 888}
 889
 890#endif /* CONFIG_PPC_PSERIES */
 
 
 
 
 891
 892/**
 893 * Find a specific pseries error log in an RTAS extended event log.
 894 * @log: RTAS error/event log
 895 * @section_id: two character section identifier
 896 *
 897 * Returns a pointer to the specified errorlog or NULL if not found.
 898 */
 899struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
 900					      uint16_t section_id)
 901{
 902	struct rtas_ext_event_log_v6 *ext_log =
 903		(struct rtas_ext_event_log_v6 *)log->buffer;
 904	struct pseries_errorlog *sect;
 905	unsigned char *p, *log_end;
 906	uint32_t ext_log_length = rtas_error_extended_log_length(log);
 907	uint8_t log_format = rtas_ext_event_log_format(ext_log);
 908	uint32_t company_id = rtas_ext_event_company_id(ext_log);
 909
 910	/* Check that we understand the format */
 911	if (ext_log_length < sizeof(struct rtas_ext_event_log_v6) ||
 912	    log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
 913	    company_id != RTAS_V6EXT_COMPANY_ID_IBM)
 914		return NULL;
 915
 916	log_end = log->buffer + ext_log_length;
 917	p = ext_log->vendor_log;
 918
 919	while (p < log_end) {
 920		sect = (struct pseries_errorlog *)p;
 921		if (pseries_errorlog_id(sect) == section_id)
 922			return sect;
 923		p += pseries_errorlog_length(sect);
 924	}
 925
 926	return NULL;
 927}
 928
 929#ifdef CONFIG_PPC_RTAS_FILTER
 930
 931/*
 932 * The sys_rtas syscall, as originally designed, allows root to pass
 933 * arbitrary physical addresses to RTAS calls. A number of RTAS calls
 934 * can be abused to write to arbitrary memory and do other things that
 935 * are potentially harmful to system integrity, and thus should only
 936 * be used inside the kernel and not exposed to userspace.
 937 *
 938 * All known legitimate users of the sys_rtas syscall will only ever
 939 * pass addresses that fall within the RMO buffer, and use a known
 940 * subset of RTAS calls.
 941 *
 942 * Accordingly, we filter RTAS requests to check that the call is
 943 * permitted, and that provided pointers fall within the RMO buffer.
 944 * The rtas_filters list contains an entry for each permitted call,
 945 * with the indexes of the parameters which are expected to contain
 946 * addresses and sizes of buffers allocated inside the RMO buffer.
 947 */
 948struct rtas_filter {
 949	const char *name;
 950	int token;
 951	/* Indexes into the args buffer, -1 if not used */
 952	int buf_idx1;
 953	int size_idx1;
 954	int buf_idx2;
 955	int size_idx2;
 956
 957	int fixed_size;
 958};
 959
 960static struct rtas_filter rtas_filters[] __ro_after_init = {
 961	{ "ibm,activate-firmware", -1, -1, -1, -1, -1 },
 962	{ "ibm,configure-connector", -1, 0, -1, 1, -1, 4096 },	/* Special cased */
 963	{ "display-character", -1, -1, -1, -1, -1 },
 964	{ "ibm,display-message", -1, 0, -1, -1, -1 },
 965	{ "ibm,errinjct", -1, 2, -1, -1, -1, 1024 },
 966	{ "ibm,close-errinjct", -1, -1, -1, -1, -1 },
 967	{ "ibm,open-errinjct", -1, -1, -1, -1, -1 },
 968	{ "ibm,get-config-addr-info2", -1, -1, -1, -1, -1 },
 969	{ "ibm,get-dynamic-sensor-state", -1, 1, -1, -1, -1 },
 970	{ "ibm,get-indices", -1, 2, 3, -1, -1 },
 971	{ "get-power-level", -1, -1, -1, -1, -1 },
 972	{ "get-sensor-state", -1, -1, -1, -1, -1 },
 973	{ "ibm,get-system-parameter", -1, 1, 2, -1, -1 },
 974	{ "get-time-of-day", -1, -1, -1, -1, -1 },
 975	{ "ibm,get-vpd", -1, 0, -1, 1, 2 },
 976	{ "ibm,lpar-perftools", -1, 2, 3, -1, -1 },
 977	{ "ibm,platform-dump", -1, 4, 5, -1, -1 },
 978	{ "ibm,read-slot-reset-state", -1, -1, -1, -1, -1 },
 979	{ "ibm,scan-log-dump", -1, 0, 1, -1, -1 },
 980	{ "ibm,set-dynamic-indicator", -1, 2, -1, -1, -1 },
 981	{ "ibm,set-eeh-option", -1, -1, -1, -1, -1 },
 982	{ "set-indicator", -1, -1, -1, -1, -1 },
 983	{ "set-power-level", -1, -1, -1, -1, -1 },
 984	{ "set-time-for-power-on", -1, -1, -1, -1, -1 },
 985	{ "ibm,set-system-parameter", -1, 1, -1, -1, -1 },
 986	{ "set-time-of-day", -1, -1, -1, -1, -1 },
 987#ifdef CONFIG_CPU_BIG_ENDIAN
 988	{ "ibm,suspend-me", -1, -1, -1, -1, -1 },
 989	{ "ibm,update-nodes", -1, 0, -1, -1, -1, 4096 },
 990	{ "ibm,update-properties", -1, 0, -1, -1, -1, 4096 },
 991#endif
 992	{ "ibm,physical-attestation", -1, 0, 1, -1, -1 },
 993};
 994
 995static bool in_rmo_buf(u32 base, u32 end)
 996{
 997	return base >= rtas_rmo_buf &&
 998		base < (rtas_rmo_buf + RTAS_USER_REGION_SIZE) &&
 999		base <= end &&
1000		end >= rtas_rmo_buf &&
1001		end < (rtas_rmo_buf + RTAS_USER_REGION_SIZE);
1002}
1003
1004static bool block_rtas_call(int token, int nargs,
1005			    struct rtas_args *args)
1006{
1007	int i;
1008
1009	for (i = 0; i < ARRAY_SIZE(rtas_filters); i++) {
1010		struct rtas_filter *f = &rtas_filters[i];
1011		u32 base, size, end;
1012
1013		if (token != f->token)
1014			continue;
1015
1016		if (f->buf_idx1 != -1) {
1017			base = be32_to_cpu(args->args[f->buf_idx1]);
1018			if (f->size_idx1 != -1)
1019				size = be32_to_cpu(args->args[f->size_idx1]);
1020			else if (f->fixed_size)
1021				size = f->fixed_size;
1022			else
1023				size = 1;
1024
1025			end = base + size - 1;
1026			if (!in_rmo_buf(base, end))
1027				goto err;
1028		}
 
 
 
1029
1030		if (f->buf_idx2 != -1) {
1031			base = be32_to_cpu(args->args[f->buf_idx2]);
1032			if (f->size_idx2 != -1)
1033				size = be32_to_cpu(args->args[f->size_idx2]);
1034			else if (f->fixed_size)
1035				size = f->fixed_size;
1036			else
1037				size = 1;
1038			end = base + size - 1;
1039
1040			/*
1041			 * Special case for ibm,configure-connector where the
1042			 * address can be 0
1043			 */
1044			if (!strcmp(f->name, "ibm,configure-connector") &&
1045			    base == 0)
1046				return false;
1047
1048			if (!in_rmo_buf(base, end))
1049				goto err;
1050		}
1051
1052		return false;
 
 
 
 
 
 
 
 
 
 
1053	}
1054
1055err:
1056	pr_err_ratelimited("sys_rtas: RTAS call blocked - exploit attempt?\n");
1057	pr_err_ratelimited("sys_rtas: token=0x%x, nargs=%d (called by %s)\n",
1058			   token, nargs, current->comm);
1059	return true;
1060}
1061
1062static void __init rtas_syscall_filter_init(void)
1063{
1064	unsigned int i;
 
 
1065
1066	for (i = 0; i < ARRAY_SIZE(rtas_filters); i++)
1067		rtas_filters[i].token = rtas_token(rtas_filters[i].name);
1068}
1069
1070#else
 
1071
1072static bool block_rtas_call(int token, int nargs,
1073			    struct rtas_args *args)
1074{
1075	return false;
1076}
1077
1078static void __init rtas_syscall_filter_init(void)
1079{
 
1080}
 
1081
1082#endif /* CONFIG_PPC_RTAS_FILTER */
1083
1084/* We assume to be passed big endian arguments */
1085SYSCALL_DEFINE1(rtas, struct rtas_args __user *, uargs)
1086{
1087	struct rtas_args args;
1088	unsigned long flags;
1089	char *buff_copy, *errbuf = NULL;
1090	int nargs, nret, token;
 
1091
1092	if (!capable(CAP_SYS_ADMIN))
1093		return -EPERM;
1094
1095	if (!rtas.entry)
1096		return -EINVAL;
1097
1098	if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
1099		return -EFAULT;
1100
1101	nargs = be32_to_cpu(args.nargs);
1102	nret  = be32_to_cpu(args.nret);
1103	token = be32_to_cpu(args.token);
1104
1105	if (nargs >= ARRAY_SIZE(args.args)
1106	    || nret > ARRAY_SIZE(args.args)
1107	    || nargs + nret > ARRAY_SIZE(args.args))
1108		return -EINVAL;
1109
1110	/* Copy in args. */
1111	if (copy_from_user(args.args, uargs->args,
1112			   nargs * sizeof(rtas_arg_t)) != 0)
1113		return -EFAULT;
1114
1115	if (token == RTAS_UNKNOWN_SERVICE)
1116		return -EINVAL;
1117
1118	args.rets = &args.args[nargs];
1119	memset(args.rets, 0, nret * sizeof(rtas_arg_t));
1120
1121	if (block_rtas_call(token, nargs, &args))
1122		return -EINVAL;
1123
1124	/* Need to handle ibm,suspend_me call specially */
1125	if (token == rtas_token("ibm,suspend-me")) {
1126
1127		/*
1128		 * rtas_ibm_suspend_me assumes the streamid handle is in cpu
1129		 * endian, or at least the hcall within it requires it.
1130		 */
1131		int rc = 0;
1132		u64 handle = ((u64)be32_to_cpu(args.args[0]) << 32)
1133		              | be32_to_cpu(args.args[1]);
1134		rc = rtas_syscall_dispatch_ibm_suspend_me(handle);
1135		if (rc == -EAGAIN)
1136			args.rets[0] = cpu_to_be32(RTAS_NOT_SUSPENDABLE);
1137		else if (rc == -EIO)
1138			args.rets[0] = cpu_to_be32(-1);
1139		else if (rc)
1140			return rc;
1141		goto copy_return;
1142	}
1143
1144	buff_copy = get_errorlog_buffer();
1145
1146	flags = lock_rtas();
1147
1148	rtas.args = args;
1149	do_enter_rtas(__pa(&rtas.args));
1150	args = rtas.args;
1151
1152	/* A -1 return code indicates that the last command couldn't
1153	   be completed due to a hardware error. */
1154	if (be32_to_cpu(args.rets[0]) == -1)
1155		errbuf = __fetch_rtas_last_error(buff_copy);
1156
1157	unlock_rtas(flags);
1158
1159	if (buff_copy) {
1160		if (errbuf)
1161			log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
1162		kfree(buff_copy);
1163	}
1164
1165 copy_return:
1166	/* Copy out args. */
1167	if (copy_to_user(uargs->args + nargs,
1168			 args.args + nargs,
1169			 nret * sizeof(rtas_arg_t)) != 0)
1170		return -EFAULT;
1171
1172	return 0;
1173}
1174
1175/*
1176 * Call early during boot, before mem init, to retrieve the RTAS
1177 * information from the device-tree and allocate the RMO buffer for userland
1178 * accesses.
1179 */
1180void __init rtas_initialize(void)
1181{
1182	unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
1183	u32 base, size, entry;
1184	int no_base, no_size, no_entry;
1185
1186	/* Get RTAS dev node and fill up our "rtas" structure with infos
1187	 * about it.
1188	 */
1189	rtas.dev = of_find_node_by_name(NULL, "rtas");
1190	if (!rtas.dev)
1191		return;
1192
1193	no_base = of_property_read_u32(rtas.dev, "linux,rtas-base", &base);
1194	no_size = of_property_read_u32(rtas.dev, "rtas-size", &size);
1195	if (no_base || no_size) {
1196		of_node_put(rtas.dev);
1197		rtas.dev = NULL;
1198		return;
 
 
 
 
 
 
 
1199	}
1200
1201	rtas.base = base;
1202	rtas.size = size;
1203	no_entry = of_property_read_u32(rtas.dev, "linux,rtas-entry", &entry);
1204	rtas.entry = no_entry ? rtas.base : entry;
1205
1206	/* If RTAS was found, allocate the RMO buffer for it and look for
1207	 * the stop-self token if any
1208	 */
1209#ifdef CONFIG_PPC64
1210	if (firmware_has_feature(FW_FEATURE_LPAR))
1211		rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
 
 
1212#endif
1213	rtas_rmo_buf = memblock_phys_alloc_range(RTAS_USER_REGION_SIZE, PAGE_SIZE,
1214						 0, rtas_region);
1215	if (!rtas_rmo_buf)
1216		panic("ERROR: RTAS: Failed to allocate %lx bytes below %pa\n",
1217		      PAGE_SIZE, &rtas_region);
1218
1219#ifdef CONFIG_RTAS_ERROR_LOGGING
1220	rtas_last_error_token = rtas_token("rtas-last-error");
1221#endif
1222
1223	rtas_syscall_filter_init();
1224}
1225
1226int __init early_init_dt_scan_rtas(unsigned long node,
1227		const char *uname, int depth, void *data)
1228{
1229	const u32 *basep, *entryp, *sizep;
1230
1231	if (depth != 1 || strcmp(uname, "rtas") != 0)
1232		return 0;
1233
1234	basep  = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
1235	entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
1236	sizep  = of_get_flat_dt_prop(node, "rtas-size", NULL);
1237
1238	if (basep && entryp && sizep) {
1239		rtas.base = *basep;
1240		rtas.entry = *entryp;
1241		rtas.size = *sizep;
1242	}
1243
1244#ifdef CONFIG_UDBG_RTAS_CONSOLE
1245	basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1246	if (basep)
1247		rtas_putchar_token = *basep;
1248
1249	basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1250	if (basep)
1251		rtas_getchar_token = *basep;
1252
1253	if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1254	    rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1255		udbg_init_rtas_console();
1256
1257#endif
1258
1259	/* break now */
1260	return 1;
1261}
1262
1263static arch_spinlock_t timebase_lock;
1264static u64 timebase = 0;
1265
1266void rtas_give_timebase(void)
1267{
1268	unsigned long flags;
1269
1270	local_irq_save(flags);
1271	hard_irq_disable();
1272	arch_spin_lock(&timebase_lock);
1273	rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1274	timebase = get_tb();
1275	arch_spin_unlock(&timebase_lock);
1276
1277	while (timebase)
1278		barrier();
1279	rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1280	local_irq_restore(flags);
1281}
1282
1283void rtas_take_timebase(void)
1284{
1285	while (!timebase)
1286		barrier();
1287	arch_spin_lock(&timebase_lock);
1288	set_tb(timebase >> 32, timebase & 0xffffffff);
1289	timebase = 0;
1290	arch_spin_unlock(&timebase_lock);
1291}
v3.1
 
   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/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/memblock.h>
  26#include <linux/slab.h>
  27#include <linux/reboot.h>
 
  28
 
  29#include <asm/prom.h>
  30#include <asm/rtas.h>
  31#include <asm/hvcall.h>
  32#include <asm/machdep.h>
  33#include <asm/firmware.h>
  34#include <asm/page.h>
  35#include <asm/param.h>
  36#include <asm/system.h>
  37#include <asm/delay.h>
  38#include <asm/uaccess.h>
  39#include <asm/udbg.h>
  40#include <asm/syscalls.h>
  41#include <asm/smp.h>
  42#include <linux/atomic.h>
  43#include <asm/time.h>
  44#include <asm/mmu.h>
  45#include <asm/topology.h>
  46#include <asm/pSeries_reconfig.h>
 
 
 
 
 
 
 
 
 
 
  47
  48struct rtas_t rtas = {
  49	.lock = __ARCH_SPIN_LOCK_UNLOCKED
  50};
  51EXPORT_SYMBOL(rtas);
  52
  53DEFINE_SPINLOCK(rtas_data_buf_lock);
  54EXPORT_SYMBOL(rtas_data_buf_lock);
  55
  56char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
  57EXPORT_SYMBOL(rtas_data_buf);
  58
  59unsigned long rtas_rmo_buf;
  60
  61/*
  62 * If non-NULL, this gets called when the kernel terminates.
  63 * This is done like this so rtas_flash can be a module.
  64 */
  65void (*rtas_flash_term_hook)(int);
  66EXPORT_SYMBOL(rtas_flash_term_hook);
  67
  68/* RTAS use home made raw locking instead of spin_lock_irqsave
  69 * because those can be called from within really nasty contexts
  70 * such as having the timebase stopped which would lockup with
  71 * normal locks and spinlock debugging enabled
  72 */
  73static unsigned long lock_rtas(void)
  74{
  75	unsigned long flags;
  76
  77	local_irq_save(flags);
  78	preempt_disable();
  79	arch_spin_lock_flags(&rtas.lock, flags);
  80	return flags;
  81}
  82
  83static void unlock_rtas(unsigned long flags)
  84{
  85	arch_spin_unlock(&rtas.lock);
  86	local_irq_restore(flags);
  87	preempt_enable();
  88}
  89
  90/*
  91 * call_rtas_display_status and call_rtas_display_status_delay
  92 * are designed only for very early low-level debugging, which
  93 * is why the token is hard-coded to 10.
  94 */
  95static void call_rtas_display_status(char c)
  96{
  97	struct rtas_args *args = &rtas.args;
  98	unsigned long s;
  99
 100	if (!rtas.base)
 101		return;
 
 102	s = lock_rtas();
 103
 104	args->token = 10;
 105	args->nargs = 1;
 106	args->nret  = 1;
 107	args->rets  = (rtas_arg_t *)&(args->args[1]);
 108	args->args[0] = (unsigned char)c;
 109
 110	enter_rtas(__pa(args));
 111
 112	unlock_rtas(s);
 113}
 114
 115static void call_rtas_display_status_delay(char c)
 116{
 117	static int pending_newline = 0;  /* did last write end with unprinted newline? */
 118	static int width = 16;
 119
 120	if (c == '\n') {	
 121		while (width-- > 0)
 122			call_rtas_display_status(' ');
 123		width = 16;
 124		mdelay(500);
 125		pending_newline = 1;
 126	} else {
 127		if (pending_newline) {
 128			call_rtas_display_status('\r');
 129			call_rtas_display_status('\n');
 130		} 
 131		pending_newline = 0;
 132		if (width--) {
 133			call_rtas_display_status(c);
 134			udelay(10000);
 135		}
 136	}
 137}
 138
 139void __init udbg_init_rtas_panel(void)
 140{
 141	udbg_putc = call_rtas_display_status_delay;
 142}
 143
 144#ifdef CONFIG_UDBG_RTAS_CONSOLE
 145
 146/* If you think you're dying before early_init_dt_scan_rtas() does its
 147 * work, you can hard code the token values for your firmware here and
 148 * hardcode rtas.base/entry etc.
 149 */
 150static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
 151static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
 152
 153static void udbg_rtascon_putc(char c)
 154{
 155	int tries;
 156
 157	if (!rtas.base)
 158		return;
 159
 160	/* Add CRs before LFs */
 161	if (c == '\n')
 162		udbg_rtascon_putc('\r');
 163
 164	/* if there is more than one character to be displayed, wait a bit */
 165	for (tries = 0; tries < 16; tries++) {
 166		if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
 167			break;
 168		udelay(1000);
 169	}
 170}
 171
 172static int udbg_rtascon_getc_poll(void)
 173{
 174	int c;
 175
 176	if (!rtas.base)
 177		return -1;
 178
 179	if (rtas_call(rtas_getchar_token, 0, 2, &c))
 180		return -1;
 181
 182	return c;
 183}
 184
 185static int udbg_rtascon_getc(void)
 186{
 187	int c;
 188
 189	while ((c = udbg_rtascon_getc_poll()) == -1)
 190		;
 191
 192	return c;
 193}
 194
 195
 196void __init udbg_init_rtas_console(void)
 197{
 198	udbg_putc = udbg_rtascon_putc;
 199	udbg_getc = udbg_rtascon_getc;
 200	udbg_getc_poll = udbg_rtascon_getc_poll;
 201}
 202#endif /* CONFIG_UDBG_RTAS_CONSOLE */
 203
 204void rtas_progress(char *s, unsigned short hex)
 205{
 206	struct device_node *root;
 207	int width;
 208	const int *p;
 209	char *os;
 210	static int display_character, set_indicator;
 211	static int display_width, display_lines, form_feed;
 212	static const int *row_width;
 213	static DEFINE_SPINLOCK(progress_lock);
 214	static int current_line;
 215	static int pending_newline = 0;  /* did last write end with unprinted newline? */
 216
 217	if (!rtas.base)
 218		return;
 219
 220	if (display_width == 0) {
 221		display_width = 0x10;
 222		if ((root = of_find_node_by_path("/rtas"))) {
 223			if ((p = of_get_property(root,
 224					"ibm,display-line-length", NULL)))
 225				display_width = *p;
 226			if ((p = of_get_property(root,
 227					"ibm,form-feed", NULL)))
 228				form_feed = *p;
 229			if ((p = of_get_property(root,
 230					"ibm,display-number-of-lines", NULL)))
 231				display_lines = *p;
 232			row_width = of_get_property(root,
 233					"ibm,display-truncation-length", NULL);
 234			of_node_put(root);
 235		}
 236		display_character = rtas_token("display-character");
 237		set_indicator = rtas_token("set-indicator");
 238	}
 239
 240	if (display_character == RTAS_UNKNOWN_SERVICE) {
 241		/* use hex display if available */
 242		if (set_indicator != RTAS_UNKNOWN_SERVICE)
 243			rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
 244		return;
 245	}
 246
 247	spin_lock(&progress_lock);
 248
 249	/*
 250	 * Last write ended with newline, but we didn't print it since
 251	 * it would just clear the bottom line of output. Print it now
 252	 * instead.
 253	 *
 254	 * If no newline is pending and form feed is supported, clear the
 255	 * display with a form feed; otherwise, print a CR to start output
 256	 * at the beginning of the line.
 257	 */
 258	if (pending_newline) {
 259		rtas_call(display_character, 1, 1, NULL, '\r');
 260		rtas_call(display_character, 1, 1, NULL, '\n');
 261		pending_newline = 0;
 262	} else {
 263		current_line = 0;
 264		if (form_feed)
 265			rtas_call(display_character, 1, 1, NULL,
 266				  (char)form_feed);
 267		else
 268			rtas_call(display_character, 1, 1, NULL, '\r');
 269	}
 270 
 271	if (row_width)
 272		width = row_width[current_line];
 273	else
 274		width = display_width;
 275	os = s;
 276	while (*os) {
 277		if (*os == '\n' || *os == '\r') {
 278			/* If newline is the last character, save it
 279			 * until next call to avoid bumping up the
 280			 * display output.
 281			 */
 282			if (*os == '\n' && !os[1]) {
 283				pending_newline = 1;
 284				current_line++;
 285				if (current_line > display_lines-1)
 286					current_line = display_lines-1;
 287				spin_unlock(&progress_lock);
 288				return;
 289			}
 290 
 291			/* RTAS wants CR-LF, not just LF */
 292 
 293			if (*os == '\n') {
 294				rtas_call(display_character, 1, 1, NULL, '\r');
 295				rtas_call(display_character, 1, 1, NULL, '\n');
 296			} else {
 297				/* CR might be used to re-draw a line, so we'll
 298				 * leave it alone and not add LF.
 299				 */
 300				rtas_call(display_character, 1, 1, NULL, *os);
 301			}
 302 
 303			if (row_width)
 304				width = row_width[current_line];
 305			else
 306				width = display_width;
 307		} else {
 308			width--;
 309			rtas_call(display_character, 1, 1, NULL, *os);
 310		}
 311 
 312		os++;
 313 
 314		/* if we overwrite the screen length */
 315		if (width <= 0)
 316			while ((*os != 0) && (*os != '\n') && (*os != '\r'))
 317				os++;
 318	}
 319 
 320	spin_unlock(&progress_lock);
 321}
 322EXPORT_SYMBOL(rtas_progress);		/* needed by rtas_flash module */
 323
 324int rtas_token(const char *service)
 325{
 326	const int *tokp;
 327	if (rtas.dev == NULL)
 328		return RTAS_UNKNOWN_SERVICE;
 329	tokp = of_get_property(rtas.dev, service, NULL);
 330	return tokp ? *tokp : RTAS_UNKNOWN_SERVICE;
 331}
 332EXPORT_SYMBOL(rtas_token);
 333
 334int rtas_service_present(const char *service)
 335{
 336	return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
 337}
 338EXPORT_SYMBOL(rtas_service_present);
 339
 340#ifdef CONFIG_RTAS_ERROR_LOGGING
 341/*
 342 * Return the firmware-specified size of the error log buffer
 343 *  for all rtas calls that require an error buffer argument.
 344 *  This includes 'check-exception' and 'rtas-last-error'.
 345 */
 346int rtas_get_error_log_max(void)
 347{
 348	static int rtas_error_log_max;
 349	if (rtas_error_log_max)
 350		return rtas_error_log_max;
 351
 352	rtas_error_log_max = rtas_token ("rtas-error-log-max");
 353	if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
 354	    (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
 355		printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
 356			rtas_error_log_max);
 357		rtas_error_log_max = RTAS_ERROR_LOG_MAX;
 358	}
 359	return rtas_error_log_max;
 360}
 361EXPORT_SYMBOL(rtas_get_error_log_max);
 362
 363
 364static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
 365static int rtas_last_error_token;
 366
 367/** Return a copy of the detailed error text associated with the
 368 *  most recent failed call to rtas.  Because the error text
 369 *  might go stale if there are any other intervening rtas calls,
 370 *  this routine must be called atomically with whatever produced
 371 *  the error (i.e. with rtas.lock still held from the previous call).
 372 */
 373static char *__fetch_rtas_last_error(char *altbuf)
 374{
 375	struct rtas_args err_args, save_args;
 376	u32 bufsz;
 377	char *buf = NULL;
 378
 379	if (rtas_last_error_token == -1)
 380		return NULL;
 381
 382	bufsz = rtas_get_error_log_max();
 383
 384	err_args.token = rtas_last_error_token;
 385	err_args.nargs = 2;
 386	err_args.nret = 1;
 387	err_args.args[0] = (rtas_arg_t)__pa(rtas_err_buf);
 388	err_args.args[1] = bufsz;
 389	err_args.args[2] = 0;
 390
 391	save_args = rtas.args;
 392	rtas.args = err_args;
 393
 394	enter_rtas(__pa(&rtas.args));
 395
 396	err_args = rtas.args;
 397	rtas.args = save_args;
 398
 399	/* Log the error in the unlikely case that there was one. */
 400	if (unlikely(err_args.args[2] == 0)) {
 401		if (altbuf) {
 402			buf = altbuf;
 403		} else {
 404			buf = rtas_err_buf;
 405			if (mem_init_done)
 406				buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
 407		}
 408		if (buf)
 409			memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
 410	}
 411
 412	return buf;
 413}
 414
 415#define get_errorlog_buffer()	kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
 416
 417#else /* CONFIG_RTAS_ERROR_LOGGING */
 418#define __fetch_rtas_last_error(x)	NULL
 419#define get_errorlog_buffer()		NULL
 420#endif
 421
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 422int rtas_call(int token, int nargs, int nret, int *outputs, ...)
 423{
 424	va_list list;
 425	int i;
 426	unsigned long s;
 427	struct rtas_args *rtas_args;
 428	char *buff_copy = NULL;
 429	int ret;
 430
 431	if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
 432		return -1;
 433
 434	s = lock_rtas();
 
 
 435	rtas_args = &rtas.args;
 436
 437	rtas_args->token = token;
 438	rtas_args->nargs = nargs;
 439	rtas_args->nret  = nret;
 440	rtas_args->rets  = (rtas_arg_t *)&(rtas_args->args[nargs]);
 441	va_start(list, outputs);
 442	for (i = 0; i < nargs; ++i)
 443		rtas_args->args[i] = va_arg(list, rtas_arg_t);
 444	va_end(list);
 445
 446	for (i = 0; i < nret; ++i)
 447		rtas_args->rets[i] = 0;
 448
 449	enter_rtas(__pa(rtas_args));
 450
 451	/* A -1 return code indicates that the last command couldn't
 452	   be completed due to a hardware error. */
 453	if (rtas_args->rets[0] == -1)
 454		buff_copy = __fetch_rtas_last_error(NULL);
 455
 456	if (nret > 1 && outputs != NULL)
 457		for (i = 0; i < nret-1; ++i)
 458			outputs[i] = rtas_args->rets[i+1];
 459	ret = (nret > 0)? rtas_args->rets[0]: 0;
 460
 461	unlock_rtas(s);
 462
 463	if (buff_copy) {
 464		log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
 465		if (mem_init_done)
 466			kfree(buff_copy);
 467	}
 468	return ret;
 469}
 470EXPORT_SYMBOL(rtas_call);
 471
 472/* For RTAS_BUSY (-2), delay for 1 millisecond.  For an extended busy status
 473 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
 474 */
 475unsigned int rtas_busy_delay_time(int status)
 476{
 477	int order;
 478	unsigned int ms = 0;
 479
 480	if (status == RTAS_BUSY) {
 481		ms = 1;
 482	} else if (status >= 9900 && status <= 9905) {
 483		order = status - 9900;
 
 484		for (ms = 1; order > 0; order--)
 485			ms *= 10;
 486	}
 487
 488	return ms;
 489}
 490EXPORT_SYMBOL(rtas_busy_delay_time);
 491
 492/* For an RTAS busy status code, perform the hinted delay. */
 493unsigned 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}
 504EXPORT_SYMBOL(rtas_busy_delay);
 505
 506static 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
 535int 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}
 550EXPORT_SYMBOL(rtas_get_power_level);
 551
 552int 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}
 568EXPORT_SYMBOL(rtas_set_power_level);
 569
 570int 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}
 586EXPORT_SYMBOL(rtas_get_sensor);
 587
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 588bool rtas_indicator_present(int token, int *maxindex)
 589{
 590	int proplen, count, i;
 591	const struct indicator_elem {
 592		u32 token;
 593		u32 maxindex;
 594	} *indicators;
 595
 596	indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
 597	if (!indicators)
 598		return false;
 599
 600	count = proplen / sizeof(struct indicator_elem);
 601
 602	for (i = 0; i < count; i++) {
 603		if (indicators[i].token != token)
 604			continue;
 605		if (maxindex)
 606			*maxindex = indicators[i].maxindex;
 607		return true;
 608	}
 609
 610	return false;
 611}
 612EXPORT_SYMBOL(rtas_indicator_present);
 613
 614int rtas_set_indicator(int indicator, int index, int new_value)
 615{
 616	int token = rtas_token("set-indicator");
 617	int rc;
 618
 619	if (token == RTAS_UNKNOWN_SERVICE)
 620		return -ENOENT;
 621
 622	do {
 623		rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
 624	} while (rtas_busy_delay(rc));
 625
 626	if (rc < 0)
 627		return rtas_error_rc(rc);
 628	return rc;
 629}
 630EXPORT_SYMBOL(rtas_set_indicator);
 631
 632/*
 633 * Ignoring RTAS extended delay
 634 */
 635int rtas_set_indicator_fast(int indicator, int index, int new_value)
 636{
 637	int rc;
 638	int token = rtas_token("set-indicator");
 639
 640	if (token == RTAS_UNKNOWN_SERVICE)
 641		return -ENOENT;
 642
 643	rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
 644
 645	WARN_ON(rc == -2 || (rc >= 9900 && rc <= 9905));
 
 646
 647	if (rc < 0)
 648		return rtas_error_rc(rc);
 649
 650	return rc;
 651}
 652
 653void rtas_restart(char *cmd)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 654{
 655	if (rtas_flash_term_hook)
 656		rtas_flash_term_hook(SYS_RESTART);
 657	printk("RTAS system-reboot returned %d\n",
 658	       rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
 659	for (;;);
 660}
 661
 662void rtas_power_off(void)
 663{
 664	if (rtas_flash_term_hook)
 665		rtas_flash_term_hook(SYS_POWER_OFF);
 666	/* allow power on only with power button press */
 667	printk("RTAS power-off returned %d\n",
 668	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
 669	for (;;);
 670}
 671
 672void rtas_halt(void)
 673{
 674	if (rtas_flash_term_hook)
 675		rtas_flash_term_hook(SYS_HALT);
 676	/* allow power on only with power button press */
 677	printk("RTAS power-off returned %d\n",
 678	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
 679	for (;;);
 680}
 681
 682/* Must be in the RMO region, so we place it here */
 683static char rtas_os_term_buf[2048];
 684
 685void rtas_os_term(char *str)
 686{
 687	int status;
 688
 689	/*
 690	 * Firmware with the ibm,extended-os-term property is guaranteed
 691	 * to always return from an ibm,os-term call. Earlier versions without
 692	 * this property may terminate the partition which we want to avoid
 693	 * since it interferes with panic_timeout.
 694	 */
 695	if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
 696	    RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
 697		return;
 698
 699	snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
 700
 701	do {
 702		status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
 703				   __pa(rtas_os_term_buf));
 704	} while (rtas_busy_delay(status));
 705
 706	if (status != 0)
 707		printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
 708}
 709
 710static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 711#ifdef CONFIG_PPC_PSERIES
 712static int __rtas_suspend_last_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 713{
 714	u16 slb_size = mmu_slb_size;
 715	int rc = H_MULTI_THREADS_ACTIVE;
 716	int cpu;
 717
 718	slb_set_size(SLB_MIN_SIZE);
 719	stop_topology_update();
 720	printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n", smp_processor_id());
 721
 722	while (rc == H_MULTI_THREADS_ACTIVE && !atomic_read(&data->done) &&
 723	       !atomic_read(&data->error))
 724		rc = rtas_call(data->token, 0, 1, NULL);
 725
 726	if (rc || atomic_read(&data->error)) {
 727		printk(KERN_DEBUG "ibm,suspend-me returned %d\n", rc);
 728		slb_set_size(slb_size);
 729	}
 730
 731	if (atomic_read(&data->error))
 732		rc = atomic_read(&data->error);
 733
 734	atomic_set(&data->error, rc);
 735	start_topology_update();
 736	pSeries_coalesce_init();
 737
 738	if (wake_when_done) {
 739		atomic_set(&data->done, 1);
 
 740
 741		for_each_online_cpu(cpu)
 742			plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
 743	}
 744
 745	if (atomic_dec_return(&data->working) == 0)
 746		complete(data->complete);
 747
 748	return rc;
 749}
 750
 751int rtas_suspend_last_cpu(struct rtas_suspend_me_data *data)
 752{
 753	atomic_inc(&data->working);
 754	return __rtas_suspend_last_cpu(data, 0);
 755}
 756
 757static int __rtas_suspend_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
 
 
 
 
 
 
 
 
 758{
 759	long rc = H_SUCCESS;
 760	unsigned long msr_save;
 761	int cpu;
 
 
 
 
 
 
 
 
 
 
 762
 763	atomic_inc(&data->working);
 
 764
 765	/* really need to ensure MSR.EE is off for H_JOIN */
 766	msr_save = mfmsr();
 767	mtmsr(msr_save & ~(MSR_EE));
 
 
 
 768
 769	while (rc == H_SUCCESS && !atomic_read(&data->done) && !atomic_read(&data->error))
 770		rc = plpar_hcall_norets(H_JOIN);
 771
 772	mtmsr(msr_save);
 773
 774	if (rc == H_SUCCESS) {
 775		/* This cpu was prodded and the suspend is complete. */
 776		goto out;
 777	} else if (rc == H_CONTINUE) {
 778		/* All other cpus are in H_JOIN, this cpu does
 779		 * the suspend.
 780		 */
 781		return __rtas_suspend_last_cpu(data, wake_when_done);
 782	} else {
 783		printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
 784		       smp_processor_id(), rc);
 785		atomic_set(&data->error, rc);
 786	}
 
 
 
 
 
 
 
 
 
 
 
 
 787
 788	if (wake_when_done) {
 789		atomic_set(&data->done, 1);
 790
 791		/* This cpu did the suspend or got an error; in either case,
 792		 * we need to prod all other other cpus out of join state.
 793		 * Extra prods are harmless.
 794		 */
 795		for_each_online_cpu(cpu)
 796			plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
 797	}
 798out:
 799	if (atomic_dec_return(&data->working) == 0)
 800		complete(data->complete);
 801	return rc;
 802}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 803
 804int rtas_suspend_cpu(struct rtas_suspend_me_data *data)
 805{
 806	return __rtas_suspend_cpu(data, 0);
 
 
 
 
 807}
 808
 809static void rtas_percpu_suspend_me(void *info)
 
 810{
 811	__rtas_suspend_cpu((struct rtas_suspend_me_data *)info, 1);
 812}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 813
 814int rtas_ibm_suspend_me(struct rtas_args *args)
 815{
 816	long state;
 817	long rc;
 818	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
 819	struct rtas_suspend_me_data data;
 820	DECLARE_COMPLETION_ONSTACK(done);
 821
 822	if (!rtas_service_present("ibm,suspend-me"))
 823		return -ENOSYS;
 
 
 
 
 
 
 
 824
 825	/* Make sure the state is valid */
 826	rc = plpar_hcall(H_VASI_STATE, retbuf,
 827			 ((u64)args->args[0] << 32) | args->args[1]);
 
 
 
 
 828
 829	state = retbuf[0];
 
 
 830
 831	if (rc) {
 832		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
 833		return rc;
 834	} else if (state == H_VASI_ENABLED) {
 835		args->args[args->nargs] = RTAS_NOT_SUSPENDABLE;
 836		return 0;
 837	} else if (state != H_VASI_SUSPENDING) {
 838		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
 839		       state);
 840		args->args[args->nargs] = -1;
 841		return 0;
 842	}
 843
 844	atomic_set(&data.working, 0);
 845	atomic_set(&data.done, 0);
 846	atomic_set(&data.error, 0);
 847	data.token = rtas_token("ibm,suspend-me");
 848	data.complete = &done;
 
 849
 850	/* Call function on all CPUs.  One of us will make the
 851	 * rtas call
 852	 */
 853	if (on_each_cpu(rtas_percpu_suspend_me, &data, 0))
 854		atomic_set(&data.error, -EINVAL);
 855
 856	wait_for_completion(&done);
 
 
 857
 858	if (atomic_read(&data.error) != 0)
 859		printk(KERN_ERR "Error doing global join\n");
 860
 861	return atomic_read(&data.error);
 
 
 
 862}
 863#else /* CONFIG_PPC_PSERIES */
 864int rtas_ibm_suspend_me(struct rtas_args *args)
 865{
 866	return -ENOSYS;
 867}
 868#endif
 869
 870asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
 
 
 
 871{
 872	struct rtas_args args;
 873	unsigned long flags;
 874	char *buff_copy, *errbuf = NULL;
 875	int nargs;
 876	int rc;
 877
 878	if (!capable(CAP_SYS_ADMIN))
 879		return -EPERM;
 880
 
 
 
 881	if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
 882		return -EFAULT;
 883
 884	nargs = args.nargs;
 885	if (nargs > ARRAY_SIZE(args.args)
 886	    || args.nret > ARRAY_SIZE(args.args)
 887	    || nargs + args.nret > ARRAY_SIZE(args.args))
 
 
 
 888		return -EINVAL;
 889
 890	/* Copy in args. */
 891	if (copy_from_user(args.args, uargs->args,
 892			   nargs * sizeof(rtas_arg_t)) != 0)
 893		return -EFAULT;
 894
 895	if (args.token == RTAS_UNKNOWN_SERVICE)
 896		return -EINVAL;
 897
 898	args.rets = &args.args[nargs];
 899	memset(args.rets, 0, args.nret * sizeof(rtas_arg_t));
 
 
 
 900
 901	/* Need to handle ibm,suspend_me call specially */
 902	if (args.token == ibm_suspend_me_token) {
 903		rc = rtas_ibm_suspend_me(&args);
 904		if (rc)
 
 
 
 
 
 
 
 
 
 
 
 
 905			return rc;
 906		goto copy_return;
 907	}
 908
 909	buff_copy = get_errorlog_buffer();
 910
 911	flags = lock_rtas();
 912
 913	rtas.args = args;
 914	enter_rtas(__pa(&rtas.args));
 915	args = rtas.args;
 916
 917	/* A -1 return code indicates that the last command couldn't
 918	   be completed due to a hardware error. */
 919	if (args.rets[0] == -1)
 920		errbuf = __fetch_rtas_last_error(buff_copy);
 921
 922	unlock_rtas(flags);
 923
 924	if (buff_copy) {
 925		if (errbuf)
 926			log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
 927		kfree(buff_copy);
 928	}
 929
 930 copy_return:
 931	/* Copy out args. */
 932	if (copy_to_user(uargs->args + nargs,
 933			 args.args + nargs,
 934			 args.nret * sizeof(rtas_arg_t)) != 0)
 935		return -EFAULT;
 936
 937	return 0;
 938}
 939
 940/*
 941 * Call early during boot, before mem init or bootmem, to retrieve the RTAS
 942 * informations from the device-tree and allocate the RMO buffer for userland
 943 * accesses.
 944 */
 945void __init rtas_initialize(void)
 946{
 947	unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
 
 
 948
 949	/* Get RTAS dev node and fill up our "rtas" structure with infos
 950	 * about it.
 951	 */
 952	rtas.dev = of_find_node_by_name(NULL, "rtas");
 953	if (rtas.dev) {
 954		const u32 *basep, *entryp, *sizep;
 955
 956		basep = of_get_property(rtas.dev, "linux,rtas-base", NULL);
 957		sizep = of_get_property(rtas.dev, "rtas-size", NULL);
 958		if (basep != NULL && sizep != NULL) {
 959			rtas.base = *basep;
 960			rtas.size = *sizep;
 961			entryp = of_get_property(rtas.dev,
 962					"linux,rtas-entry", NULL);
 963			if (entryp == NULL) /* Ugh */
 964				rtas.entry = rtas.base;
 965			else
 966				rtas.entry = *entryp;
 967		} else
 968			rtas.dev = NULL;
 969	}
 970	if (!rtas.dev)
 971		return;
 
 
 
 972
 973	/* If RTAS was found, allocate the RMO buffer for it and look for
 974	 * the stop-self token if any
 975	 */
 976#ifdef CONFIG_PPC64
 977	if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
 978		rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
 979		ibm_suspend_me_token = rtas_token("ibm,suspend-me");
 980	}
 981#endif
 982	rtas_rmo_buf = memblock_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
 
 
 
 
 983
 984#ifdef CONFIG_RTAS_ERROR_LOGGING
 985	rtas_last_error_token = rtas_token("rtas-last-error");
 986#endif
 
 
 987}
 988
 989int __init early_init_dt_scan_rtas(unsigned long node,
 990		const char *uname, int depth, void *data)
 991{
 992	u32 *basep, *entryp, *sizep;
 993
 994	if (depth != 1 || strcmp(uname, "rtas") != 0)
 995		return 0;
 996
 997	basep  = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
 998	entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
 999	sizep  = of_get_flat_dt_prop(node, "rtas-size", NULL);
1000
1001	if (basep && entryp && sizep) {
1002		rtas.base = *basep;
1003		rtas.entry = *entryp;
1004		rtas.size = *sizep;
1005	}
1006
1007#ifdef CONFIG_UDBG_RTAS_CONSOLE
1008	basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1009	if (basep)
1010		rtas_putchar_token = *basep;
1011
1012	basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1013	if (basep)
1014		rtas_getchar_token = *basep;
1015
1016	if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1017	    rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1018		udbg_init_rtas_console();
1019
1020#endif
1021
1022	/* break now */
1023	return 1;
1024}
1025
1026static arch_spinlock_t timebase_lock;
1027static u64 timebase = 0;
1028
1029void __cpuinit rtas_give_timebase(void)
1030{
1031	unsigned long flags;
1032
1033	local_irq_save(flags);
1034	hard_irq_disable();
1035	arch_spin_lock(&timebase_lock);
1036	rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1037	timebase = get_tb();
1038	arch_spin_unlock(&timebase_lock);
1039
1040	while (timebase)
1041		barrier();
1042	rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1043	local_irq_restore(flags);
1044}
1045
1046void __cpuinit rtas_take_timebase(void)
1047{
1048	while (!timebase)
1049		barrier();
1050	arch_spin_lock(&timebase_lock);
1051	set_tb(timebase >> 32, timebase & 0xffffffff);
1052	timebase = 0;
1053	arch_spin_unlock(&timebase_lock);
1054}