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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}
v4.10.11
 
   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 <linux/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/* This is here deliberately so it's only used in this file */
  48void enter_rtas(unsigned long);
  49
 
 
 
 
 
 
 
  50struct rtas_t rtas = {
  51	.lock = __ARCH_SPIN_LOCK_UNLOCKED
  52};
  53EXPORT_SYMBOL(rtas);
  54
  55DEFINE_SPINLOCK(rtas_data_buf_lock);
  56EXPORT_SYMBOL(rtas_data_buf_lock);
  57
  58char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
  59EXPORT_SYMBOL(rtas_data_buf);
  60
  61unsigned long rtas_rmo_buf;
  62
  63/*
  64 * If non-NULL, this gets called when the kernel terminates.
  65 * This is done like this so rtas_flash can be a module.
  66 */
  67void (*rtas_flash_term_hook)(int);
  68EXPORT_SYMBOL(rtas_flash_term_hook);
  69
  70/* RTAS use home made raw locking instead of spin_lock_irqsave
  71 * because those can be called from within really nasty contexts
  72 * such as having the timebase stopped which would lockup with
  73 * normal locks and spinlock debugging enabled
  74 */
  75static unsigned long lock_rtas(void)
  76{
  77	unsigned long flags;
  78
  79	local_irq_save(flags);
  80	preempt_disable();
  81	arch_spin_lock_flags(&rtas.lock, flags);
  82	return flags;
  83}
  84
  85static void unlock_rtas(unsigned long flags)
  86{
  87	arch_spin_unlock(&rtas.lock);
  88	local_irq_restore(flags);
  89	preempt_enable();
  90}
  91
  92/*
  93 * call_rtas_display_status and call_rtas_display_status_delay
  94 * are designed only for very early low-level debugging, which
  95 * is why the token is hard-coded to 10.
  96 */
  97static void call_rtas_display_status(unsigned char c)
  98{
  99	unsigned long s;
 100
 101	if (!rtas.base)
 102		return;
 103
 104	s = lock_rtas();
 105	rtas_call_unlocked(&rtas.args, 10, 1, 1, NULL, c);
 106	unlock_rtas(s);
 107}
 108
 109static void call_rtas_display_status_delay(char c)
 110{
 111	static int pending_newline = 0;  /* did last write end with unprinted newline? */
 112	static int width = 16;
 113
 114	if (c == '\n') {	
 115		while (width-- > 0)
 116			call_rtas_display_status(' ');
 117		width = 16;
 118		mdelay(500);
 119		pending_newline = 1;
 120	} else {
 121		if (pending_newline) {
 122			call_rtas_display_status('\r');
 123			call_rtas_display_status('\n');
 124		} 
 125		pending_newline = 0;
 126		if (width--) {
 127			call_rtas_display_status(c);
 128			udelay(10000);
 129		}
 130	}
 131}
 132
 133void __init udbg_init_rtas_panel(void)
 134{
 135	udbg_putc = call_rtas_display_status_delay;
 136}
 137
 138#ifdef CONFIG_UDBG_RTAS_CONSOLE
 139
 140/* If you think you're dying before early_init_dt_scan_rtas() does its
 141 * work, you can hard code the token values for your firmware here and
 142 * hardcode rtas.base/entry etc.
 143 */
 144static unsigned int rtas_putchar_token = RTAS_UNKNOWN_SERVICE;
 145static unsigned int rtas_getchar_token = RTAS_UNKNOWN_SERVICE;
 146
 147static void udbg_rtascon_putc(char c)
 148{
 149	int tries;
 150
 151	if (!rtas.base)
 152		return;
 153
 154	/* Add CRs before LFs */
 155	if (c == '\n')
 156		udbg_rtascon_putc('\r');
 157
 158	/* if there is more than one character to be displayed, wait a bit */
 159	for (tries = 0; tries < 16; tries++) {
 160		if (rtas_call(rtas_putchar_token, 1, 1, NULL, c) == 0)
 161			break;
 162		udelay(1000);
 163	}
 164}
 165
 166static int udbg_rtascon_getc_poll(void)
 167{
 168	int c;
 169
 170	if (!rtas.base)
 171		return -1;
 172
 173	if (rtas_call(rtas_getchar_token, 0, 2, &c))
 174		return -1;
 175
 176	return c;
 177}
 178
 179static int udbg_rtascon_getc(void)
 180{
 181	int c;
 182
 183	while ((c = udbg_rtascon_getc_poll()) == -1)
 184		;
 185
 186	return c;
 187}
 188
 189
 190void __init udbg_init_rtas_console(void)
 191{
 192	udbg_putc = udbg_rtascon_putc;
 193	udbg_getc = udbg_rtascon_getc;
 194	udbg_getc_poll = udbg_rtascon_getc_poll;
 195}
 196#endif /* CONFIG_UDBG_RTAS_CONSOLE */
 197
 198void rtas_progress(char *s, unsigned short hex)
 199{
 200	struct device_node *root;
 201	int width;
 202	const __be32 *p;
 203	char *os;
 204	static int display_character, set_indicator;
 205	static int display_width, display_lines, form_feed;
 206	static const int *row_width;
 207	static DEFINE_SPINLOCK(progress_lock);
 208	static int current_line;
 209	static int pending_newline = 0;  /* did last write end with unprinted newline? */
 210
 211	if (!rtas.base)
 212		return;
 213
 214	if (display_width == 0) {
 215		display_width = 0x10;
 216		if ((root = of_find_node_by_path("/rtas"))) {
 217			if ((p = of_get_property(root,
 218					"ibm,display-line-length", NULL)))
 219				display_width = be32_to_cpu(*p);
 220			if ((p = of_get_property(root,
 221					"ibm,form-feed", NULL)))
 222				form_feed = be32_to_cpu(*p);
 223			if ((p = of_get_property(root,
 224					"ibm,display-number-of-lines", NULL)))
 225				display_lines = be32_to_cpu(*p);
 226			row_width = of_get_property(root,
 227					"ibm,display-truncation-length", NULL);
 228			of_node_put(root);
 229		}
 230		display_character = rtas_token("display-character");
 231		set_indicator = rtas_token("set-indicator");
 232	}
 233
 234	if (display_character == RTAS_UNKNOWN_SERVICE) {
 235		/* use hex display if available */
 236		if (set_indicator != RTAS_UNKNOWN_SERVICE)
 237			rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
 238		return;
 239	}
 240
 241	spin_lock(&progress_lock);
 242
 243	/*
 244	 * Last write ended with newline, but we didn't print it since
 245	 * it would just clear the bottom line of output. Print it now
 246	 * instead.
 247	 *
 248	 * If no newline is pending and form feed is supported, clear the
 249	 * display with a form feed; otherwise, print a CR to start output
 250	 * at the beginning of the line.
 251	 */
 252	if (pending_newline) {
 253		rtas_call(display_character, 1, 1, NULL, '\r');
 254		rtas_call(display_character, 1, 1, NULL, '\n');
 255		pending_newline = 0;
 256	} else {
 257		current_line = 0;
 258		if (form_feed)
 259			rtas_call(display_character, 1, 1, NULL,
 260				  (char)form_feed);
 261		else
 262			rtas_call(display_character, 1, 1, NULL, '\r');
 263	}
 264 
 265	if (row_width)
 266		width = row_width[current_line];
 267	else
 268		width = display_width;
 269	os = s;
 270	while (*os) {
 271		if (*os == '\n' || *os == '\r') {
 272			/* If newline is the last character, save it
 273			 * until next call to avoid bumping up the
 274			 * display output.
 275			 */
 276			if (*os == '\n' && !os[1]) {
 277				pending_newline = 1;
 278				current_line++;
 279				if (current_line > display_lines-1)
 280					current_line = display_lines-1;
 281				spin_unlock(&progress_lock);
 282				return;
 283			}
 284 
 285			/* RTAS wants CR-LF, not just LF */
 286 
 287			if (*os == '\n') {
 288				rtas_call(display_character, 1, 1, NULL, '\r');
 289				rtas_call(display_character, 1, 1, NULL, '\n');
 290			} else {
 291				/* CR might be used to re-draw a line, so we'll
 292				 * leave it alone and not add LF.
 293				 */
 294				rtas_call(display_character, 1, 1, NULL, *os);
 295			}
 296 
 297			if (row_width)
 298				width = row_width[current_line];
 299			else
 300				width = display_width;
 301		} else {
 302			width--;
 303			rtas_call(display_character, 1, 1, NULL, *os);
 304		}
 305 
 306		os++;
 307 
 308		/* if we overwrite the screen length */
 309		if (width <= 0)
 310			while ((*os != 0) && (*os != '\n') && (*os != '\r'))
 311				os++;
 312	}
 313 
 314	spin_unlock(&progress_lock);
 315}
 316EXPORT_SYMBOL(rtas_progress);		/* needed by rtas_flash module */
 317
 318int rtas_token(const char *service)
 319{
 320	const __be32 *tokp;
 321	if (rtas.dev == NULL)
 322		return RTAS_UNKNOWN_SERVICE;
 323	tokp = of_get_property(rtas.dev, service, NULL);
 324	return tokp ? be32_to_cpu(*tokp) : RTAS_UNKNOWN_SERVICE;
 325}
 326EXPORT_SYMBOL(rtas_token);
 327
 328int rtas_service_present(const char *service)
 329{
 330	return rtas_token(service) != RTAS_UNKNOWN_SERVICE;
 331}
 332EXPORT_SYMBOL(rtas_service_present);
 333
 334#ifdef CONFIG_RTAS_ERROR_LOGGING
 335/*
 336 * Return the firmware-specified size of the error log buffer
 337 *  for all rtas calls that require an error buffer argument.
 338 *  This includes 'check-exception' and 'rtas-last-error'.
 339 */
 340int rtas_get_error_log_max(void)
 341{
 342	static int rtas_error_log_max;
 343	if (rtas_error_log_max)
 344		return rtas_error_log_max;
 345
 346	rtas_error_log_max = rtas_token ("rtas-error-log-max");
 347	if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
 348	    (rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
 349		printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
 350			rtas_error_log_max);
 351		rtas_error_log_max = RTAS_ERROR_LOG_MAX;
 352	}
 353	return rtas_error_log_max;
 354}
 355EXPORT_SYMBOL(rtas_get_error_log_max);
 356
 357
 358static char rtas_err_buf[RTAS_ERROR_LOG_MAX];
 359static int rtas_last_error_token;
 360
 361/** Return a copy of the detailed error text associated with the
 362 *  most recent failed call to rtas.  Because the error text
 363 *  might go stale if there are any other intervening rtas calls,
 364 *  this routine must be called atomically with whatever produced
 365 *  the error (i.e. with rtas.lock still held from the previous call).
 366 */
 367static char *__fetch_rtas_last_error(char *altbuf)
 368{
 369	struct rtas_args err_args, save_args;
 370	u32 bufsz;
 371	char *buf = NULL;
 372
 373	if (rtas_last_error_token == -1)
 374		return NULL;
 375
 376	bufsz = rtas_get_error_log_max();
 377
 378	err_args.token = cpu_to_be32(rtas_last_error_token);
 379	err_args.nargs = cpu_to_be32(2);
 380	err_args.nret = cpu_to_be32(1);
 381	err_args.args[0] = cpu_to_be32(__pa(rtas_err_buf));
 382	err_args.args[1] = cpu_to_be32(bufsz);
 383	err_args.args[2] = 0;
 384
 385	save_args = rtas.args;
 386	rtas.args = err_args;
 387
 388	enter_rtas(__pa(&rtas.args));
 389
 390	err_args = rtas.args;
 391	rtas.args = save_args;
 392
 393	/* Log the error in the unlikely case that there was one. */
 394	if (unlikely(err_args.args[2] == 0)) {
 395		if (altbuf) {
 396			buf = altbuf;
 397		} else {
 398			buf = rtas_err_buf;
 399			if (slab_is_available())
 400				buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
 401		}
 402		if (buf)
 403			memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
 404	}
 405
 406	return buf;
 407}
 408
 409#define get_errorlog_buffer()	kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
 410
 411#else /* CONFIG_RTAS_ERROR_LOGGING */
 412#define __fetch_rtas_last_error(x)	NULL
 413#define get_errorlog_buffer()		NULL
 414#endif
 415
 416
 417static void
 418va_rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret,
 419		      va_list list)
 420{
 421	int i;
 422
 423	args->token = cpu_to_be32(token);
 424	args->nargs = cpu_to_be32(nargs);
 425	args->nret  = cpu_to_be32(nret);
 426	args->rets  = &(args->args[nargs]);
 427
 428	for (i = 0; i < nargs; ++i)
 429		args->args[i] = cpu_to_be32(va_arg(list, __u32));
 430
 431	for (i = 0; i < nret; ++i)
 432		args->rets[i] = 0;
 433
 434	enter_rtas(__pa(args));
 435}
 436
 437void rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret, ...)
 438{
 439	va_list list;
 440
 441	va_start(list, nret);
 442	va_rtas_call_unlocked(args, token, nargs, nret, list);
 443	va_end(list);
 444}
 445
 446int rtas_call(int token, int nargs, int nret, int *outputs, ...)
 447{
 448	va_list list;
 449	int i;
 450	unsigned long s;
 451	struct rtas_args *rtas_args;
 452	char *buff_copy = NULL;
 453	int ret;
 454
 455	if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
 456		return -1;
 457
 458	s = lock_rtas();
 459
 460	/* We use the global rtas args buffer */
 461	rtas_args = &rtas.args;
 462
 463	va_start(list, outputs);
 464	va_rtas_call_unlocked(rtas_args, token, nargs, nret, list);
 465	va_end(list);
 466
 467	/* A -1 return code indicates that the last command couldn't
 468	   be completed due to a hardware error. */
 469	if (be32_to_cpu(rtas_args->rets[0]) == -1)
 470		buff_copy = __fetch_rtas_last_error(NULL);
 471
 472	if (nret > 1 && outputs != NULL)
 473		for (i = 0; i < nret-1; ++i)
 474			outputs[i] = be32_to_cpu(rtas_args->rets[i+1]);
 475	ret = (nret > 0)? be32_to_cpu(rtas_args->rets[0]): 0;
 476
 477	unlock_rtas(s);
 478
 479	if (buff_copy) {
 480		log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
 481		if (slab_is_available())
 482			kfree(buff_copy);
 483	}
 484	return ret;
 485}
 486EXPORT_SYMBOL(rtas_call);
 487
 488/* For RTAS_BUSY (-2), delay for 1 millisecond.  For an extended busy status
 489 * code of 990n, perform the hinted delay of 10^n (last digit) milliseconds.
 490 */
 491unsigned int rtas_busy_delay_time(int status)
 492{
 493	int order;
 494	unsigned int ms = 0;
 495
 496	if (status == RTAS_BUSY) {
 497		ms = 1;
 498	} else if (status >= RTAS_EXTENDED_DELAY_MIN &&
 499		   status <= RTAS_EXTENDED_DELAY_MAX) {
 500		order = status - RTAS_EXTENDED_DELAY_MIN;
 501		for (ms = 1; order > 0; order--)
 502			ms *= 10;
 503	}
 504
 505	return ms;
 506}
 507EXPORT_SYMBOL(rtas_busy_delay_time);
 508
 509/* For an RTAS busy status code, perform the hinted delay. */
 510unsigned int rtas_busy_delay(int status)
 511{
 512	unsigned int ms;
 513
 514	might_sleep();
 515	ms = rtas_busy_delay_time(status);
 516	if (ms && need_resched())
 517		msleep(ms);
 518
 519	return ms;
 520}
 521EXPORT_SYMBOL(rtas_busy_delay);
 522
 523static int rtas_error_rc(int rtas_rc)
 524{
 525	int rc;
 526
 527	switch (rtas_rc) {
 528		case -1: 		/* Hardware Error */
 529			rc = -EIO;
 530			break;
 531		case -3:		/* Bad indicator/domain/etc */
 532			rc = -EINVAL;
 533			break;
 534		case -9000:		/* Isolation error */
 535			rc = -EFAULT;
 536			break;
 537		case -9001:		/* Outstanding TCE/PTE */
 538			rc = -EEXIST;
 539			break;
 540		case -9002:		/* No usable slot */
 541			rc = -ENODEV;
 542			break;
 543		default:
 544			printk(KERN_ERR "%s: unexpected RTAS error %d\n",
 545					__func__, rtas_rc);
 546			rc = -ERANGE;
 547			break;
 548	}
 549	return rc;
 550}
 551
 552int rtas_get_power_level(int powerdomain, int *level)
 553{
 554	int token = rtas_token("get-power-level");
 555	int rc;
 556
 557	if (token == RTAS_UNKNOWN_SERVICE)
 558		return -ENOENT;
 559
 560	while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
 561		udelay(1);
 562
 563	if (rc < 0)
 564		return rtas_error_rc(rc);
 565	return rc;
 566}
 567EXPORT_SYMBOL(rtas_get_power_level);
 568
 569int rtas_set_power_level(int powerdomain, int level, int *setlevel)
 570{
 571	int token = rtas_token("set-power-level");
 572	int rc;
 573
 574	if (token == RTAS_UNKNOWN_SERVICE)
 575		return -ENOENT;
 576
 577	do {
 578		rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
 579	} while (rtas_busy_delay(rc));
 580
 581	if (rc < 0)
 582		return rtas_error_rc(rc);
 583	return rc;
 584}
 585EXPORT_SYMBOL(rtas_set_power_level);
 586
 587int rtas_get_sensor(int sensor, int index, int *state)
 588{
 589	int token = rtas_token("get-sensor-state");
 590	int rc;
 591
 592	if (token == RTAS_UNKNOWN_SERVICE)
 593		return -ENOENT;
 594
 595	do {
 596		rc = rtas_call(token, 2, 2, state, sensor, index);
 597	} while (rtas_busy_delay(rc));
 598
 599	if (rc < 0)
 600		return rtas_error_rc(rc);
 601	return rc;
 602}
 603EXPORT_SYMBOL(rtas_get_sensor);
 604
 605int rtas_get_sensor_fast(int sensor, int index, int *state)
 606{
 607	int token = rtas_token("get-sensor-state");
 608	int rc;
 609
 610	if (token == RTAS_UNKNOWN_SERVICE)
 611		return -ENOENT;
 612
 613	rc = rtas_call(token, 2, 2, state, sensor, index);
 614	WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
 615				    rc <= RTAS_EXTENDED_DELAY_MAX));
 616
 617	if (rc < 0)
 618		return rtas_error_rc(rc);
 619	return rc;
 620}
 621
 622bool rtas_indicator_present(int token, int *maxindex)
 623{
 624	int proplen, count, i;
 625	const struct indicator_elem {
 626		__be32 token;
 627		__be32 maxindex;
 628	} *indicators;
 629
 630	indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);
 631	if (!indicators)
 632		return false;
 633
 634	count = proplen / sizeof(struct indicator_elem);
 635
 636	for (i = 0; i < count; i++) {
 637		if (__be32_to_cpu(indicators[i].token) != token)
 638			continue;
 639		if (maxindex)
 640			*maxindex = __be32_to_cpu(indicators[i].maxindex);
 641		return true;
 642	}
 643
 644	return false;
 645}
 646EXPORT_SYMBOL(rtas_indicator_present);
 647
 648int rtas_set_indicator(int indicator, int index, int new_value)
 649{
 650	int token = rtas_token("set-indicator");
 651	int rc;
 652
 653	if (token == RTAS_UNKNOWN_SERVICE)
 654		return -ENOENT;
 655
 656	do {
 657		rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
 658	} while (rtas_busy_delay(rc));
 659
 660	if (rc < 0)
 661		return rtas_error_rc(rc);
 662	return rc;
 663}
 664EXPORT_SYMBOL(rtas_set_indicator);
 665
 666/*
 667 * Ignoring RTAS extended delay
 668 */
 669int rtas_set_indicator_fast(int indicator, int index, int new_value)
 670{
 671	int rc;
 672	int token = rtas_token("set-indicator");
 673
 674	if (token == RTAS_UNKNOWN_SERVICE)
 675		return -ENOENT;
 676
 677	rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
 678
 679	WARN_ON(rc == RTAS_BUSY || (rc >= RTAS_EXTENDED_DELAY_MIN &&
 680				    rc <= RTAS_EXTENDED_DELAY_MAX));
 681
 682	if (rc < 0)
 683		return rtas_error_rc(rc);
 684
 685	return rc;
 686}
 687
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 688void __noreturn rtas_restart(char *cmd)
 689{
 690	if (rtas_flash_term_hook)
 691		rtas_flash_term_hook(SYS_RESTART);
 692	printk("RTAS system-reboot returned %d\n",
 693	       rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
 694	for (;;);
 695}
 696
 697void rtas_power_off(void)
 698{
 699	if (rtas_flash_term_hook)
 700		rtas_flash_term_hook(SYS_POWER_OFF);
 701	/* allow power on only with power button press */
 702	printk("RTAS power-off returned %d\n",
 703	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
 704	for (;;);
 705}
 706
 707void __noreturn rtas_halt(void)
 708{
 709	if (rtas_flash_term_hook)
 710		rtas_flash_term_hook(SYS_HALT);
 711	/* allow power on only with power button press */
 712	printk("RTAS power-off returned %d\n",
 713	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
 714	for (;;);
 715}
 716
 717/* Must be in the RMO region, so we place it here */
 718static char rtas_os_term_buf[2048];
 719
 720void rtas_os_term(char *str)
 721{
 722	int status;
 723
 724	/*
 725	 * Firmware with the ibm,extended-os-term property is guaranteed
 726	 * to always return from an ibm,os-term call. Earlier versions without
 727	 * this property may terminate the partition which we want to avoid
 728	 * since it interferes with panic_timeout.
 729	 */
 730	if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
 731	    RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
 732		return;
 733
 734	snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
 735
 736	do {
 737		status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
 738				   __pa(rtas_os_term_buf));
 739	} while (rtas_busy_delay(status));
 740
 741	if (status != 0)
 742		printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
 743}
 744
 745static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
 746#ifdef CONFIG_PPC_PSERIES
 747static int __rtas_suspend_last_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
 
 
 
 
 
 
 
 
 
 748{
 749	u16 slb_size = mmu_slb_size;
 750	int rc = H_MULTI_THREADS_ACTIVE;
 751	int cpu;
 752
 753	slb_set_size(SLB_MIN_SIZE);
 754	printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n", smp_processor_id());
 755
 756	while (rc == H_MULTI_THREADS_ACTIVE && !atomic_read(&data->done) &&
 757	       !atomic_read(&data->error))
 758		rc = rtas_call(data->token, 0, 1, NULL);
 759
 760	if (rc || atomic_read(&data->error)) {
 761		printk(KERN_DEBUG "ibm,suspend-me returned %d\n", rc);
 762		slb_set_size(slb_size);
 763	}
 764
 765	if (atomic_read(&data->error))
 766		rc = atomic_read(&data->error);
 767
 768	atomic_set(&data->error, rc);
 769	pSeries_coalesce_init();
 770
 771	if (wake_when_done) {
 772		atomic_set(&data->done, 1);
 773
 774		for_each_online_cpu(cpu)
 775			plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
 776	}
 777
 778	if (atomic_dec_return(&data->working) == 0)
 779		complete(data->complete);
 
 780
 781	return rc;
 
 782}
 783
 784int rtas_suspend_last_cpu(struct rtas_suspend_me_data *data)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 785{
 786	atomic_inc(&data->working);
 787	return __rtas_suspend_last_cpu(data, 0);
 788}
 
 789
 790static int __rtas_suspend_cpu(struct rtas_suspend_me_data *data, int wake_when_done)
 791{
 792	long rc = H_SUCCESS;
 793	unsigned long msr_save;
 794	int cpu;
 795
 796	atomic_inc(&data->working);
 
 797
 798	/* really need to ensure MSR.EE is off for H_JOIN */
 799	msr_save = mfmsr();
 800	mtmsr(msr_save & ~(MSR_EE));
 801
 802	while (rc == H_SUCCESS && !atomic_read(&data->done) && !atomic_read(&data->error))
 803		rc = plpar_hcall_norets(H_JOIN);
 
 804
 805	mtmsr(msr_save);
 
 
 806
 807	if (rc == H_SUCCESS) {
 808		/* This cpu was prodded and the suspend is complete. */
 809		goto out;
 810	} else if (rc == H_CONTINUE) {
 811		/* All other cpus are in H_JOIN, this cpu does
 812		 * the suspend.
 813		 */
 814		return __rtas_suspend_last_cpu(data, wake_when_done);
 815	} else {
 816		printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
 817		       smp_processor_id(), rc);
 818		atomic_set(&data->error, rc);
 819	}
 820
 821	if (wake_when_done) {
 822		atomic_set(&data->done, 1);
 823
 824		/* This cpu did the suspend or got an error; in either case,
 825		 * we need to prod all other other cpus out of join state.
 826		 * Extra prods are harmless.
 827		 */
 828		for_each_online_cpu(cpu)
 829			plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
 830	}
 831out:
 832	if (atomic_dec_return(&data->working) == 0)
 833		complete(data->complete);
 834	return rc;
 835}
 836
 837int rtas_suspend_cpu(struct rtas_suspend_me_data *data)
 838{
 839	return __rtas_suspend_cpu(data, 0);
 840}
 841
 842static void rtas_percpu_suspend_me(void *info)
 843{
 844	__rtas_suspend_cpu((struct rtas_suspend_me_data *)info, 1);
 845}
 846
 847enum rtas_cpu_state {
 848	DOWN,
 849	UP,
 850};
 851
 852#ifndef CONFIG_SMP
 853static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
 854				cpumask_var_t cpus)
 855{
 856	if (!cpumask_empty(cpus)) {
 857		cpumask_clear(cpus);
 858		return -EINVAL;
 859	} else
 860		return 0;
 861}
 862#else
 863/* On return cpumask will be altered to indicate CPUs changed.
 864 * CPUs with states changed will be set in the mask,
 865 * CPUs with status unchanged will be unset in the mask. */
 866static int rtas_cpu_state_change_mask(enum rtas_cpu_state state,
 867				cpumask_var_t cpus)
 868{
 869	int cpu;
 870	int cpuret = 0;
 871	int ret = 0;
 872
 873	if (cpumask_empty(cpus))
 874		return 0;
 875
 876	for_each_cpu(cpu, cpus) {
 877		switch (state) {
 878		case DOWN:
 879			cpuret = cpu_down(cpu);
 880			break;
 881		case UP:
 882			cpuret = cpu_up(cpu);
 883			break;
 884		}
 885		if (cpuret) {
 886			pr_debug("%s: cpu_%s for cpu#%d returned %d.\n",
 887					__func__,
 888					((state == UP) ? "up" : "down"),
 889					cpu, cpuret);
 890			if (!ret)
 891				ret = cpuret;
 892			if (state == UP) {
 893				/* clear bits for unchanged cpus, return */
 894				cpumask_shift_right(cpus, cpus, cpu);
 895				cpumask_shift_left(cpus, cpus, cpu);
 896				break;
 897			} else {
 898				/* clear bit for unchanged cpu, continue */
 899				cpumask_clear_cpu(cpu, cpus);
 900			}
 901		}
 902	}
 903
 904	return ret;
 905}
 906#endif
 907
 908int rtas_online_cpus_mask(cpumask_var_t cpus)
 909{
 910	int ret;
 911
 912	ret = rtas_cpu_state_change_mask(UP, cpus);
 913
 914	if (ret) {
 915		cpumask_var_t tmp_mask;
 916
 917		if (!alloc_cpumask_var(&tmp_mask, GFP_TEMPORARY))
 918			return ret;
 919
 920		/* Use tmp_mask to preserve cpus mask from first failure */
 921		cpumask_copy(tmp_mask, cpus);
 922		rtas_offline_cpus_mask(tmp_mask);
 923		free_cpumask_var(tmp_mask);
 924	}
 925
 926	return ret;
 927}
 928EXPORT_SYMBOL(rtas_online_cpus_mask);
 929
 930int rtas_offline_cpus_mask(cpumask_var_t cpus)
 931{
 932	return rtas_cpu_state_change_mask(DOWN, cpus);
 933}
 934EXPORT_SYMBOL(rtas_offline_cpus_mask);
 935
 936int rtas_ibm_suspend_me(u64 handle)
 937{
 938	long state;
 939	long rc;
 940	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
 941	struct rtas_suspend_me_data data;
 942	DECLARE_COMPLETION_ONSTACK(done);
 943	cpumask_var_t offline_mask;
 944	int cpuret;
 945
 946	if (!rtas_service_present("ibm,suspend-me"))
 947		return -ENOSYS;
 948
 949	/* Make sure the state is valid */
 950	rc = plpar_hcall(H_VASI_STATE, retbuf, handle);
 951
 952	state = retbuf[0];
 953
 954	if (rc) {
 955		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
 956		return rc;
 957	} else if (state == H_VASI_ENABLED) {
 958		return -EAGAIN;
 959	} else if (state != H_VASI_SUSPENDING) {
 960		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
 961		       state);
 962		return -EIO;
 963	}
 964
 965	if (!alloc_cpumask_var(&offline_mask, GFP_TEMPORARY))
 966		return -ENOMEM;
 967
 968	atomic_set(&data.working, 0);
 969	atomic_set(&data.done, 0);
 970	atomic_set(&data.error, 0);
 971	data.token = rtas_token("ibm,suspend-me");
 972	data.complete = &done;
 973
 974	/* All present CPUs must be online */
 975	cpumask_andnot(offline_mask, cpu_present_mask, cpu_online_mask);
 976	cpuret = rtas_online_cpus_mask(offline_mask);
 977	if (cpuret) {
 978		pr_err("%s: Could not bring present CPUs online.\n", __func__);
 979		atomic_set(&data.error, cpuret);
 980		goto out;
 981	}
 982
 983	stop_topology_update();
 984
 985	/* Call function on all CPUs.  One of us will make the
 986	 * rtas call
 987	 */
 988	if (on_each_cpu(rtas_percpu_suspend_me, &data, 0))
 989		atomic_set(&data.error, -EINVAL);
 990
 991	wait_for_completion(&done);
 992
 993	if (atomic_read(&data.error) != 0)
 994		printk(KERN_ERR "Error doing global join\n");
 995
 996	start_topology_update();
 997
 998	/* Take down CPUs not online prior to suspend */
 999	cpuret = rtas_offline_cpus_mask(offline_mask);
1000	if (cpuret)
1001		pr_warn("%s: Could not restore CPUs to offline state.\n",
1002				__func__);
1003
1004out:
1005	free_cpumask_var(offline_mask);
1006	return atomic_read(&data.error);
1007}
1008#else /* CONFIG_PPC_PSERIES */
1009int rtas_ibm_suspend_me(u64 handle)
1010{
1011	return -ENOSYS;
1012}
1013#endif
1014
1015/**
1016 * Find a specific pseries error log in an RTAS extended event log.
1017 * @log: RTAS error/event log
1018 * @section_id: two character section identifier
1019 *
1020 * Returns a pointer to the specified errorlog or NULL if not found.
1021 */
1022struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
1023					      uint16_t section_id)
1024{
1025	struct rtas_ext_event_log_v6 *ext_log =
1026		(struct rtas_ext_event_log_v6 *)log->buffer;
1027	struct pseries_errorlog *sect;
1028	unsigned char *p, *log_end;
1029	uint32_t ext_log_length = rtas_error_extended_log_length(log);
1030	uint8_t log_format = rtas_ext_event_log_format(ext_log);
1031	uint32_t company_id = rtas_ext_event_company_id(ext_log);
1032
1033	/* Check that we understand the format */
1034	if (ext_log_length < sizeof(struct rtas_ext_event_log_v6) ||
1035	    log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
1036	    company_id != RTAS_V6EXT_COMPANY_ID_IBM)
1037		return NULL;
1038
1039	log_end = log->buffer + ext_log_length;
1040	p = ext_log->vendor_log;
1041
1042	while (p < log_end) {
1043		sect = (struct pseries_errorlog *)p;
1044		if (pseries_errorlog_id(sect) == section_id)
1045			return sect;
1046		p += pseries_errorlog_length(sect);
1047	}
1048
1049	return NULL;
1050}
1051
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1052/* We assume to be passed big endian arguments */
1053asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
1054{
1055	struct rtas_args args;
1056	unsigned long flags;
1057	char *buff_copy, *errbuf = NULL;
1058	int nargs, nret, token;
1059
1060	if (!capable(CAP_SYS_ADMIN))
1061		return -EPERM;
1062
1063	if (!rtas.entry)
1064		return -EINVAL;
1065
1066	if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
1067		return -EFAULT;
1068
1069	nargs = be32_to_cpu(args.nargs);
1070	nret  = be32_to_cpu(args.nret);
1071	token = be32_to_cpu(args.token);
1072
1073	if (nargs >= ARRAY_SIZE(args.args)
1074	    || nret > ARRAY_SIZE(args.args)
1075	    || nargs + nret > ARRAY_SIZE(args.args))
1076		return -EINVAL;
1077
1078	/* Copy in args. */
1079	if (copy_from_user(args.args, uargs->args,
1080			   nargs * sizeof(rtas_arg_t)) != 0)
1081		return -EFAULT;
1082
1083	if (token == RTAS_UNKNOWN_SERVICE)
1084		return -EINVAL;
1085
1086	args.rets = &args.args[nargs];
1087	memset(args.rets, 0, nret * sizeof(rtas_arg_t));
1088
 
 
 
1089	/* Need to handle ibm,suspend_me call specially */
1090	if (token == ibm_suspend_me_token) {
1091
1092		/*
1093		 * rtas_ibm_suspend_me assumes the streamid handle is in cpu
1094		 * endian, or at least the hcall within it requires it.
1095		 */
1096		int rc = 0;
1097		u64 handle = ((u64)be32_to_cpu(args.args[0]) << 32)
1098		              | be32_to_cpu(args.args[1]);
1099		rc = rtas_ibm_suspend_me(handle);
1100		if (rc == -EAGAIN)
1101			args.rets[0] = cpu_to_be32(RTAS_NOT_SUSPENDABLE);
1102		else if (rc == -EIO)
1103			args.rets[0] = cpu_to_be32(-1);
1104		else if (rc)
1105			return rc;
1106		goto copy_return;
1107	}
1108
1109	buff_copy = get_errorlog_buffer();
1110
1111	flags = lock_rtas();
1112
1113	rtas.args = args;
1114	enter_rtas(__pa(&rtas.args));
1115	args = rtas.args;
1116
1117	/* A -1 return code indicates that the last command couldn't
1118	   be completed due to a hardware error. */
1119	if (be32_to_cpu(args.rets[0]) == -1)
1120		errbuf = __fetch_rtas_last_error(buff_copy);
1121
1122	unlock_rtas(flags);
1123
1124	if (buff_copy) {
1125		if (errbuf)
1126			log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
1127		kfree(buff_copy);
1128	}
1129
1130 copy_return:
1131	/* Copy out args. */
1132	if (copy_to_user(uargs->args + nargs,
1133			 args.args + nargs,
1134			 nret * sizeof(rtas_arg_t)) != 0)
1135		return -EFAULT;
1136
1137	return 0;
1138}
1139
1140/*
1141 * Call early during boot, before mem init, to retrieve the RTAS
1142 * information from the device-tree and allocate the RMO buffer for userland
1143 * accesses.
1144 */
1145void __init rtas_initialize(void)
1146{
1147	unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
 
 
1148
1149	/* Get RTAS dev node and fill up our "rtas" structure with infos
1150	 * about it.
1151	 */
1152	rtas.dev = of_find_node_by_name(NULL, "rtas");
1153	if (rtas.dev) {
1154		const __be32 *basep, *entryp, *sizep;
1155
1156		basep = of_get_property(rtas.dev, "linux,rtas-base", NULL);
1157		sizep = of_get_property(rtas.dev, "rtas-size", NULL);
1158		if (basep != NULL && sizep != NULL) {
1159			rtas.base = __be32_to_cpu(*basep);
1160			rtas.size = __be32_to_cpu(*sizep);
1161			entryp = of_get_property(rtas.dev,
1162					"linux,rtas-entry", NULL);
1163			if (entryp == NULL) /* Ugh */
1164				rtas.entry = rtas.base;
1165			else
1166				rtas.entry = __be32_to_cpu(*entryp);
1167		} else
1168			rtas.dev = NULL;
1169	}
1170	if (!rtas.dev)
1171		return;
 
 
 
1172
1173	/* If RTAS was found, allocate the RMO buffer for it and look for
1174	 * the stop-self token if any
1175	 */
1176#ifdef CONFIG_PPC64
1177	if (firmware_has_feature(FW_FEATURE_LPAR)) {
1178		rtas_region = min(ppc64_rma_size, RTAS_INSTANTIATE_MAX);
1179		ibm_suspend_me_token = rtas_token("ibm,suspend-me");
1180	}
1181#endif
1182	rtas_rmo_buf = memblock_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
 
 
 
 
1183
1184#ifdef CONFIG_RTAS_ERROR_LOGGING
1185	rtas_last_error_token = rtas_token("rtas-last-error");
1186#endif
 
 
1187}
1188
1189int __init early_init_dt_scan_rtas(unsigned long node,
1190		const char *uname, int depth, void *data)
1191{
1192	const u32 *basep, *entryp, *sizep;
1193
1194	if (depth != 1 || strcmp(uname, "rtas") != 0)
1195		return 0;
1196
1197	basep  = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
1198	entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
1199	sizep  = of_get_flat_dt_prop(node, "rtas-size", NULL);
1200
1201	if (basep && entryp && sizep) {
1202		rtas.base = *basep;
1203		rtas.entry = *entryp;
1204		rtas.size = *sizep;
1205	}
1206
1207#ifdef CONFIG_UDBG_RTAS_CONSOLE
1208	basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
1209	if (basep)
1210		rtas_putchar_token = *basep;
1211
1212	basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
1213	if (basep)
1214		rtas_getchar_token = *basep;
1215
1216	if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
1217	    rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
1218		udbg_init_rtas_console();
1219
1220#endif
1221
1222	/* break now */
1223	return 1;
1224}
1225
1226static arch_spinlock_t timebase_lock;
1227static u64 timebase = 0;
1228
1229void rtas_give_timebase(void)
1230{
1231	unsigned long flags;
1232
1233	local_irq_save(flags);
1234	hard_irq_disable();
1235	arch_spin_lock(&timebase_lock);
1236	rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
1237	timebase = get_tb();
1238	arch_spin_unlock(&timebase_lock);
1239
1240	while (timebase)
1241		barrier();
1242	rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
1243	local_irq_restore(flags);
1244}
1245
1246void rtas_take_timebase(void)
1247{
1248	while (!timebase)
1249		barrier();
1250	arch_spin_lock(&timebase_lock);
1251	set_tb(timebase >> 32, timebase & 0xffffffff);
1252	timebase = 0;
1253	arch_spin_unlock(&timebase_lock);
1254}