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