arch/powerpc/kernel/rtas.c

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

DEFINITIONS
