hw/acpi/core.c

   1 /*
   2  * ACPI implementation
   3  *
   4  * Copyright (c) 2006 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License version 2 as published by the Free Software Foundation.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, see <http://www.gnu.org/licenses/>
  17  *
  18  * Contributions after 2012-01-13 are licensed under the terms of the
  19  * GNU GPL, version 2 or (at your option) any later version.
  20  */
  21 #include "sysemu/sysemu.h"
  22 #include "hw/hw.h"
  23 #include "hw/i386/pc.h"
  24 #include "hw/acpi/acpi.h"
  25 #include "monitor/monitor.h"
  26 #include "qemu/config-file.h"
  27 #include "qapi/opts-visitor.h"
  28 #include "qapi/dealloc-visitor.h"
  29 #include "qapi-visit.h"
  30
  31 struct acpi_table_header {
  32     uint16_t _length;         /* our length, not actual part of the hdr */
  33                               /* allows easier parsing for fw_cfg clients */
  34     char sig[4];              /* ACPI signature (4 ASCII characters) */
  35     uint32_t length;          /* Length of table, in bytes, including header */
  36     uint8_t revision;         /* ACPI Specification minor version # */
  37     uint8_t checksum;         /* To make sum of entire table == 0 */
  38     char oem_id[6];           /* OEM identification */
  39     char oem_table_id[8];     /* OEM table identification */
  40     uint32_t oem_revision;    /* OEM revision number */
  41     char asl_compiler_id[4];  /* ASL compiler vendor ID */
  42     uint32_t asl_compiler_revision; /* ASL compiler revision number */
  43 } QEMU_PACKED;
  44
  45 #define ACPI_TABLE_HDR_SIZE sizeof(struct acpi_table_header)
  46 #define ACPI_TABLE_PFX_SIZE sizeof(uint16_t)  /* size of the extra prefix */
  47
  48 static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE - ACPI_TABLE_PFX_SIZE] =
  49     "QEMU\0\0\0\0\1\0"       /* sig (4), len(4), revno (1), csum (1) */
  50     "QEMUQEQEMUQEMU\1\0\0\0" /* OEM id (6), table (8), revno (4) */
  51     "QEMU\1\0\0\0"           /* ASL compiler ID (4), version (4) */
  52     ;
  53
  54 char unsigned *acpi_tables;
  55 size_t acpi_tables_len;
  56
  57 static QemuOptsList qemu_acpi_opts = {
  58     .name = "acpi",
  59     .implied_opt_name = "data",
  60     .head = QTAILQ_HEAD_INITIALIZER(qemu_acpi_opts.head),
  61     .desc = { { 0 } } /* validated with OptsVisitor */
  62 };
  63
  64 static void acpi_register_config(void)
  65 {
  66     qemu_add_opts(&qemu_acpi_opts);
  67 }
  68
  69 machine_init(acpi_register_config);
  70
  71 static int acpi_checksum(const uint8_t *data, int len)
  72 {
  73     int sum, i;
  74     sum = 0;
  75     for (i = 0; i < len; i++) {
  76         sum += data[i];
  77     }
  78     return (-sum) & 0xff;
  79 }
  80
  81
  82 /* Install a copy of the ACPI table specified in @blob.
  83  *
  84  * If @has_header is set, @blob starts with the System Description Table Header
  85  * structure. Otherwise, "dfl_hdr" is prepended. In any case, each header field
  86  * is optionally overwritten from @hdrs.
  87  *
  88  * It is valid to call this function with
  89  * (@blob == NULL && bloblen == 0 && !has_header).
  90  *
  91  * @hdrs->file and @hdrs->data are ignored.
  92  *
  93  * SIZE_MAX is considered "infinity" in this function.
  94  *
  95  * The number of tables that can be installed is not limited, but the 16-bit
  96  * counter at the beginning of "acpi_tables" wraps around after UINT16_MAX.
  97  */
  98 static void acpi_table_install(const char unsigned *blob, size_t bloblen,
  99                                bool has_header,
 100                                const struct AcpiTableOptions *hdrs,
 101                                Error **errp)
 102 {
 103     size_t body_start;
 104     const char unsigned *hdr_src;
 105     size_t body_size, acpi_payload_size;
 106     struct acpi_table_header *ext_hdr;
 107     unsigned changed_fields;
 108
 109     /* Calculate where the ACPI table body starts within the blob, plus where
 110      * to copy the ACPI table header from.
 111      */
 112     if (has_header) {
 113         /*   _length             | ACPI header in blob | blob body
 114          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^
 115          *   ACPI_TABLE_PFX_SIZE     sizeof dfl_hdr      body_size
 116          *                           == body_start
 117          *
 118          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 119          *                           acpi_payload_size == bloblen
 120          */
 121         body_start = sizeof dfl_hdr;
 122
 123         if (bloblen < body_start) {
 124             error_setg(errp, "ACPI table claiming to have header is too "
 125                        "short, available: %zu, expected: %zu", bloblen,
 126                        body_start);
 127             return;
 128         }
 129         hdr_src = blob;
 130     } else {
 131         /*   _length             | ACPI header in template | blob body
 132          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^
 133          *   ACPI_TABLE_PFX_SIZE       sizeof dfl_hdr        body_size
 134          *                                                   == bloblen
 135          *
 136          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 137          *                                  acpi_payload_size
 138          */
 139         body_start = 0;
 140         hdr_src = dfl_hdr;
 141     }
 142     body_size = bloblen - body_start;
 143     acpi_payload_size = sizeof dfl_hdr + body_size;
 144
 145     if (acpi_payload_size > UINT16_MAX) {
 146         error_setg(errp, "ACPI table too big, requested: %zu, max: %u",
 147                    acpi_payload_size, (unsigned)UINT16_MAX);
 148         return;
 149     }
 150
 151     /* We won't fail from here on. Initialize / extend the globals. */
 152     if (acpi_tables == NULL) {
 153         acpi_tables_len = sizeof(uint16_t);
 154         acpi_tables = g_malloc0(acpi_tables_len);
 155     }
 156
 157     acpi_tables = g_realloc(acpi_tables, acpi_tables_len +
 158                                          ACPI_TABLE_PFX_SIZE +
 159                                          sizeof dfl_hdr + body_size);
 160
 161     ext_hdr = (struct acpi_table_header *)(acpi_tables + acpi_tables_len);
 162     acpi_tables_len += ACPI_TABLE_PFX_SIZE;
 163
 164     memcpy(acpi_tables + acpi_tables_len, hdr_src, sizeof dfl_hdr);
 165     acpi_tables_len += sizeof dfl_hdr;
 166
 167     if (blob != NULL) {
 168         memcpy(acpi_tables + acpi_tables_len, blob + body_start, body_size);
 169         acpi_tables_len += body_size;
 170     }
 171
 172     /* increase number of tables */
 173     cpu_to_le16wu((uint16_t *)acpi_tables,
 174                   le16_to_cpupu((uint16_t *)acpi_tables) + 1u);
 175
 176     /* Update the header fields. The strings need not be NUL-terminated. */
 177     changed_fields = 0;
 178     ext_hdr->_length = cpu_to_le16(acpi_payload_size);
 179
 180     if (hdrs->has_sig) {
 181         strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig);
 182         ++changed_fields;
 183     }
 184
 185     if (has_header && le32_to_cpu(ext_hdr->length) != acpi_payload_size) {
 186         fprintf(stderr,
 187                 "warning: ACPI table has wrong length, header says "
 188                 "%" PRIu32 ", actual size %zu bytes\n",
 189                 le32_to_cpu(ext_hdr->length), acpi_payload_size);
 190     }
 191     ext_hdr->length = cpu_to_le32(acpi_payload_size);
 192
 193     if (hdrs->has_rev) {
 194         ext_hdr->revision = hdrs->rev;
 195         ++changed_fields;
 196     }
 197
 198     ext_hdr->checksum = 0;
 199
 200     if (hdrs->has_oem_id) {
 201         strncpy(ext_hdr->oem_id, hdrs->oem_id, sizeof ext_hdr->oem_id);
 202         ++changed_fields;
 203     }
 204     if (hdrs->has_oem_table_id) {
 205         strncpy(ext_hdr->oem_table_id, hdrs->oem_table_id,
 206                 sizeof ext_hdr->oem_table_id);
 207         ++changed_fields;
 208     }
 209     if (hdrs->has_oem_rev) {
 210         ext_hdr->oem_revision = cpu_to_le32(hdrs->oem_rev);
 211         ++changed_fields;
 212     }
 213     if (hdrs->has_asl_compiler_id) {
 214         strncpy(ext_hdr->asl_compiler_id, hdrs->asl_compiler_id,
 215                 sizeof ext_hdr->asl_compiler_id);
 216         ++changed_fields;
 217     }
 218     if (hdrs->has_asl_compiler_rev) {
 219         ext_hdr->asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev);
 220         ++changed_fields;
 221     }
 222
 223     if (!has_header && changed_fields == 0) {
 224         fprintf(stderr, "warning: ACPI table: no headers are specified\n");
 225     }
 226
 227     /* recalculate checksum */
 228     ext_hdr->checksum = acpi_checksum((const char unsigned *)ext_hdr +
 229                                       ACPI_TABLE_PFX_SIZE, acpi_payload_size);
 230 }
 231
 232 void acpi_table_add(const QemuOpts *opts, Error **errp)
 233 {
 234     AcpiTableOptions *hdrs = NULL;
 235     Error *err = NULL;
 236     char **pathnames = NULL;
 237     char **cur;
 238     size_t bloblen = 0;
 239     char unsigned *blob = NULL;
 240
 241     {
 242         OptsVisitor *ov;
 243
 244         ov = opts_visitor_new(opts);
 245         visit_type_AcpiTableOptions(opts_get_visitor(ov), &hdrs, NULL, &err);
 246         opts_visitor_cleanup(ov);
 247     }
 248
 249     if (err) {
 250         goto out;
 251     }
 252     if (hdrs->has_file == hdrs->has_data) {
 253         error_setg(&err, "'-acpitable' requires one of 'data' or 'file'");
 254         goto out;
 255     }
 256
 257     pathnames = g_strsplit(hdrs->has_file ? hdrs->file : hdrs->data, ":", 0);
 258     if (pathnames == NULL || pathnames[0] == NULL) {
 259         error_setg(&err, "'-acpitable' requires at least one pathname");
 260         goto out;
 261     }
 262
 263     /* now read in the data files, reallocating buffer as needed */
 264     for (cur = pathnames; *cur; ++cur) {
 265         int fd = open(*cur, O_RDONLY | O_BINARY);
 266
 267         if (fd < 0) {
 268             error_setg(&err, "can't open file %s: %s", *cur, strerror(errno));
 269             goto out;
 270         }
 271
 272         for (;;) {
 273             char unsigned data[8192];
 274             ssize_t r;
 275
 276             r = read(fd, data, sizeof data);
 277             if (r == 0) {
 278                 break;
 279             } else if (r > 0) {
 280                 blob = g_realloc(blob, bloblen + r);
 281                 memcpy(blob + bloblen, data, r);
 282                 bloblen += r;
 283             } else if (errno != EINTR) {
 284                 error_setg(&err, "can't read file %s: %s",
 285                            *cur, strerror(errno));
 286                 close(fd);
 287                 goto out;
 288             }
 289         }
 290
 291         close(fd);
 292     }
 293
 294     acpi_table_install(blob, bloblen, hdrs->has_file, hdrs, &err);
 295
 296 out:
 297     g_free(blob);
 298     g_strfreev(pathnames);
 299
 300     if (hdrs != NULL) {
 301         QapiDeallocVisitor *dv;
 302
 303         dv = qapi_dealloc_visitor_new();
 304         visit_type_AcpiTableOptions(qapi_dealloc_get_visitor(dv), &hdrs, NULL,
 305                                     NULL);
 306         qapi_dealloc_visitor_cleanup(dv);
 307     }
 308
 309     error_propagate(errp, err);
 310 }
 311
 312 static void acpi_notify_wakeup(Notifier *notifier, void *data)
 313 {
 314     ACPIREGS *ar = container_of(notifier, ACPIREGS, wakeup);
 315     WakeupReason *reason = data;
 316
 317     switch (*reason) {
 318     case QEMU_WAKEUP_REASON_RTC:
 319         ar->pm1.evt.sts |=
 320             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_RT_CLOCK_STATUS);
 321         break;
 322     case QEMU_WAKEUP_REASON_PMTIMER:
 323         ar->pm1.evt.sts |=
 324             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_TIMER_STATUS);
 325         break;
 326     case QEMU_WAKEUP_REASON_OTHER:
 327     default:
 328         /* ACPI_BITMASK_WAKE_STATUS should be set on resume.
 329            Pretend that resume was caused by power button */
 330         ar->pm1.evt.sts |=
 331             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_POWER_BUTTON_STATUS);
 332         break;
 333     }
 334 }
 335
 336 /* ACPI PM1a EVT */
 337 uint16_t acpi_pm1_evt_get_sts(ACPIREGS *ar)
 338 {
 339     int64_t d = acpi_pm_tmr_get_clock();
 340     if (d >= ar->tmr.overflow_time) {
 341         ar->pm1.evt.sts |= ACPI_BITMASK_TIMER_STATUS;
 342     }
 343     return ar->pm1.evt.sts;
 344 }
 345
 346 static void acpi_pm1_evt_write_sts(ACPIREGS *ar, uint16_t val)
 347 {
 348     uint16_t pm1_sts = acpi_pm1_evt_get_sts(ar);
 349     if (pm1_sts & val & ACPI_BITMASK_TIMER_STATUS) {
 350         /* if TMRSTS is reset, then compute the new overflow time */
 351         acpi_pm_tmr_calc_overflow_time(ar);
 352     }
 353     ar->pm1.evt.sts &= ~val;
 354 }
 355
 356 static void acpi_pm1_evt_write_en(ACPIREGS *ar, uint16_t val)
 357 {
 358     ar->pm1.evt.en = val;
 359     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC,
 360                               val & ACPI_BITMASK_RT_CLOCK_ENABLE);
 361     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER,
 362                               val & ACPI_BITMASK_TIMER_ENABLE);
 363 }
 364
 365 void acpi_pm1_evt_power_down(ACPIREGS *ar)
 366 {
 367     if (ar->pm1.evt.en & ACPI_BITMASK_POWER_BUTTON_ENABLE) {
 368         ar->pm1.evt.sts |= ACPI_BITMASK_POWER_BUTTON_STATUS;
 369         ar->tmr.update_sci(ar);
 370     }
 371 }
 372
 373 void acpi_pm1_evt_reset(ACPIREGS *ar)
 374 {
 375     ar->pm1.evt.sts = 0;
 376     ar->pm1.evt.en = 0;
 377     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC, 0);
 378     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER, 0);
 379 }
 380
 381 static uint64_t acpi_pm_evt_read(void *opaque, hwaddr addr, unsigned width)
 382 {
 383     ACPIREGS *ar = opaque;
 384     switch (addr) {
 385     case 0:
 386         return acpi_pm1_evt_get_sts(ar);
 387     case 2:
 388         return ar->pm1.evt.en;
 389     default:
 390         return 0;
 391     }
 392 }
 393
 394 static void acpi_pm_evt_write(void *opaque, hwaddr addr, uint64_t val,
 395                               unsigned width)
 396 {
 397     ACPIREGS *ar = opaque;
 398     switch (addr) {
 399     case 0:
 400         acpi_pm1_evt_write_sts(ar, val);
 401         ar->pm1.evt.update_sci(ar);
 402         break;
 403     case 2:
 404         acpi_pm1_evt_write_en(ar, val);
 405         ar->pm1.evt.update_sci(ar);
 406         break;
 407     }
 408 }
 409
 410 static const MemoryRegionOps acpi_pm_evt_ops = {
 411     .read = acpi_pm_evt_read,
 412     .write = acpi_pm_evt_write,
 413     .valid.min_access_size = 2,
 414     .valid.max_access_size = 2,
 415     .endianness = DEVICE_LITTLE_ENDIAN,
 416 };
 417
 418 void acpi_pm1_evt_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
 419                        MemoryRegion *parent)
 420 {
 421     ar->pm1.evt.update_sci = update_sci;
 422     memory_region_init_io(&ar->pm1.evt.io, &acpi_pm_evt_ops, ar, "acpi-evt", 4);
 423     memory_region_add_subregion(parent, 0, &ar->pm1.evt.io);
 424 }
 425
 426 /* ACPI PM_TMR */
 427 void acpi_pm_tmr_update(ACPIREGS *ar, bool enable)
 428 {
 429     int64_t expire_time;
 430
 431     /* schedule a timer interruption if needed */
 432     if (enable) {
 433         expire_time = muldiv64(ar->tmr.overflow_time, get_ticks_per_sec(),
 434                                PM_TIMER_FREQUENCY);
 435         qemu_mod_timer(ar->tmr.timer, expire_time);
 436     } else {
 437         qemu_del_timer(ar->tmr.timer);
 438     }
 439 }
 440
 441 void acpi_pm_tmr_calc_overflow_time(ACPIREGS *ar)
 442 {
 443     int64_t d = acpi_pm_tmr_get_clock();
 444     ar->tmr.overflow_time = (d + 0x800000LL) & ~0x7fffffLL;
 445 }
 446
 447 static uint32_t acpi_pm_tmr_get(ACPIREGS *ar)
 448 {
 449     uint32_t d = acpi_pm_tmr_get_clock();
 450     return d & 0xffffff;
 451 }
 452
 453 static void acpi_pm_tmr_timer(void *opaque)
 454 {
 455     ACPIREGS *ar = opaque;
 456     qemu_system_wakeup_request(QEMU_WAKEUP_REASON_PMTIMER);
 457     ar->tmr.update_sci(ar);
 458 }
 459
 460 static uint64_t acpi_pm_tmr_read(void *opaque, hwaddr addr, unsigned width)
 461 {
 462     return acpi_pm_tmr_get(opaque);
 463 }
 464
 465 static const MemoryRegionOps acpi_pm_tmr_ops = {
 466     .read = acpi_pm_tmr_read,
 467     .valid.min_access_size = 4,
 468     .valid.max_access_size = 4,
 469     .endianness = DEVICE_LITTLE_ENDIAN,
 470 };
 471
 472 void acpi_pm_tmr_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
 473                       MemoryRegion *parent)
 474 {
 475     ar->tmr.update_sci = update_sci;
 476     ar->tmr.timer = qemu_new_timer_ns(vm_clock, acpi_pm_tmr_timer, ar);
 477     memory_region_init_io(&ar->tmr.io, &acpi_pm_tmr_ops, ar, "acpi-tmr", 4);
 478     memory_region_add_subregion(parent, 8, &ar->tmr.io);
 479 }
 480
 481 void acpi_pm_tmr_reset(ACPIREGS *ar)
 482 {
 483     ar->tmr.overflow_time = 0;
 484     qemu_del_timer(ar->tmr.timer);
 485 }
 486
 487 /* ACPI PM1aCNT */
 488 static void acpi_pm1_cnt_write(ACPIREGS *ar, uint16_t val)
 489 {
 490     ar->pm1.cnt.cnt = val & ~(ACPI_BITMASK_SLEEP_ENABLE);
 491
 492     if (val & ACPI_BITMASK_SLEEP_ENABLE) {
 493         /* change suspend type */
 494         uint16_t sus_typ = (val >> 10) & 7;
 495         switch(sus_typ) {
 496         case 0: /* soft power off */
 497             qemu_system_shutdown_request();
 498             break;
 499         case 1:
 500             qemu_system_suspend_request();
 501             break;
 502         default:
 503             if (sus_typ == ar->pm1.cnt.s4_val) { /* S4 request */
 504                 monitor_protocol_event(QEVENT_SUSPEND_DISK, NULL);
 505                 qemu_system_shutdown_request();
 506             }
 507             break;
 508         }
 509     }
 510 }
 511
 512 void acpi_pm1_cnt_update(ACPIREGS *ar,
 513                          bool sci_enable, bool sci_disable)
 514 {
 515     /* ACPI specs 3.0, 4.7.2.5 */
 516     if (sci_enable) {
 517         ar->pm1.cnt.cnt |= ACPI_BITMASK_SCI_ENABLE;
 518     } else if (sci_disable) {
 519         ar->pm1.cnt.cnt &= ~ACPI_BITMASK_SCI_ENABLE;
 520     }
 521 }
 522
 523 static uint64_t acpi_pm_cnt_read(void *opaque, hwaddr addr, unsigned width)
 524 {
 525     ACPIREGS *ar = opaque;
 526     return ar->pm1.cnt.cnt;
 527 }
 528
 529 static void acpi_pm_cnt_write(void *opaque, hwaddr addr, uint64_t val,
 530                               unsigned width)
 531 {
 532     acpi_pm1_cnt_write(opaque, val);
 533 }
 534
 535 static const MemoryRegionOps acpi_pm_cnt_ops = {
 536     .read = acpi_pm_cnt_read,
 537     .write = acpi_pm_cnt_write,
 538     .valid.min_access_size = 2,
 539     .valid.max_access_size = 2,
 540     .endianness = DEVICE_LITTLE_ENDIAN,
 541 };
 542
 543 void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, uint8_t s4_val)
 544 {
 545     ar->pm1.cnt.s4_val = s4_val;
 546     ar->wakeup.notify = acpi_notify_wakeup;
 547     qemu_register_wakeup_notifier(&ar->wakeup);
 548     memory_region_init_io(&ar->pm1.cnt.io, &acpi_pm_cnt_ops, ar, "acpi-cnt", 2);
 549     memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io);
 550 }
 551
 552 void acpi_pm1_cnt_reset(ACPIREGS *ar)
 553 {
 554     ar->pm1.cnt.cnt = 0;
 555 }
 556
 557 /* ACPI GPE */
 558 void acpi_gpe_init(ACPIREGS *ar, uint8_t len)
 559 {
 560     ar->gpe.len = len;
 561     ar->gpe.sts = g_malloc0(len / 2);
 562     ar->gpe.en = g_malloc0(len / 2);
 563 }
 564
 565 void acpi_gpe_reset(ACPIREGS *ar)
 566 {
 567     memset(ar->gpe.sts, 0, ar->gpe.len / 2);
 568     memset(ar->gpe.en, 0, ar->gpe.len / 2);
 569 }
 570
 571 static uint8_t *acpi_gpe_ioport_get_ptr(ACPIREGS *ar, uint32_t addr)
 572 {
 573     uint8_t *cur = NULL;
 574
 575     if (addr < ar->gpe.len / 2) {
 576         cur = ar->gpe.sts + addr;
 577     } else if (addr < ar->gpe.len) {
 578         cur = ar->gpe.en + addr - ar->gpe.len / 2;
 579     } else {
 580         abort();
 581     }
 582
 583     return cur;
 584 }
 585
 586 void acpi_gpe_ioport_writeb(ACPIREGS *ar, uint32_t addr, uint32_t val)
 587 {
 588     uint8_t *cur;
 589
 590     cur = acpi_gpe_ioport_get_ptr(ar, addr);
 591     if (addr < ar->gpe.len / 2) {
 592         /* GPE_STS */
 593         *cur = (*cur) & ~val;
 594     } else if (addr < ar->gpe.len) {
 595         /* GPE_EN */
 596         *cur = val;
 597     } else {
 598         abort();
 599     }
 600 }
 601
 602 uint32_t acpi_gpe_ioport_readb(ACPIREGS *ar, uint32_t addr)
 603 {
 604     uint8_t *cur;
 605     uint32_t val;
 606
 607     cur = acpi_gpe_ioport_get_ptr(ar, addr);
 608     val = 0;
 609     if (cur != NULL) {
 610         val = *cur;
 611     }
 612
 613     return val;
 614 }