xref: /qemu/hw/acpi/core.c (revision de4c2dcf7fedf5fa727113e1dec0d0e5dd0462a0)
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 bool acpi_table_builtin = false;
313 
314 void acpi_table_add_builtin(const QemuOpts *opts, Error **errp)
315 {
316     acpi_table_builtin = true;
317     acpi_table_add(opts, errp);
318 }
319 
320 unsigned acpi_table_len(void *current)
321 {
322     struct acpi_table_header *hdr = current - sizeof(hdr->_length);
323     return hdr->_length;
324 }
325 
326 static
327 void *acpi_table_hdr(void *h)
328 {
329     struct acpi_table_header *hdr = h;
330     return &hdr->sig;
331 }
332 
333 uint8_t *acpi_table_first(void)
334 {
335     if (acpi_table_builtin || !acpi_tables) {
336         return NULL;
337     }
338     return acpi_table_hdr(acpi_tables + ACPI_TABLE_PFX_SIZE);
339 }
340 
341 uint8_t *acpi_table_next(uint8_t *current)
342 {
343     uint8_t *next = current + acpi_table_len(current);
344 
345     if (next - acpi_tables >= acpi_tables_len) {
346         return NULL;
347     } else {
348         return acpi_table_hdr(next);
349     }
350 }
351 
352 static void acpi_notify_wakeup(Notifier *notifier, void *data)
353 {
354     ACPIREGS *ar = container_of(notifier, ACPIREGS, wakeup);
355     WakeupReason *reason = data;
356 
357     switch (*reason) {
358     case QEMU_WAKEUP_REASON_RTC:
359         ar->pm1.evt.sts |=
360             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_RT_CLOCK_STATUS);
361         break;
362     case QEMU_WAKEUP_REASON_PMTIMER:
363         ar->pm1.evt.sts |=
364             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_TIMER_STATUS);
365         break;
366     case QEMU_WAKEUP_REASON_OTHER:
367         /* ACPI_BITMASK_WAKE_STATUS should be set on resume.
368            Pretend that resume was caused by power button */
369         ar->pm1.evt.sts |=
370             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_POWER_BUTTON_STATUS);
371         break;
372     default:
373         break;
374     }
375 }
376 
377 /* ACPI PM1a EVT */
378 uint16_t acpi_pm1_evt_get_sts(ACPIREGS *ar)
379 {
380     int64_t d = acpi_pm_tmr_get_clock();
381     if (d >= ar->tmr.overflow_time) {
382         ar->pm1.evt.sts |= ACPI_BITMASK_TIMER_STATUS;
383     }
384     return ar->pm1.evt.sts;
385 }
386 
387 static void acpi_pm1_evt_write_sts(ACPIREGS *ar, uint16_t val)
388 {
389     uint16_t pm1_sts = acpi_pm1_evt_get_sts(ar);
390     if (pm1_sts & val & ACPI_BITMASK_TIMER_STATUS) {
391         /* if TMRSTS is reset, then compute the new overflow time */
392         acpi_pm_tmr_calc_overflow_time(ar);
393     }
394     ar->pm1.evt.sts &= ~val;
395 }
396 
397 static void acpi_pm1_evt_write_en(ACPIREGS *ar, uint16_t val)
398 {
399     ar->pm1.evt.en = val;
400     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC,
401                               val & ACPI_BITMASK_RT_CLOCK_ENABLE);
402     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER,
403                               val & ACPI_BITMASK_TIMER_ENABLE);
404 }
405 
406 void acpi_pm1_evt_power_down(ACPIREGS *ar)
407 {
408     if (ar->pm1.evt.en & ACPI_BITMASK_POWER_BUTTON_ENABLE) {
409         ar->pm1.evt.sts |= ACPI_BITMASK_POWER_BUTTON_STATUS;
410         ar->tmr.update_sci(ar);
411     }
412 }
413 
414 void acpi_pm1_evt_reset(ACPIREGS *ar)
415 {
416     ar->pm1.evt.sts = 0;
417     ar->pm1.evt.en = 0;
418     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC, 0);
419     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER, 0);
420 }
421 
422 static uint64_t acpi_pm_evt_read(void *opaque, hwaddr addr, unsigned width)
423 {
424     ACPIREGS *ar = opaque;
425     switch (addr) {
426     case 0:
427         return acpi_pm1_evt_get_sts(ar);
428     case 2:
429         return ar->pm1.evt.en;
430     default:
431         return 0;
432     }
433 }
434 
435 static void acpi_pm_evt_write(void *opaque, hwaddr addr, uint64_t val,
436                               unsigned width)
437 {
438     ACPIREGS *ar = opaque;
439     switch (addr) {
440     case 0:
441         acpi_pm1_evt_write_sts(ar, val);
442         ar->pm1.evt.update_sci(ar);
443         break;
444     case 2:
445         acpi_pm1_evt_write_en(ar, val);
446         ar->pm1.evt.update_sci(ar);
447         break;
448     }
449 }
450 
451 static const MemoryRegionOps acpi_pm_evt_ops = {
452     .read = acpi_pm_evt_read,
453     .write = acpi_pm_evt_write,
454     .valid.min_access_size = 2,
455     .valid.max_access_size = 2,
456     .endianness = DEVICE_LITTLE_ENDIAN,
457 };
458 
459 void acpi_pm1_evt_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
460                        MemoryRegion *parent)
461 {
462     ar->pm1.evt.update_sci = update_sci;
463     memory_region_init_io(&ar->pm1.evt.io, memory_region_owner(parent),
464                           &acpi_pm_evt_ops, ar, "acpi-evt", 4);
465     memory_region_add_subregion(parent, 0, &ar->pm1.evt.io);
466 }
467 
468 /* ACPI PM_TMR */
469 void acpi_pm_tmr_update(ACPIREGS *ar, bool enable)
470 {
471     int64_t expire_time;
472 
473     /* schedule a timer interruption if needed */
474     if (enable) {
475         expire_time = muldiv64(ar->tmr.overflow_time, get_ticks_per_sec(),
476                                PM_TIMER_FREQUENCY);
477         timer_mod(ar->tmr.timer, expire_time);
478     } else {
479         timer_del(ar->tmr.timer);
480     }
481 }
482 
483 void acpi_pm_tmr_calc_overflow_time(ACPIREGS *ar)
484 {
485     int64_t d = acpi_pm_tmr_get_clock();
486     ar->tmr.overflow_time = (d + 0x800000LL) & ~0x7fffffLL;
487 }
488 
489 static uint32_t acpi_pm_tmr_get(ACPIREGS *ar)
490 {
491     uint32_t d = acpi_pm_tmr_get_clock();
492     return d & 0xffffff;
493 }
494 
495 static void acpi_pm_tmr_timer(void *opaque)
496 {
497     ACPIREGS *ar = opaque;
498     qemu_system_wakeup_request(QEMU_WAKEUP_REASON_PMTIMER);
499     ar->tmr.update_sci(ar);
500 }
501 
502 static uint64_t acpi_pm_tmr_read(void *opaque, hwaddr addr, unsigned width)
503 {
504     return acpi_pm_tmr_get(opaque);
505 }
506 
507 static void acpi_pm_tmr_write(void *opaque, hwaddr addr, uint64_t val,
508                               unsigned width)
509 {
510     /* nothing */
511 }
512 
513 static const MemoryRegionOps acpi_pm_tmr_ops = {
514     .read = acpi_pm_tmr_read,
515     .write = acpi_pm_tmr_write,
516     .valid.min_access_size = 4,
517     .valid.max_access_size = 4,
518     .endianness = DEVICE_LITTLE_ENDIAN,
519 };
520 
521 void acpi_pm_tmr_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
522                       MemoryRegion *parent)
523 {
524     ar->tmr.update_sci = update_sci;
525     ar->tmr.timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, acpi_pm_tmr_timer, ar);
526     memory_region_init_io(&ar->tmr.io, memory_region_owner(parent),
527                           &acpi_pm_tmr_ops, ar, "acpi-tmr", 4);
528     memory_region_add_subregion(parent, 8, &ar->tmr.io);
529 }
530 
531 void acpi_pm_tmr_reset(ACPIREGS *ar)
532 {
533     ar->tmr.overflow_time = 0;
534     timer_del(ar->tmr.timer);
535 }
536 
537 /* ACPI PM1aCNT */
538 static void acpi_pm1_cnt_write(ACPIREGS *ar, uint16_t val)
539 {
540     ar->pm1.cnt.cnt = val & ~(ACPI_BITMASK_SLEEP_ENABLE);
541 
542     if (val & ACPI_BITMASK_SLEEP_ENABLE) {
543         /* change suspend type */
544         uint16_t sus_typ = (val >> 10) & 7;
545         switch(sus_typ) {
546         case 0: /* soft power off */
547             qemu_system_shutdown_request();
548             break;
549         case 1:
550             qemu_system_suspend_request();
551             break;
552         default:
553             if (sus_typ == ar->pm1.cnt.s4_val) { /* S4 request */
554                 monitor_protocol_event(QEVENT_SUSPEND_DISK, NULL);
555                 qemu_system_shutdown_request();
556             }
557             break;
558         }
559     }
560 }
561 
562 void acpi_pm1_cnt_update(ACPIREGS *ar,
563                          bool sci_enable, bool sci_disable)
564 {
565     /* ACPI specs 3.0, 4.7.2.5 */
566     if (sci_enable) {
567         ar->pm1.cnt.cnt |= ACPI_BITMASK_SCI_ENABLE;
568     } else if (sci_disable) {
569         ar->pm1.cnt.cnt &= ~ACPI_BITMASK_SCI_ENABLE;
570     }
571 }
572 
573 static uint64_t acpi_pm_cnt_read(void *opaque, hwaddr addr, unsigned width)
574 {
575     ACPIREGS *ar = opaque;
576     return ar->pm1.cnt.cnt;
577 }
578 
579 static void acpi_pm_cnt_write(void *opaque, hwaddr addr, uint64_t val,
580                               unsigned width)
581 {
582     acpi_pm1_cnt_write(opaque, val);
583 }
584 
585 static const MemoryRegionOps acpi_pm_cnt_ops = {
586     .read = acpi_pm_cnt_read,
587     .write = acpi_pm_cnt_write,
588     .valid.min_access_size = 2,
589     .valid.max_access_size = 2,
590     .endianness = DEVICE_LITTLE_ENDIAN,
591 };
592 
593 void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, uint8_t s4_val)
594 {
595     ar->pm1.cnt.s4_val = s4_val;
596     ar->wakeup.notify = acpi_notify_wakeup;
597     qemu_register_wakeup_notifier(&ar->wakeup);
598     memory_region_init_io(&ar->pm1.cnt.io, memory_region_owner(parent),
599                           &acpi_pm_cnt_ops, ar, "acpi-cnt", 2);
600     memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io);
601 }
602 
603 void acpi_pm1_cnt_reset(ACPIREGS *ar)
604 {
605     ar->pm1.cnt.cnt = 0;
606 }
607 
608 /* ACPI GPE */
609 void acpi_gpe_init(ACPIREGS *ar, uint8_t len)
610 {
611     ar->gpe.len = len;
612     ar->gpe.sts = g_malloc0(len / 2);
613     ar->gpe.en = g_malloc0(len / 2);
614 }
615 
616 void acpi_gpe_reset(ACPIREGS *ar)
617 {
618     memset(ar->gpe.sts, 0, ar->gpe.len / 2);
619     memset(ar->gpe.en, 0, ar->gpe.len / 2);
620 }
621 
622 static uint8_t *acpi_gpe_ioport_get_ptr(ACPIREGS *ar, uint32_t addr)
623 {
624     uint8_t *cur = NULL;
625 
626     if (addr < ar->gpe.len / 2) {
627         cur = ar->gpe.sts + addr;
628     } else if (addr < ar->gpe.len) {
629         cur = ar->gpe.en + addr - ar->gpe.len / 2;
630     } else {
631         abort();
632     }
633 
634     return cur;
635 }
636 
637 void acpi_gpe_ioport_writeb(ACPIREGS *ar, uint32_t addr, uint32_t val)
638 {
639     uint8_t *cur;
640 
641     cur = acpi_gpe_ioport_get_ptr(ar, addr);
642     if (addr < ar->gpe.len / 2) {
643         /* GPE_STS */
644         *cur = (*cur) & ~val;
645     } else if (addr < ar->gpe.len) {
646         /* GPE_EN */
647         *cur = val;
648     } else {
649         abort();
650     }
651 }
652 
653 uint32_t acpi_gpe_ioport_readb(ACPIREGS *ar, uint32_t addr)
654 {
655     uint8_t *cur;
656     uint32_t val;
657 
658     cur = acpi_gpe_ioport_get_ptr(ar, addr);
659     val = 0;
660     if (cur != NULL) {
661         val = *cur;
662     }
663 
664     return val;
665 }
666