xref: /openbmc/qemu/hw/acpi/core.c (revision 0430891c)
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 "qemu/osdep.h"
22 #include "sysemu/sysemu.h"
23 #include "hw/hw.h"
24 #include "hw/i386/pc.h"
25 #include "hw/acpi/acpi.h"
26 #include "hw/nvram/fw_cfg.h"
27 #include "qemu/config-file.h"
28 #include "qapi/opts-visitor.h"
29 #include "qapi/dealloc-visitor.h"
30 #include "qapi-visit.h"
31 #include "qapi-event.h"
32 
33 struct acpi_table_header {
34     uint16_t _length;         /* our length, not actual part of the hdr */
35                               /* allows easier parsing for fw_cfg clients */
36     char sig[4];              /* ACPI signature (4 ASCII characters) */
37     uint32_t length;          /* Length of table, in bytes, including header */
38     uint8_t revision;         /* ACPI Specification minor version # */
39     uint8_t checksum;         /* To make sum of entire table == 0 */
40     char oem_id[6];           /* OEM identification */
41     char oem_table_id[8];     /* OEM table identification */
42     uint32_t oem_revision;    /* OEM revision number */
43     char asl_compiler_id[4];  /* ASL compiler vendor ID */
44     uint32_t asl_compiler_revision; /* ASL compiler revision number */
45 } QEMU_PACKED;
46 
47 #define ACPI_TABLE_HDR_SIZE sizeof(struct acpi_table_header)
48 #define ACPI_TABLE_PFX_SIZE sizeof(uint16_t)  /* size of the extra prefix */
49 
50 static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE - ACPI_TABLE_PFX_SIZE] =
51     "QEMU\0\0\0\0\1\0"       /* sig (4), len(4), revno (1), csum (1) */
52     "QEMUQEQEMUQEMU\1\0\0\0" /* OEM id (6), table (8), revno (4) */
53     "QEMU\1\0\0\0"           /* ASL compiler ID (4), version (4) */
54     ;
55 
56 char unsigned *acpi_tables;
57 size_t acpi_tables_len;
58 
59 static QemuOptsList qemu_acpi_opts = {
60     .name = "acpi",
61     .implied_opt_name = "data",
62     .head = QTAILQ_HEAD_INITIALIZER(qemu_acpi_opts.head),
63     .desc = { { 0 } } /* validated with OptsVisitor */
64 };
65 
66 static void acpi_register_config(void)
67 {
68     qemu_add_opts(&qemu_acpi_opts);
69 }
70 
71 machine_init(acpi_register_config);
72 
73 static int acpi_checksum(const uint8_t *data, int len)
74 {
75     int sum, i;
76     sum = 0;
77     for (i = 0; i < len; i++) {
78         sum += data[i];
79     }
80     return (-sum) & 0xff;
81 }
82 
83 
84 /* Install a copy of the ACPI table specified in @blob.
85  *
86  * If @has_header is set, @blob starts with the System Description Table Header
87  * structure. Otherwise, "dfl_hdr" is prepended. In any case, each header field
88  * is optionally overwritten from @hdrs.
89  *
90  * It is valid to call this function with
91  * (@blob == NULL && bloblen == 0 && !has_header).
92  *
93  * @hdrs->file and @hdrs->data are ignored.
94  *
95  * SIZE_MAX is considered "infinity" in this function.
96  *
97  * The number of tables that can be installed is not limited, but the 16-bit
98  * counter at the beginning of "acpi_tables" wraps around after UINT16_MAX.
99  */
100 static void acpi_table_install(const char unsigned *blob, size_t bloblen,
101                                bool has_header,
102                                const struct AcpiTableOptions *hdrs,
103                                Error **errp)
104 {
105     size_t body_start;
106     const char unsigned *hdr_src;
107     size_t body_size, acpi_payload_size;
108     struct acpi_table_header *ext_hdr;
109     unsigned changed_fields;
110 
111     /* Calculate where the ACPI table body starts within the blob, plus where
112      * to copy the ACPI table header from.
113      */
114     if (has_header) {
115         /*   _length             | ACPI header in blob | blob body
116          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^
117          *   ACPI_TABLE_PFX_SIZE     sizeof dfl_hdr      body_size
118          *                           == body_start
119          *
120          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
121          *                           acpi_payload_size == bloblen
122          */
123         body_start = sizeof dfl_hdr;
124 
125         if (bloblen < body_start) {
126             error_setg(errp, "ACPI table claiming to have header is too "
127                        "short, available: %zu, expected: %zu", bloblen,
128                        body_start);
129             return;
130         }
131         hdr_src = blob;
132     } else {
133         /*   _length             | ACPI header in template | blob body
134          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^
135          *   ACPI_TABLE_PFX_SIZE       sizeof dfl_hdr        body_size
136          *                                                   == bloblen
137          *
138          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
139          *                                  acpi_payload_size
140          */
141         body_start = 0;
142         hdr_src = dfl_hdr;
143     }
144     body_size = bloblen - body_start;
145     acpi_payload_size = sizeof dfl_hdr + body_size;
146 
147     if (acpi_payload_size > UINT16_MAX) {
148         error_setg(errp, "ACPI table too big, requested: %zu, max: %u",
149                    acpi_payload_size, (unsigned)UINT16_MAX);
150         return;
151     }
152 
153     /* We won't fail from here on. Initialize / extend the globals. */
154     if (acpi_tables == NULL) {
155         acpi_tables_len = sizeof(uint16_t);
156         acpi_tables = g_malloc0(acpi_tables_len);
157     }
158 
159     acpi_tables = g_realloc(acpi_tables, acpi_tables_len +
160                                          ACPI_TABLE_PFX_SIZE +
161                                          sizeof dfl_hdr + body_size);
162 
163     ext_hdr = (struct acpi_table_header *)(acpi_tables + acpi_tables_len);
164     acpi_tables_len += ACPI_TABLE_PFX_SIZE;
165 
166     memcpy(acpi_tables + acpi_tables_len, hdr_src, sizeof dfl_hdr);
167     acpi_tables_len += sizeof dfl_hdr;
168 
169     if (blob != NULL) {
170         memcpy(acpi_tables + acpi_tables_len, blob + body_start, body_size);
171         acpi_tables_len += body_size;
172     }
173 
174     /* increase number of tables */
175     stw_le_p(acpi_tables, lduw_le_p(acpi_tables) + 1u);
176 
177     /* Update the header fields. The strings need not be NUL-terminated. */
178     changed_fields = 0;
179     ext_hdr->_length = cpu_to_le16(acpi_payload_size);
180 
181     if (hdrs->has_sig) {
182         strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig);
183         ++changed_fields;
184     }
185 
186     if (has_header && le32_to_cpu(ext_hdr->length) != acpi_payload_size) {
187         fprintf(stderr,
188                 "warning: ACPI table has wrong length, header says "
189                 "%" PRIu32 ", actual size %zu bytes\n",
190                 le32_to_cpu(ext_hdr->length), acpi_payload_size);
191     }
192     ext_hdr->length = cpu_to_le32(acpi_payload_size);
193 
194     if (hdrs->has_rev) {
195         ext_hdr->revision = hdrs->rev;
196         ++changed_fields;
197     }
198 
199     ext_hdr->checksum = 0;
200 
201     if (hdrs->has_oem_id) {
202         strncpy(ext_hdr->oem_id, hdrs->oem_id, sizeof ext_hdr->oem_id);
203         ++changed_fields;
204     }
205     if (hdrs->has_oem_table_id) {
206         strncpy(ext_hdr->oem_table_id, hdrs->oem_table_id,
207                 sizeof ext_hdr->oem_table_id);
208         ++changed_fields;
209     }
210     if (hdrs->has_oem_rev) {
211         ext_hdr->oem_revision = cpu_to_le32(hdrs->oem_rev);
212         ++changed_fields;
213     }
214     if (hdrs->has_asl_compiler_id) {
215         strncpy(ext_hdr->asl_compiler_id, hdrs->asl_compiler_id,
216                 sizeof ext_hdr->asl_compiler_id);
217         ++changed_fields;
218     }
219     if (hdrs->has_asl_compiler_rev) {
220         ext_hdr->asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev);
221         ++changed_fields;
222     }
223 
224     if (!has_header && changed_fields == 0) {
225         fprintf(stderr, "warning: ACPI table: no headers are specified\n");
226     }
227 
228     /* recalculate checksum */
229     ext_hdr->checksum = acpi_checksum((const char unsigned *)ext_hdr +
230                                       ACPI_TABLE_PFX_SIZE, acpi_payload_size);
231 }
232 
233 void acpi_table_add(const QemuOpts *opts, Error **errp)
234 {
235     AcpiTableOptions *hdrs = NULL;
236     Error *err = NULL;
237     char **pathnames = NULL;
238     char **cur;
239     size_t bloblen = 0;
240     char unsigned *blob = NULL;
241 
242     {
243         OptsVisitor *ov;
244 
245         ov = opts_visitor_new(opts);
246         visit_type_AcpiTableOptions(opts_get_visitor(ov), &hdrs, NULL, &err);
247         opts_visitor_cleanup(ov);
248     }
249 
250     if (err) {
251         goto out;
252     }
253     if (hdrs->has_file == hdrs->has_data) {
254         error_setg(&err, "'-acpitable' requires one of 'data' or 'file'");
255         goto out;
256     }
257 
258     pathnames = g_strsplit(hdrs->has_file ? hdrs->file : hdrs->data, ":", 0);
259     if (pathnames == NULL || pathnames[0] == NULL) {
260         error_setg(&err, "'-acpitable' requires at least one pathname");
261         goto out;
262     }
263 
264     /* now read in the data files, reallocating buffer as needed */
265     for (cur = pathnames; *cur; ++cur) {
266         int fd = open(*cur, O_RDONLY | O_BINARY);
267 
268         if (fd < 0) {
269             error_setg(&err, "can't open file %s: %s", *cur, strerror(errno));
270             goto out;
271         }
272 
273         for (;;) {
274             char unsigned data[8192];
275             ssize_t r;
276 
277             r = read(fd, data, sizeof data);
278             if (r == 0) {
279                 break;
280             } else if (r > 0) {
281                 blob = g_realloc(blob, bloblen + r);
282                 memcpy(blob + bloblen, data, r);
283                 bloblen += r;
284             } else if (errno != EINTR) {
285                 error_setg(&err, "can't read file %s: %s",
286                            *cur, strerror(errno));
287                 close(fd);
288                 goto out;
289             }
290         }
291 
292         close(fd);
293     }
294 
295     acpi_table_install(blob, bloblen, hdrs->has_file, hdrs, &err);
296 
297 out:
298     g_free(blob);
299     g_strfreev(pathnames);
300 
301     if (hdrs != NULL) {
302         QapiDeallocVisitor *dv;
303 
304         dv = qapi_dealloc_visitor_new();
305         visit_type_AcpiTableOptions(qapi_dealloc_get_visitor(dv), &hdrs, NULL,
306                                     NULL);
307         qapi_dealloc_visitor_cleanup(dv);
308     }
309 
310     error_propagate(errp, err);
311 }
312 
313 static bool acpi_table_builtin = false;
314 
315 void acpi_table_add_builtin(const QemuOpts *opts, Error **errp)
316 {
317     acpi_table_builtin = true;
318     acpi_table_add(opts, errp);
319 }
320 
321 unsigned acpi_table_len(void *current)
322 {
323     struct acpi_table_header *hdr = current - sizeof(hdr->_length);
324     return hdr->_length;
325 }
326 
327 static
328 void *acpi_table_hdr(void *h)
329 {
330     struct acpi_table_header *hdr = h;
331     return &hdr->sig;
332 }
333 
334 uint8_t *acpi_table_first(void)
335 {
336     if (acpi_table_builtin || !acpi_tables) {
337         return NULL;
338     }
339     return acpi_table_hdr(acpi_tables + ACPI_TABLE_PFX_SIZE);
340 }
341 
342 uint8_t *acpi_table_next(uint8_t *current)
343 {
344     uint8_t *next = current + acpi_table_len(current);
345 
346     if (next - acpi_tables >= acpi_tables_len) {
347         return NULL;
348     } else {
349         return acpi_table_hdr(next);
350     }
351 }
352 
353 static void acpi_notify_wakeup(Notifier *notifier, void *data)
354 {
355     ACPIREGS *ar = container_of(notifier, ACPIREGS, wakeup);
356     WakeupReason *reason = data;
357 
358     switch (*reason) {
359     case QEMU_WAKEUP_REASON_RTC:
360         ar->pm1.evt.sts |=
361             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_RT_CLOCK_STATUS);
362         break;
363     case QEMU_WAKEUP_REASON_PMTIMER:
364         ar->pm1.evt.sts |=
365             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_TIMER_STATUS);
366         break;
367     case QEMU_WAKEUP_REASON_OTHER:
368         /* ACPI_BITMASK_WAKE_STATUS should be set on resume.
369            Pretend that resume was caused by power button */
370         ar->pm1.evt.sts |=
371             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_POWER_BUTTON_STATUS);
372         break;
373     default:
374         break;
375     }
376 }
377 
378 /* ACPI PM1a EVT */
379 uint16_t acpi_pm1_evt_get_sts(ACPIREGS *ar)
380 {
381     /* Compare ns-clock, not PM timer ticks, because
382        acpi_pm_tmr_update function uses ns for setting the timer. */
383     int64_t d = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
384     if (d >= muldiv64(ar->tmr.overflow_time,
385                       get_ticks_per_sec(), PM_TIMER_FREQUENCY)) {
386         ar->pm1.evt.sts |= ACPI_BITMASK_TIMER_STATUS;
387     }
388     return ar->pm1.evt.sts;
389 }
390 
391 static void acpi_pm1_evt_write_sts(ACPIREGS *ar, uint16_t val)
392 {
393     uint16_t pm1_sts = acpi_pm1_evt_get_sts(ar);
394     if (pm1_sts & val & ACPI_BITMASK_TIMER_STATUS) {
395         /* if TMRSTS is reset, then compute the new overflow time */
396         acpi_pm_tmr_calc_overflow_time(ar);
397     }
398     ar->pm1.evt.sts &= ~val;
399 }
400 
401 static void acpi_pm1_evt_write_en(ACPIREGS *ar, uint16_t val)
402 {
403     ar->pm1.evt.en = val;
404     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC,
405                               val & ACPI_BITMASK_RT_CLOCK_ENABLE);
406     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER,
407                               val & ACPI_BITMASK_TIMER_ENABLE);
408 }
409 
410 void acpi_pm1_evt_power_down(ACPIREGS *ar)
411 {
412     if (ar->pm1.evt.en & ACPI_BITMASK_POWER_BUTTON_ENABLE) {
413         ar->pm1.evt.sts |= ACPI_BITMASK_POWER_BUTTON_STATUS;
414         ar->tmr.update_sci(ar);
415     }
416 }
417 
418 void acpi_pm1_evt_reset(ACPIREGS *ar)
419 {
420     ar->pm1.evt.sts = 0;
421     ar->pm1.evt.en = 0;
422     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC, 0);
423     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER, 0);
424 }
425 
426 static uint64_t acpi_pm_evt_read(void *opaque, hwaddr addr, unsigned width)
427 {
428     ACPIREGS *ar = opaque;
429     switch (addr) {
430     case 0:
431         return acpi_pm1_evt_get_sts(ar);
432     case 2:
433         return ar->pm1.evt.en;
434     default:
435         return 0;
436     }
437 }
438 
439 static void acpi_pm_evt_write(void *opaque, hwaddr addr, uint64_t val,
440                               unsigned width)
441 {
442     ACPIREGS *ar = opaque;
443     switch (addr) {
444     case 0:
445         acpi_pm1_evt_write_sts(ar, val);
446         ar->pm1.evt.update_sci(ar);
447         break;
448     case 2:
449         acpi_pm1_evt_write_en(ar, val);
450         ar->pm1.evt.update_sci(ar);
451         break;
452     }
453 }
454 
455 static const MemoryRegionOps acpi_pm_evt_ops = {
456     .read = acpi_pm_evt_read,
457     .write = acpi_pm_evt_write,
458     .valid.min_access_size = 2,
459     .valid.max_access_size = 2,
460     .endianness = DEVICE_LITTLE_ENDIAN,
461 };
462 
463 void acpi_pm1_evt_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
464                        MemoryRegion *parent)
465 {
466     ar->pm1.evt.update_sci = update_sci;
467     memory_region_init_io(&ar->pm1.evt.io, memory_region_owner(parent),
468                           &acpi_pm_evt_ops, ar, "acpi-evt", 4);
469     memory_region_add_subregion(parent, 0, &ar->pm1.evt.io);
470 }
471 
472 /* ACPI PM_TMR */
473 void acpi_pm_tmr_update(ACPIREGS *ar, bool enable)
474 {
475     int64_t expire_time;
476 
477     /* schedule a timer interruption if needed */
478     if (enable) {
479         expire_time = muldiv64(ar->tmr.overflow_time, get_ticks_per_sec(),
480                                PM_TIMER_FREQUENCY);
481         timer_mod(ar->tmr.timer, expire_time);
482     } else {
483         timer_del(ar->tmr.timer);
484     }
485 }
486 
487 void acpi_pm_tmr_calc_overflow_time(ACPIREGS *ar)
488 {
489     int64_t d = acpi_pm_tmr_get_clock();
490     ar->tmr.overflow_time = (d + 0x800000LL) & ~0x7fffffLL;
491 }
492 
493 static uint32_t acpi_pm_tmr_get(ACPIREGS *ar)
494 {
495     uint32_t d = acpi_pm_tmr_get_clock();
496     return d & 0xffffff;
497 }
498 
499 static void acpi_pm_tmr_timer(void *opaque)
500 {
501     ACPIREGS *ar = opaque;
502     qemu_system_wakeup_request(QEMU_WAKEUP_REASON_PMTIMER);
503     ar->tmr.update_sci(ar);
504 }
505 
506 static uint64_t acpi_pm_tmr_read(void *opaque, hwaddr addr, unsigned width)
507 {
508     return acpi_pm_tmr_get(opaque);
509 }
510 
511 static void acpi_pm_tmr_write(void *opaque, hwaddr addr, uint64_t val,
512                               unsigned width)
513 {
514     /* nothing */
515 }
516 
517 static const MemoryRegionOps acpi_pm_tmr_ops = {
518     .read = acpi_pm_tmr_read,
519     .write = acpi_pm_tmr_write,
520     .valid.min_access_size = 4,
521     .valid.max_access_size = 4,
522     .endianness = DEVICE_LITTLE_ENDIAN,
523 };
524 
525 void acpi_pm_tmr_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
526                       MemoryRegion *parent)
527 {
528     ar->tmr.update_sci = update_sci;
529     ar->tmr.timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, acpi_pm_tmr_timer, ar);
530     memory_region_init_io(&ar->tmr.io, memory_region_owner(parent),
531                           &acpi_pm_tmr_ops, ar, "acpi-tmr", 4);
532     memory_region_clear_global_locking(&ar->tmr.io);
533     memory_region_add_subregion(parent, 8, &ar->tmr.io);
534 }
535 
536 void acpi_pm_tmr_reset(ACPIREGS *ar)
537 {
538     ar->tmr.overflow_time = 0;
539     timer_del(ar->tmr.timer);
540 }
541 
542 /* ACPI PM1aCNT */
543 static void acpi_pm1_cnt_write(ACPIREGS *ar, uint16_t val)
544 {
545     ar->pm1.cnt.cnt = val & ~(ACPI_BITMASK_SLEEP_ENABLE);
546 
547     if (val & ACPI_BITMASK_SLEEP_ENABLE) {
548         /* change suspend type */
549         uint16_t sus_typ = (val >> 10) & 7;
550         switch(sus_typ) {
551         case 0: /* soft power off */
552             qemu_system_shutdown_request();
553             break;
554         case 1:
555             qemu_system_suspend_request();
556             break;
557         default:
558             if (sus_typ == ar->pm1.cnt.s4_val) { /* S4 request */
559                 qapi_event_send_suspend_disk(&error_abort);
560                 qemu_system_shutdown_request();
561             }
562             break;
563         }
564     }
565 }
566 
567 void acpi_pm1_cnt_update(ACPIREGS *ar,
568                          bool sci_enable, bool sci_disable)
569 {
570     /* ACPI specs 3.0, 4.7.2.5 */
571     if (sci_enable) {
572         ar->pm1.cnt.cnt |= ACPI_BITMASK_SCI_ENABLE;
573     } else if (sci_disable) {
574         ar->pm1.cnt.cnt &= ~ACPI_BITMASK_SCI_ENABLE;
575     }
576 }
577 
578 static uint64_t acpi_pm_cnt_read(void *opaque, hwaddr addr, unsigned width)
579 {
580     ACPIREGS *ar = opaque;
581     return ar->pm1.cnt.cnt;
582 }
583 
584 static void acpi_pm_cnt_write(void *opaque, hwaddr addr, uint64_t val,
585                               unsigned width)
586 {
587     acpi_pm1_cnt_write(opaque, val);
588 }
589 
590 static const MemoryRegionOps acpi_pm_cnt_ops = {
591     .read = acpi_pm_cnt_read,
592     .write = acpi_pm_cnt_write,
593     .valid.min_access_size = 2,
594     .valid.max_access_size = 2,
595     .endianness = DEVICE_LITTLE_ENDIAN,
596 };
597 
598 void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent,
599                        bool disable_s3, bool disable_s4, uint8_t s4_val)
600 {
601     FWCfgState *fw_cfg;
602 
603     ar->pm1.cnt.s4_val = s4_val;
604     ar->wakeup.notify = acpi_notify_wakeup;
605     qemu_register_wakeup_notifier(&ar->wakeup);
606     memory_region_init_io(&ar->pm1.cnt.io, memory_region_owner(parent),
607                           &acpi_pm_cnt_ops, ar, "acpi-cnt", 2);
608     memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io);
609 
610     fw_cfg = fw_cfg_find();
611     if (fw_cfg) {
612         uint8_t suspend[6] = {128, 0, 0, 129, 128, 128};
613         suspend[3] = 1 | ((!disable_s3) << 7);
614         suspend[4] = s4_val | ((!disable_s4) << 7);
615 
616         fw_cfg_add_file(fw_cfg, "etc/system-states", g_memdup(suspend, 6), 6);
617     }
618 }
619 
620 void acpi_pm1_cnt_reset(ACPIREGS *ar)
621 {
622     ar->pm1.cnt.cnt = 0;
623 }
624 
625 /* ACPI GPE */
626 void acpi_gpe_init(ACPIREGS *ar, uint8_t len)
627 {
628     ar->gpe.len = len;
629     /* Only first len / 2 bytes are ever used,
630      * but the caller in ich9.c migrates full len bytes.
631      * TODO: fix ich9.c and drop the extra allocation.
632      */
633     ar->gpe.sts = g_malloc0(len);
634     ar->gpe.en = g_malloc0(len);
635 }
636 
637 void acpi_gpe_reset(ACPIREGS *ar)
638 {
639     memset(ar->gpe.sts, 0, ar->gpe.len / 2);
640     memset(ar->gpe.en, 0, ar->gpe.len / 2);
641 }
642 
643 static uint8_t *acpi_gpe_ioport_get_ptr(ACPIREGS *ar, uint32_t addr)
644 {
645     uint8_t *cur = NULL;
646 
647     if (addr < ar->gpe.len / 2) {
648         cur = ar->gpe.sts + addr;
649     } else if (addr < ar->gpe.len) {
650         cur = ar->gpe.en + addr - ar->gpe.len / 2;
651     } else {
652         abort();
653     }
654 
655     return cur;
656 }
657 
658 void acpi_gpe_ioport_writeb(ACPIREGS *ar, uint32_t addr, uint32_t val)
659 {
660     uint8_t *cur;
661 
662     cur = acpi_gpe_ioport_get_ptr(ar, addr);
663     if (addr < ar->gpe.len / 2) {
664         /* GPE_STS */
665         *cur = (*cur) & ~val;
666     } else if (addr < ar->gpe.len) {
667         /* GPE_EN */
668         *cur = val;
669     } else {
670         abort();
671     }
672 }
673 
674 uint32_t acpi_gpe_ioport_readb(ACPIREGS *ar, uint32_t addr)
675 {
676     uint8_t *cur;
677     uint32_t val;
678 
679     cur = acpi_gpe_ioport_get_ptr(ar, addr);
680     val = 0;
681     if (cur != NULL) {
682         val = *cur;
683     }
684 
685     return val;
686 }
687 
688 void acpi_send_gpe_event(ACPIREGS *ar, qemu_irq irq,
689                          AcpiGPEStatusBits status)
690 {
691     ar->gpe.sts[0] |= status;
692     acpi_update_sci(ar, irq);
693 }
694 
695 void acpi_update_sci(ACPIREGS *regs, qemu_irq irq)
696 {
697     int sci_level, pm1a_sts;
698 
699     pm1a_sts = acpi_pm1_evt_get_sts(regs);
700 
701     sci_level = ((pm1a_sts &
702                   regs->pm1.evt.en & ACPI_BITMASK_PM1_COMMON_ENABLED) != 0) ||
703                 ((regs->gpe.sts[0] & regs->gpe.en[0]) != 0);
704 
705     qemu_set_irq(irq, sci_level);
706 
707     /* schedule a timer interruption if needed */
708     acpi_pm_tmr_update(regs,
709                        (regs->pm1.evt.en & ACPI_BITMASK_TIMER_ENABLE) &&
710                        !(pm1a_sts & ACPI_BITMASK_TIMER_STATUS));
711 }
712