xref: /openbmc/qemu/hw/acpi/core.c (revision fa59483d)
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 
22 #include "qemu/osdep.h"
23 #include "sysemu/sysemu.h"
24 #include "hw/hw.h"
25 #include "hw/acpi/acpi.h"
26 #include "hw/nvram/fw_cfg.h"
27 #include "qemu/config-file.h"
28 #include "qapi/error.h"
29 #include "qapi/opts-visitor.h"
30 #include "qapi/qapi-events-run-state.h"
31 #include "qapi/qapi-visit-misc.h"
32 #include "qemu/error-report.h"
33 #include "qemu/option.h"
34 
35 struct acpi_table_header {
36     uint16_t _length;         /* our length, not actual part of the hdr */
37                               /* allows easier parsing for fw_cfg clients */
38     char sig[4]
39              QEMU_NONSTRING;  /* ACPI signature (4 ASCII characters) */
40     uint32_t length;          /* Length of table, in bytes, including header */
41     uint8_t revision;         /* ACPI Specification minor version # */
42     uint8_t checksum;         /* To make sum of entire table == 0 */
43     char oem_id[6]
44              QEMU_NONSTRING;  /* OEM identification */
45     char oem_table_id[8]
46              QEMU_NONSTRING;  /* OEM table identification */
47     uint32_t oem_revision;    /* OEM revision number */
48     char asl_compiler_id[4]
49              QEMU_NONSTRING;  /* ASL compiler vendor ID */
50     uint32_t asl_compiler_revision; /* ASL compiler revision number */
51 } QEMU_PACKED;
52 
53 #define ACPI_TABLE_HDR_SIZE sizeof(struct acpi_table_header)
54 #define ACPI_TABLE_PFX_SIZE sizeof(uint16_t)  /* size of the extra prefix */
55 
56 static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE - ACPI_TABLE_PFX_SIZE] =
57     "QEMU\0\0\0\0\1\0"       /* sig (4), len(4), revno (1), csum (1) */
58     "QEMUQEQEMUQEMU\1\0\0\0" /* OEM id (6), table (8), revno (4) */
59     "QEMU\1\0\0\0"           /* ASL compiler ID (4), version (4) */
60     ;
61 
62 char unsigned *acpi_tables;
63 size_t acpi_tables_len;
64 
65 static QemuOptsList qemu_acpi_opts = {
66     .name = "acpi",
67     .implied_opt_name = "data",
68     .head = QTAILQ_HEAD_INITIALIZER(qemu_acpi_opts.head),
69     .desc = { { 0 } } /* validated with OptsVisitor */
70 };
71 
72 static void acpi_register_config(void)
73 {
74     qemu_add_opts(&qemu_acpi_opts);
75 }
76 
77 opts_init(acpi_register_config);
78 
79 static int acpi_checksum(const uint8_t *data, int len)
80 {
81     int sum, i;
82     sum = 0;
83     for (i = 0; i < len; i++) {
84         sum += data[i];
85     }
86     return (-sum) & 0xff;
87 }
88 
89 
90 /* Install a copy of the ACPI table specified in @blob.
91  *
92  * If @has_header is set, @blob starts with the System Description Table Header
93  * structure. Otherwise, "dfl_hdr" is prepended. In any case, each header field
94  * is optionally overwritten from @hdrs.
95  *
96  * It is valid to call this function with
97  * (@blob == NULL && bloblen == 0 && !has_header).
98  *
99  * @hdrs->file and @hdrs->data are ignored.
100  *
101  * SIZE_MAX is considered "infinity" in this function.
102  *
103  * The number of tables that can be installed is not limited, but the 16-bit
104  * counter at the beginning of "acpi_tables" wraps around after UINT16_MAX.
105  */
106 static void acpi_table_install(const char unsigned *blob, size_t bloblen,
107                                bool has_header,
108                                const struct AcpiTableOptions *hdrs,
109                                Error **errp)
110 {
111     size_t body_start;
112     const char unsigned *hdr_src;
113     size_t body_size, acpi_payload_size;
114     struct acpi_table_header *ext_hdr;
115     unsigned changed_fields;
116 
117     /* Calculate where the ACPI table body starts within the blob, plus where
118      * to copy the ACPI table header from.
119      */
120     if (has_header) {
121         /*   _length             | ACPI header in blob | blob body
122          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^
123          *   ACPI_TABLE_PFX_SIZE     sizeof dfl_hdr      body_size
124          *                           == body_start
125          *
126          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
127          *                           acpi_payload_size == bloblen
128          */
129         body_start = sizeof dfl_hdr;
130 
131         if (bloblen < body_start) {
132             error_setg(errp, "ACPI table claiming to have header is too "
133                        "short, available: %zu, expected: %zu", bloblen,
134                        body_start);
135             return;
136         }
137         hdr_src = blob;
138     } else {
139         /*   _length             | ACPI header in template | blob body
140          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^
141          *   ACPI_TABLE_PFX_SIZE       sizeof dfl_hdr        body_size
142          *                                                   == bloblen
143          *
144          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
145          *                                  acpi_payload_size
146          */
147         body_start = 0;
148         hdr_src = dfl_hdr;
149     }
150     body_size = bloblen - body_start;
151     acpi_payload_size = sizeof dfl_hdr + body_size;
152 
153     if (acpi_payload_size > UINT16_MAX) {
154         error_setg(errp, "ACPI table too big, requested: %zu, max: %u",
155                    acpi_payload_size, (unsigned)UINT16_MAX);
156         return;
157     }
158 
159     /* We won't fail from here on. Initialize / extend the globals. */
160     if (acpi_tables == NULL) {
161         acpi_tables_len = sizeof(uint16_t);
162         acpi_tables = g_malloc0(acpi_tables_len);
163     }
164 
165     acpi_tables = g_realloc(acpi_tables, acpi_tables_len +
166                                          ACPI_TABLE_PFX_SIZE +
167                                          sizeof dfl_hdr + body_size);
168 
169     ext_hdr = (struct acpi_table_header *)(acpi_tables + acpi_tables_len);
170     acpi_tables_len += ACPI_TABLE_PFX_SIZE;
171 
172     memcpy(acpi_tables + acpi_tables_len, hdr_src, sizeof dfl_hdr);
173     acpi_tables_len += sizeof dfl_hdr;
174 
175     if (blob != NULL) {
176         memcpy(acpi_tables + acpi_tables_len, blob + body_start, body_size);
177         acpi_tables_len += body_size;
178     }
179 
180     /* increase number of tables */
181     stw_le_p(acpi_tables, lduw_le_p(acpi_tables) + 1u);
182 
183     /* Update the header fields. The strings need not be NUL-terminated. */
184     changed_fields = 0;
185     ext_hdr->_length = cpu_to_le16(acpi_payload_size);
186 
187     if (hdrs->has_sig) {
188         strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig);
189         ++changed_fields;
190     }
191 
192     if (has_header && le32_to_cpu(ext_hdr->length) != acpi_payload_size) {
193         warn_report("ACPI table has wrong length, header says "
194                     "%" PRIu32 ", actual size %zu bytes",
195                     le32_to_cpu(ext_hdr->length), acpi_payload_size);
196     }
197     ext_hdr->length = cpu_to_le32(acpi_payload_size);
198 
199     if (hdrs->has_rev) {
200         ext_hdr->revision = hdrs->rev;
201         ++changed_fields;
202     }
203 
204     ext_hdr->checksum = 0;
205 
206     if (hdrs->has_oem_id) {
207         strncpy(ext_hdr->oem_id, hdrs->oem_id, sizeof ext_hdr->oem_id);
208         ++changed_fields;
209     }
210     if (hdrs->has_oem_table_id) {
211         strncpy(ext_hdr->oem_table_id, hdrs->oem_table_id,
212                 sizeof ext_hdr->oem_table_id);
213         ++changed_fields;
214     }
215     if (hdrs->has_oem_rev) {
216         ext_hdr->oem_revision = cpu_to_le32(hdrs->oem_rev);
217         ++changed_fields;
218     }
219     if (hdrs->has_asl_compiler_id) {
220         strncpy(ext_hdr->asl_compiler_id, hdrs->asl_compiler_id,
221                 sizeof ext_hdr->asl_compiler_id);
222         ++changed_fields;
223     }
224     if (hdrs->has_asl_compiler_rev) {
225         ext_hdr->asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev);
226         ++changed_fields;
227     }
228 
229     if (!has_header && changed_fields == 0) {
230         warn_report("ACPI table: no headers are specified");
231     }
232 
233     /* recalculate checksum */
234     ext_hdr->checksum = acpi_checksum((const char unsigned *)ext_hdr +
235                                       ACPI_TABLE_PFX_SIZE, acpi_payload_size);
236 }
237 
238 void acpi_table_add(const QemuOpts *opts, Error **errp)
239 {
240     AcpiTableOptions *hdrs = NULL;
241     Error *err = NULL;
242     char **pathnames = NULL;
243     char **cur;
244     size_t bloblen = 0;
245     char unsigned *blob = NULL;
246 
247     {
248         Visitor *v;
249 
250         v = opts_visitor_new(opts);
251         visit_type_AcpiTableOptions(v, NULL, &hdrs, &err);
252         visit_free(v);
253     }
254 
255     if (err) {
256         goto out;
257     }
258     if (hdrs->has_file == hdrs->has_data) {
259         error_setg(&err, "'-acpitable' requires one of 'data' or 'file'");
260         goto out;
261     }
262 
263     pathnames = g_strsplit(hdrs->has_file ? hdrs->file : hdrs->data, ":", 0);
264     if (pathnames == NULL || pathnames[0] == NULL) {
265         error_setg(&err, "'-acpitable' requires at least one pathname");
266         goto out;
267     }
268 
269     /* now read in the data files, reallocating buffer as needed */
270     for (cur = pathnames; *cur; ++cur) {
271         int fd = open(*cur, O_RDONLY | O_BINARY);
272 
273         if (fd < 0) {
274             error_setg(&err, "can't open file %s: %s", *cur, strerror(errno));
275             goto out;
276         }
277 
278         for (;;) {
279             char unsigned data[8192];
280             ssize_t r;
281 
282             r = read(fd, data, sizeof data);
283             if (r == 0) {
284                 break;
285             } else if (r > 0) {
286                 blob = g_realloc(blob, bloblen + r);
287                 memcpy(blob + bloblen, data, r);
288                 bloblen += r;
289             } else if (errno != EINTR) {
290                 error_setg(&err, "can't read file %s: %s",
291                            *cur, strerror(errno));
292                 close(fd);
293                 goto out;
294             }
295         }
296 
297         close(fd);
298     }
299 
300     acpi_table_install(blob, bloblen, hdrs->has_file, hdrs, &err);
301 
302 out:
303     g_free(blob);
304     g_strfreev(pathnames);
305     qapi_free_AcpiTableOptions(hdrs);
306 
307     error_propagate(errp, err);
308 }
309 
310 unsigned acpi_table_len(void *current)
311 {
312     struct acpi_table_header *hdr = current - sizeof(hdr->_length);
313     return hdr->_length;
314 }
315 
316 static
317 void *acpi_table_hdr(void *h)
318 {
319     struct acpi_table_header *hdr = h;
320     return &hdr->sig;
321 }
322 
323 uint8_t *acpi_table_first(void)
324 {
325     if (!acpi_tables) {
326         return NULL;
327     }
328     return acpi_table_hdr(acpi_tables + ACPI_TABLE_PFX_SIZE);
329 }
330 
331 uint8_t *acpi_table_next(uint8_t *current)
332 {
333     uint8_t *next = current + acpi_table_len(current);
334 
335     if (next - acpi_tables >= acpi_tables_len) {
336         return NULL;
337     } else {
338         return acpi_table_hdr(next);
339     }
340 }
341 
342 int acpi_get_slic_oem(AcpiSlicOem *oem)
343 {
344     uint8_t *u;
345 
346     for (u = acpi_table_first(); u; u = acpi_table_next(u)) {
347         struct acpi_table_header *hdr = (void *)(u - sizeof(hdr->_length));
348 
349         if (memcmp(hdr->sig, "SLIC", 4) == 0) {
350             oem->id = hdr->oem_id;
351             oem->table_id = hdr->oem_table_id;
352             return 0;
353         }
354     }
355     return -1;
356 }
357 
358 static void acpi_notify_wakeup(Notifier *notifier, void *data)
359 {
360     ACPIREGS *ar = container_of(notifier, ACPIREGS, wakeup);
361     WakeupReason *reason = data;
362 
363     switch (*reason) {
364     case QEMU_WAKEUP_REASON_RTC:
365         ar->pm1.evt.sts |=
366             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_RT_CLOCK_STATUS);
367         break;
368     case QEMU_WAKEUP_REASON_PMTIMER:
369         ar->pm1.evt.sts |=
370             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_TIMER_STATUS);
371         break;
372     case QEMU_WAKEUP_REASON_OTHER:
373         /* ACPI_BITMASK_WAKE_STATUS should be set on resume.
374            Pretend that resume was caused by power button */
375         ar->pm1.evt.sts |=
376             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_POWER_BUTTON_STATUS);
377         break;
378     default:
379         break;
380     }
381 }
382 
383 /* ACPI PM1a EVT */
384 uint16_t acpi_pm1_evt_get_sts(ACPIREGS *ar)
385 {
386     /* Compare ns-clock, not PM timer ticks, because
387        acpi_pm_tmr_update function uses ns for setting the timer. */
388     int64_t d = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
389     if (d >= muldiv64(ar->tmr.overflow_time,
390                       NANOSECONDS_PER_SECOND, PM_TIMER_FREQUENCY)) {
391         ar->pm1.evt.sts |= ACPI_BITMASK_TIMER_STATUS;
392     }
393     return ar->pm1.evt.sts;
394 }
395 
396 static void acpi_pm1_evt_write_sts(ACPIREGS *ar, uint16_t val)
397 {
398     uint16_t pm1_sts = acpi_pm1_evt_get_sts(ar);
399     if (pm1_sts & val & ACPI_BITMASK_TIMER_STATUS) {
400         /* if TMRSTS is reset, then compute the new overflow time */
401         acpi_pm_tmr_calc_overflow_time(ar);
402     }
403     ar->pm1.evt.sts &= ~val;
404 }
405 
406 static void acpi_pm1_evt_write_en(ACPIREGS *ar, uint16_t val)
407 {
408     ar->pm1.evt.en = val;
409     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC,
410                               val & ACPI_BITMASK_RT_CLOCK_ENABLE);
411     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER,
412                               val & ACPI_BITMASK_TIMER_ENABLE);
413 }
414 
415 void acpi_pm1_evt_power_down(ACPIREGS *ar)
416 {
417     if (ar->pm1.evt.en & ACPI_BITMASK_POWER_BUTTON_ENABLE) {
418         ar->pm1.evt.sts |= ACPI_BITMASK_POWER_BUTTON_STATUS;
419         ar->tmr.update_sci(ar);
420     }
421 }
422 
423 void acpi_pm1_evt_reset(ACPIREGS *ar)
424 {
425     ar->pm1.evt.sts = 0;
426     ar->pm1.evt.en = 0;
427     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC, 0);
428     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER, 0);
429 }
430 
431 static uint64_t acpi_pm_evt_read(void *opaque, hwaddr addr, unsigned width)
432 {
433     ACPIREGS *ar = opaque;
434     switch (addr) {
435     case 0:
436         return acpi_pm1_evt_get_sts(ar);
437     case 2:
438         return ar->pm1.evt.en;
439     default:
440         return 0;
441     }
442 }
443 
444 static void acpi_pm_evt_write(void *opaque, hwaddr addr, uint64_t val,
445                               unsigned width)
446 {
447     ACPIREGS *ar = opaque;
448     switch (addr) {
449     case 0:
450         acpi_pm1_evt_write_sts(ar, val);
451         ar->pm1.evt.update_sci(ar);
452         break;
453     case 2:
454         acpi_pm1_evt_write_en(ar, val);
455         ar->pm1.evt.update_sci(ar);
456         break;
457     }
458 }
459 
460 static const MemoryRegionOps acpi_pm_evt_ops = {
461     .read = acpi_pm_evt_read,
462     .write = acpi_pm_evt_write,
463     .valid.min_access_size = 2,
464     .valid.max_access_size = 2,
465     .endianness = DEVICE_LITTLE_ENDIAN,
466 };
467 
468 void acpi_pm1_evt_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
469                        MemoryRegion *parent)
470 {
471     ar->pm1.evt.update_sci = update_sci;
472     memory_region_init_io(&ar->pm1.evt.io, memory_region_owner(parent),
473                           &acpi_pm_evt_ops, ar, "acpi-evt", 4);
474     memory_region_add_subregion(parent, 0, &ar->pm1.evt.io);
475 }
476 
477 /* ACPI PM_TMR */
478 void acpi_pm_tmr_update(ACPIREGS *ar, bool enable)
479 {
480     int64_t expire_time;
481 
482     /* schedule a timer interruption if needed */
483     if (enable) {
484         expire_time = muldiv64(ar->tmr.overflow_time, NANOSECONDS_PER_SECOND,
485                                PM_TIMER_FREQUENCY);
486         timer_mod(ar->tmr.timer, expire_time);
487     } else {
488         timer_del(ar->tmr.timer);
489     }
490 }
491 
492 static inline int64_t acpi_pm_tmr_get_clock(void)
493 {
494     return muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL), PM_TIMER_FREQUENCY,
495                     NANOSECONDS_PER_SECOND);
496 }
497 
498 void acpi_pm_tmr_calc_overflow_time(ACPIREGS *ar)
499 {
500     int64_t d = acpi_pm_tmr_get_clock();
501     ar->tmr.overflow_time = (d + 0x800000LL) & ~0x7fffffLL;
502 }
503 
504 static uint32_t acpi_pm_tmr_get(ACPIREGS *ar)
505 {
506     uint32_t d = acpi_pm_tmr_get_clock();
507     return d & 0xffffff;
508 }
509 
510 static void acpi_pm_tmr_timer(void *opaque)
511 {
512     ACPIREGS *ar = opaque;
513 
514     qemu_system_wakeup_request(QEMU_WAKEUP_REASON_PMTIMER, NULL);
515     ar->tmr.update_sci(ar);
516 }
517 
518 static uint64_t acpi_pm_tmr_read(void *opaque, hwaddr addr, unsigned width)
519 {
520     return acpi_pm_tmr_get(opaque);
521 }
522 
523 static void acpi_pm_tmr_write(void *opaque, hwaddr addr, uint64_t val,
524                               unsigned width)
525 {
526     /* nothing */
527 }
528 
529 static const MemoryRegionOps acpi_pm_tmr_ops = {
530     .read = acpi_pm_tmr_read,
531     .write = acpi_pm_tmr_write,
532     .valid.min_access_size = 4,
533     .valid.max_access_size = 4,
534     .endianness = DEVICE_LITTLE_ENDIAN,
535 };
536 
537 void acpi_pm_tmr_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
538                       MemoryRegion *parent)
539 {
540     ar->tmr.update_sci = update_sci;
541     ar->tmr.timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, acpi_pm_tmr_timer, ar);
542     memory_region_init_io(&ar->tmr.io, memory_region_owner(parent),
543                           &acpi_pm_tmr_ops, ar, "acpi-tmr", 4);
544     memory_region_add_subregion(parent, 8, &ar->tmr.io);
545 }
546 
547 void acpi_pm_tmr_reset(ACPIREGS *ar)
548 {
549     ar->tmr.overflow_time = 0;
550     timer_del(ar->tmr.timer);
551 }
552 
553 /* ACPI PM1aCNT */
554 static void acpi_pm1_cnt_write(ACPIREGS *ar, uint16_t val)
555 {
556     ar->pm1.cnt.cnt = val & ~(ACPI_BITMASK_SLEEP_ENABLE);
557 
558     if (val & ACPI_BITMASK_SLEEP_ENABLE) {
559         /* change suspend type */
560         uint16_t sus_typ = (val >> 10) & 7;
561         switch(sus_typ) {
562         case 0: /* soft power off */
563             qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
564             break;
565         case 1:
566             qemu_system_suspend_request();
567             break;
568         default:
569             if (sus_typ == ar->pm1.cnt.s4_val) { /* S4 request */
570                 qapi_event_send_suspend_disk();
571                 qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
572             }
573             break;
574         }
575     }
576 }
577 
578 void acpi_pm1_cnt_update(ACPIREGS *ar,
579                          bool sci_enable, bool sci_disable)
580 {
581     /* ACPI specs 3.0, 4.7.2.5 */
582     if (sci_enable) {
583         ar->pm1.cnt.cnt |= ACPI_BITMASK_SCI_ENABLE;
584     } else if (sci_disable) {
585         ar->pm1.cnt.cnt &= ~ACPI_BITMASK_SCI_ENABLE;
586     }
587 }
588 
589 static uint64_t acpi_pm_cnt_read(void *opaque, hwaddr addr, unsigned width)
590 {
591     ACPIREGS *ar = opaque;
592     return ar->pm1.cnt.cnt;
593 }
594 
595 static void acpi_pm_cnt_write(void *opaque, hwaddr addr, uint64_t val,
596                               unsigned width)
597 {
598     acpi_pm1_cnt_write(opaque, val);
599 }
600 
601 static const MemoryRegionOps acpi_pm_cnt_ops = {
602     .read = acpi_pm_cnt_read,
603     .write = acpi_pm_cnt_write,
604     .valid.min_access_size = 2,
605     .valid.max_access_size = 2,
606     .endianness = DEVICE_LITTLE_ENDIAN,
607 };
608 
609 void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent,
610                        bool disable_s3, bool disable_s4, uint8_t s4_val)
611 {
612     FWCfgState *fw_cfg;
613 
614     ar->pm1.cnt.s4_val = s4_val;
615     ar->wakeup.notify = acpi_notify_wakeup;
616     qemu_register_wakeup_notifier(&ar->wakeup);
617 
618     /*
619      * Register wake-up support in QMP query-current-machine API
620      */
621     qemu_register_wakeup_support();
622 
623     memory_region_init_io(&ar->pm1.cnt.io, memory_region_owner(parent),
624                           &acpi_pm_cnt_ops, ar, "acpi-cnt", 2);
625     memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io);
626 
627     fw_cfg = fw_cfg_find();
628     if (fw_cfg) {
629         uint8_t suspend[6] = {128, 0, 0, 129, 128, 128};
630         suspend[3] = 1 | ((!disable_s3) << 7);
631         suspend[4] = s4_val | ((!disable_s4) << 7);
632 
633         fw_cfg_add_file(fw_cfg, "etc/system-states", g_memdup(suspend, 6), 6);
634     }
635 }
636 
637 void acpi_pm1_cnt_reset(ACPIREGS *ar)
638 {
639     ar->pm1.cnt.cnt = 0;
640 }
641 
642 /* ACPI GPE */
643 void acpi_gpe_init(ACPIREGS *ar, uint8_t len)
644 {
645     ar->gpe.len = len;
646     /* Only first len / 2 bytes are ever used,
647      * but the caller in ich9.c migrates full len bytes.
648      * TODO: fix ich9.c and drop the extra allocation.
649      */
650     ar->gpe.sts = g_malloc0(len);
651     ar->gpe.en = g_malloc0(len);
652 }
653 
654 void acpi_gpe_reset(ACPIREGS *ar)
655 {
656     memset(ar->gpe.sts, 0, ar->gpe.len / 2);
657     memset(ar->gpe.en, 0, ar->gpe.len / 2);
658 }
659 
660 static uint8_t *acpi_gpe_ioport_get_ptr(ACPIREGS *ar, uint32_t addr)
661 {
662     uint8_t *cur = NULL;
663 
664     if (addr < ar->gpe.len / 2) {
665         cur = ar->gpe.sts + addr;
666     } else if (addr < ar->gpe.len) {
667         cur = ar->gpe.en + addr - ar->gpe.len / 2;
668     } else {
669         abort();
670     }
671 
672     return cur;
673 }
674 
675 void acpi_gpe_ioport_writeb(ACPIREGS *ar, uint32_t addr, uint32_t val)
676 {
677     uint8_t *cur;
678 
679     cur = acpi_gpe_ioport_get_ptr(ar, addr);
680     if (addr < ar->gpe.len / 2) {
681         /* GPE_STS */
682         *cur = (*cur) & ~val;
683     } else if (addr < ar->gpe.len) {
684         /* GPE_EN */
685         *cur = val;
686     } else {
687         abort();
688     }
689 }
690 
691 uint32_t acpi_gpe_ioport_readb(ACPIREGS *ar, uint32_t addr)
692 {
693     uint8_t *cur;
694     uint32_t val;
695 
696     cur = acpi_gpe_ioport_get_ptr(ar, addr);
697     val = 0;
698     if (cur != NULL) {
699         val = *cur;
700     }
701 
702     return val;
703 }
704 
705 void acpi_send_gpe_event(ACPIREGS *ar, qemu_irq irq,
706                          AcpiEventStatusBits status)
707 {
708     ar->gpe.sts[0] |= status;
709     acpi_update_sci(ar, irq);
710 }
711 
712 void acpi_update_sci(ACPIREGS *regs, qemu_irq irq)
713 {
714     int sci_level, pm1a_sts;
715 
716     pm1a_sts = acpi_pm1_evt_get_sts(regs);
717 
718     sci_level = ((pm1a_sts &
719                   regs->pm1.evt.en & ACPI_BITMASK_PM1_COMMON_ENABLED) != 0) ||
720                 ((regs->gpe.sts[0] & regs->gpe.en[0]) != 0);
721 
722     qemu_set_irq(irq, sci_level);
723 
724     /* schedule a timer interruption if needed */
725     acpi_pm_tmr_update(regs,
726                        (regs->pm1.evt.en & ACPI_BITMASK_TIMER_ENABLE) &&
727                        !(pm1a_sts & ACPI_BITMASK_TIMER_STATUS));
728 }
729