xref: /openbmc/qemu/hw/acpi/core.c (revision 500eb6db)
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/module.h"
34 #include "qemu/option.h"
35 
36 struct acpi_table_header {
37     uint16_t _length;         /* our length, not actual part of the hdr */
38                               /* allows easier parsing for fw_cfg clients */
39     char sig[4]
40              QEMU_NONSTRING;  /* ACPI signature (4 ASCII characters) */
41     uint32_t length;          /* Length of table, in bytes, including header */
42     uint8_t revision;         /* ACPI Specification minor version # */
43     uint8_t checksum;         /* To make sum of entire table == 0 */
44     char oem_id[6]
45              QEMU_NONSTRING;  /* OEM identification */
46     char oem_table_id[8]
47              QEMU_NONSTRING;  /* OEM table identification */
48     uint32_t oem_revision;    /* OEM revision number */
49     char asl_compiler_id[4]
50              QEMU_NONSTRING;  /* ASL compiler vendor ID */
51     uint32_t asl_compiler_revision; /* ASL compiler revision number */
52 } QEMU_PACKED;
53 
54 #define ACPI_TABLE_HDR_SIZE sizeof(struct acpi_table_header)
55 #define ACPI_TABLE_PFX_SIZE sizeof(uint16_t)  /* size of the extra prefix */
56 
57 static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE - ACPI_TABLE_PFX_SIZE] =
58     "QEMU\0\0\0\0\1\0"       /* sig (4), len(4), revno (1), csum (1) */
59     "QEMUQEQEMUQEMU\1\0\0\0" /* OEM id (6), table (8), revno (4) */
60     "QEMU\1\0\0\0"           /* ASL compiler ID (4), version (4) */
61     ;
62 
63 char unsigned *acpi_tables;
64 size_t acpi_tables_len;
65 
66 static QemuOptsList qemu_acpi_opts = {
67     .name = "acpi",
68     .implied_opt_name = "data",
69     .head = QTAILQ_HEAD_INITIALIZER(qemu_acpi_opts.head),
70     .desc = { { 0 } } /* validated with OptsVisitor */
71 };
72 
73 static void acpi_register_config(void)
74 {
75     qemu_add_opts(&qemu_acpi_opts);
76 }
77 
78 opts_init(acpi_register_config);
79 
80 static int acpi_checksum(const uint8_t *data, int len)
81 {
82     int sum, i;
83     sum = 0;
84     for (i = 0; i < len; i++) {
85         sum += data[i];
86     }
87     return (-sum) & 0xff;
88 }
89 
90 
91 /* Install a copy of the ACPI table specified in @blob.
92  *
93  * If @has_header is set, @blob starts with the System Description Table Header
94  * structure. Otherwise, "dfl_hdr" is prepended. In any case, each header field
95  * is optionally overwritten from @hdrs.
96  *
97  * It is valid to call this function with
98  * (@blob == NULL && bloblen == 0 && !has_header).
99  *
100  * @hdrs->file and @hdrs->data are ignored.
101  *
102  * SIZE_MAX is considered "infinity" in this function.
103  *
104  * The number of tables that can be installed is not limited, but the 16-bit
105  * counter at the beginning of "acpi_tables" wraps around after UINT16_MAX.
106  */
107 static void acpi_table_install(const char unsigned *blob, size_t bloblen,
108                                bool has_header,
109                                const struct AcpiTableOptions *hdrs,
110                                Error **errp)
111 {
112     size_t body_start;
113     const char unsigned *hdr_src;
114     size_t body_size, acpi_payload_size;
115     struct acpi_table_header *ext_hdr;
116     unsigned changed_fields;
117 
118     /* Calculate where the ACPI table body starts within the blob, plus where
119      * to copy the ACPI table header from.
120      */
121     if (has_header) {
122         /*   _length             | ACPI header in blob | blob body
123          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^
124          *   ACPI_TABLE_PFX_SIZE     sizeof dfl_hdr      body_size
125          *                           == body_start
126          *
127          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
128          *                           acpi_payload_size == bloblen
129          */
130         body_start = sizeof dfl_hdr;
131 
132         if (bloblen < body_start) {
133             error_setg(errp, "ACPI table claiming to have header is too "
134                        "short, available: %zu, expected: %zu", bloblen,
135                        body_start);
136             return;
137         }
138         hdr_src = blob;
139     } else {
140         /*   _length             | ACPI header in template | blob body
141          *   ^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^
142          *   ACPI_TABLE_PFX_SIZE       sizeof dfl_hdr        body_size
143          *                                                   == bloblen
144          *
145          *                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
146          *                                  acpi_payload_size
147          */
148         body_start = 0;
149         hdr_src = dfl_hdr;
150     }
151     body_size = bloblen - body_start;
152     acpi_payload_size = sizeof dfl_hdr + body_size;
153 
154     if (acpi_payload_size > UINT16_MAX) {
155         error_setg(errp, "ACPI table too big, requested: %zu, max: %u",
156                    acpi_payload_size, (unsigned)UINT16_MAX);
157         return;
158     }
159 
160     /* We won't fail from here on. Initialize / extend the globals. */
161     if (acpi_tables == NULL) {
162         acpi_tables_len = sizeof(uint16_t);
163         acpi_tables = g_malloc0(acpi_tables_len);
164     }
165 
166     acpi_tables = g_realloc(acpi_tables, acpi_tables_len +
167                                          ACPI_TABLE_PFX_SIZE +
168                                          sizeof dfl_hdr + body_size);
169 
170     ext_hdr = (struct acpi_table_header *)(acpi_tables + acpi_tables_len);
171     acpi_tables_len += ACPI_TABLE_PFX_SIZE;
172 
173     memcpy(acpi_tables + acpi_tables_len, hdr_src, sizeof dfl_hdr);
174     acpi_tables_len += sizeof dfl_hdr;
175 
176     if (blob != NULL) {
177         memcpy(acpi_tables + acpi_tables_len, blob + body_start, body_size);
178         acpi_tables_len += body_size;
179     }
180 
181     /* increase number of tables */
182     stw_le_p(acpi_tables, lduw_le_p(acpi_tables) + 1u);
183 
184     /* Update the header fields. The strings need not be NUL-terminated. */
185     changed_fields = 0;
186     ext_hdr->_length = cpu_to_le16(acpi_payload_size);
187 
188     if (hdrs->has_sig) {
189         strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig);
190         ++changed_fields;
191     }
192 
193     if (has_header && le32_to_cpu(ext_hdr->length) != acpi_payload_size) {
194         warn_report("ACPI table has wrong length, header says "
195                     "%" PRIu32 ", actual size %zu bytes",
196                     le32_to_cpu(ext_hdr->length), acpi_payload_size);
197     }
198     ext_hdr->length = cpu_to_le32(acpi_payload_size);
199 
200     if (hdrs->has_rev) {
201         ext_hdr->revision = hdrs->rev;
202         ++changed_fields;
203     }
204 
205     ext_hdr->checksum = 0;
206 
207     if (hdrs->has_oem_id) {
208         strncpy(ext_hdr->oem_id, hdrs->oem_id, sizeof ext_hdr->oem_id);
209         ++changed_fields;
210     }
211     if (hdrs->has_oem_table_id) {
212         strncpy(ext_hdr->oem_table_id, hdrs->oem_table_id,
213                 sizeof ext_hdr->oem_table_id);
214         ++changed_fields;
215     }
216     if (hdrs->has_oem_rev) {
217         ext_hdr->oem_revision = cpu_to_le32(hdrs->oem_rev);
218         ++changed_fields;
219     }
220     if (hdrs->has_asl_compiler_id) {
221         strncpy(ext_hdr->asl_compiler_id, hdrs->asl_compiler_id,
222                 sizeof ext_hdr->asl_compiler_id);
223         ++changed_fields;
224     }
225     if (hdrs->has_asl_compiler_rev) {
226         ext_hdr->asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev);
227         ++changed_fields;
228     }
229 
230     if (!has_header && changed_fields == 0) {
231         warn_report("ACPI table: no headers are specified");
232     }
233 
234     /* recalculate checksum */
235     ext_hdr->checksum = acpi_checksum((const char unsigned *)ext_hdr +
236                                       ACPI_TABLE_PFX_SIZE, acpi_payload_size);
237 }
238 
239 void acpi_table_add(const QemuOpts *opts, Error **errp)
240 {
241     AcpiTableOptions *hdrs = NULL;
242     Error *err = NULL;
243     char **pathnames = NULL;
244     char **cur;
245     size_t bloblen = 0;
246     char unsigned *blob = NULL;
247 
248     {
249         Visitor *v;
250 
251         v = opts_visitor_new(opts);
252         visit_type_AcpiTableOptions(v, NULL, &hdrs, &err);
253         visit_free(v);
254     }
255 
256     if (err) {
257         goto out;
258     }
259     if (hdrs->has_file == hdrs->has_data) {
260         error_setg(&err, "'-acpitable' requires one of 'data' or 'file'");
261         goto out;
262     }
263 
264     pathnames = g_strsplit(hdrs->has_file ? hdrs->file : hdrs->data, ":", 0);
265     if (pathnames == NULL || pathnames[0] == NULL) {
266         error_setg(&err, "'-acpitable' requires at least one pathname");
267         goto out;
268     }
269 
270     /* now read in the data files, reallocating buffer as needed */
271     for (cur = pathnames; *cur; ++cur) {
272         int fd = open(*cur, O_RDONLY | O_BINARY);
273 
274         if (fd < 0) {
275             error_setg(&err, "can't open file %s: %s", *cur, strerror(errno));
276             goto out;
277         }
278 
279         for (;;) {
280             char unsigned data[8192];
281             ssize_t r;
282 
283             r = read(fd, data, sizeof data);
284             if (r == 0) {
285                 break;
286             } else if (r > 0) {
287                 blob = g_realloc(blob, bloblen + r);
288                 memcpy(blob + bloblen, data, r);
289                 bloblen += r;
290             } else if (errno != EINTR) {
291                 error_setg(&err, "can't read file %s: %s",
292                            *cur, strerror(errno));
293                 close(fd);
294                 goto out;
295             }
296         }
297 
298         close(fd);
299     }
300 
301     acpi_table_install(blob, bloblen, hdrs->has_file, hdrs, &err);
302 
303 out:
304     g_free(blob);
305     g_strfreev(pathnames);
306     qapi_free_AcpiTableOptions(hdrs);
307 
308     error_propagate(errp, err);
309 }
310 
311 unsigned acpi_table_len(void *current)
312 {
313     struct acpi_table_header *hdr = current - sizeof(hdr->_length);
314     return hdr->_length;
315 }
316 
317 static
318 void *acpi_table_hdr(void *h)
319 {
320     struct acpi_table_header *hdr = h;
321     return &hdr->sig;
322 }
323 
324 uint8_t *acpi_table_first(void)
325 {
326     if (!acpi_tables) {
327         return NULL;
328     }
329     return acpi_table_hdr(acpi_tables + ACPI_TABLE_PFX_SIZE);
330 }
331 
332 uint8_t *acpi_table_next(uint8_t *current)
333 {
334     uint8_t *next = current + acpi_table_len(current);
335 
336     if (next - acpi_tables >= acpi_tables_len) {
337         return NULL;
338     } else {
339         return acpi_table_hdr(next);
340     }
341 }
342 
343 int acpi_get_slic_oem(AcpiSlicOem *oem)
344 {
345     uint8_t *u;
346 
347     for (u = acpi_table_first(); u; u = acpi_table_next(u)) {
348         struct acpi_table_header *hdr = (void *)(u - sizeof(hdr->_length));
349 
350         if (memcmp(hdr->sig, "SLIC", 4) == 0) {
351             oem->id = hdr->oem_id;
352             oem->table_id = hdr->oem_table_id;
353             return 0;
354         }
355     }
356     return -1;
357 }
358 
359 static void acpi_notify_wakeup(Notifier *notifier, void *data)
360 {
361     ACPIREGS *ar = container_of(notifier, ACPIREGS, wakeup);
362     WakeupReason *reason = data;
363 
364     switch (*reason) {
365     case QEMU_WAKEUP_REASON_RTC:
366         ar->pm1.evt.sts |=
367             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_RT_CLOCK_STATUS);
368         break;
369     case QEMU_WAKEUP_REASON_PMTIMER:
370         ar->pm1.evt.sts |=
371             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_TIMER_STATUS);
372         break;
373     case QEMU_WAKEUP_REASON_OTHER:
374         /* ACPI_BITMASK_WAKE_STATUS should be set on resume.
375            Pretend that resume was caused by power button */
376         ar->pm1.evt.sts |=
377             (ACPI_BITMASK_WAKE_STATUS | ACPI_BITMASK_POWER_BUTTON_STATUS);
378         break;
379     default:
380         break;
381     }
382 }
383 
384 /* ACPI PM1a EVT */
385 uint16_t acpi_pm1_evt_get_sts(ACPIREGS *ar)
386 {
387     /* Compare ns-clock, not PM timer ticks, because
388        acpi_pm_tmr_update function uses ns for setting the timer. */
389     int64_t d = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
390     if (d >= muldiv64(ar->tmr.overflow_time,
391                       NANOSECONDS_PER_SECOND, PM_TIMER_FREQUENCY)) {
392         ar->pm1.evt.sts |= ACPI_BITMASK_TIMER_STATUS;
393     }
394     return ar->pm1.evt.sts;
395 }
396 
397 static void acpi_pm1_evt_write_sts(ACPIREGS *ar, uint16_t val)
398 {
399     uint16_t pm1_sts = acpi_pm1_evt_get_sts(ar);
400     if (pm1_sts & val & ACPI_BITMASK_TIMER_STATUS) {
401         /* if TMRSTS is reset, then compute the new overflow time */
402         acpi_pm_tmr_calc_overflow_time(ar);
403     }
404     ar->pm1.evt.sts &= ~val;
405 }
406 
407 static void acpi_pm1_evt_write_en(ACPIREGS *ar, uint16_t val)
408 {
409     ar->pm1.evt.en = val;
410     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC,
411                               val & ACPI_BITMASK_RT_CLOCK_ENABLE);
412     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER,
413                               val & ACPI_BITMASK_TIMER_ENABLE);
414 }
415 
416 void acpi_pm1_evt_power_down(ACPIREGS *ar)
417 {
418     if (ar->pm1.evt.en & ACPI_BITMASK_POWER_BUTTON_ENABLE) {
419         ar->pm1.evt.sts |= ACPI_BITMASK_POWER_BUTTON_STATUS;
420         ar->tmr.update_sci(ar);
421     }
422 }
423 
424 void acpi_pm1_evt_reset(ACPIREGS *ar)
425 {
426     ar->pm1.evt.sts = 0;
427     ar->pm1.evt.en = 0;
428     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_RTC, 0);
429     qemu_system_wakeup_enable(QEMU_WAKEUP_REASON_PMTIMER, 0);
430 }
431 
432 static uint64_t acpi_pm_evt_read(void *opaque, hwaddr addr, unsigned width)
433 {
434     ACPIREGS *ar = opaque;
435     switch (addr) {
436     case 0:
437         return acpi_pm1_evt_get_sts(ar);
438     case 2:
439         return ar->pm1.evt.en;
440     default:
441         return 0;
442     }
443 }
444 
445 static void acpi_pm_evt_write(void *opaque, hwaddr addr, uint64_t val,
446                               unsigned width)
447 {
448     ACPIREGS *ar = opaque;
449     switch (addr) {
450     case 0:
451         acpi_pm1_evt_write_sts(ar, val);
452         ar->pm1.evt.update_sci(ar);
453         break;
454     case 2:
455         acpi_pm1_evt_write_en(ar, val);
456         ar->pm1.evt.update_sci(ar);
457         break;
458     }
459 }
460 
461 static const MemoryRegionOps acpi_pm_evt_ops = {
462     .read = acpi_pm_evt_read,
463     .write = acpi_pm_evt_write,
464     .valid.min_access_size = 2,
465     .valid.max_access_size = 2,
466     .endianness = DEVICE_LITTLE_ENDIAN,
467 };
468 
469 void acpi_pm1_evt_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
470                        MemoryRegion *parent)
471 {
472     ar->pm1.evt.update_sci = update_sci;
473     memory_region_init_io(&ar->pm1.evt.io, memory_region_owner(parent),
474                           &acpi_pm_evt_ops, ar, "acpi-evt", 4);
475     memory_region_add_subregion(parent, 0, &ar->pm1.evt.io);
476 }
477 
478 /* ACPI PM_TMR */
479 void acpi_pm_tmr_update(ACPIREGS *ar, bool enable)
480 {
481     int64_t expire_time;
482 
483     /* schedule a timer interruption if needed */
484     if (enable) {
485         expire_time = muldiv64(ar->tmr.overflow_time, NANOSECONDS_PER_SECOND,
486                                PM_TIMER_FREQUENCY);
487         timer_mod(ar->tmr.timer, expire_time);
488     } else {
489         timer_del(ar->tmr.timer);
490     }
491 }
492 
493 static inline int64_t acpi_pm_tmr_get_clock(void)
494 {
495     return muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL), PM_TIMER_FREQUENCY,
496                     NANOSECONDS_PER_SECOND);
497 }
498 
499 void acpi_pm_tmr_calc_overflow_time(ACPIREGS *ar)
500 {
501     int64_t d = acpi_pm_tmr_get_clock();
502     ar->tmr.overflow_time = (d + 0x800000LL) & ~0x7fffffLL;
503 }
504 
505 static uint32_t acpi_pm_tmr_get(ACPIREGS *ar)
506 {
507     uint32_t d = acpi_pm_tmr_get_clock();
508     return d & 0xffffff;
509 }
510 
511 static void acpi_pm_tmr_timer(void *opaque)
512 {
513     ACPIREGS *ar = opaque;
514 
515     qemu_system_wakeup_request(QEMU_WAKEUP_REASON_PMTIMER, NULL);
516     ar->tmr.update_sci(ar);
517 }
518 
519 static uint64_t acpi_pm_tmr_read(void *opaque, hwaddr addr, unsigned width)
520 {
521     return acpi_pm_tmr_get(opaque);
522 }
523 
524 static void acpi_pm_tmr_write(void *opaque, hwaddr addr, uint64_t val,
525                               unsigned width)
526 {
527     /* nothing */
528 }
529 
530 static const MemoryRegionOps acpi_pm_tmr_ops = {
531     .read = acpi_pm_tmr_read,
532     .write = acpi_pm_tmr_write,
533     .valid.min_access_size = 4,
534     .valid.max_access_size = 4,
535     .endianness = DEVICE_LITTLE_ENDIAN,
536 };
537 
538 void acpi_pm_tmr_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
539                       MemoryRegion *parent)
540 {
541     ar->tmr.update_sci = update_sci;
542     ar->tmr.timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, acpi_pm_tmr_timer, ar);
543     memory_region_init_io(&ar->tmr.io, memory_region_owner(parent),
544                           &acpi_pm_tmr_ops, ar, "acpi-tmr", 4);
545     memory_region_add_subregion(parent, 8, &ar->tmr.io);
546 }
547 
548 void acpi_pm_tmr_reset(ACPIREGS *ar)
549 {
550     ar->tmr.overflow_time = 0;
551     timer_del(ar->tmr.timer);
552 }
553 
554 /* ACPI PM1aCNT */
555 static void acpi_pm1_cnt_write(ACPIREGS *ar, uint16_t val)
556 {
557     ar->pm1.cnt.cnt = val & ~(ACPI_BITMASK_SLEEP_ENABLE);
558 
559     if (val & ACPI_BITMASK_SLEEP_ENABLE) {
560         /* change suspend type */
561         uint16_t sus_typ = (val >> 10) & 7;
562         switch(sus_typ) {
563         case 0: /* soft power off */
564             qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
565             break;
566         case 1:
567             qemu_system_suspend_request();
568             break;
569         default:
570             if (sus_typ == ar->pm1.cnt.s4_val) { /* S4 request */
571                 qapi_event_send_suspend_disk();
572                 qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
573             }
574             break;
575         }
576     }
577 }
578 
579 void acpi_pm1_cnt_update(ACPIREGS *ar,
580                          bool sci_enable, bool sci_disable)
581 {
582     /* ACPI specs 3.0, 4.7.2.5 */
583     if (sci_enable) {
584         ar->pm1.cnt.cnt |= ACPI_BITMASK_SCI_ENABLE;
585     } else if (sci_disable) {
586         ar->pm1.cnt.cnt &= ~ACPI_BITMASK_SCI_ENABLE;
587     }
588 }
589 
590 static uint64_t acpi_pm_cnt_read(void *opaque, hwaddr addr, unsigned width)
591 {
592     ACPIREGS *ar = opaque;
593     return ar->pm1.cnt.cnt;
594 }
595 
596 static void acpi_pm_cnt_write(void *opaque, hwaddr addr, uint64_t val,
597                               unsigned width)
598 {
599     acpi_pm1_cnt_write(opaque, val);
600 }
601 
602 static const MemoryRegionOps acpi_pm_cnt_ops = {
603     .read = acpi_pm_cnt_read,
604     .write = acpi_pm_cnt_write,
605     .valid.min_access_size = 2,
606     .valid.max_access_size = 2,
607     .endianness = DEVICE_LITTLE_ENDIAN,
608 };
609 
610 void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent,
611                        bool disable_s3, bool disable_s4, uint8_t s4_val)
612 {
613     FWCfgState *fw_cfg;
614 
615     ar->pm1.cnt.s4_val = s4_val;
616     ar->wakeup.notify = acpi_notify_wakeup;
617     qemu_register_wakeup_notifier(&ar->wakeup);
618 
619     /*
620      * Register wake-up support in QMP query-current-machine API
621      */
622     qemu_register_wakeup_support();
623 
624     memory_region_init_io(&ar->pm1.cnt.io, memory_region_owner(parent),
625                           &acpi_pm_cnt_ops, ar, "acpi-cnt", 2);
626     memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io);
627 
628     fw_cfg = fw_cfg_find();
629     if (fw_cfg) {
630         uint8_t suspend[6] = {128, 0, 0, 129, 128, 128};
631         suspend[3] = 1 | ((!disable_s3) << 7);
632         suspend[4] = s4_val | ((!disable_s4) << 7);
633 
634         fw_cfg_add_file(fw_cfg, "etc/system-states", g_memdup(suspend, 6), 6);
635     }
636 }
637 
638 void acpi_pm1_cnt_reset(ACPIREGS *ar)
639 {
640     ar->pm1.cnt.cnt = 0;
641 }
642 
643 /* ACPI GPE */
644 void acpi_gpe_init(ACPIREGS *ar, uint8_t len)
645 {
646     ar->gpe.len = len;
647     /* Only first len / 2 bytes are ever used,
648      * but the caller in ich9.c migrates full len bytes.
649      * TODO: fix ich9.c and drop the extra allocation.
650      */
651     ar->gpe.sts = g_malloc0(len);
652     ar->gpe.en = g_malloc0(len);
653 }
654 
655 void acpi_gpe_reset(ACPIREGS *ar)
656 {
657     memset(ar->gpe.sts, 0, ar->gpe.len / 2);
658     memset(ar->gpe.en, 0, ar->gpe.len / 2);
659 }
660 
661 static uint8_t *acpi_gpe_ioport_get_ptr(ACPIREGS *ar, uint32_t addr)
662 {
663     uint8_t *cur = NULL;
664 
665     if (addr < ar->gpe.len / 2) {
666         cur = ar->gpe.sts + addr;
667     } else if (addr < ar->gpe.len) {
668         cur = ar->gpe.en + addr - ar->gpe.len / 2;
669     } else {
670         abort();
671     }
672 
673     return cur;
674 }
675 
676 void acpi_gpe_ioport_writeb(ACPIREGS *ar, uint32_t addr, uint32_t val)
677 {
678     uint8_t *cur;
679 
680     cur = acpi_gpe_ioport_get_ptr(ar, addr);
681     if (addr < ar->gpe.len / 2) {
682         /* GPE_STS */
683         *cur = (*cur) & ~val;
684     } else if (addr < ar->gpe.len) {
685         /* GPE_EN */
686         *cur = val;
687     } else {
688         abort();
689     }
690 }
691 
692 uint32_t acpi_gpe_ioport_readb(ACPIREGS *ar, uint32_t addr)
693 {
694     uint8_t *cur;
695     uint32_t val;
696 
697     cur = acpi_gpe_ioport_get_ptr(ar, addr);
698     val = 0;
699     if (cur != NULL) {
700         val = *cur;
701     }
702 
703     return val;
704 }
705 
706 void acpi_send_gpe_event(ACPIREGS *ar, qemu_irq irq,
707                          AcpiEventStatusBits status)
708 {
709     ar->gpe.sts[0] |= status;
710     acpi_update_sci(ar, irq);
711 }
712 
713 void acpi_update_sci(ACPIREGS *regs, qemu_irq irq)
714 {
715     int sci_level, pm1a_sts;
716 
717     pm1a_sts = acpi_pm1_evt_get_sts(regs);
718 
719     sci_level = ((pm1a_sts &
720                   regs->pm1.evt.en & ACPI_BITMASK_PM1_COMMON_ENABLED) != 0) ||
721                 ((regs->gpe.sts[0] & regs->gpe.en[0]) != 0);
722 
723     qemu_set_irq(irq, sci_level);
724 
725     /* schedule a timer interruption if needed */
726     acpi_pm_tmr_update(regs,
727                        (regs->pm1.evt.en & ACPI_BITMASK_TIMER_ENABLE) &&
728                        !(pm1a_sts & ACPI_BITMASK_TIMER_STATUS));
729 }
730