xref: /qemu/hw/intc/apic.c (revision 9277d81f)
1 /*
2  *  APIC support
3  *
4  *  Copyright (c) 2004-2005 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 as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>
18  */
19 #include "qemu/osdep.h"
20 #include "qemu-common.h"
21 #include "cpu.h"
22 #include "qemu/thread.h"
23 #include "hw/i386/apic_internal.h"
24 #include "hw/i386/apic.h"
25 #include "hw/i386/ioapic.h"
26 #include "hw/pci/msi.h"
27 #include "qemu/host-utils.h"
28 #include "trace.h"
29 #include "hw/i386/pc.h"
30 #include "hw/i386/apic-msidef.h"
31 #include "qapi/error.h"
32 
33 #define MAX_APICS 255
34 #define MAX_APIC_WORDS 8
35 
36 #define SYNC_FROM_VAPIC                 0x1
37 #define SYNC_TO_VAPIC                   0x2
38 #define SYNC_ISR_IRR_TO_VAPIC           0x4
39 
40 static APICCommonState *local_apics[MAX_APICS + 1];
41 
42 #define TYPE_APIC "apic"
43 #define APIC(obj) \
44     OBJECT_CHECK(APICCommonState, (obj), TYPE_APIC)
45 
46 static void apic_set_irq(APICCommonState *s, int vector_num, int trigger_mode);
47 static void apic_update_irq(APICCommonState *s);
48 static void apic_get_delivery_bitmask(uint32_t *deliver_bitmask,
49                                       uint8_t dest, uint8_t dest_mode);
50 
51 /* Find first bit starting from msb */
52 static int apic_fls_bit(uint32_t value)
53 {
54     return 31 - clz32(value);
55 }
56 
57 /* Find first bit starting from lsb */
58 static int apic_ffs_bit(uint32_t value)
59 {
60     return ctz32(value);
61 }
62 
63 static inline void apic_reset_bit(uint32_t *tab, int index)
64 {
65     int i, mask;
66     i = index >> 5;
67     mask = 1 << (index & 0x1f);
68     tab[i] &= ~mask;
69 }
70 
71 /* return -1 if no bit is set */
72 static int get_highest_priority_int(uint32_t *tab)
73 {
74     int i;
75     for (i = 7; i >= 0; i--) {
76         if (tab[i] != 0) {
77             return i * 32 + apic_fls_bit(tab[i]);
78         }
79     }
80     return -1;
81 }
82 
83 static void apic_sync_vapic(APICCommonState *s, int sync_type)
84 {
85     VAPICState vapic_state;
86     size_t length;
87     off_t start;
88     int vector;
89 
90     if (!s->vapic_paddr) {
91         return;
92     }
93     if (sync_type & SYNC_FROM_VAPIC) {
94         cpu_physical_memory_read(s->vapic_paddr, &vapic_state,
95                                  sizeof(vapic_state));
96         s->tpr = vapic_state.tpr;
97     }
98     if (sync_type & (SYNC_TO_VAPIC | SYNC_ISR_IRR_TO_VAPIC)) {
99         start = offsetof(VAPICState, isr);
100         length = offsetof(VAPICState, enabled) - offsetof(VAPICState, isr);
101 
102         if (sync_type & SYNC_TO_VAPIC) {
103             assert(qemu_cpu_is_self(CPU(s->cpu)));
104 
105             vapic_state.tpr = s->tpr;
106             vapic_state.enabled = 1;
107             start = 0;
108             length = sizeof(VAPICState);
109         }
110 
111         vector = get_highest_priority_int(s->isr);
112         if (vector < 0) {
113             vector = 0;
114         }
115         vapic_state.isr = vector & 0xf0;
116 
117         vapic_state.zero = 0;
118 
119         vector = get_highest_priority_int(s->irr);
120         if (vector < 0) {
121             vector = 0;
122         }
123         vapic_state.irr = vector & 0xff;
124 
125         cpu_physical_memory_write_rom(&address_space_memory,
126                                       s->vapic_paddr + start,
127                                       ((void *)&vapic_state) + start, length);
128     }
129 }
130 
131 static void apic_vapic_base_update(APICCommonState *s)
132 {
133     apic_sync_vapic(s, SYNC_TO_VAPIC);
134 }
135 
136 static void apic_local_deliver(APICCommonState *s, int vector)
137 {
138     uint32_t lvt = s->lvt[vector];
139     int trigger_mode;
140 
141     trace_apic_local_deliver(vector, (lvt >> 8) & 7);
142 
143     if (lvt & APIC_LVT_MASKED)
144         return;
145 
146     switch ((lvt >> 8) & 7) {
147     case APIC_DM_SMI:
148         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_SMI);
149         break;
150 
151     case APIC_DM_NMI:
152         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_NMI);
153         break;
154 
155     case APIC_DM_EXTINT:
156         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_HARD);
157         break;
158 
159     case APIC_DM_FIXED:
160         trigger_mode = APIC_TRIGGER_EDGE;
161         if ((vector == APIC_LVT_LINT0 || vector == APIC_LVT_LINT1) &&
162             (lvt & APIC_LVT_LEVEL_TRIGGER))
163             trigger_mode = APIC_TRIGGER_LEVEL;
164         apic_set_irq(s, lvt & 0xff, trigger_mode);
165     }
166 }
167 
168 void apic_deliver_pic_intr(DeviceState *dev, int level)
169 {
170     APICCommonState *s = APIC(dev);
171 
172     if (level) {
173         apic_local_deliver(s, APIC_LVT_LINT0);
174     } else {
175         uint32_t lvt = s->lvt[APIC_LVT_LINT0];
176 
177         switch ((lvt >> 8) & 7) {
178         case APIC_DM_FIXED:
179             if (!(lvt & APIC_LVT_LEVEL_TRIGGER))
180                 break;
181             apic_reset_bit(s->irr, lvt & 0xff);
182             /* fall through */
183         case APIC_DM_EXTINT:
184             apic_update_irq(s);
185             break;
186         }
187     }
188 }
189 
190 static void apic_external_nmi(APICCommonState *s)
191 {
192     apic_local_deliver(s, APIC_LVT_LINT1);
193 }
194 
195 #define foreach_apic(apic, deliver_bitmask, code) \
196 {\
197     int __i, __j;\
198     for(__i = 0; __i < MAX_APIC_WORDS; __i++) {\
199         uint32_t __mask = deliver_bitmask[__i];\
200         if (__mask) {\
201             for(__j = 0; __j < 32; __j++) {\
202                 if (__mask & (1U << __j)) {\
203                     apic = local_apics[__i * 32 + __j];\
204                     if (apic) {\
205                         code;\
206                     }\
207                 }\
208             }\
209         }\
210     }\
211 }
212 
213 static void apic_bus_deliver(const uint32_t *deliver_bitmask,
214                              uint8_t delivery_mode, uint8_t vector_num,
215                              uint8_t trigger_mode)
216 {
217     APICCommonState *apic_iter;
218 
219     switch (delivery_mode) {
220         case APIC_DM_LOWPRI:
221             /* XXX: search for focus processor, arbitration */
222             {
223                 int i, d;
224                 d = -1;
225                 for(i = 0; i < MAX_APIC_WORDS; i++) {
226                     if (deliver_bitmask[i]) {
227                         d = i * 32 + apic_ffs_bit(deliver_bitmask[i]);
228                         break;
229                     }
230                 }
231                 if (d >= 0) {
232                     apic_iter = local_apics[d];
233                     if (apic_iter) {
234                         apic_set_irq(apic_iter, vector_num, trigger_mode);
235                     }
236                 }
237             }
238             return;
239 
240         case APIC_DM_FIXED:
241             break;
242 
243         case APIC_DM_SMI:
244             foreach_apic(apic_iter, deliver_bitmask,
245                 cpu_interrupt(CPU(apic_iter->cpu), CPU_INTERRUPT_SMI)
246             );
247             return;
248 
249         case APIC_DM_NMI:
250             foreach_apic(apic_iter, deliver_bitmask,
251                 cpu_interrupt(CPU(apic_iter->cpu), CPU_INTERRUPT_NMI)
252             );
253             return;
254 
255         case APIC_DM_INIT:
256             /* normal INIT IPI sent to processors */
257             foreach_apic(apic_iter, deliver_bitmask,
258                          cpu_interrupt(CPU(apic_iter->cpu),
259                                        CPU_INTERRUPT_INIT)
260             );
261             return;
262 
263         case APIC_DM_EXTINT:
264             /* handled in I/O APIC code */
265             break;
266 
267         default:
268             return;
269     }
270 
271     foreach_apic(apic_iter, deliver_bitmask,
272                  apic_set_irq(apic_iter, vector_num, trigger_mode) );
273 }
274 
275 void apic_deliver_irq(uint8_t dest, uint8_t dest_mode, uint8_t delivery_mode,
276                       uint8_t vector_num, uint8_t trigger_mode)
277 {
278     uint32_t deliver_bitmask[MAX_APIC_WORDS];
279 
280     trace_apic_deliver_irq(dest, dest_mode, delivery_mode, vector_num,
281                            trigger_mode);
282 
283     apic_get_delivery_bitmask(deliver_bitmask, dest, dest_mode);
284     apic_bus_deliver(deliver_bitmask, delivery_mode, vector_num, trigger_mode);
285 }
286 
287 static void apic_set_base(APICCommonState *s, uint64_t val)
288 {
289     s->apicbase = (val & 0xfffff000) |
290         (s->apicbase & (MSR_IA32_APICBASE_BSP | MSR_IA32_APICBASE_ENABLE));
291     /* if disabled, cannot be enabled again */
292     if (!(val & MSR_IA32_APICBASE_ENABLE)) {
293         s->apicbase &= ~MSR_IA32_APICBASE_ENABLE;
294         cpu_clear_apic_feature(&s->cpu->env);
295         s->spurious_vec &= ~APIC_SV_ENABLE;
296     }
297 }
298 
299 static void apic_set_tpr(APICCommonState *s, uint8_t val)
300 {
301     /* Updates from cr8 are ignored while the VAPIC is active */
302     if (!s->vapic_paddr) {
303         s->tpr = val << 4;
304         apic_update_irq(s);
305     }
306 }
307 
308 int apic_get_highest_priority_irr(DeviceState *dev)
309 {
310     APICCommonState *s;
311 
312     if (!dev) {
313         /* no interrupts */
314         return -1;
315     }
316     s = APIC_COMMON(dev);
317     return get_highest_priority_int(s->irr);
318 }
319 
320 static uint8_t apic_get_tpr(APICCommonState *s)
321 {
322     apic_sync_vapic(s, SYNC_FROM_VAPIC);
323     return s->tpr >> 4;
324 }
325 
326 int apic_get_ppr(APICCommonState *s)
327 {
328     int tpr, isrv, ppr;
329 
330     tpr = (s->tpr >> 4);
331     isrv = get_highest_priority_int(s->isr);
332     if (isrv < 0)
333         isrv = 0;
334     isrv >>= 4;
335     if (tpr >= isrv)
336         ppr = s->tpr;
337     else
338         ppr = isrv << 4;
339     return ppr;
340 }
341 
342 static int apic_get_arb_pri(APICCommonState *s)
343 {
344     /* XXX: arbitration */
345     return 0;
346 }
347 
348 
349 /*
350  * <0 - low prio interrupt,
351  * 0  - no interrupt,
352  * >0 - interrupt number
353  */
354 static int apic_irq_pending(APICCommonState *s)
355 {
356     int irrv, ppr;
357 
358     if (!(s->spurious_vec & APIC_SV_ENABLE)) {
359         return 0;
360     }
361 
362     irrv = get_highest_priority_int(s->irr);
363     if (irrv < 0) {
364         return 0;
365     }
366     ppr = apic_get_ppr(s);
367     if (ppr && (irrv & 0xf0) <= (ppr & 0xf0)) {
368         return -1;
369     }
370 
371     return irrv;
372 }
373 
374 /* signal the CPU if an irq is pending */
375 static void apic_update_irq(APICCommonState *s)
376 {
377     CPUState *cpu;
378     DeviceState *dev = (DeviceState *)s;
379 
380     cpu = CPU(s->cpu);
381     if (!qemu_cpu_is_self(cpu)) {
382         cpu_interrupt(cpu, CPU_INTERRUPT_POLL);
383     } else if (apic_irq_pending(s) > 0) {
384         cpu_interrupt(cpu, CPU_INTERRUPT_HARD);
385     } else if (!apic_accept_pic_intr(dev) || !pic_get_output(isa_pic)) {
386         cpu_reset_interrupt(cpu, CPU_INTERRUPT_HARD);
387     }
388 }
389 
390 void apic_poll_irq(DeviceState *dev)
391 {
392     APICCommonState *s = APIC(dev);
393 
394     apic_sync_vapic(s, SYNC_FROM_VAPIC);
395     apic_update_irq(s);
396 }
397 
398 static void apic_set_irq(APICCommonState *s, int vector_num, int trigger_mode)
399 {
400     apic_report_irq_delivered(!apic_get_bit(s->irr, vector_num));
401 
402     apic_set_bit(s->irr, vector_num);
403     if (trigger_mode)
404         apic_set_bit(s->tmr, vector_num);
405     else
406         apic_reset_bit(s->tmr, vector_num);
407     if (s->vapic_paddr) {
408         apic_sync_vapic(s, SYNC_ISR_IRR_TO_VAPIC);
409         /*
410          * The vcpu thread needs to see the new IRR before we pull its current
411          * TPR value. That way, if we miss a lowering of the TRP, the guest
412          * has the chance to notice the new IRR and poll for IRQs on its own.
413          */
414         smp_wmb();
415         apic_sync_vapic(s, SYNC_FROM_VAPIC);
416     }
417     apic_update_irq(s);
418 }
419 
420 static void apic_eoi(APICCommonState *s)
421 {
422     int isrv;
423     isrv = get_highest_priority_int(s->isr);
424     if (isrv < 0)
425         return;
426     apic_reset_bit(s->isr, isrv);
427     if (!(s->spurious_vec & APIC_SV_DIRECTED_IO) && apic_get_bit(s->tmr, isrv)) {
428         ioapic_eoi_broadcast(isrv);
429     }
430     apic_sync_vapic(s, SYNC_FROM_VAPIC | SYNC_TO_VAPIC);
431     apic_update_irq(s);
432 }
433 
434 static int apic_find_dest(uint8_t dest)
435 {
436     APICCommonState *apic = local_apics[dest];
437     int i;
438 
439     if (apic && apic->id == dest)
440         return dest;  /* shortcut in case apic->id == local_apics[dest]->id */
441 
442     for (i = 0; i < MAX_APICS; i++) {
443         apic = local_apics[i];
444 	if (apic && apic->id == dest)
445             return i;
446         if (!apic)
447             break;
448     }
449 
450     return -1;
451 }
452 
453 static void apic_get_delivery_bitmask(uint32_t *deliver_bitmask,
454                                       uint8_t dest, uint8_t dest_mode)
455 {
456     APICCommonState *apic_iter;
457     int i;
458 
459     if (dest_mode == 0) {
460         if (dest == 0xff) {
461             memset(deliver_bitmask, 0xff, MAX_APIC_WORDS * sizeof(uint32_t));
462         } else {
463             int idx = apic_find_dest(dest);
464             memset(deliver_bitmask, 0x00, MAX_APIC_WORDS * sizeof(uint32_t));
465             if (idx >= 0)
466                 apic_set_bit(deliver_bitmask, idx);
467         }
468     } else {
469         /* XXX: cluster mode */
470         memset(deliver_bitmask, 0x00, MAX_APIC_WORDS * sizeof(uint32_t));
471         for(i = 0; i < MAX_APICS; i++) {
472             apic_iter = local_apics[i];
473             if (apic_iter) {
474                 if (apic_iter->dest_mode == 0xf) {
475                     if (dest & apic_iter->log_dest)
476                         apic_set_bit(deliver_bitmask, i);
477                 } else if (apic_iter->dest_mode == 0x0) {
478                     if ((dest & 0xf0) == (apic_iter->log_dest & 0xf0) &&
479                         (dest & apic_iter->log_dest & 0x0f)) {
480                         apic_set_bit(deliver_bitmask, i);
481                     }
482                 }
483             } else {
484                 break;
485             }
486         }
487     }
488 }
489 
490 static void apic_startup(APICCommonState *s, int vector_num)
491 {
492     s->sipi_vector = vector_num;
493     cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_SIPI);
494 }
495 
496 void apic_sipi(DeviceState *dev)
497 {
498     APICCommonState *s = APIC(dev);
499 
500     cpu_reset_interrupt(CPU(s->cpu), CPU_INTERRUPT_SIPI);
501 
502     if (!s->wait_for_sipi)
503         return;
504     cpu_x86_load_seg_cache_sipi(s->cpu, s->sipi_vector);
505     s->wait_for_sipi = 0;
506 }
507 
508 static void apic_deliver(DeviceState *dev, uint8_t dest, uint8_t dest_mode,
509                          uint8_t delivery_mode, uint8_t vector_num,
510                          uint8_t trigger_mode)
511 {
512     APICCommonState *s = APIC(dev);
513     uint32_t deliver_bitmask[MAX_APIC_WORDS];
514     int dest_shorthand = (s->icr[0] >> 18) & 3;
515     APICCommonState *apic_iter;
516 
517     switch (dest_shorthand) {
518     case 0:
519         apic_get_delivery_bitmask(deliver_bitmask, dest, dest_mode);
520         break;
521     case 1:
522         memset(deliver_bitmask, 0x00, sizeof(deliver_bitmask));
523         apic_set_bit(deliver_bitmask, s->id);
524         break;
525     case 2:
526         memset(deliver_bitmask, 0xff, sizeof(deliver_bitmask));
527         break;
528     case 3:
529         memset(deliver_bitmask, 0xff, sizeof(deliver_bitmask));
530         apic_reset_bit(deliver_bitmask, s->id);
531         break;
532     }
533 
534     switch (delivery_mode) {
535         case APIC_DM_INIT:
536             {
537                 int trig_mode = (s->icr[0] >> 15) & 1;
538                 int level = (s->icr[0] >> 14) & 1;
539                 if (level == 0 && trig_mode == 1) {
540                     foreach_apic(apic_iter, deliver_bitmask,
541                                  apic_iter->arb_id = apic_iter->id );
542                     return;
543                 }
544             }
545             break;
546 
547         case APIC_DM_SIPI:
548             foreach_apic(apic_iter, deliver_bitmask,
549                          apic_startup(apic_iter, vector_num) );
550             return;
551     }
552 
553     apic_bus_deliver(deliver_bitmask, delivery_mode, vector_num, trigger_mode);
554 }
555 
556 static bool apic_check_pic(APICCommonState *s)
557 {
558     DeviceState *dev = (DeviceState *)s;
559 
560     if (!apic_accept_pic_intr(dev) || !pic_get_output(isa_pic)) {
561         return false;
562     }
563     apic_deliver_pic_intr(dev, 1);
564     return true;
565 }
566 
567 int apic_get_interrupt(DeviceState *dev)
568 {
569     APICCommonState *s = APIC(dev);
570     int intno;
571 
572     /* if the APIC is installed or enabled, we let the 8259 handle the
573        IRQs */
574     if (!s)
575         return -1;
576     if (!(s->spurious_vec & APIC_SV_ENABLE))
577         return -1;
578 
579     apic_sync_vapic(s, SYNC_FROM_VAPIC);
580     intno = apic_irq_pending(s);
581 
582     /* if there is an interrupt from the 8259, let the caller handle
583      * that first since ExtINT interrupts ignore the priority.
584      */
585     if (intno == 0 || apic_check_pic(s)) {
586         apic_sync_vapic(s, SYNC_TO_VAPIC);
587         return -1;
588     } else if (intno < 0) {
589         apic_sync_vapic(s, SYNC_TO_VAPIC);
590         return s->spurious_vec & 0xff;
591     }
592     apic_reset_bit(s->irr, intno);
593     apic_set_bit(s->isr, intno);
594     apic_sync_vapic(s, SYNC_TO_VAPIC);
595 
596     apic_update_irq(s);
597 
598     return intno;
599 }
600 
601 int apic_accept_pic_intr(DeviceState *dev)
602 {
603     APICCommonState *s = APIC(dev);
604     uint32_t lvt0;
605 
606     if (!s)
607         return -1;
608 
609     lvt0 = s->lvt[APIC_LVT_LINT0];
610 
611     if ((s->apicbase & MSR_IA32_APICBASE_ENABLE) == 0 ||
612         (lvt0 & APIC_LVT_MASKED) == 0)
613         return 1;
614 
615     return 0;
616 }
617 
618 static uint32_t apic_get_current_count(APICCommonState *s)
619 {
620     int64_t d;
621     uint32_t val;
622     d = (qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - s->initial_count_load_time) >>
623         s->count_shift;
624     if (s->lvt[APIC_LVT_TIMER] & APIC_LVT_TIMER_PERIODIC) {
625         /* periodic */
626         val = s->initial_count - (d % ((uint64_t)s->initial_count + 1));
627     } else {
628         if (d >= s->initial_count)
629             val = 0;
630         else
631             val = s->initial_count - d;
632     }
633     return val;
634 }
635 
636 static void apic_timer_update(APICCommonState *s, int64_t current_time)
637 {
638     if (apic_next_timer(s, current_time)) {
639         timer_mod(s->timer, s->next_time);
640     } else {
641         timer_del(s->timer);
642     }
643 }
644 
645 static void apic_timer(void *opaque)
646 {
647     APICCommonState *s = opaque;
648 
649     apic_local_deliver(s, APIC_LVT_TIMER);
650     apic_timer_update(s, s->next_time);
651 }
652 
653 static uint32_t apic_mem_readb(void *opaque, hwaddr addr)
654 {
655     return 0;
656 }
657 
658 static uint32_t apic_mem_readw(void *opaque, hwaddr addr)
659 {
660     return 0;
661 }
662 
663 static void apic_mem_writeb(void *opaque, hwaddr addr, uint32_t val)
664 {
665 }
666 
667 static void apic_mem_writew(void *opaque, hwaddr addr, uint32_t val)
668 {
669 }
670 
671 static uint32_t apic_mem_readl(void *opaque, hwaddr addr)
672 {
673     DeviceState *dev;
674     APICCommonState *s;
675     uint32_t val;
676     int index;
677 
678     dev = cpu_get_current_apic();
679     if (!dev) {
680         return 0;
681     }
682     s = APIC(dev);
683 
684     index = (addr >> 4) & 0xff;
685     switch(index) {
686     case 0x02: /* id */
687         val = s->id << 24;
688         break;
689     case 0x03: /* version */
690         val = s->version | ((APIC_LVT_NB - 1) << 16);
691         break;
692     case 0x08:
693         apic_sync_vapic(s, SYNC_FROM_VAPIC);
694         if (apic_report_tpr_access) {
695             cpu_report_tpr_access(&s->cpu->env, TPR_ACCESS_READ);
696         }
697         val = s->tpr;
698         break;
699     case 0x09:
700         val = apic_get_arb_pri(s);
701         break;
702     case 0x0a:
703         /* ppr */
704         val = apic_get_ppr(s);
705         break;
706     case 0x0b:
707         val = 0;
708         break;
709     case 0x0d:
710         val = s->log_dest << 24;
711         break;
712     case 0x0e:
713         val = (s->dest_mode << 28) | 0xfffffff;
714         break;
715     case 0x0f:
716         val = s->spurious_vec;
717         break;
718     case 0x10 ... 0x17:
719         val = s->isr[index & 7];
720         break;
721     case 0x18 ... 0x1f:
722         val = s->tmr[index & 7];
723         break;
724     case 0x20 ... 0x27:
725         val = s->irr[index & 7];
726         break;
727     case 0x28:
728         val = s->esr;
729         break;
730     case 0x30:
731     case 0x31:
732         val = s->icr[index & 1];
733         break;
734     case 0x32 ... 0x37:
735         val = s->lvt[index - 0x32];
736         break;
737     case 0x38:
738         val = s->initial_count;
739         break;
740     case 0x39:
741         val = apic_get_current_count(s);
742         break;
743     case 0x3e:
744         val = s->divide_conf;
745         break;
746     default:
747         s->esr |= APIC_ESR_ILLEGAL_ADDRESS;
748         val = 0;
749         break;
750     }
751     trace_apic_mem_readl(addr, val);
752     return val;
753 }
754 
755 static void apic_send_msi(MSIMessage *msi)
756 {
757     uint64_t addr = msi->address;
758     uint32_t data = msi->data;
759     uint8_t dest = (addr & MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
760     uint8_t vector = (data & MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
761     uint8_t dest_mode = (addr >> MSI_ADDR_DEST_MODE_SHIFT) & 0x1;
762     uint8_t trigger_mode = (data >> MSI_DATA_TRIGGER_SHIFT) & 0x1;
763     uint8_t delivery = (data >> MSI_DATA_DELIVERY_MODE_SHIFT) & 0x7;
764     /* XXX: Ignore redirection hint. */
765     apic_deliver_irq(dest, dest_mode, delivery, vector, trigger_mode);
766 }
767 
768 static void apic_mem_writel(void *opaque, hwaddr addr, uint32_t val)
769 {
770     DeviceState *dev;
771     APICCommonState *s;
772     int index = (addr >> 4) & 0xff;
773     if (addr > 0xfff || !index) {
774         /* MSI and MMIO APIC are at the same memory location,
775          * but actually not on the global bus: MSI is on PCI bus
776          * APIC is connected directly to the CPU.
777          * Mapping them on the global bus happens to work because
778          * MSI registers are reserved in APIC MMIO and vice versa. */
779         MSIMessage msi = { .address = addr, .data = val };
780         apic_send_msi(&msi);
781         return;
782     }
783 
784     dev = cpu_get_current_apic();
785     if (!dev) {
786         return;
787     }
788     s = APIC(dev);
789 
790     trace_apic_mem_writel(addr, val);
791 
792     switch(index) {
793     case 0x02:
794         s->id = (val >> 24);
795         break;
796     case 0x03:
797         break;
798     case 0x08:
799         if (apic_report_tpr_access) {
800             cpu_report_tpr_access(&s->cpu->env, TPR_ACCESS_WRITE);
801         }
802         s->tpr = val;
803         apic_sync_vapic(s, SYNC_TO_VAPIC);
804         apic_update_irq(s);
805         break;
806     case 0x09:
807     case 0x0a:
808         break;
809     case 0x0b: /* EOI */
810         apic_eoi(s);
811         break;
812     case 0x0d:
813         s->log_dest = val >> 24;
814         break;
815     case 0x0e:
816         s->dest_mode = val >> 28;
817         break;
818     case 0x0f:
819         s->spurious_vec = val & 0x1ff;
820         apic_update_irq(s);
821         break;
822     case 0x10 ... 0x17:
823     case 0x18 ... 0x1f:
824     case 0x20 ... 0x27:
825     case 0x28:
826         break;
827     case 0x30:
828         s->icr[0] = val;
829         apic_deliver(dev, (s->icr[1] >> 24) & 0xff, (s->icr[0] >> 11) & 1,
830                      (s->icr[0] >> 8) & 7, (s->icr[0] & 0xff),
831                      (s->icr[0] >> 15) & 1);
832         break;
833     case 0x31:
834         s->icr[1] = val;
835         break;
836     case 0x32 ... 0x37:
837         {
838             int n = index - 0x32;
839             s->lvt[n] = val;
840             if (n == APIC_LVT_TIMER) {
841                 apic_timer_update(s, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
842             } else if (n == APIC_LVT_LINT0 && apic_check_pic(s)) {
843                 apic_update_irq(s);
844             }
845         }
846         break;
847     case 0x38:
848         s->initial_count = val;
849         s->initial_count_load_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
850         apic_timer_update(s, s->initial_count_load_time);
851         break;
852     case 0x39:
853         break;
854     case 0x3e:
855         {
856             int v;
857             s->divide_conf = val & 0xb;
858             v = (s->divide_conf & 3) | ((s->divide_conf >> 1) & 4);
859             s->count_shift = (v + 1) & 7;
860         }
861         break;
862     default:
863         s->esr |= APIC_ESR_ILLEGAL_ADDRESS;
864         break;
865     }
866 }
867 
868 static void apic_pre_save(APICCommonState *s)
869 {
870     apic_sync_vapic(s, SYNC_FROM_VAPIC);
871 }
872 
873 static void apic_post_load(APICCommonState *s)
874 {
875     if (s->timer_expiry != -1) {
876         timer_mod(s->timer, s->timer_expiry);
877     } else {
878         timer_del(s->timer);
879     }
880 }
881 
882 static const MemoryRegionOps apic_io_ops = {
883     .old_mmio = {
884         .read = { apic_mem_readb, apic_mem_readw, apic_mem_readl, },
885         .write = { apic_mem_writeb, apic_mem_writew, apic_mem_writel, },
886     },
887     .endianness = DEVICE_NATIVE_ENDIAN,
888 };
889 
890 static void apic_realize(DeviceState *dev, Error **errp)
891 {
892     APICCommonState *s = APIC(dev);
893 
894     if (s->id >= MAX_APICS) {
895         error_setg(errp, "%s initialization failed. APIC ID %d is invalid",
896                    object_get_typename(OBJECT(dev)), s->id);
897         return;
898     }
899 
900     memory_region_init_io(&s->io_memory, OBJECT(s), &apic_io_ops, s, "apic-msi",
901                           APIC_SPACE_SIZE);
902 
903     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, apic_timer, s);
904     local_apics[s->id] = s;
905 
906     msi_nonbroken = true;
907 }
908 
909 static void apic_unrealize(DeviceState *dev, Error **errp)
910 {
911     APICCommonState *s = APIC(dev);
912 
913     timer_del(s->timer);
914     timer_free(s->timer);
915     local_apics[s->id] = NULL;
916 }
917 
918 static void apic_class_init(ObjectClass *klass, void *data)
919 {
920     APICCommonClass *k = APIC_COMMON_CLASS(klass);
921 
922     k->realize = apic_realize;
923     k->unrealize = apic_unrealize;
924     k->set_base = apic_set_base;
925     k->set_tpr = apic_set_tpr;
926     k->get_tpr = apic_get_tpr;
927     k->vapic_base_update = apic_vapic_base_update;
928     k->external_nmi = apic_external_nmi;
929     k->pre_save = apic_pre_save;
930     k->post_load = apic_post_load;
931     k->send_msi = apic_send_msi;
932 }
933 
934 static const TypeInfo apic_info = {
935     .name          = TYPE_APIC,
936     .instance_size = sizeof(APICCommonState),
937     .parent        = TYPE_APIC_COMMON,
938     .class_init    = apic_class_init,
939 };
940 
941 static void apic_register_types(void)
942 {
943     type_register_static(&apic_info);
944 }
945 
946 type_init(apic_register_types)
947