xref: /openbmc/qemu/hw/intc/apic.c (revision 8acf8650)
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 2.1 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/thread.h"
21 #include "qemu/error-report.h"
22 #include "hw/i386/apic_internal.h"
23 #include "hw/i386/apic.h"
24 #include "hw/intc/ioapic.h"
25 #include "hw/intc/i8259.h"
26 #include "hw/intc/kvm_irqcount.h"
27 #include "hw/pci/msi.h"
28 #include "qemu/host-utils.h"
29 #include "sysemu/kvm.h"
30 #include "trace.h"
31 #include "hw/i386/apic-msidef.h"
32 #include "qapi/error.h"
33 #include "qom/object.h"
34 
35 #define MAX_APICS 255
36 #define MAX_APIC_WORDS 8
37 
38 #define SYNC_FROM_VAPIC                 0x1
39 #define SYNC_TO_VAPIC                   0x2
40 #define SYNC_ISR_IRR_TO_VAPIC           0x4
41 
42 static APICCommonState *local_apics[MAX_APICS + 1];
43 
44 #define TYPE_APIC "apic"
45 /*This is reusing the APICCommonState typedef from APIC_COMMON */
46 DECLARE_INSTANCE_CHECKER(APICCommonState, APIC,
47                          TYPE_APIC)
48 
49 static void apic_set_irq(APICCommonState *s, int vector_num, int trigger_mode);
50 static void apic_update_irq(APICCommonState *s);
51 static void apic_get_delivery_bitmask(uint32_t *deliver_bitmask,
52                                       uint8_t dest, uint8_t dest_mode);
53 
54 /* Find first bit starting from msb */
55 static int apic_fls_bit(uint32_t value)
56 {
57     return 31 - clz32(value);
58 }
59 
60 /* Find first bit starting from lsb */
61 static int apic_ffs_bit(uint32_t value)
62 {
63     return ctz32(value);
64 }
65 
66 static inline void apic_reset_bit(uint32_t *tab, int index)
67 {
68     int i, mask;
69     i = index >> 5;
70     mask = 1 << (index & 0x1f);
71     tab[i] &= ~mask;
72 }
73 
74 /* return -1 if no bit is set */
75 static int get_highest_priority_int(uint32_t *tab)
76 {
77     int i;
78     for (i = 7; i >= 0; i--) {
79         if (tab[i] != 0) {
80             return i * 32 + apic_fls_bit(tab[i]);
81         }
82     }
83     return -1;
84 }
85 
86 static void apic_sync_vapic(APICCommonState *s, int sync_type)
87 {
88     VAPICState vapic_state;
89     size_t length;
90     off_t start;
91     int vector;
92 
93     if (!s->vapic_paddr) {
94         return;
95     }
96     if (sync_type & SYNC_FROM_VAPIC) {
97         cpu_physical_memory_read(s->vapic_paddr, &vapic_state,
98                                  sizeof(vapic_state));
99         s->tpr = vapic_state.tpr;
100     }
101     if (sync_type & (SYNC_TO_VAPIC | SYNC_ISR_IRR_TO_VAPIC)) {
102         start = offsetof(VAPICState, isr);
103         length = offsetof(VAPICState, enabled) - offsetof(VAPICState, isr);
104 
105         if (sync_type & SYNC_TO_VAPIC) {
106             assert(qemu_cpu_is_self(CPU(s->cpu)));
107 
108             vapic_state.tpr = s->tpr;
109             vapic_state.enabled = 1;
110             start = 0;
111             length = sizeof(VAPICState);
112         }
113 
114         vector = get_highest_priority_int(s->isr);
115         if (vector < 0) {
116             vector = 0;
117         }
118         vapic_state.isr = vector & 0xf0;
119 
120         vapic_state.zero = 0;
121 
122         vector = get_highest_priority_int(s->irr);
123         if (vector < 0) {
124             vector = 0;
125         }
126         vapic_state.irr = vector & 0xff;
127 
128         address_space_write_rom(&address_space_memory,
129                                 s->vapic_paddr + start,
130                                 MEMTXATTRS_UNSPECIFIED,
131                                 ((void *)&vapic_state) + start, length);
132     }
133 }
134 
135 static void apic_vapic_base_update(APICCommonState *s)
136 {
137     apic_sync_vapic(s, SYNC_TO_VAPIC);
138 }
139 
140 static void apic_local_deliver(APICCommonState *s, int vector)
141 {
142     uint32_t lvt = s->lvt[vector];
143     int trigger_mode;
144 
145     trace_apic_local_deliver(vector, (lvt >> 8) & 7);
146 
147     if (lvt & APIC_LVT_MASKED)
148         return;
149 
150     switch ((lvt >> 8) & 7) {
151     case APIC_DM_SMI:
152         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_SMI);
153         break;
154 
155     case APIC_DM_NMI:
156         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_NMI);
157         break;
158 
159     case APIC_DM_EXTINT:
160         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_HARD);
161         break;
162 
163     case APIC_DM_FIXED:
164         trigger_mode = APIC_TRIGGER_EDGE;
165         if ((vector == APIC_LVT_LINT0 || vector == APIC_LVT_LINT1) &&
166             (lvt & APIC_LVT_LEVEL_TRIGGER))
167             trigger_mode = APIC_TRIGGER_LEVEL;
168         apic_set_irq(s, lvt & 0xff, trigger_mode);
169     }
170 }
171 
172 void apic_deliver_pic_intr(DeviceState *dev, int level)
173 {
174     APICCommonState *s = APIC(dev);
175 
176     if (level) {
177         apic_local_deliver(s, APIC_LVT_LINT0);
178     } else {
179         uint32_t lvt = s->lvt[APIC_LVT_LINT0];
180 
181         switch ((lvt >> 8) & 7) {
182         case APIC_DM_FIXED:
183             if (!(lvt & APIC_LVT_LEVEL_TRIGGER))
184                 break;
185             apic_reset_bit(s->irr, lvt & 0xff);
186             /* fall through */
187         case APIC_DM_EXTINT:
188             apic_update_irq(s);
189             break;
190         }
191     }
192 }
193 
194 static void apic_external_nmi(APICCommonState *s)
195 {
196     apic_local_deliver(s, APIC_LVT_LINT1);
197 }
198 
199 #define foreach_apic(apic, deliver_bitmask, code) \
200 {\
201     int __i, __j;\
202     for(__i = 0; __i < MAX_APIC_WORDS; __i++) {\
203         uint32_t __mask = deliver_bitmask[__i];\
204         if (__mask) {\
205             for(__j = 0; __j < 32; __j++) {\
206                 if (__mask & (1U << __j)) {\
207                     apic = local_apics[__i * 32 + __j];\
208                     if (apic) {\
209                         code;\
210                     }\
211                 }\
212             }\
213         }\
214     }\
215 }
216 
217 static void apic_bus_deliver(const uint32_t *deliver_bitmask,
218                              uint8_t delivery_mode, uint8_t vector_num,
219                              uint8_t trigger_mode)
220 {
221     APICCommonState *apic_iter;
222 
223     switch (delivery_mode) {
224         case APIC_DM_LOWPRI:
225             /* XXX: search for focus processor, arbitration */
226             {
227                 int i, d;
228                 d = -1;
229                 for(i = 0; i < MAX_APIC_WORDS; i++) {
230                     if (deliver_bitmask[i]) {
231                         d = i * 32 + apic_ffs_bit(deliver_bitmask[i]);
232                         break;
233                     }
234                 }
235                 if (d >= 0) {
236                     apic_iter = local_apics[d];
237                     if (apic_iter) {
238                         apic_set_irq(apic_iter, vector_num, trigger_mode);
239                     }
240                 }
241             }
242             return;
243 
244         case APIC_DM_FIXED:
245             break;
246 
247         case APIC_DM_SMI:
248             foreach_apic(apic_iter, deliver_bitmask,
249                 cpu_interrupt(CPU(apic_iter->cpu), CPU_INTERRUPT_SMI)
250             );
251             return;
252 
253         case APIC_DM_NMI:
254             foreach_apic(apic_iter, deliver_bitmask,
255                 cpu_interrupt(CPU(apic_iter->cpu), CPU_INTERRUPT_NMI)
256             );
257             return;
258 
259         case APIC_DM_INIT:
260             /* normal INIT IPI sent to processors */
261             foreach_apic(apic_iter, deliver_bitmask,
262                          cpu_interrupt(CPU(apic_iter->cpu),
263                                        CPU_INTERRUPT_INIT)
264             );
265             return;
266 
267         case APIC_DM_EXTINT:
268             /* handled in I/O APIC code */
269             break;
270 
271         default:
272             return;
273     }
274 
275     foreach_apic(apic_iter, deliver_bitmask,
276                  apic_set_irq(apic_iter, vector_num, trigger_mode) );
277 }
278 
279 void apic_deliver_irq(uint8_t dest, uint8_t dest_mode, uint8_t delivery_mode,
280                       uint8_t vector_num, uint8_t trigger_mode)
281 {
282     uint32_t deliver_bitmask[MAX_APIC_WORDS];
283 
284     trace_apic_deliver_irq(dest, dest_mode, delivery_mode, vector_num,
285                            trigger_mode);
286 
287     apic_get_delivery_bitmask(deliver_bitmask, dest, dest_mode);
288     apic_bus_deliver(deliver_bitmask, delivery_mode, vector_num, trigger_mode);
289 }
290 
291 static void apic_set_base(APICCommonState *s, uint64_t val)
292 {
293     s->apicbase = (val & 0xfffff000) |
294         (s->apicbase & (MSR_IA32_APICBASE_BSP | MSR_IA32_APICBASE_ENABLE));
295     /* if disabled, cannot be enabled again */
296     if (!(val & MSR_IA32_APICBASE_ENABLE)) {
297         s->apicbase &= ~MSR_IA32_APICBASE_ENABLE;
298         cpu_clear_apic_feature(&s->cpu->env);
299         s->spurious_vec &= ~APIC_SV_ENABLE;
300     }
301 }
302 
303 static void apic_set_tpr(APICCommonState *s, uint8_t val)
304 {
305     /* Updates from cr8 are ignored while the VAPIC is active */
306     if (!s->vapic_paddr) {
307         s->tpr = val << 4;
308         apic_update_irq(s);
309     }
310 }
311 
312 int apic_get_highest_priority_irr(DeviceState *dev)
313 {
314     APICCommonState *s;
315 
316     if (!dev) {
317         /* no interrupts */
318         return -1;
319     }
320     s = APIC_COMMON(dev);
321     return get_highest_priority_int(s->irr);
322 }
323 
324 static uint8_t apic_get_tpr(APICCommonState *s)
325 {
326     apic_sync_vapic(s, SYNC_FROM_VAPIC);
327     return s->tpr >> 4;
328 }
329 
330 int apic_get_ppr(APICCommonState *s)
331 {
332     int tpr, isrv, ppr;
333 
334     tpr = (s->tpr >> 4);
335     isrv = get_highest_priority_int(s->isr);
336     if (isrv < 0)
337         isrv = 0;
338     isrv >>= 4;
339     if (tpr >= isrv)
340         ppr = s->tpr;
341     else
342         ppr = isrv << 4;
343     return ppr;
344 }
345 
346 static int apic_get_arb_pri(APICCommonState *s)
347 {
348     /* XXX: arbitration */
349     return 0;
350 }
351 
352 
353 /*
354  * <0 - low prio interrupt,
355  * 0  - no interrupt,
356  * >0 - interrupt number
357  */
358 static int apic_irq_pending(APICCommonState *s)
359 {
360     int irrv, ppr;
361 
362     if (!(s->spurious_vec & APIC_SV_ENABLE)) {
363         return 0;
364     }
365 
366     irrv = get_highest_priority_int(s->irr);
367     if (irrv < 0) {
368         return 0;
369     }
370     ppr = apic_get_ppr(s);
371     if (ppr && (irrv & 0xf0) <= (ppr & 0xf0)) {
372         return -1;
373     }
374 
375     return irrv;
376 }
377 
378 /* signal the CPU if an irq is pending */
379 static void apic_update_irq(APICCommonState *s)
380 {
381     CPUState *cpu;
382     DeviceState *dev = (DeviceState *)s;
383 
384     cpu = CPU(s->cpu);
385     if (!qemu_cpu_is_self(cpu)) {
386         cpu_interrupt(cpu, CPU_INTERRUPT_POLL);
387     } else if (apic_irq_pending(s) > 0) {
388         cpu_interrupt(cpu, CPU_INTERRUPT_HARD);
389     } else if (!apic_accept_pic_intr(dev) || !pic_get_output(isa_pic)) {
390         cpu_reset_interrupt(cpu, CPU_INTERRUPT_HARD);
391     }
392 }
393 
394 void apic_poll_irq(DeviceState *dev)
395 {
396     APICCommonState *s = APIC(dev);
397 
398     apic_sync_vapic(s, SYNC_FROM_VAPIC);
399     apic_update_irq(s);
400 }
401 
402 static void apic_set_irq(APICCommonState *s, int vector_num, int trigger_mode)
403 {
404     kvm_report_irq_delivered(!apic_get_bit(s->irr, vector_num));
405 
406     apic_set_bit(s->irr, vector_num);
407     if (trigger_mode)
408         apic_set_bit(s->tmr, vector_num);
409     else
410         apic_reset_bit(s->tmr, vector_num);
411     if (s->vapic_paddr) {
412         apic_sync_vapic(s, SYNC_ISR_IRR_TO_VAPIC);
413         /*
414          * The vcpu thread needs to see the new IRR before we pull its current
415          * TPR value. That way, if we miss a lowering of the TRP, the guest
416          * has the chance to notice the new IRR and poll for IRQs on its own.
417          */
418         smp_wmb();
419         apic_sync_vapic(s, SYNC_FROM_VAPIC);
420     }
421     apic_update_irq(s);
422 }
423 
424 static void apic_eoi(APICCommonState *s)
425 {
426     int isrv;
427     isrv = get_highest_priority_int(s->isr);
428     if (isrv < 0)
429         return;
430     apic_reset_bit(s->isr, isrv);
431     if (!(s->spurious_vec & APIC_SV_DIRECTED_IO) && apic_get_bit(s->tmr, isrv)) {
432         ioapic_eoi_broadcast(isrv);
433     }
434     apic_sync_vapic(s, SYNC_FROM_VAPIC | SYNC_TO_VAPIC);
435     apic_update_irq(s);
436 }
437 
438 static int apic_find_dest(uint8_t dest)
439 {
440     APICCommonState *apic = local_apics[dest];
441     int i;
442 
443     if (apic && apic->id == dest)
444         return dest;  /* shortcut in case apic->id == local_apics[dest]->id */
445 
446     for (i = 0; i < MAX_APICS; i++) {
447         apic = local_apics[i];
448         if (apic && apic->id == dest)
449             return i;
450         if (!apic)
451             break;
452     }
453 
454     return -1;
455 }
456 
457 static void apic_get_delivery_bitmask(uint32_t *deliver_bitmask,
458                                       uint8_t dest, uint8_t dest_mode)
459 {
460     APICCommonState *apic_iter;
461     int i;
462 
463     if (dest_mode == 0) {
464         if (dest == 0xff) {
465             memset(deliver_bitmask, 0xff, MAX_APIC_WORDS * sizeof(uint32_t));
466         } else {
467             int idx = apic_find_dest(dest);
468             memset(deliver_bitmask, 0x00, MAX_APIC_WORDS * sizeof(uint32_t));
469             if (idx >= 0)
470                 apic_set_bit(deliver_bitmask, idx);
471         }
472     } else {
473         /* XXX: cluster mode */
474         memset(deliver_bitmask, 0x00, MAX_APIC_WORDS * sizeof(uint32_t));
475         for(i = 0; i < MAX_APICS; i++) {
476             apic_iter = local_apics[i];
477             if (apic_iter) {
478                 if (apic_iter->dest_mode == 0xf) {
479                     if (dest & apic_iter->log_dest)
480                         apic_set_bit(deliver_bitmask, i);
481                 } else if (apic_iter->dest_mode == 0x0) {
482                     if ((dest & 0xf0) == (apic_iter->log_dest & 0xf0) &&
483                         (dest & apic_iter->log_dest & 0x0f)) {
484                         apic_set_bit(deliver_bitmask, i);
485                     }
486                 }
487             } else {
488                 break;
489             }
490         }
491     }
492 }
493 
494 static void apic_startup(APICCommonState *s, int vector_num)
495 {
496     s->sipi_vector = vector_num;
497     cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_SIPI);
498 }
499 
500 void apic_sipi(DeviceState *dev)
501 {
502     APICCommonState *s = APIC(dev);
503 
504     cpu_reset_interrupt(CPU(s->cpu), CPU_INTERRUPT_SIPI);
505 
506     if (!s->wait_for_sipi)
507         return;
508     cpu_x86_load_seg_cache_sipi(s->cpu, s->sipi_vector);
509     s->wait_for_sipi = 0;
510 }
511 
512 static void apic_deliver(DeviceState *dev, uint8_t dest, uint8_t dest_mode,
513                          uint8_t delivery_mode, uint8_t vector_num,
514                          uint8_t trigger_mode)
515 {
516     APICCommonState *s = APIC(dev);
517     uint32_t deliver_bitmask[MAX_APIC_WORDS];
518     int dest_shorthand = (s->icr[0] >> 18) & 3;
519     APICCommonState *apic_iter;
520 
521     switch (dest_shorthand) {
522     case 0:
523         apic_get_delivery_bitmask(deliver_bitmask, dest, dest_mode);
524         break;
525     case 1:
526         memset(deliver_bitmask, 0x00, sizeof(deliver_bitmask));
527         apic_set_bit(deliver_bitmask, s->id);
528         break;
529     case 2:
530         memset(deliver_bitmask, 0xff, sizeof(deliver_bitmask));
531         break;
532     case 3:
533         memset(deliver_bitmask, 0xff, sizeof(deliver_bitmask));
534         apic_reset_bit(deliver_bitmask, s->id);
535         break;
536     }
537 
538     switch (delivery_mode) {
539         case APIC_DM_INIT:
540             {
541                 int trig_mode = (s->icr[0] >> 15) & 1;
542                 int level = (s->icr[0] >> 14) & 1;
543                 if (level == 0 && trig_mode == 1) {
544                     foreach_apic(apic_iter, deliver_bitmask,
545                                  apic_iter->arb_id = apic_iter->id );
546                     return;
547                 }
548             }
549             break;
550 
551         case APIC_DM_SIPI:
552             foreach_apic(apic_iter, deliver_bitmask,
553                          apic_startup(apic_iter, vector_num) );
554             return;
555     }
556 
557     apic_bus_deliver(deliver_bitmask, delivery_mode, vector_num, trigger_mode);
558 }
559 
560 static bool apic_check_pic(APICCommonState *s)
561 {
562     DeviceState *dev = (DeviceState *)s;
563 
564     if (!apic_accept_pic_intr(dev) || !pic_get_output(isa_pic)) {
565         return false;
566     }
567     apic_deliver_pic_intr(dev, 1);
568     return true;
569 }
570 
571 int apic_get_interrupt(DeviceState *dev)
572 {
573     APICCommonState *s = APIC(dev);
574     int intno;
575 
576     /* if the APIC is installed or enabled, we let the 8259 handle the
577        IRQs */
578     if (!s)
579         return -1;
580     if (!(s->spurious_vec & APIC_SV_ENABLE))
581         return -1;
582 
583     apic_sync_vapic(s, SYNC_FROM_VAPIC);
584     intno = apic_irq_pending(s);
585 
586     /* if there is an interrupt from the 8259, let the caller handle
587      * that first since ExtINT interrupts ignore the priority.
588      */
589     if (intno == 0 || apic_check_pic(s)) {
590         apic_sync_vapic(s, SYNC_TO_VAPIC);
591         return -1;
592     } else if (intno < 0) {
593         apic_sync_vapic(s, SYNC_TO_VAPIC);
594         return s->spurious_vec & 0xff;
595     }
596     apic_reset_bit(s->irr, intno);
597     apic_set_bit(s->isr, intno);
598     apic_sync_vapic(s, SYNC_TO_VAPIC);
599 
600     apic_update_irq(s);
601 
602     return intno;
603 }
604 
605 int apic_accept_pic_intr(DeviceState *dev)
606 {
607     APICCommonState *s = APIC(dev);
608     uint32_t lvt0;
609 
610     if (!s)
611         return -1;
612 
613     lvt0 = s->lvt[APIC_LVT_LINT0];
614 
615     if ((s->apicbase & MSR_IA32_APICBASE_ENABLE) == 0 ||
616         (lvt0 & APIC_LVT_MASKED) == 0)
617         return isa_pic != NULL;
618 
619     return 0;
620 }
621 
622 static void apic_timer_update(APICCommonState *s, int64_t current_time)
623 {
624     if (apic_next_timer(s, current_time)) {
625         timer_mod(s->timer, s->next_time);
626     } else {
627         timer_del(s->timer);
628     }
629 }
630 
631 static void apic_timer(void *opaque)
632 {
633     APICCommonState *s = opaque;
634 
635     apic_local_deliver(s, APIC_LVT_TIMER);
636     apic_timer_update(s, s->next_time);
637 }
638 
639 static uint64_t apic_mem_read(void *opaque, hwaddr addr, unsigned size)
640 {
641     DeviceState *dev;
642     APICCommonState *s;
643     uint32_t val;
644     int index;
645 
646     if (size < 4) {
647         return 0;
648     }
649 
650     dev = cpu_get_current_apic();
651     if (!dev) {
652         return 0;
653     }
654     s = APIC(dev);
655 
656     index = (addr >> 4) & 0xff;
657     switch(index) {
658     case 0x02: /* id */
659         val = s->id << 24;
660         break;
661     case 0x03: /* version */
662         val = s->version | ((APIC_LVT_NB - 1) << 16);
663         break;
664     case 0x08:
665         apic_sync_vapic(s, SYNC_FROM_VAPIC);
666         if (apic_report_tpr_access) {
667             cpu_report_tpr_access(&s->cpu->env, TPR_ACCESS_READ);
668         }
669         val = s->tpr;
670         break;
671     case 0x09:
672         val = apic_get_arb_pri(s);
673         break;
674     case 0x0a:
675         /* ppr */
676         val = apic_get_ppr(s);
677         break;
678     case 0x0b:
679         val = 0;
680         break;
681     case 0x0d:
682         val = s->log_dest << 24;
683         break;
684     case 0x0e:
685         val = (s->dest_mode << 28) | 0xfffffff;
686         break;
687     case 0x0f:
688         val = s->spurious_vec;
689         break;
690     case 0x10 ... 0x17:
691         val = s->isr[index & 7];
692         break;
693     case 0x18 ... 0x1f:
694         val = s->tmr[index & 7];
695         break;
696     case 0x20 ... 0x27:
697         val = s->irr[index & 7];
698         break;
699     case 0x28:
700         val = s->esr;
701         break;
702     case 0x30:
703     case 0x31:
704         val = s->icr[index & 1];
705         break;
706     case 0x32 ... 0x37:
707         val = s->lvt[index - 0x32];
708         break;
709     case 0x38:
710         val = s->initial_count;
711         break;
712     case 0x39:
713         val = apic_get_current_count(s);
714         break;
715     case 0x3e:
716         val = s->divide_conf;
717         break;
718     default:
719         s->esr |= APIC_ESR_ILLEGAL_ADDRESS;
720         val = 0;
721         break;
722     }
723     trace_apic_mem_readl(addr, val);
724     return val;
725 }
726 
727 static void apic_send_msi(MSIMessage *msi)
728 {
729     uint64_t addr = msi->address;
730     uint32_t data = msi->data;
731     uint8_t dest = (addr & MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
732     uint8_t vector = (data & MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
733     uint8_t dest_mode = (addr >> MSI_ADDR_DEST_MODE_SHIFT) & 0x1;
734     uint8_t trigger_mode = (data >> MSI_DATA_TRIGGER_SHIFT) & 0x1;
735     uint8_t delivery = (data >> MSI_DATA_DELIVERY_MODE_SHIFT) & 0x7;
736     /* XXX: Ignore redirection hint. */
737     apic_deliver_irq(dest, dest_mode, delivery, vector, trigger_mode);
738 }
739 
740 static void apic_mem_write(void *opaque, hwaddr addr, uint64_t val,
741                            unsigned size)
742 {
743     DeviceState *dev;
744     APICCommonState *s;
745     int index = (addr >> 4) & 0xff;
746 
747     if (size < 4) {
748         return;
749     }
750 
751     if (addr > 0xfff || !index) {
752         /* MSI and MMIO APIC are at the same memory location,
753          * but actually not on the global bus: MSI is on PCI bus
754          * APIC is connected directly to the CPU.
755          * Mapping them on the global bus happens to work because
756          * MSI registers are reserved in APIC MMIO and vice versa. */
757         MSIMessage msi = { .address = addr, .data = val };
758         apic_send_msi(&msi);
759         return;
760     }
761 
762     dev = cpu_get_current_apic();
763     if (!dev) {
764         return;
765     }
766     s = APIC(dev);
767 
768     trace_apic_mem_writel(addr, val);
769 
770     switch(index) {
771     case 0x02:
772         s->id = (val >> 24);
773         break;
774     case 0x03:
775         break;
776     case 0x08:
777         if (apic_report_tpr_access) {
778             cpu_report_tpr_access(&s->cpu->env, TPR_ACCESS_WRITE);
779         }
780         s->tpr = val;
781         apic_sync_vapic(s, SYNC_TO_VAPIC);
782         apic_update_irq(s);
783         break;
784     case 0x09:
785     case 0x0a:
786         break;
787     case 0x0b: /* EOI */
788         apic_eoi(s);
789         break;
790     case 0x0d:
791         s->log_dest = val >> 24;
792         break;
793     case 0x0e:
794         s->dest_mode = val >> 28;
795         break;
796     case 0x0f:
797         s->spurious_vec = val & 0x1ff;
798         apic_update_irq(s);
799         break;
800     case 0x10 ... 0x17:
801     case 0x18 ... 0x1f:
802     case 0x20 ... 0x27:
803     case 0x28:
804         break;
805     case 0x30:
806         s->icr[0] = val;
807         apic_deliver(dev, (s->icr[1] >> 24) & 0xff, (s->icr[0] >> 11) & 1,
808                      (s->icr[0] >> 8) & 7, (s->icr[0] & 0xff),
809                      (s->icr[0] >> 15) & 1);
810         break;
811     case 0x31:
812         s->icr[1] = val;
813         break;
814     case 0x32 ... 0x37:
815         {
816             int n = index - 0x32;
817             s->lvt[n] = val;
818             if (n == APIC_LVT_TIMER) {
819                 apic_timer_update(s, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
820             } else if (n == APIC_LVT_LINT0 && apic_check_pic(s)) {
821                 apic_update_irq(s);
822             }
823         }
824         break;
825     case 0x38:
826         s->initial_count = val;
827         s->initial_count_load_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
828         apic_timer_update(s, s->initial_count_load_time);
829         break;
830     case 0x39:
831         break;
832     case 0x3e:
833         {
834             int v;
835             s->divide_conf = val & 0xb;
836             v = (s->divide_conf & 3) | ((s->divide_conf >> 1) & 4);
837             s->count_shift = (v + 1) & 7;
838         }
839         break;
840     default:
841         s->esr |= APIC_ESR_ILLEGAL_ADDRESS;
842         break;
843     }
844 }
845 
846 static void apic_pre_save(APICCommonState *s)
847 {
848     apic_sync_vapic(s, SYNC_FROM_VAPIC);
849 }
850 
851 static void apic_post_load(APICCommonState *s)
852 {
853     if (s->timer_expiry != -1) {
854         timer_mod(s->timer, s->timer_expiry);
855     } else {
856         timer_del(s->timer);
857     }
858 }
859 
860 static const MemoryRegionOps apic_io_ops = {
861     .read = apic_mem_read,
862     .write = apic_mem_write,
863     .impl.min_access_size = 1,
864     .impl.max_access_size = 4,
865     .valid.min_access_size = 1,
866     .valid.max_access_size = 4,
867     .endianness = DEVICE_NATIVE_ENDIAN,
868 };
869 
870 static void apic_realize(DeviceState *dev, Error **errp)
871 {
872     APICCommonState *s = APIC(dev);
873 
874     if (s->id >= MAX_APICS) {
875         error_setg(errp, "%s initialization failed. APIC ID %d is invalid",
876                    object_get_typename(OBJECT(dev)), s->id);
877         return;
878     }
879 
880     if (kvm_enabled()) {
881         warn_report("Userspace local APIC is deprecated for KVM.");
882         warn_report("Do not use kernel-irqchip except for the -M isapc machine type.");
883     }
884 
885     memory_region_init_io(&s->io_memory, OBJECT(s), &apic_io_ops, s, "apic-msi",
886                           APIC_SPACE_SIZE);
887 
888     /*
889      * apic-msi's apic_mem_write can call into ioapic_eoi_broadcast, which can
890      * write back to apic-msi. As such mark the apic-msi region re-entrancy
891      * safe.
892      */
893     s->io_memory.disable_reentrancy_guard = true;
894 
895     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, apic_timer, s);
896     local_apics[s->id] = s;
897 
898     msi_nonbroken = true;
899 }
900 
901 static void apic_unrealize(DeviceState *dev)
902 {
903     APICCommonState *s = APIC(dev);
904 
905     timer_free(s->timer);
906     local_apics[s->id] = NULL;
907 }
908 
909 static void apic_class_init(ObjectClass *klass, void *data)
910 {
911     APICCommonClass *k = APIC_COMMON_CLASS(klass);
912 
913     k->realize = apic_realize;
914     k->unrealize = apic_unrealize;
915     k->set_base = apic_set_base;
916     k->set_tpr = apic_set_tpr;
917     k->get_tpr = apic_get_tpr;
918     k->vapic_base_update = apic_vapic_base_update;
919     k->external_nmi = apic_external_nmi;
920     k->pre_save = apic_pre_save;
921     k->post_load = apic_post_load;
922     k->send_msi = apic_send_msi;
923 }
924 
925 static const TypeInfo apic_info = {
926     .name          = TYPE_APIC,
927     .instance_size = sizeof(APICCommonState),
928     .parent        = TYPE_APIC_COMMON,
929     .class_init    = apic_class_init,
930 };
931 
932 static void apic_register_types(void)
933 {
934     type_register_static(&apic_info);
935 }
936 
937 type_init(apic_register_types)
938