xref: /openbmc/qemu/hw/intc/apic.c (revision cf8dff8d9f92d75bbe16c391464b955fbb0d5720)
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 "system/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 SYNC_FROM_VAPIC                 0x1
36 #define SYNC_TO_VAPIC                   0x2
37 #define SYNC_ISR_IRR_TO_VAPIC           0x4
38 
39 static APICCommonState **local_apics;
40 static uint32_t max_apics;
41 static uint32_t max_apic_words;
42 
43 #define TYPE_APIC "apic"
44 /*This is reusing the APICCommonState typedef from APIC_COMMON */
45 DECLARE_INSTANCE_CHECKER(APICCommonState, APIC,
46                          TYPE_APIC)
47 
48 static void apic_set_irq(APICCommonState *s, int vector_num, int trigger_mode);
49 static void apic_update_irq(APICCommonState *s);
50 static void apic_get_delivery_bitmask(uint32_t *deliver_bitmask,
51                                       uint32_t dest, uint8_t dest_mode);
52 
apic_set_max_apic_id(uint32_t max_apic_id)53 void apic_set_max_apic_id(uint32_t max_apic_id)
54 {
55     int word_size = 32;
56 
57     /* round up the max apic id to next multiple of words */
58     max_apics = (max_apic_id + word_size - 1) & ~(word_size - 1);
59 
60     local_apics = g_malloc0(sizeof(*local_apics) * max_apics);
61     max_apic_words = max_apics >> 5;
62 }
63 
64 
65 /* Find first bit starting from msb */
apic_fls_bit(uint32_t value)66 static int apic_fls_bit(uint32_t value)
67 {
68     return 31 - clz32(value);
69 }
70 
71 /* Find first bit starting from lsb */
apic_ffs_bit(uint32_t value)72 static int apic_ffs_bit(uint32_t value)
73 {
74     return ctz32(value);
75 }
76 
apic_reset_bit(uint32_t * tab,int index)77 static inline void apic_reset_bit(uint32_t *tab, int index)
78 {
79     int i, mask;
80     i = index >> 5;
81     mask = 1 << (index & 0x1f);
82     tab[i] &= ~mask;
83 }
84 
85 /* return -1 if no bit is set */
get_highest_priority_int(uint32_t * tab)86 static int get_highest_priority_int(uint32_t *tab)
87 {
88     int i;
89     for (i = 7; i >= 0; i--) {
90         if (tab[i] != 0) {
91             return i * 32 + apic_fls_bit(tab[i]);
92         }
93     }
94     return -1;
95 }
96 
apic_sync_vapic(APICCommonState * s,int sync_type)97 static void apic_sync_vapic(APICCommonState *s, int sync_type)
98 {
99     VAPICState vapic_state;
100     size_t length;
101     off_t start;
102     int vector;
103 
104     if (!s->vapic_paddr) {
105         return;
106     }
107     if (sync_type & SYNC_FROM_VAPIC) {
108         cpu_physical_memory_read(s->vapic_paddr, &vapic_state,
109                                  sizeof(vapic_state));
110         s->tpr = vapic_state.tpr;
111     }
112     if (sync_type & (SYNC_TO_VAPIC | SYNC_ISR_IRR_TO_VAPIC)) {
113         start = offsetof(VAPICState, isr);
114         length = offsetof(VAPICState, enabled) - offsetof(VAPICState, isr);
115 
116         if (sync_type & SYNC_TO_VAPIC) {
117             assert(qemu_cpu_is_self(CPU(s->cpu)));
118 
119             vapic_state.tpr = s->tpr;
120             vapic_state.enabled = 1;
121             start = 0;
122             length = sizeof(VAPICState);
123         }
124 
125         vector = get_highest_priority_int(s->isr);
126         if (vector < 0) {
127             vector = 0;
128         }
129         vapic_state.isr = vector & 0xf0;
130 
131         vapic_state.zero = 0;
132 
133         vector = get_highest_priority_int(s->irr);
134         if (vector < 0) {
135             vector = 0;
136         }
137         vapic_state.irr = vector & 0xff;
138 
139         address_space_write_rom(&address_space_memory,
140                                 s->vapic_paddr + start,
141                                 MEMTXATTRS_UNSPECIFIED,
142                                 ((void *)&vapic_state) + start, length);
143     }
144 }
145 
apic_vapic_base_update(APICCommonState * s)146 static void apic_vapic_base_update(APICCommonState *s)
147 {
148     apic_sync_vapic(s, SYNC_TO_VAPIC);
149 }
150 
apic_local_deliver(APICCommonState * s,int vector)151 static void apic_local_deliver(APICCommonState *s, int vector)
152 {
153     uint32_t lvt = s->lvt[vector];
154     int trigger_mode;
155 
156     trace_apic_local_deliver(vector, (lvt >> 8) & 7);
157 
158     if (lvt & APIC_LVT_MASKED)
159         return;
160 
161     switch ((lvt >> 8) & 7) {
162     case APIC_DM_SMI:
163         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_SMI);
164         break;
165 
166     case APIC_DM_NMI:
167         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_NMI);
168         break;
169 
170     case APIC_DM_EXTINT:
171         cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_HARD);
172         break;
173 
174     case APIC_DM_FIXED:
175         trigger_mode = APIC_TRIGGER_EDGE;
176         if ((vector == APIC_LVT_LINT0 || vector == APIC_LVT_LINT1) &&
177             (lvt & APIC_LVT_LEVEL_TRIGGER))
178             trigger_mode = APIC_TRIGGER_LEVEL;
179         apic_set_irq(s, lvt & 0xff, trigger_mode);
180     }
181 }
182 
apic_deliver_pic_intr(DeviceState * dev,int level)183 void apic_deliver_pic_intr(DeviceState *dev, int level)
184 {
185     APICCommonState *s = APIC(dev);
186 
187     if (level) {
188         apic_local_deliver(s, APIC_LVT_LINT0);
189     } else {
190         uint32_t lvt = s->lvt[APIC_LVT_LINT0];
191 
192         switch ((lvt >> 8) & 7) {
193         case APIC_DM_FIXED:
194             if (!(lvt & APIC_LVT_LEVEL_TRIGGER))
195                 break;
196             apic_reset_bit(s->irr, lvt & 0xff);
197             /* fall through */
198         case APIC_DM_EXTINT:
199             apic_update_irq(s);
200             break;
201         }
202     }
203 }
204 
apic_external_nmi(APICCommonState * s)205 static void apic_external_nmi(APICCommonState *s)
206 {
207     apic_local_deliver(s, APIC_LVT_LINT1);
208 }
209 
210 #define foreach_apic(apic, deliver_bitmask, code) \
211 {\
212     int __i, __j;\
213     for (__i = 0; __i < max_apic_words; __i++) {\
214         uint32_t __mask = deliver_bitmask[__i];\
215         if (__mask) {\
216             for (__j = 0; __j < 32; __j++) {\
217                 if (__mask & (1U << __j)) {\
218                     apic = local_apics[__i * 32 + __j];\
219                     if (apic) {\
220                         code;\
221                     }\
222                 }\
223             }\
224         }\
225     }\
226 }
227 
apic_bus_deliver(const uint32_t * deliver_bitmask,uint8_t delivery_mode,uint8_t vector_num,uint8_t trigger_mode)228 static void apic_bus_deliver(const uint32_t *deliver_bitmask,
229                              uint8_t delivery_mode, uint8_t vector_num,
230                              uint8_t trigger_mode)
231 {
232     APICCommonState *apic_iter;
233 
234     switch (delivery_mode) {
235         case APIC_DM_LOWPRI:
236             /* XXX: search for focus processor, arbitration */
237             {
238                 int i, d;
239                 d = -1;
240                 for (i = 0; i < max_apic_words; i++) {
241                     if (deliver_bitmask[i]) {
242                         d = i * 32 + apic_ffs_bit(deliver_bitmask[i]);
243                         break;
244                     }
245                 }
246                 if (d >= 0) {
247                     apic_iter = local_apics[d];
248                     if (apic_iter) {
249                         apic_set_irq(apic_iter, vector_num, trigger_mode);
250                     }
251                 }
252             }
253             return;
254 
255         case APIC_DM_FIXED:
256             break;
257 
258         case APIC_DM_SMI:
259             foreach_apic(apic_iter, deliver_bitmask,
260                 cpu_interrupt(CPU(apic_iter->cpu), CPU_INTERRUPT_SMI)
261             );
262             return;
263 
264         case APIC_DM_NMI:
265             foreach_apic(apic_iter, deliver_bitmask,
266                 cpu_interrupt(CPU(apic_iter->cpu), CPU_INTERRUPT_NMI)
267             );
268             return;
269 
270         case APIC_DM_INIT:
271             /* normal INIT IPI sent to processors */
272             foreach_apic(apic_iter, deliver_bitmask,
273                          cpu_interrupt(CPU(apic_iter->cpu),
274                                        CPU_INTERRUPT_INIT)
275             );
276             return;
277 
278         case APIC_DM_EXTINT:
279             /* handled in I/O APIC code */
280             break;
281 
282         default:
283             return;
284     }
285 
286     foreach_apic(apic_iter, deliver_bitmask,
287                  apic_set_irq(apic_iter, vector_num, trigger_mode) );
288 }
289 
apic_deliver_irq(uint32_t dest,uint8_t dest_mode,uint8_t delivery_mode,uint8_t vector_num,uint8_t trigger_mode)290 static void apic_deliver_irq(uint32_t dest, uint8_t dest_mode,
291                              uint8_t delivery_mode, uint8_t vector_num,
292                              uint8_t trigger_mode)
293 {
294     g_autofree uint32_t *deliver_bitmask = g_new(uint32_t, max_apic_words);
295 
296     trace_apic_deliver_irq(dest, dest_mode, delivery_mode, vector_num,
297                            trigger_mode);
298 
299     apic_get_delivery_bitmask(deliver_bitmask, dest, dest_mode);
300     apic_bus_deliver(deliver_bitmask, delivery_mode, vector_num, trigger_mode);
301 }
302 
is_x2apic_mode(DeviceState * dev)303 bool is_x2apic_mode(DeviceState *dev)
304 {
305     APICCommonState *s = APIC(dev);
306 
307     return s->apicbase & MSR_IA32_APICBASE_EXTD;
308 }
309 
apic_set_base_check(APICCommonState * s,uint64_t val)310 static int apic_set_base_check(APICCommonState *s, uint64_t val)
311 {
312     /* Enable x2apic when x2apic is not supported by CPU */
313     if (!cpu_has_x2apic_feature(&s->cpu->env) &&
314         val & MSR_IA32_APICBASE_EXTD) {
315         return -1;
316     }
317 
318     /*
319      * Transition into invalid state
320      * (s->apicbase & MSR_IA32_APICBASE_ENABLE == 0) &&
321      * (s->apicbase & MSR_IA32_APICBASE_EXTD) == 1
322      */
323     if (!(val & MSR_IA32_APICBASE_ENABLE) &&
324         (val & MSR_IA32_APICBASE_EXTD)) {
325         return -1;
326     }
327 
328     /* Invalid transition from disabled mode to x2APIC */
329     if (!(s->apicbase & MSR_IA32_APICBASE_ENABLE) &&
330         !(s->apicbase & MSR_IA32_APICBASE_EXTD) &&
331         (val & MSR_IA32_APICBASE_ENABLE) &&
332         (val & MSR_IA32_APICBASE_EXTD)) {
333         return -1;
334     }
335 
336     /* Invalid transition from x2APIC to xAPIC */
337     if ((s->apicbase & MSR_IA32_APICBASE_ENABLE) &&
338         (s->apicbase & MSR_IA32_APICBASE_EXTD) &&
339         (val & MSR_IA32_APICBASE_ENABLE) &&
340         !(val & MSR_IA32_APICBASE_EXTD)) {
341         return -1;
342     }
343 
344     return 0;
345 }
346 
apic_set_base(APICCommonState * s,uint64_t val)347 static int apic_set_base(APICCommonState *s, uint64_t val)
348 {
349     if (apic_set_base_check(s, val) < 0) {
350         return -1;
351     }
352 
353     s->apicbase = (val & MSR_IA32_APICBASE_BASE) |
354         (s->apicbase & (MSR_IA32_APICBASE_BSP | MSR_IA32_APICBASE_ENABLE));
355     if (!(val & MSR_IA32_APICBASE_ENABLE)) {
356         s->apicbase &= ~MSR_IA32_APICBASE_ENABLE;
357         cpu_clear_apic_feature(&s->cpu->env);
358         s->spurious_vec &= ~APIC_SV_ENABLE;
359     }
360 
361     /* Transition from disabled mode to xAPIC */
362     if (!(s->apicbase & MSR_IA32_APICBASE_ENABLE) &&
363         (val & MSR_IA32_APICBASE_ENABLE)) {
364         s->apicbase |= MSR_IA32_APICBASE_ENABLE;
365         cpu_set_apic_feature(&s->cpu->env);
366     }
367 
368     /* Transition from xAPIC to x2APIC */
369     if (cpu_has_x2apic_feature(&s->cpu->env) &&
370         !(s->apicbase & MSR_IA32_APICBASE_EXTD) &&
371         (val & MSR_IA32_APICBASE_EXTD)) {
372         s->apicbase |= MSR_IA32_APICBASE_EXTD;
373 
374         s->log_dest = ((s->initial_apic_id & 0xffff0) << 16) |
375                       (1 << (s->initial_apic_id & 0xf));
376     }
377 
378     return 0;
379 }
380 
apic_set_tpr(APICCommonState * s,uint8_t val)381 static void apic_set_tpr(APICCommonState *s, uint8_t val)
382 {
383     /* Updates from cr8 are ignored while the VAPIC is active */
384     if (!s->vapic_paddr) {
385         s->tpr = val << 4;
386         apic_update_irq(s);
387     }
388 }
389 
apic_get_highest_priority_irr(DeviceState * dev)390 int apic_get_highest_priority_irr(DeviceState *dev)
391 {
392     APICCommonState *s;
393 
394     if (!dev) {
395         /* no interrupts */
396         return -1;
397     }
398     s = APIC_COMMON(dev);
399     return get_highest_priority_int(s->irr);
400 }
401 
apic_get_tpr(APICCommonState * s)402 static uint8_t apic_get_tpr(APICCommonState *s)
403 {
404     apic_sync_vapic(s, SYNC_FROM_VAPIC);
405     return s->tpr >> 4;
406 }
407 
apic_get_ppr(APICCommonState * s)408 int apic_get_ppr(APICCommonState *s)
409 {
410     int tpr, isrv, ppr;
411 
412     tpr = (s->tpr >> 4);
413     isrv = get_highest_priority_int(s->isr);
414     if (isrv < 0)
415         isrv = 0;
416     isrv >>= 4;
417     if (tpr >= isrv)
418         ppr = s->tpr;
419     else
420         ppr = isrv << 4;
421     return ppr;
422 }
423 
apic_get_arb_pri(APICCommonState * s)424 static int apic_get_arb_pri(APICCommonState *s)
425 {
426     /* XXX: arbitration */
427     return 0;
428 }
429 
430 
431 /*
432  * <0 - low prio interrupt,
433  * 0  - no interrupt,
434  * >0 - interrupt number
435  */
apic_irq_pending(APICCommonState * s)436 static int apic_irq_pending(APICCommonState *s)
437 {
438     int irrv, ppr;
439 
440     if (!(s->spurious_vec & APIC_SV_ENABLE)) {
441         return 0;
442     }
443 
444     irrv = get_highest_priority_int(s->irr);
445     if (irrv < 0) {
446         return 0;
447     }
448     ppr = apic_get_ppr(s);
449     if (ppr && (irrv & 0xf0) <= (ppr & 0xf0)) {
450         return -1;
451     }
452 
453     return irrv;
454 }
455 
456 /* signal the CPU if an irq is pending */
apic_update_irq(APICCommonState * s)457 static void apic_update_irq(APICCommonState *s)
458 {
459     CPUState *cpu;
460     DeviceState *dev = (DeviceState *)s;
461 
462     cpu = CPU(s->cpu);
463     if (!qemu_cpu_is_self(cpu)) {
464         cpu_interrupt(cpu, CPU_INTERRUPT_POLL);
465     } else if (apic_irq_pending(s) > 0) {
466         cpu_interrupt(cpu, CPU_INTERRUPT_HARD);
467     } else if (!apic_accept_pic_intr(dev) || !pic_get_output(isa_pic)) {
468         cpu_reset_interrupt(cpu, CPU_INTERRUPT_HARD);
469     }
470 }
471 
apic_poll_irq(DeviceState * dev)472 void apic_poll_irq(DeviceState *dev)
473 {
474     APICCommonState *s = APIC(dev);
475 
476     apic_sync_vapic(s, SYNC_FROM_VAPIC);
477     apic_update_irq(s);
478 }
479 
apic_set_irq(APICCommonState * s,int vector_num,int trigger_mode)480 static void apic_set_irq(APICCommonState *s, int vector_num, int trigger_mode)
481 {
482     kvm_report_irq_delivered(!apic_get_bit(s->irr, vector_num));
483 
484     apic_set_bit(s->irr, vector_num);
485     if (trigger_mode)
486         apic_set_bit(s->tmr, vector_num);
487     else
488         apic_reset_bit(s->tmr, vector_num);
489     if (s->vapic_paddr) {
490         apic_sync_vapic(s, SYNC_ISR_IRR_TO_VAPIC);
491         /*
492          * The vcpu thread needs to see the new IRR before we pull its current
493          * TPR value. That way, if we miss a lowering of the TRP, the guest
494          * has the chance to notice the new IRR and poll for IRQs on its own.
495          */
496         smp_wmb();
497         apic_sync_vapic(s, SYNC_FROM_VAPIC);
498     }
499     apic_update_irq(s);
500 }
501 
apic_eoi(APICCommonState * s)502 static void apic_eoi(APICCommonState *s)
503 {
504     int isrv;
505     isrv = get_highest_priority_int(s->isr);
506     if (isrv < 0)
507         return;
508     apic_reset_bit(s->isr, isrv);
509     if (!(s->spurious_vec & APIC_SV_DIRECTED_IO) && apic_get_bit(s->tmr, isrv)) {
510         ioapic_eoi_broadcast(isrv);
511     }
512     apic_sync_vapic(s, SYNC_FROM_VAPIC | SYNC_TO_VAPIC);
513     apic_update_irq(s);
514 }
515 
apic_match_dest(APICCommonState * apic,uint32_t dest)516 static bool apic_match_dest(APICCommonState *apic, uint32_t dest)
517 {
518     if (is_x2apic_mode(&apic->parent_obj)) {
519         return apic->initial_apic_id == dest;
520     } else {
521         return apic->id == (uint8_t)dest;
522     }
523 }
524 
apic_find_dest(uint32_t * deliver_bitmask,uint32_t dest)525 static void apic_find_dest(uint32_t *deliver_bitmask, uint32_t dest)
526 {
527     APICCommonState *apic = NULL;
528     int i;
529 
530     for (i = 0; i < max_apics; i++) {
531         apic = local_apics[i];
532         if (apic && apic_match_dest(apic, dest)) {
533             apic_set_bit(deliver_bitmask, i);
534         }
535     }
536 }
537 
538 /*
539  * Deliver interrupt to x2APIC CPUs if it is x2APIC broadcast.
540  * Otherwise, deliver interrupt to xAPIC CPUs if it is xAPIC
541  * broadcast.
542  */
apic_get_broadcast_bitmask(uint32_t * deliver_bitmask,bool is_x2apic_broadcast)543 static void apic_get_broadcast_bitmask(uint32_t *deliver_bitmask,
544                                        bool is_x2apic_broadcast)
545 {
546     int i;
547     APICCommonState *apic_iter;
548 
549     for (i = 0; i < max_apics; i++) {
550         apic_iter = local_apics[i];
551         if (apic_iter) {
552             bool apic_in_x2apic = is_x2apic_mode(&apic_iter->parent_obj);
553 
554             if (is_x2apic_broadcast && apic_in_x2apic) {
555                 apic_set_bit(deliver_bitmask, i);
556             } else if (!is_x2apic_broadcast && !apic_in_x2apic) {
557                 apic_set_bit(deliver_bitmask, i);
558             }
559         }
560     }
561 }
562 
apic_get_delivery_bitmask(uint32_t * deliver_bitmask,uint32_t dest,uint8_t dest_mode)563 static void apic_get_delivery_bitmask(uint32_t *deliver_bitmask,
564                                       uint32_t dest, uint8_t dest_mode)
565 {
566     APICCommonState *apic;
567     int i;
568 
569     memset(deliver_bitmask, 0x00, max_apic_words * sizeof(uint32_t));
570 
571     /*
572      * x2APIC broadcast is delivered to all x2APIC CPUs regardless of
573      * destination mode. In case the destination mode is physical, it is
574      * broadcasted to all xAPIC CPUs too. Otherwise, if the destination
575      * mode is logical, we need to continue checking if xAPIC CPUs accepts
576      * the interrupt.
577      */
578     if (dest == 0xffffffff) {
579         if (dest_mode == APIC_DESTMODE_PHYSICAL) {
580             memset(deliver_bitmask, 0xff, max_apic_words * sizeof(uint32_t));
581             return;
582         } else {
583             apic_get_broadcast_bitmask(deliver_bitmask, true);
584         }
585     }
586 
587     if (dest_mode == APIC_DESTMODE_PHYSICAL) {
588         apic_find_dest(deliver_bitmask, dest);
589         /* Any APIC in xAPIC mode will interpret 0xFF as broadcast */
590         if (dest == 0xff) {
591             apic_get_broadcast_bitmask(deliver_bitmask, false);
592         }
593     } else {
594         /* XXX: logical mode */
595         for (i = 0; i < max_apics; i++) {
596             apic = local_apics[i];
597             if (apic) {
598                 /* x2APIC logical mode */
599                 if (apic->apicbase & MSR_IA32_APICBASE_EXTD) {
600                     if ((dest >> 16) == (apic->extended_log_dest >> 16) &&
601                         (dest & apic->extended_log_dest & 0xffff)) {
602                         apic_set_bit(deliver_bitmask, i);
603                     }
604                     continue;
605                 }
606 
607                 /* xAPIC logical mode */
608                 dest = (uint8_t)dest;
609                 if (apic->dest_mode == APIC_DESTMODE_LOGICAL_FLAT) {
610                     if (dest & apic->log_dest) {
611                         apic_set_bit(deliver_bitmask, i);
612                     }
613                 } else if (apic->dest_mode == APIC_DESTMODE_LOGICAL_CLUSTER) {
614                     /*
615                      * In cluster model of xAPIC logical mode IPI, 4 higher
616                      * bits are used as cluster address, 4 lower bits are
617                      * the bitmask for local APICs in the cluster. The IPI
618                      * is delivered to an APIC if the cluster address
619                      * matches and the APIC's address bit in the cluster is
620                      * set in bitmask of destination ID in IPI.
621                      *
622                      * The cluster address ranges from 0 - 14, the cluster
623                      * address 15 (0xf) is the broadcast address to all
624                      * clusters.
625                      */
626                     if ((dest & 0xf0) == 0xf0 ||
627                         (dest & 0xf0) == (apic->log_dest & 0xf0)) {
628                         if (dest & apic->log_dest & 0x0f) {
629                             apic_set_bit(deliver_bitmask, i);
630                         }
631                     }
632                }
633             }
634         }
635     }
636 }
637 
apic_startup(APICCommonState * s,int vector_num)638 static void apic_startup(APICCommonState *s, int vector_num)
639 {
640     s->sipi_vector = vector_num;
641     cpu_interrupt(CPU(s->cpu), CPU_INTERRUPT_SIPI);
642 }
643 
apic_sipi(DeviceState * dev)644 void apic_sipi(DeviceState *dev)
645 {
646     APICCommonState *s = APIC(dev);
647 
648     if (!s->wait_for_sipi)
649         return;
650     cpu_x86_load_seg_cache_sipi(s->cpu, s->sipi_vector);
651     s->wait_for_sipi = 0;
652 }
653 
apic_deliver(DeviceState * dev,uint32_t dest,uint8_t dest_mode,uint8_t delivery_mode,uint8_t vector_num,uint8_t trigger_mode,uint8_t dest_shorthand)654 static void apic_deliver(DeviceState *dev, uint32_t dest, uint8_t dest_mode,
655                          uint8_t delivery_mode, uint8_t vector_num,
656                          uint8_t trigger_mode, uint8_t dest_shorthand)
657 {
658     APICCommonState *s = APIC(dev);
659     APICCommonState *apic_iter;
660     uint32_t deliver_bitmask_size = max_apic_words * sizeof(uint32_t);
661     g_autofree uint32_t *deliver_bitmask = g_new(uint32_t, max_apic_words);
662     uint32_t current_apic_id;
663 
664     if (is_x2apic_mode(dev)) {
665         current_apic_id = s->initial_apic_id;
666     } else {
667         current_apic_id = s->id;
668     }
669 
670     switch (dest_shorthand) {
671     case 0:
672         apic_get_delivery_bitmask(deliver_bitmask, dest, dest_mode);
673         break;
674     case 1:
675         memset(deliver_bitmask, 0x00, deliver_bitmask_size);
676         apic_set_bit(deliver_bitmask, current_apic_id);
677         break;
678     case 2:
679         memset(deliver_bitmask, 0xff, deliver_bitmask_size);
680         break;
681     case 3:
682         memset(deliver_bitmask, 0xff, deliver_bitmask_size);
683         apic_reset_bit(deliver_bitmask, current_apic_id);
684         break;
685     }
686 
687     switch (delivery_mode) {
688         case APIC_DM_INIT:
689             {
690                 int trig_mode = (s->icr[0] >> 15) & 1;
691                 int level = (s->icr[0] >> 14) & 1;
692                 if (level == 0 && trig_mode == 1) {
693                     foreach_apic(apic_iter, deliver_bitmask,
694                                  apic_iter->arb_id = apic_iter->id );
695                     return;
696                 }
697             }
698             break;
699 
700         case APIC_DM_SIPI:
701             foreach_apic(apic_iter, deliver_bitmask,
702                          apic_startup(apic_iter, vector_num) );
703             return;
704     }
705 
706     apic_bus_deliver(deliver_bitmask, delivery_mode, vector_num, trigger_mode);
707 }
708 
apic_check_pic(APICCommonState * s)709 static bool apic_check_pic(APICCommonState *s)
710 {
711     DeviceState *dev = (DeviceState *)s;
712 
713     if (!apic_accept_pic_intr(dev) || !pic_get_output(isa_pic)) {
714         return false;
715     }
716     apic_deliver_pic_intr(dev, 1);
717     return true;
718 }
719 
apic_get_interrupt(DeviceState * dev)720 int apic_get_interrupt(DeviceState *dev)
721 {
722     APICCommonState *s = APIC(dev);
723     int intno;
724 
725     /* if the APIC is installed or enabled, we let the 8259 handle the
726        IRQs */
727     if (!s)
728         return -1;
729     if (!(s->spurious_vec & APIC_SV_ENABLE))
730         return -1;
731 
732     apic_sync_vapic(s, SYNC_FROM_VAPIC);
733     intno = apic_irq_pending(s);
734 
735     /* if there is an interrupt from the 8259, let the caller handle
736      * that first since ExtINT interrupts ignore the priority.
737      */
738     if (intno == 0 || apic_check_pic(s)) {
739         apic_sync_vapic(s, SYNC_TO_VAPIC);
740         return -1;
741     } else if (intno < 0) {
742         apic_sync_vapic(s, SYNC_TO_VAPIC);
743         return s->spurious_vec & 0xff;
744     }
745     apic_reset_bit(s->irr, intno);
746     apic_set_bit(s->isr, intno);
747     apic_sync_vapic(s, SYNC_TO_VAPIC);
748 
749     apic_update_irq(s);
750 
751     return intno;
752 }
753 
apic_accept_pic_intr(DeviceState * dev)754 int apic_accept_pic_intr(DeviceState *dev)
755 {
756     APICCommonState *s = APIC(dev);
757     uint32_t lvt0;
758 
759     if (!s)
760         return -1;
761 
762     lvt0 = s->lvt[APIC_LVT_LINT0];
763 
764     if ((s->apicbase & MSR_IA32_APICBASE_ENABLE) == 0 ||
765         (lvt0 & APIC_LVT_MASKED) == 0)
766         return isa_pic != NULL;
767 
768     return 0;
769 }
770 
apic_timer_update(APICCommonState * s,int64_t current_time)771 static void apic_timer_update(APICCommonState *s, int64_t current_time)
772 {
773     if (apic_next_timer(s, current_time)) {
774         timer_mod(s->timer, s->next_time);
775     } else {
776         timer_del(s->timer);
777     }
778 }
779 
apic_timer(void * opaque)780 static void apic_timer(void *opaque)
781 {
782     APICCommonState *s = opaque;
783 
784     apic_local_deliver(s, APIC_LVT_TIMER);
785     apic_timer_update(s, s->next_time);
786 }
787 
apic_register_read(int index,uint64_t * value)788 static int apic_register_read(int index, uint64_t *value)
789 {
790     DeviceState *dev;
791     APICCommonState *s;
792     uint32_t val;
793     int ret = 0;
794 
795     dev = cpu_get_current_apic();
796     if (!dev) {
797         return -1;
798     }
799     s = APIC(dev);
800 
801     switch(index) {
802     case 0x02: /* id */
803         if (is_x2apic_mode(dev)) {
804             val = s->initial_apic_id;
805         } else {
806             val = s->id << 24;
807         }
808         break;
809     case 0x03: /* version */
810         val = s->version | ((APIC_LVT_NB - 1) << 16);
811         break;
812     case 0x08:
813         apic_sync_vapic(s, SYNC_FROM_VAPIC);
814         if (apic_report_tpr_access) {
815             cpu_report_tpr_access(&s->cpu->env, TPR_ACCESS_READ);
816         }
817         val = s->tpr;
818         break;
819     case 0x09:
820         val = apic_get_arb_pri(s);
821         break;
822     case 0x0a:
823         /* ppr */
824         val = apic_get_ppr(s);
825         break;
826     case 0x0b:
827         val = 0;
828         break;
829     case 0x0d:
830         if (is_x2apic_mode(dev)) {
831             val = s->extended_log_dest;
832         } else {
833             val = s->log_dest << 24;
834         }
835         break;
836     case 0x0e:
837         if (is_x2apic_mode(dev)) {
838             val = 0;
839             ret = -1;
840         } else {
841             val = (s->dest_mode << 28) | 0xfffffff;
842         }
843         break;
844     case 0x0f:
845         val = s->spurious_vec;
846         break;
847     case 0x10 ... 0x17:
848         val = s->isr[index & 7];
849         break;
850     case 0x18 ... 0x1f:
851         val = s->tmr[index & 7];
852         break;
853     case 0x20 ... 0x27:
854         val = s->irr[index & 7];
855         break;
856     case 0x28:
857         val = s->esr;
858         break;
859     case 0x30:
860     case 0x31:
861         val = s->icr[index & 1];
862         break;
863     case 0x32 ... 0x37:
864         val = s->lvt[index - 0x32];
865         break;
866     case 0x38:
867         val = s->initial_count;
868         break;
869     case 0x39:
870         val = apic_get_current_count(s);
871         break;
872     case 0x3e:
873         val = s->divide_conf;
874         break;
875     default:
876         s->esr |= APIC_ESR_ILLEGAL_ADDRESS;
877         val = 0;
878         ret = -1;
879         break;
880     }
881 
882     trace_apic_register_read(index, val);
883     *value = val;
884     return ret;
885 }
886 
apic_mem_read(void * opaque,hwaddr addr,unsigned size)887 static uint64_t apic_mem_read(void *opaque, hwaddr addr, unsigned size)
888 {
889     uint64_t val;
890     int index;
891 
892     if (size < 4) {
893         return 0;
894     }
895 
896     index = (addr >> 4) & 0xff;
897     apic_register_read(index, &val);
898 
899     return val;
900 }
901 
apic_msr_read(int index,uint64_t * val)902 int apic_msr_read(int index, uint64_t *val)
903 {
904     DeviceState *dev;
905 
906     dev = cpu_get_current_apic();
907     if (!dev) {
908         return -1;
909     }
910 
911     if (!is_x2apic_mode(dev)) {
912         return -1;
913     }
914 
915     return apic_register_read(index, val);
916 }
917 
apic_send_msi(MSIMessage * msi)918 static void apic_send_msi(MSIMessage *msi)
919 {
920     uint64_t addr = msi->address;
921     uint32_t data = msi->data;
922     uint32_t dest = (addr & MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
923     /*
924      * The higher 3 bytes of destination id is stored in higher word of
925      * msi address. See x86_iommu_irq_to_msi_message()
926      */
927     dest = dest | (addr >> 32);
928     uint8_t vector = (data & MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
929     uint8_t dest_mode = (addr >> MSI_ADDR_DEST_MODE_SHIFT) & 0x1;
930     uint8_t trigger_mode = (data >> MSI_DATA_TRIGGER_SHIFT) & 0x1;
931     uint8_t delivery = (data >> MSI_DATA_DELIVERY_MODE_SHIFT) & 0x7;
932     /* XXX: Ignore redirection hint. */
933     apic_deliver_irq(dest, dest_mode, delivery, vector, trigger_mode);
934 }
935 
apic_register_write(int index,uint64_t val)936 static int apic_register_write(int index, uint64_t val)
937 {
938     DeviceState *dev;
939     APICCommonState *s;
940 
941     dev = cpu_get_current_apic();
942     if (!dev) {
943         return -1;
944     }
945     s = APIC(dev);
946 
947     trace_apic_register_write(index, val);
948 
949     switch(index) {
950     case 0x02:
951         if (is_x2apic_mode(dev)) {
952             return -1;
953         }
954 
955         s->id = (val >> 24);
956         break;
957     case 0x03:
958         break;
959     case 0x08:
960         if (apic_report_tpr_access) {
961             cpu_report_tpr_access(&s->cpu->env, TPR_ACCESS_WRITE);
962         }
963         s->tpr = val;
964         apic_sync_vapic(s, SYNC_TO_VAPIC);
965         apic_update_irq(s);
966         break;
967     case 0x09:
968     case 0x0a:
969         break;
970     case 0x0b: /* EOI */
971         apic_eoi(s);
972         break;
973     case 0x0d:
974         if (is_x2apic_mode(dev)) {
975             return -1;
976         }
977 
978         s->log_dest = val >> 24;
979         break;
980     case 0x0e:
981         if (is_x2apic_mode(dev)) {
982             return -1;
983         }
984 
985         s->dest_mode = val >> 28;
986         break;
987     case 0x0f:
988         s->spurious_vec = val & 0x1ff;
989         apic_update_irq(s);
990         break;
991     case 0x10 ... 0x17:
992     case 0x18 ... 0x1f:
993     case 0x20 ... 0x27:
994     case 0x28:
995         break;
996     case 0x30: {
997         uint32_t dest;
998 
999         s->icr[0] = val;
1000         if (is_x2apic_mode(dev)) {
1001             s->icr[1] = val >> 32;
1002             dest = s->icr[1];
1003         } else {
1004             dest = (s->icr[1] >> 24) & 0xff;
1005         }
1006 
1007         apic_deliver(dev, dest, (s->icr[0] >> 11) & 1,
1008                      (s->icr[0] >> 8) & 7, (s->icr[0] & 0xff),
1009                      (s->icr[0] >> 15) & 1, (s->icr[0] >> 18) & 3);
1010         break;
1011     }
1012     case 0x31:
1013         if (is_x2apic_mode(dev)) {
1014             return -1;
1015         }
1016 
1017         s->icr[1] = val;
1018         break;
1019     case 0x32 ... 0x37:
1020         {
1021             int n = index - 0x32;
1022             s->lvt[n] = val;
1023             if (n == APIC_LVT_TIMER) {
1024                 apic_timer_update(s, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
1025             } else if (n == APIC_LVT_LINT0 && apic_check_pic(s)) {
1026                 apic_update_irq(s);
1027             }
1028         }
1029         break;
1030     case 0x38:
1031         s->initial_count = val;
1032         s->initial_count_load_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
1033         apic_timer_update(s, s->initial_count_load_time);
1034         break;
1035     case 0x39:
1036         break;
1037     case 0x3e:
1038         {
1039             int v;
1040             s->divide_conf = val & 0xb;
1041             v = (s->divide_conf & 3) | ((s->divide_conf >> 1) & 4);
1042             s->count_shift = (v + 1) & 7;
1043         }
1044         break;
1045     case 0x3f: {
1046         int vector = val & 0xff;
1047 
1048         if (!is_x2apic_mode(dev)) {
1049             return -1;
1050         }
1051 
1052         /*
1053          * Self IPI is identical to IPI with
1054          * - Destination shorthand: 1 (Self)
1055          * - Trigger mode: 0 (Edge)
1056          * - Delivery mode: 0 (Fixed)
1057          */
1058         apic_deliver(dev, 0, 0, APIC_DM_FIXED, vector, 0, 1);
1059 
1060         break;
1061     }
1062     default:
1063         s->esr |= APIC_ESR_ILLEGAL_ADDRESS;
1064         return -1;
1065     }
1066 
1067     return 0;
1068 }
1069 
apic_mem_write(void * opaque,hwaddr addr,uint64_t val,unsigned size)1070 static void apic_mem_write(void *opaque, hwaddr addr, uint64_t val,
1071                            unsigned size)
1072 {
1073     int index = (addr >> 4) & 0xff;
1074 
1075     if (size < 4) {
1076         return;
1077     }
1078 
1079     if (addr > 0xfff || !index) {
1080         /*
1081          * MSI and MMIO APIC are at the same memory location,
1082          * but actually not on the global bus: MSI is on PCI bus
1083          * APIC is connected directly to the CPU.
1084          * Mapping them on the global bus happens to work because
1085          * MSI registers are reserved in APIC MMIO and vice versa.
1086          */
1087         MSIMessage msi = { .address = addr, .data = val };
1088         apic_send_msi(&msi);
1089         return;
1090     }
1091 
1092     apic_register_write(index, val);
1093 }
1094 
apic_msr_write(int index,uint64_t val)1095 int apic_msr_write(int index, uint64_t val)
1096 {
1097     DeviceState *dev;
1098 
1099     dev = cpu_get_current_apic();
1100     if (!dev) {
1101         return -1;
1102     }
1103 
1104     if (!is_x2apic_mode(dev)) {
1105         return -1;
1106     }
1107 
1108     return apic_register_write(index, val);
1109 }
1110 
apic_pre_save(APICCommonState * s)1111 static void apic_pre_save(APICCommonState *s)
1112 {
1113     apic_sync_vapic(s, SYNC_FROM_VAPIC);
1114 }
1115 
apic_post_load(APICCommonState * s)1116 static void apic_post_load(APICCommonState *s)
1117 {
1118     if (s->timer_expiry != -1) {
1119         timer_mod(s->timer, s->timer_expiry);
1120     } else {
1121         timer_del(s->timer);
1122     }
1123 }
1124 
1125 static const MemoryRegionOps apic_io_ops = {
1126     .read = apic_mem_read,
1127     .write = apic_mem_write,
1128     .impl.min_access_size = 1,
1129     .impl.max_access_size = 4,
1130     .valid.min_access_size = 1,
1131     .valid.max_access_size = 4,
1132     .endianness = DEVICE_NATIVE_ENDIAN,
1133 };
1134 
apic_realize(DeviceState * dev,Error ** errp)1135 static void apic_realize(DeviceState *dev, Error **errp)
1136 {
1137     APICCommonState *s = APIC(dev);
1138 
1139     if (kvm_enabled()) {
1140         warn_report("Userspace local APIC is deprecated for KVM.");
1141         warn_report("Do not use kernel-irqchip except for the -M isapc machine type.");
1142     }
1143 
1144     memory_region_init_io(&s->io_memory, OBJECT(s), &apic_io_ops, s, "apic-msi",
1145                           APIC_SPACE_SIZE);
1146 
1147     /*
1148      * apic-msi's apic_mem_write can call into ioapic_eoi_broadcast, which can
1149      * write back to apic-msi. As such mark the apic-msi region re-entrancy
1150      * safe.
1151      */
1152     s->io_memory.disable_reentrancy_guard = true;
1153 
1154     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, apic_timer, s);
1155 
1156     /*
1157      * The --machine none does not call apic_set_max_apic_id before creating
1158      * apic, so we need to call it here and set it to 1 which is the max cpus
1159      * in machine none.
1160      */
1161     if (!local_apics) {
1162         apic_set_max_apic_id(1);
1163     }
1164     local_apics[s->initial_apic_id] = s;
1165 
1166     msi_nonbroken = true;
1167 }
1168 
apic_unrealize(DeviceState * dev)1169 static void apic_unrealize(DeviceState *dev)
1170 {
1171     APICCommonState *s = APIC(dev);
1172 
1173     timer_free(s->timer);
1174     local_apics[s->initial_apic_id] = NULL;
1175 }
1176 
apic_class_init(ObjectClass * klass,const void * data)1177 static void apic_class_init(ObjectClass *klass, const void *data)
1178 {
1179     APICCommonClass *k = APIC_COMMON_CLASS(klass);
1180 
1181     k->realize = apic_realize;
1182     k->unrealize = apic_unrealize;
1183     k->set_base = apic_set_base;
1184     k->set_tpr = apic_set_tpr;
1185     k->get_tpr = apic_get_tpr;
1186     k->vapic_base_update = apic_vapic_base_update;
1187     k->external_nmi = apic_external_nmi;
1188     k->pre_save = apic_pre_save;
1189     k->post_load = apic_post_load;
1190     k->send_msi = apic_send_msi;
1191 }
1192 
1193 static const TypeInfo apic_info = {
1194     .name          = TYPE_APIC,
1195     .instance_size = sizeof(APICCommonState),
1196     .parent        = TYPE_APIC_COMMON,
1197     .class_init    = apic_class_init,
1198 };
1199 
apic_register_types(void)1200 static void apic_register_types(void)
1201 {
1202     type_register_static(&apic_info);
1203 }
1204 
1205 type_init(apic_register_types)
1206