xref: /openbmc/qemu/hw/intc/arm_gic.c (revision a9d853533cc1a27dc09b10c7ab89677f9c5dd8f4)
1 /*
2  * ARM Generic/Distributed Interrupt Controller
3  *
4  * Copyright (c) 2006-2007 CodeSourcery.
5  * Written by Paul Brook
6  *
7  * This code is licensed under the GPL.
8  */
9 
10 /* This file contains implementation code for the RealView EB interrupt
11  * controller, MPCore distributed interrupt controller and ARMv7-M
12  * Nested Vectored Interrupt Controller.
13  * It is compiled in two ways:
14  *  (1) as a standalone file to produce a sysbus device which is a GIC
15  *  that can be used on the realview board and as one of the builtin
16  *  private peripherals for the ARM MP CPUs (11MPCore, A9, etc)
17  *  (2) by being directly #included into armv7m_nvic.c to produce the
18  *  armv7m_nvic device.
19  */
20 
21 #include "hw/sysbus.h"
22 #include "gic_internal.h"
23 #include "qom/cpu.h"
24 
25 //#define DEBUG_GIC
26 
27 #ifdef DEBUG_GIC
28 #define DPRINTF(fmt, ...) \
29 do { fprintf(stderr, "arm_gic: " fmt , ## __VA_ARGS__); } while (0)
30 #else
31 #define DPRINTF(fmt, ...) do {} while(0)
32 #endif
33 
34 static const uint8_t gic_id[] = {
35     0x90, 0x13, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1
36 };
37 
38 #define NUM_CPU(s) ((s)->num_cpu)
39 
40 static inline int gic_get_current_cpu(GICState *s)
41 {
42     if (s->num_cpu > 1) {
43         return current_cpu->cpu_index;
44     }
45     return 0;
46 }
47 
48 /* TODO: Many places that call this routine could be optimized.  */
49 /* Update interrupt status after enabled or pending bits have been changed.  */
50 void gic_update(GICState *s)
51 {
52     int best_irq;
53     int best_prio;
54     int irq;
55     int level;
56     int cpu;
57     int cm;
58 
59     for (cpu = 0; cpu < NUM_CPU(s); cpu++) {
60         cm = 1 << cpu;
61         s->current_pending[cpu] = 1023;
62         if (!s->enabled || !s->cpu_enabled[cpu]) {
63             qemu_irq_lower(s->parent_irq[cpu]);
64             return;
65         }
66         best_prio = 0x100;
67         best_irq = 1023;
68         for (irq = 0; irq < s->num_irq; irq++) {
69             if (GIC_TEST_ENABLED(irq, cm) && gic_test_pending(s, irq, cm) &&
70                 (irq < GIC_INTERNAL || GIC_TARGET(irq) & cm)) {
71                 if (GIC_GET_PRIORITY(irq, cpu) < best_prio) {
72                     best_prio = GIC_GET_PRIORITY(irq, cpu);
73                     best_irq = irq;
74                 }
75             }
76         }
77         level = 0;
78         if (best_prio < s->priority_mask[cpu]) {
79             s->current_pending[cpu] = best_irq;
80             if (best_prio < s->running_priority[cpu]) {
81                 DPRINTF("Raised pending IRQ %d (cpu %d)\n", best_irq, cpu);
82                 level = 1;
83             }
84         }
85         qemu_set_irq(s->parent_irq[cpu], level);
86     }
87 }
88 
89 void gic_set_pending_private(GICState *s, int cpu, int irq)
90 {
91     int cm = 1 << cpu;
92 
93     if (gic_test_pending(s, irq, cm)) {
94         return;
95     }
96 
97     DPRINTF("Set %d pending cpu %d\n", irq, cpu);
98     GIC_SET_PENDING(irq, cm);
99     gic_update(s);
100 }
101 
102 static void gic_set_irq_11mpcore(GICState *s, int irq, int level,
103                                  int cm, int target)
104 {
105     if (level) {
106         GIC_SET_LEVEL(irq, cm);
107         if (GIC_TEST_EDGE_TRIGGER(irq) || GIC_TEST_ENABLED(irq, cm)) {
108             DPRINTF("Set %d pending mask %x\n", irq, target);
109             GIC_SET_PENDING(irq, target);
110         }
111     } else {
112         GIC_CLEAR_LEVEL(irq, cm);
113     }
114 }
115 
116 static void gic_set_irq_generic(GICState *s, int irq, int level,
117                                 int cm, int target)
118 {
119     if (level) {
120         GIC_SET_LEVEL(irq, cm);
121         DPRINTF("Set %d pending mask %x\n", irq, target);
122         if (GIC_TEST_EDGE_TRIGGER(irq)) {
123             GIC_SET_PENDING(irq, target);
124         }
125     } else {
126         GIC_CLEAR_LEVEL(irq, cm);
127     }
128 }
129 
130 /* Process a change in an external IRQ input.  */
131 static void gic_set_irq(void *opaque, int irq, int level)
132 {
133     /* Meaning of the 'irq' parameter:
134      *  [0..N-1] : external interrupts
135      *  [N..N+31] : PPI (internal) interrupts for CPU 0
136      *  [N+32..N+63] : PPI (internal interrupts for CPU 1
137      *  ...
138      */
139     GICState *s = (GICState *)opaque;
140     int cm, target;
141     if (irq < (s->num_irq - GIC_INTERNAL)) {
142         /* The first external input line is internal interrupt 32.  */
143         cm = ALL_CPU_MASK;
144         irq += GIC_INTERNAL;
145         target = GIC_TARGET(irq);
146     } else {
147         int cpu;
148         irq -= (s->num_irq - GIC_INTERNAL);
149         cpu = irq / GIC_INTERNAL;
150         irq %= GIC_INTERNAL;
151         cm = 1 << cpu;
152         target = cm;
153     }
154 
155     assert(irq >= GIC_NR_SGIS);
156 
157     if (level == GIC_TEST_LEVEL(irq, cm)) {
158         return;
159     }
160 
161     if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {
162         gic_set_irq_11mpcore(s, irq, level, cm, target);
163     } else {
164         gic_set_irq_generic(s, irq, level, cm, target);
165     }
166 
167     gic_update(s);
168 }
169 
170 static void gic_set_running_irq(GICState *s, int cpu, int irq)
171 {
172     s->running_irq[cpu] = irq;
173     if (irq == 1023) {
174         s->running_priority[cpu] = 0x100;
175     } else {
176         s->running_priority[cpu] = GIC_GET_PRIORITY(irq, cpu);
177     }
178     gic_update(s);
179 }
180 
181 uint32_t gic_acknowledge_irq(GICState *s, int cpu)
182 {
183     int ret, irq, src;
184     int cm = 1 << cpu;
185     irq = s->current_pending[cpu];
186     if (irq == 1023
187             || GIC_GET_PRIORITY(irq, cpu) >= s->running_priority[cpu]) {
188         DPRINTF("ACK no pending IRQ\n");
189         return 1023;
190     }
191     s->last_active[irq][cpu] = s->running_irq[cpu];
192 
193     if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {
194         /* Clear pending flags for both level and edge triggered interrupts.
195          * Level triggered IRQs will be reasserted once they become inactive.
196          */
197         GIC_CLEAR_PENDING(irq, GIC_TEST_MODEL(irq) ? ALL_CPU_MASK : cm);
198         ret = irq;
199     } else {
200         if (irq < GIC_NR_SGIS) {
201             /* Lookup the source CPU for the SGI and clear this in the
202              * sgi_pending map.  Return the src and clear the overall pending
203              * state on this CPU if the SGI is not pending from any CPUs.
204              */
205             assert(s->sgi_pending[irq][cpu] != 0);
206             src = ctz32(s->sgi_pending[irq][cpu]);
207             s->sgi_pending[irq][cpu] &= ~(1 << src);
208             if (s->sgi_pending[irq][cpu] == 0) {
209                 GIC_CLEAR_PENDING(irq, GIC_TEST_MODEL(irq) ? ALL_CPU_MASK : cm);
210             }
211             ret = irq | ((src & 0x7) << 10);
212         } else {
213             /* Clear pending state for both level and edge triggered
214              * interrupts. (level triggered interrupts with an active line
215              * remain pending, see gic_test_pending)
216              */
217             GIC_CLEAR_PENDING(irq, GIC_TEST_MODEL(irq) ? ALL_CPU_MASK : cm);
218             ret = irq;
219         }
220     }
221 
222     gic_set_running_irq(s, cpu, irq);
223     DPRINTF("ACK %d\n", irq);
224     return ret;
225 }
226 
227 void gic_set_priority(GICState *s, int cpu, int irq, uint8_t val)
228 {
229     if (irq < GIC_INTERNAL) {
230         s->priority1[irq][cpu] = val;
231     } else {
232         s->priority2[(irq) - GIC_INTERNAL] = val;
233     }
234 }
235 
236 void gic_complete_irq(GICState *s, int cpu, int irq)
237 {
238     int update = 0;
239     int cm = 1 << cpu;
240     DPRINTF("EOI %d\n", irq);
241     if (irq >= s->num_irq) {
242         /* This handles two cases:
243          * 1. If software writes the ID of a spurious interrupt [ie 1023]
244          * to the GICC_EOIR, the GIC ignores that write.
245          * 2. If software writes the number of a non-existent interrupt
246          * this must be a subcase of "value written does not match the last
247          * valid interrupt value read from the Interrupt Acknowledge
248          * register" and so this is UNPREDICTABLE. We choose to ignore it.
249          */
250         return;
251     }
252     if (s->running_irq[cpu] == 1023)
253         return; /* No active IRQ.  */
254 
255     if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {
256         /* Mark level triggered interrupts as pending if they are still
257            raised.  */
258         if (!GIC_TEST_EDGE_TRIGGER(irq) && GIC_TEST_ENABLED(irq, cm)
259             && GIC_TEST_LEVEL(irq, cm) && (GIC_TARGET(irq) & cm) != 0) {
260             DPRINTF("Set %d pending mask %x\n", irq, cm);
261             GIC_SET_PENDING(irq, cm);
262             update = 1;
263         }
264     }
265 
266     if (irq != s->running_irq[cpu]) {
267         /* Complete an IRQ that is not currently running.  */
268         int tmp = s->running_irq[cpu];
269         while (s->last_active[tmp][cpu] != 1023) {
270             if (s->last_active[tmp][cpu] == irq) {
271                 s->last_active[tmp][cpu] = s->last_active[irq][cpu];
272                 break;
273             }
274             tmp = s->last_active[tmp][cpu];
275         }
276         if (update) {
277             gic_update(s);
278         }
279     } else {
280         /* Complete the current running IRQ.  */
281         gic_set_running_irq(s, cpu, s->last_active[s->running_irq[cpu]][cpu]);
282     }
283 }
284 
285 static uint32_t gic_dist_readb(void *opaque, hwaddr offset, MemTxAttrs attrs)
286 {
287     GICState *s = (GICState *)opaque;
288     uint32_t res;
289     int irq;
290     int i;
291     int cpu;
292     int cm;
293     int mask;
294 
295     cpu = gic_get_current_cpu(s);
296     cm = 1 << cpu;
297     if (offset < 0x100) {
298         if (offset == 0)
299             return s->enabled;
300         if (offset == 4)
301             /* Interrupt Controller Type Register */
302             return ((s->num_irq / 32) - 1)
303                     | ((NUM_CPU(s) - 1) << 5)
304                     | (s->security_extn << 10);
305         if (offset < 0x08)
306             return 0;
307         if (offset >= 0x80) {
308             /* Interrupt Security , RAZ/WI */
309             return 0;
310         }
311         goto bad_reg;
312     } else if (offset < 0x200) {
313         /* Interrupt Set/Clear Enable.  */
314         if (offset < 0x180)
315             irq = (offset - 0x100) * 8;
316         else
317             irq = (offset - 0x180) * 8;
318         irq += GIC_BASE_IRQ;
319         if (irq >= s->num_irq)
320             goto bad_reg;
321         res = 0;
322         for (i = 0; i < 8; i++) {
323             if (GIC_TEST_ENABLED(irq + i, cm)) {
324                 res |= (1 << i);
325             }
326         }
327     } else if (offset < 0x300) {
328         /* Interrupt Set/Clear Pending.  */
329         if (offset < 0x280)
330             irq = (offset - 0x200) * 8;
331         else
332             irq = (offset - 0x280) * 8;
333         irq += GIC_BASE_IRQ;
334         if (irq >= s->num_irq)
335             goto bad_reg;
336         res = 0;
337         mask = (irq < GIC_INTERNAL) ?  cm : ALL_CPU_MASK;
338         for (i = 0; i < 8; i++) {
339             if (gic_test_pending(s, irq + i, mask)) {
340                 res |= (1 << i);
341             }
342         }
343     } else if (offset < 0x400) {
344         /* Interrupt Active.  */
345         irq = (offset - 0x300) * 8 + GIC_BASE_IRQ;
346         if (irq >= s->num_irq)
347             goto bad_reg;
348         res = 0;
349         mask = (irq < GIC_INTERNAL) ?  cm : ALL_CPU_MASK;
350         for (i = 0; i < 8; i++) {
351             if (GIC_TEST_ACTIVE(irq + i, mask)) {
352                 res |= (1 << i);
353             }
354         }
355     } else if (offset < 0x800) {
356         /* Interrupt Priority.  */
357         irq = (offset - 0x400) + GIC_BASE_IRQ;
358         if (irq >= s->num_irq)
359             goto bad_reg;
360         res = GIC_GET_PRIORITY(irq, cpu);
361     } else if (offset < 0xc00) {
362         /* Interrupt CPU Target.  */
363         if (s->num_cpu == 1 && s->revision != REV_11MPCORE) {
364             /* For uniprocessor GICs these RAZ/WI */
365             res = 0;
366         } else {
367             irq = (offset - 0x800) + GIC_BASE_IRQ;
368             if (irq >= s->num_irq) {
369                 goto bad_reg;
370             }
371             if (irq >= 29 && irq <= 31) {
372                 res = cm;
373             } else {
374                 res = GIC_TARGET(irq);
375             }
376         }
377     } else if (offset < 0xf00) {
378         /* Interrupt Configuration.  */
379         irq = (offset - 0xc00) * 4 + GIC_BASE_IRQ;
380         if (irq >= s->num_irq)
381             goto bad_reg;
382         res = 0;
383         for (i = 0; i < 4; i++) {
384             if (GIC_TEST_MODEL(irq + i))
385                 res |= (1 << (i * 2));
386             if (GIC_TEST_EDGE_TRIGGER(irq + i))
387                 res |= (2 << (i * 2));
388         }
389     } else if (offset < 0xf10) {
390         goto bad_reg;
391     } else if (offset < 0xf30) {
392         if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {
393             goto bad_reg;
394         }
395 
396         if (offset < 0xf20) {
397             /* GICD_CPENDSGIRn */
398             irq = (offset - 0xf10);
399         } else {
400             irq = (offset - 0xf20);
401             /* GICD_SPENDSGIRn */
402         }
403 
404         res = s->sgi_pending[irq][cpu];
405     } else if (offset < 0xfe0) {
406         goto bad_reg;
407     } else /* offset >= 0xfe0 */ {
408         if (offset & 3) {
409             res = 0;
410         } else {
411             res = gic_id[(offset - 0xfe0) >> 2];
412         }
413     }
414     return res;
415 bad_reg:
416     qemu_log_mask(LOG_GUEST_ERROR,
417                   "gic_dist_readb: Bad offset %x\n", (int)offset);
418     return 0;
419 }
420 
421 static MemTxResult gic_dist_read(void *opaque, hwaddr offset, uint64_t *data,
422                                  unsigned size, MemTxAttrs attrs)
423 {
424     switch (size) {
425     case 1:
426         *data = gic_dist_readb(opaque, offset, attrs);
427         return MEMTX_OK;
428     case 2:
429         *data = gic_dist_readb(opaque, offset, attrs);
430         *data |= gic_dist_readb(opaque, offset + 1, attrs) << 8;
431         return MEMTX_OK;
432     case 4:
433         *data = gic_dist_readb(opaque, offset, attrs);
434         *data |= gic_dist_readb(opaque, offset + 1, attrs) << 8;
435         *data |= gic_dist_readb(opaque, offset + 2, attrs) << 16;
436         *data |= gic_dist_readb(opaque, offset + 3, attrs) << 24;
437         return MEMTX_OK;
438     default:
439         return MEMTX_ERROR;
440     }
441 }
442 
443 static void gic_dist_writeb(void *opaque, hwaddr offset,
444                             uint32_t value, MemTxAttrs attrs)
445 {
446     GICState *s = (GICState *)opaque;
447     int irq;
448     int i;
449     int cpu;
450 
451     cpu = gic_get_current_cpu(s);
452     if (offset < 0x100) {
453         if (offset == 0) {
454             s->enabled = (value & 1);
455             DPRINTF("Distribution %sabled\n", s->enabled ? "En" : "Dis");
456         } else if (offset < 4) {
457             /* ignored.  */
458         } else if (offset >= 0x80) {
459             /* Interrupt Security Registers, RAZ/WI */
460         } else {
461             goto bad_reg;
462         }
463     } else if (offset < 0x180) {
464         /* Interrupt Set Enable.  */
465         irq = (offset - 0x100) * 8 + GIC_BASE_IRQ;
466         if (irq >= s->num_irq)
467             goto bad_reg;
468         if (irq < GIC_NR_SGIS) {
469             value = 0xff;
470         }
471 
472         for (i = 0; i < 8; i++) {
473             if (value & (1 << i)) {
474                 int mask =
475                     (irq < GIC_INTERNAL) ? (1 << cpu) : GIC_TARGET(irq + i);
476                 int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK;
477 
478                 if (!GIC_TEST_ENABLED(irq + i, cm)) {
479                     DPRINTF("Enabled IRQ %d\n", irq + i);
480                 }
481                 GIC_SET_ENABLED(irq + i, cm);
482                 /* If a raised level triggered IRQ enabled then mark
483                    is as pending.  */
484                 if (GIC_TEST_LEVEL(irq + i, mask)
485                         && !GIC_TEST_EDGE_TRIGGER(irq + i)) {
486                     DPRINTF("Set %d pending mask %x\n", irq + i, mask);
487                     GIC_SET_PENDING(irq + i, mask);
488                 }
489             }
490         }
491     } else if (offset < 0x200) {
492         /* Interrupt Clear Enable.  */
493         irq = (offset - 0x180) * 8 + GIC_BASE_IRQ;
494         if (irq >= s->num_irq)
495             goto bad_reg;
496         if (irq < GIC_NR_SGIS) {
497             value = 0;
498         }
499 
500         for (i = 0; i < 8; i++) {
501             if (value & (1 << i)) {
502                 int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK;
503 
504                 if (GIC_TEST_ENABLED(irq + i, cm)) {
505                     DPRINTF("Disabled IRQ %d\n", irq + i);
506                 }
507                 GIC_CLEAR_ENABLED(irq + i, cm);
508             }
509         }
510     } else if (offset < 0x280) {
511         /* Interrupt Set Pending.  */
512         irq = (offset - 0x200) * 8 + GIC_BASE_IRQ;
513         if (irq >= s->num_irq)
514             goto bad_reg;
515         if (irq < GIC_NR_SGIS) {
516             value = 0;
517         }
518 
519         for (i = 0; i < 8; i++) {
520             if (value & (1 << i)) {
521                 GIC_SET_PENDING(irq + i, GIC_TARGET(irq + i));
522             }
523         }
524     } else if (offset < 0x300) {
525         /* Interrupt Clear Pending.  */
526         irq = (offset - 0x280) * 8 + GIC_BASE_IRQ;
527         if (irq >= s->num_irq)
528             goto bad_reg;
529         if (irq < GIC_NR_SGIS) {
530             value = 0;
531         }
532 
533         for (i = 0; i < 8; i++) {
534             /* ??? This currently clears the pending bit for all CPUs, even
535                for per-CPU interrupts.  It's unclear whether this is the
536                corect behavior.  */
537             if (value & (1 << i)) {
538                 GIC_CLEAR_PENDING(irq + i, ALL_CPU_MASK);
539             }
540         }
541     } else if (offset < 0x400) {
542         /* Interrupt Active.  */
543         goto bad_reg;
544     } else if (offset < 0x800) {
545         /* Interrupt Priority.  */
546         irq = (offset - 0x400) + GIC_BASE_IRQ;
547         if (irq >= s->num_irq)
548             goto bad_reg;
549         gic_set_priority(s, cpu, irq, value);
550     } else if (offset < 0xc00) {
551         /* Interrupt CPU Target. RAZ/WI on uniprocessor GICs, with the
552          * annoying exception of the 11MPCore's GIC.
553          */
554         if (s->num_cpu != 1 || s->revision == REV_11MPCORE) {
555             irq = (offset - 0x800) + GIC_BASE_IRQ;
556             if (irq >= s->num_irq) {
557                 goto bad_reg;
558             }
559             if (irq < 29) {
560                 value = 0;
561             } else if (irq < GIC_INTERNAL) {
562                 value = ALL_CPU_MASK;
563             }
564             s->irq_target[irq] = value & ALL_CPU_MASK;
565         }
566     } else if (offset < 0xf00) {
567         /* Interrupt Configuration.  */
568         irq = (offset - 0xc00) * 4 + GIC_BASE_IRQ;
569         if (irq >= s->num_irq)
570             goto bad_reg;
571         if (irq < GIC_NR_SGIS)
572             value |= 0xaa;
573         for (i = 0; i < 4; i++) {
574             if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {
575                 if (value & (1 << (i * 2))) {
576                     GIC_SET_MODEL(irq + i);
577                 } else {
578                     GIC_CLEAR_MODEL(irq + i);
579                 }
580             }
581             if (value & (2 << (i * 2))) {
582                 GIC_SET_EDGE_TRIGGER(irq + i);
583             } else {
584                 GIC_CLEAR_EDGE_TRIGGER(irq + i);
585             }
586         }
587     } else if (offset < 0xf10) {
588         /* 0xf00 is only handled for 32-bit writes.  */
589         goto bad_reg;
590     } else if (offset < 0xf20) {
591         /* GICD_CPENDSGIRn */
592         if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {
593             goto bad_reg;
594         }
595         irq = (offset - 0xf10);
596 
597         s->sgi_pending[irq][cpu] &= ~value;
598         if (s->sgi_pending[irq][cpu] == 0) {
599             GIC_CLEAR_PENDING(irq, 1 << cpu);
600         }
601     } else if (offset < 0xf30) {
602         /* GICD_SPENDSGIRn */
603         if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {
604             goto bad_reg;
605         }
606         irq = (offset - 0xf20);
607 
608         GIC_SET_PENDING(irq, 1 << cpu);
609         s->sgi_pending[irq][cpu] |= value;
610     } else {
611         goto bad_reg;
612     }
613     gic_update(s);
614     return;
615 bad_reg:
616     qemu_log_mask(LOG_GUEST_ERROR,
617                   "gic_dist_writeb: Bad offset %x\n", (int)offset);
618 }
619 
620 static void gic_dist_writew(void *opaque, hwaddr offset,
621                             uint32_t value, MemTxAttrs attrs)
622 {
623     gic_dist_writeb(opaque, offset, value & 0xff, attrs);
624     gic_dist_writeb(opaque, offset + 1, value >> 8, attrs);
625 }
626 
627 static void gic_dist_writel(void *opaque, hwaddr offset,
628                             uint32_t value, MemTxAttrs attrs)
629 {
630     GICState *s = (GICState *)opaque;
631     if (offset == 0xf00) {
632         int cpu;
633         int irq;
634         int mask;
635         int target_cpu;
636 
637         cpu = gic_get_current_cpu(s);
638         irq = value & 0x3ff;
639         switch ((value >> 24) & 3) {
640         case 0:
641             mask = (value >> 16) & ALL_CPU_MASK;
642             break;
643         case 1:
644             mask = ALL_CPU_MASK ^ (1 << cpu);
645             break;
646         case 2:
647             mask = 1 << cpu;
648             break;
649         default:
650             DPRINTF("Bad Soft Int target filter\n");
651             mask = ALL_CPU_MASK;
652             break;
653         }
654         GIC_SET_PENDING(irq, mask);
655         target_cpu = ctz32(mask);
656         while (target_cpu < GIC_NCPU) {
657             s->sgi_pending[irq][target_cpu] |= (1 << cpu);
658             mask &= ~(1 << target_cpu);
659             target_cpu = ctz32(mask);
660         }
661         gic_update(s);
662         return;
663     }
664     gic_dist_writew(opaque, offset, value & 0xffff, attrs);
665     gic_dist_writew(opaque, offset + 2, value >> 16, attrs);
666 }
667 
668 static MemTxResult gic_dist_write(void *opaque, hwaddr offset, uint64_t data,
669                                   unsigned size, MemTxAttrs attrs)
670 {
671     switch (size) {
672     case 1:
673         gic_dist_writeb(opaque, offset, data, attrs);
674         return MEMTX_OK;
675     case 2:
676         gic_dist_writew(opaque, offset, data, attrs);
677         return MEMTX_OK;
678     case 4:
679         gic_dist_writel(opaque, offset, data, attrs);
680         return MEMTX_OK;
681     default:
682         return MEMTX_ERROR;
683     }
684 }
685 
686 static const MemoryRegionOps gic_dist_ops = {
687     .read_with_attrs = gic_dist_read,
688     .write_with_attrs = gic_dist_write,
689     .endianness = DEVICE_NATIVE_ENDIAN,
690 };
691 
692 static MemTxResult gic_cpu_read(GICState *s, int cpu, int offset,
693                                 uint64_t *data, MemTxAttrs attrs)
694 {
695     switch (offset) {
696     case 0x00: /* Control */
697         *data = s->cpu_enabled[cpu];
698         break;
699     case 0x04: /* Priority mask */
700         *data = s->priority_mask[cpu];
701         break;
702     case 0x08: /* Binary Point */
703         *data = s->bpr[cpu];
704         break;
705     case 0x0c: /* Acknowledge */
706         *data = gic_acknowledge_irq(s, cpu);
707         break;
708     case 0x14: /* Running Priority */
709         *data = s->running_priority[cpu];
710         break;
711     case 0x18: /* Highest Pending Interrupt */
712         *data = s->current_pending[cpu];
713         break;
714     case 0x1c: /* Aliased Binary Point */
715         *data = s->abpr[cpu];
716         break;
717     case 0xd0: case 0xd4: case 0xd8: case 0xdc:
718         *data = s->apr[(offset - 0xd0) / 4][cpu];
719         break;
720     default:
721         qemu_log_mask(LOG_GUEST_ERROR,
722                       "gic_cpu_read: Bad offset %x\n", (int)offset);
723         return MEMTX_ERROR;
724     }
725     return MEMTX_OK;
726 }
727 
728 static MemTxResult gic_cpu_write(GICState *s, int cpu, int offset,
729                                  uint32_t value, MemTxAttrs attrs)
730 {
731     switch (offset) {
732     case 0x00: /* Control */
733         s->cpu_enabled[cpu] = (value & 1);
734         DPRINTF("CPU %d %sabled\n", cpu, s->cpu_enabled[cpu] ? "En" : "Dis");
735         break;
736     case 0x04: /* Priority mask */
737         s->priority_mask[cpu] = (value & 0xff);
738         break;
739     case 0x08: /* Binary Point */
740         s->bpr[cpu] = (value & 0x7);
741         break;
742     case 0x10: /* End Of Interrupt */
743         gic_complete_irq(s, cpu, value & 0x3ff);
744         return MEMTX_OK;
745     case 0x1c: /* Aliased Binary Point */
746         if (s->revision >= 2) {
747             s->abpr[cpu] = (value & 0x7);
748         }
749         break;
750     case 0xd0: case 0xd4: case 0xd8: case 0xdc:
751         qemu_log_mask(LOG_UNIMP, "Writing APR not implemented\n");
752         break;
753     default:
754         qemu_log_mask(LOG_GUEST_ERROR,
755                       "gic_cpu_write: Bad offset %x\n", (int)offset);
756         return MEMTX_ERROR;
757     }
758     gic_update(s);
759     return MEMTX_OK;
760 }
761 
762 /* Wrappers to read/write the GIC CPU interface for the current CPU */
763 static MemTxResult gic_thiscpu_read(void *opaque, hwaddr addr, uint64_t *data,
764                                     unsigned size, MemTxAttrs attrs)
765 {
766     GICState *s = (GICState *)opaque;
767     return gic_cpu_read(s, gic_get_current_cpu(s), addr, data, attrs);
768 }
769 
770 static MemTxResult gic_thiscpu_write(void *opaque, hwaddr addr,
771                                      uint64_t value, unsigned size,
772                                      MemTxAttrs attrs)
773 {
774     GICState *s = (GICState *)opaque;
775     return gic_cpu_write(s, gic_get_current_cpu(s), addr, value, attrs);
776 }
777 
778 /* Wrappers to read/write the GIC CPU interface for a specific CPU.
779  * These just decode the opaque pointer into GICState* + cpu id.
780  */
781 static MemTxResult gic_do_cpu_read(void *opaque, hwaddr addr, uint64_t *data,
782                                    unsigned size, MemTxAttrs attrs)
783 {
784     GICState **backref = (GICState **)opaque;
785     GICState *s = *backref;
786     int id = (backref - s->backref);
787     return gic_cpu_read(s, id, addr, data, attrs);
788 }
789 
790 static MemTxResult gic_do_cpu_write(void *opaque, hwaddr addr,
791                                     uint64_t value, unsigned size,
792                                     MemTxAttrs attrs)
793 {
794     GICState **backref = (GICState **)opaque;
795     GICState *s = *backref;
796     int id = (backref - s->backref);
797     return gic_cpu_write(s, id, addr, value, attrs);
798 }
799 
800 static const MemoryRegionOps gic_thiscpu_ops = {
801     .read_with_attrs = gic_thiscpu_read,
802     .write_with_attrs = gic_thiscpu_write,
803     .endianness = DEVICE_NATIVE_ENDIAN,
804 };
805 
806 static const MemoryRegionOps gic_cpu_ops = {
807     .read_with_attrs = gic_do_cpu_read,
808     .write_with_attrs = gic_do_cpu_write,
809     .endianness = DEVICE_NATIVE_ENDIAN,
810 };
811 
812 void gic_init_irqs_and_distributor(GICState *s)
813 {
814     SysBusDevice *sbd = SYS_BUS_DEVICE(s);
815     int i;
816 
817     i = s->num_irq - GIC_INTERNAL;
818     /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
819      * GPIO array layout is thus:
820      *  [0..N-1] SPIs
821      *  [N..N+31] PPIs for CPU 0
822      *  [N+32..N+63] PPIs for CPU 1
823      *   ...
824      */
825     if (s->revision != REV_NVIC) {
826         i += (GIC_INTERNAL * s->num_cpu);
827     }
828     qdev_init_gpio_in(DEVICE(s), gic_set_irq, i);
829     for (i = 0; i < NUM_CPU(s); i++) {
830         sysbus_init_irq(sbd, &s->parent_irq[i]);
831     }
832     for (i = 0; i < NUM_CPU(s); i++) {
833         sysbus_init_irq(sbd, &s->parent_fiq[i]);
834     }
835     memory_region_init_io(&s->iomem, OBJECT(s), &gic_dist_ops, s,
836                           "gic_dist", 0x1000);
837 }
838 
839 static void arm_gic_realize(DeviceState *dev, Error **errp)
840 {
841     /* Device instance realize function for the GIC sysbus device */
842     int i;
843     GICState *s = ARM_GIC(dev);
844     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
845     ARMGICClass *agc = ARM_GIC_GET_CLASS(s);
846     Error *local_err = NULL;
847 
848     agc->parent_realize(dev, &local_err);
849     if (local_err) {
850         error_propagate(errp, local_err);
851         return;
852     }
853 
854     gic_init_irqs_and_distributor(s);
855 
856     /* Memory regions for the CPU interfaces (NVIC doesn't have these):
857      * a region for "CPU interface for this core", then a region for
858      * "CPU interface for core 0", "for core 1", ...
859      * NB that the memory region size of 0x100 applies for the 11MPCore
860      * and also cores following the GIC v1 spec (ie A9).
861      * GIC v2 defines a larger memory region (0x1000) so this will need
862      * to be extended when we implement A15.
863      */
864     memory_region_init_io(&s->cpuiomem[0], OBJECT(s), &gic_thiscpu_ops, s,
865                           "gic_cpu", 0x100);
866     for (i = 0; i < NUM_CPU(s); i++) {
867         s->backref[i] = s;
868         memory_region_init_io(&s->cpuiomem[i+1], OBJECT(s), &gic_cpu_ops,
869                               &s->backref[i], "gic_cpu", 0x100);
870     }
871     /* Distributor */
872     sysbus_init_mmio(sbd, &s->iomem);
873     /* cpu interfaces (one for "current cpu" plus one per cpu) */
874     for (i = 0; i <= NUM_CPU(s); i++) {
875         sysbus_init_mmio(sbd, &s->cpuiomem[i]);
876     }
877 }
878 
879 static void arm_gic_class_init(ObjectClass *klass, void *data)
880 {
881     DeviceClass *dc = DEVICE_CLASS(klass);
882     ARMGICClass *agc = ARM_GIC_CLASS(klass);
883 
884     agc->parent_realize = dc->realize;
885     dc->realize = arm_gic_realize;
886 }
887 
888 static const TypeInfo arm_gic_info = {
889     .name = TYPE_ARM_GIC,
890     .parent = TYPE_ARM_GIC_COMMON,
891     .instance_size = sizeof(GICState),
892     .class_init = arm_gic_class_init,
893     .class_size = sizeof(ARMGICClass),
894 };
895 
896 static void arm_gic_register_types(void)
897 {
898     type_register_static(&arm_gic_info);
899 }
900 
901 type_init(arm_gic_register_types)
902