xref: /openbmc/qemu/hw/intc/arm_gicv3_dist.c (revision 2f44bea9)
1 /*
2  * ARM GICv3 emulation: Distributor
3  *
4  * Copyright (c) 2015 Huawei.
5  * Copyright (c) 2016 Linaro Limited.
6  * Written by Shlomo Pongratz, Peter Maydell
7  *
8  * This code is licensed under the GPL, version 2 or (at your option)
9  * any later version.
10  */
11 
12 #include "qemu/osdep.h"
13 #include "qemu/log.h"
14 #include "trace.h"
15 #include "gicv3_internal.h"
16 
17 /* The GICD_NSACR registers contain a two bit field for each interrupt which
18  * allows the guest to give NonSecure code access to registers controlling
19  * Secure interrupts:
20  *  0b00: no access (NS accesses to bits for Secure interrupts will RAZ/WI)
21  *  0b01: NS r/w accesses permitted to ISPENDR, SETSPI_NSR, SGIR
22  *  0b10: as 0b01, and also r/w to ICPENDR, r/o to ISACTIVER/ICACTIVER,
23  *        and w/o to CLRSPI_NSR
24  *  0b11: as 0b10, and also r/w to IROUTER and ITARGETSR
25  *
26  * Given a (multiple-of-32) interrupt number, these mask functions return
27  * a mask word where each bit is 1 if the NSACR settings permit access
28  * to the interrupt. The mask returned can then be ORed with the GICD_GROUP
29  * word for this set of interrupts to give an overall mask.
30  */
31 
32 typedef uint32_t maskfn(GICv3State *s, int irq);
33 
34 static uint32_t mask_nsacr_ge1(GICv3State *s, int irq)
35 {
36     /* Return a mask where each bit is set if the NSACR field is >= 1 */
37     uint64_t raw_nsacr = s->gicd_nsacr[irq / 16 + 1];
38 
39     raw_nsacr = raw_nsacr << 32 | s->gicd_nsacr[irq / 16];
40     raw_nsacr = (raw_nsacr >> 1) | raw_nsacr;
41     return half_unshuffle64(raw_nsacr);
42 }
43 
44 static uint32_t mask_nsacr_ge2(GICv3State *s, int irq)
45 {
46     /* Return a mask where each bit is set if the NSACR field is >= 2 */
47     uint64_t raw_nsacr = s->gicd_nsacr[irq / 16 + 1];
48 
49     raw_nsacr = raw_nsacr << 32 | s->gicd_nsacr[irq / 16];
50     raw_nsacr = raw_nsacr >> 1;
51     return half_unshuffle64(raw_nsacr);
52 }
53 
54 /* We don't need a mask_nsacr_ge3() because IROUTER<n> isn't a bitmap register,
55  * but it would be implemented using:
56  *  raw_nsacr = (raw_nsacr >> 1) & raw_nsacr;
57  */
58 
59 static uint32_t mask_group_and_nsacr(GICv3State *s, MemTxAttrs attrs,
60                                      maskfn *maskfn, int irq)
61 {
62     /* Return a 32-bit mask which should be applied for this set of 32
63      * interrupts; each bit is 1 if access is permitted by the
64      * combination of attrs.secure, GICD_GROUPR and GICD_NSACR.
65      */
66     uint32_t mask;
67 
68     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
69         /* bits for Group 0 or Secure Group 1 interrupts are RAZ/WI
70          * unless the NSACR bits permit access.
71          */
72         mask = *gic_bmp_ptr32(s->group, irq);
73         if (maskfn) {
74             mask |= maskfn(s, irq);
75         }
76         return mask;
77     }
78     return 0xFFFFFFFFU;
79 }
80 
81 static int gicd_ns_access(GICv3State *s, int irq)
82 {
83     /* Return the 2 bit NS_access<x> field from GICD_NSACR<n> for the
84      * specified interrupt.
85      */
86     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
87         return 0;
88     }
89     return extract32(s->gicd_nsacr[irq / 16], (irq % 16) * 2, 2);
90 }
91 
92 static void gicd_write_set_bitmap_reg(GICv3State *s, MemTxAttrs attrs,
93                                       uint32_t *bmp,
94                                       maskfn *maskfn,
95                                       int offset, uint32_t val)
96 {
97     /* Helper routine to implement writing to a "set-bitmap" register
98      * (GICD_ISENABLER, GICD_ISPENDR, etc).
99      * Semantics implemented here:
100      * RAZ/WI for SGIs, PPIs, unimplemented IRQs
101      * Bits corresponding to Group 0 or Secure Group 1 interrupts RAZ/WI.
102      * Writing 1 means "set bit in bitmap"; writing 0 is ignored.
103      * offset should be the offset in bytes of the register from the start
104      * of its group.
105      */
106     int irq = offset * 8;
107 
108     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
109         return;
110     }
111     val &= mask_group_and_nsacr(s, attrs, maskfn, irq);
112     *gic_bmp_ptr32(bmp, irq) |= val;
113     gicv3_update(s, irq, 32);
114 }
115 
116 static void gicd_write_clear_bitmap_reg(GICv3State *s, MemTxAttrs attrs,
117                                         uint32_t *bmp,
118                                         maskfn *maskfn,
119                                         int offset, uint32_t val)
120 {
121     /* Helper routine to implement writing to a "clear-bitmap" register
122      * (GICD_ICENABLER, GICD_ICPENDR, etc).
123      * Semantics implemented here:
124      * RAZ/WI for SGIs, PPIs, unimplemented IRQs
125      * Bits corresponding to Group 0 or Secure Group 1 interrupts RAZ/WI.
126      * Writing 1 means "clear bit in bitmap"; writing 0 is ignored.
127      * offset should be the offset in bytes of the register from the start
128      * of its group.
129      */
130     int irq = offset * 8;
131 
132     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
133         return;
134     }
135     val &= mask_group_and_nsacr(s, attrs, maskfn, irq);
136     *gic_bmp_ptr32(bmp, irq) &= ~val;
137     gicv3_update(s, irq, 32);
138 }
139 
140 static uint32_t gicd_read_bitmap_reg(GICv3State *s, MemTxAttrs attrs,
141                                      uint32_t *bmp,
142                                      maskfn *maskfn,
143                                      int offset)
144 {
145     /* Helper routine to implement reading a "set/clear-bitmap" register
146      * (GICD_ICENABLER, GICD_ISENABLER, GICD_ICPENDR, etc).
147      * Semantics implemented here:
148      * RAZ/WI for SGIs, PPIs, unimplemented IRQs
149      * Bits corresponding to Group 0 or Secure Group 1 interrupts RAZ/WI.
150      * offset should be the offset in bytes of the register from the start
151      * of its group.
152      */
153     int irq = offset * 8;
154     uint32_t val;
155 
156     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
157         return 0;
158     }
159     val = *gic_bmp_ptr32(bmp, irq);
160     if (bmp == s->pending) {
161         /* The PENDING register is a special case -- for level triggered
162          * interrupts, the PENDING state is the logical OR of the state of
163          * the PENDING latch with the input line level.
164          */
165         uint32_t edge = *gic_bmp_ptr32(s->edge_trigger, irq);
166         uint32_t level = *gic_bmp_ptr32(s->level, irq);
167         val |= (~edge & level);
168     }
169     val &= mask_group_and_nsacr(s, attrs, maskfn, irq);
170     return val;
171 }
172 
173 static uint8_t gicd_read_ipriorityr(GICv3State *s, MemTxAttrs attrs, int irq)
174 {
175     /* Read the value of GICD_IPRIORITYR<n> for the specified interrupt,
176      * honouring security state (these are RAZ/WI for Group 0 or Secure
177      * Group 1 interrupts).
178      */
179     uint32_t prio;
180 
181     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
182         return 0;
183     }
184 
185     prio = s->gicd_ipriority[irq];
186 
187     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
188         if (!gicv3_gicd_group_test(s, irq)) {
189             /* Fields for Group 0 or Secure Group 1 interrupts are RAZ/WI */
190             return 0;
191         }
192         /* NS view of the interrupt priority */
193         prio = (prio << 1) & 0xff;
194     }
195     return prio;
196 }
197 
198 static void gicd_write_ipriorityr(GICv3State *s, MemTxAttrs attrs, int irq,
199                                   uint8_t value)
200 {
201     /* Write the value of GICD_IPRIORITYR<n> for the specified interrupt,
202      * honouring security state (these are RAZ/WI for Group 0 or Secure
203      * Group 1 interrupts).
204      */
205     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
206         return;
207     }
208 
209     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
210         if (!gicv3_gicd_group_test(s, irq)) {
211             /* Fields for Group 0 or Secure Group 1 interrupts are RAZ/WI */
212             return;
213         }
214         /* NS view of the interrupt priority */
215         value = 0x80 | (value >> 1);
216     }
217     s->gicd_ipriority[irq] = value;
218 }
219 
220 static uint64_t gicd_read_irouter(GICv3State *s, MemTxAttrs attrs, int irq)
221 {
222     /* Read the value of GICD_IROUTER<n> for the specified interrupt,
223      * honouring security state.
224      */
225     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
226         return 0;
227     }
228 
229     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
230         /* RAZ/WI for NS accesses to secure interrupts */
231         if (!gicv3_gicd_group_test(s, irq)) {
232             if (gicd_ns_access(s, irq) != 3) {
233                 return 0;
234             }
235         }
236     }
237 
238     return s->gicd_irouter[irq];
239 }
240 
241 static void gicd_write_irouter(GICv3State *s, MemTxAttrs attrs, int irq,
242                                uint64_t val)
243 {
244     /* Write the value of GICD_IROUTER<n> for the specified interrupt,
245      * honouring security state.
246      */
247     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
248         return;
249     }
250 
251     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
252         /* RAZ/WI for NS accesses to secure interrupts */
253         if (!gicv3_gicd_group_test(s, irq)) {
254             if (gicd_ns_access(s, irq) != 3) {
255                 return;
256             }
257         }
258     }
259 
260     s->gicd_irouter[irq] = val;
261     gicv3_cache_target_cpustate(s, irq);
262     gicv3_update(s, irq, 1);
263 }
264 
265 /**
266  * gicd_readb
267  * gicd_readw
268  * gicd_readl
269  * gicd_readq
270  * gicd_writeb
271  * gicd_writew
272  * gicd_writel
273  * gicd_writeq
274  *
275  * Return %true if the operation succeeded, %false otherwise.
276  */
277 
278 static bool gicd_readb(GICv3State *s, hwaddr offset,
279                        uint64_t *data, MemTxAttrs attrs)
280 {
281     /* Most GICv3 distributor registers do not support byte accesses. */
282     switch (offset) {
283     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
284     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
285     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
286         /* This GIC implementation always has affinity routing enabled,
287          * so these registers are all RAZ/WI.
288          */
289         return true;
290     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
291         *data = gicd_read_ipriorityr(s, attrs, offset - GICD_IPRIORITYR);
292         return true;
293     default:
294         return false;
295     }
296 }
297 
298 static bool gicd_writeb(GICv3State *s, hwaddr offset,
299                         uint64_t value, MemTxAttrs attrs)
300 {
301     /* Most GICv3 distributor registers do not support byte accesses. */
302     switch (offset) {
303     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
304     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
305     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
306         /* This GIC implementation always has affinity routing enabled,
307          * so these registers are all RAZ/WI.
308          */
309         return true;
310     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
311     {
312         int irq = offset - GICD_IPRIORITYR;
313 
314         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
315             return true;
316         }
317         gicd_write_ipriorityr(s, attrs, irq, value);
318         gicv3_update(s, irq, 1);
319         return true;
320     }
321     default:
322         return false;
323     }
324 }
325 
326 static bool gicd_readw(GICv3State *s, hwaddr offset,
327                        uint64_t *data, MemTxAttrs attrs)
328 {
329     /* Only GICD_SETSPI_NSR, GICD_CLRSPI_NSR, GICD_SETSPI_SR and GICD_SETSPI_NSR
330      * support 16 bit accesses, and those registers are all part of the
331      * optional message-based SPI feature which this GIC does not currently
332      * implement (ie for us GICD_TYPER.MBIS == 0), so for us they are
333      * reserved.
334      */
335     return false;
336 }
337 
338 static bool gicd_writew(GICv3State *s, hwaddr offset,
339                         uint64_t value, MemTxAttrs attrs)
340 {
341     /* Only GICD_SETSPI_NSR, GICD_CLRSPI_NSR, GICD_SETSPI_SR and GICD_SETSPI_NSR
342      * support 16 bit accesses, and those registers are all part of the
343      * optional message-based SPI feature which this GIC does not currently
344      * implement (ie for us GICD_TYPER.MBIS == 0), so for us they are
345      * reserved.
346      */
347     return false;
348 }
349 
350 static bool gicd_readl(GICv3State *s, hwaddr offset,
351                        uint64_t *data, MemTxAttrs attrs)
352 {
353     /* Almost all GICv3 distributor registers are 32-bit.
354      * Note that WO registers must return an UNKNOWN value on reads,
355      * not an abort.
356      */
357 
358     switch (offset) {
359     case GICD_CTLR:
360         if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
361             /* The NS view of the GICD_CTLR sees only certain bits:
362              * + bit [31] (RWP) is an alias of the Secure bit [31]
363              * + bit [4] (ARE_NS) is an alias of Secure bit [5]
364              * + bit [1] (EnableGrp1A) is an alias of Secure bit [1] if
365              *   NS affinity routing is enabled, otherwise RES0
366              * + bit [0] (EnableGrp1) is an alias of Secure bit [1] if
367              *   NS affinity routing is not enabled, otherwise RES0
368              * Since for QEMU affinity routing is always enabled
369              * for both S and NS this means that bits [4] and [5] are
370              * both always 1, and we can simply make the NS view
371              * be bits 31, 4 and 1 of the S view.
372              */
373             *data = s->gicd_ctlr & (GICD_CTLR_ARE_S |
374                                     GICD_CTLR_EN_GRP1NS |
375                                     GICD_CTLR_RWP);
376         } else {
377             *data = s->gicd_ctlr;
378         }
379         return true;
380     case GICD_TYPER:
381     {
382         /* For this implementation:
383          * No1N == 1 (1-of-N SPI interrupts not supported)
384          * A3V == 1 (non-zero values of Affinity level 3 supported)
385          * IDbits == 0xf (we support 16-bit interrupt identifiers)
386          * DVIS == 0 (Direct virtual LPI injection not supported)
387          * LPIS == 1 (LPIs are supported if affinity routing is enabled)
388          * num_LPIs == 0b00000 (bits [15:11],Number of LPIs as indicated
389          *                      by GICD_TYPER.IDbits)
390          * MBIS == 0 (message-based SPIs not supported)
391          * SecurityExtn == 1 if security extns supported
392          * CPUNumber == 0 since for us ARE is always 1
393          * ITLinesNumber == (num external irqs / 32) - 1
394          */
395         int itlinesnumber = ((s->num_irq - GIC_INTERNAL) / 32) - 1;
396         /*
397          * SecurityExtn must be RAZ if GICD_CTLR.DS == 1, and
398          * "security extensions not supported" always implies DS == 1,
399          * so we only need to check the DS bit.
400          */
401         bool sec_extn = !(s->gicd_ctlr & GICD_CTLR_DS);
402 
403         *data = (1 << 25) | (1 << 24) | (sec_extn << 10) |
404             (s->lpi_enable << GICD_TYPER_LPIS_SHIFT) |
405             (0xf << 19) | itlinesnumber;
406         return true;
407     }
408     case GICD_IIDR:
409         /* We claim to be an ARM r0p0 with a zero ProductID.
410          * This is the same as an r0p0 GIC-500.
411          */
412         *data = gicv3_iidr();
413         return true;
414     case GICD_STATUSR:
415         /* RAZ/WI for us (this is an optional register and our implementation
416          * does not track RO/WO/reserved violations to report them to the guest)
417          */
418         *data = 0;
419         return true;
420     case GICD_IGROUPR ... GICD_IGROUPR + 0x7f:
421     {
422         int irq;
423 
424         if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
425             *data = 0;
426             return true;
427         }
428         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
429         irq = (offset - GICD_IGROUPR) * 8;
430         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
431             *data = 0;
432             return true;
433         }
434         *data = *gic_bmp_ptr32(s->group, irq);
435         return true;
436     }
437     case GICD_ISENABLER ... GICD_ISENABLER + 0x7f:
438         *data = gicd_read_bitmap_reg(s, attrs, s->enabled, NULL,
439                                      offset - GICD_ISENABLER);
440         return true;
441     case GICD_ICENABLER ... GICD_ICENABLER + 0x7f:
442         *data = gicd_read_bitmap_reg(s, attrs, s->enabled, NULL,
443                                      offset - GICD_ICENABLER);
444         return true;
445     case GICD_ISPENDR ... GICD_ISPENDR + 0x7f:
446         *data = gicd_read_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge1,
447                                      offset - GICD_ISPENDR);
448         return true;
449     case GICD_ICPENDR ... GICD_ICPENDR + 0x7f:
450         *data = gicd_read_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge2,
451                                      offset - GICD_ICPENDR);
452         return true;
453     case GICD_ISACTIVER ... GICD_ISACTIVER + 0x7f:
454         *data = gicd_read_bitmap_reg(s, attrs, s->active, mask_nsacr_ge2,
455                                      offset - GICD_ISACTIVER);
456         return true;
457     case GICD_ICACTIVER ... GICD_ICACTIVER + 0x7f:
458         *data = gicd_read_bitmap_reg(s, attrs, s->active, mask_nsacr_ge2,
459                                      offset - GICD_ICACTIVER);
460         return true;
461     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
462     {
463         int i, irq = offset - GICD_IPRIORITYR;
464         uint32_t value = 0;
465 
466         for (i = irq + 3; i >= irq; i--) {
467             value <<= 8;
468             value |= gicd_read_ipriorityr(s, attrs, i);
469         }
470         *data = value;
471         return true;
472     }
473     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
474         /* RAZ/WI since affinity routing is always enabled */
475         *data = 0;
476         return true;
477     case GICD_ICFGR ... GICD_ICFGR + 0xff:
478     {
479         /* Here only the even bits are used; odd bits are RES0 */
480         int irq = (offset - GICD_ICFGR) * 4;
481         uint32_t value = 0;
482 
483         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
484             *data = 0;
485             return true;
486         }
487 
488         /* Since our edge_trigger bitmap is one bit per irq, we only need
489          * half of the 32-bit word, which we can then spread out
490          * into the odd bits.
491          */
492         value = *gic_bmp_ptr32(s->edge_trigger, irq & ~0x1f);
493         value &= mask_group_and_nsacr(s, attrs, NULL, irq & ~0x1f);
494         value = extract32(value, (irq & 0x1f) ? 16 : 0, 16);
495         value = half_shuffle32(value) << 1;
496         *data = value;
497         return true;
498     }
499     case GICD_IGRPMODR ... GICD_IGRPMODR + 0xff:
500     {
501         int irq;
502 
503         if ((s->gicd_ctlr & GICD_CTLR_DS) || !attrs.secure) {
504             /* RAZ/WI if security disabled, or if
505              * security enabled and this is an NS access
506              */
507             *data = 0;
508             return true;
509         }
510         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
511         irq = (offset - GICD_IGRPMODR) * 8;
512         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
513             *data = 0;
514             return true;
515         }
516         *data = *gic_bmp_ptr32(s->grpmod, irq);
517         return true;
518     }
519     case GICD_NSACR ... GICD_NSACR + 0xff:
520     {
521         /* Two bits per interrupt */
522         int irq = (offset - GICD_NSACR) * 4;
523 
524         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
525             *data = 0;
526             return true;
527         }
528 
529         if ((s->gicd_ctlr & GICD_CTLR_DS) || !attrs.secure) {
530             /* RAZ/WI if security disabled, or if
531              * security enabled and this is an NS access
532              */
533             *data = 0;
534             return true;
535         }
536 
537         *data = s->gicd_nsacr[irq / 16];
538         return true;
539     }
540     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
541     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
542         /* RAZ/WI since affinity routing is always enabled */
543         *data = 0;
544         return true;
545     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
546     {
547         uint64_t r;
548         int irq = (offset - GICD_IROUTER) / 8;
549 
550         r = gicd_read_irouter(s, attrs, irq);
551         if (offset & 7) {
552             *data = r >> 32;
553         } else {
554             *data = (uint32_t)r;
555         }
556         return true;
557     }
558     case GICD_IDREGS ... GICD_IDREGS + 0x2f:
559         /* ID registers */
560         *data = gicv3_idreg(offset - GICD_IDREGS);
561         return true;
562     case GICD_SGIR:
563         /* WO registers, return unknown value */
564         qemu_log_mask(LOG_GUEST_ERROR,
565                       "%s: invalid guest read from WO register at offset "
566                       TARGET_FMT_plx "\n", __func__, offset);
567         *data = 0;
568         return true;
569     default:
570         return false;
571     }
572 }
573 
574 static bool gicd_writel(GICv3State *s, hwaddr offset,
575                         uint64_t value, MemTxAttrs attrs)
576 {
577     /* Almost all GICv3 distributor registers are 32-bit. Note that
578      * RO registers must ignore writes, not abort.
579      */
580 
581     switch (offset) {
582     case GICD_CTLR:
583     {
584         uint32_t mask;
585         /* GICv3 5.3.20 */
586         if (s->gicd_ctlr & GICD_CTLR_DS) {
587             /* With only one security state, E1NWF is RAZ/WI, DS is RAO/WI,
588              * ARE is RAO/WI (affinity routing always on), and only
589              * bits 0 and 1 (group enables) are writable.
590              */
591             mask = GICD_CTLR_EN_GRP0 | GICD_CTLR_EN_GRP1NS;
592         } else {
593             if (attrs.secure) {
594                 /* for secure access:
595                  * ARE_NS and ARE_S are RAO/WI (affinity routing always on)
596                  * E1NWF is RAZ/WI (we don't support enable-1-of-n-wakeup)
597                  *
598                  * We can only modify bits[2:0] (the group enables).
599                  */
600                 mask = GICD_CTLR_DS | GICD_CTLR_EN_GRP0 | GICD_CTLR_EN_GRP1_ALL;
601             } else {
602                 /* For non secure access ARE_NS is RAO/WI and EnableGrp1
603                  * is RES0. The only writable bit is [1] (EnableGrp1A), which
604                  * is an alias of the Secure bit [1].
605                  */
606                 mask = GICD_CTLR_EN_GRP1NS;
607             }
608         }
609         s->gicd_ctlr = (s->gicd_ctlr & ~mask) | (value & mask);
610         if (value & mask & GICD_CTLR_DS) {
611             /* We just set DS, so the ARE_NS and EnG1S bits are now RES0.
612              * Note that this is a one-way transition because if DS is set
613              * then it's not writeable, so it can only go back to 0 with a
614              * hardware reset.
615              */
616             s->gicd_ctlr &= ~(GICD_CTLR_EN_GRP1S | GICD_CTLR_ARE_NS);
617         }
618         gicv3_full_update(s);
619         return true;
620     }
621     case GICD_STATUSR:
622         /* RAZ/WI for our implementation */
623         return true;
624     case GICD_IGROUPR ... GICD_IGROUPR + 0x7f:
625     {
626         int irq;
627 
628         if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
629             return true;
630         }
631         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
632         irq = (offset - GICD_IGROUPR) * 8;
633         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
634             return true;
635         }
636         *gic_bmp_ptr32(s->group, irq) = value;
637         gicv3_update(s, irq, 32);
638         return true;
639     }
640     case GICD_ISENABLER ... GICD_ISENABLER + 0x7f:
641         gicd_write_set_bitmap_reg(s, attrs, s->enabled, NULL,
642                                   offset - GICD_ISENABLER, value);
643         return true;
644     case GICD_ICENABLER ... GICD_ICENABLER + 0x7f:
645         gicd_write_clear_bitmap_reg(s, attrs, s->enabled, NULL,
646                                     offset - GICD_ICENABLER, value);
647         return true;
648     case GICD_ISPENDR ... GICD_ISPENDR + 0x7f:
649         gicd_write_set_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge1,
650                                   offset - GICD_ISPENDR, value);
651         return true;
652     case GICD_ICPENDR ... GICD_ICPENDR + 0x7f:
653         gicd_write_clear_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge2,
654                                     offset - GICD_ICPENDR, value);
655         return true;
656     case GICD_ISACTIVER ... GICD_ISACTIVER + 0x7f:
657         gicd_write_set_bitmap_reg(s, attrs, s->active, NULL,
658                                   offset - GICD_ISACTIVER, value);
659         return true;
660     case GICD_ICACTIVER ... GICD_ICACTIVER + 0x7f:
661         gicd_write_clear_bitmap_reg(s, attrs, s->active, NULL,
662                                     offset - GICD_ICACTIVER, value);
663         return true;
664     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
665     {
666         int i, irq = offset - GICD_IPRIORITYR;
667 
668         if (irq < GIC_INTERNAL || irq + 3 >= s->num_irq) {
669             return true;
670         }
671 
672         for (i = irq; i < irq + 4; i++, value >>= 8) {
673             gicd_write_ipriorityr(s, attrs, i, value);
674         }
675         gicv3_update(s, irq, 4);
676         return true;
677     }
678     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
679         /* RAZ/WI since affinity routing is always enabled */
680         return true;
681     case GICD_ICFGR ... GICD_ICFGR + 0xff:
682     {
683         /* Here only the odd bits are used; even bits are RES0 */
684         int irq = (offset - GICD_ICFGR) * 4;
685         uint32_t mask, oldval;
686 
687         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
688             return true;
689         }
690 
691         /* Since our edge_trigger bitmap is one bit per irq, our input
692          * 32-bits will compress down into 16 bits which we need
693          * to write into the bitmap.
694          */
695         value = half_unshuffle32(value >> 1);
696         mask = mask_group_and_nsacr(s, attrs, NULL, irq & ~0x1f);
697         if (irq & 0x1f) {
698             value <<= 16;
699             mask &= 0xffff0000U;
700         } else {
701             mask &= 0xffff;
702         }
703         oldval = *gic_bmp_ptr32(s->edge_trigger, (irq & ~0x1f));
704         value = (oldval & ~mask) | (value & mask);
705         *gic_bmp_ptr32(s->edge_trigger, irq & ~0x1f) = value;
706         return true;
707     }
708     case GICD_IGRPMODR ... GICD_IGRPMODR + 0xff:
709     {
710         int irq;
711 
712         if ((s->gicd_ctlr & GICD_CTLR_DS) || !attrs.secure) {
713             /* RAZ/WI if security disabled, or if
714              * security enabled and this is an NS access
715              */
716             return true;
717         }
718         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
719         irq = (offset - GICD_IGRPMODR) * 8;
720         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
721             return true;
722         }
723         *gic_bmp_ptr32(s->grpmod, irq) = value;
724         gicv3_update(s, irq, 32);
725         return true;
726     }
727     case GICD_NSACR ... GICD_NSACR + 0xff:
728     {
729         /* Two bits per interrupt */
730         int irq = (offset - GICD_NSACR) * 4;
731 
732         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
733             return true;
734         }
735 
736         if ((s->gicd_ctlr & GICD_CTLR_DS) || !attrs.secure) {
737             /* RAZ/WI if security disabled, or if
738              * security enabled and this is an NS access
739              */
740             return true;
741         }
742 
743         s->gicd_nsacr[irq / 16] = value;
744         /* No update required as this only affects access permission checks */
745         return true;
746     }
747     case GICD_SGIR:
748         /* RES0 if affinity routing is enabled */
749         return true;
750     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
751     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
752         /* RAZ/WI since affinity routing is always enabled */
753         return true;
754     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
755     {
756         uint64_t r;
757         int irq = (offset - GICD_IROUTER) / 8;
758 
759         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
760             return true;
761         }
762 
763         /* Write half of the 64-bit register */
764         r = gicd_read_irouter(s, attrs, irq);
765         r = deposit64(r, (offset & 7) ? 32 : 0, 32, value);
766         gicd_write_irouter(s, attrs, irq, r);
767         return true;
768     }
769     case GICD_IDREGS ... GICD_IDREGS + 0x2f:
770     case GICD_TYPER:
771     case GICD_IIDR:
772         /* RO registers, ignore the write */
773         qemu_log_mask(LOG_GUEST_ERROR,
774                       "%s: invalid guest write to RO register at offset "
775                       TARGET_FMT_plx "\n", __func__, offset);
776         return true;
777     default:
778         return false;
779     }
780 }
781 
782 static bool gicd_writeq(GICv3State *s, hwaddr offset,
783                         uint64_t value, MemTxAttrs attrs)
784 {
785     /* Our only 64-bit registers are GICD_IROUTER<n> */
786     int irq;
787 
788     switch (offset) {
789     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
790         irq = (offset - GICD_IROUTER) / 8;
791         gicd_write_irouter(s, attrs, irq, value);
792         return true;
793     default:
794         return false;
795     }
796 }
797 
798 static bool gicd_readq(GICv3State *s, hwaddr offset,
799                        uint64_t *data, MemTxAttrs attrs)
800 {
801     /* Our only 64-bit registers are GICD_IROUTER<n> */
802     int irq;
803 
804     switch (offset) {
805     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
806         irq = (offset - GICD_IROUTER) / 8;
807         *data = gicd_read_irouter(s, attrs, irq);
808         return true;
809     default:
810         return false;
811     }
812 }
813 
814 MemTxResult gicv3_dist_read(void *opaque, hwaddr offset, uint64_t *data,
815                             unsigned size, MemTxAttrs attrs)
816 {
817     GICv3State *s = (GICv3State *)opaque;
818     bool r;
819 
820     switch (size) {
821     case 1:
822         r = gicd_readb(s, offset, data, attrs);
823         break;
824     case 2:
825         r = gicd_readw(s, offset, data, attrs);
826         break;
827     case 4:
828         r = gicd_readl(s, offset, data, attrs);
829         break;
830     case 8:
831         r = gicd_readq(s, offset, data, attrs);
832         break;
833     default:
834         r = false;
835         break;
836     }
837 
838     if (!r) {
839         qemu_log_mask(LOG_GUEST_ERROR,
840                       "%s: invalid guest read at offset " TARGET_FMT_plx
841                       "size %u\n", __func__, offset, size);
842         trace_gicv3_dist_badread(offset, size, attrs.secure);
843         /* The spec requires that reserved registers are RAZ/WI;
844          * so use MEMTX_ERROR returns from leaf functions as a way to
845          * trigger the guest-error logging but don't return it to
846          * the caller, or we'll cause a spurious guest data abort.
847          */
848         *data = 0;
849     } else {
850         trace_gicv3_dist_read(offset, *data, size, attrs.secure);
851     }
852     return MEMTX_OK;
853 }
854 
855 MemTxResult gicv3_dist_write(void *opaque, hwaddr offset, uint64_t data,
856                              unsigned size, MemTxAttrs attrs)
857 {
858     GICv3State *s = (GICv3State *)opaque;
859     bool r;
860 
861     switch (size) {
862     case 1:
863         r = gicd_writeb(s, offset, data, attrs);
864         break;
865     case 2:
866         r = gicd_writew(s, offset, data, attrs);
867         break;
868     case 4:
869         r = gicd_writel(s, offset, data, attrs);
870         break;
871     case 8:
872         r = gicd_writeq(s, offset, data, attrs);
873         break;
874     default:
875         r = false;
876         break;
877     }
878 
879     if (!r) {
880         qemu_log_mask(LOG_GUEST_ERROR,
881                       "%s: invalid guest write at offset " TARGET_FMT_plx
882                       "size %u\n", __func__, offset, size);
883         trace_gicv3_dist_badwrite(offset, data, size, attrs.secure);
884         /* The spec requires that reserved registers are RAZ/WI;
885          * so use MEMTX_ERROR returns from leaf functions as a way to
886          * trigger the guest-error logging but don't return it to
887          * the caller, or we'll cause a spurious guest data abort.
888          */
889     } else {
890         trace_gicv3_dist_write(offset, data, size, attrs.secure);
891     }
892     return MEMTX_OK;
893 }
894 
895 void gicv3_dist_set_irq(GICv3State *s, int irq, int level)
896 {
897     /* Update distributor state for a change in an external SPI input line */
898     if (level == gicv3_gicd_level_test(s, irq)) {
899         return;
900     }
901 
902     trace_gicv3_dist_set_irq(irq, level);
903 
904     gicv3_gicd_level_replace(s, irq, level);
905 
906     if (level) {
907         /* 0->1 edges latch the pending bit for edge-triggered interrupts */
908         if (gicv3_gicd_edge_trigger_test(s, irq)) {
909             gicv3_gicd_pending_set(s, irq);
910         }
911     }
912 
913     gicv3_update(s, irq, 1);
914 }
915