xref: /openbmc/qemu/hw/intc/arm_gicv3_dist.c (revision 34cc54fb)
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_bitmap_reg(GICv3State *s, MemTxAttrs attrs,
93                                   uint32_t *bmp, maskfn *maskfn,
94                                   int offset, uint32_t val)
95 {
96     /*
97      * Helper routine to implement writing to a "set" register
98      * (GICD_INMIR, 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      * offset should be the offset in bytes of the register from the start
103      * of its group.
104      */
105     int irq = offset * 8;
106 
107     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
108         return;
109     }
110     val &= mask_group_and_nsacr(s, attrs, maskfn, irq);
111     *gic_bmp_ptr32(bmp, irq) = val;
112     gicv3_update(s, irq, 32);
113 }
114 
115 static void gicd_write_set_bitmap_reg(GICv3State *s, MemTxAttrs attrs,
116                                       uint32_t *bmp,
117                                       maskfn *maskfn,
118                                       int offset, uint32_t val)
119 {
120     /* Helper routine to implement writing to a "set-bitmap" register
121      * (GICD_ISENABLER, GICD_ISPENDR, etc).
122      * Semantics implemented here:
123      * RAZ/WI for SGIs, PPIs, unimplemented IRQs
124      * Bits corresponding to Group 0 or Secure Group 1 interrupts RAZ/WI.
125      * Writing 1 means "set bit in bitmap"; writing 0 is ignored.
126      * offset should be the offset in bytes of the register from the start
127      * of its group.
128      */
129     int irq = offset * 8;
130 
131     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
132         return;
133     }
134     val &= mask_group_and_nsacr(s, attrs, maskfn, irq);
135     *gic_bmp_ptr32(bmp, irq) |= val;
136     gicv3_update(s, irq, 32);
137 }
138 
139 static void gicd_write_clear_bitmap_reg(GICv3State *s, MemTxAttrs attrs,
140                                         uint32_t *bmp,
141                                         maskfn *maskfn,
142                                         int offset, uint32_t val)
143 {
144     /* Helper routine to implement writing to a "clear-bitmap" register
145      * (GICD_ICENABLER, GICD_ICPENDR, etc).
146      * Semantics implemented here:
147      * RAZ/WI for SGIs, PPIs, unimplemented IRQs
148      * Bits corresponding to Group 0 or Secure Group 1 interrupts RAZ/WI.
149      * Writing 1 means "clear bit in bitmap"; writing 0 is ignored.
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 
155     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
156         return;
157     }
158     val &= mask_group_and_nsacr(s, attrs, maskfn, irq);
159     *gic_bmp_ptr32(bmp, irq) &= ~val;
160     gicv3_update(s, irq, 32);
161 }
162 
163 static uint32_t gicd_read_bitmap_reg(GICv3State *s, MemTxAttrs attrs,
164                                      uint32_t *bmp,
165                                      maskfn *maskfn,
166                                      int offset)
167 {
168     /* Helper routine to implement reading a "set/clear-bitmap" register
169      * (GICD_ICENABLER, GICD_ISENABLER, GICD_ICPENDR, etc).
170      * Semantics implemented here:
171      * RAZ/WI for SGIs, PPIs, unimplemented IRQs
172      * Bits corresponding to Group 0 or Secure Group 1 interrupts RAZ/WI.
173      * offset should be the offset in bytes of the register from the start
174      * of its group.
175      */
176     int irq = offset * 8;
177     uint32_t val;
178 
179     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
180         return 0;
181     }
182     val = *gic_bmp_ptr32(bmp, irq);
183     if (bmp == s->pending) {
184         /* The PENDING register is a special case -- for level triggered
185          * interrupts, the PENDING state is the logical OR of the state of
186          * the PENDING latch with the input line level.
187          */
188         uint32_t edge = *gic_bmp_ptr32(s->edge_trigger, irq);
189         uint32_t level = *gic_bmp_ptr32(s->level, irq);
190         val |= (~edge & level);
191     }
192     val &= mask_group_and_nsacr(s, attrs, maskfn, irq);
193     return val;
194 }
195 
196 static uint8_t gicd_read_ipriorityr(GICv3State *s, MemTxAttrs attrs, int irq)
197 {
198     /* Read the value of GICD_IPRIORITYR<n> for the specified interrupt,
199      * honouring security state (these are RAZ/WI for Group 0 or Secure
200      * Group 1 interrupts).
201      */
202     uint32_t prio;
203 
204     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
205         return 0;
206     }
207 
208     prio = s->gicd_ipriority[irq];
209 
210     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
211         if (!gicv3_gicd_group_test(s, irq)) {
212             /* Fields for Group 0 or Secure Group 1 interrupts are RAZ/WI */
213             return 0;
214         }
215         /* NS view of the interrupt priority */
216         prio = (prio << 1) & 0xff;
217     }
218     return prio;
219 }
220 
221 static void gicd_write_ipriorityr(GICv3State *s, MemTxAttrs attrs, int irq,
222                                   uint8_t value)
223 {
224     /* Write the value of GICD_IPRIORITYR<n> for the specified interrupt,
225      * honouring security state (these are RAZ/WI for Group 0 or Secure
226      * Group 1 interrupts).
227      */
228     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
229         return;
230     }
231 
232     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
233         if (!gicv3_gicd_group_test(s, irq)) {
234             /* Fields for Group 0 or Secure Group 1 interrupts are RAZ/WI */
235             return;
236         }
237         /* NS view of the interrupt priority */
238         value = 0x80 | (value >> 1);
239     }
240     s->gicd_ipriority[irq] = value;
241 }
242 
243 static uint64_t gicd_read_irouter(GICv3State *s, MemTxAttrs attrs, int irq)
244 {
245     /* Read the value of GICD_IROUTER<n> for the specified interrupt,
246      * honouring security state.
247      */
248     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
249         return 0;
250     }
251 
252     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
253         /* RAZ/WI for NS accesses to secure interrupts */
254         if (!gicv3_gicd_group_test(s, irq)) {
255             if (gicd_ns_access(s, irq) != 3) {
256                 return 0;
257             }
258         }
259     }
260 
261     return s->gicd_irouter[irq];
262 }
263 
264 static void gicd_write_irouter(GICv3State *s, MemTxAttrs attrs, int irq,
265                                uint64_t val)
266 {
267     /* Write the value of GICD_IROUTER<n> for the specified interrupt,
268      * honouring security state.
269      */
270     if (irq < GIC_INTERNAL || irq >= s->num_irq) {
271         return;
272     }
273 
274     if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
275         /* RAZ/WI for NS accesses to secure interrupts */
276         if (!gicv3_gicd_group_test(s, irq)) {
277             if (gicd_ns_access(s, irq) != 3) {
278                 return;
279             }
280         }
281     }
282 
283     s->gicd_irouter[irq] = val;
284     gicv3_cache_target_cpustate(s, irq);
285     gicv3_update(s, irq, 1);
286 }
287 
288 /**
289  * gicd_readb
290  * gicd_readw
291  * gicd_readl
292  * gicd_readq
293  * gicd_writeb
294  * gicd_writew
295  * gicd_writel
296  * gicd_writeq
297  *
298  * Return %true if the operation succeeded, %false otherwise.
299  */
300 
301 static bool gicd_readb(GICv3State *s, hwaddr offset,
302                        uint64_t *data, MemTxAttrs attrs)
303 {
304     /* Most GICv3 distributor registers do not support byte accesses. */
305     switch (offset) {
306     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
307     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
308     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
309         /* This GIC implementation always has affinity routing enabled,
310          * so these registers are all RAZ/WI.
311          */
312         return true;
313     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
314         *data = gicd_read_ipriorityr(s, attrs, offset - GICD_IPRIORITYR);
315         return true;
316     default:
317         return false;
318     }
319 }
320 
321 static bool gicd_writeb(GICv3State *s, hwaddr offset,
322                         uint64_t value, MemTxAttrs attrs)
323 {
324     /* Most GICv3 distributor registers do not support byte accesses. */
325     switch (offset) {
326     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
327     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
328     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
329         /* This GIC implementation always has affinity routing enabled,
330          * so these registers are all RAZ/WI.
331          */
332         return true;
333     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
334     {
335         int irq = offset - GICD_IPRIORITYR;
336 
337         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
338             return true;
339         }
340         gicd_write_ipriorityr(s, attrs, irq, value);
341         gicv3_update(s, irq, 1);
342         return true;
343     }
344     default:
345         return false;
346     }
347 }
348 
349 static bool gicd_readw(GICv3State *s, hwaddr offset,
350                        uint64_t *data, MemTxAttrs attrs)
351 {
352     /* Only GICD_SETSPI_NSR, GICD_CLRSPI_NSR, GICD_SETSPI_SR and GICD_SETSPI_NSR
353      * support 16 bit accesses, and those registers are all part of the
354      * optional message-based SPI feature which this GIC does not currently
355      * implement (ie for us GICD_TYPER.MBIS == 0), so for us they are
356      * reserved.
357      */
358     return false;
359 }
360 
361 static bool gicd_writew(GICv3State *s, hwaddr offset,
362                         uint64_t value, MemTxAttrs attrs)
363 {
364     /* Only GICD_SETSPI_NSR, GICD_CLRSPI_NSR, GICD_SETSPI_SR and GICD_SETSPI_NSR
365      * support 16 bit accesses, and those registers are all part of the
366      * optional message-based SPI feature which this GIC does not currently
367      * implement (ie for us GICD_TYPER.MBIS == 0), so for us they are
368      * reserved.
369      */
370     return false;
371 }
372 
373 static bool gicd_readl(GICv3State *s, hwaddr offset,
374                        uint64_t *data, MemTxAttrs attrs)
375 {
376     /* Almost all GICv3 distributor registers are 32-bit.
377      * Note that WO registers must return an UNKNOWN value on reads,
378      * not an abort.
379      */
380 
381     switch (offset) {
382     case GICD_CTLR:
383         if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
384             /* The NS view of the GICD_CTLR sees only certain bits:
385              * + bit [31] (RWP) is an alias of the Secure bit [31]
386              * + bit [4] (ARE_NS) is an alias of Secure bit [5]
387              * + bit [1] (EnableGrp1A) is an alias of Secure bit [1] if
388              *   NS affinity routing is enabled, otherwise RES0
389              * + bit [0] (EnableGrp1) is an alias of Secure bit [1] if
390              *   NS affinity routing is not enabled, otherwise RES0
391              * Since for QEMU affinity routing is always enabled
392              * for both S and NS this means that bits [4] and [5] are
393              * both always 1, and we can simply make the NS view
394              * be bits 31, 4 and 1 of the S view.
395              */
396             *data = s->gicd_ctlr & (GICD_CTLR_ARE_S |
397                                     GICD_CTLR_EN_GRP1NS |
398                                     GICD_CTLR_RWP);
399         } else {
400             *data = s->gicd_ctlr;
401         }
402         return true;
403     case GICD_TYPER:
404     {
405         /* For this implementation:
406          * No1N == 1 (1-of-N SPI interrupts not supported)
407          * A3V == 1 (non-zero values of Affinity level 3 supported)
408          * IDbits == 0xf (we support 16-bit interrupt identifiers)
409          * DVIS == 1 (Direct virtual LPI injection supported) if GICv4
410          * LPIS == 1 (LPIs are supported if affinity routing is enabled)
411          * num_LPIs == 0b00000 (bits [15:11],Number of LPIs as indicated
412          *                      by GICD_TYPER.IDbits)
413          * MBIS == 0 (message-based SPIs not supported)
414          * SecurityExtn == 1 if security extns supported
415          * NMI = 1 if Non-maskable interrupt property is supported
416          * CPUNumber == 0 since for us ARE is always 1
417          * ITLinesNumber == (((max SPI IntID + 1) / 32) - 1)
418          */
419         int itlinesnumber = (s->num_irq / 32) - 1;
420         /*
421          * SecurityExtn must be RAZ if GICD_CTLR.DS == 1, and
422          * "security extensions not supported" always implies DS == 1,
423          * so we only need to check the DS bit.
424          */
425         bool sec_extn = !(s->gicd_ctlr & GICD_CTLR_DS);
426         bool dvis = s->revision >= 4;
427 
428         *data = (1 << 25) | (1 << 24) | (dvis << 18) | (sec_extn << 10) |
429             (s->nmi_support << GICD_TYPER_NMI_SHIFT) |
430             (s->lpi_enable << GICD_TYPER_LPIS_SHIFT) |
431             (0xf << 19) | itlinesnumber;
432         return true;
433     }
434     case GICD_IIDR:
435         /* We claim to be an ARM r0p0 with a zero ProductID.
436          * This is the same as an r0p0 GIC-500.
437          */
438         *data = gicv3_iidr();
439         return true;
440     case GICD_STATUSR:
441         /* RAZ/WI for us (this is an optional register and our implementation
442          * does not track RO/WO/reserved violations to report them to the guest)
443          */
444         *data = 0;
445         return true;
446     case GICD_IGROUPR ... GICD_IGROUPR + 0x7f:
447     {
448         int irq;
449 
450         if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
451             *data = 0;
452             return true;
453         }
454         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
455         irq = (offset - GICD_IGROUPR) * 8;
456         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
457             *data = 0;
458             return true;
459         }
460         *data = *gic_bmp_ptr32(s->group, irq);
461         return true;
462     }
463     case GICD_ISENABLER ... GICD_ISENABLER + 0x7f:
464         *data = gicd_read_bitmap_reg(s, attrs, s->enabled, NULL,
465                                      offset - GICD_ISENABLER);
466         return true;
467     case GICD_ICENABLER ... GICD_ICENABLER + 0x7f:
468         *data = gicd_read_bitmap_reg(s, attrs, s->enabled, NULL,
469                                      offset - GICD_ICENABLER);
470         return true;
471     case GICD_ISPENDR ... GICD_ISPENDR + 0x7f:
472         *data = gicd_read_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge1,
473                                      offset - GICD_ISPENDR);
474         return true;
475     case GICD_ICPENDR ... GICD_ICPENDR + 0x7f:
476         *data = gicd_read_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge2,
477                                      offset - GICD_ICPENDR);
478         return true;
479     case GICD_ISACTIVER ... GICD_ISACTIVER + 0x7f:
480         *data = gicd_read_bitmap_reg(s, attrs, s->active, mask_nsacr_ge2,
481                                      offset - GICD_ISACTIVER);
482         return true;
483     case GICD_ICACTIVER ... GICD_ICACTIVER + 0x7f:
484         *data = gicd_read_bitmap_reg(s, attrs, s->active, mask_nsacr_ge2,
485                                      offset - GICD_ICACTIVER);
486         return true;
487     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
488     {
489         int i, irq = offset - GICD_IPRIORITYR;
490         uint32_t value = 0;
491 
492         for (i = irq + 3; i >= irq; i--) {
493             value <<= 8;
494             value |= gicd_read_ipriorityr(s, attrs, i);
495         }
496         *data = value;
497         return true;
498     }
499     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
500         /* RAZ/WI since affinity routing is always enabled */
501         *data = 0;
502         return true;
503     case GICD_ICFGR ... GICD_ICFGR + 0xff:
504     {
505         /* Here only the even bits are used; odd bits are RES0 */
506         int irq = (offset - GICD_ICFGR) * 4;
507         uint32_t value = 0;
508 
509         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
510             *data = 0;
511             return true;
512         }
513 
514         /* Since our edge_trigger bitmap is one bit per irq, we only need
515          * half of the 32-bit word, which we can then spread out
516          * into the odd bits.
517          */
518         value = *gic_bmp_ptr32(s->edge_trigger, irq & ~0x1f);
519         value &= mask_group_and_nsacr(s, attrs, NULL, irq & ~0x1f);
520         value = extract32(value, (irq & 0x1f) ? 16 : 0, 16);
521         value = half_shuffle32(value) << 1;
522         *data = value;
523         return true;
524     }
525     case GICD_IGRPMODR ... GICD_IGRPMODR + 0xff:
526     {
527         int irq;
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         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
537         irq = (offset - GICD_IGRPMODR) * 8;
538         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
539             *data = 0;
540             return true;
541         }
542         *data = *gic_bmp_ptr32(s->grpmod, irq);
543         return true;
544     }
545     case GICD_NSACR ... GICD_NSACR + 0xff:
546     {
547         /* Two bits per interrupt */
548         int irq = (offset - GICD_NSACR) * 4;
549 
550         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
551             *data = 0;
552             return true;
553         }
554 
555         if ((s->gicd_ctlr & GICD_CTLR_DS) || !attrs.secure) {
556             /* RAZ/WI if security disabled, or if
557              * security enabled and this is an NS access
558              */
559             *data = 0;
560             return true;
561         }
562 
563         *data = s->gicd_nsacr[irq / 16];
564         return true;
565     }
566     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
567     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
568         /* RAZ/WI since affinity routing is always enabled */
569         *data = 0;
570         return true;
571     case GICD_INMIR ... GICD_INMIR + 0x7f:
572         *data = (!s->nmi_support) ? 0 :
573                 gicd_read_bitmap_reg(s, attrs, s->nmi, NULL,
574                                      offset - GICD_INMIR);
575         return true;
576     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
577     {
578         uint64_t r;
579         int irq = (offset - GICD_IROUTER) / 8;
580 
581         r = gicd_read_irouter(s, attrs, irq);
582         if (offset & 7) {
583             *data = r >> 32;
584         } else {
585             *data = (uint32_t)r;
586         }
587         return true;
588     }
589     case GICD_IDREGS ... GICD_IDREGS + 0x2f:
590         /* ID registers */
591         *data = gicv3_idreg(s, offset - GICD_IDREGS, GICV3_PIDR0_DIST);
592         return true;
593     case GICD_SGIR:
594         /* WO registers, return unknown value */
595         qemu_log_mask(LOG_GUEST_ERROR,
596                       "%s: invalid guest read from WO register at offset "
597                       HWADDR_FMT_plx "\n", __func__, offset);
598         *data = 0;
599         return true;
600     default:
601         return false;
602     }
603 }
604 
605 static bool gicd_writel(GICv3State *s, hwaddr offset,
606                         uint64_t value, MemTxAttrs attrs)
607 {
608     /* Almost all GICv3 distributor registers are 32-bit. Note that
609      * RO registers must ignore writes, not abort.
610      */
611 
612     switch (offset) {
613     case GICD_CTLR:
614     {
615         uint32_t mask;
616         /* GICv3 5.3.20 */
617         if (s->gicd_ctlr & GICD_CTLR_DS) {
618             /* With only one security state, E1NWF is RAZ/WI, DS is RAO/WI,
619              * ARE is RAO/WI (affinity routing always on), and only
620              * bits 0 and 1 (group enables) are writable.
621              */
622             mask = GICD_CTLR_EN_GRP0 | GICD_CTLR_EN_GRP1NS;
623         } else {
624             if (attrs.secure) {
625                 /* for secure access:
626                  * ARE_NS and ARE_S are RAO/WI (affinity routing always on)
627                  * E1NWF is RAZ/WI (we don't support enable-1-of-n-wakeup)
628                  *
629                  * We can only modify bits[2:0] (the group enables).
630                  */
631                 mask = GICD_CTLR_DS | GICD_CTLR_EN_GRP0 | GICD_CTLR_EN_GRP1_ALL;
632             } else {
633                 /* For non secure access ARE_NS is RAO/WI and EnableGrp1
634                  * is RES0. The only writable bit is [1] (EnableGrp1A), which
635                  * is an alias of the Secure bit [1].
636                  */
637                 mask = GICD_CTLR_EN_GRP1NS;
638             }
639         }
640         s->gicd_ctlr = (s->gicd_ctlr & ~mask) | (value & mask);
641         if (value & mask & GICD_CTLR_DS) {
642             /* We just set DS, so the ARE_NS and EnG1S bits are now RES0.
643              * Note that this is a one-way transition because if DS is set
644              * then it's not writable, so it can only go back to 0 with a
645              * hardware reset.
646              */
647             s->gicd_ctlr &= ~(GICD_CTLR_EN_GRP1S | GICD_CTLR_ARE_NS);
648         }
649         gicv3_full_update(s);
650         return true;
651     }
652     case GICD_STATUSR:
653         /* RAZ/WI for our implementation */
654         return true;
655     case GICD_IGROUPR ... GICD_IGROUPR + 0x7f:
656     {
657         int irq;
658 
659         if (!attrs.secure && !(s->gicd_ctlr & GICD_CTLR_DS)) {
660             return true;
661         }
662         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
663         irq = (offset - GICD_IGROUPR) * 8;
664         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
665             return true;
666         }
667         *gic_bmp_ptr32(s->group, irq) = value;
668         gicv3_update(s, irq, 32);
669         return true;
670     }
671     case GICD_ISENABLER ... GICD_ISENABLER + 0x7f:
672         gicd_write_set_bitmap_reg(s, attrs, s->enabled, NULL,
673                                   offset - GICD_ISENABLER, value);
674         return true;
675     case GICD_ICENABLER ... GICD_ICENABLER + 0x7f:
676         gicd_write_clear_bitmap_reg(s, attrs, s->enabled, NULL,
677                                     offset - GICD_ICENABLER, value);
678         return true;
679     case GICD_ISPENDR ... GICD_ISPENDR + 0x7f:
680         gicd_write_set_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge1,
681                                   offset - GICD_ISPENDR, value);
682         return true;
683     case GICD_ICPENDR ... GICD_ICPENDR + 0x7f:
684         gicd_write_clear_bitmap_reg(s, attrs, s->pending, mask_nsacr_ge2,
685                                     offset - GICD_ICPENDR, value);
686         return true;
687     case GICD_ISACTIVER ... GICD_ISACTIVER + 0x7f:
688         gicd_write_set_bitmap_reg(s, attrs, s->active, NULL,
689                                   offset - GICD_ISACTIVER, value);
690         return true;
691     case GICD_ICACTIVER ... GICD_ICACTIVER + 0x7f:
692         gicd_write_clear_bitmap_reg(s, attrs, s->active, NULL,
693                                     offset - GICD_ICACTIVER, value);
694         return true;
695     case GICD_IPRIORITYR ... GICD_IPRIORITYR + 0x3ff:
696     {
697         int i, irq = offset - GICD_IPRIORITYR;
698 
699         if (irq < GIC_INTERNAL || irq + 3 >= s->num_irq) {
700             return true;
701         }
702 
703         for (i = irq; i < irq + 4; i++, value >>= 8) {
704             gicd_write_ipriorityr(s, attrs, i, value);
705         }
706         gicv3_update(s, irq, 4);
707         return true;
708     }
709     case GICD_ITARGETSR ... GICD_ITARGETSR + 0x3ff:
710         /* RAZ/WI since affinity routing is always enabled */
711         return true;
712     case GICD_ICFGR ... GICD_ICFGR + 0xff:
713     {
714         /* Here only the odd bits are used; even bits are RES0 */
715         int irq = (offset - GICD_ICFGR) * 4;
716         uint32_t mask, oldval;
717 
718         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
719             return true;
720         }
721 
722         /* Since our edge_trigger bitmap is one bit per irq, our input
723          * 32-bits will compress down into 16 bits which we need
724          * to write into the bitmap.
725          */
726         value = half_unshuffle32(value >> 1);
727         mask = mask_group_and_nsacr(s, attrs, NULL, irq & ~0x1f);
728         if (irq & 0x1f) {
729             value <<= 16;
730             mask &= 0xffff0000U;
731         } else {
732             mask &= 0xffff;
733         }
734         oldval = *gic_bmp_ptr32(s->edge_trigger, (irq & ~0x1f));
735         value = (oldval & ~mask) | (value & mask);
736         *gic_bmp_ptr32(s->edge_trigger, irq & ~0x1f) = value;
737         return true;
738     }
739     case GICD_IGRPMODR ... GICD_IGRPMODR + 0xff:
740     {
741         int irq;
742 
743         if ((s->gicd_ctlr & GICD_CTLR_DS) || !attrs.secure) {
744             /* RAZ/WI if security disabled, or if
745              * security enabled and this is an NS access
746              */
747             return true;
748         }
749         /* RAZ/WI for SGIs, PPIs, unimplemented irqs */
750         irq = (offset - GICD_IGRPMODR) * 8;
751         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
752             return true;
753         }
754         *gic_bmp_ptr32(s->grpmod, irq) = value;
755         gicv3_update(s, irq, 32);
756         return true;
757     }
758     case GICD_NSACR ... GICD_NSACR + 0xff:
759     {
760         /* Two bits per interrupt */
761         int irq = (offset - GICD_NSACR) * 4;
762 
763         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
764             return true;
765         }
766 
767         if ((s->gicd_ctlr & GICD_CTLR_DS) || !attrs.secure) {
768             /* RAZ/WI if security disabled, or if
769              * security enabled and this is an NS access
770              */
771             return true;
772         }
773 
774         s->gicd_nsacr[irq / 16] = value;
775         /* No update required as this only affects access permission checks */
776         return true;
777     }
778     case GICD_SGIR:
779         /* RES0 if affinity routing is enabled */
780         return true;
781     case GICD_CPENDSGIR ... GICD_CPENDSGIR + 0xf:
782     case GICD_SPENDSGIR ... GICD_SPENDSGIR + 0xf:
783         /* RAZ/WI since affinity routing is always enabled */
784         return true;
785     case GICD_INMIR ... GICD_INMIR + 0x7f:
786         if (s->nmi_support) {
787             gicd_write_bitmap_reg(s, attrs, s->nmi, NULL,
788                                   offset - GICD_INMIR, value);
789         }
790         return true;
791     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
792     {
793         uint64_t r;
794         int irq = (offset - GICD_IROUTER) / 8;
795 
796         if (irq < GIC_INTERNAL || irq >= s->num_irq) {
797             return true;
798         }
799 
800         /* Write half of the 64-bit register */
801         r = gicd_read_irouter(s, attrs, irq);
802         r = deposit64(r, (offset & 7) ? 32 : 0, 32, value);
803         gicd_write_irouter(s, attrs, irq, r);
804         return true;
805     }
806     case GICD_IDREGS ... GICD_IDREGS + 0x2f:
807     case GICD_TYPER:
808     case GICD_IIDR:
809         /* RO registers, ignore the write */
810         qemu_log_mask(LOG_GUEST_ERROR,
811                       "%s: invalid guest write to RO register at offset "
812                       HWADDR_FMT_plx "\n", __func__, offset);
813         return true;
814     default:
815         return false;
816     }
817 }
818 
819 static bool gicd_writeq(GICv3State *s, hwaddr offset,
820                         uint64_t value, MemTxAttrs attrs)
821 {
822     /* Our only 64-bit registers are GICD_IROUTER<n> */
823     int irq;
824 
825     switch (offset) {
826     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
827         irq = (offset - GICD_IROUTER) / 8;
828         gicd_write_irouter(s, attrs, irq, value);
829         return true;
830     default:
831         return false;
832     }
833 }
834 
835 static bool gicd_readq(GICv3State *s, hwaddr offset,
836                        uint64_t *data, MemTxAttrs attrs)
837 {
838     /* Our only 64-bit registers are GICD_IROUTER<n> */
839     int irq;
840 
841     switch (offset) {
842     case GICD_IROUTER ... GICD_IROUTER + 0x1fdf:
843         irq = (offset - GICD_IROUTER) / 8;
844         *data = gicd_read_irouter(s, attrs, irq);
845         return true;
846     default:
847         return false;
848     }
849 }
850 
851 MemTxResult gicv3_dist_read(void *opaque, hwaddr offset, uint64_t *data,
852                             unsigned size, MemTxAttrs attrs)
853 {
854     GICv3State *s = (GICv3State *)opaque;
855     bool r;
856 
857     switch (size) {
858     case 1:
859         r = gicd_readb(s, offset, data, attrs);
860         break;
861     case 2:
862         r = gicd_readw(s, offset, data, attrs);
863         break;
864     case 4:
865         r = gicd_readl(s, offset, data, attrs);
866         break;
867     case 8:
868         r = gicd_readq(s, offset, data, attrs);
869         break;
870     default:
871         r = false;
872         break;
873     }
874 
875     if (!r) {
876         qemu_log_mask(LOG_GUEST_ERROR,
877                       "%s: invalid guest read at offset " HWADDR_FMT_plx
878                       " size %u\n", __func__, offset, size);
879         trace_gicv3_dist_badread(offset, size, attrs.secure);
880         /* The spec requires that reserved registers are RAZ/WI;
881          * so use MEMTX_ERROR returns from leaf functions as a way to
882          * trigger the guest-error logging but don't return it to
883          * the caller, or we'll cause a spurious guest data abort.
884          */
885         *data = 0;
886     } else {
887         trace_gicv3_dist_read(offset, *data, size, attrs.secure);
888     }
889     return MEMTX_OK;
890 }
891 
892 MemTxResult gicv3_dist_write(void *opaque, hwaddr offset, uint64_t data,
893                              unsigned size, MemTxAttrs attrs)
894 {
895     GICv3State *s = (GICv3State *)opaque;
896     bool r;
897 
898     switch (size) {
899     case 1:
900         r = gicd_writeb(s, offset, data, attrs);
901         break;
902     case 2:
903         r = gicd_writew(s, offset, data, attrs);
904         break;
905     case 4:
906         r = gicd_writel(s, offset, data, attrs);
907         break;
908     case 8:
909         r = gicd_writeq(s, offset, data, attrs);
910         break;
911     default:
912         r = false;
913         break;
914     }
915 
916     if (!r) {
917         qemu_log_mask(LOG_GUEST_ERROR,
918                       "%s: invalid guest write at offset " HWADDR_FMT_plx
919                       " size %u\n", __func__, offset, size);
920         trace_gicv3_dist_badwrite(offset, data, size, attrs.secure);
921         /* The spec requires that reserved registers are RAZ/WI;
922          * so use MEMTX_ERROR returns from leaf functions as a way to
923          * trigger the guest-error logging but don't return it to
924          * the caller, or we'll cause a spurious guest data abort.
925          */
926     } else {
927         trace_gicv3_dist_write(offset, data, size, attrs.secure);
928     }
929     return MEMTX_OK;
930 }
931 
932 void gicv3_dist_set_irq(GICv3State *s, int irq, int level)
933 {
934     /* Update distributor state for a change in an external SPI input line */
935     if (level == gicv3_gicd_level_test(s, irq)) {
936         return;
937     }
938 
939     trace_gicv3_dist_set_irq(irq, level);
940 
941     gicv3_gicd_level_replace(s, irq, level);
942 
943     if (level) {
944         /* 0->1 edges latch the pending bit for edge-triggered interrupts */
945         if (gicv3_gicd_edge_trigger_test(s, irq)) {
946             gicv3_gicd_pending_set(s, irq);
947         }
948     }
949 
950     gicv3_update(s, irq, 1);
951 }
952