xref: /qemu/hw/intc/mips_gic.c (revision 06b40d250ecfa1633209c2e431a7a38acfd03a98)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
7  * Authors: Sanjay Lal <sanjayl@kymasys.com>
8  *
9  * Copyright (C) 2016 Imagination Technologies
10  */
11 
12 #include "qemu/osdep.h"
13 #include "qemu/log.h"
14 #include "qemu/module.h"
15 #include "qapi/error.h"
16 #include "hw/sysbus.h"
17 #include "system/memory.h"
18 #include "system/kvm.h"
19 #include "system/reset.h"
20 #include "kvm_mips.h"
21 #include "hw/intc/mips_gic.h"
22 #include "hw/irq.h"
23 #include "hw/qdev-properties.h"
24 
mips_gic_set_vp_irq(MIPSGICState * gic,int vp,int pin)25 static void mips_gic_set_vp_irq(MIPSGICState *gic, int vp, int pin)
26 {
27     int ored_level = 0;
28     int i;
29 
30     /* ORing pending registers sharing same pin */
31     for (i = 0; i < gic->num_irq; i++) {
32         if ((gic->irq_state[i].map_pin & GIC_MAP_MSK) == pin &&
33                 gic->irq_state[i].map_vp == vp &&
34                 gic->irq_state[i].enabled) {
35             ored_level |= gic->irq_state[i].pending;
36         }
37         if (ored_level) {
38             /* no need to iterate all interrupts */
39             break;
40         }
41     }
42     if (((gic->vps[vp].compare_map & GIC_MAP_MSK) == pin) &&
43             (gic->vps[vp].mask & GIC_VP_MASK_CMP_MSK)) {
44         /* ORing with local pending register (count/compare) */
45         ored_level |= (gic->vps[vp].pend & GIC_VP_MASK_CMP_MSK) >>
46                       GIC_VP_MASK_CMP_SHF;
47     }
48     if (kvm_enabled())  {
49         kvm_mips_set_ipi_interrupt(env_archcpu(gic->vps[vp].env),
50                                    pin + GIC_CPU_PIN_OFFSET,
51                                    ored_level);
52     } else {
53         qemu_set_irq(gic->vps[vp].env->irq[pin + GIC_CPU_PIN_OFFSET],
54                      ored_level);
55     }
56 }
57 
gic_update_pin_for_irq(MIPSGICState * gic,int n_IRQ)58 static void gic_update_pin_for_irq(MIPSGICState *gic, int n_IRQ)
59 {
60     int vp = gic->irq_state[n_IRQ].map_vp;
61     int pin = gic->irq_state[n_IRQ].map_pin & GIC_MAP_MSK;
62 
63     if (vp < 0 || vp >= gic->num_vps) {
64         return;
65     }
66     mips_gic_set_vp_irq(gic, vp, pin);
67 }
68 
gic_set_irq(void * opaque,int n_IRQ,int level)69 static void gic_set_irq(void *opaque, int n_IRQ, int level)
70 {
71     MIPSGICState *gic = (MIPSGICState *) opaque;
72 
73     gic->irq_state[n_IRQ].pending = (uint8_t) level;
74     if (!gic->irq_state[n_IRQ].enabled) {
75         /* GIC interrupt source disabled */
76         return;
77     }
78     gic_update_pin_for_irq(gic, n_IRQ);
79 }
80 
81 #define OFFSET_CHECK(c)                         \
82     do {                                        \
83         if (!(c)) {                             \
84             goto bad_offset;                    \
85         }                                       \
86     } while (0)
87 
88 /* GIC Read VP Local/Other Registers */
gic_read_vp(MIPSGICState * gic,uint32_t vp_index,hwaddr addr,unsigned size)89 static uint64_t gic_read_vp(MIPSGICState *gic, uint32_t vp_index, hwaddr addr,
90                             unsigned size)
91 {
92     switch (addr) {
93     case GIC_VP_CTL_OFS:
94         return gic->vps[vp_index].ctl;
95     case GIC_VP_PEND_OFS:
96         mips_gictimer_get_sh_count(gic->gic_timer);
97         return gic->vps[vp_index].pend;
98     case GIC_VP_MASK_OFS:
99         return gic->vps[vp_index].mask;
100     case GIC_VP_COMPARE_MAP_OFS:
101         return gic->vps[vp_index].compare_map;
102     case GIC_VP_OTHER_ADDR_OFS:
103         return gic->vps[vp_index].other_addr;
104     case GIC_VP_IDENT_OFS:
105         return vp_index;
106     case GIC_VP_COMPARE_LO_OFS:
107         return mips_gictimer_get_vp_compare(gic->gic_timer, vp_index);
108     case GIC_VP_COMPARE_HI_OFS:
109         return 0;
110     default:
111         qemu_log_mask(LOG_UNIMP, "Read %d bytes at GIC offset LOCAL/OTHER 0x%"
112                       PRIx64 "\n", size, addr);
113         break;
114     }
115     return 0;
116 }
117 
gic_read(void * opaque,hwaddr addr,unsigned size)118 static uint64_t gic_read(void *opaque, hwaddr addr, unsigned size)
119 {
120     MIPSGICState *gic = (MIPSGICState *) opaque;
121     uint32_t vp_index = current_cpu->cpu_index;
122     uint64_t ret = 0;
123     int i, base, irq_src;
124     uint32_t other_index;
125 
126     switch (addr) {
127     case GIC_SH_CONFIG_OFS:
128         ret = gic->sh_config | (mips_gictimer_get_countstop(gic->gic_timer) <<
129                                GIC_SH_CONFIG_COUNTSTOP_SHF);
130         break;
131     case GIC_SH_COUNTERLO_OFS:
132         ret = mips_gictimer_get_sh_count(gic->gic_timer);
133         break;
134     case GIC_SH_COUNTERHI_OFS:
135         ret = 0;
136         break;
137     case GIC_SH_PEND_OFS ... GIC_SH_PEND_LAST_OFS:
138         /* each bit represents pending status for an interrupt pin */
139         base = (addr - GIC_SH_PEND_OFS) * 8;
140         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
141         for (i = 0; i < size * 8; i++) {
142             ret |= (uint64_t) (gic->irq_state[base + i].pending) << i;
143         }
144         break;
145     case GIC_SH_MASK_OFS ... GIC_SH_MASK_LAST_OFS:
146         /* each bit represents status for an interrupt pin */
147         base = (addr - GIC_SH_MASK_OFS) * 8;
148         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
149         for (i = 0; i < size * 8; i++) {
150             ret |= (uint64_t) (gic->irq_state[base + i].enabled) << i;
151         }
152         break;
153     case GIC_SH_MAP0_PIN_OFS ... GIC_SH_MAP255_PIN_OFS:
154         /* 32 bits per a pin */
155         irq_src = (addr - GIC_SH_MAP0_PIN_OFS) / 4;
156         OFFSET_CHECK(irq_src < gic->num_irq);
157         ret = gic->irq_state[irq_src].map_pin;
158         break;
159     case GIC_SH_MAP0_VP_OFS ... GIC_SH_MAP255_VP_LAST_OFS:
160         /* up to 32 bytes per a pin */
161         irq_src = (addr - GIC_SH_MAP0_VP_OFS) / 32;
162         OFFSET_CHECK(irq_src < gic->num_irq);
163         if ((gic->irq_state[irq_src].map_vp) >= 0) {
164             ret = (uint64_t) 1 << (gic->irq_state[irq_src].map_vp);
165         } else {
166             ret = 0;
167         }
168         break;
169     /* VP-Local Register */
170     case VP_LOCAL_SECTION_OFS ... (VP_LOCAL_SECTION_OFS + GIC_VL_BRK_GROUP):
171         ret = gic_read_vp(gic, vp_index, addr - VP_LOCAL_SECTION_OFS, size);
172         break;
173     /* VP-Other Register */
174     case VP_OTHER_SECTION_OFS ... (VP_OTHER_SECTION_OFS + GIC_VL_BRK_GROUP):
175         other_index = gic->vps[vp_index].other_addr;
176         ret = gic_read_vp(gic, other_index, addr - VP_OTHER_SECTION_OFS, size);
177         break;
178     /* User-Mode Visible section */
179     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERLO:
180         ret = mips_gictimer_get_sh_count(gic->gic_timer);
181         break;
182     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERHI:
183         ret = 0;
184         break;
185     default:
186         qemu_log_mask(LOG_UNIMP, "Read %d bytes at GIC offset 0x%" PRIx64 "\n",
187                       size, addr);
188         break;
189     }
190     return ret;
191 bad_offset:
192     qemu_log_mask(LOG_GUEST_ERROR, "Wrong GIC offset at 0x%" PRIx64 "\n", addr);
193     return 0;
194 }
195 
gic_timer_expire_cb(void * opaque,uint32_t vp_index)196 static void gic_timer_expire_cb(void *opaque, uint32_t vp_index)
197 {
198     MIPSGICState *gic = opaque;
199 
200     gic->vps[vp_index].pend |= (1 << GIC_LOCAL_INT_COMPARE);
201     if (gic->vps[vp_index].pend &
202             (gic->vps[vp_index].mask & GIC_VP_MASK_CMP_MSK)) {
203         if (gic->vps[vp_index].compare_map & GIC_MAP_TO_PIN_MSK) {
204             /* it is safe to set the irq high regardless of other GIC IRQs */
205             uint32_t pin = (gic->vps[vp_index].compare_map & GIC_MAP_MSK);
206             qemu_irq_raise(gic->vps[vp_index].env->irq
207                            [pin + GIC_CPU_PIN_OFFSET]);
208         }
209     }
210 }
211 
gic_timer_store_vp_compare(MIPSGICState * gic,uint32_t vp_index,uint64_t compare)212 static void gic_timer_store_vp_compare(MIPSGICState *gic, uint32_t vp_index,
213                                        uint64_t compare)
214 {
215     gic->vps[vp_index].pend &= ~(1 << GIC_LOCAL_INT_COMPARE);
216     if (gic->vps[vp_index].compare_map & GIC_MAP_TO_PIN_MSK) {
217         uint32_t pin = (gic->vps[vp_index].compare_map & GIC_MAP_MSK);
218         mips_gic_set_vp_irq(gic, vp_index, pin);
219     }
220     mips_gictimer_store_vp_compare(gic->gic_timer, vp_index, compare);
221 }
222 
223 /* GIC Write VP Local/Other Registers */
gic_write_vp(MIPSGICState * gic,uint32_t vp_index,hwaddr addr,uint64_t data,unsigned size)224 static void gic_write_vp(MIPSGICState *gic, uint32_t vp_index, hwaddr addr,
225                               uint64_t data, unsigned size)
226 {
227     switch (addr) {
228     case GIC_VP_CTL_OFS:
229         /* EIC isn't supported */
230         break;
231     case GIC_VP_RMASK_OFS:
232         gic->vps[vp_index].mask &= ~(data & GIC_VP_SET_RESET_MSK) &
233                                    GIC_VP_SET_RESET_MSK;
234         break;
235     case GIC_VP_SMASK_OFS:
236         gic->vps[vp_index].mask |= data & GIC_VP_SET_RESET_MSK;
237         break;
238     case GIC_VP_COMPARE_MAP_OFS:
239         /* EIC isn't supported */
240         OFFSET_CHECK((data & GIC_MAP_MSK) <= GIC_CPU_INT_MAX);
241         gic->vps[vp_index].compare_map = data & GIC_MAP_TO_PIN_REG_MSK;
242         break;
243     case GIC_VP_OTHER_ADDR_OFS:
244         OFFSET_CHECK(data < gic->num_vps);
245         gic->vps[vp_index].other_addr = data;
246         break;
247     case GIC_VP_COMPARE_LO_OFS:
248         gic_timer_store_vp_compare(gic, vp_index, data);
249         break;
250     default:
251         qemu_log_mask(LOG_UNIMP, "Write %d bytes at GIC offset LOCAL/OTHER "
252                       "0x%" PRIx64" 0x%08" PRIx64 "\n", size, addr, data);
253         break;
254     }
255     return;
256 bad_offset:
257     qemu_log_mask(LOG_GUEST_ERROR, "Wrong GIC offset at 0x%" PRIx64 "\n", addr);
258 }
259 
gic_write(void * opaque,hwaddr addr,uint64_t data,unsigned size)260 static void gic_write(void *opaque, hwaddr addr, uint64_t data, unsigned size)
261 {
262     int intr;
263     MIPSGICState *gic = (MIPSGICState *) opaque;
264     uint32_t vp_index = current_cpu->cpu_index;
265     int i, base, irq_src;
266     uint32_t other_index;
267 
268     switch (addr) {
269     case GIC_SH_CONFIG_OFS:
270         {
271             uint32_t pre_cntstop = mips_gictimer_get_countstop(gic->gic_timer);
272             uint32_t new_cntstop = (data & GIC_SH_CONFIG_COUNTSTOP_MSK) >>
273                                    GIC_SH_CONFIG_COUNTSTOP_SHF;
274             if (pre_cntstop != new_cntstop) {
275                 if (new_cntstop == 1) {
276                     mips_gictimer_stop_count(gic->gic_timer);
277                 } else {
278                     mips_gictimer_start_count(gic->gic_timer);
279                 }
280             }
281         }
282         break;
283     case GIC_SH_COUNTERLO_OFS:
284         if (mips_gictimer_get_countstop(gic->gic_timer)) {
285             mips_gictimer_store_sh_count(gic->gic_timer, data);
286         }
287         break;
288     case GIC_SH_RMASK_OFS ... GIC_SH_RMASK_LAST_OFS:
289         /* up to 64 bits per a pin */
290         base = (addr - GIC_SH_RMASK_OFS) * 8;
291         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
292         for (i = 0; i < size * 8; i++) {
293             gic->irq_state[base + i].enabled &= !((data >> i) & 1);
294             gic_update_pin_for_irq(gic, base + i);
295         }
296         break;
297     case GIC_SH_WEDGE_OFS:
298         /* Figure out which VP/HW Interrupt this maps to */
299         intr = data & ~GIC_SH_WEDGE_RW_MSK;
300         /* Mask/Enabled Checks */
301         OFFSET_CHECK(intr < gic->num_irq);
302         if (data & GIC_SH_WEDGE_RW_MSK) {
303             gic_set_irq(gic, intr, 1);
304         } else {
305             gic_set_irq(gic, intr, 0);
306         }
307         break;
308     case GIC_SH_SMASK_OFS ... GIC_SH_SMASK_LAST_OFS:
309         /* up to 64 bits per a pin */
310         base = (addr - GIC_SH_SMASK_OFS) * 8;
311         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
312         for (i = 0; i < size * 8; i++) {
313             gic->irq_state[base + i].enabled |= (data >> i) & 1;
314             gic_update_pin_for_irq(gic, base + i);
315         }
316         break;
317     case GIC_SH_MAP0_PIN_OFS ... GIC_SH_MAP255_PIN_OFS:
318         /* 32 bits per a pin */
319         irq_src = (addr - GIC_SH_MAP0_PIN_OFS) / 4;
320         OFFSET_CHECK(irq_src < gic->num_irq);
321         /* EIC isn't supported */
322         OFFSET_CHECK((data & GIC_MAP_MSK) <= GIC_CPU_INT_MAX);
323         gic->irq_state[irq_src].map_pin = data & GIC_MAP_TO_PIN_REG_MSK;
324         break;
325     case GIC_SH_MAP0_VP_OFS ... GIC_SH_MAP255_VP_LAST_OFS:
326         /* up to 32 bytes per a pin */
327         irq_src = (addr - GIC_SH_MAP0_VP_OFS) / 32;
328         OFFSET_CHECK(irq_src < gic->num_irq);
329         data = data ? ctz64(data) : -1;
330         OFFSET_CHECK(data < gic->num_vps);
331         gic->irq_state[irq_src].map_vp = data;
332         break;
333     case VP_LOCAL_SECTION_OFS ... (VP_LOCAL_SECTION_OFS + GIC_VL_BRK_GROUP):
334         gic_write_vp(gic, vp_index, addr - VP_LOCAL_SECTION_OFS, data, size);
335         break;
336     case VP_OTHER_SECTION_OFS ... (VP_OTHER_SECTION_OFS + GIC_VL_BRK_GROUP):
337         other_index = gic->vps[vp_index].other_addr;
338         gic_write_vp(gic, other_index, addr - VP_OTHER_SECTION_OFS, data, size);
339         break;
340     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERLO:
341     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERHI:
342         /* do nothing. Read-only section */
343         break;
344     default:
345         qemu_log_mask(LOG_UNIMP, "Write %d bytes at GIC offset 0x%" PRIx64
346                       " 0x%08" PRIx64 "\n", size, addr, data);
347         break;
348     }
349     return;
350 bad_offset:
351     qemu_log_mask(LOG_GUEST_ERROR, "Wrong GIC offset at 0x%" PRIx64 "\n", addr);
352 }
353 
gic_reset(void * opaque)354 static void gic_reset(void *opaque)
355 {
356     int i;
357     MIPSGICState *gic = (MIPSGICState *) opaque;
358     int numintrs = (gic->num_irq / 8) - 1;
359 
360     gic->sh_config = /* COUNTSTOP = 0 it is accessible via MIPSGICTimer*/
361                      /* CounterHi not implemented */
362                      (0            << GIC_SH_CONFIG_COUNTBITS_SHF) |
363                      (numintrs     << GIC_SH_CONFIG_NUMINTRS_SHF)  |
364                      (gic->num_vps << GIC_SH_CONFIG_PVPS_SHF);
365     for (i = 0; i < gic->num_vps; i++) {
366         gic->vps[i].ctl         = 0x0;
367         gic->vps[i].pend        = 0x0;
368         /* PERFCNT, TIMER and WD not implemented */
369         gic->vps[i].mask        = 0x32;
370         gic->vps[i].compare_map = GIC_MAP_TO_PIN_MSK;
371         mips_gictimer_store_vp_compare(gic->gic_timer, i, 0xffffffff);
372         gic->vps[i].other_addr  = 0x0;
373     }
374     for (i = 0; i < gic->num_irq; i++) {
375         gic->irq_state[i].enabled = 0;
376         gic->irq_state[i].pending = 0;
377         gic->irq_state[i].map_pin = GIC_MAP_TO_PIN_MSK;
378         gic->irq_state[i].map_vp  = -1;
379     }
380     mips_gictimer_store_sh_count(gic->gic_timer, 0);
381     /* COUNTSTOP = 0 */
382     mips_gictimer_start_count(gic->gic_timer);
383 }
384 
385 static const MemoryRegionOps gic_ops = {
386     .read = gic_read,
387     .write = gic_write,
388     .endianness = DEVICE_NATIVE_ENDIAN,
389     .impl = {
390         .max_access_size = 8,
391     },
392 };
393 
mips_gic_init(Object * obj)394 static void mips_gic_init(Object *obj)
395 {
396     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
397     MIPSGICState *s = MIPS_GIC(obj);
398 
399     memory_region_init_io(&s->mr, OBJECT(s), &gic_ops, s,
400                           "mips-gic", GIC_ADDRSPACE_SZ);
401     sysbus_init_mmio(sbd, &s->mr);
402     qemu_register_reset(gic_reset, s);
403 }
404 
mips_gic_realize(DeviceState * dev,Error ** errp)405 static void mips_gic_realize(DeviceState *dev, Error **errp)
406 {
407     MIPSGICState *s = MIPS_GIC(dev);
408     CPUState *cs = first_cpu;
409     int i;
410 
411     if (s->num_vps > GIC_MAX_VPS) {
412         error_setg(errp, "Exceeded maximum CPUs %d", s->num_vps);
413         return;
414     }
415     if ((s->num_irq > GIC_MAX_INTRS) || (s->num_irq % 8) || (s->num_irq <= 0)) {
416         error_setg(errp, "GIC supports up to %d external interrupts in "
417                    "multiples of 8 : %d", GIC_MAX_INTRS, s->num_irq);
418         return;
419     }
420     s->vps = g_new(MIPSGICVPState, s->num_vps);
421     s->irq_state = g_new(MIPSGICIRQState, s->num_irq);
422     /* Register the env for all VPs with the GIC */
423     for (i = 0; i < s->num_vps; i++) {
424         if (cs != NULL) {
425             s->vps[i].env = cpu_env(cs);
426             cs = CPU_NEXT(cs);
427         } else {
428             error_setg(errp,
429                "Unable to initialize GIC, CPUState for CPU#%d not valid.", i);
430             return;
431         }
432     }
433     s->gic_timer = mips_gictimer_init(s, s->num_vps, gic_timer_expire_cb);
434     qdev_init_gpio_in(dev, gic_set_irq, s->num_irq);
435     for (i = 0; i < s->num_irq; i++) {
436         s->irq_state[i].irq = qdev_get_gpio_in(dev, i);
437     }
438 }
439 
440 static const Property mips_gic_properties[] = {
441     DEFINE_PROP_UINT32("num-vp", MIPSGICState, num_vps, 1),
442     DEFINE_PROP_UINT32("num-irq", MIPSGICState, num_irq, 256),
443 };
444 
mips_gic_class_init(ObjectClass * klass,const void * data)445 static void mips_gic_class_init(ObjectClass *klass, const void *data)
446 {
447     DeviceClass *dc = DEVICE_CLASS(klass);
448 
449     device_class_set_props(dc, mips_gic_properties);
450     dc->realize = mips_gic_realize;
451 }
452 
453 static const TypeInfo mips_gic_info = {
454     .name          = TYPE_MIPS_GIC,
455     .parent        = TYPE_SYS_BUS_DEVICE,
456     .instance_size = sizeof(MIPSGICState),
457     .instance_init = mips_gic_init,
458     .class_init    = mips_gic_class_init,
459 };
460 
mips_gic_register_types(void)461 static void mips_gic_register_types(void)
462 {
463     type_register_static(&mips_gic_info);
464 }
465 
466 type_init(mips_gic_register_types)
467