xref: /openbmc/qemu/hw/intc/mips_gic.c (revision 6f5fd837)
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/hw.h"
17 #include "hw/sysbus.h"
18 #include "exec/memory.h"
19 #include "sysemu/sysemu.h"
20 #include "sysemu/kvm.h"
21 #include "kvm_mips.h"
22 #include "hw/intc/mips_gic.h"
23 
24 static void mips_gic_set_vp_irq(MIPSGICState *gic, int vp, int pin)
25 {
26     int ored_level = 0;
27     int i;
28 
29     /* ORing pending registers sharing same pin */
30     for (i = 0; i < gic->num_irq; i++) {
31         if ((gic->irq_state[i].map_pin & GIC_MAP_MSK) == pin &&
32                 gic->irq_state[i].map_vp == vp &&
33                 gic->irq_state[i].enabled) {
34             ored_level |= gic->irq_state[i].pending;
35         }
36         if (ored_level) {
37             /* no need to iterate all interrupts */
38             break;
39         }
40     }
41     if (((gic->vps[vp].compare_map & GIC_MAP_MSK) == pin) &&
42             (gic->vps[vp].mask & GIC_VP_MASK_CMP_MSK)) {
43         /* ORing with local pending register (count/compare) */
44         ored_level |= (gic->vps[vp].pend & GIC_VP_MASK_CMP_MSK) >>
45                       GIC_VP_MASK_CMP_SHF;
46     }
47     if (kvm_enabled())  {
48         kvm_mips_set_ipi_interrupt(env_archcpu(gic->vps[vp].env),
49                                    pin + GIC_CPU_PIN_OFFSET,
50                                    ored_level);
51     } else {
52         qemu_set_irq(gic->vps[vp].env->irq[pin + GIC_CPU_PIN_OFFSET],
53                      ored_level);
54     }
55 }
56 
57 static void gic_update_pin_for_irq(MIPSGICState *gic, int n_IRQ)
58 {
59     int vp = gic->irq_state[n_IRQ].map_vp;
60     int pin = gic->irq_state[n_IRQ].map_pin & GIC_MAP_MSK;
61 
62     if (vp < 0 || vp >= gic->num_vps) {
63         return;
64     }
65     mips_gic_set_vp_irq(gic, vp, pin);
66 }
67 
68 static void gic_set_irq(void *opaque, int n_IRQ, int level)
69 {
70     MIPSGICState *gic = (MIPSGICState *) opaque;
71 
72     gic->irq_state[n_IRQ].pending = (uint8_t) level;
73     if (!gic->irq_state[n_IRQ].enabled) {
74         /* GIC interrupt source disabled */
75         return;
76     }
77     gic_update_pin_for_irq(gic, n_IRQ);
78 }
79 
80 #define OFFSET_CHECK(c)                         \
81     do {                                        \
82         if (!(c)) {                             \
83             goto bad_offset;                    \
84         }                                       \
85     } while (0)
86 
87 /* GIC Read VP Local/Other Registers */
88 static uint64_t gic_read_vp(MIPSGICState *gic, uint32_t vp_index, hwaddr addr,
89                             unsigned size)
90 {
91     switch (addr) {
92     case GIC_VP_CTL_OFS:
93         return gic->vps[vp_index].ctl;
94     case GIC_VP_PEND_OFS:
95         mips_gictimer_get_sh_count(gic->gic_timer);
96         return gic->vps[vp_index].pend;
97     case GIC_VP_MASK_OFS:
98         return gic->vps[vp_index].mask;
99     case GIC_VP_COMPARE_MAP_OFS:
100         return gic->vps[vp_index].compare_map;
101     case GIC_VP_OTHER_ADDR_OFS:
102         return gic->vps[vp_index].other_addr;
103     case GIC_VP_IDENT_OFS:
104         return vp_index;
105     case GIC_VP_COMPARE_LO_OFS:
106         return mips_gictimer_get_vp_compare(gic->gic_timer, vp_index);
107     case GIC_VP_COMPARE_HI_OFS:
108         return 0;
109     default:
110         qemu_log_mask(LOG_UNIMP, "Read %d bytes at GIC offset LOCAL/OTHER 0x%"
111                       PRIx64 "\n", size, addr);
112         break;
113     }
114     return 0;
115 }
116 
117 static uint64_t gic_read(void *opaque, hwaddr addr, unsigned size)
118 {
119     MIPSGICState *gic = (MIPSGICState *) opaque;
120     uint32_t vp_index = current_cpu->cpu_index;
121     uint64_t ret = 0;
122     int i, base, irq_src;
123     uint32_t other_index;
124 
125     switch (addr) {
126     case GIC_SH_CONFIG_OFS:
127         ret = gic->sh_config | (mips_gictimer_get_countstop(gic->gic_timer) <<
128                                GIC_SH_CONFIG_COUNTSTOP_SHF);
129         break;
130     case GIC_SH_COUNTERLO_OFS:
131         ret = mips_gictimer_get_sh_count(gic->gic_timer);
132         break;
133     case GIC_SH_COUNTERHI_OFS:
134         ret = 0;
135         break;
136     case GIC_SH_PEND_OFS ... GIC_SH_PEND_LAST_OFS:
137         /* each bit represents pending status for an interrupt pin */
138         base = (addr - GIC_SH_PEND_OFS) * 8;
139         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
140         for (i = 0; i < size * 8; i++) {
141             ret |= (uint64_t) (gic->irq_state[base + i].pending) << i;
142         }
143         break;
144     case GIC_SH_MASK_OFS ... GIC_SH_MASK_LAST_OFS:
145         /* each bit represents status for an interrupt pin */
146         base = (addr - GIC_SH_MASK_OFS) * 8;
147         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
148         for (i = 0; i < size * 8; i++) {
149             ret |= (uint64_t) (gic->irq_state[base + i].enabled) << i;
150         }
151         break;
152     case GIC_SH_MAP0_PIN_OFS ... GIC_SH_MAP255_PIN_OFS:
153         /* 32 bits per a pin */
154         irq_src = (addr - GIC_SH_MAP0_PIN_OFS) / 4;
155         OFFSET_CHECK(irq_src < gic->num_irq);
156         ret = gic->irq_state[irq_src].map_pin;
157         break;
158     case GIC_SH_MAP0_VP_OFS ... GIC_SH_MAP255_VP_LAST_OFS:
159         /* up to 32 bytes per a pin */
160         irq_src = (addr - GIC_SH_MAP0_VP_OFS) / 32;
161         OFFSET_CHECK(irq_src < gic->num_irq);
162         if ((gic->irq_state[irq_src].map_vp) >= 0) {
163             ret = (uint64_t) 1 << (gic->irq_state[irq_src].map_vp);
164         } else {
165             ret = 0;
166         }
167         break;
168     /* VP-Local Register */
169     case VP_LOCAL_SECTION_OFS ... (VP_LOCAL_SECTION_OFS + GIC_VL_BRK_GROUP):
170         ret = gic_read_vp(gic, vp_index, addr - VP_LOCAL_SECTION_OFS, size);
171         break;
172     /* VP-Other Register */
173     case VP_OTHER_SECTION_OFS ... (VP_OTHER_SECTION_OFS + GIC_VL_BRK_GROUP):
174         other_index = gic->vps[vp_index].other_addr;
175         ret = gic_read_vp(gic, other_index, addr - VP_OTHER_SECTION_OFS, size);
176         break;
177     /* User-Mode Visible section */
178     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERLO:
179         ret = mips_gictimer_get_sh_count(gic->gic_timer);
180         break;
181     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERHI:
182         ret = 0;
183         break;
184     default:
185         qemu_log_mask(LOG_UNIMP, "Read %d bytes at GIC offset 0x%" PRIx64 "\n",
186                       size, addr);
187         break;
188     }
189     return ret;
190 bad_offset:
191     qemu_log_mask(LOG_GUEST_ERROR, "Wrong GIC offset at 0x%" PRIx64 "\n", addr);
192     return 0;
193 }
194 
195 static void gic_timer_expire_cb(void *opaque, uint32_t vp_index)
196 {
197     MIPSGICState *gic = opaque;
198 
199     gic->vps[vp_index].pend |= (1 << GIC_LOCAL_INT_COMPARE);
200     if (gic->vps[vp_index].pend &
201             (gic->vps[vp_index].mask & GIC_VP_MASK_CMP_MSK)) {
202         if (gic->vps[vp_index].compare_map & GIC_MAP_TO_PIN_MSK) {
203             /* it is safe to set the irq high regardless of other GIC IRQs */
204             uint32_t pin = (gic->vps[vp_index].compare_map & GIC_MAP_MSK);
205             qemu_irq_raise(gic->vps[vp_index].env->irq
206                            [pin + GIC_CPU_PIN_OFFSET]);
207         }
208     }
209 }
210 
211 static void gic_timer_store_vp_compare(MIPSGICState *gic, uint32_t vp_index,
212                                        uint64_t compare)
213 {
214     gic->vps[vp_index].pend &= ~(1 << GIC_LOCAL_INT_COMPARE);
215     if (gic->vps[vp_index].compare_map & GIC_MAP_TO_PIN_MSK) {
216         uint32_t pin = (gic->vps[vp_index].compare_map & GIC_MAP_MSK);
217         mips_gic_set_vp_irq(gic, vp_index, pin);
218     }
219     mips_gictimer_store_vp_compare(gic->gic_timer, vp_index, compare);
220 }
221 
222 /* GIC Write VP Local/Other Registers */
223 static void gic_write_vp(MIPSGICState *gic, uint32_t vp_index, hwaddr addr,
224                               uint64_t data, unsigned size)
225 {
226     switch (addr) {
227     case GIC_VP_CTL_OFS:
228         /* EIC isn't supported */
229         break;
230     case GIC_VP_RMASK_OFS:
231         gic->vps[vp_index].mask &= ~(data & GIC_VP_SET_RESET_MSK) &
232                                    GIC_VP_SET_RESET_MSK;
233         break;
234     case GIC_VP_SMASK_OFS:
235         gic->vps[vp_index].mask |= data & GIC_VP_SET_RESET_MSK;
236         break;
237     case GIC_VP_COMPARE_MAP_OFS:
238         /* EIC isn't supported */
239         OFFSET_CHECK((data & GIC_MAP_MSK) <= GIC_CPU_INT_MAX);
240         gic->vps[vp_index].compare_map = data & GIC_MAP_TO_PIN_REG_MSK;
241         break;
242     case GIC_VP_OTHER_ADDR_OFS:
243         OFFSET_CHECK(data < gic->num_vps);
244         gic->vps[vp_index].other_addr = data;
245         break;
246     case GIC_VP_COMPARE_LO_OFS:
247         gic_timer_store_vp_compare(gic, vp_index, data);
248         break;
249     default:
250         qemu_log_mask(LOG_UNIMP, "Write %d bytes at GIC offset LOCAL/OTHER "
251                       "0x%" PRIx64" 0x%08" PRIx64 "\n", size, addr, data);
252         break;
253     }
254     return;
255 bad_offset:
256     qemu_log_mask(LOG_GUEST_ERROR, "Wrong GIC offset at 0x%" PRIx64 "\n", addr);
257     return;
258 }
259 
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 
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 
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 
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 = cs->env_ptr;
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 Property mips_gic_properties[] = {
441     DEFINE_PROP_INT32("num-vp", MIPSGICState, num_vps, 1),
442     DEFINE_PROP_INT32("num-irq", MIPSGICState, num_irq, 256),
443     DEFINE_PROP_END_OF_LIST(),
444 };
445 
446 static void mips_gic_class_init(ObjectClass *klass, void *data)
447 {
448     DeviceClass *dc = DEVICE_CLASS(klass);
449 
450     dc->props = mips_gic_properties;
451     dc->realize = mips_gic_realize;
452 }
453 
454 static const TypeInfo mips_gic_info = {
455     .name          = TYPE_MIPS_GIC,
456     .parent        = TYPE_SYS_BUS_DEVICE,
457     .instance_size = sizeof(MIPSGICState),
458     .instance_init = mips_gic_init,
459     .class_init    = mips_gic_class_init,
460 };
461 
462 static void mips_gic_register_types(void)
463 {
464     type_register_static(&mips_gic_info);
465 }
466 
467 type_init(mips_gic_register_types)
468