xref: /openbmc/qemu/hw/intc/mips_gic.c (revision f6476697)
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 "exec/memory.h"
18 #include "sysemu/kvm.h"
19 #include "sysemu/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 
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 
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 
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 */
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 
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 
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 
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 */
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     return;
259 }
260 
261 static void gic_write(void *opaque, hwaddr addr, uint64_t data, unsigned size)
262 {
263     int intr;
264     MIPSGICState *gic = (MIPSGICState *) opaque;
265     uint32_t vp_index = current_cpu->cpu_index;
266     int i, base, irq_src;
267     uint32_t other_index;
268 
269     switch (addr) {
270     case GIC_SH_CONFIG_OFS:
271         {
272             uint32_t pre_cntstop = mips_gictimer_get_countstop(gic->gic_timer);
273             uint32_t new_cntstop = (data & GIC_SH_CONFIG_COUNTSTOP_MSK) >>
274                                    GIC_SH_CONFIG_COUNTSTOP_SHF;
275             if (pre_cntstop != new_cntstop) {
276                 if (new_cntstop == 1) {
277                     mips_gictimer_stop_count(gic->gic_timer);
278                 } else {
279                     mips_gictimer_start_count(gic->gic_timer);
280                 }
281             }
282         }
283         break;
284     case GIC_SH_COUNTERLO_OFS:
285         if (mips_gictimer_get_countstop(gic->gic_timer)) {
286             mips_gictimer_store_sh_count(gic->gic_timer, data);
287         }
288         break;
289     case GIC_SH_RMASK_OFS ... GIC_SH_RMASK_LAST_OFS:
290         /* up to 64 bits per a pin */
291         base = (addr - GIC_SH_RMASK_OFS) * 8;
292         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
293         for (i = 0; i < size * 8; i++) {
294             gic->irq_state[base + i].enabled &= !((data >> i) & 1);
295             gic_update_pin_for_irq(gic, base + i);
296         }
297         break;
298     case GIC_SH_WEDGE_OFS:
299         /* Figure out which VP/HW Interrupt this maps to */
300         intr = data & ~GIC_SH_WEDGE_RW_MSK;
301         /* Mask/Enabled Checks */
302         OFFSET_CHECK(intr < gic->num_irq);
303         if (data & GIC_SH_WEDGE_RW_MSK) {
304             gic_set_irq(gic, intr, 1);
305         } else {
306             gic_set_irq(gic, intr, 0);
307         }
308         break;
309     case GIC_SH_SMASK_OFS ... GIC_SH_SMASK_LAST_OFS:
310         /* up to 64 bits per a pin */
311         base = (addr - GIC_SH_SMASK_OFS) * 8;
312         OFFSET_CHECK((base + size * 8) <= gic->num_irq);
313         for (i = 0; i < size * 8; i++) {
314             gic->irq_state[base + i].enabled |= (data >> i) & 1;
315             gic_update_pin_for_irq(gic, base + i);
316         }
317         break;
318     case GIC_SH_MAP0_PIN_OFS ... GIC_SH_MAP255_PIN_OFS:
319         /* 32 bits per a pin */
320         irq_src = (addr - GIC_SH_MAP0_PIN_OFS) / 4;
321         OFFSET_CHECK(irq_src < gic->num_irq);
322         /* EIC isn't supported */
323         OFFSET_CHECK((data & GIC_MAP_MSK) <= GIC_CPU_INT_MAX);
324         gic->irq_state[irq_src].map_pin = data & GIC_MAP_TO_PIN_REG_MSK;
325         break;
326     case GIC_SH_MAP0_VP_OFS ... GIC_SH_MAP255_VP_LAST_OFS:
327         /* up to 32 bytes per a pin */
328         irq_src = (addr - GIC_SH_MAP0_VP_OFS) / 32;
329         OFFSET_CHECK(irq_src < gic->num_irq);
330         data = data ? ctz64(data) : -1;
331         OFFSET_CHECK(data < gic->num_vps);
332         gic->irq_state[irq_src].map_vp = data;
333         break;
334     case VP_LOCAL_SECTION_OFS ... (VP_LOCAL_SECTION_OFS + GIC_VL_BRK_GROUP):
335         gic_write_vp(gic, vp_index, addr - VP_LOCAL_SECTION_OFS, data, size);
336         break;
337     case VP_OTHER_SECTION_OFS ... (VP_OTHER_SECTION_OFS + GIC_VL_BRK_GROUP):
338         other_index = gic->vps[vp_index].other_addr;
339         gic_write_vp(gic, other_index, addr - VP_OTHER_SECTION_OFS, data, size);
340         break;
341     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERLO:
342     case USM_VISIBLE_SECTION_OFS + GIC_USER_MODE_COUNTERHI:
343         /* do nothing. Read-only section */
344         break;
345     default:
346         qemu_log_mask(LOG_UNIMP, "Write %d bytes at GIC offset 0x%" PRIx64
347                       " 0x%08" PRIx64 "\n", size, addr, data);
348         break;
349     }
350     return;
351 bad_offset:
352     qemu_log_mask(LOG_GUEST_ERROR, "Wrong GIC offset at 0x%" PRIx64 "\n", addr);
353 }
354 
355 static void gic_reset(void *opaque)
356 {
357     int i;
358     MIPSGICState *gic = (MIPSGICState *) opaque;
359     int numintrs = (gic->num_irq / 8) - 1;
360 
361     gic->sh_config = /* COUNTSTOP = 0 it is accessible via MIPSGICTimer*/
362                      /* CounterHi not implemented */
363                      (0            << GIC_SH_CONFIG_COUNTBITS_SHF) |
364                      (numintrs     << GIC_SH_CONFIG_NUMINTRS_SHF)  |
365                      (gic->num_vps << GIC_SH_CONFIG_PVPS_SHF);
366     for (i = 0; i < gic->num_vps; i++) {
367         gic->vps[i].ctl         = 0x0;
368         gic->vps[i].pend        = 0x0;
369         /* PERFCNT, TIMER and WD not implemented */
370         gic->vps[i].mask        = 0x32;
371         gic->vps[i].compare_map = GIC_MAP_TO_PIN_MSK;
372         mips_gictimer_store_vp_compare(gic->gic_timer, i, 0xffffffff);
373         gic->vps[i].other_addr  = 0x0;
374     }
375     for (i = 0; i < gic->num_irq; i++) {
376         gic->irq_state[i].enabled = 0;
377         gic->irq_state[i].pending = 0;
378         gic->irq_state[i].map_pin = GIC_MAP_TO_PIN_MSK;
379         gic->irq_state[i].map_vp  = -1;
380     }
381     mips_gictimer_store_sh_count(gic->gic_timer, 0);
382     /* COUNTSTOP = 0 */
383     mips_gictimer_start_count(gic->gic_timer);
384 }
385 
386 static const MemoryRegionOps gic_ops = {
387     .read = gic_read,
388     .write = gic_write,
389     .endianness = DEVICE_NATIVE_ENDIAN,
390     .impl = {
391         .max_access_size = 8,
392     },
393 };
394 
395 static void mips_gic_init(Object *obj)
396 {
397     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
398     MIPSGICState *s = MIPS_GIC(obj);
399 
400     memory_region_init_io(&s->mr, OBJECT(s), &gic_ops, s,
401                           "mips-gic", GIC_ADDRSPACE_SZ);
402     sysbus_init_mmio(sbd, &s->mr);
403     qemu_register_reset(gic_reset, s);
404 }
405 
406 static void mips_gic_realize(DeviceState *dev, Error **errp)
407 {
408     MIPSGICState *s = MIPS_GIC(dev);
409     CPUState *cs = first_cpu;
410     int i;
411 
412     if (s->num_vps > GIC_MAX_VPS) {
413         error_setg(errp, "Exceeded maximum CPUs %d", s->num_vps);
414         return;
415     }
416     if ((s->num_irq > GIC_MAX_INTRS) || (s->num_irq % 8) || (s->num_irq <= 0)) {
417         error_setg(errp, "GIC supports up to %d external interrupts in "
418                    "multiples of 8 : %d", GIC_MAX_INTRS, s->num_irq);
419         return;
420     }
421     s->vps = g_new(MIPSGICVPState, s->num_vps);
422     s->irq_state = g_new(MIPSGICIRQState, s->num_irq);
423     /* Register the env for all VPs with the GIC */
424     for (i = 0; i < s->num_vps; i++) {
425         if (cs != NULL) {
426             s->vps[i].env = cs->env_ptr;
427             cs = CPU_NEXT(cs);
428         } else {
429             error_setg(errp,
430                "Unable to initialize GIC, CPUState for CPU#%d not valid.", i);
431             return;
432         }
433     }
434     s->gic_timer = mips_gictimer_init(s, s->num_vps, gic_timer_expire_cb);
435     qdev_init_gpio_in(dev, gic_set_irq, s->num_irq);
436     for (i = 0; i < s->num_irq; i++) {
437         s->irq_state[i].irq = qdev_get_gpio_in(dev, i);
438     }
439 }
440 
441 static Property mips_gic_properties[] = {
442     DEFINE_PROP_INT32("num-vp", MIPSGICState, num_vps, 1),
443     DEFINE_PROP_INT32("num-irq", MIPSGICState, num_irq, 256),
444     DEFINE_PROP_END_OF_LIST(),
445 };
446 
447 static void mips_gic_class_init(ObjectClass *klass, void *data)
448 {
449     DeviceClass *dc = DEVICE_CLASS(klass);
450 
451     device_class_set_props(dc, mips_gic_properties);
452     dc->realize = mips_gic_realize;
453 }
454 
455 static const TypeInfo mips_gic_info = {
456     .name          = TYPE_MIPS_GIC,
457     .parent        = TYPE_SYS_BUS_DEVICE,
458     .instance_size = sizeof(MIPSGICState),
459     .instance_init = mips_gic_init,
460     .class_init    = mips_gic_class_init,
461 };
462 
463 static void mips_gic_register_types(void)
464 {
465     type_register_static(&mips_gic_info);
466 }
467 
468 type_init(mips_gic_register_types)
469