2 * ARM Nested Vectored Interrupt Controller
4 * Copyright (c) 2006-2007 CodeSourcery.
5 * Written by Paul Brook
7 * This code is licensed under the GPL.
9 * The ARMv7M System controller is fairly tightly tied in with the
10 * NVIC. Much of that is also implemented here.
14 #include "qemu/timer.h"
16 #include "exec/address-spaces.h"
17 #include "arm_gic_internal.h"
27 MemoryRegion sysregmem
;
28 MemoryRegion gic_iomem_alias
;
29 MemoryRegion container
;
33 #define TYPE_NVIC "armv7m_nvic"
36 * @parent_reset: the parent class' reset handler.
38 * A model of the v7M NVIC and System Controller
40 typedef struct NVICClass
{
42 ARMGICClass parent_class
;
44 DeviceRealize parent_realize
;
45 void (*parent_reset
)(DeviceState
*dev
);
48 #define NVIC_CLASS(klass) \
49 OBJECT_CLASS_CHECK(NVICClass, (klass), TYPE_NVIC)
50 #define NVIC_GET_CLASS(obj) \
51 OBJECT_GET_CLASS(NVICClass, (obj), TYPE_NVIC)
53 OBJECT_CHECK(nvic_state, (obj), TYPE_NVIC)
55 static const uint8_t nvic_id
[] = {
56 0x00, 0xb0, 0x1b, 0x00, 0x0d, 0xe0, 0x05, 0xb1
59 /* qemu timers run at 1GHz. We want something closer to 1MHz. */
60 #define SYSTICK_SCALE 1000ULL
62 #define SYSTICK_ENABLE (1 << 0)
63 #define SYSTICK_TICKINT (1 << 1)
64 #define SYSTICK_CLKSOURCE (1 << 2)
65 #define SYSTICK_COUNTFLAG (1 << 16)
67 int system_clock_scale
;
69 /* Conversion factor from qemu timer to SysTick frequencies. */
70 static inline int64_t systick_scale(nvic_state
*s
)
72 if (s
->systick
.control
& SYSTICK_CLKSOURCE
)
73 return system_clock_scale
;
78 static void systick_reload(nvic_state
*s
, int reset
)
81 s
->systick
.tick
= qemu_get_clock_ns(vm_clock
);
82 s
->systick
.tick
+= (s
->systick
.reload
+ 1) * systick_scale(s
);
83 qemu_mod_timer(s
->systick
.timer
, s
->systick
.tick
);
86 static void systick_timer_tick(void * opaque
)
88 nvic_state
*s
= (nvic_state
*)opaque
;
89 s
->systick
.control
|= SYSTICK_COUNTFLAG
;
90 if (s
->systick
.control
& SYSTICK_TICKINT
) {
91 /* Trigger the interrupt. */
92 armv7m_nvic_set_pending(s
, ARMV7M_EXCP_SYSTICK
);
94 if (s
->systick
.reload
== 0) {
95 s
->systick
.control
&= ~SYSTICK_ENABLE
;
101 static void systick_reset(nvic_state
*s
)
103 s
->systick
.control
= 0;
104 s
->systick
.reload
= 0;
106 qemu_del_timer(s
->systick
.timer
);
109 /* The external routines use the hardware vector numbering, ie. the first
110 IRQ is #16. The internal GIC routines use #32 as the first IRQ. */
111 void armv7m_nvic_set_pending(void *opaque
, int irq
)
113 nvic_state
*s
= (nvic_state
*)opaque
;
116 gic_set_pending_private(&s
->gic
, 0, irq
);
119 /* Make pending IRQ active. */
120 int armv7m_nvic_acknowledge_irq(void *opaque
)
122 nvic_state
*s
= (nvic_state
*)opaque
;
125 irq
= gic_acknowledge_irq(&s
->gic
, 0);
127 hw_error("Interrupt but no vector\n");
133 void armv7m_nvic_complete_irq(void *opaque
, int irq
)
135 nvic_state
*s
= (nvic_state
*)opaque
;
138 gic_complete_irq(&s
->gic
, 0, irq
);
141 static uint32_t nvic_readl(nvic_state
*s
, uint32_t offset
)
147 case 4: /* Interrupt Control Type. */
148 return (s
->num_irq
/ 32) - 1;
149 case 0x10: /* SysTick Control and Status. */
150 val
= s
->systick
.control
;
151 s
->systick
.control
&= ~SYSTICK_COUNTFLAG
;
153 case 0x14: /* SysTick Reload Value. */
154 return s
->systick
.reload
;
155 case 0x18: /* SysTick Current Value. */
158 if ((s
->systick
.control
& SYSTICK_ENABLE
) == 0)
160 t
= qemu_get_clock_ns(vm_clock
);
161 if (t
>= s
->systick
.tick
)
163 val
= ((s
->systick
.tick
- (t
+ 1)) / systick_scale(s
)) + 1;
164 /* The interrupt in triggered when the timer reaches zero.
165 However the counter is not reloaded until the next clock
166 tick. This is a hack to return zero during the first tick. */
167 if (val
> s
->systick
.reload
)
171 case 0x1c: /* SysTick Calibration Value. */
173 case 0xd00: /* CPUID Base. */
174 return cpu_single_env
->cp15
.c0_cpuid
;
175 case 0xd04: /* Interrypt Control State. */
177 val
= s
->gic
.running_irq
[0];
180 } else if (val
>= 32) {
184 if (s
->gic
.running_irq
[0] == 1023
185 || s
->gic
.last_active
[s
->gic
.running_irq
[0]][0] == 1023) {
189 if (s
->gic
.current_pending
[0] != 1023)
190 val
|= (s
->gic
.current_pending
[0] << 12);
192 for (irq
= 32; irq
< s
->num_irq
; irq
++) {
193 if (s
->gic
.irq_state
[irq
].pending
) {
199 if (s
->gic
.irq_state
[ARMV7M_EXCP_SYSTICK
].pending
)
202 if (s
->gic
.irq_state
[ARMV7M_EXCP_PENDSV
].pending
)
205 if (s
->gic
.irq_state
[ARMV7M_EXCP_NMI
].pending
)
208 case 0xd08: /* Vector Table Offset. */
209 return cpu_single_env
->v7m
.vecbase
;
210 case 0xd0c: /* Application Interrupt/Reset Control. */
212 case 0xd10: /* System Control. */
213 /* TODO: Implement SLEEPONEXIT. */
215 case 0xd14: /* Configuration Control. */
216 /* TODO: Implement Configuration Control bits. */
218 case 0xd24: /* System Handler Status. */
220 if (s
->gic
.irq_state
[ARMV7M_EXCP_MEM
].active
) val
|= (1 << 0);
221 if (s
->gic
.irq_state
[ARMV7M_EXCP_BUS
].active
) val
|= (1 << 1);
222 if (s
->gic
.irq_state
[ARMV7M_EXCP_USAGE
].active
) val
|= (1 << 3);
223 if (s
->gic
.irq_state
[ARMV7M_EXCP_SVC
].active
) val
|= (1 << 7);
224 if (s
->gic
.irq_state
[ARMV7M_EXCP_DEBUG
].active
) val
|= (1 << 8);
225 if (s
->gic
.irq_state
[ARMV7M_EXCP_PENDSV
].active
) val
|= (1 << 10);
226 if (s
->gic
.irq_state
[ARMV7M_EXCP_SYSTICK
].active
) val
|= (1 << 11);
227 if (s
->gic
.irq_state
[ARMV7M_EXCP_USAGE
].pending
) val
|= (1 << 12);
228 if (s
->gic
.irq_state
[ARMV7M_EXCP_MEM
].pending
) val
|= (1 << 13);
229 if (s
->gic
.irq_state
[ARMV7M_EXCP_BUS
].pending
) val
|= (1 << 14);
230 if (s
->gic
.irq_state
[ARMV7M_EXCP_SVC
].pending
) val
|= (1 << 15);
231 if (s
->gic
.irq_state
[ARMV7M_EXCP_MEM
].enabled
) val
|= (1 << 16);
232 if (s
->gic
.irq_state
[ARMV7M_EXCP_BUS
].enabled
) val
|= (1 << 17);
233 if (s
->gic
.irq_state
[ARMV7M_EXCP_USAGE
].enabled
) val
|= (1 << 18);
235 case 0xd28: /* Configurable Fault Status. */
236 /* TODO: Implement Fault Status. */
237 qemu_log_mask(LOG_UNIMP
, "Configurable Fault Status unimplemented\n");
239 case 0xd2c: /* Hard Fault Status. */
240 case 0xd30: /* Debug Fault Status. */
241 case 0xd34: /* Mem Manage Address. */
242 case 0xd38: /* Bus Fault Address. */
243 case 0xd3c: /* Aux Fault Status. */
244 /* TODO: Implement fault status registers. */
245 qemu_log_mask(LOG_UNIMP
, "Fault status registers unimplemented\n");
247 case 0xd40: /* PFR0. */
249 case 0xd44: /* PRF1. */
251 case 0xd48: /* DFR0. */
253 case 0xd4c: /* AFR0. */
255 case 0xd50: /* MMFR0. */
257 case 0xd54: /* MMFR1. */
259 case 0xd58: /* MMFR2. */
261 case 0xd5c: /* MMFR3. */
263 case 0xd60: /* ISAR0. */
265 case 0xd64: /* ISAR1. */
267 case 0xd68: /* ISAR2. */
269 case 0xd6c: /* ISAR3. */
271 case 0xd70: /* ISAR4. */
273 /* TODO: Implement debug registers. */
275 qemu_log_mask(LOG_GUEST_ERROR
, "NVIC: Bad read offset 0x%x\n", offset
);
280 static void nvic_writel(nvic_state
*s
, uint32_t offset
, uint32_t value
)
284 case 0x10: /* SysTick Control and Status. */
285 oldval
= s
->systick
.control
;
286 s
->systick
.control
&= 0xfffffff8;
287 s
->systick
.control
|= value
& 7;
288 if ((oldval
^ value
) & SYSTICK_ENABLE
) {
289 int64_t now
= qemu_get_clock_ns(vm_clock
);
290 if (value
& SYSTICK_ENABLE
) {
291 if (s
->systick
.tick
) {
292 s
->systick
.tick
+= now
;
293 qemu_mod_timer(s
->systick
.timer
, s
->systick
.tick
);
295 systick_reload(s
, 1);
298 qemu_del_timer(s
->systick
.timer
);
299 s
->systick
.tick
-= now
;
300 if (s
->systick
.tick
< 0)
303 } else if ((oldval
^ value
) & SYSTICK_CLKSOURCE
) {
304 /* This is a hack. Force the timer to be reloaded
305 when the reference clock is changed. */
306 systick_reload(s
, 1);
309 case 0x14: /* SysTick Reload Value. */
310 s
->systick
.reload
= value
;
312 case 0x18: /* SysTick Current Value. Writes reload the timer. */
313 systick_reload(s
, 1);
314 s
->systick
.control
&= ~SYSTICK_COUNTFLAG
;
316 case 0xd04: /* Interrupt Control State. */
317 if (value
& (1 << 31)) {
318 armv7m_nvic_set_pending(s
, ARMV7M_EXCP_NMI
);
320 if (value
& (1 << 28)) {
321 armv7m_nvic_set_pending(s
, ARMV7M_EXCP_PENDSV
);
322 } else if (value
& (1 << 27)) {
323 s
->gic
.irq_state
[ARMV7M_EXCP_PENDSV
].pending
= 0;
326 if (value
& (1 << 26)) {
327 armv7m_nvic_set_pending(s
, ARMV7M_EXCP_SYSTICK
);
328 } else if (value
& (1 << 25)) {
329 s
->gic
.irq_state
[ARMV7M_EXCP_SYSTICK
].pending
= 0;
333 case 0xd08: /* Vector Table Offset. */
334 cpu_single_env
->v7m
.vecbase
= value
& 0xffffff80;
336 case 0xd0c: /* Application Interrupt/Reset Control. */
337 if ((value
>> 16) == 0x05fa) {
339 qemu_log_mask(LOG_UNIMP
, "VECTCLRACTIVE unimplemented\n");
342 qemu_log_mask(LOG_UNIMP
, "AIRCR system reset unimplemented\n");
346 case 0xd10: /* System Control. */
347 case 0xd14: /* Configuration Control. */
348 /* TODO: Implement control registers. */
349 qemu_log_mask(LOG_UNIMP
, "NVIC: SCR and CCR unimplemented\n");
351 case 0xd24: /* System Handler Control. */
352 /* TODO: Real hardware allows you to set/clear the active bits
353 under some circumstances. We don't implement this. */
354 s
->gic
.irq_state
[ARMV7M_EXCP_MEM
].enabled
= (value
& (1 << 16)) != 0;
355 s
->gic
.irq_state
[ARMV7M_EXCP_BUS
].enabled
= (value
& (1 << 17)) != 0;
356 s
->gic
.irq_state
[ARMV7M_EXCP_USAGE
].enabled
= (value
& (1 << 18)) != 0;
358 case 0xd28: /* Configurable Fault Status. */
359 case 0xd2c: /* Hard Fault Status. */
360 case 0xd30: /* Debug Fault Status. */
361 case 0xd34: /* Mem Manage Address. */
362 case 0xd38: /* Bus Fault Address. */
363 case 0xd3c: /* Aux Fault Status. */
364 qemu_log_mask(LOG_UNIMP
,
365 "NVIC: fault status registers unimplemented\n");
367 case 0xf00: /* Software Triggered Interrupt Register */
368 if ((value
& 0x1ff) < s
->num_irq
) {
369 gic_set_pending_private(&s
->gic
, 0, value
& 0x1ff);
373 qemu_log_mask(LOG_GUEST_ERROR
,
374 "NVIC: Bad write offset 0x%x\n", offset
);
378 static uint64_t nvic_sysreg_read(void *opaque
, hwaddr addr
,
381 nvic_state
*s
= (nvic_state
*)opaque
;
382 uint32_t offset
= addr
;
387 case 0xd18 ... 0xd23: /* System Handler Priority. */
389 for (i
= 0; i
< size
; i
++) {
390 val
|= s
->gic
.priority1
[(offset
- 0xd14) + i
][0] << (i
* 8);
393 case 0xfe0 ... 0xfff: /* ID. */
397 return nvic_id
[(offset
- 0xfe0) >> 2];
400 return nvic_readl(s
, offset
);
402 qemu_log_mask(LOG_GUEST_ERROR
,
403 "NVIC: Bad read of size %d at offset 0x%x\n", size
, offset
);
407 static void nvic_sysreg_write(void *opaque
, hwaddr addr
,
408 uint64_t value
, unsigned size
)
410 nvic_state
*s
= (nvic_state
*)opaque
;
411 uint32_t offset
= addr
;
415 case 0xd18 ... 0xd23: /* System Handler Priority. */
416 for (i
= 0; i
< size
; i
++) {
417 s
->gic
.priority1
[(offset
- 0xd14) + i
][0] =
418 (value
>> (i
* 8)) & 0xff;
424 nvic_writel(s
, offset
, value
);
427 qemu_log_mask(LOG_GUEST_ERROR
,
428 "NVIC: Bad write of size %d at offset 0x%x\n", size
, offset
);
431 static const MemoryRegionOps nvic_sysreg_ops
= {
432 .read
= nvic_sysreg_read
,
433 .write
= nvic_sysreg_write
,
434 .endianness
= DEVICE_NATIVE_ENDIAN
,
437 static const VMStateDescription vmstate_nvic
= {
438 .name
= "armv7m_nvic",
440 .minimum_version_id
= 1,
441 .minimum_version_id_old
= 1,
442 .fields
= (VMStateField
[]) {
443 VMSTATE_UINT32(systick
.control
, nvic_state
),
444 VMSTATE_UINT32(systick
.reload
, nvic_state
),
445 VMSTATE_INT64(systick
.tick
, nvic_state
),
446 VMSTATE_TIMER(systick
.timer
, nvic_state
),
447 VMSTATE_END_OF_LIST()
451 static void armv7m_nvic_reset(DeviceState
*dev
)
453 nvic_state
*s
= NVIC(dev
);
454 NVICClass
*nc
= NVIC_GET_CLASS(s
);
455 nc
->parent_reset(dev
);
456 /* Common GIC reset resets to disabled; the NVIC doesn't have
457 * per-CPU interfaces so mark our non-existent CPU interface
458 * as enabled by default, and with a priority mask which allows
459 * all interrupts through.
461 s
->gic
.cpu_enabled
[0] = 1;
462 s
->gic
.priority_mask
[0] = 0x100;
463 /* The NVIC as a whole is always enabled. */
468 static void armv7m_nvic_realize(DeviceState
*dev
, Error
**errp
)
470 nvic_state
*s
= NVIC(dev
);
471 NVICClass
*nc
= NVIC_GET_CLASS(s
);
473 /* The NVIC always has only one CPU */
475 /* Tell the common code we're an NVIC */
476 s
->gic
.revision
= 0xffffffff;
477 s
->num_irq
= s
->gic
.num_irq
;
478 nc
->parent_realize(dev
, errp
);
479 if (error_is_set(errp
)) {
482 gic_init_irqs_and_distributor(&s
->gic
, s
->num_irq
);
483 /* The NVIC and system controller register area looks like this:
484 * 0..0xff : system control registers, including systick
485 * 0x100..0xcff : GIC-like registers
486 * 0xd00..0xfff : system control registers
487 * We use overlaying to put the GIC like registers
488 * over the top of the system control register region.
490 memory_region_init(&s
->container
, "nvic", 0x1000);
491 /* The system register region goes at the bottom of the priority
492 * stack as it covers the whole page.
494 memory_region_init_io(&s
->sysregmem
, &nvic_sysreg_ops
, s
,
495 "nvic_sysregs", 0x1000);
496 memory_region_add_subregion(&s
->container
, 0, &s
->sysregmem
);
497 /* Alias the GIC region so we can get only the section of it
498 * we need, and layer it on top of the system register region.
500 memory_region_init_alias(&s
->gic_iomem_alias
, "nvic-gic", &s
->gic
.iomem
,
502 memory_region_add_subregion_overlap(&s
->container
, 0x100,
503 &s
->gic_iomem_alias
, 1);
504 /* Map the whole thing into system memory at the location required
505 * by the v7M architecture.
507 memory_region_add_subregion(get_system_memory(), 0xe000e000, &s
->container
);
508 s
->systick
.timer
= qemu_new_timer_ns(vm_clock
, systick_timer_tick
, s
);
511 static void armv7m_nvic_instance_init(Object
*obj
)
513 /* We have a different default value for the num-irq property
514 * than our superclass. This function runs after qdev init
515 * has set the defaults from the Property array and before
516 * any user-specified property setting, so just modify the
517 * value in the GICState struct.
519 GICState
*s
= ARM_GIC_COMMON(obj
);
520 /* The ARM v7m may have anything from 0 to 496 external interrupt
521 * IRQ lines. We default to 64. Other boards may differ and should
522 * set the num-irq property appropriately.
527 static void armv7m_nvic_class_init(ObjectClass
*klass
, void *data
)
529 NVICClass
*nc
= NVIC_CLASS(klass
);
530 DeviceClass
*dc
= DEVICE_CLASS(klass
);
532 nc
->parent_reset
= dc
->reset
;
533 nc
->parent_realize
= dc
->realize
;
534 dc
->vmsd
= &vmstate_nvic
;
535 dc
->reset
= armv7m_nvic_reset
;
536 dc
->realize
= armv7m_nvic_realize
;
539 static const TypeInfo armv7m_nvic_info
= {
541 .parent
= TYPE_ARM_GIC_COMMON
,
542 .instance_init
= armv7m_nvic_instance_init
,
543 .instance_size
= sizeof(nvic_state
),
544 .class_init
= armv7m_nvic_class_init
,
545 .class_size
= sizeof(NVICClass
),
548 static void armv7m_nvic_register_types(void)
550 type_register_static(&armv7m_nvic_info
);
553 type_init(armv7m_nvic_register_types
)