xref: /openbmc/qemu/hw/intc/bcm2836_control.c (revision b097ba37)
1 /*
2  * Rasperry Pi 2 emulation ARM control logic module.
3  * Copyright (c) 2015, Microsoft
4  * Written by Andrew Baumann
5  *
6  * Based on bcm2835_ic.c (Raspberry Pi emulation) (c) 2012 Gregory Estrade
7  * This code is licensed under the GNU GPLv2 and later.
8  *
9  * At present, only implements interrupt routing, and mailboxes (i.e.,
10  * not PMU interrupt, or AXI counters).
11  *
12  * ARM Local Timer IRQ Copyright (c) 2019. Zoltán Baldaszti
13  *
14  * Ref:
15  * https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2836/QA7_rev3.4.pdf
16  */
17 
18 #include "qemu/osdep.h"
19 #include "hw/intc/bcm2836_control.h"
20 #include "qemu/log.h"
21 
22 #define REG_GPU_ROUTE           0x0c
23 #define REG_LOCALTIMERROUTING   0x24
24 #define REG_LOCALTIMERCONTROL   0x34
25 #define REG_LOCALTIMERACK       0x38
26 #define REG_TIMERCONTROL        0x40
27 #define REG_MBOXCONTROL         0x50
28 #define REG_IRQSRC              0x60
29 #define REG_FIQSRC              0x70
30 #define REG_MBOX0_WR            0x80
31 #define REG_MBOX0_RDCLR         0xc0
32 #define REG_LIMIT              0x100
33 
34 #define IRQ_BIT(cntrl, num) (((cntrl) & (1 << (num))) != 0)
35 #define FIQ_BIT(cntrl, num) (((cntrl) & (1 << ((num) + 4))) != 0)
36 
37 #define IRQ_CNTPSIRQ    0
38 #define IRQ_CNTPNSIRQ   1
39 #define IRQ_CNTHPIRQ    2
40 #define IRQ_CNTVIRQ     3
41 #define IRQ_MAILBOX0    4
42 #define IRQ_MAILBOX1    5
43 #define IRQ_MAILBOX2    6
44 #define IRQ_MAILBOX3    7
45 #define IRQ_GPU         8
46 #define IRQ_PMU         9
47 #define IRQ_AXI         10
48 #define IRQ_TIMER       11
49 #define IRQ_MAX         IRQ_TIMER
50 
51 #define LOCALTIMER_FREQ      38400000
52 #define LOCALTIMER_INTFLAG   (1 << 31)
53 #define LOCALTIMER_RELOAD    (1 << 30)
54 #define LOCALTIMER_INTENABLE (1 << 29)
55 #define LOCALTIMER_ENABLE    (1 << 28)
56 #define LOCALTIMER_VALUE(x)  ((x) & 0xfffffff)
57 
58 static void deliver_local(BCM2836ControlState *s, uint8_t core, uint8_t irq,
59                           uint32_t controlreg, uint8_t controlidx)
60 {
61     if (FIQ_BIT(controlreg, controlidx)) {
62         /* deliver a FIQ */
63         s->fiqsrc[core] |= (uint32_t)1 << irq;
64     } else if (IRQ_BIT(controlreg, controlidx)) {
65         /* deliver an IRQ */
66         s->irqsrc[core] |= (uint32_t)1 << irq;
67     } else {
68         /* the interrupt is masked */
69     }
70 }
71 
72 /* Update interrupts.  */
73 static void bcm2836_control_update(BCM2836ControlState *s)
74 {
75     int i, j;
76 
77     /* reset pending IRQs/FIQs */
78     for (i = 0; i < BCM2836_NCORES; i++) {
79         s->irqsrc[i] = s->fiqsrc[i] = 0;
80     }
81 
82     /* apply routing logic, update status regs */
83     if (s->gpu_irq) {
84         assert(s->route_gpu_irq < BCM2836_NCORES);
85         s->irqsrc[s->route_gpu_irq] |= (uint32_t)1 << IRQ_GPU;
86     }
87 
88     if (s->gpu_fiq) {
89         assert(s->route_gpu_fiq < BCM2836_NCORES);
90         s->fiqsrc[s->route_gpu_fiq] |= (uint32_t)1 << IRQ_GPU;
91     }
92 
93     /*
94      * handle the control module 'local timer' interrupt for one of the
95      * cores' IRQ/FIQ;  this is distinct from the per-CPU timer
96      * interrupts handled below.
97      */
98     if ((s->local_timer_control & LOCALTIMER_INTENABLE) &&
99         (s->local_timer_control & LOCALTIMER_INTFLAG)) {
100         if (s->route_localtimer & 4) {
101             s->fiqsrc[(s->route_localtimer & 3)] |= (uint32_t)1 << IRQ_TIMER;
102         } else {
103             s->irqsrc[(s->route_localtimer & 3)] |= (uint32_t)1 << IRQ_TIMER;
104         }
105     }
106 
107     for (i = 0; i < BCM2836_NCORES; i++) {
108         /* handle local timer interrupts for this core */
109         if (s->timerirqs[i]) {
110             assert(s->timerirqs[i] < (1 << (IRQ_CNTVIRQ + 1))); /* sane mask? */
111             for (j = 0; j <= IRQ_CNTVIRQ; j++) {
112                 if ((s->timerirqs[i] & (1 << j)) != 0) {
113                     /* local interrupt j is set */
114                     deliver_local(s, i, j, s->timercontrol[i], j);
115                 }
116             }
117         }
118 
119         /* handle mailboxes for this core */
120         for (j = 0; j < BCM2836_MBPERCORE; j++) {
121             if (s->mailboxes[i * BCM2836_MBPERCORE + j] != 0) {
122                 /* mailbox j is set */
123                 deliver_local(s, i, j + IRQ_MAILBOX0, s->mailboxcontrol[i], j);
124             }
125         }
126     }
127 
128     /* call set_irq appropriately for each output */
129     for (i = 0; i < BCM2836_NCORES; i++) {
130         qemu_set_irq(s->irq[i], s->irqsrc[i] != 0);
131         qemu_set_irq(s->fiq[i], s->fiqsrc[i] != 0);
132     }
133 }
134 
135 static void bcm2836_control_set_local_irq(void *opaque, int core, int local_irq,
136                                           int level)
137 {
138     BCM2836ControlState *s = opaque;
139 
140     assert(core >= 0 && core < BCM2836_NCORES);
141     assert(local_irq >= 0 && local_irq <= IRQ_CNTVIRQ);
142 
143     s->timerirqs[core] = deposit32(s->timerirqs[core], local_irq, 1, !!level);
144 
145     bcm2836_control_update(s);
146 }
147 
148 /* XXX: the following wrapper functions are a kludgy workaround,
149  * needed because I can't seem to pass useful information in the "irq"
150  * parameter when using named interrupts. Feel free to clean this up!
151  */
152 
153 static void bcm2836_control_set_local_irq0(void *opaque, int core, int level)
154 {
155     bcm2836_control_set_local_irq(opaque, core, 0, level);
156 }
157 
158 static void bcm2836_control_set_local_irq1(void *opaque, int core, int level)
159 {
160     bcm2836_control_set_local_irq(opaque, core, 1, level);
161 }
162 
163 static void bcm2836_control_set_local_irq2(void *opaque, int core, int level)
164 {
165     bcm2836_control_set_local_irq(opaque, core, 2, level);
166 }
167 
168 static void bcm2836_control_set_local_irq3(void *opaque, int core, int level)
169 {
170     bcm2836_control_set_local_irq(opaque, core, 3, level);
171 }
172 
173 static void bcm2836_control_set_gpu_irq(void *opaque, int irq, int level)
174 {
175     BCM2836ControlState *s = opaque;
176 
177     s->gpu_irq = level;
178 
179     bcm2836_control_update(s);
180 }
181 
182 static void bcm2836_control_set_gpu_fiq(void *opaque, int irq, int level)
183 {
184     BCM2836ControlState *s = opaque;
185 
186     s->gpu_fiq = level;
187 
188     bcm2836_control_update(s);
189 }
190 
191 static void bcm2836_control_local_timer_set_next(void *opaque)
192 {
193     BCM2836ControlState *s = opaque;
194     uint64_t next_event;
195 
196     assert(LOCALTIMER_VALUE(s->local_timer_control) > 0);
197 
198     next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
199         muldiv64(LOCALTIMER_VALUE(s->local_timer_control),
200             NANOSECONDS_PER_SECOND, LOCALTIMER_FREQ);
201     timer_mod(&s->timer, next_event);
202 }
203 
204 static void bcm2836_control_local_timer_tick(void *opaque)
205 {
206     BCM2836ControlState *s = opaque;
207 
208     bcm2836_control_local_timer_set_next(s);
209 
210     s->local_timer_control |= LOCALTIMER_INTFLAG;
211     bcm2836_control_update(s);
212 }
213 
214 static void bcm2836_control_local_timer_control(void *opaque, uint32_t val)
215 {
216     BCM2836ControlState *s = opaque;
217 
218     s->local_timer_control = val;
219     if (val & LOCALTIMER_ENABLE) {
220         bcm2836_control_local_timer_set_next(s);
221     } else {
222         timer_del(&s->timer);
223     }
224 }
225 
226 static void bcm2836_control_local_timer_ack(void *opaque, uint32_t val)
227 {
228     BCM2836ControlState *s = opaque;
229 
230     if (val & LOCALTIMER_INTFLAG) {
231         s->local_timer_control &= ~LOCALTIMER_INTFLAG;
232     }
233     if ((val & LOCALTIMER_RELOAD) &&
234         (s->local_timer_control & LOCALTIMER_ENABLE)) {
235             bcm2836_control_local_timer_set_next(s);
236     }
237 }
238 
239 static uint64_t bcm2836_control_read(void *opaque, hwaddr offset, unsigned size)
240 {
241     BCM2836ControlState *s = opaque;
242 
243     if (offset == REG_GPU_ROUTE) {
244         assert(s->route_gpu_fiq < BCM2836_NCORES
245                && s->route_gpu_irq < BCM2836_NCORES);
246         return ((uint32_t)s->route_gpu_fiq << 2) | s->route_gpu_irq;
247     } else if (offset == REG_LOCALTIMERROUTING) {
248         return s->route_localtimer;
249     } else if (offset == REG_LOCALTIMERCONTROL) {
250         return s->local_timer_control;
251     } else if (offset == REG_LOCALTIMERACK) {
252         return 0;
253     } else if (offset >= REG_TIMERCONTROL && offset < REG_MBOXCONTROL) {
254         return s->timercontrol[(offset - REG_TIMERCONTROL) >> 2];
255     } else if (offset >= REG_MBOXCONTROL && offset < REG_IRQSRC) {
256         return s->mailboxcontrol[(offset - REG_MBOXCONTROL) >> 2];
257     } else if (offset >= REG_IRQSRC && offset < REG_FIQSRC) {
258         return s->irqsrc[(offset - REG_IRQSRC) >> 2];
259     } else if (offset >= REG_FIQSRC && offset < REG_MBOX0_WR) {
260         return s->fiqsrc[(offset - REG_FIQSRC) >> 2];
261     } else if (offset >= REG_MBOX0_RDCLR && offset < REG_LIMIT) {
262         return s->mailboxes[(offset - REG_MBOX0_RDCLR) >> 2];
263     } else {
264         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
265                       __func__, offset);
266         return 0;
267     }
268 }
269 
270 static void bcm2836_control_write(void *opaque, hwaddr offset,
271                                   uint64_t val, unsigned size)
272 {
273     BCM2836ControlState *s = opaque;
274 
275     if (offset == REG_GPU_ROUTE) {
276         s->route_gpu_irq = val & 0x3;
277         s->route_gpu_fiq = (val >> 2) & 0x3;
278     } else if (offset == REG_LOCALTIMERROUTING) {
279         s->route_localtimer = val & 7;
280     } else if (offset == REG_LOCALTIMERCONTROL) {
281         bcm2836_control_local_timer_control(s, val);
282     } else if (offset == REG_LOCALTIMERACK) {
283         bcm2836_control_local_timer_ack(s, val);
284     } else if (offset >= REG_TIMERCONTROL && offset < REG_MBOXCONTROL) {
285         s->timercontrol[(offset - REG_TIMERCONTROL) >> 2] = val & 0xff;
286     } else if (offset >= REG_MBOXCONTROL && offset < REG_IRQSRC) {
287         s->mailboxcontrol[(offset - REG_MBOXCONTROL) >> 2] = val & 0xff;
288     } else if (offset >= REG_MBOX0_WR && offset < REG_MBOX0_RDCLR) {
289         s->mailboxes[(offset - REG_MBOX0_WR) >> 2] |= val;
290     } else if (offset >= REG_MBOX0_RDCLR && offset < REG_LIMIT) {
291         s->mailboxes[(offset - REG_MBOX0_RDCLR) >> 2] &= ~val;
292     } else {
293         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
294                       __func__, offset);
295         return;
296     }
297 
298     bcm2836_control_update(s);
299 }
300 
301 static const MemoryRegionOps bcm2836_control_ops = {
302     .read = bcm2836_control_read,
303     .write = bcm2836_control_write,
304     .endianness = DEVICE_NATIVE_ENDIAN,
305     .valid.min_access_size = 4,
306     .valid.max_access_size = 4,
307 };
308 
309 static void bcm2836_control_reset(DeviceState *d)
310 {
311     BCM2836ControlState *s = BCM2836_CONTROL(d);
312     int i;
313 
314     s->route_gpu_irq = s->route_gpu_fiq = 0;
315 
316     timer_del(&s->timer);
317     s->route_localtimer = 0;
318     s->local_timer_control = 0;
319 
320     for (i = 0; i < BCM2836_NCORES; i++) {
321         s->timercontrol[i] = 0;
322         s->mailboxcontrol[i] = 0;
323     }
324 
325     for (i = 0; i < BCM2836_NCORES * BCM2836_MBPERCORE; i++) {
326         s->mailboxes[i] = 0;
327     }
328 }
329 
330 static void bcm2836_control_init(Object *obj)
331 {
332     BCM2836ControlState *s = BCM2836_CONTROL(obj);
333     DeviceState *dev = DEVICE(obj);
334 
335     memory_region_init_io(&s->iomem, obj, &bcm2836_control_ops, s,
336                           TYPE_BCM2836_CONTROL, REG_LIMIT);
337     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
338 
339     /* inputs from each CPU core */
340     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq0, "cntpsirq",
341                             BCM2836_NCORES);
342     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq1, "cntpnsirq",
343                             BCM2836_NCORES);
344     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq2, "cnthpirq",
345                             BCM2836_NCORES);
346     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq3, "cntvirq",
347                             BCM2836_NCORES);
348 
349     /* IRQ and FIQ inputs from upstream bcm2835 controller */
350     qdev_init_gpio_in_named(dev, bcm2836_control_set_gpu_irq, "gpu-irq", 1);
351     qdev_init_gpio_in_named(dev, bcm2836_control_set_gpu_fiq, "gpu-fiq", 1);
352 
353     /* outputs to CPU cores */
354     qdev_init_gpio_out_named(dev, s->irq, "irq", BCM2836_NCORES);
355     qdev_init_gpio_out_named(dev, s->fiq, "fiq", BCM2836_NCORES);
356 
357     /* create a qemu virtual timer */
358     timer_init_ns(&s->timer, QEMU_CLOCK_VIRTUAL,
359                   bcm2836_control_local_timer_tick, s);
360 }
361 
362 static const VMStateDescription vmstate_bcm2836_control = {
363     .name = TYPE_BCM2836_CONTROL,
364     .version_id = 2,
365     .minimum_version_id = 1,
366     .fields = (VMStateField[]) {
367         VMSTATE_UINT32_ARRAY(mailboxes, BCM2836ControlState,
368                              BCM2836_NCORES * BCM2836_MBPERCORE),
369         VMSTATE_UINT8(route_gpu_irq, BCM2836ControlState),
370         VMSTATE_UINT8(route_gpu_fiq, BCM2836ControlState),
371         VMSTATE_UINT32_ARRAY(timercontrol, BCM2836ControlState, BCM2836_NCORES),
372         VMSTATE_UINT32_ARRAY(mailboxcontrol, BCM2836ControlState,
373                              BCM2836_NCORES),
374         VMSTATE_TIMER_V(timer, BCM2836ControlState, 2),
375         VMSTATE_UINT32_V(local_timer_control, BCM2836ControlState, 2),
376         VMSTATE_UINT8_V(route_localtimer, BCM2836ControlState, 2),
377         VMSTATE_END_OF_LIST()
378     }
379 };
380 
381 static void bcm2836_control_class_init(ObjectClass *klass, void *data)
382 {
383     DeviceClass *dc = DEVICE_CLASS(klass);
384 
385     dc->reset = bcm2836_control_reset;
386     dc->vmsd = &vmstate_bcm2836_control;
387 }
388 
389 static TypeInfo bcm2836_control_info = {
390     .name          = TYPE_BCM2836_CONTROL,
391     .parent        = TYPE_SYS_BUS_DEVICE,
392     .instance_size = sizeof(BCM2836ControlState),
393     .class_init    = bcm2836_control_class_init,
394     .instance_init = bcm2836_control_init,
395 };
396 
397 static void bcm2836_control_register_types(void)
398 {
399     type_register_static(&bcm2836_control_info);
400 }
401 
402 type_init(bcm2836_control_register_types)
403