xref: /openbmc/qemu/hw/intc/bcm2836_control.c (revision 3d9569b8)
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 #include "qemu/module.h"
22 
23 #define REG_GPU_ROUTE           0x0c
24 #define REG_LOCALTIMERROUTING   0x24
25 #define REG_LOCALTIMERCONTROL   0x34
26 #define REG_LOCALTIMERACK       0x38
27 #define REG_TIMERCONTROL        0x40
28 #define REG_MBOXCONTROL         0x50
29 #define REG_IRQSRC              0x60
30 #define REG_FIQSRC              0x70
31 #define REG_MBOX0_WR            0x80
32 #define REG_MBOX0_RDCLR         0xc0
33 #define REG_LIMIT              0x100
34 
35 #define IRQ_BIT(cntrl, num) (((cntrl) & (1 << (num))) != 0)
36 #define FIQ_BIT(cntrl, num) (((cntrl) & (1 << ((num) + 4))) != 0)
37 
38 #define IRQ_CNTPSIRQ    0
39 #define IRQ_CNTPNSIRQ   1
40 #define IRQ_CNTHPIRQ    2
41 #define IRQ_CNTVIRQ     3
42 #define IRQ_MAILBOX0    4
43 #define IRQ_MAILBOX1    5
44 #define IRQ_MAILBOX2    6
45 #define IRQ_MAILBOX3    7
46 #define IRQ_GPU         8
47 #define IRQ_PMU         9
48 #define IRQ_AXI         10
49 #define IRQ_TIMER       11
50 #define IRQ_MAX         IRQ_TIMER
51 
52 #define LOCALTIMER_FREQ      38400000
53 #define LOCALTIMER_INTFLAG   (1 << 31)
54 #define LOCALTIMER_RELOAD    (1 << 30)
55 #define LOCALTIMER_INTENABLE (1 << 29)
56 #define LOCALTIMER_ENABLE    (1 << 28)
57 #define LOCALTIMER_VALUE(x)  ((x) & 0xfffffff)
58 
59 static void deliver_local(BCM2836ControlState *s, uint8_t core, uint8_t irq,
60                           uint32_t controlreg, uint8_t controlidx)
61 {
62     if (FIQ_BIT(controlreg, controlidx)) {
63         /* deliver a FIQ */
64         s->fiqsrc[core] |= (uint32_t)1 << irq;
65     } else if (IRQ_BIT(controlreg, controlidx)) {
66         /* deliver an IRQ */
67         s->irqsrc[core] |= (uint32_t)1 << irq;
68     } else {
69         /* the interrupt is masked */
70     }
71 }
72 
73 /* Update interrupts.  */
74 static void bcm2836_control_update(BCM2836ControlState *s)
75 {
76     int i, j;
77 
78     /* reset pending IRQs/FIQs */
79     for (i = 0; i < BCM2836_NCORES; i++) {
80         s->irqsrc[i] = s->fiqsrc[i] = 0;
81     }
82 
83     /* apply routing logic, update status regs */
84     if (s->gpu_irq) {
85         assert(s->route_gpu_irq < BCM2836_NCORES);
86         s->irqsrc[s->route_gpu_irq] |= (uint32_t)1 << IRQ_GPU;
87     }
88 
89     if (s->gpu_fiq) {
90         assert(s->route_gpu_fiq < BCM2836_NCORES);
91         s->fiqsrc[s->route_gpu_fiq] |= (uint32_t)1 << IRQ_GPU;
92     }
93 
94     /*
95      * handle the control module 'local timer' interrupt for one of the
96      * cores' IRQ/FIQ;  this is distinct from the per-CPU timer
97      * interrupts handled below.
98      */
99     if ((s->local_timer_control & LOCALTIMER_INTENABLE) &&
100         (s->local_timer_control & LOCALTIMER_INTFLAG)) {
101         if (s->route_localtimer & 4) {
102             s->fiqsrc[(s->route_localtimer & 3)] |= (uint32_t)1 << IRQ_TIMER;
103         } else {
104             s->irqsrc[(s->route_localtimer & 3)] |= (uint32_t)1 << IRQ_TIMER;
105         }
106     }
107 
108     for (i = 0; i < BCM2836_NCORES; i++) {
109         /* handle local timer interrupts for this core */
110         if (s->timerirqs[i]) {
111             assert(s->timerirqs[i] < (1 << (IRQ_CNTVIRQ + 1))); /* sane mask? */
112             for (j = 0; j <= IRQ_CNTVIRQ; j++) {
113                 if ((s->timerirqs[i] & (1 << j)) != 0) {
114                     /* local interrupt j is set */
115                     deliver_local(s, i, j, s->timercontrol[i], j);
116                 }
117             }
118         }
119 
120         /* handle mailboxes for this core */
121         for (j = 0; j < BCM2836_MBPERCORE; j++) {
122             if (s->mailboxes[i * BCM2836_MBPERCORE + j] != 0) {
123                 /* mailbox j is set */
124                 deliver_local(s, i, j + IRQ_MAILBOX0, s->mailboxcontrol[i], j);
125             }
126         }
127     }
128 
129     /* call set_irq appropriately for each output */
130     for (i = 0; i < BCM2836_NCORES; i++) {
131         qemu_set_irq(s->irq[i], s->irqsrc[i] != 0);
132         qemu_set_irq(s->fiq[i], s->fiqsrc[i] != 0);
133     }
134 }
135 
136 static void bcm2836_control_set_local_irq(void *opaque, int core, int local_irq,
137                                           int level)
138 {
139     BCM2836ControlState *s = opaque;
140 
141     assert(core >= 0 && core < BCM2836_NCORES);
142     assert(local_irq >= 0 && local_irq <= IRQ_CNTVIRQ);
143 
144     s->timerirqs[core] = deposit32(s->timerirqs[core], local_irq, 1, !!level);
145 
146     bcm2836_control_update(s);
147 }
148 
149 /* XXX: the following wrapper functions are a kludgy workaround,
150  * needed because I can't seem to pass useful information in the "irq"
151  * parameter when using named interrupts. Feel free to clean this up!
152  */
153 
154 static void bcm2836_control_set_local_irq0(void *opaque, int core, int level)
155 {
156     bcm2836_control_set_local_irq(opaque, core, 0, level);
157 }
158 
159 static void bcm2836_control_set_local_irq1(void *opaque, int core, int level)
160 {
161     bcm2836_control_set_local_irq(opaque, core, 1, level);
162 }
163 
164 static void bcm2836_control_set_local_irq2(void *opaque, int core, int level)
165 {
166     bcm2836_control_set_local_irq(opaque, core, 2, level);
167 }
168 
169 static void bcm2836_control_set_local_irq3(void *opaque, int core, int level)
170 {
171     bcm2836_control_set_local_irq(opaque, core, 3, level);
172 }
173 
174 static void bcm2836_control_set_gpu_irq(void *opaque, int irq, int level)
175 {
176     BCM2836ControlState *s = opaque;
177 
178     s->gpu_irq = level;
179 
180     bcm2836_control_update(s);
181 }
182 
183 static void bcm2836_control_set_gpu_fiq(void *opaque, int irq, int level)
184 {
185     BCM2836ControlState *s = opaque;
186 
187     s->gpu_fiq = level;
188 
189     bcm2836_control_update(s);
190 }
191 
192 static void bcm2836_control_local_timer_set_next(void *opaque)
193 {
194     BCM2836ControlState *s = opaque;
195     uint64_t next_event;
196 
197     assert(LOCALTIMER_VALUE(s->local_timer_control) > 0);
198 
199     next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
200         muldiv64(LOCALTIMER_VALUE(s->local_timer_control),
201             NANOSECONDS_PER_SECOND, LOCALTIMER_FREQ);
202     timer_mod(&s->timer, next_event);
203 }
204 
205 static void bcm2836_control_local_timer_tick(void *opaque)
206 {
207     BCM2836ControlState *s = opaque;
208 
209     bcm2836_control_local_timer_set_next(s);
210 
211     s->local_timer_control |= LOCALTIMER_INTFLAG;
212     bcm2836_control_update(s);
213 }
214 
215 static void bcm2836_control_local_timer_control(void *opaque, uint32_t val)
216 {
217     BCM2836ControlState *s = opaque;
218 
219     s->local_timer_control = val;
220     if (val & LOCALTIMER_ENABLE) {
221         bcm2836_control_local_timer_set_next(s);
222     } else {
223         timer_del(&s->timer);
224     }
225 }
226 
227 static void bcm2836_control_local_timer_ack(void *opaque, uint32_t val)
228 {
229     BCM2836ControlState *s = opaque;
230 
231     if (val & LOCALTIMER_INTFLAG) {
232         s->local_timer_control &= ~LOCALTIMER_INTFLAG;
233     }
234     if ((val & LOCALTIMER_RELOAD) &&
235         (s->local_timer_control & LOCALTIMER_ENABLE)) {
236             bcm2836_control_local_timer_set_next(s);
237     }
238 }
239 
240 static uint64_t bcm2836_control_read(void *opaque, hwaddr offset, unsigned size)
241 {
242     BCM2836ControlState *s = opaque;
243 
244     if (offset == REG_GPU_ROUTE) {
245         assert(s->route_gpu_fiq < BCM2836_NCORES
246                && s->route_gpu_irq < BCM2836_NCORES);
247         return ((uint32_t)s->route_gpu_fiq << 2) | s->route_gpu_irq;
248     } else if (offset == REG_LOCALTIMERROUTING) {
249         return s->route_localtimer;
250     } else if (offset == REG_LOCALTIMERCONTROL) {
251         return s->local_timer_control;
252     } else if (offset == REG_LOCALTIMERACK) {
253         return 0;
254     } else if (offset >= REG_TIMERCONTROL && offset < REG_MBOXCONTROL) {
255         return s->timercontrol[(offset - REG_TIMERCONTROL) >> 2];
256     } else if (offset >= REG_MBOXCONTROL && offset < REG_IRQSRC) {
257         return s->mailboxcontrol[(offset - REG_MBOXCONTROL) >> 2];
258     } else if (offset >= REG_IRQSRC && offset < REG_FIQSRC) {
259         return s->irqsrc[(offset - REG_IRQSRC) >> 2];
260     } else if (offset >= REG_FIQSRC && offset < REG_MBOX0_WR) {
261         return s->fiqsrc[(offset - REG_FIQSRC) >> 2];
262     } else if (offset >= REG_MBOX0_RDCLR && offset < REG_LIMIT) {
263         return s->mailboxes[(offset - REG_MBOX0_RDCLR) >> 2];
264     } else {
265         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
266                       __func__, offset);
267         return 0;
268     }
269 }
270 
271 static void bcm2836_control_write(void *opaque, hwaddr offset,
272                                   uint64_t val, unsigned size)
273 {
274     BCM2836ControlState *s = opaque;
275 
276     if (offset == REG_GPU_ROUTE) {
277         s->route_gpu_irq = val & 0x3;
278         s->route_gpu_fiq = (val >> 2) & 0x3;
279     } else if (offset == REG_LOCALTIMERROUTING) {
280         s->route_localtimer = val & 7;
281     } else if (offset == REG_LOCALTIMERCONTROL) {
282         bcm2836_control_local_timer_control(s, val);
283     } else if (offset == REG_LOCALTIMERACK) {
284         bcm2836_control_local_timer_ack(s, val);
285     } else if (offset >= REG_TIMERCONTROL && offset < REG_MBOXCONTROL) {
286         s->timercontrol[(offset - REG_TIMERCONTROL) >> 2] = val & 0xff;
287     } else if (offset >= REG_MBOXCONTROL && offset < REG_IRQSRC) {
288         s->mailboxcontrol[(offset - REG_MBOXCONTROL) >> 2] = val & 0xff;
289     } else if (offset >= REG_MBOX0_WR && offset < REG_MBOX0_RDCLR) {
290         s->mailboxes[(offset - REG_MBOX0_WR) >> 2] |= val;
291     } else if (offset >= REG_MBOX0_RDCLR && offset < REG_LIMIT) {
292         s->mailboxes[(offset - REG_MBOX0_RDCLR) >> 2] &= ~val;
293     } else {
294         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
295                       __func__, offset);
296         return;
297     }
298 
299     bcm2836_control_update(s);
300 }
301 
302 static const MemoryRegionOps bcm2836_control_ops = {
303     .read = bcm2836_control_read,
304     .write = bcm2836_control_write,
305     .endianness = DEVICE_NATIVE_ENDIAN,
306     .valid.min_access_size = 4,
307     .valid.max_access_size = 4,
308 };
309 
310 static void bcm2836_control_reset(DeviceState *d)
311 {
312     BCM2836ControlState *s = BCM2836_CONTROL(d);
313     int i;
314 
315     s->route_gpu_irq = s->route_gpu_fiq = 0;
316 
317     timer_del(&s->timer);
318     s->route_localtimer = 0;
319     s->local_timer_control = 0;
320 
321     for (i = 0; i < BCM2836_NCORES; i++) {
322         s->timercontrol[i] = 0;
323         s->mailboxcontrol[i] = 0;
324     }
325 
326     for (i = 0; i < BCM2836_NCORES * BCM2836_MBPERCORE; i++) {
327         s->mailboxes[i] = 0;
328     }
329 }
330 
331 static void bcm2836_control_init(Object *obj)
332 {
333     BCM2836ControlState *s = BCM2836_CONTROL(obj);
334     DeviceState *dev = DEVICE(obj);
335 
336     memory_region_init_io(&s->iomem, obj, &bcm2836_control_ops, s,
337                           TYPE_BCM2836_CONTROL, REG_LIMIT);
338     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
339 
340     /* inputs from each CPU core */
341     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq0, "cntpsirq",
342                             BCM2836_NCORES);
343     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq1, "cntpnsirq",
344                             BCM2836_NCORES);
345     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq2, "cnthpirq",
346                             BCM2836_NCORES);
347     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq3, "cntvirq",
348                             BCM2836_NCORES);
349 
350     /* IRQ and FIQ inputs from upstream bcm2835 controller */
351     qdev_init_gpio_in_named(dev, bcm2836_control_set_gpu_irq, "gpu-irq", 1);
352     qdev_init_gpio_in_named(dev, bcm2836_control_set_gpu_fiq, "gpu-fiq", 1);
353 
354     /* outputs to CPU cores */
355     qdev_init_gpio_out_named(dev, s->irq, "irq", BCM2836_NCORES);
356     qdev_init_gpio_out_named(dev, s->fiq, "fiq", BCM2836_NCORES);
357 
358     /* create a qemu virtual timer */
359     timer_init_ns(&s->timer, QEMU_CLOCK_VIRTUAL,
360                   bcm2836_control_local_timer_tick, s);
361 }
362 
363 static const VMStateDescription vmstate_bcm2836_control = {
364     .name = TYPE_BCM2836_CONTROL,
365     .version_id = 2,
366     .minimum_version_id = 1,
367     .fields = (VMStateField[]) {
368         VMSTATE_UINT32_ARRAY(mailboxes, BCM2836ControlState,
369                              BCM2836_NCORES * BCM2836_MBPERCORE),
370         VMSTATE_UINT8(route_gpu_irq, BCM2836ControlState),
371         VMSTATE_UINT8(route_gpu_fiq, BCM2836ControlState),
372         VMSTATE_UINT32_ARRAY(timercontrol, BCM2836ControlState, BCM2836_NCORES),
373         VMSTATE_UINT32_ARRAY(mailboxcontrol, BCM2836ControlState,
374                              BCM2836_NCORES),
375         VMSTATE_TIMER_V(timer, BCM2836ControlState, 2),
376         VMSTATE_UINT32_V(local_timer_control, BCM2836ControlState, 2),
377         VMSTATE_UINT8_V(route_localtimer, BCM2836ControlState, 2),
378         VMSTATE_END_OF_LIST()
379     }
380 };
381 
382 static void bcm2836_control_class_init(ObjectClass *klass, void *data)
383 {
384     DeviceClass *dc = DEVICE_CLASS(klass);
385 
386     dc->reset = bcm2836_control_reset;
387     dc->vmsd = &vmstate_bcm2836_control;
388 }
389 
390 static TypeInfo bcm2836_control_info = {
391     .name          = TYPE_BCM2836_CONTROL,
392     .parent        = TYPE_SYS_BUS_DEVICE,
393     .instance_size = sizeof(BCM2836ControlState),
394     .class_init    = bcm2836_control_class_init,
395     .instance_init = bcm2836_control_init,
396 };
397 
398 static void bcm2836_control_register_types(void)
399 {
400     type_register_static(&bcm2836_control_info);
401 }
402 
403 type_init(bcm2836_control_register_types)
404