xref: /openbmc/qemu/hw/intc/bcm2836_control.c (revision c964b660)
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 local timer, PMU interrupt, or AXI counters).
11  *
12  * Ref:
13  * https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2836/QA7_rev3.4.pdf
14  */
15 
16 #include "qemu/osdep.h"
17 #include "hw/intc/bcm2836_control.h"
18 
19 #define REG_GPU_ROUTE           0x0c
20 #define REG_TIMERCONTROL        0x40
21 #define REG_MBOXCONTROL         0x50
22 #define REG_IRQSRC              0x60
23 #define REG_FIQSRC              0x70
24 #define REG_MBOX0_WR            0x80
25 #define REG_MBOX0_RDCLR         0xc0
26 #define REG_LIMIT              0x100
27 
28 #define IRQ_BIT(cntrl, num) (((cntrl) & (1 << (num))) != 0)
29 #define FIQ_BIT(cntrl, num) (((cntrl) & (1 << ((num) + 4))) != 0)
30 
31 #define IRQ_CNTPSIRQ    0
32 #define IRQ_CNTPNSIRQ   1
33 #define IRQ_CNTHPIRQ    2
34 #define IRQ_CNTVIRQ     3
35 #define IRQ_MAILBOX0    4
36 #define IRQ_MAILBOX1    5
37 #define IRQ_MAILBOX2    6
38 #define IRQ_MAILBOX3    7
39 #define IRQ_GPU         8
40 #define IRQ_PMU         9
41 #define IRQ_AXI         10
42 #define IRQ_TIMER       11
43 #define IRQ_MAX         IRQ_TIMER
44 
45 static void deliver_local(BCM2836ControlState *s, uint8_t core, uint8_t irq,
46                           uint32_t controlreg, uint8_t controlidx)
47 {
48     if (FIQ_BIT(controlreg, controlidx)) {
49         /* deliver a FIQ */
50         s->fiqsrc[core] |= (uint32_t)1 << irq;
51     } else if (IRQ_BIT(controlreg, controlidx)) {
52         /* deliver an IRQ */
53         s->irqsrc[core] |= (uint32_t)1 << irq;
54     } else {
55         /* the interrupt is masked */
56     }
57 }
58 
59 /* Update interrupts.  */
60 static void bcm2836_control_update(BCM2836ControlState *s)
61 {
62     int i, j;
63 
64     /* reset pending IRQs/FIQs */
65     for (i = 0; i < BCM2836_NCORES; i++) {
66         s->irqsrc[i] = s->fiqsrc[i] = 0;
67     }
68 
69     /* apply routing logic, update status regs */
70     if (s->gpu_irq) {
71         assert(s->route_gpu_irq < BCM2836_NCORES);
72         s->irqsrc[s->route_gpu_irq] |= (uint32_t)1 << IRQ_GPU;
73     }
74 
75     if (s->gpu_fiq) {
76         assert(s->route_gpu_fiq < BCM2836_NCORES);
77         s->fiqsrc[s->route_gpu_fiq] |= (uint32_t)1 << IRQ_GPU;
78     }
79 
80     for (i = 0; i < BCM2836_NCORES; i++) {
81         /* handle local timer interrupts for this core */
82         if (s->timerirqs[i]) {
83             assert(s->timerirqs[i] < (1 << (IRQ_CNTVIRQ + 1))); /* sane mask? */
84             for (j = 0; j <= IRQ_CNTVIRQ; j++) {
85                 if ((s->timerirqs[i] & (1 << j)) != 0) {
86                     /* local interrupt j is set */
87                     deliver_local(s, i, j, s->timercontrol[i], j);
88                 }
89             }
90         }
91 
92         /* handle mailboxes for this core */
93         for (j = 0; j < BCM2836_MBPERCORE; j++) {
94             if (s->mailboxes[i * BCM2836_MBPERCORE + j] != 0) {
95                 /* mailbox j is set */
96                 deliver_local(s, i, j + IRQ_MAILBOX0, s->mailboxcontrol[i], j);
97             }
98         }
99     }
100 
101     /* call set_irq appropriately for each output */
102     for (i = 0; i < BCM2836_NCORES; i++) {
103         qemu_set_irq(s->irq[i], s->irqsrc[i] != 0);
104         qemu_set_irq(s->fiq[i], s->fiqsrc[i] != 0);
105     }
106 }
107 
108 static void bcm2836_control_set_local_irq(void *opaque, int core, int local_irq,
109                                           int level)
110 {
111     BCM2836ControlState *s = opaque;
112 
113     assert(core >= 0 && core < BCM2836_NCORES);
114     assert(local_irq >= 0 && local_irq <= IRQ_CNTVIRQ);
115 
116     s->timerirqs[core] = deposit32(s->timerirqs[core], local_irq, 1, !!level);
117 
118     bcm2836_control_update(s);
119 }
120 
121 /* XXX: the following wrapper functions are a kludgy workaround,
122  * needed because I can't seem to pass useful information in the "irq"
123  * parameter when using named interrupts. Feel free to clean this up!
124  */
125 
126 static void bcm2836_control_set_local_irq0(void *opaque, int core, int level)
127 {
128     bcm2836_control_set_local_irq(opaque, core, 0, level);
129 }
130 
131 static void bcm2836_control_set_local_irq1(void *opaque, int core, int level)
132 {
133     bcm2836_control_set_local_irq(opaque, core, 1, level);
134 }
135 
136 static void bcm2836_control_set_local_irq2(void *opaque, int core, int level)
137 {
138     bcm2836_control_set_local_irq(opaque, core, 2, level);
139 }
140 
141 static void bcm2836_control_set_local_irq3(void *opaque, int core, int level)
142 {
143     bcm2836_control_set_local_irq(opaque, core, 3, level);
144 }
145 
146 static void bcm2836_control_set_gpu_irq(void *opaque, int irq, int level)
147 {
148     BCM2836ControlState *s = opaque;
149 
150     s->gpu_irq = level;
151 
152     bcm2836_control_update(s);
153 }
154 
155 static void bcm2836_control_set_gpu_fiq(void *opaque, int irq, int level)
156 {
157     BCM2836ControlState *s = opaque;
158 
159     s->gpu_fiq = level;
160 
161     bcm2836_control_update(s);
162 }
163 
164 static uint64_t bcm2836_control_read(void *opaque, hwaddr offset, unsigned size)
165 {
166     BCM2836ControlState *s = opaque;
167 
168     if (offset == REG_GPU_ROUTE) {
169         assert(s->route_gpu_fiq < BCM2836_NCORES
170                && s->route_gpu_irq < BCM2836_NCORES);
171         return ((uint32_t)s->route_gpu_fiq << 2) | s->route_gpu_irq;
172     } else if (offset >= REG_TIMERCONTROL && offset < REG_MBOXCONTROL) {
173         return s->timercontrol[(offset - REG_TIMERCONTROL) >> 2];
174     } else if (offset >= REG_MBOXCONTROL && offset < REG_IRQSRC) {
175         return s->mailboxcontrol[(offset - REG_MBOXCONTROL) >> 2];
176     } else if (offset >= REG_IRQSRC && offset < REG_FIQSRC) {
177         return s->irqsrc[(offset - REG_IRQSRC) >> 2];
178     } else if (offset >= REG_FIQSRC && offset < REG_MBOX0_WR) {
179         return s->fiqsrc[(offset - REG_FIQSRC) >> 2];
180     } else if (offset >= REG_MBOX0_RDCLR && offset < REG_LIMIT) {
181         return s->mailboxes[(offset - REG_MBOX0_RDCLR) >> 2];
182     } else {
183         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
184                       __func__, offset);
185         return 0;
186     }
187 }
188 
189 static void bcm2836_control_write(void *opaque, hwaddr offset,
190                                   uint64_t val, unsigned size)
191 {
192     BCM2836ControlState *s = opaque;
193 
194     if (offset == REG_GPU_ROUTE) {
195         s->route_gpu_irq = val & 0x3;
196         s->route_gpu_fiq = (val >> 2) & 0x3;
197     } else if (offset >= REG_TIMERCONTROL && offset < REG_MBOXCONTROL) {
198         s->timercontrol[(offset - REG_TIMERCONTROL) >> 2] = val & 0xff;
199     } else if (offset >= REG_MBOXCONTROL && offset < REG_IRQSRC) {
200         s->mailboxcontrol[(offset - REG_MBOXCONTROL) >> 2] = val & 0xff;
201     } else if (offset >= REG_MBOX0_WR && offset < REG_MBOX0_RDCLR) {
202         s->mailboxes[(offset - REG_MBOX0_WR) >> 2] |= val;
203     } else if (offset >= REG_MBOX0_RDCLR && offset < REG_LIMIT) {
204         s->mailboxes[(offset - REG_MBOX0_RDCLR) >> 2] &= ~val;
205     } else {
206         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
207                       __func__, offset);
208         return;
209     }
210 
211     bcm2836_control_update(s);
212 }
213 
214 static const MemoryRegionOps bcm2836_control_ops = {
215     .read = bcm2836_control_read,
216     .write = bcm2836_control_write,
217     .endianness = DEVICE_NATIVE_ENDIAN,
218     .valid.min_access_size = 4,
219     .valid.max_access_size = 4,
220 };
221 
222 static void bcm2836_control_reset(DeviceState *d)
223 {
224     BCM2836ControlState *s = BCM2836_CONTROL(d);
225     int i;
226 
227     s->route_gpu_irq = s->route_gpu_fiq = 0;
228 
229     for (i = 0; i < BCM2836_NCORES; i++) {
230         s->timercontrol[i] = 0;
231         s->mailboxcontrol[i] = 0;
232     }
233 
234     for (i = 0; i < BCM2836_NCORES * BCM2836_MBPERCORE; i++) {
235         s->mailboxes[i] = 0;
236     }
237 }
238 
239 static void bcm2836_control_init(Object *obj)
240 {
241     BCM2836ControlState *s = BCM2836_CONTROL(obj);
242     DeviceState *dev = DEVICE(obj);
243 
244     memory_region_init_io(&s->iomem, obj, &bcm2836_control_ops, s,
245                           TYPE_BCM2836_CONTROL, REG_LIMIT);
246     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
247 
248     /* inputs from each CPU core */
249     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq0, "cntpsirq",
250                             BCM2836_NCORES);
251     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq1, "cntpnsirq",
252                             BCM2836_NCORES);
253     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq2, "cnthpirq",
254                             BCM2836_NCORES);
255     qdev_init_gpio_in_named(dev, bcm2836_control_set_local_irq3, "cntvirq",
256                             BCM2836_NCORES);
257 
258     /* IRQ and FIQ inputs from upstream bcm2835 controller */
259     qdev_init_gpio_in_named(dev, bcm2836_control_set_gpu_irq, "gpu-irq", 1);
260     qdev_init_gpio_in_named(dev, bcm2836_control_set_gpu_fiq, "gpu-fiq", 1);
261 
262     /* outputs to CPU cores */
263     qdev_init_gpio_out_named(dev, s->irq, "irq", BCM2836_NCORES);
264     qdev_init_gpio_out_named(dev, s->fiq, "fiq", BCM2836_NCORES);
265 }
266 
267 static const VMStateDescription vmstate_bcm2836_control = {
268     .name = TYPE_BCM2836_CONTROL,
269     .version_id = 1,
270     .minimum_version_id = 1,
271     .fields = (VMStateField[]) {
272         VMSTATE_UINT32_ARRAY(mailboxes, BCM2836ControlState,
273                              BCM2836_NCORES * BCM2836_MBPERCORE),
274         VMSTATE_UINT8(route_gpu_irq, BCM2836ControlState),
275         VMSTATE_UINT8(route_gpu_fiq, BCM2836ControlState),
276         VMSTATE_UINT32_ARRAY(timercontrol, BCM2836ControlState, BCM2836_NCORES),
277         VMSTATE_UINT32_ARRAY(mailboxcontrol, BCM2836ControlState,
278                              BCM2836_NCORES),
279         VMSTATE_END_OF_LIST()
280     }
281 };
282 
283 static void bcm2836_control_class_init(ObjectClass *klass, void *data)
284 {
285     DeviceClass *dc = DEVICE_CLASS(klass);
286 
287     dc->reset = bcm2836_control_reset;
288     dc->vmsd = &vmstate_bcm2836_control;
289 }
290 
291 static TypeInfo bcm2836_control_info = {
292     .name          = TYPE_BCM2836_CONTROL,
293     .parent        = TYPE_SYS_BUS_DEVICE,
294     .instance_size = sizeof(BCM2836ControlState),
295     .class_init    = bcm2836_control_class_init,
296     .instance_init = bcm2836_control_init,
297 };
298 
299 static void bcm2836_control_register_types(void)
300 {
301     type_register_static(&bcm2836_control_info);
302 }
303 
304 type_init(bcm2836_control_register_types)
305