xref: /openbmc/qemu/hw/intc/pl190.c (revision 64552b6b)
1 /*
2  * Arm PrimeCell PL190 Vector Interrupt Controller
3  *
4  * Copyright (c) 2006 CodeSourcery.
5  * Written by Paul Brook
6  *
7  * This code is licensed under the GPL.
8  */
9 
10 #include "qemu/osdep.h"
11 #include "hw/irq.h"
12 #include "hw/sysbus.h"
13 #include "qemu/log.h"
14 #include "qemu/module.h"
15 
16 /* The number of virtual priority levels.  16 user vectors plus the
17    unvectored IRQ.  Chained interrupts would require an additional level
18    if implemented.  */
19 
20 #define PL190_NUM_PRIO 17
21 
22 #define TYPE_PL190 "pl190"
23 #define PL190(obj) OBJECT_CHECK(PL190State, (obj), TYPE_PL190)
24 
25 typedef struct PL190State {
26     SysBusDevice parent_obj;
27 
28     MemoryRegion iomem;
29     uint32_t level;
30     uint32_t soft_level;
31     uint32_t irq_enable;
32     uint32_t fiq_select;
33     uint8_t vect_control[16];
34     uint32_t vect_addr[PL190_NUM_PRIO];
35     /* Mask containing interrupts with higher priority than this one.  */
36     uint32_t prio_mask[PL190_NUM_PRIO + 1];
37     int protected;
38     /* Current priority level.  */
39     int priority;
40     int prev_prio[PL190_NUM_PRIO];
41     qemu_irq irq;
42     qemu_irq fiq;
43 } PL190State;
44 
45 static const unsigned char pl190_id[] =
46 { 0x90, 0x11, 0x04, 0x00, 0x0D, 0xf0, 0x05, 0xb1 };
47 
48 static inline uint32_t pl190_irq_level(PL190State *s)
49 {
50     return (s->level | s->soft_level) & s->irq_enable & ~s->fiq_select;
51 }
52 
53 /* Update interrupts.  */
54 static void pl190_update(PL190State *s)
55 {
56     uint32_t level = pl190_irq_level(s);
57     int set;
58 
59     set = (level & s->prio_mask[s->priority]) != 0;
60     qemu_set_irq(s->irq, set);
61     set = ((s->level | s->soft_level) & s->fiq_select) != 0;
62     qemu_set_irq(s->fiq, set);
63 }
64 
65 static void pl190_set_irq(void *opaque, int irq, int level)
66 {
67     PL190State *s = (PL190State *)opaque;
68 
69     if (level)
70         s->level |= 1u << irq;
71     else
72         s->level &= ~(1u << irq);
73     pl190_update(s);
74 }
75 
76 static void pl190_update_vectors(PL190State *s)
77 {
78     uint32_t mask;
79     int i;
80     int n;
81 
82     mask = 0;
83     for (i = 0; i < 16; i++)
84       {
85         s->prio_mask[i] = mask;
86         if (s->vect_control[i] & 0x20)
87           {
88             n = s->vect_control[i] & 0x1f;
89             mask |= 1 << n;
90           }
91       }
92     s->prio_mask[16] = mask;
93     pl190_update(s);
94 }
95 
96 static uint64_t pl190_read(void *opaque, hwaddr offset,
97                            unsigned size)
98 {
99     PL190State *s = (PL190State *)opaque;
100     int i;
101 
102     if (offset >= 0xfe0 && offset < 0x1000) {
103         return pl190_id[(offset - 0xfe0) >> 2];
104     }
105     if (offset >= 0x100 && offset < 0x140) {
106         return s->vect_addr[(offset - 0x100) >> 2];
107     }
108     if (offset >= 0x200 && offset < 0x240) {
109         return s->vect_control[(offset - 0x200) >> 2];
110     }
111     switch (offset >> 2) {
112     case 0: /* IRQSTATUS */
113         return pl190_irq_level(s);
114     case 1: /* FIQSATUS */
115         return (s->level | s->soft_level) & s->fiq_select;
116     case 2: /* RAWINTR */
117         return s->level | s->soft_level;
118     case 3: /* INTSELECT */
119         return s->fiq_select;
120     case 4: /* INTENABLE */
121         return s->irq_enable;
122     case 6: /* SOFTINT */
123         return s->soft_level;
124     case 8: /* PROTECTION */
125         return s->protected;
126     case 12: /* VECTADDR */
127         /* Read vector address at the start of an ISR.  Increases the
128          * current priority level to that of the current interrupt.
129          *
130          * Since an enabled interrupt X at priority P causes prio_mask[Y]
131          * to have bit X set for all Y > P, this loop will stop with
132          * i == the priority of the highest priority set interrupt.
133          */
134         for (i = 0; i < s->priority; i++) {
135             if ((s->level | s->soft_level) & s->prio_mask[i + 1]) {
136                 break;
137             }
138         }
139 
140         /* Reading this value with no pending interrupts is undefined.
141            We return the default address.  */
142         if (i == PL190_NUM_PRIO)
143           return s->vect_addr[16];
144         if (i < s->priority)
145           {
146             s->prev_prio[i] = s->priority;
147             s->priority = i;
148             pl190_update(s);
149           }
150         return s->vect_addr[s->priority];
151     case 13: /* DEFVECTADDR */
152         return s->vect_addr[16];
153     default:
154         qemu_log_mask(LOG_GUEST_ERROR,
155                       "pl190_read: Bad offset %x\n", (int)offset);
156         return 0;
157     }
158 }
159 
160 static void pl190_write(void *opaque, hwaddr offset,
161                         uint64_t val, unsigned size)
162 {
163     PL190State *s = (PL190State *)opaque;
164 
165     if (offset >= 0x100 && offset < 0x140) {
166         s->vect_addr[(offset - 0x100) >> 2] = val;
167         pl190_update_vectors(s);
168         return;
169     }
170     if (offset >= 0x200 && offset < 0x240) {
171         s->vect_control[(offset - 0x200) >> 2] = val;
172         pl190_update_vectors(s);
173         return;
174     }
175     switch (offset >> 2) {
176     case 0: /* SELECT */
177         /* This is a readonly register, but linux tries to write to it
178            anyway.  Ignore the write.  */
179         break;
180     case 3: /* INTSELECT */
181         s->fiq_select = val;
182         break;
183     case 4: /* INTENABLE */
184         s->irq_enable |= val;
185         break;
186     case 5: /* INTENCLEAR */
187         s->irq_enable &= ~val;
188         break;
189     case 6: /* SOFTINT */
190         s->soft_level |= val;
191         break;
192     case 7: /* SOFTINTCLEAR */
193         s->soft_level &= ~val;
194         break;
195     case 8: /* PROTECTION */
196         /* TODO: Protection (supervisor only access) is not implemented.  */
197         s->protected = val & 1;
198         break;
199     case 12: /* VECTADDR */
200         /* Restore the previous priority level.  The value written is
201            ignored.  */
202         if (s->priority < PL190_NUM_PRIO)
203             s->priority = s->prev_prio[s->priority];
204         break;
205     case 13: /* DEFVECTADDR */
206         s->vect_addr[16] = val;
207         break;
208     case 0xc0: /* ITCR */
209         if (val) {
210             qemu_log_mask(LOG_UNIMP, "pl190: Test mode not implemented\n");
211         }
212         break;
213     default:
214         qemu_log_mask(LOG_GUEST_ERROR,
215                      "pl190_write: Bad offset %x\n", (int)offset);
216         return;
217     }
218     pl190_update(s);
219 }
220 
221 static const MemoryRegionOps pl190_ops = {
222     .read = pl190_read,
223     .write = pl190_write,
224     .endianness = DEVICE_NATIVE_ENDIAN,
225 };
226 
227 static void pl190_reset(DeviceState *d)
228 {
229     PL190State *s = PL190(d);
230     int i;
231 
232     for (i = 0; i < 16; i++) {
233         s->vect_addr[i] = 0;
234         s->vect_control[i] = 0;
235     }
236     s->vect_addr[16] = 0;
237     s->prio_mask[17] = 0xffffffff;
238     s->priority = PL190_NUM_PRIO;
239     pl190_update_vectors(s);
240 }
241 
242 static void pl190_init(Object *obj)
243 {
244     DeviceState *dev = DEVICE(obj);
245     PL190State *s = PL190(obj);
246     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
247 
248     memory_region_init_io(&s->iomem, obj, &pl190_ops, s, "pl190", 0x1000);
249     sysbus_init_mmio(sbd, &s->iomem);
250     qdev_init_gpio_in(dev, pl190_set_irq, 32);
251     sysbus_init_irq(sbd, &s->irq);
252     sysbus_init_irq(sbd, &s->fiq);
253 }
254 
255 static const VMStateDescription vmstate_pl190 = {
256     .name = "pl190",
257     .version_id = 1,
258     .minimum_version_id = 1,
259     .fields = (VMStateField[]) {
260         VMSTATE_UINT32(level, PL190State),
261         VMSTATE_UINT32(soft_level, PL190State),
262         VMSTATE_UINT32(irq_enable, PL190State),
263         VMSTATE_UINT32(fiq_select, PL190State),
264         VMSTATE_UINT8_ARRAY(vect_control, PL190State, 16),
265         VMSTATE_UINT32_ARRAY(vect_addr, PL190State, PL190_NUM_PRIO),
266         VMSTATE_UINT32_ARRAY(prio_mask, PL190State, PL190_NUM_PRIO+1),
267         VMSTATE_INT32(protected, PL190State),
268         VMSTATE_INT32(priority, PL190State),
269         VMSTATE_INT32_ARRAY(prev_prio, PL190State, PL190_NUM_PRIO),
270         VMSTATE_END_OF_LIST()
271     }
272 };
273 
274 static void pl190_class_init(ObjectClass *klass, void *data)
275 {
276     DeviceClass *dc = DEVICE_CLASS(klass);
277 
278     dc->reset = pl190_reset;
279     dc->vmsd = &vmstate_pl190;
280 }
281 
282 static const TypeInfo pl190_info = {
283     .name          = TYPE_PL190,
284     .parent        = TYPE_SYS_BUS_DEVICE,
285     .instance_size = sizeof(PL190State),
286     .instance_init = pl190_init,
287     .class_init    = pl190_class_init,
288 };
289 
290 static void pl190_register_types(void)
291 {
292     type_register_static(&pl190_info);
293 }
294 
295 type_init(pl190_register_types)
296