xref: /openbmc/qemu/hw/intc/pl190.c (revision 37677d7d)
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/sysbus.h"
12 #include "qemu/log.h"
13 #include "qemu/module.h"
14 
15 /* The number of virtual priority levels.  16 user vectors plus the
16    unvectored IRQ.  Chained interrupts would require an additional level
17    if implemented.  */
18 
19 #define PL190_NUM_PRIO 17
20 
21 #define TYPE_PL190 "pl190"
22 #define PL190(obj) OBJECT_CHECK(PL190State, (obj), TYPE_PL190)
23 
24 typedef struct PL190State {
25     SysBusDevice parent_obj;
26 
27     MemoryRegion iomem;
28     uint32_t level;
29     uint32_t soft_level;
30     uint32_t irq_enable;
31     uint32_t fiq_select;
32     uint8_t vect_control[16];
33     uint32_t vect_addr[PL190_NUM_PRIO];
34     /* Mask containing interrupts with higher priority than this one.  */
35     uint32_t prio_mask[PL190_NUM_PRIO + 1];
36     int protected;
37     /* Current priority level.  */
38     int priority;
39     int prev_prio[PL190_NUM_PRIO];
40     qemu_irq irq;
41     qemu_irq fiq;
42 } PL190State;
43 
44 static const unsigned char pl190_id[] =
45 { 0x90, 0x11, 0x04, 0x00, 0x0D, 0xf0, 0x05, 0xb1 };
46 
47 static inline uint32_t pl190_irq_level(PL190State *s)
48 {
49     return (s->level | s->soft_level) & s->irq_enable & ~s->fiq_select;
50 }
51 
52 /* Update interrupts.  */
53 static void pl190_update(PL190State *s)
54 {
55     uint32_t level = pl190_irq_level(s);
56     int set;
57 
58     set = (level & s->prio_mask[s->priority]) != 0;
59     qemu_set_irq(s->irq, set);
60     set = ((s->level | s->soft_level) & s->fiq_select) != 0;
61     qemu_set_irq(s->fiq, set);
62 }
63 
64 static void pl190_set_irq(void *opaque, int irq, int level)
65 {
66     PL190State *s = (PL190State *)opaque;
67 
68     if (level)
69         s->level |= 1u << irq;
70     else
71         s->level &= ~(1u << irq);
72     pl190_update(s);
73 }
74 
75 static void pl190_update_vectors(PL190State *s)
76 {
77     uint32_t mask;
78     int i;
79     int n;
80 
81     mask = 0;
82     for (i = 0; i < 16; i++)
83       {
84         s->prio_mask[i] = mask;
85         if (s->vect_control[i] & 0x20)
86           {
87             n = s->vect_control[i] & 0x1f;
88             mask |= 1 << n;
89           }
90       }
91     s->prio_mask[16] = mask;
92     pl190_update(s);
93 }
94 
95 static uint64_t pl190_read(void *opaque, hwaddr offset,
96                            unsigned size)
97 {
98     PL190State *s = (PL190State *)opaque;
99     int i;
100 
101     if (offset >= 0xfe0 && offset < 0x1000) {
102         return pl190_id[(offset - 0xfe0) >> 2];
103     }
104     if (offset >= 0x100 && offset < 0x140) {
105         return s->vect_addr[(offset - 0x100) >> 2];
106     }
107     if (offset >= 0x200 && offset < 0x240) {
108         return s->vect_control[(offset - 0x200) >> 2];
109     }
110     switch (offset >> 2) {
111     case 0: /* IRQSTATUS */
112         return pl190_irq_level(s);
113     case 1: /* FIQSATUS */
114         return (s->level | s->soft_level) & s->fiq_select;
115     case 2: /* RAWINTR */
116         return s->level | s->soft_level;
117     case 3: /* INTSELECT */
118         return s->fiq_select;
119     case 4: /* INTENABLE */
120         return s->irq_enable;
121     case 6: /* SOFTINT */
122         return s->soft_level;
123     case 8: /* PROTECTION */
124         return s->protected;
125     case 12: /* VECTADDR */
126         /* Read vector address at the start of an ISR.  Increases the
127          * current priority level to that of the current interrupt.
128          *
129          * Since an enabled interrupt X at priority P causes prio_mask[Y]
130          * to have bit X set for all Y > P, this loop will stop with
131          * i == the priority of the highest priority set interrupt.
132          */
133         for (i = 0; i < s->priority; i++) {
134             if ((s->level | s->soft_level) & s->prio_mask[i + 1]) {
135                 break;
136             }
137         }
138 
139         /* Reading this value with no pending interrupts is undefined.
140            We return the default address.  */
141         if (i == PL190_NUM_PRIO)
142           return s->vect_addr[16];
143         if (i < s->priority)
144           {
145             s->prev_prio[i] = s->priority;
146             s->priority = i;
147             pl190_update(s);
148           }
149         return s->vect_addr[s->priority];
150     case 13: /* DEFVECTADDR */
151         return s->vect_addr[16];
152     default:
153         qemu_log_mask(LOG_GUEST_ERROR,
154                       "pl190_read: Bad offset %x\n", (int)offset);
155         return 0;
156     }
157 }
158 
159 static void pl190_write(void *opaque, hwaddr offset,
160                         uint64_t val, unsigned size)
161 {
162     PL190State *s = (PL190State *)opaque;
163 
164     if (offset >= 0x100 && offset < 0x140) {
165         s->vect_addr[(offset - 0x100) >> 2] = val;
166         pl190_update_vectors(s);
167         return;
168     }
169     if (offset >= 0x200 && offset < 0x240) {
170         s->vect_control[(offset - 0x200) >> 2] = val;
171         pl190_update_vectors(s);
172         return;
173     }
174     switch (offset >> 2) {
175     case 0: /* SELECT */
176         /* This is a readonly register, but linux tries to write to it
177            anyway.  Ignore the write.  */
178         break;
179     case 3: /* INTSELECT */
180         s->fiq_select = val;
181         break;
182     case 4: /* INTENABLE */
183         s->irq_enable |= val;
184         break;
185     case 5: /* INTENCLEAR */
186         s->irq_enable &= ~val;
187         break;
188     case 6: /* SOFTINT */
189         s->soft_level |= val;
190         break;
191     case 7: /* SOFTINTCLEAR */
192         s->soft_level &= ~val;
193         break;
194     case 8: /* PROTECTION */
195         /* TODO: Protection (supervisor only access) is not implemented.  */
196         s->protected = val & 1;
197         break;
198     case 12: /* VECTADDR */
199         /* Restore the previous priority level.  The value written is
200            ignored.  */
201         if (s->priority < PL190_NUM_PRIO)
202             s->priority = s->prev_prio[s->priority];
203         break;
204     case 13: /* DEFVECTADDR */
205         s->vect_addr[16] = val;
206         break;
207     case 0xc0: /* ITCR */
208         if (val) {
209             qemu_log_mask(LOG_UNIMP, "pl190: Test mode not implemented\n");
210         }
211         break;
212     default:
213         qemu_log_mask(LOG_GUEST_ERROR,
214                      "pl190_write: Bad offset %x\n", (int)offset);
215         return;
216     }
217     pl190_update(s);
218 }
219 
220 static const MemoryRegionOps pl190_ops = {
221     .read = pl190_read,
222     .write = pl190_write,
223     .endianness = DEVICE_NATIVE_ENDIAN,
224 };
225 
226 static void pl190_reset(DeviceState *d)
227 {
228     PL190State *s = PL190(d);
229     int i;
230 
231     for (i = 0; i < 16; i++) {
232         s->vect_addr[i] = 0;
233         s->vect_control[i] = 0;
234     }
235     s->vect_addr[16] = 0;
236     s->prio_mask[17] = 0xffffffff;
237     s->priority = PL190_NUM_PRIO;
238     pl190_update_vectors(s);
239 }
240 
241 static void pl190_init(Object *obj)
242 {
243     DeviceState *dev = DEVICE(obj);
244     PL190State *s = PL190(obj);
245     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
246 
247     memory_region_init_io(&s->iomem, obj, &pl190_ops, s, "pl190", 0x1000);
248     sysbus_init_mmio(sbd, &s->iomem);
249     qdev_init_gpio_in(dev, pl190_set_irq, 32);
250     sysbus_init_irq(sbd, &s->irq);
251     sysbus_init_irq(sbd, &s->fiq);
252 }
253 
254 static const VMStateDescription vmstate_pl190 = {
255     .name = "pl190",
256     .version_id = 1,
257     .minimum_version_id = 1,
258     .fields = (VMStateField[]) {
259         VMSTATE_UINT32(level, PL190State),
260         VMSTATE_UINT32(soft_level, PL190State),
261         VMSTATE_UINT32(irq_enable, PL190State),
262         VMSTATE_UINT32(fiq_select, PL190State),
263         VMSTATE_UINT8_ARRAY(vect_control, PL190State, 16),
264         VMSTATE_UINT32_ARRAY(vect_addr, PL190State, PL190_NUM_PRIO),
265         VMSTATE_UINT32_ARRAY(prio_mask, PL190State, PL190_NUM_PRIO+1),
266         VMSTATE_INT32(protected, PL190State),
267         VMSTATE_INT32(priority, PL190State),
268         VMSTATE_INT32_ARRAY(prev_prio, PL190State, PL190_NUM_PRIO),
269         VMSTATE_END_OF_LIST()
270     }
271 };
272 
273 static void pl190_class_init(ObjectClass *klass, void *data)
274 {
275     DeviceClass *dc = DEVICE_CLASS(klass);
276 
277     dc->reset = pl190_reset;
278     dc->vmsd = &vmstate_pl190;
279 }
280 
281 static const TypeInfo pl190_info = {
282     .name          = TYPE_PL190,
283     .parent        = TYPE_SYS_BUS_DEVICE,
284     .instance_size = sizeof(PL190State),
285     .instance_init = pl190_init,
286     .class_init    = pl190_class_init,
287 };
288 
289 static void pl190_register_types(void)
290 {
291     type_register_static(&pl190_info);
292 }
293 
294 type_init(pl190_register_types)
295