xref: /openbmc/qemu/hw/intc/imx_avic.c (revision 2e1cacfb)
1 /*
2  * i.MX31 Vectored Interrupt Controller
3  *
4  * Note this is NOT the PL192 provided by ARM, but
5  * a custom implementation by Freescale.
6  *
7  * Copyright (c) 2008 OKL
8  * Copyright (c) 2011 NICTA Pty Ltd
9  * Originally written by Hans Jiang
10  * Updated by Jean-Christophe Dubois <jcd@tribudubois.net>
11  *
12  * This code is licensed under the GPL version 2 or later.  See
13  * the COPYING file in the top-level directory.
14  *
15  * TODO: implement vectors.
16  */
17 
18 #include "qemu/osdep.h"
19 #include "hw/intc/imx_avic.h"
20 #include "hw/irq.h"
21 #include "migration/vmstate.h"
22 #include "qemu/log.h"
23 #include "qemu/module.h"
24 
25 #ifndef DEBUG_IMX_AVIC
26 #define DEBUG_IMX_AVIC 0
27 #endif
28 
29 #define DPRINTF(fmt, args...) \
30     do { \
31         if (DEBUG_IMX_AVIC) { \
32             fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_AVIC, \
33                                              __func__, ##args); \
34         } \
35     } while (0)
36 
37 static const VMStateDescription vmstate_imx_avic = {
38     .name = TYPE_IMX_AVIC,
39     .version_id = 1,
40     .minimum_version_id = 1,
41     .fields = (const VMStateField[]) {
42         VMSTATE_UINT64(pending, IMXAVICState),
43         VMSTATE_UINT64(enabled, IMXAVICState),
44         VMSTATE_UINT64(is_fiq, IMXAVICState),
45         VMSTATE_UINT32(intcntl, IMXAVICState),
46         VMSTATE_UINT32(intmask, IMXAVICState),
47         VMSTATE_UINT32_ARRAY(prio, IMXAVICState, PRIO_WORDS),
48         VMSTATE_END_OF_LIST()
49     },
50 };
51 
52 static inline int imx_avic_prio(IMXAVICState *s, int irq)
53 {
54     uint32_t word = irq / PRIO_PER_WORD;
55     uint32_t part = 4 * (irq % PRIO_PER_WORD);
56     return 0xf & (s->prio[word] >> part);
57 }
58 
59 /* Update interrupts.  */
60 static void imx_avic_update(IMXAVICState *s)
61 {
62     int i;
63     uint64_t new = s->pending & s->enabled;
64     uint64_t flags;
65 
66     flags = new & s->is_fiq;
67     qemu_set_irq(s->fiq, !!flags);
68 
69     flags = new & ~s->is_fiq;
70     if (!flags || (s->intmask == 0x1f)) {
71         qemu_set_irq(s->irq, !!flags);
72         return;
73     }
74 
75     /*
76      * Take interrupt if there's a pending interrupt with
77      * priority higher than the value of intmask
78      */
79     for (i = 0; i < IMX_AVIC_NUM_IRQS; i++) {
80         if (flags & (1UL << i)) {
81             if (imx_avic_prio(s, i) > s->intmask) {
82                 qemu_set_irq(s->irq, 1);
83                 return;
84             }
85         }
86     }
87     qemu_set_irq(s->irq, 0);
88 }
89 
90 static void imx_avic_set_irq(void *opaque, int irq, int level)
91 {
92     IMXAVICState *s = (IMXAVICState *)opaque;
93 
94     if (level) {
95         DPRINTF("Raising IRQ %d, prio %d\n",
96                 irq, imx_avic_prio(s, irq));
97         s->pending |= (1ULL << irq);
98     } else {
99         DPRINTF("Clearing IRQ %d, prio %d\n",
100                 irq, imx_avic_prio(s, irq));
101         s->pending &= ~(1ULL << irq);
102     }
103 
104     imx_avic_update(s);
105 }
106 
107 
108 static uint64_t imx_avic_read(void *opaque,
109                              hwaddr offset, unsigned size)
110 {
111     IMXAVICState *s = (IMXAVICState *)opaque;
112 
113     DPRINTF("read(offset = 0x%" HWADDR_PRIx ")\n", offset);
114 
115     switch (offset >> 2) {
116     case 0: /* INTCNTL */
117         return s->intcntl;
118 
119     case 1: /* Normal Interrupt Mask Register, NIMASK */
120         return s->intmask;
121 
122     case 2: /* Interrupt Enable Number Register, INTENNUM */
123     case 3: /* Interrupt Disable Number Register, INTDISNUM */
124         return 0;
125 
126     case 4: /* Interrupt Enabled Number Register High */
127         return s->enabled >> 32;
128 
129     case 5: /* Interrupt Enabled Number Register Low */
130         return s->enabled & 0xffffffffULL;
131 
132     case 6: /* Interrupt Type Register High */
133         return s->is_fiq >> 32;
134 
135     case 7: /* Interrupt Type Register Low */
136         return s->is_fiq & 0xffffffffULL;
137 
138     case 8: /* Normal Interrupt Priority Register 7 */
139     case 9: /* Normal Interrupt Priority Register 6 */
140     case 10:/* Normal Interrupt Priority Register 5 */
141     case 11:/* Normal Interrupt Priority Register 4 */
142     case 12:/* Normal Interrupt Priority Register 3 */
143     case 13:/* Normal Interrupt Priority Register 2 */
144     case 14:/* Normal Interrupt Priority Register 1 */
145     case 15:/* Normal Interrupt Priority Register 0 */
146         return s->prio[15-(offset>>2)];
147 
148     case 16: /* Normal interrupt vector and status register */
149     {
150         /*
151          * This returns the highest priority
152          * outstanding interrupt.  Where there is more than
153          * one pending IRQ with the same priority,
154          * take the highest numbered one.
155          */
156         uint64_t flags = s->pending & s->enabled & ~s->is_fiq;
157         int i;
158         int prio = -1;
159         int irq = -1;
160         for (i = 63; i >= 0; --i) {
161             if (flags & (1ULL<<i)) {
162                 int irq_prio = imx_avic_prio(s, i);
163                 if (irq_prio > prio) {
164                     irq = i;
165                     prio = irq_prio;
166                 }
167             }
168         }
169         if (irq >= 0) {
170             imx_avic_set_irq(s, irq, 0);
171             return irq << 16 | prio;
172         }
173         return 0xffffffffULL;
174     }
175     case 17:/* Fast Interrupt vector and status register */
176     {
177         uint64_t flags = s->pending & s->enabled & s->is_fiq;
178         int i = ctz64(flags);
179         if (i < 64) {
180             imx_avic_set_irq(opaque, i, 0);
181             return i;
182         }
183         return 0xffffffffULL;
184     }
185     case 18:/* Interrupt source register high */
186         return s->pending >> 32;
187 
188     case 19:/* Interrupt source register low */
189         return s->pending & 0xffffffffULL;
190 
191     case 20:/* Interrupt Force Register high */
192     case 21:/* Interrupt Force Register low */
193         return 0;
194 
195     case 22:/* Normal Interrupt Pending Register High */
196         return (s->pending & s->enabled & ~s->is_fiq) >> 32;
197 
198     case 23:/* Normal Interrupt Pending Register Low */
199         return (s->pending & s->enabled & ~s->is_fiq) & 0xffffffffULL;
200 
201     case 24: /* Fast Interrupt Pending Register High  */
202         return (s->pending & s->enabled & s->is_fiq) >> 32;
203 
204     case 25: /* Fast Interrupt Pending Register Low  */
205         return (s->pending & s->enabled & s->is_fiq) & 0xffffffffULL;
206 
207     case 0x40:            /* AVIC vector 0, use for WFI WAR */
208         return 0x4;
209 
210     default:
211         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
212                       HWADDR_PRIx "\n", TYPE_IMX_AVIC, __func__, offset);
213         return 0;
214     }
215 }
216 
217 static void imx_avic_write(void *opaque, hwaddr offset,
218                           uint64_t val, unsigned size)
219 {
220     IMXAVICState *s = (IMXAVICState *)opaque;
221 
222     /* Vector Registers not yet supported */
223     if (offset >= 0x100 && offset <= 0x2fc) {
224         qemu_log_mask(LOG_UNIMP, "[%s]%s: vector %d ignored\n",
225                       TYPE_IMX_AVIC, __func__, (int)((offset - 0x100) >> 2));
226         return;
227     }
228 
229     DPRINTF("(0x%" HWADDR_PRIx ") = 0x%x\n", offset, (unsigned int)val);
230 
231     switch (offset >> 2) {
232     case 0: /* Interrupt Control Register, INTCNTL */
233         s->intcntl = val & (ABFEN | NIDIS | FIDIS | NIAD | FIAD | NM);
234         if (s->intcntl & ABFEN) {
235             s->intcntl &= ~(val & ABFLAG);
236         }
237         break;
238 
239     case 1: /* Normal Interrupt Mask Register, NIMASK */
240         s->intmask = val & 0x1f;
241         break;
242 
243     case 2: /* Interrupt Enable Number Register, INTENNUM */
244         DPRINTF("enable(%d)\n", (int)val);
245         val &= 0x3f;
246         s->enabled |= (1ULL << val);
247         break;
248 
249     case 3: /* Interrupt Disable Number Register, INTDISNUM */
250         DPRINTF("disable(%d)\n", (int)val);
251         val &= 0x3f;
252         s->enabled &= ~(1ULL << val);
253         break;
254 
255     case 4: /* Interrupt Enable Number Register High */
256         s->enabled = (s->enabled & 0xffffffffULL) | (val << 32);
257         break;
258 
259     case 5: /* Interrupt Enable Number Register Low */
260         s->enabled = (s->enabled & 0xffffffff00000000ULL) | val;
261         break;
262 
263     case 6: /* Interrupt Type Register High */
264         s->is_fiq = (s->is_fiq & 0xffffffffULL) | (val << 32);
265         break;
266 
267     case 7: /* Interrupt Type Register Low */
268         s->is_fiq = (s->is_fiq & 0xffffffff00000000ULL) | val;
269         break;
270 
271     case 8: /* Normal Interrupt Priority Register 7 */
272     case 9: /* Normal Interrupt Priority Register 6 */
273     case 10:/* Normal Interrupt Priority Register 5 */
274     case 11:/* Normal Interrupt Priority Register 4 */
275     case 12:/* Normal Interrupt Priority Register 3 */
276     case 13:/* Normal Interrupt Priority Register 2 */
277     case 14:/* Normal Interrupt Priority Register 1 */
278     case 15:/* Normal Interrupt Priority Register 0 */
279         s->prio[15-(offset>>2)] = val;
280         break;
281 
282         /* Read-only registers, writes ignored */
283     case 16:/* Normal Interrupt Vector and Status register */
284     case 17:/* Fast Interrupt vector and status register */
285     case 18:/* Interrupt source register high */
286     case 19:/* Interrupt source register low */
287         return;
288 
289     case 20:/* Interrupt Force Register high */
290         s->pending = (s->pending & 0xffffffffULL) | (val << 32);
291         break;
292 
293     case 21:/* Interrupt Force Register low */
294         s->pending = (s->pending & 0xffffffff00000000ULL) | val;
295         break;
296 
297     case 22:/* Normal Interrupt Pending Register High */
298     case 23:/* Normal Interrupt Pending Register Low */
299     case 24: /* Fast Interrupt Pending Register High  */
300     case 25: /* Fast Interrupt Pending Register Low  */
301         return;
302 
303     default:
304         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
305                       HWADDR_PRIx "\n", TYPE_IMX_AVIC, __func__, offset);
306     }
307     imx_avic_update(s);
308 }
309 
310 static const MemoryRegionOps imx_avic_ops = {
311     .read = imx_avic_read,
312     .write = imx_avic_write,
313     .endianness = DEVICE_NATIVE_ENDIAN,
314 };
315 
316 static void imx_avic_reset(DeviceState *dev)
317 {
318     IMXAVICState *s = IMX_AVIC(dev);
319 
320     s->pending = 0;
321     s->enabled = 0;
322     s->is_fiq = 0;
323     s->intmask = 0x1f;
324     s->intcntl = 0;
325     memset(s->prio, 0, sizeof s->prio);
326 }
327 
328 static void imx_avic_init(Object *obj)
329 {
330     DeviceState *dev = DEVICE(obj);
331     IMXAVICState *s = IMX_AVIC(obj);
332     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
333 
334     memory_region_init_io(&s->iomem, obj, &imx_avic_ops, s,
335                           TYPE_IMX_AVIC, 0x1000);
336     sysbus_init_mmio(sbd, &s->iomem);
337 
338     qdev_init_gpio_in(dev, imx_avic_set_irq, IMX_AVIC_NUM_IRQS);
339     sysbus_init_irq(sbd, &s->irq);
340     sysbus_init_irq(sbd, &s->fiq);
341 }
342 
343 
344 static void imx_avic_class_init(ObjectClass *klass, void *data)
345 {
346     DeviceClass *dc = DEVICE_CLASS(klass);
347 
348     dc->vmsd = &vmstate_imx_avic;
349     device_class_set_legacy_reset(dc, imx_avic_reset);
350     dc->desc = "i.MX Advanced Vector Interrupt Controller";
351 }
352 
353 static const TypeInfo imx_avic_info = {
354     .name = TYPE_IMX_AVIC,
355     .parent = TYPE_SYS_BUS_DEVICE,
356     .instance_size = sizeof(IMXAVICState),
357     .instance_init = imx_avic_init,
358     .class_init = imx_avic_class_init,
359 };
360 
361 static void imx_avic_register_types(void)
362 {
363     type_register_static(&imx_avic_info);
364 }
365 
366 type_init(imx_avic_register_types)
367