xref: /openbmc/qemu/hw/intc/imx_avic.c (revision 40d6ee94)
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 "qemu/log.h"
21 
22 #ifndef DEBUG_IMX_AVIC
23 #define DEBUG_IMX_AVIC 0
24 #endif
25 
26 #define DPRINTF(fmt, args...) \
27     do { \
28         if (DEBUG_IMX_AVIC) { \
29             fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_AVIC, \
30                                              __func__, ##args); \
31         } \
32     } while (0)
33 
34 static const VMStateDescription vmstate_imx_avic = {
35     .name = TYPE_IMX_AVIC,
36     .version_id = 1,
37     .minimum_version_id = 1,
38     .fields = (VMStateField[]) {
39         VMSTATE_UINT64(pending, IMXAVICState),
40         VMSTATE_UINT64(enabled, IMXAVICState),
41         VMSTATE_UINT64(is_fiq, IMXAVICState),
42         VMSTATE_UINT32(intcntl, IMXAVICState),
43         VMSTATE_UINT32(intmask, IMXAVICState),
44         VMSTATE_UINT32_ARRAY(prio, IMXAVICState, PRIO_WORDS),
45         VMSTATE_END_OF_LIST()
46     },
47 };
48 
49 static inline int imx_avic_prio(IMXAVICState *s, int irq)
50 {
51     uint32_t word = irq / PRIO_PER_WORD;
52     uint32_t part = 4 * (irq % PRIO_PER_WORD);
53     return 0xf & (s->prio[word] >> part);
54 }
55 
56 /* Update interrupts.  */
57 static void imx_avic_update(IMXAVICState *s)
58 {
59     int i;
60     uint64_t new = s->pending & s->enabled;
61     uint64_t flags;
62 
63     flags = new & s->is_fiq;
64     qemu_set_irq(s->fiq, !!flags);
65 
66     flags = new & ~s->is_fiq;
67     if (!flags || (s->intmask == 0x1f)) {
68         qemu_set_irq(s->irq, !!flags);
69         return;
70     }
71 
72     /*
73      * Take interrupt if there's a pending interrupt with
74      * priority higher than the value of intmask
75      */
76     for (i = 0; i < IMX_AVIC_NUM_IRQS; i++) {
77         if (flags & (1UL << i)) {
78             if (imx_avic_prio(s, i) > s->intmask) {
79                 qemu_set_irq(s->irq, 1);
80                 return;
81             }
82         }
83     }
84     qemu_set_irq(s->irq, 0);
85 }
86 
87 static void imx_avic_set_irq(void *opaque, int irq, int level)
88 {
89     IMXAVICState *s = (IMXAVICState *)opaque;
90 
91     if (level) {
92         DPRINTF("Raising IRQ %d, prio %d\n",
93                 irq, imx_avic_prio(s, irq));
94         s->pending |= (1ULL << irq);
95     } else {
96         DPRINTF("Clearing IRQ %d, prio %d\n",
97                 irq, imx_avic_prio(s, irq));
98         s->pending &= ~(1ULL << irq);
99     }
100 
101     imx_avic_update(s);
102 }
103 
104 
105 static uint64_t imx_avic_read(void *opaque,
106                              hwaddr offset, unsigned size)
107 {
108     IMXAVICState *s = (IMXAVICState *)opaque;
109 
110     DPRINTF("read(offset = 0x%" HWADDR_PRIx ")\n", offset);
111 
112     switch (offset >> 2) {
113     case 0: /* INTCNTL */
114         return s->intcntl;
115 
116     case 1: /* Normal Interrupt Mask Register, NIMASK */
117         return s->intmask;
118 
119     case 2: /* Interrupt Enable Number Register, INTENNUM */
120     case 3: /* Interrupt Disable Number Register, INTDISNUM */
121         return 0;
122 
123     case 4: /* Interrupt Enabled Number Register High */
124         return s->enabled >> 32;
125 
126     case 5: /* Interrupt Enabled Number Register Low */
127         return s->enabled & 0xffffffffULL;
128 
129     case 6: /* Interrupt Type Register High */
130         return s->is_fiq >> 32;
131 
132     case 7: /* Interrupt Type Register Low */
133         return s->is_fiq & 0xffffffffULL;
134 
135     case 8: /* Normal Interrupt Priority Register 7 */
136     case 9: /* Normal Interrupt Priority Register 6 */
137     case 10:/* Normal Interrupt Priority Register 5 */
138     case 11:/* Normal Interrupt Priority Register 4 */
139     case 12:/* Normal Interrupt Priority Register 3 */
140     case 13:/* Normal Interrupt Priority Register 2 */
141     case 14:/* Normal Interrupt Priority Register 1 */
142     case 15:/* Normal Interrupt Priority Register 0 */
143         return s->prio[15-(offset>>2)];
144 
145     case 16: /* Normal interrupt vector and status register */
146     {
147         /*
148          * This returns the highest priority
149          * outstanding interrupt.  Where there is more than
150          * one pending IRQ with the same priority,
151          * take the highest numbered one.
152          */
153         uint64_t flags = s->pending & s->enabled & ~s->is_fiq;
154         int i;
155         int prio = -1;
156         int irq = -1;
157         for (i = 63; i >= 0; --i) {
158             if (flags & (1ULL<<i)) {
159                 int irq_prio = imx_avic_prio(s, i);
160                 if (irq_prio > prio) {
161                     irq = i;
162                     prio = irq_prio;
163                 }
164             }
165         }
166         if (irq >= 0) {
167             imx_avic_set_irq(s, irq, 0);
168             return irq << 16 | prio;
169         }
170         return 0xffffffffULL;
171     }
172     case 17:/* Fast Interrupt vector and status register */
173     {
174         uint64_t flags = s->pending & s->enabled & s->is_fiq;
175         int i = ctz64(flags);
176         if (i < 64) {
177             imx_avic_set_irq(opaque, i, 0);
178             return i;
179         }
180         return 0xffffffffULL;
181     }
182     case 18:/* Interrupt source register high */
183         return s->pending >> 32;
184 
185     case 19:/* Interrupt source register low */
186         return s->pending & 0xffffffffULL;
187 
188     case 20:/* Interrupt Force Register high */
189     case 21:/* Interrupt Force Register low */
190         return 0;
191 
192     case 22:/* Normal Interrupt Pending Register High */
193         return (s->pending & s->enabled & ~s->is_fiq) >> 32;
194 
195     case 23:/* Normal Interrupt Pending Register Low */
196         return (s->pending & s->enabled & ~s->is_fiq) & 0xffffffffULL;
197 
198     case 24: /* Fast Interrupt Pending Register High  */
199         return (s->pending & s->enabled & s->is_fiq) >> 32;
200 
201     case 25: /* Fast Interrupt Pending Register Low  */
202         return (s->pending & s->enabled & s->is_fiq) & 0xffffffffULL;
203 
204     case 0x40:            /* AVIC vector 0, use for WFI WAR */
205         return 0x4;
206 
207     default:
208         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
209                       HWADDR_PRIx "\n", TYPE_IMX_AVIC, __func__, offset);
210         return 0;
211     }
212 }
213 
214 static void imx_avic_write(void *opaque, hwaddr offset,
215                           uint64_t val, unsigned size)
216 {
217     IMXAVICState *s = (IMXAVICState *)opaque;
218 
219     /* Vector Registers not yet supported */
220     if (offset >= 0x100 && offset <= 0x2fc) {
221         qemu_log_mask(LOG_UNIMP, "[%s]%s: vector %d ignored\n",
222                       TYPE_IMX_AVIC, __func__, (int)((offset - 0x100) >> 2));
223         return;
224     }
225 
226     DPRINTF("(0x%" HWADDR_PRIx ") = 0x%x\n", offset, (unsigned int)val);
227 
228     switch (offset >> 2) {
229     case 0: /* Interrupt Control Register, INTCNTL */
230         s->intcntl = val & (ABFEN | NIDIS | FIDIS | NIAD | FIAD | NM);
231         if (s->intcntl & ABFEN) {
232             s->intcntl &= ~(val & ABFLAG);
233         }
234         break;
235 
236     case 1: /* Normal Interrupt Mask Register, NIMASK */
237         s->intmask = val & 0x1f;
238         break;
239 
240     case 2: /* Interrupt Enable Number Register, INTENNUM */
241         DPRINTF("enable(%d)\n", (int)val);
242         val &= 0x3f;
243         s->enabled |= (1ULL << val);
244         break;
245 
246     case 3: /* Interrupt Disable Number Register, INTDISNUM */
247         DPRINTF("disable(%d)\n", (int)val);
248         val &= 0x3f;
249         s->enabled &= ~(1ULL << val);
250         break;
251 
252     case 4: /* Interrupt Enable Number Register High */
253         s->enabled = (s->enabled & 0xffffffffULL) | (val << 32);
254         break;
255 
256     case 5: /* Interrupt Enable Number Register Low */
257         s->enabled = (s->enabled & 0xffffffff00000000ULL) | val;
258         break;
259 
260     case 6: /* Interrupt Type Register High */
261         s->is_fiq = (s->is_fiq & 0xffffffffULL) | (val << 32);
262         break;
263 
264     case 7: /* Interrupt Type Register Low */
265         s->is_fiq = (s->is_fiq & 0xffffffff00000000ULL) | val;
266         break;
267 
268     case 8: /* Normal Interrupt Priority Register 7 */
269     case 9: /* Normal Interrupt Priority Register 6 */
270     case 10:/* Normal Interrupt Priority Register 5 */
271     case 11:/* Normal Interrupt Priority Register 4 */
272     case 12:/* Normal Interrupt Priority Register 3 */
273     case 13:/* Normal Interrupt Priority Register 2 */
274     case 14:/* Normal Interrupt Priority Register 1 */
275     case 15:/* Normal Interrupt Priority Register 0 */
276         s->prio[15-(offset>>2)] = val;
277         break;
278 
279         /* Read-only registers, writes ignored */
280     case 16:/* Normal Interrupt Vector and Status register */
281     case 17:/* Fast Interrupt vector and status register */
282     case 18:/* Interrupt source register high */
283     case 19:/* Interrupt source register low */
284         return;
285 
286     case 20:/* Interrupt Force Register high */
287         s->pending = (s->pending & 0xffffffffULL) | (val << 32);
288         break;
289 
290     case 21:/* Interrupt Force Register low */
291         s->pending = (s->pending & 0xffffffff00000000ULL) | val;
292         break;
293 
294     case 22:/* Normal Interrupt Pending Register High */
295     case 23:/* Normal Interrupt Pending Register Low */
296     case 24: /* Fast Interrupt Pending Register High  */
297     case 25: /* Fast Interrupt Pending Register Low  */
298         return;
299 
300     default:
301         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
302                       HWADDR_PRIx "\n", TYPE_IMX_AVIC, __func__, offset);
303     }
304     imx_avic_update(s);
305 }
306 
307 static const MemoryRegionOps imx_avic_ops = {
308     .read = imx_avic_read,
309     .write = imx_avic_write,
310     .endianness = DEVICE_NATIVE_ENDIAN,
311 };
312 
313 static void imx_avic_reset(DeviceState *dev)
314 {
315     IMXAVICState *s = IMX_AVIC(dev);
316 
317     s->pending = 0;
318     s->enabled = 0;
319     s->is_fiq = 0;
320     s->intmask = 0x1f;
321     s->intcntl = 0;
322     memset(s->prio, 0, sizeof s->prio);
323 }
324 
325 static void imx_avic_init(Object *obj)
326 {
327     DeviceState *dev = DEVICE(obj);
328     IMXAVICState *s = IMX_AVIC(obj);
329     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
330 
331     memory_region_init_io(&s->iomem, obj, &imx_avic_ops, s,
332                           TYPE_IMX_AVIC, 0x1000);
333     sysbus_init_mmio(sbd, &s->iomem);
334 
335     qdev_init_gpio_in(dev, imx_avic_set_irq, IMX_AVIC_NUM_IRQS);
336     sysbus_init_irq(sbd, &s->irq);
337     sysbus_init_irq(sbd, &s->fiq);
338 }
339 
340 
341 static void imx_avic_class_init(ObjectClass *klass, void *data)
342 {
343     DeviceClass *dc = DEVICE_CLASS(klass);
344 
345     dc->vmsd = &vmstate_imx_avic;
346     dc->reset = imx_avic_reset;
347     dc->desc = "i.MX Advanced Vector Interrupt Controller";
348 }
349 
350 static const TypeInfo imx_avic_info = {
351     .name = TYPE_IMX_AVIC,
352     .parent = TYPE_SYS_BUS_DEVICE,
353     .instance_size = sizeof(IMXAVICState),
354     .instance_init = imx_avic_init,
355     .class_init = imx_avic_class_init,
356 };
357 
358 static void imx_avic_register_types(void)
359 {
360     type_register_static(&imx_avic_info);
361 }
362 
363 type_init(imx_avic_register_types)
364