xref: /openbmc/qemu/hw/intc/imx_avic.c (revision f250c6a7510e0069fdc7fd1fb76700db4daa9ddd)
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 "hw/intc/imx_avic.h"
19 
20 #define DEBUG_INT 1
21 #undef DEBUG_INT /* comment out for debugging */
22 
23 #ifdef DEBUG_INT
24 #define DPRINTF(fmt, args...) \
25 do { printf("imx_avic: " fmt , ##args); } while (0)
26 #else
27 #define DPRINTF(fmt, args...) do {} while (0)
28 #endif
29 
30 /*
31  * Define to 1 for messages about attempts to
32  * access unimplemented registers or similar.
33  */
34 #define DEBUG_IMPLEMENTATION 1
35 #if DEBUG_IMPLEMENTATION
36 #  define IPRINTF(fmt, args...) \
37     do  { fprintf(stderr, "imx_avic: " fmt, ##args); } while (0)
38 #else
39 #  define IPRINTF(fmt, args...) do {} while (0)
40 #endif
41 
42 static const VMStateDescription vmstate_imx_avic = {
43     .name = "imx-avic",
44     .version_id = 1,
45     .minimum_version_id = 1,
46     .fields = (VMStateField[]) {
47         VMSTATE_UINT64(pending, IMXAVICState),
48         VMSTATE_UINT64(enabled, IMXAVICState),
49         VMSTATE_UINT64(is_fiq, IMXAVICState),
50         VMSTATE_UINT32(intcntl, IMXAVICState),
51         VMSTATE_UINT32(intmask, IMXAVICState),
52         VMSTATE_UINT32_ARRAY(prio, IMXAVICState, PRIO_WORDS),
53         VMSTATE_END_OF_LIST()
54     },
55 };
56 
57 
58 
59 static inline int imx_avic_prio(IMXAVICState *s, int irq)
60 {
61     uint32_t word = irq / PRIO_PER_WORD;
62     uint32_t part = 4 * (irq % PRIO_PER_WORD);
63     return 0xf & (s->prio[word] >> part);
64 }
65 
66 /* Update interrupts.  */
67 static void imx_avic_update(IMXAVICState *s)
68 {
69     int i;
70     uint64_t new = s->pending & s->enabled;
71     uint64_t flags;
72 
73     flags = new & s->is_fiq;
74     qemu_set_irq(s->fiq, !!flags);
75 
76     flags = new & ~s->is_fiq;
77     if (!flags || (s->intmask == 0x1f)) {
78         qemu_set_irq(s->irq, !!flags);
79         return;
80     }
81 
82     /*
83      * Take interrupt if there's a pending interrupt with
84      * priority higher than the value of intmask
85      */
86     for (i = 0; i < IMX_AVIC_NUM_IRQS; i++) {
87         if (flags & (1UL << i)) {
88             if (imx_avic_prio(s, i) > s->intmask) {
89                 qemu_set_irq(s->irq, 1);
90                 return;
91             }
92         }
93     }
94     qemu_set_irq(s->irq, 0);
95 }
96 
97 static void imx_avic_set_irq(void *opaque, int irq, int level)
98 {
99     IMXAVICState *s = (IMXAVICState *)opaque;
100 
101     if (level) {
102         DPRINTF("Raising IRQ %d, prio %d\n",
103                 irq, imx_avic_prio(s, irq));
104         s->pending |= (1ULL << irq);
105     } else {
106         DPRINTF("Clearing IRQ %d, prio %d\n",
107                 irq, imx_avic_prio(s, irq));
108         s->pending &= ~(1ULL << irq);
109     }
110 
111     imx_avic_update(s);
112 }
113 
114 
115 static uint64_t imx_avic_read(void *opaque,
116                              hwaddr offset, unsigned size)
117 {
118     IMXAVICState *s = (IMXAVICState *)opaque;
119 
120 
121     DPRINTF("read(offset = 0x%x)\n", offset >> 2);
122     switch (offset >> 2) {
123     case 0: /* INTCNTL */
124         return s->intcntl;
125 
126     case 1: /* Normal Interrupt Mask Register, NIMASK */
127         return s->intmask;
128 
129     case 2: /* Interrupt Enable Number Register, INTENNUM */
130     case 3: /* Interrupt Disable Number Register, INTDISNUM */
131         return 0;
132 
133     case 4: /* Interrupt Enabled Number Register High */
134         return s->enabled >> 32;
135 
136     case 5: /* Interrupt Enabled Number Register Low */
137         return s->enabled & 0xffffffffULL;
138 
139     case 6: /* Interrupt Type Register High */
140         return s->is_fiq >> 32;
141 
142     case 7: /* Interrupt Type Register Low */
143         return s->is_fiq & 0xffffffffULL;
144 
145     case 8: /* Normal Interrupt Priority Register 7 */
146     case 9: /* Normal Interrupt Priority Register 6 */
147     case 10:/* Normal Interrupt Priority Register 5 */
148     case 11:/* Normal Interrupt Priority Register 4 */
149     case 12:/* Normal Interrupt Priority Register 3 */
150     case 13:/* Normal Interrupt Priority Register 2 */
151     case 14:/* Normal Interrupt Priority Register 1 */
152     case 15:/* Normal Interrupt Priority Register 0 */
153         return s->prio[15-(offset>>2)];
154 
155     case 16: /* Normal interrupt vector and status register */
156     {
157         /*
158          * This returns the highest priority
159          * outstanding interrupt.  Where there is more than
160          * one pending IRQ with the same priority,
161          * take the highest numbered one.
162          */
163         uint64_t flags = s->pending & s->enabled & ~s->is_fiq;
164         int i;
165         int prio = -1;
166         int irq = -1;
167         for (i = 63; i >= 0; --i) {
168             if (flags & (1ULL<<i)) {
169                 int irq_prio = imx_avic_prio(s, i);
170                 if (irq_prio > prio) {
171                     irq = i;
172                     prio = irq_prio;
173                 }
174             }
175         }
176         if (irq >= 0) {
177             imx_avic_set_irq(s, irq, 0);
178             return irq << 16 | prio;
179         }
180         return 0xffffffffULL;
181     }
182     case 17:/* Fast Interrupt vector and status register */
183     {
184         uint64_t flags = s->pending & s->enabled & s->is_fiq;
185         int i = ctz64(flags);
186         if (i < 64) {
187             imx_avic_set_irq(opaque, i, 0);
188             return i;
189         }
190         return 0xffffffffULL;
191     }
192     case 18:/* Interrupt source register high */
193         return s->pending >> 32;
194 
195     case 19:/* Interrupt source register low */
196         return s->pending & 0xffffffffULL;
197 
198     case 20:/* Interrupt Force Register high */
199     case 21:/* Interrupt Force Register low */
200         return 0;
201 
202     case 22:/* Normal Interrupt Pending Register High */
203         return (s->pending & s->enabled & ~s->is_fiq) >> 32;
204 
205     case 23:/* Normal Interrupt Pending Register Low */
206         return (s->pending & s->enabled & ~s->is_fiq) & 0xffffffffULL;
207 
208     case 24: /* Fast Interrupt Pending Register High  */
209         return (s->pending & s->enabled & s->is_fiq) >> 32;
210 
211     case 25: /* Fast Interrupt Pending Register Low  */
212         return (s->pending & s->enabled & s->is_fiq) & 0xffffffffULL;
213 
214     case 0x40:            /* AVIC vector 0, use for WFI WAR */
215         return 0x4;
216 
217     default:
218         IPRINTF("imx_avic_read: Bad offset 0x%x\n", (int)offset);
219         return 0;
220     }
221 }
222 
223 static void imx_avic_write(void *opaque, hwaddr offset,
224                           uint64_t val, unsigned size)
225 {
226     IMXAVICState *s = (IMXAVICState *)opaque;
227 
228     /* Vector Registers not yet supported */
229     if (offset >= 0x100 && offset <= 0x2fc) {
230         IPRINTF("imx_avic_write to vector register %d ignored\n",
231                 (unsigned int)((offset - 0x100) >> 2));
232         return;
233     }
234 
235     DPRINTF("imx_avic_write(0x%x) = %x\n",
236             (unsigned int)offset>>2, (unsigned int)val);
237     switch (offset >> 2) {
238     case 0: /* Interrupt Control Register, INTCNTL */
239         s->intcntl = val & (ABFEN | NIDIS | FIDIS | NIAD | FIAD | NM);
240         if (s->intcntl & ABFEN) {
241             s->intcntl &= ~(val & ABFLAG);
242         }
243         break;
244 
245     case 1: /* Normal Interrupt Mask Register, NIMASK */
246         s->intmask = val & 0x1f;
247         break;
248 
249     case 2: /* Interrupt Enable Number Register, INTENNUM */
250         DPRINTF("enable(%d)\n", (int)val);
251         val &= 0x3f;
252         s->enabled |= (1ULL << val);
253         break;
254 
255     case 3: /* Interrupt Disable Number Register, INTDISNUM */
256         DPRINTF("disable(%d)\n", (int)val);
257         val &= 0x3f;
258         s->enabled &= ~(1ULL << val);
259         break;
260 
261     case 4: /* Interrupt Enable Number Register High */
262         s->enabled = (s->enabled & 0xffffffffULL) | (val << 32);
263         break;
264 
265     case 5: /* Interrupt Enable Number Register Low */
266         s->enabled = (s->enabled & 0xffffffff00000000ULL) | val;
267         break;
268 
269     case 6: /* Interrupt Type Register High */
270         s->is_fiq = (s->is_fiq & 0xffffffffULL) | (val << 32);
271         break;
272 
273     case 7: /* Interrupt Type Register Low */
274         s->is_fiq = (s->is_fiq & 0xffffffff00000000ULL) | val;
275         break;
276 
277     case 8: /* Normal Interrupt Priority Register 7 */
278     case 9: /* Normal Interrupt Priority Register 6 */
279     case 10:/* Normal Interrupt Priority Register 5 */
280     case 11:/* Normal Interrupt Priority Register 4 */
281     case 12:/* Normal Interrupt Priority Register 3 */
282     case 13:/* Normal Interrupt Priority Register 2 */
283     case 14:/* Normal Interrupt Priority Register 1 */
284     case 15:/* Normal Interrupt Priority Register 0 */
285         s->prio[15-(offset>>2)] = val;
286         break;
287 
288         /* Read-only registers, writes ignored */
289     case 16:/* Normal Interrupt Vector and Status register */
290     case 17:/* Fast Interrupt vector and status register */
291     case 18:/* Interrupt source register high */
292     case 19:/* Interrupt source register low */
293         return;
294 
295     case 20:/* Interrupt Force Register high */
296         s->pending = (s->pending & 0xffffffffULL) | (val << 32);
297         break;
298 
299     case 21:/* Interrupt Force Register low */
300         s->pending = (s->pending & 0xffffffff00000000ULL) | val;
301         break;
302 
303     case 22:/* Normal Interrupt Pending Register High */
304     case 23:/* Normal Interrupt Pending Register Low */
305     case 24: /* Fast Interrupt Pending Register High  */
306     case 25: /* Fast Interrupt Pending Register Low  */
307         return;
308 
309     default:
310         IPRINTF("imx_avic_write: Bad offset %x\n", (int)offset);
311     }
312     imx_avic_update(s);
313 }
314 
315 static const MemoryRegionOps imx_avic_ops = {
316     .read = imx_avic_read,
317     .write = imx_avic_write,
318     .endianness = DEVICE_NATIVE_ENDIAN,
319 };
320 
321 static void imx_avic_reset(DeviceState *dev)
322 {
323     IMXAVICState *s = IMX_AVIC(dev);
324 
325     s->pending = 0;
326     s->enabled = 0;
327     s->is_fiq = 0;
328     s->intmask = 0x1f;
329     s->intcntl = 0;
330     memset(s->prio, 0, sizeof s->prio);
331 }
332 
333 static int imx_avic_init(SysBusDevice *sbd)
334 {
335     DeviceState *dev = DEVICE(sbd);
336     IMXAVICState *s = IMX_AVIC(dev);
337 
338     memory_region_init_io(&s->iomem, OBJECT(s), &imx_avic_ops, s,
339                           TYPE_IMX_AVIC, 0x1000);
340     sysbus_init_mmio(sbd, &s->iomem);
341 
342     qdev_init_gpio_in(dev, imx_avic_set_irq, IMX_AVIC_NUM_IRQS);
343     sysbus_init_irq(sbd, &s->irq);
344     sysbus_init_irq(sbd, &s->fiq);
345 
346     return 0;
347 }
348 
349 
350 static void imx_avic_class_init(ObjectClass *klass, void *data)
351 {
352     DeviceClass *dc = DEVICE_CLASS(klass);
353     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
354     k->init = imx_avic_init;
355     dc->vmsd = &vmstate_imx_avic;
356     dc->reset = imx_avic_reset;
357     dc->desc = "i.MX Advanced Vector Interrupt Controller";
358 }
359 
360 static const TypeInfo imx_avic_info = {
361     .name = TYPE_IMX_AVIC,
362     .parent = TYPE_SYS_BUS_DEVICE,
363     .instance_size = sizeof(IMXAVICState),
364     .class_init = imx_avic_class_init,
365 };
366 
367 static void imx_avic_register_types(void)
368 {
369     type_register_static(&imx_avic_info);
370 }
371 
372 type_init(imx_avic_register_types)
373