xref: /openbmc/qemu/hw/intc/sh_intc.c (revision 56983463)
1 /*
2  * SuperH interrupt controller module
3  *
4  * Copyright (c) 2007 Magnus Damm
5  * Based on sh_timer.c and arm_timer.c by Paul Brook
6  * Copyright (c) 2005-2006 CodeSourcery.
7  *
8  * This code is licensed under the GPL.
9  */
10 
11 #include "hw/sh4/sh_intc.h"
12 #include "hw/hw.h"
13 #include "hw/sh4/sh.h"
14 
15 //#define DEBUG_INTC
16 //#define DEBUG_INTC_SOURCES
17 
18 #define INTC_A7(x) ((x) & 0x1fffffff)
19 
20 void sh_intc_toggle_source(struct intc_source *source,
21 			   int enable_adj, int assert_adj)
22 {
23     int enable_changed = 0;
24     int pending_changed = 0;
25     int old_pending;
26 
27     if ((source->enable_count == source->enable_max) && (enable_adj == -1))
28         enable_changed = -1;
29 
30     source->enable_count += enable_adj;
31 
32     if (source->enable_count == source->enable_max)
33         enable_changed = 1;
34 
35     source->asserted += assert_adj;
36 
37     old_pending = source->pending;
38     source->pending = source->asserted &&
39       (source->enable_count == source->enable_max);
40 
41     if (old_pending != source->pending)
42         pending_changed = 1;
43 
44     if (pending_changed) {
45         if (source->pending) {
46             source->parent->pending++;
47             if (source->parent->pending == 1) {
48                 cpu_interrupt(first_cpu, CPU_INTERRUPT_HARD);
49             }
50         } else {
51             source->parent->pending--;
52             if (source->parent->pending == 0) {
53                 cpu_reset_interrupt(first_cpu, CPU_INTERRUPT_HARD);
54             }
55 	}
56     }
57 
58   if (enable_changed || assert_adj || pending_changed) {
59 #ifdef DEBUG_INTC_SOURCES
60             printf("sh_intc: (%d/%d/%d/%d) interrupt source 0x%x %s%s%s\n",
61 		   source->parent->pending,
62 		   source->asserted,
63 		   source->enable_count,
64 		   source->enable_max,
65 		   source->vect,
66 		   source->asserted ? "asserted " :
67 		   assert_adj ? "deasserted" : "",
68 		   enable_changed == 1 ? "enabled " :
69 		   enable_changed == -1 ? "disabled " : "",
70 		   source->pending ? "pending" : "");
71 #endif
72   }
73 }
74 
75 static void sh_intc_set_irq (void *opaque, int n, int level)
76 {
77   struct intc_desc *desc = opaque;
78   struct intc_source *source = &(desc->sources[n]);
79 
80   if (level && !source->asserted)
81     sh_intc_toggle_source(source, 0, 1);
82   else if (!level && source->asserted)
83     sh_intc_toggle_source(source, 0, -1);
84 }
85 
86 int sh_intc_get_pending_vector(struct intc_desc *desc, int imask)
87 {
88     unsigned int i;
89 
90     /* slow: use a linked lists of pending sources instead */
91     /* wrong: take interrupt priority into account (one list per priority) */
92 
93     if (imask == 0x0f) {
94         return -1; /* FIXME, update code to include priority per source */
95     }
96 
97     for (i = 0; i < desc->nr_sources; i++) {
98         struct intc_source *source = desc->sources + i;
99 
100 	if (source->pending) {
101 #ifdef DEBUG_INTC_SOURCES
102             printf("sh_intc: (%d) returning interrupt source 0x%x\n",
103 		   desc->pending, source->vect);
104 #endif
105             return source->vect;
106 	}
107     }
108 
109     abort();
110 }
111 
112 #define INTC_MODE_NONE       0
113 #define INTC_MODE_DUAL_SET   1
114 #define INTC_MODE_DUAL_CLR   2
115 #define INTC_MODE_ENABLE_REG 3
116 #define INTC_MODE_MASK_REG   4
117 #define INTC_MODE_IS_PRIO    8
118 
119 static unsigned int sh_intc_mode(unsigned long address,
120 				 unsigned long set_reg, unsigned long clr_reg)
121 {
122     if ((address != INTC_A7(set_reg)) &&
123 	(address != INTC_A7(clr_reg)))
124         return INTC_MODE_NONE;
125 
126     if (set_reg && clr_reg) {
127         if (address == INTC_A7(set_reg))
128             return INTC_MODE_DUAL_SET;
129 	else
130             return INTC_MODE_DUAL_CLR;
131     }
132 
133     if (set_reg)
134         return INTC_MODE_ENABLE_REG;
135     else
136         return INTC_MODE_MASK_REG;
137 }
138 
139 static void sh_intc_locate(struct intc_desc *desc,
140 			   unsigned long address,
141 			   unsigned long **datap,
142 			   intc_enum **enums,
143 			   unsigned int *first,
144 			   unsigned int *width,
145 			   unsigned int *modep)
146 {
147     unsigned int i, mode;
148 
149     /* this is slow but works for now */
150 
151     if (desc->mask_regs) {
152         for (i = 0; i < desc->nr_mask_regs; i++) {
153 	    struct intc_mask_reg *mr = desc->mask_regs + i;
154 
155 	    mode = sh_intc_mode(address, mr->set_reg, mr->clr_reg);
156 	    if (mode == INTC_MODE_NONE)
157                 continue;
158 
159 	    *modep = mode;
160 	    *datap = &mr->value;
161 	    *enums = mr->enum_ids;
162 	    *first = mr->reg_width - 1;
163 	    *width = 1;
164 	    return;
165 	}
166     }
167 
168     if (desc->prio_regs) {
169         for (i = 0; i < desc->nr_prio_regs; i++) {
170 	    struct intc_prio_reg *pr = desc->prio_regs + i;
171 
172 	    mode = sh_intc_mode(address, pr->set_reg, pr->clr_reg);
173 	    if (mode == INTC_MODE_NONE)
174                 continue;
175 
176 	    *modep = mode | INTC_MODE_IS_PRIO;
177 	    *datap = &pr->value;
178 	    *enums = pr->enum_ids;
179 	    *first = (pr->reg_width / pr->field_width) - 1;
180 	    *width = pr->field_width;
181 	    return;
182 	}
183     }
184 
185     abort();
186 }
187 
188 static void sh_intc_toggle_mask(struct intc_desc *desc, intc_enum id,
189 				int enable, int is_group)
190 {
191     struct intc_source *source = desc->sources + id;
192 
193     if (!id)
194 	return;
195 
196     if (!source->next_enum_id && (!source->enable_max || !source->vect)) {
197 #ifdef DEBUG_INTC_SOURCES
198         printf("sh_intc: reserved interrupt source %d modified\n", id);
199 #endif
200 	return;
201     }
202 
203     if (source->vect)
204         sh_intc_toggle_source(source, enable ? 1 : -1, 0);
205 
206 #ifdef DEBUG_INTC
207     else {
208         printf("setting interrupt group %d to %d\n", id, !!enable);
209     }
210 #endif
211 
212     if ((is_group || !source->vect) && source->next_enum_id) {
213         sh_intc_toggle_mask(desc, source->next_enum_id, enable, 1);
214     }
215 
216 #ifdef DEBUG_INTC
217     if (!source->vect) {
218         printf("setting interrupt group %d to %d - done\n", id, !!enable);
219     }
220 #endif
221 }
222 
223 static uint64_t sh_intc_read(void *opaque, hwaddr offset,
224                              unsigned size)
225 {
226     struct intc_desc *desc = opaque;
227     intc_enum *enum_ids = NULL;
228     unsigned int first = 0;
229     unsigned int width = 0;
230     unsigned int mode = 0;
231     unsigned long *valuep;
232 
233 #ifdef DEBUG_INTC
234     printf("sh_intc_read 0x%lx\n", (unsigned long) offset);
235 #endif
236 
237     sh_intc_locate(desc, (unsigned long)offset, &valuep,
238 		   &enum_ids, &first, &width, &mode);
239     return *valuep;
240 }
241 
242 static void sh_intc_write(void *opaque, hwaddr offset,
243                           uint64_t value, unsigned size)
244 {
245     struct intc_desc *desc = opaque;
246     intc_enum *enum_ids = NULL;
247     unsigned int first = 0;
248     unsigned int width = 0;
249     unsigned int mode = 0;
250     unsigned int k;
251     unsigned long *valuep;
252     unsigned long mask;
253 
254 #ifdef DEBUG_INTC
255     printf("sh_intc_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
256 #endif
257 
258     sh_intc_locate(desc, (unsigned long)offset, &valuep,
259 		   &enum_ids, &first, &width, &mode);
260 
261     switch (mode) {
262     case INTC_MODE_ENABLE_REG | INTC_MODE_IS_PRIO: break;
263     case INTC_MODE_DUAL_SET: value |= *valuep; break;
264     case INTC_MODE_DUAL_CLR: value = *valuep & ~value; break;
265     default: abort();
266     }
267 
268     for (k = 0; k <= first; k++) {
269         mask = ((1 << width) - 1) << ((first - k) * width);
270 
271 	if ((*valuep & mask) == (value & mask))
272             continue;
273 #if 0
274 	printf("k = %d, first = %d, enum = %d, mask = 0x%08x\n",
275 	       k, first, enum_ids[k], (unsigned int)mask);
276 #endif
277         sh_intc_toggle_mask(desc, enum_ids[k], value & mask, 0);
278     }
279 
280     *valuep = value;
281 
282 #ifdef DEBUG_INTC
283     printf("sh_intc_write 0x%lx -> 0x%08x\n", (unsigned long) offset, value);
284 #endif
285 }
286 
287 static const MemoryRegionOps sh_intc_ops = {
288     .read = sh_intc_read,
289     .write = sh_intc_write,
290     .endianness = DEVICE_NATIVE_ENDIAN,
291 };
292 
293 struct intc_source *sh_intc_source(struct intc_desc *desc, intc_enum id)
294 {
295     if (id)
296         return desc->sources + id;
297 
298     return NULL;
299 }
300 
301 static unsigned int sh_intc_register(MemoryRegion *sysmem,
302                              struct intc_desc *desc,
303                              const unsigned long address,
304                              const char *type,
305                              const char *action,
306                              const unsigned int index)
307 {
308     char name[60];
309     MemoryRegion *iomem, *iomem_p4, *iomem_a7;
310 
311     if (!address) {
312         return 0;
313     }
314 
315     iomem = &desc->iomem;
316     iomem_p4 = desc->iomem_aliases + index;
317     iomem_a7 = iomem_p4 + 1;
318 
319 #define SH_INTC_IOMEM_FORMAT "interrupt-controller-%s-%s-%s"
320     snprintf(name, sizeof(name), SH_INTC_IOMEM_FORMAT, type, action, "p4");
321     memory_region_init_alias(iomem_p4, NULL, name, iomem, INTC_A7(address), 4);
322     memory_region_add_subregion(sysmem, P4ADDR(address), iomem_p4);
323 
324     snprintf(name, sizeof(name), SH_INTC_IOMEM_FORMAT, type, action, "a7");
325     memory_region_init_alias(iomem_a7, NULL, name, iomem, INTC_A7(address), 4);
326     memory_region_add_subregion(sysmem, A7ADDR(address), iomem_a7);
327 #undef SH_INTC_IOMEM_FORMAT
328 
329     /* used to increment aliases index */
330     return 2;
331 }
332 
333 static void sh_intc_register_source(struct intc_desc *desc,
334 				    intc_enum source,
335 				    struct intc_group *groups,
336 				    int nr_groups)
337 {
338     unsigned int i, k;
339     struct intc_source *s;
340 
341     if (desc->mask_regs) {
342         for (i = 0; i < desc->nr_mask_regs; i++) {
343 	    struct intc_mask_reg *mr = desc->mask_regs + i;
344 
345 	    for (k = 0; k < ARRAY_SIZE(mr->enum_ids); k++) {
346                 if (mr->enum_ids[k] != source)
347                     continue;
348 
349 		s = sh_intc_source(desc, mr->enum_ids[k]);
350 		if (s)
351                     s->enable_max++;
352 	    }
353 	}
354     }
355 
356     if (desc->prio_regs) {
357         for (i = 0; i < desc->nr_prio_regs; i++) {
358 	    struct intc_prio_reg *pr = desc->prio_regs + i;
359 
360 	    for (k = 0; k < ARRAY_SIZE(pr->enum_ids); k++) {
361                 if (pr->enum_ids[k] != source)
362                     continue;
363 
364 		s = sh_intc_source(desc, pr->enum_ids[k]);
365 		if (s)
366                     s->enable_max++;
367 	    }
368 	}
369     }
370 
371     if (groups) {
372         for (i = 0; i < nr_groups; i++) {
373 	    struct intc_group *gr = groups + i;
374 
375 	    for (k = 0; k < ARRAY_SIZE(gr->enum_ids); k++) {
376                 if (gr->enum_ids[k] != source)
377                     continue;
378 
379 		s = sh_intc_source(desc, gr->enum_ids[k]);
380 		if (s)
381                     s->enable_max++;
382 	    }
383 	}
384     }
385 
386 }
387 
388 void sh_intc_register_sources(struct intc_desc *desc,
389 			      struct intc_vect *vectors,
390 			      int nr_vectors,
391 			      struct intc_group *groups,
392 			      int nr_groups)
393 {
394     unsigned int i, k;
395     struct intc_source *s;
396 
397     for (i = 0; i < nr_vectors; i++) {
398 	struct intc_vect *vect = vectors + i;
399 
400 	sh_intc_register_source(desc, vect->enum_id, groups, nr_groups);
401 	s = sh_intc_source(desc, vect->enum_id);
402         if (s) {
403             s->vect = vect->vect;
404 
405 #ifdef DEBUG_INTC_SOURCES
406             printf("sh_intc: registered source %d -> 0x%04x (%d/%d)\n",
407                    vect->enum_id, s->vect, s->enable_count, s->enable_max);
408 #endif
409         }
410     }
411 
412     if (groups) {
413         for (i = 0; i < nr_groups; i++) {
414 	    struct intc_group *gr = groups + i;
415 
416 	    s = sh_intc_source(desc, gr->enum_id);
417 	    s->next_enum_id = gr->enum_ids[0];
418 
419 	    for (k = 1; k < ARRAY_SIZE(gr->enum_ids); k++) {
420                 if (!gr->enum_ids[k])
421                     continue;
422 
423 		s = sh_intc_source(desc, gr->enum_ids[k - 1]);
424 		s->next_enum_id = gr->enum_ids[k];
425 	    }
426 
427 #ifdef DEBUG_INTC_SOURCES
428 	    printf("sh_intc: registered group %d (%d/%d)\n",
429 		   gr->enum_id, s->enable_count, s->enable_max);
430 #endif
431 	}
432     }
433 }
434 
435 int sh_intc_init(MemoryRegion *sysmem,
436          struct intc_desc *desc,
437 		 int nr_sources,
438 		 struct intc_mask_reg *mask_regs,
439 		 int nr_mask_regs,
440 		 struct intc_prio_reg *prio_regs,
441 		 int nr_prio_regs)
442 {
443     unsigned int i, j;
444 
445     desc->pending = 0;
446     desc->nr_sources = nr_sources;
447     desc->mask_regs = mask_regs;
448     desc->nr_mask_regs = nr_mask_regs;
449     desc->prio_regs = prio_regs;
450     desc->nr_prio_regs = nr_prio_regs;
451     /* Allocate 4 MemoryRegions per register (2 actions * 2 aliases).
452      **/
453     desc->iomem_aliases = g_new0(MemoryRegion,
454                                  (nr_mask_regs + nr_prio_regs) * 4);
455 
456     j = 0;
457     i = sizeof(struct intc_source) * nr_sources;
458     desc->sources = g_malloc0(i);
459 
460     for (i = 0; i < desc->nr_sources; i++) {
461         struct intc_source *source = desc->sources + i;
462 
463         source->parent = desc;
464     }
465 
466     desc->irqs = qemu_allocate_irqs(sh_intc_set_irq, desc, nr_sources);
467 
468     memory_region_init_io(&desc->iomem, NULL, &sh_intc_ops, desc,
469                           "interrupt-controller", 0x100000000ULL);
470 
471 #define INT_REG_PARAMS(reg_struct, type, action, j) \
472         reg_struct->action##_reg, #type, #action, j
473     if (desc->mask_regs) {
474         for (i = 0; i < desc->nr_mask_regs; i++) {
475 	    struct intc_mask_reg *mr = desc->mask_regs + i;
476 
477             j += sh_intc_register(sysmem, desc,
478                                   INT_REG_PARAMS(mr, mask, set, j));
479             j += sh_intc_register(sysmem, desc,
480                                   INT_REG_PARAMS(mr, mask, clr, j));
481 	}
482     }
483 
484     if (desc->prio_regs) {
485         for (i = 0; i < desc->nr_prio_regs; i++) {
486 	    struct intc_prio_reg *pr = desc->prio_regs + i;
487 
488             j += sh_intc_register(sysmem, desc,
489                                   INT_REG_PARAMS(pr, prio, set, j));
490             j += sh_intc_register(sysmem, desc,
491                                   INT_REG_PARAMS(pr, prio, clr, j));
492 	}
493     }
494 #undef INT_REG_PARAMS
495 
496     return 0;
497 }
498 
499 /* Assert level <n> IRL interrupt.
500    0:deassert. 1:lowest priority,... 15:highest priority. */
501 void sh_intc_set_irl(void *opaque, int n, int level)
502 {
503     struct intc_source *s = opaque;
504     int i, irl = level ^ 15;
505     for (i = 0; (s = sh_intc_source(s->parent, s->next_enum_id)); i++) {
506 	if (i == irl)
507 	    sh_intc_toggle_source(s, s->enable_count?0:1, s->asserted?0:1);
508 	else
509 	    if (s->asserted)
510 	        sh_intc_toggle_source(s, 0, -1);
511     }
512 }
513