xref: /openbmc/qemu/hw/intc/sh_intc.c (revision 59a3a1c0)
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 "qemu/osdep.h"
12 #include "cpu.h"
13 #include "hw/sh4/sh_intc.h"
14 #include "hw/irq.h"
15 #include "hw/sh4/sh.h"
16 
17 //#define DEBUG_INTC
18 //#define DEBUG_INTC_SOURCES
19 
20 #define INTC_A7(x) ((x) & 0x1fffffff)
21 
22 void sh_intc_toggle_source(struct intc_source *source,
23 			   int enable_adj, int assert_adj)
24 {
25     int enable_changed = 0;
26     int pending_changed = 0;
27     int old_pending;
28 
29     if ((source->enable_count == source->enable_max) && (enable_adj == -1))
30         enable_changed = -1;
31 
32     source->enable_count += enable_adj;
33 
34     if (source->enable_count == source->enable_max)
35         enable_changed = 1;
36 
37     source->asserted += assert_adj;
38 
39     old_pending = source->pending;
40     source->pending = source->asserted &&
41       (source->enable_count == source->enable_max);
42 
43     if (old_pending != source->pending)
44         pending_changed = 1;
45 
46     if (pending_changed) {
47         if (source->pending) {
48             source->parent->pending++;
49             if (source->parent->pending == 1) {
50                 cpu_interrupt(first_cpu, CPU_INTERRUPT_HARD);
51             }
52         } else {
53             source->parent->pending--;
54             if (source->parent->pending == 0) {
55                 cpu_reset_interrupt(first_cpu, CPU_INTERRUPT_HARD);
56             }
57 	}
58     }
59 
60   if (enable_changed || assert_adj || pending_changed) {
61 #ifdef DEBUG_INTC_SOURCES
62             printf("sh_intc: (%d/%d/%d/%d) interrupt source 0x%x %s%s%s\n",
63 		   source->parent->pending,
64 		   source->asserted,
65 		   source->enable_count,
66 		   source->enable_max,
67 		   source->vect,
68 		   source->asserted ? "asserted " :
69 		   assert_adj ? "deasserted" : "",
70 		   enable_changed == 1 ? "enabled " :
71 		   enable_changed == -1 ? "disabled " : "",
72 		   source->pending ? "pending" : "");
73 #endif
74   }
75 }
76 
77 static void sh_intc_set_irq (void *opaque, int n, int level)
78 {
79   struct intc_desc *desc = opaque;
80   struct intc_source *source = &(desc->sources[n]);
81 
82   if (level && !source->asserted)
83     sh_intc_toggle_source(source, 0, 1);
84   else if (!level && source->asserted)
85     sh_intc_toggle_source(source, 0, -1);
86 }
87 
88 int sh_intc_get_pending_vector(struct intc_desc *desc, int imask)
89 {
90     unsigned int i;
91 
92     /* slow: use a linked lists of pending sources instead */
93     /* wrong: take interrupt priority into account (one list per priority) */
94 
95     if (imask == 0x0f) {
96         return -1; /* FIXME, update code to include priority per source */
97     }
98 
99     for (i = 0; i < desc->nr_sources; i++) {
100         struct intc_source *source = desc->sources + i;
101 
102 	if (source->pending) {
103 #ifdef DEBUG_INTC_SOURCES
104             printf("sh_intc: (%d) returning interrupt source 0x%x\n",
105 		   desc->pending, source->vect);
106 #endif
107             return source->vect;
108 	}
109     }
110 
111     abort();
112 }
113 
114 #define INTC_MODE_NONE       0
115 #define INTC_MODE_DUAL_SET   1
116 #define INTC_MODE_DUAL_CLR   2
117 #define INTC_MODE_ENABLE_REG 3
118 #define INTC_MODE_MASK_REG   4
119 #define INTC_MODE_IS_PRIO    8
120 
121 static unsigned int sh_intc_mode(unsigned long address,
122 				 unsigned long set_reg, unsigned long clr_reg)
123 {
124     if ((address != INTC_A7(set_reg)) &&
125 	(address != INTC_A7(clr_reg)))
126         return INTC_MODE_NONE;
127 
128     if (set_reg && clr_reg) {
129         if (address == INTC_A7(set_reg))
130             return INTC_MODE_DUAL_SET;
131 	else
132             return INTC_MODE_DUAL_CLR;
133     }
134 
135     if (set_reg)
136         return INTC_MODE_ENABLE_REG;
137     else
138         return INTC_MODE_MASK_REG;
139 }
140 
141 static void sh_intc_locate(struct intc_desc *desc,
142 			   unsigned long address,
143 			   unsigned long **datap,
144 			   intc_enum **enums,
145 			   unsigned int *first,
146 			   unsigned int *width,
147 			   unsigned int *modep)
148 {
149     unsigned int i, mode;
150 
151     /* this is slow but works for now */
152 
153     if (desc->mask_regs) {
154         for (i = 0; i < desc->nr_mask_regs; i++) {
155 	    struct intc_mask_reg *mr = desc->mask_regs + i;
156 
157 	    mode = sh_intc_mode(address, mr->set_reg, mr->clr_reg);
158 	    if (mode == INTC_MODE_NONE)
159                 continue;
160 
161 	    *modep = mode;
162 	    *datap = &mr->value;
163 	    *enums = mr->enum_ids;
164 	    *first = mr->reg_width - 1;
165 	    *width = 1;
166 	    return;
167 	}
168     }
169 
170     if (desc->prio_regs) {
171         for (i = 0; i < desc->nr_prio_regs; i++) {
172 	    struct intc_prio_reg *pr = desc->prio_regs + i;
173 
174 	    mode = sh_intc_mode(address, pr->set_reg, pr->clr_reg);
175 	    if (mode == INTC_MODE_NONE)
176                 continue;
177 
178 	    *modep = mode | INTC_MODE_IS_PRIO;
179 	    *datap = &pr->value;
180 	    *enums = pr->enum_ids;
181 	    *first = (pr->reg_width / pr->field_width) - 1;
182 	    *width = pr->field_width;
183 	    return;
184 	}
185     }
186 
187     abort();
188 }
189 
190 static void sh_intc_toggle_mask(struct intc_desc *desc, intc_enum id,
191 				int enable, int is_group)
192 {
193     struct intc_source *source = desc->sources + id;
194 
195     if (!id)
196 	return;
197 
198     if (!source->next_enum_id && (!source->enable_max || !source->vect)) {
199 #ifdef DEBUG_INTC_SOURCES
200         printf("sh_intc: reserved interrupt source %d modified\n", id);
201 #endif
202 	return;
203     }
204 
205     if (source->vect)
206         sh_intc_toggle_source(source, enable ? 1 : -1, 0);
207 
208 #ifdef DEBUG_INTC
209     else {
210         printf("setting interrupt group %d to %d\n", id, !!enable);
211     }
212 #endif
213 
214     if ((is_group || !source->vect) && source->next_enum_id) {
215         sh_intc_toggle_mask(desc, source->next_enum_id, enable, 1);
216     }
217 
218 #ifdef DEBUG_INTC
219     if (!source->vect) {
220         printf("setting interrupt group %d to %d - done\n", id, !!enable);
221     }
222 #endif
223 }
224 
225 static uint64_t sh_intc_read(void *opaque, hwaddr offset,
226                              unsigned size)
227 {
228     struct intc_desc *desc = opaque;
229     intc_enum *enum_ids = NULL;
230     unsigned int first = 0;
231     unsigned int width = 0;
232     unsigned int mode = 0;
233     unsigned long *valuep;
234 
235 #ifdef DEBUG_INTC
236     printf("sh_intc_read 0x%lx\n", (unsigned long) offset);
237 #endif
238 
239     sh_intc_locate(desc, (unsigned long)offset, &valuep,
240 		   &enum_ids, &first, &width, &mode);
241     return *valuep;
242 }
243 
244 static void sh_intc_write(void *opaque, hwaddr offset,
245                           uint64_t value, unsigned size)
246 {
247     struct intc_desc *desc = opaque;
248     intc_enum *enum_ids = NULL;
249     unsigned int first = 0;
250     unsigned int width = 0;
251     unsigned int mode = 0;
252     unsigned int k;
253     unsigned long *valuep;
254     unsigned long mask;
255 
256 #ifdef DEBUG_INTC
257     printf("sh_intc_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
258 #endif
259 
260     sh_intc_locate(desc, (unsigned long)offset, &valuep,
261 		   &enum_ids, &first, &width, &mode);
262 
263     switch (mode) {
264     case INTC_MODE_ENABLE_REG | INTC_MODE_IS_PRIO: break;
265     case INTC_MODE_DUAL_SET: value |= *valuep; break;
266     case INTC_MODE_DUAL_CLR: value = *valuep & ~value; break;
267     default: abort();
268     }
269 
270     for (k = 0; k <= first; k++) {
271         mask = ((1 << width) - 1) << ((first - k) * width);
272 
273 	if ((*valuep & mask) == (value & mask))
274             continue;
275 #if 0
276 	printf("k = %d, first = %d, enum = %d, mask = 0x%08x\n",
277 	       k, first, enum_ids[k], (unsigned int)mask);
278 #endif
279         sh_intc_toggle_mask(desc, enum_ids[k], value & mask, 0);
280     }
281 
282     *valuep = value;
283 
284 #ifdef DEBUG_INTC
285     printf("sh_intc_write 0x%lx -> 0x%08x\n", (unsigned long) offset, value);
286 #endif
287 }
288 
289 static const MemoryRegionOps sh_intc_ops = {
290     .read = sh_intc_read,
291     .write = sh_intc_write,
292     .endianness = DEVICE_NATIVE_ENDIAN,
293 };
294 
295 struct intc_source *sh_intc_source(struct intc_desc *desc, intc_enum id)
296 {
297     if (id)
298         return desc->sources + id;
299 
300     return NULL;
301 }
302 
303 static unsigned int sh_intc_register(MemoryRegion *sysmem,
304                              struct intc_desc *desc,
305                              const unsigned long address,
306                              const char *type,
307                              const char *action,
308                              const unsigned int index)
309 {
310     char name[60];
311     MemoryRegion *iomem, *iomem_p4, *iomem_a7;
312 
313     if (!address) {
314         return 0;
315     }
316 
317     iomem = &desc->iomem;
318     iomem_p4 = desc->iomem_aliases + index;
319     iomem_a7 = iomem_p4 + 1;
320 
321 #define SH_INTC_IOMEM_FORMAT "interrupt-controller-%s-%s-%s"
322     snprintf(name, sizeof(name), SH_INTC_IOMEM_FORMAT, type, action, "p4");
323     memory_region_init_alias(iomem_p4, NULL, name, iomem, INTC_A7(address), 4);
324     memory_region_add_subregion(sysmem, P4ADDR(address), iomem_p4);
325 
326     snprintf(name, sizeof(name), SH_INTC_IOMEM_FORMAT, type, action, "a7");
327     memory_region_init_alias(iomem_a7, NULL, name, iomem, INTC_A7(address), 4);
328     memory_region_add_subregion(sysmem, A7ADDR(address), iomem_a7);
329 #undef SH_INTC_IOMEM_FORMAT
330 
331     /* used to increment aliases index */
332     return 2;
333 }
334 
335 static void sh_intc_register_source(struct intc_desc *desc,
336 				    intc_enum source,
337 				    struct intc_group *groups,
338 				    int nr_groups)
339 {
340     unsigned int i, k;
341     struct intc_source *s;
342 
343     if (desc->mask_regs) {
344         for (i = 0; i < desc->nr_mask_regs; i++) {
345 	    struct intc_mask_reg *mr = desc->mask_regs + i;
346 
347 	    for (k = 0; k < ARRAY_SIZE(mr->enum_ids); k++) {
348                 if (mr->enum_ids[k] != source)
349                     continue;
350 
351 		s = sh_intc_source(desc, mr->enum_ids[k]);
352 		if (s)
353                     s->enable_max++;
354 	    }
355 	}
356     }
357 
358     if (desc->prio_regs) {
359         for (i = 0; i < desc->nr_prio_regs; i++) {
360 	    struct intc_prio_reg *pr = desc->prio_regs + i;
361 
362 	    for (k = 0; k < ARRAY_SIZE(pr->enum_ids); k++) {
363                 if (pr->enum_ids[k] != source)
364                     continue;
365 
366 		s = sh_intc_source(desc, pr->enum_ids[k]);
367 		if (s)
368                     s->enable_max++;
369 	    }
370 	}
371     }
372 
373     if (groups) {
374         for (i = 0; i < nr_groups; i++) {
375 	    struct intc_group *gr = groups + i;
376 
377 	    for (k = 0; k < ARRAY_SIZE(gr->enum_ids); k++) {
378                 if (gr->enum_ids[k] != source)
379                     continue;
380 
381 		s = sh_intc_source(desc, gr->enum_ids[k]);
382 		if (s)
383                     s->enable_max++;
384 	    }
385 	}
386     }
387 
388 }
389 
390 void sh_intc_register_sources(struct intc_desc *desc,
391 			      struct intc_vect *vectors,
392 			      int nr_vectors,
393 			      struct intc_group *groups,
394 			      int nr_groups)
395 {
396     unsigned int i, k;
397     struct intc_source *s;
398 
399     for (i = 0; i < nr_vectors; i++) {
400 	struct intc_vect *vect = vectors + i;
401 
402 	sh_intc_register_source(desc, vect->enum_id, groups, nr_groups);
403 	s = sh_intc_source(desc, vect->enum_id);
404         if (s) {
405             s->vect = vect->vect;
406 
407 #ifdef DEBUG_INTC_SOURCES
408             printf("sh_intc: registered source %d -> 0x%04x (%d/%d)\n",
409                    vect->enum_id, s->vect, s->enable_count, s->enable_max);
410 #endif
411         }
412     }
413 
414     if (groups) {
415         for (i = 0; i < nr_groups; i++) {
416 	    struct intc_group *gr = groups + i;
417 
418 	    s = sh_intc_source(desc, gr->enum_id);
419 	    s->next_enum_id = gr->enum_ids[0];
420 
421 	    for (k = 1; k < ARRAY_SIZE(gr->enum_ids); k++) {
422                 if (!gr->enum_ids[k])
423                     continue;
424 
425 		s = sh_intc_source(desc, gr->enum_ids[k - 1]);
426 		s->next_enum_id = gr->enum_ids[k];
427 	    }
428 
429 #ifdef DEBUG_INTC_SOURCES
430 	    printf("sh_intc: registered group %d (%d/%d)\n",
431 		   gr->enum_id, s->enable_count, s->enable_max);
432 #endif
433 	}
434     }
435 }
436 
437 int sh_intc_init(MemoryRegion *sysmem,
438          struct intc_desc *desc,
439 		 int nr_sources,
440 		 struct intc_mask_reg *mask_regs,
441 		 int nr_mask_regs,
442 		 struct intc_prio_reg *prio_regs,
443 		 int nr_prio_regs)
444 {
445     unsigned int i, j;
446 
447     desc->pending = 0;
448     desc->nr_sources = nr_sources;
449     desc->mask_regs = mask_regs;
450     desc->nr_mask_regs = nr_mask_regs;
451     desc->prio_regs = prio_regs;
452     desc->nr_prio_regs = nr_prio_regs;
453     /* Allocate 4 MemoryRegions per register (2 actions * 2 aliases).
454      **/
455     desc->iomem_aliases = g_new0(MemoryRegion,
456                                  (nr_mask_regs + nr_prio_regs) * 4);
457 
458     j = 0;
459     i = sizeof(struct intc_source) * nr_sources;
460     desc->sources = g_malloc0(i);
461 
462     for (i = 0; i < desc->nr_sources; i++) {
463         struct intc_source *source = desc->sources + i;
464 
465         source->parent = desc;
466     }
467 
468     desc->irqs = qemu_allocate_irqs(sh_intc_set_irq, desc, nr_sources);
469 
470     memory_region_init_io(&desc->iomem, NULL, &sh_intc_ops, desc,
471                           "interrupt-controller", 0x100000000ULL);
472 
473 #define INT_REG_PARAMS(reg_struct, type, action, j) \
474         reg_struct->action##_reg, #type, #action, j
475     if (desc->mask_regs) {
476         for (i = 0; i < desc->nr_mask_regs; i++) {
477 	    struct intc_mask_reg *mr = desc->mask_regs + i;
478 
479             j += sh_intc_register(sysmem, desc,
480                                   INT_REG_PARAMS(mr, mask, set, j));
481             j += sh_intc_register(sysmem, desc,
482                                   INT_REG_PARAMS(mr, mask, clr, j));
483 	}
484     }
485 
486     if (desc->prio_regs) {
487         for (i = 0; i < desc->nr_prio_regs; i++) {
488 	    struct intc_prio_reg *pr = desc->prio_regs + i;
489 
490             j += sh_intc_register(sysmem, desc,
491                                   INT_REG_PARAMS(pr, prio, set, j));
492             j += sh_intc_register(sysmem, desc,
493                                   INT_REG_PARAMS(pr, prio, clr, j));
494 	}
495     }
496 #undef INT_REG_PARAMS
497 
498     return 0;
499 }
500 
501 /* Assert level <n> IRL interrupt.
502    0:deassert. 1:lowest priority,... 15:highest priority. */
503 void sh_intc_set_irl(void *opaque, int n, int level)
504 {
505     struct intc_source *s = opaque;
506     int i, irl = level ^ 15;
507     for (i = 0; (s = sh_intc_source(s->parent, s->next_enum_id)); i++) {
508 	if (i == irl)
509 	    sh_intc_toggle_source(s, s->enable_count?0:1, s->asserted?0:1);
510 	else
511 	    if (s->asserted)
512 	        sh_intc_toggle_source(s, 0, -1);
513     }
514 }
515