xref: /openbmc/qemu/hw/intc/sh_intc.c (revision 97a5b35c)
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 "qemu/log.h"
13 #include "cpu.h"
14 #include "hw/sh4/sh_intc.h"
15 #include "hw/irq.h"
16 #include "hw/sh4/sh.h"
17 #include "trace.h"
18 
19 void sh_intc_toggle_source(struct intc_source *source,
20                            int enable_adj, int assert_adj)
21 {
22     int enable_changed = 0;
23     int pending_changed = 0;
24     int old_pending;
25 
26     if (source->enable_count == source->enable_max && enable_adj == -1) {
27         enable_changed = -1;
28     }
29     source->enable_count += enable_adj;
30 
31     if (source->enable_count == source->enable_max) {
32         enable_changed = 1;
33     }
34     source->asserted += assert_adj;
35 
36     old_pending = source->pending;
37     source->pending = source->asserted &&
38       (source->enable_count == source->enable_max);
39 
40     if (old_pending != source->pending) {
41         pending_changed = 1;
42     }
43     if (pending_changed) {
44         if (source->pending) {
45             source->parent->pending++;
46             if (source->parent->pending == 1) {
47                 cpu_interrupt(first_cpu, CPU_INTERRUPT_HARD);
48             }
49         } else {
50             source->parent->pending--;
51             if (source->parent->pending == 0) {
52                 cpu_reset_interrupt(first_cpu, CPU_INTERRUPT_HARD);
53             }
54         }
55     }
56 
57     if (enable_changed || assert_adj || pending_changed) {
58         trace_sh_intc_sources(source->parent->pending, source->asserted,
59                               source->enable_count, source->enable_max,
60                               source->vect, source->asserted ? "asserted " :
61                               assert_adj ? "deasserted" : "",
62                               enable_changed == 1 ? "enabled " :
63                               enable_changed == -1 ? "disabled " : "",
64                               source->pending ? "pending" : "");
65     }
66 }
67 
68 static void sh_intc_set_irq(void *opaque, int n, int level)
69 {
70     struct intc_desc *desc = opaque;
71     struct intc_source *source = &desc->sources[n];
72 
73     if (level && !source->asserted) {
74         sh_intc_toggle_source(source, 0, 1);
75     } else if (!level && source->asserted) {
76         sh_intc_toggle_source(source, 0, -1);
77     }
78 }
79 
80 int sh_intc_get_pending_vector(struct intc_desc *desc, int imask)
81 {
82     unsigned int i;
83 
84     /* slow: use a linked lists of pending sources instead */
85     /* wrong: take interrupt priority into account (one list per priority) */
86 
87     if (imask == 0x0f) {
88         return -1; /* FIXME, update code to include priority per source */
89     }
90 
91     for (i = 0; i < desc->nr_sources; i++) {
92         struct intc_source *source = &desc->sources[i];
93 
94         if (source->pending) {
95             trace_sh_intc_pending(desc->pending, source->vect);
96             return source->vect;
97         }
98     }
99     g_assert_not_reached();
100 }
101 
102 typedef enum {
103     INTC_MODE_NONE,
104     INTC_MODE_DUAL_SET,
105     INTC_MODE_DUAL_CLR,
106     INTC_MODE_ENABLE_REG,
107     INTC_MODE_MASK_REG,
108 } SHIntCMode;
109 #define INTC_MODE_IS_PRIO 0x80
110 
111 static SHIntCMode sh_intc_mode(unsigned long address, unsigned long set_reg,
112                                unsigned long clr_reg)
113 {
114     if (address != A7ADDR(set_reg) && address != A7ADDR(clr_reg)) {
115         return INTC_MODE_NONE;
116     }
117     if (set_reg && clr_reg) {
118         return address == A7ADDR(set_reg) ?
119                INTC_MODE_DUAL_SET : INTC_MODE_DUAL_CLR;
120     }
121     return set_reg ? INTC_MODE_ENABLE_REG : INTC_MODE_MASK_REG;
122 }
123 
124 static void sh_intc_locate(struct intc_desc *desc,
125                            unsigned long address,
126                            unsigned long **datap,
127                            intc_enum **enums,
128                            unsigned int *first,
129                            unsigned int *width,
130                            unsigned int *modep)
131 {
132     SHIntCMode mode;
133     unsigned int i;
134 
135     /* this is slow but works for now */
136 
137     if (desc->mask_regs) {
138         for (i = 0; i < desc->nr_mask_regs; i++) {
139             struct intc_mask_reg *mr = &desc->mask_regs[i];
140 
141             mode = sh_intc_mode(address, mr->set_reg, mr->clr_reg);
142             if (mode != INTC_MODE_NONE) {
143                 *modep = mode;
144                 *datap = &mr->value;
145                 *enums = mr->enum_ids;
146                 *first = mr->reg_width - 1;
147                 *width = 1;
148                 return;
149             }
150         }
151     }
152 
153     if (desc->prio_regs) {
154         for (i = 0; i < desc->nr_prio_regs; i++) {
155             struct intc_prio_reg *pr = &desc->prio_regs[i];
156 
157             mode = sh_intc_mode(address, pr->set_reg, pr->clr_reg);
158             if (mode != INTC_MODE_NONE) {
159                 *modep = mode | INTC_MODE_IS_PRIO;
160                 *datap = &pr->value;
161                 *enums = pr->enum_ids;
162                 *first = pr->reg_width / pr->field_width - 1;
163                 *width = pr->field_width;
164                 return;
165             }
166         }
167     }
168     g_assert_not_reached();
169 }
170 
171 static void sh_intc_toggle_mask(struct intc_desc *desc, intc_enum id,
172                                 int enable, int is_group)
173 {
174     struct intc_source *source = &desc->sources[id];
175 
176     if (!id) {
177         return;
178     }
179     if (!source->next_enum_id && (!source->enable_max || !source->vect)) {
180         qemu_log_mask(LOG_UNIMP,
181                       "sh_intc: reserved interrupt source %d modified\n", id);
182         return;
183     }
184 
185     if (source->vect) {
186         sh_intc_toggle_source(source, enable ? 1 : -1, 0);
187     }
188 
189     if ((is_group || !source->vect) && source->next_enum_id) {
190         sh_intc_toggle_mask(desc, source->next_enum_id, enable, 1);
191     }
192 
193     if (!source->vect) {
194         trace_sh_intc_set(id, !!enable);
195     }
196 }
197 
198 static uint64_t sh_intc_read(void *opaque, hwaddr offset, unsigned size)
199 {
200     struct intc_desc *desc = opaque;
201     intc_enum *enum_ids;
202     unsigned int first;
203     unsigned int width;
204     unsigned int mode;
205     unsigned long *valuep;
206 
207     sh_intc_locate(desc, (unsigned long)offset, &valuep,
208                    &enum_ids, &first, &width, &mode);
209     trace_sh_intc_read(size, (uint64_t)offset, *valuep);
210     return *valuep;
211 }
212 
213 static void sh_intc_write(void *opaque, hwaddr offset,
214                           uint64_t value, unsigned size)
215 {
216     struct intc_desc *desc = opaque;
217     intc_enum *enum_ids;
218     unsigned int first;
219     unsigned int width;
220     unsigned int mode;
221     unsigned long *valuep;
222     unsigned int k;
223     unsigned long mask;
224 
225     trace_sh_intc_write(size, (uint64_t)offset, value);
226     sh_intc_locate(desc, (unsigned long)offset, &valuep,
227                    &enum_ids, &first, &width, &mode);
228     switch (mode) {
229     case INTC_MODE_ENABLE_REG | INTC_MODE_IS_PRIO:
230         break;
231     case INTC_MODE_DUAL_SET:
232         value |= *valuep;
233         break;
234     case INTC_MODE_DUAL_CLR:
235         value = *valuep & ~value;
236         break;
237     default:
238         g_assert_not_reached();
239     }
240 
241     for (k = 0; k <= first; k++) {
242         mask = (1 << width) - 1;
243         mask <<= (first - k) * width;
244 
245         if ((*valuep & mask) != (value & mask)) {
246             sh_intc_toggle_mask(desc, enum_ids[k], value & mask, 0);
247         }
248     }
249 
250     *valuep = value;
251 }
252 
253 static const MemoryRegionOps sh_intc_ops = {
254     .read = sh_intc_read,
255     .write = sh_intc_write,
256     .endianness = DEVICE_NATIVE_ENDIAN,
257 };
258 
259 static void sh_intc_register_source(struct intc_desc *desc,
260                                     intc_enum source,
261                                     struct intc_group *groups,
262                                     int nr_groups)
263 {
264     unsigned int i, k;
265     intc_enum id;
266 
267     if (desc->mask_regs) {
268         for (i = 0; i < desc->nr_mask_regs; i++) {
269             struct intc_mask_reg *mr = &desc->mask_regs[i];
270 
271             for (k = 0; k < ARRAY_SIZE(mr->enum_ids); k++) {
272                 id = mr->enum_ids[k];
273                 if (id && id == source) {
274                     desc->sources[id].enable_max++;
275                 }
276             }
277         }
278     }
279 
280     if (desc->prio_regs) {
281         for (i = 0; i < desc->nr_prio_regs; i++) {
282             struct intc_prio_reg *pr = &desc->prio_regs[i];
283 
284             for (k = 0; k < ARRAY_SIZE(pr->enum_ids); k++) {
285                 id = pr->enum_ids[k];
286                 if (id && id == source) {
287                     desc->sources[id].enable_max++;
288                 }
289             }
290         }
291     }
292 
293     if (groups) {
294         for (i = 0; i < nr_groups; i++) {
295             struct intc_group *gr = &groups[i];
296 
297             for (k = 0; k < ARRAY_SIZE(gr->enum_ids); k++) {
298                 id = gr->enum_ids[k];
299                 if (id && id == source) {
300                     desc->sources[id].enable_max++;
301                 }
302             }
303         }
304     }
305 
306 }
307 
308 void sh_intc_register_sources(struct intc_desc *desc,
309                               struct intc_vect *vectors,
310                               int nr_vectors,
311                               struct intc_group *groups,
312                               int nr_groups)
313 {
314     unsigned int i, k;
315     intc_enum id;
316     struct intc_source *s;
317 
318     for (i = 0; i < nr_vectors; i++) {
319         struct intc_vect *vect = &vectors[i];
320 
321         sh_intc_register_source(desc, vect->enum_id, groups, nr_groups);
322         id = vect->enum_id;
323         if (id) {
324             s = &desc->sources[id];
325             s->vect = vect->vect;
326             trace_sh_intc_register("source", vect->enum_id, s->vect,
327                                    s->enable_count, s->enable_max);
328         }
329     }
330 
331     if (groups) {
332         for (i = 0; i < nr_groups; i++) {
333             struct intc_group *gr = &groups[i];
334 
335             id = gr->enum_id;
336             s = &desc->sources[id];
337             s->next_enum_id = gr->enum_ids[0];
338 
339             for (k = 1; k < ARRAY_SIZE(gr->enum_ids); k++) {
340                 if (gr->enum_ids[k]) {
341                     id = gr->enum_ids[k - 1];
342                     s = &desc->sources[id];
343                     s->next_enum_id = gr->enum_ids[k];
344                 }
345             }
346             trace_sh_intc_register("group", gr->enum_id, 0xffff,
347                                    s->enable_count, s->enable_max);
348         }
349     }
350 }
351 
352 static unsigned int sh_intc_register(MemoryRegion *sysmem,
353                                      struct intc_desc *desc,
354                                      const unsigned long address,
355                                      const char *type,
356                                      const char *action,
357                                      const unsigned int index)
358 {
359     char name[60];
360     MemoryRegion *iomem, *iomem_p4, *iomem_a7;
361 
362     if (!address) {
363         return 0;
364     }
365 
366     iomem = &desc->iomem;
367     iomem_p4 = &desc->iomem_aliases[index];
368     iomem_a7 = iomem_p4 + 1;
369 
370     snprintf(name, sizeof(name), "intc-%s-%s-%s", type, action, "p4");
371     memory_region_init_alias(iomem_p4, NULL, name, iomem, A7ADDR(address), 4);
372     memory_region_add_subregion(sysmem, P4ADDR(address), iomem_p4);
373 
374     snprintf(name, sizeof(name), "intc-%s-%s-%s", type, action, "a7");
375     memory_region_init_alias(iomem_a7, NULL, name, iomem, A7ADDR(address), 4);
376     memory_region_add_subregion(sysmem, A7ADDR(address), iomem_a7);
377 
378     /* used to increment aliases index */
379     return 2;
380 }
381 
382 int sh_intc_init(MemoryRegion *sysmem,
383                  struct intc_desc *desc,
384                  int nr_sources,
385                  struct intc_mask_reg *mask_regs,
386                  int nr_mask_regs,
387                  struct intc_prio_reg *prio_regs,
388                  int nr_prio_regs)
389 {
390     unsigned int i, j;
391 
392     desc->pending = 0;
393     desc->nr_sources = nr_sources;
394     desc->mask_regs = mask_regs;
395     desc->nr_mask_regs = nr_mask_regs;
396     desc->prio_regs = prio_regs;
397     desc->nr_prio_regs = nr_prio_regs;
398     /* Allocate 4 MemoryRegions per register (2 actions * 2 aliases) */
399     desc->iomem_aliases = g_new0(MemoryRegion,
400                                  (nr_mask_regs + nr_prio_regs) * 4);
401     desc->sources = g_new0(struct intc_source, nr_sources);
402     for (i = 0; i < nr_sources; i++) {
403         desc->sources[i].parent = desc;
404     }
405     desc->irqs = qemu_allocate_irqs(sh_intc_set_irq, desc, nr_sources);
406     memory_region_init_io(&desc->iomem, NULL, &sh_intc_ops, desc, "intc",
407                           0x100000000ULL);
408     j = 0;
409     if (desc->mask_regs) {
410         for (i = 0; i < desc->nr_mask_regs; i++) {
411             struct intc_mask_reg *mr = &desc->mask_regs[i];
412 
413             j += sh_intc_register(sysmem, desc, mr->set_reg, "mask", "set", j);
414             j += sh_intc_register(sysmem, desc, mr->clr_reg, "mask", "clr", j);
415         }
416     }
417 
418     if (desc->prio_regs) {
419         for (i = 0; i < desc->nr_prio_regs; i++) {
420             struct intc_prio_reg *pr = &desc->prio_regs[i];
421 
422             j += sh_intc_register(sysmem, desc, pr->set_reg, "prio", "set", j);
423             j += sh_intc_register(sysmem, desc, pr->clr_reg, "prio", "clr", j);
424         }
425     }
426 
427     return 0;
428 }
429 
430 /*
431  * Assert level <n> IRL interrupt.
432  * 0:deassert. 1:lowest priority,... 15:highest priority
433  */
434 void sh_intc_set_irl(void *opaque, int n, int level)
435 {
436     struct intc_source *s = opaque;
437     int i, irl = level ^ 15;
438     intc_enum id = s->next_enum_id;
439 
440     for (i = 0; id; id = s->next_enum_id, i++) {
441         s = &s->parent->sources[id];
442         if (i == irl) {
443             sh_intc_toggle_source(s, s->enable_count ? 0 : 1,
444                                   s->asserted ? 0 : 1);
445         } else if (s->asserted) {
446             sh_intc_toggle_source(s, 0, -1);
447         }
448     }
449 }
450