hw/sh_intc.c

   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 licenced under the GPL.
   9  */
  10
  11 #include <assert.h>
  12 #include "sh_intc.h"
  13 #include "hw.h"
  14 #include "sh.h"
  15
  16 //#define DEBUG_INTC
  17 //#define DEBUG_INTC_SOURCES
  18
  19 #define INTC_A7(x) ((x) & 0x1fffffff)
  20 #define INTC_ARRAY(x) (sizeof(x) / sizeof(x[0]))
  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   if (enable_changed || assert_adj || pending_changed) {
  60 #ifdef DEBUG_INTC_SOURCES
  61             printf("sh_intc: (%d/%d/%d/%d) interrupt source 0x%x %s%s%s\n",
  62                    source->parent->pending,
  63                    source->asserted,
  64                    source->enable_count,
  65                    source->enable_max,
  66                    source->vect,
  67                    source->asserted ? "asserted " :
  68                    assert_adj ? "deasserted" : "",
  69                    enable_changed == 1 ? "enabled " :
  70                    enable_changed == -1 ? "disabled " : "",
  71                    source->pending ? "pending" : "");
  72 #endif
  73   }
  74 }
  75
  76 int sh_intc_get_pending_vector(struct intc_desc *desc, int imask)
  77 {
  78     unsigned int i;
  79
  80     /* slow: use a linked lists of pending sources instead */
  81     /* wrong: take interrupt priority into account (one list per priority) */
  82
  83     if (imask == 0x0f) {
  84         return -1; /* FIXME, update code to include priority per source */
  85     }
  86
  87     for (i = 0; i < desc->nr_sources; i++) {
  88         struct intc_source *source = desc->sources + i;
  89
  90         if (source->pending) {
  91 #ifdef DEBUG_INTC_SOURCES
  92             printf("sh_intc: (%d) returning interrupt source 0x%x\n",
  93                    desc->pending, source->vect);
  94 #endif
  95             return source->vect;
  96         }
  97     }
  98
  99     assert(0);
 100 }
 101
 102 #define INTC_MODE_NONE       0
 103 #define INTC_MODE_DUAL_SET   1
 104 #define INTC_MODE_DUAL_CLR   2
 105 #define INTC_MODE_ENABLE_REG 3
 106 #define INTC_MODE_MASK_REG   4
 107 #define INTC_MODE_IS_PRIO    8
 108
 109 static unsigned int sh_intc_mode(unsigned long address,
 110                                  unsigned long set_reg, unsigned long clr_reg)
 111 {
 112     if ((address != INTC_A7(set_reg)) &&
 113         (address != INTC_A7(clr_reg)))
 114         return INTC_MODE_NONE;
 115
 116     if (set_reg && clr_reg) {
 117         if (address == INTC_A7(set_reg))
 118             return INTC_MODE_DUAL_SET;
 119         else
 120             return INTC_MODE_DUAL_CLR;
 121     }
 122
 123     if (set_reg)
 124         return INTC_MODE_ENABLE_REG;
 125     else
 126         return INTC_MODE_MASK_REG;
 127 }
 128
 129 static void sh_intc_locate(struct intc_desc *desc,
 130                            unsigned long address,
 131                            unsigned long **datap,
 132                            intc_enum **enums,
 133                            unsigned int *first,
 134                            unsigned int *width,
 135                            unsigned int *modep)
 136 {
 137     unsigned int i, mode;
 138
 139     /* this is slow but works for now */
 140
 141     if (desc->mask_regs) {
 142         for (i = 0; i < desc->nr_mask_regs; i++) {
 143             struct intc_mask_reg *mr = desc->mask_regs + i;
 144
 145             mode = sh_intc_mode(address, mr->set_reg, mr->clr_reg);
 146             if (mode == INTC_MODE_NONE)
 147                 continue;
 148
 149             *modep = mode;
 150             *datap = &mr->value;
 151             *enums = mr->enum_ids;
 152             *first = mr->reg_width - 1;
 153             *width = 1;
 154             return;
 155         }
 156     }
 157
 158     if (desc->prio_regs) {
 159         for (i = 0; i < desc->nr_prio_regs; i++) {
 160             struct intc_prio_reg *pr = desc->prio_regs + i;
 161
 162             mode = sh_intc_mode(address, pr->set_reg, pr->clr_reg);
 163             if (mode == INTC_MODE_NONE)
 164                 continue;
 165
 166             *modep = mode | INTC_MODE_IS_PRIO;
 167             *datap = &pr->value;
 168             *enums = pr->enum_ids;
 169             *first = (pr->reg_width / pr->field_width) - 1;
 170             *width = pr->field_width;
 171             return;
 172         }
 173     }
 174
 175     assert(0);
 176 }
 177
 178 static void sh_intc_toggle_mask(struct intc_desc *desc, intc_enum id,
 179                                 int enable, int is_group)
 180 {
 181     struct intc_source *source = desc->sources + id;
 182
 183     if (!id)
 184         return;
 185
 186     if (!source->next_enum_id && (!source->enable_max || !source->vect)) {
 187 #ifdef DEBUG_INTC_SOURCES
 188         printf("sh_intc: reserved interrupt source %d modified\n", id);
 189 #endif
 190         return;
 191     }
 192
 193     if (source->vect)
 194         sh_intc_toggle_source(source, enable ? 1 : -1, 0);
 195
 196 #ifdef DEBUG_INTC
 197     else {
 198         printf("setting interrupt group %d to %d\n", id, !!enable);
 199     }
 200 #endif
 201
 202     if ((is_group || !source->vect) && source->next_enum_id) {
 203         sh_intc_toggle_mask(desc, source->next_enum_id, enable, 1);
 204     }
 205
 206 #ifdef DEBUG_INTC
 207     if (!source->vect) {
 208         printf("setting interrupt group %d to %d - done\n", id, !!enable);
 209     }
 210 #endif
 211 }
 212
 213 static uint32_t sh_intc_read(void *opaque, target_phys_addr_t offset)
 214 {
 215     struct intc_desc *desc = opaque;
 216     intc_enum *enum_ids = NULL;
 217     unsigned int first = 0;
 218     unsigned int width = 0;
 219     unsigned int mode = 0;
 220     unsigned long *valuep;
 221
 222 #ifdef DEBUG_INTC
 223     printf("sh_intc_read 0x%lx\n", (unsigned long) offset);
 224 #endif
 225
 226     sh_intc_locate(desc, (unsigned long)offset, &valuep,
 227                    &enum_ids, &first, &width, &mode);
 228     return *valuep;
 229 }
 230
 231 static void sh_intc_write(void *opaque, target_phys_addr_t offset,
 232                           uint32_t value)
 233 {
 234     struct intc_desc *desc = opaque;
 235     intc_enum *enum_ids = NULL;
 236     unsigned int first = 0;
 237     unsigned int width = 0;
 238     unsigned int mode = 0;
 239     unsigned int k;
 240     unsigned long *valuep;
 241     unsigned long mask;
 242
 243 #ifdef DEBUG_INTC
 244     printf("sh_intc_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
 245 #endif
 246
 247     sh_intc_locate(desc, (unsigned long)offset, &valuep,
 248                    &enum_ids, &first, &width, &mode);
 249
 250     switch (mode) {
 251     case INTC_MODE_ENABLE_REG | INTC_MODE_IS_PRIO: break;
 252     case INTC_MODE_DUAL_SET: value |= *valuep; break;
 253     case INTC_MODE_DUAL_CLR: value = *valuep & ~value; break;
 254     default: assert(0);
 255     }
 256
 257     for (k = 0; k <= first; k++) {
 258         mask = ((1 << width) - 1) << ((first - k) * width);
 259
 260         if ((*valuep & mask) == (value & mask))
 261             continue;
 262 #if 0
 263         printf("k = %d, first = %d, enum = %d, mask = 0x%08x\n",
 264                k, first, enum_ids[k], (unsigned int)mask);
 265 #endif
 266         sh_intc_toggle_mask(desc, enum_ids[k], value & mask, 0);
 267     }
 268
 269     *valuep = value;
 270
 271 #ifdef DEBUG_INTC
 272     printf("sh_intc_write 0x%lx -> 0x%08x\n", (unsigned long) offset, value);
 273 #endif
 274 }
 275
 276 static CPUReadMemoryFunc *sh_intc_readfn[] = {
 277     sh_intc_read,
 278     sh_intc_read,
 279     sh_intc_read
 280 };
 281
 282 static CPUWriteMemoryFunc *sh_intc_writefn[] = {
 283     sh_intc_write,
 284     sh_intc_write,
 285     sh_intc_write
 286 };
 287
 288 struct intc_source *sh_intc_source(struct intc_desc *desc, intc_enum id)
 289 {
 290     if (id)
 291         return desc->sources + id;
 292
 293     return NULL;
 294 }
 295
 296 static void sh_intc_register(struct intc_desc *desc,
 297                              unsigned long address)
 298 {
 299     if (address)
 300         cpu_register_physical_memory(INTC_A7(address), 4, desc->iomemtype);
 301 }
 302
 303 static void sh_intc_register_source(struct intc_desc *desc,
 304                                     intc_enum source,
 305                                     struct intc_group *groups,
 306                                     int nr_groups)
 307 {
 308     unsigned int i, k;
 309     struct intc_source *s;
 310
 311     if (desc->mask_regs) {
 312         for (i = 0; i < desc->nr_mask_regs; i++) {
 313             struct intc_mask_reg *mr = desc->mask_regs + i;
 314
 315             for (k = 0; k < INTC_ARRAY(mr->enum_ids); k++) {
 316                 if (mr->enum_ids[k] != source)
 317                     continue;
 318
 319                 s = sh_intc_source(desc, mr->enum_ids[k]);
 320                 if (s)
 321                     s->enable_max++;
 322             }
 323         }
 324     }
 325
 326     if (desc->prio_regs) {
 327         for (i = 0; i < desc->nr_prio_regs; i++) {
 328             struct intc_prio_reg *pr = desc->prio_regs + i;
 329
 330             for (k = 0; k < INTC_ARRAY(pr->enum_ids); k++) {
 331                 if (pr->enum_ids[k] != source)
 332                     continue;
 333
 334                 s = sh_intc_source(desc, pr->enum_ids[k]);
 335                 if (s)
 336                     s->enable_max++;
 337             }
 338         }
 339     }
 340
 341     if (groups) {
 342         for (i = 0; i < nr_groups; i++) {
 343             struct intc_group *gr = groups + i;
 344
 345             for (k = 0; k < INTC_ARRAY(gr->enum_ids); k++) {
 346                 if (gr->enum_ids[k] != source)
 347                     continue;
 348
 349                 s = sh_intc_source(desc, gr->enum_ids[k]);
 350                 if (s)
 351                     s->enable_max++;
 352             }
 353         }
 354     }
 355
 356 }
 357
 358 void sh_intc_register_sources(struct intc_desc *desc,
 359                               struct intc_vect *vectors,
 360                               int nr_vectors,
 361                               struct intc_group *groups,
 362                               int nr_groups)
 363 {
 364     unsigned int i, k;
 365     struct intc_source *s;
 366
 367     for (i = 0; i < nr_vectors; i++) {
 368         struct intc_vect *vect = vectors + i;
 369
 370         sh_intc_register_source(desc, vect->enum_id, groups, nr_groups);
 371         s = sh_intc_source(desc, vect->enum_id);
 372         if (s)
 373             s->vect = vect->vect;
 374
 375 #ifdef DEBUG_INTC_SOURCES
 376         printf("sh_intc: registered source %d -> 0x%04x (%d/%d)\n",
 377                vect->enum_id, s->vect, s->enable_count, s->enable_max);
 378 #endif
 379     }
 380
 381     if (groups) {
 382         for (i = 0; i < nr_groups; i++) {
 383             struct intc_group *gr = groups + i;
 384
 385             s = sh_intc_source(desc, gr->enum_id);
 386             s->next_enum_id = gr->enum_ids[0];
 387
 388             for (k = 1; k < INTC_ARRAY(gr->enum_ids); k++) {
 389                 if (!gr->enum_ids[k])
 390                     continue;
 391
 392                 s = sh_intc_source(desc, gr->enum_ids[k - 1]);
 393                 s->next_enum_id = gr->enum_ids[k];
 394             }
 395
 396 #ifdef DEBUG_INTC_SOURCES
 397             printf("sh_intc: registered group %d (%d/%d)\n",
 398                    gr->enum_id, s->enable_count, s->enable_max);
 399 #endif
 400         }
 401     }
 402 }
 403
 404 int sh_intc_init(struct intc_desc *desc,
 405                  int nr_sources,
 406                  struct intc_mask_reg *mask_regs,
 407                  int nr_mask_regs,
 408                  struct intc_prio_reg *prio_regs,
 409                  int nr_prio_regs)
 410 {
 411     unsigned int i;
 412
 413     desc->pending = 0;
 414     desc->nr_sources = nr_sources;
 415     desc->mask_regs = mask_regs;
 416     desc->nr_mask_regs = nr_mask_regs;
 417     desc->prio_regs = prio_regs;
 418     desc->nr_prio_regs = nr_prio_regs;
 419
 420     i = sizeof(struct intc_source) * nr_sources;
 421     desc->sources = malloc(i);
 422     if (!desc->sources)
 423         return -1;
 424
 425     memset(desc->sources, 0, i);
 426     for (i = 0; i < desc->nr_sources; i++) {
 427         struct intc_source *source = desc->sources + i;
 428
 429         source->parent = desc;
 430     }
 431
 432     desc->iomemtype = cpu_register_io_memory(0, sh_intc_readfn,
 433                                              sh_intc_writefn, desc);
 434     if (desc->mask_regs) {
 435         for (i = 0; i < desc->nr_mask_regs; i++) {
 436             struct intc_mask_reg *mr = desc->mask_regs + i;
 437
 438             sh_intc_register(desc, mr->set_reg);
 439             sh_intc_register(desc, mr->clr_reg);
 440         }
 441     }
 442
 443     if (desc->prio_regs) {
 444         for (i = 0; i < desc->nr_prio_regs; i++) {
 445             struct intc_prio_reg *pr = desc->prio_regs + i;
 446
 447             sh_intc_register(desc, pr->set_reg);
 448             sh_intc_register(desc, pr->clr_reg);
 449         }
 450     }
 451
 452     return 0;
 453 }