arch/m68k/kernel/ints.c

   1 /*
   2  * linux/arch/m68k/kernel/ints.c -- Linux/m68k general interrupt handling code
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file COPYING in the main directory of this archive
   6  * for more details.
   7  *
   8  * 07/03/96: Timer initialization, and thus mach_sched_init(),
   9  *           removed from request_irq() and moved to init_time().
  10  *           We should therefore consider renaming our add_isr() and
  11  *           remove_isr() to request_irq() and free_irq()
  12  *           respectively, so they are compliant with the other
  13  *           architectures.                                     /Jes
  14  * 11/07/96: Changed all add_/remove_isr() to request_/free_irq() calls.
  15  *           Removed irq list support, if any machine needs an irq server
  16  *           it must implement this itself (as it's already done), instead
  17  *           only default handler are used with mach_default_handler.
  18  *           request_irq got some flags different from other architectures:
  19  *           - IRQ_FLG_REPLACE : Replace an existing handler (the default one
  20  *                               can be replaced without this flag)
  21  *           - IRQ_FLG_LOCK : handler can't be replaced
  22  *           There are other machine depending flags, see there
  23  *           If you want to replace a default handler you should know what
  24  *           you're doing, since it might handle different other irq sources
  25  *           which must be served                               /Roman Zippel
  26  */
  27
  28 #include <linux/module.h>
  29 #include <linux/types.h>
  30 #include <linux/sched.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/kernel_stat.h>
  33 #include <linux/errno.h>
  34 #include <linux/init.h>
  35
  36 #include <asm/setup.h>
  37 #include <asm/system.h>
  38 #include <asm/irq.h>
  39 #include <asm/traps.h>
  40 #include <asm/page.h>
  41 #include <asm/machdep.h>
  42 #include <asm/cacheflush.h>
  43 #include <asm/irq_regs.h>
  44
  45 #ifdef CONFIG_Q40
  46 #include <asm/q40ints.h>
  47 #endif
  48
  49 extern u32 auto_irqhandler_fixup[];
  50 extern u32 user_irqhandler_fixup[];
  51 extern u16 user_irqvec_fixup[];
  52
  53 /* table for system interrupt handlers */
  54 static struct irq_data *irq_list[NR_IRQS];
  55 static struct irq_chip *irq_chip[NR_IRQS];
  56 static int irq_depth[NR_IRQS];
  57
  58 static int m68k_first_user_vec;
  59
  60 static struct irq_chip auto_irq_chip = {
  61         .name           = "auto",
  62         .irq_startup    = m68k_irq_startup,
  63         .irq_shutdown   = m68k_irq_shutdown,
  64 };
  65
  66 static struct irq_chip user_irq_chip = {
  67         .name           = "user",
  68         .irq_startup    = m68k_irq_startup,
  69         .irq_shutdown   = m68k_irq_shutdown,
  70 };
  71
  72 #define NUM_IRQ_NODES 100
  73 static struct irq_data nodes[NUM_IRQ_NODES];
  74
  75 /*
  76  * void init_IRQ(void)
  77  *
  78  * Parameters:  None
  79  *
  80  * Returns:     Nothing
  81  *
  82  * This function should be called during kernel startup to initialize
  83  * the IRQ handling routines.
  84  */
  85
  86 void __init init_IRQ(void)
  87 {
  88         int i;
  89
  90         /* assembly irq entry code relies on this... */
  91         if (HARDIRQ_MASK != 0x00ff0000) {
  92                 extern void hardirq_mask_is_broken(void);
  93                 hardirq_mask_is_broken();
  94         }
  95
  96         for (i = IRQ_AUTO_1; i <= IRQ_AUTO_7; i++)
  97                 irq_chip[i] = &auto_irq_chip;
  98
  99         mach_init_IRQ();
 100 }
 101
 102 /**
 103  * m68k_setup_auto_interrupt
 104  * @handler: called from auto vector interrupts
 105  *
 106  * setup the handler to be called from auto vector interrupts instead of the
 107  * standard __m68k_handle_int(), it will be called with irq numbers in the range
 108  * from IRQ_AUTO_1 - IRQ_AUTO_7.
 109  */
 110 void __init m68k_setup_auto_interrupt(void (*handler)(unsigned int, struct pt_regs *))
 111 {
 112         if (handler)
 113                 *auto_irqhandler_fixup = (u32)handler;
 114         flush_icache();
 115 }
 116
 117 /**
 118  * m68k_setup_user_interrupt
 119  * @vec: first user vector interrupt to handle
 120  * @cnt: number of active user vector interrupts
 121  * @handler: called from user vector interrupts
 122  *
 123  * setup user vector interrupts, this includes activating the specified range
 124  * of interrupts, only then these interrupts can be requested (note: this is
 125  * different from auto vector interrupts). An optional handler can be installed
 126  * to be called instead of the default __m68k_handle_int(), it will be called
 127  * with irq numbers starting from IRQ_USER.
 128  */
 129 void __init m68k_setup_user_interrupt(unsigned int vec, unsigned int cnt,
 130                                       void (*handler)(unsigned int, struct pt_regs *))
 131 {
 132         int i;
 133
 134         BUG_ON(IRQ_USER + cnt > NR_IRQS);
 135         m68k_first_user_vec = vec;
 136         for (i = 0; i < cnt; i++)
 137                 irq_chip[IRQ_USER + i] = &user_irq_chip;
 138         *user_irqvec_fixup = vec - IRQ_USER;
 139         if (handler)
 140                 *user_irqhandler_fixup = (u32)handler;
 141         flush_icache();
 142 }
 143
 144 /**
 145  * m68k_setup_irq_chip
 146  * @contr: irq controller which controls specified irq
 147  * @irq: first irq to be managed by the controller
 148  *
 149  * Change the controller for the specified range of irq, which will be used to
 150  * manage these irq. auto/user irq already have a default controller, which can
 151  * be changed as well, but the controller probably should use m68k_irq_startup/
 152  * m68k_irq_shutdown.
 153  */
 154 void m68k_setup_irq_chip(struct irq_chip *contr, unsigned int irq,
 155                                unsigned int cnt)
 156 {
 157         int i;
 158
 159         for (i = 0; i < cnt; i++)
 160                 irq_chip[irq + i] = contr;
 161 }
 162
 163 struct irq_data *new_irq_node(void)
 164 {
 165         struct irq_data *node;
 166         short i;
 167
 168         for (node = nodes, i = NUM_IRQ_NODES-1; i >= 0; node++, i--) {
 169                 if (!node->handler) {
 170                         memset(node, 0, sizeof(*node));
 171                         return node;
 172                 }
 173         }
 174
 175         printk ("new_irq_node: out of nodes\n");
 176         return NULL;
 177 }
 178
 179 int setup_irq(unsigned int irq, struct irq_data *node)
 180 {
 181         struct irq_chip *contr;
 182         struct irq_data **prev;
 183         unsigned long flags;
 184
 185         if (irq >= NR_IRQS || !(contr = irq_chip[irq])) {
 186                 printk("%s: Incorrect IRQ %d from %s\n",
 187                        __func__, irq, node->devname);
 188                 return -ENXIO;
 189         }
 190
 191         local_irq_save(flags);
 192
 193         prev = irq_list + irq;
 194         if (*prev) {
 195                 /* Can't share interrupts unless both agree to */
 196                 if (!((*prev)->flags & node->flags & IRQF_SHARED)) {
 197                         local_irq_restore(flags);
 198                         return -EBUSY;
 199                 }
 200                 while (*prev)
 201                         prev = &(*prev)->next;
 202         }
 203
 204         if (!irq_list[irq]) {
 205                 if (contr->irq_startup)
 206                         contr->irq_startup(node);
 207                 else
 208                         contr->irq_enable(node);
 209         }
 210         node->next = NULL;
 211         *prev = node;
 212
 213         local_irq_restore(flags);
 214
 215         return 0;
 216 }
 217
 218 int request_irq(unsigned int irq,
 219                 irq_handler_t handler,
 220                 unsigned long flags, const char *devname, void *dev_id)
 221 {
 222         struct irq_data *node;
 223         int res;
 224
 225         node = new_irq_node();
 226         if (!node)
 227                 return -ENOMEM;
 228
 229         node->irq     = irq;
 230         node->handler = handler;
 231         node->flags   = flags;
 232         node->dev_id  = dev_id;
 233         node->devname = devname;
 234
 235         res = setup_irq(irq, node);
 236         if (res)
 237                 node->handler = NULL;
 238
 239         return res;
 240 }
 241
 242 EXPORT_SYMBOL(request_irq);
 243
 244 void free_irq(unsigned int irq, void *dev_id)
 245 {
 246         struct irq_chip *contr;
 247         struct irq_data **p, *node;
 248         unsigned long flags;
 249
 250         if (irq >= NR_IRQS || !(contr = irq_chip[irq])) {
 251                 printk("%s: Incorrect IRQ %d\n", __func__, irq);
 252                 return;
 253         }
 254
 255         local_irq_save(flags);
 256
 257         p = irq_list + irq;
 258         while ((node = *p)) {
 259                 if (node->dev_id == dev_id)
 260                         break;
 261                 p = &node->next;
 262         }
 263
 264         if (node) {
 265                 *p = node->next;
 266                 node->handler = NULL;
 267         } else
 268                 printk("%s: Removing probably wrong IRQ %d\n",
 269                        __func__, irq);
 270
 271         if (!irq_list[irq]) {
 272                 if (contr->irq_shutdown)
 273                         contr->irq_shutdown(node);
 274                 else
 275                         contr->irq_disable(node);
 276         }
 277
 278         local_irq_restore(flags);
 279 }
 280
 281 EXPORT_SYMBOL(free_irq);
 282
 283 void enable_irq(unsigned int irq)
 284 {
 285         struct irq_chip *contr;
 286         unsigned long flags;
 287
 288         if (irq >= NR_IRQS || !(contr = irq_chip[irq])) {
 289                 printk("%s: Incorrect IRQ %d\n",
 290                        __func__, irq);
 291                 return;
 292         }
 293
 294         local_irq_save(flags);
 295         if (irq_depth[irq]) {
 296                 if (!--irq_depth[irq]) {
 297                         if (contr->irq_enable)
 298                                 contr->irq_enable(irq_list[irq]);
 299                 }
 300         } else
 301                 WARN_ON(1);
 302         local_irq_restore(flags);
 303 }
 304
 305 EXPORT_SYMBOL(enable_irq);
 306
 307 void disable_irq(unsigned int irq)
 308 {
 309         struct irq_chip *contr;
 310         unsigned long flags;
 311
 312         if (irq >= NR_IRQS || !(contr = irq_chip[irq])) {
 313                 printk("%s: Incorrect IRQ %d\n",
 314                        __func__, irq);
 315                 return;
 316         }
 317
 318         local_irq_save(flags);
 319         if (!irq_depth[irq]++) {
 320                 if (contr->irq_disable)
 321                         contr->irq_disable(irq_list[irq]);
 322         }
 323         local_irq_restore(flags);
 324 }
 325
 326 EXPORT_SYMBOL(disable_irq);
 327
 328 void disable_irq_nosync(unsigned int irq) __attribute__((alias("disable_irq")));
 329
 330 EXPORT_SYMBOL(disable_irq_nosync);
 331
 332 unsigned int m68k_irq_startup_irq(unsigned int irq)
 333 {
 334         if (irq <= IRQ_AUTO_7)
 335                 vectors[VEC_SPUR + irq] = auto_inthandler;
 336         else
 337                 vectors[m68k_first_user_vec + irq - IRQ_USER] = user_inthandler;
 338         return 0;
 339 }
 340
 341 unsigned int m68k_irq_startup(struct irq_data *data)
 342 {
 343         return m68k_irq_startup_irq(data->irq);
 344 }
 345
 346 void m68k_irq_shutdown(struct irq_data *data)
 347 {
 348         unsigned int irq = data->irq;
 349
 350         if (irq <= IRQ_AUTO_7)
 351                 vectors[VEC_SPUR + irq] = bad_inthandler;
 352         else
 353                 vectors[m68k_first_user_vec + irq - IRQ_USER] = bad_inthandler;
 354 }
 355
 356
 357 /*
 358  * Do we need these probe functions on the m68k?
 359  *
 360  *  ... may be useful with ISA devices
 361  */
 362 unsigned long probe_irq_on (void)
 363 {
 364 #ifdef CONFIG_Q40
 365         if (MACH_IS_Q40)
 366                 return q40_probe_irq_on();
 367 #endif
 368         return 0;
 369 }
 370
 371 EXPORT_SYMBOL(probe_irq_on);
 372
 373 int probe_irq_off (unsigned long irqs)
 374 {
 375 #ifdef CONFIG_Q40
 376         if (MACH_IS_Q40)
 377                 return q40_probe_irq_off(irqs);
 378 #endif
 379         return 0;
 380 }
 381
 382 EXPORT_SYMBOL(probe_irq_off);
 383
 384 unsigned int irq_canonicalize(unsigned int irq)
 385 {
 386 #ifdef CONFIG_Q40
 387         if (MACH_IS_Q40 && irq == 11)
 388                 irq = 10;
 389 #endif
 390         return irq;
 391 }
 392
 393 EXPORT_SYMBOL(irq_canonicalize);
 394
 395 asmlinkage void m68k_handle_int(unsigned int irq)
 396 {
 397         struct irq_data *node;
 398         kstat_cpu(0).irqs[irq]++;
 399         node = irq_list[irq];
 400         do {
 401                 node->handler(irq, node->dev_id);
 402                 node = node->next;
 403         } while (node);
 404 }
 405
 406 asmlinkage void __m68k_handle_int(unsigned int irq, struct pt_regs *regs)
 407 {
 408         struct pt_regs *old_regs;
 409         old_regs = set_irq_regs(regs);
 410         m68k_handle_int(irq);
 411         set_irq_regs(old_regs);
 412 }
 413
 414 asmlinkage void handle_badint(struct pt_regs *regs)
 415 {
 416         kstat_cpu(0).irqs[0]++;
 417         printk("unexpected interrupt from %u\n", regs->vector);
 418 }
 419
 420 int show_interrupts(struct seq_file *p, void *v)
 421 {
 422         struct irq_chip *contr;
 423         struct irq_data *node;
 424         int i = *(loff_t *) v;
 425
 426         /* autovector interrupts */
 427         if (irq_list[i]) {
 428                 contr = irq_chip[i];
 429                 node = irq_list[i];
 430                 seq_printf(p, "%-8s %3u: %10u %s", contr->name, i, kstat_cpu(0).irqs[i], node->devname);
 431                 while ((node = node->next))
 432                         seq_printf(p, ", %s", node->devname);
 433                 seq_puts(p, "\n");
 434         }
 435         return 0;
 436 }
 437
 438 #ifdef CONFIG_PROC_FS
 439 void init_irq_proc(void)
 440 {
 441         /* Insert /proc/irq driver here */
 442 }
 443 #endif