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/kernel_stat.h>
  32 #include <linux/errno.h>
  33 #include <linux/init.h>
  34
  35 #include <asm/setup.h>
  36 #include <asm/system.h>
  37 #include <asm/irq.h>
  38 #include <asm/traps.h>
  39 #include <asm/page.h>
  40 #include <asm/machdep.h>
  41 #include <asm/cacheflush.h>
  42
  43 #ifdef CONFIG_Q40
  44 #include <asm/q40ints.h>
  45 #endif
  46
  47 extern u32 auto_irqhandler_fixup[];
  48 extern u32 user_irqhandler_fixup[];
  49 extern u16 user_irqvec_fixup[];
  50
  51 /* table for system interrupt handlers */
  52 static struct irq_node *irq_list[NR_IRQS];
  53 static struct irq_controller *irq_controller[NR_IRQS];
  54 static int irq_depth[NR_IRQS];
  55
  56 static int m68k_first_user_vec;
  57
  58 static struct irq_controller auto_irq_controller = {
  59         .name           = "auto",
  60         .lock           = SPIN_LOCK_UNLOCKED,
  61         .startup        = m68k_irq_startup,
  62         .shutdown       = m68k_irq_shutdown,
  63 };
  64
  65 static struct irq_controller user_irq_controller = {
  66         .name           = "user",
  67         .lock           = SPIN_LOCK_UNLOCKED,
  68         .startup        = m68k_irq_startup,
  69         .shutdown       = m68k_irq_shutdown,
  70 };
  71
  72 #define NUM_IRQ_NODES 100
  73 static irq_node_t 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_controller[i] = &auto_irq_controller;
  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         m68k_first_user_vec = vec;
 135         for (i = 0; i < cnt; i++)
 136                 irq_controller[IRQ_USER + i] = &user_irq_controller;
 137         *user_irqvec_fixup = vec - IRQ_USER;
 138         if (handler)
 139                 *user_irqhandler_fixup = (u32)handler;
 140         flush_icache();
 141 }
 142
 143 /**
 144  * m68k_setup_irq_controller
 145  * @contr: irq controller which controls specified irq
 146  * @irq: first irq to be managed by the controller
 147  *
 148  * Change the controller for the specified range of irq, which will be used to
 149  * manage these irq. auto/user irq already have a default controller, which can
 150  * be changed as well, but the controller probably should use m68k_irq_startup/
 151  * m68k_irq_shutdown.
 152  */
 153 void m68k_setup_irq_controller(struct irq_controller *contr, unsigned int irq,
 154                                unsigned int cnt)
 155 {
 156         int i;
 157
 158         for (i = 0; i < cnt; i++)
 159                 irq_controller[irq + i] = contr;
 160 }
 161
 162 irq_node_t *new_irq_node(void)
 163 {
 164         irq_node_t *node;
 165         short i;
 166
 167         for (node = nodes, i = NUM_IRQ_NODES-1; i >= 0; node++, i--) {
 168                 if (!node->handler) {
 169                         memset(node, 0, sizeof(*node));
 170                         return node;
 171                 }
 172         }
 173
 174         printk ("new_irq_node: out of nodes\n");
 175         return NULL;
 176 }
 177
 178 int setup_irq(unsigned int irq, struct irq_node *node)
 179 {
 180         struct irq_controller *contr;
 181         struct irq_node **prev;
 182         unsigned long flags;
 183
 184         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 185                 printk("%s: Incorrect IRQ %d from %s\n",
 186                        __FUNCTION__, irq, node->devname);
 187                 return -ENXIO;
 188         }
 189
 190         spin_lock_irqsave(&contr->lock, flags);
 191
 192         prev = irq_list + irq;
 193         if (*prev) {
 194                 /* Can't share interrupts unless both agree to */
 195                 if (!((*prev)->flags & node->flags & IRQF_SHARED)) {
 196                         spin_unlock_irqrestore(&contr->lock, flags);
 197                         return -EBUSY;
 198                 }
 199                 while (*prev)
 200                         prev = &(*prev)->next;
 201         }
 202
 203         if (!irq_list[irq]) {
 204                 if (contr->startup)
 205                         contr->startup(irq);
 206                 else
 207                         contr->enable(irq);
 208         }
 209         node->next = NULL;
 210         *prev = node;
 211
 212         spin_unlock_irqrestore(&contr->lock, flags);
 213
 214         return 0;
 215 }
 216
 217 int request_irq(unsigned int irq,
 218                 irqreturn_t (*handler) (int, void *, struct pt_regs *),
 219                 unsigned long flags, const char *devname, void *dev_id)
 220 {
 221         struct irq_node *node;
 222         int res;
 223
 224         node = new_irq_node();
 225         if (!node)
 226                 return -ENOMEM;
 227
 228         node->handler = handler;
 229         node->flags   = flags;
 230         node->dev_id  = dev_id;
 231         node->devname = devname;
 232
 233         res = setup_irq(irq, node);
 234         if (res)
 235                 node->handler = NULL;
 236
 237         return res;
 238 }
 239
 240 EXPORT_SYMBOL(request_irq);
 241
 242 void free_irq(unsigned int irq, void *dev_id)
 243 {
 244         struct irq_controller *contr;
 245         struct irq_node **p, *node;
 246         unsigned long flags;
 247
 248         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 249                 printk("%s: Incorrect IRQ %d\n", __FUNCTION__, irq);
 250                 return;
 251         }
 252
 253         spin_lock_irqsave(&contr->lock, flags);
 254
 255         p = irq_list + irq;
 256         while ((node = *p)) {
 257                 if (node->dev_id == dev_id)
 258                         break;
 259                 p = &node->next;
 260         }
 261
 262         if (node) {
 263                 *p = node->next;
 264                 node->handler = NULL;
 265         } else
 266                 printk("%s: Removing probably wrong IRQ %d\n",
 267                        __FUNCTION__, irq);
 268
 269         if (!irq_list[irq]) {
 270                 if (contr->shutdown)
 271                         contr->shutdown(irq);
 272                 else
 273                         contr->disable(irq);
 274         }
 275
 276         spin_unlock_irqrestore(&contr->lock, flags);
 277 }
 278
 279 EXPORT_SYMBOL(free_irq);
 280
 281 void enable_irq(unsigned int irq)
 282 {
 283         struct irq_controller *contr;
 284         unsigned long flags;
 285
 286         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 287                 printk("%s: Incorrect IRQ %d\n",
 288                        __FUNCTION__, irq);
 289                 return;
 290         }
 291
 292         spin_lock_irqsave(&contr->lock, flags);
 293         if (irq_depth[irq]) {
 294                 if (!--irq_depth[irq]) {
 295                         if (contr->enable)
 296                                 contr->enable(irq);
 297                 }
 298         } else
 299                 WARN_ON(1);
 300         spin_unlock_irqrestore(&contr->lock, flags);
 301 }
 302
 303 EXPORT_SYMBOL(enable_irq);
 304
 305 void disable_irq(unsigned int irq)
 306 {
 307         struct irq_controller *contr;
 308         unsigned long flags;
 309
 310         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 311                 printk("%s: Incorrect IRQ %d\n",
 312                        __FUNCTION__, irq);
 313                 return;
 314         }
 315
 316         spin_lock_irqsave(&contr->lock, flags);
 317         if (!irq_depth[irq]++) {
 318                 if (contr->disable)
 319                         contr->disable(irq);
 320         }
 321         spin_unlock_irqrestore(&contr->lock, flags);
 322 }
 323
 324 EXPORT_SYMBOL(disable_irq);
 325
 326 int m68k_irq_startup(unsigned int irq)
 327 {
 328         if (irq <= IRQ_AUTO_7)
 329                 vectors[VEC_SPUR + irq] = auto_inthandler;
 330         else
 331                 vectors[m68k_first_user_vec + irq - IRQ_USER] = user_inthandler;
 332         return 0;
 333 }
 334
 335 void m68k_irq_shutdown(unsigned int irq)
 336 {
 337         if (irq <= IRQ_AUTO_7)
 338                 vectors[VEC_SPUR + irq] = bad_inthandler;
 339         else
 340                 vectors[m68k_first_user_vec + irq - IRQ_USER] = bad_inthandler;
 341 }
 342
 343
 344 /*
 345  * Do we need these probe functions on the m68k?
 346  *
 347  *  ... may be useful with ISA devices
 348  */
 349 unsigned long probe_irq_on (void)
 350 {
 351 #ifdef CONFIG_Q40
 352         if (MACH_IS_Q40)
 353                 return q40_probe_irq_on();
 354 #endif
 355         return 0;
 356 }
 357
 358 EXPORT_SYMBOL(probe_irq_on);
 359
 360 int probe_irq_off (unsigned long irqs)
 361 {
 362 #ifdef CONFIG_Q40
 363         if (MACH_IS_Q40)
 364                 return q40_probe_irq_off(irqs);
 365 #endif
 366         return 0;
 367 }
 368
 369 EXPORT_SYMBOL(probe_irq_off);
 370
 371 unsigned int irq_canonicalize(unsigned int irq)
 372 {
 373 #ifdef CONFIG_Q40
 374         if (MACH_IS_Q40 && irq == 11)
 375                 irq = 10;
 376 #endif
 377         return irq;
 378 }
 379
 380 EXPORT_SYMBOL(irq_canonicalize);
 381
 382 asmlinkage void m68k_handle_int(unsigned int irq, struct pt_regs *regs)
 383 {
 384         struct irq_node *node;
 385
 386         kstat_cpu(0).irqs[irq]++;
 387         node = irq_list[irq];
 388         do {
 389                 node->handler(irq, node->dev_id, regs);
 390                 node = node->next;
 391         } while (node);
 392 }
 393
 394 asmlinkage void handle_badint(struct pt_regs *regs)
 395 {
 396         kstat_cpu(0).irqs[0]++;
 397         printk("unexpected interrupt from %u\n", regs->vector);
 398 }
 399
 400 int show_interrupts(struct seq_file *p, void *v)
 401 {
 402         struct irq_controller *contr;
 403         struct irq_node *node;
 404         int i = *(loff_t *) v;
 405
 406         /* autovector interrupts */
 407         if (irq_list[i]) {
 408                 contr = irq_controller[i];
 409                 node = irq_list[i];
 410                 seq_printf(p, "%-8s %3u: %10u %s", contr->name, i, kstat_cpu(0).irqs[i], node->devname);
 411                 while ((node = node->next))
 412                         seq_printf(p, ", %s", node->devname);
 413                 seq_puts(p, "\n");
 414         }
 415         return 0;
 416 }
 417
 418 void init_irq_proc(void)
 419 {
 420         /* Insert /proc/irq driver here */
 421 }
 422