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 #include <asm/irq_regs.h>
  43
  44 #ifdef CONFIG_Q40
  45 #include <asm/q40ints.h>
  46 #endif
  47
  48 extern u32 auto_irqhandler_fixup[];
  49 extern u32 user_irqhandler_fixup[];
  50 extern u16 user_irqvec_fixup[];
  51
  52 /* table for system interrupt handlers */
  53 static struct irq_node *irq_list[NR_IRQS];
  54 static struct irq_controller *irq_controller[NR_IRQS];
  55 static int irq_depth[NR_IRQS];
  56
  57 static int m68k_first_user_vec;
  58
  59 static struct irq_controller auto_irq_controller = {
  60         .name           = "auto",
  61         .lock           = SPIN_LOCK_UNLOCKED,
  62         .startup        = m68k_irq_startup,
  63         .shutdown       = m68k_irq_shutdown,
  64 };
  65
  66 static struct irq_controller user_irq_controller = {
  67         .name           = "user",
  68         .lock           = SPIN_LOCK_UNLOCKED,
  69         .startup        = m68k_irq_startup,
  70         .shutdown       = m68k_irq_shutdown,
  71 };
  72
  73 #define NUM_IRQ_NODES 100
  74 static irq_node_t nodes[NUM_IRQ_NODES];
  75
  76 /*
  77  * void init_IRQ(void)
  78  *
  79  * Parameters:  None
  80  *
  81  * Returns:     Nothing
  82  *
  83  * This function should be called during kernel startup to initialize
  84  * the IRQ handling routines.
  85  */
  86
  87 void __init init_IRQ(void)
  88 {
  89         int i;
  90
  91         /* assembly irq entry code relies on this... */
  92         if (HARDIRQ_MASK != 0x00ff0000) {
  93                 extern void hardirq_mask_is_broken(void);
  94                 hardirq_mask_is_broken();
  95         }
  96
  97         for (i = IRQ_AUTO_1; i <= IRQ_AUTO_7; i++)
  98                 irq_controller[i] = &auto_irq_controller;
  99
 100         mach_init_IRQ();
 101 }
 102
 103 /**
 104  * m68k_setup_auto_interrupt
 105  * @handler: called from auto vector interrupts
 106  *
 107  * setup the handler to be called from auto vector interrupts instead of the
 108  * standard __m68k_handle_int(), it will be called with irq numbers in the range
 109  * from IRQ_AUTO_1 - IRQ_AUTO_7.
 110  */
 111 void __init m68k_setup_auto_interrupt(void (*handler)(unsigned int, struct pt_regs *))
 112 {
 113         if (handler)
 114                 *auto_irqhandler_fixup = (u32)handler;
 115         flush_icache();
 116 }
 117
 118 /**
 119  * m68k_setup_user_interrupt
 120  * @vec: first user vector interrupt to handle
 121  * @cnt: number of active user vector interrupts
 122  * @handler: called from user vector interrupts
 123  *
 124  * setup user vector interrupts, this includes activating the specified range
 125  * of interrupts, only then these interrupts can be requested (note: this is
 126  * different from auto vector interrupts). An optional handler can be installed
 127  * to be called instead of the default __m68k_handle_int(), it will be called
 128  * with irq numbers starting from IRQ_USER.
 129  */
 130 void __init m68k_setup_user_interrupt(unsigned int vec, unsigned int cnt,
 131                                       void (*handler)(unsigned int, struct pt_regs *))
 132 {
 133         int i;
 134
 135         BUG_ON(IRQ_USER + cnt >= NR_IRQS);
 136         m68k_first_user_vec = vec;
 137         for (i = 0; i < cnt; i++)
 138                 irq_controller[IRQ_USER + i] = &user_irq_controller;
 139         *user_irqvec_fixup = vec - IRQ_USER;
 140         if (handler)
 141                 *user_irqhandler_fixup = (u32)handler;
 142         flush_icache();
 143 }
 144
 145 /**
 146  * m68k_setup_irq_controller
 147  * @contr: irq controller which controls specified irq
 148  * @irq: first irq to be managed by the controller
 149  *
 150  * Change the controller for the specified range of irq, which will be used to
 151  * manage these irq. auto/user irq already have a default controller, which can
 152  * be changed as well, but the controller probably should use m68k_irq_startup/
 153  * m68k_irq_shutdown.
 154  */
 155 void m68k_setup_irq_controller(struct irq_controller *contr, unsigned int irq,
 156                                unsigned int cnt)
 157 {
 158         int i;
 159
 160         for (i = 0; i < cnt; i++)
 161                 irq_controller[irq + i] = contr;
 162 }
 163
 164 irq_node_t *new_irq_node(void)
 165 {
 166         irq_node_t *node;
 167         short i;
 168
 169         for (node = nodes, i = NUM_IRQ_NODES-1; i >= 0; node++, i--) {
 170                 if (!node->handler) {
 171                         memset(node, 0, sizeof(*node));
 172                         return node;
 173                 }
 174         }
 175
 176         printk ("new_irq_node: out of nodes\n");
 177         return NULL;
 178 }
 179
 180 int setup_irq(unsigned int irq, struct irq_node *node)
 181 {
 182         struct irq_controller *contr;
 183         struct irq_node **prev;
 184         unsigned long flags;
 185
 186         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 187                 printk("%s: Incorrect IRQ %d from %s\n",
 188                        __FUNCTION__, irq, node->devname);
 189                 return -ENXIO;
 190         }
 191
 192         spin_lock_irqsave(&contr->lock, flags);
 193
 194         prev = irq_list + irq;
 195         if (*prev) {
 196                 /* Can't share interrupts unless both agree to */
 197                 if (!((*prev)->flags & node->flags & IRQF_SHARED)) {
 198                         spin_unlock_irqrestore(&contr->lock, flags);
 199                         return -EBUSY;
 200                 }
 201                 while (*prev)
 202                         prev = &(*prev)->next;
 203         }
 204
 205         if (!irq_list[irq]) {
 206                 if (contr->startup)
 207                         contr->startup(irq);
 208                 else
 209                         contr->enable(irq);
 210         }
 211         node->next = NULL;
 212         *prev = node;
 213
 214         spin_unlock_irqrestore(&contr->lock, flags);
 215
 216         return 0;
 217 }
 218
 219 int request_irq(unsigned int irq,
 220                 irq_handler_t handler,
 221                 unsigned long flags, const char *devname, void *dev_id)
 222 {
 223         struct irq_node *node;
 224         int res;
 225
 226         node = new_irq_node();
 227         if (!node)
 228                 return -ENOMEM;
 229
 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_controller *contr;
 247         struct irq_node **p, *node;
 248         unsigned long flags;
 249
 250         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 251                 printk("%s: Incorrect IRQ %d\n", __FUNCTION__, irq);
 252                 return;
 253         }
 254
 255         spin_lock_irqsave(&contr->lock, 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                        __FUNCTION__, irq);
 270
 271         if (!irq_list[irq]) {
 272                 if (contr->shutdown)
 273                         contr->shutdown(irq);
 274                 else
 275                         contr->disable(irq);
 276         }
 277
 278         spin_unlock_irqrestore(&contr->lock, flags);
 279 }
 280
 281 EXPORT_SYMBOL(free_irq);
 282
 283 void enable_irq(unsigned int irq)
 284 {
 285         struct irq_controller *contr;
 286         unsigned long flags;
 287
 288         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 289                 printk("%s: Incorrect IRQ %d\n",
 290                        __FUNCTION__, irq);
 291                 return;
 292         }
 293
 294         spin_lock_irqsave(&contr->lock, flags);
 295         if (irq_depth[irq]) {
 296                 if (!--irq_depth[irq]) {
 297                         if (contr->enable)
 298                                 contr->enable(irq);
 299                 }
 300         } else
 301                 WARN_ON(1);
 302         spin_unlock_irqrestore(&contr->lock, flags);
 303 }
 304
 305 EXPORT_SYMBOL(enable_irq);
 306
 307 void disable_irq(unsigned int irq)
 308 {
 309         struct irq_controller *contr;
 310         unsigned long flags;
 311
 312         if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 313                 printk("%s: Incorrect IRQ %d\n",
 314                        __FUNCTION__, irq);
 315                 return;
 316         }
 317
 318         spin_lock_irqsave(&contr->lock, flags);
 319         if (!irq_depth[irq]++) {
 320                 if (contr->disable)
 321                         contr->disable(irq);
 322         }
 323         spin_unlock_irqrestore(&contr->lock, flags);
 324 }
 325
 326 EXPORT_SYMBOL(disable_irq);
 327
 328 int m68k_irq_startup(unsigned int irq)
 329 {
 330         if (irq <= IRQ_AUTO_7)
 331                 vectors[VEC_SPUR + irq] = auto_inthandler;
 332         else
 333                 vectors[m68k_first_user_vec + irq - IRQ_USER] = user_inthandler;
 334         return 0;
 335 }
 336
 337 void m68k_irq_shutdown(unsigned int irq)
 338 {
 339         if (irq <= IRQ_AUTO_7)
 340                 vectors[VEC_SPUR + irq] = bad_inthandler;
 341         else
 342                 vectors[m68k_first_user_vec + irq - IRQ_USER] = bad_inthandler;
 343 }
 344
 345
 346 /*
 347  * Do we need these probe functions on the m68k?
 348  *
 349  *  ... may be useful with ISA devices
 350  */
 351 unsigned long probe_irq_on (void)
 352 {
 353 #ifdef CONFIG_Q40
 354         if (MACH_IS_Q40)
 355                 return q40_probe_irq_on();
 356 #endif
 357         return 0;
 358 }
 359
 360 EXPORT_SYMBOL(probe_irq_on);
 361
 362 int probe_irq_off (unsigned long irqs)
 363 {
 364 #ifdef CONFIG_Q40
 365         if (MACH_IS_Q40)
 366                 return q40_probe_irq_off(irqs);
 367 #endif
 368         return 0;
 369 }
 370
 371 EXPORT_SYMBOL(probe_irq_off);
 372
 373 unsigned int irq_canonicalize(unsigned int irq)
 374 {
 375 #ifdef CONFIG_Q40
 376         if (MACH_IS_Q40 && irq == 11)
 377                 irq = 10;
 378 #endif
 379         return irq;
 380 }
 381
 382 EXPORT_SYMBOL(irq_canonicalize);
 383
 384 asmlinkage void m68k_handle_int(unsigned int irq)
 385 {
 386         struct irq_node *node;
 387         kstat_cpu(0).irqs[irq]++;
 388         node = irq_list[irq];
 389         do {
 390                 node->handler(irq, node->dev_id);
 391                 node = node->next;
 392         } while (node);
 393 }
 394
 395 asmlinkage void __m68k_handle_int(unsigned int irq, struct pt_regs *regs)
 396 {
 397         struct pt_regs *old_regs;
 398         old_regs = set_irq_regs(regs);
 399         m68k_handle_int(irq);
 400         set_irq_regs(old_regs);
 401 }
 402
 403 asmlinkage void handle_badint(struct pt_regs *regs)
 404 {
 405         kstat_cpu(0).irqs[0]++;
 406         printk("unexpected interrupt from %u\n", regs->vector);
 407 }
 408
 409 int show_interrupts(struct seq_file *p, void *v)
 410 {
 411         struct irq_controller *contr;
 412         struct irq_node *node;
 413         int i = *(loff_t *) v;
 414
 415         /* autovector interrupts */
 416         if (irq_list[i]) {
 417                 contr = irq_controller[i];
 418                 node = irq_list[i];
 419                 seq_printf(p, "%-8s %3u: %10u %s", contr->name, i, kstat_cpu(0).irqs[i], node->devname);
 420                 while ((node = node->next))
 421                         seq_printf(p, ", %s", node->devname);
 422                 seq_puts(p, "\n");
 423         }
 424         return 0;
 425 }
 426
 427 void init_irq_proc(void)
 428 {
 429         /* Insert /proc/irq driver here */
 430 }
 431