arch/sparc/kernel/irq.c

   1 /*  $Id: irq.c,v 1.114 2001/12/11 04:55:51 davem Exp $
   2  *  arch/sparc/kernel/irq.c:  Interrupt request handling routines. On the
   3  *                            Sparc the IRQ's are basically 'cast in stone'
   4  *                            and you are supposed to probe the prom's device
   5  *                            node trees to find out who's got which IRQ.
   6  *
   7  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   8  *  Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
   9  *  Copyright (C) 1995,2002 Pete A. Zaitcev (zaitcev@yahoo.com)
  10  *  Copyright (C) 1996 Dave Redman (djhr@tadpole.co.uk)
  11  *  Copyright (C) 1998-2000 Anton Blanchard (anton@samba.org)
  12  */
  13
  14 #include <linux/config.h>
  15 #include <linux/module.h>
  16 #include <linux/sched.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/errno.h>
  19 #include <linux/linkage.h>
  20 #include <linux/kernel_stat.h>
  21 #include <linux/signal.h>
  22 #include <linux/sched.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/slab.h>
  25 #include <linux/random.h>
  26 #include <linux/init.h>
  27 #include <linux/smp.h>
  28 #include <linux/smp_lock.h>
  29 #include <linux/delay.h>
  30 #include <linux/threads.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/seq_file.h>
  33
  34 #include <asm/ptrace.h>
  35 #include <asm/processor.h>
  36 #include <asm/system.h>
  37 #include <asm/psr.h>
  38 #include <asm/smp.h>
  39 #include <asm/vaddrs.h>
  40 #include <asm/timer.h>
  41 #include <asm/openprom.h>
  42 #include <asm/oplib.h>
  43 #include <asm/traps.h>
  44 #include <asm/irq.h>
  45 #include <asm/io.h>
  46 #include <asm/pgalloc.h>
  47 #include <asm/pgtable.h>
  48 #include <asm/pcic.h>
  49 #include <asm/cacheflush.h>
  50
  51 #ifdef CONFIG_SMP
  52 #define SMP_NOP2 "nop; nop;\n\t"
  53 #define SMP_NOP3 "nop; nop; nop;\n\t"
  54 #else
  55 #define SMP_NOP2
  56 #define SMP_NOP3
  57 #endif /* SMP */
  58 unsigned long __local_irq_save(void)
  59 {
  60         unsigned long retval;
  61         unsigned long tmp;
  62
  63         __asm__ __volatile__(
  64                 "rd     %%psr, %0\n\t"
  65                 SMP_NOP3        /* Sun4m + Cypress + SMP bug */
  66                 "or     %0, %2, %1\n\t"
  67                 "wr     %1, 0, %%psr\n\t"
  68                 "nop; nop; nop\n"
  69                 : "=&r" (retval), "=r" (tmp)
  70                 : "i" (PSR_PIL)
  71                 : "memory");
  72
  73         return retval;
  74 }
  75
  76 void local_irq_enable(void)
  77 {
  78         unsigned long tmp;
  79
  80         __asm__ __volatile__(
  81                 "rd     %%psr, %0\n\t"
  82                 SMP_NOP3        /* Sun4m + Cypress + SMP bug */
  83                 "andn   %0, %1, %0\n\t"
  84                 "wr     %0, 0, %%psr\n\t"
  85                 "nop; nop; nop\n"
  86                 : "=&r" (tmp)
  87                 : "i" (PSR_PIL)
  88                 : "memory");
  89 }
  90
  91 void local_irq_restore(unsigned long old_psr)
  92 {
  93         unsigned long tmp;
  94
  95         __asm__ __volatile__(
  96                 "rd     %%psr, %0\n\t"
  97                 "and    %2, %1, %2\n\t"
  98                 SMP_NOP2        /* Sun4m + Cypress + SMP bug */
  99                 "andn   %0, %1, %0\n\t"
 100                 "wr     %0, %2, %%psr\n\t"
 101                 "nop; nop; nop\n"
 102                 : "=&r" (tmp)
 103                 : "i" (PSR_PIL), "r" (old_psr)
 104                 : "memory");
 105 }
 106
 107 EXPORT_SYMBOL(__local_irq_save);
 108 EXPORT_SYMBOL(local_irq_enable);
 109 EXPORT_SYMBOL(local_irq_restore);
 110
 111 /*
 112  * Dave Redman (djhr@tadpole.co.uk)
 113  *
 114  * IRQ numbers.. These are no longer restricted to 15..
 115  *
 116  * this is done to enable SBUS cards and onboard IO to be masked
 117  * correctly. using the interrupt level isn't good enough.
 118  *
 119  * For example:
 120  *   A device interrupting at sbus level6 and the Floppy both come in
 121  *   at IRQ11, but enabling and disabling them requires writing to
 122  *   different bits in the SLAVIO/SEC.
 123  *
 124  * As a result of these changes sun4m machines could now support
 125  * directed CPU interrupts using the existing enable/disable irq code
 126  * with tweaks.
 127  *
 128  */
 129
 130 static void irq_panic(void)
 131 {
 132     extern char *cputypval;
 133     prom_printf("machine: %s doesn't have irq handlers defined!\n",cputypval);
 134     prom_halt();
 135 }
 136
 137 void (*sparc_init_timers)(irqreturn_t (*)(int, void *,struct pt_regs *)) =
 138     (void (*)(irqreturn_t (*)(int, void *,struct pt_regs *))) irq_panic;
 139
 140 /*
 141  * Dave Redman (djhr@tadpole.co.uk)
 142  *
 143  * There used to be extern calls and hard coded values here.. very sucky!
 144  * instead, because some of the devices attach very early, I do something
 145  * equally sucky but at least we'll never try to free statically allocated
 146  * space or call kmalloc before kmalloc_init :(.
 147  *
 148  * In fact it's the timer10 that attaches first.. then timer14
 149  * then kmalloc_init is called.. then the tty interrupts attach.
 150  * hmmm....
 151  *
 152  */
 153 #define MAX_STATIC_ALLOC        4
 154 struct irqaction static_irqaction[MAX_STATIC_ALLOC];
 155 int static_irq_count;
 156
 157 struct {
 158         struct irqaction *action;
 159         int flags;
 160 } sparc_irq[NR_IRQS];
 161 #define SPARC_IRQ_INPROGRESS 1
 162
 163 /* Used to protect the IRQ action lists */
 164 DEFINE_SPINLOCK(irq_action_lock);
 165
 166 int show_interrupts(struct seq_file *p, void *v)
 167 {
 168         int i = *(loff_t *) v;
 169         struct irqaction * action;
 170         unsigned long flags;
 171 #ifdef CONFIG_SMP
 172         int j;
 173 #endif
 174
 175         if (sparc_cpu_model == sun4d) {
 176                 extern int show_sun4d_interrupts(struct seq_file *, void *);
 177
 178                 return show_sun4d_interrupts(p, v);
 179         }
 180         spin_lock_irqsave(&irq_action_lock, flags);
 181         if (i < NR_IRQS) {
 182                 action = sparc_irq[i].action;
 183                 if (!action)
 184                         goto out_unlock;
 185                 seq_printf(p, "%3d: ", i);
 186 #ifndef CONFIG_SMP
 187                 seq_printf(p, "%10u ", kstat_irqs(i));
 188 #else
 189                 for_each_online_cpu(j) {
 190                         seq_printf(p, "%10u ",
 191                                     kstat_cpu(j).irqs[i]);
 192                 }
 193 #endif
 194                 seq_printf(p, " %c %s",
 195                         (action->flags & SA_INTERRUPT) ? '+' : ' ',
 196                         action->name);
 197                 for (action=action->next; action; action = action->next) {
 198                         seq_printf(p, ",%s %s",
 199                                 (action->flags & SA_INTERRUPT) ? " +" : "",
 200                                 action->name);
 201                 }
 202                 seq_putc(p, '\n');
 203         }
 204 out_unlock:
 205         spin_unlock_irqrestore(&irq_action_lock, flags);
 206         return 0;
 207 }
 208
 209 void free_irq(unsigned int irq, void *dev_id)
 210 {
 211         struct irqaction * action;
 212         struct irqaction **actionp;
 213         unsigned long flags;
 214         unsigned int cpu_irq;
 215
 216         if (sparc_cpu_model == sun4d) {
 217                 extern void sun4d_free_irq(unsigned int, void *);
 218
 219                 sun4d_free_irq(irq, dev_id);
 220                 return;
 221         }
 222         cpu_irq = irq & (NR_IRQS - 1);
 223         if (cpu_irq > 14) {  /* 14 irq levels on the sparc */
 224                 printk("Trying to free bogus IRQ %d\n", irq);
 225                 return;
 226         }
 227
 228         spin_lock_irqsave(&irq_action_lock, flags);
 229
 230         actionp = &sparc_irq[cpu_irq].action;
 231         action = *actionp;
 232
 233         if (!action->handler) {
 234                 printk("Trying to free free IRQ%d\n",irq);
 235                 goto out_unlock;
 236         }
 237         if (dev_id) {
 238                 for (; action; action = action->next) {
 239                         if (action->dev_id == dev_id)
 240                                 break;
 241                         actionp = &action->next;
 242                 }
 243                 if (!action) {
 244                         printk("Trying to free free shared IRQ%d\n",irq);
 245                         goto out_unlock;
 246                 }
 247         } else if (action->flags & SA_SHIRQ) {
 248                 printk("Trying to free shared IRQ%d with NULL device ID\n", irq);
 249                 goto out_unlock;
 250         }
 251         if (action->flags & SA_STATIC_ALLOC)
 252         {
 253                 /* This interrupt is marked as specially allocated
 254                  * so it is a bad idea to free it.
 255                  */
 256                 printk("Attempt to free statically allocated IRQ%d (%s)\n",
 257                        irq, action->name);
 258                 goto out_unlock;
 259         }
 260
 261         *actionp = action->next;
 262
 263         spin_unlock_irqrestore(&irq_action_lock, flags);
 264
 265         synchronize_irq(irq);
 266
 267         spin_lock_irqsave(&irq_action_lock, flags);
 268
 269         kfree(action);
 270
 271         if (!sparc_irq[cpu_irq].action)
 272                 disable_irq(irq);
 273
 274 out_unlock:
 275         spin_unlock_irqrestore(&irq_action_lock, flags);
 276 }
 277
 278 EXPORT_SYMBOL(free_irq);
 279
 280 /*
 281  * This is called when we want to synchronize with
 282  * interrupts. We may for example tell a device to
 283  * stop sending interrupts: but to make sure there
 284  * are no interrupts that are executing on another
 285  * CPU we need to call this function.
 286  */
 287 #ifdef CONFIG_SMP
 288 void synchronize_irq(unsigned int irq)
 289 {
 290         unsigned int cpu_irq;
 291
 292         cpu_irq = irq & (NR_IRQS - 1);
 293         while (sparc_irq[cpu_irq].flags & SPARC_IRQ_INPROGRESS)
 294                 cpu_relax();
 295 }
 296 #endif /* SMP */
 297
 298 void unexpected_irq(int irq, void *dev_id, struct pt_regs * regs)
 299 {
 300         int i;
 301         struct irqaction * action;
 302         unsigned int cpu_irq;
 303
 304         cpu_irq = irq & (NR_IRQS - 1);
 305         action = sparc_irq[cpu_irq].action;
 306
 307         printk("IO device interrupt, irq = %d\n", irq);
 308         printk("PC = %08lx NPC = %08lx FP=%08lx\n", regs->pc,
 309                     regs->npc, regs->u_regs[14]);
 310         if (action) {
 311                 printk("Expecting: ");
 312                 for (i = 0; i < 16; i++)
 313                         if (action->handler)
 314                                 printk("[%s:%d:0x%x] ", action->name,
 315                                        (int) i, (unsigned int) action->handler);
 316         }
 317         printk("AIEEE\n");
 318         panic("bogus interrupt received");
 319 }
 320
 321 void handler_irq(int irq, struct pt_regs * regs)
 322 {
 323         struct irqaction * action;
 324         int cpu = smp_processor_id();
 325 #ifdef CONFIG_SMP
 326         extern void smp4m_irq_rotate(int cpu);
 327 #endif
 328
 329         irq_enter();
 330         disable_pil_irq(irq);
 331 #ifdef CONFIG_SMP
 332         /* Only rotate on lower priority IRQ's (scsi, ethernet, etc.). */
 333         if(irq < 10)
 334                 smp4m_irq_rotate(cpu);
 335 #endif
 336         action = sparc_irq[irq].action;
 337         sparc_irq[irq].flags |= SPARC_IRQ_INPROGRESS;
 338         kstat_cpu(cpu).irqs[irq]++;
 339         do {
 340                 if (!action || !action->handler)
 341                         unexpected_irq(irq, NULL, regs);
 342                 action->handler(irq, action->dev_id, regs);
 343                 action = action->next;
 344         } while (action);
 345         sparc_irq[irq].flags &= ~SPARC_IRQ_INPROGRESS;
 346         enable_pil_irq(irq);
 347         irq_exit();
 348 }
 349
 350 #ifdef CONFIG_BLK_DEV_FD
 351 extern void floppy_interrupt(int irq, void *dev_id, struct pt_regs *regs);
 352
 353 void sparc_floppy_irq(int irq, void *dev_id, struct pt_regs *regs)
 354 {
 355         int cpu = smp_processor_id();
 356
 357         disable_pil_irq(irq);
 358         irq_enter();
 359         kstat_cpu(cpu).irqs[irq]++;
 360         floppy_interrupt(irq, dev_id, regs);
 361         irq_exit();
 362         enable_pil_irq(irq);
 363         // XXX Eek, it's totally changed with preempt_count() and such
 364         // if (softirq_pending(cpu))
 365         //      do_softirq();
 366 }
 367 #endif
 368
 369 /* Fast IRQ's on the Sparc can only have one routine attached to them,
 370  * thus no sharing possible.
 371  */
 372 int request_fast_irq(unsigned int irq,
 373                      irqreturn_t (*handler)(int, void *, struct pt_regs *),
 374                      unsigned long irqflags, const char *devname)
 375 {
 376         struct irqaction *action;
 377         unsigned long flags;
 378         unsigned int cpu_irq;
 379         int ret;
 380 #ifdef CONFIG_SMP
 381         struct tt_entry *trap_table;
 382         extern struct tt_entry trapbase_cpu1, trapbase_cpu2, trapbase_cpu3;
 383 #endif
 384
 385         cpu_irq = irq & (NR_IRQS - 1);
 386         if(cpu_irq > 14) {
 387                 ret = -EINVAL;
 388                 goto out;
 389         }
 390         if(!handler) {
 391                 ret = -EINVAL;
 392                 goto out;
 393         }
 394
 395         spin_lock_irqsave(&irq_action_lock, flags);
 396
 397         action = sparc_irq[cpu_irq].action;
 398         if(action) {
 399                 if(action->flags & SA_SHIRQ)
 400                         panic("Trying to register fast irq when already shared.\n");
 401                 if(irqflags & SA_SHIRQ)
 402                         panic("Trying to register fast irq as shared.\n");
 403
 404                 /* Anyway, someone already owns it so cannot be made fast. */
 405                 printk("request_fast_irq: Trying to register yet already owned.\n");
 406                 ret = -EBUSY;
 407                 goto out_unlock;
 408         }
 409
 410         /* If this is flagged as statically allocated then we use our
 411          * private struct which is never freed.
 412          */
 413         if (irqflags & SA_STATIC_ALLOC) {
 414             if (static_irq_count < MAX_STATIC_ALLOC)
 415                 action = &static_irqaction[static_irq_count++];
 416             else
 417                 printk("Fast IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n",
 418                        irq, devname);
 419         }
 420
 421         if (action == NULL)
 422             action = (struct irqaction *)kmalloc(sizeof(struct irqaction),
 423                                                  GFP_ATOMIC);
 424
 425         if (!action) {
 426                 ret = -ENOMEM;
 427                 goto out_unlock;
 428         }
 429
 430         /* Dork with trap table if we get this far. */
 431 #define INSTANTIATE(table) \
 432         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_one = SPARC_RD_PSR_L0; \
 433         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two = \
 434                 SPARC_BRANCH((unsigned long) handler, \
 435                              (unsigned long) &table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two);\
 436         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_three = SPARC_RD_WIM_L3; \
 437         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_four = SPARC_NOP;
 438
 439         INSTANTIATE(sparc_ttable)
 440 #ifdef CONFIG_SMP
 441         trap_table = &trapbase_cpu1; INSTANTIATE(trap_table)
 442         trap_table = &trapbase_cpu2; INSTANTIATE(trap_table)
 443         trap_table = &trapbase_cpu3; INSTANTIATE(trap_table)
 444 #endif
 445 #undef INSTANTIATE
 446         /*
 447          * XXX Correct thing whould be to flush only I- and D-cache lines
 448          * which contain the handler in question. But as of time of the
 449          * writing we have no CPU-neutral interface to fine-grained flushes.
 450          */
 451         flush_cache_all();
 452
 453         action->handler = handler;
 454         action->flags = irqflags;
 455         cpus_clear(action->mask);
 456         action->name = devname;
 457         action->dev_id = NULL;
 458         action->next = NULL;
 459
 460         sparc_irq[cpu_irq].action = action;
 461
 462         enable_irq(irq);
 463
 464         ret = 0;
 465 out_unlock:
 466         spin_unlock_irqrestore(&irq_action_lock, flags);
 467 out:
 468         return ret;
 469 }
 470
 471 int request_irq(unsigned int irq,
 472                 irqreturn_t (*handler)(int, void *, struct pt_regs *),
 473                 unsigned long irqflags, const char * devname, void *dev_id)
 474 {
 475         struct irqaction * action, **actionp;
 476         unsigned long flags;
 477         unsigned int cpu_irq;
 478         int ret;
 479
 480         if (sparc_cpu_model == sun4d) {
 481                 extern int sun4d_request_irq(unsigned int,
 482                                              irqreturn_t (*)(int, void *, struct pt_regs *),
 483                                              unsigned long, const char *, void *);
 484                 return sun4d_request_irq(irq, handler, irqflags, devname, dev_id);
 485         }
 486         cpu_irq = irq & (NR_IRQS - 1);
 487         if(cpu_irq > 14) {
 488                 ret = -EINVAL;
 489                 goto out;
 490         }
 491         if (!handler) {
 492                 ret = -EINVAL;
 493                 goto out;
 494         }
 495
 496         spin_lock_irqsave(&irq_action_lock, flags);
 497
 498         actionp = &sparc_irq[cpu_irq].action;
 499         action = *actionp;
 500         if (action) {
 501                 if (!(action->flags & SA_SHIRQ) || !(irqflags & SA_SHIRQ)) {
 502                         ret = -EBUSY;
 503                         goto out_unlock;
 504                 }
 505                 if ((action->flags & SA_INTERRUPT) != (irqflags & SA_INTERRUPT)) {
 506                         printk("Attempt to mix fast and slow interrupts on IRQ%d denied\n", irq);
 507                         ret = -EBUSY;
 508                         goto out_unlock;
 509                 }
 510                 for ( ; action; action = *actionp)
 511                         actionp = &action->next;
 512         }
 513
 514         /* If this is flagged as statically allocated then we use our
 515          * private struct which is never freed.
 516          */
 517         if (irqflags & SA_STATIC_ALLOC) {
 518                 if (static_irq_count < MAX_STATIC_ALLOC)
 519                         action = &static_irqaction[static_irq_count++];
 520                 else
 521                         printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n", irq, devname);
 522         }
 523
 524         if (action == NULL)
 525                 action = (struct irqaction *)kmalloc(sizeof(struct irqaction),
 526                                                      GFP_ATOMIC);
 527
 528         if (!action) {
 529                 ret = -ENOMEM;
 530                 goto out_unlock;
 531         }
 532
 533         action->handler = handler;
 534         action->flags = irqflags;
 535         cpus_clear(action->mask);
 536         action->name = devname;
 537         action->next = NULL;
 538         action->dev_id = dev_id;
 539
 540         *actionp = action;
 541
 542         enable_irq(irq);
 543
 544         ret = 0;
 545 out_unlock:
 546         spin_unlock_irqrestore(&irq_action_lock, flags);
 547 out:
 548         return ret;
 549 }
 550
 551 EXPORT_SYMBOL(request_irq);
 552
 553 /* We really don't need these at all on the Sparc.  We only have
 554  * stubs here because they are exported to modules.
 555  */
 556 unsigned long probe_irq_on(void)
 557 {
 558         return 0;
 559 }
 560
 561 EXPORT_SYMBOL(probe_irq_on);
 562
 563 int probe_irq_off(unsigned long mask)
 564 {
 565         return 0;
 566 }
 567
 568 EXPORT_SYMBOL(probe_irq_off);
 569
 570 /* djhr
 571  * This could probably be made indirect too and assigned in the CPU
 572  * bits of the code. That would be much nicer I think and would also
 573  * fit in with the idea of being able to tune your kernel for your machine
 574  * by removing unrequired machine and device support.
 575  *
 576  */
 577
 578 void __init init_IRQ(void)
 579 {
 580         extern void sun4c_init_IRQ( void );
 581         extern void sun4m_init_IRQ( void );
 582         extern void sun4d_init_IRQ( void );
 583
 584         switch(sparc_cpu_model) {
 585         case sun4c:
 586         case sun4:
 587                 sun4c_init_IRQ();
 588                 break;
 589
 590         case sun4m:
 591 #ifdef CONFIG_PCI
 592                 pcic_probe();
 593                 if (pcic_present()) {
 594                         sun4m_pci_init_IRQ();
 595                         break;
 596                 }
 597 #endif
 598                 sun4m_init_IRQ();
 599                 break;
 600
 601         case sun4d:
 602                 sun4d_init_IRQ();
 603                 break;
 604
 605         default:
 606                 prom_printf("Cannot initialize IRQ's on this Sun machine...");
 607                 break;
 608         }
 609         btfixup();
 610 }
 611
 612 void init_irq_proc(void)
 613 {
 614         /* For now, nothing... */
 615 }