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   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/module.h>
  15 #include <linux/sched.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/errno.h>
  18 #include <linux/linkage.h>
  19 #include <linux/kernel_stat.h>
  20 #include <linux/signal.h>
  21 #include <linux/sched.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/slab.h>
  24 #include <linux/random.h>
  25 #include <linux/init.h>
  26 #include <linux/smp.h>
  27 #include <linux/smp_lock.h>
  28 #include <linux/delay.h>
  29 #include <linux/threads.h>
  30 #include <linux/spinlock.h>
  31 #include <linux/seq_file.h>
  32
  33 #include <asm/ptrace.h>
  34 #include <asm/processor.h>
  35 #include <asm/system.h>
  36 #include <asm/psr.h>
  37 #include <asm/smp.h>
  38 #include <asm/vaddrs.h>
  39 #include <asm/timer.h>
  40 #include <asm/openprom.h>
  41 #include <asm/oplib.h>
  42 #include <asm/traps.h>
  43 #include <asm/irq.h>
  44 #include <asm/io.h>
  45 #include <asm/pgalloc.h>
  46 #include <asm/pgtable.h>
  47 #include <asm/pcic.h>
  48 #include <asm/cacheflush.h>
  49 #include <asm/irq_regs.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)(irq_handler_t ) =
 138     (void (*)(irq_handler_t )) 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 & IRQF_DISABLED) ? '+' : ' ',
 196                         action->name);
 197                 for (action=action->next; action; action = action->next) {
 198                         seq_printf(p, ",%s %s",
 199                                 (action->flags & IRQF_DISABLED) ? " +" : "",
 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 & IRQF_SHARED) {
 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 pt_regs *old_regs;
 324         struct irqaction * action;
 325         int cpu = smp_processor_id();
 326 #ifdef CONFIG_SMP
 327         extern void smp4m_irq_rotate(int cpu);
 328 #endif
 329
 330         old_regs = set_irq_regs(regs);
 331         irq_enter();
 332         disable_pil_irq(irq);
 333 #ifdef CONFIG_SMP
 334         /* Only rotate on lower priority IRQ's (scsi, ethernet, etc.). */
 335         if((sparc_cpu_model==sun4m) && (irq < 10))
 336                 smp4m_irq_rotate(cpu);
 337 #endif
 338         action = sparc_irq[irq].action;
 339         sparc_irq[irq].flags |= SPARC_IRQ_INPROGRESS;
 340         kstat_cpu(cpu).irqs[irq]++;
 341         do {
 342                 if (!action || !action->handler)
 343                         unexpected_irq(irq, NULL, regs);
 344                 action->handler(irq, action->dev_id);
 345                 action = action->next;
 346         } while (action);
 347         sparc_irq[irq].flags &= ~SPARC_IRQ_INPROGRESS;
 348         enable_pil_irq(irq);
 349         irq_exit();
 350         set_irq_regs(old_regs);
 351 }
 352
 353 #ifdef CONFIG_BLK_DEV_FD
 354 extern void floppy_interrupt(int irq, void *dev_id);
 355
 356 void sparc_floppy_irq(int irq, void *dev_id, struct pt_regs *regs)
 357 {
 358         struct pt_regs *old_regs;
 359         int cpu = smp_processor_id();
 360
 361         old_regs = set_irq_regs(regs);
 362         disable_pil_irq(irq);
 363         irq_enter();
 364         kstat_cpu(cpu).irqs[irq]++;
 365         floppy_interrupt(irq, dev_id);
 366         irq_exit();
 367         enable_pil_irq(irq);
 368         set_irq_regs(old_regs);
 369         // XXX Eek, it's totally changed with preempt_count() and such
 370         // if (softirq_pending(cpu))
 371         //      do_softirq();
 372 }
 373 #endif
 374
 375 /* Fast IRQ's on the Sparc can only have one routine attached to them,
 376  * thus no sharing possible.
 377  */
 378 int request_fast_irq(unsigned int irq,
 379                      irq_handler_t handler,
 380                      unsigned long irqflags, const char *devname)
 381 {
 382         struct irqaction *action;
 383         unsigned long flags;
 384         unsigned int cpu_irq;
 385         int ret;
 386 #ifdef CONFIG_SMP
 387         struct tt_entry *trap_table;
 388         extern struct tt_entry trapbase_cpu1, trapbase_cpu2, trapbase_cpu3;
 389 #endif
 390
 391         cpu_irq = irq & (NR_IRQS - 1);
 392         if(cpu_irq > 14) {
 393                 ret = -EINVAL;
 394                 goto out;
 395         }
 396         if(!handler) {
 397                 ret = -EINVAL;
 398                 goto out;
 399         }
 400
 401         spin_lock_irqsave(&irq_action_lock, flags);
 402
 403         action = sparc_irq[cpu_irq].action;
 404         if(action) {
 405                 if(action->flags & IRQF_SHARED)
 406                         panic("Trying to register fast irq when already shared.\n");
 407                 if(irqflags & IRQF_SHARED)
 408                         panic("Trying to register fast irq as shared.\n");
 409
 410                 /* Anyway, someone already owns it so cannot be made fast. */
 411                 printk("request_fast_irq: Trying to register yet already owned.\n");
 412                 ret = -EBUSY;
 413                 goto out_unlock;
 414         }
 415
 416         /* If this is flagged as statically allocated then we use our
 417          * private struct which is never freed.
 418          */
 419         if (irqflags & SA_STATIC_ALLOC) {
 420             if (static_irq_count < MAX_STATIC_ALLOC)
 421                 action = &static_irqaction[static_irq_count++];
 422             else
 423                 printk("Fast IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n",
 424                        irq, devname);
 425         }
 426
 427         if (action == NULL)
 428             action = kmalloc(sizeof(struct irqaction),
 429                                                  GFP_ATOMIC);
 430
 431         if (!action) {
 432                 ret = -ENOMEM;
 433                 goto out_unlock;
 434         }
 435
 436         /* Dork with trap table if we get this far. */
 437 #define INSTANTIATE(table) \
 438         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_one = SPARC_RD_PSR_L0; \
 439         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two = \
 440                 SPARC_BRANCH((unsigned long) handler, \
 441                              (unsigned long) &table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two);\
 442         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_three = SPARC_RD_WIM_L3; \
 443         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_four = SPARC_NOP;
 444
 445         INSTANTIATE(sparc_ttable)
 446 #ifdef CONFIG_SMP
 447         trap_table = &trapbase_cpu1; INSTANTIATE(trap_table)
 448         trap_table = &trapbase_cpu2; INSTANTIATE(trap_table)
 449         trap_table = &trapbase_cpu3; INSTANTIATE(trap_table)
 450 #endif
 451 #undef INSTANTIATE
 452         /*
 453          * XXX Correct thing whould be to flush only I- and D-cache lines
 454          * which contain the handler in question. But as of time of the
 455          * writing we have no CPU-neutral interface to fine-grained flushes.
 456          */
 457         flush_cache_all();
 458
 459         action->handler = handler;
 460         action->flags = irqflags;
 461         cpus_clear(action->mask);
 462         action->name = devname;
 463         action->dev_id = NULL;
 464         action->next = NULL;
 465
 466         sparc_irq[cpu_irq].action = action;
 467
 468         enable_irq(irq);
 469
 470         ret = 0;
 471 out_unlock:
 472         spin_unlock_irqrestore(&irq_action_lock, flags);
 473 out:
 474         return ret;
 475 }
 476
 477 int request_irq(unsigned int irq,
 478                 irq_handler_t handler,
 479                 unsigned long irqflags, const char * devname, void *dev_id)
 480 {
 481         struct irqaction * action, **actionp;
 482         unsigned long flags;
 483         unsigned int cpu_irq;
 484         int ret;
 485
 486         if (sparc_cpu_model == sun4d) {
 487                 extern int sun4d_request_irq(unsigned int,
 488                                              irq_handler_t ,
 489                                              unsigned long, const char *, void *);
 490                 return sun4d_request_irq(irq, handler, irqflags, devname, dev_id);
 491         }
 492         cpu_irq = irq & (NR_IRQS - 1);
 493         if(cpu_irq > 14) {
 494                 ret = -EINVAL;
 495                 goto out;
 496         }
 497         if (!handler) {
 498                 ret = -EINVAL;
 499                 goto out;
 500         }
 501
 502         spin_lock_irqsave(&irq_action_lock, flags);
 503
 504         actionp = &sparc_irq[cpu_irq].action;
 505         action = *actionp;
 506         if (action) {
 507                 if (!(action->flags & IRQF_SHARED) || !(irqflags & IRQF_SHARED)) {
 508                         ret = -EBUSY;
 509                         goto out_unlock;
 510                 }
 511                 if ((action->flags & IRQF_DISABLED) != (irqflags & IRQF_DISABLED)) {
 512                         printk("Attempt to mix fast and slow interrupts on IRQ%d denied\n", irq);
 513                         ret = -EBUSY;
 514                         goto out_unlock;
 515                 }
 516                 for ( ; action; action = *actionp)
 517                         actionp = &action->next;
 518         }
 519
 520         /* If this is flagged as statically allocated then we use our
 521          * private struct which is never freed.
 522          */
 523         if (irqflags & SA_STATIC_ALLOC) {
 524                 if (static_irq_count < MAX_STATIC_ALLOC)
 525                         action = &static_irqaction[static_irq_count++];
 526                 else
 527                         printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n", irq, devname);
 528         }
 529
 530         if (action == NULL)
 531                 action = kmalloc(sizeof(struct irqaction),
 532                                                      GFP_ATOMIC);
 533
 534         if (!action) {
 535                 ret = -ENOMEM;
 536                 goto out_unlock;
 537         }
 538
 539         action->handler = handler;
 540         action->flags = irqflags;
 541         cpus_clear(action->mask);
 542         action->name = devname;
 543         action->next = NULL;
 544         action->dev_id = dev_id;
 545
 546         *actionp = action;
 547
 548         enable_irq(irq);
 549
 550         ret = 0;
 551 out_unlock:
 552         spin_unlock_irqrestore(&irq_action_lock, flags);
 553 out:
 554         return ret;
 555 }
 556
 557 EXPORT_SYMBOL(request_irq);
 558
 559 /* We really don't need these at all on the Sparc.  We only have
 560  * stubs here because they are exported to modules.
 561  */
 562 unsigned long probe_irq_on(void)
 563 {
 564         return 0;
 565 }
 566
 567 EXPORT_SYMBOL(probe_irq_on);
 568
 569 int probe_irq_off(unsigned long mask)
 570 {
 571         return 0;
 572 }
 573
 574 EXPORT_SYMBOL(probe_irq_off);
 575
 576 /* djhr
 577  * This could probably be made indirect too and assigned in the CPU
 578  * bits of the code. That would be much nicer I think and would also
 579  * fit in with the idea of being able to tune your kernel for your machine
 580  * by removing unrequired machine and device support.
 581  *
 582  */
 583
 584 void __init init_IRQ(void)
 585 {
 586         extern void sun4c_init_IRQ( void );
 587         extern void sun4m_init_IRQ( void );
 588         extern void sun4d_init_IRQ( void );
 589
 590         switch(sparc_cpu_model) {
 591         case sun4c:
 592         case sun4:
 593                 sun4c_init_IRQ();
 594                 break;
 595
 596         case sun4m:
 597 #ifdef CONFIG_PCI
 598                 pcic_probe();
 599                 if (pcic_present()) {
 600                         sun4m_pci_init_IRQ();
 601                         break;
 602                 }
 603 #endif
 604                 sun4m_init_IRQ();
 605                 break;
 606
 607         case sun4d:
 608                 sun4d_init_IRQ();
 609                 break;
 610
 611         default:
 612                 prom_printf("Cannot initialize IRQ's on this Sun machine...");
 613                 break;
 614         }
 615         btfixup();
 616 }
 617
 618 void init_irq_proc(void)
 619 {
 620         /* For now, nothing... */
 621 }