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 IRQs 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/delay.h>
  28 #include <linux/threads.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/seq_file.h>
  31
  32 #include <asm/ptrace.h>
  33 #include <asm/processor.h>
  34 #include <asm/system.h>
  35 #include <asm/psr.h>
  36 #include <asm/smp.h>
  37 #include <asm/vaddrs.h>
  38 #include <asm/timer.h>
  39 #include <asm/openprom.h>
  40 #include <asm/oplib.h>
  41 #include <asm/traps.h>
  42 #include <asm/irq.h>
  43 #include <asm/io.h>
  44 #include <asm/pgalloc.h>
  45 #include <asm/pgtable.h>
  46 #include <asm/pcic.h>
  47 #include <asm/cacheflush.h>
  48 #include <asm/irq_regs.h>
  49
  50 #include "irq.h"
  51
  52 #ifdef CONFIG_SMP
  53 #define SMP_NOP2 "nop; nop;\n\t"
  54 #define SMP_NOP3 "nop; nop; nop;\n\t"
  55 #else
  56 #define SMP_NOP2
  57 #define SMP_NOP3
  58 #endif /* SMP */
  59 unsigned long __local_irq_save(void)
  60 {
  61         unsigned long retval;
  62         unsigned long tmp;
  63
  64         __asm__ __volatile__(
  65                 "rd     %%psr, %0\n\t"
  66                 SMP_NOP3        /* Sun4m + Cypress + SMP bug */
  67                 "or     %0, %2, %1\n\t"
  68                 "wr     %1, 0, %%psr\n\t"
  69                 "nop; nop; nop\n"
  70                 : "=&r" (retval), "=r" (tmp)
  71                 : "i" (PSR_PIL)
  72                 : "memory");
  73
  74         return retval;
  75 }
  76
  77 void local_irq_enable(void)
  78 {
  79         unsigned long tmp;
  80
  81         __asm__ __volatile__(
  82                 "rd     %%psr, %0\n\t"
  83                 SMP_NOP3        /* Sun4m + Cypress + SMP bug */
  84                 "andn   %0, %1, %0\n\t"
  85                 "wr     %0, 0, %%psr\n\t"
  86                 "nop; nop; nop\n"
  87                 : "=&r" (tmp)
  88                 : "i" (PSR_PIL)
  89                 : "memory");
  90 }
  91
  92 void local_irq_restore(unsigned long old_psr)
  93 {
  94         unsigned long tmp;
  95
  96         __asm__ __volatile__(
  97                 "rd     %%psr, %0\n\t"
  98                 "and    %2, %1, %2\n\t"
  99                 SMP_NOP2        /* Sun4m + Cypress + SMP bug */
 100                 "andn   %0, %1, %0\n\t"
 101                 "wr     %0, %2, %%psr\n\t"
 102                 "nop; nop; nop\n"
 103                 : "=&r" (tmp)
 104                 : "i" (PSR_PIL), "r" (old_psr)
 105                 : "memory");
 106 }
 107
 108 EXPORT_SYMBOL(__local_irq_save);
 109 EXPORT_SYMBOL(local_irq_enable);
 110 EXPORT_SYMBOL(local_irq_restore);
 111
 112 /*
 113  * Dave Redman (djhr@tadpole.co.uk)
 114  *
 115  * IRQ numbers.. These are no longer restricted to 15..
 116  *
 117  * this is done to enable SBUS cards and onboard IO to be masked
 118  * correctly. using the interrupt level isn't good enough.
 119  *
 120  * For example:
 121  *   A device interrupting at sbus level6 and the Floppy both come in
 122  *   at IRQ11, but enabling and disabling them requires writing to
 123  *   different bits in the SLAVIO/SEC.
 124  *
 125  * As a result of these changes sun4m machines could now support
 126  * directed CPU interrupts using the existing enable/disable irq code
 127  * with tweaks.
 128  *
 129  */
 130
 131 static void irq_panic(void)
 132 {
 133     extern char *cputypval;
 134     prom_printf("machine: %s doesn't have irq handlers defined!\n",cputypval);
 135     prom_halt();
 136 }
 137
 138 void (*sparc_init_timers)(irq_handler_t ) =
 139     (void (*)(irq_handler_t )) irq_panic;
 140
 141 /*
 142  * Dave Redman (djhr@tadpole.co.uk)
 143  *
 144  * There used to be extern calls and hard coded values here.. very sucky!
 145  * instead, because some of the devices attach very early, I do something
 146  * equally sucky but at least we'll never try to free statically allocated
 147  * space or call kmalloc before kmalloc_init :(.
 148  *
 149  * In fact it's the timer10 that attaches first.. then timer14
 150  * then kmalloc_init is called.. then the tty interrupts attach.
 151  * hmmm....
 152  *
 153  */
 154 #define MAX_STATIC_ALLOC        4
 155 struct irqaction static_irqaction[MAX_STATIC_ALLOC];
 156 int static_irq_count;
 157
 158 struct {
 159         struct irqaction *action;
 160         int flags;
 161 } sparc_irq[NR_IRQS];
 162 #define SPARC_IRQ_INPROGRESS 1
 163
 164 /* Used to protect the IRQ action lists */
 165 DEFINE_SPINLOCK(irq_action_lock);
 166
 167 int show_interrupts(struct seq_file *p, void *v)
 168 {
 169         int i = *(loff_t *) v;
 170         struct irqaction * action;
 171         unsigned long flags;
 172 #ifdef CONFIG_SMP
 173         int j;
 174 #endif
 175
 176         if (sparc_cpu_model == sun4d) {
 177                 extern int show_sun4d_interrupts(struct seq_file *, void *);
 178
 179                 return show_sun4d_interrupts(p, v);
 180         }
 181         spin_lock_irqsave(&irq_action_lock, flags);
 182         if (i < NR_IRQS) {
 183                 action = sparc_irq[i].action;
 184                 if (!action)
 185                         goto out_unlock;
 186                 seq_printf(p, "%3d: ", i);
 187 #ifndef CONFIG_SMP
 188                 seq_printf(p, "%10u ", kstat_irqs(i));
 189 #else
 190                 for_each_online_cpu(j) {
 191                         seq_printf(p, "%10u ",
 192                                     kstat_cpu(j).irqs[i]);
 193                 }
 194 #endif
 195                 seq_printf(p, " %c %s",
 196                         (action->flags & IRQF_DISABLED) ? '+' : ' ',
 197                         action->name);
 198                 for (action=action->next; action; action = action->next) {
 199                         seq_printf(p, ",%s %s",
 200                                 (action->flags & IRQF_DISABLED) ? " +" : "",
 201                                 action->name);
 202                 }
 203                 seq_putc(p, '\n');
 204         }
 205 out_unlock:
 206         spin_unlock_irqrestore(&irq_action_lock, flags);
 207         return 0;
 208 }
 209
 210 void free_irq(unsigned int irq, void *dev_id)
 211 {
 212         struct irqaction * action;
 213         struct irqaction **actionp;
 214         unsigned long flags;
 215         unsigned int cpu_irq;
 216
 217         if (sparc_cpu_model == sun4d) {
 218                 extern void sun4d_free_irq(unsigned int, void *);
 219
 220                 sun4d_free_irq(irq, dev_id);
 221                 return;
 222         }
 223         cpu_irq = irq & (NR_IRQS - 1);
 224         if (cpu_irq > 14) {  /* 14 irq levels on the sparc */
 225                 printk("Trying to free bogus IRQ %d\n", irq);
 226                 return;
 227         }
 228
 229         spin_lock_irqsave(&irq_action_lock, flags);
 230
 231         actionp = &sparc_irq[cpu_irq].action;
 232         action = *actionp;
 233
 234         if (!action->handler) {
 235                 printk("Trying to free free IRQ%d\n",irq);
 236                 goto out_unlock;
 237         }
 238         if (dev_id) {
 239                 for (; action; action = action->next) {
 240                         if (action->dev_id == dev_id)
 241                                 break;
 242                         actionp = &action->next;
 243                 }
 244                 if (!action) {
 245                         printk("Trying to free free shared IRQ%d\n",irq);
 246                         goto out_unlock;
 247                 }
 248         } else if (action->flags & IRQF_SHARED) {
 249                 printk("Trying to free shared IRQ%d with NULL device ID\n", irq);
 250                 goto out_unlock;
 251         }
 252         if (action->flags & SA_STATIC_ALLOC)
 253         {
 254                 /* This interrupt is marked as specially allocated
 255                  * so it is a bad idea to free it.
 256                  */
 257                 printk("Attempt to free statically allocated IRQ%d (%s)\n",
 258                        irq, action->name);
 259                 goto out_unlock;
 260         }
 261
 262         *actionp = action->next;
 263
 264         spin_unlock_irqrestore(&irq_action_lock, flags);
 265
 266         synchronize_irq(irq);
 267
 268         spin_lock_irqsave(&irq_action_lock, flags);
 269
 270         kfree(action);
 271
 272         if (!sparc_irq[cpu_irq].action)
 273                 __disable_irq(irq);
 274
 275 out_unlock:
 276         spin_unlock_irqrestore(&irq_action_lock, flags);
 277 }
 278
 279 EXPORT_SYMBOL(free_irq);
 280
 281 /*
 282  * This is called when we want to synchronize with
 283  * interrupts. We may for example tell a device to
 284  * stop sending interrupts: but to make sure there
 285  * are no interrupts that are executing on another
 286  * CPU we need to call this function.
 287  */
 288 #ifdef CONFIG_SMP
 289 void synchronize_irq(unsigned int irq)
 290 {
 291         unsigned int cpu_irq;
 292
 293         cpu_irq = irq & (NR_IRQS - 1);
 294         while (sparc_irq[cpu_irq].flags & SPARC_IRQ_INPROGRESS)
 295                 cpu_relax();
 296 }
 297 #endif /* SMP */
 298
 299 void unexpected_irq(int irq, void *dev_id, struct pt_regs * regs)
 300 {
 301         int i;
 302         struct irqaction * action;
 303         unsigned int cpu_irq;
 304
 305         cpu_irq = irq & (NR_IRQS - 1);
 306         action = sparc_irq[cpu_irq].action;
 307
 308         printk("IO device interrupt, irq = %d\n", irq);
 309         printk("PC = %08lx NPC = %08lx FP=%08lx\n", regs->pc,
 310                     regs->npc, regs->u_regs[14]);
 311         if (action) {
 312                 printk("Expecting: ");
 313                 for (i = 0; i < 16; i++)
 314                         if (action->handler)
 315                                 printk("[%s:%d:0x%x] ", action->name,
 316                                        (int) i, (unsigned int) action->handler);
 317         }
 318         printk("AIEEE\n");
 319         panic("bogus interrupt received");
 320 }
 321
 322 void handler_irq(int irq, struct pt_regs * regs)
 323 {
 324         struct pt_regs *old_regs;
 325         struct irqaction * action;
 326         int cpu = smp_processor_id();
 327 #ifdef CONFIG_SMP
 328         extern void smp4m_irq_rotate(int cpu);
 329 #endif
 330
 331         old_regs = set_irq_regs(regs);
 332         irq_enter();
 333         disable_pil_irq(irq);
 334 #ifdef CONFIG_SMP
 335         /* Only rotate on lower priority IRQs (scsi, ethernet, etc.). */
 336         if((sparc_cpu_model==sun4m) && (irq < 10))
 337                 smp4m_irq_rotate(cpu);
 338 #endif
 339         action = sparc_irq[irq].action;
 340         sparc_irq[irq].flags |= SPARC_IRQ_INPROGRESS;
 341         kstat_cpu(cpu).irqs[irq]++;
 342         do {
 343                 if (!action || !action->handler)
 344                         unexpected_irq(irq, NULL, regs);
 345                 action->handler(irq, action->dev_id);
 346                 action = action->next;
 347         } while (action);
 348         sparc_irq[irq].flags &= ~SPARC_IRQ_INPROGRESS;
 349         enable_pil_irq(irq);
 350         irq_exit();
 351         set_irq_regs(old_regs);
 352 }
 353
 354 #if defined(CONFIG_BLK_DEV_FD) || defined(CONFIG_BLK_DEV_FD_MODULE)
 355
 356 /* Fast IRQs on the Sparc can only have one routine attached to them,
 357  * thus no sharing possible.
 358  */
 359 static int request_fast_irq(unsigned int irq,
 360                             void (*handler)(void),
 361                             unsigned long irqflags, const char *devname)
 362 {
 363         struct irqaction *action;
 364         unsigned long flags;
 365         unsigned int cpu_irq;
 366         int ret;
 367 #ifdef CONFIG_SMP
 368         struct tt_entry *trap_table;
 369         extern struct tt_entry trapbase_cpu1, trapbase_cpu2, trapbase_cpu3;
 370 #endif
 371
 372         cpu_irq = irq & (NR_IRQS - 1);
 373         if(cpu_irq > 14) {
 374                 ret = -EINVAL;
 375                 goto out;
 376         }
 377         if(!handler) {
 378                 ret = -EINVAL;
 379                 goto out;
 380         }
 381
 382         spin_lock_irqsave(&irq_action_lock, flags);
 383
 384         action = sparc_irq[cpu_irq].action;
 385         if(action) {
 386                 if(action->flags & IRQF_SHARED)
 387                         panic("Trying to register fast irq when already shared.\n");
 388                 if(irqflags & IRQF_SHARED)
 389                         panic("Trying to register fast irq as shared.\n");
 390
 391                 /* Anyway, someone already owns it so cannot be made fast. */
 392                 printk("request_fast_irq: Trying to register yet already owned.\n");
 393                 ret = -EBUSY;
 394                 goto out_unlock;
 395         }
 396
 397         /* If this is flagged as statically allocated then we use our
 398          * private struct which is never freed.
 399          */
 400         if (irqflags & SA_STATIC_ALLOC) {
 401             if (static_irq_count < MAX_STATIC_ALLOC)
 402                 action = &static_irqaction[static_irq_count++];
 403             else
 404                 printk("Fast IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n",
 405                        irq, devname);
 406         }
 407
 408         if (action == NULL)
 409             action = kmalloc(sizeof(struct irqaction),
 410                                                  GFP_ATOMIC);
 411
 412         if (!action) {
 413                 ret = -ENOMEM;
 414                 goto out_unlock;
 415         }
 416
 417         /* Dork with trap table if we get this far. */
 418 #define INSTANTIATE(table) \
 419         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_one = SPARC_RD_PSR_L0; \
 420         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two = \
 421                 SPARC_BRANCH((unsigned long) handler, \
 422                              (unsigned long) &table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two);\
 423         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_three = SPARC_RD_WIM_L3; \
 424         table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_four = SPARC_NOP;
 425
 426         INSTANTIATE(sparc_ttable)
 427 #ifdef CONFIG_SMP
 428         trap_table = &trapbase_cpu1; INSTANTIATE(trap_table)
 429         trap_table = &trapbase_cpu2; INSTANTIATE(trap_table)
 430         trap_table = &trapbase_cpu3; INSTANTIATE(trap_table)
 431 #endif
 432 #undef INSTANTIATE
 433         /*
 434          * XXX Correct thing whould be to flush only I- and D-cache lines
 435          * which contain the handler in question. But as of time of the
 436          * writing we have no CPU-neutral interface to fine-grained flushes.
 437          */
 438         flush_cache_all();
 439
 440         action->flags = irqflags;
 441         cpus_clear(action->mask);
 442         action->name = devname;
 443         action->dev_id = NULL;
 444         action->next = NULL;
 445
 446         sparc_irq[cpu_irq].action = action;
 447
 448         __enable_irq(irq);
 449
 450         ret = 0;
 451 out_unlock:
 452         spin_unlock_irqrestore(&irq_action_lock, flags);
 453 out:
 454         return ret;
 455 }
 456
 457 /* These variables are used to access state from the assembler
 458  * interrupt handler, floppy_hardint, so we cannot put these in
 459  * the floppy driver image because that would not work in the
 460  * modular case.
 461  */
 462 volatile unsigned char *fdc_status;
 463 EXPORT_SYMBOL(fdc_status);
 464
 465 char *pdma_vaddr;
 466 EXPORT_SYMBOL(pdma_vaddr);
 467
 468 unsigned long pdma_size;
 469 EXPORT_SYMBOL(pdma_size);
 470
 471 volatile int doing_pdma;
 472 EXPORT_SYMBOL(doing_pdma);
 473
 474 char *pdma_base;
 475 EXPORT_SYMBOL(pdma_base);
 476
 477 unsigned long pdma_areasize;
 478 EXPORT_SYMBOL(pdma_areasize);
 479
 480 extern void floppy_hardint(void);
 481
 482 static irqreturn_t (*floppy_irq_handler)(int irq, void *dev_id);
 483
 484 void sparc_floppy_irq(int irq, void *dev_id, struct pt_regs *regs)
 485 {
 486         struct pt_regs *old_regs;
 487         int cpu = smp_processor_id();
 488
 489         old_regs = set_irq_regs(regs);
 490         disable_pil_irq(irq);
 491         irq_enter();
 492         kstat_cpu(cpu).irqs[irq]++;
 493         floppy_irq_handler(irq, dev_id);
 494         irq_exit();
 495         enable_pil_irq(irq);
 496         set_irq_regs(old_regs);
 497         // XXX Eek, it's totally changed with preempt_count() and such
 498         // if (softirq_pending(cpu))
 499         //      do_softirq();
 500 }
 501
 502 int sparc_floppy_request_irq(int irq, unsigned long flags,
 503                              irqreturn_t (*irq_handler)(int irq, void *))
 504 {
 505         floppy_irq_handler = irq_handler;
 506         return request_fast_irq(irq, floppy_hardint, flags, "floppy");
 507 }
 508 EXPORT_SYMBOL(sparc_floppy_request_irq);
 509
 510 #endif
 511
 512 int request_irq(unsigned int irq,
 513                 irq_handler_t handler,
 514                 unsigned long irqflags, const char * devname, void *dev_id)
 515 {
 516         struct irqaction * action, **actionp;
 517         unsigned long flags;
 518         unsigned int cpu_irq;
 519         int ret;
 520
 521         if (sparc_cpu_model == sun4d) {
 522                 extern int sun4d_request_irq(unsigned int,
 523                                              irq_handler_t ,
 524                                              unsigned long, const char *, void *);
 525                 return sun4d_request_irq(irq, handler, irqflags, devname, dev_id);
 526         }
 527         cpu_irq = irq & (NR_IRQS - 1);
 528         if(cpu_irq > 14) {
 529                 ret = -EINVAL;
 530                 goto out;
 531         }
 532         if (!handler) {
 533                 ret = -EINVAL;
 534                 goto out;
 535         }
 536
 537         spin_lock_irqsave(&irq_action_lock, flags);
 538
 539         actionp = &sparc_irq[cpu_irq].action;
 540         action = *actionp;
 541         if (action) {
 542                 if (!(action->flags & IRQF_SHARED) || !(irqflags & IRQF_SHARED)) {
 543                         ret = -EBUSY;
 544                         goto out_unlock;
 545                 }
 546                 if ((action->flags & IRQF_DISABLED) != (irqflags & IRQF_DISABLED)) {
 547                         printk("Attempt to mix fast and slow interrupts on IRQ%d denied\n", irq);
 548                         ret = -EBUSY;
 549                         goto out_unlock;
 550                 }
 551                 for ( ; action; action = *actionp)
 552                         actionp = &action->next;
 553         }
 554
 555         /* If this is flagged as statically allocated then we use our
 556          * private struct which is never freed.
 557          */
 558         if (irqflags & SA_STATIC_ALLOC) {
 559                 if (static_irq_count < MAX_STATIC_ALLOC)
 560                         action = &static_irqaction[static_irq_count++];
 561                 else
 562                         printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n", irq, devname);
 563         }
 564
 565         if (action == NULL)
 566                 action = kmalloc(sizeof(struct irqaction),
 567                                                      GFP_ATOMIC);
 568
 569         if (!action) {
 570                 ret = -ENOMEM;
 571                 goto out_unlock;
 572         }
 573
 574         action->handler = handler;
 575         action->flags = irqflags;
 576         cpus_clear(action->mask);
 577         action->name = devname;
 578         action->next = NULL;
 579         action->dev_id = dev_id;
 580
 581         *actionp = action;
 582
 583         __enable_irq(irq);
 584
 585         ret = 0;
 586 out_unlock:
 587         spin_unlock_irqrestore(&irq_action_lock, flags);
 588 out:
 589         return ret;
 590 }
 591
 592 EXPORT_SYMBOL(request_irq);
 593
 594 void disable_irq_nosync(unsigned int irq)
 595 {
 596         return __disable_irq(irq);
 597 }
 598 EXPORT_SYMBOL(disable_irq_nosync);
 599
 600 void disable_irq(unsigned int irq)
 601 {
 602         return __disable_irq(irq);
 603 }
 604 EXPORT_SYMBOL(disable_irq);
 605
 606 void enable_irq(unsigned int irq)
 607 {
 608         return __enable_irq(irq);
 609 }
 610
 611 EXPORT_SYMBOL(enable_irq);
 612
 613 /* We really don't need these at all on the Sparc.  We only have
 614  * stubs here because they are exported to modules.
 615  */
 616 unsigned long probe_irq_on(void)
 617 {
 618         return 0;
 619 }
 620
 621 EXPORT_SYMBOL(probe_irq_on);
 622
 623 int probe_irq_off(unsigned long mask)
 624 {
 625         return 0;
 626 }
 627
 628 EXPORT_SYMBOL(probe_irq_off);
 629
 630 /* djhr
 631  * This could probably be made indirect too and assigned in the CPU
 632  * bits of the code. That would be much nicer I think and would also
 633  * fit in with the idea of being able to tune your kernel for your machine
 634  * by removing unrequired machine and device support.
 635  *
 636  */
 637
 638 void __init init_IRQ(void)
 639 {
 640         extern void sun4c_init_IRQ( void );
 641         extern void sun4m_init_IRQ( void );
 642         extern void sun4d_init_IRQ( void );
 643
 644         switch(sparc_cpu_model) {
 645         case sun4c:
 646         case sun4:
 647                 sun4c_init_IRQ();
 648                 break;
 649
 650         case sun4m:
 651 #ifdef CONFIG_PCI
 652                 pcic_probe();
 653                 if (pcic_present()) {
 654                         sun4m_pci_init_IRQ();
 655                         break;
 656                 }
 657 #endif
 658                 sun4m_init_IRQ();
 659                 break;
 660
 661         case sun4d:
 662                 sun4d_init_IRQ();
 663                 break;
 664
 665         default:
 666                 prom_printf("Cannot initialize IRQs on this Sun machine...");
 667                 break;
 668         }
 669         btfixup();
 670 }
 671
 672 void init_irq_proc(void)
 673 {
 674         /* For now, nothing... */
 675 }