arch/ppc/kernel/irq.c

   1 /*
   2  *  arch/ppc/kernel/irq.c
   3  *
   4  *  Derived from arch/i386/kernel/irq.c
   5  *    Copyright (C) 1992 Linus Torvalds
   6  *  Adapted from arch/i386 by Gary Thomas
   7  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   8  *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
   9  *    Copyright (C) 1996-2001 Cort Dougan
  10  *  Adapted for Power Macintosh by Paul Mackerras
  11  *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
  12  *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
  13  *
  14  * This file contains the code used by various IRQ handling routines:
  15  * asking for different IRQ's should be done through these routines
  16  * instead of just grabbing them. Thus setups with different IRQ numbers
  17  * shouldn't result in any weird surprises, and installing new handlers
  18  * should be easier.
  19  *
  20  * The MPC8xx has an interrupt mask in the SIU.  If a bit is set, the
  21  * interrupt is _enabled_.  As expected, IRQ0 is bit 0 in the 32-bit
  22  * mask register (of which only 16 are defined), hence the weird shifting
  23  * and complement of the cached_irq_mask.  I want to be able to stuff
  24  * this right into the SIU SMASK register.
  25  * Many of the prep/chrp functions are conditional compiled on CONFIG_8xx
  26  * to reduce code space and undefined function references.
  27  */
  28
  29 #include <linux/errno.h>
  30 #include <linux/module.h>
  31 #include <linux/threads.h>
  32 #include <linux/kernel_stat.h>
  33 #include <linux/signal.h>
  34 #include <linux/sched.h>
  35 #include <linux/ptrace.h>
  36 #include <linux/ioport.h>
  37 #include <linux/interrupt.h>
  38 #include <linux/timex.h>
  39 #include <linux/config.h>
  40 #include <linux/init.h>
  41 #include <linux/slab.h>
  42 #include <linux/pci.h>
  43 #include <linux/delay.h>
  44 #include <linux/irq.h>
  45 #include <linux/proc_fs.h>
  46 #include <linux/random.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/cpumask.h>
  49 #include <linux/profile.h>
  50 #include <linux/bitops.h>
  51
  52 #include <asm/uaccess.h>
  53 #include <asm/system.h>
  54 #include <asm/io.h>
  55 #include <asm/pgtable.h>
  56 #include <asm/irq.h>
  57 #include <asm/cache.h>
  58 #include <asm/prom.h>
  59 #include <asm/ptrace.h>
  60 #include <asm/machdep.h>
  61
  62 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
  63
  64 extern atomic_t ipi_recv;
  65 extern atomic_t ipi_sent;
  66
  67 #define MAXCOUNT 10000000
  68
  69 int ppc_spurious_interrupts = 0;
  70 struct irqaction *ppc_irq_action[NR_IRQS];
  71 unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
  72 unsigned long ppc_lost_interrupts[NR_MASK_WORDS];
  73 atomic_t ppc_n_lost_interrupts;
  74
  75 #ifdef CONFIG_TAU_INT
  76 extern int tau_initialized;
  77 extern int tau_interrupts(int);
  78 #endif
  79
  80 int show_interrupts(struct seq_file *p, void *v)
  81 {
  82         int i = *(loff_t *) v, j;
  83         struct irqaction * action;
  84         unsigned long flags;
  85
  86         if (i == 0) {
  87                 seq_puts(p, "           ");
  88                 for (j=0; j<NR_CPUS; j++)
  89                         if (cpu_online(j))
  90                                 seq_printf(p, "CPU%d       ", j);
  91                 seq_putc(p, '\n');
  92         }
  93
  94         if (i < NR_IRQS) {
  95                 spin_lock_irqsave(&irq_desc[i].lock, flags);
  96                 action = irq_desc[i].action;
  97                 if ( !action || !action->handler )
  98                         goto skip;
  99                 seq_printf(p, "%3d: ", i);
 100 #ifdef CONFIG_SMP
 101                 for (j = 0; j < NR_CPUS; j++)
 102                         if (cpu_online(j))
 103                                 seq_printf(p, "%10u ",
 104                                            kstat_cpu(j).irqs[i]);
 105 #else
 106                 seq_printf(p, "%10u ", kstat_irqs(i));
 107 #endif /* CONFIG_SMP */
 108                 if (irq_desc[i].handler)
 109                         seq_printf(p, " %s ", irq_desc[i].handler->typename);
 110                 else
 111                         seq_puts(p, "  None      ");
 112                 seq_printf(p, "%s", (irq_desc[i].status & IRQ_LEVEL) ? "Level " : "Edge  ");
 113                 seq_printf(p, "    %s", action->name);
 114                 for (action = action->next; action; action = action->next)
 115                         seq_printf(p, ", %s", action->name);
 116                 seq_putc(p, '\n');
 117 skip:
 118                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
 119         } else if (i == NR_IRQS) {
 120 #ifdef CONFIG_TAU_INT
 121                 if (tau_initialized){
 122                         seq_puts(p, "TAU: ");
 123                         for (j = 0; j < NR_CPUS; j++)
 124                                 if (cpu_online(j))
 125                                         seq_printf(p, "%10u ", tau_interrupts(j));
 126                         seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
 127                 }
 128 #endif
 129 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
 130                 /* should this be per processor send/receive? */
 131                 seq_printf(p, "IPI (recv/sent): %10u/%u\n",
 132                                 atomic_read(&ipi_recv), atomic_read(&ipi_sent));
 133 #endif
 134                 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
 135         }
 136         return 0;
 137 }
 138
 139 void do_IRQ(struct pt_regs *regs)
 140 {
 141         int irq, first = 1;
 142         irq_enter();
 143
 144         /*
 145          * Every platform is required to implement ppc_md.get_irq.
 146          * This function will either return an irq number or -1 to
 147          * indicate there are no more pending.  But the first time
 148          * through the loop this means there wasn't and IRQ pending.
 149          * The value -2 is for buggy hardware and means that this IRQ
 150          * has already been handled. -- Tom
 151          */
 152         while ((irq = ppc_md.get_irq(regs)) >= 0) {
 153                 __do_IRQ(irq, regs);
 154                 first = 0;
 155         }
 156         if (irq != -2 && first)
 157                 /* That's not SMP safe ... but who cares ? */
 158                 ppc_spurious_interrupts++;
 159         irq_exit();
 160 }
 161
 162 void __init init_IRQ(void)
 163 {
 164         ppc_md.init_IRQ();
 165 }