arch/um/kernel/irq.c

   1 /*
   2  * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  * Derived (i.e. mostly copied) from arch/i386/kernel/irq.c:
   5  *      Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
   6  */
   7
   8 #include "linux/config.h"
   9 #include "linux/kernel.h"
  10 #include "linux/module.h"
  11 #include "linux/smp.h"
  12 #include "linux/kernel_stat.h"
  13 #include "linux/interrupt.h"
  14 #include "linux/random.h"
  15 #include "linux/slab.h"
  16 #include "linux/file.h"
  17 #include "linux/proc_fs.h"
  18 #include "linux/init.h"
  19 #include "linux/seq_file.h"
  20 #include "linux/profile.h"
  21 #include "linux/hardirq.h"
  22 #include "asm/irq.h"
  23 #include "asm/hw_irq.h"
  24 #include "asm/atomic.h"
  25 #include "asm/signal.h"
  26 #include "asm/system.h"
  27 #include "asm/errno.h"
  28 #include "asm/uaccess.h"
  29 #include "user_util.h"
  30 #include "kern_util.h"
  31 #include "irq_user.h"
  32 #include "irq_kern.h"
  33 #include "os.h"
  34
  35 /*
  36  * Generic, controller-independent functions:
  37  */
  38
  39 int show_interrupts(struct seq_file *p, void *v)
  40 {
  41         int i = *(loff_t *) v, j;
  42         struct irqaction * action;
  43         unsigned long flags;
  44
  45         if (i == 0) {
  46                 seq_printf(p, "           ");
  47                 for_each_online_cpu(j)
  48                         seq_printf(p, "CPU%d       ",j);
  49                 seq_putc(p, '\n');
  50         }
  51
  52         if (i < NR_IRQS) {
  53                 spin_lock_irqsave(&irq_desc[i].lock, flags);
  54                 action = irq_desc[i].action;
  55                 if (!action)
  56                         goto skip;
  57                 seq_printf(p, "%3d: ",i);
  58 #ifndef CONFIG_SMP
  59                 seq_printf(p, "%10u ", kstat_irqs(i));
  60 #else
  61                 for_each_online_cpu(j)
  62                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
  63 #endif
  64                 seq_printf(p, " %14s", irq_desc[i].handler->typename);
  65                 seq_printf(p, "  %s", action->name);
  66
  67                 for (action=action->next; action; action = action->next)
  68                         seq_printf(p, ", %s", action->name);
  69
  70                 seq_putc(p, '\n');
  71 skip:
  72                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
  73         } else if (i == NR_IRQS) {
  74                 seq_putc(p, '\n');
  75         }
  76
  77         return 0;
  78 }
  79
  80 /*
  81  * do_IRQ handles all normal device IRQ's (the special
  82  * SMP cross-CPU interrupts have their own specific
  83  * handlers).
  84  */
  85 unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
  86 {
  87        irq_enter();
  88        __do_IRQ(irq, (struct pt_regs *) regs);
  89        irq_exit();
  90        return 1;
  91 }
  92
  93 int um_request_irq(unsigned int irq, int fd, int type,
  94                    irqreturn_t (*handler)(int, void *, struct pt_regs *),
  95                    unsigned long irqflags, const char * devname,
  96                    void *dev_id)
  97 {
  98         int err;
  99
 100         err = request_irq(irq, handler, irqflags, devname, dev_id);
 101         if(err)
 102                 return(err);
 103
 104         if(fd != -1)
 105                 err = activate_fd(irq, fd, type, dev_id);
 106         return(err);
 107 }
 108 EXPORT_SYMBOL(um_request_irq);
 109 EXPORT_SYMBOL(reactivate_fd);
 110
 111 static DEFINE_SPINLOCK(irq_spinlock);
 112
 113 unsigned long irq_lock(void)
 114 {
 115         unsigned long flags;
 116
 117         spin_lock_irqsave(&irq_spinlock, flags);
 118         return(flags);
 119 }
 120
 121 void irq_unlock(unsigned long flags)
 122 {
 123         spin_unlock_irqrestore(&irq_spinlock, flags);
 124 }
 125
 126 /* hw_interrupt_type must define (startup || enable) &&
 127  * (shutdown || disable) && end */
 128 static void dummy(unsigned int irq)
 129 {
 130 }
 131
 132 /* This is used for everything else than the timer. */
 133 static struct hw_interrupt_type normal_irq_type = {
 134         .typename = "SIGIO",
 135         .release = free_irq_by_irq_and_dev,
 136         .disable = dummy,
 137         .enable = dummy,
 138         .ack = dummy,
 139         .end = dummy
 140 };
 141
 142 static struct hw_interrupt_type SIGVTALRM_irq_type = {
 143         .typename = "SIGVTALRM",
 144         .release = free_irq_by_irq_and_dev,
 145         .shutdown = dummy, /* never called */
 146         .disable = dummy,
 147         .enable = dummy,
 148         .ack = dummy,
 149         .end = dummy
 150 };
 151
 152 void __init init_IRQ(void)
 153 {
 154         int i;
 155
 156         irq_desc[TIMER_IRQ].status = IRQ_DISABLED;
 157         irq_desc[TIMER_IRQ].action = NULL;
 158         irq_desc[TIMER_IRQ].depth = 1;
 159         irq_desc[TIMER_IRQ].handler = &SIGVTALRM_irq_type;
 160         enable_irq(TIMER_IRQ);
 161         for(i=1;i<NR_IRQS;i++){
 162                 irq_desc[i].status = IRQ_DISABLED;
 163                 irq_desc[i].action = NULL;
 164                 irq_desc[i].depth = 1;
 165                 irq_desc[i].handler = &normal_irq_type;
 166                 enable_irq(i);
 167         }
 168 }
 169
 170 int init_aio_irq(int irq, char *name, irqreturn_t (*handler)(int, void *,
 171                                                              struct pt_regs *))
 172 {
 173         int fds[2], err;
 174
 175         err = os_pipe(fds, 1, 1);
 176         if(err){
 177                 printk("init_aio_irq - os_pipe failed, err = %d\n", -err);
 178                 goto out;
 179         }
 180
 181         err = um_request_irq(irq, fds[0], IRQ_READ, handler,
 182                              SA_INTERRUPT | SA_SAMPLE_RANDOM, name,
 183                              (void *) (long) fds[0]);
 184         if(err){
 185                 printk("init_aio_irq - : um_request_irq failed, err = %d\n",
 186                        err);
 187                 goto out_close;
 188         }
 189
 190         err = fds[1];
 191         goto out;
 192
 193  out_close:
 194         os_close_file(fds[0]);
 195         os_close_file(fds[1]);
 196  out:
 197         return(err);
 198 }