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/irq.h"
  13 #include "linux/kernel_stat.h"
  14 #include "linux/interrupt.h"
  15 #include "linux/random.h"
  16 #include "linux/slab.h"
  17 #include "linux/file.h"
  18 #include "linux/proc_fs.h"
  19 #include "linux/init.h"
  20 #include "linux/seq_file.h"
  21 #include "linux/profile.h"
  22 #include "linux/hardirq.h"
  23 #include "asm/irq.h"
  24 #include "asm/hw_irq.h"
  25 #include "asm/atomic.h"
  26 #include "asm/signal.h"
  27 #include "asm/system.h"
  28 #include "asm/errno.h"
  29 #include "asm/uaccess.h"
  30 #include "user_util.h"
  31 #include "kern_util.h"
  32 #include "irq_user.h"
  33 #include "irq_kern.h"
  34 #include "os.h"
  35
  36 /*
  37  * Generic, controller-independent functions:
  38  */
  39
  40 int show_interrupts(struct seq_file *p, void *v)
  41 {
  42         int i = *(loff_t *) v, j;
  43         struct irqaction * action;
  44         unsigned long flags;
  45
  46         if (i == 0) {
  47                 seq_printf(p, "           ");
  48                 for_each_online_cpu(j)
  49                         seq_printf(p, "CPU%d       ",j);
  50                 seq_putc(p, '\n');
  51         }
  52
  53         if (i < NR_IRQS) {
  54                 spin_lock_irqsave(&irq_desc[i].lock, flags);
  55                 action = irq_desc[i].action;
  56                 if (!action)
  57                         goto skip;
  58                 seq_printf(p, "%3d: ",i);
  59 #ifndef CONFIG_SMP
  60                 seq_printf(p, "%10u ", kstat_irqs(i));
  61 #else
  62                 for_each_online_cpu(j)
  63                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
  64 #endif
  65                 seq_printf(p, " %14s", irq_desc[i].handler->typename);
  66                 seq_printf(p, "  %s", action->name);
  67
  68                 for (action=action->next; action; action = action->next)
  69                         seq_printf(p, ", %s", action->name);
  70
  71                 seq_putc(p, '\n');
  72 skip:
  73                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
  74         } else if (i == NR_IRQS) {
  75                 seq_putc(p, '\n');
  76         }
  77
  78         return 0;
  79 }
  80
  81 /*
  82  * do_IRQ handles all normal device IRQ's (the special
  83  * SMP cross-CPU interrupts have their own specific
  84  * handlers).
  85  */
  86 unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
  87 {
  88        irq_enter();
  89        __do_IRQ(irq, (struct pt_regs *) regs);
  90        irq_exit();
  91        return 1;
  92 }
  93
  94 int um_request_irq(unsigned int irq, int fd, int type,
  95                    irqreturn_t (*handler)(int, void *, struct pt_regs *),
  96                    unsigned long irqflags, const char * devname,
  97                    void *dev_id)
  98 {
  99         int err;
 100
 101         err = request_irq(irq, handler, irqflags, devname, dev_id);
 102         if(err)
 103                 return(err);
 104
 105         if(fd != -1)
 106                 err = activate_fd(irq, fd, type, dev_id);
 107         return(err);
 108 }
 109 EXPORT_SYMBOL(um_request_irq);
 110 EXPORT_SYMBOL(reactivate_fd);
 111
 112 static DEFINE_SPINLOCK(irq_spinlock);
 113
 114 unsigned long irq_lock(void)
 115 {
 116         unsigned long flags;
 117
 118         spin_lock_irqsave(&irq_spinlock, flags);
 119         return(flags);
 120 }
 121
 122 void irq_unlock(unsigned long flags)
 123 {
 124         spin_unlock_irqrestore(&irq_spinlock, flags);
 125 }
 126
 127 /* hw_interrupt_type must define (startup || enable) &&
 128  * (shutdown || disable) && end */
 129 static void dummy(unsigned int irq)
 130 {
 131 }
 132
 133 /* This is used for everything else than the timer. */
 134 static struct hw_interrupt_type normal_irq_type = {
 135         .typename = "SIGIO",
 136         .release = free_irq_by_irq_and_dev,
 137         .disable = dummy,
 138         .enable = dummy,
 139         .ack = dummy,
 140         .end = dummy
 141 };
 142
 143 static struct hw_interrupt_type SIGVTALRM_irq_type = {
 144         .typename = "SIGVTALRM",
 145         .release = free_irq_by_irq_and_dev,
 146         .shutdown = dummy, /* never called */
 147         .disable = dummy,
 148         .enable = dummy,
 149         .ack = dummy,
 150         .end = dummy
 151 };
 152
 153 void __init init_IRQ(void)
 154 {
 155         int i;
 156
 157         irq_desc[TIMER_IRQ].status = IRQ_DISABLED;
 158         irq_desc[TIMER_IRQ].action = NULL;
 159         irq_desc[TIMER_IRQ].depth = 1;
 160         irq_desc[TIMER_IRQ].handler = &SIGVTALRM_irq_type;
 161         enable_irq(TIMER_IRQ);
 162         for(i=1;i<NR_IRQS;i++){
 163                 irq_desc[i].status = IRQ_DISABLED;
 164                 irq_desc[i].action = NULL;
 165                 irq_desc[i].depth = 1;
 166                 irq_desc[i].handler = &normal_irq_type;
 167                 enable_irq(i);
 168         }
 169 }
 170
 171 int init_aio_irq(int irq, char *name, irqreturn_t (*handler)(int, void *,
 172                                                              struct pt_regs *))
 173 {
 174         int fds[2], err;
 175
 176         err = os_pipe(fds, 1, 1);
 177         if(err){
 178                 printk("init_aio_irq - os_pipe failed, err = %d\n", -err);
 179                 goto out;
 180         }
 181
 182         err = um_request_irq(irq, fds[0], IRQ_READ, handler,
 183                              SA_INTERRUPT | SA_SAMPLE_RANDOM, name,
 184                              (void *) (long) fds[0]);
 185         if(err){
 186                 printk("init_aio_irq - : um_request_irq failed, err = %d\n",
 187                        err);
 188                 goto out_close;
 189         }
 190
 191         err = fds[1];
 192         goto out;
 193
 194  out_close:
 195         os_close_file(fds[0]);
 196         os_close_file(fds[1]);
 197  out:
 198         return(err);
 199 }