arch/arm/kernel/iwmmxt-notifier.c

   1 /*
   2  *  linux/arch/arm/kernel/iwmmxt-notifier.c
   3  *
   4  *  XScale iWMMXt (Concan) context switching and handling
   5  *
   6  *  Initial code:
   7  *  Copyright (c) 2003, Intel Corporation
   8  *
   9  *  Full lazy switching support, optimizations and more, by Nicolas Pitre
  10  *  Copyright (c) 2003-2004, MontaVista Software, Inc.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/config.h>
  19 #include <linux/types.h>
  20 #include <linux/kernel.h>
  21 #include <linux/signal.h>
  22 #include <linux/sched.h>
  23 #include <linux/init.h>
  24 #include <asm/thread_notify.h>
  25 #include <asm/io.h>
  26
  27 static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t)
  28 {
  29         struct thread_info *thread = t;
  30
  31         switch (cmd) {
  32         case THREAD_NOTIFY_FLUSH:
  33                 /*
  34                  * flush_thread() zeroes thread->fpstate, so no need
  35                  * to do anything here.
  36                  *
  37                  * FALLTHROUGH: Ensure we don't try to overwrite our newly
  38                  * initialised state information on the first fault.
  39                  */
  40
  41         case THREAD_NOTIFY_RELEASE:
  42                 iwmmxt_task_release(thread);
  43                 break;
  44
  45         case THREAD_NOTIFY_SWITCH:
  46                 iwmmxt_task_switch(thread);
  47                 break;
  48         }
  49
  50         return NOTIFY_DONE;
  51 }
  52
  53 static struct notifier_block iwmmxt_notifier_block = {
  54         .notifier_call  = iwmmxt_do,
  55 };
  56
  57 static int __init iwmmxt_init(void)
  58 {
  59         thread_register_notifier(&iwmmxt_notifier_block);
  60
  61         return 0;
  62 }
  63
  64 late_initcall(iwmmxt_init);