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/types.h>
  19 #include <linux/kernel.h>
  20 #include <linux/signal.h>
  21 #include <linux/sched.h>
  22 #include <linux/init.h>
  23 #include <asm/thread_notify.h>
  24 #include <asm/io.h>
  25
  26 static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t)
  27 {
  28         struct thread_info *thread = t;
  29
  30         switch (cmd) {
  31         case THREAD_NOTIFY_FLUSH:
  32                 /*
  33                  * flush_thread() zeroes thread->fpstate, so no need
  34                  * to do anything here.
  35                  *
  36                  * FALLTHROUGH: Ensure we don't try to overwrite our newly
  37                  * initialised state information on the first fault.
  38                  */
  39
  40         case THREAD_NOTIFY_RELEASE:
  41                 iwmmxt_task_release(thread);
  42                 break;
  43
  44         case THREAD_NOTIFY_SWITCH:
  45                 iwmmxt_task_switch(thread);
  46                 break;
  47         }
  48
  49         return NOTIFY_DONE;
  50 }
  51
  52 static struct notifier_block iwmmxt_notifier_block = {
  53         .notifier_call  = iwmmxt_do,
  54 };
  55
  56 static int __init iwmmxt_init(void)
  57 {
  58         thread_register_notifier(&iwmmxt_notifier_block);
  59
  60         return 0;
  61 }
  62
  63 late_initcall(iwmmxt_init);