arch/mips/cavium-octeon/cpu.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2009 Wind River Systems,
   7  *   written by Ralf Baechle <ralf@linux-mips.org>
   8  */
   9 #include <linux/init.h>
  10 #include <linux/irqflags.h>
  11 #include <linux/notifier.h>
  12 #include <linux/prefetch.h>
  13 #include <linux/sched.h>
  14
  15 #include <asm/cop2.h>
  16 #include <asm/current.h>
  17 #include <asm/mipsregs.h>
  18 #include <asm/page.h>
  19 #include <asm/octeon/octeon.h>
  20
  21 static int cnmips_cu2_call(struct notifier_block *nfb, unsigned long action,
  22         void *data)
  23 {
  24         unsigned long flags;
  25         unsigned int status;
  26
  27         switch (action) {
  28         case CU2_EXCEPTION:
  29                 prefetch(&current->thread.cp2);
  30                 local_irq_save(flags);
  31                 KSTK_STATUS(current) |= ST0_CU2;
  32                 status = read_c0_status();
  33                 write_c0_status(status | ST0_CU2);
  34                 octeon_cop2_restore(&(current->thread.cp2));
  35                 write_c0_status(status & ~ST0_CU2);
  36                 local_irq_restore(flags);
  37
  38                 return NOTIFY_BAD;      /* Don't call default notifier */
  39         }
  40
  41         return NOTIFY_OK;               /* Let default notifier send signals */
  42 }
  43
  44 static struct notifier_block cnmips_cu2_notifier = {
  45         .notifier_call = cnmips_cu2_call,
  46 };
  47
  48 static int cnmips_cu2_setup(void)
  49 {
  50         return register_cu2_notifier(&cnmips_cu2_notifier);
  51 }
  52 early_initcall(cnmips_cu2_setup);