/*
   * IOP Coprocessor-6 access handler
   * Copyright (c) 2006, Intel Corporation.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms and conditions of the GNU General Public License,
   * version 2, as published by the Free Software Foundation.
   *
   * This program is distributed in the hope it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
   * Place - Suite 330, Boston, MA 02111-1307 USA.
   *
   */
  #include <linux/init.h>
  #include <asm/traps.h>
  #include <asm/ptrace.h>
  
  static int cp6_trap(struct pt_regs *regs, unsigned int instr)
  {
  	u32 temp;
  
          /* enable cp6 access */
          asm volatile (
  		"mrc	p15, 0, %0, c15, c1, 0
  \t"
  		"orr	%0, %0, #(1 << 6)
  \t"
  		"mcr	p15, 0, %0, c15, c1, 0
  \t"
  		: "=r"(temp));
  
  	return 0;
  }
  
  /* permit kernel space cp6 access
   * deny user space cp6 access
   */
  static struct undef_hook cp6_hook = {
  	.instr_mask     = 0x0f000ff0,
  	.instr_val      = 0x0e000610,
  	.cpsr_mask      = MODE_MASK,
  	.cpsr_val       = SVC_MODE,
  	.fn             = cp6_trap,
  };
  
  void __init iop_init_cp6_handler(void)
  {
  	register_undef_hook(&cp6_hook);
  }