/*
   * Copyright 2009 Red Hat Inc.
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
   * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
   * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   * OTHER DEALINGS IN THE SOFTWARE.
   *
   * Authors: Dave Airlie
   */

  #ifndef DRM_FIXED_H
  #define DRM_FIXED_H

  typedef union dfixed {

  	u32 full;
  } fixed20_12;

  #define dfixed_const(A) (u32)(((A) << 12))/*  + ((B + 0.000122)*4096)) */
  #define dfixed_const_half(A) (u32)(((A) << 12) + 2048)
  #define dfixed_const_666(A) (u32)(((A) << 12) + 2731)
  #define dfixed_const_8(A) (u32)(((A) << 12) + 3277)
  #define dfixed_mul(A, B) ((u64)((u64)(A).full * (B).full + 2048) >> 12)
  #define dfixed_init(A) { .full = dfixed_const((A)) }
  #define dfixed_init_half(A) { .full = dfixed_const_half((A)) }
  #define dfixed_trunc(A) ((A).full >> 12)

  static inline u32 dfixed_floor(fixed20_12 A)

  {

  	u32 non_frac = dfixed_trunc(A);

  	return dfixed_const(non_frac);

  }

  static inline u32 dfixed_ceil(fixed20_12 A)

  {

  	u32 non_frac = dfixed_trunc(A);

  	if (A.full > dfixed_const(non_frac))
  		return dfixed_const(non_frac + 1);

  	else

  		return dfixed_const(non_frac);

  }

  static inline u32 dfixed_div(fixed20_12 A, fixed20_12 B)

  {
  	u64 tmp = ((u64)A.full << 13);
  
  	do_div(tmp, B.full);
  	tmp += 1;
  	tmp /= 2;
  	return lower_32_bits(tmp);
  }
  #endif