/*
 * Copyright 2015 Advanced Micro Devices, 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: AMD
 *
 */

#ifndef BW_FIXED_H_
#define BW_FIXED_H_

#define BW_FIXED_BITS_PER_FRACTIONAL_PART 24

#define BW_FIXED_GET_INTEGER_PART(x) ((x) >> BW_FIXED_BITS_PER_FRACTIONAL_PART)
struct bw_fixed {
	int64_t value;
};

#define BW_FIXED_MIN_I32 \
	(int64_t)(-(1LL << (63 - BW_FIXED_BITS_PER_FRACTIONAL_PART)))

#define BW_FIXED_MAX_I32 \
	(int64_t)((1ULL << (63 - BW_FIXED_BITS_PER_FRACTIONAL_PART)) - 1)

static inline struct bw_fixed bw_min2(const struct bw_fixed arg1,
				      const struct bw_fixed arg2)
{
	return (arg1.value <= arg2.value) ? arg1 : arg2;
}

static inline struct bw_fixed bw_max2(const struct bw_fixed arg1,
				      const struct bw_fixed arg2)
{
	return (arg2.value <= arg1.value) ? arg1 : arg2;
}

static inline struct bw_fixed bw_min3(struct bw_fixed v1,
				      struct bw_fixed v2,
				      struct bw_fixed v3)
{
	return bw_min2(bw_min2(v1, v2), v3);
}

static inline struct bw_fixed bw_max3(struct bw_fixed v1,
				      struct bw_fixed v2,
				      struct bw_fixed v3)
{
	return bw_max2(bw_max2(v1, v2), v3);
}

struct bw_fixed bw_int_to_fixed_nonconst(int64_t value);
static inline struct bw_fixed bw_int_to_fixed(int64_t value)
{
	if (__builtin_constant_p(value)) {
		struct bw_fixed res;
		BUILD_BUG_ON(value > BW_FIXED_MAX_I32 || value < BW_FIXED_MIN_I32);
		res.value = value << BW_FIXED_BITS_PER_FRACTIONAL_PART;
		return res;
	} else
		return bw_int_to_fixed_nonconst(value);
}

static inline int32_t bw_fixed_to_int(struct bw_fixed value)
{
	return BW_FIXED_GET_INTEGER_PART(value.value);
}

struct bw_fixed bw_frc_to_fixed(int64_t num, int64_t denum);

static inline struct bw_fixed fixed31_32_to_bw_fixed(int64_t raw)
{
	struct bw_fixed result = { 0 };

	if (raw < 0) {
		raw = -raw;
		result.value = -(raw >> (32 - BW_FIXED_BITS_PER_FRACTIONAL_PART));
	} else {
		result.value = raw >> (32 - BW_FIXED_BITS_PER_FRACTIONAL_PART);
	}

	return result;
}

static inline struct bw_fixed bw_add(const struct bw_fixed arg1,
				     const struct bw_fixed arg2)
{
	struct bw_fixed res;

	res.value = arg1.value + arg2.value;

	return res;
}

static inline struct bw_fixed bw_sub(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	struct bw_fixed res;

	res.value = arg1.value - arg2.value;

	return res;
}

struct bw_fixed bw_mul(const struct bw_fixed arg1, const struct bw_fixed arg2);
static inline struct bw_fixed bw_div(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	return bw_frc_to_fixed(arg1.value, arg2.value);
}

static inline struct bw_fixed bw_mod(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	struct bw_fixed res;
	/* XXX: int64_t* -> u64* conversion! */
	div64_u64_rem(arg1.value, arg2.value, (u64 *)&res.value);
	return res;
}

struct bw_fixed bw_floor2(const struct bw_fixed arg, const struct bw_fixed significance);
struct bw_fixed bw_ceil2(const struct bw_fixed arg, const struct bw_fixed significance);

static inline bool bw_equ(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	return arg1.value == arg2.value;
}

static inline bool bw_neq(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	return arg1.value != arg2.value;
}

static inline bool bw_leq(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	return arg1.value <= arg2.value;
}

static inline bool bw_meq(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	return arg1.value >= arg2.value;
}

static inline bool bw_ltn(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	return arg1.value < arg2.value;
}

static inline bool bw_mtn(const struct bw_fixed arg1, const struct bw_fixed arg2)
{
	return arg1.value > arg2.value;
}

#endif //BW_FIXED_H_