trig.h

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/* SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright(c) 2016 Intel Corporation. All rights reserved.
 *
 * Author: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
 *         Liam Girdwood <liam.r.girdwood@linux.intel.com>
 *         Keyon Jie <yang.jie@linux.intel.com>
 *         Shriram Shastry <malladi.sastry@linux.intel.com>
 */
 
#ifndef __SOF_MATH_TRIG_H__
#define __SOF_MATH_TRIG_H__
 
#include <stdint.h>
 
#define PI_Q4_28 843314857   /* int32(pi * 2^28) */
#define PI_MUL2_Q4_28 1686629713 /* int32(2 * pi * 2^28) */
#define PI_DIV2_Q3_29 843314857  /* int32(pi / 2 * 2^29) */
#define PI_Q3_29 1686629713  /* int32(pi * 2^29) */
 
#define CORDIC_31B_TABLE_SIZE 31
#define CORDIC_15B_TABLE_SIZE 15
#define CORDIC_30B_ITABLE_SIZE 30
#define CORDIC_16B_ITABLE_SIZE 16
#define CORDIC_31B_ITERATIONS (CORDIC_31B_TABLE_SIZE - 1)
#define CORDIC_16B_ITERATIONS (CORDIC_16B_ITABLE_SIZE - 1)
 
typedef enum {
    EN_32B_CORDIC_SINE,
    EN_32B_CORDIC_COSINE,
    EN_32B_CORDIC_CEXP,
    EN_16B_CORDIC_SINE,
    EN_16B_CORDIC_COSINE,
    EN_16B_CORDIC_CEXP,
} cordic_cfg;
 
struct cordic_cmpx {
    int32_t re;
    int32_t im;
};
 
void cordic_approx(int32_t th_rad_fxp, int32_t a_idx, int32_t *sign, int32_t *b_yn, int32_t *xn,
           int32_t *th_cdc_fxp);
 
int32_t is_scalar_cordic_acos(int32_t realvalue, int numiters_minus_one);
 
int32_t is_scalar_cordic_asin(int32_t realvalue, int numiters_minus_one);
 
void cmpx_cexp(int32_t sign, int32_t b_yn, int32_t xn, cordic_cfg type, struct cordic_cmpx *cexp);
 
static inline int32_t sin_fixed_32b(int32_t th_rad_fxp)
{
    int32_t th_cdc_fxp;
    int32_t sign;
    int32_t b_yn;
    int32_t xn;
    cordic_approx(th_rad_fxp, CORDIC_31B_TABLE_SIZE, &sign, &b_yn, &xn, &th_cdc_fxp);
 
    th_cdc_fxp = sign * b_yn;
    /*convert Q2.30 to Q1.31 format*/
    return sat_int32(Q_SHIFT_LEFT((int64_t)th_cdc_fxp, 30, 31));
}
 
static inline int32_t cos_fixed_32b(int32_t th_rad_fxp)
{
    int32_t th_cdc_fxp;
    int32_t sign;
    int32_t b_yn;
    int32_t xn;
    cordic_approx(th_rad_fxp, CORDIC_31B_TABLE_SIZE, &sign, &b_yn, &xn, &th_cdc_fxp);
 
    th_cdc_fxp = sign * xn;
    /*convert Q2.30 to Q1.31 format*/
    return sat_int32(Q_SHIFT_LEFT((int64_t)th_cdc_fxp, 30, 31));
}
 
static inline int16_t sin_fixed_16b(int32_t th_rad_fxp)
{
    int32_t th_cdc_fxp;
    int32_t sign;
    int32_t b_yn;
    int32_t xn;
 
    cordic_approx(th_rad_fxp, CORDIC_15B_TABLE_SIZE, &sign, &b_yn, &xn, &th_cdc_fxp);
 
    th_cdc_fxp = sign * b_yn;
    /*convert Q2.30 to Q1.15 format*/
    return sat_int16(Q_SHIFT_RND(th_cdc_fxp, 30, 15));
}
 
static inline int16_t cos_fixed_16b(int32_t th_rad_fxp)
{
    int32_t th_cdc_fxp;
    int32_t sign;
    int32_t b_yn;
    int32_t xn;
 
    cordic_approx(th_rad_fxp, CORDIC_15B_TABLE_SIZE, &sign, &b_yn, &xn, &th_cdc_fxp);
 
    th_cdc_fxp = sign * xn;
    /*convert Q2.30 to Q1.15 format*/
    return sat_int16(Q_SHIFT_RND(th_cdc_fxp, 30, 15));
}
 
static inline void cmpx_exp_32b(int32_t th_rad_fxp, struct cordic_cmpx *cexp)
{
    int32_t th_cdc_fxp;
    int32_t sign;
    int32_t b_yn;
    int32_t xn;
 
    cordic_approx(th_rad_fxp, CORDIC_31B_TABLE_SIZE, &sign, &b_yn, &xn, &th_cdc_fxp);
    cmpx_cexp(sign, b_yn, xn, EN_32B_CORDIC_CEXP, cexp);
    /* return the complex(re & im) result in Q2.30*/
}
 
static inline void cmpx_exp_16b(int32_t th_rad_fxp, struct cordic_cmpx *cexp)
{
    int32_t th_cdc_fxp;
    int32_t sign;
    int32_t b_yn;
    int32_t xn;
 
    /* compute coeff from angles */
    cordic_approx(th_rad_fxp, CORDIC_15B_TABLE_SIZE, &sign, &b_yn, &xn, &th_cdc_fxp);
    cmpx_cexp(sign, b_yn, xn, EN_16B_CORDIC_CEXP, cexp);
    /* return the complex(re & im) result in Q1.15*/
}
 
static inline int32_t asin_fixed_32b(int32_t cdc_asin_th)
{
    int32_t th_asin_fxp;
 
    if (cdc_asin_th >= 0)
        th_asin_fxp = is_scalar_cordic_asin(cdc_asin_th, CORDIC_31B_ITERATIONS);
    else
        th_asin_fxp = -is_scalar_cordic_asin(-cdc_asin_th, CORDIC_31B_ITERATIONS);
 
    return th_asin_fxp; /* Q2.30 */
}
 
static inline int32_t acos_fixed_32b(int32_t cdc_acos_th)
{
    int32_t th_acos_fxp;
 
    if (cdc_acos_th >= 0)
        th_acos_fxp = is_scalar_cordic_acos(cdc_acos_th, CORDIC_31B_ITERATIONS);
    else
        th_acos_fxp = PI_Q3_29 - is_scalar_cordic_acos(-cdc_acos_th, CORDIC_31B_ITERATIONS);
 
    return th_acos_fxp; /* Q3.29 */
}
 
static inline int16_t asin_fixed_16b(int32_t cdc_asin_th)
{
    int32_t th_asin_fxp;
 
    if (cdc_asin_th >= 0)
        th_asin_fxp = is_scalar_cordic_asin(cdc_asin_th, CORDIC_16B_ITERATIONS);
    else
        th_asin_fxp = -is_scalar_cordic_asin(-cdc_asin_th, CORDIC_16B_ITERATIONS);
    /*convert Q2.30 to Q2.14 format*/
    return sat_int16(Q_SHIFT_RND(th_asin_fxp, 30, 14));
}
 
static inline int16_t acos_fixed_16b(int32_t cdc_acos_th)
{
    int32_t th_acos_fxp;
 
    if (cdc_acos_th >= 0)
        th_acos_fxp = is_scalar_cordic_acos(cdc_acos_th, CORDIC_16B_ITERATIONS);
    else
        th_acos_fxp = PI_Q3_29 - is_scalar_cordic_acos(-cdc_acos_th, CORDIC_16B_ITERATIONS);
 
    /*convert Q3.29 to Q3.13 format*/
    return sat_int16(Q_SHIFT_RND(th_acos_fxp, 29, 13));
}
 
int32_t sofm_atan2_32b(int32_t y, int32_t x);
 
#endif /* __SOF_MATH_TRIG_H__ */