+++ /dev/null
-/* ----------------------------------------------------------------------
-* Copyright (C) 2010-2013 ARM Limited. All rights reserved.
-*
-* $Date: 17. January 2013
-* $Revision: V1.4.1
-*
-* Project: CMSIS DSP Library
-* Title: arm_cfft_radix2_q31.c
-*
-* Description: Radix-2 Decimation in Frequency CFFT & CIFFT Fixed point processing function
-*
-*
-* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
-*
-* Redistribution and use in source and binary forms, with or without
-* modification, are permitted provided that the following conditions
-* are met:
-* - Redistributions of source code must retain the above copyright
-* notice, this list of conditions and the following disclaimer.
-* - Redistributions in binary form must reproduce the above copyright
-* notice, this list of conditions and the following disclaimer in
-* the documentation and/or other materials provided with the
-* distribution.
-* - Neither the name of ARM LIMITED nor the names of its contributors
-* may be used to endorse or promote products derived from this
-* software without specific prior written permission.
-*
-* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
-* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
-* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
-* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
-* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
-* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-* POSSIBILITY OF SUCH DAMAGE.
-* -------------------------------------------------------------------- */
-
-#include "arm_math.h"
-
-void arm_radix2_butterfly_q31(
- q31_t * pSrc,
- uint32_t fftLen,
- q31_t * pCoef,
- uint16_t twidCoefModifier);
-
-void arm_radix2_butterfly_inverse_q31(
- q31_t * pSrc,
- uint32_t fftLen,
- q31_t * pCoef,
- uint16_t twidCoefModifier);
-
-void arm_bitreversal_q31(
- q31_t * pSrc,
- uint32_t fftLen,
- uint16_t bitRevFactor,
- uint16_t * pBitRevTab);
-
-/**
-* @ingroup groupTransforms
-*/
-
-/**
-* @addtogroup ComplexFFT
-* @{
-*/
-
-/**
-* @details
-* @brief Processing function for the fixed-point CFFT/CIFFT.
-* @param[in] *S points to an instance of the fixed-point CFFT/CIFFT structure.
-* @param[in, out] *pSrc points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place.
-* @return none.
-*/
-
-void arm_cfft_radix2_q31(
-const arm_cfft_radix2_instance_q31 * S,
-q31_t * pSrc)
-{
-
- if(S->ifftFlag == 1u)
- {
- arm_radix2_butterfly_inverse_q31(pSrc, S->fftLen,
- S->pTwiddle, S->twidCoefModifier);
- }
- else
- {
- arm_radix2_butterfly_q31(pSrc, S->fftLen,
- S->pTwiddle, S->twidCoefModifier);
- }
-
- arm_bitreversal_q31(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable);
-}
-
-/**
-* @} end of ComplexFFT group
-*/
-
-void arm_radix2_butterfly_q31(
-q31_t * pSrc,
-uint32_t fftLen,
-q31_t * pCoef,
-uint16_t twidCoefModifier)
-{
-
- unsigned i, j, k, l, m;
- unsigned n1, n2, ia;
- q31_t xt, yt, cosVal, sinVal;
- q31_t p0, p1;
-
- //N = fftLen;
- n2 = fftLen;
-
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
-
- // loop for groups
- for (i = 0; i < n2; i++)
- {
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
-
- l = i + n2;
- xt = (pSrc[2 * i] >> 2u) - (pSrc[2 * l] >> 2u);
- pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
-
- yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
- pSrc[2 * i + 1] =
- ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 1u;
-
- mult_32x32_keep32_R(p0, xt, cosVal);
- mult_32x32_keep32_R(p1, yt, cosVal);
- multAcc_32x32_keep32_R(p0, yt, sinVal);
- multSub_32x32_keep32_R(p1, xt, sinVal);
-
- pSrc[2u * l] = p0;
- pSrc[2u * l + 1u] = p1;
-
- } // groups loop end
-
- twidCoefModifier <<= 1u;
-
- // loop for stage
- for (k = fftLen / 2; k > 2; k = k >> 1)
- {
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
-
- // loop for groups
- for (j = 0; j < n2; j++)
- {
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
-
- // loop for butterfly
- i = j;
- m = fftLen / n1;
- do
- {
- l = i + n2;
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
-
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
-
- mult_32x32_keep32_R(p0, xt, cosVal);
- mult_32x32_keep32_R(p1, yt, cosVal);
- multAcc_32x32_keep32_R(p0, yt, sinVal);
- multSub_32x32_keep32_R(p1, xt, sinVal);
-
- pSrc[2u * l] = p0;
- pSrc[2u * l + 1u] = p1;
- i += n1;
- m--;
- } while( m > 0); // butterfly loop end
-
- } // groups loop end
-
- twidCoefModifier <<= 1u;
- } // stages loop end
-
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
-
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
-
- // loop for butterfly
- for (i = 0; i < fftLen; i += n1)
- {
- l = i + n2;
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
-
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
-
- pSrc[2u * l] = xt;
-
- pSrc[2u * l + 1u] = yt;
-
- i += n1;
- l = i + n2;
-
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
-
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
-
- pSrc[2u * l] = xt;
-
- pSrc[2u * l + 1u] = yt;
-
- } // butterfly loop end
-
-}
-
-
-void arm_radix2_butterfly_inverse_q31(
-q31_t * pSrc,
-uint32_t fftLen,
-q31_t * pCoef,
-uint16_t twidCoefModifier)
-{
-
- unsigned i, j, k, l;
- unsigned n1, n2, ia;
- q31_t xt, yt, cosVal, sinVal;
- q31_t p0, p1;
-
- //N = fftLen;
- n2 = fftLen;
-
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
-
- // loop for groups
- for (i = 0; i < n2; i++)
- {
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
-
- l = i + n2;
- xt = (pSrc[2 * i] >> 2u) - (pSrc[2 * l] >> 2u);
- pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
-
- yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
- pSrc[2 * i + 1] =
- ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 1u;
-
- mult_32x32_keep32_R(p0, xt, cosVal);
- mult_32x32_keep32_R(p1, yt, cosVal);
- multSub_32x32_keep32_R(p0, yt, sinVal);
- multAcc_32x32_keep32_R(p1, xt, sinVal);
-
- pSrc[2u * l] = p0;
- pSrc[2u * l + 1u] = p1;
- } // groups loop end
-
- twidCoefModifier = twidCoefModifier << 1u;
-
- // loop for stage
- for (k = fftLen / 2; k > 2; k = k >> 1)
- {
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
-
- // loop for groups
- for (j = 0; j < n2; j++)
- {
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
-
- // loop for butterfly
- for (i = j; i < fftLen; i += n1)
- {
- l = i + n2;
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
-
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
-
- mult_32x32_keep32_R(p0, xt, cosVal);
- mult_32x32_keep32_R(p1, yt, cosVal);
- multSub_32x32_keep32_R(p0, yt, sinVal);
- multAcc_32x32_keep32_R(p1, xt, sinVal);
-
- pSrc[2u * l] = p0;
- pSrc[2u * l + 1u] = p1;
- } // butterfly loop end
-
- } // groups loop end
-
- twidCoefModifier = twidCoefModifier << 1u;
- } // stages loop end
-
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
-
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
-
- // loop for butterfly
- for (i = 0; i < fftLen; i += n1)
- {
- l = i + n2;
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
-
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
-
- pSrc[2u * l] = xt;
-
- pSrc[2u * l + 1u] = yt;
-
- i += n1;
- l = i + n2;
-
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
-
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
-
- pSrc[2u * l] = xt;
-
- pSrc[2u * l + 1u] = yt;
-
- } // butterfly loop end
-
-}
projects / qmk_firmware.git / blobdiff