From 86608c6770cf08c138a2bdab5855072f64be09ef Mon Sep 17 00:00:00 2001 From: joshua Date: Sat, 30 Dec 2023 23:54:31 -0500 Subject: initial commit --- .../DSP/Source/TransformFunctions/arm_rfft_q15.c | 380 +++++++++++++++++++++ 1 file changed, 380 insertions(+) create mode 100644 Drivers/CMSIS/DSP/Source/TransformFunctions/arm_rfft_q15.c (limited to 'Drivers/CMSIS/DSP/Source/TransformFunctions/arm_rfft_q15.c') diff --git a/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_rfft_q15.c b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_rfft_q15.c new file mode 100644 index 0000000..29d12b7 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_rfft_q15.c @@ -0,0 +1,380 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_rfft_q15.c + * Description: RFFT & RIFFT Q15 process function + * + * $Date: 18. March 2019 + * $Revision: V1.6.0 + * + * Target Processor: Cortex-M cores + * -------------------------------------------------------------------- */ +/* + * Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved. + * + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed under the Apache License, Version 2.0 (the License); you may + * not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an AS IS BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "arm_math.h" + +/* ---------------------------------------------------------------------- + * Internal functions prototypes + * -------------------------------------------------------------------- */ + +void arm_split_rfft_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pATable, + const q15_t * pBTable, + q15_t * pDst, + uint32_t modifier); + +void arm_split_rifft_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pATable, + const q15_t * pBTable, + q15_t * pDst, + uint32_t modifier); + +/** + @addtogroup RealFFT + @{ + */ + +/** + @brief Processing function for the Q15 RFFT/RIFFT. + @param[in] S points to an instance of the Q15 RFFT/RIFFT structure + @param[in] pSrc points to input buffer + @param[out] pDst points to output buffer + @return none + + @par Input an output formats + Internally input is downscaled by 2 for every stage to avoid saturations inside CFFT/CIFFT process. + Hence the output format is different for different RFFT sizes. + The input and output formats for different RFFT sizes and number of bits to upscale are mentioned in the tables below for RFFT and RIFFT: + @par + \image html RFFTQ15.gif "Input and Output Formats for Q15 RFFT" + @par + \image html RIFFTQ15.gif "Input and Output Formats for Q15 RIFFT" + */ + +void arm_rfft_q15( + const arm_rfft_instance_q15 * S, + q15_t * pSrc, + q15_t * pDst) +{ + const arm_cfft_instance_q15 *S_CFFT = S->pCfft; + uint32_t L2 = S->fftLenReal >> 1U; + uint32_t i; + + /* Calculation of RIFFT of input */ + if (S->ifftFlagR == 1U) + { + /* Real IFFT core process */ + arm_split_rifft_q15 (pSrc, L2, S->pTwiddleAReal, S->pTwiddleBReal, pDst, S->twidCoefRModifier); + + /* Complex IFFT process */ + arm_cfft_q15 (S_CFFT, pDst, S->ifftFlagR, S->bitReverseFlagR); + + for(i = 0; i < S->fftLenReal; i++) + { + pDst[i] = pDst[i] << 1U; + } + } + else + { + /* Calculation of RFFT of input */ + + /* Complex FFT process */ + arm_cfft_q15 (S_CFFT, pSrc, S->ifftFlagR, S->bitReverseFlagR); + + /* Real FFT core process */ + arm_split_rfft_q15 (pSrc, L2, S->pTwiddleAReal, S->pTwiddleBReal, pDst, S->twidCoefRModifier); + } + +} + +/** + @} end of RealFFT group + */ + +/** + @brief Core Real FFT process + @param[in] pSrc points to input buffer + @param[in] fftLen length of FFT + @param[in] pATable points to twiddle Coef A buffer + @param[in] pBTable points to twiddle Coef B buffer + @param[out] pDst points to output buffer + @param[in] modifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table + @return none + + @par + The function implements a Real FFT + */ + +void arm_split_rfft_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pATable, + const q15_t * pBTable, + q15_t * pDst, + uint32_t modifier) +{ + uint32_t i; /* Loop Counter */ + q31_t outR, outI; /* Temporary variables for output */ + const q15_t *pCoefA, *pCoefB; /* Temporary pointers for twiddle factors */ + q15_t *pSrc1, *pSrc2; +#if defined (ARM_MATH_DSP) + q15_t *pD1, *pD2; +#endif + + /* Init coefficient pointers */ + pCoefA = &pATable[modifier * 2]; + pCoefB = &pBTable[modifier * 2]; + + pSrc1 = &pSrc[2]; + pSrc2 = &pSrc[(2U * fftLen) - 2U]; + +#if defined (ARM_MATH_DSP) + + i = 1U; + pD1 = pDst + 2; + pD2 = pDst + (4U * fftLen) - 2; + + for (i = fftLen - 1; i > 0; i--) + { + /* + outR = ( pSrc[2 * i] * pATable[2 * i] + - pSrc[2 * i + 1] * pATable[2 * i + 1] + + pSrc[2 * n - 2 * i] * pBTable[2 * i] + + pSrc[2 * n - 2 * i + 1] * pBTable[2 * i + 1]); + + outI = ( pIn[2 * i + 1] * pATable[2 * i] + + pIn[2 * i] * pATable[2 * i + 1] + + pIn[2 * n - 2 * i] * pBTable[2 * i + 1] + - pIn[2 * n - 2 * i + 1] * pBTable[2 * i]) + */ + + +#ifndef ARM_MATH_BIG_ENDIAN + /* pSrc[2 * i] * pATable[2 * i] - pSrc[2 * i + 1] * pATable[2 * i + 1] */ + outR = __SMUSD(read_q15x2 (pSrc1), read_q15x2((q15_t *) pCoefA)); +#else + /* -(pSrc[2 * i + 1] * pATable[2 * i + 1] - pSrc[2 * i] * pATable[2 * i]) */ + outR = -(__SMUSD(read_q15x2 (pSrc1), read_q15x2((q15_t *) pCoefA))); +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + /* pSrc[2 * n - 2 * i] * pBTable[2 * i] + pSrc[2 * n - 2 * i + 1] * pBTable[2 * i + 1]) */ + outR = __SMLAD(read_q15x2 (pSrc2), read_q15x2((q15_t *) pCoefB), outR) >> 16U; + + /* pIn[2 * n - 2 * i] * pBTable[2 * i + 1] - pIn[2 * n - 2 * i + 1] * pBTable[2 * i] */ +#ifndef ARM_MATH_BIG_ENDIAN + outI = __SMUSDX(read_q15x2_da (&pSrc2), read_q15x2((q15_t *) pCoefB)); +#else + outI = __SMUSDX(read_q15x2 ((q15_t *) pCoefB), read_q15x2_da (&pSrc2)); +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + /* (pIn[2 * i + 1] * pATable[2 * i] + pIn[2 * i] * pATable[2 * i + 1] */ + outI = __SMLADX(read_q15x2_ia (&pSrc1), read_q15x2 ((q15_t *) pCoefA), outI); + + /* write output */ + *pD1++ = (q15_t) outR; + *pD1++ = outI >> 16U; + + /* write complex conjugate output */ + pD2[0] = (q15_t) outR; + pD2[1] = -(outI >> 16U); + pD2 -= 2; + + /* update coefficient pointer */ + pCoefB = pCoefB + (2U * modifier); + pCoefA = pCoefA + (2U * modifier); + } + + pDst[2U * fftLen] = (pSrc[0] - pSrc[1]) >> 1U; + pDst[2U * fftLen + 1U] = 0; + + pDst[0] = (pSrc[0] + pSrc[1]) >> 1U; + pDst[1] = 0; + +#else + + i = 1U; + + while (i < fftLen) + { + /* + outR = ( pSrc[2 * i] * pATable[2 * i] + - pSrc[2 * i + 1] * pATable[2 * i + 1] + + pSrc[2 * n - 2 * i] * pBTable[2 * i] + + pSrc[2 * n - 2 * i + 1] * pBTable[2 * i + 1]); + */ + + outR = *pSrc1 * *pCoefA; + outR = outR - (*(pSrc1 + 1) * *(pCoefA + 1)); + outR = outR + (*pSrc2 * *pCoefB); + outR = (outR + (*(pSrc2 + 1) * *(pCoefB + 1))) >> 16; + + /* + outI = ( pIn[2 * i + 1] * pATable[2 * i] + + pIn[2 * i] * pATable[2 * i + 1] + + pIn[2 * n - 2 * i] * pBTable[2 * i + 1] + - pIn[2 * n - 2 * i + 1] * pBTable[2 * i]); + */ + + outI = *pSrc2 * *(pCoefB + 1); + outI = outI - (*(pSrc2 + 1) * *pCoefB); + outI = outI + (*(pSrc1 + 1) * *pCoefA); + outI = outI + (*pSrc1 * *(pCoefA + 1)); + + /* update input pointers */ + pSrc1 += 2U; + pSrc2 -= 2U; + + /* write output */ + pDst[2U * i] = (q15_t) outR; + pDst[2U * i + 1U] = outI >> 16U; + + /* write complex conjugate output */ + pDst[(4U * fftLen) - (2U * i)] = (q15_t) outR; + pDst[((4U * fftLen) - (2U * i)) + 1U] = -(outI >> 16U); + + /* update coefficient pointer */ + pCoefB = pCoefB + (2U * modifier); + pCoefA = pCoefA + (2U * modifier); + + i++; + } + + pDst[2U * fftLen] = (pSrc[0] - pSrc[1]) >> 1; + pDst[2U * fftLen + 1U] = 0; + + pDst[0] = (pSrc[0] + pSrc[1]) >> 1; + pDst[1] = 0; + +#endif /* #if defined (ARM_MATH_DSP) */ +} + + +/** + @brief Core Real IFFT process + @param[in] pSrc points to input buffer + @param[in] fftLen length of FFT + @param[in] pATable points to twiddle Coef A buffer + @param[in] pBTable points to twiddle Coef B buffer + @param[out] pDst points to output buffer + @param[in] modifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table + @return none + + @par + The function implements a Real IFFT + */ + +void arm_split_rifft_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pATable, + const q15_t * pBTable, + q15_t * pDst, + uint32_t modifier) +{ + uint32_t i; /* Loop Counter */ + q31_t outR, outI; /* Temporary variables for output */ + const q15_t *pCoefA, *pCoefB; /* Temporary pointers for twiddle factors */ + q15_t *pSrc1, *pSrc2; + q15_t *pDst1 = &pDst[0]; + + pCoefA = &pATable[0]; + pCoefB = &pBTable[0]; + + pSrc1 = &pSrc[0]; + pSrc2 = &pSrc[2 * fftLen]; + + i = fftLen; + while (i > 0U) + { + /* + outR = ( pIn[2 * i] * pATable[2 * i] + + pIn[2 * i + 1] * pATable[2 * i + 1] + + pIn[2 * n - 2 * i] * pBTable[2 * i] + - pIn[2 * n - 2 * i + 1] * pBTable[2 * i + 1]); + + outI = ( pIn[2 * i + 1] * pATable[2 * i] + - pIn[2 * i] * pATable[2 * i + 1] + - pIn[2 * n - 2 * i] * pBTable[2 * i + 1] + - pIn[2 * n - 2 * i + 1] * pBTable[2 * i]); + */ + +#if defined (ARM_MATH_DSP) + +#ifndef ARM_MATH_BIG_ENDIAN + /* pIn[2 * n - 2 * i] * pBTable[2 * i] - pIn[2 * n - 2 * i + 1] * pBTable[2 * i + 1]) */ + outR = __SMUSD(read_q15x2(pSrc2), read_q15x2((q15_t *) pCoefB)); +#else + /* -(-pIn[2 * n - 2 * i] * pBTable[2 * i] + pIn[2 * n - 2 * i + 1] * pBTable[2 * i + 1])) */ + outR = -(__SMUSD(read_q15x2(pSrc2), read_q15x2((q15_t *) pCoefB))); +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + /* pIn[2 * i] * pATable[2 * i] + pIn[2 * i + 1] * pATable[2 * i + 1] + pIn[2 * n - 2 * i] * pBTable[2 * i] */ + outR = __SMLAD(read_q15x2(pSrc1), read_q15x2 ((q15_t *) pCoefA), outR) >> 16U; + + /* -pIn[2 * n - 2 * i] * pBTable[2 * i + 1] + pIn[2 * n - 2 * i + 1] * pBTable[2 * i] */ + outI = __SMUADX(read_q15x2_da (&pSrc2), read_q15x2((q15_t *) pCoefB)); + + /* pIn[2 * i + 1] * pATable[2 * i] - pIn[2 * i] * pATable[2 * i + 1] */ +#ifndef ARM_MATH_BIG_ENDIAN + outI = __SMLSDX(read_q15x2 ((q15_t *) pCoefA), read_q15x2_ia (&pSrc1), -outI); +#else + outI = __SMLSDX(read_q15x2_ia (&pSrc1), read_q15x2 ((q15_t *) pCoefA), -outI); +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + /* write output */ +#ifndef ARM_MATH_BIG_ENDIAN + write_q15x2_ia (&pDst1, __PKHBT(outR, (outI >> 16U), 16)); +#else + write_q15x2_ia (&pDst1, __PKHBT((outI >> 16U), outR, 16)); +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + +#else /* #if defined (ARM_MATH_DSP) */ + + outR = *pSrc2 * *pCoefB; + outR = outR - (*(pSrc2 + 1) * *(pCoefB + 1)); + outR = outR + (*pSrc1 * *pCoefA); + outR = (outR + (*(pSrc1 + 1) * *(pCoefA + 1))) >> 16; + + outI = *(pSrc1 + 1) * *pCoefA; + outI = outI - (*pSrc1 * *(pCoefA + 1)); + outI = outI - (*pSrc2 * *(pCoefB + 1)); + outI = outI - (*(pSrc2 + 1) * *(pCoefB)); + + /* update input pointers */ + pSrc1 += 2U; + pSrc2 -= 2U; + + /* write output */ + *pDst1++ = (q15_t) outR; + *pDst1++ = (q15_t) (outI >> 16); + +#endif /* #if defined (ARM_MATH_DSP) */ + + /* update coefficient pointer */ + pCoefB = pCoefB + (2 * modifier); + pCoefA = pCoefA + (2 * modifier); + + i--; + } + +} -- cgit v1.2.3