From 6ab94e0b318884bbcb95e2ea3835f951502e1d99 Mon Sep 17 00:00:00 2001 From: jaseg Date: Wed, 14 Oct 2020 12:47:28 +0200 Subject: Move firmware into subdirectory --- .../arm_biquad_cascade_df1_fast_q15.c | 273 +++++++++++++++++++++ 1 file changed, 273 insertions(+) create mode 100644 fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_biquad_cascade_df1_fast_q15.c (limited to 'fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_biquad_cascade_df1_fast_q15.c') diff --git a/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_biquad_cascade_df1_fast_q15.c b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_biquad_cascade_df1_fast_q15.c new file mode 100644 index 0000000..2a08968 --- /dev/null +++ b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_biquad_cascade_df1_fast_q15.c @@ -0,0 +1,273 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_biquad_cascade_df1_fast_q15.c + * Description: Fast processing function for the Q15 Biquad cascade filter + * + * $Date: 27. January 2017 + * $Revision: V.1.5.1 + * + * Target Processor: Cortex-M cores + * -------------------------------------------------------------------- */ +/* + * Copyright (C) 2010-2017 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" + +/** + * @ingroup groupFilters + */ + +/** + * @addtogroup BiquadCascadeDF1 + * @{ + */ + +/** + * @details + * @param[in] *S points to an instance of the Q15 Biquad cascade structure. + * @param[in] *pSrc points to the block of input data. + * @param[out] *pDst points to the block of output data. + * @param[in] blockSize number of samples to process per call. + * @return none. + * + * Scaling and Overflow Behavior: + * \par + * This fast version uses a 32-bit accumulator with 2.30 format. + * The accumulator maintains full precision of the intermediate multiplication results but provides only a single guard bit. + * Thus, if the accumulator result overflows it wraps around and distorts the result. + * In order to avoid overflows completely the input signal must be scaled down by two bits and lie in the range [-0.25 +0.25). + * The 2.30 accumulator is then shifted by postShift bits and the result truncated to 1.15 format by discarding the low 16 bits. + * + * \par + * Refer to the function arm_biquad_cascade_df1_q15() for a slower implementation of this function which uses 64-bit accumulation to avoid wrap around distortion. Both the slow and the fast versions use the same instance structure. + * Use the function arm_biquad_cascade_df1_init_q15() to initialize the filter structure. + * + */ + +void arm_biquad_cascade_df1_fast_q15( + const arm_biquad_casd_df1_inst_q15 * S, + q15_t * pSrc, + q15_t * pDst, + uint32_t blockSize) +{ + q15_t *pIn = pSrc; /* Source pointer */ + q15_t *pOut = pDst; /* Destination pointer */ + q31_t in; /* Temporary variable to hold input value */ + q31_t out; /* Temporary variable to hold output value */ + q31_t b0; /* Temporary variable to hold bo value */ + q31_t b1, a1; /* Filter coefficients */ + q31_t state_in, state_out; /* Filter state variables */ + q31_t acc; /* Accumulator */ + int32_t shift = (int32_t) (15 - S->postShift); /* Post shift */ + q15_t *pState = S->pState; /* State pointer */ + q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */ + uint32_t sample, stage = S->numStages; /* Stage loop counter */ + + + + do + { + + /* Read the b0 and 0 coefficients using SIMD */ + b0 = *__SIMD32(pCoeffs)++; + + /* Read the b1 and b2 coefficients using SIMD */ + b1 = *__SIMD32(pCoeffs)++; + + /* Read the a1 and a2 coefficients using SIMD */ + a1 = *__SIMD32(pCoeffs)++; + + /* Read the input state values from the state buffer: x[n-1], x[n-2] */ + state_in = *__SIMD32(pState)++; + + /* Read the output state values from the state buffer: y[n-1], y[n-2] */ + state_out = *__SIMD32(pState)--; + + /* Apply loop unrolling and compute 2 output values simultaneously. */ + /* The variable acc hold output values that are being computed: + * + * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] + * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] + */ + sample = blockSize >> 1U; + + /* First part of the processing with loop unrolling. Compute 2 outputs at a time. + ** a second loop below computes the remaining 1 sample. */ + while (sample > 0U) + { + + /* Read the input */ + in = *__SIMD32(pIn)++; + + /* out = b0 * x[n] + 0 * 0 */ + out = __SMUAD(b0, in); + /* acc = b1 * x[n-1] + acc += b2 * x[n-2] + out */ + acc = __SMLAD(b1, state_in, out); + /* acc += a1 * y[n-1] + acc += a2 * y[n-2] */ + acc = __SMLAD(a1, state_out, acc); + + /* The result is converted from 3.29 to 1.31 and then saturation is applied */ + out = __SSAT((acc >> shift), 16); + + /* Every time after the output is computed state should be updated. */ + /* The states should be updated as: */ + /* Xn2 = Xn1 */ + /* Xn1 = Xn */ + /* Yn2 = Yn1 */ + /* Yn1 = acc */ + /* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */ + /* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */ + +#ifndef ARM_MATH_BIG_ENDIAN + + state_in = __PKHBT(in, state_in, 16); + state_out = __PKHBT(out, state_out, 16); + +#else + + state_in = __PKHBT(state_in >> 16, (in >> 16), 16); + state_out = __PKHBT(state_out >> 16, (out), 16); + +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + /* out = b0 * x[n] + 0 * 0 */ + out = __SMUADX(b0, in); + /* acc0 = b1 * x[n-1] , acc0 += b2 * x[n-2] + out */ + acc = __SMLAD(b1, state_in, out); + /* acc += a1 * y[n-1] + acc += a2 * y[n-2] */ + acc = __SMLAD(a1, state_out, acc); + + /* The result is converted from 3.29 to 1.31 and then saturation is applied */ + out = __SSAT((acc >> shift), 16); + + + /* Store the output in the destination buffer. */ + +#ifndef ARM_MATH_BIG_ENDIAN + + *__SIMD32(pOut)++ = __PKHBT(state_out, out, 16); + +#else + + *__SIMD32(pOut)++ = __PKHBT(out, state_out >> 16, 16); + +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + /* Every time after the output is computed state should be updated. */ + /* The states should be updated as: */ + /* Xn2 = Xn1 */ + /* Xn1 = Xn */ + /* Yn2 = Yn1 */ + /* Yn1 = acc */ + /* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */ + /* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */ + +#ifndef ARM_MATH_BIG_ENDIAN + + state_in = __PKHBT(in >> 16, state_in, 16); + state_out = __PKHBT(out, state_out, 16); + +#else + + state_in = __PKHBT(state_in >> 16, in, 16); + state_out = __PKHBT(state_out >> 16, out, 16); + +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + + /* Decrement the loop counter */ + sample--; + + } + + /* If the blockSize is not a multiple of 2, compute any remaining output samples here. + ** No loop unrolling is used. */ + + if ((blockSize & 0x1U) != 0U) + { + /* Read the input */ + in = *pIn++; + + /* out = b0 * x[n] + 0 * 0 */ + +#ifndef ARM_MATH_BIG_ENDIAN + + out = __SMUAD(b0, in); + +#else + + out = __SMUADX(b0, in); + +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + /* acc = b1 * x[n-1], acc += b2 * x[n-2] + out */ + acc = __SMLAD(b1, state_in, out); + /* acc += a1 * y[n-1] + acc += a2 * y[n-2] */ + acc = __SMLAD(a1, state_out, acc); + + /* The result is converted from 3.29 to 1.31 and then saturation is applied */ + out = __SSAT((acc >> shift), 16); + + /* Store the output in the destination buffer. */ + *pOut++ = (q15_t) out; + + /* Every time after the output is computed state should be updated. */ + /* The states should be updated as: */ + /* Xn2 = Xn1 */ + /* Xn1 = Xn */ + /* Yn2 = Yn1 */ + /* Yn1 = acc */ + /* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */ + /* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */ + +#ifndef ARM_MATH_BIG_ENDIAN + + state_in = __PKHBT(in, state_in, 16); + state_out = __PKHBT(out, state_out, 16); + +#else + + state_in = __PKHBT(state_in >> 16, in, 16); + state_out = __PKHBT(state_out >> 16, out, 16); + +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + } + + /* The first stage goes from the input buffer to the output buffer. */ + /* Subsequent (numStages - 1) occur in-place in the output buffer */ + pIn = pDst; + + /* Reset the output pointer */ + pOut = pDst; + + /* Store the updated state variables back into the state array */ + *__SIMD32(pState)++ = state_in; + *__SIMD32(pState)++ = state_out; + + + /* Decrement the loop counter */ + stage--; + + } while (stage > 0U); +} + + +/** + * @} end of BiquadCascadeDF1 group + */ -- cgit