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 --- .../FilteringFunctions/arm_fir_decimate_f32.c | 512 +++++++++++++++++++++ 1 file changed, 512 insertions(+) create mode 100644 fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_decimate_f32.c (limited to 'fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_decimate_f32.c') diff --git a/fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_decimate_f32.c b/fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_decimate_f32.c new file mode 100644 index 0000000..fd8e237 --- /dev/null +++ b/fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_decimate_f32.c @@ -0,0 +1,512 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_fir_decimate_f32.c + * Description: FIR decimation for floating-point sequences + * + * $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 + */ + +/** + * @defgroup FIR_decimate Finite Impulse Response (FIR) Decimator + * + * These functions combine an FIR filter together with a decimator. + * They are used in multirate systems for reducing the sample rate of a signal without introducing aliasing distortion. + * Conceptually, the functions are equivalent to the block diagram below: + * \image html FIRDecimator.gif "Components included in the FIR Decimator functions" + * When decimating by a factor of M, the signal should be prefiltered by a lowpass filter with a normalized + * cutoff frequency of 1/M in order to prevent aliasing distortion. + * The user of the function is responsible for providing the filter coefficients. + * + * The FIR decimator functions provided in the CMSIS DSP Library combine the FIR filter and the decimator in an efficient manner. + * Instead of calculating all of the FIR filter outputs and discarding M-1 out of every M, only the + * samples output by the decimator are computed. + * The functions operate on blocks of input and output data. + * pSrc points to an array of blockSize input values and + * pDst points to an array of blockSize/M output values. + * In order to have an integer number of output samples blockSize + * must always be a multiple of the decimation factor M. + * + * The library provides separate functions for Q15, Q31 and floating-point data types. + * + * \par Algorithm: + * The FIR portion of the algorithm uses the standard form filter: + * 
+ *    y[n] = b[0] * x[n] + b[1] * x[n-1] + b[2] * x[n-2] + ...+ b[numTaps-1] * x[n-numTaps+1]
+ *
+ * where, b[n] are the filter coefficients. + * \par + * The pCoeffs points to a coefficient array of size numTaps. + * Coefficients are stored in time reversed order. + * \par + * 
+ *    {b[numTaps-1], b[numTaps-2], b[N-2], ..., b[1], b[0]}
+ *
+ * \par + * pState points to a state array of size numTaps + blockSize - 1. + * Samples in the state buffer are stored in the order: + * \par + * 
+ *    {x[n-numTaps+1], x[n-numTaps], x[n-numTaps-1], x[n-numTaps-2]....x[0], x[1], ..., x[blockSize-1]}
+ *
+ * The state variables are updated after each block of data is processed, the coefficients are untouched. + * + * \par Instance Structure + * The coefficients and state variables for a filter are stored together in an instance data structure. + * A separate instance structure must be defined for each filter. + * Coefficient arrays may be shared among several instances while state variable array should be allocated separately. + * There are separate instance structure declarations for each of the 3 supported data types. + * + * \par Initialization Functions + * There is also an associated initialization function for each data type. + * The initialization function performs the following operations: + * - Sets the values of the internal structure fields. + * - Zeros out the values in the state buffer. + * - Checks to make sure that the size of the input is a multiple of the decimation factor. + * To do this manually without calling the init function, assign the follow subfields of the instance structure: + * numTaps, pCoeffs, M (decimation factor), pState. Also set all of the values in pState to zero. + * + * \par + * Use of the initialization function is optional. + * However, if the initialization function is used, then the instance structure cannot be placed into a const data section. + * To place an instance structure into a const data section, the instance structure must be manually initialized. + * The code below statically initializes each of the 3 different data type filter instance structures + * 
+ *arm_fir_decimate_instance_f32 S = {M, numTaps, pCoeffs, pState};
+ *arm_fir_decimate_instance_q31 S = {M, numTaps, pCoeffs, pState};
+ *arm_fir_decimate_instance_q15 S = {M, numTaps, pCoeffs, pState};
+ *
+ * where M is the decimation factor; numTaps is the number of filter coefficients in the filter; + * pCoeffs is the address of the coefficient buffer; + * pState is the address of the state buffer. + * Be sure to set the values in the state buffer to zeros when doing static initialization. + * + * \par Fixed-Point Behavior + * Care must be taken when using the fixed-point versions of the FIR decimate filter functions. + * In particular, the overflow and saturation behavior of the accumulator used in each function must be considered. + * Refer to the function specific documentation below for usage guidelines. + */ + +/** + * @addtogroup FIR_decimate + * @{ + */ + + /** + * @brief Processing function for the floating-point FIR decimator. + * @param[in] *S points to an instance of the floating-point FIR decimator 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 input samples to process per call. + * @return none. + */ + +void arm_fir_decimate_f32( + const arm_fir_decimate_instance_f32 * S, + float32_t * pSrc, + float32_t * pDst, + uint32_t blockSize) +{ + float32_t *pState = S->pState; /* State pointer */ + float32_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */ + float32_t *pStateCurnt; /* Points to the current sample of the state */ + float32_t *px, *pb; /* Temporary pointers for state and coefficient buffers */ + float32_t sum0; /* Accumulator */ + float32_t x0, c0; /* Temporary variables to hold state and coefficient values */ + uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */ + uint32_t i, tapCnt, blkCnt, outBlockSize = blockSize / S->M; /* Loop counters */ + +#if defined (ARM_MATH_DSP) + + uint32_t blkCntN4; + float32_t *px0, *px1, *px2, *px3; + float32_t acc0, acc1, acc2, acc3; + float32_t x1, x2, x3; + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + + /* S->pState buffer contains previous frame (numTaps - 1) samples */ + /* pStateCurnt points to the location where the new input data should be written */ + pStateCurnt = S->pState + (numTaps - 1U); + + /* Total number of output samples to be computed */ + blkCnt = outBlockSize / 4; + blkCntN4 = outBlockSize - (4 * blkCnt); + + while (blkCnt > 0U) + { + /* Copy 4 * decimation factor number of new input samples into the state buffer */ + i = 4 * S->M; + + do + { + *pStateCurnt++ = *pSrc++; + + } while (--i); + + /* Set accumulators to zero */ + acc0 = 0.0f; + acc1 = 0.0f; + acc2 = 0.0f; + acc3 = 0.0f; + + /* Initialize state pointer for all the samples */ + px0 = pState; + px1 = pState + S->M; + px2 = pState + 2 * S->M; + px3 = pState + 3 * S->M; + + /* Initialize coeff pointer */ + pb = pCoeffs; + + /* Loop unrolling. Process 4 taps at a time. */ + tapCnt = numTaps >> 2; + + /* Loop over the number of taps. Unroll by a factor of 4. + ** Repeat until we've computed numTaps-4 coefficients. */ + + while (tapCnt > 0U) + { + /* Read the b[numTaps-1] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-1] sample for acc0 */ + x0 = *(px0++); + /* Read x[n-numTaps-1] sample for acc1 */ + x1 = *(px1++); + /* Read x[n-numTaps-1] sample for acc2 */ + x2 = *(px2++); + /* Read x[n-numTaps-1] sample for acc3 */ + x3 = *(px3++); + + /* Perform the multiply-accumulate */ + acc0 += x0 * c0; + acc1 += x1 * c0; + acc2 += x2 * c0; + acc3 += x3 * c0; + + /* Read the b[numTaps-2] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-2] sample for acc0, acc1, acc2, acc3 */ + x0 = *(px0++); + x1 = *(px1++); + x2 = *(px2++); + x3 = *(px3++); + + /* Perform the multiply-accumulate */ + acc0 += x0 * c0; + acc1 += x1 * c0; + acc2 += x2 * c0; + acc3 += x3 * c0; + + /* Read the b[numTaps-3] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-3] sample acc0, acc1, acc2, acc3 */ + x0 = *(px0++); + x1 = *(px1++); + x2 = *(px2++); + x3 = *(px3++); + + /* Perform the multiply-accumulate */ + acc0 += x0 * c0; + acc1 += x1 * c0; + acc2 += x2 * c0; + acc3 += x3 * c0; + + /* Read the b[numTaps-4] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-4] sample acc0, acc1, acc2, acc3 */ + x0 = *(px0++); + x1 = *(px1++); + x2 = *(px2++); + x3 = *(px3++); + + /* Perform the multiply-accumulate */ + acc0 += x0 * c0; + acc1 += x1 * c0; + acc2 += x2 * c0; + acc3 += x3 * c0; + + /* Decrement the loop counter */ + tapCnt--; + } + + /* If the filter length is not a multiple of 4, compute the remaining filter taps */ + tapCnt = numTaps % 0x4U; + + while (tapCnt > 0U) + { + /* Read coefficients */ + c0 = *(pb++); + + /* Fetch state variables for acc0, acc1, acc2, acc3 */ + x0 = *(px0++); + x1 = *(px1++); + x2 = *(px2++); + x3 = *(px3++); + + /* Perform the multiply-accumulate */ + acc0 += x0 * c0; + acc1 += x1 * c0; + acc2 += x2 * c0; + acc3 += x3 * c0; + + /* Decrement the loop counter */ + tapCnt--; + } + + /* Advance the state pointer by the decimation factor + * to process the next group of decimation factor number samples */ + pState = pState + 4 * S->M; + + /* The result is in the accumulator, store in the destination buffer. */ + *pDst++ = acc0; + *pDst++ = acc1; + *pDst++ = acc2; + *pDst++ = acc3; + + /* Decrement the loop counter */ + blkCnt--; + } + + while (blkCntN4 > 0U) + { + /* Copy decimation factor number of new input samples into the state buffer */ + i = S->M; + + do + { + *pStateCurnt++ = *pSrc++; + + } while (--i); + + /* Set accumulator to zero */ + sum0 = 0.0f; + + /* Initialize state pointer */ + px = pState; + + /* Initialize coeff pointer */ + pb = pCoeffs; + + /* Loop unrolling. Process 4 taps at a time. */ + tapCnt = numTaps >> 2; + + /* Loop over the number of taps. Unroll by a factor of 4. + ** Repeat until we've computed numTaps-4 coefficients. */ + while (tapCnt > 0U) + { + /* Read the b[numTaps-1] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-1] sample */ + x0 = *(px++); + + /* Perform the multiply-accumulate */ + sum0 += x0 * c0; + + /* Read the b[numTaps-2] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-2] sample */ + x0 = *(px++); + + /* Perform the multiply-accumulate */ + sum0 += x0 * c0; + + /* Read the b[numTaps-3] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-3] sample */ + x0 = *(px++); + + /* Perform the multiply-accumulate */ + sum0 += x0 * c0; + + /* Read the b[numTaps-4] coefficient */ + c0 = *(pb++); + + /* Read x[n-numTaps-4] sample */ + x0 = *(px++); + + /* Perform the multiply-accumulate */ + sum0 += x0 * c0; + + /* Decrement the loop counter */ + tapCnt--; + } + + /* If the filter length is not a multiple of 4, compute the remaining filter taps */ + tapCnt = numTaps % 0x4U; + + while (tapCnt > 0U) + { + /* Read coefficients */ + c0 = *(pb++); + + /* Fetch 1 state variable */ + x0 = *(px++); + + /* Perform the multiply-accumulate */ + sum0 += x0 * c0; + + /* Decrement the loop counter */ + tapCnt--; + } + + /* Advance the state pointer by the decimation factor + * to process the next group of decimation factor number samples */ + pState = pState + S->M; + + /* The result is in the accumulator, store in the destination buffer. */ + *pDst++ = sum0; + + /* Decrement the loop counter */ + blkCntN4--; + } + + /* Processing is complete. + ** Now copy the last numTaps - 1 samples to the satrt of the state buffer. + ** This prepares the state buffer for the next function call. */ + + /* Points to the start of the state buffer */ + pStateCurnt = S->pState; + + i = (numTaps - 1U) >> 2; + + /* copy data */ + while (i > 0U) + { + *pStateCurnt++ = *pState++; + *pStateCurnt++ = *pState++; + *pStateCurnt++ = *pState++; + *pStateCurnt++ = *pState++; + + /* Decrement the loop counter */ + i--; + } + + i = (numTaps - 1U) % 0x04U; + + /* copy data */ + while (i > 0U) + { + *pStateCurnt++ = *pState++; + + /* Decrement the loop counter */ + i--; + } + +#else + +/* Run the below code for Cortex-M0 */ + + /* S->pState buffer contains previous frame (numTaps - 1) samples */ + /* pStateCurnt points to the location where the new input data should be written */ + pStateCurnt = S->pState + (numTaps - 1U); + + /* Total number of output samples to be computed */ + blkCnt = outBlockSize; + + while (blkCnt > 0U) + { + /* Copy decimation factor number of new input samples into the state buffer */ + i = S->M; + + do + { + *pStateCurnt++ = *pSrc++; + + } while (--i); + + /* Set accumulator to zero */ + sum0 = 0.0f; + + /* Initialize state pointer */ + px = pState; + + /* Initialize coeff pointer */ + pb = pCoeffs; + + tapCnt = numTaps; + + while (tapCnt > 0U) + { + /* Read coefficients */ + c0 = *pb++; + + /* Fetch 1 state variable */ + x0 = *px++; + + /* Perform the multiply-accumulate */ + sum0 += x0 * c0; + + /* Decrement the loop counter */ + tapCnt--; + } + + /* Advance the state pointer by the decimation factor + * to process the next group of decimation factor number samples */ + pState = pState + S->M; + + /* The result is in the accumulator, store in the destination buffer. */ + *pDst++ = sum0; + + /* Decrement the loop counter */ + blkCnt--; + } + + /* Processing is complete. + ** Now copy the last numTaps - 1 samples to the start of the state buffer. + ** This prepares the state buffer for the next function call. */ + + /* Points to the start of the state buffer */ + pStateCurnt = S->pState; + + /* Copy numTaps number of values */ + i = (numTaps - 1U); + + /* copy data */ + while (i > 0U) + { + *pStateCurnt++ = *pState++; + + /* Decrement the loop counter */ + i--; + } + +#endif /* #if defined (ARM_MATH_DSP) */ + +} + +/** + * @} end of FIR_decimate group + */ -- cgit