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Diffstat (limited to 'fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_f32.c')
| -rw-r--r-- | fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_f32.c | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_f32.c b/fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_f32.c new file mode 100644 index 0000000..1b6d0fb --- /dev/null +++ b/fw/cdc-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_f32.c @@ -0,0 +1,494 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_fir_lattice_f32.c
+ * Description: Processing function for the floating-point FIR Lattice 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
+ */
+
+/**
+ * @defgroup FIR_Lattice Finite Impulse Response (FIR) Lattice Filters
+ *
+ * This set of functions implements Finite Impulse Response (FIR) lattice filters
+ * for Q15, Q31 and floating-point data types. Lattice filters are used in a
+ * variety of adaptive filter applications. The filter structure is feedforward and
+ * the net impulse response is finite length.
+ * The functions operate on blocks
+ * of input and output data and each call to the function processes
+ * <code>blockSize</code> samples through the filter. <code>pSrc</code> and
+ * <code>pDst</code> point to input and output arrays containing <code>blockSize</code> values.
+ *
+ * \par Algorithm:
+ * \image html FIRLattice.gif "Finite Impulse Response Lattice filter"
+ * The following difference equation is implemented:
+ * <pre>
+ * f0[n] = g0[n] = x[n]
+ * fm[n] = fm-1[n] + km * gm-1[n-1] for m = 1, 2, ...M
+ * gm[n] = km * fm-1[n] + gm-1[n-1] for m = 1, 2, ...M
+ * y[n] = fM[n]
+ * </pre>
+ * \par
+ * <code>pCoeffs</code> points to tha array of reflection coefficients of size <code>numStages</code>.
+ * Reflection Coefficients are stored in the following order.
+ * \par
+ * <pre>
+ * {k1, k2, ..., kM}
+ * </pre>
+ * where M is number of stages
+ * \par
+ * <code>pState</code> points to a state array of size <code>numStages</code>.
+ * The state variables (g values) hold previous inputs and are stored in the following order.
+ * <pre>
+ * {g0[n], g1[n], g2[n] ...gM-1[n]}
+ * </pre>
+ * 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 arrays cannot be shared.
+ * 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.
+ * To do this manually without calling the init function, assign the follow subfields of the instance structure:
+ * numStages, pCoeffs, 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.
+ * Set the values in the state buffer to zeros and then manually initialize the instance structure as follows:
+ * <pre>
+ *arm_fir_lattice_instance_f32 S = {numStages, pState, pCoeffs};
+ *arm_fir_lattice_instance_q31 S = {numStages, pState, pCoeffs};
+ *arm_fir_lattice_instance_q15 S = {numStages, pState, pCoeffs};
+ * </pre>
+ * \par
+ * where <code>numStages</code> is the number of stages in the filter; <code>pState</code> is the address of the state buffer;
+ * <code>pCoeffs</code> is the address of the coefficient buffer.
+ * \par Fixed-Point Behavior
+ * Care must be taken when using the fixed-point versions of the FIR Lattice 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_Lattice
+ * @{
+ */
+
+
+ /**
+ * @brief Processing function for the floating-point FIR lattice filter.
+ * @param[in] *S points to an instance of the floating-point FIR lattice 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.
+ * @return none.
+ */
+
+void arm_fir_lattice_f32(
+ const arm_fir_lattice_instance_f32 * S,
+ float32_t * pSrc,
+ float32_t * pDst,
+ uint32_t blockSize)
+{
+ float32_t *pState; /* State pointer */
+ float32_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
+ float32_t *px; /* temporary state pointer */
+ float32_t *pk; /* temporary coefficient pointer */
+
+
+#if defined (ARM_MATH_DSP)
+
+ /* Run the below code for Cortex-M4 and Cortex-M3 */
+
+ float32_t fcurr1, fnext1, gcurr1, gnext1; /* temporary variables for first sample in loop unrolling */
+ float32_t fcurr2, fnext2, gnext2; /* temporary variables for second sample in loop unrolling */
+ float32_t fcurr3, fnext3, gnext3; /* temporary variables for third sample in loop unrolling */
+ float32_t fcurr4, fnext4, gnext4; /* temporary variables for fourth sample in loop unrolling */
+ uint32_t numStages = S->numStages; /* Number of stages in the filter */
+ uint32_t blkCnt, stageCnt; /* temporary variables for counts */
+
+ gcurr1 = 0.0f;
+ pState = &S->pState[0];
+
+ blkCnt = blockSize >> 2;
+
+ /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
+ a second loop below computes the remaining 1 to 3 samples. */
+ while (blkCnt > 0U)
+ {
+
+ /* Read two samples from input buffer */
+ /* f0(n) = x(n) */
+ fcurr1 = *pSrc++;
+ fcurr2 = *pSrc++;
+
+ /* Initialize coeff pointer */
+ pk = (pCoeffs);
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Read g0(n-1) from state */
+ gcurr1 = *px;
+
+ /* Process first sample for first tap */
+ /* f1(n) = f0(n) + K1 * g0(n-1) */
+ fnext1 = fcurr1 + ((*pk) * gcurr1);
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext1 = (fcurr1 * (*pk)) + gcurr1;
+
+ /* Process second sample for first tap */
+ /* for sample 2 processing */
+ fnext2 = fcurr2 + ((*pk) * fcurr1);
+ gnext2 = (fcurr2 * (*pk)) + fcurr1;
+
+ /* Read next two samples from input buffer */
+ /* f0(n+2) = x(n+2) */
+ fcurr3 = *pSrc++;
+ fcurr4 = *pSrc++;
+
+ /* Copy only last input samples into the state buffer
+ which will be used for next four samples processing */
+ *px++ = fcurr4;
+
+ /* Process third sample for first tap */
+ fnext3 = fcurr3 + ((*pk) * fcurr2);
+ gnext3 = (fcurr3 * (*pk)) + fcurr2;
+
+ /* Process fourth sample for first tap */
+ fnext4 = fcurr4 + ((*pk) * fcurr3);
+ gnext4 = (fcurr4 * (*pk++)) + fcurr3;
+
+ /* Update of f values for next coefficient set processing */
+ fcurr1 = fnext1;
+ fcurr2 = fnext2;
+ fcurr3 = fnext3;
+ fcurr4 = fnext4;
+
+ /* Loop unrolling. Process 4 taps at a time . */
+ stageCnt = (numStages - 1U) >> 2U;
+
+ /* Loop over the number of taps. Unroll by a factor of 4.
+ ** Repeat until we've computed numStages-3 coefficients. */
+
+ /* Process 2nd, 3rd, 4th and 5th taps ... here */
+ while (stageCnt > 0U)
+ {
+ /* Read g1(n-1), g3(n-1) .... from state */
+ gcurr1 = *px;
+
+ /* save g1(n) in state buffer */
+ *px++ = gnext4;
+
+ /* Process first sample for 2nd, 6th .. tap */
+ /* Sample processing for K2, K6.... */
+ /* f2(n) = f1(n) + K2 * g1(n-1) */
+ fnext1 = fcurr1 + ((*pk) * gcurr1);
+ /* Process second sample for 2nd, 6th .. tap */
+ /* for sample 2 processing */
+ fnext2 = fcurr2 + ((*pk) * gnext1);
+ /* Process third sample for 2nd, 6th .. tap */
+ fnext3 = fcurr3 + ((*pk) * gnext2);
+ /* Process fourth sample for 2nd, 6th .. tap */
+ fnext4 = fcurr4 + ((*pk) * gnext3);
+
+ /* g2(n) = f1(n) * K2 + g1(n-1) */
+ /* Calculation of state values for next stage */
+ gnext4 = (fcurr4 * (*pk)) + gnext3;
+ gnext3 = (fcurr3 * (*pk)) + gnext2;
+ gnext2 = (fcurr2 * (*pk)) + gnext1;
+ gnext1 = (fcurr1 * (*pk++)) + gcurr1;
+
+
+ /* Read g2(n-1), g4(n-1) .... from state */
+ gcurr1 = *px;
+
+ /* save g2(n) in state buffer */
+ *px++ = gnext4;
+
+ /* Sample processing for K3, K7.... */
+ /* Process first sample for 3rd, 7th .. tap */
+ /* f3(n) = f2(n) + K3 * g2(n-1) */
+ fcurr1 = fnext1 + ((*pk) * gcurr1);
+ /* Process second sample for 3rd, 7th .. tap */
+ fcurr2 = fnext2 + ((*pk) * gnext1);
+ /* Process third sample for 3rd, 7th .. tap */
+ fcurr3 = fnext3 + ((*pk) * gnext2);
+ /* Process fourth sample for 3rd, 7th .. tap */
+ fcurr4 = fnext4 + ((*pk) * gnext3);
+
+ /* Calculation of state values for next stage */
+ /* g3(n) = f2(n) * K3 + g2(n-1) */
+ gnext4 = (fnext4 * (*pk)) + gnext3;
+ gnext3 = (fnext3 * (*pk)) + gnext2;
+ gnext2 = (fnext2 * (*pk)) + gnext1;
+ gnext1 = (fnext1 * (*pk++)) + gcurr1;
+
+
+ /* Read g1(n-1), g3(n-1) .... from state */
+ gcurr1 = *px;
+
+ /* save g3(n) in state buffer */
+ *px++ = gnext4;
+
+ /* Sample processing for K4, K8.... */
+ /* Process first sample for 4th, 8th .. tap */
+ /* f4(n) = f3(n) + K4 * g3(n-1) */
+ fnext1 = fcurr1 + ((*pk) * gcurr1);
+ /* Process second sample for 4th, 8th .. tap */
+ /* for sample 2 processing */
+ fnext2 = fcurr2 + ((*pk) * gnext1);
+ /* Process third sample for 4th, 8th .. tap */
+ fnext3 = fcurr3 + ((*pk) * gnext2);
+ /* Process fourth sample for 4th, 8th .. tap */
+ fnext4 = fcurr4 + ((*pk) * gnext3);
+
+ /* g4(n) = f3(n) * K4 + g3(n-1) */
+ /* Calculation of state values for next stage */
+ gnext4 = (fcurr4 * (*pk)) + gnext3;
+ gnext3 = (fcurr3 * (*pk)) + gnext2;
+ gnext2 = (fcurr2 * (*pk)) + gnext1;
+ gnext1 = (fcurr1 * (*pk++)) + gcurr1;
+
+ /* Read g2(n-1), g4(n-1) .... from state */
+ gcurr1 = *px;
+
+ /* save g4(n) in state buffer */
+ *px++ = gnext4;
+
+ /* Sample processing for K5, K9.... */
+ /* Process first sample for 5th, 9th .. tap */
+ /* f5(n) = f4(n) + K5 * g4(n-1) */
+ fcurr1 = fnext1 + ((*pk) * gcurr1);
+ /* Process second sample for 5th, 9th .. tap */
+ fcurr2 = fnext2 + ((*pk) * gnext1);
+ /* Process third sample for 5th, 9th .. tap */
+ fcurr3 = fnext3 + ((*pk) * gnext2);
+ /* Process fourth sample for 5th, 9th .. tap */
+ fcurr4 = fnext4 + ((*pk) * gnext3);
+
+ /* Calculation of state values for next stage */
+ /* g5(n) = f4(n) * K5 + g4(n-1) */
+ gnext4 = (fnext4 * (*pk)) + gnext3;
+ gnext3 = (fnext3 * (*pk)) + gnext2;
+ gnext2 = (fnext2 * (*pk)) + gnext1;
+ gnext1 = (fnext1 * (*pk++)) + gcurr1;
+
+ stageCnt--;
+ }
+
+ /* If the (filter length -1) is not a multiple of 4, compute the remaining filter taps */
+ stageCnt = (numStages - 1U) % 0x4U;
+
+ while (stageCnt > 0U)
+ {
+ gcurr1 = *px;
+
+ /* save g value in state buffer */
+ *px++ = gnext4;
+
+ /* Process four samples for last three taps here */
+ fnext1 = fcurr1 + ((*pk) * gcurr1);
+ fnext2 = fcurr2 + ((*pk) * gnext1);
+ fnext3 = fcurr3 + ((*pk) * gnext2);
+ fnext4 = fcurr4 + ((*pk) * gnext3);
+
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext4 = (fcurr4 * (*pk)) + gnext3;
+ gnext3 = (fcurr3 * (*pk)) + gnext2;
+ gnext2 = (fcurr2 * (*pk)) + gnext1;
+ gnext1 = (fcurr1 * (*pk++)) + gcurr1;
+
+ /* Update of f values for next coefficient set processing */
+ fcurr1 = fnext1;
+ fcurr2 = fnext2;
+ fcurr3 = fnext3;
+ fcurr4 = fnext4;
+
+ stageCnt--;
+
+ }
+
+ /* The results in the 4 accumulators, store in the destination buffer. */
+ /* y(n) = fN(n) */
+ *pDst++ = fcurr1;
+ *pDst++ = fcurr2;
+ *pDst++ = fcurr3;
+ *pDst++ = fcurr4;
+
+ blkCnt--;
+ }
+
+ /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
+ ** No loop unrolling is used. */
+ blkCnt = blockSize % 0x4U;
+
+ while (blkCnt > 0U)
+ {
+ /* f0(n) = x(n) */
+ fcurr1 = *pSrc++;
+
+ /* Initialize coeff pointer */
+ pk = (pCoeffs);
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* read g2(n) from state buffer */
+ gcurr1 = *px;
+
+ /* for sample 1 processing */
+ /* f1(n) = f0(n) + K1 * g0(n-1) */
+ fnext1 = fcurr1 + ((*pk) * gcurr1);
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext1 = (fcurr1 * (*pk++)) + gcurr1;
+
+ /* save g1(n) in state buffer */
+ *px++ = fcurr1;
+
+ /* f1(n) is saved in fcurr1
+ for next stage processing */
+ fcurr1 = fnext1;
+
+ stageCnt = (numStages - 1U);
+
+ /* stage loop */
+ while (stageCnt > 0U)
+ {
+ /* read g2(n) from state buffer */
+ gcurr1 = *px;
+
+ /* save g1(n) in state buffer */
+ *px++ = gnext1;
+
+ /* Sample processing for K2, K3.... */
+ /* f2(n) = f1(n) + K2 * g1(n-1) */
+ fnext1 = fcurr1 + ((*pk) * gcurr1);
+ /* g2(n) = f1(n) * K2 + g1(n-1) */
+ gnext1 = (fcurr1 * (*pk++)) + gcurr1;
+
+ /* f1(n) is saved in fcurr1
+ for next stage processing */
+ fcurr1 = fnext1;
+
+ stageCnt--;
+
+ }
+
+ /* y(n) = fN(n) */
+ *pDst++ = fcurr1;
+
+ blkCnt--;
+
+ }
+
+#else
+
+ /* Run the below code for Cortex-M0 */
+
+ float32_t fcurr, fnext, gcurr, gnext; /* temporary variables */
+ uint32_t numStages = S->numStages; /* Length of the filter */
+ uint32_t blkCnt, stageCnt; /* temporary variables for counts */
+
+ pState = &S->pState[0];
+
+ blkCnt = blockSize;
+
+ while (blkCnt > 0U)
+ {
+ /* f0(n) = x(n) */
+ fcurr = *pSrc++;
+
+ /* Initialize coeff pointer */
+ pk = pCoeffs;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* read g0(n-1) from state buffer */
+ gcurr = *px;
+
+ /* for sample 1 processing */
+ /* f1(n) = f0(n) + K1 * g0(n-1) */
+ fnext = fcurr + ((*pk) * gcurr);
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext = (fcurr * (*pk++)) + gcurr;
+
+ /* save f0(n) in state buffer */
+ *px++ = fcurr;
+
+ /* f1(n) is saved in fcurr
+ for next stage processing */
+ fcurr = fnext;
+
+ stageCnt = (numStages - 1U);
+
+ /* stage loop */
+ while (stageCnt > 0U)
+ {
+ /* read g2(n) from state buffer */
+ gcurr = *px;
+
+ /* save g1(n) in state buffer */
+ *px++ = gnext;
+
+ /* Sample processing for K2, K3.... */
+ /* f2(n) = f1(n) + K2 * g1(n-1) */
+ fnext = fcurr + ((*pk) * gcurr);
+ /* g2(n) = f1(n) * K2 + g1(n-1) */
+ gnext = (fcurr * (*pk++)) + gcurr;
+
+ /* f1(n) is saved in fcurr1
+ for next stage processing */
+ fcurr = fnext;
+
+ stageCnt--;
+
+ }
+
+ /* y(n) = fN(n) */
+ *pDst++ = fcurr;
+
+ blkCnt--;
+
+ }
+
+#endif /* #if defined (ARM_MATH_DSP) */
+
+}
+
+/**
+ * @} end of FIR_Lattice group
+ */
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