diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_q31.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_q31.c | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_q31.c b/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_q31.c new file mode 100644 index 0000000..9d29295 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_lattice_q31.c @@ -0,0 +1,505 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_fir_lattice_q31.c
+ * Description: Q31 FIR lattice filter processing 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"
+
+/**
+ @ingroup groupFilters
+ */
+
+/**
+ @addtogroup FIR_Lattice
+ @{
+ */
+
+/**
+ @brief Processing function for the Q31 FIR lattice filter.
+ @param[in] S points to an instance of the Q31 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
+
+ @par Scaling and Overflow Behavior
+ In order to avoid overflows the input signal must be scaled down by 2*log2(numStages) bits.
+ */
+
+void arm_fir_lattice_q31(
+ const arm_fir_lattice_instance_q31 * S,
+ const q31_t * pSrc,
+ q31_t * pDst,
+ uint32_t blockSize)
+{
+ q31_t *pState = S->pState; /* State pointer */
+ const q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
+ q31_t *px; /* Temporary state pointer */
+ const q31_t *pk; /* Temporary coefficient pointer */
+ uint32_t numStages = S->numStages; /* Number of stages in the filter */
+ uint32_t blkCnt, stageCnt; /* Loop counters */
+ q31_t fcurr0, fnext0, gnext0, gcurr0; /* Temporary variables */
+
+#if (1)
+//#if !defined(ARM_MATH_CM0_FAMILY)
+
+#if defined (ARM_MATH_LOOPUNROLL)
+ q31_t fcurr1, fnext1, gnext1; /* Temporary variables for second sample in loop unrolling */
+ q31_t fcurr2, fnext2, gnext2; /* Temporary variables for third sample in loop unrolling */
+ q31_t fcurr3, fnext3, gnext3; /* Temporary variables for fourth sample in loop unrolling */
+#endif
+
+ gcurr0 = 0;
+
+#if defined (ARM_MATH_LOOPUNROLL)
+
+ /* Loop unrolling: Compute 4 outputs at a time */
+ blkCnt = blockSize >> 2U;
+
+ while (blkCnt > 0U)
+ {
+ /* Read two samples from input buffer */
+ /* f0(n) = x(n) */
+ fcurr0 = *pSrc++;
+ fcurr1 = *pSrc++;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize coeff pointer */
+ pk = pCoeffs;
+
+ /* Read g0(n-1) from state buffer */
+ gcurr0 = *px;
+
+ /* Process first sample for first tap */
+ /* f1(n) = f0(n) + K1 * g0(n-1) */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext0 << 1U) + fcurr0;
+
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* Process second sample for first tap */
+ fnext1 = (q31_t) (((q63_t) fcurr0 * (*pk)) >> 32U);
+ fnext1 = (fnext1 << 1U) + fcurr1;
+ gnext1 = (q31_t) (((q63_t) fcurr1 * (*pk)) >> 32U);
+ gnext1 = (gnext1 << 1U) + fcurr0;
+
+ /* Read next two samples from input buffer */
+ /* f0(n+2) = x(n+2) */
+ fcurr2 = *pSrc++;
+ fcurr3 = *pSrc++;
+
+ /* Process third sample for first tap */
+ fnext2 = (q31_t) (((q63_t) fcurr1 * (*pk)) >> 32U);
+ fnext2 = (fnext2 << 1U) + fcurr2;
+ gnext2 = (q31_t) (((q63_t) fcurr2 * (*pk)) >> 32U);
+ gnext2 = (gnext2 << 1U) + fcurr1;
+
+ /* Process fourth sample for first tap */
+ fnext3 = (q31_t) (((q63_t) fcurr2 * (*pk )) >> 32U);
+ fnext3 = (fnext3 << 1U) + fcurr3;
+ gnext3 = (q31_t) (((q63_t) fcurr3 * (*pk++)) >> 32U);
+ gnext3 = (gnext3 << 1U) + fcurr2;
+
+ /* Copy only last input sample into the state buffer
+ which will be used for next samples processing */
+ *px++ = fcurr3;
+
+ /* Update of f values for next coefficient set processing */
+ fcurr0 = fnext0;
+ fcurr1 = fnext1;
+ fcurr2 = fnext2;
+ fcurr3 = fnext3;
+
+ /* 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 */
+ gcurr0 = *px;
+
+ /* save g1(n) in state buffer */
+ *px++ = gnext3;
+
+ /* Process first sample for 2nd, 6th .. tap */
+ /* Sample processing for K2, K6.... */
+ /* f1(n) = f0(n) + K1 * g0(n-1) */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext0 << 1U) + fcurr0;
+
+ /* Process second sample for 2nd, 6th .. tap */
+ /* for sample 2 processing */
+ fnext1 = (q31_t) (((q63_t) gnext0 * (*pk)) >> 32U);
+ fnext1 = (fnext1 << 1U) + fcurr1;
+
+ /* Process third sample for 2nd, 6th .. tap */
+ fnext2 = (q31_t) (((q63_t) gnext1 * (*pk)) >> 32U);
+ fnext2 = (fnext2 << 1U) + fcurr2;
+
+ /* Process fourth sample for 2nd, 6th .. tap */
+ fnext3 = (q31_t) (((q63_t) gnext2 * (*pk)) >> 32U);
+ fnext3 = (fnext3 << 1U) + fcurr3;
+
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ /* Calculation of state values for next stage */
+ gnext3 = (q31_t) (((q63_t) fcurr3 * (*pk)) >> 32U);
+ gnext3 = (gnext3 << 1U) + gnext2;
+
+ gnext2 = (q31_t) (((q63_t) fcurr2 * (*pk)) >> 32U);
+ gnext2 = (gnext2 << 1U) + gnext1;
+
+ gnext1 = (q31_t) (((q63_t) fcurr1 * (*pk)) >> 32U);
+ gnext1 = (gnext1 << 1U) + gnext0;
+
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+
+ /* Read g2(n-1), g4(n-1) .... from state */
+ gcurr0 = *px;
+
+ /* save g1(n) in state buffer */
+ *px++ = gnext3;
+
+ /* Sample processing for K3, K7.... */
+ /* Process first sample for 3rd, 7th .. tap */
+ /* f3(n) = f2(n) + K3 * g2(n-1) */
+ fcurr0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fcurr0 = (fcurr0 << 1U) + fnext0;
+
+ /* Process second sample for 3rd, 7th .. tap */
+ fcurr1 = (q31_t) (((q63_t) gnext0 * (*pk)) >> 32U);
+ fcurr1 = (fcurr1 << 1U) + fnext1;
+
+ /* Process third sample for 3rd, 7th .. tap */
+ fcurr2 = (q31_t) (((q63_t) gnext1 * (*pk)) >> 32U);
+ fcurr2 = (fcurr2 << 1U) + fnext2;
+
+ /* Process fourth sample for 3rd, 7th .. tap */
+ fcurr3 = (q31_t) (((q63_t) gnext2 * (*pk)) >> 32U);
+ fcurr3 = (fcurr3 << 1U) + fnext3;
+
+ /* Calculation of state values for next stage */
+ /* g3(n) = f2(n) * K3 + g2(n-1) */
+ gnext3 = (q31_t) (((q63_t) fnext3 * (*pk)) >> 32U);
+ gnext3 = (gnext3 << 1U) + gnext2;
+
+ gnext2 = (q31_t) (((q63_t) fnext2 * (*pk)) >> 32U);
+ gnext2 = (gnext2 << 1U) + gnext1;
+
+ gnext1 = (q31_t) (((q63_t) fnext1 * (*pk)) >> 32U);
+ gnext1 = (gnext1 << 1U) + gnext0;
+
+ gnext0 = (q31_t) (((q63_t) fnext0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* Read g1(n-1), g3(n-1) .... from state */
+ gcurr0 = *px;
+
+ /* save g1(n) in state buffer */
+ *px++ = gnext3;
+
+ /* Sample processing for K4, K8.... */
+ /* Process first sample for 4th, 8th .. tap */
+ /* f4(n) = f3(n) + K4 * g3(n-1) */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext0 << 1U) + fcurr0;
+
+ /* Process second sample for 4th, 8th .. tap */
+ /* for sample 2 processing */
+ fnext1 = (q31_t) (((q63_t) gnext0 * (*pk)) >> 32U);
+ fnext1 = (fnext1 << 1U) + fcurr1;
+
+ /* Process third sample for 4th, 8th .. tap */
+ fnext2 = (q31_t) (((q63_t) gnext1 * (*pk)) >> 32U);
+ fnext2 = (fnext2 << 1U) + fcurr2;
+
+ /* Process fourth sample for 4th, 8th .. tap */
+ fnext3 = (q31_t) (((q63_t) gnext2 * (*pk)) >> 32U);
+ fnext3 = (fnext3 << 1U) + fcurr3;
+
+ /* g4(n) = f3(n) * K4 + g3(n-1) */
+ /* Calculation of state values for next stage */
+ gnext3 = (q31_t) (((q63_t) fcurr3 * (*pk)) >> 32U);
+ gnext3 = (gnext3 << 1U) + gnext2;
+
+ gnext2 = (q31_t) (((q63_t) fcurr2 * (*pk)) >> 32U);
+ gnext2 = (gnext2 << 1U) + gnext1;
+
+ gnext1 = (q31_t) (((q63_t) fcurr1 * (*pk)) >> 32U);
+ gnext1 = (gnext1 << 1U) + gnext0;
+
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* Read g2(n-1), g4(n-1) .... from state */
+ gcurr0 = *px;
+
+ /* save g4(n) in state buffer */
+ *px++ = gnext3;
+
+ /* Sample processing for K5, K9.... */
+ /* Process first sample for 5th, 9th .. tap */
+ /* f5(n) = f4(n) + K5 * g4(n-1) */
+ fcurr0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fcurr0 = (fcurr0 << 1U) + fnext0;
+
+ /* Process second sample for 5th, 9th .. tap */
+ fcurr1 = (q31_t) (((q63_t) gnext0 * (*pk)) >> 32U);
+ fcurr1 = (fcurr1 << 1U) + fnext1;
+
+ /* Process third sample for 5th, 9th .. tap */
+ fcurr2 = (q31_t) (((q63_t) gnext1 * (*pk)) >> 32U);
+ fcurr2 = (fcurr2 << 1U) + fnext2;
+
+ /* Process fourth sample for 5th, 9th .. tap */
+ fcurr3 = (q31_t) (((q63_t) gnext2 * (*pk)) >> 32U);
+ fcurr3 = (fcurr3 << 1U) + fnext3;
+
+ /* Calculation of state values for next stage */
+ /* g5(n) = f4(n) * K5 + g4(n-1) */
+ gnext3 = (q31_t) (((q63_t) fnext3 * (*pk)) >> 32U);
+ gnext3 = (gnext3 << 1U) + gnext2;
+
+ gnext2 = (q31_t) (((q63_t) fnext2 * (*pk)) >> 32U);
+ gnext2 = (gnext2 << 1U) + gnext1;
+
+ gnext1 = (q31_t) (((q63_t) fnext1 * (*pk)) >> 32U);
+ gnext1 = (gnext1 << 1U) + gnext0;
+
+ gnext0 = (q31_t) (((q63_t) fnext0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ stageCnt--;
+ }
+
+ /* If the (filter length -1) is not a multiple of 4, compute the remaining filter taps */
+ stageCnt = (numStages - 1U) % 0x4U;
+
+ while (stageCnt > 0U)
+ {
+ gcurr0 = *px;
+
+ /* save g value in state buffer */
+ *px++ = gnext3;
+
+ /* Process four samples for last three taps here */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext0 << 1U) + fcurr0;
+
+ fnext1 = (q31_t) (((q63_t) gnext0 * (*pk)) >> 32U);
+ fnext1 = (fnext1 << 1U) + fcurr1;
+
+ fnext2 = (q31_t) (((q63_t) gnext1 * (*pk)) >> 32U);
+ fnext2 = (fnext2 << 1U) + fcurr2;
+
+ fnext3 = (q31_t) (((q63_t) gnext2 * (*pk)) >> 32U);
+ fnext3 = (fnext3 << 1U) + fcurr3;
+
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext3 = (q31_t) (((q63_t) fcurr3 * (*pk)) >> 32U);
+ gnext3 = (gnext3 << 1U) + gnext2;
+
+ gnext2 = (q31_t) (((q63_t) fcurr2 * (*pk)) >> 32U);
+ gnext2 = (gnext2 << 1U) + gnext1;
+
+ gnext1 = (q31_t) (((q63_t) fcurr1 * (*pk)) >> 32U);
+ gnext1 = (gnext1 << 1U) + gnext0;
+
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* Update of f values for next coefficient set processing */
+ fcurr0 = fnext0;
+ fcurr1 = fnext1;
+ fcurr2 = fnext2;
+ fcurr3 = fnext3;
+
+ stageCnt--;
+ }
+
+ /* The results in the 4 accumulators, store in the destination buffer. */
+ /* y(n) = fN(n) */
+ *pDst++ = fcurr0;
+ *pDst++ = fcurr1;
+ *pDst++ = fcurr2;
+ *pDst++ = fcurr3;
+
+ blkCnt--;
+ }
+
+ /* Loop unrolling: Compute remaining outputs */
+ blkCnt = blockSize % 0x4U;
+
+#else
+
+ /* Initialize blkCnt with number of samples */
+ blkCnt = blockSize;
+
+#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
+
+ while (blkCnt > 0U)
+ {
+ /* f0(n) = x(n) */
+ fcurr0 = *pSrc++;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize coeff pointer */
+ pk = pCoeffs;
+
+ /* read g2(n) from state buffer */
+ gcurr0 = *px;
+
+ /* for sample 1 processing */
+ /* f1(n) = f0(n) + K1 * g0(n-1) */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext0 << 1U) + fcurr0;
+
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* save g1(n) in state buffer */
+ *px++ = fcurr0;
+
+ /* f1(n) is saved in fcurr0 for next stage processing */
+ fcurr0 = fnext0;
+
+ stageCnt = (numStages - 1U);
+
+ /* stage loop */
+ while (stageCnt > 0U)
+ {
+ /* read g2(n) from state buffer */
+ gcurr0 = *px;
+
+ /* save g1(n) in state buffer */
+ *px++ = gnext0;
+
+ /* Sample processing for K2, K3.... */
+ /* f2(n) = f1(n) + K2 * g1(n-1) */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext0 << 1U) + fcurr0;
+
+ /* g2(n) = f1(n) * K2 + g1(n-1) */
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* f1(n) is saved in fcurr0 for next stage processing */
+ fcurr0 = fnext0;
+
+ stageCnt--;
+ }
+
+ /* y(n) = fN(n) */
+ *pDst++ = fcurr0;
+
+ blkCnt--;
+ }
+
+#else
+/* alternate version for CM0_FAMILY */
+
+ blkCnt = blockSize;
+
+ while (blkCnt > 0U)
+ {
+ /* f0(n) = x(n) */
+ fcurr0 = *pSrc++;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize coeff pointer */
+ pk = pCoeffs;
+
+ /* read g0(n-1) from state buffer */
+ gcurr0 = *px;
+
+ /* for sample 1 processing */
+ /* f1(n) = f0(n) + K1 * g0(n-1) */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext << 1U) + fcurr0;
+
+ /* g1(n) = f0(n) * K1 + g0(n-1) */
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* save f0(n) in state buffer */
+ *px++ = fcurr0;
+
+ /* f1(n) is saved in fcurr for next stage processing */
+ fcurr0 = fnext0;
+
+ stageCnt = (numStages - 1U);
+
+ /* stage loop */
+ while (stageCnt > 0U)
+ {
+ /* read g1(n-1) from state buffer */
+ gcurr0 = *px;
+
+ /* save g0(n-1) in state buffer */
+ *px++ = gnext0;
+
+ /* Sample processing for K2, K3.... */
+ /* f2(n) = f1(n) + K2 * g1(n-1) */
+ fnext0 = (q31_t) (((q63_t) gcurr0 * (*pk)) >> 32U);
+ fnext0 = (fnext0 << 1U) + fcurr0;
+
+ /* g2(n) = f1(n) * K2 + g1(n-1) */
+ gnext0 = (q31_t) (((q63_t) fcurr0 * (*pk++)) >> 32U);
+ gnext0 = (gnext0 << 1U) + gcurr0;
+
+ /* f1(n) is saved in fcurr0 for next stage processing */
+ fcurr0 = fnext0;
+
+ stageCnt--;
+ }
+
+ /* y(n) = fN(n) */
+ *pDst++ = fcurr0;
+
+ blkCnt--;
+ }
+
+#endif /* #if !defined(ARM_MATH_CM0_FAMILY) */
+
+}
+
+/**
+ @} end of FIR_Lattice group
+ */
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