CMSIS DSP library
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cmsis_dsp/FilteringFunctions/arm_iir_lattice_q15.c@5:3762170b6d4d, 2015-11-20 (annotated)
- Committer:
- mbed_official
- Date:
- Fri Nov 20 08:45:18 2015 +0000
- Revision:
- 5:3762170b6d4d
- Parent:
- 3:7a284390b0ce
Synchronized with git revision 2eb940b9a73af188d3004a2575fdfbb05febe62b
Full URL: https://github.com/mbedmicro/mbed/commit/2eb940b9a73af188d3004a2575fdfbb05febe62b/
Added option to build rpc library. closes #1426
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
emilmont | 1:fdd22bb7aa52 | 1 | /* ---------------------------------------------------------------------- |
mbed_official | 5:3762170b6d4d | 2 | * Copyright (C) 2010-2014 ARM Limited. All rights reserved. |
emilmont | 1:fdd22bb7aa52 | 3 | * |
mbed_official | 5:3762170b6d4d | 4 | * $Date: 19. March 2015 |
mbed_official | 5:3762170b6d4d | 5 | * $Revision: V.1.4.5 |
emilmont | 1:fdd22bb7aa52 | 6 | * |
emilmont | 2:da51fb522205 | 7 | * Project: CMSIS DSP Library |
emilmont | 2:da51fb522205 | 8 | * Title: arm_iir_lattice_q15.c |
emilmont | 1:fdd22bb7aa52 | 9 | * |
emilmont | 2:da51fb522205 | 10 | * Description: Q15 IIR lattice filter processing function. |
emilmont | 1:fdd22bb7aa52 | 11 | * |
emilmont | 1:fdd22bb7aa52 | 12 | * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 |
emilmont | 1:fdd22bb7aa52 | 13 | * |
mbed_official | 3:7a284390b0ce | 14 | * Redistribution and use in source and binary forms, with or without |
mbed_official | 3:7a284390b0ce | 15 | * modification, are permitted provided that the following conditions |
mbed_official | 3:7a284390b0ce | 16 | * are met: |
mbed_official | 3:7a284390b0ce | 17 | * - Redistributions of source code must retain the above copyright |
mbed_official | 3:7a284390b0ce | 18 | * notice, this list of conditions and the following disclaimer. |
mbed_official | 3:7a284390b0ce | 19 | * - Redistributions in binary form must reproduce the above copyright |
mbed_official | 3:7a284390b0ce | 20 | * notice, this list of conditions and the following disclaimer in |
mbed_official | 3:7a284390b0ce | 21 | * the documentation and/or other materials provided with the |
mbed_official | 3:7a284390b0ce | 22 | * distribution. |
mbed_official | 3:7a284390b0ce | 23 | * - Neither the name of ARM LIMITED nor the names of its contributors |
mbed_official | 3:7a284390b0ce | 24 | * may be used to endorse or promote products derived from this |
mbed_official | 3:7a284390b0ce | 25 | * software without specific prior written permission. |
mbed_official | 3:7a284390b0ce | 26 | * |
mbed_official | 3:7a284390b0ce | 27 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
mbed_official | 3:7a284390b0ce | 28 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
mbed_official | 3:7a284390b0ce | 29 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
mbed_official | 3:7a284390b0ce | 30 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
mbed_official | 3:7a284390b0ce | 31 | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
mbed_official | 3:7a284390b0ce | 32 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
mbed_official | 3:7a284390b0ce | 33 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
mbed_official | 3:7a284390b0ce | 34 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
mbed_official | 3:7a284390b0ce | 35 | * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
mbed_official | 3:7a284390b0ce | 36 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN |
mbed_official | 3:7a284390b0ce | 37 | * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
mbed_official | 3:7a284390b0ce | 38 | * POSSIBILITY OF SUCH DAMAGE. |
emilmont | 1:fdd22bb7aa52 | 39 | * -------------------------------------------------------------------- */ |
emilmont | 1:fdd22bb7aa52 | 40 | |
emilmont | 1:fdd22bb7aa52 | 41 | #include "arm_math.h" |
emilmont | 1:fdd22bb7aa52 | 42 | |
emilmont | 1:fdd22bb7aa52 | 43 | /** |
emilmont | 1:fdd22bb7aa52 | 44 | * @ingroup groupFilters |
emilmont | 1:fdd22bb7aa52 | 45 | */ |
emilmont | 1:fdd22bb7aa52 | 46 | |
emilmont | 1:fdd22bb7aa52 | 47 | /** |
emilmont | 1:fdd22bb7aa52 | 48 | * @addtogroup IIR_Lattice |
emilmont | 1:fdd22bb7aa52 | 49 | * @{ |
emilmont | 1:fdd22bb7aa52 | 50 | */ |
emilmont | 1:fdd22bb7aa52 | 51 | |
emilmont | 1:fdd22bb7aa52 | 52 | /** |
emilmont | 1:fdd22bb7aa52 | 53 | * @brief Processing function for the Q15 IIR lattice filter. |
emilmont | 1:fdd22bb7aa52 | 54 | * @param[in] *S points to an instance of the Q15 IIR lattice structure. |
emilmont | 1:fdd22bb7aa52 | 55 | * @param[in] *pSrc points to the block of input data. |
emilmont | 1:fdd22bb7aa52 | 56 | * @param[out] *pDst points to the block of output data. |
emilmont | 1:fdd22bb7aa52 | 57 | * @param[in] blockSize number of samples to process. |
emilmont | 1:fdd22bb7aa52 | 58 | * @return none. |
emilmont | 1:fdd22bb7aa52 | 59 | * |
emilmont | 1:fdd22bb7aa52 | 60 | * @details |
emilmont | 1:fdd22bb7aa52 | 61 | * <b>Scaling and Overflow Behavior:</b> |
emilmont | 1:fdd22bb7aa52 | 62 | * \par |
emilmont | 1:fdd22bb7aa52 | 63 | * The function is implemented using a 64-bit internal accumulator. |
emilmont | 1:fdd22bb7aa52 | 64 | * Both coefficients and state variables are represented in 1.15 format and multiplications yield a 2.30 result. |
emilmont | 1:fdd22bb7aa52 | 65 | * The 2.30 intermediate results are accumulated in a 64-bit accumulator in 34.30 format. |
emilmont | 1:fdd22bb7aa52 | 66 | * There is no risk of internal overflow with this approach and the full precision of intermediate multiplications is preserved. |
emilmont | 1:fdd22bb7aa52 | 67 | * After all additions have been performed, the accumulator is truncated to 34.15 format by discarding low 15 bits. |
emilmont | 1:fdd22bb7aa52 | 68 | * Lastly, the accumulator is saturated to yield a result in 1.15 format. |
emilmont | 1:fdd22bb7aa52 | 69 | */ |
emilmont | 1:fdd22bb7aa52 | 70 | |
emilmont | 1:fdd22bb7aa52 | 71 | void arm_iir_lattice_q15( |
emilmont | 1:fdd22bb7aa52 | 72 | const arm_iir_lattice_instance_q15 * S, |
emilmont | 1:fdd22bb7aa52 | 73 | q15_t * pSrc, |
emilmont | 1:fdd22bb7aa52 | 74 | q15_t * pDst, |
emilmont | 1:fdd22bb7aa52 | 75 | uint32_t blockSize) |
emilmont | 1:fdd22bb7aa52 | 76 | { |
emilmont | 1:fdd22bb7aa52 | 77 | |
emilmont | 1:fdd22bb7aa52 | 78 | |
mbed_official | 3:7a284390b0ce | 79 | #ifndef ARM_MATH_CM0_FAMILY |
emilmont | 1:fdd22bb7aa52 | 80 | |
emilmont | 1:fdd22bb7aa52 | 81 | /* Run the below code for Cortex-M4 and Cortex-M3 */ |
emilmont | 1:fdd22bb7aa52 | 82 | |
emilmont | 1:fdd22bb7aa52 | 83 | q31_t fcurr, fnext, gcurr = 0, gnext; /* Temporary variables for lattice stages */ |
emilmont | 1:fdd22bb7aa52 | 84 | q15_t gnext1, gnext2; /* Temporary variables for lattice stages */ |
emilmont | 1:fdd22bb7aa52 | 85 | uint32_t stgCnt; /* Temporary variables for counts */ |
emilmont | 1:fdd22bb7aa52 | 86 | q63_t acc; /* Accumlator */ |
emilmont | 1:fdd22bb7aa52 | 87 | uint32_t blkCnt, tapCnt; /* Temporary variables for counts */ |
emilmont | 1:fdd22bb7aa52 | 88 | q15_t *px1, *px2, *pk, *pv; /* temporary pointers for state and coef */ |
emilmont | 1:fdd22bb7aa52 | 89 | uint32_t numStages = S->numStages; /* number of stages */ |
emilmont | 1:fdd22bb7aa52 | 90 | q15_t *pState; /* State pointer */ |
emilmont | 1:fdd22bb7aa52 | 91 | q15_t *pStateCurnt; /* State current pointer */ |
emilmont | 1:fdd22bb7aa52 | 92 | q15_t out; /* Temporary variable for output */ |
mbed_official | 3:7a284390b0ce | 93 | q31_t v; /* Temporary variable for ladder coefficient */ |
emilmont | 1:fdd22bb7aa52 | 94 | #ifdef UNALIGNED_SUPPORT_DISABLE |
mbed_official | 3:7a284390b0ce | 95 | q15_t v1, v2; |
emilmont | 1:fdd22bb7aa52 | 96 | #endif |
emilmont | 1:fdd22bb7aa52 | 97 | |
emilmont | 1:fdd22bb7aa52 | 98 | |
emilmont | 1:fdd22bb7aa52 | 99 | blkCnt = blockSize; |
emilmont | 1:fdd22bb7aa52 | 100 | |
emilmont | 1:fdd22bb7aa52 | 101 | pState = &S->pState[0]; |
emilmont | 1:fdd22bb7aa52 | 102 | |
emilmont | 1:fdd22bb7aa52 | 103 | /* Sample processing */ |
emilmont | 1:fdd22bb7aa52 | 104 | while(blkCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 105 | { |
emilmont | 1:fdd22bb7aa52 | 106 | /* Read Sample from input buffer */ |
emilmont | 1:fdd22bb7aa52 | 107 | /* fN(n) = x(n) */ |
emilmont | 1:fdd22bb7aa52 | 108 | fcurr = *pSrc++; |
emilmont | 1:fdd22bb7aa52 | 109 | |
emilmont | 1:fdd22bb7aa52 | 110 | /* Initialize state read pointer */ |
emilmont | 1:fdd22bb7aa52 | 111 | px1 = pState; |
emilmont | 1:fdd22bb7aa52 | 112 | /* Initialize state write pointer */ |
emilmont | 1:fdd22bb7aa52 | 113 | px2 = pState; |
emilmont | 1:fdd22bb7aa52 | 114 | /* Set accumulator to zero */ |
emilmont | 1:fdd22bb7aa52 | 115 | acc = 0; |
emilmont | 1:fdd22bb7aa52 | 116 | /* Initialize Ladder coeff pointer */ |
emilmont | 1:fdd22bb7aa52 | 117 | pv = &S->pvCoeffs[0]; |
emilmont | 1:fdd22bb7aa52 | 118 | /* Initialize Reflection coeff pointer */ |
emilmont | 1:fdd22bb7aa52 | 119 | pk = &S->pkCoeffs[0]; |
emilmont | 1:fdd22bb7aa52 | 120 | |
emilmont | 1:fdd22bb7aa52 | 121 | |
emilmont | 1:fdd22bb7aa52 | 122 | /* Process sample for first tap */ |
emilmont | 1:fdd22bb7aa52 | 123 | gcurr = *px1++; |
emilmont | 1:fdd22bb7aa52 | 124 | /* fN-1(n) = fN(n) - kN * gN-1(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 125 | fnext = fcurr - (((q31_t) gcurr * (*pk)) >> 15); |
emilmont | 1:fdd22bb7aa52 | 126 | fnext = __SSAT(fnext, 16); |
emilmont | 1:fdd22bb7aa52 | 127 | /* gN(n) = kN * fN-1(n) + gN-1(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 128 | gnext = (((q31_t) fnext * (*pk++)) >> 15) + gcurr; |
emilmont | 1:fdd22bb7aa52 | 129 | gnext = __SSAT(gnext, 16); |
emilmont | 1:fdd22bb7aa52 | 130 | /* write gN(n) into state for next sample processing */ |
emilmont | 1:fdd22bb7aa52 | 131 | *px2++ = (q15_t) gnext; |
emilmont | 1:fdd22bb7aa52 | 132 | /* y(n) += gN(n) * vN */ |
emilmont | 1:fdd22bb7aa52 | 133 | acc += (q31_t) ((gnext * (*pv++))); |
emilmont | 1:fdd22bb7aa52 | 134 | |
emilmont | 1:fdd22bb7aa52 | 135 | |
emilmont | 1:fdd22bb7aa52 | 136 | /* Update f values for next coefficient processing */ |
emilmont | 1:fdd22bb7aa52 | 137 | fcurr = fnext; |
emilmont | 1:fdd22bb7aa52 | 138 | |
emilmont | 1:fdd22bb7aa52 | 139 | /* Loop unrolling. Process 4 taps at a time. */ |
emilmont | 1:fdd22bb7aa52 | 140 | tapCnt = (numStages - 1u) >> 2; |
emilmont | 1:fdd22bb7aa52 | 141 | |
emilmont | 1:fdd22bb7aa52 | 142 | while(tapCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 143 | { |
emilmont | 1:fdd22bb7aa52 | 144 | |
emilmont | 1:fdd22bb7aa52 | 145 | /* Process sample for 2nd, 6th ...taps */ |
emilmont | 1:fdd22bb7aa52 | 146 | /* Read gN-2(n-1) from state buffer */ |
emilmont | 1:fdd22bb7aa52 | 147 | gcurr = *px1++; |
emilmont | 1:fdd22bb7aa52 | 148 | /* Process sample for 2nd, 6th .. taps */ |
emilmont | 1:fdd22bb7aa52 | 149 | /* fN-2(n) = fN-1(n) - kN-1 * gN-2(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 150 | fnext = fcurr - (((q31_t) gcurr * (*pk)) >> 15); |
emilmont | 1:fdd22bb7aa52 | 151 | fnext = __SSAT(fnext, 16); |
emilmont | 1:fdd22bb7aa52 | 152 | /* gN-1(n) = kN-1 * fN-2(n) + gN-2(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 153 | gnext = (((q31_t) fnext * (*pk++)) >> 15) + gcurr; |
emilmont | 1:fdd22bb7aa52 | 154 | gnext1 = (q15_t) __SSAT(gnext, 16); |
emilmont | 1:fdd22bb7aa52 | 155 | /* write gN-1(n) into state */ |
emilmont | 1:fdd22bb7aa52 | 156 | *px2++ = (q15_t) gnext1; |
emilmont | 1:fdd22bb7aa52 | 157 | |
emilmont | 1:fdd22bb7aa52 | 158 | |
emilmont | 1:fdd22bb7aa52 | 159 | /* Process sample for 3nd, 7th ...taps */ |
emilmont | 1:fdd22bb7aa52 | 160 | /* Read gN-3(n-1) from state */ |
emilmont | 1:fdd22bb7aa52 | 161 | gcurr = *px1++; |
emilmont | 1:fdd22bb7aa52 | 162 | /* Process sample for 3rd, 7th .. taps */ |
emilmont | 1:fdd22bb7aa52 | 163 | /* fN-3(n) = fN-2(n) - kN-2 * gN-3(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 164 | fcurr = fnext - (((q31_t) gcurr * (*pk)) >> 15); |
emilmont | 1:fdd22bb7aa52 | 165 | fcurr = __SSAT(fcurr, 16); |
emilmont | 1:fdd22bb7aa52 | 166 | /* gN-2(n) = kN-2 * fN-3(n) + gN-3(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 167 | gnext = (((q31_t) fcurr * (*pk++)) >> 15) + gcurr; |
emilmont | 1:fdd22bb7aa52 | 168 | gnext2 = (q15_t) __SSAT(gnext, 16); |
emilmont | 1:fdd22bb7aa52 | 169 | /* write gN-2(n) into state */ |
emilmont | 1:fdd22bb7aa52 | 170 | *px2++ = (q15_t) gnext2; |
emilmont | 1:fdd22bb7aa52 | 171 | |
emilmont | 1:fdd22bb7aa52 | 172 | /* Read vN-1 and vN-2 at a time */ |
emilmont | 1:fdd22bb7aa52 | 173 | #ifndef UNALIGNED_SUPPORT_DISABLE |
emilmont | 1:fdd22bb7aa52 | 174 | |
emilmont | 1:fdd22bb7aa52 | 175 | v = *__SIMD32(pv)++; |
emilmont | 1:fdd22bb7aa52 | 176 | |
emilmont | 1:fdd22bb7aa52 | 177 | #else |
emilmont | 1:fdd22bb7aa52 | 178 | |
emilmont | 2:da51fb522205 | 179 | v1 = *pv++; |
emilmont | 2:da51fb522205 | 180 | v2 = *pv++; |
emilmont | 1:fdd22bb7aa52 | 181 | |
emilmont | 1:fdd22bb7aa52 | 182 | #ifndef ARM_MATH_BIG_ENDIAN |
emilmont | 1:fdd22bb7aa52 | 183 | |
emilmont | 2:da51fb522205 | 184 | v = __PKHBT(v1, v2, 16); |
emilmont | 1:fdd22bb7aa52 | 185 | |
emilmont | 1:fdd22bb7aa52 | 186 | #else |
emilmont | 1:fdd22bb7aa52 | 187 | |
emilmont | 2:da51fb522205 | 188 | v = __PKHBT(v2, v1, 16); |
emilmont | 1:fdd22bb7aa52 | 189 | |
emilmont | 2:da51fb522205 | 190 | #endif /* #ifndef ARM_MATH_BIG_ENDIAN */ |
emilmont | 1:fdd22bb7aa52 | 191 | |
emilmont | 2:da51fb522205 | 192 | #endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */ |
emilmont | 1:fdd22bb7aa52 | 193 | |
emilmont | 1:fdd22bb7aa52 | 194 | |
emilmont | 1:fdd22bb7aa52 | 195 | /* Pack gN-1(n) and gN-2(n) */ |
emilmont | 1:fdd22bb7aa52 | 196 | |
emilmont | 1:fdd22bb7aa52 | 197 | #ifndef ARM_MATH_BIG_ENDIAN |
emilmont | 1:fdd22bb7aa52 | 198 | |
emilmont | 1:fdd22bb7aa52 | 199 | gnext = __PKHBT(gnext1, gnext2, 16); |
emilmont | 1:fdd22bb7aa52 | 200 | |
emilmont | 1:fdd22bb7aa52 | 201 | #else |
emilmont | 1:fdd22bb7aa52 | 202 | |
emilmont | 1:fdd22bb7aa52 | 203 | gnext = __PKHBT(gnext2, gnext1, 16); |
emilmont | 1:fdd22bb7aa52 | 204 | |
emilmont | 1:fdd22bb7aa52 | 205 | #endif /* #ifndef ARM_MATH_BIG_ENDIAN */ |
emilmont | 1:fdd22bb7aa52 | 206 | |
emilmont | 1:fdd22bb7aa52 | 207 | /* y(n) += gN-1(n) * vN-1 */ |
emilmont | 1:fdd22bb7aa52 | 208 | /* process for gN-5(n) * vN-5, gN-9(n) * vN-9 ... */ |
emilmont | 1:fdd22bb7aa52 | 209 | /* y(n) += gN-2(n) * vN-2 */ |
emilmont | 1:fdd22bb7aa52 | 210 | /* process for gN-6(n) * vN-6, gN-10(n) * vN-10 ... */ |
emilmont | 1:fdd22bb7aa52 | 211 | acc = __SMLALD(gnext, v, acc); |
emilmont | 1:fdd22bb7aa52 | 212 | |
emilmont | 1:fdd22bb7aa52 | 213 | |
emilmont | 1:fdd22bb7aa52 | 214 | /* Process sample for 4th, 8th ...taps */ |
emilmont | 1:fdd22bb7aa52 | 215 | /* Read gN-4(n-1) from state */ |
emilmont | 1:fdd22bb7aa52 | 216 | gcurr = *px1++; |
emilmont | 1:fdd22bb7aa52 | 217 | /* Process sample for 4th, 8th .. taps */ |
emilmont | 1:fdd22bb7aa52 | 218 | /* fN-4(n) = fN-3(n) - kN-3 * gN-4(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 219 | fnext = fcurr - (((q31_t) gcurr * (*pk)) >> 15); |
emilmont | 1:fdd22bb7aa52 | 220 | fnext = __SSAT(fnext, 16); |
emilmont | 1:fdd22bb7aa52 | 221 | /* gN-3(n) = kN-3 * fN-1(n) + gN-1(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 222 | gnext = (((q31_t) fnext * (*pk++)) >> 15) + gcurr; |
emilmont | 1:fdd22bb7aa52 | 223 | gnext1 = (q15_t) __SSAT(gnext, 16); |
emilmont | 1:fdd22bb7aa52 | 224 | /* write gN-3(n) for the next sample process */ |
emilmont | 1:fdd22bb7aa52 | 225 | *px2++ = (q15_t) gnext1; |
emilmont | 1:fdd22bb7aa52 | 226 | |
emilmont | 1:fdd22bb7aa52 | 227 | |
emilmont | 1:fdd22bb7aa52 | 228 | /* Process sample for 5th, 9th ...taps */ |
emilmont | 1:fdd22bb7aa52 | 229 | /* Read gN-5(n-1) from state */ |
emilmont | 1:fdd22bb7aa52 | 230 | gcurr = *px1++; |
emilmont | 1:fdd22bb7aa52 | 231 | /* Process sample for 5th, 9th .. taps */ |
emilmont | 1:fdd22bb7aa52 | 232 | /* fN-5(n) = fN-4(n) - kN-4 * gN-5(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 233 | fcurr = fnext - (((q31_t) gcurr * (*pk)) >> 15); |
emilmont | 1:fdd22bb7aa52 | 234 | fcurr = __SSAT(fcurr, 16); |
emilmont | 1:fdd22bb7aa52 | 235 | /* gN-4(n) = kN-4 * fN-5(n) + gN-5(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 236 | gnext = (((q31_t) fcurr * (*pk++)) >> 15) + gcurr; |
emilmont | 1:fdd22bb7aa52 | 237 | gnext2 = (q15_t) __SSAT(gnext, 16); |
emilmont | 1:fdd22bb7aa52 | 238 | /* write gN-4(n) for the next sample process */ |
emilmont | 1:fdd22bb7aa52 | 239 | *px2++ = (q15_t) gnext2; |
emilmont | 1:fdd22bb7aa52 | 240 | |
emilmont | 1:fdd22bb7aa52 | 241 | /* Read vN-3 and vN-4 at a time */ |
emilmont | 1:fdd22bb7aa52 | 242 | #ifndef UNALIGNED_SUPPORT_DISABLE |
emilmont | 1:fdd22bb7aa52 | 243 | |
emilmont | 1:fdd22bb7aa52 | 244 | v = *__SIMD32(pv)++; |
emilmont | 1:fdd22bb7aa52 | 245 | |
emilmont | 1:fdd22bb7aa52 | 246 | #else |
emilmont | 1:fdd22bb7aa52 | 247 | |
emilmont | 2:da51fb522205 | 248 | v1 = *pv++; |
emilmont | 2:da51fb522205 | 249 | v2 = *pv++; |
emilmont | 1:fdd22bb7aa52 | 250 | |
emilmont | 1:fdd22bb7aa52 | 251 | #ifndef ARM_MATH_BIG_ENDIAN |
emilmont | 1:fdd22bb7aa52 | 252 | |
emilmont | 2:da51fb522205 | 253 | v = __PKHBT(v1, v2, 16); |
emilmont | 1:fdd22bb7aa52 | 254 | |
emilmont | 1:fdd22bb7aa52 | 255 | #else |
emilmont | 1:fdd22bb7aa52 | 256 | |
emilmont | 2:da51fb522205 | 257 | v = __PKHBT(v2, v1, 16); |
emilmont | 1:fdd22bb7aa52 | 258 | |
emilmont | 2:da51fb522205 | 259 | #endif /* #ifndef ARM_MATH_BIG_ENDIAN */ |
emilmont | 1:fdd22bb7aa52 | 260 | |
emilmont | 2:da51fb522205 | 261 | #endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */ |
emilmont | 1:fdd22bb7aa52 | 262 | |
emilmont | 1:fdd22bb7aa52 | 263 | |
emilmont | 1:fdd22bb7aa52 | 264 | /* Pack gN-3(n) and gN-4(n) */ |
emilmont | 1:fdd22bb7aa52 | 265 | #ifndef ARM_MATH_BIG_ENDIAN |
emilmont | 1:fdd22bb7aa52 | 266 | |
emilmont | 1:fdd22bb7aa52 | 267 | gnext = __PKHBT(gnext1, gnext2, 16); |
emilmont | 1:fdd22bb7aa52 | 268 | |
emilmont | 1:fdd22bb7aa52 | 269 | #else |
emilmont | 1:fdd22bb7aa52 | 270 | |
emilmont | 1:fdd22bb7aa52 | 271 | gnext = __PKHBT(gnext2, gnext1, 16); |
emilmont | 1:fdd22bb7aa52 | 272 | |
emilmont | 1:fdd22bb7aa52 | 273 | #endif /* #ifndef ARM_MATH_BIG_ENDIAN */ |
emilmont | 1:fdd22bb7aa52 | 274 | |
emilmont | 1:fdd22bb7aa52 | 275 | /* y(n) += gN-4(n) * vN-4 */ |
emilmont | 1:fdd22bb7aa52 | 276 | /* process for gN-8(n) * vN-8, gN-12(n) * vN-12 ... */ |
emilmont | 1:fdd22bb7aa52 | 277 | /* y(n) += gN-3(n) * vN-3 */ |
emilmont | 1:fdd22bb7aa52 | 278 | /* process for gN-7(n) * vN-7, gN-11(n) * vN-11 ... */ |
emilmont | 1:fdd22bb7aa52 | 279 | acc = __SMLALD(gnext, v, acc); |
emilmont | 1:fdd22bb7aa52 | 280 | |
emilmont | 1:fdd22bb7aa52 | 281 | tapCnt--; |
emilmont | 1:fdd22bb7aa52 | 282 | |
emilmont | 1:fdd22bb7aa52 | 283 | } |
emilmont | 1:fdd22bb7aa52 | 284 | |
emilmont | 1:fdd22bb7aa52 | 285 | fnext = fcurr; |
emilmont | 1:fdd22bb7aa52 | 286 | |
emilmont | 1:fdd22bb7aa52 | 287 | /* If the filter length is not a multiple of 4, compute the remaining filter taps */ |
emilmont | 1:fdd22bb7aa52 | 288 | tapCnt = (numStages - 1u) % 0x4u; |
emilmont | 1:fdd22bb7aa52 | 289 | |
emilmont | 1:fdd22bb7aa52 | 290 | while(tapCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 291 | { |
emilmont | 1:fdd22bb7aa52 | 292 | gcurr = *px1++; |
emilmont | 1:fdd22bb7aa52 | 293 | /* Process sample for last taps */ |
emilmont | 1:fdd22bb7aa52 | 294 | fnext = fcurr - (((q31_t) gcurr * (*pk)) >> 15); |
emilmont | 1:fdd22bb7aa52 | 295 | fnext = __SSAT(fnext, 16); |
emilmont | 1:fdd22bb7aa52 | 296 | gnext = (((q31_t) fnext * (*pk++)) >> 15) + gcurr; |
emilmont | 1:fdd22bb7aa52 | 297 | gnext = __SSAT(gnext, 16); |
emilmont | 1:fdd22bb7aa52 | 298 | /* Output samples for last taps */ |
emilmont | 1:fdd22bb7aa52 | 299 | acc += (q31_t) (((q31_t) gnext * (*pv++))); |
emilmont | 1:fdd22bb7aa52 | 300 | *px2++ = (q15_t) gnext; |
emilmont | 1:fdd22bb7aa52 | 301 | fcurr = fnext; |
emilmont | 1:fdd22bb7aa52 | 302 | |
emilmont | 1:fdd22bb7aa52 | 303 | tapCnt--; |
emilmont | 1:fdd22bb7aa52 | 304 | } |
emilmont | 1:fdd22bb7aa52 | 305 | |
emilmont | 1:fdd22bb7aa52 | 306 | /* y(n) += g0(n) * v0 */ |
emilmont | 1:fdd22bb7aa52 | 307 | acc += (q31_t) (((q31_t) fnext * (*pv++))); |
emilmont | 1:fdd22bb7aa52 | 308 | |
emilmont | 1:fdd22bb7aa52 | 309 | out = (q15_t) __SSAT(acc >> 15, 16); |
emilmont | 1:fdd22bb7aa52 | 310 | *px2++ = (q15_t) fnext; |
emilmont | 1:fdd22bb7aa52 | 311 | |
emilmont | 1:fdd22bb7aa52 | 312 | /* write out into pDst */ |
emilmont | 1:fdd22bb7aa52 | 313 | *pDst++ = out; |
emilmont | 1:fdd22bb7aa52 | 314 | |
emilmont | 1:fdd22bb7aa52 | 315 | /* Advance the state pointer by 4 to process the next group of 4 samples */ |
emilmont | 1:fdd22bb7aa52 | 316 | pState = pState + 1u; |
emilmont | 1:fdd22bb7aa52 | 317 | blkCnt--; |
emilmont | 1:fdd22bb7aa52 | 318 | |
emilmont | 1:fdd22bb7aa52 | 319 | } |
emilmont | 1:fdd22bb7aa52 | 320 | |
emilmont | 1:fdd22bb7aa52 | 321 | /* Processing is complete. Now copy last S->numStages samples to start of the buffer |
emilmont | 1:fdd22bb7aa52 | 322 | for the preperation of next frame process */ |
emilmont | 1:fdd22bb7aa52 | 323 | /* Points to the start of the state buffer */ |
emilmont | 1:fdd22bb7aa52 | 324 | pStateCurnt = &S->pState[0]; |
emilmont | 1:fdd22bb7aa52 | 325 | pState = &S->pState[blockSize]; |
emilmont | 1:fdd22bb7aa52 | 326 | |
emilmont | 1:fdd22bb7aa52 | 327 | stgCnt = (numStages >> 2u); |
emilmont | 1:fdd22bb7aa52 | 328 | |
emilmont | 1:fdd22bb7aa52 | 329 | /* copy data */ |
emilmont | 1:fdd22bb7aa52 | 330 | while(stgCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 331 | { |
emilmont | 1:fdd22bb7aa52 | 332 | #ifndef UNALIGNED_SUPPORT_DISABLE |
emilmont | 1:fdd22bb7aa52 | 333 | |
emilmont | 1:fdd22bb7aa52 | 334 | *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++; |
emilmont | 1:fdd22bb7aa52 | 335 | *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++; |
emilmont | 1:fdd22bb7aa52 | 336 | |
emilmont | 1:fdd22bb7aa52 | 337 | #else |
emilmont | 1:fdd22bb7aa52 | 338 | |
emilmont | 1:fdd22bb7aa52 | 339 | *pStateCurnt++ = *pState++; |
emilmont | 1:fdd22bb7aa52 | 340 | *pStateCurnt++ = *pState++; |
emilmont | 1:fdd22bb7aa52 | 341 | *pStateCurnt++ = *pState++; |
emilmont | 1:fdd22bb7aa52 | 342 | *pStateCurnt++ = *pState++; |
emilmont | 1:fdd22bb7aa52 | 343 | |
emilmont | 2:da51fb522205 | 344 | #endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */ |
emilmont | 1:fdd22bb7aa52 | 345 | |
emilmont | 1:fdd22bb7aa52 | 346 | /* Decrement the loop counter */ |
emilmont | 1:fdd22bb7aa52 | 347 | stgCnt--; |
emilmont | 1:fdd22bb7aa52 | 348 | |
emilmont | 1:fdd22bb7aa52 | 349 | } |
emilmont | 1:fdd22bb7aa52 | 350 | |
emilmont | 1:fdd22bb7aa52 | 351 | /* Calculation of count for remaining q15_t data */ |
emilmont | 1:fdd22bb7aa52 | 352 | stgCnt = (numStages) % 0x4u; |
emilmont | 1:fdd22bb7aa52 | 353 | |
emilmont | 1:fdd22bb7aa52 | 354 | /* copy data */ |
emilmont | 1:fdd22bb7aa52 | 355 | while(stgCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 356 | { |
emilmont | 1:fdd22bb7aa52 | 357 | *pStateCurnt++ = *pState++; |
emilmont | 1:fdd22bb7aa52 | 358 | |
emilmont | 1:fdd22bb7aa52 | 359 | /* Decrement the loop counter */ |
emilmont | 1:fdd22bb7aa52 | 360 | stgCnt--; |
emilmont | 1:fdd22bb7aa52 | 361 | } |
emilmont | 1:fdd22bb7aa52 | 362 | |
emilmont | 1:fdd22bb7aa52 | 363 | #else |
emilmont | 1:fdd22bb7aa52 | 364 | |
emilmont | 1:fdd22bb7aa52 | 365 | /* Run the below code for Cortex-M0 */ |
emilmont | 1:fdd22bb7aa52 | 366 | |
emilmont | 1:fdd22bb7aa52 | 367 | q31_t fcurr, fnext = 0, gcurr = 0, gnext; /* Temporary variables for lattice stages */ |
emilmont | 1:fdd22bb7aa52 | 368 | uint32_t stgCnt; /* Temporary variables for counts */ |
emilmont | 1:fdd22bb7aa52 | 369 | q63_t acc; /* Accumlator */ |
emilmont | 1:fdd22bb7aa52 | 370 | uint32_t blkCnt, tapCnt; /* Temporary variables for counts */ |
emilmont | 1:fdd22bb7aa52 | 371 | q15_t *px1, *px2, *pk, *pv; /* temporary pointers for state and coef */ |
emilmont | 1:fdd22bb7aa52 | 372 | uint32_t numStages = S->numStages; /* number of stages */ |
emilmont | 1:fdd22bb7aa52 | 373 | q15_t *pState; /* State pointer */ |
emilmont | 1:fdd22bb7aa52 | 374 | q15_t *pStateCurnt; /* State current pointer */ |
emilmont | 1:fdd22bb7aa52 | 375 | q15_t out; /* Temporary variable for output */ |
emilmont | 1:fdd22bb7aa52 | 376 | |
emilmont | 1:fdd22bb7aa52 | 377 | |
emilmont | 1:fdd22bb7aa52 | 378 | blkCnt = blockSize; |
emilmont | 1:fdd22bb7aa52 | 379 | |
emilmont | 1:fdd22bb7aa52 | 380 | pState = &S->pState[0]; |
emilmont | 1:fdd22bb7aa52 | 381 | |
emilmont | 1:fdd22bb7aa52 | 382 | /* Sample processing */ |
emilmont | 1:fdd22bb7aa52 | 383 | while(blkCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 384 | { |
emilmont | 1:fdd22bb7aa52 | 385 | /* Read Sample from input buffer */ |
emilmont | 1:fdd22bb7aa52 | 386 | /* fN(n) = x(n) */ |
emilmont | 1:fdd22bb7aa52 | 387 | fcurr = *pSrc++; |
emilmont | 1:fdd22bb7aa52 | 388 | |
emilmont | 1:fdd22bb7aa52 | 389 | /* Initialize state read pointer */ |
emilmont | 1:fdd22bb7aa52 | 390 | px1 = pState; |
emilmont | 1:fdd22bb7aa52 | 391 | /* Initialize state write pointer */ |
emilmont | 1:fdd22bb7aa52 | 392 | px2 = pState; |
emilmont | 1:fdd22bb7aa52 | 393 | /* Set accumulator to zero */ |
emilmont | 1:fdd22bb7aa52 | 394 | acc = 0; |
emilmont | 1:fdd22bb7aa52 | 395 | /* Initialize Ladder coeff pointer */ |
emilmont | 1:fdd22bb7aa52 | 396 | pv = &S->pvCoeffs[0]; |
emilmont | 1:fdd22bb7aa52 | 397 | /* Initialize Reflection coeff pointer */ |
emilmont | 1:fdd22bb7aa52 | 398 | pk = &S->pkCoeffs[0]; |
emilmont | 1:fdd22bb7aa52 | 399 | |
emilmont | 1:fdd22bb7aa52 | 400 | tapCnt = numStages; |
emilmont | 1:fdd22bb7aa52 | 401 | |
emilmont | 1:fdd22bb7aa52 | 402 | while(tapCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 403 | { |
emilmont | 1:fdd22bb7aa52 | 404 | gcurr = *px1++; |
emilmont | 1:fdd22bb7aa52 | 405 | /* Process sample */ |
emilmont | 1:fdd22bb7aa52 | 406 | /* fN-1(n) = fN(n) - kN * gN-1(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 407 | fnext = fcurr - ((gcurr * (*pk)) >> 15); |
emilmont | 1:fdd22bb7aa52 | 408 | fnext = __SSAT(fnext, 16); |
emilmont | 1:fdd22bb7aa52 | 409 | /* gN(n) = kN * fN-1(n) + gN-1(n-1) */ |
emilmont | 1:fdd22bb7aa52 | 410 | gnext = ((fnext * (*pk++)) >> 15) + gcurr; |
emilmont | 1:fdd22bb7aa52 | 411 | gnext = __SSAT(gnext, 16); |
emilmont | 1:fdd22bb7aa52 | 412 | /* Output samples */ |
emilmont | 1:fdd22bb7aa52 | 413 | /* y(n) += gN(n) * vN */ |
emilmont | 1:fdd22bb7aa52 | 414 | acc += (q31_t) ((gnext * (*pv++))); |
emilmont | 1:fdd22bb7aa52 | 415 | /* write gN(n) into state for next sample processing */ |
emilmont | 1:fdd22bb7aa52 | 416 | *px2++ = (q15_t) gnext; |
emilmont | 1:fdd22bb7aa52 | 417 | /* Update f values for next coefficient processing */ |
emilmont | 1:fdd22bb7aa52 | 418 | fcurr = fnext; |
emilmont | 1:fdd22bb7aa52 | 419 | |
emilmont | 1:fdd22bb7aa52 | 420 | tapCnt--; |
emilmont | 1:fdd22bb7aa52 | 421 | } |
emilmont | 1:fdd22bb7aa52 | 422 | |
emilmont | 1:fdd22bb7aa52 | 423 | /* y(n) += g0(n) * v0 */ |
emilmont | 1:fdd22bb7aa52 | 424 | acc += (q31_t) ((fnext * (*pv++))); |
emilmont | 1:fdd22bb7aa52 | 425 | |
emilmont | 1:fdd22bb7aa52 | 426 | out = (q15_t) __SSAT(acc >> 15, 16); |
emilmont | 1:fdd22bb7aa52 | 427 | *px2++ = (q15_t) fnext; |
emilmont | 1:fdd22bb7aa52 | 428 | |
emilmont | 1:fdd22bb7aa52 | 429 | /* write out into pDst */ |
emilmont | 1:fdd22bb7aa52 | 430 | *pDst++ = out; |
emilmont | 1:fdd22bb7aa52 | 431 | |
emilmont | 1:fdd22bb7aa52 | 432 | /* Advance the state pointer by 1 to process the next group of samples */ |
emilmont | 1:fdd22bb7aa52 | 433 | pState = pState + 1u; |
emilmont | 1:fdd22bb7aa52 | 434 | blkCnt--; |
emilmont | 1:fdd22bb7aa52 | 435 | |
emilmont | 1:fdd22bb7aa52 | 436 | } |
emilmont | 1:fdd22bb7aa52 | 437 | |
emilmont | 1:fdd22bb7aa52 | 438 | /* Processing is complete. Now copy last S->numStages samples to start of the buffer |
emilmont | 1:fdd22bb7aa52 | 439 | for the preperation of next frame process */ |
emilmont | 1:fdd22bb7aa52 | 440 | /* Points to the start of the state buffer */ |
emilmont | 1:fdd22bb7aa52 | 441 | pStateCurnt = &S->pState[0]; |
emilmont | 1:fdd22bb7aa52 | 442 | pState = &S->pState[blockSize]; |
emilmont | 1:fdd22bb7aa52 | 443 | |
emilmont | 1:fdd22bb7aa52 | 444 | stgCnt = numStages; |
emilmont | 1:fdd22bb7aa52 | 445 | |
emilmont | 1:fdd22bb7aa52 | 446 | /* copy data */ |
emilmont | 1:fdd22bb7aa52 | 447 | while(stgCnt > 0u) |
emilmont | 1:fdd22bb7aa52 | 448 | { |
emilmont | 1:fdd22bb7aa52 | 449 | *pStateCurnt++ = *pState++; |
emilmont | 1:fdd22bb7aa52 | 450 | |
emilmont | 1:fdd22bb7aa52 | 451 | /* Decrement the loop counter */ |
emilmont | 1:fdd22bb7aa52 | 452 | stgCnt--; |
emilmont | 1:fdd22bb7aa52 | 453 | } |
emilmont | 1:fdd22bb7aa52 | 454 | |
mbed_official | 3:7a284390b0ce | 455 | #endif /* #ifndef ARM_MATH_CM0_FAMILY */ |
emilmont | 1:fdd22bb7aa52 | 456 | |
emilmont | 1:fdd22bb7aa52 | 457 | } |
emilmont | 1:fdd22bb7aa52 | 458 | |
emilmont | 1:fdd22bb7aa52 | 459 | |
emilmont | 1:fdd22bb7aa52 | 460 | |
emilmont | 1:fdd22bb7aa52 | 461 | |
emilmont | 1:fdd22bb7aa52 | 462 | /** |
emilmont | 1:fdd22bb7aa52 | 463 | * @} end of IIR_Lattice group |
emilmont | 1:fdd22bb7aa52 | 464 | */ |