1 /* ----------------------------------------------------------------------
2 * Project: CMSIS DSP Library
3 * Title: arm_rfft_init_q31.c
4 * Description: RFFT & RIFFT Q31 initialisation function
5 *
6 * $Date: 23 April 2021
7 * $Revision: V1.9.0
8 *
9 * Target Processor: Cortex-M and Cortex-A cores
10 * -------------------------------------------------------------------- */
11 /*
12 * Copyright (C) 2010-2021 ARM Limited or its affiliates. All rights reserved.
13 *
14 * SPDX-License-Identifier: Apache-2.0
15 *
16 * Licensed under the Apache License, Version 2.0 (the License); you may
17 * not use this file except in compliance with the License.
18 * You may obtain a copy of the License at
19 *
20 * www.apache.org/licenses/LICENSE-2.0
21 *
22 * Unless required by applicable law or agreed to in writing, software
23 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
24 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
25 * See the License for the specific language governing permissions and
26 * limitations under the License.
27 */
28
29 #include "dsp/transform_functions.h"
30 #include "arm_common_tables.h"
31 #include "arm_const_structs.h"
32
33
34
35 /**
36 @addtogroup RealFFT
37 @{
38 */
39
40 /**
41 @brief Initialization function for the Q31 RFFT/RIFFT.
42 @param[in,out] S points to an instance of the Q31 RFFT/RIFFT structure
43 @param[in] fftLenReal length of the FFT
44 @param[in] ifftFlagR flag that selects transform direction
45 - value = 0: forward transform
46 - value = 1: inverse transform
47 @param[in] bitReverseFlag flag that enables / disables bit reversal of output
48 - value = 0: disables bit reversal of output
49 - value = 1: enables bit reversal of output
50 @return execution status
51 - \ref ARM_MATH_SUCCESS : Operation successful
52 - \ref ARM_MATH_ARGUMENT_ERROR : <code>fftLenReal</code> is not a supported length
53
54 @par Details
55 The parameter <code>fftLenReal</code> specifies length of RFFT/RIFFT Process.
56 Supported FFT Lengths are 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192.
57 @par
58 The parameter <code>ifftFlagR</code> controls whether a forward or inverse transform is computed.
59 Set(=1) ifftFlagR to calculate RIFFT, otherwise RFFT is calculated.
60 @par
61 The parameter <code>bitReverseFlag</code> controls whether output is in normal order or bit reversed order.
62 Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
63 @par
64 This function also initializes Twiddle factor table.
65 */
66
arm_rfft_init_q31(arm_rfft_instance_q31 * S,uint32_t fftLenReal,uint32_t ifftFlagR,uint32_t bitReverseFlag)67 arm_status arm_rfft_init_q31(
68 arm_rfft_instance_q31 * S,
69 uint32_t fftLenReal,
70 uint32_t ifftFlagR,
71 uint32_t bitReverseFlag)
72 {
73 /* Initialise the default arm status */
74 arm_status status = ARM_MATH_ARGUMENT_ERROR;
75
76 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_FFT_ALLOW_TABLES)
77
78 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || defined(ARM_TABLE_REALCOEF_Q31)
79
80 /* Initialise the default arm status */
81 status = ARM_MATH_SUCCESS;
82
83 /* Initialize the Real FFT length */
84 S->fftLenReal = (uint16_t) fftLenReal;
85
86 /* Initialize the Twiddle coefficientA pointer */
87 S->pTwiddleAReal = (q31_t *) realCoefAQ31;
88
89 /* Initialize the Twiddle coefficientB pointer */
90 S->pTwiddleBReal = (q31_t *) realCoefBQ31;
91
92 /* Initialize the Flag for selection of RFFT or RIFFT */
93 S->ifftFlagR = (uint8_t) ifftFlagR;
94
95 /* Initialize the Flag for calculation Bit reversal or not */
96 S->bitReverseFlagR = (uint8_t) bitReverseFlag;
97
98 /* Initialization of coef modifier depending on the FFT length */
99 switch (S->fftLenReal)
100 {
101 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_4096) && defined(ARM_TABLE_BITREVIDX_FXT_4096))
102 case 8192U:
103
104
105 S->twidCoefRModifier = 1U;
106
107 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
108 status=arm_cfft_init_q31(&(S->cfftInst),4096);
109 if (status != ARM_MATH_SUCCESS)
110 {
111 return(status);
112 }
113 #else
114 S->pCfft = &arm_cfft_sR_q31_len4096;
115 #endif
116 break;
117 #endif
118 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_2048) && defined(ARM_TABLE_BITREVIDX_FXT_2048))
119 case 4096U:
120 S->twidCoefRModifier = 2U;
121
122 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
123 status=arm_cfft_init_q31(&(S->cfftInst),2048);
124 if (status != ARM_MATH_SUCCESS)
125 {
126 return(status);
127 }
128 #else
129 S->pCfft = &arm_cfft_sR_q31_len2048;
130 #endif
131 break;
132 #endif
133 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_1024) && defined(ARM_TABLE_BITREVIDX_FXT_1024))
134 case 2048U:
135 S->twidCoefRModifier = 4U;
136
137 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
138 status=arm_cfft_init_q31(&(S->cfftInst),1024);
139 if (status != ARM_MATH_SUCCESS)
140 {
141 return(status);
142 }
143 #else
144 S->pCfft = &arm_cfft_sR_q31_len1024;
145 #endif
146 break;
147 #endif
148 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_512) && defined(ARM_TABLE_BITREVIDX_FXT_512))
149 case 1024U:
150 S->twidCoefRModifier = 8U;
151 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
152 status=arm_cfft_init_q31(&(S->cfftInst),512);
153 if (status != ARM_MATH_SUCCESS)
154 {
155 return(status);
156 }
157 #else
158 S->pCfft = &arm_cfft_sR_q31_len512;
159 #endif
160 break;
161 #endif
162 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_256) && defined(ARM_TABLE_BITREVIDX_FXT_256))
163 case 512U:
164 S->twidCoefRModifier = 16U;
165 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
166 status=arm_cfft_init_q31(&(S->cfftInst),256);
167 if (status != ARM_MATH_SUCCESS)
168 {
169 return(status);
170 }
171 #else
172 S->pCfft = &arm_cfft_sR_q31_len256;
173 #endif
174 break;
175 #endif
176 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_128) && defined(ARM_TABLE_BITREVIDX_FXT_128))
177 case 256U:
178 S->twidCoefRModifier = 32U;
179 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
180 status=arm_cfft_init_q31(&(S->cfftInst),128);
181 if (status != ARM_MATH_SUCCESS)
182 {
183 return(status);
184 }
185 #else
186 S->pCfft = &arm_cfft_sR_q31_len128;
187 #endif
188 break;
189 #endif
190 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_64) && defined(ARM_TABLE_BITREVIDX_FXT_64))
191 case 128U:
192 S->twidCoefRModifier = 64U;
193 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
194 status=arm_cfft_init_q31(&(S->cfftInst),64);
195 if (status != ARM_MATH_SUCCESS)
196 {
197 return(status);
198 }
199 #else
200 S->pCfft = &arm_cfft_sR_q31_len64;
201 #endif
202 break;
203 #endif
204 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_32) && defined(ARM_TABLE_BITREVIDX_FXT_32))
205 case 64U:
206 S->twidCoefRModifier = 128U;
207 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
208 status=arm_cfft_init_q31(&(S->cfftInst),32);
209 if (status != ARM_MATH_SUCCESS)
210 {
211 return(status);
212 }
213 #else
214 S->pCfft = &arm_cfft_sR_q31_len32;
215 #endif
216 break;
217 #endif
218 #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q31_16) && defined(ARM_TABLE_BITREVIDX_FXT_16))
219 case 32U:
220 S->twidCoefRModifier = 256U;
221 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
222 status=arm_cfft_init_q31(&(S->cfftInst),16);
223 if (status != ARM_MATH_SUCCESS)
224 {
225 return(status);
226 }
227 #else
228 S->pCfft = &arm_cfft_sR_q31_len16;
229 #endif
230 break;
231 #endif
232 default:
233 /* Reporting argument error if rfftSize is not valid value */
234 status = ARM_MATH_ARGUMENT_ERROR;
235 break;
236 }
237
238 #endif
239 #endif
240 /* return the status of RFFT Init function */
241 return (status);
242 }
243
244 /**
245 @} end of RealFFT group
246 */
247