1 files changed, 102 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal_f16.c b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal_f16.c
new file mode 100644
index 0000000..2e64636
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+++ b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal_f16.c
@@ -0,0 +1,102 @@
+/* ----------------------------------------------------------------------
+ * Project:      CMSIS DSP Library
+ * Title:        arm_bitreversal_f16.c
+ * Description:  Bitreversal functions
+ *
+ * $Date:        23 April 2021
+ * $Revision:    V1.9.0
+ *
+ * Target Processor: Cortex-M and Cortex-A cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2021 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 "dsp/transform_functions_f16.h"
+
+/*
+* @brief  In-place bit reversal function.
+* @param[in, out] *pSrc        points to the in-place buffer of floating-point data type.
+* @param[in]      fftSize      length of the FFT.
+* @param[in]      bitRevFactor bit reversal modifier that supports different size FFTs with the same bit reversal table.
+* @param[in]      *pBitRevTab  points to the bit reversal table.
+* @return none.
+*/
+
+#if defined(ARM_FLOAT16_SUPPORTED)
+
+void arm_bitreversal_f16(
+float16_t * pSrc,
+uint16_t fftSize,
+uint16_t bitRevFactor,
+const uint16_t * pBitRevTab)
+{
+   uint16_t fftLenBy2, fftLenBy2p1;
+   uint16_t i, j;
+   float16_t in;
+
+   /*  Initializations */
+   j = 0U;
+   fftLenBy2 = fftSize >> 1U;
+   fftLenBy2p1 = (fftSize >> 1U) + 1U;
+
+   /* Bit Reversal Implementation */
+   for (i = 0U; i <= (fftLenBy2 - 2U); i += 2U)
+   {
+      if (i < j)
+      {
+         /*  pSrc[i] <-> pSrc[j]; */
+         in = pSrc[2U * i];
+         pSrc[2U * i] = pSrc[2U * j];
+         pSrc[2U * j] = in;
+
+         /*  pSrc[i+1U] <-> pSrc[j+1U] */
+         in = pSrc[(2U * i) + 1U];
+         pSrc[(2U * i) + 1U] = pSrc[(2U * j) + 1U];
+         pSrc[(2U * j) + 1U] = in;
+
+         /*  pSrc[i+fftLenBy2p1] <-> pSrc[j+fftLenBy2p1] */
+         in = pSrc[2U * (i + fftLenBy2p1)];
+         pSrc[2U * (i + fftLenBy2p1)] = pSrc[2U * (j + fftLenBy2p1)];
+         pSrc[2U * (j + fftLenBy2p1)] = in;
+
+         /*  pSrc[i+fftLenBy2p1+1U] <-> pSrc[j+fftLenBy2p1+1U] */
+         in = pSrc[(2U * (i + fftLenBy2p1)) + 1U];
+         pSrc[(2U * (i + fftLenBy2p1)) + 1U] =
+         pSrc[(2U * (j + fftLenBy2p1)) + 1U];
+         pSrc[(2U * (j + fftLenBy2p1)) + 1U] = in;
+
+      }
+
+      /*  pSrc[i+1U] <-> pSrc[j+1U] */
+      in = pSrc[2U * (i + 1U)];
+      pSrc[2U * (i + 1U)] = pSrc[2U * (j + fftLenBy2)];
+      pSrc[2U * (j + fftLenBy2)] = in;
+
+      /*  pSrc[i+2U] <-> pSrc[j+2U] */
+      in = pSrc[(2U * (i + 1U)) + 1U];
+      pSrc[(2U * (i + 1U)) + 1U] = pSrc[(2U * (j + fftLenBy2)) + 1U];
+      pSrc[(2U * (j + fftLenBy2)) + 1U] = in;
+
+      /*  Reading the index for the bit reversal */
+      j = *pBitRevTab;
+
+      /*  Updating the bit reversal index depending on the fft length  */
+      pBitRevTab += bitRevFactor;
+   }
+}
+#endif /* #if defined(ARM_FLOAT16_SUPPORTED) */