From 6ab94e0b318884bbcb95e2ea3835f951502e1d99 Mon Sep 17 00:00:00 2001 From: jaseg Date: Wed, 14 Oct 2020 12:47:28 +0200 Subject: Move firmware into subdirectory --- .../DSP/Source/FastMathFunctions/arm_sqrt_q31.c | 142 +++++++++++++++++++++ 1 file changed, 142 insertions(+) create mode 100644 fw/midi-dials/Drivers/CMSIS/DSP/Source/FastMathFunctions/arm_sqrt_q31.c (limited to 'fw/midi-dials/Drivers/CMSIS/DSP/Source/FastMathFunctions/arm_sqrt_q31.c') diff --git a/fw/midi-dials/Drivers/CMSIS/DSP/Source/FastMathFunctions/arm_sqrt_q31.c b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FastMathFunctions/arm_sqrt_q31.c new file mode 100644 index 0000000..de8c35f --- /dev/null +++ b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FastMathFunctions/arm_sqrt_q31.c @@ -0,0 +1,142 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_sqrt_q31.c + * Description: Q31 square root function + * + * $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" +#include "arm_common_tables.h" + +/** + * @ingroup groupFastMath + */ + +/** + * @addtogroup SQRT + * @{ + */ + +/** + * @brief Q31 square root function. + * @param[in] in input value. The range of the input value is [0 +1) or 0x00000000 to 0x7FFFFFFF. + * @param[out] *pOut square root of input value. + * @return The function returns ARM_MATH_SUCCESS if the input value is positive + * and ARM_MATH_ARGUMENT_ERROR if the input is negative. For + * negative inputs, the function returns *pOut = 0. + */ + +arm_status arm_sqrt_q31( + q31_t in, + q31_t * pOut) +{ + q31_t number, temp1, bits_val1, var1, signBits1, half; + float32_t temp_float1; + union + { + q31_t fracval; + float32_t floatval; + } tempconv; + + number = in; + + /* If the input is a positive number then compute the signBits. */ + if (number > 0) + { + signBits1 = __CLZ(number) - 1; + + /* Shift by the number of signBits1 */ + if ((signBits1 % 2) == 0) + { + number = number << signBits1; + } + else + { + number = number << (signBits1 - 1); + } + + /* Calculate half value of the number */ + half = number >> 1; + /* Store the number for later use */ + temp1 = number; + + /*Convert to float */ + temp_float1 = number * 4.6566128731e-010f; + /*Store as integer */ + tempconv.floatval = temp_float1; + bits_val1 = tempconv.fracval; + /* Subtract the shifted value from the magic number to give intial guess */ + bits_val1 = 0x5f3759df - (bits_val1 >> 1); /* gives initial guess */ + /* Store as float */ + tempconv.fracval = bits_val1; + temp_float1 = tempconv.floatval; + /* Convert to integer format */ + var1 = (q31_t) (temp_float1 * 1073741824); + + /* 1st iteration */ + var1 = ((q31_t) ((q63_t) var1 * (0x30000000 - + ((q31_t) + ((((q31_t) + (((q63_t) var1 * var1) >> 31)) * + (q63_t) half) >> 31))) >> 31)) << 2; + /* 2nd iteration */ + var1 = ((q31_t) ((q63_t) var1 * (0x30000000 - + ((q31_t) + ((((q31_t) + (((q63_t) var1 * var1) >> 31)) * + (q63_t) half) >> 31))) >> 31)) << 2; + /* 3rd iteration */ + var1 = ((q31_t) ((q63_t) var1 * (0x30000000 - + ((q31_t) + ((((q31_t) + (((q63_t) var1 * var1) >> 31)) * + (q63_t) half) >> 31))) >> 31)) << 2; + + /* Multiply the inverse square root with the original value */ + var1 = ((q31_t) (((q63_t) temp1 * var1) >> 31)) << 1; + + /* Shift the output down accordingly */ + if ((signBits1 % 2) == 0) + { + var1 = var1 >> (signBits1 / 2); + } + else + { + var1 = var1 >> ((signBits1 - 1) / 2); + } + *pOut = var1; + + return (ARM_MATH_SUCCESS); + } + /* If the number is a negative number then store zero as its square root value */ + else + { + *pOut = 0; + return (ARM_MATH_ARGUMENT_ERROR); + } +} + +/** + * @} end of SQRT group + */ -- cgit