// SPDX-License-Identifier: BSD-3-Clause

//

// Copyright(c) 2020 Intel Corporation. All rights reserved.

//

// Author: Amery Song <chao.song@intel.com>

// Keyon Jie <yang.jie@linux.intel.com>

#include <sof/audio/buffer.h>

#include <sof/audio/format.h>

#include <sof/common.h>

#include <rtos/alloc.h>

#include <sof/math/fft.h>

struct fft_plan *fft_plan_new(void *inb, void *outb, uint32_t size, int bits)

{

struct fft_plan *plan;

int lim = 1;

int len = 0;

int i;

if (!inb || !outb)

return NULL;

plan = rzalloc(SOF_MEM_ZONE_RUNTIME, 0, SOF_MEM_CAPS_RAM, sizeof(struct fft_plan));

if (!plan)

return NULL;

switch (bits) {

case 16:

plan->inb16 = inb;

plan->outb16 = outb;

break;

case 32:

plan->inb32 = inb;

plan->outb32 = outb;

break;

default:

rfree(plan);

return NULL;

}

/* calculate the exponent of 2 */

while (lim < size) {

lim <<= 1;

len++;

}

plan->size = lim;

plan->len = len;

plan->bit_reverse_idx = rzalloc(SOF_MEM_ZONE_RUNTIME, 0, SOF_MEM_CAPS_RAM,

plan->size * sizeof(uint16_t));

if (!plan->bit_reverse_idx) {

rfree(plan);

return NULL;

}

/* set up the bit reverse index */

for (i = 1; i < plan->size; ++i)

plan->bit_reverse_idx[i] = (plan->bit_reverse_idx[i >> 1] >> 1) |

((i & 1) << (len - 1));

return plan;

}

void fft_plan_free(struct fft_plan *plan)

{

if (!plan)

return;

rfree(plan->bit_reverse_idx);

rfree(plan);

}