69 lines
2.6 KiB
Verilog
69 lines
2.6 KiB
Verilog
// ***************************************************************************
|
|
// ***************************************************************************
|
|
// Copyright (C) 2018-2023 Analog Devices, Inc. All rights reserved.
|
|
//
|
|
// Each core or library found in this collection may have its own licensing terms.
|
|
// The user should keep this in in mind while exploring these cores.
|
|
//
|
|
// Redistribution and use in source and binary forms,
|
|
// with or without modification of this file, are permitted under the terms of either
|
|
// (at the option of the user):
|
|
//
|
|
// 1. The GNU General Public License version 2 as published by the
|
|
// Free Software Foundation, which can be found in the top level directory, or at:
|
|
// https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html
|
|
//
|
|
// OR
|
|
//
|
|
// 2. An ADI specific BSD license as noted in the top level directory, or on-line at:
|
|
// https://github.com/analogdevicesinc/hdl/blob/dev/LICENSE
|
|
//
|
|
// ***************************************************************************
|
|
// ***************************************************************************
|
|
|
|
`timescale 1ns/100ps
|
|
|
|
module ad_perfect_shuffle #(
|
|
parameter NUM_GROUPS = 2,
|
|
parameter WORDS_PER_GROUP = 2,
|
|
parameter WORD_WIDTH = 8
|
|
) (
|
|
input [NUM_GROUPS*WORDS_PER_GROUP*WORD_WIDTH-1:0] data_in,
|
|
output [NUM_GROUPS*WORDS_PER_GROUP*WORD_WIDTH-1:0] data_out
|
|
);
|
|
/*
|
|
* Performs the perfect shuffle operation.
|
|
*
|
|
* The perfect shuffle splits the input vector into NUM_GROUPS groups and then
|
|
* each group in WORDS_PER_GROUP. The output vector consists of WORDS_PER_GROUP
|
|
* groups and each group has NUM_GROUPS words. The data is remapped, so that
|
|
* the i-th word of the j-th word in the output vector is the j-th word of the
|
|
* i-th group of the input vector.
|
|
|
|
* The inverse operation of the perfect shuffle is the perfect shuffle with
|
|
* both parameters swapped.
|
|
* I.e. [perfect_suffle B A [perfect_shuffle A B data]] == data
|
|
*
|
|
* Examples:
|
|
* NUM_GROUPS = 2, WORDS_PER_GROUP = 4
|
|
* [A B C D a b c d] => [A a B b C c D d]
|
|
* NUM_GROUPS = 4, WORDS_PER_GROUP = 2
|
|
* [A a B b C c D d] => [A B C D a b c d]
|
|
* NUM_GROUPS = 3, WORDS_PER_GROUP = 2
|
|
* [A B a b 1 2] => [A a 1 B b 2]
|
|
*/
|
|
generate
|
|
genvar i;
|
|
genvar j;
|
|
for (i = 0; i < NUM_GROUPS; i = i + 1) begin: shuffle_outer
|
|
for (j = 0; j < WORDS_PER_GROUP; j = j + 1) begin: shuffle_inner
|
|
localparam src_lsb = (j + i * WORDS_PER_GROUP) * WORD_WIDTH;
|
|
localparam dst_lsb = (i + j * NUM_GROUPS) * WORD_WIDTH;
|
|
|
|
assign data_out[dst_lsb+:WORD_WIDTH] = data_in[src_lsb+:WORD_WIDTH];
|
|
end
|
|
end
|
|
endgenerate
|
|
|
|
endmodule
|