| /******************************************************************************** |
| * Marvell GPL License Option |
| * |
| * If you received this File from Marvell, you may opt to use, redistribute and/or |
| * modify this File in accordance with the terms and conditions of the General |
| * Public License Version 2, June 1991 (the "GPL License"), a copy of which is |
| * available along with the File in the license.txt file or by writing to the Free |
| * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 or |
| * on the worldwide web at http://www.gnu.org/licenses/gpl.txt. |
| * |
| * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY |
| * DISCLAIMED. The GPL License provides additional details about this warranty |
| * disclaimer. |
| ******************************************************************************/ |
| |
| #ifndef _PRBS_H_ |
| #define _PRBS_H_ |
| /** Generate the PRBS (Pseudo Random Binary Sequence). |
| * |
| * It's very simple to use it, just call prbs##_gen(). |
| * |
| * At present, it supports the follow PRBS. |
| * - PRBS-15: x^15 + x^14 + 1 (0xC001), Period 2^15 - 1 (32767) bits |
| * - PRBS-23: x^23 + x^18 + 1 (0x84001), Period 2^23 -1 (8388607) bits - TODO |
| * - PRBS-32: x^31 + x^28 + 1 (0x900001), Period 2^31 - 1 (2147483647) bits - TODO |
| * |
| * |
| * @ref ITU-T Recommendation O.150, 05/96 |
| * @ref http://pl.wikipedia.org/wiki/PRBS |
| * @ref http://en.wikipedia.org/wiki/Pseudorandom_binary_sequence |
| * LFSR (Linear feedback shift register) |
| * @ref http://en.wikipedia.org/wiki/LFSR |
| * |
| * Author: Yongsen Chen, YongsenChen@gmail.com |
| */ |
| |
| |
| |
| #define PRBS_POLYNOMIAL_DEFAULT (0) |
| |
| |
| enum prbs_type { |
| PRBS7 = 7, |
| PRBS9 = 9, |
| PRBS11 = 11, |
| PRBS15 = 15, |
| PRBS17 = 17, |
| PRBS23 = 23, |
| PRBS31 = 31 |
| }; |
| |
| #define PRBS11_CYCLE_BITS ((1 << 11) - 1) |
| #define PRBS11_CYCLE_ALIGNED_BYTES ((PRBS11_CYCLE_BITS + 8 - 1)/8) |
| |
| #define PRBS15_CYCLE_BITS ((1 << 15) - 1) |
| #define PRBS15_CYCLE_ALIGNED_BYTES ((PRBS15_CYCLE_BITS + 8 - 1)/8) |
| |
| #define PRBS17_CYCLE_BITS ((1 << 17) - 1) |
| #define PRBS17_CYCLE_ALIGNED_BYTES ((PRBS17_CYCLE_BITS + 8 - 1)/8) |
| |
| #define PRBS23_CYCLE_BITS ((1 << 23) - 1) |
| #define PRBS23_CYCLE_ALIGNED_BYTES ((PRBS23_CYCLE_BITS + 8 - 1)/8) |
| |
| #define PRBS31_CYCLE_BITS ((1 << 31) - 1) |
| #define PRBS31_CYCLE_ALIGNED_BYTES ((PRBS31_CYCLE_BITS + 8 - 1)/8) |
| |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif /* __cplusplus */ |
| |
| /** Generate PRBS-15 data by polynomial and seed. |
| * |
| * @param polynomial PRBS polynomial, only support 0xC001 at present. |
| * @param seed Seed of the PRBS. |
| * @param buf Buffer to save the result. |
| * @param length Length in bytes to generate. |
| * @param reverse_output Whether to reverse the output bits. |
| * |
| * @return unsigned short Next seed or last data in LFSR buffer. |
| * |
| */ |
| unsigned short prbs15_gen(unsigned short polynomial, |
| unsigned short seed, |
| unsigned char *buf, |
| int length, |
| int reverse_output); |
| |
| #ifdef __cplusplus |
| } /* extern "C" */ |
| #endif /* __cplusplus */ |
| |
| #endif /* _PRBS_H_ */ |
