| /* |

| * Generic binary BCH encoding/decoding library |

| * |

| * This program is free software; you can redistribute it and/or modify it |

| * under the terms of the GNU General Public License version 2 as published by |

| * the Free Software Foundation. |

| * |

| * This program is distributed in the hope that it will be useful, but WITHOUT |

| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |

| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |

| * more details. |

| * |

| * You should have received a copy of the GNU General Public License along with |

| * this program; if not, write to the Free Software Foundation, Inc., 51 |

| * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |

| * |

| * Copyright © 2011 Parrot S.A. |

| * |

| * Author: Ivan Djelic <ivan.djelic@parrot.com> |

| * |

| * Description: |

| * |

| * This library provides runtime configurable encoding/decoding of binary |

| * Bose-Chaudhuri-Hocquenghem (BCH) codes. |

| */ |

| #ifndef _BCH_H |

| #define _BCH_H |

| |

| #include <linux/types.h> |

| |

| /** |

| * struct bch_control - BCH control structure |

| * @m: Galois field order |

| * @n: maximum codeword size in bits (= 2^m-1) |

| * @t: error correction capability in bits |

| * @ecc_bits: ecc exact size in bits, i.e. generator polynomial degree (<=m*t) |

| * @ecc_bytes: ecc max size (m*t bits) in bytes |

| * @a_pow_tab: Galois field GF(2^m) exponentiation lookup table |

| * @a_log_tab: Galois field GF(2^m) log lookup table |

| * @mod8_tab: remainder generator polynomial lookup tables |

| * @ecc_buf: ecc parity words buffer |

| * @ecc_buf2: ecc parity words buffer |

| * @xi_tab: GF(2^m) base for solving degree 2 polynomial roots |

| * @syn: syndrome buffer |

| * @cache: log-based polynomial representation buffer |

| * @elp: error locator polynomial |

| * @poly_2t: temporary polynomials of degree 2t |

| */ |

| struct bch_control { |

| unsigned int m; |

| unsigned int n; |

| unsigned int t; |

| unsigned int ecc_bits; |

| unsigned int ecc_bytes; |

| /* private: */ |

| uint16_t *a_pow_tab; |

| uint16_t *a_log_tab; |

| uint32_t *mod8_tab; |

| uint32_t *ecc_buf; |

| uint32_t *ecc_buf2; |

| unsigned int *xi_tab; |

| unsigned int *syn; |

| int *cache; |

| struct gf_poly *elp; |

| struct gf_poly *poly_2t[4]; |

| }; |

| |

| struct bch_control *init_bch(int m, int t, unsigned int prim_poly); |

| |

| void free_bch(struct bch_control *bch); |

| |

| void encode_bch(struct bch_control *bch, const uint8_t *data, |

| unsigned int len, uint8_t *ecc); |

| |

| int decode_bch(struct bch_control *bch, const uint8_t *data, unsigned int len, |

| const uint8_t *recv_ecc, const uint8_t *calc_ecc, |

| const unsigned int *syn, unsigned int *errloc); |

| |

| #endif /* _BCH_H */ |