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diff --git a/Documentation/DocBook/librs.tmpl b/Documentation/DocBook/librs.tmpl deleted file mode 100644 index 94f21361e0ed..000000000000 --- a/Documentation/DocBook/librs.tmpl +++ /dev/null @@ -1,289 +0,0 @@ -<?xml version="1.0" encoding="UTF-8"?> -<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" - "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []> - -<book id="Reed-Solomon-Library-Guide"> - <bookinfo> - <title>Reed-Solomon Library Programming Interface</title> - - <authorgroup> - <author> - <firstname>Thomas</firstname> - <surname>Gleixner</surname> - <affiliation> - <address> - <email>tglx@linutronix.de</email> - </address> - </affiliation> - </author> - </authorgroup> - - <copyright> - <year>2004</year> - <holder>Thomas Gleixner</holder> - </copyright> - - <legalnotice> - <para> - This documentation 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. - </para> - - <para> - 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. - </para> - - <para> - 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., 59 Temple Place, Suite 330, Boston, - MA 02111-1307 USA - </para> - - <para> - For more details see the file COPYING in the source - distribution of Linux. - </para> - </legalnotice> - </bookinfo> - -<toc></toc> - - <chapter id="intro"> - <title>Introduction</title> - <para> - The generic Reed-Solomon Library provides encoding, decoding - and error correction functions. - </para> - <para> - Reed-Solomon codes are used in communication and storage - applications to ensure data integrity. - </para> - <para> - This documentation is provided for developers who want to utilize - the functions provided by the library. - </para> - </chapter> - - <chapter id="bugs"> - <title>Known Bugs And Assumptions</title> - <para> - None. - </para> - </chapter> - - <chapter id="usage"> - <title>Usage</title> - <para> - This chapter provides examples of how to use the library. - </para> - <sect1> - <title>Initializing</title> - <para> - The init function init_rs returns a pointer to an - rs decoder structure, which holds the necessary - information for encoding, decoding and error correction - with the given polynomial. It either uses an existing - matching decoder or creates a new one. On creation all - the lookup tables for fast en/decoding are created. - The function may take a while, so make sure not to - call it in critical code paths. - </para> - <programlisting> -/* the Reed Solomon control structure */ -static struct rs_control *rs_decoder; - -/* Symbolsize is 10 (bits) - * Primitive polynomial is x^10+x^3+1 - * first consecutive root is 0 - * primitive element to generate roots = 1 - * generator polynomial degree (number of roots) = 6 - */ -rs_decoder = init_rs (10, 0x409, 0, 1, 6); - </programlisting> - </sect1> - <sect1> - <title>Encoding</title> - <para> - The encoder calculates the Reed-Solomon code over - the given data length and stores the result in - the parity buffer. Note that the parity buffer must - be initialized before calling the encoder. - </para> - <para> - The expanded data can be inverted on the fly by - providing a non-zero inversion mask. The expanded data is - XOR'ed with the mask. This is used e.g. for FLASH - ECC, where the all 0xFF is inverted to an all 0x00. - The Reed-Solomon code for all 0x00 is all 0x00. The - code is inverted before storing to FLASH so it is 0xFF - too. This prevents that reading from an erased FLASH - results in ECC errors. - </para> - <para> - The databytes are expanded to the given symbol size - on the fly. There is no support for encoding continuous - bitstreams with a symbol size != 8 at the moment. If - it is necessary it should be not a big deal to implement - such functionality. - </para> - <programlisting> -/* Parity buffer. Size = number of roots */ -uint16_t par[6]; -/* Initialize the parity buffer */ -memset(par, 0, sizeof(par)); -/* Encode 512 byte in data8. Store parity in buffer par */ -encode_rs8 (rs_decoder, data8, 512, par, 0); - </programlisting> - </sect1> - <sect1> - <title>Decoding</title> - <para> - The decoder calculates the syndrome over - the given data length and the received parity symbols - and corrects errors in the data. - </para> - <para> - If a syndrome is available from a hardware decoder - then the syndrome calculation is skipped. - </para> - <para> - The correction of the data buffer can be suppressed - by providing a correction pattern buffer and an error - location buffer to the decoder. The decoder stores the - calculated error location and the correction bitmask - in the given buffers. This is useful for hardware - decoders which use a weird bit ordering scheme. - </para> - <para> - The databytes are expanded to the given symbol size - on the fly. There is no support for decoding continuous - bitstreams with a symbolsize != 8 at the moment. If - it is necessary it should be not a big deal to implement - such functionality. - </para> - - <sect2> - <title> - Decoding with syndrome calculation, direct data correction - </title> - <programlisting> -/* Parity buffer. Size = number of roots */ -uint16_t par[6]; -uint8_t data[512]; -int numerr; -/* Receive data */ -..... -/* Receive parity */ -..... -/* Decode 512 byte in data8.*/ -numerr = decode_rs8 (rs_decoder, data8, par, 512, NULL, 0, NULL, 0, NULL); - </programlisting> - </sect2> - - <sect2> - <title> - Decoding with syndrome given by hardware decoder, direct data correction - </title> - <programlisting> -/* Parity buffer. Size = number of roots */ -uint16_t par[6], syn[6]; -uint8_t data[512]; -int numerr; -/* Receive data */ -..... -/* Receive parity */ -..... -/* Get syndrome from hardware decoder */ -..... -/* Decode 512 byte in data8.*/ -numerr = decode_rs8 (rs_decoder, data8, par, 512, syn, 0, NULL, 0, NULL); - </programlisting> - </sect2> - - <sect2> - <title> - Decoding with syndrome given by hardware decoder, no direct data correction. - </title> - <para> - Note: It's not necessary to give data and received parity to the decoder. - </para> - <programlisting> -/* Parity buffer. Size = number of roots */ -uint16_t par[6], syn[6], corr[8]; -uint8_t data[512]; -int numerr, errpos[8]; -/* Receive data */ -..... -/* Receive parity */ -..... -/* Get syndrome from hardware decoder */ -..... -/* Decode 512 byte in data8.*/ -numerr = decode_rs8 (rs_decoder, NULL, NULL, 512, syn, 0, errpos, 0, corr); -for (i = 0; i < numerr; i++) { - do_error_correction_in_your_buffer(errpos[i], corr[i]); -} - </programlisting> - </sect2> - </sect1> - <sect1> - <title>Cleanup</title> - <para> - The function free_rs frees the allocated resources, - if the caller is the last user of the decoder. - </para> - <programlisting> -/* Release resources */ -free_rs(rs_decoder); - </programlisting> - </sect1> - - </chapter> - - <chapter id="structs"> - <title>Structures</title> - <para> - This chapter contains the autogenerated documentation of the structures which are - used in the Reed-Solomon Library and are relevant for a developer. - </para> -!Iinclude/linux/rslib.h - </chapter> - - <chapter id="pubfunctions"> - <title>Public Functions Provided</title> - <para> - This chapter contains the autogenerated documentation of the Reed-Solomon functions - which are exported. - </para> -!Elib/reed_solomon/reed_solomon.c - </chapter> - - <chapter id="credits"> - <title>Credits</title> - <para> - The library code for encoding and decoding was written by Phil Karn. - </para> - <programlisting> - Copyright 2002, Phil Karn, KA9Q - May be used under the terms of the GNU General Public License (GPL) - </programlisting> - <para> - The wrapper functions and interfaces are written by Thomas Gleixner. - </para> - <para> - Many users have provided bugfixes, improvements and helping hands for testing. - Thanks a lot. - </para> - <para> - The following people have contributed to this document: - </para> - <para> - Thomas Gleixner<email>tglx@linutronix.de</email> - </para> - </chapter> -</book> |