From cbfa0304f96c7e3d30f83d9feb7b7f23a197e4b1 Mon Sep 17 00:00:00 2001 From: oharboe Date: Tue, 12 May 2009 17:29:16 +0000 Subject: [PATCH] 4-bit ECC support for Marvell Kirkwood SOC git-svn-id: svn://svn.berlios.de/openocd/trunk@1768 b42882b7-edfa-0310-969c-e2dbd0fdcd60 --- src/flash/Makefile.am | 2 +- src/flash/nand.c | 19 +++- src/flash/nand.h | 2 + src/flash/nand_ecc_kw.c | 174 ++++++++++++++++++++++++++++++++ src/target/board/sheevaplug.cfg | 4 +- 5 files changed, 197 insertions(+), 4 deletions(-) create mode 100644 src/flash/nand_ecc_kw.c diff --git a/src/flash/Makefile.am b/src/flash/Makefile.am index 7895edc85a..e5b76cb61b 100644 --- a/src/flash/Makefile.am +++ b/src/flash/Makefile.am @@ -7,7 +7,7 @@ METASOURCES = AUTO noinst_LTLIBRARIES = libflash.la libflash_la_SOURCES = \ flash.c lpc2000.c cfi.c non_cfi.c at91sam7.c \ - str7x.c str9x.c aduc702x.c nand.c nand_ecc.c \ + str7x.c str9x.c aduc702x.c nand.c nand_ecc.c nand_ecc_kw.c \ lpc3180_nand_controller.c stellaris.c str9xpec.c stm32x.c tms470.c \ ecos.c orion_nand.c s3c24xx_nand.c s3c2410_nand.c s3c2412_nand.c \ s3c2440_nand.c s3c2443_nand.c lpc288x.c ocl.c mflash.c pic32mx.c avrf.c diff --git a/src/flash/nand.c b/src/flash/nand.c index 8efed037c6..057feb7d94 100644 --- a/src/flash/nand.c +++ b/src/flash/nand.c @@ -1332,6 +1332,8 @@ static int handle_nand_write_command(struct command_context_s *cmd_ctx, char *cm oob_format |= NAND_OOB_RAW | NAND_OOB_ONLY; else if (!strcmp(args[i], "oob_softecc")) oob_format |= NAND_OOB_SW_ECC; + else if (!strcmp(args[i], "oob_softecc_kw")) + oob_format |= NAND_OOB_SW_ECC_KW; else { command_print(cmd_ctx, "unknown option: %s", args[i]); @@ -1355,7 +1357,7 @@ static int handle_nand_write_command(struct command_context_s *cmd_ctx, char *cm page = malloc(p->page_size); } - if (oob_format & (NAND_OOB_RAW | NAND_OOB_SW_ECC)) + if (oob_format & (NAND_OOB_RAW | NAND_OOB_SW_ECC | NAND_OOB_SW_ECC_KW)) { if (p->page_size == 512) { oob_size = 16; @@ -1401,6 +1403,21 @@ static int handle_nand_write_command(struct command_context_s *cmd_ctx, char *cm oob[eccpos[j++]] = ecc[1]; oob[eccpos[j++]] = ecc[2]; } + } else if (oob_format & NAND_OOB_SW_ECC_KW) + { + /* + * In this case eccpos is not used as + * the ECC data is always stored contigously + * at the end of the OOB area. It consists + * of 10 bytes per 512-byte data block. + */ + u32 i; + u8 *ecc = oob + oob_size - page_size/512 * 10; + memset(oob, 0xff, oob_size); + for (i = 0; i < page_size; i += 512) { + nand_calculate_ecc_kw(p, page+i, ecc); + ecc += 10; + } } else if (NULL != oob) { diff --git a/src/flash/nand.h b/src/flash/nand.h index bd9554c344..b3c6b6b566 100644 --- a/src/flash/nand.h +++ b/src/flash/nand.h @@ -200,6 +200,7 @@ enum oob_formats NAND_OOB_ONLY = 0x2, /* only OOB data */ NAND_OOB_SW_ECC = 0x10, /* when writing, use SW ECC (as opposed to no ECC) */ NAND_OOB_HW_ECC = 0x20, /* when writing, use HW ECC (as opposed to no ECC) */ + NAND_OOB_SW_ECC_KW = 0x40, /* when writing, use Marvell's Kirkwood bootrom format */ NAND_OOB_JFFS2 = 0x100, /* when writing, use JFFS2 OOB layout */ NAND_OOB_YAFFS2 = 0x100,/* when writing, use YAFFS2 OOB layout */ }; @@ -210,6 +211,7 @@ extern int nand_read_page_raw(struct nand_device_s *device, u32 page, u8 *data, extern int nand_write_page_raw(struct nand_device_s *device, u32 page, u8 *data, u32 data_size, u8 *oob, u32 oob_size); extern int nand_read_status(struct nand_device_s *device, u8 *status); extern int nand_calculate_ecc(struct nand_device_s *device, const u8 *dat, u8 *ecc_code); +extern int nand_calculate_ecc_kw(struct nand_device_s *device, const u8 *dat, u8 *ecc_code); extern int nand_register_commands(struct command_context_s *cmd_ctx); extern int nand_init(struct command_context_s *cmd_ctx); diff --git a/src/flash/nand_ecc_kw.c b/src/flash/nand_ecc_kw.c new file mode 100644 index 0000000000..ecc7adc265 --- /dev/null +++ b/src/flash/nand_ecc_kw.c @@ -0,0 +1,174 @@ +/* + * Reed-Solomon ECC handling for the Marvell Kirkwood SOC + * Copyright (C) 2009 Marvell Semiconductor, Inc. + * + * Authors: Lennert Buytenhek + * Nicolas Pitre + * + * This file is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 or (at your option) any + * later version. + * + * This file 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. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include +#include "nand.h" + + +/***************************************************************************** + * Arithmetic in GF(2^10) ("F") modulo x^10 + x^3 + 1. + * + * For multiplication, a discrete log/exponent table is used, with + * primitive element x (F is a primitive field, so x is primitive). + */ +#define MODPOLY 0x409 /* x^10 + x^3 + 1 in binary */ + +/* + * Maps an integer a [0..1022] to a polynomial b = gf_exp[a] in + * GF(2^10) mod x^10 + x^3 + 1 such that b = x ^ a. There's two + * identical copies of this array back-to-back so that we can save + * the mod 1023 operation when doing a GF multiplication. + */ +static uint16_t gf_exp[1023 + 1023]; + +/* + * Maps a polynomial b in GF(2^10) mod x^10 + x^3 + 1 to an index + * a = gf_log[b] in [0..1022] such that b = x ^ a. + */ +static uint16_t gf_log[1024]; + +static void gf_build_log_exp_table(void) +{ + int i; + int p_i; + + /* + * p_i = x ^ i + * + * Initialise to 1 for i = 0. + */ + p_i = 1; + + for (i = 0; i < 1023; i++) { + gf_exp[i] = p_i; + gf_exp[i + 1023] = p_i; + gf_log[p_i] = i; + + /* + * p_i = p_i * x + */ + p_i <<= 1; + if (p_i & (1 << 10)) + p_i ^= MODPOLY; + } +} + + +/***************************************************************************** + * Reed-Solomon code + * + * This implements a (1023,1015) Reed-Solomon ECC code over GF(2^10) + * mod x^10 + x^3 + 1, shortened to (520,512). The ECC data consists + * of 8 10-bit symbols, or 10 8-bit bytes. + * + * Given 512 bytes of data, computes 10 bytes of ECC. + * + * This is done by converting the 512 bytes to 512 10-bit symbols + * (elements of F), interpreting those symbols as a polynomial in F[X] + * by taking symbol 0 as the coefficient of X^8 and symbol 511 as the + * coefficient of X^519, and calculating the residue of that polynomial + * divided by the generator polynomial, which gives us the 8 ECC symbols + * as the remainder. Finally, we convert the 8 10-bit ECC symbols to 10 + * 8-bit bytes. + * + * The generator polynomial is hardcoded, as that is faster, but it + * can be computed by taking the primitive element a = x (in F), and + * constructing a polynomial in F[X] with roots a, a^2, a^3, ..., a^8 + * by multiplying the minimal polynomials for those roots (which are + * just 'x - a^i' for each i). + * + * Note: due to unfortunate circumstances, the bootrom in the Kirkwood SOC + * expects the ECC to be computed backward, i.e. from the last byte down + * to the first one. + */ +int nand_calculate_ecc_kw(struct nand_device_s *device, const u8 *data, u8 *ecc) +{ + unsigned int r7, r6, r5, r4, r3, r2, r1, r0; + int i; + static int tables_initialized = 0; + + if (!tables_initialized) { + gf_build_log_exp_table(); + tables_initialized = 1; + } + + /* + * Load bytes 504..511 of the data into r. + */ + r0 = data[504]; + r1 = data[505]; + r2 = data[506]; + r3 = data[507]; + r4 = data[508]; + r5 = data[509]; + r6 = data[510]; + r7 = data[511]; + + + /* + * Shift bytes 503..0 (in that order) into r0, followed + * by eight zero bytes, while reducing the polynomial by the + * generator polynomial in every step. + */ + for (i = 503; i >= -8; i--) { + unsigned int d; + + d = 0; + if (i >= 0) + d = data[i]; + + if (r7) { + u16 *t = gf_exp + gf_log[r7]; + + r7 = r6 ^ t[0x21c]; + r6 = r5 ^ t[0x181]; + r5 = r4 ^ t[0x18e]; + r4 = r3 ^ t[0x25f]; + r3 = r2 ^ t[0x197]; + r2 = r1 ^ t[0x193]; + r1 = r0 ^ t[0x237]; + r0 = d ^ t[0x024]; + } else { + r7 = r6; + r6 = r5; + r5 = r4; + r4 = r3; + r3 = r2; + r2 = r1; + r1 = r0; + r0 = d; + } + } + + ecc[0] = r0; + ecc[1] = (r0 >> 8) | (r1 << 2); + ecc[2] = (r1 >> 6) | (r2 << 4); + ecc[3] = (r2 >> 4) | (r3 << 6); + ecc[4] = (r3 >> 2); + ecc[5] = r4; + ecc[6] = (r4 >> 8) | (r5 << 2); + ecc[7] = (r5 >> 6) | (r6 << 4); + ecc[8] = (r6 >> 4) | (r7 << 6); + ecc[9] = (r7 >> 2); + + return 0; +} diff --git a/src/target/board/sheevaplug.cfg b/src/target/board/sheevaplug.cfg index 64e2596786..276d6f2462 100644 --- a/src/target/board/sheevaplug.cfg +++ b/src/target/board/sheevaplug.cfg @@ -99,7 +99,7 @@ proc sheevaplug_reflash_uboot { } { sheevaplug_init nand probe 0 nand erase 0 0 4 - nand write 0 uboot.bin 0 oob_softecc + nand write 0 uboot.bin 0 oob_softecc_kw resume } @@ -108,7 +108,7 @@ proc sheevaplug_load_uboot { } { # load u-Boot into RAM and execute it sheevaplug_init - load_image /tmp/uboot.elf + load_image uboot.elf verify_image uboot.elf resume 0x00600000 -- 2.30.2