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-rw-r--r--drivers/mtd/nand/nand_bch.c247
1 files changed, 0 insertions, 247 deletions
diff --git a/drivers/mtd/nand/nand_bch.c b/drivers/mtd/nand/nand_bch.c
deleted file mode 100644
index b94ecdf8d9..0000000000
--- a/drivers/mtd/nand/nand_bch.c
+++ /dev/null
@@ -1,247 +0,0 @@
-/*
- * This file provides ECC correction for more than 1 bit per block of data,
- * using binary BCH codes. It relies on the generic BCH library lib/bch.c.
- *
- * Copyright © 2011 Ivan Djelic <ivan.djelic@parrot.com>
- *
- * 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.
- *
- */
-
-#include <common.h>
-#include <malloc.h>
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/bitops.h>
-#include <linux/mtd/mtd.h>
-#include <linux/mtd/nand.h>
-#include <linux/mtd/nand_bch.h>
-#include <linux/bch.h>
-
-/**
- * struct nand_bch_control - private NAND BCH control structure
- * @bch: BCH control structure
- * @ecclayout: private ecc layout for this BCH configuration
- * @errloc: error location array
- * @eccmask: XOR ecc mask, allows erased pages to be decoded as valid
- */
-struct nand_bch_control {
- struct bch_control *bch;
- struct nand_ecclayout ecclayout;
- unsigned int *errloc;
- unsigned char *eccmask;
-};
-
-/**
- * nand_bch_calculate_ecc - [NAND Interface] Calculate ECC for data block
- * @mtd: MTD block structure
- * @buf: input buffer with raw data
- * @code: output buffer with ECC
- */
-int nand_bch_calculate_ecc(struct mtd_info *mtd, const unsigned char *buf,
- unsigned char *code)
-{
- const struct nand_chip *chip = mtd_to_nand(mtd);
- struct nand_bch_control *nbc = chip->ecc.priv;
- unsigned int i;
-
- memset(code, 0, chip->ecc.bytes);
- encode_bch(nbc->bch, buf, chip->ecc.size, code);
-
- /* apply mask so that an erased page is a valid codeword */
- for (i = 0; i < chip->ecc.bytes; i++)
- code[i] ^= nbc->eccmask[i];
-
- return 0;
-}
-EXPORT_SYMBOL(nand_bch_calculate_ecc);
-
-/**
- * nand_bch_correct_data - [NAND Interface] Detect and correct bit error(s)
- * @mtd: MTD block structure
- * @buf: raw data read from the chip
- * @read_ecc: ECC from the chip
- * @calc_ecc: the ECC calculated from raw data
- *
- * Detect and correct bit errors for a data byte block
- */
-int nand_bch_correct_data(struct mtd_info *mtd, unsigned char *buf,
- unsigned char *read_ecc, unsigned char *calc_ecc)
-{
- const struct nand_chip *chip = mtd_to_nand(mtd);
- struct nand_bch_control *nbc = chip->ecc.priv;
- unsigned int *errloc = nbc->errloc;
- int i, count;
-
- count = decode_bch(nbc->bch, NULL, chip->ecc.size, read_ecc, calc_ecc,
- NULL, errloc);
- if (count > 0) {
- for (i = 0; i < count; i++) {
- if (errloc[i] < (chip->ecc.size*8))
- /* error is located in data, correct it */
- buf[errloc[i] >> 3] ^= (1 << (errloc[i] & 7));
- /* else error in ecc, no action needed */
-
- pr_debug("%s: corrected bitflip %u\n", __func__,
- errloc[i]);
- }
- } else if (count < 0) {
- printk(KERN_ERR "ecc unrecoverable error\n");
- count = -1;
- }
- return count;
-}
-EXPORT_SYMBOL(nand_bch_correct_data);
-
-/**
- * nand_bch_init - [NAND Interface] Initialize NAND BCH error correction
- * @mtd: MTD block structure
- *
- * Returns:
- * a pointer to a new NAND BCH control structure, or NULL upon failure
- *
- * Initialize NAND BCH error correction. Parameters @eccsize and @eccbytes
- * are used to compute BCH parameters m (Galois field order) and t (error
- * correction capability). @eccbytes should be equal to the number of bytes
- * required to store m*t bits, where m is such that 2^m-1 > @eccsize*8.
- *
- * Example: to configure 4 bit correction per 512 bytes, you should pass
- * @eccsize = 512 (thus, m=13 is the smallest integer such that 2^m-1 > 512*8)
- * @eccbytes = 7 (7 bytes are required to store m*t = 13*4 = 52 bits)
- */
-struct nand_bch_control *nand_bch_init(struct mtd_info *mtd)
-{
- struct nand_chip *nand = mtd_to_nand(mtd);
- unsigned int m, t, eccsteps, i;
- struct nand_ecclayout *layout = nand->ecc.layout;
- struct nand_bch_control *nbc = NULL;
- unsigned char *erased_page;
- unsigned int eccsize = nand->ecc.size;
- unsigned int eccbytes = nand->ecc.bytes;
- unsigned int eccstrength = nand->ecc.strength;
-
- if (!eccbytes && eccstrength) {
- eccbytes = DIV_ROUND_UP(eccstrength * fls(8 * eccsize), 8);
- nand->ecc.bytes = eccbytes;
- }
-
- if (!eccsize || !eccbytes) {
- printk(KERN_WARNING "ecc parameters not supplied\n");
- goto fail;
- }
-
- m = fls(1+8*eccsize);
- t = (eccbytes*8)/m;
-
- nbc = kzalloc(sizeof(*nbc), GFP_KERNEL);
- if (!nbc)
- goto fail;
-
- nbc->bch = init_bch(m, t, 0);
- if (!nbc->bch)
- goto fail;
-
- /* verify that eccbytes has the expected value */
- if (nbc->bch->ecc_bytes != eccbytes) {
- printk(KERN_WARNING "invalid eccbytes %u, should be %u\n",
- eccbytes, nbc->bch->ecc_bytes);
- goto fail;
- }
-
- eccsteps = mtd->writesize/eccsize;
-
- /* if no ecc placement scheme was provided, build one */
- if (!layout) {
-
- /* handle large page devices only */
- if (mtd->oobsize < 64) {
- printk(KERN_WARNING "must provide an oob scheme for "
- "oobsize %d\n", mtd->oobsize);
- goto fail;
- }
-
- layout = &nbc->ecclayout;
- layout->eccbytes = eccsteps*eccbytes;
-
- /* reserve 2 bytes for bad block marker */
- if (layout->eccbytes+2 > mtd->oobsize) {
- printk(KERN_WARNING "no suitable oob scheme available "
- "for oobsize %d eccbytes %u\n", mtd->oobsize,
- eccbytes);
- goto fail;
- }
- /* put ecc bytes at oob tail */
- for (i = 0; i < layout->eccbytes; i++)
- layout->eccpos[i] = mtd->oobsize-layout->eccbytes+i;
-
- layout->oobfree[0].offset = 2;
- layout->oobfree[0].length = mtd->oobsize-2-layout->eccbytes;
-
- nand->ecc.layout = layout;
- }
-
- /* sanity checks */
- if (8*(eccsize+eccbytes) >= (1 << m)) {
- printk(KERN_WARNING "eccsize %u is too large\n", eccsize);
- goto fail;
- }
- if (layout->eccbytes != (eccsteps*eccbytes)) {
- printk(KERN_WARNING "invalid ecc layout\n");
- goto fail;
- }
-
- nbc->eccmask = kmalloc(eccbytes, GFP_KERNEL);
- nbc->errloc = kmalloc(t*sizeof(*nbc->errloc), GFP_KERNEL);
- if (!nbc->eccmask || !nbc->errloc)
- goto fail;
- /*
- * compute and store the inverted ecc of an erased ecc block
- */
- erased_page = kmalloc(eccsize, GFP_KERNEL);
- if (!erased_page)
- goto fail;
-
- memset(erased_page, 0xff, eccsize);
- memset(nbc->eccmask, 0, eccbytes);
- encode_bch(nbc->bch, erased_page, eccsize, nbc->eccmask);
- kfree(erased_page);
-
- for (i = 0; i < eccbytes; i++)
- nbc->eccmask[i] ^= 0xff;
-
- if (!eccstrength)
- nand->ecc.strength = (eccbytes * 8) / fls(8 * eccsize);
-
- return nbc;
-fail:
- nand_bch_free(nbc);
- return NULL;
-}
-EXPORT_SYMBOL(nand_bch_init);
-
-/**
- * nand_bch_free - [NAND Interface] Release NAND BCH ECC resources
- * @nbc: NAND BCH control structure
- */
-void nand_bch_free(struct nand_bch_control *nbc)
-{
- if (nbc) {
- free_bch(nbc->bch);
- kfree(nbc->errloc);
- kfree(nbc->eccmask);
- kfree(nbc);
- }
-}
-EXPORT_SYMBOL(nand_bch_free);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Ivan Djelic <ivan.djelic@parrot.com>");
-MODULE_DESCRIPTION("NAND software BCH ECC support");
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-14 08:31:28 +0000