diff options
Diffstat (limited to 'drivers/mtd/nand/rtc_from4.c')
| -rw-r--r-- | drivers/mtd/nand/rtc_from4.c | 94 |
1 files changed, 89 insertions, 5 deletions
diff --git a/drivers/mtd/nand/rtc_from4.c b/drivers/mtd/nand/rtc_from4.c index a4d8d2e62e9e..031051cbde76 100644 --- a/drivers/mtd/nand/rtc_from4.c +++ b/drivers/mtd/nand/rtc_from4.c @@ -6,7 +6,7 @@ * Derived from drivers/mtd/nand/spia.c * Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com) * - * $Id: rtc_from4.c,v 1.8 2005/01/17 19:44:36 dmarlin Exp $ + * $Id: rtc_from4.c,v 1.9 2005/01/24 20:40:11 dmarlin Exp $ * * 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 @@ -83,9 +83,14 @@ static struct mtd_info *rtc_from4_mtd = NULL; #define RTC_FROM4_RS_ECC_CHK (RTC_FROM4_NAND_ADDR_FPGA | 0x00000070) #define RTC_FROM4_RS_ECC_CHK_ERROR (1 << 7) +#define ERR_STAT_ECC_AVAILABLE 0x20 + /* Undefine for software ECC */ #define RTC_FROM4_HWECC 1 +/* Define as 1 for no virtual erase blocks (in JFFS2) */ +#define RTC_FROM4_NO_VIRTBLOCKS 0 + /* * Module stuff */ @@ -267,7 +272,6 @@ static void rtc_from4_nand_select_chip(struct mtd_info *mtd, int chip) } - /* * rtc_from4_nand_device_ready - hardware specific ready/busy check * @mtd: MTD device structure @@ -363,6 +367,7 @@ static void rtc_from4_enable_hwecc(struct mtd_info *mtd, int mode) } + /* * rtc_from4_calculate_ecc - hardware specific code to read ECC code * @mtd: MTD device structure @@ -390,6 +395,7 @@ static void rtc_from4_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_c ecc_code[7] |= 0x0f; /* set the last four bits (not used) */ } + /* * rtc_from4_correct_data - hardware specific code to correct data using ECC code * @mtd: MTD device structure @@ -399,10 +405,8 @@ static void rtc_from4_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_c * * The FPGA tells us fast, if there's an error or not. If no, we go back happy * else we read the ecc results from the fpga and call the rs library to decode - * and hopefully correct the error + * and hopefully correct the error. * - * For now I use the code, which we read from the FLASH to use the RS lib, - * as the syndrom conversion has a unresolved issue. */ static int rtc_from4_correct_data(struct mtd_info *mtd, const u_char *buf, u_char *ecc1, u_char *ecc2) { @@ -457,8 +461,79 @@ static int rtc_from4_correct_data(struct mtd_info *mtd, const u_char *buf, u_cha } return res; } + + +/** + * rtc_from4_errstat - perform additional error status checks + * @mtd: MTD device structure + * @this: NAND chip structure + * @state: state or the operation + * @status: status code returned from read status + * @page: startpage inside the chip, must be called with (page & this->pagemask) + * + * Perform additional error status checks on erase and write failures + * to determine if errors are correctable. For this device, correctable + * 1-bit errors on erase and write are considered acceptable. + * + * note: see pages 34..37 of data sheet for details. + * + */ +static int rtc_from4_errstat(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page) +{ + int er_stat=0; + int rtn, retlen; + size_t len; + uint8_t *buf; + int i; + + this->cmdfunc (mtd, NAND_CMD_STATUS_CLEAR, -1, -1); + + if (state == FL_ERASING) { + for (i=0; i<4; i++) { + if (status & 1<<(i+1)) { + this->cmdfunc (mtd, (NAND_CMD_STATUS_ERROR + i + 1), -1, -1); + rtn = this->read_byte(mtd); + this->cmdfunc (mtd, NAND_CMD_STATUS_RESET, -1, -1); + if (!(rtn & ERR_STAT_ECC_AVAILABLE)) { + er_stat |= 1<<(i+1); /* err_ecc_not_avail */ + } + } + } + } else if (state == FL_WRITING) { + /* single bank write logic */ + this->cmdfunc (mtd, NAND_CMD_STATUS_ERROR, -1, -1); + rtn = this->read_byte(mtd); + this->cmdfunc (mtd, NAND_CMD_STATUS_RESET, -1, -1); + if (!(rtn & ERR_STAT_ECC_AVAILABLE)) { + er_stat |= 1<<1; /* err_ecc_not_avail */ + } else { + len = mtd->oobblock; + buf = kmalloc (len, GFP_KERNEL); + if (!buf) { + printk (KERN_ERR "rtc_from4_errstat: Out of memory!\n"); + er_stat = 1; /* if we can't check, assume failed */ + } else { + /* recovery read */ + /* page read */ + rtn = nand_do_read_ecc (mtd, page, len, &retlen, buf, NULL, this->autooob, 1); + if (rtn) { /* if read failed or > 1-bit error corrected */ + er_stat |= 1<<1; /* ECC read failed */ + } + kfree(buf); + } + } + } + + rtn = status; + if (er_stat == 0) { /* if ECC is available */ + rtn = (status & ~NAND_STATUS_FAIL); /* clear the error bit */ + } + + return rtn; +} #endif + /* * Main initialization routine */ @@ -518,6 +593,8 @@ int __init rtc_from4_init (void) this->eccmode = NAND_ECC_HW8_512; this->options |= NAND_HWECC_SYNDROME; + /* return the status of extra status and ECC checks */ + this->errstat = rtc_from4_errstat; /* set the nand_oobinfo to support FPGA H/W error detection */ this->autooob = &rtc_from4_nand_oobinfo; this->enable_hwecc = rtc_from4_enable_hwecc; @@ -544,6 +621,13 @@ int __init rtc_from4_init (void) deplete(rtc_from4_mtd, i); } +#if RTC_FROM4_NO_VIRTBLOCKS + /* use a smaller erase block to minimize wasted space when a block is bad */ + /* note: this uses eight times as much RAM as using the default and makes */ + /* mounts take four times as long. */ + rtc_from4_mtd->flags |= MTD_NO_VIRTBLOCKS; +#endif + /* Register the partitions */ add_mtd_partitions(rtc_from4_mtd, partition_info, NUM_PARTITIONS); |