diff options
Diffstat (limited to 'drivers/mtd/nand/rtc_from4.c')
-rw-r--r-- | drivers/mtd/nand/rtc_from4.c | 140 |
1 files changed, 132 insertions, 8 deletions
diff --git a/drivers/mtd/nand/rtc_from4.c b/drivers/mtd/nand/rtc_from4.c index 02305a2adca..031051cbde7 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 1.7 2004/11/04 12:53:10 gleixner 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 @@ -83,13 +83,18 @@ 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 */ -static void __iomem *rtc_from4_fio_base = P2SEGADDR(RTC_FROM4_FIO_BASE); +static void __iomem *rtc_from4_fio_base = (void *)P2SEGADDR(RTC_FROM4_FIO_BASE); const static struct mtd_partition partition_info[] = { { @@ -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 @@ -286,6 +290,40 @@ static int rtc_from4_nand_device_ready(struct mtd_info *mtd) } + +/* + * deplete - code to perform device recovery in case there was a power loss + * @mtd: MTD device structure + * @chip: Chip to select (0 == slot 3, 1 == slot 4) + * + * If there was a sudden loss of power during an erase operation, a + * "device recovery" operation must be performed when power is restored + * to ensure correct operation. This routine performs the required steps + * for the requested chip. + * + * See page 86 of the data sheet for details. + * + */ +static void deplete(struct mtd_info *mtd, int chip) +{ + struct nand_chip *this = mtd->priv; + + /* wait until device is ready */ + while (!this->dev_ready(mtd)); + + this->select_chip(mtd, chip); + + /* Send the commands for device recovery, phase 1 */ + this->cmdfunc (mtd, NAND_CMD_DEPLETE1, 0x0000, 0x0000); + this->cmdfunc (mtd, NAND_CMD_DEPLETE2, -1, -1); + + /* Send the commands for device recovery, phase 2 */ + this->cmdfunc (mtd, NAND_CMD_DEPLETE1, 0x0000, 0x0004); + this->cmdfunc (mtd, NAND_CMD_DEPLETE2, -1, -1); + +} + + #ifdef RTC_FROM4_HWECC /* * rtc_from4_enable_hwecc - hardware specific hardware ECC enable function @@ -329,6 +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 @@ -356,6 +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 @@ -365,16 +405,14 @@ 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) { int i, j, res; unsigned short status; - uint16_t par[6], syn[6], tmp; + uint16_t par[6], syn[6]; uint8_t ecc[8]; volatile unsigned short *rs_ecc; @@ -416,15 +454,86 @@ static int rtc_from4_correct_data(struct mtd_info *mtd, const u_char *buf, u_cha } /* Let the library code do its magic.*/ - res = decode_rs8(rs_decoder, buf, par, 512, syn, 0, NULL, 0xff, NULL); + res = decode_rs8(rs_decoder, (uint8_t *)buf, par, 512, syn, 0, NULL, 0xff, NULL); if (res > 0) { DEBUG (MTD_DEBUG_LEVEL0, "rtc_from4_correct_data: " "ECC corrected %d errors on read\n", res); } 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 */ @@ -432,6 +541,7 @@ int __init rtc_from4_init (void) { struct nand_chip *this; unsigned short bcr1, bcr2, wcr2; + int i; /* Allocate memory for MTD device structure and private data */ rtc_from4_mtd = kmalloc(sizeof(struct mtd_info) + sizeof (struct nand_chip), @@ -483,6 +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; @@ -504,6 +616,18 @@ int __init rtc_from4_init (void) return -ENXIO; } + /* Perform 'device recovery' for each chip in case there was a power loss. */ + for (i=0; i < this->numchips; i++) { + 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); |