* 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
#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[] = {
{
}
-
/*
* rtc_from4_nand_device_ready - hardware specific ready/busy check
* @mtd: MTD device structure
}
+
+/*
+ * 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
}
+
/*
* rtc_from4_calculate_ecc - hardware specific code to read ECC code
* @mtd: MTD device structure
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
*
* 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;
}
/* 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
*/
{
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),
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;
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);
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