?? smc_core.c
字號:
/* * vivi/drivers/mtd/nand/smc_core.c: * * Based on linux/drivers/mtd/nand/smc.c * * $Id: smc_core.c,v 1.3 2002/08/10 07:47:08 nandy Exp $ * * * 棱淬: * 恐 this->oobblock撈扼絆 沁闌鱉? thsi->oobblcok_ofs撈扼絆 竅擱 * 粱歹 疙犬竅瘤 臼闌鱉? */#include "config.h"#include "mtd/mtd.h"#include "mtd/nand.h"#include "mtd/nand_ids.h"#include "mtd/nand_ecc.h"#include "time.h"#include "printk.h"#include <types.h>#include <errno.h>/* * Macros for low-level register control */#define nand_select() this->hwcontrol(NAND_CTL_SETNCE); \ nand_command(mtd, NAND_CMD_RESET, -1, -1); \ udelay(10);#define nand_deselect() this->hwcontrol(NAND_CTL_CLRNCE);static inline void sm_swap(u_char *x, u_char *y) { u_char tmp; tmp = *x; *x = *y; *y = tmp;}/* define if you'll be using < 2M SMC device */#undef USE_256BYTE_NAND_FLASH/* * Send command to NAND device */static voidnand_command(struct mtd_info *mtd, unsigned command, int column, int page_addr){ register struct nand_chip *this = mtd->priv; /* Begin command latch cycle */ this->hwcontrol(NAND_CTL_SETCLE); this->hwcontrol(NAND_CTL_DAT_OUT); /* * Write out the command to the device. */ if (command != NAND_CMD_SEQIN) this->write_cmd(command); else { if (mtd->oobblock == 256 && column >= 256) { column -= 256; this->write_cmd(NAND_CMD_RESET); this->write_cmd(NAND_CMD_READOOB); this->write_cmd(NAND_CMD_SEQIN); } else if (mtd->oobblock == 512 && column >= 256) { if (column < 512) { column -= 256; this->write_cmd(NAND_CMD_READ1); this->write_cmd(NAND_CMD_SEQIN); } else { column -= 512; this->write_cmd(NAND_CMD_READOOB); this->write_cmd(NAND_CMD_SEQIN); } } else { this->write_cmd(NAND_CMD_READ0); this->write_cmd(NAND_CMD_SEQIN); } } /* Set ALE and clear CLE to start address cycle */ this->hwcontrol(NAND_CTL_CLRCLE); this->hwcontrol(NAND_CTL_SETALE); /* Serially input address */ if (column != -1) this->write_addr(column); if (page_addr != -1) { this->write_addr((u_char)(page_addr & 0xff)); this->write_addr((u_char)((page_addr >> 8) & 0xff)); /* One more address cycle for higher density devices */ if (mtd->size & 0x0c000000) { this->write_addr((u_char)((page_addr >> 16) & 0xff)); } } /* Latch in address */ this->hwcontrol(NAND_CTL_CLRALE); this->hwcontrol(NAND_CTL_DAT_IN); /* Pause for 15us */ udelay(15); }/* * NAND read */static intnand_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf){ int j, col, page, state; struct nand_chip *this = mtd->priv; DEBUG(MTD_DEBUG_LEVEL3, __FUNCTION__"(): from = 0x%08lx, len = %i\n", (unsigned int)from, (int)len); /* Do not allow reads past end of device */ if ((from + len) > mtd->size) { DEBUG(MTD_DEBUG_LEVEL0, __FUNCTION__"(): Attempt read beyond end of device\n"); *retlen = 0; return -EINVAL; } /* First we calculate the starting page */ page = from >> this->page_shift; /* Get raw starting column */ col = from & (mtd->oobblock - 1); /* State machine for devices having pages larger than 256 bytes */ state = (col < mtd->eccsize) ? 0 : 1; /* Calculate column address within ECC block context */ col = (col >= mtd->eccsize) ? (col - mtd->eccsize) : col; /* Initialize return value */ *retlen = 0; /* Select the NAND device */ nand_select(); /* Loop until all data read */ while (*retlen < len) { /* Send the read command */ if (!state) nand_command(mtd, NAND_CMD_READ0, col, page); else nand_command(mtd, NAND_CMD_READ1, col, page); this->wait_for_ready(); /* Read the data directly into the return buffer */ if ((*retlen + (mtd->eccsize - col)) >= len) { while (*retlen < len) buf[(*retlen)++] = this->read_data(); /* We're done */ continue; } else { for (j = col; j < mtd->eccsize; j++) buf[(*retlen)++] = this->read_data(); } /* * If the amount of data to be read is greater than * (256 - col), then all subsequent reads will take * place on page or half-page (in the case of 512 byte * page devices) aligned boundaries and the column * address will be zero. Setting the column address to * zero after the first read allows us to simplify * the reading of data and the if/else statements above. */ if (col) col = 0x00; /* Increment page address */ if ((mtd->oobblock == 256) || state) page++; /* Toggle state machine */ if (mtd->oobblock == 512) state = state ? 0 : 1; } /* De-select the NAND device */ nand_deselect(); /* Return happy */ return 0; }/* * if mtd->oobblock == 512 */inline intsmc_read_ecc_512(struct mtd_info *mtd, u_char *ecc_code){ struct nand_chip *this = mtd->priv; u_char ecc_calc[3]; int j, ret; /* Read in a block big enough for ECC */ for (j = 0; j < (mtd->oobblock + mtd->oobsize); j++) this->data_buf[j] = this->read_data(); for (j = 0; j < mtd->oobsize; j++) ecc_code[j] = this->data_buf[(mtd->oobblock + j)]; nand_calculate_ecc(&this->data_buf[0], &ecc_calc[0]); sm_swap(&ecc_calc[0], &ecc_calc[1]); DEBUG(MTD_DEBUG_LEVEL3, __FUNCTION__"(): ECC [%02x%02x%02x : %02x%02x%02x]\n", ecc_code[SMC_OOB_ECC1], ecc_code[SMC_OOB_ECC1+1], ecc_code[SMC_OOB_ECC1+2], ecc_calc[0], ecc_calc[1], ecc_calc[2]); ret = nand_correct_data(&this->data_buf[0], &(ecc_code[SMC_OOB_ECC1]), &ecc_calc[0]); if (ret == -1) return ret; nand_calculate_ecc(&this->data_buf[mtd->eccsize], &ecc_calc[0]); sm_swap(&ecc_calc[0], &ecc_calc[1]); DEBUG(MTD_DEBUG_LEVEL3, __FUNCTION__"(): ECC [%02x%02x%02x : %02x%02x%02x]\n", ecc_code[SMC_OOB_ECC2], ecc_code[SMC_OOB_ECC2+1], ecc_code[SMC_OOB_ECC2+2], ecc_calc[0], ecc_calc[1], ecc_calc[2]); ret = nand_correct_data(&this->data_buf[mtd->eccsize], &(ecc_code[SMC_OOB_ECC2]), &ecc_calc[0]); if (ret == -1) return ret; return 0;}/* * NAND read with ECC */static intnand_read_ecc(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf, u_char *ecc_code){ int j, offset, page; struct nand_chip *this = mtd->priv; int ret; DEBUG(MTD_DEBUG_LEVEL3, __FUNCTION__ "(): from = 0x%08x, len = %i\n", (unsigned int)from, (int)len); /* Do not allow reads past end of device */ if ((from + len) > mtd->size) { DEBUG(MTD_DEBUG_LEVEL0, __FUNCTION__ "(): Attempt read beyond end of device\n"); *retlen = 0; return -EINVAL; } /* Select the NAND device */ nand_select(); /* Initialize return value */ *retlen = 0;#ifdef USE_256BYTE_NAND_FLASH /* First we calculate the starting page */ page = from >> this->page_shift; /* Get raw starting column */ offset = from & (mtd->oobblock - 1); /* if the length of Page is 256bytes, * 2 Pages must be taken for 1 Sector and as a result, * higher level 8 bytes of information * among the above 16 byte information must coincide with * Spare(or OOB) of Even-Page while lowel level 8 bytes * coincide with Spar(or OOB) of Odd-page. * i.e, [0 block][oob][1 block][oob] * [2 block][oob][3 block][oob]... */ if (mtd->oobblock == 256) { u_char ecc_calc[3]; int oob_offset; /* Loop until all data read */ while (*retlen < len) { nand_command(mtd, NAND_CMD_READ0, 0x00, page); this->wait_for_ready(); /* Read in a block big enough for ECC */ for (j = 0; j < mtd->eccsize; j++) this->data_buf[j] = this->read_data(); if (!(page & 0x1)) { /* page is odd! */ nand_command(mtd, NAND_CMD_READOOB, SMC_OOB256_ECC1, page + 1); oob_offset = SMC_OOB_ECC1; } else { nand_command(mtd, NAND_CMD_READOOB, SMC_OOB256_ECC2, page); oob_offset = SMC_OOB_ECC2; } this->wait_for_ready(); for (j = 0; j < 3; j++) ecc_code[oob_offset + j] = this->read_data(); nand_calculate_ecc(&this->data_buf[0], &ecc_calc[0]); sm_swap(&ecc_calc[0], &ecc_calc[1]); ret = nand_correct_data(&this->data_buf[0], &(ecc_code[oob_offset]), &ecc_calc[0]); if (ret == -1) goto nand_read_ecc_err; /* Read the data from ECC data buffer into return buffer */ if ((*retlen + (mtd->eccsize - offset)) > = len) { while (*retlen < len) buf[(*retlen)++] = this->data_buf[offset++]; /* We're done */ continue; } else { for (j = offset; j < mtd->eccsize; j++) buf[(*retlen)++] = this->data_buf[j]; } /* * If the amount of data to be read is greater than * (256 - offset), then all subsequent reads will take * place on page or half-page (in the case of 512 byte * page devices) aligned boundaries and the column * address will be zero. Setting the column address to * to zero after the first read allows us to simplify * the reading of data and the if/else statements above. */ if (offset) offset = 0x00; /* Increment page address */ page++; } } else #endif /* USE_256BYTE_NAND_FLASH */ { /* mtd->oobblock == 512 */ size_t last, next, len2; last = from + len; for (next = from; from < last; ) { page = from >> this->page_shift; offset = from & (mtd->oobblock - 1); len2 = mtd->oobblock - offset; next += len2; nand_command(mtd, NAND_CMD_READ0, 0x00, page); this->wait_for_ready(); ret = smc_read_ecc_512(mtd, ecc_code); if (ret == -1) goto nand_read_ecc_err; if (next >= last) if ((last & (mtd->oobblock - 1)) != 0) len2 = (last & (mtd->oobblock - 1)) - offset; for (j = 0; j < len2; j++) buf[(*retlen) + j] = this->data_buf[offset + j]; *retlen += len2; from = next; } } ret = 0; /* De-select the NAND device */ nand_deselect(); return ret;nand_read_ecc_err: DEBUG(MTD_DEBUG_LEVEL0, __FUNCTION__"(): Failed ECC read, page 0x%08lx\n", page); return -EIO;}/* * NAND read out-of-band */static intnand_read_oob(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf){ int i, offset, page; struct nand_chip *this = mtd->priv; DEBUG(MTD_DEBUG_LEVEL3, __FUNCTION__ "(): from = 0x%08x, len = %i\n", (unsigned int)from, (int)len); /* Shift to get page */ page = ((int)from) >> this->page_shift; /* Mask to get column */ offset = from & 0x0f; /* Initialize return length value */ *retlen = 0; /* Do not allow read past end of page */ if ((offset + len) > mtd->oobsize) { DEBUG(MTD_DEBUG_LEVEL0, __FUNCTION__"(): Attempt read past end of page " \ "0x%08lx, column %i, length %i\n", page, offset, len); return -EINVAL; } /* Select the NAND device */ nand_select(); /* Send the read command */ nand_command(mtd, NAND_CMD_READOOB, offset, page); this->wait_for_ready(); /* Read the data */ for (i = 0; i < len; i++) buf[i] = this->read_data(); /* De-select the NAND device */ nand_deselect(); /* Return happy */ *retlen = len; return 0;}/* * NAND write */static intnand_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf){ int i, page, col, cnt, status; struct nand_chip *this = mtd->priv; DEBUG(MTD_DEBUG_LEVEL3, __FUNCTION__"(): to = 0x%08x, len = %i\n", (unsigned int)to, (int) len); /* Do not allow write past end of page */ if ((to + len) > mtd->size) { DEBUG(MTD_DEBUG_LEVEL0, __FUNCTION__"(): Attempted write past end of device\n"); return -EINVAL; } /* Shift to get page */ page = ((int)to) >> this->page_shift; /* Get the starting column */ col = to & (mtd->oobblock - 1); /* Initialize return length value */ *retlen = 0; /* Select the NAND device */ nand_select(); /* Check the WP bit */ nand_command(mtd, NAND_CMD_STATUS, -1, -1); this->wait_for_ready(); if (!(this->read_data() & SMC_STAT_NOT_WP)) { DEBUG(MTD_DEBUG_LEVEL0, __FUNCTION__"(): Device is write protected!!!\n"); i = -EPERM; goto nand_write_exit; } /* Loop until all data is written */ while (*retlen < len) { /* Write data into buffer */ if ((col + len) >= mtd->oobblock) for (i = col, cnt = 0; i < mtd->oobblock; i++, cnt++) this->data_buf[i] = buf[(*retlen + cnt)]; else for (i = col, cnt = 0; cnt < (len - *retlen); i++, cnt++) this->data_buf[i] = buf[(*retlen + cnt)]; /* Write ones for partial page programming */ for (i = mtd->oobblock; i < (mtd->oobblock + mtd->oobsize); i++) this->data_buf[i] = 0xff; /* Write pre-padding bytes into buffer */ for (i = 0; i < col; i++) this->data_buf[i] = 0xff; /* Write post-padding bytes into buffer */ if ((col + (len - *retlen)) < mtd->oobblock) { for (i = (col + cnt); i < mtd->oobblock; i++) this->data_buf[i] = 0xff; } /* Send command to begin auto page programming */ nand_command(mtd, NAND_CMD_SEQIN, 0x00, page); /* Write out complete page of data */ this->hwcontrol(NAND_CTL_DAT_OUT); for (i = 0; i < (mtd->oobblock + mtd->oobsize); i++) this->write_data(this->data_buf[i]); this->hwcontrol(NAND_CTL_DAT_IN); /* Send command to actually program the data */ nand_command(mtd, NAND_CMD_PAGEPROG, -1, -1); this->wait_for_ready(); /* * Wait for program operation to complete. This could * take up to 3000us (3ms) on some devices. so we try * and exit as quickly as possible. */ status = 0; for (i = 0; i < 24; i++) { /* Delay for 125us */ udelay(125); /* Check for status */ nand_command(mtd, NAND_CMD_STATUS, -1, -1); status = (int)this->read_data(); if (status & SMC_STAT_READY) break; } /* See if device thinks it succeeded */ if (status & SMC_STAT_WRITE_ERR) { DEBUG(MTD_DEBUG_LEVEL0, __FUNCTION__"(): Failed write, page 0x%08x, " \ "%6i bytes were sucesful\n", page, *retlen); i = -EIO; goto nand_write_exit; }#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
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