diff options
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/nand/davinci_nand.c | 200 |
1 files changed, 146 insertions, 54 deletions
diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c index 41a95685f6..d3c6e51ba8 100644 --- a/drivers/mtd/nand/davinci_nand.c +++ b/drivers/mtd/nand/davinci_nand.c @@ -59,14 +59,111 @@ static emif_registers *const emif_regs = (void *) DAVINCI_ASYNC_EMIF_CNTRL_BASE; +/* + * Exploit the little endianness of the ARM to do multi-byte transfers + * per device read. This can perform over twice as quickly as individual + * byte transfers when buffer alignment is conducive. + * + * NOTE: This only works if the NAND is not connected to the 2 LSBs of + * the address bus. On Davinci EVM platforms this has always been true. + */ +static void nand_davinci_read_buf(struct mtd_info *mtd, uint8_t *buf, int len) +{ + struct nand_chip *chip = mtd->priv; + const u32 *nand = chip->IO_ADDR_R; + + /* Make sure that buf is 32 bit aligned */ + if (((int)buf & 0x3) != 0) { + if (((int)buf & 0x1) != 0) { + if (len) { + *buf = readb(nand); + buf += 1; + len--; + } + } + + if (((int)buf & 0x3) != 0) { + if (len >= 2) { + *(u16 *)buf = readw(nand); + buf += 2; + len -= 2; + } + } + } + + /* copy aligned data */ + while (len >= 4) { + *(u32 *)buf = readl(nand); + buf += 4; + len -= 4; + } + + /* mop up any remaining bytes */ + if (len) { + if (len >= 2) { + *(u16 *)buf = readw(nand); + buf += 2; + len -= 2; + } + + if (len) + *buf = readb(nand); + } +} + +static void nand_davinci_write_buf(struct mtd_info *mtd, const uint8_t *buf, + int len) +{ + struct nand_chip *chip = mtd->priv; + const u32 *nand = chip->IO_ADDR_W; + + /* Make sure that buf is 32 bit aligned */ + if (((int)buf & 0x3) != 0) { + if (((int)buf & 0x1) != 0) { + if (len) { + writeb(*buf, nand); + buf += 1; + len--; + } + } + + if (((int)buf & 0x3) != 0) { + if (len >= 2) { + writew(*(u16 *)buf, nand); + buf += 2; + len -= 2; + } + } + } + + /* copy aligned data */ + while (len >= 4) { + writel(*(u32 *)buf, nand); + buf += 4; + len -= 4; + } + + /* mop up any remaining bytes */ + if (len) { + if (len >= 2) { + writew(*(u16 *)buf, nand); + buf += 2; + len -= 2; + } + + if (len) + writeb(*buf, nand); + } +} + static void nand_davinci_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl) { struct nand_chip *this = mtd->priv; u_int32_t IO_ADDR_W = (u_int32_t)this->IO_ADDR_W; - IO_ADDR_W &= ~(MASK_ALE|MASK_CLE); - if (ctrl & NAND_CTRL_CHANGE) { + IO_ADDR_W &= ~(MASK_ALE|MASK_CLE); + if ( ctrl & NAND_CLE ) IO_ADDR_W |= MASK_CLE; if ( ctrl & NAND_ALE ) @@ -75,7 +172,7 @@ static void nand_davinci_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int c } if (cmd != NAND_CMD_NONE) - writeb(cmd, this->IO_ADDR_W); + writeb(cmd, IO_ADDR_W); } #ifdef CONFIG_SYS_NAND_HW_ECC @@ -248,59 +345,55 @@ static int nand_davinci_4bit_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat, uint8_t *ecc_code) { - unsigned int hw_4ecc[4] = { 0, 0, 0, 0 }; - unsigned int const1 = 0, const2 = 0; - unsigned char count1 = 0; + unsigned int hw_4ecc[4]; + unsigned int i; nand_davinci_4bit_readecc(mtd, hw_4ecc); /*Convert 10 bit ecc value to 8 bit */ - for (count1 = 0; count1 < 2; count1++) { - const2 = count1 * 5; - const1 = count1 * 2; + for (i = 0; i < 2; i++) { + unsigned int hw_ecc_low = hw_4ecc[i * 2]; + unsigned int hw_ecc_hi = hw_4ecc[(i * 2) + 1]; /* Take first 8 bits from val1 (count1=0) or val5 (count1=1) */ - ecc_code[const2] = hw_4ecc[const1] & 0xFF; + *ecc_code++ = hw_ecc_low & 0xFF; /* * Take 2 bits as LSB bits from val1 (count1=0) or val5 * (count1=1) and 6 bits from val2 (count1=0) or * val5 (count1=1) */ - ecc_code[const2 + 1] = - ((hw_4ecc[const1] >> 8) & 0x3) | ((hw_4ecc[const1] >> 14) & - 0xFC); + *ecc_code++ = + ((hw_ecc_low >> 8) & 0x3) | ((hw_ecc_low >> 14) & 0xFC); /* * Take 4 bits from val2 (count1=0) or val5 (count1=1) and * 4 bits from val3 (count1=0) or val6 (count1=1) */ - ecc_code[const2 + 2] = - ((hw_4ecc[const1] >> 22) & 0xF) | - ((hw_4ecc[const1 + 1] << 4) & 0xF0); + *ecc_code++ = + ((hw_ecc_low >> 22) & 0xF) | ((hw_ecc_hi << 4) & 0xF0); /* * Take 6 bits from val3(count1=0) or val6 (count1=1) and * 2 bits from val4 (count1=0) or val7 (count1=1) */ - ecc_code[const2 + 3] = - ((hw_4ecc[const1 + 1] >> 4) & 0x3F) | - ((hw_4ecc[const1 + 1] >> 10) & 0xC0); + *ecc_code++ = + ((hw_ecc_hi >> 4) & 0x3F) | ((hw_ecc_hi >> 10) & 0xC0); /* Take 8 bits from val4 (count1=0) or val7 (count1=1) */ - ecc_code[const2 + 4] = (hw_4ecc[const1 + 1] >> 18) & 0xFF; + *ecc_code++ = (hw_ecc_hi >> 18) & 0xFF; } + return 0; } - static int nand_davinci_4bit_correct_data(struct mtd_info *mtd, uint8_t *dat, uint8_t *read_ecc, uint8_t *calc_ecc) { - unsigned short ecc_10bit[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; int i; - unsigned int hw_4ecc[4] = { 0, 0, 0, 0 }, iserror = 0; - unsigned short *pspare = NULL, *pspare1 = NULL; + unsigned int hw_4ecc[4]; + unsigned int iserror; + unsigned short *ecc16; unsigned int numerrors, erroraddress, errorvalue; u32 val; @@ -317,44 +410,41 @@ static int nand_davinci_4bit_correct_data(struct mtd_info *mtd, uint8_t *dat, return 0; /* Convert 8 bit in to 10 bit */ - pspare = (unsigned short *)&read_ecc[2]; - pspare1 = (unsigned short *)&read_ecc[0]; + ecc16 = (unsigned short *)&read_ecc[0]; - /* Take 10 bits from 0th and 1st bytes */ - ecc_10bit[0] = (*pspare1) & 0x3FF; + /* + * Write the parity values in the NAND Flash 4-bit ECC Load register. + * Write each parity value one at a time starting from 4bit_ecc_val8 + * to 4bit_ecc_val1. + */ - /* Take 6 bits from 1st byte and 4 bits from 2nd byte */ - ecc_10bit[1] = (((*pspare1) >> 10) & 0x3F) - | (((pspare[0]) << 6) & 0x3C0); + /*Take 2 bits from 8th byte and 8 bits from 9th byte */ + writel(((ecc16[4]) >> 6) & 0x3FF, &emif_regs->NAND4BITECCLOAD); - /* Take 4 bits form 2nd bytes and 6 bits from 3rd bytes */ - ecc_10bit[2] = ((pspare[0]) >> 4) & 0x3FF; + /* Take 4 bits from 7th byte and 6 bits from 8th byte */ + writel((((ecc16[3]) >> 12) & 0xF) | ((((ecc16[4])) << 4) & 0x3F0), + &emif_regs->NAND4BITECCLOAD); - /*Take 2 bits from 3rd byte and 8 bits from 4th byte */ - ecc_10bit[3] = (((pspare[0]) >> 14) & 0x3) - | ((((pspare[1])) << 2) & 0x3FC); + /* Take 6 bits from 6th byte and 4 bits from 7th byte */ + writel((ecc16[3] >> 2) & 0x3FF, &emif_regs->NAND4BITECCLOAD); /* Take 8 bits from 5th byte and 2 bits from 6th byte */ - ecc_10bit[4] = ((pspare[1]) >> 8) - | ((((pspare[2])) << 8) & 0x300); + writel(((ecc16[2]) >> 8) | ((((ecc16[3])) << 8) & 0x300), + &emif_regs->NAND4BITECCLOAD); - /* Take 6 bits from 6th byte and 4 bits from 7th byte */ - ecc_10bit[5] = (pspare[2] >> 2) & 0x3FF; + /*Take 2 bits from 3rd byte and 8 bits from 4th byte */ + writel((((ecc16[1]) >> 14) & 0x3) | ((((ecc16[2])) << 2) & 0x3FC), + &emif_regs->NAND4BITECCLOAD); - /* Take 4 bits from 7th byte and 6 bits from 8th byte */ - ecc_10bit[6] = (((pspare[2]) >> 12) & 0xF) - | ((((pspare[3])) << 4) & 0x3F0); + /* Take 4 bits form 2nd bytes and 6 bits from 3rd bytes */ + writel(((ecc16[1]) >> 4) & 0x3FF, &emif_regs->NAND4BITECCLOAD); - /*Take 2 bits from 8th byte and 8 bits from 9th byte */ - ecc_10bit[7] = ((pspare[3]) >> 6) & 0x3FF; + /* Take 6 bits from 1st byte and 4 bits from 2nd byte */ + writel((((ecc16[0]) >> 10) & 0x3F) | (((ecc16[1]) << 6) & 0x3C0), + &emif_regs->NAND4BITECCLOAD); - /* - * Write the parity values in the NAND Flash 4-bit ECC Load register. - * Write each parity value one at a time starting from 4bit_ecc_val8 - * to 4bit_ecc_val1. - */ - for (i = 7; i >= 0; i--) - emif_regs->NAND4BITECCLOAD = ecc_10bit[i]; + /* Take 10 bits from 0th and 1st bytes */ + writel((ecc16[0]) & 0x3FF, &emif_regs->NAND4BITECCLOAD); /* * Perform a dummy read to the EMIF Revision Code and Status register. @@ -371,8 +461,7 @@ static int nand_davinci_4bit_correct_data(struct mtd_info *mtd, uint8_t *dat, */ nand_davinci_4bit_readecc(mtd, hw_4ecc); - if (hw_4ecc[0] == ECC_STATE_NO_ERR && hw_4ecc[1] == ECC_STATE_NO_ERR && - hw_4ecc[2] == ECC_STATE_NO_ERR && hw_4ecc[3] == ECC_STATE_NO_ERR) + if (!(hw_4ecc[0] | hw_4ecc[1] | hw_4ecc[2] | hw_4ecc[3])) return 0; /* @@ -519,6 +608,9 @@ void davinci_nand_init(struct nand_chip *nand) /* Set address of hardware control function */ nand->cmd_ctrl = nand_davinci_hwcontrol; + nand->read_buf = nand_davinci_read_buf; + nand->write_buf = nand_davinci_write_buf; + nand->dev_ready = nand_davinci_dev_ready; nand_flash_init(); |