linux/drivers/mtd/nand/davinci_nand.c
Mike Dunn 6a918bade9 mtd: flash drivers set ecc strength
Flash device drivers initialize 'ecc_strength' in struct mtd_info, which is the
maximum number of bit errors that can be corrected in one writesize region.

Drivers using the nand interface intitialize 'strength' in struct nand_ecc_ctrl,
which is the maximum number of bit errors that can be corrected in one ecc step.
Nand infrastructure code translates this to 'ecc_strength'.

Also for nand drivers, the nand infrastructure code sets ecc.strength for ecc
modes NAND_ECC_SOFT, NAND_ECC_SOFT_BCH, and NAND_ECC_NONE.  It is set in the
driver for all other modes.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:56:46 +01:00

839 lines
23 KiB
C

/*
* davinci_nand.c - NAND Flash Driver for DaVinci family chips
*
* Copyright © 2006 Texas Instruments.
*
* Port to 2.6.23 Copyright © 2008 by:
* Sander Huijsen <Shuijsen@optelecom-nkf.com>
* Troy Kisky <troy.kisky@boundarydevices.com>
* Dirk Behme <Dirk.Behme@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/slab.h>
#include <mach/nand.h>
#include <mach/aemif.h>
/*
* This is a device driver for the NAND flash controller found on the
* various DaVinci family chips. It handles up to four SoC chipselects,
* and some flavors of secondary chipselect (e.g. based on A12) as used
* with multichip packages.
*
* The 1-bit ECC hardware is supported, as well as the newer 4-bit ECC
* available on chips like the DM355 and OMAP-L137 and needed with the
* more error-prone MLC NAND chips.
*
* This driver assumes EM_WAIT connects all the NAND devices' RDY/nBUSY
* outputs in a "wire-AND" configuration, with no per-chip signals.
*/
struct davinci_nand_info {
struct mtd_info mtd;
struct nand_chip chip;
struct nand_ecclayout ecclayout;
struct device *dev;
struct clk *clk;
bool is_readmode;
void __iomem *base;
void __iomem *vaddr;
uint32_t ioaddr;
uint32_t current_cs;
uint32_t mask_chipsel;
uint32_t mask_ale;
uint32_t mask_cle;
uint32_t core_chipsel;
struct davinci_aemif_timing *timing;
};
static DEFINE_SPINLOCK(davinci_nand_lock);
static bool ecc4_busy;
#define to_davinci_nand(m) container_of(m, struct davinci_nand_info, mtd)
static inline unsigned int davinci_nand_readl(struct davinci_nand_info *info,
int offset)
{
return __raw_readl(info->base + offset);
}
static inline void davinci_nand_writel(struct davinci_nand_info *info,
int offset, unsigned long value)
{
__raw_writel(value, info->base + offset);
}
/*----------------------------------------------------------------------*/
/*
* Access to hardware control lines: ALE, CLE, secondary chipselect.
*/
static void nand_davinci_hwcontrol(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
uint32_t addr = info->current_cs;
struct nand_chip *nand = mtd->priv;
/* Did the control lines change? */
if (ctrl & NAND_CTRL_CHANGE) {
if ((ctrl & NAND_CTRL_CLE) == NAND_CTRL_CLE)
addr |= info->mask_cle;
else if ((ctrl & NAND_CTRL_ALE) == NAND_CTRL_ALE)
addr |= info->mask_ale;
nand->IO_ADDR_W = (void __iomem __force *)addr;
}
if (cmd != NAND_CMD_NONE)
iowrite8(cmd, nand->IO_ADDR_W);
}
static void nand_davinci_select_chip(struct mtd_info *mtd, int chip)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
uint32_t addr = info->ioaddr;
/* maybe kick in a second chipselect */
if (chip > 0)
addr |= info->mask_chipsel;
info->current_cs = addr;
info->chip.IO_ADDR_W = (void __iomem __force *)addr;
info->chip.IO_ADDR_R = info->chip.IO_ADDR_W;
}
/*----------------------------------------------------------------------*/
/*
* 1-bit hardware ECC ... context maintained for each core chipselect
*/
static inline uint32_t nand_davinci_readecc_1bit(struct mtd_info *mtd)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
return davinci_nand_readl(info, NANDF1ECC_OFFSET
+ 4 * info->core_chipsel);
}
static void nand_davinci_hwctl_1bit(struct mtd_info *mtd, int mode)
{
struct davinci_nand_info *info;
uint32_t nandcfr;
unsigned long flags;
info = to_davinci_nand(mtd);
/* Reset ECC hardware */
nand_davinci_readecc_1bit(mtd);
spin_lock_irqsave(&davinci_nand_lock, flags);
/* Restart ECC hardware */
nandcfr = davinci_nand_readl(info, NANDFCR_OFFSET);
nandcfr |= BIT(8 + info->core_chipsel);
davinci_nand_writel(info, NANDFCR_OFFSET, nandcfr);
spin_unlock_irqrestore(&davinci_nand_lock, flags);
}
/*
* Read hardware ECC value and pack into three bytes
*/
static int nand_davinci_calculate_1bit(struct mtd_info *mtd,
const u_char *dat, u_char *ecc_code)
{
unsigned int ecc_val = nand_davinci_readecc_1bit(mtd);
unsigned int ecc24 = (ecc_val & 0x0fff) | ((ecc_val & 0x0fff0000) >> 4);
/* invert so that erased block ecc is correct */
ecc24 = ~ecc24;
ecc_code[0] = (u_char)(ecc24);
ecc_code[1] = (u_char)(ecc24 >> 8);
ecc_code[2] = (u_char)(ecc24 >> 16);
return 0;
}
static int nand_davinci_correct_1bit(struct mtd_info *mtd, u_char *dat,
u_char *read_ecc, u_char *calc_ecc)
{
struct nand_chip *chip = mtd->priv;
uint32_t eccNand = read_ecc[0] | (read_ecc[1] << 8) |
(read_ecc[2] << 16);
uint32_t eccCalc = calc_ecc[0] | (calc_ecc[1] << 8) |
(calc_ecc[2] << 16);
uint32_t diff = eccCalc ^ eccNand;
if (diff) {
if ((((diff >> 12) ^ diff) & 0xfff) == 0xfff) {
/* Correctable error */
if ((diff >> (12 + 3)) < chip->ecc.size) {
dat[diff >> (12 + 3)] ^= BIT((diff >> 12) & 7);
return 1;
} else {
return -1;
}
} else if (!(diff & (diff - 1))) {
/* Single bit ECC error in the ECC itself,
* nothing to fix */
return 1;
} else {
/* Uncorrectable error */
return -1;
}
}
return 0;
}
/*----------------------------------------------------------------------*/
/*
* 4-bit hardware ECC ... context maintained over entire AEMIF
*
* This is a syndrome engine, but we avoid NAND_ECC_HW_SYNDROME
* since that forces use of a problematic "infix OOB" layout.
* Among other things, it trashes manufacturer bad block markers.
* Also, and specific to this hardware, it ECC-protects the "prepad"
* in the OOB ... while having ECC protection for parts of OOB would
* seem useful, the current MTD stack sometimes wants to update the
* OOB without recomputing ECC.
*/
static void nand_davinci_hwctl_4bit(struct mtd_info *mtd, int mode)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
unsigned long flags;
u32 val;
spin_lock_irqsave(&davinci_nand_lock, flags);
/* Start 4-bit ECC calculation for read/write */
val = davinci_nand_readl(info, NANDFCR_OFFSET);
val &= ~(0x03 << 4);
val |= (info->core_chipsel << 4) | BIT(12);
davinci_nand_writel(info, NANDFCR_OFFSET, val);
info->is_readmode = (mode == NAND_ECC_READ);
spin_unlock_irqrestore(&davinci_nand_lock, flags);
}
/* Read raw ECC code after writing to NAND. */
static void
nand_davinci_readecc_4bit(struct davinci_nand_info *info, u32 code[4])
{
const u32 mask = 0x03ff03ff;
code[0] = davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET) & mask;
code[1] = davinci_nand_readl(info, NAND_4BIT_ECC2_OFFSET) & mask;
code[2] = davinci_nand_readl(info, NAND_4BIT_ECC3_OFFSET) & mask;
code[3] = davinci_nand_readl(info, NAND_4BIT_ECC4_OFFSET) & mask;
}
/* Terminate read ECC; or return ECC (as bytes) of data written to NAND. */
static int nand_davinci_calculate_4bit(struct mtd_info *mtd,
const u_char *dat, u_char *ecc_code)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
u32 raw_ecc[4], *p;
unsigned i;
/* After a read, terminate ECC calculation by a dummy read
* of some 4-bit ECC register. ECC covers everything that
* was read; correct() just uses the hardware state, so
* ecc_code is not needed.
*/
if (info->is_readmode) {
davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET);
return 0;
}
/* Pack eight raw 10-bit ecc values into ten bytes, making
* two passes which each convert four values (in upper and
* lower halves of two 32-bit words) into five bytes. The
* ROM boot loader uses this same packing scheme.
*/
nand_davinci_readecc_4bit(info, raw_ecc);
for (i = 0, p = raw_ecc; i < 2; i++, p += 2) {
*ecc_code++ = p[0] & 0xff;
*ecc_code++ = ((p[0] >> 8) & 0x03) | ((p[0] >> 14) & 0xfc);
*ecc_code++ = ((p[0] >> 22) & 0x0f) | ((p[1] << 4) & 0xf0);
*ecc_code++ = ((p[1] >> 4) & 0x3f) | ((p[1] >> 10) & 0xc0);
*ecc_code++ = (p[1] >> 18) & 0xff;
}
return 0;
}
/* Correct up to 4 bits in data we just read, using state left in the
* hardware plus the ecc_code computed when it was first written.
*/
static int nand_davinci_correct_4bit(struct mtd_info *mtd,
u_char *data, u_char *ecc_code, u_char *null)
{
int i;
struct davinci_nand_info *info = to_davinci_nand(mtd);
unsigned short ecc10[8];
unsigned short *ecc16;
u32 syndrome[4];
u32 ecc_state;
unsigned num_errors, corrected;
unsigned long timeo;
/* All bytes 0xff? It's an erased page; ignore its ECC. */
for (i = 0; i < 10; i++) {
if (ecc_code[i] != 0xff)
goto compare;
}
return 0;
compare:
/* Unpack ten bytes into eight 10 bit values. We know we're
* little-endian, and use type punning for less shifting/masking.
*/
if (WARN_ON(0x01 & (unsigned) ecc_code))
return -EINVAL;
ecc16 = (unsigned short *)ecc_code;
ecc10[0] = (ecc16[0] >> 0) & 0x3ff;
ecc10[1] = ((ecc16[0] >> 10) & 0x3f) | ((ecc16[1] << 6) & 0x3c0);
ecc10[2] = (ecc16[1] >> 4) & 0x3ff;
ecc10[3] = ((ecc16[1] >> 14) & 0x3) | ((ecc16[2] << 2) & 0x3fc);
ecc10[4] = (ecc16[2] >> 8) | ((ecc16[3] << 8) & 0x300);
ecc10[5] = (ecc16[3] >> 2) & 0x3ff;
ecc10[6] = ((ecc16[3] >> 12) & 0xf) | ((ecc16[4] << 4) & 0x3f0);
ecc10[7] = (ecc16[4] >> 6) & 0x3ff;
/* Tell ECC controller about the expected ECC codes. */
for (i = 7; i >= 0; i--)
davinci_nand_writel(info, NAND_4BIT_ECC_LOAD_OFFSET, ecc10[i]);
/* Allow time for syndrome calculation ... then read it.
* A syndrome of all zeroes 0 means no detected errors.
*/
davinci_nand_readl(info, NANDFSR_OFFSET);
nand_davinci_readecc_4bit(info, syndrome);
if (!(syndrome[0] | syndrome[1] | syndrome[2] | syndrome[3]))
return 0;
/*
* Clear any previous address calculation by doing a dummy read of an
* error address register.
*/
davinci_nand_readl(info, NAND_ERR_ADD1_OFFSET);
/* Start address calculation, and wait for it to complete.
* We _could_ start reading more data while this is working,
* to speed up the overall page read.
*/
davinci_nand_writel(info, NANDFCR_OFFSET,
davinci_nand_readl(info, NANDFCR_OFFSET) | BIT(13));
/*
* ECC_STATE field reads 0x3 (Error correction complete) immediately
* after setting the 4BITECC_ADD_CALC_START bit. So if you immediately
* begin trying to poll for the state, you may fall right out of your
* loop without any of the correction calculations having taken place.
* The recommendation from the hardware team is to initially delay as
* long as ECC_STATE reads less than 4. After that, ECC HW has entered
* correction state.
*/
timeo = jiffies + usecs_to_jiffies(100);
do {
ecc_state = (davinci_nand_readl(info,
NANDFSR_OFFSET) >> 8) & 0x0f;
cpu_relax();
} while ((ecc_state < 4) && time_before(jiffies, timeo));
for (;;) {
u32 fsr = davinci_nand_readl(info, NANDFSR_OFFSET);
switch ((fsr >> 8) & 0x0f) {
case 0: /* no error, should not happen */
davinci_nand_readl(info, NAND_ERR_ERRVAL1_OFFSET);
return 0;
case 1: /* five or more errors detected */
davinci_nand_readl(info, NAND_ERR_ERRVAL1_OFFSET);
return -EIO;
case 2: /* error addresses computed */
case 3:
num_errors = 1 + ((fsr >> 16) & 0x03);
goto correct;
default: /* still working on it */
cpu_relax();
continue;
}
}
correct:
/* correct each error */
for (i = 0, corrected = 0; i < num_errors; i++) {
int error_address, error_value;
if (i > 1) {
error_address = davinci_nand_readl(info,
NAND_ERR_ADD2_OFFSET);
error_value = davinci_nand_readl(info,
NAND_ERR_ERRVAL2_OFFSET);
} else {
error_address = davinci_nand_readl(info,
NAND_ERR_ADD1_OFFSET);
error_value = davinci_nand_readl(info,
NAND_ERR_ERRVAL1_OFFSET);
}
if (i & 1) {
error_address >>= 16;
error_value >>= 16;
}
error_address &= 0x3ff;
error_address = (512 + 7) - error_address;
if (error_address < 512) {
data[error_address] ^= error_value;
corrected++;
}
}
return corrected;
}
/*----------------------------------------------------------------------*/
/*
* NOTE: NAND boot requires ALE == EM_A[1], CLE == EM_A[2], so that's
* how these chips are normally wired. This translates to both 8 and 16
* bit busses using ALE == BIT(3) in byte addresses, and CLE == BIT(4).
*
* For now we assume that configuration, or any other one which ignores
* the two LSBs for NAND access ... so we can issue 32-bit reads/writes
* and have that transparently morphed into multiple NAND operations.
*/
static void nand_davinci_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
struct nand_chip *chip = mtd->priv;
if ((0x03 & ((unsigned)buf)) == 0 && (0x03 & len) == 0)
ioread32_rep(chip->IO_ADDR_R, buf, len >> 2);
else if ((0x01 & ((unsigned)buf)) == 0 && (0x01 & len) == 0)
ioread16_rep(chip->IO_ADDR_R, buf, len >> 1);
else
ioread8_rep(chip->IO_ADDR_R, buf, len);
}
static void nand_davinci_write_buf(struct mtd_info *mtd,
const uint8_t *buf, int len)
{
struct nand_chip *chip = mtd->priv;
if ((0x03 & ((unsigned)buf)) == 0 && (0x03 & len) == 0)
iowrite32_rep(chip->IO_ADDR_R, buf, len >> 2);
else if ((0x01 & ((unsigned)buf)) == 0 && (0x01 & len) == 0)
iowrite16_rep(chip->IO_ADDR_R, buf, len >> 1);
else
iowrite8_rep(chip->IO_ADDR_R, buf, len);
}
/*
* Check hardware register for wait status. Returns 1 if device is ready,
* 0 if it is still busy.
*/
static int nand_davinci_dev_ready(struct mtd_info *mtd)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
return davinci_nand_readl(info, NANDFSR_OFFSET) & BIT(0);
}
/*----------------------------------------------------------------------*/
/* An ECC layout for using 4-bit ECC with small-page flash, storing
* ten ECC bytes plus the manufacturer's bad block marker byte, and
* and not overlapping the default BBT markers.
*/
static struct nand_ecclayout hwecc4_small __initconst = {
.eccbytes = 10,
.eccpos = { 0, 1, 2, 3, 4,
/* offset 5 holds the badblock marker */
6, 7,
13, 14, 15, },
.oobfree = {
{.offset = 8, .length = 5, },
{.offset = 16, },
},
};
/* An ECC layout for using 4-bit ECC with large-page (2048bytes) flash,
* storing ten ECC bytes plus the manufacturer's bad block marker byte,
* and not overlapping the default BBT markers.
*/
static struct nand_ecclayout hwecc4_2048 __initconst = {
.eccbytes = 40,
.eccpos = {
/* at the end of spare sector */
24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
34, 35, 36, 37, 38, 39, 40, 41, 42, 43,
44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
},
.oobfree = {
/* 2 bytes at offset 0 hold manufacturer badblock markers */
{.offset = 2, .length = 22, },
/* 5 bytes at offset 8 hold BBT markers */
/* 8 bytes at offset 16 hold JFFS2 clean markers */
},
};
static int __init nand_davinci_probe(struct platform_device *pdev)
{
struct davinci_nand_pdata *pdata = pdev->dev.platform_data;
struct davinci_nand_info *info;
struct resource *res1;
struct resource *res2;
void __iomem *vaddr;
void __iomem *base;
int ret;
uint32_t val;
nand_ecc_modes_t ecc_mode;
/* insist on board-specific configuration */
if (!pdata)
return -ENODEV;
/* which external chipselect will we be managing? */
if (pdev->id < 0 || pdev->id > 3)
return -ENODEV;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info) {
dev_err(&pdev->dev, "unable to allocate memory\n");
ret = -ENOMEM;
goto err_nomem;
}
platform_set_drvdata(pdev, info);
res1 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
res2 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!res1 || !res2) {
dev_err(&pdev->dev, "resource missing\n");
ret = -EINVAL;
goto err_nomem;
}
vaddr = ioremap(res1->start, resource_size(res1));
base = ioremap(res2->start, resource_size(res2));
if (!vaddr || !base) {
dev_err(&pdev->dev, "ioremap failed\n");
ret = -EINVAL;
goto err_ioremap;
}
info->dev = &pdev->dev;
info->base = base;
info->vaddr = vaddr;
info->mtd.priv = &info->chip;
info->mtd.name = dev_name(&pdev->dev);
info->mtd.owner = THIS_MODULE;
info->mtd.dev.parent = &pdev->dev;
info->chip.IO_ADDR_R = vaddr;
info->chip.IO_ADDR_W = vaddr;
info->chip.chip_delay = 0;
info->chip.select_chip = nand_davinci_select_chip;
/* options such as NAND_BBT_USE_FLASH */
info->chip.bbt_options = pdata->bbt_options;
/* options such as 16-bit widths */
info->chip.options = pdata->options;
info->chip.bbt_td = pdata->bbt_td;
info->chip.bbt_md = pdata->bbt_md;
info->timing = pdata->timing;
info->ioaddr = (uint32_t __force) vaddr;
info->current_cs = info->ioaddr;
info->core_chipsel = pdev->id;
info->mask_chipsel = pdata->mask_chipsel;
/* use nandboot-capable ALE/CLE masks by default */
info->mask_ale = pdata->mask_ale ? : MASK_ALE;
info->mask_cle = pdata->mask_cle ? : MASK_CLE;
/* Set address of hardware control function */
info->chip.cmd_ctrl = nand_davinci_hwcontrol;
info->chip.dev_ready = nand_davinci_dev_ready;
/* Speed up buffer I/O */
info->chip.read_buf = nand_davinci_read_buf;
info->chip.write_buf = nand_davinci_write_buf;
/* Use board-specific ECC config */
ecc_mode = pdata->ecc_mode;
ret = -EINVAL;
switch (ecc_mode) {
case NAND_ECC_NONE:
case NAND_ECC_SOFT:
pdata->ecc_bits = 0;
break;
case NAND_ECC_HW:
if (pdata->ecc_bits == 4) {
/* No sanity checks: CPUs must support this,
* and the chips may not use NAND_BUSWIDTH_16.
*/
/* No sharing 4-bit hardware between chipselects yet */
spin_lock_irq(&davinci_nand_lock);
if (ecc4_busy)
ret = -EBUSY;
else
ecc4_busy = true;
spin_unlock_irq(&davinci_nand_lock);
if (ret == -EBUSY)
goto err_ecc;
info->chip.ecc.calculate = nand_davinci_calculate_4bit;
info->chip.ecc.correct = nand_davinci_correct_4bit;
info->chip.ecc.hwctl = nand_davinci_hwctl_4bit;
info->chip.ecc.bytes = 10;
} else {
info->chip.ecc.calculate = nand_davinci_calculate_1bit;
info->chip.ecc.correct = nand_davinci_correct_1bit;
info->chip.ecc.hwctl = nand_davinci_hwctl_1bit;
info->chip.ecc.bytes = 3;
}
info->chip.ecc.size = 512;
info->chip.ecc.strength = pdata->ecc_bits;
break;
default:
ret = -EINVAL;
goto err_ecc;
}
info->chip.ecc.mode = ecc_mode;
info->clk = clk_get(&pdev->dev, "aemif");
if (IS_ERR(info->clk)) {
ret = PTR_ERR(info->clk);
dev_dbg(&pdev->dev, "unable to get AEMIF clock, err %d\n", ret);
goto err_clk;
}
ret = clk_enable(info->clk);
if (ret < 0) {
dev_dbg(&pdev->dev, "unable to enable AEMIF clock, err %d\n",
ret);
goto err_clk_enable;
}
/*
* Setup Async configuration register in case we did not boot from
* NAND and so bootloader did not bother to set it up.
*/
val = davinci_nand_readl(info, A1CR_OFFSET + info->core_chipsel * 4);
/* Extended Wait is not valid and Select Strobe mode is not used */
val &= ~(ACR_ASIZE_MASK | ACR_EW_MASK | ACR_SS_MASK);
if (info->chip.options & NAND_BUSWIDTH_16)
val |= 0x1;
davinci_nand_writel(info, A1CR_OFFSET + info->core_chipsel * 4, val);
ret = 0;
if (info->timing)
ret = davinci_aemif_setup_timing(info->timing, info->base,
info->core_chipsel);
if (ret < 0) {
dev_dbg(&pdev->dev, "NAND timing values setup fail\n");
goto err_timing;
}
spin_lock_irq(&davinci_nand_lock);
/* put CSxNAND into NAND mode */
val = davinci_nand_readl(info, NANDFCR_OFFSET);
val |= BIT(info->core_chipsel);
davinci_nand_writel(info, NANDFCR_OFFSET, val);
spin_unlock_irq(&davinci_nand_lock);
/* Scan to find existence of the device(s) */
ret = nand_scan_ident(&info->mtd, pdata->mask_chipsel ? 2 : 1, NULL);
if (ret < 0) {
dev_dbg(&pdev->dev, "no NAND chip(s) found\n");
goto err_scan;
}
/* Update ECC layout if needed ... for 1-bit HW ECC, the default
* is OK, but it allocates 6 bytes when only 3 are needed (for
* each 512 bytes). For the 4-bit HW ECC, that default is not
* usable: 10 bytes are needed, not 6.
*/
if (pdata->ecc_bits == 4) {
int chunks = info->mtd.writesize / 512;
if (!chunks || info->mtd.oobsize < 16) {
dev_dbg(&pdev->dev, "too small\n");
ret = -EINVAL;
goto err_scan;
}
/* For small page chips, preserve the manufacturer's
* badblock marking data ... and make sure a flash BBT
* table marker fits in the free bytes.
*/
if (chunks == 1) {
info->ecclayout = hwecc4_small;
info->ecclayout.oobfree[1].length =
info->mtd.oobsize - 16;
goto syndrome_done;
}
if (chunks == 4) {
info->ecclayout = hwecc4_2048;
info->chip.ecc.mode = NAND_ECC_HW_OOB_FIRST;
goto syndrome_done;
}
/* 4KiB page chips are not yet supported. The eccpos from
* nand_ecclayout cannot hold 80 bytes and change to eccpos[]
* breaks userspace ioctl interface with mtd-utils. Once we
* resolve this issue, NAND_ECC_HW_OOB_FIRST mode can be used
* for the 4KiB page chips.
*
* TODO: Note that nand_ecclayout has now been expanded and can
* hold plenty of OOB entries.
*/
dev_warn(&pdev->dev, "no 4-bit ECC support yet "
"for 4KiB-page NAND\n");
ret = -EIO;
goto err_scan;
syndrome_done:
info->chip.ecc.layout = &info->ecclayout;
}
ret = nand_scan_tail(&info->mtd);
if (ret < 0)
goto err_scan;
ret = mtd_device_parse_register(&info->mtd, NULL, NULL, pdata->parts,
pdata->nr_parts);
if (ret < 0)
goto err_scan;
val = davinci_nand_readl(info, NRCSR_OFFSET);
dev_info(&pdev->dev, "controller rev. %d.%d\n",
(val >> 8) & 0xff, val & 0xff);
return 0;
err_scan:
err_timing:
clk_disable(info->clk);
err_clk_enable:
clk_put(info->clk);
spin_lock_irq(&davinci_nand_lock);
if (ecc_mode == NAND_ECC_HW_SYNDROME)
ecc4_busy = false;
spin_unlock_irq(&davinci_nand_lock);
err_ecc:
err_clk:
err_ioremap:
if (base)
iounmap(base);
if (vaddr)
iounmap(vaddr);
err_nomem:
kfree(info);
return ret;
}
static int __exit nand_davinci_remove(struct platform_device *pdev)
{
struct davinci_nand_info *info = platform_get_drvdata(pdev);
spin_lock_irq(&davinci_nand_lock);
if (info->chip.ecc.mode == NAND_ECC_HW_SYNDROME)
ecc4_busy = false;
spin_unlock_irq(&davinci_nand_lock);
iounmap(info->base);
iounmap(info->vaddr);
nand_release(&info->mtd);
clk_disable(info->clk);
clk_put(info->clk);
kfree(info);
return 0;
}
static struct platform_driver nand_davinci_driver = {
.remove = __exit_p(nand_davinci_remove),
.driver = {
.name = "davinci_nand",
},
};
MODULE_ALIAS("platform:davinci_nand");
static int __init nand_davinci_init(void)
{
return platform_driver_probe(&nand_davinci_driver, nand_davinci_probe);
}
module_init(nand_davinci_init);
static void __exit nand_davinci_exit(void)
{
platform_driver_unregister(&nand_davinci_driver);
}
module_exit(nand_davinci_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Texas Instruments");
MODULE_DESCRIPTION("Davinci NAND flash driver");