/*
- * drivers/mtd/nand.c
- *
* Overview:
* This is the generic MTD driver for NAND flash devices. It should be
* capable of working with almost all NAND chips currently available.
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <common.h>
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+#include <fdtdec.h>
+#endif
#include <malloc.h>
#include <watchdog.h>
#include <linux/err.h>
#include <linux/mtd/partitions.h>
#endif
#include <asm/io.h>
-#include <asm/errno.h>
-
-/*
- * CONFIG_SYS_NAND_RESET_CNT is used as a timeout mechanism when resetting
- * a flash. NAND flash is initialized prior to interrupts so standard timers
- * can't be used. CONFIG_SYS_NAND_RESET_CNT should be set to a value
- * which is greater than (max NAND reset time / NAND status read time).
- * A conservative default of 200000 (500 us / 25 ns) is used as a default.
- */
-#ifndef CONFIG_SYS_NAND_RESET_CNT
-#define CONFIG_SYS_NAND_RESET_CNT 200000
-#endif
-
-static bool is_module_text_address(unsigned long addr) {return 0;}
+#include <linux/errno.h>
/* Define default oob placement schemes for large and small page devices */
static struct nand_ecclayout nand_oob_8 = {
static int check_offs_len(struct mtd_info *mtd,
loff_t ofs, uint64_t len)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
int ret = 0;
/* Start address must align on block boundary */
*/
static void nand_release_device(struct mtd_info *mtd)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
/* De-select the NAND device */
chip->select_chip(mtd, -1);
*/
uint8_t nand_read_byte(struct mtd_info *mtd)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
return readb(chip->IO_ADDR_R);
}
/**
- * nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
* nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
* @mtd: MTD device structure
*
*/
static uint8_t nand_read_byte16(struct mtd_info *mtd)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
return (uint8_t) cpu_to_le16(readw(chip->IO_ADDR_R));
}
*/
static u16 nand_read_word(struct mtd_info *mtd)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
return readw(chip->IO_ADDR_R);
}
*/
static void nand_select_chip(struct mtd_info *mtd, int chipnr)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
switch (chipnr) {
case -1:
*/
static void nand_write_byte(struct mtd_info *mtd, uint8_t byte)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
chip->write_buf(mtd, &byte, 1);
}
*/
static void nand_write_byte16(struct mtd_info *mtd, uint8_t byte)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
uint16_t word = byte;
/*
*/
void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
iowrite8_rep(chip->IO_ADDR_W, buf, len);
}
*/
void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
ioread8_rep(chip->IO_ADDR_R, buf, len);
}
*/
void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
u16 *p = (u16 *) buf;
iowrite16_rep(chip->IO_ADDR_W, p, len >> 1);
*/
void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
u16 *p = (u16 *) buf;
ioread16_rep(chip->IO_ADDR_R, p, len >> 1);
* nand_block_bad - [DEFAULT] Read bad block marker from the chip
* @mtd: MTD device structure
* @ofs: offset from device start
- * @getchip: 0, if the chip is already selected
*
* Check, if the block is bad.
*/
-static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
+static int nand_block_bad(struct mtd_info *mtd, loff_t ofs)
{
- int page, chipnr, res = 0, i = 0;
- struct nand_chip *chip = mtd->priv;
+ int page, res = 0, i = 0;
+ struct nand_chip *chip = mtd_to_nand(mtd);
u16 bad;
if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
page = (int)(ofs >> chip->page_shift) & chip->pagemask;
- if (getchip) {
- chipnr = (int)(ofs >> chip->chip_shift);
-
- nand_get_device(mtd, FL_READING);
-
- /* Select the NAND device */
- chip->select_chip(mtd, chipnr);
- }
-
do {
if (chip->options & NAND_BUSWIDTH_16) {
chip->cmdfunc(mtd, NAND_CMD_READOOB,
i++;
} while (!res && i < 2 && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE));
- if (getchip) {
- chip->select_chip(mtd, -1);
- nand_release_device(mtd);
- }
-
return res;
}
*/
static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
struct mtd_oob_ops ops;
uint8_t buf[2] = { 0, 0 };
int ret = 0, res, i = 0;
- ops.datbuf = NULL;
+ memset(&ops, 0, sizeof(ops));
ops.oobbuf = buf;
ops.ooboffs = chip->badblockpos;
if (chip->options & NAND_BUSWIDTH_16) {
*/
static int nand_block_markbad_lowlevel(struct mtd_info *mtd, loff_t ofs)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
int res, ret = 0;
if (!(chip->bbt_options & NAND_BBT_NO_OOB_BBM)) {
*/
static int nand_check_wp(struct mtd_info *mtd)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
/* Broken xD cards report WP despite being writable */
if (chip->options & NAND_BROKEN_XD)
return (chip->read_byte(mtd) & NAND_STATUS_WP) ? 0 : 1;
}
+/**
+ * nand_block_isreserved - [GENERIC] Check if a block is marked reserved.
+ * @mtd: MTD device structure
+ * @ofs: offset from device start
+ *
+ * Check if the block is marked as reserved.
+ */
+static int nand_block_isreserved(struct mtd_info *mtd, loff_t ofs)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+
+ if (!chip->bbt)
+ return 0;
+ /* Return info from the table */
+ return nand_isreserved_bbt(mtd, ofs);
+}
+
/**
* nand_block_checkbad - [GENERIC] Check if a block is marked bad
* @mtd: MTD device structure
* @ofs: offset from device start
- * @getchip: 0, if the chip is already selected
* @allowbbt: 1, if its allowed to access the bbt area
*
* Check, if the block is bad. Either by reading the bad block table or
* calling of the scan function.
*/
-static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
- int allowbbt)
+static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int allowbbt)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
if (!(chip->options & NAND_SKIP_BBTSCAN) &&
!(chip->options & NAND_BBT_SCANNED)) {
}
if (!chip->bbt)
- return chip->block_bad(mtd, ofs, getchip);
+ return chip->block_bad(mtd, ofs);
/* Return info from the table */
return nand_isbad_bbt(mtd, ofs, allowbbt);
}
-/* Wait for the ready pin, after a command. The timeout is caught later. */
+/**
+ * nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
+ * @mtd: MTD device structure
+ *
+ * Wait for the ready pin after a command, and warn if a timeout occurs.
+ */
void nand_wait_ready(struct mtd_info *mtd)
{
- struct nand_chip *chip = mtd->priv;
- u32 timeo = (CONFIG_SYS_HZ * 20) / 1000;
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ u32 timeo = (CONFIG_SYS_HZ * 400) / 1000;
u32 time_start;
time_start = get_timer(0);
if (chip->dev_ready(mtd))
break;
}
+
+ if (!chip->dev_ready(mtd))
+ pr_warn("timeout while waiting for chip to become ready\n");
}
EXPORT_SYMBOL_GPL(nand_wait_ready);
+/**
+ * nand_wait_status_ready - [GENERIC] Wait for the ready status after commands.
+ * @mtd: MTD device structure
+ * @timeo: Timeout in ms
+ *
+ * Wait for status ready (i.e. command done) or timeout.
+ */
+static void nand_wait_status_ready(struct mtd_info *mtd, unsigned long timeo)
+{
+ register struct nand_chip *chip = mtd_to_nand(mtd);
+ u32 time_start;
+
+ timeo = (CONFIG_SYS_HZ * timeo) / 1000;
+ time_start = get_timer(0);
+ while (get_timer(time_start) < timeo) {
+ if ((chip->read_byte(mtd) & NAND_STATUS_READY))
+ break;
+ WATCHDOG_RESET();
+ }
+};
+
/**
* nand_command - [DEFAULT] Send command to NAND device
* @mtd: MTD device structure
static void nand_command(struct mtd_info *mtd, unsigned int command,
int column, int page_addr)
{
- register struct nand_chip *chip = mtd->priv;
+ register struct nand_chip *chip = mtd_to_nand(mtd);
int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
- uint32_t rst_sts_cnt = CONFIG_SYS_NAND_RESET_CNT;
/* Write out the command to the device */
if (command == NAND_CMD_SEQIN) {
NAND_CTRL_CLE | NAND_CTRL_CHANGE);
chip->cmd_ctrl(mtd,
NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
- while (!(chip->read_byte(mtd) & NAND_STATUS_READY) &&
- (rst_sts_cnt--));
+ /* EZ-NAND can take upto 250ms as per ONFi v4.0 */
+ nand_wait_status_ready(mtd, 250);
return;
/* This applies to read commands */
static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
int column, int page_addr)
{
- register struct nand_chip *chip = mtd->priv;
- uint32_t rst_sts_cnt = CONFIG_SYS_NAND_RESET_CNT;
+ register struct nand_chip *chip = mtd_to_nand(mtd);
/* Emulate NAND_CMD_READOOB */
if (command == NAND_CMD_READOOB) {
/*
* Program and erase have their own busy handlers status, sequential
- * in, and deplete1 need no delay.
+ * in and status need no delay.
*/
switch (command) {
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
chip->cmd_ctrl(mtd, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
- while (!(chip->read_byte(mtd) & NAND_STATUS_READY) &&
- (rst_sts_cnt--));
+ /* EZ-NAND can take upto 250ms as per ONFi v4.0 */
+ nand_wait_status_ready(mtd, 250);
return;
case NAND_CMD_RNDOUT:
static int
nand_get_device(struct mtd_info *mtd, int new_state)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
chip->state = new_state;
return 0;
}
* @mtd: MTD device structure
* @chip: NAND chip structure
*
- * Wait for command done. This applies to erase and program only. Erase can
- * take up to 400ms and program up to 20ms according to general NAND and
- * SmartMedia specs.
+ * Wait for command done. This applies to erase and program only.
*/
static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
{
-
- int status, state = chip->state;
- unsigned long timeo = (state == FL_ERASING ? 400 : 20);
+ int status;
+ unsigned long timeo = 400;
led_trigger_event(nand_led_trigger, LED_FULL);
return status;
}
+#define BITS_PER_BYTE 8
+
+/**
+ * nand_check_erased_buf - check if a buffer contains (almost) only 0xff data
+ * @buf: buffer to test
+ * @len: buffer length
+ * @bitflips_threshold: maximum number of bitflips
+ *
+ * Check if a buffer contains only 0xff, which means the underlying region
+ * has been erased and is ready to be programmed.
+ * The bitflips_threshold specify the maximum number of bitflips before
+ * considering the region is not erased.
+ * Note: The logic of this function has been extracted from the memweight
+ * implementation, except that nand_check_erased_buf function exit before
+ * testing the whole buffer if the number of bitflips exceed the
+ * bitflips_threshold value.
+ *
+ * Returns a positive number of bitflips less than or equal to
+ * bitflips_threshold, or -ERROR_CODE for bitflips in excess of the
+ * threshold.
+ */
+static int nand_check_erased_buf(void *buf, int len, int bitflips_threshold)
+{
+ const unsigned char *bitmap = buf;
+ int bitflips = 0;
+ int weight;
+
+ for (; len && ((uintptr_t)bitmap) % sizeof(long);
+ len--, bitmap++) {
+ weight = hweight8(*bitmap);
+ bitflips += BITS_PER_BYTE - weight;
+ if (unlikely(bitflips > bitflips_threshold))
+ return -EBADMSG;
+ }
+
+ for (; len >= 4; len -= 4, bitmap += 4) {
+ weight = hweight32(*((u32 *)bitmap));
+ bitflips += 32 - weight;
+ if (unlikely(bitflips > bitflips_threshold))
+ return -EBADMSG;
+ }
+
+ for (; len > 0; len--, bitmap++) {
+ weight = hweight8(*bitmap);
+ bitflips += BITS_PER_BYTE - weight;
+ if (unlikely(bitflips > bitflips_threshold))
+ return -EBADMSG;
+ }
+
+ return bitflips;
+}
+
+/**
+ * nand_check_erased_ecc_chunk - check if an ECC chunk contains (almost) only
+ * 0xff data
+ * @data: data buffer to test
+ * @datalen: data length
+ * @ecc: ECC buffer
+ * @ecclen: ECC length
+ * @extraoob: extra OOB buffer
+ * @extraooblen: extra OOB length
+ * @bitflips_threshold: maximum number of bitflips
+ *
+ * Check if a data buffer and its associated ECC and OOB data contains only
+ * 0xff pattern, which means the underlying region has been erased and is
+ * ready to be programmed.
+ * The bitflips_threshold specify the maximum number of bitflips before
+ * considering the region as not erased.
+ *
+ * Note:
+ * 1/ ECC algorithms are working on pre-defined block sizes which are usually
+ * different from the NAND page size. When fixing bitflips, ECC engines will
+ * report the number of errors per chunk, and the NAND core infrastructure
+ * expect you to return the maximum number of bitflips for the whole page.
+ * This is why you should always use this function on a single chunk and
+ * not on the whole page. After checking each chunk you should update your
+ * max_bitflips value accordingly.
+ * 2/ When checking for bitflips in erased pages you should not only check
+ * the payload data but also their associated ECC data, because a user might
+ * have programmed almost all bits to 1 but a few. In this case, we
+ * shouldn't consider the chunk as erased, and checking ECC bytes prevent
+ * this case.
+ * 3/ The extraoob argument is optional, and should be used if some of your OOB
+ * data are protected by the ECC engine.
+ * It could also be used if you support subpages and want to attach some
+ * extra OOB data to an ECC chunk.
+ *
+ * Returns a positive number of bitflips less than or equal to
+ * bitflips_threshold, or -ERROR_CODE for bitflips in excess of the
+ * threshold. In case of success, the passed buffers are filled with 0xff.
+ */
+int nand_check_erased_ecc_chunk(void *data, int datalen,
+ void *ecc, int ecclen,
+ void *extraoob, int extraooblen,
+ int bitflips_threshold)
+{
+ int data_bitflips = 0, ecc_bitflips = 0, extraoob_bitflips = 0;
+
+ data_bitflips = nand_check_erased_buf(data, datalen,
+ bitflips_threshold);
+ if (data_bitflips < 0)
+ return data_bitflips;
+
+ bitflips_threshold -= data_bitflips;
+
+ ecc_bitflips = nand_check_erased_buf(ecc, ecclen, bitflips_threshold);
+ if (ecc_bitflips < 0)
+ return ecc_bitflips;
+
+ bitflips_threshold -= ecc_bitflips;
+
+ extraoob_bitflips = nand_check_erased_buf(extraoob, extraooblen,
+ bitflips_threshold);
+ if (extraoob_bitflips < 0)
+ return extraoob_bitflips;
+
+ if (data_bitflips)
+ memset(data, 0xff, datalen);
+
+ if (ecc_bitflips)
+ memset(ecc, 0xff, ecclen);
+
+ if (extraoob_bitflips)
+ memset(extraoob, 0xff, extraooblen);
+
+ return data_bitflips + ecc_bitflips + extraoob_bitflips;
+}
+EXPORT_SYMBOL(nand_check_erased_ecc_chunk);
+
/**
* nand_read_page_raw - [INTERN] read raw page data without ecc
* @mtd: mtd info structure
* ecc.pos. Let's make sure that there are no gaps in ECC positions.
*/
for (i = 0; i < eccfrag_len - 1; i++) {
- if (eccpos[i + start_step * chip->ecc.bytes] + 1 !=
- eccpos[i + start_step * chip->ecc.bytes + 1]) {
+ if (eccpos[i + index] + 1 != eccpos[i + index + 1]) {
gaps = 1;
break;
}
stat = chip->ecc.correct(mtd, p,
&chip->buffers->ecccode[i], &chip->buffers->ecccalc[i]);
+ if (stat == -EBADMSG &&
+ (chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
+ /* check for empty pages with bitflips */
+ stat = nand_check_erased_ecc_chunk(p, chip->ecc.size,
+ &chip->buffers->ecccode[i],
+ chip->ecc.bytes,
+ NULL, 0,
+ chip->ecc.strength);
+ }
+
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
int stat;
stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
+ if (stat == -EBADMSG &&
+ (chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
+ /* check for empty pages with bitflips */
+ stat = nand_check_erased_ecc_chunk(p, eccsize,
+ &ecc_code[i], eccbytes,
+ NULL, 0,
+ chip->ecc.strength);
+ }
+
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
chip->ecc.calculate(mtd, p, &ecc_calc[i]);
stat = chip->ecc.correct(mtd, p, &ecc_code[i], NULL);
+ if (stat == -EBADMSG &&
+ (chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
+ /* check for empty pages with bitflips */
+ stat = nand_check_erased_ecc_chunk(p, eccsize,
+ &ecc_code[i], eccbytes,
+ NULL, 0,
+ chip->ecc.strength);
+ }
+
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
+ int eccpadbytes = eccbytes + chip->ecc.prepad + chip->ecc.postpad;
uint8_t *p = buf;
uint8_t *oob = chip->oob_poi;
unsigned int max_bitflips = 0;
chip->read_buf(mtd, oob, eccbytes);
stat = chip->ecc.correct(mtd, p, oob, NULL);
- if (stat < 0) {
- mtd->ecc_stats.failed++;
- } else {
- mtd->ecc_stats.corrected += stat;
- max_bitflips = max_t(unsigned int, max_bitflips, stat);
- }
-
oob += eccbytes;
if (chip->ecc.postpad) {
chip->read_buf(mtd, oob, chip->ecc.postpad);
oob += chip->ecc.postpad;
}
+
+ if (stat == -EBADMSG &&
+ (chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
+ /* check for empty pages with bitflips */
+ stat = nand_check_erased_ecc_chunk(p, chip->ecc.size,
+ oob - eccpadbytes,
+ eccpadbytes,
+ NULL, 0,
+ chip->ecc.strength);
+ }
+
+ if (stat < 0) {
+ mtd->ecc_stats.failed++;
+ } else {
+ mtd->ecc_stats.corrected += stat;
+ max_bitflips = max_t(unsigned int, max_bitflips, stat);
+ }
}
/* Calculate remaining oob bytes */
*/
static int nand_setup_read_retry(struct mtd_info *mtd, int retry_mode)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
pr_debug("setting READ RETRY mode %d\n", retry_mode);
struct mtd_oob_ops *ops)
{
int chipnr, page, realpage, col, bytes, aligned, oob_required;
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
int ret = 0;
uint32_t readlen = ops->len;
uint32_t oobreadlen = ops->ooblen;
- uint32_t max_oobsize = ops->mode == MTD_OPS_AUTO_OOB ?
- mtd->oobavail : mtd->oobsize;
+ uint32_t max_oobsize = mtd_oobavail(mtd, ops);
uint8_t *bufpoi, *oob, *buf;
+ int use_bufpoi;
unsigned int max_bitflips = 0;
int retry_mode = 0;
bool ecc_fail = false;
bytes = min(mtd->writesize - col, readlen);
aligned = (bytes == mtd->writesize);
+ if (!aligned)
+ use_bufpoi = 1;
+ else
+ use_bufpoi = 0;
+
/* Is the current page in the buffer? */
if (realpage != chip->pagebuf || oob) {
- bufpoi = aligned ? buf : chip->buffers->databuf;
+ bufpoi = use_bufpoi ? chip->buffers->databuf : buf;
+
+ if (use_bufpoi && aligned)
+ pr_debug("%s: using read bounce buffer for buf@%p\n",
+ __func__, buf);
read_retry:
chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
ret = chip->ecc.read_page(mtd, chip, bufpoi,
oob_required, page);
if (ret < 0) {
- if (!aligned)
+ if (use_bufpoi)
/* Invalidate page cache */
chip->pagebuf = -1;
break;
max_bitflips = max_t(unsigned int, max_bitflips, ret);
/* Transfer not aligned data */
- if (!aligned) {
+ if (use_bufpoi) {
if (!NAND_HAS_SUBPAGE_READ(chip) && !oob &&
!(mtd->ecc_stats.failed - ecc_failures) &&
(ops->mode != MTD_OPS_RAW)) {
int ret;
nand_get_device(mtd, FL_READING);
+ memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = buf;
- ops.oobbuf = NULL;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_read_ops(mtd, from, &ops);
*retlen = ops.retlen;
static int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
int page)
{
- uint8_t *buf = chip->oob_poi;
int length = mtd->oobsize;
int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
int eccsize = chip->ecc.size;
- uint8_t *bufpoi = buf;
+ uint8_t *bufpoi = chip->oob_poi;
int i, toread, sndrnd = 0, pos;
chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
struct mtd_oob_ops *ops)
{
int page, realpage, chipnr;
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
struct mtd_ecc_stats stats;
int readlen = ops->ooblen;
int len;
stats = mtd->ecc_stats;
- if (ops->mode == MTD_OPS_AUTO_OOB)
- len = chip->ecc.layout->oobavail;
- else
- len = mtd->oobsize;
+ len = mtd_oobavail(mtd, ops);
if (unlikely(ops->ooboffs >= len)) {
pr_debug("%s: attempt to start read outside oob\n",
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
+ * @page: page number to write
*
* Not for syndrome calculating ECC controllers, which use a special oob layout.
*/
static int nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
- const uint8_t *buf, int oob_required)
+ const uint8_t *buf, int oob_required, int page)
{
chip->write_buf(mtd, buf, mtd->writesize);
if (oob_required)
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
+ * @page: page number to write
*
* We need a special oob layout and handling even when ECC isn't checked.
*/
static int nand_write_page_raw_syndrome(struct mtd_info *mtd,
struct nand_chip *chip,
- const uint8_t *buf, int oob_required)
+ const uint8_t *buf, int oob_required,
+ int page)
{
int eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
+ * @page: page number to write
*/
static int nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
- const uint8_t *buf, int oob_required)
+ const uint8_t *buf, int oob_required,
+ int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
for (i = 0; i < chip->ecc.total; i++)
chip->oob_poi[eccpos[i]] = ecc_calc[i];
- return chip->ecc.write_page_raw(mtd, chip, buf, 1);
+ return chip->ecc.write_page_raw(mtd, chip, buf, 1, page);
}
/**
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
+ * @page: page number to write
*/
static int nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
- const uint8_t *buf, int oob_required)
+ const uint8_t *buf, int oob_required,
+ int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
/**
- * nand_write_subpage_hwecc - [REPLACABLE] hardware ECC based subpage write
+ * nand_write_subpage_hwecc - [REPLACEABLE] hardware ECC based subpage write
* @mtd: mtd info structure
* @chip: nand chip info structure
* @offset: column address of subpage within the page
* @data_len: data length
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
+ * @page: page number to write
*/
static int nand_write_subpage_hwecc(struct mtd_info *mtd,
struct nand_chip *chip, uint32_t offset,
uint32_t data_len, const uint8_t *buf,
- int oob_required)
+ int oob_required, int page)
{
uint8_t *oob_buf = chip->oob_poi;
uint8_t *ecc_calc = chip->buffers->ecccalc;
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
+ * @page: page number to write
*
* The hw generator calculates the error syndrome automatically. Therefore we
* need a special oob layout and handling.
*/
static int nand_write_page_syndrome(struct mtd_info *mtd,
struct nand_chip *chip,
- const uint8_t *buf, int oob_required)
+ const uint8_t *buf, int oob_required,
+ int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
if (unlikely(raw))
status = chip->ecc.write_page_raw(mtd, chip, buf,
- oob_required);
+ oob_required, page);
else if (subpage)
status = chip->ecc.write_subpage(mtd, chip, offset, data_len,
- buf, oob_required);
+ buf, oob_required, page);
else
- status = chip->ecc.write_page(mtd, chip, buf, oob_required);
+ status = chip->ecc.write_page(mtd, chip, buf, oob_required,
+ page);
if (status < 0)
return status;
static uint8_t *nand_fill_oob(struct mtd_info *mtd, uint8_t *oob, size_t len,
struct mtd_oob_ops *ops)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
/*
* Initialise to all 0xFF, to avoid the possibility of left over OOB
struct mtd_oob_ops *ops)
{
int chipnr, realpage, page, blockmask, column;
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
uint32_t writelen = ops->len;
uint32_t oobwritelen = ops->ooblen;
- uint32_t oobmaxlen = ops->mode == MTD_OPS_AUTO_OOB ?
- mtd->oobavail : mtd->oobsize;
+ uint32_t oobmaxlen = mtd_oobavail(mtd, ops);
uint8_t *oob = ops->oobbuf;
uint8_t *buf = ops->datbuf;
blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
/* Invalidate the page cache, when we write to the cached page */
- if (to <= (chip->pagebuf << chip->page_shift) &&
- (chip->pagebuf << chip->page_shift) < (to + ops->len))
+ if (to <= ((loff_t)chip->pagebuf << chip->page_shift) &&
+ ((loff_t)chip->pagebuf << chip->page_shift) < (to + ops->len))
chip->pagebuf = -1;
/* Don't allow multipage oob writes with offset */
int bytes = mtd->writesize;
int cached = writelen > bytes && page != blockmask;
uint8_t *wbuf = buf;
+ int use_bufpoi;
+ int part_pagewr = (column || writelen < mtd->writesize);
+
+ if (part_pagewr)
+ use_bufpoi = 1;
+ else
+ use_bufpoi = 0;
WATCHDOG_RESET();
- /* Partial page write? */
- if (unlikely(column || writelen < (mtd->writesize - 1))) {
+ /* Partial page write?, or need to use bounce buffer */
+ if (use_bufpoi) {
+ pr_debug("%s: using write bounce buffer for buf@%p\n",
+ __func__, buf);
cached = 0;
- bytes = min_t(int, bytes - column, (int) writelen);
+ if (part_pagewr)
+ bytes = min_t(int, bytes - column, writelen);
chip->pagebuf = -1;
memset(chip->buffers->databuf, 0xff, mtd->writesize);
memcpy(&chip->buffers->databuf[column], buf, bytes);
static int panic_nand_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const uint8_t *buf)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
struct mtd_oob_ops ops;
int ret;
/* Grab the device */
panic_nand_get_device(chip, mtd, FL_WRITING);
+ memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = (uint8_t *)buf;
- ops.oobbuf = NULL;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_write_ops(mtd, to, &ops);
int ret;
nand_get_device(mtd, FL_WRITING);
+ memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = (uint8_t *)buf;
- ops.oobbuf = NULL;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_write_ops(mtd, to, &ops);
*retlen = ops.retlen;
struct mtd_oob_ops *ops)
{
int chipnr, page, status, len;
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
pr_debug("%s: to = 0x%08x, len = %i\n",
__func__, (unsigned int)to, (int)ops->ooblen);
- if (ops->mode == MTD_OPS_AUTO_OOB)
- len = chip->ecc.layout->oobavail;
- else
- len = mtd->oobsize;
+ len = mtd_oobavail(mtd, ops);
/* Do not allow write past end of page */
if ((ops->ooboffs + ops->ooblen) > len) {
}
/**
- * single_erase_cmd - [GENERIC] NAND standard block erase command function
+ * single_erase - [GENERIC] NAND standard block erase command function
* @mtd: MTD device structure
* @page: the page address of the block which will be erased
*
- * Standard erase command for NAND chips.
+ * Standard erase command for NAND chips. Returns NAND status.
*/
-static void single_erase_cmd(struct mtd_info *mtd, int page)
+static int single_erase(struct mtd_info *mtd, int page)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
/* Send commands to erase a block */
chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
+
+ return chip->waitfunc(mtd, chip);
}
/**
int allowbbt)
{
int page, status, pages_per_block, ret, chipnr;
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
loff_t len;
pr_debug("%s: start = 0x%012llx, len = %llu\n",
/* Check if we have a bad block, we do not erase bad blocks! */
if (!instr->scrub && nand_block_checkbad(mtd, ((loff_t) page) <<
- chip->page_shift, 0, allowbbt)) {
+ chip->page_shift, allowbbt)) {
pr_warn("%s: attempt to erase a bad block at page 0x%08x\n",
__func__, page);
instr->state = MTD_ERASE_FAILED;
(page + pages_per_block))
chip->pagebuf = -1;
- chip->erase_cmd(mtd, page & chip->pagemask);
-
- status = chip->waitfunc(mtd, chip);
+ status = chip->erase(mtd, page & chip->pagemask);
/*
* See if operation failed and additional status checks are
*/
static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
{
- return nand_block_checkbad(mtd, offs, 1, 0);
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int chipnr = (int)(offs >> chip->chip_shift);
+ int ret;
+
+ /* Select the NAND device */
+ nand_get_device(mtd, FL_READING);
+ chip->select_chip(mtd, chipnr);
+
+ ret = nand_block_checkbad(mtd, offs, 0);
+
+ chip->select_chip(mtd, -1);
+ nand_release_device(mtd);
+
+ return ret;
}
/**
return -EINVAL;
#endif
- /* clear the sub feature parameters */
- memset(subfeature_param, 0, ONFI_SUBFEATURE_PARAM_LEN);
-
chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES, addr, -1);
for (i = 0; i < ONFI_SUBFEATURE_PARAM_LEN; ++i)
*subfeature_param++ = chip->read_byte(mtd);
return 0;
}
-
/* Set default functions */
static void nand_set_defaults(struct nand_chip *chip, int busw)
{
static int nand_setup_read_retry_micron(struct mtd_info *mtd, int retry_mode)
{
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
uint8_t feature[ONFI_SUBFEATURE_PARAM_LEN] = {retry_mode};
return chip->onfi_set_features(mtd, chip, ONFI_FEATURE_ADDR_READ_RETRY,
chip->options |= type->options;
chip->ecc_strength_ds = NAND_ECC_STRENGTH(type);
chip->ecc_step_ds = NAND_ECC_STEP(type);
+ chip->onfi_timing_mode_default =
+ type->onfi_timing_mode_default;
*busw = type->options & NAND_BUSWIDTH_16;
if (find_full_id_nand(mtd, chip, type, id_data, &busw))
goto ident_done;
} else if (*dev_id == type->dev_id) {
- break;
+ break;
}
}
chip->onfi_version = 0;
if (!type->name || !type->pagesize) {
- /* Check is chip is ONFI compliant */
+ /* Check if the chip is ONFI compliant */
if (nand_flash_detect_onfi(mtd, chip, &busw))
goto ident_done;
chip->chipsize = (uint64_t)type->chipsize << 20;
- if (!type->pagesize && chip->init_size) {
- /* Set the pagesize, oobsize, erasesize by the driver */
- busw = chip->init_size(mtd, chip, id_data);
- } else if (!type->pagesize) {
+ if (!type->pagesize) {
/* Decode parameters from extended ID */
nand_decode_ext_id(mtd, chip, id_data, &busw);
} else {
}
chip->badblockbits = 8;
- chip->erase_cmd = single_erase_cmd;
+ chip->erase = single_erase;
/* Do not replace user supplied command function! */
if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
type->name);
#endif
- pr_info("%dMiB, %s, page size: %d, OOB size: %d\n",
+ pr_info("%d MiB, %s, erase size: %d KiB, page size: %d, OOB size: %d\n",
(int)(chip->chipsize >> 20), nand_is_slc(chip) ? "SLC" : "MLC",
- mtd->writesize, mtd->oobsize);
+ mtd->erasesize >> 10, mtd->writesize, mtd->oobsize);
return type;
}
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+DECLARE_GLOBAL_DATA_PTR;
+
+static int nand_dt_init(struct mtd_info *mtd, struct nand_chip *chip, int node)
+{
+ int ret, ecc_mode = -1, ecc_strength, ecc_step;
+ const void *blob = gd->fdt_blob;
+ const char *str;
+
+ ret = fdtdec_get_int(blob, node, "nand-bus-width", -1);
+ if (ret == 16)
+ chip->options |= NAND_BUSWIDTH_16;
+
+ if (fdtdec_get_bool(blob, node, "nand-on-flash-bbt"))
+ chip->bbt_options |= NAND_BBT_USE_FLASH;
+
+ str = fdt_getprop(blob, node, "nand-ecc-mode", NULL);
+ if (str) {
+ if (!strcmp(str, "none"))
+ ecc_mode = NAND_ECC_NONE;
+ else if (!strcmp(str, "soft"))
+ ecc_mode = NAND_ECC_SOFT;
+ else if (!strcmp(str, "hw"))
+ ecc_mode = NAND_ECC_HW;
+ else if (!strcmp(str, "hw_syndrome"))
+ ecc_mode = NAND_ECC_HW_SYNDROME;
+ else if (!strcmp(str, "hw_oob_first"))
+ ecc_mode = NAND_ECC_HW_OOB_FIRST;
+ else if (!strcmp(str, "soft_bch"))
+ ecc_mode = NAND_ECC_SOFT_BCH;
+ }
+
+
+ ecc_strength = fdtdec_get_int(blob, node, "nand-ecc-strength", -1);
+ ecc_step = fdtdec_get_int(blob, node, "nand-ecc-step-size", -1);
+
+ if ((ecc_step >= 0 && !(ecc_strength >= 0)) ||
+ (!(ecc_step >= 0) && ecc_strength >= 0)) {
+ pr_err("must set both strength and step size in DT\n");
+ return -EINVAL;
+ }
+
+ if (ecc_mode >= 0)
+ chip->ecc.mode = ecc_mode;
+
+ if (ecc_strength >= 0)
+ chip->ecc.strength = ecc_strength;
+
+ if (ecc_step > 0)
+ chip->ecc.size = ecc_step;
+
+ return 0;
+}
+#else
+static int nand_dt_init(struct mtd_info *mtd, struct nand_chip *chip, int node)
+{
+ return 0;
+}
+#endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
+
/**
* nand_scan_ident - [NAND Interface] Scan for the NAND device
* @mtd: MTD device structure
* This is the first phase of the normal nand_scan() function. It reads the
* flash ID and sets up MTD fields accordingly.
*
- * The mtd->owner field must be set to the module of the caller.
*/
int nand_scan_ident(struct mtd_info *mtd, int maxchips,
struct nand_flash_dev *table)
{
int i, nand_maf_id, nand_dev_id;
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_flash_dev *type;
+ int ret;
+
+ if (chip->flash_node) {
+ ret = nand_dt_init(mtd, chip, chip->flash_node);
+ if (ret)
+ return ret;
+ }
/* Set the default functions */
nand_set_defaults(chip, chip->options & NAND_BUSWIDTH_16);
}
EXPORT_SYMBOL(nand_scan_ident);
+/*
+ * Check if the chip configuration meet the datasheet requirements.
+
+ * If our configuration corrects A bits per B bytes and the minimum
+ * required correction level is X bits per Y bytes, then we must ensure
+ * both of the following are true:
+ *
+ * (1) A / B >= X / Y
+ * (2) A >= X
+ *
+ * Requirement (1) ensures we can correct for the required bitflip density.
+ * Requirement (2) ensures we can correct even when all bitflips are clumped
+ * in the same sector.
+ */
+static bool nand_ecc_strength_good(struct mtd_info *mtd)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int corr, ds_corr;
+
+ if (ecc->size == 0 || chip->ecc_step_ds == 0)
+ /* Not enough information */
+ return true;
+
+ /*
+ * We get the number of corrected bits per page to compare
+ * the correction density.
+ */
+ corr = (mtd->writesize * ecc->strength) / ecc->size;
+ ds_corr = (mtd->writesize * chip->ecc_strength_ds) / chip->ecc_step_ds;
+
+ return corr >= ds_corr && ecc->strength >= chip->ecc_strength_ds;
+}
/**
* nand_scan_tail - [NAND Interface] Scan for the NAND device
int nand_scan_tail(struct mtd_info *mtd)
{
int i;
- struct nand_chip *chip = mtd->priv;
+ struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
struct nand_buffers *nbuf;
case NAND_ECC_HW_OOB_FIRST:
/* Similar to NAND_ECC_HW, but a separate read_page handle */
if (!ecc->calculate || !ecc->correct || !ecc->hwctl) {
- pr_warn("No ECC functions supplied; "
- "hardware ECC not possible\n");
+ pr_warn("No ECC functions supplied; hardware ECC not possible\n");
BUG();
}
if (!ecc->read_page)
ecc->write_oob = nand_write_oob_std;
if (!ecc->read_subpage)
ecc->read_subpage = nand_read_subpage;
- if (!ecc->write_subpage)
+ if (!ecc->write_subpage && ecc->hwctl && ecc->calculate)
ecc->write_subpage = nand_write_subpage_hwecc;
case NAND_ECC_HW_SYNDROME:
ecc->read_page == nand_read_page_hwecc ||
!ecc->write_page ||
ecc->write_page == nand_write_page_hwecc)) {
- pr_warn("No ECC functions supplied; "
- "hardware ECC not possible\n");
+ pr_warn("No ECC functions supplied; hardware ECC not possible\n");
BUG();
}
/* Use standard syndrome read/write page function? */
}
break;
}
- pr_warn("%d byte HW ECC not possible on "
- "%d byte page size, fallback to SW ECC\n",
- ecc->size, mtd->writesize);
+ pr_warn("%d byte HW ECC not possible on %d byte page size, fallback to SW ECC\n",
+ ecc->size, mtd->writesize);
ecc->mode = NAND_ECC_SOFT;
case NAND_ECC_SOFT:
ecc->read_oob = nand_read_oob_std;
ecc->write_oob = nand_write_oob_std;
/*
- * Board driver should supply ecc.size and ecc.bytes values to
- * select how many bits are correctable; see nand_bch_init()
- * for details. Otherwise, default to 4 bits for large page
- * devices.
+ * Board driver should supply ecc.size and ecc.strength values
+ * to select how many bits are correctable. Otherwise, default
+ * to 4 bits for large page devices.
*/
if (!ecc->size && (mtd->oobsize >= 64)) {
ecc->size = 512;
- ecc->bytes = 7;
+ ecc->strength = 4;
}
- ecc->priv = nand_bch_init(mtd, ecc->size, ecc->bytes,
- &ecc->layout);
+
+ /* See nand_bch_init() for details. */
+ ecc->bytes = 0;
+ ecc->priv = nand_bch_init(mtd);
if (!ecc->priv) {
pr_warn("BCH ECC initialization failed!\n");
BUG();
}
- ecc->strength = ecc->bytes * 8 / fls(8 * ecc->size);
break;
case NAND_ECC_NONE:
- pr_warn("NAND_ECC_NONE selected by board driver. "
- "This is not recommended!\n");
+ pr_warn("NAND_ECC_NONE selected by board driver. This is not recommended!\n");
ecc->read_page = nand_read_page_raw;
ecc->write_page = nand_write_page_raw;
ecc->read_oob = nand_read_oob_std;
* The number of bytes available for a client to place data into
* the out of band area.
*/
- ecc->layout->oobavail = 0;
- for (i = 0; ecc->layout->oobfree[i].length
- && i < ARRAY_SIZE(ecc->layout->oobfree); i++)
- ecc->layout->oobavail += ecc->layout->oobfree[i].length;
- mtd->oobavail = ecc->layout->oobavail;
+ mtd->oobavail = 0;
+ if (ecc->layout) {
+ for (i = 0; ecc->layout->oobfree[i].length; i++)
+ mtd->oobavail += ecc->layout->oobfree[i].length;
+ }
+
+ /* ECC sanity check: warn if it's too weak */
+ if (!nand_ecc_strength_good(mtd))
+ pr_warn("WARNING: %s: the ECC used on your system is too weak compared to the one required by the NAND chip\n",
+ mtd->name);
/*
* Set the number of read / write steps for one page depending on ECC
chip->pagebuf = -1;
/* Large page NAND with SOFT_ECC should support subpage reads */
- if ((ecc->mode == NAND_ECC_SOFT) && (chip->page_shift > 9))
- chip->options |= NAND_SUBPAGE_READ;
+ switch (ecc->mode) {
+ case NAND_ECC_SOFT:
+ case NAND_ECC_SOFT_BCH:
+ if (chip->page_shift > 9)
+ chip->options |= NAND_SUBPAGE_READ;
+ break;
+
+ default:
+ break;
+ }
/* Fill in remaining MTD driver data */
mtd->type = nand_is_slc(chip) ? MTD_NANDFLASH : MTD_MLCNANDFLASH;
mtd->_sync = nand_sync;
mtd->_lock = NULL;
mtd->_unlock = NULL;
+ mtd->_block_isreserved = nand_block_isreserved;
mtd->_block_isbad = nand_block_isbad;
mtd->_block_markbad = nand_block_markbad;
mtd->writebufsize = mtd->writesize;
* properly set.
*/
if (!mtd->bitflip_threshold)
- mtd->bitflip_threshold = mtd->ecc_strength;
+ mtd->bitflip_threshold = DIV_ROUND_UP(mtd->ecc_strength * 3, 4);
return 0;
}
EXPORT_SYMBOL(nand_scan_tail);
-/*
- * is_module_text_address() isn't exported, and it's mostly a pointless
- * test if this is a module _anyway_ -- they'd have to try _really_ hard
- * to call us from in-kernel code if the core NAND support is modular.
- */
-#ifdef MODULE
-#define caller_is_module() (1)
-#else
-#define caller_is_module() \
- is_module_text_address((unsigned long)__builtin_return_address(0))
-#endif
-
/**
* nand_scan - [NAND Interface] Scan for the NAND device
* @mtd: MTD device structure
*
* This fills out all the uninitialized function pointers with the defaults.
* The flash ID is read and the mtd/chip structures are filled with the
- * appropriate values. The mtd->owner field must be set to the module of the
- * caller.
+ * appropriate values.
*/
int nand_scan(struct mtd_info *mtd, int maxchips)
{
int ret;
- /* Many callers got this wrong, so check for it for a while... */
- if (!mtd->owner && caller_is_module()) {
- pr_crit("%s called with NULL mtd->owner!\n", __func__);
- BUG();
- }
-
ret = nand_scan_ident(mtd, maxchips, NULL);
if (!ret)
ret = nand_scan_tail(mtd);
}
EXPORT_SYMBOL(nand_scan);
-module_init(nand_base_init);
-module_exit(nand_base_exit);
-
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>");
MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");