nand: Sync with Linux v4.1
Update the NAND code to match Linux v4.1. The previous sync was
from Linux v3.15 in commit 4e67c57125290b25.
CONFIG_SYS_NAND_RESET_CNT is removed, as the upstream Linux code now
has its own timeout. Plus, CONFIG_SYS_NAND_RESET_CNT was undocumented
and not selected by any board.
Signed-off-by: Scott Wood <scottwood@freescale.com>
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index bf4caa8..9e8fc1f 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -45,17 +45,6 @@
#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;}
/* Define default oob placement schemes for large and small page devices */
@@ -162,7 +151,6 @@
/**
* 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
*
* Default read function for 16bit buswidth with endianness conversion.
@@ -427,7 +415,7 @@
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) {
@@ -525,11 +513,11 @@
}
/**
- * nand_block_checkbad - [GENERIC] Check if a block is marked bad
+ * 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 mark as reserved.
+ * Check if the block is marked as reserved.
*/
static int nand_block_isreserved(struct mtd_info *mtd, loff_t ofs)
{
@@ -587,6 +575,27 @@
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->priv;
+ 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
* @command: the command to be sent
@@ -601,7 +610,6 @@
{
register struct nand_chip *chip = mtd->priv;
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) {
@@ -665,8 +673,8 @@
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 */
@@ -704,7 +712,6 @@
int column, int page_addr)
{
register struct nand_chip *chip = mtd->priv;
- uint32_t rst_sts_cnt = CONFIG_SYS_NAND_RESET_CNT;
/* Emulate NAND_CMD_READOOB */
if (command == NAND_CMD_READOOB) {
@@ -742,7 +749,7 @@
/*
* Program and erase have their own busy handlers status, sequential
- * in, and deplete1 need no delay.
+ * in and status need no delay.
*/
switch (command) {
@@ -763,8 +770,8 @@
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:
@@ -1062,8 +1069,7 @@
* 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;
}
@@ -1359,6 +1365,7 @@
mtd->oobavail : mtd->oobsize;
uint8_t *bufpoi, *oob, *buf;
+ int use_bufpoi;
unsigned int max_bitflips = 0;
int retry_mode = 0;
bool ecc_fail = false;
@@ -1382,9 +1389,18 @@
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);
@@ -1406,7 +1422,7 @@
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;
@@ -1415,7 +1431,7 @@
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)) {
@@ -1529,9 +1545,9 @@
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;
@@ -1563,11 +1579,10 @@
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);
@@ -1940,7 +1955,7 @@
/**
- * 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
@@ -2223,8 +2238,8 @@
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 */
@@ -2237,12 +2252,22 @@
int bytes = mtd->writesize;
int cached = writelen > bytes && page != blockmask;
uint8_t *wbuf = buf;
+ int use_bufpoi;
+ int part_pagewr = (column || writelen < (mtd->writesize - 1));
+
+ 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);
@@ -2313,9 +2338,9 @@
/* 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);
@@ -2341,9 +2366,9 @@
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;
@@ -2480,18 +2505,20 @@
}
/**
- * 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;
/* 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);
}
/**
@@ -2574,9 +2601,7 @@
(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
@@ -2729,7 +2754,6 @@
return 0;
}
-
/* Set default functions */
static void nand_set_defaults(struct nand_chip *chip, int busw)
{
@@ -3388,6 +3412,8 @@
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;
@@ -3460,7 +3486,7 @@
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;
@@ -3538,7 +3564,7 @@
}
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)
@@ -3569,9 +3595,9 @@
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;
}
@@ -3638,6 +3664,39 @@
}
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->priv;
+ 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
@@ -3705,8 +3764,7 @@
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)
@@ -3737,8 +3795,7 @@
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? */
@@ -3762,9 +3819,8 @@
}
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:
@@ -3798,27 +3854,28 @@
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;
}
+
+ /* See nand_bch_init() for details. */
+ ecc->bytes = DIV_ROUND_UP(
+ ecc->strength * fls(8 * ecc->size), 8);
ecc->priv = nand_bch_init(mtd, ecc->size, ecc->bytes,
&ecc->layout);
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;
@@ -3851,6 +3908,11 @@
ecc->layout->oobavail += ecc->layout->oobfree[i].length;
mtd->oobavail = ecc->layout->oobavail;
+ /* 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
* mode.
@@ -3884,8 +3946,16 @@
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;
@@ -3915,7 +3985,7 @@
* 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;
}