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authorKyungmin Park <kmpark@infradead.org>2008-11-17 17:54:28 +0900
committerDavid Woodhouse <David.Woodhouse@intel.com>2009-03-23 15:14:46 +0000
commit9ce969082e490d0a5a81862b364337c93dc3482a (patch)
treed5cec57f918b38062496162f362e727a6da0043e /drivers/mtd/onenand
parenta29f280b739985a9e829d67af4d08e6584153495 (diff)
[MTD] [OneNAND] Add write-while-program support
OneNAND write-while-program method of writing improves performance, compared with ordinary writes, by transferring data to OneNAND's RAM buffers atthe same time as programming the NAND core. When writing several NAND pages at a time, an improvement of 12% to 25% is seen. Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/mtd/onenand')
-rw-r--r--drivers/mtd/onenand/onenand_base.c145
1 files changed, 96 insertions, 49 deletions
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 529af271db1..30d6999e5f9 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -1455,7 +1455,8 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops)
{
struct onenand_chip *this = mtd->priv;
- int written = 0, column, thislen, subpage;
+ int written = 0, column, thislen = 0, subpage = 0;
+ int prev = 0, prevlen = 0, prev_subpage = 0, first = 1;
int oobwritten = 0, oobcolumn, thisooblen, oobsize;
size_t len = ops->len;
size_t ooblen = ops->ooblen;
@@ -1482,6 +1483,10 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
return -EINVAL;
}
+ /* Check zero length */
+ if (!len)
+ return 0;
+
if (ops->mode == MTD_OOB_AUTO)
oobsize = this->ecclayout->oobavail;
else
@@ -1492,79 +1497,121 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
column = to & (mtd->writesize - 1);
/* Loop until all data write */
- while (written < len) {
- u_char *wbuf = (u_char *) buf;
+ while (1) {
+ if (written < len) {
+ u_char *wbuf = (u_char *) buf;
- thislen = min_t(int, mtd->writesize - column, len - written);
- thisooblen = min_t(int, oobsize - oobcolumn, ooblen - oobwritten);
+ thislen = min_t(int, mtd->writesize - column, len - written);
+ thisooblen = min_t(int, oobsize - oobcolumn, ooblen - oobwritten);
- cond_resched();
+ cond_resched();
- this->command(mtd, ONENAND_CMD_BUFFERRAM, to, thislen);
+ this->command(mtd, ONENAND_CMD_BUFFERRAM, to, thislen);
- /* Partial page write */
- subpage = thislen < mtd->writesize;
- if (subpage) {
- memset(this->page_buf, 0xff, mtd->writesize);
- memcpy(this->page_buf + column, buf, thislen);
- wbuf = this->page_buf;
- }
+ /* Partial page write */
+ subpage = thislen < mtd->writesize;
+ if (subpage) {
+ memset(this->page_buf, 0xff, mtd->writesize);
+ memcpy(this->page_buf + column, buf, thislen);
+ wbuf = this->page_buf;
+ }
- this->write_bufferram(mtd, ONENAND_DATARAM, wbuf, 0, mtd->writesize);
+ this->write_bufferram(mtd, ONENAND_DATARAM, wbuf, 0, mtd->writesize);
- if (oob) {
- oobbuf = this->oob_buf;
+ if (oob) {
+ oobbuf = this->oob_buf;
- /* We send data to spare ram with oobsize
- * to prevent byte access */
- memset(oobbuf, 0xff, mtd->oobsize);
- if (ops->mode == MTD_OOB_AUTO)
- onenand_fill_auto_oob(mtd, oobbuf, oob, oobcolumn, thisooblen);
- else
- memcpy(oobbuf + oobcolumn, oob, thisooblen);
+ /* We send data to spare ram with oobsize
+ * to prevent byte access */
+ memset(oobbuf, 0xff, mtd->oobsize);
+ if (ops->mode == MTD_OOB_AUTO)
+ onenand_fill_auto_oob(mtd, oobbuf, oob, oobcolumn, thisooblen);
+ else
+ memcpy(oobbuf + oobcolumn, oob, thisooblen);
- oobwritten += thisooblen;
- oob += thisooblen;
- oobcolumn = 0;
+ oobwritten += thisooblen;
+ oob += thisooblen;
+ oobcolumn = 0;
+ } else
+ oobbuf = (u_char *) ffchars;
+
+ this->write_bufferram(mtd, ONENAND_SPARERAM, oobbuf, 0, mtd->oobsize);
} else
- oobbuf = (u_char *) ffchars;
+ ONENAND_SET_NEXT_BUFFERRAM(this);
- this->write_bufferram(mtd, ONENAND_SPARERAM, oobbuf, 0, mtd->oobsize);
+ /*
+ * 2 PLANE, MLC, and Flex-OneNAND doesn't support
+ * write-while-programe feature.
+ */
+ if (!ONENAND_IS_2PLANE(this) && !first) {
+ ONENAND_SET_PREV_BUFFERRAM(this);
- this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
+ ret = this->wait(mtd, FL_WRITING);
- ret = this->wait(mtd, FL_WRITING);
+ /* In partial page write we don't update bufferram */
+ onenand_update_bufferram(mtd, prev, !ret && !prev_subpage);
+ if (ret) {
+ written -= prevlen;
+ printk(KERN_ERR "onenand_write_ops_nolock: write filaed %d\n", ret);
+ break;
+ }
- /* In partial page write we don't update bufferram */
- onenand_update_bufferram(mtd, to, !ret && !subpage);
- if (ONENAND_IS_2PLANE(this)) {
- ONENAND_SET_BUFFERRAM1(this);
- onenand_update_bufferram(mtd, to + this->writesize, !ret && !subpage);
- }
+ if (written == len) {
+ /* Only check verify write turn on */
+ ret = onenand_verify(mtd, buf - len, to - len, len);
+ if (ret)
+ printk(KERN_ERR "onenand_write_ops_nolock: verify failed %d\n", ret);
+ break;
+ }
- if (ret) {
- printk(KERN_ERR "onenand_write_ops_nolock: write filaed %d\n", ret);
- break;
+ ONENAND_SET_NEXT_BUFFERRAM(this);
}
- /* Only check verify write turn on */
- ret = onenand_verify(mtd, buf, to, thislen);
- if (ret) {
- printk(KERN_ERR "onenand_write_ops_nolock: verify failed %d\n", ret);
- break;
- }
+ this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
- written += thislen;
+ /*
+ * 2 PLANE, MLC, and Flex-OneNAND wait here
+ */
+ if (ONENAND_IS_2PLANE(this)) {
+ ret = this->wait(mtd, FL_WRITING);
- if (written == len)
- break;
+ /* In partial page write we don't update bufferram */
+ onenand_update_bufferram(mtd, to, !ret && !subpage);
+ if (ret) {
+ printk(KERN_ERR "onenand_write_ops_nolock: write filaed %d\n", ret);
+ break;
+ }
+
+ /* Only check verify write turn on */
+ ret = onenand_verify(mtd, buf, to, thislen);
+ if (ret) {
+ printk(KERN_ERR "onenand_write_ops_nolock: verify failed %d\n", ret);
+ break;
+ }
+
+ written += thislen;
+
+ if (written == len)
+ break;
+
+ } else
+ written += thislen;
column = 0;
+ prev_subpage = subpage;
+ prev = to;
+ prevlen = thislen;
to += thislen;
buf += thislen;
+ first = 0;
}
+ /* In error case, clear all bufferrams */
+ if (written != len)
+ onenand_invalidate_bufferram(mtd, 0, -1);
+
ops->retlen = written;
+ ops->oobretlen = oobwritten;
return ret;
}