[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>
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 529af27..30d6999 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -1455,7 +1455,8 @@
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 @@
return -EINVAL;
}
+ /* Check zero length */
+ if (!len)
+ return 0;
+
if (ops->mode == MTD_OOB_AUTO)
oobsize = this->ecclayout->oobavail;
else
@@ -1492,79 +1497,121 @@
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);
+
+ 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;
+ }
+
+ 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;
+ }
+
+ ONENAND_SET_NEXT_BUFFERRAM(this);
+ }
this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
- ret = this->wait(mtd, FL_WRITING);
-
- /* In partial page write we don't update bufferram */
- onenand_update_bufferram(mtd, to, !ret && !subpage);
+ /*
+ * 2 PLANE, MLC, and Flex-OneNAND wait here
+ */
if (ONENAND_IS_2PLANE(this)) {
- ONENAND_SET_BUFFERRAM1(this);
- onenand_update_bufferram(mtd, to + this->writesize, !ret && !subpage);
- }
+ ret = this->wait(mtd, FL_WRITING);
- if (ret) {
- 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 (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;
- }
+ /* 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;
+ written += thislen;
- if (written == len)
- break;
+ 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;
}