[RFC] [PATCH] [MTD] [OneNAND] Add write-while-program operation
Adrian Hunter
ext-adrian.hunter at nokia.com
Thu Aug 14 10:15:53 EDT 2008
Signed-off-by: Adrian Hunter <ext-adrian.hunter at nokia.com>
---
drivers/mtd/onenand/omap2.c | 2 +
drivers/mtd/onenand/onenand_base.c | 104 ++++++++++++++++++++++++++++++++++++
include/linux/mtd/onenand.h | 4 ++
3 files changed, 110 insertions(+), 0 deletions(-)
diff --git a/drivers/mtd/onenand/omap2.c b/drivers/mtd/onenand/omap2.c
index bf6bba5..236a68c 100644
--- a/drivers/mtd/onenand/omap2.c
+++ b/drivers/mtd/onenand/omap2.c
@@ -674,6 +674,8 @@ static int __devinit omap2_onenand_probe(struct platform_device *pdev)
if ((r = onenand_scan(&c->mtd, 1)) < 0)
goto err_release_dma;
+ c->mtd.write = onenand_write_while_prog;
+
switch ((c->onenand.version_id >> 4) & 0xf) {
case 0:
c->freq = 40;
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 5d7965f..ce10362 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -1573,6 +1573,110 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
return ret;
}
+/**
+ * onenand_write_while_prog - [MTD Interface] write while program
+ * @param mtd MTD device structure
+ * @param to offset to write to
+ * @param len number of bytes to write
+ * @param retlen pointer to variable to store the number of written bytes
+ * @param buf the data to write
+ *
+ * Write while program.
+ */
+int onenand_write_while_prog(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf)
+{
+ struct onenand_chip *this = mtd->priv;
+ int written = 0, column, uninitialized_var(thislen), uninitialized_var(lastlen);
+ int ret = 0, first_time = 1, uninitialized_var(subpage), uninitialized_var(prev_subpage);
+ loff_t prev = to;
+
+ onenand_get_device(mtd, FL_WRITING);
+
+ DEBUG(MTD_DEBUG_LEVEL3, "onenand_write_while_prog: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);
+
+ /* Initialize retlen, in case of early exit */
+ *retlen = 0;
+
+ /* Do not allow writes past end of device */
+ if (unlikely((to + len) > mtd->size)) {
+ printk(KERN_ERR "onenand_write_while_prog: Attempt write to past end of device\n");
+ onenand_release_device(mtd);
+ return -EINVAL;
+ }
+
+ /* Reject writes, which are not page aligned */
+ if (unlikely(NOTALIGNED(to)) || unlikely(NOTALIGNED(len))) {
+ printk(KERN_ERR "onenand_write_while_prog: Attempt to write not page aligned data\n");
+ onenand_release_device(mtd);
+ return -EINVAL;
+ }
+
+ if (!len) {
+ onenand_release_device(mtd);
+ return 0;
+ }
+
+ column = to & (mtd->writesize - 1);
+
+ /* Loop until all data is written */
+ while (1) {
+ if (written < len) {
+ u_char *wbuf = (u_char *)buf;
+
+ thislen = min_t(int, mtd->writesize - column, len - written);
+
+ cond_resched();
+
+ this->command(mtd, ONENAND_CMD_BUFFERRAM, to, thislen);
+
+ 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_SPARERAM, ffchars, 0, mtd->oobsize);
+ } else
+ ONENAND_SET_NEXT_BUFFERRAM(this);
+
+ if (!first_time) {
+ ONENAND_SET_PREV_BUFFERRAM(this);
+ ret = this->wait(mtd, FL_WRITING);
+ onenand_update_bufferram(mtd, prev, !ret && !prev_subpage);
+ if (ret) {
+ written -= lastlen;
+ printk(KERN_ERR "onenand_write_while_prog: write failed %d\n", ret);
+ break;
+ }
+ if (written == len) {
+ ret = onenand_verify(mtd, buf - len, to - len, len);
+ if (ret)
+ printk(KERN_ERR "onenand_write_while_prog: verify failed %d\n", ret);
+ break;
+ }
+ ONENAND_SET_NEXT_BUFFERRAM(this);
+ }
+
+ this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
+
+ written += thislen;
+ column = 0;
+ prev_subpage = subpage;
+ prev = to;
+ to += thislen;
+ buf += thislen;
+ lastlen = thislen;
+ first_time = 0;
+ }
+
+ *retlen = written;
+
+ onenand_release_device(mtd);
+ return ret;
+}
/**
* onenand_write_oob_nolock - [Internal] OneNAND write out-of-band
diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h
index 9aa2a91..1223430 100644
--- a/include/linux/mtd/onenand.h
+++ b/include/linux/mtd/onenand.h
@@ -24,6 +24,10 @@ extern int onenand_scan(struct mtd_info *mtd, int max_chips);
/* Free resources held by the OneNAND device */
extern void onenand_release(struct mtd_info *mtd);
+/* Alternative write algorithm : write-while program */
+int onenand_write_while_prog(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf);
+
/*
* onenand_state_t - chip states
* Enumeration for OneNAND flash chip state
--
1.5.4.3
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