[MTD] OneNAND: add subpage write support
Linux-MTD Mailing List
linux-mtd at lists.infradead.org
Thu Jan 11 09:59:02 EST 2007
Gitweb: http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=60d84f9739a47d0ed8e19805d9056e39fba31c79
Commit: 60d84f9739a47d0ed8e19805d9056e39fba31c79
Parent: f62724873652ddb19edf7f92843e9456fe3be3ea
Author: Kyungmin Park <kyungmin.park at samsung.com>
AuthorDate: Fri Dec 22 16:21:54 2006 +0900
Committer: Artem Bityutskiy <dedekind at infradead.org>
CommitDate: Wed Jan 10 14:35:00 2007 +0200
[MTD] OneNAND: add subpage write support
OneNAND supports up to 4 writes at one NAND page. Add support of this feature.
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
drivers/mtd/onenand/onenand_base.c | 56 +++++++++++++++++++++++++++---------
include/linux/mtd/onenand.h | 2 +
2 files changed, 44 insertions(+), 14 deletions(-)
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 3fab4d1..51fb840 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -192,8 +192,6 @@ static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
struct onenand_chip *this = mtd->priv;
int value, readcmd = 0, block_cmd = 0;
int block, page;
- /* Now we use page size operation */
- int sectors = 4, count = 4;
/* Address translation */
switch (cmd) {
@@ -245,6 +243,8 @@ static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
}
if (page != -1) {
+ /* Now we use page size operation */
+ int sectors = 4, count = 4;
int dataram;
switch (cmd) {
@@ -914,6 +914,10 @@ static int onenand_verify_page(struct mtd_info *mtd, u_char *buf, loff_t addr)
void __iomem *dataram0, *dataram1;
int ret = 0;
+ /* In partial page write, just skip it */
+ if ((addr & (mtd->writesize - 1)) != 0)
+ return 0;
+
this->command(mtd, ONENAND_CMD_READ, addr, mtd->writesize);
ret = this->wait(mtd, FL_READING);
@@ -936,7 +940,7 @@ static int onenand_verify_page(struct mtd_info *mtd, u_char *buf, loff_t addr)
#define onenand_verify_oob(...) (0)
#endif
-#define NOTALIGNED(x) ((x & (mtd->writesize - 1)) != 0)
+#define NOTALIGNED(x) ((x & (this->subpagesize - 1)) != 0)
/**
* onenand_write - [MTD Interface] write buffer to FLASH
@@ -954,6 +958,7 @@ static int onenand_write(struct mtd_info *mtd, loff_t to, size_t len,
struct onenand_chip *this = mtd->priv;
int written = 0;
int ret = 0;
+ int column, subpage;
DEBUG(MTD_DEBUG_LEVEL3, "onenand_write: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);
@@ -972,45 +977,61 @@ static int onenand_write(struct mtd_info *mtd, loff_t to, size_t len,
return -EINVAL;
}
+ column = to & (mtd->writesize - 1);
+ subpage = column || (len & (mtd->writesize - 1));
+
/* Grab the lock and see if the device is available */
onenand_get_device(mtd, FL_WRITING);
/* Loop until all data write */
while (written < len) {
- int thislen = min_t(int, mtd->writesize, len - written);
-
- this->command(mtd, ONENAND_CMD_BUFFERRAM, to, mtd->writesize);
+ int bytes = mtd->writesize;
+ int thislen = min_t(int, bytes, len - written);
+ u_char *wbuf = (u_char *) buf;
+
+ this->command(mtd, ONENAND_CMD_BUFFERRAM, to, bytes);
+
+ /* Partial page write */
+ if (subpage) {
+ bytes = min_t(int, bytes - column, (int) len);
+ memset(this->page_buf, 0xff, mtd->writesize);
+ memcpy(this->page_buf + column, buf, bytes);
+ wbuf = this->page_buf;
+ /* Even though partial write, we need page size */
+ thislen = mtd->writesize;
+ }
- this->write_bufferram(mtd, ONENAND_DATARAM, buf, 0, thislen);
+ this->write_bufferram(mtd, ONENAND_DATARAM, wbuf, 0, thislen);
this->write_bufferram(mtd, ONENAND_SPARERAM, ffchars, 0, mtd->oobsize);
this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
- onenand_update_bufferram(mtd, to, 1);
+ /* In partial page write we don't update bufferram */
+ onenand_update_bufferram(mtd, to, !subpage);
ret = this->wait(mtd, FL_WRITING);
if (ret) {
DEBUG(MTD_DEBUG_LEVEL0, "onenand_write: write filaed %d\n", ret);
- goto out;
+ break;
}
- written += thislen;
-
/* Only check verify write turn on */
- ret = onenand_verify_page(mtd, (u_char *) buf, to);
+ ret = onenand_verify_page(mtd, (u_char *) wbuf, to);
if (ret) {
DEBUG(MTD_DEBUG_LEVEL0, "onenand_write: verify failed %d\n", ret);
- goto out;
+ break;
}
+ written += thislen;
+
if (written == len)
break;
+ column = 0;
to += thislen;
buf += thislen;
}
-out:
/* Deselect and wake up anyone waiting on the device */
onenand_release_device(mtd);
@@ -2021,23 +2042,30 @@ int onenand_scan(struct mtd_info *mtd, int maxchips)
init_waitqueue_head(&this->wq);
spin_lock_init(&this->chip_lock);
+ /*
+ * Allow subpage writes up to oobsize.
+ */
switch (mtd->oobsize) {
case 64:
this->ecclayout = &onenand_oob_64;
+ mtd->subpage_sft = 2;
break;
case 32:
this->ecclayout = &onenand_oob_32;
+ mtd->subpage_sft = 1;
break;
default:
printk(KERN_WARNING "No OOB scheme defined for oobsize %d\n",
mtd->oobsize);
+ mtd->subpage_sft = 0;
/* To prevent kernel oops */
this->ecclayout = &onenand_oob_32;
break;
}
+ this->subpagesize = mtd->writesize >> mtd->subpage_sft;
mtd->ecclayout = this->ecclayout;
/* Fill in remaining MTD driver data */
diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h
index 62ca0f4..fe3500d 100644
--- a/include/linux/mtd/onenand.h
+++ b/include/linux/mtd/onenand.h
@@ -88,6 +88,7 @@ struct onenand_bufferram {
* operation is in progress
* @state: [INTERN] the current state of the OneNAND device
* @page_buf: data buffer
+ * @subpagesize: [INTERN] holds the subpagesize
* @ecclayout: [REPLACEABLE] the default ecc placement scheme
* @bbm: [REPLACEABLE] pointer to Bad Block Management
* @priv: [OPTIONAL] pointer to private chip date
@@ -128,6 +129,7 @@ struct onenand_chip {
onenand_state_t state;
unsigned char *page_buf;
+ int subpagesize;
struct nand_ecclayout *ecclayout;
void *bbm;
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