[PATCH] Adding nand lock/unlock routines.
Vimal Singh
vimalsingh at ti.com
Wed Jan 13 07:24:10 EST 2010
Adding nand lock / unlock routines. At least 'micron' parts
support this.
Signed-off-by: Vimal Singh <vimalsingh at ti.com>
---
drivers/mtd/nand/nand_base.c | 204 ++++++++++++++++++++++++++++++++++++++++++
include/linux/mtd/nand.h | 10 ++
2 files changed, 214 insertions(+), 0 deletions(-)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 8f2958f..4e27426 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -835,6 +835,208 @@ static int nand_wait(struct
}
/**
+ * __nand_unlock - [REPLACABLE] unlocks specified locked blockes
+ *
+ * @param mtd - mtd info
+ * @param ofs - offset to start unlock from
+ * @param len - length to unlock
+ * @invert - when = 0, unlock the range of blocks within the lower and
+ * upper boundary address
+ * whne = 1, unlock the range of blocks outside the boundaries
+ * of the lower and upper boundary address
+ *
+ * @return - unlock status
+ */
+static int __nand_unlock(struct mtd_info *mtd, loff_t ofs,
+ uint64_t len, int invert)
+{
+ int ret = 0;
+ int status, page;
+ struct nand_chip *chip = mtd->priv;
+
+ DEBUG(MTD_DEBUG_LEVEL3, "%s: start = 0x%012llx, len = %llu\n",
+ __func__, (unsigned long long)ofs, len);
+
+ /* Submit address of first page to unlock */
+ page = ofs >> chip->page_shift;
+ chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);
+
+ /* Submit address of last page to unlock */
+ page = (ofs + len) >> chip->page_shift;
+ chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1,
+ (page | invert) & chip->pagemask);
+
+ /* Call wait ready function */
+ status = chip->waitfunc(mtd, chip);
+ udelay(1000);
+ /* See if device thinks it succeeded */
+ if (status & 0x01) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Error status = 0x%08x\n",
+ __func__, status);
+ ret = -EIO;
+ }
+
+ return ret;
+}
+
+/**
+ * nand_unlock - [REPLACABLE] unlocks specified locked blockes
+ *
+ * @param mtd - mtd info
+ * @param ofs - offset to start unlock from
+ * @param len - length to unlock
+ *
+ * @return - unlock status
+ */
+int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ int ret = 0;
+ int chipnr;
+ struct nand_chip *chip = mtd->priv;
+
+ /* Start address must align on block boundary */
+ if (ofs & ((1 << chip->phys_erase_shift) - 1)) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Unaligned address\n", __func__);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Length must align on block boundary */
+ if (len & ((1 << chip->phys_erase_shift) - 1)) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Length not block aligned\n",
+ __func__);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Do not allow past end of device */
+ if (ofs + len > mtd->size) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Past end of device\n",
+ __func__);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Align to last block address if size addresses end of the device */
+ if (ofs + len == mtd->size)
+ len -= mtd->erasesize;
+
+ nand_get_device(chip, mtd, FL_UNLOCKING);
+
+ /* Shift to get chip number */
+ chipnr = ofs >> chip->chip_shift;
+
+ chip->select_chip(mtd, chipnr);
+
+ /* Check, if it is write protected */
+ if (nand_check_wp(mtd)) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Device is write protected!!!\n",
+ __func__);
+ ret = -EIO;
+ goto out;
+ }
+
+ ret = __nand_unlock(mtd, ofs, len, 0);
+
+out:
+ /* de-select the NAND device */
+ chip->select_chip(mtd, -1);
+
+ nand_release_device(mtd);
+
+ return ret;
+}
+
+/**
+ * nand_lock - [REPLACABLE] locks all blockes present in the device
+ *
+ * @param mtd - mtd info
+ * @param ofs - offset to start unlock from
+ * @param len - length to unlock
+ *
+ * @return - lock status
+ *
+ * This feature is not support in many NAND parts. 'Micron' NAND parts
+ * do have this feature, but it allows only to lock all blocks not for
+ * specified range for block.
+ *
+ * Implementing 'lock' feature by making use of 'unlock', for now.
+ */
+int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ int ret = 0;
+ int chipnr, status, page;
+ struct nand_chip *chip = mtd->priv;
+
+ DEBUG(MTD_DEBUG_LEVEL3, "%s: start = 0x%012llx, len = %llu\n",
+ __func__, (unsigned long long)ofs, len);
+
+ /* Start address must align on block boundary */
+ if (ofs & ((1 << chip->phys_erase_shift) - 1)) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Unaligned address\n", __func__);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Length must align on block boundary */
+ if (len & ((1 << chip->phys_erase_shift) - 1)) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Length not block aligned\n",
+ __func__);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Do not allow past end of device */
+ if (ofs + len > mtd->size) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Past end of device\n",
+ __func__);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ nand_get_device(chip, mtd, FL_LOCKING);
+
+ /* Shift to get chip number */
+ chipnr = ofs >> chip->chip_shift;
+
+ chip->select_chip(mtd, chipnr);
+
+ /* Check, if it is write protected */
+ if (nand_check_wp(mtd)) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Device is write protected!!!\n",
+ __func__);
+ status = MTD_ERASE_FAILED;
+ ret = -EIO;
+ goto out;
+ }
+
+ /* Submit address of first page to lock */
+ page = ofs >> chip->page_shift;
+ chip->cmdfunc(mtd, NAND_CMD_LOCK, -1, page & chip->pagemask);
+
+ /* Call wait ready function */
+ status = chip->waitfunc(mtd, chip);
+ udelay(1000);
+ /* See if device thinks it succeeded */
+ if (status & 0x01) {
+ DEBUG(MTD_DEBUG_LEVEL0, "%s: Error status = 0x%08x\n",
+ __func__, status);
+ ret = -EIO;
+ goto out;
+ }
+
+ ret = __nand_unlock(mtd, ofs, len, 0x1);
+
+out:
+ /* de-select the NAND device */
+ chip->select_chip(mtd, -1);
+
+ nand_release_device(mtd);
+
+ return ret;
+}
+
+/**
* nand_read_page_raw - [Intern] read raw page data without ecc
* @mtd: mtd info structure
* @chip: nand chip info structure
@@ -3077,6 +3279,8 @@ void nand_release(struct mtd_info *mtd)
kfree(chip->buffers);
}
+EXPORT_SYMBOL_GPL(nand_lock);
+EXPORT_SYMBOL_GPL(nand_unlock);
EXPORT_SYMBOL_GPL(nand_scan);
EXPORT_SYMBOL_GPL(nand_scan_ident);
EXPORT_SYMBOL_GPL(nand_scan_tail);
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index ccab9df..48bc2c5 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -38,6 +38,12 @@ extern void nand_release (struct
/* Internal helper for board drivers which need to override command function */
extern void nand_wait_ready(struct mtd_info *mtd);
+/* locks all blockes present in the device */
+extern int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+
+/* unlocks specified locked blockes */
+extern int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+
/* The maximum number of NAND chips in an array */
#define NAND_MAX_CHIPS 8
@@ -82,6 +88,10 @@ extern void nand_wait_ready(struct
#define NAND_CMD_ERASE2 0xd0
#define NAND_CMD_RESET 0xff
+#define NAND_CMD_LOCK 0x2a
+#define NAND_CMD_UNLOCK1 0x23
+#define NAND_CMD_UNLOCK2 0x24
+
/* Extended commands for large page devices */
#define NAND_CMD_READSTART 0x30
#define NAND_CMD_RNDOUTSTART 0xE0
--
1.5.5
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