From: Jeff Westfahl <jeff.westf...@ni.com>
Implement the new mtd function 'max_bad_blocks'. Use the ONFI parameter
page to find the maximum bad blocks to reserve for an MTD, taking into
account how many LUNs the MTD spans.
Signed-off-by: Jeff Westfahl <jeff.westf...@ni.com>
Signed-off-by: Zach Brown <zach.br...@ni.com>
---
drivers/mtd/nand/nand_base.c | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index e5718e5..ac08224 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -3226,6 +3226,39 @@ static int nand_block_markbad(struct mtd_info *mtd,
loff_t ofs)
}
/**
+ * nand_max_bad_blocks - [MTD Interface] Max number of bad blocks for an mtd
+ * @mtd: MTD device structure
+ * @ofs: offset relative to mtd start
+ * @len: length of mtd
+ */
+static int nand_max_bad_blocks(struct mtd_info *mtd, loff_t ofs, size_t len)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ uint32_t part_start_block;
+ uint32_t part_end_block;
+ uint32_t part_start_lun;
+ uint32_t part_end_lun;
+
+ /* ONFI is used to determine the maximum bad block count. */
+ if (!chip->onfi_version)
+ return -ENOTSUPP;
+
+ /* Get the start and end of the partition in erase blocks. */
+ part_start_block = mtd_div_by_eb(ofs, mtd);
+ part_end_block = mtd_div_by_eb(len, mtd) + part_start_block - 1;
+
+ /* Get the start and end LUNs of the partition. */
+ part_start_lun = part_start_block / chip->onfi_params.blocks_per_lun;
+ part_end_lun = part_end_block / chip->onfi_params.blocks_per_lun;
+
+ /* Look up the bad blocks per unit and multiply by the number of units
+ * that the partition spans.
+ */
+ return chip->onfi_params.bb_per_lun *
+ (part_end_lun - part_start_lun + 1);
+}
+
+/**
* nand_onfi_set_features- [REPLACEABLE] set features for ONFI nand
* @mtd: MTD device structure
* @chip: nand chip info structure
@@ -4743,6 +4776,7 @@ int nand_scan_tail(struct mtd_info *mtd)
mtd->_block_isreserved = nand_block_isreserved;
mtd->_block_isbad = nand_block_isbad;
mtd->_block_markbad = nand_block_markbad;
+ mtd->_max_bad_blocks = nand_max_bad_blocks;
mtd->writebufsize = mtd->writesize;
/*
--
2.7.4
