- * The function checks, if a bad block table(s) is/are already
- * available. If not it scans the device for manufacturer
- * marked good / bad blocks and writes the bad block table(s) to
- * the selected place.
+ * This functions performs a few sanity checks on the bad block description
+ * table.
+ */
+static void verify_bbt_descr(struct mtd_info *mtd, struct nand_bbt_descr *bd)
+{
+ struct nand_chip *this = mtd->priv;
+ u32 pattern_len;
+ u32 bits;
+ u32 table_size;
+
+ if (!bd)
+ return;
+
+ pattern_len = bd->len;
+ bits = bd->options & NAND_BBT_NRBITS_MSK;
+
+ BUG_ON((this->bbt_options & NAND_BBT_NO_OOB) &&
+ !(this->bbt_options & NAND_BBT_USE_FLASH));
+ BUG_ON(!bits);
+
+ if (bd->options & NAND_BBT_VERSION)
+ pattern_len++;
+
+ if (bd->options & NAND_BBT_NO_OOB) {
+ BUG_ON(!(this->bbt_options & NAND_BBT_USE_FLASH));
+ BUG_ON(!(this->bbt_options & NAND_BBT_NO_OOB));
+ BUG_ON(bd->offs);
+ if (bd->options & NAND_BBT_VERSION)
+ BUG_ON(bd->veroffs != bd->len);
+ BUG_ON(bd->options & NAND_BBT_SAVECONTENT);
+ }
+
+ if (bd->options & NAND_BBT_PERCHIP)
+ table_size = this->chipsize >> this->bbt_erase_shift;
+ else
+ table_size = mtd->size >> this->bbt_erase_shift;
+ table_size >>= 3;
+ table_size *= bits;
+ if (bd->options & NAND_BBT_NO_OOB)
+ table_size += pattern_len;
+ BUG_ON(table_size > (1 << this->bbt_erase_shift));
+}
+
+/**
+ * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s)
+ * @mtd: MTD device structure
+ * @bd: descriptor for the good/bad block search pattern