3  *   Bad block table support for the NAND driver
13  * When nand_scan_bbt is called, then it tries to find the bad block table
16  * marked good / bad blocks. This information is used to create a memory BBT.
17  * Once a new bad block is discovered then the "factory" information is updated
24  * If the tables are not versioned, then we "or" the bad block information.
27  * good / bad blocks and the bad block tables are created.
32  * The auto generated bad block table is located in the last good blocks
43  * 00b:		block is factory marked bad
44  * 01b, 10b:	block is marked bad due to wear
46  * The memory bad block table uses the following scheme:
48  * 01b:		block is marked bad due to wear
50  * 11b:		block is factory marked bad
52  * Multichip devices like DOC store the bad block info per floor.
109  * Check for a pattern at the given place. Used to search bad block tables and
110  * good / bad block identifiers.
129  * Check for a pattern at the given place. Used to search bad block tables and
130  * good / bad block identifiers. Same as check_pattern, but no optional empty
161  * read_bbt - [GENERIC] Read the bad block table starting from page
169  * Read the bad block table starting from page.
234 				pr_info("nand_read_bbt: bad block at 0x%012llx\n",  in read_bbt()
237 				/* Factory marked bad or worn out? */  in read_bbt()
254  * read_abs_bbt - [GENERIC] Read the bad block table starting at a given page
257  * @td: descriptor for the bad block table
261  * Read the bad block table for all chips starting at a given page. We assume
379  * read_abs_bbts - [GENERIC] Read the bad block table(s) for all chips starting at a given page
382  * @td: descriptor for the bad block table
383  * @md:	descriptor for the bad block table mirror
385  * Read the bad block table(s) for all chips starting at a given page. We
398 		pr_info("Bad block table at page %d, version 0x%02X\n",  in read_abs_bbts()
407 		pr_info("Bad block table at page %d, version 0x%02X\n",  in read_abs_bbts()
444  * create_bbt - [GENERIC] Create a bad block table by scanning the device
447  * @bd: descriptor for the good/bad block search pattern
451  * Create a bad block table by scanning the device for the given good/bad block
462 	pr_info("Scanning device for bad blocks\n");  in create_bbt()
499 			pr_warn("Bad eraseblock %d at 0x%012llx\n",  in create_bbt()
510  * search_bbt - [GENERIC] scan the device for a specific bad block table
513  * @td: descriptor for the bad block table
515  * Read the bad block table by searching for a given ident pattern. Search is
519  * the bad block information of this chip. This is necessary to provide support
578 			pr_warn("Bad block table not found for chip %d\n", i);  in search_bbt()
580 			pr_info("Bad block table found at page %d, version 0x%02X\n",  in search_bbt()
587  * search_read_bbts - [GENERIC] scan the device for bad block table(s)
590  * @td: descriptor for the bad block table
591  * @md: descriptor for the bad block table mirror
593  * Search and read the bad block table(s).
616  * all blocks are already used of marked bad. If td->pages[chip] was already
639 	 * Automatic placement of the bad block table. Search direction  in get_bbt_block()
653 		/* Check, if the block is bad */  in get_bbt_block()
671  * mark_bbt_block_bad - Mark one of the block reserved for BBT bad
677  * Blocks reserved for BBT can become bad. This functions is an helper to mark
678  * such blocks as bad. It takes care of updating the in-memory BBT, marking the
679  * block as bad using a bad block marker and invalidating the associated
695 		pr_warn("nand_bbt: error %d while marking block %d bad\n",  in mark_bbt_block_bad()
702  * write_bbt - [GENERIC] (Re)write the bad block table
705  * @td: descriptor for the bad block table
706  * @md: descriptor for the bad block table mirror
709  * (Re)write the bad block table.
733 	/* Write bad block table per chip rather than per device? */  in write_bbt()
754 			pr_err("No space left to write bad block table\n");  in write_bbt()
794 					pr_info("nand_bbt: error reading block for writing the bad block table\n");  in write_bbt()
797 				pr_warn("nand_bbt: ECC error while reading block for writing bad block table\n");  in write_bbt()
875 		pr_info("Bad block table written to 0x%012llx, version 0x%02X\n",  in write_bbt()
884 	pr_warn("nand_bbt: error while writing bad block table %d\n", res);  in write_bbt()
889  * nand_memory_bbt - [GENERIC] create a memory based bad block table
891  * @bd: descriptor for the good/bad block search pattern
894  * manufacturer / software marked good / bad blocks.
907  * @bd: descriptor for the good/bad block search pattern
968 			/* Create the bad block table by scanning the device? */  in check_create()
1014 		/* Write the bad block table to the device? */  in check_create()
1021 		/* Write the mirror bad block table to the device? */  in check_create()
1032  * mark_bbt_regions - [GENERIC] mark the bad block table regions
1034  * @td: bad block table descriptor
1036  * The bad block table regions are marked as "bad" to prevent accidental
1092  * verify_bbt_descr - verify the bad block description
1096  * This functions performs a few sanity checks on the bad block description
1140  * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s)
1142  * @bd: descriptor for the good/bad block search pattern
1144  * The function checks, if a bad block table(s) is/are already available. If
1145  * not it scans the device for manufacturer marked good / bad blocks and writes
1146  * the bad block table(s) to the selected place.
1148  * The bad block table memory is allocated here. It must be freed by calling
1161 	 * Allocate memory (2bit per block) and clear the memory bad block  in nand_scan_bbt()
1170 	 * memory based bad block table.  in nand_scan_bbt()
1195 		/* Search the bad block table using a pattern in oob */  in nand_scan_bbt()
1218  * nand_update_bbt - update bad block table(s)
1222  * The function updates the bad block table(s).
1256 	/* Write the bad block table to the device? */  in nand_update_bbt()
1262 	/* Write the mirror bad block table to the device? */  in nand_update_bbt()
1273  * Define some generic bad / good block scan pattern which are used
1274  * while scanning a device for factory marked good / bad blocks.
1336 		pr_warn("Bad block pattern already allocated; not replacing\n");  in nand_create_badblock_pattern()
1352  * nand_create_bbt - [NAND Interface] Select a default bad block table for the device
1355  * This function selects the default bad block table support for the device and
1362 	/* Is a flash based bad block table requested? */  in nand_create_bbt()
1404  * nand_isbad_bbt - [NAND Interface] Check if a block is bad
1407  * @allowbbt: allow access to bad block table region
1432  * nand_markbad_bbt - [NAND Interface] Mark a block bad in the BBT
1434  * @offs: offset of the bad block
1443 	/* Mark bad block in memory */  in nand_markbad_bbt()
1446 	/* Update flash-based bad block table */  in nand_markbad_bbt()