mtd: nand: support alternate BB marker locations on MLC (b60b08b0) · Commits · 戴 / test

This is a slightly modified version of a patch submitted last year by Reuben Dowle <reuben.dowle@navico.com>. His original comments follow: This patch adds support for some MLC NAND flashes that place the BB marker in the LAST page of the bad block rather than the FIRST page used for SLC NAND and other types of MLC nand. Lifted from Samsung datasheet for K9LG8G08U0A (1Gbyte MLC NAND): " Identifying Initial Invalid Block(s) All device locations are erased(FFh) except locations where the initial invalid block(s) information is written prior to shipping. The initial invalid block(s) status is defined by the 1st byte in the spare area. Samsung makes sure that the last page of every initial invalid block has non-FFh data at the column address of 2,048. ... " As far as I can tell, this is the same for all Samsung MLC nand, and in fact the samsung bsp for the processor used in our project (s3c6410) actually contained a hack similar to this patch but less portable to enable use of their NAND parts. I discovered this problem when trying to use a Micron NAND which does not used this layout - I wish samsung would put their stuff in main-line to avoid this type of problem. Currently this patch causes all MLC nand with manufacturer codes from Samsung and ST(Numonyx) to use this alternative location, since these are the manufactures that I know of that use this layout. Signed-off-by:

Kevin Cernekee <cernekee@gmail.com> Signed-off-by:

David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/nand_base.c

+15 −0

Original line number	Diff line number	Diff line
		@@ -347,6 +347,9 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
		struct nand_chip *chip = mtd->priv;
		u16 bad;

		if (chip->options & NAND_BB_LAST_PAGE)
		ofs += mtd->erasesize - mtd->writesize;

		page = (int)(ofs >> chip->page_shift) & chip->pagemask;

		if (getchip) {
		@@ -396,6 +399,9 @@ static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
		uint8_t buf[2] = { 0, 0 };
		int block, ret;

		if (chip->options & NAND_BB_LAST_PAGE)
		ofs += mtd->erasesize - mtd->writesize;

		/* Get block number */
		block = (int)(ofs >> chip->bbt_erase_shift);
		if (chip->bbt)
		@@ -2933,6 +2939,15 @@ static struct nand_flash_dev nand_get_flash_type(struct mtd_info mtd,
		if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
		chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;

		/*
		* Bad block marker is stored in the last page of each block
		* on Samsung and Hynix MLC devices
		*/
		if ((chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
		(*maf_id == NAND_MFR_SAMSUNG \|\|
		*maf_id == NAND_MFR_HYNIX))
		chip->options \|= NAND_BB_LAST_PAGE;

		/* Check for AND chips with 4 page planes */
		if (chip->options & NAND_4PAGE_ARRAY)
		chip->erase_cmd = multi_erase_cmd;

drivers/mtd/nand/nand_bbt.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -432,6 +432,9 @@ static int create_bbt(struct mtd_info mtd, uint8_t buf,
		from = (loff_t)startblock << (this->bbt_erase_shift - 1);
		}

		if (this->options & NAND_BB_LAST_PAGE)
		from += mtd->erasesize - (mtd->writesize * len);

		for (i = startblock; i < numblocks;) {
		int ret;

include/linux/mtd/nand.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -181,6 +181,8 @@ typedef enum {
		#define NAND_NO_READRDY 0x00000100
		/* Chip does not allow subpage writes */
		#define NAND_NO_SUBPAGE_WRITE 0x00000200
		/* Chip stores bad block marker on the last page of the eraseblock */
		#define NAND_BB_LAST_PAGE 0x00000400

		/* Device is one of 'new' xD cards that expose fake nand command set */
		#define NAND_BROKEN_XD 0x00000400

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