From 8f42bf1c393d53a70c2545e9f329d11c46d74794 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Fri, 27 Jun 2008 23:04:13 +0400 Subject: [PATCH] fsl_elbc_nand: implement support for flash-based BBT This patch implements support for flash-based BBT for chips working through ELBC NAND controller, so that NAND core will not have to re-scan for bad blocks on every boot. Because ELBC controller may provide HW-generated ECCs we should adjust bbt pattern and bbt version positions in the OOB free area. Signed-off-by: Anton Vorontsov Signed-off-by: David Woodhouse Signed-off-by: Scott Wood --- drivers/mtd/nand/fsl_elbc_nand.c | 35 +++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c index b8bc143a8c..e4e4de0870 100644 --- a/drivers/mtd/nand/fsl_elbc_nand.c +++ b/drivers/mtd/nand/fsl_elbc_nand.c @@ -136,6 +136,34 @@ static struct nand_bbt_descr largepage_memorybased = { .pattern = scan_ff_pattern, }; +/* + * ELBC may use HW ECC, so that OOB offsets, that NAND core uses for bbt, + * interfere with ECC positions, that's why we implement our own descriptors. + * OOB {11, 5}, works for both SP and LP chips, with ECCM = 1 and ECCM = 0. + */ +static u8 bbt_pattern[] = {'B', 'b', 't', '0' }; +static u8 mirror_pattern[] = {'1', 't', 'b', 'B' }; + +static struct nand_bbt_descr bbt_main_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE | + NAND_BBT_2BIT | NAND_BBT_VERSION, + .offs = 11, + .len = 4, + .veroffs = 15, + .maxblocks = 4, + .pattern = bbt_pattern, +}; + +static struct nand_bbt_descr bbt_mirror_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE | + NAND_BBT_2BIT | NAND_BBT_VERSION, + .offs = 11, + .len = 4, + .veroffs = 15, + .maxblocks = 4, + .pattern = mirror_pattern, +}; + /*=================================*/ /* @@ -738,7 +766,12 @@ int board_nand_init(struct nand_chip *nand) nand->waitfunc = fsl_elbc_wait; /* set up nand options */ - nand->options = NAND_NO_READRDY | NAND_NO_AUTOINCR; + nand->bbt_td = &bbt_main_descr; + nand->bbt_md = &bbt_mirror_descr; + + /* set up nand options */ + nand->options = NAND_NO_READRDY | NAND_NO_AUTOINCR | + NAND_USE_FLASH_BBT; nand->controller = &elbc_ctrl->controller; nand->priv = priv; -- 2.39.5