On 12/06/2011 09:55 PM, LiuShuo wrote: > 于 2011年12月07日 08:09, Scott Wood 写道: >> On 12/03/2011 10:31 PM, shuo....@freescale.com wrote: >>> From: Liu Shuo<shuo....@freescale.com> >>> >>> Freescale FCM controller has a 2K size limitation of buffer RAM. In >>> order >>> to support the Nand flash chip whose page size is larger than 2K bytes, >>> we read/write 2k data repeatedly by issuing FIR_OP_RB/FIR_OP_WB and save >>> them to a large buffer. >>> >>> Signed-off-by: Liu Shuo<shuo....@freescale.com> >>> --- >>> v3: >>> -remove page_size of struct fsl_elbc_mtd. >>> -do a oob write by NAND_CMD_RNDIN. >>> >>> drivers/mtd/nand/fsl_elbc_nand.c | 243 >>> ++++++++++++++++++++++++++++++++++---- >>> 1 files changed, 218 insertions(+), 25 deletions(-) >> What is the plan for bad block marker migration? > This patch has been ported to uboot now, I think we can make a special > uboot image for bad > block marker migration when first use the chip.
It should not be a special image, and there should be some way to mark that the migration has happened. Even if we do the migration in U-Boot, Linux could check for the marker and if absent, disallow access and tell the user to run the migration tool. >>> @@ -473,13 +568,72 @@ static void fsl_elbc_cmdfunc(struct mtd_info >>> *mtd, unsigned int command, >>> * write so the HW generates the ECC. >>> */ >>> if (elbc_fcm_ctrl->oob || elbc_fcm_ctrl->column != 0 || >>> - elbc_fcm_ctrl->index != mtd->writesize + mtd->oobsize) >>> - out_be32(&lbc->fbcr, >>> - elbc_fcm_ctrl->index - elbc_fcm_ctrl->column); >>> - else >>> + elbc_fcm_ctrl->index != mtd->writesize + mtd->oobsize) { >>> + if (elbc_fcm_ctrl->oob&& mtd->writesize> 2048) { >>> + out_be32(&lbc->fbcr, 64); >>> + } else { >>> + out_be32(&lbc->fbcr, elbc_fcm_ctrl->index >>> + - elbc_fcm_ctrl->column); >>> + } >> We need to limit ourselves to the regions that have actually been >> written to in the buffer. fbcr needs to be set separately for first and >> last subpages, with intermediate subpages having 0, 64, or 2112 as >> appropriate. Subpages that are entirely before column or entirely after >> column + index should be skipped. > > I have considered this case, but I don't think it is useful. > 1.There isn't a 'length' parameter in driver interface, although we > can get it from 'index - column'. Right. column is start, and index is end + 1. We have the bounds of what has been written. > 2.To see nand_do_write_oob() in nand_base.c, it fill '0xff' to > entire oob area first and write the user data by nand_fill_oob(), then > call ecc.write_oob (default is nand_write_oob_std()). Do we really want to assume that that's what it will always do? And if we do want to make such assumptions, we could rip out all usage of index/column here, and just handle "oob" and "full page" cases. -Scott _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev