From mboxrd@z Thu Jan 1 00:00:00 1970 From: LiuShuo Date: Fri, 9 Dec 2011 10:33:57 +0800 Subject: [U-Boot] [PATCH 5/5] mtd/nand: workaround for Freescale FCM to support 4k pagesize Nand chip In-Reply-To: <201112081737.22273.marek.vasut@gmail.com> References: <1323341352-14996-1-git-send-email-Shengzhou.Liu@freescale.com> <1323341352-14996-4-git-send-email-Shengzhou.Liu@freescale.com> <1323341352-14996-5-git-send-email-Shengzhou.Liu@freescale.com> <201112081737.22273.marek.vasut@gmail.com> Message-ID: <4EE17395.5010308@freescale.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de ? 2011?12?09? 00:37, Marek Vasut ??: >> 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: Shengzhou Liu >> Signed-off-by: Liu Shuo >> --- >> drivers/mtd/nand/fsl_elbc_nand.c | 279 >> +++++++++++++++++++++++++++++++++---- 1 files changed, 248 insertions(+), >> 31 deletions(-) >> >> diff --git a/drivers/mtd/nand/fsl_elbc_nand.c >> b/drivers/mtd/nand/fsl_elbc_nand.c index 52362b1..3983c8c 100644 >> --- a/drivers/mtd/nand/fsl_elbc_nand.c >> +++ b/drivers/mtd/nand/fsl_elbc_nand.c >> @@ -64,7 +64,6 @@ struct fsl_elbc_mtd { >> struct device *dev; >> int bank; /* Chip select bank number */ >> u8 __iomem *vbase; /* Chip select base virtual address */ >> - int page_size; /* NAND page size (0=512, 1=2048) */ >> unsigned int fmr; /* FCM Flash Mode Register value */ >> }; >> >> @@ -85,6 +84,8 @@ struct fsl_elbc_ctrl { >> unsigned int mdr; /* UPM/FCM Data Register value */ >> unsigned int use_mdr; /* Non zero if the MDR is to be set */ >> unsigned int oob; /* Non zero if operating on OOB data */ >> + char *buffer; /* just used when pagesize is greater */ > Start sentence with capital letter > >> + /* than FCM RAM 2K limitation */ >> }; >> >> /* These map to the positions used by the FCM hardware ECC generator */ >> @@ -159,6 +160,44 @@ static struct nand_bbt_descr bbt_mirror_descr = { >> .pattern = mirror_pattern, >> }; >> >> +static void io_to_buffer(struct mtd_info *mtd, int subpage, int oob) >> +{ >> + struct nand_chip *chip = mtd->priv; >> + struct fsl_elbc_mtd *priv = chip->priv; >> + struct fsl_elbc_ctrl *ctrl = priv->ctrl; >> + void *src, *dst; >> + int len = (oob ? 64 : 2048); > No parenthesis ... > >> + >> + /* for emulating 4096+ bytes NAND using 2048-byte FCM RAM */ >> + if (oob) >> + dst = ctrl->buffer + mtd->writesize + subpage * 64; >> + else >> + dst = ctrl->buffer + subpage * 2048; > subpage * len ? dst = ctrl->buffer + (oob ? mtd->writesize : 0) + subpage * len ? Is this important ? I think it is ok. -LiuShuo > >> + >> + src = ctrl->addr + (oob ? 2048 : 0); >> + memcpy_fromio(dst, src, len); >> +} >> + >> +static void buffer_to_io(struct mtd_info *mtd, int subpage, int oob) >> +{ >> + struct nand_chip *chip = mtd->priv; >> + struct fsl_elbc_mtd *priv = chip->priv; >> + struct fsl_elbc_ctrl *ctrl = priv->ctrl; >> + void *src, *dst; >> + int len = (oob ? 64 : 2048); >> + >> + if (oob) >> + src = ctrl->buffer + mtd->writesize + subpage * 64; >> + else >> + src = ctrl->buffer + subpage * 2048; > DTTO > > M >