于 2011年12月09日 00:37, Marek Vasut 写道:
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 LiuShengzhou.Liu@freescale.com Signed-off-by: Liu Shuob35362@freescale.com
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