[PATCH 2/3] mtd/nand : set Nand flash page address to FBAR and FPAR correctly

From: b35362
Date: Tue Nov 15 2011 - 05:44:00 EST


From: Liu Shuo <b35362@xxxxxxxxxxxxx>

If we use the Nand flash chip whose number of pages in a block is greater
than 64(for large page), we must treat the low bit of FBAR as being the
high bit of the page address due to the limitation of FCM, it simply uses
the low 6-bits (for large page) of the combined block/page address as the
FPAR component, rather than considering the actual block size.

Signed-off-by: Liu Shuo <b35362@xxxxxxxxxxxxx>
Signed-off-by: Jerry Huang <Chang-Ming.Huang@xxxxxxxxxxxxx>
Signed-off-by: Tang Yuantian <b29983@xxxxxxxxxxxxx>
Signed-off-by: Li Yang <leoli@xxxxxxxxxxxxx>
---
drivers/mtd/nand/fsl_elbc_nand.c | 13 ++++++++++---
1 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c
index 1bfcdef..c2c231b 100644
--- a/drivers/mtd/nand/fsl_elbc_nand.c
+++ b/drivers/mtd/nand/fsl_elbc_nand.c
@@ -166,15 +166,22 @@ static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)

elbc_fcm_ctrl->page = page_addr;

- out_be32(&lbc->fbar,
- page_addr >> (chip->phys_erase_shift - chip->page_shift));
-
if (priv->page_size) {
+ /*
+ * large page size chip : FPAR[PI] save the lowest 6 bits,
+ * FBAR[BLK] save the other bits.
+ */
+ out_be32(&lbc->fbar, page_addr >> 6);
out_be32(&lbc->fpar,
((page_addr << FPAR_LP_PI_SHIFT) & FPAR_LP_PI) |
(oob ? FPAR_LP_MS : 0) | column);
buf_num = (page_addr & 1) << 2;
} else {
+ /*
+ * small page size chip : FPAR[PI] save the lowest 5 bits,
+ * FBAR[BLK] save the other bits.
+ */
+ out_be32(&lbc->fbar, page_addr >> 5);
out_be32(&lbc->fpar,
((page_addr << FPAR_SP_PI_SHIFT) & FPAR_SP_PI) |
(oob ? FPAR_SP_MS : 0) | column);
--
1.7.1


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