If ecc chunk data size is 512 and oobsize is bigger than 512, there is
a chance that block_mark_bit_offset conflicts with bch ecc area.
The following graph is modified from kernel gpmi-nand.c driver with
each data block 512 bytes. We can see that Block Mark conflicts with
ecc area from bch view. We can enlarge the ecc chunk size to avoid
this problem to those oobsize which is larger than 512.
| P |
|<----------------------------------------------------------------->|
| |
| (Block Mark) |
| P' | | | |
|<--------------------------------------------------->| D | | O'|
| |<--------->| |<->|
V V V V V
+---+--------------+-+--------------+-+--------------+-+----------+-+---+
| M | data |E| data |E| data |E| data |E| |
+---+--------------+-+--------------+-+--------------+-+----------+-+---+
^ ^
| O |
|<---------------->|
P : the page size for BCH module.
E : The ECC strength.
G : the length of Galois Field.
N : The chunk count of per page.
M : the metasize of per page.
C : the ecc chunk size, aka the "data" above.
P': the nand chip's page size.
O : the nand chip's oob size.
O': the free oob.
Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Tested-By: Tim Harvey <tharvey@gateworks.com>
The following headers are moved to a i.MX common location:
- regs-common.h
- regs-apbh.h
- regs-bch.h
- regs-gpmi.h
- dma.h
This way this header can be re-used also by other i.MX platforms.
For example the i.MX6 which will need it for the upcoming NAND
support.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
2013-04-22 10:22:22 +02:00
Renamed from arch/arm/include/asm/arch-mxs/regs-bch.h (Browse further)