mtd: atmel_nand: make PMECC lookup table and offset property optional

If there is no PMECC lookup table stored in ROM, or lookup table offset is
not specified, PMECC driver should build it in DDR by itself.

That make the PMECC driver work for some board which doesn't have PMECC
lookup table in ROM.

The PMECC use the BCH algorithm, so based on the build_gf_tables()
function in lib/bch.c, we can build the Galois Field lookup table.

For more information can refer to section 5.4 of PMECC controller
application note:
	http://www.atmel.com/images/doc11127.pdf

Signed-off-by: Josh Wu <josh.wu@atmel.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Josh Wu
2014-10-11 18:01:50 +08:00
committed by Brian Norris
parent 33a87a159c
commit abb1cd00e6
3 changed files with 85 additions and 6 deletions

View File

@@ -142,6 +142,10 @@
#define PMECC_GF_DIMENSION_13 13
#define PMECC_GF_DIMENSION_14 14
/* Primitive Polynomial used by PMECC */
#define PMECC_GF_13_PRIMITIVE_POLY 0x201b
#define PMECC_GF_14_PRIMITIVE_POLY 0x4443
#define PMECC_LOOKUP_TABLE_SIZE_512 0x2000
#define PMECC_LOOKUP_TABLE_SIZE_1024 0x4000