[PATCH v3] mtd: gpmi: Bitflip support in erased regions

[Elie De Brauwer <eliedebrauwer@gmail.com>]

Hello All,

This is v3 of my patch which adds support for bitflip detection/correction
in erased regions when using BCH/GPMI nand.

Changes in V3:
 - The fast path in V2 was not entered (my bad, I mixed some boards when
testing) due to using a faulty register offset. The fast path implemention
for correctly reading fully erased blocks is now functional (and properly 
tested). 
 - Also the fast path even become a bit faster since we now break out of
the for loop as soon as we see a properly erased block (instead of briefly
touching all sectors).
 - The ERASE_THRESHOLD aka the number of bitflips in erased regions we 
tolerate is no longer set to ecc_strength but to gf_len/2.
 - Several cosmetic changes.

Main credit to the above goes to Huang Shijie, thanks a lot !

Further comments/feedback welcome, but at this point I don't see any other
open points.

E.


Elie De Brauwer (1):
  mtd: gpmi: Deal with bitflips in erased regions regions

 drivers/mtd/nand/gpmi-nand/bch-regs.h  |    2 ++
 drivers/mtd/nand/gpmi-nand/gpmi-lib.c  |   16 ++++++++++++
 drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   44 +++++++++++++++++++++++++++++---
 drivers/mtd/nand/gpmi-nand/gpmi-nand.h |    1 +
 4 files changed, 60 insertions(+), 3 deletions(-)

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1.7.10.4