Commit Graph

77 Commits

Author SHA1 Message Date
Richard Genoud 61de9da657 mtd: nand: use NAND_BBT_SCAN_MAXBLOCKS
In nand_bbt.c, a hardcoded value was used instead of the define meant
for that, so we use the define.

There's no functional change.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 15:54:10 +01:00
Fabio Estevam d159c4e5fb mtd: nand: nand_bbt: export nand_update_bbt
When building MTD_NAND_GPMI_NAND as module, the following error shows up:

ERROR: "nand_update_bbt" [drivers/mtd/nand/gpmi-nand/gpmi_nand.ko] undefined!

Export nand_update_bbt to fix it.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 15:11:27 +01:00
Shmulik Ladkani eceb84b188 mtd: nand: rename create_bbt()'s 'len' variable to 'numpages'
Rename 'len' variable of create_bbt/scan_block_fast/scan_block_full to
'numpages', since it really means number of pages to scan when
searching for the BBM (and not the byte length of the scan).

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 15:10:37 +01:00
Brian Norris af69dcd386 mtd: nand: rename '_raw' BBT scan functions
None of these scanning functions use MTD_OPS_RAW mode any more, so there's
really nothing 'raw' about them. Rename them to (hopefully) make the code
a little clearer.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:52:04 +01:00
Brian Norris a7e68834fc mtd: nand: use ECC, if present, when scanning OOB
scan_read_raw_oob() is used in only in places where the MTD_OPS_PLACE_OOB mode
is preferable to MTD_OPS_RAW mode, so use MTD_OPS_PLACE_OOB instead.
MTD_OPS_PLACE_OOB provides the same functionality with the potential[1] added
bonus of error correction.

This brings scan_block_full() in line with scan_block_fast() so that they
both read bad block markers with MTD_OPS_PLACE_OOB. This can help in
preventing 0xff markers (in good blocks) from being interpreted as bad
block indicators in the presence of a single bitflip.

Note that ECC error codes (EUCLEAN or EBADMSG) are already silently
ignored in all users of scan_read_raw_oob().

[1] Few  drivers perform proper error correction on OOB data. In those
    cases, the use of MTD_OPS_RAW vs. MTD_OPS_PLACE_OOB is not
    significant.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:51:55 +01:00
Brian Norris 491ed06f33 mtd: nand_bbt: use string library
Some nand_bbt code can be shortened by using memcmp() and memchr_inv().
As an added bonus, there is a possible performance benefit.

Borrowed some code from Akinobu Mita.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:51:13 +01:00
Brian Norris 7b5a2d4097 mtd: nand: remove unused 'int' return codes
The return codes for read_abs_bbts() and search_read_bbts() are always
non-zero, and so don't have much meaning. Just remove them.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:51:00 +01:00
Huang Shijie 44ed0ffdbc mtd: fix typo in comment
fix the comment for nand_bbt.c

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-16 21:45:05 +01:00
Brian Norris 718894ad94 mtd: nand_bbt: refactor check_pattern_no_oob()
This function only returns 0 or -1, so make that clear.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 18:17:08 +01:00
Brian Norris 9fd6b37a08 mtd: nand: rename "no_bbt" descriptors to "no_oob"
These descriptors are for BBT's that don't use OOB; the "no_bbt" name doesn't
really make sense.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 18:17:08 +01:00
Shmulik Ladkani 7bb9c75436 mtd: nand: Use the mirror BBT descriptor when reading its version
The code responsible for reading the version of the mirror bbt was
incorrectly using the descriptor of the main bbt.

Pass the mirror bbt descriptor to 'scan_read_raw' when reading the
version of the mirror bbt.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: stable@vger.kernel.org [v2.6.37+]
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 18:17:06 +01:00
Dmitry Maluka 34a5704d91 mtd: nand: fix scan_read_raw_oob
It seems there is a bug in scan_read_raw_oob() in nand_bbt.c which
should cause wrong functioning of NAND_BBT_SCANALLPAGES option.

Artem: the patch did not apply and I had to amend it a bit.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org
2012-05-29 11:14:58 +03:00
Artem Bityutskiy a2cc5ba075 mtd: introduce mtd_write_oob interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:24 +00:00
Artem Bityutskiy fd2819bbc9 mtd: introduce mtd_read_oob interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:23 +00:00
Artem Bityutskiy 329ad399a9 mtd: introduce mtd_read interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:19 +00:00
Linus Torvalds e0d65113a7 Merge git://git.infradead.org/mtd-2.6
* git://git.infradead.org/mtd-2.6: (226 commits)
  mtd: tests: annotate as DANGEROUS in Kconfig
  mtd: tests: don't use mtd0 as a default
  mtd: clean up usage of MTD_DOCPROBE_ADDRESS
  jffs2: add compr=lzo and compr=zlib options
  jffs2: implement mount option parsing and compression overriding
  mtd: nand: initialize ops.mode
  mtd: provide an alias for the redboot module name
  mtd: m25p80: don't probe device which has status of 'disabled'
  mtd: nand_h1900 never worked
  mtd: Add DiskOnChip G3 support
  mtd: m25p80: add EON flash EN25Q32B into spi flash id table
  mtd: mark block device queue as non-rotational
  mtd: r852: make r852_pm_ops static
  mtd: m25p80: add support for at25df321a spi data flash
  mtd: mxc_nand: preset_v1_v2: unlock all NAND flash blocks
  mtd: nand: switch `check_pattern()' to standard `memcmp()'
  mtd: nand: invalidate cache on unaligned reads
  mtd: nand: do not scan bad blocks with NAND_BBT_NO_OOB set
  mtd: nand: wait to set BBT version
  mtd: nand: scrub BBT on ECC errors
  ...

Fix up trivial conflicts:
 - arch/arm/mach-at91/board-usb-a9260.c
	Merged into board-usb-a926x.c
 - drivers/mtd/maps/lantiq-flash.c
	add_mtd_partitions -> mtd_device_register vs changed to use
	mtd_device_parse_register.
2011-11-07 09:11:16 -08:00
Paul Gortmaker f3bcc0179a mtd: Add export.h for EXPORT_SYMBOL/THIS_MODULE where needed
These two common macros will be no longer present everywhere.
Call out the include needs of them explicitly where required.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:11 -04:00
Brian Norris 75b66d8ccd mtd: nand: switch `check_pattern()' to standard `memcmp()'
A portion of the `check_pattern()' function is basically a `memcmp()'.
Since it's possible for `memcmp()' to be optimized for a particular
architecture, we should use it instead.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:08 +03:00
Brian Norris 752ed6c5f8 mtd: nand: do not scan bad blocks with NAND_BBT_NO_OOB set
Updates to our default function for creating bad block patterns have
broken the "no OOB" feature. The NAND_BBT_NO_OOB option should not be
set while scanning for bad blocks, but we've been passing all BBT
options from nand_chip.bbt_options to the bad block scan. This causes us
to hit the:

	BUG_ON(bd->options & NAND_BBT_NO_OOB);

in create_bbt() when we scan the flash for bad blocks.

Thus, while it can be legal to set NAND_BBT_NO_OOB in a custom badblock
pattern descriptor (presumably with NAND_BBT_CREATE disabled?), we
should not pass it through in our default function.

Also, to help clarify and emphasize that the function creates bad block
patterns only (not, for example, table descriptors for locating
flash-based BBT), I renamed `nand_create_default_bbt_descr' to
`nand_create_badblock_pattern'.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:08 +03:00
Brian Norris dadc17a3e3 mtd: nand: wait to set BBT version
Because there are so many cases of checking, writing, and re-writing of
the bad block table(s), we might as well wait until the we've settled on
a valid, clean copy of the table. This also prevents us from falsely
incrementing the table version. For example, we may have the following:

  Primary table, with version 0x02
  Mirror table, with version 0x01
  Primary table has uncorrectable ECC errors

If we don't have this fix applied, then we will:

  Choose to read the primary table (higher version)
  Set mirror table version to 0x02
  Read back primary table
  Invalidate table because of ECC errors
  Retry readback operation with mirror table, now version 0x02
  Mirrored table reads cleanly
  Writeback BBT to primary table location (with "version 0x02")

However, the mirrored table shouldn't have a new version number.
Instead, we actually want:

  Choose to read the primary table (higher version)
  Read back primary table
  Invalidate table because of ECC errors
  Retry readback with mirror table (version 0x01)
  Mirrored table reads cleanly
  Set both tables to version 0x01
  Writeback BBT to primary table location (version 0x01)

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:08 +03:00
Brian Norris 623978de36 mtd: nand: scrub BBT on ECC errors
Now that `read_bbt()' returns ECC error codes properly, we handle those
codes when checking the integrity of our flash-based BBT.

The modifications can be described by this new policy:

*) On any uncorrected ECC error, we invalidate the corresponding table
   and retry our version-checking integrity logic.
*) On corrected bitflips, we mark both tables for re-writing to flash
   (a.k.a. scrubbing).

Current integrity checks (i.e., comparing version numbers, etc.) should
take care of all the cases that result in rescanning the device for bad
blocks or falling back to the BBT as found in the mirror descriptor.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:07 +03:00
Brian Norris 167a8d5250 mtd: nand: report ECC errors properly when reading BBT
Instead of just printing a warning when encountering ECC errors, we
should return a proper error status and print a more informative
warning. Later, we will handle these error messages in the upper layers
of the BBT scan.

Note that this patch makes our check for ECC error codes a little bit
more restrictive, leaving all unrecognized errors to the generic "else"
clause. This shouldn't cause problems and could even be a benefit.

This code is based on some findings reported by Matthieu Castet.

Reported-by: Matthieu CASTET <matthieu.castet@parrot.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:07 +03:00
Brian Norris d57f40544a mtd: utilize `mtd_is_*()' functions
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:06 +03:00
Brian Norris b61bf5bbf6 mtd: nand: remove gotos in `check_create()'
This is a second step in restructuring `check_create()'. When we don't
rely on goto statements for our main functionality, the code will become
a little easier to manipulate.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 17:16:03 +03:00
Brian Norris c5e8ef9c21 mtd: nand: begin restructuring check_create
We will begin restructuring the code for check_create so that we can
make some important changes. For now, we should just begin to get rid of
some goto statements to make things cleaner. This is the first step of a
few, which are separated to make them easier to follow.

This step should just be a code refactor.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 17:15:56 +03:00
Brian Norris 596d74527a mtd: nand: fix style
Remove some extra spaces
Consistently use '0x' prefix for bitfield-like constants
Spelling: "aplies" -> "applies"

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:59:58 +03:00
Brian Norris 1196ac5a99 mtd: nand: remove unnecessary variable
`writeops' is unnecessary in the function `nand_update_bbt()'

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:57:49 +03:00
Brian Norris afa17de262 mtd: nand: do not ignore all ECC errors
There are a few reasons not to ignore ECC errors here.

First, mtd->read_oob is being called in raw mode, so there should be no
error correction in the first place.

Second, if we change this such that there *is* error correction in this
function, then we will want to pass the error message upward.

In fact, the code I introduced to "ignore ECC errors" would have been
better if it had just placed this test down in `scan_block_full()' in
the first place. We would like to ignore ECC errors when we are simply
checking for bad block markers (e.g., factory marked), but we may not
want to ignore ECC errors when scanning OOB for a flash-based BBT
pattern (in `scan_read_raw()'; note that the return codes from
`scan_read_raw()' are not actually handled yet).

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:48:49 +03:00
Brian Norris 105513cc4a mtd: nand: refactor scanning code
A few pieces of code are unnecessarily duplicated. For easier
maintenance, we should fix this.

This should have no functional effect.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:48:47 +03:00
Brian Norris 0612b9ddc2 mtd: rename MTD_OOB_* to MTD_OPS_*
These modes are not necessarily for OOB only. Particularly, MTD_OOB_RAW
affected operations on in-band page data as well. To clarify these
options and to emphasize that their effect is applied per-operation, we
change the primary prefix to MTD_OPS_.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:28:59 +03:00
Brian Norris 289c052221 mtd: replace DEBUG() with pr_debug()
Start moving away from the MTD_DEBUG_LEVEL messages. The dynamic
debugging feature is a generic kernel feature that provides more
flexibility.

(See Documentation/dynamic-debug-howto.txt)

Also fix some punctuation, indentation, and capitalization that went
along with the affected lines.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:16 +03:00
Brian Norris d037021953 mtd: nand: style fixups in pr_* messages
This is a cleanup of some punctuation, indentation, and capitalization
on the lines affected affected by the last patch.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:15 +03:00
Brian Norris 9a4d4d6901 mtd: nand: convert printk() to pr_*()
Instead of directly calling printk, it's simpler to use the built-in
pr_* functions. This shortens code and allows easy customization through
the definition of a pr_fmt() macro (not used currently). Ideally, we
could implement much of this with dev_* functions, but the MTD subsystem
does not necessarily register all its master `mtd_info.dev` device, so
we cannot use dev_* consistently. See:
http://lists.infradead.org/pipermail/linux-mtd/2011-July/036950.html

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:15 +03:00
Brian Norris a0f5080ecc mtd: nand: change KERN_DEBUG to KERN_INFO
Soon we will change many printk statements into pr_* statements, i.e.,
'printk(KERN_INFO, ...)' becomes 'pr_info(...)'. However, this means that
KERN_DEBUG messages will become pr_debug() statements and therefore will
not be activated by default - they must be enabled using dynamic debug.
So, for important DEBUG messages, we will simply upgrade these to INFO
so that they appear by default.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:15 +03:00
Brian Norris 903cd06cd6 mtd: nand: ignore ECC errors for simple BBM scans
Now that nand_do_readoob() may return -EUCLEAN or -EBADMSG on ECC errors,
we need to handle the return value specially in some cases.

When scanning for simple bad block markers, reacting to an ECC error is
not very useful, as we assume that the relevant markers are still
non-0xFF for true bad blocks.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <dedekind1@gmail.com>
2011-09-11 15:02:14 +03:00
Brian Norris 7854d3f749 mtd: spelling, capitalization, uniformity
Therefor -> Therefore
[Intern], [Internal] -> [INTERN]
[REPLACABLE] -> [REPLACEABLE]
syndrom, syndom -> syndrome
ecc -> ECC
buswith -> buswidth
endianess -> endianness
dont -> don't
occures -> occurs
independend -> independent
wihin -> within
erease -> erase
blockes -> blocks
...

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:02:13 +03:00
Brian Norris 0870066d7e mtd: remove printk's for [kv][mz]alloc failures
When a memory allocation fails, the kernel will print out a backtrace
automatically. These print statements are unnecessary.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:02:05 +03:00
Brian Norris 8b6e50c9eb mtd: nand: multi-line comment style fixups
Artem: while on it, do other commentaries clean-ups:
1. Start one-line comments with capital letter and no dot at the end
2. Turn sparse multi-line comments into one-line comments
3. Change "phrase ?" to "phrase?" and the same with "!".
4. Remove tabs from the kerneldoc parameters comments - they are mixed
   with tabs often, and inconsistent.
5. Put dot at the end of descriptions in kerneldoc comments.
6. Some other small commentaries clean-ups

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:02:04 +03:00
Brian Norris 53d5d88850 mtd: nand: rename CREATE_EMPTY bbt flag with proper prefix
According to our new prefix rules, we should rename NAND_CREATE_EMPTY_BBT
with a NAND_BBT prefix, i.e., NAND_BBT_CREATE_EMPTY.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:01:56 +03:00
Brian Norris b8f8068405 mtd: nand: move NAND_CREATE_EMPTY_BBT flag
The NAND_CREATE_EMPTY_BBT flag was added by commit:
  453281a973
  mtd: nand: introduce NAND_CREATE_EMPTY_BBT
This flag is not used within the kernel and not explained well, so I
took the liberty to edit its comments.

Also, this is a BBT-related flag (and closely tied with NAND_BBT_CREATE)
so I'm moving it to bbm.h next to NAND_BBT_CREATE, thus requiring that
we use the flag in nand_chip.bbt_options, *not* in nand_chip.options.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:01:56 +03:00
Brian Norris bb9ebd4e71 mtd: nand: rename NAND_USE_FLASH_BBT
Recall the recently added prefix requirements:
 * "NAND_" for flags in nand.h, used in nand_chip.options
 * "NAND_BBT_" for flags in bbm.h, used in nand_chip.bbt_options
        or in nand_bbt_descr.options

Thus, I am changing NAND_USE_FLASH_BBT to NAND_BBT_USE_FLASH.

Again, this flag is found in bbm.h and so should NOT be used in the
"nand_chip.options" field.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:01:56 +03:00
Brian Norris a40f73419f mtd: nand: consolidate redundant flash-based BBT flags
This patch works with the following three flags from two headers (nand.h
and bbm.h):
  (1) NAND_USE_FLASH_BBT (nand.h)
  (2) NAND_USE_FLASH_BBT_NO_OOB (nand.h)
  (3) NAND_BBT_NO_OOB (bbm.h)

These flags are all related and interdependent, yet they were in
different headers. Flag (2) is simply the combination of (1) and (3) and
can be eliminated.

This patch accomplishes the following:
  * eliminate NAND_USE_FLASH_BBT_NO_OOB (i.e., flag (2))
  * move NAND_USE_FLASH_BBT (i.e., flag (1)) to bbm.h

It's important to note that because (1) and (3) are now both found in
bbm.h, they should NOT be used in the "nand_chip.options" field.

I removed a small section from the mtdnand DocBook because it referes to
NAND_USE_FLASH_BBT in nand.h, which has been moved to bbm.h.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:01:56 +03:00
Brian Norris 5fb1549dfc mtd: nand: separate chip options / bbt_options
This patch handles the problems we've been having with using conflicting
flags from nand.h and bbm.h in the same nand_chip.options field. We
should try to separate these two spaces a little more clearly, and so I
have added a bbt_options field to nand_chip.

Important notes about nand_chip fields:
* bbt_options field should contain ONLY flags from bbm.h. They should be
  able to pass safely to a nand_bbt_descr data structure.
    - BBT option flags start with the "NAND_BBT_" prefix.
* options field should contian ONLY flags from nand.h. Ideally, they
  should not be involved in any BBT related options.
    - NAND chip option flags start with the "NAND_" prefix.
* Every flag should have a nice comment explaining what the flag is. While
  this is not yet the case on all existing flags, please be sure to write
  one for new flags. Even better, you can help document the code better
  yourself!

Please try to follow these conventions to make everyone's lives easier.

Among the flags that are being moved to the new bbt_options field
throughout various drivers, etc. are:
 * NAND_BBT_SCANLASTPAGE
 * NAND_BBT_SCAN2NDPAGE
and there will be more to come.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:01:56 +03:00
Brian Norris a0dc552951 mtd: nand: remove NAND_BBT_SCANBYTE1AND6 option
This patch reverts most of:
    commit 58373ff0af
    mtd: nand: more BB Detection refactoring and dynamic scan options

According to the discussion at:
    http://lists.infradead.org/pipermail/linux-mtd/2011-May/035696.html
the NAND_BBT_SCANBYTE1AND6 flag, although technically valid, can break
some existing ECC layouts that use the 6th byte in the OOB for ECC data.
Furthermore, we apparently do not need to scan both bytes 1 and 6 in
the OOB region of the devices under consideration; instead, we only need
to scan one or the other.

Thus, the NAND_BBT_SCANBYTE1AND6 flag is at best unnecessary and at
worst a regression.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:01:46 +03:00
Brian Norris a2f812df0b mtd: nand: dynamic allocation of flash-based BBT structs
It is nicer to dynamically create our badblock patterns than to
statically define them. The nand_create_default_bbt_descr() function
does a sufficient job of handling various bad block scanning options
for either flash-based or non-flash-based BBTs, so we might as well
use the function for both cases.

This patch simplifies and shortens our code (and removes a TODO that
I left a few months ago).

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25 01:50:14 +01:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Stanislav Fomichev 7912a5e7f3 mtd: nand: fix pointer NULL pointer dereferencing
In 'verify_bbt_descr()', first check the "bd" pointer, then
dereference it.

Comments amended by Artem.

Signed-off-by: Stanislav Fomichev <kernel@fomichev.me>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:44 +00:00
Randy Dunlap 1534b8b097 mtd: fix nand kernel-doc warnings
Warning(include/linux/mtd/nand.h:543): No description found for parameter 'badblockbits'
Warning(drivers/mtd/nand/nand_bbt.c:1101): No description found for parameter 'mtd'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc:	David Woodhouse <dwmw2@infradead.org>
Cc:	linux-mtd@lists.infradead.org
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-12-03 16:31:24 +00:00
Sebastian Andrzej Siewior 453281a973 mtd: nand: introduce NAND_CREATE_EMPTY_BBT
it will create an empty BBT table without considering vendor's BBT
information. Vendor's information may be unavailable if the NAND
controller has a different DATA & OOB layout or this information may be
allready purged.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-25 00:54:37 +01:00
Sebastian Andrzej Siewior 7cba7b14fe mtd: nand: add support for BBT without OOB
The first (sixt) byte in the OOB area contains vendor's bad block
information. During identification of the NAND chip this information is
collected by scanning the complete chip.
The option NAND_USE_FLASH_BBT is used to store this information in a sector so
we don't have to scan the complete flash. Unfortunately the code stores
a marker in order to recognize the BBT in the OOB area. This will fail
if the OOB area is completely used for ECC.
This patch introduces the option NAND_USE_FLASH_BBT_NO_OOB which has to be
used with NAND_USE_FLASH_BBT. It will then store BBT on flash without
touching the OOB area. The BBT format on flash remains same except the
first page starts with the recognition pattern followed by the version byte.
This change was tested in nandsim and it looks good so far :)

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-25 00:53:48 +01:00