Commit graph

116 commits

Author SHA1 Message Date
Nicholas Mc Guire 0760e81864 mtd: nand: omap: drop condition with no effect
The if and the else branch code are identical - so the condition has no
effect on the effective code. This patch removes the condition and the
duplicated code and updates the documentation as suggested by
Roger Quadros <rogerq@ti.com>.

Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: Pekon Gupta <pekon@pek-sem.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-02-05 19:51:08 -08:00
Linus Torvalds d6666be6f0 MTD updates for 3.19:
* Add device tree support for DoC3
 
  * SPI NOR:
 
     Refactoring, for better layering between spi-nor.c and its driver users
     (e.g., m25p80.c)
 
     New flash device support
 
     Support 6-byte ID strings
 
  * NAND
 
     New NAND driver for Allwinner SoC's (sunxi)
 
     GPMI NAND: add support for raw (no ECC) access, for testing purposes
 
     Add ATO manufacturer ID
 
     A few odd driver fixes
 
  * MTD tests:
 
     Allow testers to compensate for OOB bitflips in oobtest
 
     Fix a torturetest regression
 
  * nandsim: Support longer ID byte strings
 
 And more.
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Merge tag 'for-linus-20141215' of git://git.infradead.org/linux-mtd

Pull MTD updates from Brian Norris:
 "Summary:
   - Add device tree support for DoC3

   - SPI NOR:
        Refactoring, for better layering between spi-nor.c and its
        driver users (e.g., m25p80.c)

        New flash device support

        Support 6-byte ID strings

   - NAND:
        New NAND driver for Allwinner SoC's (sunxi)

        GPMI NAND: add support for raw (no ECC) access, for testing
        purposes

        Add ATO manufacturer ID

        A few odd driver fixes

   - MTD tests:
        Allow testers to compensate for OOB bitflips in oobtest

        Fix a torturetest regression

   - nandsim: Support longer ID byte strings

  And more"

* tag 'for-linus-20141215' of git://git.infradead.org/linux-mtd: (63 commits)
  mtd: tests: abort torturetest on erase errors
  mtd: physmap_of: fix potential NULL dereference
  mtd: spi-nor: allow NULL as chip name and try to auto detect it
  mtd: nand: gpmi: add raw oob access functions
  mtd: nand: gpmi: add proper raw access support
  mtd: nand: gpmi: add gpmi_copy_bits function
  mtd: spi-nor: factor out write_enable() for erase commands
  mtd: spi-nor: add support for s25fl128s
  mtd: spi-nor: remove the jedec_id/ext_id
  mtd: spi-nor: add id/id_len for flash_info{}
  mtd: nand: correct the comment of function nand_block_isreserved()
  jffs2: Drop bogus if in comment
  mtd: atmel_nand: replace memcpy32_toio/memcpy32_fromio with memcpy
  mtd: cafe_nand: drop duplicate .write_page implementation
  mtd: m25p80: Add support for serial flash Spansion S25FL132K
  MTD: m25p80: fix inconsistency in m25p_ids compared to spi_nor_ids
  mtd: spi-nor: improve wait-till-ready timeout loop
  mtd: delete unnecessary checks before two function calls
  mtd: nand: omap: Fix NAND enumeration on 3430 LDP
  mtd: nand: add ATO manufacturer info
  ...
2014-12-17 09:59:26 -08:00
Roger Quadros 775a9134f4 mtd: nand: omap: Fix NAND enumeration on 3430 LDP
3430LDP has NAND flash with 32 bytes OOB size which is sufficient to hold
BCH8 codes but the small page check introduced in
commit b491da7233 ("mtd: nand: omap: clean-up ecc layout for BCH ecc schemes")
considers anything below 64 bytes unsuitable for BCH4/8/16. There is another
bug in that code where it doesn't skip the check for OMAP_ECC_HAM1_CODE_SW.

Get rid of that small page check code as it is insufficient and redundant
because we are checking for OOB available bytes vs ecc layout before calling
nand_scan_tail().

Fixes: b491da7233 ("mtd: nand: omap: clean-up ecc layout for BCH ecc schemes")

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-11-25 22:44:10 -08:00
Rostislav Lisovy 1dc338e856 mtd: nand: omap: Synchronize the access to the ECC engine
The AM335x Technical Reference Manual (spruh73j.pdf) says
"Because the ECC engine includes only one accumulation context,
it can be allocated to only one chip-select at a time ... "
(7.1.3.3.12.3). Since the commit 97a288ba2c ("ARM: omap2+:
gpmc-nand: Use dynamic platform_device_alloc()") gpmc-nand
driver supports multiple NAND flash devices connected to
the single controller.
Use global 'struct nand_hw_control' among multiple NAND
instances to synchronize the access to the single ECC Engine.

Tested with custom AM335x board using 2x NAND flash chips.

Signed-off-by: Rostislav Lisovy <lisovy@merica.cz>
Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-11-05 13:01:22 -08:00
Rostislav Lisovy 94cb4ee0f7 mtd: nand: omap: Do not use global variables
Since the commit 97a288ba2c ("ARM: omap2+: gpmc-nand: Use
dynamic platform_device_alloc()") gpmc-nand driver supports
multiple NAND flash devices connected to the single controller.
Remove global variable to make the code thread-safe.

Signed-off-by: Rostislav Lisovy <lisovy@merica.cz>
Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-10-22 01:33:33 -07:00
Wolfram Sang 5cfb36ebf4 mtd: nand: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:58 +02:00
Ezequiel García d2f08c7521 nand: omap2: Replace pr_err with dev_err
Usage of pr_err is frowned upon, so replace it with dev_err.

Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-09-22 11:38:18 -07:00
Ezequiel García 93af53b863 nand: omap2: Remove horrible ifdefs to fix module probe
The current code abuses ifdefs to determine if the selected ECC scheme
is supported by the running kernel. As a result the code is hard to read,
and it also fails to load as a module.

This commit removes all the ifdefs and instead introduces a function
omap2_nand_ecc_check() to check if the ECC is supported by using
IS_ENABLED(CONFIG_xxx).

Since IS_ENABLED() is true when a config is =y or =m, this change fixes the
module so it can be loaded with no issues.

Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-09-22 11:37:51 -07:00
Ezequiel García fef775caa7 nand: omap2: Add support for flash-based bad block table
This commit adds a new platform-data boolean property that enables use
of a flash-based bad block table. This can also be enabled by setting
the 'nand-on-flash-bbt' devicetree property.

If the flash BBT is not enabled, the driver falls back to use OOB
bad block markers only, as before. If the flash BBT is enabled the
kernel will keep track of bad blocks using a BBT, in addition to
the OOB markers.

As explained by Brian Norris the reasons for using a BBT are:

""
The primary reason would be that NAND datasheets specify it these days.
A better argument is that nobody guarantees that you can write a
bad block marker to a worn out block; you may just get program failures.

This has been acknowledged by several developers over the last several
years.

Additionally, you get a boot-time performance improvement if you only
have to read a few pages, instead of a page or two from every block on
the flash.
""

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-09-17 01:02:48 -07:00
Roger Quadros 40ddbf5069 mtd: nand: omap: Fix 1-bit Hamming code scheme, omap_calculate_ecc()
commit 65b97cf6b8 introduced in v3.7 caused a regression
by using a reversed CS_MASK thus causing omap_calculate_ecc to
always fail. As the NAND base driver never checks for .calculate()'s
return value, the zeroed ECC values are used as is without showing
any error to the user. However, this won't work and the NAND device
won't be guarded by any error code.

Fix the issue by using the correct mask.

Code was tested on omap3beagle using the following procedure
- flash the primary bootloader (MLO) from the kernel to the first
NAND partition using nandwrite.
- boot the board from NAND. This utilizes OMAP ROM loader that
relies on 1-bit Hamming code ECC.

Fixes: 65b97cf6b8 (mtd: nand: omap2: handle nand on gpmc)

Cc: <stable@vger.kernel.org>	[3.7+]
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2014-08-25 16:15:33 -07:00
Roger Quadros 7d5929c1f3 mtd: nand: omap: Revert to using software ECC by default
For v3.12 and prior, 1-bit Hamming code ECC via software was the
default choice. Commit c66d039197 in v3.13 changed the behaviour
to use 1-bit Hamming code via Hardware using a different ECC layout
i.e. (ROM code layout) than what is used by software ECC.

This ECC layout change causes NAND filesystems created in v3.12
and prior to be unusable in v3.13 and later. So revert back to
using software ECC by default if an ECC scheme is not explicitely
specified.

This defect can be observed on the following boards during legacy boot

-omap3beagle
-omap3touchbook
-overo
-am3517crane
-devkit8000
-ldp
-3430sdp

Signed-off-by: Roger Quadros <rogerq@ti.com>
Tested-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2014-08-25 16:15:32 -07:00
Ted Juan 2913aae5f9 mtd: nand: omap: fix omap_calculate_ecc_bch() for-loop error
Fixes:  2c9f2365d1
 mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch4 in omap_calculate_ecc_bch

 Fixes: 7bcd1dca1d
 mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch8 in omap_calculate_ecc_bch

Cc: <stable@vger.kernel.org> # 3.13.x+
Signed-off-by: Ted Juan <ted.juan@gmail.com>
Acked-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-05-28 13:13:00 -07:00
pekon gupta 9748fff964 mtd: nand: omap: add support for BCH16_ECC - NAND driver updates
This patch add support for BCH16 ecc-scheme in OMAP NAND driver, by extending
following functions:
 - omap_enable_hwecc (nand_chip->ecc.hwctl): configure GPMC controller
 - omap_calculate_ecc_bch (nand_chip->ecc.calculate): fetch ECC signature from GPMC controller
 - omap_elm_correct_data (nand_chip->ecc.correct): detect and correct ECC errors using ELM

(a) BCH16 ecc-scheme can detect and correct 16 bit-flips per 512Bytes of data.
(b) BCH16 ecc-scheme generates 26-bytes of ECC syndrome / 512B.
Due to (b) this scheme can only be used with NAND devices which have enough
OOB to satisfy the relation: "OOBsize per page >= 26 * (page-size / 512)"

Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-05-20 17:52:15 -07:00
pekon gupta f306e8c3b6 mtd: nand: omap: fix BCHx ecc.correct to return detected bit-flips in erased-page
fixes: commit 62116e5171
       mtd: nand: omap2: Support for hardware BCH error correction.

In omap_elm_correct_data(), if bitflip_count in an erased-page is within the
correctable limit (< ecc.strength), then it is not indicated back to the caller
ecc->read_page().

This mis-guides upper layers like MTD and UBIFS layer to assume erased-page as
perfectly clean and use it for writing even if actual bitflip_count was
dangerously high (bitflip_count > mtd->bitflip_threshold).

This patch fixes this above issue, by returning 'stats' to caller
ecc->read_page() under all scenarios.

Reported-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Cc: <stable@vger.kernel.org> # 3.9.x+
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-05-20 16:32:17 -07:00
Christian Engelmayer 9fd6c6c18c mtd: nand: omap: fix compile warning on ‘erased_sector_bitflips’
Commit 2c9f2365 (mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch4
in omap_calculate_ecc_bch) introduced minor compile warning
"‘erased_sector_bitflips’ defined but not used [-Wunused-function]" when
compiling without CONFIG_MTD_NAND_OMAP_BCH. Move function
erased_sector_bitflips() into the same ifdef section as the only caller.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-04-15 23:20:30 -07:00
Jingoo Han 00d09891eb mtd: omap2: Use devm_ioremap_resource()
Use devm_ioremap_resource() in order to make the code simpler,
and remove redundant return value check of platform_get_resource()
because the value is checked by devm_ioremap_resource(). Also,
'unsigned long mem_size' is removed from 'struct omap_nand_info',
because the 'mem_size' variable is not necessary anymore.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-25 23:21:15 -07:00
Pekon Gupta 3f4eb14bdb mtd: devices: elm: check for hardware engine's design constraints
ELM hardware engine is used by BCH ecc-schemes for detecting and locating ECC
errors. This patch adds the following checks for ELM hardware engine:

 - ELM internal buffers are of 1K,
   so it cannot process data with ecc-step-size > 1K.

 - ELM engine can execute upto maximum of 8 threads in parallel,
   so in *page-mode* (when complete page is processed in single iteration),
   ELM cannot support ecc-steps > 8.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-25 23:08:52 -07:00
Pekon Gupta c7b05e9701 mtd: nand: omap: remove is_elm_present flag
'is_elm_present' flag is not used anywhere. This check is implicitely
taken care while selecting appropriate ecc-scheme via DT or board-file.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:55:28 -07:00
Pekon Gupta 16e69322c5 mtd: nand: omap: ecc.hwctl: clean omap_enable_hwecc_bch for redundant ECC configs
This patch
 - refactors GPMC configurations based on ecc-scheme
 - removed dependency on is_elm_present() flag, which is implicitely
   taken care by selecting appropriate ecc-scheme

Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:55:28 -07:00
Pekon Gupta c5957a3201 mtd: nand: omap: ecc.hwctl: refactor omap_enable_hwecc_bch for ECC related GPMC configs
Lots of if..then..else conditions in omap_enable_hwecc_bch() can be avoided if
code is refactored based on ecc-scheme.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:55:27 -07:00
Pekon Gupta 7c977c3eb2 mtd: nand: omap: ecc.hwctl: rename omap3_enable_hwecc_bch to omap_enable_hwecc_bch
This patch
 - renames omap3_enable_hwecc_bch -> omap_enable_hwecc_bch to keep
   nomenclature independent of any device family.
 - using '__maybe_unused' instead of `ifdef based conditional compilation
   to suppress warning for un-used functions

Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:55:27 -07:00
Pekon Gupta 7bcd1dca1d mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch8 in omap_calculate_ecc_bch
merge omap3_calculate_ecc_bch8() into omap_calculate_ecc_bch() so that
common callback can be used for both OMAP_ECC_BCH8_CODE_HW and
OMAP_ECC_BCH8_CODE_HW_DETECTION_SW
+---------------------+-------------------------------------------------------+
|ecc-scheme           | nand_chip->calculate() after this patch               |
+---------------------+-------------------------------------------------------+
|HAM1_ECC             | omap_calculate_ecc()                                  |
+---------------------+-------------------------------------------------------+
|BCH4_HW_DETECTION_SW | omap_calculate_ecc_bch()                              |
|BCH4_HW              | omap_calculate_ecc_bch()                              |
|BCH8_HW_DETECTION_SW | omap3_calculate_ecc_bch8() -> omap_calculate_ecc_bch()|
|BCH8_HW              | omap_calculate_ecc_bch()                              |
+---------------------+-------------------------------------------------------+

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:30:27 -07:00
Pekon Gupta 2c9f2365d1 mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch4 in omap_calculate_ecc_bch
merges omap3_calculate_ecc_bch4() into omap_calculate_ecc_bch() so that
common callback can be used for both OMAP_ECC_BCH4_CODE_HW and
OMAP_ECC_BCH4_CODE_HW_DETECTION_SW ecc-schemes

+---------------------+-------------------------------------------------------+
|ecc-scheme           | nand_chip->calculate() after this patch               |
+---------------------+-------------------------------------------------------+
|HAM1_ECC             | omap_calculate_ecc()                                  |
+---------------------+-------------------------------------------------------+
|BCH4_HW_DETECTION_SW | omap3_calculate_ecc_bch4() -> omap_calculate_ecc_bch()|
|BCH4_HW              | omap_calculate_ecc_bch()                              |
|BCH8_HW_DETECTION_SW | omap3_calculate_ecc_bch8()                            |
|BCH8_HW              | omap_calculate_ecc_bch()                              |
+---------------------+-------------------------------------------------------+

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:30:27 -07:00
Pekon Gupta f5dc06fb71 mtd: nand: omap: ecc.calculate: refactor omap_calculate_ecc_bch for BCHx_HW ecc-scheme
OMAP NAND driver supports multiple flavours of BCH4 and BCH8 ECC algorithms.
+------+------------------------------------+---------------+---------------+
| Algo | ECC scheme                         |ECC calculation|Error detection|
+------+------------------------------------+---------------+---------------+
|      |OMAP_ECC_BCH4_CODE_HW_DETECTION_SW  |H/W (GPMC)     |S/W            |
| BCH4 |OMAP_ECC_BCH4_CODE_HW               |H/W (GPMC)     |H/W (ELM)      |
+------+------------------------------------+---------------+---------------+
|      |OMAP_ECC_BCH8_CODE_HW_DETECTION_SW  |H/W (GPMC)     |S/W            |
| BCH8 |OMAP_ECC_BCH8_CODE_HW               |H/W (GPMC)     |H/W (ELM)      |
+------+------------------------------------+---------------+---------------+

This patch refactors omap_calculate_ecc_bch() so that
 - separate out ecc-scheme specific code so that common-code can be reused
   between different implementations of same ECC algorithm.
 - new ecc-schemes can be added with ease in future.

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:30:27 -07:00
Pekon Gupta a4c7ca004d mtd: nand: omap: ecc.calculate: rename omap3_calculate_ecc_bch to omap_calculate_ecc_bch
rename omap3_calculate_ecc_bch -> omap_calculate_ecc_bch to
keep nomenclature independent of any device family.

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 02:30:26 -07:00
Pekon Gupta 13fbe0641e mtd: nand: omap: ecc.correct: omap_elm_correct_data: fix programmed-page bit-flip correction logic
This patch updates following checks when bit-flips are detected by ELM:

 - Do not evaluate bit-flips when un-correctable bit-flips is reported by ELM,
   because as per [1] when ELM reports an un-correctable bit-flips,
   'number of error' field in its ELM_LOCATION_STATUS register is also invalid.

 - Return with error-code '-EBADMSG' on detection of un-correctable bit-flip.

 - Return with error-code '-EBADMSG' when bit-flips position is outside current
   Sector and OOB area.

[1] ELM IP spec Table-25 ELM_LOCATION_STATUS Register.
    ELM_LOCATION_STATUS[8] = ECC_CORRECTABLE: Error location process exit status
        0x0: ECC error location process failed.
             Number of errors and error locations are invalid.
        0x1: all errors were successfully located.
             Number of errors and error locations are valid.

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 01:47:59 -07:00
Pekon Gupta b08e1f632c mtd: nand: omap: ecc.correct: omap_elm_correct_data: cleanup for future enhancements
Current omap_elm_correct_data() code is not scalable for future ecc-schemes
due to presence of tweaks and hard-coded macros for BCH4_ECC and BCH8_ECC
ecc-schemes at multiple places.

This patch:
 - replaces 'ecc_opt' with '(info->nand.ecc.strength == BCH8_MAX_ERROR)
   used to differentiate between BCH8_HW and BCH4_SW
 - replaces macros (defining magic number for specific ecc-scheme) with
   generic variables
 - removes dependency on macros defined in elm.h (like BCHx_ECC_OOB_BYTES)

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 01:47:59 -07:00
Pekon Gupta 78f43c5383 mtd: nand: omap: ecc.correct: omap_elm_correct_data: fix erased-page detection for BCHx_HW ECC schemes
As erased-pages do not have ECC stored in their OOB area, so they need to be
seperated out from programmed-pages, before doing BCH ECC correction.

In current implementation of omap_elm_correct_data() which does ECC correction
for BCHx ECC schemes, this erased-pages are detected based on specific marker
byte (reserved as 0x00) in ecc-layout.
However, this approach has some limitation like;
 1) All ecc-scheme layouts do not have such Reserved byte marker to
    differentiate between erased-page v/s programmed-page. Thus this is a
    customized solution.
 2) Reserved marker byte can itself be subjected to bit-flips causing
    erased-page to be misunderstood as programmed-page.

This patch removes dependency on any marker byte in ecc-layout, instead it
compares calc_ecc[] with pattern of ECC-of-all(0xff). This implicitely
means that both 'data + oob == all(0xff).

Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 01:47:59 -07:00
Pekon Gupta de0a4d69e6 mtd: nand: omap: ecc.correct: omap_elm_correct_data: rename ambiguous variable 'eccsize' and 'ecc_vector_size'
renaming following variables as they cause confusion due to resemblence to
another similar field in 'struct nand_ecc_ctrl' (nand_chip->ecc.size).
renaming: ecc_vector_size --> ecc->bytes	(info->nand.ecc.bytes)
renaming: eccsize         --> actual_eccbytes	(info->nand.ecc.bytes - 1) for BCH4 and BCH8

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 01:47:59 -07:00
Pekon Gupta 4e558072ef mtd: nand: omap: add field to indicate current ecc-scheme in 'struct omap_nand_info'
Information of currently selected ECC scheme 'enum omap_ecc ecc_opt' should
available outside platform-data, so that single nand_chip->ecc callback can
support multiple ecc-scheme configurations.

Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-20 01:47:59 -07:00
Pekon Gupta bb38eefb68 mtd: nand: omap: fix ecclayout->oobfree->length
This patch excludes reserved-marker byte-position from oobfree->length
calculation. Thus all bytes from oobfree->offset till end of OOB are free.

CC: <stable@vger.kernel.org> # 3.13.x+
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-02-23 14:49:57 -08:00
Pekon Gupta aa6092f983 mtd: nand: omap: fix ecclayout->oobfree->offset
1) In current implementation, ecclayout->oobfree->offset is calculated with
 respect to ecclayout->eccpos[0] which is incorrect because ECC bytes may not
 be stored contiguously in OOB.
 So, this patch calculates ecclayout->oobfree->offset with respect to last
 ECC byte-position 'eccpos[ecclayout->eccbytes-1]'.

2) ECC layout of some ecc-schemes expects reserved-markers at specific eccpos[]
 which should not be over-written by any file-system metadata.
 So this patch aligns oobfree->offset taking into account of such markers.

CC: <stable@vger.kernel.org> # 3.13.x+
Tested-by: Enric Balletbo i Serra <eballetbo@gmail.com>
Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-02-23 14:49:57 -08:00
Pekon Gupta eae39cb493 mtd: nand: omap: fix ecclayout to be in sync with u-boot NAND driver
Fixes: commit a919e51161
       mtd: nand: omap2: clean-up BCHx_HW and BCHx_SW ECC configurations in device_probe

Fixes ecclayout mismatch introduced in above commit for following ecc-schemes:
 - OMAP_ECC_BCH4_CODE_HW_DETECTION_SW
 - OMAP_ECC_BCH8_CODE_HW_DETECTION_SW
 However, this patch also touches other ecc-schemes as the fix required
 refactoring common code, into ecc-scheme specific code.

This patch aligns ecc-layout for below ecc-schemes as per reference [1],[2],[3]

 +---+------------+-------------++-------------+-------------+
 |OOB|BCH8_CODE_HW|BCH8_CODE_HW_||HAM1_CODE_HW |HAM1_CODE_HW |
 |pos|            | DETECTION_SW||(x8 device)  |(x16 device) |
 +---+------------+-------------++-------------+-------------+
 | 0 |BADBLK_MARK | BADBLK_MARK || BADBLK_MARK | BADBLK_MARK |
 | 1 |BADBLK_MARK | BADBLK_MARK || eccpos[0]   | BADBLK_MARK |
 | 2 | eccpos[0]  | eccpos[0]   || eccpos[1]   | eccpos[0]   |
 | 3 | eccpos[1]  | eccpos[1]   || eccpos[2]   | eccpos[1]   |
 | 4 | eccpos[2]  | eccpos[2]   || eccpos[3]   | eccpos[2]   |
 | 5 | eccpos[3]  | eccpos[3]   || eccpos[4]   | eccpos[3]   |
 | 6 | eccpos[4]  | eccpos[4]   || eccpos[5]   | eccpos[4]   |
 | 7 | eccpos[5]  | eccpos[5]   || eccpos[6]   | eccpos[5]   |
 | 8 | eccpos[6]  | eccpos[6]   || eccpos[7]   | eccpos[6]   |
 | 9 | eccpos[7]  | eccpos[7]   || eccpos[8]   | eccpos[7]   |
 |10 | eccpos[8]  | eccpos[8]   || eccpos[9]   | eccpos[8]   |
 |11 | eccpos[9]  | eccpos[9]   || eccpos[10]  | eccpos[9]   |
 |12 | eccpos[10] | eccpos[10]  || eccpos[11]  | eccpos[10]  |
 |13 | eccpos[11] | eccpos[11]  || oobfree[0]  | eccpos[11]  |
 |14 | eccpos[12] | eccpos[12]  || oobfree[1]  | oobfree[0]  |
 |15 | eccpos[13] | <reserved>  || oobfree[2]  | oobfree[1]  |
 +---+------------+-------------++-------------+-------------+
 |16 | eccpos[14] | eccpos[13]  || oobfree[3]  | oobfree[2]  |
 |...| [...]      | [...]       || [...]       | [...]       |
 |56 | eccpos[54] | eccpos[51]  || oobfree[43] | oobfree[42] |
 |57 | eccpos[55] | <reserved>  || oobfree[44] | oobfree[43] |
 +===+============+=============+==============+=============+
 |58 | oobfree[0] | oobfree[0]  || oobfree[45] | oobfree[44] |
 |59 | oobfree[1] | oobfree[1]  || oobfree[46] | oobfree[45] |
 |60 | oobfree[2] | oobfree[2]  || oobfree[47] | oobfree[46] |
 |61 | oobfree[3] | oobfree[3]  || oobfree[48] | oobfree[47] |
 |62 | oobfree[4] | oobfree[4]  || oobfree[49] | oobfree[48] |
 |63 | oobfree[5] | oobfree[5]  || oobfree[50] | oobfree[49] |
 +---+------------+-------------+--------------+-------------+

[1] ecc-layout expected by ROM code, as specified in SoC TRM under:
      Chapter="Initialization"
        Section="Device Initialization by ROM code"
            Sub-Section="Memory Booting"
                Heading="NAND"
                Figure="ECC Locations in NAND Spare Areas"

[2] ecc-layout updates in u-boot
    http://lists.denx.de/pipermail/u-boot/2013-November/167551.html

[3] u-boot configurations to match above ecc-layout are documented at
    https://processors.wiki.ti.com/index.php/Linux_Core_NAND_User%27s_Guide

CC: <stable@vger.kernel.org> # 3.13.x+
Reported-by: Enric Balletbo Serra <eballetbo@iseebcn.com>
Tested-by: Enric Balletbo i Serra <eballetbo@gmail.com>
Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-02-23 14:49:56 -08:00
Brian Norris cf0e4d2b3f mtd: omap2: use nand_base defaults for polled I/O
The omap_{read,write}_buf{8,16}() functions are identical to the default
nand_base versions. Just let nand_base assign them in the
NAND_OMAP_POLLED case.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Pekon Gupta <pekon@ti.com>
2014-01-07 10:07:35 -08:00
Wei Yongjun 9211439b8a mtd: nand: omap: fix error return code in omap_nand_probe()
Fix to return a negative error code from the error handling case instead
of 0, to more closely match the rest of this function.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Acked-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:15 -08:00
Pekon Gupta 70ba6d71dd mtd: nand: omap: updated devm_xx for all resource allocation and free calls
"Managed Device Resource" or devm_xx calls takes care of automatic freeing
of the resource in case of:
- failure during driver probe
- failure during resource allocation
- detaching or unloading of driver module (rmmod)
Reference: Documentation/driver-model/devres.txt

Though OMAP NAND driver handles freeing of resource allocation in most of
the cases, but using devm_xx provides more clean and effortless approach
to handle all such cases.

- simplifies label for exiting probe during error
  s/out_release_mem_region/return_error

Signed-off-by: Pekon Gupta <pekon@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:11 -08:00
Pekon Gupta 32d42a855a mtd: nand: omap: use drivers/mtd/nand/nand_bch.c wrapper for BCH ECC instead of lib/bch.c
generic frame-work in mtd/nand/nand_bch.c is a wrapper above lib/bch.h which
encapsulates all control information specific to BCH ecc algorithm in software.
Thus this patch:
(1) replace omap specific implementations with equivalent wrapper in nand_bch.c
    so that generic code from nand_bch.c is re-used. like;
        omap3_correct_data_bch() -> nand_bch_correct_data()
        omap3_free_bch() -> nand_bch_free()
(2) replace direct calls to lib/bch.c with wrapper functions defined in nand_bch.c
	init_bch() -> nand_bch_init()

Signed-off-by: Pekon Gupta <pekon@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:10 -08:00
Pekon Gupta b491da7233 mtd: nand: omap: clean-up ecc layout for BCH ecc schemes
In current implementation omap3_init_bch_tail() is a common function to
define ecc layout for different BCHx ecc schemes.This patch:
(1) removes omap3_init_bch_tail() and defines ecc layout for individual
    ecc-schemes along with populating their nand_chip->ecc data in
    omap_nand_probe(). This improves the readability and scalability of
    code for add new ecc schemes in future.
(2) removes 'struct nand_bbt_descr bb_descrip_flashbased' because default
    nand_bbt_descr in nand_bbt.c matches the same (.len=1 for x8 devices).
(3) add the check to see if NAND device has enough OOB/Spare bytes to
    store ECC signature of whole page, as defined by ecc-scheme.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:10 -08:00
Pekon Gupta a919e51161 mtd: nand: omap2: clean-up BCHx_HW and BCHx_SW ECC configurations in device_probe
current implementation in omap3_init_bch() has some redundant code like:
(1) omap3_init_bch() re-probes the DT-binding to detect presence of ELM h/w
    engine on SoC. And based on that it selects implemetation of ecc-scheme.
    However, this is already done as part of GPMC DT parsing.
(2) As omap3_init_bch() serves as common function for configuring all types of
    BCHx ecc-schemes, so there are multiple levels of redudant if..then..else
    checks while populating nand_chip->ecc.

This patch make following changes to OMAP NAND driver:
(1) removes omap3_init_bch(): each ecc-scheme is individually configured in
    omap_nand_probe() there by removing redundant if..then..else checks.
(2) adds is_elm_present(): re-probing of ELM device via DT is not required as
    it's done in GPMC driver probe. Thus is_elm_present() just initializes ELM
    driver with NAND probe data, when ecc-scheme with h/w based error-detection
    is used.
(3) separates out configuration of different flavours of "BCH4" and "BCH8"
    ecc-schemes as given in below table
(4) conditionally compiles callbacks implementations of ecc.hwctl(),
    ecc.calculate(), ecc.correct() to avoid warning of un-used functions.

+---------------------------------------+---------------+---------------+
| ECC scheme                            |ECC calculation|Error detection|
+---------------------------------------+---------------+---------------+
|OMAP_ECC_HAM1_CODE_HW                  |H/W (GPMC)     |S/W            |
+---------------------------------------+---------------+---------------+
|OMAP_ECC_BCH4_CODE_HW_DETECTION_SW     |H/W (GPMC)     |S/W (lib/bch.c)|
| (needs CONFIG_MTD_NAND_ECC_BCH)       |               |               |
|                                       |               |               |
|OMAP_ECC_BCH4_CODE_HW                  |H/W (GPMC)     |H/W (ELM)      |
| (needs CONFIG_MTD_NAND_OMAP_BCH &&    |               |               |
|        ti,elm-id)                     |               |               |
+---------------------------------------+---------------+---------------+
|OMAP_ECC_BCH8_CODE_HW_DETECTION_SW     |H/W (GPMC)     |S/W (lib/bch.c)|
| (needs CONFIG_MTD_NAND_ECC_BCH)       |               |               |
|                                       |               |               |
|OMAP_ECC_BCH8_CODE_HW                  |H/W (GPMC)     |H/W (ELM)      |
| (needs CONFIG_MTD_NAND_OMAP_BCH &&    |               |               |
|        ti,elm-id)                     |               |               |
+---------------------------------------+---------------+---------------+

- 'CONFIG_MTD_NAND_ECC_BCH' is generic KConfig required to build lib/bch.c
    which is required for ECC error detection done in software.
    (mainly used for legacy platforms which do not have on-chip ELM engine)

- 'CONFIG_MTD_NAND_OMAP_BCH' is OMAP specific Kconfig to detemine presence
    on ELM h/w engine on SoC.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:09 -08:00
Pekon Gupta f18befb57b mtd: nand: omap: use DT specified bus-width only for scanning NAND device
This patch:
- calls nand_scan_ident() using bus-width as passed by DT
- removes double calls to nand_scan_ident(), in case first call fails
  then omap_nand_probe just returns error.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:08 -08:00
Pekon Gupta 633deb58e1 mtd: nand: omap: cleanup: replace local references with generic framework names
This patch updates following in omap_nand_probe() and omap_nand_remove()
- replaces "info->nand" with "nand_chip" (struct nand_chip *nand_chip)
- replaces "info->mtd" with "mtd" (struct mtd_info *mtd)
- white-space and formatting cleanup

Signed-off-by: Pekon Gupta <pekon@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:08 -08:00
Pekon Gupta c66d039197 mtd: nand: omap: combine different flavours of 1-bit hamming ecc schemes
OMAP NAND driver currently supports multiple flavours of 1-bit Hamming
ecc-scheme, like:
- OMAP_ECC_HAMMING_CODE_DEFAULT
	1-bit hamming ecc code using software library
- OMAP_ECC_HAMMING_CODE_HW
	1-bit hamming ecc-code using GPMC h/w engine
- OMAP_ECC_HAMMING_CODE_HW_ROMCODE
	1-bit hamming ecc-code using GPMC h/w engin with ecc-layout compatible
	to ROM code.

This patch combines above multiple ecc-schemes into single implementation:
- OMAP_ECC_HAM1_CODE_HW
	1-bit hamming ecc-code using GPMC h/w engine with ROM-code compatible
	ecc-layout.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:07 -08:00
Jingoo Han 453810b795 mtd: nand: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 21:34:33 +01:00
Brian Norris dad2256269 mtd: nand: remove NAND_BBT_SCANEMPTY
NAND_BBT_SCANEMPTY is a strange, badly-supported option with omap as its
single remaining user.

NAND_BBT_SCANEMPTY was likely used by accident in omap2[1]. And anyway,
omap2 doesn't scan the chip for bad blocks (courtesy of
NAND_SKIP_BBTSCAN), and so its use of this option is irrelevant.

This patch drops the NAND_BBT_SCANEMPTY option.

[1] http://lists.infradead.org/pipermail/linux-mtd/2012-July/042902.html

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Ivan Djelic <ivan.djelic@parrot.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 16:48:37 +01:00
Jingoo Han c15640081b mtd: nand: omap2: remove unnecessary platform_set_drvdata()
The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d06310
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-05 20:59:13 +01:00
Toan Pham 4ff6772b5b mtd: omap2: use msecs_to_jiffies()
Fix mtd-utils from returning -EIO. Formatting jffs2 filesystem was impossible
when CONFIG_HZ was set to a low value.

Signed-off-by: Toan Pham <tpham3783@gmail.com>
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>
2013-04-05 13:22:30 +01:00
Daniel Mack ad2457894c mtd: devices: elm: check for device's presence before configuration
In case the driver is not probed - due to config mismatches or errors
in the DTS files - dev_get_drvdata() returns NULL, leading to an Ooops
during boot.

Make elm_config() return an error in such cases to propagate the error
up to the user, so it can fall back to software mode.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-04-05 12:57:18 +01:00
Linus Torvalds 48476df998 Fairly unexciting MTD merge for 3.9:
* misc clean-ups in the MTD command-line partitioning parser (cmdlinepart)
  * add flash locking support for STmicro chips serial flash chips, as well as
    for CFI command set 2 chips.
  * new driver for the ELM error correction HW module found in various TI chips,
    enable the OMAP NAND driver to use the ELM HW error correction
  * added number of new serial flash IDs
  * various fixes and improvements in the gpmi NAND driver
  * bcm47xx NAND driver improvements
  * make the mtdpart module actually removable
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Merge tag 'for-linus-20130301' of git://git.infradead.org/linux-mtd

Pull MTD update from David Woodhouse:
 "Fairly unexciting MTD merge for 3.9:

   - misc clean-ups in the MTD command-line partitioning parser
     (cmdlinepart)
   - add flash locking support for STmicro chips serial flash chips, as
     well as for CFI command set 2 chips.
   - new driver for the ELM error correction HW module found in various
     TI chips, enable the OMAP NAND driver to use the ELM HW error
     correction
   - added number of new serial flash IDs
   - various fixes and improvements in the gpmi NAND driver
   - bcm47xx NAND driver improvements
   - make the mtdpart module actually removable"

* tag 'for-linus-20130301' of git://git.infradead.org/linux-mtd: (45 commits)
  mtd: map: BUG() in non handled cases
  mtd: bcm47xxnflash: use pr_fmt for module prefix in messages
  mtd: davinci_nand: Use managed resources
  mtd: mtd_torturetest can cause stack overflows
  mtd: physmap_of: Convert device allocation to managed devm_kzalloc()
  mtd: at91: atmel_nand: for PMECC, add code to check the ONFI parameter ECC requirement.
  mtd: atmel_nand: make pmecc-cap, pmecc-sector-size in dts is optional.
  mtd: atmel_nand: avoid to report an error when lookup table offset is 0.
  mtd: bcm47xxsflash: adjust names of bus-specific functions
  mtd: bcm47xxpart: improve probing of nvram partition
  mtd: bcm47xxpart: add support for other erase sizes
  mtd: bcm47xxnflash: register this as normal driver
  mtd: bcm47xxnflash: fix message
  mtd: bcm47xxsflash: register this as normal driver
  mtd: bcm47xxsflash: write number of written bytes
  mtd: gpmi: add sanity check for the ECC
  mtd: gpmi: set the Golois Field bit for mx6q's BCH
  mtd: devices: elm: Removes <xx> literals in elm DT node
  mtd: gpmi: fix a dereferencing freed memory error
  mtd: fix the wrong timeo for panic_nand_wait()
  ...
2013-03-02 16:33:54 -08:00
Philip Avinash 62116e5171 mtd: nand: omap2: Support for hardware BCH error correction.
ELM module can be used for hardware error correction of BCH 4 & 8 bit.
ELM module functionality is verified by checking the availability of
handle for ELM module in device tree. Hence supporting
1. ELM module available, BCH error correction done by ELM module. Also
support read & write page in one shot by adding custom read_page and
write_page methods. This helps in optimizing code for NAND flashes with
page size less than 4 KB.
2. If ELM module not available fall back to software BCH error
correction support.

New structure member is added to omap_nand_info
1. "is_elm_used" to know the status of whether the ELM module is used for
   error correction or not.
2. "elm_dev" device pointer to elm device on detection of ELM module.

Also being here update the device tree documentation of gpmc-nand for
adding optional property elm_id.

Note:
ECC layout uses 1 extra bytes for 512 byte of data to handle erased
pages. Extra byte programmed to zero for programmed pages. Also BCH8
requires 14 byte ecc to maintain compatibility with RBL ECC layout.
This results a common ecc layout across RBL, U-boot & Linux with BCH8.

Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2013-02-04 09:26:29 +02:00
Philip Avinash c3e4b995e4 mtd: nand: omap2: Update nerrors using ecc.strength
Remove check of ecc bytes with 13, number of errors can directly update
from nand ecc strength. This will increase re-usability of the code.
Also add macro definitions BCH8_ERROR_MAX & BCH4_ERROR_MAX for better
readability and cleaner code.

Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2013-02-04 09:26:29 +02:00