Based on DMA documentation and testing using high memory buffer when doing
dma transfers can lead to various issues including kernel panics.
To workaround this simply use cpu copy.
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
The prefetch engine sends a dma request once a FIFO threshold has
been met. No other requests are received until the previous request
is handled.
Starting a dma transfer (dma_async_issue_pending) results in any
previous event for the dma channel to be cleared. Therefore, starting
the prefetch engine before initiating the dma transfer may result in
the prefetch triggering a dma request but instead of it being handled
it can end up being cleared. This will result in a hang since the code
will continue to wait for the dma request to complete.
By initiating the dma request before enabling the prefetch engine this
race condition is avoided and no dma request are missed/cleared.
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Move constants to the right of binary operators.
Generated by: scripts/coccinelle/misc/compare_const_fl.cocci
CC: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
This is part of process deprecating NAND_ECC_SOFT_BCH (and switching to
enum nand_ecc_algo).
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Implementing the mtd_ooblayout_ops interface is the new way of exposing
ECC/OOB layout to MTD users.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
The core now takes care of parsing generic DT properties in
nand_scan_ident() when nand_set_flash_node() has been called.
Rely on this initialization instead of calling of_get_nand_xxx()
manually.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Roger Quadros <rogerq@ti.com>
Tested-by: Franklin S Cooper Jr. <fcooper@ti.com>
The GPMC WAIT pin status are now available over gpiolib.
Update the omap_dev_ready() function to use gpio instead of
directly accessing GPMC register space.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Move NAND specific device tree parsing to NAND driver.
The NAND controller node must have a compatible id, register space
resource and interrupt resource.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Copy all the platform data parameters to the driver's local data
structure 'omap_nand_info' and use it in the entire driver. This will
make it easer for device tree migration.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Instead of accessing the gpmc_status register directly start
using the gpmc_nand_ops->nand_writebuffer_empty() helper
to check write buffer empty status.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Deprecate nand register passing via platform data and use
gpmc_omap_get_nand_ops() instead.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
nand_bch_init() requires several arguments which could directly be deduced
from the mtd device. Get rid of those useless parameters.
nand_bch_init() is also requiring the caller to provide a proper eccbytes
value, while this value could be deduced from the ecc.size and
ecc.strength value. Fallback to eccbytes calculation when it is set to 0.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
The error code returned by the ecc.correct() are not consistent over the
all implementations.
Document the expected behavior in include/linux/mtd/nand.h and fix
offending implementations.
[Brian: this looks like a bugfix for the ECC reporting in the bf5xx_nand
driver, but we haven't seen any testing results for it]
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Franklin S Cooper Jr. <fcooper@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
mtd_to_nand() now uses the container_of() approach to transform an
mtd_info pointer into a nand_chip one. Drop useless mtd->priv
assignments from NAND controller drivers.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
struct nand_chip now embeds an mtd device. Make use of this mtd instance.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Define and use mtd_to_omap() instead of container_of();
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
mtd_to_nand() was recently introduced to avoid direct accesses to the
mtd->priv field. Update all NAND drivers to use it.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
All of these drivers set up a parser data struct just to communicate DT
partition data. This field has been deprecated and is instead supported
by telling nand_scan_ident() about the 'flash_node'.
This patch:
* sets chip->flash_node for those drivers that didn't already (but used
OF partitioning)
* drops the parser data
* switches to the simpler mtd_device_register() where possible, now
that we've eliminated one of the auxiliary parameters
Now that we've assigned chip->flash_node for these drivers, we can
probably rely on nand_dt_init() to do more of the DT parsing for us, but
for now, I don't want to fiddle with each of these drivers. The parsing
is done in duplicate for now on some drivers. I don't think this should
break things. (Famous last words.)
(Rolled in some changes by Boris Brezillon)
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
The ->read_xxx() methods are all passed the page number the NAND controller
is supposed to read, but ->write_xxx() do not have such a parameter.
This is a problem if we want to properly implement data
scrambling/randomization in order to mitigate MLC sensibility to repeated
pattern: to prevent bitflips in adjacent pages in the same block we need
to avoid repeating the same pattern at the same offset in those pages,
hence the randomizer/scrambler engine need to be passed the page value
in order to adapt its seed accordingly.
Moreover, adding the page parameter to the ->write_xxx() methods add some
consistency to the current API.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Josh Wu <josh.wu@atmel.com>
CC: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Huang Shijie <shijie.huang@arm.com>
CC: Stefan Agner <stefan@agner.ch>
CC: devel@driverdev.osuosl.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Make sure the device structure is properly shown in sysfs by properly
filling in dev.parent.
While at it, make use of the default owner and name values set by
mtdcore.
Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
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>
* 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
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
'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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
