As the devicetree binding doesn't require num_cs to exist or be strictly
positive, and neither does the platform data case, a bug appear when
num_cs is set to 0 and panics the kernel.

The issue is that in alloc_nand_resource(), chip is dereferenced without
having a value assigned when num_cs == 0.

Fix this by returning ENODEV is num_cs == 0.

The panic seen is :
Unable to handle kernel NULL pointer dereference at virtual address 000002b8
pgd = c0004000
[000002b8] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT ARM
Modules linked in:
Hardware name: Marvell PXA3xx (Device Tree Support)
task: c3822aa0 ti: c3826000 task.ti: c3826000
PC is at alloc_nand_resource+0x180/0x4a8
LR is at alloc_nand_resource+0xa0/0x4a8
pc : [<c0275b90>]    lr : [<c0275ab0>]    psr: 68000013
sp : c3827d90  ip : 00000000  fp : 00000000
r10: c3862200  r9 : 0000005e  r8 : 00000000
r7 : c3865610  r6 : c3862210  r5 : c3924210  r4 : c3862200
r3 : 00000000  r2 : 00000000  r1 : 00000000  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 0000397f  Table: 80004018  DAC: 00000035
Process swapper (pid: 1, stack limit = 0xc3826198)
Stack: (0xc3827d90 to 0xc3828000)
...zip...
[<c0275b90>] (alloc_nand_resource) from [<c0275ff8>] (pxa3xx_nand_probe+0x140/0x978)
[<c0275ff8>] (pxa3xx_nand_probe) from [<c0258c40>] (platform_drv_probe+0x48/0xa4)
[<c0258c40>] (platform_drv_probe) from [<c0257650>] (driver_probe_device+0x80/0x21c)
[<c0257650>] (driver_probe_device) from [<c0257878>] (__driver_attach+0x8c/0x90)
[<c0257878>] (__driver_attach) from [<c0255ec4>] (bus_for_each_dev+0x58/0x88)
[<c0255ec4>] (bus_for_each_dev) from [<c0256ec8>] (bus_add_driver+0xd8/0x1d4)
[<c0256ec8>] (bus_add_driver) from [<c0257f14>] (driver_register+0x78/0xf4)
[<c0257f14>] (driver_register) from [<c00088a8>] (do_one_initcall+0x80/0x1e4)
[<c00088a8>] (do_one_initcall) from [<c048ed08>] (kernel_init_freeable+0xec/0x1b4)
[<c048ed08>] (kernel_init_freeable) from [<c0377d8c>] (kernel_init+0x8/0xe4)
[<c0377d8c>] (kernel_init) from [<c00095f8>] (ret_from_fork+0x14/0x3c)
Code: e503b234 e5953008 e1530001 caffffd1 (e59002b8)
---[ end trace a5770060c8441895 ]---
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Acked-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The NDDB register holds the data that are needed by the read and write
commands.

However, during a read PIO access, the datasheet specifies that after each 32
bytes read in that register, when BCH is enabled, we have to make sure that the
RDDREQ bit is set in the NDSR register.

This fixes an issue that was seen on the Armada 385, and presumably other mvebu
SoCs, when a read on a newly erased page would end up in the driver reporting a
timeout from the NAND.

Cc: <stable@vger.kernel.org> # v3.14
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The intent was to mask away some bits here, not to test true or false.

Fix: 54f531f6 ('mtd: hisilicon: add a new NAND controller driver for hisilicon hip04 Soc')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

This patch adds the support for hisilicon 504 NAND controller which is now used
by Hisilicon Soc Hip04.
Signed-off-by: NZhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The PPC_OF is a ppc specific option which is used to mean that the
firmware device tree access functions are available. Since all the
ppc platforms have a device tree, it is aways set to 'y' for ppc.
So it makes no sense to keep a such option in the current kernel.
Replace it with PPC.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

This driver uses NAND_ECC_HW_SYNDROME mode.  The nand_scan_tail()
function would not complain about missing ecc->calculate,
ecc->correct, ecc->hwctl handlers.
Signed-off-by: NMasahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NBrian 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: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NNicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: NPekon Gupta <pekon@pek-sem.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Use the GPIO descriptor API instead of the deprecated legacy GPIO API to
manage the busy GPIO.

The patch updates both the jz4740 nand driver and the only user of the driver
the qi-lb60 board driver.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Previously, we requested that drivers pass ecc.size and ecc.bytes when
using NAND_ECC_SOFT_BCH. However, a driver is likely to only know the ECC
strength required for its NAND, so each driver would need to perform a
strength-to-bytes calculation.

Avoid duplicating this calculation in each driver by asking drivers to
pass ecc.size and ecc.strength so that the strength-to-bytes calculation
need only be implemented once.

This reverts/generalizes this commit:
    mtd: nand: Base BCH ECC bytes on required strength
Signed-off-by: NAaron Sierra <asierra@xes-inc.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The MTD API reports -EUCLEAN only if the maximum number of bitflips
found in any ECC block exceeds a certain threshold. This is done to
avoid excessive -EUCLEAN reports to MTD users, which may induce
additional scrubbing of data, even when the ECC algorithm in use is
perfectly capable of handling the bitflips.

This threshold can be controlled by user-space (via sysfs), to allow
users to determine what they are willing to tolerate in their
application. But it still helps to have sane defaults.

In recent discussion [1], it was pointed out that our default threshold
is equal to the correction strength. That means that we won't actually
report any -EUCLEAN (i.e., "bitflips were corrected") errors until there
are almost too many to handle. It was determined that 3/4 of the
correction strength is probably a better default.

[1] http://lists.infradead.org/pipermail/linux-mtd/2015-January/057259.htmlSigned-off-by: NBrian Norris <computersforpeace@gmail.com>
Acked-by: NHuang Shijie <shijie.huang@intel.com>

Since in SAMA5D4 chip, the PMECC can correct bit flips in erased page.
So we add a DT property to indicate this hardware character.

If the PMECC support correct bitflip erased page (all data are 0xff).
Then we can use the PMECC correct the page and skip the erased page
check.
Signed-off-by: NJosh Wu <josh.wu@atmel.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

atmel_nand_pmecc_read_page() will return the total bitflips in this
page. This is incorrect.

As one nand page includes multiple ecc sectors, that will cause the
returned total bitflips exceed ecc capablity.

So this patch will make pmecc_correct() return the max bitflips of all
sectors in the page. That also makes atmel_nand_pmecc_read_page() return
the max bitflips.
Signed-off-by: NJosh Wu <josh.wu@atmel.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

There is no path to switch to STATE_DATAOUT_STATUS_M state, and
OPT_SMARTMEDIA is unused.

This is leftover from commit 0be718e5
("mtd: nand: remove a bunch of unused commands").
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

In initialization routine, mtd_info->owner is overwritten by memset()
just after being initialized.  This can be fixed by moving memset() calls
to just before setting mtd_info->owner.  But the memory region is allocated
by kmalloc, so we can fix it by using kzalloc instead of kmalloc.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Jonathan McDowell <noodles@earth.li>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

commit 3157d1ed ("mtd: denali: remove unnecessary casts") introduced
an error by using a wrong bitmask.

A uint16_t cast was replaced with & 0xff, should be & 0xffff.
Signed-off-by: NGraham Moore <grmoore@opensource.altera.com>
Signed-off-by: NDinh Nguyen <dinguyen@opensource.altera.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Commit 7854d3f7 ("mtd: spelling, capitalization, uniformity") added
a correctly spelled line, but failed to remove the wrongly spelled one.
Commit 064a7694 ("mtd: Fix typo mtd/tests") then fixed the spelling
again, but left the duplication.

Fixes: 7854d3f7 ("mtd: spelling, capitalization, uniformity")
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Add nand_shutdown to wait for current nand operations to finish and prevent
further operations by changing the nand flash state to FL_SHUTDOWN.

This is addressing a problem observed during reboot tests using UBIFS
root file system: NAND erase operations that are in progress during
system reboot/shutdown are causing partial erased blocks. Although UBI should
be able to detect and recover from this error, this change will avoid
the creation of partial erased blocks on reboot in the middle of a NAND erase
operation.
Signed-off-by: NScott Branden <sbranden@broadcom.com>
Tested-by: NScott Branden <sbranden@broadcom.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Now that we have raw functions properly implemented we can remove this
FIXME.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NHuang Shijie <shijie.huang@intel.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

mx28evk board has a socket for NAND flash that comes with no NAND flash
populated, and then we get this message on every boot:

[    1.657603] gpmi-nand 8000c000.gpmi-nand: driver registration failed: -19

which is not very helpful, so get rid of this error message.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Implement raw OOB access functions to retrieve OOB bytes when accessing the
NAND in raw mode.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: NHuang Shijie <shijie8@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Several MTD users (either in user or kernel space) expect a valid raw
access support to NAND chip devices.
This is particularly true for testing tools which are often touching the
data stored in a NAND chip in raw mode to artificially generate errors.

The GPMI drivers do not implemenent raw access functions, and thus rely on
default HW_ECC scheme implementation.
The default implementation consider the data and OOB area as properly
separated in their respective NAND section, which is not true for the GPMI
controller.
In this driver/controller some OOB data are stored at the beginning of the
NAND data area (these data are called metadata in the driver), then ECC
bytes are interleaved with data chunk (which is similar to the
HW_ECC_SYNDROME scheme), and eventually the remaining bytes are used as
OOB data.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: NHuang Shijie <shijie8@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Add a new function to copy bits (not bytes) from a memory region to
another one.
This function is similar to memcpy except it acts at bit level.
It is needed to implement GPMI raw access functions and adapt to the
hardware ECC engine which does not pad ECC bits to the next byte boundary.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: NHuang Shijie <shijie8@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

There is no need to use memcpy32_toio/memcpy32_fromio to transfer data
between memory and NFC sram. As the NFC sram is a also a memory space
not an I/O space, we can just use memcpy().

We remove the __iomem prefix for NFC sram to avoid sparse warnings.
Signed-off-by: NJosh Wu <josh.wu@atmel.com>
Reviewed-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

This write_page() function is functionally equivalent to the default in
nand_base.c. Its only difference is in subpage programming support,
which cafe_nand.c does not advertise, so the difference is negligible.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

3430LDP has NAND flash with 32 bytes OOB size which is sufficient to hold
BCH8 codes but the small page check introduced in
commit b491da72 ("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: b491da72 ("mtd: nand: omap: clean-up ecc layout for BCH ecc schemes")
Reported-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Tested with ATO AFND1G08U3, 128MiB NAND.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

It may be useful info, e.g. if someone wants to use ubinize.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Freescale's QorIQ T Series processors support 8 IFC chip selects
within a memory map backward compatible with previous P Series
processors which supported only 4 chip selects.
Signed-off-by: NAaron Sierra <asierra@xes-inc.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

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

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

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

For more information can refer to section 5.4 of PMECC controller
application note:
	http://www.atmel.com/images/doc11127.pdfSigned-off-by: NJosh Wu <josh.wu@atmel.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The driver was also using own method to do 32bit copy, turns out
we have a kernel API so use that instead
Signed-off-by: NVinod Koul <vinod.koul@intel.com>
Signed-off-by: NBrian 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 97a288ba ("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: NRostislav Lisovy <lisovy@merica.cz>
Acked-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

update a comment in nand_command_lp() about specific requirements of
individual commands, the DEPLETE1 command was removed in the past and
the comment no longer applied
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

NAND devices with page sizes over 4 KiB require more than 4-bits of ECC
coverage. This patch calculates the value of ecc_bytes based on a still
assumed 512-byte step size (13-bits) and the ecc_strength.

Example:
Micron M73A devices (8 KiB page) require 8-bit ECC per 512-byte
Signed-off-by: NJordan Friendshuh <jfriendshuh@xes-inc.com>
Signed-off-by: NAaron Sierra <asierra@xes-inc.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The drivers/mtd/nand/gpio.c driver does not GPIO bitbang the complete
NAND protocol, but instead is GPIO _assisted_ -- a memory mapped interface
communicates commands and data, and only few control signals are connected
to GPIO pins.

Expand comments in the driver source and in the Kconfig description to
better reflect the very nature of the driver.  The previous text could be
mistaken for complete GPIO bitbanging.
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Since commit 6d178ef2 ("mtd: nand: Move ELM driver and rename as
omap_elm"), I don't have any mtd devices present on my am335x. This
changes the link order of the omap_elm and omap2 objects, causing them
to probe in the wrong order.

To fix this, make elm_config defer probing until the omap_elm driver is
actually loaded.
Signed-off-by: NFrans Klaver <frans.klaver@xsens.com>
Acked-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Add support for the sunxi NAND Flash Controller (NFC).
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
[Brian: tweaked to fix ecc->steps issue]
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

nandsim can simulate NAND Flash which returns the ID bytes specified
by first_id_byte, ..., fourth_id_byte module parameters.

In order to simulate NAND flash which returns more than four ID bytes,
this adds id_bytes module parameter which is specified by the array of
byte like this:

 # modprobe nandsim id_bytes=0x98,0xdc,0x90,0x26,0x76,0x15,0x01,0x08 bch=1

This doesn't add fifth_id_byte, ..., seventh_id_byte module parameters,
because they are redundant.  But the existing first_id_byte, ...,
fourth_id_byte module parameters are preserved and add "(obsolete)" to
the description.

Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

This replaces kzalloc() and ioremap() calls by devm_ functions
in the probe() routine, which automatically release the corresponding
resources when probe() fails or when the device is removed.

This simplifies simplifies the error management code, and brings
the below improvements or changes:

A. Fixing a bug reported by "make coccicheck":

If "board = devm_kzalloc()" fails, the probe() function jumps
incorrectly to label "no_res" and therefore returns without
running iounmap().

B. Requesting the memory region

Using devm_ioremap_resource() makes the probe() function request
the corresponding memory region before running ioremap(), as
it is supposed to do.

C. Standardizing the error codes:

The use of devm_ioremap_resource() changes the return value:
 * -ENOMEM instead of -EIO in case of ioremap() failure,
 * -EINVAL instead of -ENODEV in case of platform_get_resource()
   failure.
Signed-off-by: NMichael Opdenacker <michael.opdenacker@free-electrons.com>
Reviewed-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>