On brcmnand controller v6.x and v7.x, the #WP pin is controlled through
the NAND_WP bit in CS_SELECT register.

The driver currently assumes that toggling the #WP pin is
instantaneously enabling/disabling write-protection, but it actually
takes some time to propagate the new state to the internal NAND chip
logic. This behavior is sometime causing data corruptions when an
erase/program operation is executed before write-protection has really
been disabled.

Fixes: 27c5b17c ("mtd: nand: add NAND driver "library" for Broadcom STB NAND controller")
Signed-off-by: NKamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Add a comment clarifying that NAND subpage write on keystone works,
but is not being enabled in the interest of backward compatibility.
Signed-off-by: NSekhar Nori <nsekhar@ti.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

commit c9711ec5 ("mtd: nand: omap: Clean up device tree support")
caused the parent device name to be changed from "omap2-nand.0"
to "<base address>.nand"  (e.g. 30000000.nand on omap3 platforms).
This caused mtd->name to be changed as well. This breaks partition
creation via mtdparts passed by u-boot as it uses "omap2-nand.0"
for the mtd-id.

Fix this by explicitly setting the mtd->name to "omap2-nand.<CS number>"
if it isn't already set by nand_set_flash_node(). CS number is the
NAND controller instance ID.

Fixes: c9711ec5 ("mtd: nand: omap: Clean up device tree support")
Cc: <stable@vger.kernel.org> # 4.7+
Reported-by: NLeto Enrico <enrico.leto@siemens.com>
Reported-by: NAdam Ford <aford173@gmail.com>
Suggested-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: NAdam Ford <aford173@gmail.com>
Signed-off-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

of_device_id tables should be NULL terminated.

Fixes: 07b23e3db9ed ("mtd: nand: Cleanup/rework the atmel_nand driver")
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

We accidentally return 1 on error instead of proper error codes.

Fixes: 07b23e3db9ed ("mtd: nand: Cleanup/rework the atmel_nand driver")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

In some cases, nand_do_{read,write}_ops is passed with unaligned
ops->datbuf.  Drivers using DMA will be unhappy about unaligned
buffer.

The new struct member, buf_align, represents the minimum alignment
the driver require for the buffer.  If the buffer passed from the
upper MTD layer does not have enough alignment, nand_do_*_ops will
use bufpoi.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Some NAND controllers are using DMA engine requiring a specific
buffer alignment.  The core provides no guarantee on the nand_buffers
pointers, which forces some drivers to allocate their own buffers
and pass the NAND_OWN_BUFFERS flag.

Rework the nand_buffers allocation logic to allocate each buffer
independently.  This should make most NAND controllers/DMA engine
happy, and allow us to get rid of these custom buf allocation in
NAND controller drivers.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Commit 271707b1 ("mtd: nand: denali: max_banks calculation
changed in revision 5.1") added a revision check to support the
new max_banks encoding.  Its git-log states "The encoding of
max_banks changed in Denali revision 5.1".

There are exceptional cases, for example, the revision register on
some UniPhier SoCs says the IP is 5.0 but the max_banks is encoded
in the new format.

This IP updates the resister specification from time to time (often
breaking the backward compatibility), but the revision number is not
incremented correctly.

The max_banks is not only the case that needs revision checking.
Let's allow to override an incorrect revision number.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

"pdev" is much more often used to point a platform_device, so this
will help the driver code look consistent across the kernel.

While we are here, fix "line over 80 characters" coding style
violations.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The driver sets appropriate DMA mask.  Delete the "dma-mask" DT
property.  See [1] for negative comments for this binding.

[1] https://lkml.org/lkml/2016/2/8/57Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The current driver only supports the DMA engine up to 32 bit
physical address, but there also exists 64 bit capable DMA engine
for this IP.

The data DMA setup sequence is completely different, so I added the
64 bit DMA code as a new function denali_setup_dma64().  The 32 bit
one has been renamed to denali_setup_dma32().
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

There are various customizable parameters, so several variants for
this IP.  A generic compatible like "denali,denali-nand-dt" is
useless.  Moreover, there are multiple things wrong with this string.
(Refer to Rob's comment [1])

The "denali,denali-nand-dt" was added by Altera for the SOCFPGA port.
Replace it with a more specific string "altr,socfpga-denali-nand".
There are no users (in upstream) of the old compatible string.

The Denali IP on SOCFPGA incorporates the hardware ECC fixup engine.
So, this capability should be associated with the compatible.

[1] https://lkml.org/lkml/2016/12/1/450Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Some old versions of the Denali IP (perhaps used only for Intel?)
detects ECC errors and provides correct data via a register, but
does not touch the transferred data.  So, the software must fixup
the data in the buffer according to the provided ECC correction
information.

Newer versions perform ECC correction before transferring the data.
No more software intervention is needed.  The ECC_ERROR_ADDRESS and
ECC_CORRECTION_INFO registers were deprecated.  Instead, the number
of corrected bit-flips are reported via the ECC_COR_INFO register.
When an uncorrectable ECC error happens, a status flag is set to the
INTR_STATUS and ECC_COR_INFO registers.

As is often the case with this IP, the register view of INTR_STATUS
had broken compatibility.

For older versions (SW ECC fixup):
  bit 0:  ECC_TRANSACTION_DONE
  bit 1:  ECC_ERR

For newer versions (HW ECC fixup):
  bit 0:  ECC_UNCOR_ERR
  bit 1:  Reserved

Due to this difference, the irq_mask must be fixed too.

The existing handle_ecc() has been renamed to denali_sw_ecc_fixup()
for clarification.

What is unfortunate with this feature is we can not know the total
number of corrected/uncorrected errors in a page.  The register
ECC_COR_INFO reports the maximum of per-sector bitflips.  This is
useful for ->read_page return value, but ecc_stats.{corrected,failed}
increments may not be precise.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This part is wrong in multiple ways:

[1] is_erased() is called against "buf" twice, so the OOB area is
not checked at all.  The second call should check chip->oob_poi.

[2] This code block is nested by double "if (check_erase_page)".
The inner one is redundant.

[3] The ECC_ERROR_ADDRESS register reports which sector(s) had
uncorrectable ECC errors.  It is pointless to check the whole page
if only one sector contains errors.

[4] Unfortunately, the Denali ECC correction engine has already
manipulated the data buffer before it decides the bitflips are
uncorrectable.  That is, not all of the data are 0xFF after an
erased page is processed by the ECC engine.  The current is_erased()
helper could report false-positive ECC errors.  Actually, a certain
mount of bitflips are allowed in an erased page.  The core framework
provides nand_check_erased_ecc_chunk() that takes the threshold into
account.  Let's use this.

This commit reworks the code to solve those problems.

Please note the erased page checking is implemented as a separate
helper function instead of embedding it in the loop in handle_ecc().
The reason is that OOB data are needed for the erased page checking,
but the controller can not start a new transaction until all ECC
error information is read out from the registers.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This function is wrong in multiple ways:

[1] Counting corrected bytes instead of corrected bits.

The following code is counting the number of corrected _bytes_.

    /* correct the ECC error */
    buf[offset] ^= err_cor_value;
    mtd->ecc_stats.corrected++;
    bitflips++;

What the core framework expects is the number of corrected _bits_.
They can be different if multiple bitflips occur within one byte.

[2] total number of errors instead of max of per-sector errors

The core framework expects that corrected errors are counted per
sector, then the max value should be taken.  The current code simply
iterates over the whole page, i.e. counts the total number of
correction in the page.  This means "too many bitflips" is triggered
earlier than it should be, i.e. the NAND device is worn out sooner.

Besides those bugs, this function is unreadable due to the deep
nesting.  Notice the whole code in this function is wrapped in
if (irq_status & INTR__ECC_ERR), so this conditional can be moved
out of the function.  Also, use shorter names for local variables.

Re-work the function to fix all the issues.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The pipeline read-ahead function of the Denali IP enables continuous
reading from the device; while data is being read out by a CPU, the
controller maintains additional commands for streaming data from the
device.  This will reduce the latency of the second page or later.

This feature is obviously no help for per-page accessors of Linux
NAND driver interface.

In the current implementation, the pipeline command is issued to
load a single page, then data are read out immediately.  The use of
the pipeline operation is not adding any advantage, but just adding
complexity to the code.  Remove.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Commit 28309572 ("mtd: name the mtd device with an optional
label property") allow us to identify a chip in a user-friendly way.

If nand_set_flash_node() picks up the "label" from DT, let's respect
it.  Otherwise, let it fallback to the current name "denali-nand".
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The comment for ecc.read_page() requires that it should return
"0 if bitflips uncorrectable".

Actually, drivers could return positive values when uncorrectable
bitflips occur.  For example, nand_read_page_swecc() is the case.
If ecc.correct() returns -EBADMSG for the first ECC sector, and
a positive value for the second one, nand_read_page_swecc() returns
a positive max_bitflips and increments ecc_stats.failed for the same
page.

The requirement can be relaxed by tweaking nand_do_read_ops().
Move the max_bitflips calculation below the retry.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The last/only user of the chip->write_page() hook (the Atmel NAND
controller driver) has been reworked and is no longer specifying a custom
->write_page() implementation.
Drop this hook before someone else start abusing it.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The old NAND bindings were not exactly describing the hardware topology
and were preventing definitions of several NAND chips under the same
NAND controller.

New bindings address these limitations and should be preferred over the
old ones for new SoCs/boards.
Old bindings are still supported for backward compatibility but are
marked deprecated in the doc.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: NNicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: NRob Herring <robh@kernel.org>

This is a complete rewrite of the driver whose main purpose is to
support the new DT representation where the NAND controller node is now
really visible in the DT and appears under the EBI bus. With this new
representation, we can add other devices under the EBI bus without
risking pinmuxing conflicts (the NAND controller is under the EBI
bus logic and as such, share some of its pins with other devices
connected on this bus).

Even though the goal of this rework was not necessarily to add new
features, the new driver has been designed with this in mind. With a
clearer separation between the different blocks and different IP
revisions, adding new functionalities should be easier (we already
have plans to support SMC timing configuration so that we no longer
have to rely on the configuration done by the bootloader/bootstrap).

Also note that we no longer have a custom ->cmdfunc() implementation,
which means we can now benefit from new features added in the core
implementation for free (support for new NAND operations for example).

The last thing that we gain with this rework is support for multi-chips
and multi-dies chips, thanks to the clean NAND controller <-> NAND
devices representation.

During this transition we also dropped support for AVR32 SoCs which
should soon disappear from mainline (removal of the AVR32 arch is
planned for 4.12).

This new driver has been tested on several platforms (at91sam9261,
at91sam9g45, at91sam9x5, sama5d3 and sama5d4) to make sure it did not
introduce regressions, and it's worth mentioning that old bindings are
still supported (which partly explain the positive diffstat).
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@microchip.com>

The clock gate used by orion_nand is not available on all platforms.
When getting this optional clock gate, the code masked all errors.
Let's be more precise here and actually only allow ENOENT.

EPROBE_DEFER is handled like any other error code since probe deferral
is not supported by drivers using module_platform_driver_probe().
Signed-off-by: NSimon Baatz <gmbnomis@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The clk handling in orion_nand.c had two problems:

- In the probe function, clk_put() was called for an enabled clock,
  which violates the API (see documentation for clk_put() in
  include/linux/clk.h)

- In the error path of the probe function, clk_put() could be called
  twice for the same clock.

In order to clean this up, use the managed function devm_clk_get() and
store the pointer to the clk in the driver data.

Fixes: baffab28 ('ARM: Orion: fix driver probe error handling with respect to clk')
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: NSimon Baatz <gmbnomis@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Because SUPPORT_15BITECC is defined, the following is dead code:

  #elif SUPPORT_8BITECC
          iowrite32(8, denali->flash_reg + ECC_CORRECTION);
  #endif

Such ifdefs are useless and unacceptable coding style.

These writes are not needed in the first place since ECC_CORRECTION
is set up by the nand_init() function.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The write accesses to LOGICAL_PAGE_{DATA,SPARE}_SIZE have no effect
because the Denali User's Guide says these registers are read-only.

The hardware automatically multiplies the main/spare size by the
number of devices and update LOGICAL_PAGE_{DATA,SPARE}_SIZE.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Currently, the driver expects DEVICE_CONNECTED is automatically set
by the hardware, but this feature is disabled in some cases.
In such cases, it is the software's responsibility to set up the
DEVICES_CONNECTED register.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The available configuration of the IP bus width is x8 or x16, so the
possible value for denali->devnum is 1 or 2.

If the value is 1, there is nothing to do.  Fixup parameters only
when denali->devnum is 2.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Collect multi NAND fixups into a helper function instead of
scattering them in denali_init().

I am rewording the comment block to clearly explain what is called
"multi device".
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This will allow nand_dt_init() to parse DT properties in the NAND
controller device node.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The denali_init() needs to setup a bunch of parameters of nand_chip.
Replace denali->nand.(member) with chip->(member) for shorter code.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Set Features (0xEF) command toggles the R/B# pin after 4 sub feature
parameters are written.

Currently, nand_command(_lp) calls chip->dev_ready immediately after
the address cycle because NAND_CMD_SET_FEATURES falls into default:
label.  No wait is needed at this point.

If you see nand_onfi_set_features(), R/B# is already cared by the
chip->waitfunc call.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Read ID (0x90) command does not toggle the R/B# pin.  Without this
patch, NAND_CMD_READID falls into the default: label, then R/B# is
checked by chip->dev_ready().
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The page number is generally stored in an integer type variable.
The uint16_t does not have enough width.  I see no reason to use
uint32_t for other members, either.  Just use int.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The Denali NAND controller IP has various customizable features.
SoC vendors can choose desired functions when a delivery RTL is
created.  It means there are several variants for this IP.  For
example, the Intel version is equipped with 32bit DMA, whereas the
IP for UniPhier SoC family with 64bit DMA.

This driver was originally written for some Intel platforms with
Intel specific things hard-coded.  What is worse, the revision
register of this IP does not work to distinguish such features.
We need to do something to make the driver available for other SoCs.

Let's introduce a caps member to the denali_nand_info structure to
switch on/off various features.  Also, add struct denali_dt_data to
store the capability associated with compatible string.

Boris suggested this approach in discussion [1] instead of a new DT
property for every feature.

[1] https://lkml.org/lkml/2016/3/29/142Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The interrupts are enabled by INTR_EN register, then asserted
interrupts can be observed via INTR_STATUS register.

The bit fields are identical between INTR_EN and INTR_STATUS, so we
can merge the bit field macros.  Likewise for DATA_INTR.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The same comment "Mapped io reg base address" for flash_reg and
flash_mem probably due to the mistake of copy-paste work.
Of course, the latter is not the register base address.

Reword the comments using the terminology in the Denali User's Guide.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

These members are not used at all.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This macro is defined twice in denali.c (around line 98 and
line 651), so remove the second one.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

All of these macros are not used at all.
CONFIG_MTD_NAND_DENALI_SCRATCH_REG_ADDR is not used for anything but
defining SCRATCH_REG_ADDR.  The config option should go away as well.

I am removing some register macros.  They are not used, and do not
exist in recent IP versions.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The nand_default_block_markbad() and scan_block_fast() use high
level APIs to get access to the BBM.

On the other hand, nand_block_bad (the default implementation of
->block_bad) calls the lower level ->cmdfunc hook.  This prevents
drivers from using ->ecc.read_oob() even if optimized read operation
is implemented.  Besides, some NAND controllers may protect the BBM
with ECC.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>