This commit improves the ->setup_data_interface() hook.

The denali_setup_data_interface() needs the frequency of clk_x
and the ratio of clk_x / clk.

The latter is currently hardcoded in the driver, like this:

  #define DENALI_CLK_X_MULT       6

The IP datasheet requires that clk_x / clk be 4, 5, or 6.  I just
chose 6 because it is the most defensive value, but it is not optimal.
By getting the clock rate of both "clk" and "clk_x", the driver can
compute the timing values more precisely.

To not break the existing platforms, the fallback value, 50 MHz is
provided.  It is true for all upstreamed platforms.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Currently, denali_dt.c requires a single anonymous clock, but
the Denali User's Guide requires three clocks for this IP:

 - clk: controller core clock

 - clk_x: bus interface clock

 - ecc_clk: clock at which ECC circuitry is run

This commit supports these named clocks to represent the real hardware.

For the backward compatibility, the driver still accepts a single clock
just as before.  The clk_x_rate is taken from the clock driver again if
the named clock "clk_x" is available.  This will happen only for future
DT, hence the existing DT files are not affected.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Commit 30f9f2fb ("mtd: denali: add a DT driver") supported the
clock enablement, but did not document it in the DT binding.

In addition to the existing clock, this commit adds more clocks based
on the IP specification.

According to the Denali User's Guide, this IP needs three clocks:

 - clk: controller core clock

 - clk_x: bus interface clock

 - ecc_clk: clock at which ECC circuitry is run

The driver should accept the current single clock for the backward
compatibility, but the DT binding should represent the real hardware,
and future platforms must follow this.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

The probe function references &pdev->dev many times, and I will add
more soon.  Add 'dev' as a shorthand.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Using the sysfs unbind, bind nodes, mxcnd_probe and mxcnd_probe_dt can
potentially be called at any time. After the __init functions are cleaned,
mxcnd_probe_dt is no longer available. Calling it anyway causes a crash.

mxcnd_probe used to be marked as __init, this was removed years ago.
Remove the __init qualifier from from mxcnd_probe_dt as well.

Fixes: 06f25510 ("mtd: remove use of __devinit")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

MX35LF2GE4AB is almost identical to MX35LF1GE4AB except it has 2 times
more eraseblocks per LUN and exposes 2 planes instead of 1.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

Add minimal support for the MX35LF1GE4AB SPI NAND chip.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Add support for the W25M02GV chip.
Signed-off-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Add a basic driver for Micron SPI NANDs. Only one device is supported
right now, but the driver will be extended to support more devices
afterwards.
Signed-off-by: Peter Pan <peterpandong@micron.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Add bindings for SPI NAND chips.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Add a SPI NAND framework based on the generic NAND framework and the
spi-mem infrastructure.

In its current state, this framework supports the following features:

- single/dual/quad IO modes
- on-die ECC
Signed-off-by: Peter Pan <peterpandong@micron.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Function nand_ecc_choose_conf() will be help for all the cases, so
other helper functions can be made static.

nand_check_ecc_caps(): Invoke nand_ecc_choose_conf() with
                       both chip->ecc.size and chip->ecc.strength
                       value set.

nand_maximize_ecc(): Invoke nand_ecc_choose_conf() with
                     NAND_ECC_MAXIMIZE flag.

nand_match_ecc_req(): Invoke nand_ecc_choose_conf() with either
                      chip->ecc.size or chip->ecc.strength value
                      set and without NAND_ECC_MAXIMIZE flag.

CC: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Make separate function to perform raw read for one codeword and
call this function multiple times for each codeword in case of
raw page read. This separate function will help in subsequent
patches related with erased codeword bitflip detection.

It will decrease throughput for raw page read. Raw page read
is used for debug purpose so it won't affect normal flash
operations.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Currently there is no error checking for raw read. For raw
reads, there won’t be any ECC failure but the operational
failures are possible, so schedule the NAND_FLASH_STATUS read
after each codeword.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Fix value returned by ->read_page_raw() to be the
actual operation status, instead of always 0.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

QCOM NAND controller layout protects available OOB data bytes with
ECC also so when ecc->write_oob() is being called then it
can't update just OOB bytes. Currently, it first reads the last
codeword which includes old OOB bytes. Then it updates the old OOB
bytes with new ones and then again writes the codeword back.
The reading codeword is unnecessary since user is responsible to
have these bytes cleared to 0xFF.

This patch removes the read part and updates the OOB bytes with
data area padded with OxFF.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

read_page and read_oob both calls the read_page_ecc function.
The QCOM NAND controller protect the OOB available bytes with
ECC so read errors should be checked for read_oob also.
This patch moves the error checking code inside read_page_ecc
so caller does not have to check explicitly for read errors.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

parse_read_errors can be called with only oob_buf in which case
data_buf will be NULL.  If data_buf is NULL, then don’t
treat this page as completely erased in case of ECC uncorrectable
error for RS ECC. For BCH ECC, the controller itself tells
regarding erased page in status register.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Following is the flow in the HW if controller tries to read erased
page:

1. First ECC uncorrectable error will be generated from ECC engine
   since ECC engine first calculates the ECC with all 0xff and match
   the calculated ECC with ECC code in OOB (which is again all 0xff).
2. After getting ECC error, erased CW detection logic will be
   applied which is different for BCH and RS ECC
    a. For BCH, HW checks if all the bytes in page are 0xff and then
       it updates the status in separate register
       NAND_ERASED_CW_DETECT_STATUS.
    b. For RS ECC, the HW reports the same error when reading an
       erased CW, but it notifies that it is an erased CW by
       placing special characters at certain offsets in the
       buffer.

So the erased CW detect status should be checked only if ECC engine
generated the uncorrectable error.

Currently for all other operational errors also (like TIMEOUT, MPU
errors, etc.), the erased CW detect logic is being applied so fix this
and return EIO for other operational errors.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

The BAM has 3 channels - tx, rx and command. command channel
is used for register read/writes, tx channel for data writes
and rx channel for data reads. Currently, the driver assumes the
transfer completion once it gets all the command descriptors
completed. Sometimes, there is race condition between data channel
(tx/rx) and command channel completion. In these cases,
the data present in buffer is not valid during small window
between command descriptor completion and data descriptor
completion.

This patch generates NAND transfer completion when both
(Data and Command) DMA channels have completed all its DMA
descriptors. It assigns completion callback in last
DMA descriptors of that channel and wait for completion.

Fixes: 8d6b6d7e ("mtd: nand: qcom: support for command descriptor formation")
Cc: stable@vger.kernel.org
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Currently the driver uses the ECC strength specified in DT.
The QPIC/EBI2 NAND supports 4 or 8-bit ECC correction. The same
kind of board can have different NAND parts so use the ECC
strength from device parameters if it is not specified in DT.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

QCOM NAND controller supports only one step size (512) so
nand-ecc-step-size DT property is redundant. This property
can be removed and ecc step size can be assigned with 512 value.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

1. If nand-ecc-strength specified in DT, then controller will use
   this ECC strength otherwise ECC strength will be calculated
   according to chip requirement and available OOB size.

2. QCOM NAND controller supports only one step size (512 bytes) but
   nand-ecc-step-size is required property in DT. This DT property
   can be removed and ecc step size can be assigned in driver with
   512 bytes value.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Use the NAND core helper function nand_ecc_choose_conf to tune
the ECC parameters instead of the function locally defined.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

commit 2c8f8afa ("mtd: nand: add generic helpers to check,
match, maximize ECC settings") provides generic helpers which
drivers can use for setting up ECC parameters.

Since same board can have different ECC strength nand chips so
following is the logic for setting up ECC strength and ECC step
size, which can be used by most of the drivers.

1. If both ECC step size and ECC strength are already set
   (usually by DT) then just check whether this setting
   is supported by NAND controller.
2. If NAND_ECC_MAXIMIZE is set, then select maximum ECC strength
   supported by NAND controller.
3. Otherwise, try to match the ECC step size and ECC strength closest
   to the chip's requirement. If available OOB size can't fit the chip
   requirement then select maximum ECC strength which can be fit with
   available OOB size.

This patch introduces nand_ecc_choose_conf function which calls the
required helper functions for the above logic. The drivers can use
this single function instead of calling the 3 helper functions
individually.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Some Micron NAND chips (MT29F1G08ABAFAWP-ITE:F) report 00 00 for the
revision number field of the ONFI parameter page. Rather than rejecting
these outright assume ONFI version 1.0 if the revision number is 00 00.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Add defines for the ONFI version bits and use them in
nand_flash_detect_onfi().
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

This is called after the ONFI parameter page checksum is verified
and allows us to override the contents of the parameter page.
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

>From the controllers point of view this is the same as no or
software only ECC.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Add support for the NAND flash controller found on NVIDIA
Tegra 2 SoCs. This implementation does not make use of the
command queue feature. Regular operations using ->exec_op()
use PIO mode for data transfers. Raw, ECC and OOB read/writes
make use of the DMA mode for data transfer.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

This adds the devicetree binding for the Tegra 2 NAND flash
controller.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Allow to define a NAND chip as a boot device. This can be helpful
for the selection of the ECC algorithm and strength in case the boot
ROM supports only a subset of controller provided options.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Add Reed-Solomon (RS) to the enumeration of ECC algorithms.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

The datasheet of the H27UCG8T2BTR states that this chip has a page size
of "16,384 + 1,280(Spare) bytes". The description of the "4th Byte of
Device Identifier Description" indicates that bits 6, 3 and 2 are
encoding the "Redundant Area Size / 8KB", where 640 bytes is a value of
0x6 (110 in binary notation).

hynix_nand_extract_oobsize decodes an OOB size of 640 bytes for this
chip. Kernel boot log extract before this patch:
nand: Could not find valid ONFI parameter page; aborting
nand: device found, Manufacturer ID: 0xad, Chip ID: 0xde
nand: Hynix NAND 8GiB 3,3V 8-bit
nand: 8192 MiB, MLC, erase size: 4096 KiB, page size: 16384,
      OOB size: 640

However, based on the description in the datasheet we need to multiply
the OOB size with 2, because it's "640 spare bytes per 8192 bytes page
size" and this NAND chip has a page size of 16384 (= 2 * 8192). After
this patch the kernel boot log reports:
nand: Could not find valid ONFI parameter page; aborting
nand: device found, Manufacturer ID: 0xad, Chip ID: 0xde
nand: Hynix NAND 8GiB 3,3V 8-bit
nand: 8192 MiB, MLC, erase size: 4096 KiB, page size: 16384,
      OOB size: 1280
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Even if we can't update ecc_stats.corrected with an accurate value we
should at least increase the number of bitflips so that MTD users can
know that there was some bitflips.

Just add chip->ecc.strength to mtd->ecc_stats.corrected which should
account for the worst case situation.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

On a sama5d31 with a Full-HD dual LVDS panel (132MHz pixel clock) NAND
flash accesses have a tendency to cause display disturbances. Add a
module param to disable DMA from the NAND controller, since that fixes
the display problem for me.
Signed-off-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Pull btrfs fixes from David Sterba:
 "We have a few regression fixes for qgroup rescan status tracking and
  the vm_fault_t conversion that mixed up the error values"

* tag 'for-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix mount failure when qgroup rescan is in progress
  Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion
  btrfs: quota: Set rescan progress to (u64)-1 if we hit last leaf

Pull vfs fix from Al Viro:
 "Followup to procfs-seq_file series this window"

This fixes a memory leak by making sure that proc seq files release any
private data on close.  The 'proc_seq_open' has to be properly paired
with 'proc_seq_release' that releases the extra private data.

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  proc: add proc_seq_release

Pull staging/IIO fixes from Greg KH:
 "Here are a few small staging and IIO driver fixes for 4.18-rc3.

  Nothing major or big, all just fixes for reported problems since
  4.18-rc1. All of these have been in linux-next this week with no
  reported problems"

* tag 'staging-4.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: android: ion: Return an ERR_PTR in ion_map_kernel
  staging: comedi: quatech_daqp_cs: fix no-op loop daqp_ao_insn_write()
  iio: imu: inv_mpu6050: Fix probe() failure on older ACPI based machines
  iio: buffer: fix the function signature to match implementation
  iio: mma8452: Fix ignoring MMA8452_INT_DRDY
  iio: tsl2x7x/tsl2772: avoid potential division by zero
  iio: pressure: bmp280: fix relative humidity unit