In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warning:

drivers/mtd/nand/raw/diskonchip.c: In function ‘doc_probe’:
./include/linux/printk.h:303:2: warning: this statement may fall through [-Wimplicit-fallthrough=]
  printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mtd/nand/raw/diskonchip.c:1479:4: note: in expansion of macro ‘pr_err’
    pr_err("DiskOnChip Millennium Plus 32MB is not supported, ignoring.\n");
    ^~~~~~
drivers/mtd/nand/raw/diskonchip.c:1480:3: note: here
   default:
   ^~~~~~~
drivers/mtd/nand/raw/nandsim.c: In function ‘ns_init_module’:
drivers/mtd/nand/raw/nandsim.c:2254:22: warning: this statement may fall through [-Wimplicit-fallthrough=]
    chip->bbt_options |= NAND_BBT_NO_OOB;
drivers/mtd/nand/raw/nandsim.c:2255:2: note: here
  case 1:
  ^~~~
drivers/mtd/nand/raw/nuc900_nand.c: In function ‘nuc900_nand_command_lp’:
./arch/x86/include/asm/io.h:91:22: warning: this statement may fall through [-Wimplicit-fallthrough=]
 #define __raw_writel __writel
drivers/mtd/nand/raw/nuc900_nand.c:52:2: note: in expansion of macro ‘__raw_writel’
  __raw_writel((val), (dev)->reg + REG_SMCMD)
  ^~~~~~~~~~~~
drivers/mtd/nand/raw/nuc900_nand.c:196:3: note: in expansion of macro ‘write_cmd_reg’
   write_cmd_reg(nand, NAND_CMD_READSTART);
   ^~~~~~~~~~~~~
drivers/mtd/nand/raw/nuc900_nand.c:197:2: note: here
  default:
  ^~~~~~~
drivers/mtd/nand/raw/omap_elm.c: In function ‘elm_context_restore’:
drivers/mtd/nand/raw/omap_elm.c:512:4: warning: this statement may fall through [-Wimplicit-fallthrough=]
    elm_write_reg(info, ELM_SYNDROME_FRAGMENT_4 + offset,
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      regs->elm_syndrome_fragment_4[i]);
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mtd/nand/raw/omap_elm.c:514:3: note: here
   case BCH8_ECC:
   ^~~~
drivers/mtd/nand/raw/omap_elm.c:517:4: warning: this statement may fall through [-Wimplicit-fallthrough=]
    elm_write_reg(info, ELM_SYNDROME_FRAGMENT_2 + offset,
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      regs->elm_syndrome_fragment_2[i]);
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mtd/nand/raw/omap_elm.c:519:3: note: here
   case BCH4_ECC:
   ^~~~
drivers/mtd/nand/raw/omap_elm.c: In function ‘elm_context_save’:
drivers/mtd/nand/raw/omap_elm.c:466:37: warning: this statement may fall through [-Wimplicit-fallthrough=]
    regs->elm_syndrome_fragment_4[i] = elm_read_reg(info,
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
      ELM_SYNDROME_FRAGMENT_4 + offset);
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mtd/nand/raw/omap_elm.c:468:3: note: here
   case BCH8_ECC:
   ^~~~
drivers/mtd/nand/raw/omap_elm.c:471:37: warning: this statement may fall through [-Wimplicit-fallthrough=]
    regs->elm_syndrome_fragment_2[i] = elm_read_reg(info,
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
      ELM_SYNDROME_FRAGMENT_2 + offset);
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mtd/nand/raw/omap_elm.c:473:3: note: here
   case BCH4_ECC:
   ^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Now that the CS line to be selected is passed to ->exec_op() and
stored in chip->cur_cs and after patching all drivers implementing
->exec_op() to stop implementing this method, we can deprecate it by
moving it to the nand_legacy structure.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

The wait timeouts and delays are directly extracted from the NAND
timings and ->chip_delay is only used in legacy path, so let's move it
to the nand_legacy struct to make it clear.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Those hooks have been overloaded by some drivers for bad reasons:
either the driver was not fitting in the NAND framework and should
have been an MTD driver (docg4), or it was not properly implementing
the OOB read/write request or had a weird layout where BBM are trashed.
In any case, we should discourage people from overloading those
methods and encourage them to fix their driver instead.

Move the ->block_{bad,markbad}() hooks to the nand_legacy struct to
make it clear.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Those hooks have been replaced by ->exec_op(). Move them to the
nand_legacy struct.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Those hooks have been replaced by ->exec_op(). Move them to the
nand_legacy struct.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

All those hooks have been replaced by ->exec_op(). Move them to the
nand_legacy struct.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->waitfunc() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->cmdfunc() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->dev_ready() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->cmd_ctrl() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all chip->block_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->select_chip() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all chip->write_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all chip->read_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one.

Now is ecc->correct()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one.

Now is ecc->calculate()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one.

Now is ecc->hwctl()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers to
take a nand_chip object instead of an mtd_info one.

Now is nand_release()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers to take
a nand_chip object instead of an mtd_info one.

We start with nand_scan().
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

None of the existing drivers are overloading the ->scan_bbt() method,
let's get rid of it and replace calls to ->scan_bbt() by
nand_create_bbt() ones.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

doc_probe() is never called in atomic context.

doc_probe() is only called by init_nanddoc(), which is only set as
a parameter of module_init().
This function is not called in atomic context.

Despite never getting called from atomic context, doc_probe()
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.
Signed-off-by: NJia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

The reed solomon library is moving the on stack decoder buffers into the rs
control structure. That would break the DoC driver because multiple
instances share the same control structure and can operate in parallel. At
least in theory....

Instantiate a rs control instance per DoC device to avoid that. The per
instance buffer is fine as the operation on a single DoC instance is
serialized by the MTD/NAND core.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Kernel Hardening <kernel-hardening@lists.openwall.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Andrew Morton <akpm@linuxfoundation.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alasdair Kergon <agk@redhat.com>
Signed-off-by: NKees Cook <keescook@chromium.org>

The decoder library uses variable length arrays on stack. To get rid of
them it would be simple to allocate fixed length arrays on stack, but those
might become rather large. The other solution is to allocate the buffers in
the rs control structure, but this cannot be done as long as the structure
can be shared by several users. Sharing is desired because the RS polynom
tables are large and initialization is time consuming.

To solve this split the codec information out of the control structure and
have a pointer to a shared codec in it. Instantiate the control structure
for each user, create a new codec if no shareable is avaiable yet.  Adjust
all affected usage sites to the new scheme.

This allows to add per instance decoder buffers to the control structure
later on.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Kernel Hardening <kernel-hardening@lists.openwall.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Andrew Morton <akpm@linuxfoundation.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alasdair Kergon <agk@redhat.com>
Signed-off-by: NKees Cook <keescook@chromium.org>

Using pr_<loglevel>() is more concise than printk(KERN_<LOGLEVEL>).
Replace printks having a log level with the appropriate pr_*() macros.
Define pr_fmt() and remove other additional macros from the replaced
printks.
Signed-off-by: NShreeya Patel <shreeya.patel23498@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

As part of the process of sharing more code between different NAND
based devices, we need to move all raw NAND related code to the raw/
subdirectory.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

Some files add a comment giving the path of the file inside the Linux
tree, which is pretty useless since the reader had to find the file to
open it.

Getting rid of these comments will also allow us to easily move these
files around when needed.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

This is part of the process of removing direct calls to ->cmdfunc()
outside of the core in order to introduce a better interface to execute
NAND operations.

Here we provide several helpers and make use of them to remove all
direct calls to ->cmdfunc(). This way, we can easily modify those
helpers to make use of the new ->exec_op() interface when available.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
[miquel.raynal@free-electrons.com: rebased and fixed some conflicts]
Signed-off-by: NMiquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Several drivers check ->chipsize to see if the third row address cycle
is needed.  Instead of embedding magic sizes such as 32MB, 128MB in
drivers, introduce a new flag NAND_ROW_ADDR_3 for clean-up.  Since
nand_scan_ident() knows well about the device, it can handle this
properly.  The flag is set if the row address bit width is greater
than 16.

Delete comments such as "One more address cycle for ..." because
intention is now clear enough from the code.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NWenyou Yang <wenyou.yang@microchip.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

We are planning to share more code between different NAND based
devices (SPI NAND, OneNAND and raw NANDs), but before doing that
we need to move the existing include/linux/mtd/nand.h file into
include/linux/mtd/rawnand.h so we can later create a nand.h header
containing all common structure and function prototypes.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NPeter Pan <peterpandong@micron.com>
Acked-by: NVladimir Zapolskiy <vz@mleia.com>
Acked-by: NAlexander Sverdlin <alexander.sverdlin@gmail.com>
Acked-by: NWenyou Yang <wenyou.yang@microchip.com>
Acked-by: NKrzysztof Kozlowski <krzk@kernel.org>
Acked-by: NHan Xu <han.xu@nxp.com>
Acked-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: NShawn Guo <shawnguo@kernel.org>
Acked-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: NNeil Armstrong <narmstrong@baylibre.com>
Acked-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-By: NHarvey Hunt <harveyhuntnexus@gmail.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Acked-by: NKrzysztof Halasa <khalasa@piap.pl>

Implementing the mtd_ooblayout_ops interface is the new way of exposing
ECC/OOB layout to MTD users.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

One of the arguments passed to struct nand_chip's block_bad op is
'getchip', which, if true, is supposed to get and select the nand device,
and later unselect and release the device.

This op is intended to be replaceable by drivers. The drivers shouldn't
be responsible for selecting/unselecting chip. Like other ops, the chip
should already be selected before the block_bad op is called.

Remove the getchip argument from the block_bad op and
nand_block_checkbad. Move the chip selection to nand_block_isbad, since it
is the only caller to nand_block_checkbad which requires chip selection.

Modify nand_block_bad (the default function for the op) such that it
doesn't select the chip.

Remove the getchip argument from the bad_block funcs in cafe_nand,
diskonchip and docg4 drivers.
Reviewed-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

New helpers have been added to avoid directly accessing chip->field. Use
them where appropriate.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
[Brian: fixed a few rebase conflicts]
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The diskonchip driver is manually checking for 'erased pages' while
correcting ECC bytes.
This logic can now done by the core infrastructure, and can thus be removed
from this driver.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBrian 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: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

struct nand_chip now embeds an mtd device. Make use of this mtd instance.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBrian 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: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Preparation for uniform definition of ioremap, ioremap_wc, ioremap_wt,
and ioremap_cache, tree-wide.
Acked-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

It is a Bad Idea (TM) to call mtd_device_register() or
mtd_device_parse_register() twice on the same master MTD. Among other
things, it makes partition overrides (e.g., cmdlinepart) much more
difficult.

Since commit 727dc612 ("mtd: part: Create the master device node
when partitioned"), we now have a config option that accomplishes the
same purpose as the double-registration done in diskonchip.c -- it
forces the master MTD to *always* be registered, while partitions may
optionally show up in addition. Eventually, we might like to make
CONFIG_MTD_PARTITIONED_MASTER into the default, but this could be
disruptive to user-space expectations of MTD numbering, so we'll take
that slowly.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Alexander Shiyan <shc_work@mail.ru>

The diskonchip driver almost uses the default nand_base hooks as-is,
except that it provides custom on-flash BBT descriptors and avoids using
factory-marked bad blockers.

So let's refactor the BBT initialization code into a private 'late_init'
hook which handles all the private details. Note the usage of
NAND_SKIP_BBTSCAN, which allows us to defer the BBT scan until we've
prepared everything.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>