The drivers' _read() method, absent an error, returns a non-negative integer
indicating the maximum number of bit errors that were corrected in any one
region comprising an ecc step.  MTD returns -EUCLEAN if this is >=
bitflip_threshold, 0 otherwise.  If bitflip_threshold is zero, the comparison is
not made since these devices lack ECC and always return zero in the non-error
case (thanks Brian)¹.  Note that this is a subtle change to the driver
interface.

This and the preceding patches in this set were tested with ubi on top of the
nandsim and docg4 devices, running the ubi test io_basic from mtd-utils.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-March/040468.htmlSigned-off-by: Mike Dunn <mikedunn@newsguy.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Ivan Djelic <ivan.djelic@parrot.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch adds sanity checks that ensure that drivers for controllers with
hardware ECC set the 'strength' element in struct nand_ecc_ctrl.  Also stylistic
changes to the line that calculates strength for software ECC.

This v2 simplifies the check.  Thanks Brian!¹

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-April/040890.htmlSigned-off-by: Mike Dunn <mikedunn@newsguy.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The ecc.read_page() method for nand drivers is changed to return the maximum
number of bitflips that were corrected on any one region covering an ecc step,
This patch doesn't change what the nand code returns to mtd.

This v2 includes the change to the fsl_ifc_nand driver requested by Scott¹.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-April/040883.htmlSigned-off-by: Mike Dunn <mikedunn@newsguy.com>
Acked-by (freescale changes): Scott Wood <scottwood@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

An element 'bitflip_threshold' is added to struct mtd_info, and also exposed as
a read/write variable in sysfs.  This will be used to determine whether or not
mtd_read() returns -EUCLEAN or 0 (absent a hard error).  If the driver leaves it
as zero, mtd will set it to a default value of ecc_strength.

This v2 adds the line that propagates bitflip_threshold from the master to the
partitions - thanks Ivan¹.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-April/040900.htmlSigned-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

ecc_strength element of struct mtd_info is exposed as a read-only variable in
sysfs.
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This fixes a couple of ecc strength values for which I earlier made conservative
guesses, but whose correct values were later determined¹ (thanks Ivan).  Also
sets strength for fsl_ifc_nand, which was merged to mainline after the original
patch that set the strength for all drivers.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-March/040325.htmlSigned-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

ecc_strength element of mtd_info will be the strength of one ecc step, not of
the entire writesize, as was previously planned.  This is the appropriate way
because, as was pointed out¹, bit errors in excess of the strength of one
step can cause a hard error if they all occur within the same ecc region.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-March/040313.htmlSigned-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

To make sure the NAND chip is properly programmed we need a status
command before each page write. When CONFIG_MTD_NAND_VERIFY_WRITE=y this
assumption is broken when writing multiple pages consecutively. This
patch fixes this.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Replace the verbose `je32_to_cpu(latest_node->csize)' with a shorter
`csize'.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

`csize' is read from disk and thus needs validation.  Otherwise a bogus
value 0xffffffff would turn the subsequent kmalloc(csize + 1, ...) into
kmalloc(0, ...), leading to out-of-bounds write.

This patch limits `csize' to JFFS2_MAX_NAME_LEN, which is also used
in jffs2_symlink().

Artem: we actually validate csize by checking CRC, so this 0xFFs cannot
come from empty flash region. But I guess an attacker could feed JFFS2
an image with random csize value, including 0xFFs.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Peter Meerwald <p.meerwald@bct-electronic.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This is tested on i.MX27.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This gets rid of one more nfc_is_vX().
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This commit makes problems on v1 and v2 regarding 4KiBpages more obvious.
As I don't have a 4KiB flash handy I just keep the status quo.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This prepares switching to platform ids and of-tree probing.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This gets rid of several instances of cpu_is_mx21() in the driver.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

page_read() never returns NULL, so we can remove the NULL check here.
Signed-off-by: Ryosuke Saito <raitosyo@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The original Broadcom partition order has the root fs in front of the
kernel, which resulted in miscalculated partition sizes.
Detect when such an image is on the flash and also reorder the partitions
accordingly.
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

If a context switch occurs in function omap_wait() just before the
while loop is entered, then upon return from context switch the
timeout may already have elapsed: in that case, status is never
read from NAND device, and omap_wait() returns an error.
This failure has been experimentally observed during stress tests.

This patch ensures a NAND status read is always performed before
returning, as in the generic nand_wait() function.
Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

clk_{un}prepare is mandatory for platforms using common clock framework. Since
this driver is used by SPEAr platform, which supports common clock framework,
add clk_{un}prepare() support for it.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

clk_{un}prepare is mandatory for platforms using common clock framework. Since
this driver is used by SPEAr platform, which supports common clock framework,
add clk_{un}prepare() support for it.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

scb2_flash.c is a PCI driver, but its build fails when CONFIG_PCI
is not enabled, so make it depend on PCI.

drivers/mtd/maps/scb2_flash.c:237:1: warning: data definition has no type or storage class
drivers/mtd/maps/scb2_flash.c:237:1: warning: type defaults to 'int' in declaration of 'module_pci_driver'
drivers/mtd/maps/scb2_flash.c:237:1: warning: parameter names (without types) in function declaration
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

If prefetch engine is busy, current code "forgets" to call
dma_unmap_single(), which results in a deadlock later, so add it.
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Add a new rp_size= parameter which creates a "reserved pool" of disk
space which can only be used by root. Other users are not permitted
to write to disk when the available space is less than the pool size.

Based on original code by Artem Bityutskiy in
https://dev.laptop.org/ticket/5317

[dwmw2: use capable(CAP_SYS_RESOURCE) not uid/gid check, fix debug prints]
Signed-off-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Some not-supported nand chips may pass the current parsing code,
and get the wrong page size and oob size. Sometimes, it's hard to notice
that you get the wrong values, because there is no warning or error.

So it's useful to print out the page size and oob size in the end of
the parsing function. We can check these values with the datasheet of the nand
chip as soon as possible.

Artem: amend the print a bit
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

  - Fix NAND_CMD_READID command for ONFI detect.
  - Add NAND_CMD_PARAM command to read the ONFI parameter page.
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch converts the drivers in drivers/mtd/* to use module_pci_driver()
macro which makes the code smaller and a bit simpler.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The mxs.h does not exit in the mx6q.
So rewrite the __mxs_clrl()/__mxs_setl() and remove the mxs.h.
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

As long as there is no other non-const variable marked __initdata in the
same compilation unit it doesn't hurt. If there were one however
compilation would fail with

	error: $variablename causes a section type conflict

because a section containing const variables is marked read only and so
cannot contain non-const variables.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Use the default partition parser, cmdlinepart, provided by the plat_nand driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Use the default partition parser, cmdlinepart, provided by the plat_nand driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Use the default partition parser, cmdlinepart, provided by the plat_nand driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Use the default partition parser, cmdlinepart, provided by the plat_nand driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Alexander Clouter <alex@digriz.org.uk>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>