The fsmc_nand driver uses cpu to read/write onto the device. This is inefficient
because of two reasons
- the cpu gets locked on AHB bus while reading from NAND
- the cpu is unnecessarily used when dma can do the job

This patch adds the support for accessing the device through DMA
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The default way of accessing nand device is using the nand width. This means
that 8bit devices are using u8 * and 16bit devices are accessed using u16 *.

This results in a non-optimal performance since the FSMC is designed to
translate the normal word accesses into device width based accesses. This patch
implements read_buf and write_buf callbacks using word by word accesses.
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

fsmc controller takes time to calculate the bch8 codes and the error offsets.
The calculate logic checks for completion upto a timeout. This patch adds a
error print when this timer expires and the ecc or error offsets are not yet
calculated.
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

fsmc_nand driver currently uses normal kzalloc, request_mem etc routines. This
patch replaces these routines with devm_kzalloc and devm_request_mem_region etc.
Consequently, the error and driver removal scenarios are curtailed.
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

FSMC controllers provide registers to program the required timing values for
attached NAND device. The timing values used until now are relaxed and should
work for all devices.

Although, for read/write performance improvements, the fsmc nand driver should
accept nand timings as a platform data and program the timing parameters into
fsmc registers accordingly.

This patch implements this modification. Additionally, it programs the default
timing parameters if these are not passed via platform data.
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Ideally, the block should have 0xff written on the bad block position. Any value
other than 0xff implies a bad block. In practical situations, there can be
bit flips in the oob area as well which means that a block with 0x7f being read
at bad block position may imply a bad block but it is infact only a bit flip in
the bad block byte.

To resolve this problem, the block is marked as good if number of high bits is
greater than or equal to badblockbits (initialized to 7)
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

ECC can correct up to 8 bits in 512 bytes data + 13 bytes ecc. This means that
the algorithm can correct a max of 8 bits in 4200 bits ie the error indices can
be from 0 to 4199. Of these 0 to 4095 are for data and 4096 to 4199 for ecc.

The driver flips the bit only if the index is <= 4096. This is a bug since the
data bits are only from 0 to 4095.

This patch modifies the check as < 4096
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The ECC logic of FSMC works on 512 bytes data + 13 bytes ECC to generate error
indices of up to 8 incorrect bits. The FSMC driver reads 14 instead of 13 oob
bytes to accommodate for 16 bit device as well.

Unfortunately, the internal ecc state machine gets corrupted for 8 bit devices
reading 512 + 14 bytes of data resulting in error indices not getting reported.

Fix this by reading 14 bytes only for 16 bit devices
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch reimplements the passing of partition information through platform
data. This was unintentionally deleted in commit
0d04eda1
"mtd: fsmc_nand.c: use mtd_device_parse_register"

Artem: fix gcc warning about passin 0 instead of NULL.
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: stable@kernel.org [3.2+]
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch is based on Ville Herva's similar patch to block2mtd.

Trying to pass a parameter through the kernel command line when built-in would
crash the kernel, as phram_setup() was called so early that kmalloc() was not
functional yet.

This patch only saves the parameter string at the early boot stage, and parses
it later when init_phram() is called. The same happens in both module and
built-in cases.

With this patch, I can boot with a statically-compiled phram, and mount a
ext2 root fs from physical RAM, without the need for a initrd.

This has been tested in built-in and module cases, with and without a
parameter string.

Artem: amended comments a bit
Signed-off-by: Hervé Fache <h-fache@ti.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The last DMA command of ECC read page is used to disable the BCH module.
But the original code missed to set the pio[2] which is used to set the
GPMI_HW_GPMI_ECCCTRL register. fix it now.
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>

Flash device drivers initialize 'ecc_strength' in struct mtd_info, which is the
maximum number of bit errors that can be corrected in one writesize region.

Drivers using the nand interface intitialize 'strength' in struct nand_ecc_ctrl,
which is the maximum number of bit errors that can be corrected in one ecc step.
Nand infrastructure code translates this to 'ecc_strength'.

Also for nand drivers, the nand infrastructure code sets ecc.strength for ecc
modes NAND_ECC_SOFT, NAND_ECC_SOFT_BCH, and NAND_ECC_NONE.  It is set in the
driver for all other modes.
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 adds 'ecc_strength' to struct mtd_info.  This stores the maximum number of
bit errors that can be corrected in one writesize region.

For consistency with the nand code, 'strength' is similiarly added to struct
nand_ecc_ctrl.  This stores the maximum number of bit errors that can be
corrected in one ecc step.
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>

The read function was so far requiring the reads to be aligned on page
boundaries, and be page length multiples in size. Relieve these
constraints to ease the userspace ubifs programs runs, which read ubifs
headers of 64 bytes.

Artem: squashed a later fix from Robert Jarzmik into this patch.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Adds power management code with fine granularity. Every flash control
command is enclosed by runtime_put()/get()s. To make sure that no
overhead is generated by too frequent power state switches, a quality of
service request is issued.
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>

The first 3 arguments of 'mtd_device_parse_register()' are pointers,
but many callers pass '0' instead of 'NULL'. Fix this globally. Thanks
to coccinelle for making it easy to do with the following semantic patch:

 @@
 expression mtd, types, parser_data, parts, nr_parts;
 @@
 (
 -mtd_device_parse_register(mtd, 0, parser_data, parts, nr_parts)
 +mtd_device_parse_register(mtd, NULL, parser_data, parts, nr_parts)
 |
 -mtd_device_parse_register(mtd, types, 0, parts, nr_parts)
 +mtd_device_parse_register(mtd, types, NULL, parts, nr_parts)
 |
 -mtd_device_parse_register(mtd, types, parser_data, 0, nr_parts)
 +mtd_device_parse_register(mtd, types, parser_data, NULL, nr_parts)
 )
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch allows sa1100_set_vpp() calls to be nested by adding a reference
counter.
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch allows pcmciamtd_set_vpp() calls to be nested by adding a reference
counter.
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch allows l440gx_set_vpp() calls to be nested by adding a reference
counter.
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch allows physmap_set_vpp() calls to be nested by adding a reference
counter.

omap1_set_vpp() already used a reference counter. Since it is called from
physmap_set_vpp(), omap1_set_vpp() can now be simplified.

simtec_nor_vpp() already disabled hard interrupts. Since it is called from
physmap_set_vpp(), simtec_nor_vpp() can now be simplified.
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch ensures that only those flash operations which call ENABLE_VPP() can
then call DISABLE_VPP(). Other operations should never call DISABLE_VPP().
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch ensures that only those flash operations which call ENABLE_VPP() can
then call DISABLE_VPP(). Other operations should never call DISABLE_VPP().
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The current patch is required to support EVALSPEAR1340CPU
Revision 2 where a new (ONFI compliant) MT29F16G08 NAND
flash from Micron is present.

This NAND flash device defines a OOB area which is
224 bytes long (oobsize).
Signed-off-by: Armando Visconti <armando.visconti@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

This patch improves the error correction routine for bch8
- Loop only up to number of errors detected
- Improve the error index calculation procedure

Additionally, it also renames the "correct" routine to indicate that it is bch8
specific
Signed-off-by: Armando Visconti <armando.visconti@st.com>
Signed-off-by: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Since change_bit() requires a (unsigned int *) as second arg,
the correct definition of err_idx[] array declared as
local variable of fsmc_correct_data() is the following:

	u32 err_idx[8];
Signed-off-by: Armando Visconti <armando.visconti@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Address Latch Enable (ALE) and Command Latch Enable (CLE) defines are
platform specific and were wrongly put in driver specific fsmc.h file.
Move such defines to their respective platform.

Also instead of relying on fsmc driver, pass ALE, CLE offsets explicitly
from individual platform.
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

ALE and CLE offsets can be different on different devices. Let devices
pass these offsets to the fsmc driver through platform data.
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

ECC1 & ECC4 layout for NAND of different pages sizes for e.g. 512bytes,
2KiB, 4KiB and 8KiB are separated. Previously there existed one ECC4
layout for 2KiB & 4KiB page size due to which oob test module available
in drivers/mtd/nand/test was failing.
Signed-off-by: Bhavna Yadav <bhavna.yadav@st.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

A newly erased page contains ff in data as well as spare area. While reading an
erased page, the read out ecc from spare area does not match the ecc generated
by fsmc ecc hardware accelerator. This is because ecc of data ff ff is not ff
ff. This leads to errors when file system erases and reads back the pages to
ensure consistency.

This patch adds a software workaround to ensure that the ecc check is not
performed for erased pages. This problem is solved by checking the number of
bits (in 512 byte data + 13 byte ecc) which are 0. If these number of bits are
less than 8, the page is considered erased and correction algorithm is not tried
on that page
Signed-off-by: Vipin Kumar <vipin.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>

This patch reverts a change that may have been mistakenly included with the set
of patches that introduced the new mtd api entry functions.  Or perhaps I am
mistaken :)

The problem is in the partition wrapper functions, where the calls to the driver
methods were replaced with calls to the new mtd api functions.  This causes the
api function to be called a second time, further down the call stack.  This is
not only unnecessary and redundant - because the sanity checking code and (more
restrictive) bounds checks for the partition were done in the first call - but
is potentially problematic and confusing.

For example, the call stack for a call to mtd_read() on a partitioned device
currently looks like this:

mtd_read()             gets struct mtd_info for the partition
|
+-> part_read()        via the pointer assigned when the partition was created
    |
    +->mtd_read()      this time gets struct mtd_info for the master
       |
       +->xyz_driver_read()  via the pointer asigned by the driver

It seems that this can cause a variety of problems.  For example, if you want to
add code to the api function that tests a value in mtd_info that is relevant
only to the partition.  Or (in my case) you want the driver to return a value
that may be different from that returned by the mtd api function.

This patch eliminates the second call to the mtd api function.  It was tested on
the docg4 nand driver with a subset of the api functions, but I inspected the
rest and don't see any problems.
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>

Change the name of the mtd so that it is simpler, and is easier to
cope with by mtdparts.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Add board and clock setup code for the SH Mobile flctl controller.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Add a register used in new FLCTL hardware and a feature flag for it.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Instead of reading out the register, use a cached value. This will
make way for a proper runtime power management implementation.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Implements the command to seek and read in pages.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The nand base code wants to read out 8 bytes in the READID command.
Reflect this in the driver code.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Reorders the calls to make it a bit shorter and match the calling
procedure displayed in the datasheet.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>