Commit Graph

4184 Commits

Author SHA1 Message Date
Huang Shijie
bd92029cdb mtd: gpmi: remove the unused line
We do not use the chip->oob_poi in the mx23_write_transcription_stamp.
So remove the unused line.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:18 -08:00
Huang Shijie
d7364a2710 mtd: gpmi: delete the gpmi_pre_bbt_scan
We do not scan the BBT after we call the gpmi_pre_bbt_scan,
so it has lost the meaning of existence.

This patch merges this function into gpmi_init_last, and delete it.
This patch does not change any logic.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:18 -08:00
Huang Shijie
df877fb3f5 mtd: gpmi: do not use the local array to do the DMA transfer
The local array feature[] is in the stack. We can see the warning
when we enable the CONFIG_DMA_API_DEBUG:
----------------------------------------------------------
WARNING: at lib/dma-debug.c:950 check_for_stack+0xac/0xf8()
gpmi-nand 112000.gpmi-nand: DMA-API: device driver maps memory fromstack [addr=dc05be34]
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.17-16851-g2414a73 #1324
[<80014cbc>] (unwind_backtrace+0x0/0x138) from [<8001251c>] (show_stack+0x10/0x14)
[<8001251c>] (show_stack+0x10/0x14) from [<8002699c>] (warn_slowpath_common+0x4c/0x68)
[<8002699c>] (warn_slowpath_common+0x4c/0x68) from [<80026a4c>] (warn_slowpath_fmt+0x30/0x40)
[<80026a4c>] (warn_slowpath_fmt+0x30/0x40) from [<8028e2f8>] (check_for_stack+0xac/0xf8)
[<8028e2f8>] (check_for_stack+0xac/0xf8) from [<8028e438>] (debug_dma_map_sg+0xf4/0x188)
[<8028e438>] (debug_dma_map_sg+0xf4/0x188) from [<803968d0>] (prepare_data_dma+0xb8/0x1a8)
[<803968d0>] (prepare_data_dma+0xb8/0x1a8) from [<80397b20>] (gpmi_send_data+0x84/0xfc)
[<80397b20>] (gpmi_send_data+0x84/0xfc) from [<8038c2b4>] (nand_onfi_set_features+0x50/0x74)
[<8038c2b4>] (nand_onfi_set_features+0x50/0x74) from [<80397198>] (gpmi_extra_init+0x90/0x170)
[<80397198>] (gpmi_extra_init+0x90/0x170) from [<8039520c>] (gpmi_nand_probe+0x2f8/0xb3c)
[<8039520c>] (gpmi_nand_probe+0x2f8/0xb3c) from [<8031b974>] (platform_drv_probe+0x18/0x1c)
----------------------------------------------------------

The patch uses the kzalloc to allocate the buffer, and free it when
we do not use it anymore.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:18 -08:00
Brian Norris
6033a949b2 mtd: nand: pxa3xx: make ECC configuration checks more explicit
The Armada BCH configuration in this driver uses one of the two
following ECC schemes:

 16-bit correction per 2048 bytes
 16-bit correction per 1024 bytes

These are sufficient for mapping to the 4-bit per 512-bytes and 8-bit
per 512-bytes (respectively) minimum correctability requirements of many
common NAND.

The current code only checks for the required strength (4-bit or 8-bit)
without checking the ECC step size that is associated with that strength
(and simply assumes it is 512). While that is often a safe assumption to
make, let's make it explicit, since we have that information.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
2014-01-03 11:22:18 -08:00
Ezequiel Garcia
87f5336eef mtd: nand: pxa3xx: Add ECC BCH correctable errors detection
This commit extends the ECC correctable error detection to include
ECC BCH errors. The number of BCH correctable errors can be any up to 16,
and the actual value is exposed in the NDSR register.

Therefore, we change some symbol names to refer to correctable or
uncorrectable (instead of single-bit or double-bit as it was in the
Hamming case) and while at it, cleanup the detection code slightly.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:17 -08:00
Ezequiel Garcia
535cb57a4d mtd: nand: pxa3xx: Add multiple chunk write support
This commit adds write support for large pages (4 KiB, 8 KiB).
Such support is implemented by issuing a multiple command sequence,
transfering a set of 2 KiB chunks per transaction.

The splitted command sequence requires to send the SEQIN command
independently of the PAGEPROG command and therefore it's set as
an execution command.

Since PAGEPROG enables ECC, each 2 KiB chunk of data is written
together with ECC code at a controller-fixed location within
the flash page.

Currently, only devices with a 4 KiB page size has been tested.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:17 -08:00
Ezequiel Garcia
70ed85232a mtd: nand: pxa3xx: Introduce multiple page I/O support
As preparation work to fully support large pages, this commit adds
the initial infrastructure to support splitted (aka chunked) I/O
operation. This commit adds support for read, and follow-up patches
will add write support.

When a read (aka READ0) command is issued, the driver loops issuing
the same command until all the requested data is transfered, changing
the 'extended' command field as needed.

For instance, if the driver is required to read a 4 KiB page, using a
chunk size of 2 KiB, the transaction is splitted in:
1. Monolithic read, first 2 KiB page chunk is read
2. Last naked read, second and last 2KiB page chunk is read

If ECC is enabled it is calculated on each chunk transfered and added
at a controller-fixed location after the data chunk that must be
spare area.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:17 -08:00
Ezequiel Garcia
fa543bef72 mtd: nand: pxa3xx: Add a read/write buffers markers
In preparation to support multiple (aka chunked, aka splitted)
page I/O, this commit adds 'data_buff_pos' and 'oob_buff_pos' fields
to keep track of where the next read (or write) should be done.

This will allow multiple calls to handle_data_pio() to continue
the read (or write) operation.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:17 -08:00
Ezequiel Garcia
e7f9a6a462 mtd: nand: pxa3xx: Fix SEQIN column address set
This commit adds support page programming with a non-zero "column"
address setting. This is important to support OOB writing, through
command sequences such as:

  cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, ofs);
  write_buf(mtd, oob_buf, 6);
  cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:16 -08:00
Ezequiel Garcia
39f83d15df mtd: nand: pxa3xx: Move the data buffer clean to prepare_start_command()
To allow future support of multiple page reading/writing, move the data
buffer clean out of prepare_set_command().

This is done to prevent the data buffer from being cleaned on every command
preparation, when a multiple command sequence is implemented to read/write
pages larger than the FIFO size (2 KiB).

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:13 -08:00
Ezequiel Garcia
c39ff03a40 mtd: nand: pxa3xx: Split prepare_command_pool() in two stages
This commit splits the prepare_command_pool() function into two
stages: prepare_start_command() / prepare_set_command().

This is a preparation patch without any functionality changes,
and is meant to allow support for multiple page reading/writing
operations.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:13 -08:00
Ezequiel Garcia
01d9947e04 mtd: nand: pxa3xx: Remove READ0 switch/case falltrough
READ0 and READOOB command preparation has a falltrough to SEQIN
case, where the command address is specified.
This is certainly confusing and makes the code less readable with
no added value. Let's remove it.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:12 -08:00
Ezequiel Garcia
86beebae3a mtd: nand: pxa3xx: Add helper function to set page address
Let's simplify the code by first introducing a helper function
to set the page address, as done by the READ0, READOOB and SEQIN
commands.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:12 -08:00
Ezequiel Garcia
f0e6a32e9a mtd: nand: pxa3xx: Clear cmd buffer #3 (NDCB3) on command start
Command buffer #3 is not properly cleared and it keeps the last
set value. Fix this by clearing when a command is setup.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:12 -08:00
Ezequiel Garcia
43bcfd2bb2 mtd: nand: pxa3xx: Add driver-specific ECC BCH support
This commit adds the BCH ECC support available in NFCv2 controller.
Depending on the detected required strength the respective ECC layout
is selected.

This commit adds an empty ECC layout, since support to access large
pages is first required. Once that support is added, a proper ECC
layout will be added as well.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:12 -08:00
Ezequiel Garcia
776f265e27 mtd: nand: pxa3xx: Add bad block handling
Add support for flash-based bad block table using Marvell's
custom in-flash bad block table layout. The support is enabled
a 'flash_bbt' platform data or device tree parameter.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:12 -08:00
Ezequiel Garcia
56704d857a mtd: nand: pxa3xx: Use waitfunc() to wait for the device to be ready
In pxa3xx_nand_sensing() instead of simply using info->is_ready
after issuing a command, the correct way of checking is to wait
for the device to be ready through the chip's waitfunc().

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:11 -08:00
Ezequiel Garcia
55d9fd6e94 mtd: nand: pxa3xx: Use a completion to signal device ready
The expected behavior of the waitfunc() NAND chip call is to wait
for the device to be READY (this is a standard chip line).
However, the current implementation does almost nothing, which opens
the possibility of issuing a command to a non-ready device.

Fix this by adding a new completion to wait for the ready event to arrive.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:11 -08:00
Ezequiel Garcia
6a3e48651f mtd: nand: pxa3xx: Add a nice comment to pxa3xx_set_datasize()
Add a comment clarifying the use of pxa3xx_set_datasize() which is only
applicable on data read/write commands (i.e. commands with a data cycle,
such as READID, READ0, STATUS, etc.)

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:11 -08:00
Ezequiel Garcia
0a3f3a1916 mtd: nand: pxa3xx: Replace host->page_size by mtd->writesize
There's no need to privately store the device page size as it's
available in mtd structure field mtd->writesize.
Also, this removes the hardcoded page size value, leaving the
auto-detected value only.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:11 -08:00
Ezequiel Garcia
2128b08c7c mtd: nand: pxa3xx: Split FIFO size from to-be-read FIFO count
Introduce a fifo_size field to represent the size of the controller's
FIFO buffer, and use it to distinguish that size from the amount
of data bytes to be read from the FIFO.

This is important to support devices with pages larger than the
controller's internal FIFO, that need to read the pages in FIFO-sized
chunks.

In particular, the current code is at least confusing, for it mixes
all the different sizes involved: FIFO size, page size and data size.

This commit starts the cleaning by removing the info->page_size field
that is not currently used. The host->page_size field should also
be removed and use always mtd->writesize instead. Follow up commits
will clean this up.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:11 -08:00
Ezequiel Garcia
2d79ab16f5 mtd: nand: pxa3xx: Use chip->cmdfunc instead of the internal
Whenever possible, it's always better to use the generic chip->cmdfunc
instead of the internal pxa3xx_nand_cmdfunc().
In this particular case, this will allow to have multiple cmdfunc()
implementations for different SoC variants.

Reviewed-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:10 -08:00
Ezequiel Garcia
c7e9c7e71b mtd: nand: pxa3xx: Early variant detection
In order to customize early settings depending on the detected SoC variant,
move the detection to be before the nand_chip struct filling.

In a follow-up patch, this change is needed to detect the variant *before*
the call to alloc_nand_resource(), which allows to set a different cmdfunc()
for each variant.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:10 -08:00
Ezequiel Garcia
4e86fd22af mtd: nand: pxa3xx: read_page() returns max_bitflips
As per the ecc.read_page() prototype, we must return the maximum number
of bitflips that were corrected on any one region covering an ecc step.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:10 -08:00
Ezequiel Garcia
664c7f5e81 mtd: nand: pxa3xx: Prevent sub-page writes
The current driver doesn't support sub-page writing, so report
that to the NAND core.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:10 -08:00
Ezequiel Garcia
c5f99677a4 mtd: nand: pxa3xx: Make config menu show supported platforms
Since we have now support for the NFCv2 controller found on
Armada 370/XP platforms.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:10 -08:00
Ezequiel Garcia
de484a381c mtd: nand: pxa3xx: Add documentation about the controller
Given there's no public specification to this date, and in order
to capture some important details and singularities about the
controller let's document them once and for good.

Cc: linux-doc@vger.kernel.org
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:09 -08:00
Geert Uytterhoeven
26a6d240e2 mtd: make mtd_partition.name const
This allows to drop a few casts.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:09 -08:00
Geert Uytterhoeven
da6fcf0e37 mtd: ms02-nv: remove superfluous name cast
mtd_info.name is "const char *"

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:09 -08:00
Geert Uytterhoeven
8ca14e12a7 mtd: pasemi_nand.c: remove superfluous name cast
device_driver.name is "const char *"

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Olof Johansson <olof@lixom.net>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:09 -08:00
Geert Uytterhoeven
7c4bb4f8f8 mtd: remove superfluous name casts
map_info.name is "const char *"

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:08 -08:00
Fabio Estevam
76c930be3d mtd: gpmi-lib: Make checkpatch happy
Fix the following checkpatch warnings:

WARNING: line over 80 characters
#268: FILE: mtd/nand/gpmi-nand/gpmi-lib.c:268:
+	* consecutive reboots. The latter case has not been seen on the MX23 yet,

WARNING: space prohibited before semicolon
#356: FILE: mtd/nand/gpmi-nand/gpmi-lib.c:356:
+		(target.tRHOH_in_ns >= 0) ;

WARNING: space prohibited before semicolon
#1006: FILE: mtd/nand/gpmi-nand/gpmi-lib.c:1006:
+		BF_GPMI_TIMING0_DATA_SETUP(hw.data_setup_in_cycles)       ;

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:08 -08:00
Fabio Estevam
554cbc509f mtd: gpmi: Use devm_clk_get()
Using devm_clk_get() can make the code smaller and cleaner.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:08 -08:00
Huang Shijie
89b59e6cc1 mtd: gpmi: add a new DT property to use the datasheet's minimum required ECC
In default way, we use the ecc_strength/ecc_step size calculated by ourselves
and use all the OOB area.

This patch adds a new property : "fsl,use-minimum-ecc"

If we enable it, we will firstly try to use the datasheet's minimum required
ECC provided by the MTD layer (the ecc_strength_ds/ecc_step_ds fields
in the nand_chip{}). So we may have free space in the OOB area by using the
minimum ECC, and we may support JFFS2 with some SLC NANDs, such as Micron's
SLC NAND.

If we fail to use the minimum ECC, we will use the legacy method to calculate
the ecc_strength and ecc_step size.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:08 -08:00
Ezequiel Garcia
43b77693be mtd: nand: omap2: Fix OMAP_BCH option dependency
This option does not need to depend in MTD_NAND, for it's enclosed
under it. Also, it's wrong to make it depend in ARCH_OMAP3 only
since the controller is used in a wider range of SoCs.

Instead, just leave the dependency on the OMAP2 driver option.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Acked-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:08 -08:00
Sourav Poddar
3487a63955 drivers: mtd: m25p80: add quad read support
Some flash also support quad read mode. Adding support for quad read
mode in m25p80 for Spansion and Macronix flash.

[Tweaked by Brian]

With this patch, quad-read support will override fast-read and
normal-read, if the SPI controller and flash chip both support it.

Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:07 -08:00
Sourav Poddar
8552b439ab drivers: mtd: m25p80: convert "bool" read check into an enum
This is a cleanup prior to adding quad read support. This will facilitate
easy addition of more read commands check under an enum rather that defining a
separate bool for it.

Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:07 -08:00
Ezequiel Garcia
15b540c71c mtd: nand: pxa3xx: Use info->use_dma to release DMA resources
In commit:

  commit 62e8b85178
  Author: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
  Date:   Fri Oct 4 15:30:38 2013 -0300

  mtd: nand: pxa3xx: Allocate data buffer on detected flash size

the way the buffer is allocated was changed: the first READ_ID is issued
with a small kmalloc'ed buffer. Only once the flash page size is detected
the DMA buffers are allocated, and info->use_dma is set.

Currently, if the device detection fails, the driver checks the 'use_dma'
module parameter and tries to release unallocated DMA resources.

Fix this by checking the proper indicator of the DMA allocation, which
is 'info->use_dma'.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-12-12 15:02:04 -08:00
Ezequiel Garcia
9c59ac6161 Partially revert "mtd: nand: pxa3xx: Introduce 'marvell,armada370-nand' compatible string"
This partially reverts c0f3b8643a.

The "armada370-nand" compatible support is not complete, and it was mistake
to add it. Revert it and postpone the support until the infrastructure is
in place.

Cc: <stable@vger.kernel.org> # 3.12
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-12-12 15:01:30 -08:00
Linus Torvalds
e6d69a60b7 Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
Pull slave-dmaengine changes from Vinod Koul:
 "This brings for slave dmaengine:

   - Change dma notification flag to DMA_COMPLETE from DMA_SUCCESS as
     dmaengine can only transfer and not verify validaty of dma
     transfers

   - Bunch of fixes across drivers:

      - cppi41 driver fixes from Daniel

      - 8 channel freescale dma engine support and updated bindings from
        Hongbo

      - msx-dma fixes and cleanup by Markus

   - DMAengine updates from Dan:

      - Bartlomiej and Dan finalized a rework of the dma address unmap
        implementation.

      - In the course of testing 1/ a collection of enhancements to
        dmatest fell out.  Notably basic performance statistics, and
        fixed / enhanced test control through new module parameters
        'run', 'wait', 'noverify', and 'verbose'.  Thanks to Andriy and
        Linus [Walleij] for their review.

      - Testing the raid related corner cases of 1/ triggered bugs in
        the recently added 16-source operation support in the ioatdma
        driver.

      - Some minor fixes / cleanups to mv_xor and ioatdma"

* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (99 commits)
  dma: mv_xor: Fix mis-usage of mmio 'base' and 'high_base' registers
  dma: mv_xor: Remove unneeded NULL address check
  ioat: fix ioat3_irq_reinit
  ioat: kill msix_single_vector support
  raid6test: add new corner case for ioatdma driver
  ioatdma: clean up sed pool kmem_cache
  ioatdma: fix selection of 16 vs 8 source path
  ioatdma: fix sed pool selection
  ioatdma: Fix bug in selftest after removal of DMA_MEMSET.
  dmatest: verbose mode
  dmatest: convert to dmaengine_unmap_data
  dmatest: add a 'wait' parameter
  dmatest: add basic performance metrics
  dmatest: add support for skipping verification and random data setup
  dmatest: use pseudo random numbers
  dmatest: support xor-only, or pq-only channels in tests
  dmatest: restore ability to start test at module load and init
  dmatest: cleanup redundant "dmatest: " prefixes
  dmatest: replace stored results mechanism, with uniform messages
  Revert "dmatest: append verify result to results"
  ...
2013-11-20 13:20:24 -08:00
Vinod Koul
df12a3178d Merge commit 'dmaengine-3.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine
Pull dmaengine changes from Dan

1/ Bartlomiej and Dan finalized a rework of the dma address unmap
   implementation.

2/ In the course of testing 1/ a collection of enhancements to dmatest
   fell out.  Notably basic performance statistics, and fixed / enhanced
   test control through new module parameters 'run', 'wait', 'noverify',
   and 'verbose'.  Thanks to Andriy and Linus for their review.

3/ Testing the raid related corner cases of 1/ triggered bugs in the
   recently added 16-source operation support in the ioatdma driver.

4/ Some minor fixes / cleanups to mv_xor and ioatdma.

Conflicts:
	drivers/dma/dmatest.c

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-11-16 12:02:36 +05:30
Linus Torvalds
9073e1a804 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "Usual earth-shaking, news-breaking, rocket science pile from
  trivial.git"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
  doc: add missing files to timers/00-INDEX
  timekeeping: Fix some trivial typos in comments
  mm: Fix some trivial typos in comments
  irq: Fix some trivial typos in comments
  NUMA: fix typos in Kconfig help text
  mm: update 00-INDEX
  doc: Documentation/DMA-attributes.txt fix typo
  DRM: comment: `halve' -> `half'
  Docs: Kconfig: `devlopers' -> `developers'
  doc: typo on word accounting in kprobes.c in mutliple architectures
  treewide: fix "usefull" typo
  treewide: fix "distingush" typo
  mm/Kconfig: Grammar s/an/a/
  kexec: Typo s/the/then/
  Documentation/kvm: Update cpuid documentation for steal time and pv eoi
  treewide: Fix common typo in "identify"
  __page_to_pfn: Fix typo in comment
  Correct some typos for word frequency
  clk: fixed-factor: Fix a trivial typo
  ...
2013-11-15 16:47:22 -08:00
Wolfram Sang
16735d022f tree-wide: use reinit_completion instead of INIT_COMPLETION
Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 09:32:21 +09:00
Bartlomiej Zolnierkiewicz
0776ae7b89 dmaengine: remove DMA unmap flags
Remove no longer needed DMA unmap flags:
- DMA_COMPL_SKIP_SRC_UNMAP
- DMA_COMPL_SKIP_DEST_UNMAP
- DMA_COMPL_SRC_UNMAP_SINGLE
- DMA_COMPL_DEST_UNMAP_SINGLE

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Jon Mason <jon.mason@intel.com>
Acked-by: Mark Brown <broonie@linaro.org>
[djbw: clean up straggling skip unmap flags in ntb]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2013-11-14 11:04:38 -08:00
Linus Torvalds
82cb6acea4 MTD merge for 3.13
* Unify some compile-time differences so that we have fewer uses of
    #ifdef CONFIG_OF in atmel_nand
  * Other general cleanups (removing unused functions, options, variables,
    fields; use correct interfaces)
  * Fix BUG() for new odd-sized NAND, which report non-power-of-2 dimensions via
    ONFI
  * Miscellaneous driver fixes (SPI NOR flash; BCM47xx NAND flash; etc.)
  * Improve differentiation between SLC and MLC NAND -- this clarifies an ABI
    issue regarding the MTD "type" (in sysfs and in ioctl(MEMGETINFO)), where
    the MTD_MLCNANDFLASH type was present but inconsistently used
  * Extend GPMI NAND to support multi-chip-select NAND for some platforms
  * Many improvements to the OMAP2/3 NAND driver, including an expanded DT
    binding to bring us closer to mainline support for some OMAP systems
  * Fix a deadlock in the error path of the Atmel NAND driver probe
  * Correct the error codes from MTD mmap() to conform to POSIX and the Linux
    Programmer's Manual. This is an acknowledged change in the MTD ABI, but I
    can't imagine somebody relying on the non-standard -ENOSYS error code
    specifically. Am I just being unimaginative? :)
  * Fix a few important GPMI NAND bugs (one regression from 3.12 and one
    long-standing race condition)
  * More? Read the log!
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Merge tag 'for-linus-20131112' of git://git.infradead.org/linux-mtd

Pull MTD changes from Brian Norris:
 - Unify some compile-time differences so that we have fewer uses of
   #ifdef CONFIG_OF in atmel_nand
 - Other general cleanups (removing unused functions, options,
   variables, fields; use correct interfaces)
 - Fix BUG() for new odd-sized NAND, which report non-power-of-2
   dimensions via ONFI
 - Miscellaneous driver fixes (SPI NOR flash; BCM47xx NAND flash; etc.)
 - Improve differentiation between SLC and MLC NAND -- this clarifies an
   ABI issue regarding the MTD "type" (in sysfs and in the MEMGETINFO
   ioctl), where the MTD_MLCNANDFLASH type was present but
   inconsistently used
 - Extend GPMI NAND to support multi-chip-select NAND for some platforms
 - Many improvements to the OMAP2/3 NAND driver, including an expanded
   DT binding to bring us closer to mainline support for some OMAP
   systems
 - Fix a deadlock in the error path of the Atmel NAND driver probe
 - Correct the error codes from MTD mmap() to conform to POSIX and the
   Linux Programmer's Manual.  This is an acknowledged change in the MTD
   ABI, but I can't imagine somebody relying on the non-standard -ENOSYS
   error code specifically.  Am I just being unimaginative? :)
 - Fix a few important GPMI NAND bugs (one regression from 3.12 and one
   long-standing race condition)
 - More? Read the log!

* tag 'for-linus-20131112' of git://git.infradead.org/linux-mtd: (98 commits)
  mtd: gpmi: fix the NULL pointer
  mtd: gpmi: fix kernel BUG due to racing DMA operations
  mtd: mtdchar: return expected errors on mmap() call
  mtd: gpmi: only scan two chips for imx6
  mtd: gpmi: Use devm_kzalloc()
  mtd: atmel_nand: fix bug driver will in a dead lock if no nand detected
  mtd: nand: use a local variable to simplify the nand_scan_tail
  mtd: nand: remove deprecated IRQF_DISABLED
  mtd: dataflash: Say if we find a device we don't support
  mtd: nand: omap: fix error return code in omap_nand_probe()
  mtd: nand_bbt: kill NAND_BBT_SCANALLPAGES
  mtd: m25p80: fixup device removal failure path
  mtd: mxc_nand: Include linux/of.h header
  mtd: remove duplicated include from mtdcore.c
  mtd: m25p80: add support for Macronix mx25l3255e
  mtd: nand: omap: remove selection of BCH ecc-scheme via KConfig
  mtd: nand: omap: updated devm_xx for all resource allocation and free calls
  mtd: nand: omap: use drivers/mtd/nand/nand_bch.c wrapper for BCH ECC instead of lib/bch.c
  mtd: nand: omap: clean-up ecc layout for BCH ecc schemes
  mtd: nand: omap2: clean-up BCHx_HW and BCHx_SW ECC configurations in device_probe
  ...
2013-11-14 12:31:43 +09:00
Linus Torvalds
9bc9ccd7db Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "All kinds of stuff this time around; some more notable parts:

   - RCU'd vfsmounts handling
   - new primitives for coredump handling
   - files_lock is gone
   - Bruce's delegations handling series
   - exportfs fixes

  plus misc stuff all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
  ecryptfs: ->f_op is never NULL
  locks: break delegations on any attribute modification
  locks: break delegations on link
  locks: break delegations on rename
  locks: helper functions for delegation breaking
  locks: break delegations on unlink
  namei: minor vfs_unlink cleanup
  locks: implement delegations
  locks: introduce new FL_DELEG lock flag
  vfs: take i_mutex on renamed file
  vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
  vfs: don't use PARENT/CHILD lock classes for non-directories
  vfs: pull ext4's double-i_mutex-locking into common code
  exportfs: fix quadratic behavior in filehandle lookup
  exportfs: better variable name
  exportfs: move most of reconnect_path to helper function
  exportfs: eliminate unused "noprogress" counter
  exportfs: stop retrying once we race with rename/remove
  exportfs: clear DISCONNECTED on all parents sooner
  exportfs: more detailed comment for path_reconnect
  ...
2013-11-13 15:34:18 +09:00
Linus Torvalds
39222c82f7 A bunch of fixes for the fastmap feature, which is still new and rather
experimental. It looks like it starts getting more users. No significant
 changes for the "classical" non-fastmap UBI.
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Merge tag 'upstream-3.13-rc1' of git://git.infradead.org/linux-ubi

Pull UBI changes from Artem Bityutskiy:
 "A bunch of fixes for the fastmap feature, which is still new and
  rather experimental.  It looks like it starts getting more users.

  No significant changes for the "classical" non-fastmap UBI"

* tag 'upstream-3.13-rc1' of git://git.infradead.org/linux-ubi:
  UBI: Add some asserts to ubi_attach_fastmap()
  UBI: Fix memory leak in ubi_attach_fastmap() error path
  UBI: simplify image sequence test
  UBI: fastmap: fix backward compatibility with image_seq
  UBI: Call scan_all() with correct offset in error case
  UBI: Fix error path in scan_pool()
  UBI: fix refill_wl_user_pool()
2013-11-13 15:29:38 +09:00
Huang Shijie
885d71e583 mtd: gpmi: fix the NULL pointer
The imx23 board will check the fingerprint, so it will call the
mx23_check_transcription_stamp. This function will use @chip->buffers->databuf
as its buffer which is allocated in the nand_scan_tail().

Unfortunately, the mx23_check_transcription_stamp is called before the
nand_scan_tail(). So we will meet a NULL pointer bug:

--------------------------------------------------------------------
[    1.150000] NAND device: Manufacturer ID: 0xec, Chip ID: 0xd7 (Samsung NAND 4GiB 3,3V 8-bit), 4096MiB, page size: 4096, OOB size: 8
[    1.160000] Unable to handle kernel NULL pointer dereference at virtual address 000005d0
[    1.170000] pgd = c0004000
[    1.170000] [000005d0] *pgd=00000000
[    1.180000] Internal error: Oops: 5 [#1] ARM
[    1.180000] Modules linked in:
[    1.180000] CPU: 0 PID: 1 Comm: swapper Not tainted 3.12.0 #89
[    1.180000] task: c7440000 ti: c743a000 task.ti: c743a000
[    1.180000] PC is at memcmp+0x10/0x54
[    1.180000] LR is at gpmi_nand_probe+0x42c/0x894
[    1.180000] pc : [<c025fcb0>]    lr : [<c02f6a68>]    psr: 20000053
[    1.180000] sp : c743be2c  ip : 600000d3  fp : ffffffff
[    1.180000] r10: 000005d0  r9 : c02f5f08  r8 : 00000000
[    1.180000] r7 : c75858a8  r6 : c75858a8  r5 : c7585b18  r4 : c7585800
[    1.180000] r3 : 000005d0  r2 : 00000004  r1 : c05c33e4  r0 : 000005d0
[    1.180000] Flags: nzCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment kernel
[    1.180000] Control: 0005317f  Table: 40004000  DAC: 00000017
[    1.180000] Process swapper (pid: 1, stack limit = 0xc743a1c0)
--------------------------------------------------------------------

This patch rearrange the init procedure:
   Set the NAND_SKIP_BBTSCAN to skip the nand scan firstly, and after we
   set the proper settings, we will call the chip->scan_bbt() manually.

Cc: stable@vger.kernel.org # 3.12
Signed-off-by: Huang Shijie <b32955@freescale.com>
Reported-by: Fabio Estevam <festevam@gmail.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-12 10:17:57 -08:00
Linus Torvalds
10d0c9705e DeviceTree updates for 3.13. This is a bit larger pull request than
usual for this cycle with lots of clean-up.
 
 - Cross arch clean-up and consolidation of early DT scanning code.
 - Clean-up and removal of arch prom.h headers. Makes arch specific
   prom.h optional on all but Sparc.
 - Addition of interrupts-extended property for devices connected to
   multiple interrupt controllers.
 - Refactoring of DT interrupt parsing code in preparation for deferred
   probe of interrupts.
 - ARM cpu and cpu topology bindings documentation.
 - Various DT vendor binding documentation updates.
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Merge tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull devicetree updates from Rob Herring:
 "DeviceTree updates for 3.13.  This is a bit larger pull request than
  usual for this cycle with lots of clean-up.

   - Cross arch clean-up and consolidation of early DT scanning code.
   - Clean-up and removal of arch prom.h headers.  Makes arch specific
     prom.h optional on all but Sparc.
   - Addition of interrupts-extended property for devices connected to
     multiple interrupt controllers.
   - Refactoring of DT interrupt parsing code in preparation for
     deferred probe of interrupts.
   - ARM cpu and cpu topology bindings documentation.
   - Various DT vendor binding documentation updates"

* tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (82 commits)
  powerpc: add missing explicit OF includes for ppc
  dt/irq: add empty of_irq_count for !OF_IRQ
  dt: disable self-tests for !OF_IRQ
  of: irq: Fix interrupt-map entry matching
  MIPS: Netlogic: replace early_init_devtree() call
  of: Add Panasonic Corporation vendor prefix
  of: Add Chunghwa Picture Tubes Ltd. vendor prefix
  of: Add AU Optronics Corporation vendor prefix
  of/irq: Fix potential buffer overflow
  of/irq: Fix bug in interrupt parsing refactor.
  of: set dma_mask to point to coherent_dma_mask
  of: add vendor prefix for PHYTEC Messtechnik GmbH
  DT: sort vendor-prefixes.txt
  of: Add vendor prefix for Cadence
  of: Add empty for_each_available_child_of_node() macro definition
  arm/versatile: Fix versatile irq specifications.
  of/irq: create interrupts-extended property
  microblaze/pci: Drop PowerPC-ism from irq parsing
  of/irq: Create of_irq_parse_and_map_pci() to consolidate arch code.
  of/irq: Use irq_of_parse_and_map()
  ...
2013-11-12 16:52:17 +09:00
Huang Shijie
7b3d2fb920 mtd: gpmi: fix kernel BUG due to racing DMA operations
[1] The gpmi uses the nand_command_lp to issue the commands to NAND chips.
    The gpmi issues a DMA operation with gpmi_cmd_ctrl when it handles
    a NAND_CMD_NONE control command. So when we read a page(NAND_CMD_READ0)
    from the NAND, we may send two DMA operations back-to-back.

    If we do not serialize the two DMA operations, we will meet a bug when

    1.1) we enable CONFIG_DMA_API_DEBUG, CONFIG_DMADEVICES_DEBUG,
         and CONFIG_DEBUG_SG.

    1.2) Use the following commands in an UART console and a SSH console:
         cmd 1: while true;do dd if=/dev/mtd0 of=/dev/null;done
         cmd 1: while true;do dd if=/dev/mmcblk0 of=/dev/null;done

    The kernel log shows below:
    -----------------------------------------------------------------
    kernel BUG at lib/scatterlist.c:28!
    Unable to handle kernel NULL pointer dereference at virtual address 00000000
      .........................
    [<80044a0c>] (__bug+0x18/0x24) from [<80249b74>] (sg_next+0x48/0x4c)
    [<80249b74>] (sg_next+0x48/0x4c) from [<80255398>] (debug_dma_unmap_sg+0x170/0x1a4)
    [<80255398>] (debug_dma_unmap_sg+0x170/0x1a4) from [<8004af58>] (dma_unmap_sg+0x14/0x6c)
    [<8004af58>] (dma_unmap_sg+0x14/0x6c) from [<8027e594>] (mxs_dma_tasklet+0x18/0x1c)
    [<8027e594>] (mxs_dma_tasklet+0x18/0x1c) from [<8007d444>] (tasklet_action+0x114/0x164)
    -----------------------------------------------------------------

    1.3) Assume the two DMA operations is X (first) and Y (second).

         The root cause of the bug:
	   Assume process P issues DMA X, and sleep on the completion
	 @this->dma_done. X's tasklet callback is dma_irq_callback. It firstly
	 wake up the process sleeping on the completion @this->dma_done,
	 and then trid to unmap the scatterlist S. The waked process P will
	 issue Y in another ARM core. Y initializes S->sg_magic to zero
	 with sg_init_one(), while dma_irq_callback is unmapping S at the same
	 time.

	 See the diagram:

                   ARM core 0              |         ARM core 1
	 -------------------------------------------------------------
         (P issues DMA X, then sleep)  --> |
                                           |
         (X's tasklet wakes P)         --> |
                                           |
                                           | <-- (P begin to issue DMA Y)
                                           |
         (X's tasklet unmap the            |
      scatterlist S with dma_unmap_sg) --> | <-- (Y calls sg_init_one() to init
                                           |      scatterlist S)
                                           |

[2] This patch serialize both the X and Y in the following way:
     Unmap the DMA scatterlist S firstly, and wake up the process at the end
     of the DMA callback, in such a way, Y will be executed after X.

     After this patch:

                   ARM core 0              |         ARM core 1
	 -------------------------------------------------------------
         (P issues DMA X, then sleep)  --> |
                                           |
         (X's tasklet unmap the            |
      scatterlist S with dma_unmap_sg) --> |
                                           |
         (X's tasklet wakes P)         --> |
                                           |
                                           | <-- (P begin to issue DMA Y)
                                           |
                                           | <-- (Y calls sg_init_one() to init
                                           |     scatterlist S)
                                           |

Cc: stable@vger.kernel.org # 3.2
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-11 11:44:36 -08:00