mtd: add datasheet's ECC information to nand_chip{}

1.) Why add the ECC information to the nand_chip{} ?
   Each nand chip has its requirement for the ECC correctability, such as
   "4bit ECC for each 512Byte" or "40bit ECC for each 1024Byte".
   This ECC info is very important to the nand controller, such as gpmi.

   Take the Micron MT29F64G08CBABA for example, its geometry is
   8KiB page size, 744 bytes oob size and it requires 40bit ECC per 1KiB.
   If we do not provide the ECC info to the gpmi nand driver, it has to
   calculate the ECC correctability itself. The gpmi driver will gets the 56bit
   ECC for per 1KiB which is beyond its BCH's 40bit ecc capibility.
   The gpmi will quits in this case. But in actually, the gpmi can supports
   this nand chip if it can get the right ECC info.

2.) about the new fields.
   The @ecc_strength_ds stands for the ecc bits needed within the @ecc_step_ds.
   The two fields should be set from the nand chip's datasheets.

   For example:
	"4bit ECC for each 512Byte" could be:
		@ecc_strength_ds = 4, @ecc_step_ds = 512.
	"40bit ECC for each 1024Byte" could be:
		@ecc_strength_ds = 40, @ecc_step_ds = 1024.

3.) Why do not re-use the @strength and @size in the nand_ecc_ctrl{}?
   The @strength and @size in nand_ecc_ctrl{} is used by the nand controller
   driver, while the @ecc_strength_ds and @ecc_step_ds are get from the datasheet.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Reviewed-and-tested-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: add data structures for Extended Parameter Page

Since the ONFI 2.1, the onfi spec adds the Extended Parameter Page
to store the ECC info.

The onfi spec tells us that if the nand chip's recommended ECC codeword
size is not 512 bytes, then the @ecc_bits is 0xff. The host _SHOULD_ then
read the Extended ECC information that is part of the extended parameter
page to retrieve the ECC requirements for this device.

This patch adds
    [1] the neccessary fields for nand_onfi_params{},
    [2] and adds the onfi_ext_ecc_info{} for Extended ECC information,
    [3] adds onfi_ext_section{} for extended sections,
    [4] and adds onfi_ext_param_page{} for the Extended Parameter Page.

Acked-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Huang Shijie <b32955@freescale.com>
Reviewed-and-tested-by: Brian Norris <computersforpeace@gmail.com>
[Brian: amended for checkpatch.pl]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: add a helper to get the supported features for ONFI nand

add a helper to get the supported features for ONFI nand.
Also add the neccessary macros.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Reviewed-and-tested-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: get the ECC info from the parameter page for ONFI nand

From the ONFI spec, we can just get the ECC info from the @ecc_bits field of
the parameter page.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Reviewed-and-tested-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: get the ECC info from the Extended Parameter Page

Since the ONFI 2.1, the onfi spec adds the Extended Parameter Page
to store the ECC info.

The onfi spec tells us that if the nand chip's recommended ECC codeword
size is not 512 bytes, then the @ecc_bits is 0xff. The host _SHOULD_ then
read the Extended ECC information that is part of the extended parameter
page to retrieve the ECC requirements for this device.

This patch implement the reading of the Extended Parameter Page, and parses
the sections for ECC type, and get the ECC info from the ECC section.

Tested this patch with Micron MT29F64G08CBABAWP.

Acked-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Huang Shijie <b32955@freescale.com>
Reviewed-and-tested-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: fix memory leak in ONFI extended parameter page

This fixes a memory leak in the ONFI support code for detecting the
required ECC levels from this commit:

  commit 6dcbe0cdd83fb5f77be4f44c9e06c535281c375a
  Author: Huang Shijie <b32955@freescale.com>
  Date:   Wed May 22 10:28:27 2013 +0800

      mtd: get the ECC info from the Extended Parameter Page

In the success case, we never freed the 'ep' buffer.

Also, this fixes an oversight in the same commit where we (harmlessly)
freed the NULL pointer.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
clk: mvebu: Add Core Divider clock

This commit introduces a new group of clocks present in Armada 370/XP
SoCs (called "Core Divider" clocks) and add a provider for them.
The only clock supported for now is the NAND clock (ndclk), but the
infrastructure to add the rest is already set.

Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
ARM: mvebu: Add a 2 GHz fixed-clock Armada 370/XP

Armada 370/XP SoCs have a 2 GHz fixed PLL that is used to feed
other clocks. This commit adds a DT representation of this clock
through a fixed-clock compatible node.

Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
ARM: mvebu: Add the core-divider clock to Armada 370/XP

The Armada 370/XP SoC has a clock provider called "Core Divider",
that is derived from a fixed 2 GHz PLL clock.

Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
ARM: mvebu: Add support for NAND controller in Armada 370/XP

The Armada 370 and Armada XP SoC have a NAND controller (aka NFCv2).
This commit adds support for it in Armada 370 and Armada XP SoC
common devicetree.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
ARM: mvebu: Enable NAND controller in Armada XP GP board

The Armada XP GP board has a NAND flash, so enable it in the devicetree.

In order to skip the driver's custom device detection and use only ONFI
detection, the "marvell,keep-config" parameter is used.
This is needed because we haven't support for setting the timings
parameters yet and must rely in bootloader's.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
mtd: nand: pxa3xx: Use devm_kzalloc

Replace regular kzalloc with managed devm_kzalloc
which simplifies the error path.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Use devm_ioremap_resource

Using the new devm_ioremap_resource() we can greatly
simplify resource handling.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Use devm_clk_get

Replacing clk_get by managed devm_clk_get, the error path
can be greatly simplified.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Use clk_prepare_enable and clk_disable_unprepare

This patch converts the module to use clk_prepare_enable and
clk_disable_unprepare variants as required by common clock framework.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Check for clk_prepare_enable() return value

clk_prepare_enable() can fail due to unknown reason.
Add a check for this and return the error code if it fails.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Move buffer release code to its own function

Create a function to release the buffer and the dma channel, thus undoing
what pxa3xx_nand_init_buff() did. This commit makes the code more readable
and will allow to handle non-DMA capable platforms easier.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Set info->use_dma properly

Currently, the variable info->use_dma is never set and always
zero-valued which means the driver never does DMA transfers.
We fix this by simply setting info->use_dma to the module parameter,
also named 'use_dma'. Note that the module parameter has the same name,
but different semantics.

This fixes a regression introduced by the below commit
which removed the info->use_dma variable set.

  commit 4eb2da8994042d68e84e31138788429a102da2ea
  Author: Lei Wen <leiwen@marvell.com>
  Date:   Mon Feb 28 10:32:13 2011 +0800

      mtd: pxa3xx_nand: unify prepare command

Before the above commit, the driver had use_dma=1 on all NAND commands
except on CMD_STATUS. This behavior is long lost and we are not
recovering in this patch, either.

This was spotted and verified by human inspection.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Nikita Kiryanov <nikita@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Reviewed-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Use of_machine_is_compatible()

This patch replaces cpu_is_pxa3xx() with of_machine_is_compatible()
which allows to build this driver for other platforms than ARCH_PXA.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Nikita Kiryanov <nikita@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Reviewed-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: nand: pxa3xx: Fix MODULE_DEVICE_TABLE declaration

This module's device table is incorrectly declared using
i2c_pxa_dt_ids, instead of pxa3xx_nand_dt_ids.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Nikita Kiryanov <nikita@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Reviewed-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>