of: Add KUnit test to confirm DTB is loaded

Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
root node, and that the of_have_populated_dt() API works properly. We
skip the test when CONFIG_OF_EARLY_FLATREE=n because in that case we
know architecture code hasn't called unflatten_(and_copy_)?device_tree()
which would populate some sort of root node.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Reviewed-by: David Gow <davidgow@google.com>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20240217010557.2381548-8-sboyd@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

of: Create of_root if no dtb provided by firmware

When enabling CONFIG_OF on a platform where 'of_root' is not populated
by firmware, we end up without a root node. In order to apply overlays
and create subnodes of the root node, we need one. Create this root node
by unflattening an empty builtin dtb.

If firmware provides a flattened device tree (FDT) then the FDT is
unflattened via setup_arch(). Otherwise, the call to
unflatten(_and_copy)?_device_tree() will create an empty root node.

We make of_have_populated_dt() return true only if the DTB was loaded by
firmware so that existing callers don't change behavior after this
patch. The call in the of platform code is removed because it prevents
overlays from creating platform devices when the empty root node is
used.

[sboyd@kernel.org: Update of_have_populated_dt() to treat this empty dtb
as not populated. Drop setup_of() initcall]

Signed-off-by: Frank Rowand <frowand.list@gmail.com>
Link: https://lore.kernel.org/r/20230317053415.2254616-2-frowand.list@gmail.com
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20240217010557.2381548-3-sboyd@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

of: Move CPU node related functions to their own file

drivers/of/base.c is quite long and we've accumulated a number of CPU
node functions. Let's move them to a new file, cpu.c, along with the
lone of_cpu_device_node_get() in of_device.h. Moving the declaration has
no effect yet as of.h is included by of_device.h. This serves as
preparation to disentangle the includes in of_device.h and
of_platform.h.

Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20230329-dt-cpu-header-cleanups-v1-4-581e2605fe47@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

of: Move of_modalias() to module.c

Create a specific .c file for OF related module handling.
Move of_modalias() inside as a first step.

The helper is exposed through of.h even though it is only used by core
files because the users from device.c will soon be split into an OF-only
helper in module.c as well as a device-oriented inline helper in
of_device.h. Putting this helper in of_private.h would require to
include of_private.h from of_device.h, which is not acceptable.

Suggested-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230404172148.82422-10-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

of: net: move of_net under net/

Rob suggests to move of_net.c from under drivers/of/ somewhere
to the networking code.

Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

of: Add a common kexec FDT setup function

Both arm64 and powerpc do essentially the same FDT /chosen setup for
kexec. The differences are either omissions that arm64 should have
or additional properties that will be ignored. The setup code can be
combined and shared by both powerpc and arm64.

The differences relative to the arm64 version:
- If /chosen doesn't exist, it will be created (should never happen).
- Any old dtb and initrd reserved memory will be released.
- The new initrd and elfcorehdr are marked reserved.
- "linux,booted-from-kexec" is set.

The differences relative to the powerpc version:
- "kaslr-seed" and "rng-seed" may be set.
- "linux,elfcorehdr" is set.
- Any existing "linux,usable-memory-range" is removed.

Combine the code for setting up the /chosen node in the FDT and updating
the memory reservation for kexec, for powerpc and arm64, in
of_kexec_alloc_and_setup_fdt() and move it to "drivers/of/kexec.c".

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210221174930.27324-6-nramas@linux.microsoft.com

net: phy: Move of_mdio from drivers/of to drivers/net/mdio

Better place for of_mdio.c is drivers/net/mdio.
Move of_mdio.c from drivers/of to drivers/net/mdio

Signed-off-by: Calvin Johnson <calvin.johnson@oss.nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

PCI: Move OF-related PCI functions into PCI core

Following what has been done for other subsystems, move the remaining PCI
related code out of drivers/of/ and into drivers/pci/of.c

With this, we can kill a few kconfig symbols.

Signed-off-by: Rob Herring <robh@kernel.org>
[bhelgaas: minor whitespace, comment cleanups]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Frank Rowand <frowand.list@gmail.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

of: make kobject and bin_attribute support configurable

Having device_nodes be kobjects is only needed if sysfs or OF_DYNAMIC is
enabled. Otherwise, having a kobject in struct device_node is
unnecessary bloat in minimal kernel configurations.

Likewise, bin_attribute is only needed in struct property when sysfs is
enabled, so we can make it configurable too.

Tested-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Frank Rowand <frowand.list@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Rob Herring <robh@kernel.org>

of: Move OF property and graph API from base.c to property.c

base.c contains both core OF functions and increasingly other
functionality such as accessing properties and graphs, including
convenience functions. In the near future this would also include OF
specific implementation of the fwnode property and graph APIs.

Create driver/of/property.c to contain procedures for accessing and
interpreting device tree properties. The procedures are moved from
drivers/of/base.c, with no changes other than copying only the includes
required by the moved procedures.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rob Herring <robh@kernel.org>

mtd: nand: move of_get_nand_xxx() helpers into nand_base.c

Now that all drivers go through nand_set_flash_node() to parse the generic
NAND properties, we can move all of_get_nand_xxx() helpers in to
nand_base.c, make them static and remove of_mtd.c and of_mtd.h.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

of, numa: Add NUMA of binding implementation.

Add device tree parsing for NUMA topology using device
"numa-node-id" property in distance-map and cpu nodes.

This is a complete rewrite of a previous patch by:
Ganapatrao Kulkarni<gkulkarni@caviumnetworks.com>

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

of: clean-up unnecessary libfdt include paths

With the libfdt include fixups to use "" instead of <> in the
latest dtc import in commit 4760597 (scripts/dtc: Update to upstream
version 9d3649bd3be245c9), it is no longer necessary to add explicit
include paths to use libfdt. Remove these across the kernel.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: linux-mips@linux-mips.org
Cc: linuxppc-dev@lists.ozlabs.org

dt: OF_UNITTEST make dependency broken

If CONFIG_OF_UNITTEST=y then a kernel image make will always cause .version to
be incremented, even if there are not source changes. This is caused by
a lack of dependency tracking and checking for
drivers/of/unittest-data/testcases.dtb.o.

Signed-off-by: Frank Rowand <frank.rowand@sonymobile.com>
Signed-off-by: Rob Herring <robh@kernel.org>

of/overlay: Introduce DT overlay support

Overlays are a method to dynamically modify part of the kernel's
device tree with dynamically loaded data. Add the core functionality to
parse, apply and remove an overlay changeset. The core functionality
takes care of managing the overlay data format and performing the add
and remove. Drivers are expected to use the overlay functionality to
support custom expansion busses commonly found on consumer development
boards like the BeagleBone or Raspberry Pi.

The overlay code uses CONFIG_OF_DYNAMIC changesets to perform the low
level work of modifying the devicetree.

Documentation about internal and APIs is provided in
Documentation/devicetree/overlay-notes.txt

v2:
- Switch from __of_node_alloc() to __of_node_dup()
- Documentation fixups
- Remove 2-pass processing of properties
- Remove separate ov_lock; just use the DT mutex.
v1:
- Drop delete capability using '-' prefix. The '-' prefixed names
are valid properties and nodes and there is no need for it just yet.
- Do not update special properties - name & phandle ones.
- Change order of node attachment, so that the special property update
works.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

of/unittest: Rename selftest.c to unittest.c

This is unit testing code. It should use that name because it makes more
sense than 'selftest'. Rename the files to match and rename the config
variable.

Signed-off-by: Grant Likely <grant.likely@linaro.org>

of: Introduce Device Tree resolve support.

Introduce support for dynamic device tree resolution.
Using it, it is possible to prepare a device tree that's
been loaded on runtime to be modified and inserted at the kernel
live tree.

Export of of_resolve and bug fix of double free by
Guenter Roeck <groeck@juniper.net>

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Don't need to select CONFIG_OF_DYNAMIC and CONFIG_OF_DEVICE]
[grant.likely: Don't need to depend on OF or !SPARC]
[grant.likely: Factor out duplicate code blocks into single function]
Signed-off-by: Grant Likely <grant.likely@linaro.org>

Adding selftest testdata dynamically into live tree

This patch attaches selftest's device tree data (required by /drivers/of/selftest.c)
dynamically into live device tree. First, it links selftest device tree data into the
kernel image and then iterates over all the nodes and attaches them into the live tree.
Once the testcases are complete, it removes the data attached.

This patch will remove the manual process of addition and removal of selftest device
tree data into the machine's dts file.

Tested successfully with current selftest's testcases.

Signed-off-by: Gaurav Minocha <gaurav.minocha.os@gmail.com>
[glikely: Removed ability to build as a module and fixed no-devicetree bug]
Signed-off-by: Grant Likely <grant.likely@linaro.org>

of: Move CONFIG_OF_DYNAMIC code into a separate file

Split the dynamic device tree code into a separate file to make it
really clear what features CONFIF_OF_DYNAMIC add to the kernel. Without
CONFIG_OF_DYNAMIC only properties can be changed, and notifiers do not
get sent. Enabling it turns on reference counting, notifiers and the
ability to add and remove nodes.

v2: Moved of_node_release() into dynamic.c

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Rob Herring <robh+dt@kernel.org>

of/fdt: add FDT address translation support

Copy u-boot's FDT address translation code from common/fdt_support. This
code was originally based on the kernel's unflattened DT address parsing
code.

This commit can be reverted once relicensing of this code to GPLv2/BSD
is done and it is added to libfdt.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Grant Likely <grant.likely@linaro.org>

of/fdt: Convert FDT functions to use libfdt

The kernel FDT functions predate libfdt and are much more limited in
functionality. Also, the kernel functions and libfdt functions are
not compatible with each other because they have different definitions
of node offsets. To avoid this incompatibility and in preparation to
add more FDT parsing functions which will need libfdt, let's first
convert the existing code to use libfdt.

The FDT unflattening, top-level FDT scanning, and property retrieval
functions are converted to use libfdt. The scanning code should be
re-worked to be more efficient and understandable by using libfdt to
find nodes directly by path or compatible strings.

Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>

drivers: of: add initialization code for dynamic reserved memory

This patch adds support for dynamically allocated reserved memory regions
declared in device tree. Such regions are defined by 'size', 'alignment'
and 'alloc-ranges' properties.

Based on previous code provided by Josh Cartwright <joshc@codeaurora.org>

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

Revert "drivers: of: add initialization code for dma reserved memory"

This reverts commit 9d8eab7af79cb4ce2de5de39f82c455b1f796963. There is
still no consensus on the bindings for the reserved memory and various
drawbacks of the proposed solution has been shown, so the best now is to
revert it completely and start again from scratch later.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

drivers: of: add initialization code for dma reserved memory

This patch adds device tree support for contiguous and reserved memory
regions defined in device tree.

Large memory blocks can be reliably reserved only during early boot.
This must happen before the whole memory management subsystem is
initialized, because we need to ensure that the given contiguous blocks
are not yet allocated by kernel. Also it must happen before kernel
mappings for the whole low memory are created, to ensure that there will
be no mappings (for reserved blocks) or mapping with special properties
can be created (for CMA blocks). This all happens before device tree
structures are unflattened, so we need to get reserved memory layout
directly from fdt.

Later, those reserved memory regions are assigned to devices on each
device structure initialization.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>

i2c: move OF helpers into the core

I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

of: remove CONFIG_OF_DEVICE

CONFIG_OF_DEVICE is always selected when CONFIG_OF is enabled, so remove
it and simplify of_platform.h and of_device.h headers. This also fixes
!OF compiles using of_platform_populate.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

dmaengine: move drivers/of/dma.c -> drivers/dma/of-dma.c

as requested by Rob

Suggested-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

of: Add generic device tree DMA helpers

This is based upon the work by Benoit Cousson [1] and Nicolas Ferre [2]
to add some basic helpers to retrieve a DMA controller device_node and the
DMA request/channel information.

Aim of DMA helpers
- The purpose of device-tree is to describe the capabilites of the hardware.
Thinking about DMA controllers purely from the context of the hardware to
begin with, we can describe a device in terms of a DMA controller as
follows ...
1. Number of DMA controllers
2. Number of channels (maybe physical or logical)
3. Mapping of DMA requests signals to DMA controller
4. Number of DMA interrupts
5. Mapping of DMA interrupts to channels
- With the above in mind the aim of the DT DMA helper functions is to extract
the above information from the DT and provide to the appropriate driver.
However, due to the vast number of DMA controllers and not all are using a
common driver (such as DMA Engine) it has been seen that this is not a
trivial task. In previous discussions on this topic the following concerns
have been raised ...
1. How does the binding support devices with multiple DMA controllers?
2. How to support both legacy DMA controllers not using DMA Engine as
well as those that support DMA Engine.
3. When using with DMA Engine how do we support the various
implementations where the opaque filter function parameter differs
between implementations?
4. How do we handle DMA channels that are identified with a string
versus a integer?
- Hence the design of the DMA helpers has to accomodate the above or align on
an agreement what can be or should be supported.

Design of DMA helpers

1. Registering DMA controllers

In the case of DMA controllers that are using DMA Engine, requesting a
channel is performed by calling the following function.

struct dma_chan *dma_request_channel(dma_cap_mask_t mask,
dma_filter_fn filter_fn,
void *filter_param);

The mask variable is used to match a type of the device controller in a list
of controllers. The filter_fn and filter_param are used to identify the
required dma channel and return a handle to the dma channel of type dma_chan.

From the examples I have seen, the mask and filter_fn are constant
for a given DMA controller and therefore, we can specify these as controller
specific data when registering the DMA controller with the device-tree DMA
helpers.

The filter_param variable is of an unknown type and is typically specific
to the DMA engine implementation for a given DMA controller. To allow some
flexibility in the type and formating of this filter_param we employ an
xlate to translate the device-tree binding information into the appropriate
format. The xlate function used for a DMA controller can also be specified
when registering the DMA controller with the device-tree DMA helpers.

Based upon the above, a function for registering the DMA controller with the
DMA helpers now looks like the below. The data variable is used to pass a
pointer to DMA controller specific data used by the xlate function.

int of_dma_controller_register(struct device_node *np,
struct dma_chan *(*of_dma_xlate)
(struct of_phandle_args *, struct of_dma *),
void *data)

For example, in the case where DMA engine is used, we define the following
structure (that stores the DMA engine capability mask and filter function)
and pass this to the data variable in the above function.

struct of_dma_filter_info {
dma_cap_mask_t dma_cap;
dma_filter_fn filter_fn;
};

2. Representing and requesting channel information

Please see the dma binding documentation included in this patch for a
description of how DMA controllers and client information should be
represented with device-tree. For more information on how this binding
came about please see [3]. In addition to this, feedback received from
the Linux kernel summit showed a consensus (among those who attended) to
use a name to identify DMA client information [4].

A DMA channel can be requested by calling the following function, where name
is a required parameter used for identifying a DMA channel. This function
has been designed to return a structure of type dma_chan to work with the
DMA engine driver. Note that if DMA engine is used then drivers should be
using the DMA engine API dma_request_slave_channel() (implemented in part 2
of this series, "dmaengine: add helper function to request a slave DMA
channel") which will in turn call the below function if device-tree is
present. The aim being to have a common DMA engine interface regardless of
whether device tree is being used.

struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
char *name)

3. Supporting legacy devices not using DMA Engine

These devices present a problem, as there may not be a uniform way to easily
support them with regard to device tree. Ideally, these should be migrated
to DMA engine. However, if this is not possible, then they should still be
able to use this binding, the only constaint imposed by this implementation
is that when requesting a DMA channel via of_dma_request_slave_channel(), it
will return a type of dma_chan.

This implementation has been tested on OMAP4430 using the kernel v3.6-rc5. I
have validated that MMC is working on the PANDA board with this implementation.
My development branch for testing on OMAP can be found here [5].

v6: - minor corrections in DMA binding documentation
v5: - minor update to binding documentation
- added loop to exhaustively search for a slave channel in the case where
there could be alternative channels available
v4: - revert the removal of xlate function from v3
- update the proposed binding format and APIs based upon discussions [3]
v3: - avoid passing an xlate function and instead pass DMA engine parameters
- define number of dma channels and requests in dma-controller node
v2: - remove of_dma_to_resource API
- make property #dma-cells required (no fallback anymore)
- another check in of_dma_xlate_onenumbercell() function

[1] http://article.gmane.org/gmane.linux.drivers.devicetree/12022
[2] http://article.gmane.org/gmane.linux.ports.arm.omap/73622
[3] http://marc.info/?l=linux-omap&m=133582085008539&w=2
[4] http://pad.linaro.org/arm-mini-summit-2012
[5] https://github.com/jonhunter/linux/tree/dev-dt-dma

Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Reviewed-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>

spi/devicetree: Move devicetree support code into spi directory

The SPI device tree support code isn't shared by any other subsystem. It can
be moved into the core drivers/spi directory and the exported symbol can be
removed.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>

gpio: Move DT support code into drivers/gpio

The code in drivers/of/gpio.c isn't shared by any other subsystem since it
is all gpiolib specific. drivers/gpio is a better place to maintain these
functions.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>

of/mtd/nand: add generic bindings and helpers

- nand-ecc-mode : String, operation mode of the NAND ecc mode.
Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
"soft_bch".
- nand-bus-width : 8 or 16 bus width if not present 8
- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Stefan Roese <sr@denx.de>

of: Add device tree selftests

Add some runtime test cases for the library of device tree parsing functions.

v2: - Add testcase for phandle with 0 args
- Don't run testcases if testcase data isn't present in device tree

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

pci/of: Match PCI devices to OF nodes dynamically

powerpc has two different ways of matching PCI devices to their
corresponding OF node (if any) for historical reasons. The ppc64 one
does a scan looking for matching bus/dev/fn, while the ppc32 one does a
scan looking only for matching dev/fn on each level in order to be
agnostic to busses being renumbered (which Linux does on some
platforms).

This removes both and instead moves the matching code to the PCI core
itself. It's the most logical place to do it: when a pci_dev is created,
we know the parent and thus can do a single level scan for the matching
device_node (if any).

The benefit is that all archs now get the matching for free. There's one
hook the arch might want to provide to match a PHB bus to its device
node. A default weak implementation is provided that looks for the
parent device device node, but it's not entirely reliable on powerpc for
various reasons so powerpc provides its own.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Michal Simek <monstr@monstr.eu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>

of/pci: move of_irq_map_pci() into generic code

There is a tiny difference between PPC32 and PPC64. Microblaze uses the
PPC32 variant.

Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
[grant.likely@secretlab.ca: Added comment to #endif, moved documentation
block to function implementation, fixed for non ppc and microblaze
compiles]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

of/net: Move of_get_mac_address() to a common source file.

There are two identical implementations of of_get_mac_address(), one
each in arch/powerpc/kernel/prom_parse.c and
arch/microblaze/kernel/prom_parse.c. Move this function to a new
common file of_net.{c,h} and adjust all the callers to include the new
header.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
[grant.likely@secretlab.ca: protect header with #ifdef]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

of/promtree: make drivers/of/pdt.c no longer sparc-only

Clean up pdt.c:
- make build dependent upon config OF_PROMTREE
- #ifdef out the sparc-specific stuff
- create pdt-specific header

Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

of/address: merge of_iomap()

Merge common code between Microblaze and PowerPC. This patch creates
new of_address.h and address.c files to containing address translation
and mapping routines. First routine to be moved it of_iomap()

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Michal Simek <monstr@monstr.eu>
CC: Stephen Rothwell <sfr@canb.auug.org.au>

of/irq: Move irq_of_parse_and_map() to common code

Merge common code between PowerPC and Microblaze. SPARC implements
irq_of_parse_and_map(), but the implementation is different, so it
does not use this code.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>

of/flattree: merge find_flat_dt_string and initial_boot_params

Merge common code between Microblaze and PowerPC.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>

openfirmware: Add OF phylib support code

Add support for parsing the device tree for PHY devices on an MDIO bus.
Currently many of the PowerPC ethernet drivers are open coding a solution
for reading data out of the device tree to find the correct PHY device.
This patch implements a set of common routines to:

a) let MDIO bus drivers register phy_devices described in the tree, and
b) let MAC drivers find the correct phy_device via the tree.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

spi: Add OF binding support for SPI busses

This patch adds support for populating an SPI bus based on data in the
OF device tree. This is useful for powerpc platforms which use the
device tree instead of discrete code for describing platform layout.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

[POWERPC] i2c: Fix build breakage introduced by OF helpers

Fix build breakage introduced in commit "[POWERPC] i2c: OF helpers for
the i2c API". If i2c-core is compiled as a module, the helper needs
to be compiled as a module, as well. Rename i2c.c to of_i2c.c to
avoid name space conflict.

[paulus@samba.org: Changed dependency from OF to PPC_OF to avoid
sparc{32,64} allmodconfig breakage.]

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] i2c: OF helpers for the i2c API

This implements various helpers to support OF bindings for the i2c
API.

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] OF helpers for the GPIO API

This implements various helpers to support OF bindings for the GPIO
LIB API.

Previously this was PowerPC specific, but it seems this code isn't
arch-dependent anyhow, so let's place it into of/.

SPARC will not see this addition yet, real hardware seem to not use
GPIOs at all. But this might change:

http://www.leox.org/docs/faq_MLleon.html

"16-bit I/O port" sounds promising. :-)

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Paul Mackerras <paulus@samba.org>

Create drivers/of/platform.c

and populate it with the common parts from PowerPC and Sparc[64].

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>

Begin to consolidate of_device.c

This moves all the common parts for the Sparc, Sparc64 and PowerPC
of_device.c files into drivers/of/device.c.

Apart from the simple move, Sparc gains of_match_node() and a call to
of_node_put in of_release_dev(). PowerPC gains better recovery if
device_create_file() fails in of_device_register().

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>

Start split out of common open firmware code

This creates drivers/of/base.c (depending on CONFIG_OF) and puts
the first trivially common bits from the prom.c files into it.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>