1 files changed, 0 insertions, 1447 deletions
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
deleted file mode 100644
index 7400d7555dc3..000000000000
--- a/Documentation/powerpc/booting-without-of.txt
+++ /dev/null
@@ -1,1447 +0,0 @@
-           Booting the Linux/ppc kernel without Open Firmware
-           --------------------------------------------------
-(c) 2005 Benjamin Herrenschmidt <benh at kernel.crashing.org>,
-    IBM Corp.
-(c) 2005 Becky Bruce <becky.bruce at freescale.com>,
-    Freescale Semiconductor, FSL SOC and 32-bit additions
-(c) 2006 MontaVista Software, Inc.
-    Flash chip node definition
-Table of Contents
-=================
-  I - Introduction
-    1) Entry point for arch/powerpc
-    2) Board support
-  II - The DT block format
-    1) Header
-    2) Device tree generalities
-    3) Device tree "structure" block
-    4) Device tree "strings" block
-  III - Required content of the device tree
-    1) Note about cells and address representation
-    2) Note about "compatible" properties
-    3) Note about "name" properties
-    4) Note about node and property names and character set
-    5) Required nodes and properties
-      a) The root node
-      b) The /cpus node
-      c) The /cpus/* nodes
-      d) the /memory node(s)
-      e) The /chosen node
-      f) the /soc<SOCname> node
-  IV - "dtc", the device tree compiler
-  V - Recommendations for a bootloader
-  VI - System-on-a-chip devices and nodes
-    1) Defining child nodes of an SOC
-    2) Representing devices without a current OF specification
-      a) PHY nodes
-      b) Interrupt controllers
-      c) 4xx/Axon EMAC ethernet nodes
-      d) Xilinx IP cores
-      e) USB EHCI controllers
-      f) MDIO on GPIOs
-      g) SPI busses
-  VII - Specifying interrupt information for devices
-    1) interrupts property
-    2) interrupt-parent property
-    3) OpenPIC Interrupt Controllers
-    4) ISA Interrupt Controllers
-  VIII - Specifying device power management information (sleep property)
-  Appendix A - Sample SOC node for MPC8540
-Revision Information
-====================
-   May 18, 2005: Rev 0.1 - Initial draft, no chapter III yet.
-   May 19, 2005: Rev 0.2 - Add chapter III and bits & pieces here or
-                           clarifies the fact that a lot of things are
-                           optional, the kernel only requires a very
-                           small device tree, though it is encouraged
-                           to provide an as complete one as possible.
-   May 24, 2005: Rev 0.3 - Precise that DT block has to be in RAM
-                         - Misc fixes
-                         - Define version 3 and new format version 16
-                           for the DT block (version 16 needs kernel
-                           patches, will be fwd separately).
-                           String block now has a size, and full path
-                           is replaced by unit name for more
-                           compactness.
-                           linux,phandle is made optional, only nodes
-                           that are referenced by other nodes need it.
-                           "name" property is now automatically
-                           deduced from the unit name
-   June 1, 2005: Rev 0.4 - Correct confusion between OF_DT_END and
-                           OF_DT_END_NODE in structure definition.
-                         - Change version 16 format to always align
-                           property data to 4 bytes. Since tokens are
-                           already aligned, that means no specific
-                           required alignment between property size
-                           and property data. The old style variable
-                           alignment would make it impossible to do
-                           "simple" insertion of properties using
-                           memmove (thanks Milton for
-                           noticing). Updated kernel patch as well
-                         - Correct a few more alignment constraints
-                         - Add a chapter about the device-tree
-                           compiler and the textural representation of
-                           the tree that can be "compiled" by dtc.
-   November 21, 2005: Rev 0.5
-                         - Additions/generalizations for 32-bit
-                         - Changed to reflect the new arch/powerpc
-                           structure
-                         - Added chapter VI
- ToDo:
-        - Add some definitions of interrupt tree (simple/complex)
-        - Add some definitions for PCI host bridges
-        - Add some common address format examples
-        - Add definitions for standard properties and "compatible"
-          names for cells that are not already defined by the existing
-          OF spec.
-        - Compare FSL SOC use of PCI to standard and make sure no new
-          node definition required.
-        - Add more information about node definitions for SOC devices
-          that currently have no standard, like the FSL CPM.
-I - Introduction
-================
-During the recent development of the Linux/ppc64 kernel, and more
-specifically, the addition of new platform types outside of the old
-IBM pSeries/iSeries pair, it was decided to enforce some strict rules
-regarding the kernel entry and bootloader <-> kernel interfaces, in
-order to avoid the degeneration that had become the ppc32 kernel entry
-point and the way a new platform should be added to the kernel. The
-legacy iSeries platform breaks those rules as it predates this scheme,
-but no new board support will be accepted in the main tree that
-doesn't follow them properly.  In addition, since the advent of the
-arch/powerpc merged architecture for ppc32 and ppc64, new 32-bit
-platforms and 32-bit platforms which move into arch/powerpc will be
-required to use these rules as well.
-The main requirement that will be defined in more detail below is
-the presence of a device-tree whose format is defined after Open
-Firmware specification. However, in order to make life easier
-to embedded board vendors, the kernel doesn't require the device-tree
-to represent every device in the system and only requires some nodes
-and properties to be present. This will be described in detail in
-section III, but, for example, the kernel does not require you to
-create a node for every PCI device in the system. It is a requirement
-to have a node for PCI host bridges in order to provide interrupt
-routing informations and memory/IO ranges, among others. It is also
-recommended to define nodes for on chip devices and other busses that
-don't specifically fit in an existing OF specification. This creates a
-great flexibility in the way the kernel can then probe those and match
-drivers to device, without having to hard code all sorts of tables. It
-also makes it more flexible for board vendors to do minor hardware
-upgrades without significantly impacting the kernel code or cluttering
-it with special cases.
-1) Entry point for arch/powerpc
-------------------------------
-   There is one and one single entry point to the kernel, at the start
-   of the kernel image. That entry point supports two calling
-   conventions:
-        a) Boot from Open Firmware. If your firmware is compatible
-        with Open Firmware (IEEE 1275) or provides an OF compatible
-        client interface API (support for "interpret" callback of
-        forth words isn't required), you can enter the kernel with:
-              r5 : OF callback pointer as defined by IEEE 1275
-              bindings to powerpc. Only the 32-bit client interface
-              is currently supported
-              r3, r4 : address & length of an initrd if any or 0
-              The MMU is either on or off; the kernel will run the
-              trampoline located in arch/powerpc/kernel/prom_init.c to
-              extract the device-tree and other information from open
-              firmware and build a flattened device-tree as described
-              in b). prom_init() will then re-enter the kernel using
-              the second method. This trampoline code runs in the
-              context of the firmware, which is supposed to handle all
-              exceptions during that time.
-        b) Direct entry with a flattened device-tree block. This entry
-        point is called by a) after the OF trampoline and can also be
-        called directly by a bootloader that does not support the Open
-        Firmware client interface. It is also used by "kexec" to
-        implement "hot" booting of a new kernel from a previous
-        running one. This method is what I will describe in more
-        details in this document, as method a) is simply standard Open
-        Firmware, and thus should be implemented according to the
-        various standard documents defining it and its binding to the
-        PowerPC platform. The entry point definition then becomes:
-                r3 : physical pointer to the device-tree block
-                (defined in chapter II) in RAM
-                r4 : physical pointer to the kernel itself. This is
-                used by the assembly code to properly disable the MMU
-                in case you are entering the kernel with MMU enabled
-                and a non-1:1 mapping.
-                r5 : NULL (as to differentiate with method a)
-        Note about SMP entry: Either your firmware puts your other
-        CPUs in some sleep loop or spin loop in ROM where you can get
-        them out via a soft reset or some other means, in which case
-        you don't need to care, or you'll have to enter the kernel
-        with all CPUs. The way to do that with method b) will be
-        described in a later revision of this document.
-2) Board support
----------------
-64-bit kernels:
-   Board supports (platforms) are not exclusive config options. An
-   arbitrary set of board supports can be built in a single kernel
-   image. The kernel will "know" what set of functions to use for a
-   given platform based on the content of the device-tree. Thus, you
-   should:
-        a) add your platform support as a _boolean_ option in
-        arch/powerpc/Kconfig, following the example of PPC_PSERIES,
-        PPC_PMAC and PPC_MAPLE. The later is probably a good
-        example of a board support to start from.
-        b) create your main platform file as
-        "arch/powerpc/platforms/myplatform/myboard_setup.c" and add it
-        to the Makefile under the condition of your CONFIG_
-        option. This file will define a structure of type "ppc_md"
-        containing the various callbacks that the generic code will
-        use to get to your platform specific code
-        c) Add a reference to your "ppc_md" structure in the
-        "machines" table in arch/powerpc/kernel/setup_64.c if you are
-        a 64-bit platform.
-        d) request and get assigned a platform number (see PLATFORM_*
-        constants in arch/powerpc/include/asm/processor.h
-32-bit embedded kernels:
-  Currently, board support is essentially an exclusive config option.
-  The kernel is configured for a single platform.  Part of the reason
-  for this is to keep kernels on embedded systems small and efficient;
-  part of this is due to the fact the code is already that way. In the
-  future, a kernel may support multiple platforms, but only if the
-  platforms feature the same core architecture.  A single kernel build
-  cannot support both configurations with Book E and configurations
-  with classic Powerpc architectures.
-  32-bit embedded platforms that are moved into arch/powerpc using a
-  flattened device tree should adopt the merged tree practice of
-  setting ppc_md up dynamically, even though the kernel is currently
-  built with support for only a single platform at a time.  This allows
-  unification of the setup code, and will make it easier to go to a
-  multiple-platform-support model in the future.
-NOTE: I believe the above will be true once Ben's done with the merge
-of the boot sequences.... someone speak up if this is wrong!
-  To add a 32-bit embedded platform support, follow the instructions
-  for 64-bit platforms above, with the exception that the Kconfig
-  option should be set up such that the kernel builds exclusively for
-  the platform selected.  The processor type for the platform should
-  enable another config option to select the specific board
-  supported.
-NOTE: If Ben doesn't merge the setup files, may need to change this to
-point to setup_32.c
-   I will describe later the boot process and various callbacks that
-   your platform should implement.
-II - The DT block format
-========================
-This chapter defines the actual format of the flattened device-tree
-passed to the kernel. The actual content of it and kernel requirements
-are described later. You can find example of code manipulating that
-format in various places, including arch/powerpc/kernel/prom_init.c
-which will generate a flattened device-tree from the Open Firmware
-representation, or the fs2dt utility which is part of the kexec tools
-which will generate one from a filesystem representation. It is
-expected that a bootloader like uboot provides a bit more support,
-that will be discussed later as well.
-Note: The block has to be in main memory. It has to be accessible in
-both real mode and virtual mode with no mapping other than main
-memory. If you are writing a simple flash bootloader, it should copy
-the block to RAM before passing it to the kernel.
-1) Header
---------
-   The kernel is entered with r3 pointing to an area of memory that is
-   roughly described in arch/powerpc/include/asm/prom.h by the structure
-   boot_param_header:
-struct boot_param_header {
-        u32     magic;                  /* magic word OF_DT_HEADER */
-        u32     totalsize;              /* total size of DT block */
-        u32     off_dt_struct;          /* offset to structure */
-        u32     off_dt_strings;         /* offset to strings */
-        u32     off_mem_rsvmap;         /* offset to memory reserve map
-                                           */
-        u32     version;                /* format version */
-        u32     last_comp_version;      /* last compatible version */
-        /* version 2 fields below */
-        u32     boot_cpuid_phys;        /* Which physical CPU id we're
-                                           booting on */
-        /* version 3 fields below */
-        u32     size_dt_strings;        /* size of the strings block */
-        /* version 17 fields below */
-        u32     size_dt_struct;         /* size of the DT structure block */
-};
-   Along with the constants:
-/* Definitions used by the flattened device tree */
-#define OF_DT_HEADER            0xd00dfeed      /* 4: version,
-                                                   4: total size */
-#define OF_DT_BEGIN_NODE        0x1             /* Start node: full name
-                                                   */
-#define OF_DT_END_NODE          0x2             /* End node */
-#define OF_DT_PROP              0x3             /* Property: name off,
-                                                   size, content */
-#define OF_DT_END               0x9
-   All values in this header are in big endian format, the various
-   fields in this header are defined more precisely below. All
-   "offset" values are in bytes from the start of the header; that is
-   from the value of r3.
-   - magic
-     This is a magic value that "marks" the beginning of the
-     device-tree block header. It contains the value 0xd00dfeed and is
-     defined by the constant OF_DT_HEADER
-   - totalsize
-     This is the total size of the DT block including the header. The
-     "DT" block should enclose all data structures defined in this
-     chapter (who are pointed to by offsets in this header). That is,
-     the device-tree structure, strings, and the memory reserve map.
-   - off_dt_struct
-     This is an offset from the beginning of the header to the start
-     of the "structure" part the device tree. (see 2) device tree)
-   - off_dt_strings
-     This is an offset from the beginning of the header to the start
-     of the "strings" part of the device-tree
-   - off_mem_rsvmap
-     This is an offset from the beginning of the header to the start
-     of the reserved memory map. This map is a list of pairs of 64-
-     bit integers. Each pair is a physical address and a size. The
-     list is terminated by an entry of size 0. This map provides the
-     kernel with a list of physical memory areas that are "reserved"
-     and thus not to be used for memory allocations, especially during
-     early initialization. The kernel needs to allocate memory during
-     boot for things like un-flattening the device-tree, allocating an
-     MMU hash table, etc... Those allocations must be done in such a
-     way to avoid overriding critical things like, on Open Firmware
-     capable machines, the RTAS instance, or on some pSeries, the TCE
-     tables used for the iommu. Typically, the reserve map should
-     contain _at least_ this DT block itself (header,total_size). If
-     you are passing an initrd to the kernel, you should reserve it as
-     well. You do not need to reserve the kernel image itself. The map
-     should be 64-bit aligned.
-   - version
-     This is the version of this structure. Version 1 stops
-     here. Version 2 adds an additional field boot_cpuid_phys.
-     Version 3 adds the size of the strings block, allowing the kernel
-     to reallocate it easily at boot and free up the unused flattened
-     structure after expansion. Version 16 introduces a new more
-     "compact" format for the tree itself that is however not backward
-     compatible. Version 17 adds an additional field, size_dt_struct,
-     allowing it to be reallocated or moved more easily (this is
-     particularly useful for bootloaders which need to make
-     adjustments to a device tree based on probed information). You
-     should always generate a structure of the highest version defined
-     at the time of your implementation. Currently that is version 17,
-     unless you explicitly aim at being backward compatible.
-   - last_comp_version
-     Last compatible version. This indicates down to what version of
-     the DT block you are backward compatible. For example, version 2
-     is backward compatible with version 1 (that is, a kernel build
-     for version 1 will be able to boot with a version 2 format). You
-     should put a 1 in this field if you generate a device tree of
-     version 1 to 3, or 16 if you generate a tree of version 16 or 17
-     using the new unit name format.
-   - boot_cpuid_phys
-     This field only exist on version 2 headers. It indicate which
-     physical CPU ID is calling the kernel entry point. This is used,
-     among others, by kexec. If you are on an SMP system, this value
-     should match the content of the "reg" property of the CPU node in
-     the device-tree corresponding to the CPU calling the kernel entry
-     point (see further chapters for more informations on the required
-     device-tree contents)
-   - size_dt_strings
-     This field only exists on version 3 and later headers.  It
-     gives the size of the "strings" section of the device tree (which
-     starts at the offset given by off_dt_strings).
-   - size_dt_struct
-     This field only exists on version 17 and later headers.  It gives
-     the size of the "structure" section of the device tree (which
-     starts at the offset given by off_dt_struct).
-   So the typical layout of a DT block (though the various parts don't
-   need to be in that order) looks like this (addresses go from top to
-   bottom):
-             ------------------------------
-       r3 -> |  struct boot_param_header  |
-             ------------------------------
-             |      (alignment gap) (*)   |
-             ------------------------------
-             |      memory reserve map    |
-             ------------------------------
-             |      (alignment gap)       |
-             ------------------------------
-             |                            |
-             |    device-tree structure   |
-             |                            |
-             ------------------------------
-             |      (alignment gap)       |
-             ------------------------------
-             |                            |
-             |     device-tree strings    |
-             |                            |
-      -----> ------------------------------
-      |
-      |
-      --- (r3 + totalsize)
-  (*) The alignment gaps are not necessarily present; their presence
-      and size are dependent on the various alignment requirements of
-      the individual data blocks.
-2) Device tree generalities
---------------------------
-This device-tree itself is separated in two different blocks, a
-structure block and a strings block. Both need to be aligned to a 4
-byte boundary.
-First, let's quickly describe the device-tree concept before detailing
-the storage format. This chapter does _not_ describe the detail of the
-required types of nodes & properties for the kernel, this is done
-later in chapter III.
-The device-tree layout is strongly inherited from the definition of
-the Open Firmware IEEE 1275 device-tree. It's basically a tree of
-nodes, each node having two or more named properties. A property can
-have a value or not.
-It is a tree, so each node has one and only one parent except for the
-root node who has no parent.
-A node has 2 names. The actual node name is generally contained in a
-property of type "name" in the node property list whose value is a
-zero terminated string and is mandatory for version 1 to 3 of the
-format definition (as it is in Open Firmware). Version 16 makes it
-optional as it can generate it from the unit name defined below.
-There is also a "unit name" that is used to differentiate nodes with
-the same name at the same level, it is usually made of the node
-names, the "@" sign, and a "unit address", which definition is
-specific to the bus type the node sits on.
-The unit name doesn't exist as a property per-se but is included in
-the device-tree structure. It is typically used to represent "path" in
-the device-tree. More details about the actual format of these will be
-below.
-The kernel powerpc generic code does not make any formal use of the
-unit address (though some board support code may do) so the only real
-requirement here for the unit address is to ensure uniqueness of
-the node unit name at a given level of the tree. Nodes with no notion
-of address and no possible sibling of the same name (like /memory or
-/cpus) may omit the unit address in the context of this specification,
-or use the "@0" default unit address. The unit name is used to define
-a node "full path", which is the concatenation of all parent node
-unit names separated with "/".
-The root node doesn't have a defined name, and isn't required to have
-a name property either if you are using version 3 or earlier of the
-format. It also has no unit address (no @ symbol followed by a unit
-address). The root node unit name is thus an empty string. The full
-path to the root node is "/".
-Every node which actually represents an actual device (that is, a node
-which isn't only a virtual "container" for more nodes, like "/cpus"
-is) is also required to have a "device_type" property indicating the
-type of node .
-Finally, every node that can be referenced from a property in another
-node is required to have a "linux,phandle" property. Real open
-firmware implementations provide a unique "phandle" value for every
-node that the "prom_init()" trampoline code turns into
-"linux,phandle" properties. However, this is made optional if the
-flattened device tree is used directly. An example of a node
-referencing another node via "phandle" is when laying out the
-interrupt tree which will be described in a further version of this
-document.
-This "linux, phandle" property is a 32-bit value that uniquely
-identifies a node. You are free to use whatever values or system of
-values, internal pointers, or whatever to generate these, the only
-requirement is that every node for which you provide that property has
-a unique value for it.
-Here is an example of a simple device-tree. In this example, an "o"
-designates a node followed by the node unit name. Properties are
-presented with their name followed by their content. "content"
-represents an ASCII string (zero terminated) value, while <content>
-represents a 32-bit hexadecimal value. The various nodes in this
-example will be discussed in a later chapter. At this point, it is
-only meant to give you a idea of what a device-tree looks like. I have
-purposefully kept the "name" and "linux,phandle" properties which
-aren't necessary in order to give you a better idea of what the tree
-looks like in practice.
-  / o device-tree
-      |- name = "device-tree"
-      |- model = "MyBoardName"
-      |- compatible = "MyBoardFamilyName"
-      |- #address-cells = <2>
-      |- #size-cells = <2>
-      |- linux,phandle = <0>
-      |
-      o cpus
-      | | - name = "cpus"
-      | | - linux,phandle = <1>
-      | | - #address-cells = <1>
-      | | - #size-cells = <0>
-      | |
-      | o PowerPC,970@0
-      |   |- name = "PowerPC,970"
-      |   |- device_type = "cpu"
-      |   |- reg = <0>
-      |   |- clock-frequency = <5f5e1000>
-      |   |- 64-bit
-      |   |- linux,phandle = <2>
-      |
-      o memory@0
-      | |- name = "memory"
-      | |- device_type = "memory"
-      | |- reg = <00000000 00000000 00000000 20000000>
-      | |- linux,phandle = <3>
-      |
-      o chosen
-        |- name = "chosen"
-        |- bootargs = "root=/dev/sda2"
-        |- linux,phandle = <4>
-This tree is almost a minimal tree. It pretty much contains the
-minimal set of required nodes and properties to boot a linux kernel;
-that is, some basic model informations at the root, the CPUs, and the
-physical memory layout.  It also includes misc information passed
-through /chosen, like in this example, the platform type (mandatory)
-and the kernel command line arguments (optional).
-The /cpus/PowerPC,970@0/64-bit property is an example of a
-property without a value. All other properties have a value. The
-significance of the #address-cells and #size-cells properties will be
-explained in chapter IV which defines precisely the required nodes and
-properties and their content.
-3) Device tree "structure" block
-The structure of the device tree is a linearized tree structure. The
-"OF_DT_BEGIN_NODE" token starts a new node, and the "OF_DT_END_NODE"
-ends that node definition. Child nodes are simply defined before
-"OF_DT_END_NODE" (that is nodes within the node). A 'token' is a 32
-bit value. The tree has to be "finished" with a OF_DT_END token
-Here's the basic structure of a single node:
-     * token OF_DT_BEGIN_NODE (that is 0x00000001)
-     * for version 1 to 3, this is the node full path as a zero
-       terminated string, starting with "/". For version 16 and later,
-       this is the node unit name only (or an empty string for the
-       root node)
-     * [align gap to next 4 bytes boundary]
-     * for each property:
-        * token OF_DT_PROP (that is 0x00000003)
-        * 32-bit value of property value size in bytes (or 0 if no
-          value)
-        * 32-bit value of offset in string block of property name
-        * property value data if any
-        * [align gap to next 4 bytes boundary]
-     * [child nodes if any]
-     * token OF_DT_END_NODE (that is 0x00000002)
-So the node content can be summarized as a start token, a full path,
-a list of properties, a list of child nodes, and an end token. Every
-child node is a full node structure itself as defined above.
-NOTE: The above definition requires that all property definitions for
-a particular node MUST precede any subnode definitions for that node.
-Although the structure would not be ambiguous if properties and
-subnodes were intermingled, the kernel parser requires that the
-properties come first (up until at least 2.6.22).  Any tools
-manipulating a flattened tree must take care to preserve this
-constraint.
-4) Device tree "strings" block
-In order to save space, property names, which are generally redundant,
-are stored separately in the "strings" block. This block is simply the
-whole bunch of zero terminated strings for all property names
-concatenated together. The device-tree property definitions in the
-structure block will contain offset values from the beginning of the
-strings block.
-III - Required content of the device tree
-=========================================
-WARNING: All "linux,*" properties defined in this document apply only
-to a flattened device-tree. If your platform uses a real
-implementation of Open Firmware or an implementation compatible with
-the Open Firmware client interface, those properties will be created
-by the trampoline code in the kernel's prom_init() file. For example,
-that's where you'll have to add code to detect your board model and
-set the platform number. However, when using the flattened device-tree
-entry point, there is no prom_init() pass, and thus you have to
-provide those properties yourself.
-1) Note about cells and address representation
----------------------------------------------
-The general rule is documented in the various Open Firmware
-documentations. If you choose to describe a bus with the device-tree
-and there exist an OF bus binding, then you should follow the
-specification. However, the kernel does not require every single
-device or bus to be described by the device tree.
-In general, the format of an address for a device is defined by the
-parent bus type, based on the #address-cells and #size-cells
-properties.  Note that the parent's parent definitions of #address-cells
-and #size-cells are not inherited so every node with children must specify
-them.  The kernel requires the root node to have those properties defining
-addresses format for devices directly mapped on the processor bus.
-Those 2 properties define 'cells' for representing an address and a
-size. A "cell" is a 32-bit number. For example, if both contain 2
-like the example tree given above, then an address and a size are both
-composed of 2 cells, and each is a 64-bit number (cells are
-concatenated and expected to be in big endian format). Another example
-is the way Apple firmware defines them, with 2 cells for an address
-and one cell for a size.  Most 32-bit implementations should define
-#address-cells and #size-cells to 1, which represents a 32-bit value.
-Some 32-bit processors allow for physical addresses greater than 32
-bits; these processors should define #address-cells as 2.
-"reg" properties are always a tuple of the type "address size" where
-the number of cells of address and size is specified by the bus
-#address-cells and #size-cells. When a bus supports various address
-spaces and other flags relative to a given address allocation (like
-prefetchable, etc...) those flags are usually added to the top level
-bits of the physical address. For example, a PCI physical address is
-made of 3 cells, the bottom two containing the actual address itself
-while the top cell contains address space indication, flags, and pci
-bus & device numbers.
-For busses that support dynamic allocation, it's the accepted practice
-to then not provide the address in "reg" (keep it 0) though while
-providing a flag indicating the address is dynamically allocated, and
-then, to provide a separate "assigned-addresses" property that
-contains the fully allocated addresses. See the PCI OF bindings for
-details.
-In general, a simple bus with no address space bits and no dynamic
-allocation is preferred if it reflects your hardware, as the existing
-kernel address parsing functions will work out of the box. If you
-define a bus type with a more complex address format, including things
-like address space bits, you'll have to add a bus translator to the
-prom_parse.c file of the recent kernels for your bus type.
-The "reg" property only defines addresses and sizes (if #size-cells is
-non-0) within a given bus. In order to translate addresses upward
-(that is into parent bus addresses, and possibly into CPU physical
-addresses), all busses must contain a "ranges" property. If the
-"ranges" property is missing at a given level, it's assumed that
-translation isn't possible, i.e., the registers are not visible on the
-parent bus.  The format of the "ranges" property for a bus is a list
-of:
-        bus address, parent bus address, size
-"bus address" is in the format of the bus this bus node is defining,
-that is, for a PCI bridge, it would be a PCI address. Thus, (bus
-address, size) defines a range of addresses for child devices. "parent
-bus address" is in the format of the parent bus of this bus. For
-example, for a PCI host controller, that would be a CPU address. For a
-PCI<->ISA bridge, that would be a PCI address. It defines the base
-address in the parent bus where the beginning of that range is mapped.
-For a new 64-bit powerpc board, I recommend either the 2/2 format or
-Apple's 2/1 format which is slightly more compact since sizes usually
-fit in a single 32-bit word.   New 32-bit powerpc boards should use a
-1/1 format, unless the processor supports physical addresses greater
-than 32-bits, in which case a 2/1 format is recommended.
-Alternatively, the "ranges" property may be empty, indicating that the
-registers are visible on the parent bus using an identity mapping
-translation.  In other words, the parent bus address space is the same
-as the child bus address space.
-2) Note about "compatible" properties
-------------------------------------
-These properties are optional, but recommended in devices and the root
-node. The format of a "compatible" property is a list of concatenated
-zero terminated strings. They allow a device to express its
-compatibility with a family of similar devices, in some cases,
-allowing a single driver to match against several devices regardless
-of their actual names.
-3) Note about "name" properties
-------------------------------
-While earlier users of Open Firmware like OldWorld macintoshes tended
-to use the actual device name for the "name" property, it's nowadays
-considered a good practice to use a name that is closer to the device
-class (often equal to device_type). For example, nowadays, ethernet
-controllers are named "ethernet", an additional "model" property
-defining precisely the chip type/model, and "compatible" property
-defining the family in case a single driver can driver more than one
-of these chips. However, the kernel doesn't generally put any
-restriction on the "name" property; it is simply considered good
-practice to follow the standard and its evolutions as closely as
-possible.
-Note also that the new format version 16 makes the "name" property
-optional. If it's absent for a node, then the node's unit name is then
-used to reconstruct the name. That is, the part of the unit name
-before the "@" sign is used (or the entire unit name if no "@" sign
-is present).
-4) Note about node and property names and character set
-------------------------------------------------------
-While open firmware provides more flexible usage of 8859-1, this
-specification enforces more strict rules. Nodes and properties should
-be comprised only of ASCII characters 'a' to 'z', '0' to
-'9', ',', '.', '_', '+', '#', '?', and '-'. Node names additionally
-allow uppercase characters 'A' to 'Z' (property names should be
-lowercase. The fact that vendors like Apple don't respect this rule is
-irrelevant here). Additionally, node and property names should always
-begin with a character in the range 'a' to 'z' (or 'A' to 'Z' for node
-names).
-The maximum number of characters for both nodes and property names
-is 31. In the case of node names, this is only the leftmost part of
-a unit name (the pure "name" property), it doesn't include the unit
-address which can extend beyond that limit.
-5) Required nodes and properties
--------------------------------
-  These are all that are currently required. However, it is strongly
-  recommended that you expose PCI host bridges as documented in the
-  PCI binding to open firmware, and your interrupt tree as documented
-  in OF interrupt tree specification.
-  a) The root node
-  The root node requires some properties to be present:
-    - model : this is your board name/model
-    - #address-cells : address representation for "root" devices
-    - #size-cells: the size representation for "root" devices
-    - device_type : This property shouldn't be necessary. However, if
-      you decide to create a device_type for your root node, make sure it
-      is _not_ "chrp" unless your platform is a pSeries or PAPR compliant
-      one for 64-bit, or a CHRP-type machine for 32-bit as this will
-      matched by the kernel this way.
-  Additionally, some recommended properties are:
-    - compatible : the board "family" generally finds its way here,
-      for example, if you have 2 board models with a similar layout,
-      that typically get driven by the same platform code in the
-      kernel, you would use a different "model" property but put a
-      value in "compatible". The kernel doesn't directly use that
-      value but it is generally useful.
-  The root node is also generally where you add additional properties
-  specific to your board like the serial number if any, that sort of
-  thing. It is recommended that if you add any "custom" property whose
-  name may clash with standard defined ones, you prefix them with your
-  vendor name and a comma.
-  b) The /cpus node
-  This node is the parent of all individual CPU nodes. It doesn't
-  have any specific requirements, though it's generally good practice
-  to have at least:
-               #address-cells = <00000001>
-               #size-cells    = <00000000>
-  This defines that the "address" for a CPU is a single cell, and has
-  no meaningful size. This is not necessary but the kernel will assume
-  that format when reading the "reg" properties of a CPU node, see
-  below
-  c) The /cpus/* nodes
-  So under /cpus, you are supposed to create a node for every CPU on
-  the machine. There is no specific restriction on the name of the
-  CPU, though It's common practice to call it PowerPC,<name>. For
-  example, Apple uses PowerPC,G5 while IBM uses PowerPC,970FX.
-  Required properties:
-    - device_type : has to be "cpu"
-    - reg : This is the physical CPU number, it's a single 32-bit cell
-      and is also used as-is as the unit number for constructing the
-      unit name in the full path. For example, with 2 CPUs, you would
-      have the full path:
-        /cpus/PowerPC,970FX@0
-        /cpus/PowerPC,970FX@1
-      (unit addresses do not require leading zeroes)
-    - d-cache-block-size : one cell, L1 data cache block size in bytes (*)
-    - i-cache-block-size : one cell, L1 instruction cache block size in
-      bytes
-    - d-cache-size : one cell, size of L1 data cache in bytes
-    - i-cache-size : one cell, size of L1 instruction cache in bytes
-(*) The cache "block" size is the size on which the cache management
-instructions operate. Historically, this document used the cache
-"line" size here which is incorrect. The kernel will prefer the cache
-block size and will fallback to cache line size for backward
-compatibility.
-  Recommended properties:
-    - timebase-frequency : a cell indicating the frequency of the
-      timebase in Hz. This is not directly used by the generic code,
-      but you are welcome to copy/paste the pSeries code for setting
-      the kernel timebase/decrementer calibration based on this
-      value.
-    - clock-frequency : a cell indicating the CPU core clock frequency
-      in Hz. A new property will be defined for 64-bit values, but if
-      your frequency is < 4Ghz, one cell is enough. Here as well as
-      for the above, the common code doesn't use that property, but
-      you are welcome to re-use the pSeries or Maple one. A future
-      kernel version might provide a common function for this.
-    - d-cache-line-size : one cell, L1 data cache line size in bytes
-      if different from the block size
-    - i-cache-line-size : one cell, L1 instruction cache line size in
-      bytes if different from the block size
-  You are welcome to add any property you find relevant to your board,
-  like some information about the mechanism used to soft-reset the
-  CPUs. For example, Apple puts the GPIO number for CPU soft reset
-  lines in there as a "soft-reset" property since they start secondary
-  CPUs by soft-resetting them.
-  d) the /memory node(s)
-  To define the physical memory layout of your board, you should
-  create one or more memory node(s). You can either create a single
-  node with all memory ranges in its reg property, or you can create
-  several nodes, as you wish. The unit address (@ part) used for the
-  full path is the address of the first range of memory defined by a
-  given node. If you use a single memory node, this will typically be
-  @0.
-  Required properties:
-    - device_type : has to be "memory"
-    - reg : This property contains all the physical memory ranges of
-      your board. It's a list of addresses/sizes concatenated
-      together, with the number of cells of each defined by the
-      #address-cells and #size-cells of the root node. For example,
-      with both of these properties being 2 like in the example given
-      earlier, a 970 based machine with 6Gb of RAM could typically
-      have a "reg" property here that looks like:
-      00000000 00000000 00000000 80000000
-      00000001 00000000 00000001 00000000
-      That is a range starting at 0 of 0x80000000 bytes and a range
-      starting at 0x100000000 and of 0x100000000 bytes. You can see
-      that there is no memory covering the IO hole between 2Gb and
-      4Gb. Some vendors prefer splitting those ranges into smaller
-      segments, but the kernel doesn't care.
-  e) The /chosen node
-  This node is a bit "special". Normally, that's where open firmware
-  puts some variable environment information, like the arguments, or
-  the default input/output devices.
-  This specification makes a few of these mandatory, but also defines
-  some linux-specific properties that would be normally constructed by
-  the prom_init() trampoline when booting with an OF client interface,
-  but that you have to provide yourself when using the flattened format.
-  Recommended properties:
-    - bootargs : This zero-terminated string is passed as the kernel
-      command line
-    - linux,stdout-path : This is the full path to your standard
-      console device if any. Typically, if you have serial devices on
-      your board, you may want to put the full path to the one set as
-      the default console in the firmware here, for the kernel to pick
-      it up as its own default console. If you look at the function
-      set_preferred_console() in arch/ppc64/kernel/setup.c, you'll see
-      that the kernel tries to find out the default console and has
-      knowledge of various types like 8250 serial ports. You may want
-      to extend this function to add your own.
-  Note that u-boot creates and fills in the chosen node for platforms
-  that use it.
-  (Note: a practice that is now obsolete was to include a property
-  under /chosen called interrupt-controller which had a phandle value
-  that pointed to the main interrupt controller)
-  f) the /soc<SOCname> node
-  This node is used to represent a system-on-a-chip (SOC) and must be
-  present if the processor is a SOC. The top-level soc node contains
-  information that is global to all devices on the SOC. The node name
-  should contain a unit address for the SOC, which is the base address
-  of the memory-mapped register set for the SOC. The name of an soc
-  node should start with "soc", and the remainder of the name should
-  represent the part number for the soc.  For example, the MPC8540's
-  soc node would be called "soc8540".
-  Required properties:
-    - device_type : Should be "soc"
-    - ranges : Should be defined as specified in 1) to describe the
-      translation of SOC addresses for memory mapped SOC registers.
-    - bus-frequency: Contains the bus frequency for the SOC node.
-      Typically, the value of this field is filled in by the boot
-      loader.
-  Recommended properties:
-    - reg : This property defines the address and size of the
-      memory-mapped registers that are used for the SOC node itself.
-      It does not include the child device registers - these will be
-      defined inside each child node.  The address specified in the
-      "reg" property should match the unit address of the SOC node.
-    - #address-cells : Address representation for "soc" devices.  The
-      format of this field may vary depending on whether or not the
-      device registers are memory mapped.  For memory mapped
-      registers, this field represents the number of cells needed to
-      represent the address of the registers.  For SOCs that do not
-      use MMIO, a special address format should be defined that
-      contains enough cells to represent the required information.
-      See 1) above for more details on defining #address-cells.
-    - #size-cells : Size representation for "soc" devices
-    - #interrupt-cells : Defines the width of cells used to represent
-       interrupts.  Typically this value is <2>, which includes a
-       32-bit number that represents the interrupt number, and a
-       32-bit number that represents the interrupt sense and level.
-       This field is only needed if the SOC contains an interrupt
-       controller.
-  The SOC node may contain child nodes for each SOC device that the
-  platform uses.  Nodes should not be created for devices which exist
-  on the SOC but are not used by a particular platform. See chapter VI
-  for more information on how to specify devices that are part of a SOC.
-  Example SOC node for the MPC8540:
-        soc8540@e0000000 {
-                #address-cells = <1>;
-                #size-cells = <1>;
-                #interrupt-cells = <2>;
-                device_type = "soc";
-                ranges = <00000000 e0000000 00100000>
-                reg = <e0000000 00003000>;
-                bus-frequency = <0>;
-        }
-IV - "dtc", the device tree compiler
-====================================
-dtc source code can be found at
-<http://git.jdl.com/gitweb/?p=dtc.git>
-WARNING: This version is still in early development stage; the
-resulting device-tree "blobs" have not yet been validated with the
-kernel. The current generated block lacks a useful reserve map (it will
-be fixed to generate an empty one, it's up to the bootloader to fill
-it up) among others. The error handling needs work, bugs are lurking,
-etc...
-dtc basically takes a device-tree in a given format and outputs a
-device-tree in another format. The currently supported formats are:
-  Input formats:
-  -------------
-     - "dtb": "blob" format, that is a flattened device-tree block
-       with
-        header all in a binary blob.
-     - "dts": "source" format. This is a text file containing a
-       "source" for a device-tree. The format is defined later in this
-        chapter.
-     - "fs" format. This is a representation equivalent to the
-        output of /proc/device-tree, that is nodes are directories and
-        properties are files
- Output formats:
- ---------------
-     - "dtb": "blob" format
-     - "dts": "source" format
-     - "asm": assembly language file. This is a file that can be
-       sourced by gas to generate a device-tree "blob". That file can
-       then simply be added to your Makefile. Additionally, the
-       assembly file exports some symbols that can be used.
-The syntax of the dtc tool is
-    dtc [-I <input-format>] [-O <output-format>]
-        [-o output-filename] [-V output_version] input_filename
-The "output_version" defines what version of the "blob" format will be
-generated. Supported versions are 1,2,3 and 16. The default is
-currently version 3 but that may change in the future to version 16.
-Additionally, dtc performs various sanity checks on the tree, like the
-uniqueness of linux, phandle properties, validity of strings, etc...
-The format of the .dts "source" file is "C" like, supports C and C++
-style comments.
-/ {
-}
-The above is the "device-tree" definition. It's the only statement
-supported currently at the toplevel.
-/ {
-  property1 = "string_value";   /* define a property containing a 0
-                                 * terminated string
-                                 */
-  property2 = <1234abcd>;       /* define a property containing a
-                                 * numerical 32-bit value (hexadecimal)
-                                 */
-  property3 = <12345678 12345678 deadbeef>;
-                                /* define a property containing 3
-                                 * numerical 32-bit values (cells) in
-                                 * hexadecimal
-                                 */
-  property4 = [0a 0b 0c 0d de ea ad be ef];
-                                /* define a property whose content is
-                                 * an arbitrary array of bytes
-                                 */
-  childnode@address {   /* define a child node named "childnode"
-                                 * whose unit name is "childnode at
-                                 * address"
-                                 */
-    childprop = "hello\n";      /* define a property "childprop" of
-                                 * childnode (in this case, a string)
-                                 */
-  };
-};
-Nodes can contain other nodes etc... thus defining the hierarchical
-structure of the tree.
-Strings support common escape sequences from C: "\n", "\t", "\r",
-"\(octal value)", "\x(hex value)".
-It is also suggested that you pipe your source file through cpp (gcc
-preprocessor) so you can use #include's, #define for constants, etc...
-Finally, various options are planned but not yet implemented, like
-automatic generation of phandles, labels (exported to the asm file so
-you can point to a property content and change it easily from whatever
-you link the device-tree with), label or path instead of numeric value
-in some cells to "point" to a node (replaced by a phandle at compile
-time), export of reserve map address to the asm file, ability to
-specify reserve map content at compile time, etc...
-We may provide a .h include file with common definitions of that
-proves useful for some properties (like building PCI properties or
-interrupt maps) though it may be better to add a notion of struct
-definitions to the compiler...
-V - Recommendations for a bootloader
-====================================
-Here are some various ideas/recommendations that have been proposed
-while all this has been defined and implemented.
-  - The bootloader may want to be able to use the device-tree itself
-    and may want to manipulate it (to add/edit some properties,
-    like physical memory size or kernel arguments). At this point, 2
-    choices can be made. Either the bootloader works directly on the
-    flattened format, or the bootloader has its own internal tree
-    representation with pointers (similar to the kernel one) and
-    re-flattens the tree when booting the kernel. The former is a bit
-    more difficult to edit/modify, the later requires probably a bit
-    more code to handle the tree structure. Note that the structure
-    format has been designed so it's relatively easy to "insert"
-    properties or nodes or delete them by just memmoving things
-    around. It contains no internal offsets or pointers for this
-    purpose.
-  - An example of code for iterating nodes & retrieving properties
-    directly from the flattened tree format can be found in the kernel
-    file arch/ppc64/kernel/prom.c, look at scan_flat_dt() function,
-    its usage in early_init_devtree(), and the corresponding various
-    early_init_dt_scan_*() callbacks. That code can be re-used in a
-    GPL bootloader, and as the author of that code, I would be happy
-    to discuss possible free licensing to any vendor who wishes to
-    integrate all or part of this code into a non-GPL bootloader.
-VI - System-on-a-chip devices and nodes
-=======================================
-Many companies are now starting to develop system-on-a-chip
-processors, where the processor core (CPU) and many peripheral devices
-exist on a single piece of silicon.  For these SOCs, an SOC node
-should be used that defines child nodes for the devices that make
-up the SOC. While platforms are not required to use this model in
-order to boot the kernel, it is highly encouraged that all SOC
-implementations define as complete a flat-device-tree as possible to
-describe the devices on the SOC.  This will allow for the
-genericization of much of the kernel code.
-1) Defining child nodes of an SOC
---------------------------------
-Each device that is part of an SOC may have its own node entry inside
-the SOC node.  For each device that is included in the SOC, the unit
-address property represents the address offset for this device's
-memory-mapped registers in the parent's address space.  The parent's
-address space is defined by the "ranges" property in the top-level soc
-node. The "reg" property for each node that exists directly under the
-SOC node should contain the address mapping from the child address space
-to the parent SOC address space and the size of the device's
-memory-mapped register file.
-For many devices that may exist inside an SOC, there are predefined
-specifications for the format of the device tree node.  All SOC child
-nodes should follow these specifications, except where noted in this
-document.
-See appendix A for an example partial SOC node definition for the
-MPC8540.
-2) Representing devices without a current OF specification
----------------------------------------------------------
-Currently, there are many devices on SOCs that do not have a standard
-representation pre-defined as part of the open firmware
-specifications, mainly because the boards that contain these SOCs are
-not currently booted using open firmware.   This section contains
-descriptions for the SOC devices for which new nodes have been
-defined; this list will expand as more and more SOC-containing
-platforms are moved over to use the flattened-device-tree model.
-VII - Specifying interrupt information for devices
-===================================================
-The device tree represents the busses and devices of a hardware
-system in a form similar to the physical bus topology of the
-hardware.
-In addition, a logical 'interrupt tree' exists which represents the
-hierarchy and routing of interrupts in the hardware.
-The interrupt tree model is fully described in the
-document "Open Firmware Recommended Practice: Interrupt
-Mapping Version 0.9".  The document is available at:
-<http://playground.sun.com/1275/practice>.
-1) interrupts property
----------------------
-Devices that generate interrupts to a single interrupt controller
-should use the conventional OF representation described in the
-OF interrupt mapping documentation.
-Each device which generates interrupts must have an 'interrupt'
-property.  The interrupt property value is an arbitrary number of
-of 'interrupt specifier' values which describe the interrupt or
-interrupts for the device.
-The encoding of an interrupt specifier is determined by the
-interrupt domain in which the device is located in the
-interrupt tree.  The root of an interrupt domain specifies in
-its #interrupt-cells property the number of 32-bit cells
-required to encode an interrupt specifier.  See the OF interrupt
-mapping documentation for a detailed description of domains.
-For example, the binding for the OpenPIC interrupt controller
-specifies  an #interrupt-cells value of 2 to encode the interrupt
-number and level/sense information. All interrupt children in an
-OpenPIC interrupt domain use 2 cells per interrupt in their interrupts
-property.
-The PCI bus binding specifies a #interrupt-cell value of 1 to encode
-which interrupt pin (INTA,INTB,INTC,INTD) is used.
-2) interrupt-parent property
----------------------------
-The interrupt-parent property is specified to define an explicit
-link between a device node and its interrupt parent in
-the interrupt tree.  The value of interrupt-parent is the
-phandle of the parent node.
-If the interrupt-parent property is not defined for a node, its
-interrupt parent is assumed to be an ancestor in the node's
-_device tree_ hierarchy.
-3) OpenPIC Interrupt Controllers
--------------------------------
-OpenPIC interrupt controllers require 2 cells to encode
-interrupt information.  The first cell defines the interrupt
-number.  The second cell defines the sense and level
-information.
-Sense and level information should be encoded as follows:
-        0 = low to high edge sensitive type enabled
-        1 = active low level sensitive type enabled
-        2 = active high level sensitive type enabled
-        3 = high to low edge sensitive type enabled
-4) ISA Interrupt Controllers
----------------------------
-ISA PIC interrupt controllers require 2 cells to encode
-interrupt information.  The first cell defines the interrupt
-number.  The second cell defines the sense and level
-information.
-ISA PIC interrupt controllers should adhere to the ISA PIC
-encodings listed below:
-        0 =  active low level sensitive type enabled
-        1 =  active high level sensitive type enabled
-        2 =  high to low edge sensitive type enabled
-        3 =  low to high edge sensitive type enabled
-VIII - Specifying Device Power Management Information (sleep property)
-===================================================================
-Devices on SOCs often have mechanisms for placing devices into low-power
-states that are decoupled from the devices' own register blocks.  Sometimes,
-this information is more complicated than a cell-index property can
-reasonably describe.  Thus, each device controlled in such a manner
-may contain a "sleep" property which describes these connections.
-The sleep property consists of one or more sleep resources, each of
-which consists of a phandle to a sleep controller, followed by a
-controller-specific sleep specifier of zero or more cells.
-The semantics of what type of low power modes are possible are defined
-by the sleep controller.  Some examples of the types of low power modes
-that may be supported are:
- - Dynamic: The device may be disabled or enabled at any time.
- - System Suspend: The device may request to be disabled or remain
-   awake during system suspend, but will not be disabled until then.
- - Permanent: The device is disabled permanently (until the next hard
-   reset).
-Some devices may share a clock domain with each other, such that they should
-only be suspended when none of the devices are in use.  Where reasonable,
-such nodes should be placed on a virtual bus, where the bus has the sleep
-property.  If the clock domain is shared among devices that cannot be
-reasonably grouped in this manner, then create a virtual sleep controller
-(similar to an interrupt nexus, except that defining a standardized
-sleep-map should wait until its necessity is demonstrated).
-Appendix A - Sample SOC node for MPC8540
-========================================
-        soc@e0000000 {
-                #address-cells = <1>;
-                #size-cells = <1>;
-                compatible = "fsl,mpc8540-ccsr", "simple-bus";
-                device_type = "soc";
-                ranges = <0x00000000 0xe0000000 0x00100000>
-                bus-frequency = <0>;
-                interrupt-parent = <&pic>;
-                ethernet@24000 {
-                        #address-cells = <1>;
-                        #size-cells = <1>;
-                        device_type = "network";
-                        model = "TSEC";
-                        compatible = "gianfar", "simple-bus";
-                        reg = <0x24000 0x1000>;
-                        local-mac-address = [ 00 E0 0C 00 73 00 ];
-                        interrupts = <29 2 30 2 34 2>;
-                        phy-handle = <&phy0>;
-                        sleep = <&pmc 00000080>;
-                        ranges;
-                        mdio@24520 {
-                                reg = <0x24520 0x20>;
-                                compatible = "fsl,gianfar-mdio";
-                                phy0: ethernet-phy@0 {
-                                        interrupts = <5 1>;
-                                        reg = <0>;
-                                        device_type = "ethernet-phy";
-                                };
-                                phy1: ethernet-phy@1 {
-                                        interrupts = <5 1>;
-                                        reg = <1>;
-                                        device_type = "ethernet-phy";
-                                };
-                                phy3: ethernet-phy@3 {
-                                        interrupts = <7 1>;
-                                        reg = <3>;
-                                        device_type = "ethernet-phy";
-                                };
-                        };
-                };
-                ethernet@25000 {
-                        device_type = "network";
-                        model = "TSEC";
-                        compatible = "gianfar";
-                        reg = <0x25000 0x1000>;
-                        local-mac-address = [ 00 E0 0C 00 73 01 ];
-                        interrupts = <13 2 14 2 18 2>;
-                        phy-handle = <&phy1>;
-                        sleep = <&pmc 00000040>;
-                };
-                ethernet@26000 {
-                        device_type = "network";
-                        model = "FEC";
-                        compatible = "gianfar";
-                        reg = <0x26000 0x1000>;
-                        local-mac-address = [ 00 E0 0C 00 73 02 ];
-                        interrupts = <41 2>;
-                        phy-handle = <&phy3>;
-                        sleep = <&pmc 00000020>;
-                };
-                serial@4500 {
-                        #address-cells = <1>;
-                        #size-cells = <1>;
-                        compatible = "fsl,mpc8540-duart", "simple-bus";
-                        sleep = <&pmc 00000002>;
-                        ranges;
-                        serial@4500 {
-                                device_type = "serial";
-                                compatible = "ns16550";
-                                reg = <0x4500 0x100>;
-                                clock-frequency = <0>;
-                                interrupts = <42 2>;
-                        };
-                        serial@4600 {
-                                device_type = "serial";
-                                compatible = "ns16550";
-                                reg = <0x4600 0x100>;
-                                clock-frequency = <0>;
-                                interrupts = <42 2>;
-                        };
-                };
-                pic: pic@40000 {
-                        interrupt-controller;
-                        #address-cells = <0>;
-                        #interrupt-cells = <2>;
-                        reg = <0x40000 0x40000>;
-                        compatible = "chrp,open-pic";
-                        device_type = "open-pic";
-                };
-                i2c@3000 {
-                        interrupts = <43 2>;
-                        reg = <0x3000 0x100>;
-                        compatible  = "fsl-i2c";
-                        dfsrr;
-                        sleep = <&pmc 00000004>;
-                };
-                pmc: power@e0070 {
-                        compatible = "fsl,mpc8540-pmc", "fsl,mpc8548-pmc";
-                        reg = <0xe0070 0x20>;
-                };
-        };