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+Flash partitions in device tree
+===============================
+
+Flash devices can be partitioned into one or more functional ranges (e.g. "boot
+code", "nvram", "kernel").
+
+Different devices may be partitioned in a different ways. Some may use a fixed
+flash layout set at production time. Some may use on-flash table that describes
+the geometry and naming/purpose of each functional region. It is also possible
+to see these methods mixed.
+
+To assist system software in locating partitions, we allow describing which
+method is used for a given flash device. To describe the method there should be
+a subnode of the flash device that is named 'partitions'. It must have a
+'compatible' property, which is used to identify the method to use.
+
+When a single partition is represented with a DT node (it depends on a used
+format) it may also be described using above rules ('compatible' and optionally
+some extra properties / subnodes). It allows describing more complex,
+hierarchical (multi-level) layouts and should be used if there is some
+significant relation between partitions or some partition internally uses
+another partitioning method.
+
+Available bindings are listed in the "partitions" subdirectory.
+
+
+Fixed Partitions
+================
+
+Partitions can be represented by sub-nodes of a flash device. This can be used
+on platforms which have strong conventions about which portions of a flash are
+used for what purposes, but which don't use an on-flash partition table such
+as RedBoot.
+
+The partition table should be a subnode of the flash node and should be named
+'partitions'. This node should have the following property:
+- compatible : (required) must be "fixed-partitions"
+Partitions are then defined in subnodes of the partitions node.
+
+For backwards compatibility partitions as direct subnodes of the flash device are
+supported. This use is discouraged.
+NOTE: also for backwards compatibility, direct subnodes that have a compatible
+string are not considered partitions, as they may be used for other bindings.
+
+#address-cells & #size-cells must both be present in the partitions subnode of the
+flash device. There are two valid values for both:
+<1>: for partitions that require a single 32-bit cell to represent their
+ size/address (aka the value is below 4 GiB)
+<2>: for partitions that require two 32-bit cells to represent their
+ size/address (aka the value is 4 GiB or greater).
+
+Required properties:
+- reg : The partition's offset and size within the flash
+
+Optional properties:
+- label : The label / name for this partition. If omitted, the label is taken
+ from the node name (excluding the unit address).
+- read-only : This parameter, if present, is a hint to Linux that this
+ partition should only be mounted read-only. This is usually used for flash
+ partitions containing early-boot firmware images or data which should not be
+ clobbered.
+- lock : Do not unlock the partition at initialization time (not supported on
+ all devices)
+- slc-mode: This parameter, if present, allows one to emulate SLC mode on a
+ partition attached to an MLC NAND thus making this partition immune to
+ paired-pages corruptions
+
+Examples:
+
+
+flash@0 {
+ partitions {
+ compatible = "fixed-partitions";
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ partition@0 {
+ label = "u-boot";
+ reg = <0x0000000 0x100000>;
+ read-only;
+ };
+
+ uimage@100000 {
+ reg = <0x0100000 0x200000>;
+ };
+ };
+};
+
+flash@1 {
+ partitions {
+ compatible = "fixed-partitions";
+ #address-cells = <1>;
+ #size-cells = <2>;
+
+ /* a 4 GiB partition */
+ partition@0 {
+ label = "filesystem";
+ reg = <0x00000000 0x1 0x00000000>;
+ };
+ };
+};
+
+flash@2 {
+ partitions {
+ compatible = "fixed-partitions";
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ /* an 8 GiB partition */
+ partition@0 {
+ label = "filesystem #1";
+ reg = <0x0 0x00000000 0x2 0x00000000>;
+ };
+
+ /* a 4 GiB partition */
+ partition@200000000 {
+ label = "filesystem #2";
+ reg = <0x2 0x00000000 0x1 0x00000000>;
+ };
+ };
+};
+
+flash@3 {
+ partitions {
+ compatible = "fixed-partitions";
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ partition@0 {
+ label = "bootloader";
+ reg = <0x000000 0x100000>;
+ read-only;
+ };
+
+ firmware@100000 {
+ label = "firmware";
+ reg = <0x100000 0xe00000>;
+ compatible = "brcm,trx";
+ };
+
+ calibration@f00000 {
+ label = "calibration";
+ reg = <0xf00000 0x100000>;
+ compatible = "fixed-partitions";
+ ranges = <0 0xf00000 0x100000>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ partition@0 {
+ label = "wifi0";
+ reg = <0x000000 0x080000>;
+ };
+
+ partition@80000 {
+ label = "wifi1";
+ reg = <0x080000 0x080000>;
+ };
+ };
+ };
+};