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+CFI or JEDEC memory-mapped NOR flash, MTD-RAM (NVRAM...)
+
+Flash chips (Memory Technology Devices) are often used for solid state
+file systems on embedded devices.
+
+ - compatible : should contain the specific model of mtd chip(s)
+ used, if known, followed by either "cfi-flash", "jedec-flash",
+ "mtd-ram" or "mtd-rom".
+ - reg : Address range(s) of the mtd chip(s)
+ It's possible to (optionally) define multiple "reg" tuples so that
+ non-identical chips can be described in one node.
+ - bank-width : Width (in bytes) of the bank. Equal to the
+ device width times the number of interleaved chips.
+ - device-width : (optional) Width of a single mtd chip. If
+ omitted, assumed to be equal to 'bank-width'.
+ - #address-cells, #size-cells : Must be present if the device has
+ sub-nodes representing partitions (see below). In this case
+ both #address-cells and #size-cells must be equal to 1.
+ - no-unaligned-direct-access: boolean to disable the default direct
+ mapping of the flash.
+ On some platforms (e.g. MPC5200) a direct 1:1 mapping may cause
+ problems with JFFS2 usage, as the local bus (LPB) doesn't support
+ unaligned accesses as implemented in the JFFS2 code via memcpy().
+ By defining "no-unaligned-direct-access", the flash will not be
+ exposed directly to the MTD users (e.g. JFFS2) any more.
+ - linux,mtd-name: allow to specify the mtd name for retro capability with
+ physmap-flash drivers as boot loader pass the mtd partition via the old
+ device name physmap-flash.
+ - use-advanced-sector-protection: boolean to enable support for the
+ advanced sector protection (Spansion: PPB - Persistent Protection
+ Bits) locking.
+ - addr-gpios : (optional) List of GPIO descriptors that will be used to
+ address the MSBs address lines. The order goes from LSB to MSB.
+
+For JEDEC compatible devices, the following additional properties
+are defined:
+
+ - vendor-id : Contains the flash chip's vendor id (1 byte).
+ - device-id : Contains the flash chip's device id (1 byte).
+
+For ROM compatible devices (and ROM fallback from cfi-flash), the following
+additional (optional) property is defined:
+
+ - erase-size : The chip's physical erase block size in bytes.
+
+ The device tree may optionally contain endianness property.
+ little-endian or big-endian : It Represents the endianness that should be used
+ by the controller to properly read/write data
+ from/to the flash. If this property is missing,
+ the endianness is chosen by the system
+ (potentially based on extra configuration options).
+
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
+
+Example:
+
+ flash@ff000000 {
+ compatible = "amd,am29lv128ml", "cfi-flash";
+ reg = <ff000000 01000000>;
+ bank-width = <4>;
+ device-width = <1>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ fs@0 {
+ label = "fs";
+ reg = <0 f80000>;
+ };
+ firmware@f80000 {
+ label ="firmware";
+ reg = <f80000 80000>;
+ read-only;
+ };
+ };
+
+Here an example with multiple "reg" tuples:
+
+ flash@f0000000,0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "intel,PC48F4400P0VB", "cfi-flash";
+ reg = <0 0x00000000 0x02000000
+ 0 0x02000000 0x02000000>;
+ bank-width = <2>;
+ partition@0 {
+ label = "test-part1";
+ reg = <0 0x04000000>;
+ };
+ };
+
+An example using SRAM:
+
+ sram@2,0 {
+ compatible = "samsung,k6f1616u6a", "mtd-ram";
+ reg = <2 0 0x00200000>;
+ bank-width = <2>;
+ };
+
+An example using gpio-addrs
+
+ flash@20000000 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "cfi-flash", "jedec-flash";
+ reg = <0x20000000 0x02000000>;
+ ranges = <0 0x00000000 0x02000000
+ 1 0x02000000 0x02000000>;
+ bank-width = <2>;
+ addr-gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
+ partition@0 {
+ label = "test-part1";
+ reg = <0 0x04000000>;
+ };
+ };