diff options
Diffstat (limited to 'Documentation/devicetree/bindings/mtd')
| -rw-r--r-- | Documentation/devicetree/bindings/mtd/microchip,mchp23k256.txt | 18 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/mtd/partition.txt | 32 |
2 files changed, 44 insertions, 6 deletions
diff --git a/Documentation/devicetree/bindings/mtd/microchip,mchp23k256.txt b/Documentation/devicetree/bindings/mtd/microchip,mchp23k256.txt new file mode 100644 index 000000000000..7328eb92a03c --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/microchip,mchp23k256.txt @@ -0,0 +1,18 @@ +* MTD SPI driver for Microchip 23K256 (and similar) serial SRAM + +Required properties: +- #address-cells, #size-cells : Must be present if the device has sub-nodes + representing partitions. +- compatible : Must be one of "microchip,mchp23k256" or "microchip,mchp23lcv1024" +- reg : Chip-Select number +- spi-max-frequency : Maximum frequency of the SPI bus the chip can operate at + +Example: + + spi-sram@0 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "microchip,mchp23k256"; + reg = <0>; + spi-max-frequency = <20000000>; + }; diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt index 81a224da63be..36f3b769a626 100644 --- a/Documentation/devicetree/bindings/mtd/partition.txt +++ b/Documentation/devicetree/bindings/mtd/partition.txt @@ -1,29 +1,49 @@ -Representing flash partitions in devicetree +Flash partitions in device tree +=============================== -Partitions can be represented by sub-nodes of an mtd device. This can be used +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. + +We currently only document a binding for fixed layouts. + + +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 mtd node and should be named +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 mtd device are +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 -mtd device. There are two valid values for both: +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 mtd bank. +- 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 |
