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device_tree_standard_properties

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Overview

Standard properties of devicetrees.

Properties

compatible

model

phandle

status

#address-cells, #size-calls

The #address-cells and #size-cells properties are not inherited from ancestors in the devicetree. They shall be explicitly defined.

A DTSpec-compliant boot program shall supply #address-cells and #size-cells on all nodes that have children.

If missing, a client program should assume a default value of 2 for #address-cells, and a value of 1 for #size-cells.

reg

The reg property describes the address of the device’s resources within the address space defined by its parent bus. Most commonly this means the offsets and lengths of memory-mapped IO register blocks, but may have a different meaning on some bus types. Addresses in the address space defined by the root node are CPU real addresses.

The value is a <prop-encoded-array>, composed of an arbitrary number of pairs of address and length, <address length>. The number of <u32> cells required to specify the address and length are bus-specific and are specified by the #address-cells and #size-cells properties in the parent of the device node. If the parent node specifies a value of 0 for #size-cells, the length field in the value of reg shall be omitted.

virtual-reg

Seems to be PowerPC only.

ranges

dma-ranges

device_tree_standard_properties.1542545714.txt.gz · Last modified: 2018/11/18 12:55 by rpjday