34 lines
1.5 KiB
Plaintext
34 lines
1.5 KiB
Plaintext
|
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.
|
||
|
|
|
||
|
|
|
||
|
|
Deprecated: partitions defined in flash 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.
|