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-The chosen node
----------------
-
-The chosen node does not represent a real device, but serves as a place
-for passing data between firmware and the operating system, like boot
-arguments. Data in the chosen node does not represent the hardware.
-
-The following properties are recognized:
-
-
-kaslr-seed
------------
-
-This property is used when booting with CONFIG_RANDOMIZE_BASE as the
-entropy used to randomize the kernel image base address location. Since
-it is used directly, this value is intended only for KASLR, and should
-not be used for other purposes (as it may leak information about KASLR
-offsets). It is parsed as a u64 value, e.g.
-
-/ {
- chosen {
- kaslr-seed = <0xfeedbeef 0xc0def00d>;
- };
-};
-
-Note that if this property is set from UEFI (or a bootloader in EFI
-mode) when EFI_RNG_PROTOCOL is supported, it will be overwritten by
-the Linux EFI stub (which will populate the property itself, using
-EFI_RNG_PROTOCOL).
-
-stdout-path
------------
-
-Device trees may specify the device to be used for boot console output
-with a stdout-path property under /chosen, as described in the Devicetree
-Specification, e.g.
-
-/ {
- chosen {
- stdout-path = "/serial@f00:115200";
- };
-
- serial@f00 {
- compatible = "vendor,some-uart";
- reg = <0xf00 0x10>;
- };
-};
-
-If the character ":" is present in the value, this terminates the path.
-The meaning of any characters following the ":" is device-specific, and
-must be specified in the relevant binding documentation.
-
-For UART devices, the preferred binding is a string in the form:
-
- <baud>{<parity>{<bits>{<flow>}}}
-
-where
-
- baud - baud rate in decimal
- parity - 'n' (none), 'o', (odd) or 'e' (even)
- bits - number of data bits
- flow - 'r' (rts)
-
-For example: 115200n8r
-
-Implementation note: Linux will look for the property "linux,stdout-path" or
-on PowerPC "stdout" if "stdout-path" is not found. However, the
-"linux,stdout-path" and "stdout" properties are deprecated. New platforms
-should only use the "stdout-path" property.
-
-linux,booted-from-kexec
------------------------
-
-This property is set (currently only on PowerPC, and only needed on
-book3e) by some versions of kexec-tools to tell the new kernel that it
-is being booted by kexec, as the booting environment may differ (e.g.
-a different secondary CPU release mechanism)
-
-linux,usable-memory-range
--------------------------
-
-This property (arm64 only) holds a base address and size, describing a
-limited region in which memory may be considered available for use by
-the kernel. Memory outside of this range is not available for use.
-
-This property describes a limitation: memory within this range is only
-valid when also described through another mechanism that the kernel
-would otherwise use to determine available memory (e.g. memory nodes
-or the EFI memory map). Valid memory may be sparse within the range.
-e.g.
-
-/ {
- chosen {
- linux,usable-memory-range = <0x9 0xf0000000 0x0 0x10000000>;
- };
-};
-
-The main usage is for crash dump kernel to identify its own usable
-memory and exclude, at its boot time, any other memory areas that are
-part of the panicked kernel's memory.
-
-While this property does not represent a real hardware, the address
-and the size are expressed in #address-cells and #size-cells,
-respectively, of the root node.
-
-linux,elfcorehdr
-----------------
-
-This property (currently used only on arm64) holds the memory range,
-the address and the size, of the elf core header which mainly describes
-the panicked kernel's memory layout as PT_LOAD segments of elf format.
-e.g.
-
-/ {
- chosen {
- linux,elfcorehdr = <0x9 0xfffff000 0x0 0x800>;
- };
-};
-
-While this property does not represent a real hardware, the address
-and the size are expressed in #address-cells and #size-cells,
-respectively, of the root node.
-
-linux,initrd-start and linux,initrd-end
----------------------------------------
-
-These properties hold the physical start and end address of an initrd that's
-loaded by the bootloader. Note that linux,initrd-start is inclusive, but
-linux,initrd-end is exclusive.
-e.g.
-
-/ {
- chosen {
- linux,initrd-start = <0x82000000>;
- linux,initrd-end = <0x82800000>;
- };
-};