From: James Morse <james.morse@xxxxxxx> Add documentation for linux,crashkernel-base and crashkernel-size, linux,usable-memory-range, and linux,elfcorehdr used by arm64 kexec/kdump to decribe the kdump reserved area, and the elfcorehdr's location within it. Signed-off-by: James Morse <james.morse@xxxxxxx> [takahiro.akashi@xxxxxxxxxx: renamed "usable-memory" to "usable-memory-range", added "linux,crashkernel-base" and "-size" ] Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx> --- Documentation/devicetree/bindings/chosen.txt | 50 ++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt index 6ae9d82..236188a 100644 --- a/Documentation/devicetree/bindings/chosen.txt +++ b/Documentation/devicetree/bindings/chosen.txt @@ -52,3 +52,53 @@ 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,crashkernel-base +linux,crashkernel-size +---------------------- +These properties (currently used on PowerPC and arm64) indicates +the base address and the size, respectively, of the reserved memory +range for crash dump kernel. +e.g. + +/ { + chosen { + linux,crashkernel-base = <0x9 0xf0000000>; + linux,crashkernel-size = <0x0 0x10000000>; + }; +}; + +linux,usable-memory-range +------------------------- + +This property (currently used only on arm64) holds the memory range, +the base address and the size, which can be used as system ram on +the *current* kernel. Note that, if this property is present, any memory +regions under "memory" nodes in DT blob or ones marked as "conventional +memory" in EFI memory map should be ignored. +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. + +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 in elf format. +e.g. + +/ { + chosen { + linux,usable-memory-range = <0x9 0xf0000000 0x0 0x10000000>; + linux,elfcorehdr = <0x9 0xfffff000 0x0 0x800>; + }; +}; -- 2.9.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html