arm: kdump: Add DT properties to crash dump kernel's DTB

Pass the following properties to the crash dump kernel, to provide a
modern DT interface between kexec and the crash dump kernel:

  - linux,elfcorehdr: ELF core header segment, similar to the
    "elfcorehdr=" kernel parameter.
  - linux,usable-memory-range: Usable memory reserved for the crash dump
    kernel.
    This makes the memory reservation explicit, so Linux no longer needs
    to mask the program counter, and rely on the "mem=" kernel parameter
    to obtain the start and size of usable memory.

For backwards compatibility, the "elfcorehdr=" and "mem=" kernel
parameters are still appended to the kernel command line.

Loosely based on the ARM64 version by Akashi Takahiro.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms@verge.net.au>

1 files changed, 2 insertions, 0 deletions

diff --git a/kexec/arch/arm/crashdump-arm.h b/kexec/arch/arm/crashdump-arm.h
index 6e87b13..bbdf8bf 100644
--- a/kexec/arch/arm/crashdump-arm.h
+++ b/kexec/arch/arm/crashdump-arm.h
@@ -13,6 +13,8 @@ extern "C" {
 
 
 extern struct memory_ranges usablemem_rgns;
+extern struct memory_range crash_kernel_mem;
+extern struct memory_range elfcorehdr_mem;
 
 struct kexec_info;