[RFC 10/10] arm: kdump: add CONFIG_CRASH_DUMP Kconfig option

[Mika Westerberg]

Add CONFIG_CRASH_DUMP configuration option which is used by dump capture
kernels. This option also forces one to link kernel in different address (by
default it is 0x02008000).

Signed-off-by: Mika Westerberg <ext-mika.1.westerberg at nokia.com>
---
 arch/arm/Kconfig  |   11 +++++++++++
 arch/arm/Makefile |   10 ++++++++++
 2 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index c5408bf..4940cff 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1466,6 +1466,17 @@ config ATAGS_PROC
 	  Should the atags used to boot the kernel be exported in an "atags"
 	  file in procfs. Useful with kexec.
 
+config CRASH_DUMP
+	bool "Build kdump crash kernel (EXPERIMENTAL)"
+	depends on EXPERIMENTAL
+	help
+	  Build a kernel suitable for use as kdump capture kernel. This should
+	  be set only on dump capture kernels. Note that dump capture kernel
+	  must be loaded into different address than the primary kernel. See
+	  file arch/arm/Makefile how to change this.
+
+	  For more details see Documentation/kdump/kdump.txt
+
 endmenu
 
 menu "CPU Power Management"
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index ed820e7..848dee9 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -109,6 +109,16 @@ CHECKFLAGS	+= -D__arm__
 #Default value
 head-y		:= arch/arm/kernel/head$(MMUEXT).o arch/arm/kernel/init_task.o
 textofs-y	:= 0x00008000
+
+#
+# Dump capture kernels are linked by default to address 0x02008000 to prevent
+# them from stepping over the primary kernel memory. Adjust this if you need to
+# link it into a different address.
+#
+# Remember also check your $(MACHINE)/Makefile.boot to correspond this.
+#
+textofs-$(CONFIG_CRASH_DUMP) := 0x02008000
+
 textofs-$(CONFIG_ARCH_CLPS711X) := 0x00028000
 # SA1111 DMA bug: we don't want the kernel to live in precious DMA-able memory
 ifeq ($(CONFIG_ARCH_SA1100),y)
-- 
1.5.6.5