Commit ec758f98 authored by Helge Deller's avatar Helge Deller
Browse files

parisc: add CONFIG_MLONGCALLS option to enable linkage of huge vmlinux executables 



When building a 64bit kernel which includes all necessary drivers and
filesystems the vmlinux kernel often gets so huge, that the linker won't
be able to resolve the branch stubs. This patch overcomes this limit by
providing an option to compile the kernel with the -mlong-calls compiler
option.

Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 1c4c6597

arch/parisc/Kconfig

+17 −0
Original line number Diff line number Diff line
@@ -161,6 +161,23 @@ config PREFETCH 
	def_bool y

	depends on PA8X00 || PA7200



config MLONGCALLS

	bool "Enable the -mlong-calls compiler option for big kernels"

	def_bool y if (!MODULES)

	depends on PA8X00

	help

	  If you configure the kernel to include many drivers built-in instead

	  as modules, the kernel executable may become too big, so that the

	  linker will not be able to resolve some long branches and fails to link

	  your vmlinux kernel. In that case enabling this option will help you

	  to overcome this limit by using the -mlong-calls compiler option.



	  Usually you want to say N here, unless you e.g. want to build

	  a kernel which includes all necessary drivers built-in and which can

	  be used for TFTP booting without the need to have an initrd ramdisk.



	  Enabling this option will probably slow down your kernel.



config 64BIT

	bool "64-bit kernel"

	depends on PA8X00

arch/parisc/Makefile

+4 −0
Original line number Diff line number Diff line
@@ -64,6 +64,10 @@ ifndef CONFIG_FUNCTION_TRACER 
  cflags-y	+= -ffunction-sections

endif



# Use long jumps instead of long branches (needed if your linker fails to

# link a too big vmlinux executable)

cflags-$(CONFIG_MLONGCALLS)	+= -mlong-calls



# select which processor to optimise for

cflags-$(CONFIG_PA7100)		+= -march=1.1 -mschedule=7100

cflags-$(CONFIG_PA7200)		+= -march=1.1 -mschedule=7200

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