From b3266bd6ff52efb9e57c7fbfff4c8f7363dfaab3 Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Tue, 8 May 2012 21:22:25 +0300 Subject: [PATCH] x86, realmode: realmode.bin infrastructure Create realmode.bin and realmode.relocs files. Piggy pack them into relocatable object that will be included into .init.data section of the main kernel image. The first file includes binary image of the real-mode code. The latter file includes all relocations. The layout of the binary image is specified in realmode.lds.S. The makefile generates pa_ prefixed symbols for each exported global. These are used in 32-bit code and in realmode header to define symbols that need to be relocated. Signed-off-by: Jarkko Sakkinen Link: http://lkml.kernel.org/r/1336501366-28617-3-git-send-email-jarkko.sakkinen@intel.com Originally-by: H. Peter Anvin Signed-off-by: H. Peter Anvin --- arch/x86/Kbuild | 2 +- arch/x86/realmode/Makefile | 20 +++++++++ arch/x86/realmode/rm/.gitignore | 3 ++ arch/x86/realmode/rm/Makefile | 63 ++++++++++++++++++++++++++ arch/x86/realmode/rm/header.S | 16 +++++++ arch/x86/realmode/rm/realmode.lds.S | 68 +++++++++++++++++++++++++++++ arch/x86/realmode/rmpiggy.S | 18 ++++++++ 7 files changed, 189 insertions(+), 1 deletion(-) create mode 100644 arch/x86/realmode/Makefile create mode 100644 arch/x86/realmode/rm/.gitignore create mode 100644 arch/x86/realmode/rm/Makefile create mode 100644 arch/x86/realmode/rm/header.S create mode 100644 arch/x86/realmode/rm/realmode.lds.S create mode 100644 arch/x86/realmode/rmpiggy.S diff --git a/arch/x86/Kbuild b/arch/x86/Kbuild index 0e9dec6cadd1..e5287d8517aa 100644 --- a/arch/x86/Kbuild +++ b/arch/x86/Kbuild @@ -1,4 +1,3 @@ - obj-$(CONFIG_KVM) += kvm/ # Xen paravirtualization support @@ -7,6 +6,7 @@ obj-$(CONFIG_XEN) += xen/ # lguest paravirtualization support obj-$(CONFIG_LGUEST_GUEST) += lguest/ +obj-y += realmode/ obj-y += kernel/ obj-y += mm/ diff --git a/arch/x86/realmode/Makefile b/arch/x86/realmode/Makefile new file mode 100644 index 000000000000..f22a4f8d99d6 --- /dev/null +++ b/arch/x86/realmode/Makefile @@ -0,0 +1,20 @@ +# +# arch/x86/realmode/Makefile +# +# This file is subject to the terms and conditions of the GNU General Public +# License. See the file "COPYING" in the main directory of this archive +# for more details. +# +# + +subdir- := rm + +obj-y += rmpiggy.o + +$(obj)/rmpiggy.o: $(obj)/rm/realmode.relocs $(obj)/rm/realmode.bin + +$(obj)/rm/realmode.bin: FORCE + $(Q)$(MAKE) $(build)=$(obj)/rm $@ + +$(obj)/rm/realmode.relocs: FORCE + $(Q)$(MAKE) $(build)=$(obj)/rm $@ diff --git a/arch/x86/realmode/rm/.gitignore b/arch/x86/realmode/rm/.gitignore new file mode 100644 index 000000000000..b6ed3a2555cb --- /dev/null +++ b/arch/x86/realmode/rm/.gitignore @@ -0,0 +1,3 @@ +pasyms.h +realmode.lds +realmode.relocs diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile new file mode 100644 index 000000000000..7c3f202cbccf --- /dev/null +++ b/arch/x86/realmode/rm/Makefile @@ -0,0 +1,63 @@ +# +# arch/x86/realmode/Makefile +# +# This file is subject to the terms and conditions of the GNU General Public +# License. See the file "COPYING" in the main directory of this archive +# for more details. +# +# + +subdir- := wakeup + +always := realmode.bin + +realmode-y += header.o + +targets += $(realmode-y) + +REALMODE_OBJS = $(addprefix $(obj)/,$(realmode-y)) + +sed-pasyms := -n -r -e 's/^([0-9a-fA-F]+) [ABCDGRSTVW] (.+)$$/pa_\2 = \2;/p' + +quiet_cmd_pasyms = PASYMS $@ + cmd_pasyms = $(NM) $(filter-out FORCE,$^) | \ + sed $(sed-pasyms) | sort | uniq > $@ + +$(obj)/pasyms.h: $(REALMODE_OBJS) FORCE + $(call if_changed,pasyms) + +$(obj)/realmode.lds: $(obj)/pasyms.h + +LDFLAGS_realmode.elf := --emit-relocs -T +CPPFLAGS_realmode.lds += -P -C -I$(obj) + +$(obj)/realmode.elf: $(obj)/realmode.lds $(REALMODE_OBJS) FORCE + $(call if_changed,ld) + +OBJCOPYFLAGS_realmode.bin := -O binary + +$(obj)/realmode.bin: $(obj)/realmode.elf + $(call if_changed,objcopy) + +quiet_cmd_relocs = RELOCS $@ + cmd_relocs = scripts/x86-relocs --realmode $< > $@ +$(obj)/realmode.relocs: $(obj)/realmode.elf FORCE + $(call if_changed,relocs) + +# --------------------------------------------------------------------------- + +# How to compile the 16-bit code. Note we always compile for -march=i386, +# that way we can complain to the user if the CPU is insufficient. +KBUILD_CFLAGS := $(LINUXINCLUDE) -m32 -g -Os -D_SETUP -D__KERNEL__ \ + -DDISABLE_BRANCH_PROFILING \ + -Wall -Wstrict-prototypes \ + -march=i386 -mregparm=3 \ + -include $(srctree)/$(src)/../../boot/code16gcc.h \ + -fno-strict-aliasing -fomit-frame-pointer \ + $(call cc-option, -ffreestanding) \ + $(call cc-option, -fno-toplevel-reorder,\ + $(call cc-option, -fno-unit-at-a-time)) \ + $(call cc-option, -fno-stack-protector) \ + $(call cc-option, -mpreferred-stack-boundary=2) +KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__ +GCOV_PROFILE := n diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S new file mode 100644 index 000000000000..7be17f2c65a3 --- /dev/null +++ b/arch/x86/realmode/rm/header.S @@ -0,0 +1,16 @@ +/* + * Real-mode blob header; this should match realmode.h and be + * readonly; for mutable data instead add pointers into the .data + * or .bss sections as appropriate. + */ + +#include +#include + + .section ".header", "a" + +ENTRY(real_mode_header) + .long pa_text_start + .long pa_ro_end + .long pa_end +END(real_mode_header) diff --git a/arch/x86/realmode/rm/realmode.lds.S b/arch/x86/realmode/rm/realmode.lds.S new file mode 100644 index 000000000000..c5b8a4f31ba3 --- /dev/null +++ b/arch/x86/realmode/rm/realmode.lds.S @@ -0,0 +1,68 @@ +/* + * realmode.lds.S + * + * Linker script for the real-mode code + */ + +#include + +#undef i386 + +OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386") +OUTPUT_ARCH(i386) + +SECTIONS +{ + real_mode_seg = 0; + + . = 0; + .header : { + pa_real_mode_base = .; + *(.header) + } + + . = ALIGN(4); + .rodata : { + *(.rodata) + *(.rodata.*) + } + + . = ALIGN(PAGE_SIZE); + .text : { + pa_text_start = .; + *(.text) + *(.text.*) + } + + .text32 : { + *(.text32) + *(.text32.*) + pa_ro_end = .; + } + + . = ALIGN(PAGE_SIZE); + .data : { + *(.data) + *(.data.*) + } + + . = ALIGN(128); + .bss : { + *(.bss*) + } + + /* End signature for integrity checking */ + . = ALIGN(4); + .signature : { + *(.signature) + pa_end = .; + } + + /DISCARD/ : { + *(.note*) + *(.debug*) + *(.eh_frame*) + } + +#include "pasyms.h" +} diff --git a/arch/x86/realmode/rmpiggy.S b/arch/x86/realmode/rmpiggy.S new file mode 100644 index 000000000000..6047d7f604cf --- /dev/null +++ b/arch/x86/realmode/rmpiggy.S @@ -0,0 +1,18 @@ +/* + * Wrapper script for the realmode binary as a transport object + * before copying to low memory. + */ +#include +#include + + .section ".init.data","aw" + + .balign PAGE_SIZE + +ENTRY(real_mode_blob) + .incbin "arch/x86/realmode/rm/realmode.bin" +END(real_mode_blob) + +ENTRY(real_mode_relocs) + .incbin "arch/x86/realmode/rm/realmode.relocs" +END(real_mode_relocs)