Absolute calls from initram were only working from the file which had _MAINOBJECT #defined. Calls from all other files ended up in nirvana because the compiler was not able to calculate the address of the wrapper for the absolute call. The linker tried, but failed miserably. Use the -combine flag and compile all of initram at once. This enables GCC to calculate the address of the abscall wrapper, resulting in working code.
Segher Boessenkool thinks the patched code works only by accident because GCC has no way to specify generation of XIP code. According to him, future GCC versions or other circumstances may break the code.
While this patch makes code work for now, it does NOT check whether the generated code tries to write to memory outside the stack (general writable data). That will of course fail, but I hope porters are smart enough to avoid that.
Signed-off-by: Carl-Daniel Hailfinger c-d.hailfinger.devel.2006@gmx.net
Index: LinuxBIOSv3-xiptest-working/mainboard/adl/msm800sev/Makefile =================================================================== --- LinuxBIOSv3-xiptest-working/mainboard/adl/msm800sev/Makefile (revision 535) +++ LinuxBIOSv3-xiptest-working/mainboard/adl/msm800sev/Makefile (working copy) @@ -21,10 +21,10 @@
STAGE0_MAINBOARD_OBJ := $(obj)/mainboard/$(MAINBOARDDIR)/stage1.o
-INITRAM_OBJ = $(obj)/mainboard/$(MAINBOARDDIR)/initram.o \ - $(obj)/northbridge/amd/geodelx/raminit.o \ - $(obj)/southbridge/amd/cs5536/smbus_initram.o \ - $(obj)/arch/x86/geodelx/geodelx.o +INITRAM_OBJ = $(src)/mainboard/$(MAINBOARDDIR)/initram.c \ + $(src)/northbridge/amd/geodelx/raminit.c \ + $(src)/southbridge/amd/cs5536/smbus_initram.c \ + $(src)/arch/x86/geodelx/geodelx.c
STAGE2_MAINBOARD_OBJ =
Index: LinuxBIOSv3-xiptest-working/mainboard/amd/norwich/Makefile =================================================================== --- LinuxBIOSv3-xiptest-working/mainboard/amd/norwich/Makefile (revision 535) +++ LinuxBIOSv3-xiptest-working/mainboard/amd/norwich/Makefile (working copy) @@ -21,10 +21,10 @@
STAGE0_MAINBOARD_OBJ := $(obj)/mainboard/$(MAINBOARDDIR)/stage1.o
-INITRAM_OBJ = $(obj)/mainboard/$(MAINBOARDDIR)/initram.o \ - $(obj)/northbridge/amd/geodelx/raminit.o \ - $(obj)/southbridge/amd/cs5536/smbus_initram.o \ - $(obj)/arch/x86/geodelx/geodelx.o +INITRAM_OBJ = $(src)/mainboard/$(MAINBOARDDIR)/initram.c \ + $(src)/northbridge/amd/geodelx/raminit.c \ + $(src)/southbridge/amd/cs5536/smbus_initram.c \ + $(src)/arch/x86/geodelx/geodelx.c
STAGE2_MAINBOARD_OBJ =
Index: LinuxBIOSv3-xiptest-working/mainboard/artecgroup/dbe61/Makefile =================================================================== --- LinuxBIOSv3-xiptest-working/mainboard/artecgroup/dbe61/Makefile (revision 535) +++ LinuxBIOSv3-xiptest-working/mainboard/artecgroup/dbe61/Makefile (working copy) @@ -21,8 +21,8 @@
STAGE0_MAINBOARD_OBJ := $(obj)/mainboard/$(MAINBOARDDIR)/stage1.o
-INITRAM_OBJ = $(obj)/mainboard/$(MAINBOARDDIR)/initram.o \ - $(obj)/arch/x86/geodelx/geodelx.o +INITRAM_OBJ = $(src)/mainboard/$(MAINBOARDDIR)/initram.c \ + $(src)/arch/x86/geodelx/geodelx.c
STAGE2_MAINBOARD_OBJ =
Index: LinuxBIOSv3-xiptest-working/mainboard/pcengines/alix1c/Makefile =================================================================== --- LinuxBIOSv3-xiptest-working/mainboard/pcengines/alix1c/Makefile (revision 535) +++ LinuxBIOSv3-xiptest-working/mainboard/pcengines/alix1c/Makefile (working copy) @@ -21,9 +21,9 @@
STAGE0_MAINBOARD_OBJ := $(obj)/mainboard/$(MAINBOARDDIR)/stage1.o
-INITRAM_OBJ = $(obj)/mainboard/$(MAINBOARDDIR)/initram.o \ - $(obj)/northbridge/amd/geodelx/raminit.o \ - $(obj)/arch/x86/geodelx/geodelx.o +INITRAM_OBJ = $(src)/mainboard/$(MAINBOARDDIR)/initram.c \ + $(src)/northbridge/amd/geodelx/raminit.c \ + $(src)/arch/x86/geodelx/geodelx.c
STAGE2_MAINBOARD_OBJ =
Index: LinuxBIOSv3-xiptest-working/mainboard/emulation/qemu-x86/Makefile =================================================================== --- LinuxBIOSv3-xiptest-working/mainboard/emulation/qemu-x86/Makefile (revision 535) +++ LinuxBIOSv3-xiptest-working/mainboard/emulation/qemu-x86/Makefile (working copy) @@ -28,8 +28,8 @@ # directory and is built from what was auto.c in v2. #
-INITRAM_OBJ = $(obj)/mainboard/$(MAINBOARDDIR)/initram.o \ - $(obj)/mainboard/$(MAINBOARDDIR)/initram_printktest.o +INITRAM_OBJ = $(src)/mainboard/$(MAINBOARDDIR)/initram.c \ + $(src)/mainboard/$(MAINBOARDDIR)/initram_printktest.c
STAGE2_MAINBOARD_OBJ = vga.o
Index: LinuxBIOSv3-xiptest-working/Rules.make =================================================================== --- LinuxBIOSv3-xiptest-working/Rules.make (revision 535) +++ LinuxBIOSv3-xiptest-working/Rules.make (working copy) @@ -78,13 +78,3 @@ $(Q)printf " CC $(subst $(shell pwd)/,,$(@))\n" $(Q)$(CC) $(INITCFLAGS) -c $< -o $@
-# -# RAM initialization code can not be linked at a specific address, -# hence it has to be executed in place (XIP) position independently. -# - -$(obj)/%_xip.o: $(src)/%.c - $(Q)mkdir -p $(dir $@) - $(Q)printf " CC $(subst $(shell pwd)/,,$(@)) (XIP)\n" - $(Q)$(CC) $(INITCFLAGS) -D_SHARED -fPIE -c $< -o $@ - Index: LinuxBIOSv3-xiptest-working/arch/x86/stage1.c =================================================================== --- LinuxBIOSv3-xiptest-working/arch/x86/stage1.c (revision 535) +++ LinuxBIOSv3-xiptest-working/arch/x86/stage1.c (working copy) @@ -137,17 +137,17 @@ // find first initram if (check_normal_boot_flag()) { printk(BIOS_DEBUG, "Choosing normal boot.\n"); - ret = execute_in_place(&archive, "normal/initram.o/segment0"); + ret = execute_in_place(&archive, "normal/initram/segment0"); } else { printk(BIOS_DEBUG, "Choosing fallback boot.\n"); - ret = execute_in_place(&archive, "fallback/initram.o/segment0"); + ret = execute_in_place(&archive, "fallback/initram/segment0"); /* Try a normal boot if fallback doesn't exist in the lar. * TODO: There are other ways to do this. * It could be ifdef or the boot flag could be forced. */ if (ret) { printk(BIOS_DEBUG, "Fallback failed. Try normal boot\n"); - ret = execute_in_place(&archive, "normal/initram.o/segment0"); + ret = execute_in_place(&archive, "normal/initram/segment0"); } }
Index: LinuxBIOSv3-xiptest-working/arch/x86/Makefile =================================================================== --- LinuxBIOSv3-xiptest-working/arch/x86/Makefile (revision 535) +++ LinuxBIOSv3-xiptest-working/arch/x86/Makefile (working copy) @@ -36,7 +36,7 @@
ROM_SIZE := $(shell expr $(CONFIG_LINUXBIOS_ROMSIZE_KB) * 1024)
-LARFILES := nocompress:normal/initram.o normal/stage2.o nocompress:normal/option_table +LARFILES := nocompress:normal/initram normal/stage2.o nocompress:normal/option_table ifneq ($(CONFIG_PAYLOAD_NONE),y) LARFILES += normal/payload endif @@ -57,11 +57,11 @@ COMPRESSFLAG := -C nrv2b endif
-$(obj)/linuxbios.rom $(obj)/linuxbios.map: $(obj)/linuxbios.bootblock $(obj)/util/lar/lar lzma nrv2b $(obj)/linuxbios.initram.o $(obj)/linuxbios.stage2.o $(obj)/option_table +$(obj)/linuxbios.rom $(obj)/linuxbios.map: $(obj)/linuxbios.bootblock $(obj)/util/lar/lar lzma nrv2b $(obj)/linuxbios.initram $(obj)/linuxbios.stage2.o $(obj)/option_table $(Q)rm -rf $(obj)/lar.tmp $(Q)mkdir $(obj)/lar.tmp $(Q)mkdir $(obj)/lar.tmp/normal - $(Q)cp $(obj)/linuxbios.initram.o $(obj)/lar.tmp/normal/initram.o + $(Q)cp $(obj)/linuxbios.initram $(obj)/lar.tmp/normal/initram $(Q)cp $(obj)/linuxbios.stage2.o $(obj)/lar.tmp/normal/stage2.o $(Q)cp $(obj)/option_table $(obj)/lar.tmp/normal/option_table ifeq ($(CONFIG_PAYLOAD_NONE),y) @@ -232,12 +232,14 @@ $(Q)printf " AS $(subst $(shell pwd)/,,$(@))\n" $(Q)$(AS) $(obj)/arch/x86/stage0_asm.s -o $@
-$(obj)/linuxbios.initram.o $(obj)/linuxbios.initram.map: $(obj)/stage0.init $(obj)/stage0-prefixed.o $(patsubst %.o,%_xip.o,$(INITRAM_OBJ)) +$(obj)/linuxbios.initram $(obj)/linuxbios.initram.map: $(obj)/stage0.init $(obj)/stage0-prefixed.o $(INITRAM_OBJ) + $(Q)printf " CC $(subst $(shell pwd)/,,$(@)) (XIP)\n" + $(Q)$(CC) $(INITCFLAGS) -D_SHARED -fPIE -c -combine $(INITRAM_OBJ) -o $(obj)/linuxbios.initram_partiallylinked.o $(Q)# initram links against stage0 $(Q)printf " LD $(subst $(shell pwd)/,,$(@))\n" $(Q)$(LD) -Ttext 0 --entry main -N -R $(obj)/stage0-prefixed.o \ - $(patsubst %.o,%_xip.o,$(INITRAM_OBJ)) -o $(obj)/linuxbios.initram.o + $(obj)/linuxbios.initram_partiallylinked.o -o $(obj)/linuxbios.initram $(Q)printf " NM $(subst $(shell pwd)/,,$(@))\n" - $(Q)$(NM) $(obj)/linuxbios.initram.o | sort -u > $(obj)/linuxbios.initram.map + $(Q)$(NM) $(obj)/linuxbios.initram | sort -u > $(obj)/linuxbios.initram.map
endif