Commit 405fe7aa authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Paul Walmsley
Browse files

riscv: provide a flat image loader 



This allows just loading the kernel at a pre-set address without
qemu going bonkers trying to map the ELF file.

Contains a contribution from Aurabindo Jayamohanan to reuse the
PAGE_OFFSET definition.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarAnup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: fixed checkpatch issue; minor commit
 message fix]
Signed-off-by: default avatarPaul Walmsley <paul.walmsley@sifive.com>
parent 6bd33e1e

arch/riscv/Makefile

+9 −4
Original line number Diff line number Diff line
@@ -83,13 +83,18 @@ PHONY += vdso_install 
vdso_install:

	$(Q)$(MAKE) $(build)=arch/riscv/kernel/vdso $@



all: Image.gz

ifeq ($(CONFIG_RISCV_M_MODE),y)

KBUILD_IMAGE := $(boot)/loader

else

KBUILD_IMAGE := $(boot)/Image.gz

endif

BOOT_TARGETS := Image Image.gz loader



Image: vmlinux

	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@

all:	$(notdir $(KBUILD_IMAGE))



Image.%: Image

$(BOOT_TARGETS): vmlinux

	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@

	@$(kecho) '  Kernel: $(boot)/$@ is ready'



zinstall install:

	$(Q)$(MAKE) $(build)=$(boot) $@

arch/riscv/boot/Makefile

+6 −1
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ 


OBJCOPYFLAGS_Image :=-O binary -R .note -R .note.gnu.build-id -R .comment -S



targets := Image

targets := Image loader



$(obj)/Image: vmlinux FORCE

	$(call if_changed,objcopy)
@@ -24,6 +24,11 @@ $(obj)/Image: vmlinux FORCE 
$(obj)/Image.gz: $(obj)/Image FORCE

	$(call if_changed,gzip)



loader.o: $(src)/loader.S $(obj)/Image



$(obj)/loader: $(obj)/loader.o $(obj)/Image $(obj)/loader.lds FORCE

	$(Q)$(LD) -T $(obj)/loader.lds -o $@ $(obj)/loader.o



install:

	$(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \

	$(obj)/Image System.map "$(INSTALL_PATH)"

arch/riscv/boot/loader.S

0 → 100644
+8 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */



	.align 4

	.section .payload, "ax", %progbits

	.globl _start

_start:

	.incbin "arch/riscv/boot/Image"

arch/riscv/boot/loader.lds.S

0 → 100644
+16 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */



#include <asm/page.h>



OUTPUT_ARCH(riscv)

ENTRY(_start)



SECTIONS

{

	. = PAGE_OFFSET;



	.payload : {

		*(.payload)

		. = ALIGN(8);

	}

}

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