From 405fe7aa0dbaa6cb8cfe62771eee67076d30aca1 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 28 Oct 2019 13:10:42 +0100 Subject: [PATCH] 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: Christoph Hellwig Reviewed-by: Anup Patel [paul.walmsley@sifive.com: fixed checkpatch issue; minor commit message fix] Signed-off-by: Paul Walmsley --- arch/riscv/Makefile | 13 +++++++++---- arch/riscv/boot/Makefile | 7 ++++++- arch/riscv/boot/loader.S | 8 ++++++++ arch/riscv/boot/loader.lds.S | 16 ++++++++++++++++ 4 files changed, 39 insertions(+), 5 deletions(-) create mode 100644 arch/riscv/boot/loader.S create mode 100644 arch/riscv/boot/loader.lds.S diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index f5e914210245..b9009a2fbaf5 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -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) $@ diff --git a/arch/riscv/boot/Makefile b/arch/riscv/boot/Makefile index 0990a9fdbe5d..433ccbcabb23 100644 --- a/arch/riscv/boot/Makefile +++ b/arch/riscv/boot/Makefile @@ -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)" diff --git a/arch/riscv/boot/loader.S b/arch/riscv/boot/loader.S new file mode 100644 index 000000000000..dcf88cf44dc1 --- /dev/null +++ b/arch/riscv/boot/loader.S @@ -0,0 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + + .align 4 + .section .payload, "ax", %progbits + .globl _start +_start: + .incbin "arch/riscv/boot/Image" + diff --git a/arch/riscv/boot/loader.lds.S b/arch/riscv/boot/loader.lds.S new file mode 100644 index 000000000000..47a5003c2e28 --- /dev/null +++ b/arch/riscv/boot/loader.lds.S @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include + +OUTPUT_ARCH(riscv) +ENTRY(_start) + +SECTIONS +{ + . = PAGE_OFFSET; + + .payload : { + *(.payload) + . = ALIGN(8); + } +}