riscv: Enable building for EFI
Mimicking arm64 support, add configure and makefile changes to build
for EFI. Since the linker script is replaced also replace the initial
cstart code (also done like arm64). Finally, provide a stub for
setup_efi() in order to allow compiling to complete (even though
tests can't yet run).
Signed-off-by: Andrew Jones <andrew.jones@linux.dev>
diff --git a/configure b/configure
index 51edee8..c1d0fe4 100755
--- a/configure
+++ b/configure
@@ -231,7 +231,8 @@
fi
fi
-if [ "$efi" ] && [ "$arch" != "x86_64" ] && [ "$arch" != "arm64" ]; then
+if [ "$efi" ] && [ "$arch" != "x86_64" ] &&
+ [ "$arch" != "arm64" ] && [ "$arch" != "riscv64" ]; then
echo "--[enable|disable]-efi is not supported for $arch"
usage
fi
diff --git a/lib/riscv/asm/setup.h b/lib/riscv/asm/setup.h
index e58dd53..dfc8875 100644
--- a/lib/riscv/asm/setup.h
+++ b/lib/riscv/asm/setup.h
@@ -12,4 +12,9 @@
void io_init(void);
void setup(const void *fdt, phys_addr_t freemem_start);
+#ifdef CONFIG_EFI
+#include <efi.h>
+static inline efi_status_t setup_efi(efi_bootinfo_t *efi_bootinfo) { return 0; }
+#endif
+
#endif /* _ASMRISCV_SETUP_H_ */
diff --git a/riscv/Makefile b/riscv/Makefile
index 85bbca1..919a3eb 100644
--- a/riscv/Makefile
+++ b/riscv/Makefile
@@ -17,7 +17,8 @@
all: $(tests)
-$(TEST_DIR)/sieve.elf: AUXFLAGS = 0x1
+# When built for EFI sieve needs extra memory, run with e.g. '-m 256' on QEMU
+$(TEST_DIR)/sieve.$(exe): AUXFLAGS = 0x1
cstart.o = $(TEST_DIR)/cstart.o
@@ -85,7 +86,29 @@
-DPROGNAME=\"$(notdir $(@:.aux.o=.$(exe)))\" -DAUXFLAGS=$(AUXFLAGS)
ifeq ($(CONFIG_EFI),y)
- # TODO
+# avoid jump tables before all relocations have been processed
+riscv/efi/reloc_riscv64.o: CFLAGS += -fno-jump-tables
+cflatobjs += riscv/efi/reloc_riscv64.o
+cflatobjs += lib/acpi.o
+cflatobjs += lib/efi.o
+
+.PRECIOUS: %.so
+
+%.so: EFI_LDFLAGS += -defsym=EFI_SUBSYSTEM=0xa --no-undefined
+%.so: %.o $(FLATLIBS) $(SRCDIR)/riscv/efi/elf_riscv64_efi.lds $(cstart.o) %.aux.o
+ $(LD) $(EFI_LDFLAGS) -o $@ -T $(SRCDIR)/riscv/efi/elf_riscv64_efi.lds \
+ $(filter %.o, $^) $(FLATLIBS) $(EFI_LIBS)
+
+%.efi: %.so
+ $(call arch_elf_check, $^)
+ $(OBJCOPY) --only-keep-debug $^ $@.debug
+ $(OBJCOPY) --strip-debug $^
+ $(OBJCOPY) --add-gnu-debuglink=$@.debug $^
+ $(OBJCOPY) \
+ -j .text -j .sdata -j .data -j .rodata -j .dynamic -j .dynsym \
+ -j .rel -j .rela -j .rel.* -j .rela.* -j .rel* -j .rela* \
+ -j .reloc \
+ -O binary $^ $@
else
%.elf: LDFLAGS += -pie -n -z notext
%.elf: %.o $(FLATLIBS) $(SRCDIR)/riscv/flat.lds $(cstart.o) %.aux.o
diff --git a/riscv/cstart.S b/riscv/cstart.S
index c935467..10b5da5 100644
--- a/riscv/cstart.S
+++ b/riscv/cstart.S
@@ -42,6 +42,9 @@
9997:
.endm
+#ifdef CONFIG_EFI
+#include "efi/crt0-efi-riscv64.S"
+#else
.section .init
/*
@@ -109,6 +112,7 @@
call exit
j halt
+#endif /* !CONFIG_EFI */
.text
.balign 4
