riscv: tools: Prelink u-boot

Add prelink-riscv to arrange .rela.dyn and .rela.got
in compile time. So that u-boot can be directly
executed without fixup.

Signed-off-by: Chih-Mao Chen <cmchen@andestech.com>
Signed-off-by: Rick Chen <rick@andestech.com>
Signed-off-by: Rick Chen <rickchen36@gmail.com>
Signed-off-by: Greentime Hu <green.hu@gmail.com>

1 files changed, 102 insertions, 0 deletions

diff --git a/tools/prelink-riscv.c b/tools/prelink-riscv.c
new file mode 100644
index 0000000000..632d2da6ba
--- /dev/null
+++ b/tools/prelink-riscv.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2017 Andes Technology
+ * Chih-Mao Chen <cmchen@andestech.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ *
+ * Statically process runtime relocations on RISC-V ELF images
+ * so that it can be directly executed when loaded at LMA
+ * without fixup. Both RV32 and RV64 are supported.
+ */
+
+#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
+#error "Only little-endian host is supported"
+#endif
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <elf.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#ifndef EM_RISCV
+#define EM_RISCV 243
+#endif
+
+#ifndef R_RISCV_32
+#define R_RISCV_32 1
+#endif
+
+#ifndef R_RISCV_64
+#define R_RISCV_64 2
+#endif
+
+#ifndef R_RISCV_RELATIVE
+#define R_RISCV_RELATIVE 3
+#endif
+
+const char *argv0;
+
+#define die(fmt, ...) \
+	do { \
+		fprintf(stderr, "%s: " fmt "\n", argv0, ## __VA_ARGS__); \
+		exit(EXIT_FAILURE); \
+	} while (0)
+
+#define PRELINK_INC_BITS 32
+#include "prelink-riscv.inc"
+#undef PRELINK_INC_BITS
+
+#define PRELINK_INC_BITS 64
+#include "prelink-riscv.inc"
+#undef PRELINK_INC_BITS
+
+int main(int argc, const char *const *argv)
+{
+	argv0 = argv[0];
+
+	if (argc < 2) {
+		fprintf(stderr, "Usage: %s <u-boot>\n", argv0);
+		exit(EXIT_FAILURE);
+	}
+
+	int fd = open(argv[1], O_RDWR, 0);
+
+	if (fd < 0)
+		die("Cannot open %s: %s", argv[1], strerror(errno));
+
+	struct stat st;
+
+	if (fstat(fd, &st) < 0)
+		die("Cannot stat %s: %s", argv[1], strerror(errno));
+
+	void *data =
+		mmap(0, st.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+
+	if (data == MAP_FAILED)
+		die("Cannot mmap %s: %s", argv[1], strerror(errno));
+
+	close(fd);
+
+	unsigned char *e_ident = (unsigned char *)data;
+
+	if (memcmp(e_ident, ELFMAG, SELFMAG) != 0)
+		die("Invalid ELF file %s", argv[1]);
+
+	bool is64 = e_ident[EI_CLASS] == ELFCLASS64;
+
+	if (is64)
+		prelink64(data);
+	else
+		prelink32(data);
+
+	return 0;
+}