[U-Boot] [PATCH v2 09/12] riscv: tools: Prelink u-boot
Andes
uboot at andestech.com
Tue Dec 26 05:55:56 UTC 2017
From: Rick Chen <rick at andestech.com>
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 at andestech.com>
Signed-off-by: Rick Chen <rick at andestech.com>
Signed-off-by: Rick Chen <rickchen36 at gmail.com>
Signed-off-by: Greentime Hu <green.hu at gmail.com>
---
Makefile | 4 ++
tools/Makefile | 1 +
tools/prelink-riscv.c | 102 +++++++++++++++++++++++++++++++++++++++++++
tools/prelink-riscv.inc | 112 ++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 219 insertions(+)
create mode 100644 tools/prelink-riscv.c
create mode 100644 tools/prelink-riscv.inc
diff --git a/Makefile b/Makefile
index c573ddb..bb6416f 100644
--- a/Makefile
+++ b/Makefile
@@ -1264,6 +1264,10 @@ ifeq ($(CONFIG_KALLSYMS),y)
$(call cmd,u-boot__) common/system_map.o
endif
+ifeq ($(CONFIG_RISCV),y)
+ @tools/prelink-riscv $@ 0
+endif
+
quiet_cmd_sym ?= SYM $@
cmd_sym ?= $(OBJDUMP) -t $< > $@
u-boot.sym: u-boot FORCE
diff --git a/tools/Makefile b/tools/Makefile
index 4d32fe5..571f571 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -185,6 +185,7 @@ hostprogs-$(CONFIG_KIRKWOOD) += kwboot
hostprogs-$(CONFIG_ARCH_MVEBU) += kwboot
hostprogs-y += proftool
hostprogs-$(CONFIG_STATIC_RELA) += relocate-rela
+hostprogs-$(CONFIG_RISCV) += prelink-riscv
hostprogs-y += fdtgrep
fdtgrep-objs += $(LIBFDT_OBJS) fdtgrep.o
diff --git a/tools/prelink-riscv.c b/tools/prelink-riscv.c
new file mode 100644
index 0000000..632d2da
--- /dev/null
+++ b/tools/prelink-riscv.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2017 Andes Technology
+ * Chih-Mao Chen <cmchen at 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;
+}
diff --git a/tools/prelink-riscv.inc b/tools/prelink-riscv.inc
new file mode 100644
index 0000000..c07d930
--- /dev/null
+++ b/tools/prelink-riscv.inc
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2017 Andes Technology
+ * Chih-Mao Chen <cmchen at 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.
+ */
+
+#define CONCAT_IMPL(x, y) x##y
+#define CONCAT(x, y) CONCAT_IMPL(x, y)
+#define CONCAT3(x, y, z) CONCAT(CONCAT(x, y), z)
+
+#define prelink_nn CONCAT(prelink, PRELINK_INC_BITS)
+#define uintnn_t CONCAT3(uint, PRELINK_INC_BITS, _t)
+#define get_offset_nn CONCAT(get_offset_, PRELINK_INC_BITS)
+#define Elf_Ehdr CONCAT3(Elf, PRELINK_INC_BITS, _Ehdr)
+#define Elf_Phdr CONCAT3(Elf, PRELINK_INC_BITS, _Phdr)
+#define Elf_Rela CONCAT3(Elf, PRELINK_INC_BITS, _Rela)
+#define Elf_Sym CONCAT3(Elf, PRELINK_INC_BITS, _Sym)
+#define Elf_Dyn CONCAT3(Elf, PRELINK_INC_BITS, _Dyn)
+#define Elf_Addr CONCAT3(Elf, PRELINK_INC_BITS, _Addr)
+#define ELF_R_TYPE CONCAT3(ELF, PRELINK_INC_BITS, _R_TYPE)
+#define ELF_R_SYM CONCAT3(ELF, PRELINK_INC_BITS, _R_SYM)
+
+static void* get_offset_nn (void* data, Elf_Phdr* phdrs, size_t phnum, Elf_Addr addr)
+{
+ Elf_Phdr *p;
+
+ for (p = phdrs; p < phdrs + phnum; ++p)
+ if (p->p_vaddr <= addr && p->p_vaddr + p->p_memsz > addr)
+ return data + p->p_offset + (addr - p->p_vaddr);
+
+ return NULL;
+}
+
+static void prelink_nn(void *data)
+{
+ Elf_Ehdr *ehdr = data;
+ Elf_Phdr *p;
+ Elf_Dyn *dyn;
+ Elf_Rela *r;
+
+ if (ehdr->e_machine != EM_RISCV)
+ die("Machine type is not RISC-V");
+
+ Elf_Phdr *phdrs = data + ehdr->e_phoff;
+
+ Elf_Dyn *dyns = NULL;
+ for (p = phdrs; p < phdrs + ehdr->e_phnum; ++p) {
+ if (p->p_type == PT_DYNAMIC) {
+ dyns = data + p->p_offset;
+ break;
+ }
+ }
+
+ if (dyns == NULL)
+ die("No dynamic section found");
+
+ Elf_Rela *rela_dyn = NULL;
+ size_t rela_count = 0;
+ Elf_Sym *dynsym = NULL;
+ for (dyn = dyns;; ++dyn) {
+ if (dyn->d_tag == DT_NULL)
+ break;
+ else if (dyn->d_tag == DT_RELA)
+ rela_dyn = get_offset_nn(data, phdrs, ehdr->e_phnum, + dyn->d_un.d_ptr);
+ else if (dyn->d_tag == DT_RELASZ)
+ rela_count = dyn->d_un.d_val / sizeof(Elf_Rela);
+ else if (dyn->d_tag == DT_SYMTAB)
+ dynsym = get_offset_nn(data, phdrs, ehdr->e_phnum, + dyn->d_un.d_ptr);
+
+ }
+
+ if (rela_dyn == NULL)
+ die("No .rela.dyn found");
+
+ if (dynsym == NULL)
+ die("No .dynsym found");
+
+ for (r = rela_dyn; r < rela_dyn + rela_count; ++r) {
+ void* buf = get_offset_nn(data, phdrs, ehdr->e_phnum, r->r_offset);
+
+ if (buf == NULL)
+ continue;
+
+ if (ELF_R_TYPE(r->r_info) == R_RISCV_RELATIVE)
+ *((uintnn_t*) buf) = r->r_addend;
+ else if (ELF_R_TYPE(r->r_info) == R_RISCV_32)
+ *((uint32_t*) buf) = dynsym[ELF_R_SYM(r->r_info)].st_value;
+ else if (ELF_R_TYPE(r->r_info) == R_RISCV_64)
+ *((uint64_t*) buf) = dynsym[ELF_R_SYM(r->r_info)].st_value;
+ }
+}
+
+#undef prelink_nn
+#undef uintnn_t
+#undef get_offset_nn
+#undef Elf_Ehdr
+#undef Elf_Phdr
+#undef Elf_Rela
+#undef Elf_Sym
+#undef Elf_Dyn
+#undef Elf_Addr
+#undef ELF_R_TYPE
+#undef ELF_R_SYM
+
+#undef CONCAT_IMPL
+#undef CONCAT
+#undef CONCAT3
--
2.7.4
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