[PATCH v1 1/6] objtool/LoongArch: Enable objtool to be built
From: Tiezhu Yang
Date: Tue Jul 25 2023 - 04:15:29 EST
Add the minimal changes to enable objtool build on LoongArch,
most of the functions are stubs to only fix the build errors
when make -C tools/objtool.
This is similar with commit e52ec98c5ab1 ("objtool/powerpc:
Enable objtool to be built on ppc").
Co-developed-by: Jinyang He <hejinyang@xxxxxxxxxxx>
Signed-off-by: Jinyang He <hejinyang@xxxxxxxxxxx>
Co-developed-by: Youling Tang <tangyouling@xxxxxxxxxxx>
Signed-off-by: Youling Tang <tangyouling@xxxxxxxxxxx>
Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
tools/objtool/arch/loongarch/Build | 2 +
tools/objtool/arch/loongarch/decode.c | 71 ++++++++++++++++++++++
.../objtool/arch/loongarch/include/arch/cfi_regs.h | 21 +++++++
tools/objtool/arch/loongarch/include/arch/elf.h | 30 +++++++++
.../objtool/arch/loongarch/include/arch/special.h | 33 ++++++++++
tools/objtool/arch/loongarch/special.c | 15 +++++
6 files changed, 172 insertions(+)
create mode 100644 tools/objtool/arch/loongarch/Build
create mode 100644 tools/objtool/arch/loongarch/decode.c
create mode 100644 tools/objtool/arch/loongarch/include/arch/cfi_regs.h
create mode 100644 tools/objtool/arch/loongarch/include/arch/elf.h
create mode 100644 tools/objtool/arch/loongarch/include/arch/special.h
create mode 100644 tools/objtool/arch/loongarch/special.c
diff --git a/tools/objtool/arch/loongarch/Build b/tools/objtool/arch/loongarch/Build
new file mode 100644
index 0000000..d24d563
--- /dev/null
+++ b/tools/objtool/arch/loongarch/Build
@@ -0,0 +1,2 @@
+objtool-y += decode.o
+objtool-y += special.o
diff --git a/tools/objtool/arch/loongarch/decode.c b/tools/objtool/arch/loongarch/decode.c
new file mode 100644
index 0000000..cc74ba4
--- /dev/null
+++ b/tools/objtool/arch/loongarch/decode.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <string.h>
+#include <objtool/check.h>
+
+int arch_ftrace_match(char *name)
+{
+ return !strcmp(name, "_mcount");
+}
+
+unsigned long arch_jump_destination(struct instruction *insn)
+{
+ return insn->offset + (insn->immediate << 2);
+}
+
+unsigned long arch_dest_reloc_offset(int addend)
+{
+ return addend;
+}
+
+bool arch_pc_relative_reloc(struct reloc *reloc)
+{
+ return false;
+}
+
+bool arch_callee_saved_reg(unsigned char reg)
+{
+ switch (reg) {
+ case CFI_RA:
+ case CFI_FP:
+ case CFI_S0 ... CFI_S8:
+ return true;
+ default:
+ return false;
+ }
+}
+
+int arch_decode_hint_reg(u8 sp_reg, int *base)
+{
+ return 0;
+}
+
+int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
+ unsigned long offset, unsigned int maxlen,
+ struct instruction *insn)
+{
+ return 0;
+}
+
+const char *arch_nop_insn(int len)
+{
+ return NULL;
+}
+
+const char *arch_ret_insn(int len)
+{
+ return NULL;
+}
+
+void arch_initial_func_cfi_state(struct cfi_init_state *state)
+{
+ int i;
+
+ for (i = 0; i < CFI_NUM_REGS; i++) {
+ state->regs[i].base = CFI_UNDEFINED;
+ state->regs[i].offset = 0;
+ }
+
+ /* initial CFA (call frame address) */
+ state->cfa.base = CFI_SP;
+ state->cfa.offset = 0;
+}
diff --git a/tools/objtool/arch/loongarch/include/arch/cfi_regs.h b/tools/objtool/arch/loongarch/include/arch/cfi_regs.h
new file mode 100644
index 0000000..c768d39
--- /dev/null
+++ b/tools/objtool/arch/loongarch/include/arch/cfi_regs.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_CFI_REGS_H
+#define _OBJTOOL_ARCH_CFI_REGS_H
+
+#define CFI_RA 1
+#define CFI_SP 3
+#define CFI_FP 22
+#define CFI_S0 23
+#define CFI_S1 24
+#define CFI_S2 25
+#define CFI_S3 26
+#define CFI_S4 27
+#define CFI_S5 28
+#define CFI_S6 29
+#define CFI_S7 30
+#define CFI_S8 31
+#define CFI_NUM_REGS 32
+
+#define CFI_BP CFI_FP
+
+#endif /* _OBJTOOL_ARCH_CFI_REGS_H */
diff --git a/tools/objtool/arch/loongarch/include/arch/elf.h b/tools/objtool/arch/loongarch/include/arch/elf.h
new file mode 100644
index 0000000..9623d66
--- /dev/null
+++ b/tools/objtool/arch/loongarch/include/arch/elf.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_ELF_H
+#define _OBJTOOL_ARCH_ELF_H
+
+/*
+ * See the following link for more info about ELF Relocation types:
+ * https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html#_relocations
+ */
+#ifndef R_LARCH_NONE
+#define R_LARCH_NONE 0
+#endif
+#ifndef R_LARCH_32
+#define R_LARCH_32 1
+#endif
+#ifndef R_LARCH_64
+#define R_LARCH_64 2
+#endif
+#ifndef R_LARCH_32_PCREL
+#define R_LARCH_32_PCREL 99
+#endif
+
+#define R_NONE R_LARCH_NONE
+#define R_ABS32 R_LARCH_32
+#define R_ABS64 R_LARCH_64
+#define R_DATA32 R_LARCH_32_PCREL
+#define R_DATA64 R_LARCH_32_PCREL
+#define R_TEXT32 R_LARCH_32_PCREL
+#define R_TEXT64 R_LARCH_32_PCREL
+
+#endif /* _OBJTOOL_ARCH_ELF_H */
diff --git a/tools/objtool/arch/loongarch/include/arch/special.h b/tools/objtool/arch/loongarch/include/arch/special.h
new file mode 100644
index 0000000..1a8245c
--- /dev/null
+++ b/tools/objtool/arch/loongarch/include/arch/special.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_SPECIAL_H
+#define _OBJTOOL_ARCH_SPECIAL_H
+
+/*
+ * See more info about struct exception_table_entry
+ * in arch/loongarch/include/asm/extable.h
+ */
+#define EX_ENTRY_SIZE 12
+#define EX_ORIG_OFFSET 0
+#define EX_NEW_OFFSET 4
+
+/*
+ * See more info about struct jump_entry
+ * in include/linux/jump_label.h
+ */
+#define JUMP_ENTRY_SIZE 16
+#define JUMP_ORIG_OFFSET 0
+#define JUMP_NEW_OFFSET 4
+#define JUMP_KEY_OFFSET 8
+
+/*
+ * See more info about struct alt_instr
+ * in arch/loongarch/include/asm/alternative.h
+ */
+#define ALT_ENTRY_SIZE 12
+#define ALT_ORIG_OFFSET 0
+#define ALT_NEW_OFFSET 4
+#define ALT_FEATURE_OFFSET 8
+#define ALT_ORIG_LEN_OFFSET 10
+#define ALT_NEW_LEN_OFFSET 11
+
+#endif /* _OBJTOOL_ARCH_SPECIAL_H */
diff --git a/tools/objtool/arch/loongarch/special.c b/tools/objtool/arch/loongarch/special.c
new file mode 100644
index 0000000..9bba1e9
--- /dev/null
+++ b/tools/objtool/arch/loongarch/special.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <objtool/special.h>
+
+bool arch_support_alt_relocation(struct special_alt *special_alt,
+ struct instruction *insn,
+ struct reloc *reloc)
+{
+ return false;
+}
+
+struct reloc *arch_find_switch_table(struct objtool_file *file,
+ struct instruction *insn)
+{
+ return NULL;
+}
--
2.1.0