1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Mapping of DWARF debug register numbers into register names.
4 *
5 * Copyright (C) 2010 Ian Munsie, IBM Corporation.
6 */
7
8#include <stddef.h>
9#include <errno.h>
10#include <string.h>
11#include <dwarf-regs.h>
12#include <linux/ptrace.h>
13#include <linux/kernel.h>
14#include <linux/stringify.h>
15
16struct pt_regs_dwarfnum {
17	const char *name;
18	unsigned int dwarfnum;
19	unsigned int ptregs_offset;
20};
21
22#define REG_DWARFNUM_NAME(r, num)					\
23		{.name = __stringify(%)__stringify(r), .dwarfnum = num,			\
24		.ptregs_offset = offsetof(struct pt_regs, r)}
25#define GPR_DWARFNUM_NAME(num)						\
26		{.name = __stringify(%gpr##num), .dwarfnum = num,		\
27		.ptregs_offset = offsetof(struct pt_regs, gpr[num])}
28#define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0, .ptregs_offset = 0}
29
30/*
31 * Reference:
32 * http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi-1.9.html
33 */
34static const struct pt_regs_dwarfnum regdwarfnum_table[] = {
35	GPR_DWARFNUM_NAME(0),
36	GPR_DWARFNUM_NAME(1),
37	GPR_DWARFNUM_NAME(2),
38	GPR_DWARFNUM_NAME(3),
39	GPR_DWARFNUM_NAME(4),
40	GPR_DWARFNUM_NAME(5),
41	GPR_DWARFNUM_NAME(6),
42	GPR_DWARFNUM_NAME(7),
43	GPR_DWARFNUM_NAME(8),
44	GPR_DWARFNUM_NAME(9),
45	GPR_DWARFNUM_NAME(10),
46	GPR_DWARFNUM_NAME(11),
47	GPR_DWARFNUM_NAME(12),
48	GPR_DWARFNUM_NAME(13),
49	GPR_DWARFNUM_NAME(14),
50	GPR_DWARFNUM_NAME(15),
51	GPR_DWARFNUM_NAME(16),
52	GPR_DWARFNUM_NAME(17),
53	GPR_DWARFNUM_NAME(18),
54	GPR_DWARFNUM_NAME(19),
55	GPR_DWARFNUM_NAME(20),
56	GPR_DWARFNUM_NAME(21),
57	GPR_DWARFNUM_NAME(22),
58	GPR_DWARFNUM_NAME(23),
59	GPR_DWARFNUM_NAME(24),
60	GPR_DWARFNUM_NAME(25),
61	GPR_DWARFNUM_NAME(26),
62	GPR_DWARFNUM_NAME(27),
63	GPR_DWARFNUM_NAME(28),
64	GPR_DWARFNUM_NAME(29),
65	GPR_DWARFNUM_NAME(30),
66	GPR_DWARFNUM_NAME(31),
67	REG_DWARFNUM_NAME(msr,   66),
68	REG_DWARFNUM_NAME(ctr,   109),
69	REG_DWARFNUM_NAME(link,  108),
70	REG_DWARFNUM_NAME(xer,   101),
71	REG_DWARFNUM_NAME(dar,   119),
72	REG_DWARFNUM_NAME(dsisr, 118),
73	REG_DWARFNUM_END,
74};
75
76/**
77 * get_arch_regstr() - lookup register name from it's DWARF register number
78 * @n:	the DWARF register number
79 *
80 * get_arch_regstr() returns the name of the register in struct
81 * regdwarfnum_table from it's DWARF register number. If the register is not
82 * found in the table, this returns NULL;
83 */
84const char *get_arch_regstr(unsigned int n)
85{
86	const struct pt_regs_dwarfnum *roff;
87	for (roff = regdwarfnum_table; roff->name != NULL; roff++)
88		if (roff->dwarfnum == n)
89			return roff->name;
90	return NULL;
91}
92
93int regs_query_register_offset(const char *name)
94{
95	const struct pt_regs_dwarfnum *roff;
96	for (roff = regdwarfnum_table; roff->name != NULL; roff++)
97		if (!strcmp(roff->name, name))
98			return roff->ptregs_offset;
99	return -EINVAL;
100}
101