1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Mapping of DWARF debug register numbers into register names.
4 *
5 * Copyright (C) 2010 Will Deacon, ARM Ltd.
6 */
7
8#include <stddef.h>
9#include <linux/stringify.h>
10#include <dwarf-regs.h>
11
12struct pt_regs_dwarfnum {
13	const char *name;
14	unsigned int dwarfnum;
15};
16
17#define REG_DWARFNUM_NAME(r, num) {.name = r, .dwarfnum = num}
18#define GPR_DWARFNUM_NAME(num) \
19	{.name = __stringify(%r##num), .dwarfnum = num}
20#define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0}
21
22/*
23 * Reference:
24 * http://infocenter.arm.com/help/topic/com.arm.doc.ihi0040a/IHI0040A_aadwarf.pdf
25 */
26static const struct pt_regs_dwarfnum regdwarfnum_table[] = {
27	GPR_DWARFNUM_NAME(0),
28	GPR_DWARFNUM_NAME(1),
29	GPR_DWARFNUM_NAME(2),
30	GPR_DWARFNUM_NAME(3),
31	GPR_DWARFNUM_NAME(4),
32	GPR_DWARFNUM_NAME(5),
33	GPR_DWARFNUM_NAME(6),
34	GPR_DWARFNUM_NAME(7),
35	GPR_DWARFNUM_NAME(8),
36	GPR_DWARFNUM_NAME(9),
37	GPR_DWARFNUM_NAME(10),
38	REG_DWARFNUM_NAME("%fp", 11),
39	REG_DWARFNUM_NAME("%ip", 12),
40	REG_DWARFNUM_NAME("%sp", 13),
41	REG_DWARFNUM_NAME("%lr", 14),
42	REG_DWARFNUM_NAME("%pc", 15),
43	REG_DWARFNUM_END,
44};
45
46/**
47 * get_arch_regstr() - lookup register name from it's DWARF register number
48 * @n:	the DWARF register number
49 *
50 * get_arch_regstr() returns the name of the register in struct
51 * regdwarfnum_table from it's DWARF register number. If the register is not
52 * found in the table, this returns NULL;
53 */
54const char *get_arch_regstr(unsigned int n)
55{
56	const struct pt_regs_dwarfnum *roff;
57	for (roff = regdwarfnum_table; roff->name != NULL; roff++)
58		if (roff->dwarfnum == n)
59			return roff->name;
60	return NULL;
61}
62