1/* SPDX-License-Identifier: GPL-2.0 */
 2/*
 3 * Copyright (C) 2023 Loongson Technology Corporation Limited
 4 */
 5
 6#ifndef _ASM_LOONGARCH_KGDB_H
 7#define _ASM_LOONGARCH_KGDB_H
 8
 9#define GDB_SIZEOF_REG		sizeof(u64)
10
11/* gdb remote procotol expects the following register layout. */
12
13/*
14 * General purpose registers:
15 *     r0-r31: 64 bit
16 *     orig_a0: 64 bit
17 *     pc : 64 bit
18 *     csr_badvaddr: 64 bit
19 */
20#define DBG_PT_REGS_BASE	0
21#define DBG_PT_REGS_NUM		35
22#define DBG_PT_REGS_END		(DBG_PT_REGS_BASE + DBG_PT_REGS_NUM - 1)
23
24/*
25 * Floating point registers:
26 *     f0-f31: 64 bit
27 */
28#define DBG_FPR_BASE		(DBG_PT_REGS_END + 1)
29#define DBG_FPR_NUM		32
30#define DBG_FPR_END		(DBG_FPR_BASE + DBG_FPR_NUM - 1)
31
32/*
33 * Condition Flag registers:
34 *     fcc0-fcc8: 8 bit
35 */
36#define DBG_FCC_BASE		(DBG_FPR_END + 1)
37#define DBG_FCC_NUM		8
38#define DBG_FCC_END		(DBG_FCC_BASE + DBG_FCC_NUM - 1)
39
40/*
41 * Floating-point Control and Status registers:
42 *     fcsr: 32 bit
43 */
44#define DBG_FCSR_NUM		1
45#define DBG_FCSR		(DBG_FCC_END + 1)
46
47#define DBG_MAX_REG_NUM		(DBG_FCSR + 1)
48
49/*
50 * Size of I/O buffer for gdb packet.
51 * considering to hold all register contents, size is set
52 */
53#define BUFMAX			2048
54
55/*
56 * Number of bytes required for gdb_regs buffer.
57 * PT_REGS and FPR: 8 bytes; FCSR: 4 bytes; FCC: 1 bytes.
58 * GDB fails to connect for size beyond this with error
59 * "'g' packet reply is too long"
60 */
61#define NUMREGBYTES		((DBG_PT_REGS_NUM + DBG_FPR_NUM) * GDB_SIZEOF_REG + DBG_FCC_NUM * 1 + DBG_FCSR_NUM * 4)
62
63#define BREAK_INSTR_SIZE	4
64#define CACHE_FLUSH_IS_SAFE	0
65
66/* Register numbers of various important registers. */
67enum dbg_loongarch_regnum {
68	DBG_LOONGARCH_ZERO = 0,
69	DBG_LOONGARCH_RA,
70	DBG_LOONGARCH_TP,
71	DBG_LOONGARCH_SP,
72	DBG_LOONGARCH_A0,
73	DBG_LOONGARCH_FP = 22,
74	DBG_LOONGARCH_S0,
75	DBG_LOONGARCH_S1,
76	DBG_LOONGARCH_S2,
77	DBG_LOONGARCH_S3,
78	DBG_LOONGARCH_S4,
79	DBG_LOONGARCH_S5,
80	DBG_LOONGARCH_S6,
81	DBG_LOONGARCH_S7,
82	DBG_LOONGARCH_S8,
83	DBG_LOONGARCH_ORIG_A0,
84	DBG_LOONGARCH_PC,
85	DBG_LOONGARCH_BADV
86};
87
88void kgdb_breakinst(void);
89void arch_kgdb_breakpoint(void);
90
91#ifdef CONFIG_KGDB
92bool kgdb_breakpoint_handler(struct pt_regs *regs);
93#else /* !CONFIG_KGDB */
94static inline bool kgdb_breakpoint_handler(struct pt_regs *regs) { return false; }
95#endif /* CONFIG_KGDB */
96
97#endif /* __ASM_KGDB_H_ */