1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * OpenRISC Linux
4 *
5 * Linux architectural port borrowing liberally from similar works of
6 * others.  All original copyrights apply as per the original source
7 * declaration.
8 *
9 * OpenRISC implementation:
10 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
12 * et al.
13 */
14#ifndef __ASM_OPENRISC_PTRACE_H
15#define __ASM_OPENRISC_PTRACE_H
16
17
18#include <asm/spr_defs.h>
19#include <uapi/asm/ptrace.h>
20
21/*
22 * Make kernel PTrace/register structures opaque to userspace... userspace can
23 * access thread state via the regset mechanism.  This allows us a bit of
24 * flexibility in how we order the registers on the stack, permitting some
25 * optimizations like packing call-clobbered registers together so that
26 * they share a cacheline (not done yet, though... future optimization).
27 */
28
29#ifndef __ASSEMBLY__
30/*
31 * This struct describes how the registers are laid out on the kernel stack
32 * during a syscall or other kernel entry.
33 *
34 * This structure should always be cacheline aligned on the stack.
35 * FIXME: I don't think that's the case right now.  The alignment is
36 * taken care of elsewhere... head.S, process.c, etc.
37 */
38
39struct pt_regs {
40	union {
41		struct {
42			/* Named registers */
43			long  sr;	/* Stored in place of r0 */
44			long  sp;	/* r1 */
45		};
46		struct {
47			/* Old style */
48			long offset[2];
49			long gprs[30];
50		};
51		struct {
52			/* New style */
53			long gpr[32];
54		};
55	};
56	long  pc;
57	/* For restarting system calls:
58	 * Set to syscall number for syscall exceptions,
59	 * -1 for all other exceptions.
60	 */
61	long  orig_gpr11;	/* For restarting system calls */
62	long fpcsr;		/* Floating point control status register. */
63	long dummy2;		/* Cheap alignment fix */
64};
65
66/* TODO: Rename this to REDZONE because that's what it is */
67#define STACK_FRAME_OVERHEAD  128  /* size of minimum stack frame */
68
69#define instruction_pointer(regs)	((regs)->pc)
70#define user_mode(regs)			(((regs)->sr & SPR_SR_SM) == 0)
71#define user_stack_pointer(regs)	((unsigned long)(regs)->sp)
72#define profile_pc(regs)		instruction_pointer(regs)
73
74static inline long regs_return_value(struct pt_regs *regs)
75{
76	return regs->gpr[11];
77}
78
79#endif /* __ASSEMBLY__ */
80
81/*
82 * Offsets used by 'ptrace' system call interface.
83 */
84#define PT_SR         0
85#define PT_SP         4
86#define PT_GPR2       8
87#define PT_GPR3       12
88#define PT_GPR4       16
89#define PT_GPR5       20
90#define PT_GPR6       24
91#define PT_GPR7       28
92#define PT_GPR8       32
93#define PT_GPR9       36
94#define PT_GPR10      40
95#define PT_GPR11      44
96#define PT_GPR12      48
97#define PT_GPR13      52
98#define PT_GPR14      56
99#define PT_GPR15      60
100#define PT_GPR16      64
101#define PT_GPR17      68
102#define PT_GPR18      72
103#define PT_GPR19      76
104#define PT_GPR20      80
105#define PT_GPR21      84
106#define PT_GPR22      88
107#define PT_GPR23      92
108#define PT_GPR24      96
109#define PT_GPR25      100
110#define PT_GPR26      104
111#define PT_GPR27      108
112#define PT_GPR28      112
113#define PT_GPR29      116
114#define PT_GPR30      120
115#define PT_GPR31      124
116#define PT_PC	      128
117#define PT_ORIG_GPR11 132
118#define PT_FPCSR      136
119
120#endif /* __ASM_OPENRISC_PTRACE_H */
121