1/*
2 * include/asm-xtensa/ptrace.h
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License.  See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 2001 - 2005 Tensilica Inc.
9 */
10
11#ifndef _XTENSA_PTRACE_H
12#define _XTENSA_PTRACE_H
13
14/*
15 * Kernel stack
16 *
17 * 		+-----------------------+  -------- STACK_SIZE
18 * 		|     register file     |  |
19 * 		+-----------------------+  |
20 * 		|    struct pt_regs     |  |
21 * 		+-----------------------+  | ------ PT_REGS_OFFSET
22 * double 	:  16 bytes spill area  :  |  ^
23 * excetion 	:- - - - - - - - - - - -:  |  |
24 * frame	:    struct pt_regs     :  |  |
25 * 		:- - - - - - - - - - - -:  |  |
26 * 		|                       |  |  |
27 * 		|     memory stack      |  |  |
28 * 		|                       |  |  |
29 * 		~                       ~  ~  ~
30 * 		~                       ~  ~  ~
31 * 		|                       |  |  |
32 * 		|                       |  |  |
33 * 		+-----------------------+  |  | --- STACK_BIAS
34 * 		|  struct task_struct   |  |  |  ^
35 *  current --> +-----------------------+  |  |  |
36 * 		|  struct thread_info   |  |  |  |
37 *		+-----------------------+ --------
38 */
39
40#define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
41
42/*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables). */
43
44#define EXC_TABLE_KSTK		0x004	/* Kernel Stack */
45#define EXC_TABLE_DOUBLE_SAVE	0x008	/* Double exception save area for a0 */
46#define EXC_TABLE_FIXUP		0x00c	/* Fixup handler */
47#define EXC_TABLE_PARAM		0x010	/* For passing a parameter to fixup */
48#define EXC_TABLE_SYSCALL_SAVE	0x014	/* For fast syscall handler */
49#define EXC_TABLE_FAST_USER	0x100	/* Fast user exception handler */
50#define EXC_TABLE_FAST_KERNEL	0x200	/* Fast kernel exception handler */
51#define EXC_TABLE_DEFAULT	0x300	/* Default C-Handler */
52#define EXC_TABLE_SIZE		0x400
53
54/* Registers used by strace */
55
56#define REG_A_BASE	0x0000
57#define REG_AR_BASE	0x0100
58#define REG_PC		0x0020
59#define REG_PS		0x02e6
60#define REG_WB		0x0248
61#define REG_WS		0x0249
62#define REG_LBEG	0x0200
63#define REG_LEND	0x0201
64#define REG_LCOUNT	0x0202
65#define REG_SAR		0x0203
66
67#define SYSCALL_NR	0x00ff
68
69/* Other PTRACE_ values defined in <linux/ptrace.h> using values 0-9,16,17,24 */
70
71#define PTRACE_GETREGS		12
72#define PTRACE_SETREGS		13
73#define PTRACE_GETXTREGS	18
74#define PTRACE_SETXTREGS	19
75
76#ifdef __KERNEL__
77
78#ifndef __ASSEMBLY__
79
80#include <asm/coprocessor.h>
81
82/*
83 * This struct defines the way the registers are stored on the
84 * kernel stack during a system call or other kernel entry.
85 */
86struct pt_regs {
87	unsigned long pc;		/*   4 */
88	unsigned long ps;		/*   8 */
89	unsigned long depc;		/*  12 */
90	unsigned long exccause;		/*  16 */
91	unsigned long excvaddr;		/*  20 */
92	unsigned long debugcause;	/*  24 */
93	unsigned long wmask;		/*  28 */
94	unsigned long lbeg;		/*  32 */
95	unsigned long lend;		/*  36 */
96	unsigned long lcount;		/*  40 */
97	unsigned long sar;		/*  44 */
98	unsigned long windowbase;	/*  48 */
99	unsigned long windowstart;	/*  52 */
100	unsigned long syscall;		/*  56 */
101	unsigned long icountlevel;	/*  60 */
102	int reserved[1];		/*  64 */
103
104	/* Additional configurable registers that are used by the compiler. */
105	xtregs_opt_t xtregs_opt;
106
107	/* Make sure the areg field is 16 bytes aligned. */
108	int align[0] __attribute__ ((aligned(16)));
109
110	/* current register frame.
111	 * Note: The ESF for kernel exceptions ends after 16 registers!
112	 */
113	unsigned long areg[16];		/* 128 (64) */
114};
115
116#include <variant/core.h>
117
118# define arch_has_single_step()	(1)
119# define task_pt_regs(tsk) ((struct pt_regs*) \
120  (task_stack_page(tsk) + KERNEL_STACK_SIZE - (XCHAL_NUM_AREGS-16)*4) - 1)
121# define user_mode(regs) (((regs)->ps & 0x00000020)!=0)
122# define instruction_pointer(regs) ((regs)->pc)
123
124# ifndef CONFIG_SMP
125#  define profile_pc(regs) instruction_pointer(regs)
126# endif
127
128#else	/* __ASSEMBLY__ */
129
130# include <asm/asm-offsets.h>
131#define PT_REGS_OFFSET	  (KERNEL_STACK_SIZE - PT_USER_SIZE)
132
133#endif	/* !__ASSEMBLY__ */
134
135#endif  /* __KERNEL__ */
136
137#endif	/* _XTENSA_PTRACE_H */
138