xref: /openbmc/u-boot/arch/xtensa/include/asm/ptrace.h (revision d5abcf94)
1 /*
2  * Copyright (C) 2001 - 2007 Tensilica Inc.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #ifndef _XTENSA_PTRACE_H
8 #define _XTENSA_PTRACE_H
9 
10 #include <compiler.h>
11 
12 /*
13  * Kernel stack
14  *
15  *		+-----------------------+  -------- STACK_SIZE
16  *		|     register file     |  |
17  *		+-----------------------+  |
18  *		|    struct pt_regs     |  |
19  *		+-----------------------+  | ------ PT_REGS_OFFSET
20  * double	:  16 bytes spill area  :  |  ^
21  * exception	:- - - - - - - - - - - -:  |  |
22  * frame	:    struct pt_regs     :  |  |
23  *		:- - - - - - - - - - - -:  |  |
24  *		|                       |  |  |
25  *		|     memory stack      |  |  |
26  *		|                       |  |  |
27  *		~                       ~  ~  ~
28  *		~                       ~  ~  ~
29  *		|                       |  |  |
30  *		|                       |  |  |
31  *		+-----------------------+  |  | --- STACK_BIAS
32  *		|  struct task_struct   |  |  |  ^
33  *  current --> +-----------------------+  |  |  |
34  *		|  struct thread_info   |  |  |  |
35  *		+-----------------------+ --------
36  */
37 
38 #define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
39 
40 /*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables) */
41 
42 #define EXC_TABLE_KSTK		0x004	/* Kernel Stack */
43 #define EXC_TABLE_DOUBLE_SAVE	0x008	/* Double exception save area for a0 */
44 #define EXC_TABLE_FIXUP		0x00c	/* Fixup handler */
45 #define EXC_TABLE_PARAM		0x010	/* For passing a parameter to fixup */
46 #define EXC_TABLE_SYSCALL_SAVE	0x014	/* For fast syscall handler */
47 #define EXC_TABLE_FAST_USER	0x100	/* Fast user exception handler */
48 #define EXC_TABLE_FAST_KERNEL	0x200	/* Fast kernel exception handler */
49 #define EXC_TABLE_DEFAULT	0x300	/* Default C-Handler */
50 #define EXC_TABLE_SIZE		0x400
51 
52 /* Registers used by strace */
53 
54 #define REG_A_BASE	0xfc000000
55 #define REG_AR_BASE	0x04000000
56 #define REG_PC		0x14000000
57 #define REG_PS		0x080000e6
58 #define REG_WB		0x08000048
59 #define REG_WS		0x08000049
60 #define REG_LBEG	0x08000000
61 #define REG_LEND	0x08000001
62 #define REG_LCOUNT	0x08000002
63 #define REG_SAR		0x08000003
64 #define REG_DEPC	0x080000c0
65 #define REG_EXCCAUSE	0x080000e8
66 #define REG_EXCVADDR	0x080000ee
67 #define SYSCALL_NR	0x1
68 
69 #define AR_REGNO_TO_A_REGNO(ar, wb) (ar - wb*4) & ~(XCHAL_NUM_AREGS - 1)
70 
71 /* Other PTRACE_ values defined in <linux/ptrace.h> using values 0-9,16,17,24 */
72 
73 #define PTRACE_GETREGS            12
74 #define PTRACE_SETREGS            13
75 #define PTRACE_GETFPREGS          14
76 #define PTRACE_SETFPREGS          15
77 #define PTRACE_GETFPREGSIZE       18
78 
79 #ifndef __ASSEMBLY__
80 
81 /*
82  * This struct defines the way the registers are stored on the
83  * kernel stack during a system call or other kernel entry.
84  */
85 struct pt_regs {
86 	unsigned long pc;		/*   4 */
87 	unsigned long ps;		/*   8 */
88 	unsigned long depc;		/*  12 */
89 	unsigned long exccause;		/*  16 */
90 	unsigned long excvaddr;		/*  20 */
91 	unsigned long debugcause;	/*  24 */
92 	unsigned long wmask;		/*  28 */
93 	unsigned long lbeg;		/*  32 */
94 	unsigned long lend;		/*  36 */
95 	unsigned long lcount;		/*  40 */
96 	unsigned long sar;		/*  44 */
97 	unsigned long windowbase;	/*  48 */
98 	unsigned long windowstart;	/*  52 */
99 	unsigned long syscall;		/*  56 */
100 	unsigned long icountlevel;	/*  60 */
101 	int reserved[1];		/*  64 */
102 
103 	/* Make sure the areg field is 16 bytes aligned */
104 	int align[0] __aligned(16);
105 
106 	/* current register frame.
107 	 * Note: The ESF for kernel exceptions ends after 16 registers!
108 	 */
109 	unsigned long areg[16];		/* 128 (64) */
110 };
111 
112 #ifdef __KERNEL__
113 
114 # define task_pt_regs(tsk) ((struct pt_regs *) \
115 	(task_stack_page(tsk) + KERNEL_STACK_SIZE - (XCHAL_NUM_AREGS-16)*4) - 1)
116 # define user_mode(regs) (((regs)->ps & 0x00000020) != 0)
117 # define instruction_pointer(regs) ((regs)->pc)
118 void show_regs(struct pt_regs *);
119 
120 # ifndef CONFIG_SMP
121 #  define profile_pc(regs) instruction_pointer(regs)
122 # endif
123 #endif /* __KERNEL__ */
124 
125 #else	/* __ASSEMBLY__ */
126 
127 #ifdef __KERNEL__
128 # include <asm/asm-offsets.h>
129 #define PT_REGS_OFFSET	  (KERNEL_STACK_SIZE - PT_USER_SIZE)
130 #endif
131 
132 #endif	/* !__ASSEMBLY__ */
133 #endif	/* _XTENSA_PTRACE_H */
134