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 #ifndef _XTENSA_PTRACE_H
11 #define _XTENSA_PTRACE_H
12 
13 #include <asm/kmem_layout.h>
14 #include <uapi/asm/ptrace.h>
15 
16 /*
17  * Kernel stack
18  *
19  *		+-----------------------+  -------- STACK_SIZE
20  *		|     register file     |  |
21  *		+-----------------------+  |
22  *		|    struct pt_regs     |  |
23  *		+-----------------------+  | ------ PT_REGS_OFFSET
24  * double	:  16 bytes spill area  :  |  ^
25  * excetion	:- - - - - - - - - - - -:  |  |
26  * frame	:    struct pt_regs     :  |  |
27  *		:- - - - - - - - - - - -:  |  |
28  *		|                       |  |  |
29  *		|     memory stack      |  |  |
30  *		|                       |  |  |
31  *		~                       ~  ~  ~
32  *		~                       ~  ~  ~
33  *		|                       |  |  |
34  *		|                       |  |  |
35  *		+-----------------------+  |  | --- STACK_BIAS
36  *		|  struct task_struct   |  |  |  ^
37  *  current --> +-----------------------+  |  |  |
38  *		|  struct thread_info   |  |  |  |
39  *		+-----------------------+ --------
40  */
41 
42 #define NO_SYSCALL (-1)
43 
44 #ifndef __ASSEMBLY__
45 
46 #include <asm/coprocessor.h>
47 
48 /*
49  * This struct defines the way the registers are stored on the
50  * kernel stack during a system call or other kernel entry.
51  */
52 struct pt_regs {
53 	unsigned long pc;		/*   4 */
54 	unsigned long ps;		/*   8 */
55 	unsigned long depc;		/*  12 */
56 	unsigned long exccause;		/*  16 */
57 	unsigned long excvaddr;		/*  20 */
58 	unsigned long debugcause;	/*  24 */
59 	unsigned long wmask;		/*  28 */
60 	unsigned long lbeg;		/*  32 */
61 	unsigned long lend;		/*  36 */
62 	unsigned long lcount;		/*  40 */
63 	unsigned long sar;		/*  44 */
64 	unsigned long windowbase;	/*  48 */
65 	unsigned long windowstart;	/*  52 */
66 	unsigned long syscall;		/*  56 */
67 	unsigned long icountlevel;	/*  60 */
68 	unsigned long scompare1;	/*  64 */
69 	unsigned long threadptr;	/*  68 */
70 
71 	/* Additional configurable registers that are used by the compiler. */
72 	xtregs_opt_t xtregs_opt;
73 
74 	/* Make sure the areg field is 16 bytes aligned. */
75 	int align[0] __attribute__ ((aligned(16)));
76 
77 	/* current register frame.
78 	 * Note: The ESF for kernel exceptions ends after 16 registers!
79 	 */
80 	unsigned long areg[16];
81 };
82 
83 #include <asm/core.h>
84 
85 # define arch_has_single_step()	(1)
86 # define task_pt_regs(tsk) ((struct pt_regs*) \
87 	(task_stack_page(tsk) + KERNEL_STACK_SIZE - (XCHAL_NUM_AREGS-16)*4) - 1)
88 # define user_mode(regs) (((regs)->ps & 0x00000020)!=0)
89 # define instruction_pointer(regs) ((regs)->pc)
90 # define return_pointer(regs) (MAKE_PC_FROM_RA((regs)->areg[0], \
91 					       (regs)->areg[1]))
92 
93 # ifndef CONFIG_SMP
94 #  define profile_pc(regs) instruction_pointer(regs)
95 # else
96 #  define profile_pc(regs)						\
97 	({								\
98 		in_lock_functions(instruction_pointer(regs)) ?		\
99 		return_pointer(regs) : instruction_pointer(regs);	\
100 	})
101 # endif
102 
103 #define user_stack_pointer(regs) ((regs)->areg[1])
104 
regs_return_value(struct pt_regs * regs)105 static inline unsigned long regs_return_value(struct pt_regs *regs)
106 {
107 	return regs->areg[2];
108 }
109 
110 #else	/* __ASSEMBLY__ */
111 
112 # include <asm/asm-offsets.h>
113 #define PT_REGS_OFFSET	  (KERNEL_STACK_SIZE - PT_USER_SIZE)
114 
115 #endif	/* !__ASSEMBLY__ */
116 
117 #endif	/* _XTENSA_PTRACE_H */
118