xref: /openbmc/linux/arch/ia64/include/asm/unwind.h (revision 293d5b43)
1 #ifndef _ASM_IA64_UNWIND_H
2 #define _ASM_IA64_UNWIND_H
3 
4 /*
5  * Copyright (C) 1999-2000, 2003 Hewlett-Packard Co
6  *	David Mosberger-Tang <davidm@hpl.hp.com>
7  *
8  * A simple API for unwinding kernel stacks.  This is used for
9  * debugging and error reporting purposes.  The kernel doesn't need
10  * full-blown stack unwinding with all the bells and whitles, so there
11  * is not much point in implementing the full IA-64 unwind API (though
12  * it would of course be possible to implement the kernel API on top
13  * of it).
14  */
15 
16 struct task_struct;	/* forward declaration */
17 struct switch_stack;	/* forward declaration */
18 
19 enum unw_application_register {
20 	UNW_AR_BSP,
21 	UNW_AR_BSPSTORE,
22 	UNW_AR_PFS,
23 	UNW_AR_RNAT,
24 	UNW_AR_UNAT,
25 	UNW_AR_LC,
26 	UNW_AR_EC,
27 	UNW_AR_FPSR,
28 	UNW_AR_RSC,
29 	UNW_AR_CCV,
30 	UNW_AR_CSD,
31 	UNW_AR_SSD
32 };
33 
34 /*
35  * The following declarations are private to the unwind
36  * implementation:
37  */
38 
39 struct unw_stack {
40 	unsigned long limit;
41 	unsigned long top;
42 };
43 
44 #define UNW_FLAG_INTERRUPT_FRAME	(1UL << 0)
45 
46 /*
47  * No user of this module should every access this structure directly
48  * as it is subject to change.  It is declared here solely so we can
49  * use automatic variables.
50  */
51 struct unw_frame_info {
52 	struct unw_stack regstk;
53 	struct unw_stack memstk;
54 	unsigned int flags;
55 	short hint;
56 	short prev_script;
57 
58 	/* current frame info: */
59 	unsigned long bsp;		/* backing store pointer value */
60 	unsigned long sp;		/* stack pointer value */
61 	unsigned long psp;		/* previous sp value */
62 	unsigned long ip;		/* instruction pointer value */
63 	unsigned long pr;		/* current predicate values */
64 	unsigned long *cfm_loc;		/* cfm save location (or NULL) */
65 	unsigned long pt;		/* struct pt_regs location */
66 
67 	struct task_struct *task;
68 	struct switch_stack *sw;
69 
70 	/* preserved state: */
71 	unsigned long *bsp_loc;		/* previous bsp save location */
72 	unsigned long *bspstore_loc;
73 	unsigned long *pfs_loc;
74 	unsigned long *rnat_loc;
75 	unsigned long *rp_loc;
76 	unsigned long *pri_unat_loc;
77 	unsigned long *unat_loc;
78 	unsigned long *pr_loc;
79 	unsigned long *lc_loc;
80 	unsigned long *fpsr_loc;
81 	struct unw_ireg {
82 		unsigned long *loc;
83 		struct unw_ireg_nat {
84 			unsigned long type : 3;		/* enum unw_nat_type */
85 			signed long off : 61;		/* NaT word is at loc+nat.off */
86 		} nat;
87 	} r4, r5, r6, r7;
88 	unsigned long *b1_loc, *b2_loc, *b3_loc, *b4_loc, *b5_loc;
89 	struct ia64_fpreg *f2_loc, *f3_loc, *f4_loc, *f5_loc, *fr_loc[16];
90 };
91 
92 /*
93  * The official API follows below:
94  */
95 
96 struct unw_table_entry {
97 	u64 start_offset;
98 	u64 end_offset;
99 	u64 info_offset;
100 };
101 
102 /*
103  * Initialize unwind support.
104  */
105 extern void unw_init (void);
106 
107 extern void *unw_add_unwind_table (const char *name, unsigned long segment_base, unsigned long gp,
108 				   const void *table_start, const void *table_end);
109 
110 extern void unw_remove_unwind_table (void *handle);
111 
112 /*
113  * Prepare to unwind blocked task t.
114  */
115 extern void unw_init_from_blocked_task (struct unw_frame_info *info, struct task_struct *t);
116 
117 extern void unw_init_frame_info (struct unw_frame_info *info, struct task_struct *t,
118 				 struct switch_stack *sw);
119 
120 /*
121  * Prepare to unwind the currently running thread.
122  */
123 extern void unw_init_running (void (*callback)(struct unw_frame_info *info, void *arg), void *arg);
124 
125 /*
126  * Unwind to previous to frame.  Returns 0 if successful, negative
127  * number in case of an error.
128  */
129 extern int unw_unwind (struct unw_frame_info *info);
130 
131 /*
132  * Unwind until the return pointer is in user-land (or until an error
133  * occurs).  Returns 0 if successful, negative number in case of
134  * error.
135  */
136 extern int unw_unwind_to_user (struct unw_frame_info *info);
137 
138 #define unw_is_intr_frame(info)	(((info)->flags & UNW_FLAG_INTERRUPT_FRAME) != 0)
139 
140 static inline int
141 unw_get_ip (struct unw_frame_info *info, unsigned long *valp)
142 {
143 	*valp = (info)->ip;
144 	return 0;
145 }
146 
147 static inline int
148 unw_get_sp (struct unw_frame_info *info, unsigned long *valp)
149 {
150 	*valp = (info)->sp;
151 	return 0;
152 }
153 
154 static inline int
155 unw_get_psp (struct unw_frame_info *info, unsigned long *valp)
156 {
157 	*valp = (info)->psp;
158 	return 0;
159 }
160 
161 static inline int
162 unw_get_bsp (struct unw_frame_info *info, unsigned long *valp)
163 {
164 	*valp = (info)->bsp;
165 	return 0;
166 }
167 
168 static inline int
169 unw_get_cfm (struct unw_frame_info *info, unsigned long *valp)
170 {
171 	*valp = *(info)->cfm_loc;
172 	return 0;
173 }
174 
175 static inline int
176 unw_set_cfm (struct unw_frame_info *info, unsigned long val)
177 {
178 	*(info)->cfm_loc = val;
179 	return 0;
180 }
181 
182 static inline int
183 unw_get_rp (struct unw_frame_info *info, unsigned long *val)
184 {
185 	if (!info->rp_loc)
186 		return -1;
187 	*val = *info->rp_loc;
188 	return 0;
189 }
190 
191 extern int unw_access_gr (struct unw_frame_info *, int, unsigned long *, char *, int);
192 extern int unw_access_br (struct unw_frame_info *, int, unsigned long *, int);
193 extern int unw_access_fr (struct unw_frame_info *, int, struct ia64_fpreg *, int);
194 extern int unw_access_ar (struct unw_frame_info *, int, unsigned long *, int);
195 extern int unw_access_pr (struct unw_frame_info *, unsigned long *, int);
196 
197 static inline int
198 unw_set_gr (struct unw_frame_info *i, int n, unsigned long v, char nat)
199 {
200 	return unw_access_gr(i, n, &v, &nat, 1);
201 }
202 
203 static inline int
204 unw_set_br (struct unw_frame_info *i, int n, unsigned long v)
205 {
206 	return unw_access_br(i, n, &v, 1);
207 }
208 
209 static inline int
210 unw_set_fr (struct unw_frame_info *i, int n, struct ia64_fpreg v)
211 {
212 	return unw_access_fr(i, n, &v, 1);
213 }
214 
215 static inline int
216 unw_set_ar (struct unw_frame_info *i, int n, unsigned long v)
217 {
218 	return unw_access_ar(i, n, &v, 1);
219 }
220 
221 static inline int
222 unw_set_pr (struct unw_frame_info *i, unsigned long v)
223 {
224 	return unw_access_pr(i, &v, 1);
225 }
226 
227 #define unw_get_gr(i,n,v,nat)	unw_access_gr(i,n,v,nat,0)
228 #define unw_get_br(i,n,v)	unw_access_br(i,n,v,0)
229 #define unw_get_fr(i,n,v)	unw_access_fr(i,n,v,0)
230 #define unw_get_ar(i,n,v)	unw_access_ar(i,n,v,0)
231 #define unw_get_pr(i,v)		unw_access_pr(i,v,0)
232 
233 #endif /* _ASM_UNWIND_H */
234