1 /*
2  * Copyright (C) 2009 Matt Fleming <matt@console-pimps.org>
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  */
9 #ifndef __ASM_SH_DWARF_H
10 #define __ASM_SH_DWARF_H
11 
12 #ifdef CONFIG_DWARF_UNWINDER
13 
14 /*
15  * DWARF expression operations
16  */
17 #define DW_OP_addr	0x03
18 #define DW_OP_deref	0x06
19 #define DW_OP_const1u	0x08
20 #define DW_OP_const1s	0x09
21 #define DW_OP_const2u	0x0a
22 #define DW_OP_const2s	0x0b
23 #define DW_OP_const4u	0x0c
24 #define DW_OP_const4s	0x0d
25 #define DW_OP_const8u	0x0e
26 #define DW_OP_const8s	0x0f
27 #define DW_OP_constu	0x10
28 #define DW_OP_consts	0x11
29 #define DW_OP_dup	0x12
30 #define DW_OP_drop	0x13
31 #define DW_OP_over	0x14
32 #define DW_OP_pick	0x15
33 #define DW_OP_swap	0x16
34 #define DW_OP_rot	0x17
35 #define DW_OP_xderef	0x18
36 #define DW_OP_abs	0x19
37 #define DW_OP_and	0x1a
38 #define DW_OP_div	0x1b
39 #define DW_OP_minus	0x1c
40 #define DW_OP_mod	0x1d
41 #define DW_OP_mul	0x1e
42 #define DW_OP_neg	0x1f
43 #define DW_OP_not	0x20
44 #define DW_OP_or	0x21
45 #define DW_OP_plus	0x22
46 #define DW_OP_plus_uconst	0x23
47 #define DW_OP_shl	0x24
48 #define DW_OP_shr	0x25
49 #define DW_OP_shra	0x26
50 #define DW_OP_xor	0x27
51 #define DW_OP_skip	0x2f
52 #define DW_OP_bra	0x28
53 #define DW_OP_eq	0x29
54 #define DW_OP_ge	0x2a
55 #define DW_OP_gt	0x2b
56 #define DW_OP_le	0x2c
57 #define DW_OP_lt	0x2d
58 #define DW_OP_ne	0x2e
59 #define DW_OP_lit0	0x30
60 #define DW_OP_lit1	0x31
61 #define DW_OP_lit2	0x32
62 #define DW_OP_lit3	0x33
63 #define DW_OP_lit4	0x34
64 #define DW_OP_lit5	0x35
65 #define DW_OP_lit6	0x36
66 #define DW_OP_lit7	0x37
67 #define DW_OP_lit8	0x38
68 #define DW_OP_lit9	0x39
69 #define DW_OP_lit10	0x3a
70 #define DW_OP_lit11	0x3b
71 #define DW_OP_lit12	0x3c
72 #define DW_OP_lit13	0x3d
73 #define DW_OP_lit14	0x3e
74 #define DW_OP_lit15	0x3f
75 #define DW_OP_lit16	0x40
76 #define DW_OP_lit17	0x41
77 #define DW_OP_lit18	0x42
78 #define DW_OP_lit19	0x43
79 #define DW_OP_lit20	0x44
80 #define DW_OP_lit21	0x45
81 #define DW_OP_lit22	0x46
82 #define DW_OP_lit23	0x47
83 #define DW_OP_lit24	0x48
84 #define DW_OP_lit25	0x49
85 #define DW_OP_lit26	0x4a
86 #define DW_OP_lit27	0x4b
87 #define DW_OP_lit28	0x4c
88 #define DW_OP_lit29	0x4d
89 #define DW_OP_lit30	0x4e
90 #define DW_OP_lit31	0x4f
91 #define DW_OP_reg0	0x50
92 #define DW_OP_reg1	0x51
93 #define DW_OP_reg2	0x52
94 #define DW_OP_reg3	0x53
95 #define DW_OP_reg4	0x54
96 #define DW_OP_reg5	0x55
97 #define DW_OP_reg6	0x56
98 #define DW_OP_reg7	0x57
99 #define DW_OP_reg8	0x58
100 #define DW_OP_reg9	0x59
101 #define DW_OP_reg10	0x5a
102 #define DW_OP_reg11	0x5b
103 #define DW_OP_reg12	0x5c
104 #define DW_OP_reg13	0x5d
105 #define DW_OP_reg14	0x5e
106 #define DW_OP_reg15	0x5f
107 #define DW_OP_reg16	0x60
108 #define DW_OP_reg17	0x61
109 #define DW_OP_reg18	0x62
110 #define DW_OP_reg19	0x63
111 #define DW_OP_reg20	0x64
112 #define DW_OP_reg21	0x65
113 #define DW_OP_reg22	0x66
114 #define DW_OP_reg23	0x67
115 #define DW_OP_reg24	0x68
116 #define DW_OP_reg25	0x69
117 #define DW_OP_reg26	0x6a
118 #define DW_OP_reg27	0x6b
119 #define DW_OP_reg28	0x6c
120 #define DW_OP_reg29	0x6d
121 #define DW_OP_reg30	0x6e
122 #define DW_OP_reg31	0x6f
123 #define DW_OP_breg0	0x70
124 #define DW_OP_breg1	0x71
125 #define DW_OP_breg2	0x72
126 #define DW_OP_breg3	0x73
127 #define DW_OP_breg4	0x74
128 #define DW_OP_breg5	0x75
129 #define DW_OP_breg6	0x76
130 #define DW_OP_breg7	0x77
131 #define DW_OP_breg8	0x78
132 #define DW_OP_breg9	0x79
133 #define DW_OP_breg10	0x7a
134 #define DW_OP_breg11	0x7b
135 #define DW_OP_breg12	0x7c
136 #define DW_OP_breg13	0x7d
137 #define DW_OP_breg14	0x7e
138 #define DW_OP_breg15	0x7f
139 #define DW_OP_breg16	0x80
140 #define DW_OP_breg17	0x81
141 #define DW_OP_breg18	0x82
142 #define DW_OP_breg19	0x83
143 #define DW_OP_breg20	0x84
144 #define DW_OP_breg21	0x85
145 #define DW_OP_breg22	0x86
146 #define DW_OP_breg23	0x87
147 #define DW_OP_breg24	0x88
148 #define DW_OP_breg25	0x89
149 #define DW_OP_breg26	0x8a
150 #define DW_OP_breg27	0x8b
151 #define DW_OP_breg28	0x8c
152 #define DW_OP_breg29	0x8d
153 #define DW_OP_breg30	0x8e
154 #define DW_OP_breg31	0x8f
155 #define DW_OP_regx	0x90
156 #define DW_OP_fbreg	0x91
157 #define DW_OP_bregx	0x92
158 #define DW_OP_piece	0x93
159 #define DW_OP_deref_size	0x94
160 #define DW_OP_xderef_size	0x95
161 #define DW_OP_nop	0x96
162 #define DW_OP_push_object_address	0x97
163 #define DW_OP_call2	0x98
164 #define DW_OP_call4	0x99
165 #define DW_OP_call_ref	0x9a
166 #define DW_OP_form_tls_address	0x9b
167 #define DW_OP_call_frame_cfa	0x9c
168 #define DW_OP_bit_piece	0x9d
169 #define DW_OP_lo_user	0xe0
170 #define DW_OP_hi_user	0xff
171 
172 /*
173  * Addresses used in FDE entries in the .eh_frame section may be encoded
174  * using one of the following encodings.
175  */
176 #define DW_EH_PE_absptr	0x00
177 #define DW_EH_PE_omit	0xff
178 #define DW_EH_PE_uleb128	0x01
179 #define DW_EH_PE_udata2	0x02
180 #define DW_EH_PE_udata4	0x03
181 #define DW_EH_PE_udata8	0x04
182 #define DW_EH_PE_sleb128	0x09
183 #define DW_EH_PE_sdata2	0x0a
184 #define DW_EH_PE_sdata4	0x0b
185 #define DW_EH_PE_sdata8	0x0c
186 #define DW_EH_PE_signed	0x09
187 
188 #define DW_EH_PE_pcrel	0x10
189 
190 /*
191  * The architecture-specific register number that contains the return
192  * address in the .debug_frame table.
193  */
194 #define DWARF_ARCH_RA_REG	17
195 
196 #ifndef __ASSEMBLY__
197 
198 #include <linux/compiler.h>
199 #include <linux/bug.h>
200 #include <linux/list.h>
201 #include <linux/module.h>
202 
203 /*
204  * Read either the frame pointer (r14) or the stack pointer (r15).
205  * NOTE: this MUST be inlined.
206  */
dwarf_read_arch_reg(unsigned int reg)207 static __always_inline unsigned long dwarf_read_arch_reg(unsigned int reg)
208 {
209 	unsigned long value = 0;
210 
211 	switch (reg) {
212 	case 14:
213 		__asm__ __volatile__("mov r14, %0\n" : "=r" (value));
214 		break;
215 	case 15:
216 		__asm__ __volatile__("mov r15, %0\n" : "=r" (value));
217 		break;
218 	default:
219 		BUG();
220 	}
221 
222 	return value;
223 }
224 
225 /**
226  *	dwarf_cie - Common Information Entry
227  */
228 struct dwarf_cie {
229 	unsigned long length;
230 	unsigned long cie_id;
231 	unsigned char version;
232 	const char *augmentation;
233 	unsigned int code_alignment_factor;
234 	int data_alignment_factor;
235 
236 	/* Which column in the rule table represents return addr of func. */
237 	unsigned int return_address_reg;
238 
239 	unsigned char *initial_instructions;
240 	unsigned char *instructions_end;
241 
242 	unsigned char encoding;
243 
244 	unsigned long cie_pointer;
245 
246 	unsigned long flags;
247 #define DWARF_CIE_Z_AUGMENTATION	(1 << 0)
248 
249 	/* linked-list entry if this CIE is from a module */
250 	struct list_head link;
251 
252 	struct rb_node node;
253 };
254 
255 /**
256  *	dwarf_fde - Frame Description Entry
257  */
258 struct dwarf_fde {
259 	unsigned long length;
260 	unsigned long cie_pointer;
261 	struct dwarf_cie *cie;
262 	unsigned long initial_location;
263 	unsigned long address_range;
264 	unsigned char *instructions;
265 	unsigned char *end;
266 
267 	/* linked-list entry if this FDE is from a module */
268 	struct list_head link;
269 
270 	struct rb_node node;
271 };
272 
273 /**
274  *	dwarf_frame - DWARF information for a frame in the call stack
275  */
276 struct dwarf_frame {
277 	struct dwarf_frame *prev, *next;
278 
279 	unsigned long pc;
280 
281 	struct list_head reg_list;
282 
283 	unsigned long cfa;
284 
285 	/* Valid when DW_FRAME_CFA_REG_OFFSET is set in flags */
286 	unsigned int cfa_register;
287 	unsigned int cfa_offset;
288 
289 	/* Valid when DW_FRAME_CFA_REG_EXP is set in flags */
290 	unsigned char *cfa_expr;
291 	unsigned int cfa_expr_len;
292 
293 	unsigned long flags;
294 #define DWARF_FRAME_CFA_REG_OFFSET	(1 << 0)
295 #define DWARF_FRAME_CFA_REG_EXP		(1 << 1)
296 
297 	unsigned long return_addr;
298 };
299 
300 /**
301  *	dwarf_reg - DWARF register
302  *	@flags: Describes how to calculate the value of this register
303  */
304 struct dwarf_reg {
305 	struct list_head link;
306 
307 	unsigned int number;
308 
309 	unsigned long addr;
310 	unsigned long flags;
311 #define DWARF_REG_OFFSET	(1 << 0)
312 #define DWARF_VAL_OFFSET	(1 << 1)
313 #define DWARF_UNDEFINED		(1 << 2)
314 };
315 
316 /*
317  * Call Frame instruction opcodes.
318  */
319 #define DW_CFA_advance_loc	0x40
320 #define DW_CFA_offset		0x80
321 #define DW_CFA_restore		0xc0
322 #define DW_CFA_nop		0x00
323 #define DW_CFA_set_loc		0x01
324 #define DW_CFA_advance_loc1	0x02
325 #define DW_CFA_advance_loc2	0x03
326 #define DW_CFA_advance_loc4	0x04
327 #define DW_CFA_offset_extended	0x05
328 #define DW_CFA_restore_extended	0x06
329 #define DW_CFA_undefined	0x07
330 #define DW_CFA_same_value	0x08
331 #define DW_CFA_register		0x09
332 #define DW_CFA_remember_state	0x0a
333 #define DW_CFA_restore_state	0x0b
334 #define DW_CFA_def_cfa		0x0c
335 #define DW_CFA_def_cfa_register	0x0d
336 #define DW_CFA_def_cfa_offset	0x0e
337 #define DW_CFA_def_cfa_expression	0x0f
338 #define DW_CFA_expression	0x10
339 #define DW_CFA_offset_extended_sf	0x11
340 #define DW_CFA_def_cfa_sf	0x12
341 #define DW_CFA_def_cfa_offset_sf	0x13
342 #define DW_CFA_val_offset	0x14
343 #define DW_CFA_val_offset_sf	0x15
344 #define DW_CFA_val_expression	0x16
345 #define DW_CFA_lo_user		0x1c
346 #define DW_CFA_hi_user		0x3f
347 
348 /* GNU extension opcodes  */
349 #define DW_CFA_GNU_args_size	0x2e
350 #define DW_CFA_GNU_negative_offset_extended 0x2f
351 
352 /*
353  * Some call frame instructions encode their operands in the opcode. We
354  * need some helper functions to extract both the opcode and operands
355  * from an instruction.
356  */
DW_CFA_opcode(unsigned long insn)357 static inline unsigned int DW_CFA_opcode(unsigned long insn)
358 {
359 	return (insn & 0xc0);
360 }
361 
DW_CFA_operand(unsigned long insn)362 static inline unsigned int DW_CFA_operand(unsigned long insn)
363 {
364 	return (insn & 0x3f);
365 }
366 
367 #define DW_EH_FRAME_CIE	0		/* .eh_frame CIE IDs are 0 */
368 #define DW_CIE_ID	0xffffffff
369 #define DW64_CIE_ID	0xffffffffffffffffULL
370 
371 /*
372  * DWARF FDE/CIE length field values.
373  */
374 #define DW_EXT_LO	0xfffffff0
375 #define DW_EXT_HI	0xffffffff
376 #define DW_EXT_DWARF64	DW_EXT_HI
377 
378 extern struct dwarf_frame *dwarf_unwind_stack(unsigned long,
379 					      struct dwarf_frame *);
380 extern void dwarf_free_frame(struct dwarf_frame *);
381 
382 extern int module_dwarf_finalize(const Elf_Ehdr *, const Elf_Shdr *,
383 				 struct module *);
384 extern void module_dwarf_cleanup(struct module *);
385 
386 #endif /* !__ASSEMBLY__ */
387 
388 #define CFI_STARTPROC	.cfi_startproc
389 #define CFI_ENDPROC	.cfi_endproc
390 #define CFI_DEF_CFA	.cfi_def_cfa
391 #define CFI_REGISTER	.cfi_register
392 #define CFI_REL_OFFSET	.cfi_rel_offset
393 #define CFI_UNDEFINED	.cfi_undefined
394 
395 #else
396 
397 /*
398  * Use the asm comment character to ignore the rest of the line.
399  */
400 #define CFI_IGNORE	!
401 
402 #define CFI_STARTPROC	CFI_IGNORE
403 #define CFI_ENDPROC	CFI_IGNORE
404 #define CFI_DEF_CFA	CFI_IGNORE
405 #define CFI_REGISTER	CFI_IGNORE
406 #define CFI_REL_OFFSET	CFI_IGNORE
407 #define CFI_UNDEFINED	CFI_IGNORE
408 
409 #ifndef __ASSEMBLY__
dwarf_unwinder_init(void)410 static inline void dwarf_unwinder_init(void)
411 {
412 }
413 
414 #define module_dwarf_finalize(hdr, sechdrs, me)	(0)
415 #define module_dwarf_cleanup(mod)		do { } while (0)
416 
417 #endif
418 
419 #endif /* CONFIG_DWARF_UNWINDER */
420 
421 #endif /* __ASM_SH_DWARF_H */
422