1 // SPDX-License-Identifier: GPL-2.0
2 #include <elfutils/libdwfl.h>
3 #include <linux/kernel.h>
4 #include "perf_regs.h"
5 #include "../../../util/unwind-libdw.h"
6 #include "../../../util/perf_regs.h"
7 #include "../../../util/sample.h"
8 
9 /* See backends/ppc_initreg.c and backends/ppc_regs.c in elfutils.  */
10 static const int special_regs[3][2] = {
11 	{ 65, PERF_REG_POWERPC_LINK },
12 	{ 101, PERF_REG_POWERPC_XER },
13 	{ 109, PERF_REG_POWERPC_CTR },
14 };
15 
libdw__arch_set_initial_registers(Dwfl_Thread * thread,void * arg)16 bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
17 {
18 	struct unwind_info *ui = arg;
19 	struct regs_dump *user_regs = &ui->sample->user_regs;
20 	Dwarf_Word dwarf_regs[32], dwarf_nip;
21 	size_t i;
22 
23 #define REG(r) ({						\
24 	Dwarf_Word val = 0;					\
25 	perf_reg_value(&val, user_regs, PERF_REG_POWERPC_##r);	\
26 	val;							\
27 })
28 
29 	dwarf_regs[0]  = REG(R0);
30 	dwarf_regs[1]  = REG(R1);
31 	dwarf_regs[2]  = REG(R2);
32 	dwarf_regs[3]  = REG(R3);
33 	dwarf_regs[4]  = REG(R4);
34 	dwarf_regs[5]  = REG(R5);
35 	dwarf_regs[6]  = REG(R6);
36 	dwarf_regs[7]  = REG(R7);
37 	dwarf_regs[8]  = REG(R8);
38 	dwarf_regs[9]  = REG(R9);
39 	dwarf_regs[10] = REG(R10);
40 	dwarf_regs[11] = REG(R11);
41 	dwarf_regs[12] = REG(R12);
42 	dwarf_regs[13] = REG(R13);
43 	dwarf_regs[14] = REG(R14);
44 	dwarf_regs[15] = REG(R15);
45 	dwarf_regs[16] = REG(R16);
46 	dwarf_regs[17] = REG(R17);
47 	dwarf_regs[18] = REG(R18);
48 	dwarf_regs[19] = REG(R19);
49 	dwarf_regs[20] = REG(R20);
50 	dwarf_regs[21] = REG(R21);
51 	dwarf_regs[22] = REG(R22);
52 	dwarf_regs[23] = REG(R23);
53 	dwarf_regs[24] = REG(R24);
54 	dwarf_regs[25] = REG(R25);
55 	dwarf_regs[26] = REG(R26);
56 	dwarf_regs[27] = REG(R27);
57 	dwarf_regs[28] = REG(R28);
58 	dwarf_regs[29] = REG(R29);
59 	dwarf_regs[30] = REG(R30);
60 	dwarf_regs[31] = REG(R31);
61 	if (!dwfl_thread_state_registers(thread, 0, 32, dwarf_regs))
62 		return false;
63 
64 	dwarf_nip = REG(NIP);
65 	dwfl_thread_state_register_pc(thread, dwarf_nip);
66 	for (i = 0; i < ARRAY_SIZE(special_regs); i++) {
67 		Dwarf_Word val = 0;
68 		perf_reg_value(&val, user_regs, special_regs[i][1]);
69 		if (!dwfl_thread_state_registers(thread,
70 						 special_regs[i][0], 1,
71 						 &val))
72 			return false;
73 	}
74 
75 	return true;
76 }
77