Loading...
1/* SPDX-License-Identifier: GPL-2.0 */
2/* Copyright (C) 2017 Andes Technology Corporation */
3
4#include <linux/init.h>
5#include <linux/linkage.h>
6#include <asm/asm.h>
7#include <asm/csr.h>
8#include <asm/unistd.h>
9#include <asm/thread_info.h>
10#include <asm/asm-offsets.h>
11#include <asm-generic/export.h>
12#include <asm/ftrace.h>
13
14 .text
15
16 .macro SAVE_ABI_STATE
17#ifdef CONFIG_FUNCTION_GRAPH_TRACER
18 addi sp, sp, -48
19 sd s0, 32(sp)
20 sd ra, 40(sp)
21 addi s0, sp, 48
22 sd t0, 24(sp)
23 sd t1, 16(sp)
24#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
25 sd t2, 8(sp)
26#endif
27#else
28 addi sp, sp, -16
29 sd s0, 0(sp)
30 sd ra, 8(sp)
31 addi s0, sp, 16
32#endif
33 .endm
34
35 .macro RESTORE_ABI_STATE
36#ifdef CONFIG_FUNCTION_GRAPH_TRACER
37 ld s0, 32(sp)
38 ld ra, 40(sp)
39 addi sp, sp, 48
40#else
41 ld ra, 8(sp)
42 ld s0, 0(sp)
43 addi sp, sp, 16
44#endif
45 .endm
46
47 .macro RESTORE_GRAPH_ARGS
48 ld a0, 24(sp)
49 ld a1, 16(sp)
50#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
51 ld a2, 8(sp)
52#endif
53 .endm
54
55ENTRY(ftrace_graph_caller)
56 addi sp, sp, -16
57 sd s0, 0(sp)
58 sd ra, 8(sp)
59 addi s0, sp, 16
60ftrace_graph_call:
61 .global ftrace_graph_call
62 /*
63 * Calling ftrace_enable/disable_ftrace_graph_caller would overwrite the
64 * call below. Check ftrace_modify_all_code for details.
65 */
66 call ftrace_stub
67 ld ra, 8(sp)
68 ld s0, 0(sp)
69 addi sp, sp, 16
70 ret
71ENDPROC(ftrace_graph_caller)
72
73ENTRY(ftrace_caller)
74 /*
75 * a0: the address in the caller when calling ftrace_caller
76 * a1: the caller's return address
77 * a2: the address of global variable function_trace_op
78 */
79 ld a1, -8(s0)
80 addi a0, ra, -MCOUNT_INSN_SIZE
81 la t5, function_trace_op
82 ld a2, 0(t5)
83
84#ifdef CONFIG_FUNCTION_GRAPH_TRACER
85 /*
86 * the graph tracer (specifically, prepare_ftrace_return) needs these
87 * arguments but for now the function tracer occupies the regs, so we
88 * save them in temporary regs to recover later.
89 */
90 addi t0, s0, -8
91 mv t1, a0
92#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
93 ld t2, -16(s0)
94#endif
95#endif
96
97 SAVE_ABI_STATE
98ftrace_call:
99 .global ftrace_call
100 /*
101 * For the dynamic ftrace to work, here we should reserve at least
102 * 8 bytes for a functional auipc-jalr pair. The following call
103 * serves this purpose.
104 *
105 * Calling ftrace_update_ftrace_func would overwrite the nops below.
106 * Check ftrace_modify_all_code for details.
107 */
108 call ftrace_stub
109
110#ifdef CONFIG_FUNCTION_GRAPH_TRACER
111 RESTORE_GRAPH_ARGS
112 call ftrace_graph_caller
113#endif
114
115 RESTORE_ABI_STATE
116 ret
117ENDPROC(ftrace_caller)
118
119#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
120 .macro SAVE_ALL
121 addi sp, sp, -(PT_SIZE_ON_STACK+16)
122 sd s0, (PT_SIZE_ON_STACK)(sp)
123 sd ra, (PT_SIZE_ON_STACK+8)(sp)
124 addi s0, sp, (PT_SIZE_ON_STACK+16)
125
126 sd x1, PT_RA(sp)
127 sd x2, PT_SP(sp)
128 sd x3, PT_GP(sp)
129 sd x4, PT_TP(sp)
130 sd x5, PT_T0(sp)
131 sd x6, PT_T1(sp)
132 sd x7, PT_T2(sp)
133 sd x8, PT_S0(sp)
134 sd x9, PT_S1(sp)
135 sd x10, PT_A0(sp)
136 sd x11, PT_A1(sp)
137 sd x12, PT_A2(sp)
138 sd x13, PT_A3(sp)
139 sd x14, PT_A4(sp)
140 sd x15, PT_A5(sp)
141 sd x16, PT_A6(sp)
142 sd x17, PT_A7(sp)
143 sd x18, PT_S2(sp)
144 sd x19, PT_S3(sp)
145 sd x20, PT_S4(sp)
146 sd x21, PT_S5(sp)
147 sd x22, PT_S6(sp)
148 sd x23, PT_S7(sp)
149 sd x24, PT_S8(sp)
150 sd x25, PT_S9(sp)
151 sd x26, PT_S10(sp)
152 sd x27, PT_S11(sp)
153 sd x28, PT_T3(sp)
154 sd x29, PT_T4(sp)
155 sd x30, PT_T5(sp)
156 sd x31, PT_T6(sp)
157 .endm
158
159 .macro RESTORE_ALL
160 ld x1, PT_RA(sp)
161 ld x2, PT_SP(sp)
162 ld x3, PT_GP(sp)
163 ld x4, PT_TP(sp)
164 ld x5, PT_T0(sp)
165 ld x6, PT_T1(sp)
166 ld x7, PT_T2(sp)
167 ld x8, PT_S0(sp)
168 ld x9, PT_S1(sp)
169 ld x10, PT_A0(sp)
170 ld x11, PT_A1(sp)
171 ld x12, PT_A2(sp)
172 ld x13, PT_A3(sp)
173 ld x14, PT_A4(sp)
174 ld x15, PT_A5(sp)
175 ld x16, PT_A6(sp)
176 ld x17, PT_A7(sp)
177 ld x18, PT_S2(sp)
178 ld x19, PT_S3(sp)
179 ld x20, PT_S4(sp)
180 ld x21, PT_S5(sp)
181 ld x22, PT_S6(sp)
182 ld x23, PT_S7(sp)
183 ld x24, PT_S8(sp)
184 ld x25, PT_S9(sp)
185 ld x26, PT_S10(sp)
186 ld x27, PT_S11(sp)
187 ld x28, PT_T3(sp)
188 ld x29, PT_T4(sp)
189 ld x30, PT_T5(sp)
190 ld x31, PT_T6(sp)
191
192 ld s0, (PT_SIZE_ON_STACK)(sp)
193 ld ra, (PT_SIZE_ON_STACK+8)(sp)
194 addi sp, sp, (PT_SIZE_ON_STACK+16)
195 .endm
196
197 .macro RESTORE_GRAPH_REG_ARGS
198 ld a0, PT_T0(sp)
199 ld a1, PT_T1(sp)
200#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
201 ld a2, PT_T2(sp)
202#endif
203 .endm
204
205/*
206 * Most of the contents are the same as ftrace_caller.
207 */
208ENTRY(ftrace_regs_caller)
209 /*
210 * a3: the address of all registers in the stack
211 */
212 ld a1, -8(s0)
213 addi a0, ra, -MCOUNT_INSN_SIZE
214 la t5, function_trace_op
215 ld a2, 0(t5)
216 addi a3, sp, -(PT_SIZE_ON_STACK+16)
217
218#ifdef CONFIG_FUNCTION_GRAPH_TRACER
219 addi t0, s0, -8
220 mv t1, a0
221#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
222 ld t2, -16(s0)
223#endif
224#endif
225 SAVE_ALL
226
227ftrace_regs_call:
228 .global ftrace_regs_call
229 call ftrace_stub
230
231#ifdef CONFIG_FUNCTION_GRAPH_TRACER
232 RESTORE_GRAPH_REG_ARGS
233 call ftrace_graph_caller
234#endif
235
236 RESTORE_ALL
237 ret
238ENDPROC(ftrace_regs_caller)
239#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */
1/* SPDX-License-Identifier: GPL-2.0 */
2/* Copyright (C) 2017 Andes Technology Corporation */
3
4#include <linux/init.h>
5#include <linux/linkage.h>
6#include <linux/export.h>
7#include <asm/asm.h>
8#include <asm/csr.h>
9#include <asm/unistd.h>
10#include <asm/thread_info.h>
11#include <asm/asm-offsets.h>
12#include <asm/ftrace.h>
13
14 .text
15
16#define FENTRY_RA_OFFSET 8
17#define ABI_SIZE_ON_STACK 80
18#define ABI_A0 0
19#define ABI_A1 8
20#define ABI_A2 16
21#define ABI_A3 24
22#define ABI_A4 32
23#define ABI_A5 40
24#define ABI_A6 48
25#define ABI_A7 56
26#define ABI_T0 64
27#define ABI_RA 72
28
29 .macro SAVE_ABI
30 addi sp, sp, -ABI_SIZE_ON_STACK
31
32 REG_S a0, ABI_A0(sp)
33 REG_S a1, ABI_A1(sp)
34 REG_S a2, ABI_A2(sp)
35 REG_S a3, ABI_A3(sp)
36 REG_S a4, ABI_A4(sp)
37 REG_S a5, ABI_A5(sp)
38 REG_S a6, ABI_A6(sp)
39 REG_S a7, ABI_A7(sp)
40 REG_S t0, ABI_T0(sp)
41 REG_S ra, ABI_RA(sp)
42 .endm
43
44 .macro RESTORE_ABI
45 REG_L a0, ABI_A0(sp)
46 REG_L a1, ABI_A1(sp)
47 REG_L a2, ABI_A2(sp)
48 REG_L a3, ABI_A3(sp)
49 REG_L a4, ABI_A4(sp)
50 REG_L a5, ABI_A5(sp)
51 REG_L a6, ABI_A6(sp)
52 REG_L a7, ABI_A7(sp)
53 REG_L t0, ABI_T0(sp)
54 REG_L ra, ABI_RA(sp)
55
56 addi sp, sp, ABI_SIZE_ON_STACK
57 .endm
58
59#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
60
61/**
62* SAVE_ABI_REGS - save regs against the ftrace_regs struct
63*
64* After the stack is established,
65*
66* 0(sp) stores the PC of the traced function which can be accessed
67* by &(fregs)->epc in tracing function. Note that the real
68* function entry address should be computed with -FENTRY_RA_OFFSET.
69*
70* 8(sp) stores the function return address (i.e. parent IP) that
71* can be accessed by &(fregs)->ra in tracing function.
72*
73* The other regs are saved at the respective localtion and accessed
74* by the respective ftrace_regs member.
75*
76* Here is the layout of stack for your reference.
77*
78* PT_SIZE_ON_STACK -> +++++++++
79* + ..... +
80* + a0-a7 + --++++-> ftrace_caller saved
81* + t1 + --++++-> direct tramp address
82* + s0 + --+ // frame pointer
83* + sp + +
84* + ra + --+ // parent IP
85* sp -> + epc + --+ // PC
86* +++++++++
87**/
88 .macro SAVE_ABI_REGS
89 mv t4, sp // Save original SP in T4
90 addi sp, sp, -FREGS_SIZE_ON_STACK
91
92 REG_S t0, FREGS_EPC(sp)
93 REG_S x1, FREGS_RA(sp)
94 REG_S t4, FREGS_SP(sp) // Put original SP on stack
95#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
96 REG_S x8, FREGS_S0(sp)
97#endif
98 REG_S x6, FREGS_T1(sp)
99
100 // save the arguments
101 REG_S x10, FREGS_A0(sp)
102 REG_S x11, FREGS_A1(sp)
103 REG_S x12, FREGS_A2(sp)
104 REG_S x13, FREGS_A3(sp)
105 REG_S x14, FREGS_A4(sp)
106 REG_S x15, FREGS_A5(sp)
107 REG_S x16, FREGS_A6(sp)
108 REG_S x17, FREGS_A7(sp)
109 .endm
110
111 .macro RESTORE_ABI_REGS, all=0
112 REG_L t0, FREGS_EPC(sp)
113 REG_L x1, FREGS_RA(sp)
114#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
115 REG_L x8, FREGS_S0(sp)
116#endif
117 REG_L x6, FREGS_T1(sp)
118
119 // restore the arguments
120 REG_L x10, FREGS_A0(sp)
121 REG_L x11, FREGS_A1(sp)
122 REG_L x12, FREGS_A2(sp)
123 REG_L x13, FREGS_A3(sp)
124 REG_L x14, FREGS_A4(sp)
125 REG_L x15, FREGS_A5(sp)
126 REG_L x16, FREGS_A6(sp)
127 REG_L x17, FREGS_A7(sp)
128
129 addi sp, sp, FREGS_SIZE_ON_STACK
130 .endm
131
132 .macro PREPARE_ARGS
133 addi a0, t0, -FENTRY_RA_OFFSET
134 la a1, function_trace_op
135 REG_L a2, 0(a1)
136 mv a1, ra
137 mv a3, sp
138 .endm
139
140#endif /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */
141
142#ifndef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
143SYM_FUNC_START(ftrace_caller)
144 SAVE_ABI
145
146 addi a0, t0, -FENTRY_RA_OFFSET
147 la a1, function_trace_op
148 REG_L a2, 0(a1)
149 mv a1, ra
150 mv a3, sp
151
152SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL)
153 call ftrace_stub
154
155#ifdef CONFIG_FUNCTION_GRAPH_TRACER
156 addi a0, sp, ABI_RA
157 REG_L a1, ABI_T0(sp)
158 addi a1, a1, -FENTRY_RA_OFFSET
159#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
160 mv a2, s0
161#endif
162SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL)
163 call ftrace_stub
164#endif
165 RESTORE_ABI
166 jr t0
167SYM_FUNC_END(ftrace_caller)
168
169#else /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */
170SYM_FUNC_START(ftrace_caller)
171 mv t1, zero
172 SAVE_ABI_REGS
173 PREPARE_ARGS
174
175SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL)
176 call ftrace_stub
177
178 RESTORE_ABI_REGS
179 bnez t1, .Ldirect
180 jr t0
181.Ldirect:
182 jr t1
183SYM_FUNC_END(ftrace_caller)
184
185#endif /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */
186
187#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
188SYM_CODE_START(ftrace_stub_direct_tramp)
189 jr t0
190SYM_CODE_END(ftrace_stub_direct_tramp)
191#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */