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/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2017 Andes Technology Corporation */
#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/asm.h>
#include <asm/csr.h>
#include <asm/unistd.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm-generic/export.h>
#include <asm/ftrace.h>
.text
.macro SAVE_ABI_STATE
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
addi sp, sp, -48
sd s0, 32(sp)
sd ra, 40(sp)
addi s0, sp, 48
sd t0, 24(sp)
sd t1, 16(sp)
#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
sd t2, 8(sp)
#endif
#else
addi sp, sp, -16
sd s0, 0(sp)
sd ra, 8(sp)
addi s0, sp, 16
#endif
.endm
.macro RESTORE_ABI_STATE
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
ld s0, 32(sp)
ld ra, 40(sp)
addi sp, sp, 48
#else
ld ra, 8(sp)
ld s0, 0(sp)
addi sp, sp, 16
#endif
.endm
.macro RESTORE_GRAPH_ARGS
ld a0, 24(sp)
ld a1, 16(sp)
#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
ld a2, 8(sp)
#endif
.endm
ENTRY(ftrace_graph_caller)
addi sp, sp, -16
sd s0, 0(sp)
sd ra, 8(sp)
addi s0, sp, 16
ftrace_graph_call:
.global ftrace_graph_call
/*
* Calling ftrace_enable/disable_ftrace_graph_caller would overwrite the
* call below. Check ftrace_modify_all_code for details.
*/
call ftrace_stub
ld ra, 8(sp)
ld s0, 0(sp)
addi sp, sp, 16
ret
ENDPROC(ftrace_graph_caller)
ENTRY(ftrace_caller)
/*
* a0: the address in the caller when calling ftrace_caller
* a1: the caller's return address
* a2: the address of global variable function_trace_op
*/
ld a1, -8(s0)
addi a0, ra, -MCOUNT_INSN_SIZE
la t5, function_trace_op
ld a2, 0(t5)
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
/*
* the graph tracer (specifically, prepare_ftrace_return) needs these
* arguments but for now the function tracer occupies the regs, so we
* save them in temporary regs to recover later.
*/
addi t0, s0, -8
mv t1, a0
#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
ld t2, -16(s0)
#endif
#endif
SAVE_ABI_STATE
ftrace_call:
.global ftrace_call
/*
* For the dynamic ftrace to work, here we should reserve at least
* 8 bytes for a functional auipc-jalr pair. The following call
* serves this purpose.
*
* Calling ftrace_update_ftrace_func would overwrite the nops below.
* Check ftrace_modify_all_code for details.
*/
call ftrace_stub
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
RESTORE_GRAPH_ARGS
call ftrace_graph_caller
#endif
RESTORE_ABI_STATE
ret
ENDPROC(ftrace_caller)
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