mirror of https://gitee.com/openkylin/linux.git
101 lines
2.2 KiB
ArmAsm
101 lines
2.2 KiB
ArmAsm
// SPDX-License-Identifier: GPL-2.0
|
|
// Copyright (C) 2005-2017 Andes Technology Corporation
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/unistd.h>
|
|
#include <asm/assembler.h>
|
|
#include <asm/nds32.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/thread_info.h>
|
|
#include <asm/current.h>
|
|
|
|
/*
|
|
* $r0 = previous task_struct,
|
|
* $r1 = next task_struct,
|
|
* previous and next are guaranteed not to be the same.
|
|
*/
|
|
|
|
ENTRY(__switch_to)
|
|
|
|
la $p0, __entry_task
|
|
sw $r1, [$p0]
|
|
addi $p1, $r0, #THREAD_CPU_CONTEXT
|
|
smw.bi $r6, [$p1], $r14, #0xb ! push r6~r14, fp, lp, sp
|
|
move $r25, $r1
|
|
#if defined(CONFIG_FPU)
|
|
call _switch_fpu
|
|
#endif
|
|
addi $r1, $r25, #THREAD_CPU_CONTEXT
|
|
lmw.bi $r6, [$r1], $r14, #0xb ! pop r6~r14, fp, lp, sp
|
|
ret
|
|
|
|
|
|
#define tbl $r8
|
|
|
|
/*
|
|
* $r7 will be writen as syscall nr
|
|
*/
|
|
.macro get_scno
|
|
lwi $r7, [$sp + R15_OFFSET]
|
|
swi $r7, [$sp + SYSCALLNO_OFFSET]
|
|
.endm
|
|
|
|
.macro updateipc
|
|
addi $r17, $r13, #4 ! $r13 is $IPC
|
|
swi $r17, [$sp + IPC_OFFSET]
|
|
.endm
|
|
|
|
ENTRY(eh_syscall)
|
|
updateipc
|
|
|
|
get_scno
|
|
gie_enable
|
|
|
|
lwi $p0, [tsk+#TSK_TI_FLAGS] ! check for syscall tracing
|
|
|
|
andi $p1, $p0, #_TIF_WORK_SYSCALL_ENTRY ! are we tracing syscalls?
|
|
bnez $p1, __sys_trace
|
|
|
|
la $lp, ret_fast_syscall ! return address
|
|
jmp_systbl:
|
|
addi $p1, $r7, #-__NR_syscalls ! syscall number of syscall instruction is guarded by addembler
|
|
bgez $p1, _SCNO_EXCEED ! call sys_* routine
|
|
la tbl, sys_call_table ! load syscall table pointer
|
|
slli $p1, $r7, #2
|
|
add $p1, tbl, $p1
|
|
lwi $p1, [$p1]
|
|
jr $p1 ! no return
|
|
|
|
_SCNO_EXCEED:
|
|
ori $r0, $r7, #0
|
|
ori $r1, $sp, #0
|
|
b bad_syscall
|
|
|
|
/*
|
|
* This is the really slow path. We're going to be doing
|
|
* context switches, and waiting for our parent to respond.
|
|
*/
|
|
__sys_trace:
|
|
move $r0, $sp
|
|
bal syscall_trace_enter
|
|
move $r7, $r0
|
|
la $lp, __sys_trace_return ! return address
|
|
|
|
addi $p1, $r7, #1
|
|
beqz $p1, ret_slow_syscall ! fatal signal is pending
|
|
|
|
addi $p1, $sp, #R0_OFFSET ! pointer to regs
|
|
lmw.bi $r0, [$p1], $r5 ! have to reload $r0 - $r5
|
|
b jmp_systbl
|
|
|
|
__sys_trace_return:
|
|
swi $r0, [$sp+#R0_OFFSET] ! T: save returned $r0
|
|
move $r0, $sp ! set pt_regs for syscall_trace_leave
|
|
bal syscall_trace_leave
|
|
b ret_slow_syscall
|
|
|
|
ENTRY(sys_rt_sigreturn_wrapper)
|
|
addi $r0, $sp, #0
|
|
b sys_rt_sigreturn
|
|
ENDPROC(sys_rt_sigreturn_wrapper)
|