194 lines
3.9 KiB
ArmAsm
194 lines
3.9 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>
|
|
#include <asm/fpu.h>
|
|
|
|
|
|
|
|
#ifdef CONFIG_HWZOL
|
|
.macro pop_zol
|
|
mtusr $r14, $LB
|
|
mtusr $r15, $LE
|
|
mtusr $r16, $LC
|
|
.endm
|
|
#endif
|
|
|
|
.macro restore_user_regs_first
|
|
setgie.d
|
|
isb
|
|
#if defined(CONFIG_FPU)
|
|
addi $sp, $sp, OSP_OFFSET
|
|
lmw.adm $r12, [$sp], $r25, #0x0
|
|
sethi $p0, hi20(has_fpu)
|
|
lbsi $p0, [$p0+lo12(has_fpu)]
|
|
beqz $p0, 2f
|
|
mtsr $r25, $FUCOP_CTL
|
|
2:
|
|
#else
|
|
addi $sp, $sp, FUCOP_CTL_OFFSET
|
|
lmw.adm $r12, [$sp], $r24, #0x0
|
|
#endif
|
|
mtsr $r12, $SP_USR
|
|
mtsr $r13, $IPC
|
|
#ifdef CONFIG_HWZOL
|
|
pop_zol
|
|
#endif
|
|
mtsr $r19, $PSW
|
|
mtsr $r20, $IPSW
|
|
mtsr $r21, $P_IPSW
|
|
mtsr $r22, $P_IPC
|
|
mtsr $r23, $P_P0
|
|
mtsr $r24, $P_P1
|
|
lmw.adm $sp, [$sp], $sp, #0xe
|
|
.endm
|
|
|
|
.macro restore_user_regs_last
|
|
pop $p0
|
|
cmovn $sp, $p0, $p0
|
|
|
|
iret
|
|
nop
|
|
|
|
.endm
|
|
|
|
.macro restore_user_regs
|
|
restore_user_regs_first
|
|
lmw.adm $r0, [$sp], $r25, #0x0
|
|
addi $sp, $sp, OSP_OFFSET
|
|
restore_user_regs_last
|
|
.endm
|
|
|
|
.macro fast_restore_user_regs
|
|
restore_user_regs_first
|
|
lmw.adm $r1, [$sp], $r25, #0x0
|
|
addi $sp, $sp, OSP_OFFSET-4
|
|
restore_user_regs_last
|
|
.endm
|
|
|
|
#ifdef CONFIG_PREEMPTION
|
|
.macro preempt_stop
|
|
.endm
|
|
#else
|
|
.macro preempt_stop
|
|
setgie.d
|
|
isb
|
|
.endm
|
|
#define resume_kernel no_work_pending
|
|
#endif
|
|
|
|
ENTRY(ret_from_exception)
|
|
preempt_stop
|
|
ENTRY(ret_from_intr)
|
|
|
|
/*
|
|
* judge Kernel or user mode
|
|
*
|
|
*/
|
|
lwi $p0, [$sp+(#IPSW_OFFSET)] ! Check if in nested interrupt
|
|
andi $p0, $p0, #PSW_mskINTL
|
|
bnez $p0, resume_kernel ! done with iret
|
|
j resume_userspace
|
|
|
|
|
|
/*
|
|
* This is the fast syscall return path. We do as little as
|
|
* possible here, and this includes saving $r0 back into the SVC
|
|
* stack.
|
|
* fixed: tsk - $r25, syscall # - $r7, syscall table pointer - $r8
|
|
*/
|
|
ENTRY(ret_fast_syscall)
|
|
gie_disable
|
|
lwi $r1, [tsk+#TSK_TI_FLAGS]
|
|
andi $p1, $r1, #_TIF_WORK_MASK
|
|
bnez $p1, fast_work_pending
|
|
fast_restore_user_regs ! iret
|
|
|
|
/*
|
|
* Ok, we need to do extra processing,
|
|
* enter the slow path returning from syscall, while pending work.
|
|
*/
|
|
fast_work_pending:
|
|
swi $r0, [$sp+(#R0_OFFSET)] ! what is different from ret_from_exception
|
|
work_pending:
|
|
andi $p1, $r1, #_TIF_NEED_RESCHED
|
|
bnez $p1, work_resched
|
|
|
|
andi $p1, $r1, #_TIF_SIGPENDING|#_TIF_NOTIFY_RESUME|#_TIF_NOTIFY_SIGNAL
|
|
beqz $p1, no_work_pending
|
|
|
|
move $r0, $sp ! 'regs'
|
|
gie_enable
|
|
bal do_notify_resume
|
|
b ret_slow_syscall
|
|
work_resched:
|
|
bal schedule ! path, return to user mode
|
|
|
|
/*
|
|
* "slow" syscall return path.
|
|
*/
|
|
ENTRY(resume_userspace)
|
|
ENTRY(ret_slow_syscall)
|
|
gie_disable
|
|
lwi $p0, [$sp+(#IPSW_OFFSET)] ! Check if in nested interrupt
|
|
andi $p0, $p0, #PSW_mskINTL
|
|
bnez $p0, no_work_pending ! done with iret
|
|
lwi $r1, [tsk+#TSK_TI_FLAGS]
|
|
andi $p1, $r1, #_TIF_WORK_MASK
|
|
bnez $p1, work_pending ! handle work_resched, sig_pend
|
|
|
|
no_work_pending:
|
|
#ifdef CONFIG_TRACE_IRQFLAGS
|
|
lwi $p0, [$sp+(#IPSW_OFFSET)]
|
|
andi $p0, $p0, #0x1
|
|
la $r10, __trace_hardirqs_off
|
|
la $r9, __trace_hardirqs_on
|
|
cmovz $r9, $p0, $r10
|
|
jral $r9
|
|
#endif
|
|
restore_user_regs ! return from iret
|
|
|
|
|
|
/*
|
|
* preemptive kernel
|
|
*/
|
|
#ifdef CONFIG_PREEMPTION
|
|
resume_kernel:
|
|
gie_disable
|
|
lwi $t0, [tsk+#TSK_TI_PREEMPT]
|
|
bnez $t0, no_work_pending
|
|
|
|
lwi $t0, [tsk+#TSK_TI_FLAGS]
|
|
andi $p1, $t0, #_TIF_NEED_RESCHED
|
|
beqz $p1, no_work_pending
|
|
|
|
lwi $t0, [$sp+(#IPSW_OFFSET)] ! Interrupts off?
|
|
andi $t0, $t0, #1
|
|
beqz $t0, no_work_pending
|
|
|
|
jal preempt_schedule_irq
|
|
b no_work_pending
|
|
#endif
|
|
|
|
/*
|
|
* This is how we return from a fork.
|
|
*/
|
|
ENTRY(ret_from_fork)
|
|
bal schedule_tail
|
|
beqz $r6, 1f ! r6 stores fn for kernel thread
|
|
move $r0, $r7 ! prepare kernel thread arg
|
|
jral $r6
|
|
1:
|
|
lwi $r1, [tsk+#TSK_TI_FLAGS] ! check for syscall tracing
|
|
andi $p1, $r1, #_TIF_WORK_SYSCALL_LEAVE ! are we tracing syscalls?
|
|
beqz $p1, ret_slow_syscall
|
|
move $r0, $sp
|
|
bal syscall_trace_leave
|
|
b ret_slow_syscall
|