/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2001 MIPS Technologies, Inc.
*/
#include <linux/config.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/regdef.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <asm/isadep.h>
#include <asm/thread_info.h>
#include <asm/war.h>
#ifdef CONFIG_MIPS_MT_SMTC
#include <asm/mipsmtregs.h>
#endif
#ifdef CONFIG_PREEMPT
.macro preempt_stop
.endm
#else
.macro preempt_stop
local_irq_disable
.endm
#define resume_kernel restore_all
#endif
.text
.align 5
FEXPORT(ret_from_exception)
preempt_stop
FEXPORT(ret_from_irq)
LONG_L t0, PT_STATUS(sp) # returning to kernel mode?
andi t0, t0, KU_USER
beqz t0, resume_kernel
resume_userspace:
local_irq_disable # make sure we dont miss an
# interrupt setting need_resched
# between sampling and return
LONG_L a2, TI_FLAGS($28) # current->work
andi t0, a2, _TIF_WORK_MASK # (ignoring syscall_trace)
bnez t0, work_pending
j restore_all
#ifdef CONFIG_PREEMPT
resume_kernel:
local_irq_disable
lw t0, TI_PRE_COUNT($28)
bnez t0, restore_all
need_resched:
LONG_L t0, TI_FLAGS($28)
andi t1, t0, _TIF_NEED_RESCHED
beqz t1, restore_all
LONG_L t0, PT_STATUS(sp) # Interrupts off?
andi t0, 1
beqz t0, restore_all
jal preempt_schedule_irq
b need_resched
#endif
FEXPORT(ret_from_fork)
jal schedule_tail # a0 = task_t *prev
FEXPORT(syscall_exit)
local_irq_disable # make sure need_resched and
# signals dont change between
# sampling and return
LONG_L a2, TI_FLAGS($28) # current->work
li t0, _TIF_ALLWORK_MASK
and t0, a2, t0
bnez t0, syscall_exit_work
FEXPORT(restore_all) # restore full frame
#ifdef CONFIG_MIPS_MT_SMTC
/* Detect and execute deferred IPI "interrupts" */
move a0,sp
jal deferred_smtc_ipi
/* Re-arm any temporarily masked interrupts not explicitly "acked" */
mfc0 v0, CP0_TCSTATUS
ori v1, v0, TCSTATUS_IXMT
mtc0 v1, CP0_TCSTATUS
andi v0, TCSTATUS_IXMT
ehb
mfc0 t0, CP0_TCCONTEXT
DMT 9 # dmt t1
jal mips_ihb
mfc0 t2, CP0_STATUS
andi t3, t0, 0xff00
or t2, t2, t3
mtc0 t2, CP0_STATUS
ehb
andi t1, t1, VPECONTROL_TE
beqz t1, 1f
EMT
1:
mfc0 v1, CP0_TCSTATUS
/* We set IXMT above, XOR should clear it here */
xori v1, v1, TCSTATUS_IXMT
or v1, v0, v1
mtc0 v1, CP0_TCSTATUS
ehb
xor t0, t0, t3
mtc0 t0, CP0_TCCONTEXT
#endif /* CONFIG_MIPS_MT_SMTC */
.set noat
RESTORE_TEMP
RESTORE_AT
RESTORE_STATIC
FEXPORT(restore_partial) # restore partial frame
RESTORE_SOME
RESTORE_SP_AND_RET
.set at
work_pending:
andi t0, a2, _TIF_NEED_RESCHED # a2 is preloaded with TI_FLAGS
beqz t0, work_notifysig
work_resched:
jal schedule
local_irq_disable # make sure need_resched and
# signals dont change between
# sampling and return
LONG_L a2, TI_FLAGS($28)
andi t0, a2, _TIF_WORK_MASK # is there any work to be done
# other than syscall tracing?
beqz t0, restore_all
andi t0, a2, _TIF_NEED_RESCHED
bnez t0, work_resched
work_notifysig: # deal with pending signals and
# notify-resume requests
move a0, sp
li a1, 0
jal do_notify_resume # a2 already loaded
j resume_userspace
FEXPORT(syscall_exit_work_partial)
SAVE_STATIC
syscall_exit_work:
li t0, _TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT
and t0, a2 # a2 is preloaded with TI_FLAGS
beqz t0, work_pending # trace bit set?
local_irq_enable # could let do_syscall_trace()
# call schedule() instead
move a0, sp
li a1, 1
jal do_syscall_trace
b resume_userspace
#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_MIPS_MT)
/*
* MIPS32R2 Instruction Hazard Barrier - must be called
*
* For C code use the inline version named instruction_hazard().
*/
LEAF(mips_ihb)
.set mips32r2
jr.hb ra
nop
END(mips_ihb)
#endif /* CONFIG_CPU_MIPSR2 or CONFIG_MIPS_MT */
