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/*
* File : context_gcc.S
* Change Logs:
* Date Author Notes
* 2010-05-17 swkyer first version
* 2010-09-11 bernard port to Jz4755
*/
#include "../common/mips.inc"
#include "../common/stackframe.h"
#include "stack.h"
.section ".text", "ax"
.set noreorder
/*
* rt_base_t rt_hw_interrupt_disable()
*/
.globl rt_hw_interrupt_disable
rt_hw_interrupt_disable:
mfc0 v0, CP0_STATUS
and v1, v0, 0xfffffffe
mtc0 v1, CP0_STATUS
jr ra
nop
/*
* void rt_hw_interrupt_enable(rt_base_t level)
*/
.globl rt_hw_interrupt_enable
rt_hw_interrupt_enable:
mtc0 a0, CP0_STATUS
jr ra
nop
/*
* void rt_hw_context_switch(rt_uint32 from, rt_uint32 to)
* a0 --> from
* a1 --> to
*/
.globl rt_hw_context_switch
rt_hw_context_switch:
mtc0 ra, CP0_EPC
SAVE_ALL
sw sp, 0(a0) /* store sp in preempted tasks TCB */
lw sp, 0(a1) /* get new task stack pointer */
RESTORE_ALL_AND_RET
/*
* void rt_hw_context_switch_to(rt_uint32 to)/*
* a0 --> to
*/
.globl rt_hw_context_switch_to
rt_hw_context_switch_to:
lw sp, 0(a0) /* get new task stack pointer */
RESTORE_ALL_AND_RET
/*
* void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to)/*
*/
.globl rt_thread_switch_interrupt_flag
.globl rt_interrupt_from_thread
.globl rt_interrupt_to_thread
.globl rt_hw_context_switch_interrupt
rt_hw_context_switch_interrupt:
la t0, rt_thread_switch_interrupt_flag
lw t1, 0(t0)
nop
bnez t1, _reswitch
nop
li t1, 0x01 /* set rt_thread_switch_interrupt_flag to 1 */
sw t1, 0(t0)
la t0, rt_interrupt_from_thread /* set rt_interrupt_from_thread */
sw a0, 0(t0)
_reswitch:
la t0, rt_interrupt_to_thread /* set rt_interrupt_to_thread */
sw a1, 0(t0)
jr ra
nop
.globl system_dump
/*
* void rt_hw_context_switch_interrupt_do(rt_base_t flag)
*/
.globl rt_interrupt_enter
.globl rt_interrupt_leave
.globl mips_irq_handle
mips_irq_handle:
SAVE_ALL
mfc0 t0, CP0_CAUSE
mfc0 t1, CP0_STATUS
and t0, t1
andi t0, 0xff00
beqz t0, spurious_interrupt
nop
/* let k0 keep the current context sp */
move k0, sp
/* switch to kernel stack */
li sp, SYSTEM_STACK
jal rt_interrupt_enter
nop
jal rt_interrupt_dispatch
nop
jal rt_interrupt_leave
nop
/* switch sp back to thread's context */
move sp, k0
/*
* if rt_thread_switch_interrupt_flag set, jump to
* rt_hw_context_switch_interrupt_do and don't return
*/
la k0, rt_thread_switch_interrupt_flag
lw k1, 0(k0)
beqz k1, spurious_interrupt
nop
sw zero, 0(k0) /* clear flag */
nop
/*
* switch to the new thread
*/
la k0, rt_interrupt_from_thread
lw k1, 0(k0)
nop
sw sp, 0(k1) /* store sp in preempted tasks's TCB */
la k0, rt_interrupt_to_thread
lw k1, 0(k0)
nop
lw sp, 0(k1) /* get new task's stack pointer */
j spurious_interrupt
nop
spurious_interrupt:
RESTORE_ALL_AND_RET
.set reorder
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