173 lines
5.0 KiB
ArmAsm
173 lines
5.0 KiB
ArmAsm
|
/*
|
||
|
|
* File : context.S
|
||
|
|
* This file is part of RT-Thread RTOS
|
||
|
|
* COPYRIGHT (C) 2013, RT-Thread Development Team
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU General Public License as published by
|
||
|
|
* the Free Software Foundation; either version 2 of the License, or
|
||
|
|
* (at your option) any later version.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
* GNU General Public License for more details.
|
||
|
|
*
|
||
|
|
* You should have received a copy of the GNU General Public License along
|
||
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
||
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
||
|
|
*
|
||
|
|
* Change Logs:
|
||
|
|
* Date Author Notes
|
||
|
|
* 2013-07-05 Bernard the first version
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <rtconfig.h>
|
||
|
|
|
||
|
|
#ifdef RT_USING_VMM
|
||
|
|
#include <vmm.h>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
.section .text, "ax"
|
||
|
|
/*
|
||
|
|
* rt_base_t rt_hw_interrupt_disable();
|
||
|
|
*/
|
||
|
|
.globl rt_hw_interrupt_disable
|
||
|
|
rt_hw_interrupt_disable:
|
||
|
|
mrs r0, cpsr
|
||
|
|
cpsid i
|
||
|
|
bx lr
|
||
|
|
|
||
|
|
/*
|
||
|
|
* void rt_hw_interrupt_enable(rt_base_t level);
|
||
|
|
*/
|
||
|
|
.globl rt_hw_interrupt_enable
|
||
|
|
rt_hw_interrupt_enable:
|
||
|
|
msr cpsr, r0
|
||
|
|
bx lr
|
||
|
|
|
||
|
|
/*
|
||
|
|
* void rt_hw_context_switch_to(rt_uint32 to);
|
||
|
|
* r0 --> to
|
||
|
|
*/
|
||
|
|
.globl rt_hw_context_switch_to
|
||
|
|
rt_hw_context_switch_to:
|
||
|
|
ldr sp, [r0] @ get new task stack pointer
|
||
|
|
|
||
|
|
ldmfd sp!, {r4} @ pop new task spsr
|
||
|
|
msr spsr_cxsf, r4
|
||
|
|
|
||
|
|
ldmfd sp!, {r0-r12, lr, pc}^ @ pop new task r0-r12, lr & pc
|
||
|
|
|
||
|
|
.section .bss.share.isr
|
||
|
|
_guest_switch_lvl:
|
||
|
|
.word 0
|
||
|
|
|
||
|
|
.globl vmm_virq_update
|
||
|
|
|
||
|
|
.section .text.isr, "ax"
|
||
|
|
/*
|
||
|
|
* void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
|
||
|
|
* r0 --> from
|
||
|
|
* r1 --> to
|
||
|
|
*/
|
||
|
|
.globl rt_hw_context_switch
|
||
|
|
rt_hw_context_switch:
|
||
|
|
stmfd sp!, {lr} @ push pc (lr should be pushed in place of PC)
|
||
|
|
stmfd sp!, {r0-r12, lr} @ push lr & register file
|
||
|
|
|
||
|
|
mrs r4, cpsr
|
||
|
|
tst lr, #0x01
|
||
|
|
orrne r4, r4, #0x20 @ it's thumb code
|
||
|
|
|
||
|
|
stmfd sp!, {r4} @ push cpsr
|
||
|
|
|
||
|
|
str sp, [r0] @ store sp in preempted tasks TCB
|
||
|
|
ldr sp, [r1] @ get new task stack pointer
|
||
|
|
|
||
|
|
#ifdef RT_USING_VMM
|
||
|
|
#ifdef RT_VMM_USING_DOMAIN
|
||
|
|
@ need to make sure we are in vmm domain as we would use rt_current_thread
|
||
|
|
ldr r2, =vmm_domain_val
|
||
|
|
ldr r7, [r2]
|
||
|
|
mcr p15, 0, r7, c3, c0
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* check whether vmm thread, otherwise, update vIRQ */
|
||
|
|
ldr r3, =rt_current_thread
|
||
|
|
ldr r4, [r3]
|
||
|
|
ldr r5, =vmm_thread
|
||
|
|
cmp r4, r5
|
||
|
|
beq switch_to_guest
|
||
|
|
|
||
|
|
@ not falling into guest. Simple task ;-)
|
||
|
|
ldmfd sp!, {r6} @ pop new task cpsr to spsr
|
||
|
|
msr spsr_cxsf, r6
|
||
|
|
ldmfd sp!, {r0-r12, lr, pc}^
|
||
|
|
|
||
|
|
switch_to_guest:
|
||
|
|
#ifdef RT_VMM_USING_DOMAIN
|
||
|
|
@ the stack is saved in the guest domain so we need to
|
||
|
|
@ come back to the guest domain to get the registers.
|
||
|
|
ldr r1, =super_domain_val
|
||
|
|
ldr r0, [r1]
|
||
|
|
mcr p15, 0, r0, c3, c0
|
||
|
|
#endif
|
||
|
|
/* The user can do nearly anything in rt_thread_idle_excute because it will
|
||
|
|
call the thread->cleanup. One common thing is sending events and wake up
|
||
|
|
threads. So the guest thread will be preempted. This is the only point that
|
||
|
|
the guest thread would call rt_hw_context_switch and "yield".
|
||
|
|
|
||
|
|
More over, rt_schedule will call this function and this function *will*
|
||
|
|
reentrant. If that happens, we need to make sure that call the
|
||
|
|
rt_thread_idle_excute and vmm_virq_update again and we are in super domain.
|
||
|
|
I use a "reference count" to achieve such behaviour. If you have better
|
||
|
|
idea, tell me. */
|
||
|
|
ldr r4, =_guest_switch_lvl
|
||
|
|
ldr r5, [r4]
|
||
|
|
add r5, r5, #1
|
||
|
|
str r5, [r4]
|
||
|
|
cmp r5, #1
|
||
|
|
bne _switch_through
|
||
|
|
|
||
|
|
bl rt_thread_idle_excute
|
||
|
|
bl vmm_virq_update
|
||
|
|
|
||
|
|
/* we need _guest_switch_lvl to protect until _switch_through, but it's OK
|
||
|
|
* to cleanup the reference count here because the code below will not be
|
||
|
|
* reentrant. */
|
||
|
|
sub r5, r5, #1
|
||
|
|
str r5, [r4]
|
||
|
|
|
||
|
|
#ifdef RT_VMM_USING_DOMAIN
|
||
|
|
ldr r1, =guest_domain_val
|
||
|
|
ldr r0, [r1]
|
||
|
|
mcr p15, 0, r0, c3, c0
|
||
|
|
#endif
|
||
|
|
_switch_through:
|
||
|
|
#endif /* RT_USING_VMM */
|
||
|
|
ldmfd sp!, {r4} @ pop new task cpsr to spsr
|
||
|
|
msr spsr_cxsf, r4
|
||
|
|
ldmfd sp!, {r0-r12, lr, pc}^ @ pop new task r0-r12, lr & pc, copy spsr to cpsr
|
||
|
|
|
||
|
|
/*
|
||
|
|
* 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:
|
||
|
|
ldr r2, =rt_thread_switch_interrupt_flag
|
||
|
|
ldr r3, [r2]
|
||
|
|
cmp r3, #1
|
||
|
|
beq _reswitch
|
||
|
|
ldr ip, =rt_interrupt_from_thread @ set rt_interrupt_from_thread
|
||
|
|
mov r3, #1 @ set rt_thread_switch_interrupt_flag to 1
|
||
|
|
str r0, [ip]
|
||
|
|
str r3, [r2]
|
||
|
|
_reswitch:
|
||
|
|
ldr r2, =rt_interrupt_to_thread @ set rt_interrupt_to_thread
|
||
|
|
str r1, [r2]
|
||
|
|
bx lr
|