/* * File      : context.S * This file is part of RT-Thread RTOS * COPYRIGHT (C) 2006, RT-Thread Development Team * * The license and distribution terms for this file may be * found in the file LICENSE in this distribution or at * http://openlab.rt-thread.com/license/LICENSE * * Change Logs: * Date           Author       Notes * 2006-09-15     QiuYi        The first version * 2006-10-09     Bernard      add rt_hw_context_switch_to implementation */ /** * @addtogroup ia32 *//*@{*//* * void rt_hw_context_switch(rt_uint32 from, rt_uint32 to); */.globl rt_hw_context_switchrt_hw_context_switch:	pushfl					/*pushed eflags*/	push %cs				/*push cs register*/	pushl 0x8(%esp)			/*pushed eip register*/	pushl $0				/*fill irqno*/	push %ds				/*push ds register*/	push %es				/*push es register*/	pushal					/*push eax,ecx,edx,ebx,esp,ebp,esp,edi registers*/		movl 0x40(%esp), %eax	/*to thread TCB*/	movl 0x3c(%esp), %ebx	/*from thread TCB*/	movl %esp, (%ebx)		/*store esp in preempted tasks TCB*/	movl (%eax), %esp		/*get new task stack pointer*/	popal					/*restore new task TCB*/	pop %es	pop %ds	add $4,%esp				/*skip irqno*/	iret/* * void rt_hw_context_switch_to(rt_uint32 to); */.globl rt_hw_context_switch_tort_hw_context_switch_to:	push %ebp	movl %esp, %ebp	movl 0x8(%ebp), %eax	/* to thread TCB */	movl (%eax), %esp		/* get new task stack pointer */	popal					/* restore new task TCB*/	pop %es	pop %ds	add $4, %esp			/* skip irqno */	iret/* * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to); */.globl rt_thread_switch_interrput_flag.globl rt_interrupt_from_thread.globl rt_interrupt_to_thread.globl rt_hw_context_switch_interruptrt_hw_context_switch_interrupt:	pushl %ebp	movl %esp, %ebp	movl 0xc(%ebp), %eax	movl 0x8(%ebp), %ebx		movl $rt_thread_switch_interrput_flag, %ecx	movl (%ecx), %edx	cmp $0x1, %edx	jz _reswitch		movl $0x1, %edx				/*set rt_thread_switch_interrput_flag to 1*/	movl %edx, (%ecx)	movl $rt_interrupt_from_thread, %edx	/*set rt_interrupt_from_thread*/	movl %ebx, (%edx)_reswitch:	movl $rt_interrupt_to_thread, %edx		/*set rt_interrupt_to_thread*/	movl %eax, (%edx)	leave	ret