103 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
		
		
			
		
	
	
			103 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
|  | /* | ||
|  |  * Copyright (c) 2006-2018, RT-Thread Development Team | ||
|  |  * | ||
|  |  * SPDX-License-Identifier: Apache-2.0 | ||
|  |  * | ||
|  |  * Change Logs: | ||
|  |  * Date           Author       Notes | ||
|  |  * 2009-01-20     Bernard      first version | ||
|  |  */ | ||
|  | 
 | ||
|  | NOINT	EQU		0xc0	; disable interrupt in psr
 | ||
|  | 
 | ||
|  |     AREA |.text|, CODE, READONLY, ALIGN=2 | ||
|  |     ARM | ||
|  |     REQUIRE8 | ||
|  |     PRESERVE8 | ||
|  | 
 | ||
|  | ;/*
 | ||
|  | ; * rt_base_t rt_hw_interrupt_disable();
 | ||
|  | ; */
 | ||
|  | rt_hw_interrupt_disable	PROC | ||
|  |     EXPORT rt_hw_interrupt_disable | ||
|  |     MRS r0, cpsr | ||
|  |     ORR r1, r0, #NOINT | ||
|  |     MSR cpsr_c, r1 | ||
|  |     BX	lr | ||
|  |     ENDP | ||
|  | 
 | ||
|  | ;/*
 | ||
|  | ; * void rt_hw_interrupt_enable(rt_base_t level);
 | ||
|  | ; */
 | ||
|  | rt_hw_interrupt_enable	PROC | ||
|  |     EXPORT rt_hw_interrupt_enable | ||
|  |     MSR cpsr_c, r0 | ||
|  |     BX	lr | ||
|  |     ENDP | ||
|  | 
 | ||
|  | ;/*
 | ||
|  | ; * void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
 | ||
|  | ; * r0 --> from
 | ||
|  | ; * r1 --> to
 | ||
|  | ; */
 | ||
|  | rt_hw_context_switch	PROC | ||
|  |     EXPORT 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 | ||
|  |     STMFD	sp!, {r4}			; push cpsr
 | ||
|  |     MRS		r4, spsr | ||
|  |     STMFD	sp!, {r4}			; push spsr
 | ||
|  | 
 | ||
|  |     STR	sp, [r0]				; store sp in preempted tasks TCB
 | ||
|  |     LDR	sp, [r1]				; get new task stack pointer
 | ||
|  | 
 | ||
|  |     LDMFD	sp!, {r4}			; pop new task spsr
 | ||
|  |     MSR	spsr_cxsf, r4 | ||
|  |     LDMFD	sp!, {r4}			; pop new task cpsr
 | ||
|  |     MSR	cpsr_cxsf, r4 | ||
|  | 
 | ||
|  |     LDMFD	sp!, {r0-r12, lr, pc}	; pop new task r0-r12, lr & pc
 | ||
|  |     ENDP | ||
|  | 
 | ||
|  | ;/*
 | ||
|  | ; * void rt_hw_context_switch_to(rt_uint32 to);
 | ||
|  | ; * r0 --> to
 | ||
|  | ; */
 | ||
|  | rt_hw_context_switch_to	PROC | ||
|  |     EXPORT 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!, {r4}			; pop new task cpsr
 | ||
|  |     MSR	cpsr_cxsf, r4 | ||
|  | 
 | ||
|  |     LDMFD	sp!, {r0-r12, lr, pc}	; pop new task r0-r12, lr & pc
 | ||
|  |     ENDP | ||
|  | 
 | ||
|  | ;/*
 | ||
|  | ; * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to);
 | ||
|  | ; */
 | ||
|  |     IMPORT rt_thread_switch_interrupt_flag | ||
|  |     IMPORT rt_interrupt_from_thread | ||
|  |     IMPORT rt_interrupt_to_thread | ||
|  | 
 | ||
|  | rt_hw_context_switch_interrupt	PROC | ||
|  |     EXPORT rt_hw_context_switch_interrupt | ||
|  |     LDR r2, =rt_thread_switch_interrupt_flag | ||
|  |     LDR r3, [r2] | ||
|  |     CMP r3, #1 | ||
|  |     BEQ _reswitch | ||
|  |     MOV r3, #1							; set rt_thread_switch_interrupt_flag to 1
 | ||
|  |     STR r3, [r2] | ||
|  |     LDR r2, =rt_interrupt_from_thread	; set rt_interrupt_from_thread
 | ||
|  |     STR r0, [r2] | ||
|  | _reswitch | ||
|  |     LDR r2, =rt_interrupt_to_thread		; set rt_interrupt_to_thread
 | ||
|  |     STR r1, [r2] | ||
|  |     BX	lr | ||
|  |     ENDP | ||
|  | 
 | ||
|  |     END |