83 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
		
		
			
		
	
	
			83 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
|   | /* | ||
|  |  * Copyright (c) 2006-2018, RT-Thread Development Team | ||
|  |  * | ||
|  |  * SPDX-License-Identifier: Apache-2.0 | ||
|  |  * | ||
|  |  * Change Logs: | ||
|  |  * Date           Author       Notes | ||
|  |  * 2011-08-14     weety    copy from mini2440 | ||
|  |  * 2015-04-15     ArdaFu     convert from context_gcc.s | ||
|  |  */ | ||
|  | 
 | ||
|  | #define NOINT            0xc0 | ||
|  | 
 | ||
|  |     SECTION    .text:CODE(6) | ||
|  | /* | ||
|  |  * rt_base_t rt_hw_interrupt_disable();
 | ||
|  |  */ | ||
|  |     PUBLIC rt_hw_interrupt_disable | ||
|  | rt_hw_interrupt_disable: | ||
|  |     MRS     R0, CPSR | ||
|  |     ORR     R1, R0, #NOINT | ||
|  |     MSR     CPSR_C, R1 | ||
|  |     MOV     PC, LR | ||
|  | 
 | ||
|  | /* | ||
|  |  * void rt_hw_interrupt_enable(rt_base_t level);
 | ||
|  |  */ | ||
|  |     PUBLIC rt_hw_interrupt_enable | ||
|  | rt_hw_interrupt_enable: | ||
|  |     MSR     CPSR_CXSF, R0 | ||
|  |     MOV     PC, LR | ||
|  | 
 | ||
|  | /* | ||
|  |  * void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
 | ||
|  |  * r0 --> from | ||
|  |  * r1 --> to | ||
|  |  */ | ||
|  |     PUBLIC 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 | ||
|  |     STMFD   SP!, {R4}               ; push cpsr
 | ||
|  |     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!, {R0-R12, LR, PC}^  ; pop new task r0-r12, lr & pc
 | ||
|  | 
 | ||
|  | /* | ||
|  |  * void rt_hw_context_switch_to(rt_uint32 to);
 | ||
|  |  * r0 --> to | ||
|  |  */ | ||
|  |     PUBLIC 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
 | ||
|  | 
 | ||
|  | /* | ||
|  |  * 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 | ||
|  |     PUBLIC 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 | ||
|  |     MOV     R3, #1                          ; set 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] | ||
|  |     MOV     PC, LR | ||
|  |     END | ||
|  |      |