52 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			52 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * This file is subject to the terms and conditions of the GNU General Public | ||
|  |  * License.  See the file "COPYING" in the main directory of this archive | ||
|  |  * for more details. | ||
|  |  * | ||
|  |  * Copyright (C) 2001  Hiroyuki Kondo, Hirokazu Takata, and Hitoshi Yamamoto | ||
|  |  * Copyright (C) 2004, 2006  Hirokazu Takata <takata at linux-m32r.org> | ||
|  |  */ | ||
|  | #ifndef _ASM_M32R_SWITCH_TO_H
 | ||
|  | #define _ASM_M32R_SWITCH_TO_H
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * switch_to(prev, next) should switch from task `prev' to `next' | ||
|  |  * `prev' will never be the same as `next'. | ||
|  |  * | ||
|  |  * `next' and `prev' should be struct task_struct, but it isn't always defined | ||
|  |  */ | ||
|  | 
 | ||
|  | #if defined(CONFIG_FRAME_POINTER) || \
 | ||
|  | 	!defined(CONFIG_SCHED_OMIT_FRAME_POINTER) | ||
|  | #define M32R_PUSH_FP "	push fp\n"
 | ||
|  | #define M32R_POP_FP  "	pop  fp\n"
 | ||
|  | #else
 | ||
|  | #define M32R_PUSH_FP ""
 | ||
|  | #define M32R_POP_FP  ""
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #define switch_to(prev, next, last)  do { \
 | ||
|  | 	__asm__ __volatile__ ( \ | ||
|  | 		"	seth	lr, #high(1f)				\n" \ | ||
|  | 		"	or3	lr, lr, #low(1f)			\n" \ | ||
|  | 		"	st	lr, @%4  ; store old LR			\n" \ | ||
|  | 		"	ld	lr, @%5  ; load new LR			\n" \ | ||
|  | 			M32R_PUSH_FP \ | ||
|  | 		"	st	sp, @%2  ; store old SP			\n" \ | ||
|  | 		"	ld	sp, @%3  ; load new SP			\n" \ | ||
|  | 		"	push	%1  ; store `prev' on new stack		\n" \ | ||
|  | 		"	jmp	lr					\n" \ | ||
|  | 		"	.fillinsn					\n" \ | ||
|  | 		"1:							\n" \ | ||
|  | 		"	pop	%0  ; restore `__last' from new stack	\n" \ | ||
|  | 			M32R_POP_FP \ | ||
|  | 		: "=r" (last) \ | ||
|  | 		: "0" (prev), \ | ||
|  | 		  "r" (&(prev->thread.sp)), "r" (&(next->thread.sp)), \ | ||
|  | 		  "r" (&(prev->thread.lr)), "r" (&(next->thread.lr)) \ | ||
|  | 		: "memory", "lr" \ | ||
|  | 	); \ | ||
|  | } while(0) | ||
|  | 
 | ||
|  | #endif /* _ASM_M32R_SWITCH_TO_H */
 |