48 lines
		
	
	
		
			1010 B
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			48 lines
		
	
	
		
			1010 B
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Copyright (C) 2020 Embecosm Limited
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|  * SPDX-License-Identifier: BSD-2-Clause
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|  */
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| #ifndef _INTERNAL_SYSCALL_H
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| #define _INTERNAL_SYSCALL_H
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| 
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| extern int errno;
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| 
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| static inline long
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| __semihost_syscall (long id, long *data_block)
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| {
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|   register long a0 asm ("a0") = id;
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|   register long a1 asm ("a1") = (long) data_block;
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| 
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|   /* RISC-V semihosting trap sequence.  Must be uncompressed and must not
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|      cross page boundary.  */
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|   asm volatile (
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|     ".balign 16             \n"
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|     ".option push           \n"
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|     ".option norvc          \n"
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|     "slli zero, zero, 0x1f  \n"
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|     "ebreak                 \n"
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|     "srai zero, zero, 0x7   \n"
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|     ".option pop            \n"
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|       : "+r"(a0) : "r"(a1) : "memory");
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| 
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|   return a0;
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| }
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| 
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| static inline long
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| __syscall_error ()
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| {
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|   errno = __semihost_syscall (SEMIHOST_errno, 0);
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|   return -1;
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| }
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| 
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| static inline long
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| syscall_errno (long id, long *data_block)
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| {
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|   long res = __semihost_syscall (id, data_block);
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|   if (res < 0)
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|     return __syscall_error ();
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|   return res;
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| }
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| 
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| #endif
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