95 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			95 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
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|  * Copyright (C) 2008-2009 PetaLogix
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|  * Copyright (C) 2007 John Williams
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|  *
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|  * Reasonably optimised generic C-code for memset on Microblaze
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|  * This is generic C code to do efficient, alignment-aware memcpy.
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|  *
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|  * It is based on demo code originally Copyright 2001 by Intel Corp, taken from
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|  * http://www.embedded.com/showArticle.jhtml?articleID=19205567
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|  *
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|  * Attempts were made, unsuccessfully, to contact the original
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|  * author of this code (Michael Morrow, Intel).  Below is the original
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|  * copyright notice.
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|  *
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|  * This software has been developed by Intel Corporation.
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|  * Intel specifically disclaims all warranties, express or
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|  * implied, and all liability, including consequential and
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|  * other indirect damages, for the use of this program, including
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|  * liability for infringement of any proprietary rights,
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|  * and including the warranties of merchantability and fitness
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|  * for a particular purpose. Intel does not assume any
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|  * responsibility for and errors which may appear in this program
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|  * not any responsibility to update it.
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|  */
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| 
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| #include <linux/export.h>
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| #include <linux/types.h>
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| #include <linux/stddef.h>
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| #include <linux/compiler.h>
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| #include <linux/string.h>
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| 
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| #ifdef CONFIG_OPT_LIB_FUNCTION
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| void *memset(void *v_src, int c, __kernel_size_t n)
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| {
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| 	char *src = v_src;
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| 	uint32_t *i_src;
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| 	uint32_t w32 = 0;
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| 
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| 	/* Truncate c to 8 bits */
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| 	c = (c & 0xFF);
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| 
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| 	if (unlikely(c)) {
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| 		/* Make a repeating word out of it */
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| 		w32 = c;
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| 		w32 |= w32 << 8;
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| 		w32 |= w32 << 16;
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| 	}
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| 
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| 	if (likely(n >= 4)) {
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| 		/* Align the destination to a word boundary */
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| 		/* This is done in an endian independent manner */
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| 		switch ((unsigned) src & 3) {
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| 		case 1:
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| 			*src++ = c;
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| 			--n;
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| 			fallthrough;
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| 		case 2:
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| 			*src++ = c;
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| 			--n;
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| 			fallthrough;
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| 		case 3:
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| 			*src++ = c;
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| 			--n;
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| 		}
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| 
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| 		i_src  = (void *)src;
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| 
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| 		/* Do as many full-word copies as we can */
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| 		for (; n >= 4; n -= 4)
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| 			*i_src++ = w32;
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| 
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| 		src  = (void *)i_src;
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| 	}
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| 
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| 	/* Simple, byte oriented memset or the rest of count. */
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| 	switch (n) {
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| 	case 3:
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| 		*src++ = c;
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| 		fallthrough;
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| 	case 2:
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| 		*src++ = c;
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| 		fallthrough;
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| 	case 1:
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| 		*src++ = c;
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| 		break;
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| 	default:
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| 		break;
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| 	}
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| 
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| 	return v_src;
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| }
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| EXPORT_SYMBOL(memset);
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| #endif /* CONFIG_OPT_LIB_FUNCTION */
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