projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 322ae8eb MS |
1 | /* |
| 2 | * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> | |
| 3 | * Copyright (C) 2008-2009 PetaLogix | |
| 4 | * Copyright (C) 2007 John Williams | |
| 5 | * | |
| 6 | * Reasonably optimised generic C-code for memset on Microblaze | |
| 7 | * This is generic C code to do efficient, alignment-aware memcpy. | |
| 8 | * | |
| 9 | * It is based on demo code originally Copyright 2001 by Intel Corp, taken from | |
| 10 | * http://www.embedded.com/showArticle.jhtml?articleID=19205567 | |
| 11 | * | |
| af901ca1 | 12 | * Attempts were made, unsuccessfully, to contact the original |
| 322ae8eb MS |
13 | * author of this code (Michael Morrow, Intel). Below is the original |
| 14 | * copyright notice. | |
| 15 | * | |
| 16 | * This software has been developed by Intel Corporation. | |
| 17 | * Intel specifically disclaims all warranties, express or | |
| 18 | * implied, and all liability, including consequential and | |
| 19 | * other indirect damages, for the use of this program, including | |
| 20 | * liability for infringement of any proprietary rights, | |
| 21 | * and including the warranties of merchantability and fitness | |
| 22 | * for a particular purpose. Intel does not assume any | |
| 23 | * responsibility for and errors which may appear in this program | |
| 24 | * not any responsibility to update it. | |
| 25 | */ | |
| 26 | ||
| 27 | #include <linux/types.h> | |
| 28 | #include <linux/stddef.h> | |
| 29 | #include <linux/compiler.h> | |
| 30 | #include <linux/module.h> | |
| 31 | #include <linux/string.h> | |
| 32 | ||
| 33 | #ifdef __HAVE_ARCH_MEMSET | |
| 34 | void *memset(void *v_src, int c, __kernel_size_t n) | |
| 35 | { | |
| 322ae8eb MS |
36 | char *src = v_src; |
| 37 | #ifdef CONFIG_OPT_LIB_FUNCTION | |
| 38 | uint32_t *i_src; | |
| 78ebfa88 | 39 | uint32_t w32 = 0; |
| 322ae8eb MS |
40 | #endif |
| 41 | /* Truncate c to 8 bits */ | |
| 42 | c = (c & 0xFF); | |
| 43 | ||
| 44 | #ifdef CONFIG_OPT_LIB_FUNCTION | |
| 78ebfa88 MS |
45 | if (unlikely(c)) { |
| 46 | /* Make a repeating word out of it */ | |
| 47 | w32 = c; | |
| 48 | w32 |= w32 << 8; | |
| 49 | w32 |= w32 << 16; | |
| 50 | } | |
| 322ae8eb | 51 | |
| 78ebfa88 | 52 | if (likely(n >= 4)) { |
| 322ae8eb MS |
53 | /* Align the destination to a word boundary */ |
| 54 | /* This is done in an endian independant manner */ | |
| 55 | switch ((unsigned) src & 3) { | |
| 56 | case 1: | |
| 57 | *src++ = c; | |
| 58 | --n; | |
| 59 | case 2: | |
| 60 | *src++ = c; | |
| 61 | --n; | |
| 62 | case 3: | |
| 63 | *src++ = c; | |
| 64 | --n; | |
| 65 | } | |
| 66 | ||
| 67 | i_src = (void *)src; | |
| 68 | ||
| 69 | /* Do as many full-word copies as we can */ | |
| 70 | for (; n >= 4; n -= 4) | |
| 71 | *i_src++ = w32; | |
| 72 | ||
| 73 | src = (void *)i_src; | |
| 74 | } | |
| 75 | #endif | |
| 76 | /* Simple, byte oriented memset or the rest of count. */ | |
| 77 | while (n--) | |
| 78 | *src++ = c; | |
| 79 | ||
| 80 | return v_src; | |
| 81 | } | |
| 82 | EXPORT_SYMBOL(memset); | |
| 83 | #endif /* __HAVE_ARCH_MEMSET */ |