| Michal Simek | 322ae8e | 2009-03-27 14:25:21 +0100 | [diff] [blame^] | 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 | * |
| 12 | * Attempts were made, unsuccesfully, to contact the original |
| 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 | { |
| 36 | |
| 37 | char *src = v_src; |
| 38 | #ifdef CONFIG_OPT_LIB_FUNCTION |
| 39 | uint32_t *i_src; |
| 40 | uint32_t w32; |
| 41 | #endif |
| 42 | /* Truncate c to 8 bits */ |
| 43 | c = (c & 0xFF); |
| 44 | |
| 45 | #ifdef CONFIG_OPT_LIB_FUNCTION |
| 46 | /* Make a repeating word out of it */ |
| 47 | w32 = c; |
| 48 | w32 |= w32 << 8; |
| 49 | w32 |= w32 << 16; |
| 50 | |
| 51 | if (n >= 4) { |
| 52 | /* Align the destination to a word boundary */ |
| 53 | /* This is done in an endian independant manner */ |
| 54 | switch ((unsigned) src & 3) { |
| 55 | case 1: |
| 56 | *src++ = c; |
| 57 | --n; |
| 58 | case 2: |
| 59 | *src++ = c; |
| 60 | --n; |
| 61 | case 3: |
| 62 | *src++ = c; |
| 63 | --n; |
| 64 | } |
| 65 | |
| 66 | i_src = (void *)src; |
| 67 | |
| 68 | /* Do as many full-word copies as we can */ |
| 69 | for (; n >= 4; n -= 4) |
| 70 | *i_src++ = w32; |
| 71 | |
| 72 | src = (void *)i_src; |
| 73 | } |
| 74 | #endif |
| 75 | /* Simple, byte oriented memset or the rest of count. */ |
| 76 | while (n--) |
| 77 | *src++ = c; |
| 78 | |
| 79 | return v_src; |
| 80 | } |
| 81 | EXPORT_SYMBOL(memset); |
| 82 | #endif /* __HAVE_ARCH_MEMSET */ |