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Diffstat (limited to 'utils/hwstub/stmp/memset.S')
| -rw-r--r-- | utils/hwstub/stmp/memset.S | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/utils/hwstub/stmp/memset.S b/utils/hwstub/stmp/memset.S new file mode 100644 index 0000000000..682da874ce --- /dev/null +++ b/utils/hwstub/stmp/memset.S | |||
| @@ -0,0 +1,98 @@ | |||
| 1 | /*************************************************************************** | ||
| 2 | * __________ __ ___. | ||
| 3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
| 4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
| 5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
| 6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
| 7 | * \/ \/ \/ \/ \/ | ||
| 8 | * $Id$ | ||
| 9 | * | ||
| 10 | * Copyright (C) 2006 by Thom Johansen | ||
| 11 | * | ||
| 12 | * This program is free software; you can redistribute it and/or | ||
| 13 | * modify it under the terms of the GNU General Public License | ||
| 14 | * as published by the Free Software Foundation; either version 2 | ||
| 15 | * of the License, or (at your option) any later version. | ||
| 16 | * | ||
| 17 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
| 18 | * KIND, either express or implied. | ||
| 19 | * | ||
| 20 | ****************************************************************************/ | ||
| 21 | #include "config.h" | ||
| 22 | |||
| 23 | .section .icode,"ax",%progbits | ||
| 24 | |||
| 25 | .align 2 | ||
| 26 | |||
| 27 | /* The following code is based on code found in Linux kernel version 2.6.15.3 | ||
| 28 | * linux/arch/arm/lib/memset.S | ||
| 29 | * | ||
| 30 | * Copyright (C) 1995-2000 Russell King | ||
| 31 | */ | ||
| 32 | |||
| 33 | /* This code will align a pointer for memset, if needed */ | ||
| 34 | 1: cmp r2, #4 @ 1 do we have enough | ||
| 35 | blt 5f @ 1 bytes to align with? | ||
| 36 | cmp r3, #2 @ 1 | ||
| 37 | strgtb r1, [r0, #-1]! @ 1 | ||
| 38 | strgeb r1, [r0, #-1]! @ 1 | ||
| 39 | strb r1, [r0, #-1]! @ 1 | ||
| 40 | sub r2, r2, r3 @ 1 r2 = r2 - r3 | ||
| 41 | b 2f | ||
| 42 | |||
| 43 | .global memset | ||
| 44 | .type memset,%function | ||
| 45 | memset: | ||
| 46 | add r0, r0, r2 @ we'll write backwards in memory | ||
| 47 | ands r3, r0, #3 @ 1 unaligned? | ||
| 48 | bne 1b @ 1 | ||
| 49 | 2: | ||
| 50 | /* | ||
| 51 | * we know that the pointer in r0 is aligned to a word boundary. | ||
| 52 | */ | ||
| 53 | orr r1, r1, r1, lsl #8 | ||
| 54 | orr r1, r1, r1, lsl #16 | ||
| 55 | mov r3, r1 | ||
| 56 | cmp r2, #16 | ||
| 57 | blt 5f | ||
| 58 | /* | ||
| 59 | * We need an extra register for this loop - save the return address and | ||
| 60 | * use the LR | ||
| 61 | */ | ||
| 62 | str lr, [sp, #-4]! | ||
| 63 | mov ip, r1 | ||
| 64 | mov lr, r1 | ||
| 65 | |||
| 66 | 3: subs r2, r2, #64 | ||
| 67 | stmgedb r0!, {r1, r3, ip, lr} @ 64 bytes at a time. | ||
| 68 | stmgedb r0!, {r1, r3, ip, lr} | ||
| 69 | stmgedb r0!, {r1, r3, ip, lr} | ||
| 70 | stmgedb r0!, {r1, r3, ip, lr} | ||
| 71 | bgt 3b | ||
| 72 | ldrpc cond=eq @ Now <64 bytes to go. | ||
| 73 | /* | ||
| 74 | * No need to correct the count; we're only testing bits from now on | ||
| 75 | */ | ||
| 76 | tst r2, #32 | ||
| 77 | stmnedb r0!, {r1, r3, ip, lr} | ||
| 78 | stmnedb r0!, {r1, r3, ip, lr} | ||
| 79 | tst r2, #16 | ||
| 80 | stmnedb r0!, {r1, r3, ip, lr} | ||
| 81 | ldr lr, [sp], #4 | ||
| 82 | |||
| 83 | 5: tst r2, #8 | ||
| 84 | stmnedb r0!, {r1, r3} | ||
| 85 | tst r2, #4 | ||
| 86 | strne r1, [r0, #-4]! | ||
| 87 | /* | ||
| 88 | * When we get here, we've got less than 4 bytes to zero. We | ||
| 89 | * may have an unaligned pointer as well. | ||
| 90 | */ | ||
| 91 | 6: tst r2, #2 | ||
| 92 | strneb r1, [r0, #-1]! | ||
| 93 | strneb r1, [r0, #-1]! | ||
| 94 | tst r2, #1 | ||
| 95 | strneb r1, [r0, #-1]! | ||
| 96 | bx lr | ||
| 97 | .end: | ||
| 98 | .size memset,.end-memset | ||