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Diffstat (limited to 'arch/blackfin/lib/memset.S')
-rw-r--r-- | arch/blackfin/lib/memset.S | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/arch/blackfin/lib/memset.S b/arch/blackfin/lib/memset.S new file mode 100644 index 000000000000..ba6d047568dd --- /dev/null +++ b/arch/blackfin/lib/memset.S | |||
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1 | /* | ||
2 | * File: arch/blackfin/lib/memset.S | ||
3 | * Based on: | ||
4 | * Author: | ||
5 | * | ||
6 | * Created: | ||
7 | * Description: | ||
8 | * | ||
9 | * Modified: | ||
10 | * Copyright 2004-2006 Analog Devices Inc. | ||
11 | * | ||
12 | * Bugs: Enter bugs at http://blackfin.uclinux.org/ | ||
13 | * | ||
14 | * This program is free software; you can redistribute it and/or modify | ||
15 | * it under the terms of the GNU General Public License as published by | ||
16 | * the Free Software Foundation; either version 2 of the License, or | ||
17 | * (at your option) any later version. | ||
18 | * | ||
19 | * This program is distributed in the hope that it will be useful, | ||
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
22 | * GNU General Public License for more details. | ||
23 | * | ||
24 | * You should have received a copy of the GNU General Public License | ||
25 | * along with this program; if not, see the file COPYING, or write | ||
26 | * to the Free Software Foundation, Inc., | ||
27 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | ||
28 | */ | ||
29 | |||
30 | #include <linux/linkage.h> | ||
31 | |||
32 | .align 2 | ||
33 | |||
34 | #ifdef CONFIG_MEMSET_L1 | ||
35 | .section .l1.text | ||
36 | #else | ||
37 | .text | ||
38 | #endif | ||
39 | |||
40 | /* | ||
41 | * C Library function MEMSET | ||
42 | * R0 = address (leave unchanged to form result) | ||
43 | * R1 = filler byte | ||
44 | * R2 = count | ||
45 | * Favours word aligned data. | ||
46 | */ | ||
47 | |||
48 | ENTRY(_memset) | ||
49 | P0 = R0 ; /* P0 = address */ | ||
50 | P2 = R2 ; /* P2 = count */ | ||
51 | R3 = R0 + R2; /* end */ | ||
52 | CC = R2 <= 7(IU); | ||
53 | IF CC JUMP .Ltoo_small; | ||
54 | R1 = R1.B (Z); /* R1 = fill char */ | ||
55 | R2 = 3; | ||
56 | R2 = R0 & R2; /* addr bottom two bits */ | ||
57 | CC = R2 == 0; /* AZ set if zero. */ | ||
58 | IF !CC JUMP .Lforce_align ; /* Jump if addr not aligned. */ | ||
59 | |||
60 | .Laligned: | ||
61 | P1 = P2 >> 2; /* count = n/4 */ | ||
62 | R2 = R1 << 8; /* create quad filler */ | ||
63 | R2.L = R2.L + R1.L(NS); | ||
64 | R2.H = R2.L + R1.H(NS); | ||
65 | P2 = R3; | ||
66 | |||
67 | LSETUP (.Lquad_loop , .Lquad_loop) LC0=P1; | ||
68 | .Lquad_loop: | ||
69 | [P0++] = R2; | ||
70 | |||
71 | CC = P0 == P2; | ||
72 | IF !CC JUMP .Lbytes_left; | ||
73 | RTS; | ||
74 | |||
75 | .Lbytes_left: | ||
76 | R2 = R3; /* end point */ | ||
77 | R3 = P0; /* current position */ | ||
78 | R2 = R2 - R3; /* bytes left */ | ||
79 | P2 = R2; | ||
80 | |||
81 | .Ltoo_small: | ||
82 | CC = P2 == 0; /* Check zero count */ | ||
83 | IF CC JUMP .Lfinished; /* Unusual */ | ||
84 | |||
85 | .Lbytes: | ||
86 | LSETUP (.Lbyte_loop , .Lbyte_loop) LC0=P2; | ||
87 | .Lbyte_loop: | ||
88 | B[P0++] = R1; | ||
89 | |||
90 | .Lfinished: | ||
91 | RTS; | ||
92 | |||
93 | .Lforce_align: | ||
94 | CC = BITTST (R0, 0); /* odd byte */ | ||
95 | R0 = 4; | ||
96 | R0 = R0 - R2; | ||
97 | P1 = R0; | ||
98 | R0 = P0; /* Recover return address */ | ||
99 | IF !CC JUMP .Lskip1; | ||
100 | B[P0++] = R1; | ||
101 | .Lskip1: | ||
102 | CC = R2 <= 2; /* 2 bytes */ | ||
103 | P2 -= P1; /* reduce count */ | ||
104 | IF !CC JUMP .Laligned; | ||
105 | B[P0++] = R1; | ||
106 | B[P0++] = R1; | ||
107 | JUMP .Laligned; | ||
108 | |||
109 | .size _memset,.-_memset | ||