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Diffstat (limited to 'firmware/bitswap.S')
-rw-r--r-- | firmware/bitswap.S | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/firmware/bitswap.S b/firmware/bitswap.S new file mode 100644 index 0000000000..5f94fedb36 --- /dev/null +++ b/firmware/bitswap.S | |||
@@ -0,0 +1,101 @@ | |||
1 | /*************************************************************************** | ||
2 | * __________ __ ___. | ||
3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
7 | * \/ \/ \/ \/ \/ | ||
8 | * $Id$ | ||
9 | * | ||
10 | * Copyright (C) 2002 by Magnus Holmgren | ||
11 | * | ||
12 | * All files in this archive are subject to the GNU General Public License. | ||
13 | * See the file COPYING in the source tree root for full license agreement. | ||
14 | * | ||
15 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
16 | * KIND, either express or implied. | ||
17 | * | ||
18 | ****************************************************************************/ | ||
19 | |||
20 | .section .icode,"ax",@progbits | ||
21 | .global _bitswap | ||
22 | .align 4 | ||
23 | .type _bitswap,@function | ||
24 | |||
25 | /* Registers used: | ||
26 | * | ||
27 | * r0 Temporary (required by some instructions) | ||
28 | * r1 Low byte | ||
29 | * r2 High byte | ||
30 | * r3 Result after flip | ||
31 | * r4 Data | ||
32 | * r5 Length | ||
33 | * r6 Current (position in Data) | ||
34 | * r7 Flip table | ||
35 | */ | ||
36 | |||
37 | _bitswap: | ||
38 | mov.l .fliptable,r7 | ||
39 | mov r4,r6 | ||
40 | add r5,r6 /* goto end of buffer */ | ||
41 | add r5,r6 /* (direction IS important) */ | ||
42 | bra .init | ||
43 | .loop: | ||
44 | mov.w @r4,r1 /* data to flip */ | ||
45 | swap.b r1,r2 | ||
46 | extu.b r2,r0 /* high byte */ | ||
47 | mov.b @(r0,r7),r2 | ||
48 | extu.b r2,r0 /* remove any sign extend */ | ||
49 | swap.b r0,r3 /* put high byte in result */ | ||
50 | extu.b r1,r0 /* low byte */ | ||
51 | mov.b @(r0,r7),r1 | ||
52 | extu.b r1,r0 /* remove any sign extend */ | ||
53 | or r0,r3 /* put low byte in result */ | ||
54 | mov.w r3,@r4 /* store result */ | ||
55 | add #2,r4 | ||
56 | .init: | ||
57 | cmp/gt r4,r6 /* while (data < start+length*2) */ | ||
58 | bt .loop | ||
59 | rts | ||
60 | |||
61 | .align 4 | ||
62 | |||
63 | .fliptable: | ||
64 | .long _fliptable | ||
65 | |||
66 | _fliptable: | ||
67 | .byte 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0 | ||
68 | .byte 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0 | ||
69 | .byte 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8 | ||
70 | .byte 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8 | ||
71 | .byte 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4 | ||
72 | .byte 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4 | ||
73 | .byte 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec | ||
74 | .byte 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc | ||
75 | .byte 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2 | ||
76 | .byte 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2 | ||
77 | .byte 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea | ||
78 | .byte 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa | ||
79 | .byte 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6 | ||
80 | .byte 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6 | ||
81 | .byte 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee | ||
82 | .byte 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe | ||
83 | .byte 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1 | ||
84 | .byte 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1 | ||
85 | .byte 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9 | ||
86 | .byte 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9 | ||
87 | .byte 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5 | ||
88 | .byte 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5 | ||
89 | .byte 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed | ||
90 | .byte 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd | ||
91 | .byte 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3 | ||
92 | .byte 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3 | ||
93 | .byte 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb | ||
94 | .byte 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb | ||
95 | .byte 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7 | ||
96 | .byte 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7 | ||
97 | .byte 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef | ||
98 | .byte 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff | ||
99 | |||
100 | .end: | ||
101 | .size _bitswap,.end-_bitswap | ||