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Diffstat (limited to 'arch/cris/arch-v10/lib/old_checksum.c')
-rw-r--r--arch/cris/arch-v10/lib/old_checksum.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/arch/cris/arch-v10/lib/old_checksum.c b/arch/cris/arch-v10/lib/old_checksum.c
new file mode 100644
index 000000000000..22a6f0aa9cef
--- /dev/null
+++ b/arch/cris/arch-v10/lib/old_checksum.c
@@ -0,0 +1,85 @@
1/* $Id: old_checksum.c,v 1.3 2003/10/27 08:04:32 starvik Exp $
2 *
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * IP/TCP/UDP checksumming routines
8 *
9 * Authors: Jorge Cwik, <jorge@laser.satlink.net>
10 * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
11 * Tom May, <ftom@netcom.com>
12 * Lots of code moved from tcp.c and ip.c; see those files
13 * for more names.
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
19 */
20
21#include <net/checksum.h>
22#include <net/module.h>
23
24#undef PROFILE_CHECKSUM
25
26#ifdef PROFILE_CHECKSUM
27/* these are just for profiling the checksum code with an oscillioscope.. uh */
28#if 0
29#define BITOFF *((unsigned char *)0xb0000030) = 0xff
30#define BITON *((unsigned char *)0xb0000030) = 0x0
31#endif
32#include <asm/io.h>
33#define CBITON LED_ACTIVE_SET(1)
34#define CBITOFF LED_ACTIVE_SET(0)
35#define BITOFF
36#define BITON
37#else
38#define BITOFF
39#define BITON
40#define CBITOFF
41#define CBITON
42#endif
43
44/*
45 * computes a partial checksum, e.g. for TCP/UDP fragments
46 */
47
48#include <asm/delay.h>
49
50unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum)
51{
52 /*
53 * Experiments with ethernet and slip connections show that buff
54 * is aligned on either a 2-byte or 4-byte boundary.
55 */
56 const unsigned char *endMarker = buff + len;
57 const unsigned char *marker = endMarker - (len % 16);
58#if 0
59 if((int)buff & 0x3)
60 printk("unaligned buff %p\n", buff);
61 __delay(900); /* extra delay of 90 us to test performance hit */
62#endif
63 BITON;
64 while (buff < marker) {
65 sum += *((unsigned short *)buff)++;
66 sum += *((unsigned short *)buff)++;
67 sum += *((unsigned short *)buff)++;
68 sum += *((unsigned short *)buff)++;
69 sum += *((unsigned short *)buff)++;
70 sum += *((unsigned short *)buff)++;
71 sum += *((unsigned short *)buff)++;
72 sum += *((unsigned short *)buff)++;
73 }
74 marker = endMarker - (len % 2);
75 while(buff < marker) {
76 sum += *((unsigned short *)buff)++;
77 }
78 if(endMarker - buff > 0) {
79 sum += *buff; /* add extra byte seperately */
80 }
81 BITOFF;
82 return(sum);
83}
84
85EXPORT_SYMBOL(csum_partial);