-
Notifications
You must be signed in to change notification settings - Fork 2
/
cacheUtil.c
81 lines (75 loc) · 2.75 KB
/
cacheUtil.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
/* $Id$ */
/* determine the machine's cache line size */
/*
* Authorship
* ----------
* This software (libbspExt - extensions to ppc and some other BSPs)
* was created by
*
* Till Straumann <[email protected]>, 2002-2008,
* Stanford Linear Accelerator Center, Stanford University.
*
* Acknowledgement of sponsorship
* ------------------------------
* This software was produced by
* the Stanford Linear Accelerator Center, Stanford University,
* under Contract DE-AC03-76SFO0515 with the Department of Energy.
*
* Government disclaimer of liability
* ----------------------------------
* Neither the United States nor the United States Department of Energy,
* nor any of their employees, makes any warranty, express or implied, or
* assumes any legal liability or responsibility for the accuracy,
* completeness, or usefulness of any data, apparatus, product, or process
* disclosed, or represents that its use would not infringe privately owned
* rights.
*
* Stanford disclaimer of liability
* --------------------------------
* Stanford University makes no representations or warranties, express or
* implied, nor assumes any liability for the use of this software.
*
* Stanford disclaimer of copyright
* --------------------------------
* Stanford University, owner of the copyright, hereby disclaims its
* copyright and all other rights in this software. Hence, anyone may
* freely use it for any purpose without restriction.
*
* Maintenance of notices
* ----------------------
* In the interest of clarity regarding the origin and status of this
* SLAC software, this and all the preceding Stanford University notices
* are to remain affixed to any copy or derivative of this software made
* or distributed by the recipient and are to be affixed to any copy of
* software made or distributed by the recipient that contains a copy or
* derivative of this software.
*
* ------------------ SLAC Software Notices, Set 4 OTT.002a, 2004 FEB 03
*/
#include "bspExt.h"
#include <malloc.h>
#include <assert.h>
long bspExtCacheLineSize=0;
/* determine the machine's cache line size
* NOTE: this works only on an enabled cache
* it raises an exception otherwise...
*/
#define MAX_DETECT 128
long __bspExtGetCacheLineSize(void)
{
unsigned char *tmp, *p, *q;
/* get a buffer */
tmp=malloc(3*MAX_DETECT);
/* fill with nonzero values */
memset(tmp, 0xff, 3*MAX_DETECT);
/* align to MAX_DETECT */
p = (unsigned char*)(((unsigned long)tmp + MAX_DETECT - 1) & ~(MAX_DETECT - 1));
/* clear one cache line */
__asm__ __volatile__("dcbz 0, %0"::"r"(p));
/* search for the last 0 */
for (q=p; q<tmp+3*MAX_DETECT && !*q; q++);
free(tmp);
/* make sure it's less than MAX_DETECT */
assert(q-p <= MAX_DETECT);
return q-p;
}