1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29#pragma weak _getisax = getisax
30
31#include "lint.h"
32#include <sys/types.h>
33#include <sys/auxv.h>
34
35extern long ___getauxval(int type);
36
37/*
38 * Return the 'hwcap' vector of bits in the AT_SUN_HWCAP aux vector entry.
39 *
40 * At this time, the worst-case implementation only uses 13 bits, but for
41 * future-proofing, we allow the interface to describe an arbitrary length
42 * array of 32-bit words.
43 *
44 * As a convenience, the routine returns the maximum number of array alements
45 * that may contain non-zero values.
46 */
47uint_t
48getisax(uint32_t *array, uint_t n)
49{
50	int i;
51	static uint32_t auxv_hwcap;
52
53	if (auxv_hwcap == 0)
54		auxv_hwcap = (uint32_t)___getauxval(AT_SUN_HWCAP);
55
56	if (n > 0) {
57		if (n >= 1)
58			array[0] = auxv_hwcap;
59		for (i = 1; i < n; i++)
60			array[i] = 0;
61	}
62	return (auxv_hwcap == 0 ? 0 : 1);
63}
64