pixman-ppc.c revision 1176bdada62cabc6ec4b0308a930e83b679d5d36 
1/*
2 * Copyright © 2000 SuSE, Inc.
3 * Copyright © 2007 Red Hat, Inc.
4 *
5 * Permission to use, copy, modify, distribute, and sell this software and its
6 * documentation for any purpose is hereby granted without fee, provided that
7 * the above copyright notice appear in all copies and that both that
8 * copyright notice and this permission notice appear in supporting
9 * documentation, and that the name of SuSE not be used in advertising or
10 * publicity pertaining to distribution of the software without specific,
11 * written prior permission.  SuSE makes no representations about the
12 * suitability of this software for any purpose.  It is provided "as is"
13 * without express or implied warranty.
14 *
15 * SuSE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL SuSE
17 * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
19 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
20 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 */
22#ifdef HAVE_CONFIG_H
23#include <config.h>
24#endif
25
26#include "pixman-private.h"
27
28#ifdef USE_VMX
29
30/* The CPU detection code needs to be in a file not compiled with
31 * "-maltivec -mabi=altivec", as gcc would try to save vector register
32 * across function calls causing SIGILL on cpus without Altivec/vmx.
33 */
34#ifdef __APPLE__
35#include <sys/sysctl.h>
36
37static pixman_bool_t
38pixman_have_vmx (void)
39{
40    int error, have_vmx;
41    size_t length = sizeof(have_vmx);
42
43    error = sysctlbyname ("hw.optional.altivec", &have_vmx, &length, NULL, 0);
44
45    if (error)
46	return FALSE;
47
48    return have_vmx;
49}
50
51#elif defined (__OpenBSD__)
52#include <sys/param.h>
53#include <sys/sysctl.h>
54#include <machine/cpu.h>
55
56static pixman_bool_t
57pixman_have_vmx (void)
58{
59    int error, have_vmx;
60    int mib[2] = { CTL_MACHDEP, CPU_ALTIVEC };
61    size_t length = sizeof(have_vmx);
62
63    error = sysctl (mib, 2, &have_vmx, &length, NULL, 0);
64
65    if (error != 0)
66	return FALSE;
67
68    return have_vmx;
69}
70
71#elif defined (__linux__)
72
73#include <sys/types.h>
74#include <sys/stat.h>
75#include <fcntl.h>
76#include <unistd.h>
77#include <stdio.h>
78#include <linux/auxvec.h>
79#include <asm/cputable.h>
80
81static pixman_bool_t
82pixman_have_vmx (void)
83{
84    int have_vmx = FALSE;
85    int fd;
86    struct
87    {
88	unsigned long type;
89	unsigned long value;
90    } aux;
91
92    fd = open ("/proc/self/auxv", O_RDONLY);
93    if (fd >= 0)
94    {
95	while (read (fd, &aux, sizeof (aux)) == sizeof (aux))
96	{
97	    if (aux.type == AT_HWCAP && (aux.value & PPC_FEATURE_HAS_ALTIVEC))
98	    {
99		have_vmx = TRUE;
100		break;
101	    }
102	}
103
104	close (fd);
105    }
106
107    return have_vmx;
108}
109
110#else /* !__APPLE__ && !__OpenBSD__ && !__linux__ */
111#include <signal.h>
112#include <setjmp.h>
113
114static jmp_buf jump_env;
115
116static void
117vmx_test (int        sig,
118	  siginfo_t *si,
119	  void *     unused)
120{
121    longjmp (jump_env, 1);
122}
123
124static pixman_bool_t
125pixman_have_vmx (void)
126{
127    struct sigaction sa, osa;
128    int jmp_result;
129
130    sa.sa_flags = SA_SIGINFO;
131    sigemptyset (&sa.sa_mask);
132    sa.sa_sigaction = vmx_test;
133    sigaction (SIGILL, &sa, &osa);
134    jmp_result = setjmp (jump_env);
135    if (jmp_result == 0)
136    {
137	asm volatile ( "vor 0, 0, 0" );
138    }
139    sigaction (SIGILL, &osa, NULL);
140    return (jmp_result == 0);
141}
142
143#endif /* __APPLE__ */
144#endif /* USE_VMX */
145
146pixman_implementation_t *
147_pixman_ppc_get_implementations (pixman_implementation_t *imp)
148{
149#ifdef USE_VMX
150    if (!_pixman_disabled ("vmx") && pixman_have_vmx ())
151	imp = _pixman_implementation_create_vmx (imp);
152#endif
153
154    return imp;
155}
156