FFmpeg
cpu.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "config.h"
20 
21 #ifdef __APPLE__
22 #include <sys/sysctl.h>
23 #elif defined(__linux__)
24 #include <asm/cputable.h>
25 #include <linux/auxvec.h>
26 #include <fcntl.h>
27 #if HAVE_UNISTD_H
28 #include <unistd.h>
29 #endif
30 #elif defined(__NetBSD__) || defined(__OpenBSD__)
31 #include <sys/types.h>
32 #include <sys/sysctl.h>
33 #include <machine/cpu.h>
34 #elif defined(__AMIGAOS4__)
35 #include <exec/exec.h>
36 #include <interfaces/exec.h>
37 #include <proto/exec.h>
38 #endif /* __APPLE__ */
39 
40 #include "libavutil/avassert.h"
41 #include "libavutil/cpu.h"
42 #include "libavutil/cpu_internal.h"
43 
44 /**
45  * This function MAY rely on signal() or fork() in order to make sure AltiVec
46  * is present.
47  */
49 {
50 #if HAVE_ALTIVEC
51 #ifdef __AMIGAOS4__
52  ULONG result = 0;
53  extern struct ExecIFace *IExec;
54 
55  IExec->GetCPUInfoTags(GCIT_VectorUnit, &result, TAG_DONE);
56  if (result == VECTORTYPE_ALTIVEC)
57  return AV_CPU_FLAG_ALTIVEC;
58  return 0;
59 #elif defined(__APPLE__) || defined(__NetBSD__) || defined(__OpenBSD__)
60 #if defined(__NetBSD__) || defined(__OpenBSD__)
61  int sels[2] = {CTL_MACHDEP, CPU_ALTIVEC};
62 #else
63  int sels[2] = {CTL_HW, HW_VECTORUNIT};
64 #endif
65  int has_vu = 0;
66  size_t len = sizeof(has_vu);
67  int err;
68 
69  err = sysctl(sels, 2, &has_vu, &len, NULL, 0);
70 
71  if (err == 0)
72  return has_vu ? AV_CPU_FLAG_ALTIVEC : 0;
73  return 0;
74 #elif defined(__linux__)
75  // The linux kernel could have the altivec support disabled
76  // even if the cpu has it.
77  int i, ret = 0;
78  int fd = open("/proc/self/auxv", O_RDONLY);
79  unsigned long buf[64] = { 0 };
80  ssize_t count;
81 
82  if (fd < 0)
83  return 0;
84 
85  while ((count = read(fd, buf, sizeof(buf))) > 0) {
86  for (i = 0; i < count / sizeof(*buf); i += 2) {
87  if (buf[i] == AT_NULL)
88  goto out;
89  if (buf[i] == AT_HWCAP) {
90  if (buf[i + 1] & PPC_FEATURE_HAS_ALTIVEC)
92 #ifdef PPC_FEATURE_HAS_VSX
93  if (buf[i + 1] & PPC_FEATURE_HAS_VSX)
95 #endif
96  if (ret & AV_CPU_FLAG_VSX)
98  }
99 #ifdef AT_HWCAP2 /* not introduced until glibc 2.18 */
100  else if (buf[i] == AT_HWCAP2) {
101 #ifdef PPC_FEATURE2_ARCH_2_07
102  if (buf[i + 1] & PPC_FEATURE2_ARCH_2_07)
104 #endif
105  }
106 #endif /* AT_HWCAP2 */
107  }
108  }
109 
110 out:
111  close(fd);
112  return ret;
113 #elif CONFIG_RUNTIME_CPUDETECT && defined(__linux__)
114 #define PVR_G4_7400 0x000C
115 #define PVR_G5_970 0x0039
116 #define PVR_G5_970FX 0x003C
117 #define PVR_G5_970MP 0x0044
118 #define PVR_G5_970GX 0x0045
119 #define PVR_POWER6 0x003E
120 #define PVR_POWER7 0x003F
121 #define PVR_POWER8 0x004B
122 #define PVR_CELL_PPU 0x0070
123  int ret = 0;
124  int proc_ver;
125  // Support of mfspr PVR emulation added in Linux 2.6.17.
126  __asm__ volatile("mfspr %0, 287" : "=r" (proc_ver));
127  proc_ver >>= 16;
128  if (proc_ver & 0x8000 ||
129  proc_ver == PVR_G4_7400 ||
130  proc_ver == PVR_G5_970 ||
131  proc_ver == PVR_G5_970FX ||
132  proc_ver == PVR_G5_970MP ||
133  proc_ver == PVR_G5_970GX ||
134  proc_ver == PVR_POWER6 ||
135  proc_ver == PVR_POWER7 ||
136  proc_ver == PVR_POWER8 ||
137  proc_ver == PVR_CELL_PPU)
139  if (proc_ver == PVR_POWER7 ||
140  proc_ver == PVR_POWER8)
141  ret |= AV_CPU_FLAG_VSX;
142  if (proc_ver == PVR_POWER8)
144 
145  return ret;
146 #else
147  // Since we were compiled for AltiVec, just assume we have it
148  // until someone comes up with a proper way (not involving signal hacks).
149  return AV_CPU_FLAG_ALTIVEC;
150 #endif /* __AMIGAOS4__ */
151 #endif /* HAVE_ALTIVEC */
152  return 0;
153 }
154 
156 {
157  int flags = av_get_cpu_flags();
158 
159  if (flags & (AV_CPU_FLAG_ALTIVEC |
162  return 16;
163 
164  return 8;
165 }
out
FILE * out
Definition: movenc.c:55
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:103
AV_CPU_FLAG_VSX
#define AV_CPU_FLAG_VSX
ISA 2.06.
Definition: cpu.h:61
avassert.h
cpu_internal.h
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:40
result
and forward the result(frame or status change) to the corresponding input. If nothing is possible
NULL
#define NULL
Definition: coverity.c:32
AV_CPU_FLAG_ALTIVEC
#define AV_CPU_FLAG_ALTIVEC
standard
Definition: cpu.h:60
cpu.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
ff_get_cpu_flags_ppc
int ff_get_cpu_flags_ppc(void)
This function MAY rely on signal() or fork() in order to make sure AltiVec is present.
Definition: cpu.c:48
len
int len
Definition: vorbis_enc_data.h:426
ret
ret
Definition: filter_design.txt:187
__asm__
__asm__(".macro parse_r var r\n\t" "\\var = -1\n\t" _IFC_REG(0) _IFC_REG(1) _IFC_REG(2) _IFC_REG(3) _IFC_REG(4) _IFC_REG(5) _IFC_REG(6) _IFC_REG(7) _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11) _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15) _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19) _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23) _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27) _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31) ".iflt \\var\n\t" ".error \"Unable to parse register name \\r\"\n\t" ".endif\n\t" ".endm")
AV_CPU_FLAG_POWER8
#define AV_CPU_FLAG_POWER8
ISA 2.07.
Definition: cpu.h:62
ff_get_cpu_max_align_ppc
size_t ff_get_cpu_max_align_ppc(void)
Definition: cpu.c:155
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
read
static uint32_t BS_FUNC() read(BSCTX *bc, unsigned int n)
Return n bits from the buffer, n has to be in the 0-32 range.
Definition: bitstream_template.h:231