xref: /openbmc/qemu/util/cpuinfo-ppc.c (revision 13b5ae94)
1 /*
2  * SPDX-License-Identifier: GPL-2.0-or-later
3  * Host specific cpu identification for ppc.
4  */
5 
6 #include "qemu/osdep.h"
7 #include "host/cpuinfo.h"
8 
9 #ifdef CONFIG_LINUX
10 # include <asm/cputable.h>
11 # ifdef CONFIG_GETAUXVAL
12 #  include <sys/auxv.h>
13 # else
14 #  include "elf.h"
15 # endif
16 #endif
17 #ifdef __FreeBSD__
18 # include <machine/cpu.h>
19 # ifndef PPC_FEATURE2_ARCH_3_1
20 #  define PPC_FEATURE2_ARCH_3_1   0
21 # endif
22 # define PPC_FEATURE2_VEC_CRYPTO  PPC_FEATURE2_HAS_VEC_CRYPTO
23 #endif
24 
25 unsigned cpuinfo;
26 
27 /* Called both as constructor and (possibly) via other constructors. */
28 unsigned __attribute__((constructor)) cpuinfo_init(void)
29 {
30     unsigned info = cpuinfo;
31 
32     if (info) {
33         return info;
34     }
35 
36     info = CPUINFO_ALWAYS;
37 
38 #if defined(CONFIG_LINUX) || defined(__FreeBSD__)
39     unsigned long hwcap = qemu_getauxval(AT_HWCAP);
40     unsigned long hwcap2 = qemu_getauxval(AT_HWCAP2);
41 
42     /* Version numbers are monotonic, and so imply all lower versions. */
43     if (hwcap2 & PPC_FEATURE2_ARCH_3_1) {
44         info |= CPUINFO_V3_1 | CPUINFO_V3_0 | CPUINFO_V2_07 | CPUINFO_V2_06;
45     } else if (hwcap2 & PPC_FEATURE2_ARCH_3_00) {
46         info |= CPUINFO_V3_0 | CPUINFO_V2_07 | CPUINFO_V2_06;
47     } else if (hwcap2 & PPC_FEATURE2_ARCH_2_07) {
48         info |= CPUINFO_V2_07 | CPUINFO_V2_06;
49     } else if (hwcap & PPC_FEATURE_ARCH_2_06) {
50         info |= CPUINFO_V2_06;
51     }
52 
53     if (hwcap2 & PPC_FEATURE2_ISEL) {
54         info |= CPUINFO_ISEL;
55     }
56     if (hwcap & PPC_FEATURE_HAS_ALTIVEC) {
57         info |= CPUINFO_ALTIVEC;
58         /* We only care about the portion of VSX that overlaps Altivec. */
59         if (hwcap & PPC_FEATURE_HAS_VSX) {
60             info |= CPUINFO_VSX;
61             /*
62              * We use VSX especially for little-endian, but we should
63              * always have both anyway, since VSX came with Power7
64              * and crypto came with Power8.
65              */
66             if (hwcap2 & PPC_FEATURE2_VEC_CRYPTO) {
67                 info |= CPUINFO_CRYPTO;
68             }
69         }
70     }
71 #endif
72 
73     cpuinfo = info;
74     return info;
75 }
76