util/cpuinfo-aarch64.c

   1 /*
   2  * SPDX-License-Identifier: GPL-2.0-or-later
   3  * Host specific cpu identification for AArch64.
   4  */
   5
   6 #include "qemu/osdep.h"
   7 #include "host/cpuinfo.h"
   8
   9 #ifdef CONFIG_LINUX
  10 # ifdef CONFIG_GETAUXVAL
  11 #  include <sys/auxv.h>
  12 # else
  13 #  include <asm/hwcap.h>
  14 #  include "elf.h"
  15 # endif
  16 # ifndef HWCAP2_BTI
  17 #  define HWCAP2_BTI 0  /* added in glibc 2.32 */
  18 # endif
  19 #endif
  20 #ifdef CONFIG_DARWIN
  21 # include <sys/sysctl.h>
  22 #endif
  23 #ifdef __OpenBSD__
  24 # include <machine/armreg.h>
  25 # include <machine/cpu.h>
  26 # include <sys/types.h>
  27 # include <sys/sysctl.h>
  28 #endif
  29
  30 unsigned cpuinfo;
  31
  32 #ifdef CONFIG_DARWIN
  33 static bool sysctl_for_bool(const char *name)
  34 {
  35     int val = 0;
  36     size_t len = sizeof(val);
  37
  38     if (sysctlbyname(name, &val, &len, NULL, 0) == 0) {
  39         return val != 0;
  40     }
  41
  42     /*
  43      * We might in the future ask for properties not present in older kernels,
  44      * but we're only asking about static properties, all of which should be
  45      * 'int'.  So we shouldn't see ENOMEM (val too small), or any of the other
  46      * more exotic errors.
  47      */
  48     assert(errno == ENOENT);
  49     return false;
  50 }
  51 #endif
  52
  53 /* Called both as constructor and (possibly) via other constructors. */
  54 unsigned __attribute__((constructor)) cpuinfo_init(void)
  55 {
  56     unsigned info = cpuinfo;
  57
  58     if (info) {
  59         return info;
  60     }
  61
  62     info = CPUINFO_ALWAYS;
  63
  64 #ifdef CONFIG_LINUX
  65     unsigned long hwcap = qemu_getauxval(AT_HWCAP);
  66     info |= (hwcap & HWCAP_ATOMICS ? CPUINFO_LSE : 0);
  67     info |= (hwcap & HWCAP_USCAT ? CPUINFO_LSE2 : 0);
  68     info |= (hwcap & HWCAP_AES ? CPUINFO_AES : 0);
  69     info |= (hwcap & HWCAP_PMULL ? CPUINFO_PMULL : 0);
  70
  71     unsigned long hwcap2 = qemu_getauxval(AT_HWCAP2);
  72     info |= (hwcap2 & HWCAP2_BTI ? CPUINFO_BTI : 0);
  73 #endif
  74 #ifdef CONFIG_DARWIN
  75     info |= sysctl_for_bool("hw.optional.arm.FEAT_LSE") * CPUINFO_LSE;
  76     info |= sysctl_for_bool("hw.optional.arm.FEAT_LSE2") * CPUINFO_LSE2;
  77     info |= sysctl_for_bool("hw.optional.arm.FEAT_AES") * CPUINFO_AES;
  78     info |= sysctl_for_bool("hw.optional.arm.FEAT_PMULL") * CPUINFO_PMULL;
  79     info |= sysctl_for_bool("hw.optional.arm.FEAT_BTI") * CPUINFO_BTI;
  80 #endif
  81 #ifdef __OpenBSD__
  82     int mib[2];
  83     uint64_t isar0;
  84     uint64_t pfr1;
  85     size_t len;
  86
  87     mib[0] = CTL_MACHDEP;
  88     mib[1] = CPU_ID_AA64ISAR0;
  89     len = sizeof(isar0);
  90     if (sysctl(mib, 2, &isar0, &len, NULL, 0) != -1) {
  91         if (ID_AA64ISAR0_ATOMIC(isar0) >= ID_AA64ISAR0_ATOMIC_IMPL) {
  92             info |= CPUINFO_LSE;
  93         }
  94         if (ID_AA64ISAR0_AES(isar0) >= ID_AA64ISAR0_AES_BASE) {
  95             info |= CPUINFO_AES;
  96         }
  97         if (ID_AA64ISAR0_AES(isar0) >= ID_AA64ISAR0_AES_PMULL) {
  98             info |= CPUINFO_PMULL;
  99         }
 100     }
 101
 102     mib[0] = CTL_MACHDEP;
 103     mib[1] = CPU_ID_AA64PFR1;
 104     len = sizeof(pfr1);
 105     if (sysctl(mib, 2, &pfr1, &len, NULL, 0) != -1) {
 106         if (ID_AA64PFR1_BT(pfr1) >= ID_AA64PFR1_BT_IMPL) {
 107             info |= CPUINFO_BTI;
 108         }
 109     }
 110 #endif
 111
 112     cpuinfo = info;
 113     return info;
 114 }