tests/arm64_features.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #if !defined(__APPLE__) && defined(VGA_arm64)
   5 #include <sys/auxv.h>
   6 #endif
   7
   8 // This file determines arm64 features a processor supports.
   9 // Arm processors do not have a x86-like cpuinfo instruction. Instead the
  10 // getauxval() syscall is used with capabilities parameters: getauxval(AT_HWCAP)
  11 // and getauxval(AT_HWCAP2).
  12 //
  13 // We return:
  14 // - 0 if the machine has the asked-for feature.
  15 // - 1 if the machine doesn't have the asked-for feature.
  16 // - 2 if the asked-for feature isn't recognised (this will always be the case
  17 //     for any feature if run on a non-arm64 machine).
  18 // - 3 if there was a usage error (it also prints an error message).
  19 #define FEATURE_PRESENT       0
  20 #define FEATURE_NOT_PRESENT   1
  21 #define UNRECOGNISED_FEATURE  2
  22 #define USAGE_ERROR           3
  23
  24 #define False  0
  25 #define True   1
  26 typedef int    Bool;
  27
  28 #if defined(VGA_arm64)
  29
  30 // The processor's capabilities/features are returned by getauxval() as an
  31 // unsigned long with each bit representing a capability/feature.
  32 #define HWCAP_FP            (1 << 0)
  33 #define HWCAP_ASIMD         (1 << 1)
  34 #define HWCAP_EVTSTRM       (1 << 2)
  35 #define HWCAP_AES           (1 << 3)
  36 #define HWCAP_PMULL         (1 << 4)
  37 #define HWCAP_SHA1          (1 << 5)
  38 #define HWCAP_SHA2          (1 << 6)
  39 #define HWCAP_CRC32         (1 << 7)
  40 #define HWCAP_ATOMICS       (1 << 8)
  41 #define HWCAP_FPHP          (1 << 9)
  42 #define HWCAP_ASIMDHP       (1 << 10)
  43 #define HWCAP_CPUID         (1 << 11)
  44 #define HWCAP_ASIMDRDM      (1 << 12)
  45 #define HWCAP_JSCVT         (1 << 13)
  46 #define HWCAP_FCMA          (1 << 14)
  47 #define HWCAP_LRCPC         (1 << 15)
  48 #define HWCAP_DCPOP         (1 << 16)
  49 #define HWCAP_SHA3          (1 << 17)
  50 #define HWCAP_SM3           (1 << 18)
  51 #define HWCAP_SM4           (1 << 19)
  52 #define HWCAP_ASIMDDP       (1 << 20)
  53 #define HWCAP_SHA512        (1 << 21)
  54 #define HWCAP_SVE           (1 << 22)
  55 #define HWCAP_ASIMDFHM      (1 << 23)
  56 #define HWCAP_DIT           (1 << 24)
  57 #define HWCAP_USCAT         (1 << 25)
  58 #define HWCAP_ILRCPC        (1 << 26)
  59 #define HWCAP_FLAGM         (1 << 27)
  60 #define HWCAP_SSBS          (1 << 28)
  61 #define HWCAP_SB            (1 << 29)
  62 #define HWCAP_PACA          (1 << 30)
  63 #define HWCAP_PACG          (1UL << 31)
  64
  65 #define HWCAP2_DCPODP       (1 << 0)
  66 #define HWCAP2_SVE2         (1 << 1)
  67 #define HWCAP2_SVEAES       (1 << 2)
  68 #define HWCAP2_SVEPMULL     (1 << 3)
  69 #define HWCAP2_SVEBITPERM   (1 << 4)
  70 #define HWCAP2_SVESHA3      (1 << 5)
  71 #define HWCAP2_SVESM4       (1 << 6)
  72 #define HWCAP2_FLAGM2       (1 << 7)
  73 #define HWCAP2_FRINT        (1 << 8)
  74
  75 unsigned long hwcaps[] = {
  76    HWCAP_FP,     HWCAP_ASIMD,  HWCAP_EVTSTRM, HWCAP_AES,     HWCAP_PMULL,
  77    HWCAP_SHA1,   HWCAP_SHA2,   HWCAP_CRC32,   HWCAP_ATOMICS, HWCAP_FPHP,
  78    HWCAP_ASIMDHP,HWCAP_CPUID,  HWCAP_ASIMDRDM,HWCAP_JSCVT,   HWCAP_FCMA,
  79    HWCAP_LRCPC,  HWCAP_DCPOP,  HWCAP_SHA3,    HWCAP_SM3,     HWCAP_SM4,
  80    HWCAP_ASIMDDP,HWCAP_SHA512, HWCAP_SVE,     HWCAP_ASIMDFHM,HWCAP_DIT,
  81    HWCAP_USCAT,  HWCAP_ILRCPC, HWCAP_FLAGM,   HWCAP_SSBS,    HWCAP_SB,
  82    HWCAP_PACA,   HWCAP_PACG,   0ul};
  83
  84 unsigned long hwcaps2[] = {
  85    HWCAP2_DCPODP,     HWCAP2_SVE2,    HWCAP2_SVEAES, HWCAP2_SVEPMULL,
  86    HWCAP2_SVEBITPERM, HWCAP2_SVESHA3, HWCAP2_SVESM4, HWCAP2_FLAGM2,
  87    HWCAP2_FRINT,      0ul};
  88
  89 typedef struct
  90 {
  91    char name[16];
  92    unsigned long cap_bit;
  93 } capability;
  94
  95 capability capabilities[] = {
  96    {"fp",       HWCAP_FP},       {"asimd",    HWCAP_ASIMD},
  97    {"evtstrm",  HWCAP_EVTSTRM},  {"aes",      HWCAP_AES},
  98    {"pmull",    HWCAP_PMULL},    {"sha1",     HWCAP_SHA1},
  99    {"sha2",     HWCAP_SHA2},     {"crc32",    HWCAP_CRC32},
 100    {"atomics",  HWCAP_ATOMICS},  {"fphp",     HWCAP_FPHP},
 101    {"asimdhp",  HWCAP_ASIMDHP},  {"cpuid",    HWCAP_CPUID},
 102    {"asimdrdm", HWCAP_ASIMDRDM}, {"jscvt",    HWCAP_JSCVT},
 103    {"fcma",     HWCAP_FCMA},     {"lrcpc",    HWCAP_LRCPC},
 104    {"dcpop",    HWCAP_DCPOP},    {"sha3",     HWCAP_SHA3},
 105    {"sm3",      HWCAP_SM3},      {"sm4",      HWCAP_SM4},
 106    {"asimddp",  HWCAP_ASIMDDP},  {"sha512",   HWCAP_SHA512},
 107    {"sve",      HWCAP_SVE},      {"asimdfhm", HWCAP_ASIMDFHM},
 108    {"dit",      HWCAP_DIT},      {"uscat",    HWCAP_USCAT},
 109    {"ilrcpc",   HWCAP_ILRCPC},   {"flagm",    HWCAP_FLAGM},
 110    {"ssbs",     HWCAP_SSBS},     {"sb",       HWCAP_SB},
 111    {"paca",     HWCAP_PACA},     {"pacg",     HWCAP_PACG},
 112    {"",         0ul}
 113 };
 114
 115 capability capabilities2[] = {
 116    {"dcpodp",     HWCAP2_DCPODP},     {"sve2",       HWCAP2_SVE2},
 117    {"sveaes",     HWCAP2_SVEAES},     {"svepmull",   HWCAP2_SVEPMULL},
 118    {"svebitperm", HWCAP2_SVEBITPERM}, {"svesha3",    HWCAP2_SVESHA3},
 119    {"svesm4",     HWCAP2_SVESM4},     {"flagm2",     HWCAP2_FLAGM2},
 120    {"frint",      HWCAP2_FRINT},      {"",           0ul}
 121 };
 122
 123 typedef struct
 124 {
 125    unsigned long hwcap;
 126    unsigned long hwcap2;
 127 } hwc;
 128
 129 #define CAPABILITIES_SEARCH_LOOP(hwcversion) \
 130    for (int i = 0; capabilities ## hwcversion[i].cap_bit; ++i) \
 131       if (strcmp(name, capabilities ## hwcversion[i].name) == 0) { \
 132          caps->hwcap ## hwcversion = capabilities ## hwcversion[i].cap_bit; \
 133          return True; \
 134       } \
 135
 136 static Bool get_feature_from_string(const char *name, hwc *caps)
 137 {
 138    caps->hwcap = caps->hwcap2 = 0;
 139    CAPABILITIES_SEARCH_LOOP()
 140    CAPABILITIES_SEARCH_LOOP(2)
 141    return False;
 142 }
 143
 144 static int go(const char* feature_name)
 145 {
 146    hwc hw;
 147    unsigned long hwcap = getauxval(AT_HWCAP);
 148    unsigned long hwcap2 = getauxval(AT_HWCAP2);
 149
 150    if (!get_feature_from_string(feature_name, &hw))
 151       return UNRECOGNISED_FEATURE;
 152
 153    if ((hw.hwcap & hwcap) || (hw.hwcap2 & hwcap2))
 154       return FEATURE_PRESENT;
 155
 156    return FEATURE_NOT_PRESENT;
 157 }
 158
 159 #else
 160
 161 static Bool go(const char* feature_name)
 162 {
 163    // Feature not recognised (non-arm64 machine!)
 164    return UNRECOGNISED_FEATURE;
 165 }
 166
 167 #endif   // defined(VGA_arm64)
 168
 169
 170 //---------------------------------------------------------------------------
 171 // main
 172 //---------------------------------------------------------------------------
 173 int main(int argc, char **argv)
 174 {
 175    if (argc != 2) {
 176       fprintf(stderr, "usage: arm64_features <feature>\n");
 177       exit(USAGE_ERROR);
 178    }
 179    return go(argv[1]);
 180 }