util/cpuinfo-ppc.c

   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 #include <asm/cputable.h>
  10 #ifdef CONFIG_GETAUXVAL
  11 # include <sys/auxv.h>
  12 #else
  13 # include "elf.h"
  14 #endif
  15
  16 unsigned cpuinfo;
  17
  18 /* Called both as constructor and (possibly) via other constructors. */
  19 unsigned __attribute__((constructor)) cpuinfo_init(void)
  20 {
  21     unsigned info = cpuinfo;
  22     unsigned long hwcap, hwcap2;
  23
  24     if (info) {
  25         return info;
  26     }
  27
  28     hwcap = qemu_getauxval(AT_HWCAP);
  29     hwcap2 = qemu_getauxval(AT_HWCAP2);
  30     info = CPUINFO_ALWAYS;
  31
  32     /* Version numbers are monotonic, and so imply all lower versions. */
  33     if (hwcap2 & PPC_FEATURE2_ARCH_3_1) {
  34         info |= CPUINFO_V3_1 | CPUINFO_V3_0 | CPUINFO_V2_07 | CPUINFO_V2_06;
  35     } else if (hwcap2 & PPC_FEATURE2_ARCH_3_00) {
  36         info |= CPUINFO_V3_0 | CPUINFO_V2_07 | CPUINFO_V2_06;
  37     } else if (hwcap2 & PPC_FEATURE2_ARCH_2_07) {
  38         info |= CPUINFO_V2_07 | CPUINFO_V2_06;
  39     } else if (hwcap & PPC_FEATURE_ARCH_2_06) {
  40         info |= CPUINFO_V2_06;
  41     }
  42
  43     if (hwcap2 & PPC_FEATURE2_ISEL) {
  44         info |= CPUINFO_ISEL;
  45     }
  46     if (hwcap & PPC_FEATURE_HAS_ALTIVEC) {
  47         info |= CPUINFO_ALTIVEC;
  48         /* We only care about the portion of VSX that overlaps Altivec. */
  49         if (hwcap & PPC_FEATURE_HAS_VSX) {
  50             info |= CPUINFO_VSX;
  51             /*
  52              * We use VSX especially for little-endian, but we should
  53              * always have both anyway, since VSX came with Power7
  54              * and crypto came with Power8.
  55              */
  56             if (hwcap2 & PPC_FEATURE2_VEC_CRYPTO) {
  57                 info |= CPUINFO_CRYPTO;
  58             }
  59         }
  60     }
  61
  62     cpuinfo = info;
  63     return info;
  64 }