ceph/src/seastar/dpdk/lib/librte_eal/common/arch/arm/rte_cpuflags.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright (C) Cavium, Inc. 2015.
   3  * Copyright(c) 2015 RehiveTech. All rights reserved.
   4  */
   5
   6 #include "rte_cpuflags.h"
   7
   8 #include <elf.h>
   9 #include <fcntl.h>
  10 #include <assert.h>
  11 #include <unistd.h>
  12 #include <string.h>
  13
  14 #ifndef AT_HWCAP
  15 #define AT_HWCAP 16
  16 #endif
  17
  18 #ifndef AT_HWCAP2
  19 #define AT_HWCAP2 26
  20 #endif
  21
  22 #ifndef AT_PLATFORM
  23 #define AT_PLATFORM 15
  24 #endif
  25
  26 enum cpu_register_t {
  27         REG_NONE = 0,
  28         REG_HWCAP,
  29         REG_HWCAP2,
  30         REG_PLATFORM,
  31         REG_MAX
  32 };
  33
  34 typedef uint32_t hwcap_registers_t[REG_MAX];
  35
  36 /**
  37  * Struct to hold a processor feature entry
  38  */
  39 struct feature_entry {
  40         uint32_t reg;
  41         uint32_t bit;
  42 #define CPU_FLAG_NAME_MAX_LEN 64
  43         char name[CPU_FLAG_NAME_MAX_LEN];
  44 };
  45
  46 #define FEAT_DEF(name, reg, bit) \
  47         [RTE_CPUFLAG_##name] = {reg, bit, #name},
  48
  49 #ifdef RTE_ARCH_ARMv7
  50 #define PLATFORM_STR "v7l"
  51 typedef Elf32_auxv_t _Elfx_auxv_t;
  52
  53 const struct feature_entry rte_cpu_feature_table[] = {
  54         FEAT_DEF(SWP,       REG_HWCAP,    0)
  55         FEAT_DEF(HALF,      REG_HWCAP,    1)
  56         FEAT_DEF(THUMB,     REG_HWCAP,    2)
  57         FEAT_DEF(A26BIT,    REG_HWCAP,    3)
  58         FEAT_DEF(FAST_MULT, REG_HWCAP,    4)
  59         FEAT_DEF(FPA,       REG_HWCAP,    5)
  60         FEAT_DEF(VFP,       REG_HWCAP,    6)
  61         FEAT_DEF(EDSP,      REG_HWCAP,    7)
  62         FEAT_DEF(JAVA,      REG_HWCAP,    8)
  63         FEAT_DEF(IWMMXT,    REG_HWCAP,    9)
  64         FEAT_DEF(CRUNCH,    REG_HWCAP,   10)
  65         FEAT_DEF(THUMBEE,   REG_HWCAP,   11)
  66         FEAT_DEF(NEON,      REG_HWCAP,   12)
  67         FEAT_DEF(VFPv3,     REG_HWCAP,   13)
  68         FEAT_DEF(VFPv3D16,  REG_HWCAP,   14)
  69         FEAT_DEF(TLS,       REG_HWCAP,   15)
  70         FEAT_DEF(VFPv4,     REG_HWCAP,   16)
  71         FEAT_DEF(IDIVA,     REG_HWCAP,   17)
  72         FEAT_DEF(IDIVT,     REG_HWCAP,   18)
  73         FEAT_DEF(VFPD32,    REG_HWCAP,   19)
  74         FEAT_DEF(LPAE,      REG_HWCAP,   20)
  75         FEAT_DEF(EVTSTRM,   REG_HWCAP,   21)
  76         FEAT_DEF(AES,       REG_HWCAP2,   0)
  77         FEAT_DEF(PMULL,     REG_HWCAP2,   1)
  78         FEAT_DEF(SHA1,      REG_HWCAP2,   2)
  79         FEAT_DEF(SHA2,      REG_HWCAP2,   3)
  80         FEAT_DEF(CRC32,     REG_HWCAP2,   4)
  81         FEAT_DEF(V7L,       REG_PLATFORM, 0)
  82 };
  83
  84 #elif defined RTE_ARCH_ARM64
  85 #define PLATFORM_STR "aarch64"
  86 typedef Elf64_auxv_t _Elfx_auxv_t;
  87
  88 const struct feature_entry rte_cpu_feature_table[] = {
  89         FEAT_DEF(FP,            REG_HWCAP,    0)
  90         FEAT_DEF(NEON,          REG_HWCAP,    1)
  91         FEAT_DEF(EVTSTRM,       REG_HWCAP,    2)
  92         FEAT_DEF(AES,           REG_HWCAP,    3)
  93         FEAT_DEF(PMULL,         REG_HWCAP,    4)
  94         FEAT_DEF(SHA1,          REG_HWCAP,    5)
  95         FEAT_DEF(SHA2,          REG_HWCAP,    6)
  96         FEAT_DEF(CRC32,         REG_HWCAP,    7)
  97         FEAT_DEF(ATOMICS,       REG_HWCAP,    8)
  98         FEAT_DEF(AARCH64,       REG_PLATFORM, 1)
  99 };
 100 #endif /* RTE_ARCH */
 101
 102 /*
 103  * Read AUXV software register and get cpu features for ARM
 104  */
 105 static void
 106 rte_cpu_get_features(hwcap_registers_t out)
 107 {
 108         out[REG_HWCAP] = rte_cpu_getauxval(AT_HWCAP);
 109         out[REG_HWCAP2] = rte_cpu_getauxval(AT_HWCAP2);
 110         if (!rte_cpu_strcmp_auxval(AT_PLATFORM, PLATFORM_STR))
 111                 out[REG_PLATFORM] = 0x0001;
 112 }
 113
 114 /*
 115  * Checks if a particular flag is available on current machine.
 116  */
 117 int
 118 rte_cpu_get_flag_enabled(enum rte_cpu_flag_t feature)
 119 {
 120         const struct feature_entry *feat;
 121         hwcap_registers_t regs = {0};
 122
 123         if (feature >= RTE_CPUFLAG_NUMFLAGS)
 124                 return -ENOENT;
 125
 126         feat = &rte_cpu_feature_table[feature];
 127         if (feat->reg == REG_NONE)
 128                 return -EFAULT;
 129
 130         rte_cpu_get_features(regs);
 131         return (regs[feat->reg] >> feat->bit) & 1;
 132 }
 133
 134 const char *
 135 rte_cpu_get_flag_name(enum rte_cpu_flag_t feature)
 136 {
 137         if (feature >= RTE_CPUFLAG_NUMFLAGS)
 138                 return NULL;
 139         return rte_cpu_feature_table[feature].name;
 140 }