1 /*
2 * SPDX-License-Identifier: BSD-3-Clause
3 * Copyright (C) IBM Corporation 2014.
4 */
5
6 #include "rte_cpuflags.h"
7
8 #include <elf.h>
9 #include <fcntl.h>
10 #include <assert.h>
11 #include <string.h>
12 #include <unistd.h>
13
14 /* Symbolic values for the entries in the auxiliary table */
15 #define AT_HWCAP 16
16 #define AT_HWCAP2 26
17
18 /* software based registers */
19 enum cpu_register_t {
20 REG_NONE = 0,
21 REG_HWCAP,
22 REG_HWCAP2,
23 REG_MAX
24 };
25
26 typedef uint32_t hwcap_registers_t[REG_MAX];
27
28 struct feature_entry {
29 uint32_t reg;
30 uint32_t bit;
31 #define CPU_FLAG_NAME_MAX_LEN 64
32 char name[CPU_FLAG_NAME_MAX_LEN];
33 };
34
35 #define FEAT_DEF(name, reg, bit) \
36 [RTE_CPUFLAG_##name] = {reg, bit, #name},
37
38 const struct feature_entry rte_cpu_feature_table[] = {
39 FEAT_DEF(PPC_LE, REG_HWCAP, 0)
40 FEAT_DEF(TRUE_LE, REG_HWCAP, 1)
41 FEAT_DEF(PSERIES_PERFMON_COMPAT, REG_HWCAP, 6)
42 FEAT_DEF(VSX, REG_HWCAP, 7)
43 FEAT_DEF(ARCH_2_06, REG_HWCAP, 8)
44 FEAT_DEF(POWER6_EXT, REG_HWCAP, 9)
45 FEAT_DEF(DFP, REG_HWCAP, 10)
46 FEAT_DEF(PA6T, REG_HWCAP, 11)
47 FEAT_DEF(ARCH_2_05, REG_HWCAP, 12)
48 FEAT_DEF(ICACHE_SNOOP, REG_HWCAP, 13)
49 FEAT_DEF(SMT, REG_HWCAP, 14)
50 FEAT_DEF(BOOKE, REG_HWCAP, 15)
51 FEAT_DEF(CELLBE, REG_HWCAP, 16)
52 FEAT_DEF(POWER5_PLUS, REG_HWCAP, 17)
53 FEAT_DEF(POWER5, REG_HWCAP, 18)
54 FEAT_DEF(POWER4, REG_HWCAP, 19)
55 FEAT_DEF(NOTB, REG_HWCAP, 20)
56 FEAT_DEF(EFP_DOUBLE, REG_HWCAP, 21)
57 FEAT_DEF(EFP_SINGLE, REG_HWCAP, 22)
58 FEAT_DEF(SPE, REG_HWCAP, 23)
59 FEAT_DEF(UNIFIED_CACHE, REG_HWCAP, 24)
60 FEAT_DEF(4xxMAC, REG_HWCAP, 25)
61 FEAT_DEF(MMU, REG_HWCAP, 26)
62 FEAT_DEF(FPU, REG_HWCAP, 27)
63 FEAT_DEF(ALTIVEC, REG_HWCAP, 28)
64 FEAT_DEF(PPC601, REG_HWCAP, 29)
65 FEAT_DEF(PPC64, REG_HWCAP, 30)
66 FEAT_DEF(PPC32, REG_HWCAP, 31)
67 FEAT_DEF(TAR, REG_HWCAP2, 26)
68 FEAT_DEF(LSEL, REG_HWCAP2, 27)
69 FEAT_DEF(EBB, REG_HWCAP2, 28)
70 FEAT_DEF(DSCR, REG_HWCAP2, 29)
71 FEAT_DEF(HTM, REG_HWCAP2, 30)
72 FEAT_DEF(ARCH_2_07, REG_HWCAP2, 31)
73 };
74
75 /*
76 * Read AUXV software register and get cpu features for Power
77 */
78 static void
rte_cpu_get_features(hwcap_registers_t out)79 rte_cpu_get_features(hwcap_registers_t out)
80 {
81 out[REG_HWCAP] = rte_cpu_getauxval(AT_HWCAP);
82 out[REG_HWCAP2] = rte_cpu_getauxval(AT_HWCAP2);
83 }
84
85 /*
86 * Checks if a particular flag is available on current machine.
87 */
88 int
rte_cpu_get_flag_enabled(enum rte_cpu_flag_t feature)89 rte_cpu_get_flag_enabled(enum rte_cpu_flag_t feature)
90 {
91 const struct feature_entry *feat;
92 hwcap_registers_t regs = {0};
93
94 if ((unsigned int)feature >= RTE_DIM(rte_cpu_feature_table))
95 return -ENOENT;
96
97 feat = &rte_cpu_feature_table[feature];
98 if (feat->reg == REG_NONE)
99 return -EFAULT;
100
101 rte_cpu_get_features(regs);
102 return (regs[feat->reg] >> feat->bit) & 1;
103 }
104
105 const char *
rte_cpu_get_flag_name(enum rte_cpu_flag_t feature)106 rte_cpu_get_flag_name(enum rte_cpu_flag_t feature)
107 {
108 if ((unsigned int)feature >= RTE_DIM(rte_cpu_feature_table))
109 return NULL;
110 return rte_cpu_feature_table[feature].name;
111 }
112
113 void
rte_cpu_get_intrinsics_support(struct rte_cpu_intrinsics * intrinsics)114 rte_cpu_get_intrinsics_support(struct rte_cpu_intrinsics *intrinsics)
115 {
116 memset(intrinsics, 0, sizeof(*intrinsics));
117 }
118