1 // SPDX-License-Identifier: GPL-2.0 2 #include <sys/types.h> 3 #include <errno.h> 4 #include <unistd.h> 5 #include <stdio.h> 6 #include <stdlib.h> 7 #include <string.h> 8 #include <regex.h> 9 10 #include "../../../util/debug.h" 11 #include "../../../util/header.h" 12 #include "cpuid.h" 13 14 void get_cpuid_0(char *vendor, unsigned int *lvl) 15 { 16 unsigned int b, c, d; 17 18 cpuid(0, 0, lvl, &b, &c, &d); 19 strncpy(&vendor[0], (char *)(&b), 4); 20 strncpy(&vendor[4], (char *)(&d), 4); 21 strncpy(&vendor[8], (char *)(&c), 4); 22 vendor[12] = '\0'; 23 } 24 25 static int 26 __get_cpuid(char *buffer, size_t sz, const char *fmt) 27 { 28 unsigned int a, b, c, d, lvl; 29 int family = -1, model = -1, step = -1; 30 int nb; 31 char vendor[16]; 32 33 get_cpuid_0(vendor, &lvl); 34 35 if (lvl >= 1) { 36 cpuid(1, 0, &a, &b, &c, &d); 37 38 family = (a >> 8) & 0xf; /* bits 11 - 8 */ 39 model = (a >> 4) & 0xf; /* Bits 7 - 4 */ 40 step = a & 0xf; 41 42 /* extended family */ 43 if (family == 0xf) 44 family += (a >> 20) & 0xff; 45 46 /* extended model */ 47 if (family >= 0x6) 48 model += ((a >> 16) & 0xf) << 4; 49 } 50 nb = scnprintf(buffer, sz, fmt, vendor, family, model, step); 51 52 /* look for end marker to ensure the entire data fit */ 53 if (strchr(buffer, '$')) { 54 buffer[nb-1] = '\0'; 55 return 0; 56 } 57 return ENOBUFS; 58 } 59 60 int 61 get_cpuid(char *buffer, size_t sz) 62 { 63 return __get_cpuid(buffer, sz, "%s,%u,%u,%u$"); 64 } 65 66 char * 67 get_cpuid_str(struct perf_pmu *pmu __maybe_unused) 68 { 69 char *buf = malloc(128); 70 71 if (buf && __get_cpuid(buf, 128, "%s-%u-%X-%X$") < 0) { 72 free(buf); 73 return NULL; 74 } 75 return buf; 76 } 77 78 /* Full CPUID format for x86 is vendor-family-model-stepping */ 79 static bool is_full_cpuid(const char *id) 80 { 81 const char *tmp = id; 82 int count = 0; 83 84 while ((tmp = strchr(tmp, '-')) != NULL) { 85 count++; 86 tmp++; 87 } 88 89 if (count == 3) 90 return true; 91 92 return false; 93 } 94 95 int strcmp_cpuid_str(const char *mapcpuid, const char *id) 96 { 97 regex_t re; 98 regmatch_t pmatch[1]; 99 int match; 100 bool full_mapcpuid = is_full_cpuid(mapcpuid); 101 bool full_cpuid = is_full_cpuid(id); 102 103 /* 104 * Full CPUID format is required to identify a platform. 105 * Error out if the cpuid string is incomplete. 106 */ 107 if (full_mapcpuid && !full_cpuid) { 108 pr_info("Invalid CPUID %s. Full CPUID is required, " 109 "vendor-family-model-stepping\n", id); 110 return 1; 111 } 112 113 if (regcomp(&re, mapcpuid, REG_EXTENDED) != 0) { 114 /* Warn unable to generate match particular string. */ 115 pr_info("Invalid regular expression %s\n", mapcpuid); 116 return 1; 117 } 118 119 match = !regexec(&re, id, 1, pmatch, 0); 120 regfree(&re); 121 if (match) { 122 size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so); 123 size_t cpuid_len; 124 125 /* If the full CPUID format isn't required, 126 * ignoring the stepping. 127 */ 128 if (!full_mapcpuid && full_cpuid) 129 cpuid_len = strrchr(id, '-') - id; 130 else 131 cpuid_len = strlen(id); 132 133 /* Verify the entire string matched. */ 134 if (match_len == cpuid_len) 135 return 0; 136 } 137 138 return 1; 139 } 140