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 13 static inline void 14 cpuid(unsigned int op, unsigned int *a, unsigned int *b, unsigned int *c, 15 unsigned int *d) 16 { 17 __asm__ __volatile__ (".byte 0x53\n\tcpuid\n\t" 18 "movl %%ebx, %%esi\n\t.byte 0x5b" 19 : "=a" (*a), 20 "=S" (*b), 21 "=c" (*c), 22 "=d" (*d) 23 : "a" (op)); 24 } 25 26 static int 27 __get_cpuid(char *buffer, size_t sz, const char *fmt) 28 { 29 unsigned int a, b, c, d, lvl; 30 int family = -1, model = -1, step = -1; 31 int nb; 32 char vendor[16]; 33 34 cpuid(0, &lvl, &b, &c, &d); 35 strncpy(&vendor[0], (char *)(&b), 4); 36 strncpy(&vendor[4], (char *)(&d), 4); 37 strncpy(&vendor[8], (char *)(&c), 4); 38 vendor[12] = '\0'; 39 40 if (lvl >= 1) { 41 cpuid(1, &a, &b, &c, &d); 42 43 family = (a >> 8) & 0xf; /* bits 11 - 8 */ 44 model = (a >> 4) & 0xf; /* Bits 7 - 4 */ 45 step = a & 0xf; 46 47 /* extended family */ 48 if (family == 0xf) 49 family += (a >> 20) & 0xff; 50 51 /* extended model */ 52 if (family >= 0x6) 53 model += ((a >> 16) & 0xf) << 4; 54 } 55 nb = scnprintf(buffer, sz, fmt, vendor, family, model, step); 56 57 /* look for end marker to ensure the entire data fit */ 58 if (strchr(buffer, '$')) { 59 buffer[nb-1] = '\0'; 60 return 0; 61 } 62 return ENOBUFS; 63 } 64 65 int 66 get_cpuid(char *buffer, size_t sz) 67 { 68 return __get_cpuid(buffer, sz, "%s,%u,%u,%u$"); 69 } 70 71 char * 72 get_cpuid_str(struct perf_pmu *pmu __maybe_unused) 73 { 74 char *buf = malloc(128); 75 76 if (buf && __get_cpuid(buf, 128, "%s-%u-%X-%X$") < 0) { 77 free(buf); 78 return NULL; 79 } 80 return buf; 81 } 82 83 /* Full CPUID format for x86 is vendor-family-model-stepping */ 84 static bool is_full_cpuid(const char *id) 85 { 86 const char *tmp = id; 87 int count = 0; 88 89 while ((tmp = strchr(tmp, '-')) != NULL) { 90 count++; 91 tmp++; 92 } 93 94 if (count == 3) 95 return true; 96 97 return false; 98 } 99 100 int strcmp_cpuid_str(const char *mapcpuid, const char *id) 101 { 102 regex_t re; 103 regmatch_t pmatch[1]; 104 int match; 105 bool full_mapcpuid = is_full_cpuid(mapcpuid); 106 bool full_cpuid = is_full_cpuid(id); 107 108 /* 109 * Full CPUID format is required to identify a platform. 110 * Error out if the cpuid string is incomplete. 111 */ 112 if (full_mapcpuid && !full_cpuid) { 113 pr_info("Invalid CPUID %s. Full CPUID is required, " 114 "vendor-family-model-stepping\n", id); 115 return 1; 116 } 117 118 if (regcomp(&re, mapcpuid, REG_EXTENDED) != 0) { 119 /* Warn unable to generate match particular string. */ 120 pr_info("Invalid regular expression %s\n", mapcpuid); 121 return 1; 122 } 123 124 match = !regexec(&re, id, 1, pmatch, 0); 125 regfree(&re); 126 if (match) { 127 size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so); 128 size_t cpuid_len; 129 130 /* If the full CPUID format isn't required, 131 * ignoring the stepping. 132 */ 133 if (!full_mapcpuid && full_cpuid) 134 cpuid_len = strrchr(id, '-') - id; 135 else 136 cpuid_len = strlen(id); 137 138 /* Verify the entire string matched. */ 139 if (match_len == cpuid_len) 140 return 0; 141 } 142 143 return 1; 144 } 145