diff options
Diffstat (limited to 'tools/power/cpupower/utils/helpers/cpuid.c')
-rw-r--r-- | tools/power/cpupower/utils/helpers/cpuid.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/tools/power/cpupower/utils/helpers/cpuid.c b/tools/power/cpupower/utils/helpers/cpuid.c new file mode 100644 index 000000000000..71021f3bb69d --- /dev/null +++ b/tools/power/cpupower/utils/helpers/cpuid.c @@ -0,0 +1,145 @@ +#include <stdio.h> +#include <errno.h> +#include <string.h> +#include <unistd.h> +#include <stdlib.h> + +#include "helpers/helpers.h" + +static const char *cpu_vendor_table[X86_VENDOR_MAX] = { + "Unknown", "GenuineIntel", "AuthenticAMD", +}; + +#if defined(__i386__) || defined(__x86_64__) + +/* from gcc */ +#include <cpuid.h> + +/* + * CPUID functions returning a single datum + * + * Define unsigned int cpuid_e[abcd]x(unsigned int op) + */ +#define cpuid_func(reg) \ + unsigned int cpuid_##reg(unsigned int op) \ + { \ + unsigned int eax, ebx, ecx, edx; \ + __cpuid(op, eax, ebx, ecx, edx); \ + return reg; \ + } +cpuid_func(eax); +cpuid_func(ebx); +cpuid_func(ecx); +cpuid_func(edx); + +#endif /* defined(__i386__) || defined(__x86_64__) */ + +/* get_cpu_info + * + * Extract CPU vendor, family, model, stepping info from /proc/cpuinfo + * + * Returns 0 on success or a negativ error code + * + * TBD: Should there be a cpuid alternative for this if /proc is not mounted? + */ +int get_cpu_info(unsigned int cpu, struct cpupower_cpu_info *cpu_info) +{ + FILE *fp; + char value[64]; + unsigned int proc, x; + unsigned int unknown = 0xffffff; + unsigned int cpuid_level, ext_cpuid_level; + + int ret = -EINVAL; + + cpu_info->vendor = X86_VENDOR_UNKNOWN; + cpu_info->family = unknown; + cpu_info->model = unknown; + cpu_info->stepping = unknown; + cpu_info->caps = 0; + + fp = fopen("/proc/cpuinfo", "r"); + if (!fp) + return -EIO; + + while (!feof(fp)) { + if (!fgets(value, 64, fp)) + continue; + value[63 - 1] = '\0'; + + if (!strncmp(value, "processor\t: ", 12)) { + sscanf(value, "processor\t: %u", &proc); + } + if (proc != cpu) + continue; + + /* Get CPU vendor */ + if (!strncmp(value, "vendor_id", 9)) + for (x = 1; x < X86_VENDOR_MAX; x++) { + if (strstr(value, cpu_vendor_table[x])) + cpu_info->vendor = x; + } + /* Get CPU family, etc. */ + else if (!strncmp(value, "cpu family\t: ", 13)) { + sscanf(value, "cpu family\t: %u", + &cpu_info->family); + } + else if (!strncmp(value, "model\t\t: ", 9)) { + sscanf(value, "model\t\t: %u", + &cpu_info->model); + } + else if (!strncmp(value, "stepping\t: ", 10)) { + sscanf(value, "stepping\t: %u", + &cpu_info->stepping); + + /* Exit -> all values must have been set */ + if (cpu_info->vendor == X86_VENDOR_UNKNOWN || + cpu_info->family == unknown || + cpu_info->model == unknown || + cpu_info->stepping == unknown) { + ret = -EINVAL; + goto out; + } + + ret = 0; + goto out; + } + } + ret = -ENODEV; +out: + fclose(fp); + /* Get some useful CPU capabilities from cpuid */ + if (cpu_info->vendor != X86_VENDOR_AMD && + cpu_info->vendor != X86_VENDOR_INTEL) + return ret; + + cpuid_level = cpuid_eax(0); + ext_cpuid_level = cpuid_eax(0x80000000); + + /* Invariant TSC */ + if (ext_cpuid_level >= 0x80000007 && + (cpuid_edx(0x80000007) & (1 << 8))) + cpu_info->caps |= CPUPOWER_CAP_INV_TSC; + + /* Aperf/Mperf registers support */ + if (cpuid_level >= 6 && (cpuid_ecx(6) & 0x1)) + cpu_info->caps |= CPUPOWER_CAP_APERF; + + /* AMD Boost state enable/disable register */ + if (cpu_info->vendor == X86_VENDOR_AMD) { + if (ext_cpuid_level >= 0x80000007 && + (cpuid_edx(0x80000007) & (1 << 9))) + cpu_info->caps |= CPUPOWER_CAP_AMD_CBP; + } + + /* Intel's perf-bias MSR support */ + if (cpu_info->vendor == X86_VENDOR_INTEL) { + if (cpuid_level >= 6 && (cpuid_ecx(6) & (1 << 3))) + cpu_info->caps |= CPUPOWER_CAP_PERF_BIAS; + } + + /* printf("ID: %u - Extid: 0x%x - Caps: 0x%llx\n", + cpuid_level, ext_cpuid_level, cpu_info->caps); + */ + return ret; +} |