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path: root/tools/power/cpupower/utils/helpers/cpuid.c
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Diffstat (limited to 'tools/power/cpupower/utils/helpers/cpuid.c')
-rw-r--r--tools/power/cpupower/utils/helpers/cpuid.c145
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 00000000000..71021f3bb69
--- /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;
+}