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-rw-r--r--arch/x86/kernel/cpu/match.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c
new file mode 100644
index 000000000000..5502b289341b
--- /dev/null
+++ b/arch/x86/kernel/cpu/match.c
@@ -0,0 +1,91 @@
+#include <asm/cpu_device_id.h>
+#include <asm/processor.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+/**
+ * x86_match_cpu - match current CPU again an array of x86_cpu_ids
+ * @match: Pointer to array of x86_cpu_ids. Last entry terminated with
+ * {}.
+ *
+ * Return the entry if the current CPU matches the entries in the
+ * passed x86_cpu_id match table. Otherwise NULL. The match table
+ * contains vendor (X86_VENDOR_*), family, model and feature bits or
+ * respective wildcard entries.
+ *
+ * A typical table entry would be to match a specific CPU
+ * { X86_VENDOR_INTEL, 6, 0x12 }
+ * or to match a specific CPU feature
+ * { X86_FEATURE_MATCH(X86_FEATURE_FOOBAR) }
+ *
+ * Fields can be wildcarded with %X86_VENDOR_ANY, %X86_FAMILY_ANY,
+ * %X86_MODEL_ANY, %X86_FEATURE_ANY or 0 (except for vendor)
+ *
+ * Arrays used to match for this should also be declared using
+ * MODULE_DEVICE_TABLE(x86_cpu, ...)
+ *
+ * This always matches against the boot cpu, assuming models and features are
+ * consistent over all CPUs.
+ */
+const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match)
+{
+ const struct x86_cpu_id *m;
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+
+ for (m = match; m->vendor | m->family | m->model | m->feature; m++) {
+ if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor)
+ continue;
+ if (m->family != X86_FAMILY_ANY && c->x86 != m->family)
+ continue;
+ if (m->model != X86_MODEL_ANY && c->x86_model != m->model)
+ continue;
+ if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature))
+ continue;
+ return m;
+ }
+ return NULL;
+}
+EXPORT_SYMBOL(x86_match_cpu);
+
+ssize_t arch_print_cpu_modalias(struct device *dev,
+ struct device_attribute *attr,
+ char *bufptr)
+{
+ int size = PAGE_SIZE;
+ int i, n;
+ char *buf = bufptr;
+
+ n = snprintf(buf, size, "x86cpu:vendor:%04X:family:%04X:"
+ "model:%04X:feature:",
+ boot_cpu_data.x86_vendor,
+ boot_cpu_data.x86,
+ boot_cpu_data.x86_model);
+ size -= n;
+ buf += n;
+ size -= 1;
+ for (i = 0; i < NCAPINTS*32; i++) {
+ if (boot_cpu_has(i)) {
+ n = snprintf(buf, size, ",%04X", i);
+ if (n >= size) {
+ WARN(1, "x86 features overflow page\n");
+ break;
+ }
+ size -= n;
+ buf += n;
+ }
+ }
+ *buf++ = '\n';
+ return buf - bufptr;
+}
+
+int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (buf) {
+ arch_print_cpu_modalias(NULL, NULL, buf);
+ add_uevent_var(env, "MODALIAS=%s", buf);
+ kfree(buf);
+ }
+ return 0;
+}