CPU Name identification

src/arch/x86/init.c

@@ -8,6 +8,7 @@
 #include <stdint.h>
 #include <arch/x86.h>
 #include <kernel.h>
+#include <mem/utils.h>
 
 /*
  * x86_overwrite_pat - Set PAT to WC
@@ -41,6 +42,52 @@ static void x86_overwrite_pat()
 void x86_arch_init()
 {
     x86_overwrite_pat();
+    x86_cpu_identification();
     idt_init();
     gdt_init();
+}
+
+/*
+ * cpu_supports_brandstring - Does the CPU support brand strings?
+ *
+ * Return:
+ * true  - if it does
+ * false - if it doesn't
+*/
+bool cpu_supports_brandstring() {
+    uint32_t eax, ebx, ecx, edx;
+    cpuid(0x80000000, &eax, &ebx, &ecx, &edx);
+
+    if (eax < 0x80000004) {
+        return false;
+    } else {
+        return true;
+    }
+}
+
+/*
+ * x86_cpu_idenfitication - get info about the CPU
+ *
+ * This function displays the CPU vendor name or the
+ * extended "brand string" if it's supported, on
+ * debug output.
+*/
+void x86_cpu_identification()
+{
+    if (cpu_supports_brandstring()) {
+        uint32_t regs[12];
+        // Some CPUs don't return null-terminated values so we do it as a failsafe default
+        char str[sizeof(regs)+1] = {0};
+        cpuid(0x80000002, &regs[0], &regs[1], &regs[2], &regs[3]);
+        cpuid(0x80000003, &regs[4], &regs[5], &regs[6], &regs[7]);
+        cpuid(0x80000004, &regs[8], &regs[9], &regs[10], &regs[11]);
+
+        memcpy(str, regs, sizeof(regs));
+        str[sizeof(regs)] = '\0';
+        DEBUG("CPU: %s", str);
+    } else {
+        char vendor_string[13] = {0};
+        cpuid_get_vendor_string(vendor_string);
+        DEBUG("CPU vendor is: %s", vendor_string);
+    }
 }