Kernel: Pull apart CPU.h

This does not add any functional changes

Kernel/Arch/x86/CPUID.h

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Types.h>
+
+namespace Kernel {
+
+class CPUID {
+public:
+    explicit CPUID(u32 function) { asm volatile("cpuid"
+                                                : "=a"(m_eax), "=b"(m_ebx), "=c"(m_ecx), "=d"(m_edx)
+                                                : "a"(function), "c"(0)); }
+    u32 eax() const { return m_eax; }
+    u32 ebx() const { return m_ebx; }
+    u32 ecx() const { return m_ecx; }
+    u32 edx() const { return m_edx; }
+
+private:
+    u32 m_eax { 0xffffffff };
+    u32 m_ebx { 0xffffffff };
+    u32 m_ecx { 0xffffffff };
+    u32 m_edx { 0xffffffff };
+};
+
+// FIXME: This can't hold every CPU feature as-is.
+enum class CPUFeature : u32 {
+    NX = (1 << 0),
+    PAE = (1 << 1),
+    PGE = (1 << 2),
+    RDRAND = (1 << 3),
+    RDSEED = (1 << 4),
+    SMAP = (1 << 5),
+    SMEP = (1 << 6),
+    SSE = (1 << 7),
+    TSC = (1 << 8),
+    RDTSCP = (1 << 9),
+    CONSTANT_TSC = (1 << 10),
+    NONSTOP_TSC = (1 << 11),
+    UMIP = (1 << 12),
+    SEP = (1 << 13),
+    SYSCALL = (1 << 14),
+    MMX = (1 << 15),
+    SSE2 = (1 << 16),
+    SSE3 = (1 << 17),
+    SSSE3 = (1 << 18),
+    SSE4_1 = (1 << 19),
+    SSE4_2 = (1 << 20),
+    XSAVE = (1 << 21),
+    AVX = (1 << 22),
+    FXSR = (1 << 23),
+};
+
+}