v4.19.13 snapshot.
diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
new file mode 100644
index 0000000..2b7cc53
--- /dev/null
+++ b/arch/x86/include/asm/microcode.h
@@ -0,0 +1,145 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_MICROCODE_H
+#define _ASM_X86_MICROCODE_H
+
+#include <asm/cpu.h>
+#include <linux/earlycpio.h>
+#include <linux/initrd.h>
+
+struct ucode_patch {
+	struct list_head plist;
+	void *data;		/* Intel uses only this one */
+	u32 patch_id;
+	u16 equiv_cpu;
+};
+
+extern struct list_head microcode_cache;
+
+struct cpu_signature {
+	unsigned int sig;
+	unsigned int pf;
+	unsigned int rev;
+};
+
+struct device;
+
+enum ucode_state {
+	UCODE_OK	= 0,
+	UCODE_NEW,
+	UCODE_UPDATED,
+	UCODE_NFOUND,
+	UCODE_ERROR,
+};
+
+struct microcode_ops {
+	enum ucode_state (*request_microcode_user) (int cpu,
+				const void __user *buf, size_t size);
+
+	enum ucode_state (*request_microcode_fw) (int cpu, struct device *,
+						  bool refresh_fw);
+
+	void (*microcode_fini_cpu) (int cpu);
+
+	/*
+	 * The generic 'microcode_core' part guarantees that
+	 * the callbacks below run on a target cpu when they
+	 * are being called.
+	 * See also the "Synchronization" section in microcode_core.c.
+	 */
+	enum ucode_state (*apply_microcode) (int cpu);
+	int (*collect_cpu_info) (int cpu, struct cpu_signature *csig);
+};
+
+struct ucode_cpu_info {
+	struct cpu_signature	cpu_sig;
+	int			valid;
+	void			*mc;
+};
+extern struct ucode_cpu_info ucode_cpu_info[];
+struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa);
+
+#ifdef CONFIG_MICROCODE_INTEL
+extern struct microcode_ops * __init init_intel_microcode(void);
+#else
+static inline struct microcode_ops * __init init_intel_microcode(void)
+{
+	return NULL;
+}
+#endif /* CONFIG_MICROCODE_INTEL */
+
+#ifdef CONFIG_MICROCODE_AMD
+extern struct microcode_ops * __init init_amd_microcode(void);
+extern void __exit exit_amd_microcode(void);
+#else
+static inline struct microcode_ops * __init init_amd_microcode(void)
+{
+	return NULL;
+}
+static inline void __exit exit_amd_microcode(void) {}
+#endif
+
+#define MAX_UCODE_COUNT 128
+
+#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
+#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
+#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
+#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
+#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
+#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
+#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
+
+#define CPUID_IS(a, b, c, ebx, ecx, edx)	\
+		(!((ebx ^ (a))|(edx ^ (b))|(ecx ^ (c))))
+
+/*
+ * In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
+ * x86_cpuid_vendor() gets vendor id for BSP.
+ *
+ * In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
+ * coding, we still use x86_cpuid_vendor() to get vendor id for AP.
+ *
+ * x86_cpuid_vendor() gets vendor information directly from CPUID.
+ */
+static inline int x86_cpuid_vendor(void)
+{
+	u32 eax = 0x00000000;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
+		return X86_VENDOR_INTEL;
+
+	if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
+		return X86_VENDOR_AMD;
+
+	return X86_VENDOR_UNKNOWN;
+}
+
+static inline unsigned int x86_cpuid_family(void)
+{
+	u32 eax = 0x00000001;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	return x86_family(eax);
+}
+
+#ifdef CONFIG_MICROCODE
+int __init microcode_init(void);
+extern void __init load_ucode_bsp(void);
+extern void load_ucode_ap(void);
+void reload_early_microcode(void);
+extern bool get_builtin_firmware(struct cpio_data *cd, const char *name);
+extern bool initrd_gone;
+#else
+static inline int __init microcode_init(void)			{ return 0; };
+static inline void __init load_ucode_bsp(void)			{ }
+static inline void load_ucode_ap(void)				{ }
+static inline void reload_early_microcode(void)			{ }
+static inline bool
+get_builtin_firmware(struct cpio_data *cd, const char *name)	{ return false; }
+#endif
+
+#endif /* _ASM_X86_MICROCODE_H */