diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index da8f3caf2781..15a5f4f2ff0a 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -53,6 +53,9 @@ REALMODE_CFLAGS += -fno-stack-protector
 REALMODE_CFLAGS += -Wno-address-of-packed-member
 REALMODE_CFLAGS += $(cc_stack_align4)
 REALMODE_CFLAGS += $(CLANG_FLAGS)
+ifdef CONFIG_CC_IS_CLANG
+REALMODE_CFLAGS += -Wno-gnu
+endif
 export REALMODE_CFLAGS
 
 # BITS is used as extension for files which are available in a 32 bit
diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
index 18d15d1ce87d..f196b1d1ddf8 100644
--- a/arch/x86/boot/compressed/acpi.c
+++ b/arch/x86/boot/compressed/acpi.c
@@ -5,6 +5,8 @@
 #include "../string.h"
 #include "efi.h"
 
+#include <asm/bootparam.h>
+
 #include <linux/numa.h>
 
 /*
diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c
index c1bb180973ea..e162d7f59cc5 100644
--- a/arch/x86/boot/compressed/cmdline.c
+++ b/arch/x86/boot/compressed/cmdline.c
@@ -1,6 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "misc.h"
 
+#include <asm/bootparam.h>
+
 static unsigned long fs;
 static inline void set_fs(unsigned long seg)
 {
diff --git a/arch/x86/boot/compressed/efi.c b/arch/x86/boot/compressed/efi.c
index 6edd034b0b30..f2e50f9758e6 100644
--- a/arch/x86/boot/compressed/efi.c
+++ b/arch/x86/boot/compressed/efi.c
@@ -7,6 +7,8 @@
 
 #include "misc.h"
 
+#include <asm/bootparam.h>
+
 /**
  * efi_get_type - Given a pointer to boot_params, determine the type of EFI environment.
  *
diff --git a/arch/x86/boot/compressed/efi.h b/arch/x86/boot/compressed/efi.h
index 866c0af8b5b9..b22300970f97 100644
--- a/arch/x86/boot/compressed/efi.h
+++ b/arch/x86/boot/compressed/efi.h
@@ -97,15 +97,6 @@ typedef struct {
 	u32 tables;
 } efi_system_table_32_t;
 
-/* kexec external ABI */
-struct efi_setup_data {
-	u64 fw_vendor;
-	u64 __unused;
-	u64 tables;
-	u64 smbios;
-	u64 reserved[8];
-};
-
 struct efi_unaccepted_memory {
 	u32 version;
 	u32 unit_size;
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c
index 51f957b24ba7..c882e1f67af0 100644
--- a/arch/x86/boot/compressed/pgtable_64.c
+++ b/arch/x86/boot/compressed/pgtable_64.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "misc.h"
+#include <asm/bootparam.h>
 #include <asm/e820/types.h>
 #include <asm/processor.h>
 #include "pgtable.h"
diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c
index 9db630238034..97561eabfbef 100644
--- a/arch/x86/boot/compressed/sev.c
+++ b/arch/x86/boot/compressed/sev.c
@@ -12,6 +12,7 @@
  */
 #include "misc.h"
 
+#include <asm/bootparam.h>
 #include <asm/pgtable_types.h>
 #include <asm/sev.h>
 #include <asm/trapnr.h>
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index c4555b269a1b..1dc600fa3ba5 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -143,15 +143,6 @@ extern void efi_free_boot_services(void);
 void arch_efi_call_virt_setup(void);
 void arch_efi_call_virt_teardown(void);
 
-/* kexec external ABI */
-struct efi_setup_data {
-	u64 fw_vendor;
-	u64 __unused;
-	u64 tables;
-	u64 smbios;
-	u64 reserved[8];
-};
-
 extern u64 efi_setup;
 
 #ifdef CONFIG_EFI
@@ -418,8 +409,9 @@ extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
 				     void *buf, struct efi_mem_range *mem);
 
-#define arch_ima_efi_boot_mode	\
-	({ extern struct boot_params boot_params; boot_params.secure_boot; })
+extern enum efi_secureboot_mode __x86_ima_efi_boot_mode(void);
+
+#define arch_ima_efi_boot_mode	__x86_ima_efi_boot_mode()
 
 #ifdef CONFIG_EFI_RUNTIME_MAP
 int efi_get_runtime_map_size(void);
diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index c9f6a6c5de3c..91ca9a9ee3a2 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h
@@ -25,7 +25,6 @@
 
 #include <asm/page.h>
 #include <asm/ptrace.h>
-#include <asm/bootparam.h>
 
 struct kimage;
 
diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index b40c462b4af3..b3ab80a03365 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -10,7 +10,6 @@
 #include <linux/numa.h>
 #include <asm/io.h>
 #include <asm/memtype.h>
-#include <asm/x86_init.h>
 
 struct pci_sysdata {
 	int		domain;		/* PCI domain */
@@ -124,16 +123,4 @@ cpumask_of_pcibus(const struct pci_bus *bus)
 }
 #endif
 
-struct pci_setup_rom {
-	struct setup_data data;
-	uint16_t vendor;
-	uint16_t devid;
-	uint64_t pcilen;
-	unsigned long segment;
-	unsigned long bus;
-	unsigned long device;
-	unsigned long function;
-	uint8_t romdata[];
-};
-
 #endif /* _ASM_X86_PCI_H */
diff --git a/arch/x86/include/asm/setup_data.h b/arch/x86/include/asm/setup_data.h
new file mode 100644
index 000000000000..77c51111a893
--- /dev/null
+++ b/arch/x86/include/asm/setup_data.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_SETUP_DATA_H
+#define _ASM_X86_SETUP_DATA_H
+
+#include <uapi/asm/setup_data.h>
+
+#ifndef __ASSEMBLY__
+
+struct pci_setup_rom {
+	struct setup_data data;
+	uint16_t vendor;
+	uint16_t devid;
+	uint64_t pcilen;
+	unsigned long segment;
+	unsigned long bus;
+	unsigned long device;
+	unsigned long function;
+	uint8_t romdata[];
+};
+
+/* kexec external ABI */
+struct efi_setup_data {
+	u64 fw_vendor;
+	u64 __unused;
+	u64 tables;
+	u64 smbios;
+	u64 reserved[8];
+};
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_X86_SETUP_DATA_H */
diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
index f000635d6061..10f9f1b259c3 100644
--- a/arch/x86/include/asm/sev.h
+++ b/arch/x86/include/asm/sev.h
@@ -13,7 +13,6 @@
 
 #include <asm/insn.h>
 #include <asm/sev-common.h>
-#include <asm/bootparam.h>
 #include <asm/coco.h>
 
 #define GHCB_PROTOCOL_MIN	1ULL
@@ -22,6 +21,8 @@
 
 #define	VMGEXIT()			{ asm volatile("rep; vmmcall\n\r"); }
 
+struct boot_params;
+
 enum es_result {
 	ES_OK,			/* All good */
 	ES_UNSUPPORTED,		/* Requested operation not supported */
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index 9ca624749176..b89b40f250e6 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -2,8 +2,6 @@
 #ifndef _ASM_X86_PLATFORM_H
 #define _ASM_X86_PLATFORM_H
 
-#include <asm/bootparam.h>
-
 struct ghcb;
 struct mpc_bus;
 struct mpc_cpu;
diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
index 01d19fc22346..4a38e7917756 100644
--- a/arch/x86/include/uapi/asm/bootparam.h
+++ b/arch/x86/include/uapi/asm/bootparam.h
@@ -2,21 +2,7 @@
 #ifndef _ASM_X86_BOOTPARAM_H
 #define _ASM_X86_BOOTPARAM_H
 
-/* setup_data/setup_indirect types */
-#define SETUP_NONE			0
-#define SETUP_E820_EXT			1
-#define SETUP_DTB			2
-#define SETUP_PCI			3
-#define SETUP_EFI			4
-#define SETUP_APPLE_PROPERTIES		5
-#define SETUP_JAILHOUSE			6
-#define SETUP_CC_BLOB			7
-#define SETUP_IMA			8
-#define SETUP_RNG_SEED			9
-#define SETUP_ENUM_MAX			SETUP_RNG_SEED
-
-#define SETUP_INDIRECT			(1<<31)
-#define SETUP_TYPE_MAX			(SETUP_ENUM_MAX | SETUP_INDIRECT)
+#include <asm/setup_data.h>
 
 /* ram_size flags */
 #define RAMDISK_IMAGE_START_MASK	0x07FF
@@ -48,22 +34,6 @@
 #include <asm/ist.h>
 #include <video/edid.h>
 
-/* extensible setup data list node */
-struct setup_data {
-	__u64 next;
-	__u32 type;
-	__u32 len;
-	__u8 data[];
-};
-
-/* extensible setup indirect data node */
-struct setup_indirect {
-	__u32 type;
-	__u32 reserved;  /* Reserved, must be set to zero. */
-	__u64 len;
-	__u64 addr;
-};
-
 struct setup_header {
 	__u8	setup_sects;
 	__u16	root_flags;
@@ -136,51 +106,11 @@ struct efi_info {
  */
 #define E820_MAX_ENTRIES_ZEROPAGE 128
 
-/*
- * The E820 memory region entry of the boot protocol ABI:
- */
-struct boot_e820_entry {
-	__u64 addr;
-	__u64 size;
-	__u32 type;
-} __attribute__((packed));
-
 /*
  * Smallest compatible version of jailhouse_setup_data required by this kernel.
  */
 #define JAILHOUSE_SETUP_REQUIRED_VERSION	1
 
-/*
- * The boot loader is passing platform information via this Jailhouse-specific
- * setup data structure.
- */
-struct jailhouse_setup_data {
-	struct {
-		__u16	version;
-		__u16	compatible_version;
-	} __attribute__((packed)) hdr;
-	struct {
-		__u16	pm_timer_address;
-		__u16	num_cpus;
-		__u64	pci_mmconfig_base;
-		__u32	tsc_khz;
-		__u32	apic_khz;
-		__u8	standard_ioapic;
-		__u8	cpu_ids[255];
-	} __attribute__((packed)) v1;
-	struct {
-		__u32	flags;
-	} __attribute__((packed)) v2;
-} __attribute__((packed));
-
-/*
- * IMA buffer setup data information from the previous kernel during kexec
- */
-struct ima_setup_data {
-	__u64 addr;
-	__u64 size;
-} __attribute__((packed));
-
 /* The so-called "zeropage" */
 struct boot_params {
 	struct screen_info screen_info;			/* 0x000 */
diff --git a/arch/x86/include/uapi/asm/setup_data.h b/arch/x86/include/uapi/asm/setup_data.h
new file mode 100644
index 000000000000..b111b0c18544
--- /dev/null
+++ b/arch/x86/include/uapi/asm/setup_data.h
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_ASM_X86_SETUP_DATA_H
+#define _UAPI_ASM_X86_SETUP_DATA_H
+
+/* setup_data/setup_indirect types */
+#define SETUP_NONE			0
+#define SETUP_E820_EXT			1
+#define SETUP_DTB			2
+#define SETUP_PCI			3
+#define SETUP_EFI			4
+#define SETUP_APPLE_PROPERTIES		5
+#define SETUP_JAILHOUSE			6
+#define SETUP_CC_BLOB			7
+#define SETUP_IMA			8
+#define SETUP_RNG_SEED			9
+#define SETUP_ENUM_MAX			SETUP_RNG_SEED
+
+#define SETUP_INDIRECT			(1<<31)
+#define SETUP_TYPE_MAX			(SETUP_ENUM_MAX | SETUP_INDIRECT)
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+
+/* extensible setup data list node */
+struct setup_data {
+	__u64 next;
+	__u32 type;
+	__u32 len;
+	__u8 data[];
+};
+
+/* extensible setup indirect data node */
+struct setup_indirect {
+	__u32 type;
+	__u32 reserved;  /* Reserved, must be set to zero. */
+	__u64 len;
+	__u64 addr;
+};
+
+/*
+ * The E820 memory region entry of the boot protocol ABI:
+ */
+struct boot_e820_entry {
+	__u64 addr;
+	__u64 size;
+	__u32 type;
+} __attribute__((packed));
+
+/*
+ * The boot loader is passing platform information via this Jailhouse-specific
+ * setup data structure.
+ */
+struct jailhouse_setup_data {
+	struct {
+		__u16	version;
+		__u16	compatible_version;
+	} __attribute__((packed)) hdr;
+	struct {
+		__u16	pm_timer_address;
+		__u16	num_cpus;
+		__u64	pci_mmconfig_base;
+		__u32	tsc_khz;
+		__u32	apic_khz;
+		__u8	standard_ioapic;
+		__u8	cpu_ids[255];
+	} __attribute__((packed)) v1;
+	struct {
+		__u32	flags;
+	} __attribute__((packed)) v2;
+} __attribute__((packed));
+
+/*
+ * IMA buffer setup data information from the previous kernel during kexec
+ */
+struct ima_setup_data {
+	__u64 addr;
+	__u64 size;
+} __attribute__((packed));
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _UAPI_ASM_X86_SETUP_DATA_H */
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index d184c29398db..e74d0c4286c1 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -26,6 +26,7 @@
 #include <linux/vmalloc.h>
 #include <linux/memblock.h>
 
+#include <asm/bootparam.h>
 #include <asm/processor.h>
 #include <asm/hardirq.h>
 #include <asm/nmi.h>
diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
index ae79f9505298..a200bd72fadc 100644
--- a/arch/x86/kernel/sev-shared.c
+++ b/arch/x86/kernel/sev-shared.c
@@ -9,6 +9,8 @@
  * and is included directly into both code-bases.
  */
 
+#include <asm/setup_data.h>
+
 #ifndef __BOOT_COMPRESSED
 #define error(v)			pr_err(v)
 #define has_cpuflag(f)			boot_cpu_has(f)
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index e9f99c56f3ce..f090ec972d7b 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -950,3 +950,8 @@ umode_t efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n)
 	}
 	return attr->mode;
 }
+
+enum efi_secureboot_mode __x86_ima_efi_boot_mode(void)
+{
+	return boot_params.secure_boot;
+}
diff --git a/arch/x86/platform/pvh/enlighten.c b/arch/x86/platform/pvh/enlighten.c
index 00a92cb2c814..944e0290f2c0 100644
--- a/arch/x86/platform/pvh/enlighten.c
+++ b/arch/x86/platform/pvh/enlighten.c
@@ -3,6 +3,7 @@
 
 #include <xen/hvc-console.h>
 
+#include <asm/bootparam.h>
 #include <asm/io_apic.h>
 #include <asm/hypervisor.h>
 #include <asm/e820/api.h>
diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index ada3868c02c2..9e9db601bd52 100644
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c
@@ -4,6 +4,7 @@
 
 #include <xen/hvc-console.h>
 
+#include <asm/bootparam.h>
 #include <asm/io_apic.h>
 #include <asm/hypervisor.h>
 #include <asm/e820/api.h>
diff --git a/arch/x86/xen/vga.c b/arch/x86/xen/vga.c
index d97adab8420f..f7547807b0bd 100644
--- a/arch/x86/xen/vga.c
+++ b/arch/x86/xen/vga.c
@@ -2,7 +2,6 @@
 #include <linux/screen_info.h>
 #include <linux/init.h>
 
-#include <asm/bootparam.h>
 #include <asm/setup.h>
 
 #include <xen/interface/xen.h>