arch/x86/include/asm/realmode.h

Source file repositories/reference/linux-study-clean/arch/x86/include/asm/realmode.h

File Facts

System
Linux kernel
Corpus path
arch/x86/include/asm/realmode.h
Extension
.h
Size
2170 bytes
Lines
101
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct real_mode_header {
	u32	text_start;
	u32	ro_end;
	/* SMP trampoline */
	u32	trampoline_start;
	u32	trampoline_header;
#ifdef CONFIG_AMD_MEM_ENCRYPT
	u32	sev_es_trampoline_start;
#endif
#ifdef CONFIG_X86_64
	u32	trampoline_start64;
	u32	trampoline_pgd;
#endif
	/* ACPI S3 wakeup */
#ifdef CONFIG_ACPI_SLEEP
	u32	wakeup_start;
	u32	wakeup_header;
#endif
	/* APM/BIOS reboot */
	u32	machine_real_restart_asm;
#ifdef CONFIG_X86_64
	u32	machine_real_restart_seg;
#endif
};

/* This must match data at realmode/rm/trampoline_{32,64}.S */
struct trampoline_header {
#ifdef CONFIG_X86_32
	u32 start;
	u16 gdt_pad;
	u16 gdt_limit;
	u32 gdt_base;
#else
	u64 start;
	u64 efer;
	u32 cr4;
	u32 flags;
	u32 lock;
#endif
};

extern struct real_mode_header *real_mode_header;
extern unsigned char real_mode_blob_end[];

extern unsigned long initial_code;
extern unsigned long initial_stack;
#ifdef CONFIG_AMD_MEM_ENCRYPT
extern unsigned long initial_vc_handler;
#endif

extern u32 *trampoline_lock;

extern unsigned char real_mode_blob[];
extern unsigned char real_mode_relocs[];

#ifdef CONFIG_X86_32
extern unsigned char startup_32_smp[];
extern unsigned char boot_gdt[];
#else
extern unsigned char secondary_startup_64[];
extern unsigned char secondary_startup_64_no_verify[];
#endif

static __always_inline size_t real_mode_size_needed(void)
{
	if (real_mode_header)
		return 0;	/* already allocated. */

	return ALIGN(real_mode_blob_end - real_mode_blob, PAGE_SIZE);
}

static inline void set_real_mode_mem(phys_addr_t mem)
{
	real_mode_header = (struct real_mode_header *) __va(mem);
}

void reserve_real_mode(void);
void load_trampoline_pgtable(void);
void init_real_mode(void);

#endif /* __ASSEMBLER__ */

#endif /* _ARCH_X86_REALMODE_H */

Annotation

Implementation Notes