arch/arm/include/asm/efi.h

/*
 * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef __ASM_ARM_EFI_H
#define __ASM_ARM_EFI_H

#include <asm/cacheflush.h>
#include <asm/cachetype.h>
#include <asm/early_ioremap.h>
#include <asm/fixmap.h>
#include <asm/highmem.h>
#include <asm/mach/map.h>
#include <asm/mmu_context.h>
#include <asm/pgtable.h>

#ifdef CONFIG_EFI
void efi_init(void);

int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);

#define efi_call_virt(f, ...)						\
({									\
	efi_##f##_t *__f;						\
	efi_status_t __s;						\
									\
	efi_virtmap_load();						\
	__f = efi.systab->runtime->f;					\
	__s = __f(__VA_ARGS__);						\
	efi_virtmap_unload();						\
	__s;								\
})

#define __efi_call_virt(f, ...)						\
({									\
	efi_##f##_t *__f;						\
									\
	efi_virtmap_load();						\
	__f = efi.systab->runtime->f;					\
	__f(__VA_ARGS__);						\
	efi_virtmap_unload();						\
})

static inline void efi_set_pgd(struct mm_struct *mm)
{
	check_and_switch_context(mm, NULL);
}

void efi_virtmap_load(void);
void efi_virtmap_unload(void);

#else
#define efi_init()
#endif /* CONFIG_EFI */

/* arch specific definitions used by the stub code */

#define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__)

/*
 * A reasonable upper bound for the uncompressed kernel size is 32 MBytes,
 * so we will reserve that amount of memory. We have no easy way to tell what
 * the actuall size of code + data the uncompressed kernel will use.
 * If this is insufficient, the decompressor will relocate itself out of the
 * way before performing the decompression.
 */
#define MAX_UNCOMP_KERNEL_SIZE	SZ_32M

/*
 * The kernel zImage should preferably be located between 32 MB and 128 MB
 * from the base of DRAM. The min address leaves space for a maximal size
 * uncompressed image, and the max address is due to how the zImage decompressor
 * picks a destination address.
 */
#define ZIMAGE_OFFSET_LIMIT	SZ_128M
#define MIN_ZIMAGE_OFFSET	MAX_UNCOMP_KERNEL_SIZE
#define MAX_FDT_OFFSET		ZIMAGE_OFFSET_LIMIT

#endif /* _ASM_ARM_EFI_H */