xref: /openbmc/linux/arch/arm/include/asm/efi.h (revision a8fe58ce)
1 /*
2  * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #ifndef __ASM_ARM_EFI_H
10 #define __ASM_ARM_EFI_H
11 
12 #include <asm/cacheflush.h>
13 #include <asm/cachetype.h>
14 #include <asm/early_ioremap.h>
15 #include <asm/fixmap.h>
16 #include <asm/highmem.h>
17 #include <asm/mach/map.h>
18 #include <asm/mmu_context.h>
19 #include <asm/pgtable.h>
20 
21 #ifdef CONFIG_EFI
22 void efi_init(void);
23 
24 int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
25 
26 #define efi_call_virt(f, ...)						\
27 ({									\
28 	efi_##f##_t *__f;						\
29 	efi_status_t __s;						\
30 									\
31 	efi_virtmap_load();						\
32 	__f = efi.systab->runtime->f;					\
33 	__s = __f(__VA_ARGS__);						\
34 	efi_virtmap_unload();						\
35 	__s;								\
36 })
37 
38 #define __efi_call_virt(f, ...)						\
39 ({									\
40 	efi_##f##_t *__f;						\
41 									\
42 	efi_virtmap_load();						\
43 	__f = efi.systab->runtime->f;					\
44 	__f(__VA_ARGS__);						\
45 	efi_virtmap_unload();						\
46 })
47 
48 static inline void efi_set_pgd(struct mm_struct *mm)
49 {
50 	check_and_switch_context(mm, NULL);
51 }
52 
53 void efi_virtmap_load(void);
54 void efi_virtmap_unload(void);
55 
56 #else
57 #define efi_init()
58 #endif /* CONFIG_EFI */
59 
60 /* arch specific definitions used by the stub code */
61 
62 #define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__)
63 
64 /*
65  * A reasonable upper bound for the uncompressed kernel size is 32 MBytes,
66  * so we will reserve that amount of memory. We have no easy way to tell what
67  * the actuall size of code + data the uncompressed kernel will use.
68  * If this is insufficient, the decompressor will relocate itself out of the
69  * way before performing the decompression.
70  */
71 #define MAX_UNCOMP_KERNEL_SIZE	SZ_32M
72 
73 /*
74  * The kernel zImage should preferably be located between 32 MB and 128 MB
75  * from the base of DRAM. The min address leaves space for a maximal size
76  * uncompressed image, and the max address is due to how the zImage decompressor
77  * picks a destination address.
78  */
79 #define ZIMAGE_OFFSET_LIMIT	SZ_128M
80 #define MIN_ZIMAGE_OFFSET	MAX_UNCOMP_KERNEL_SIZE
81 #define MAX_FDT_OFFSET		ZIMAGE_OFFSET_LIMIT
82 
83 #endif /* _ASM_ARM_EFI_H */
84