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1/*
2 * fixmap.h: compile-time virtual memory allocation
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 1998 Ingo Molnar
9 * Copyright (C) 2013 Mark Salter <msalter@redhat.com>
10 *
11 * Adapted from arch/x86 version.
12 *
13 */
14
15#ifndef _ASM_ARM64_FIXMAP_H
16#define _ASM_ARM64_FIXMAP_H
17
18#ifndef __ASSEMBLY__
19#include <linux/kernel.h>
20#include <asm/boot.h>
21#include <asm/page.h>
22
23/*
24 * Here we define all the compile-time 'special' virtual
25 * addresses. The point is to have a constant address at
26 * compile time, but to set the physical address only
27 * in the boot process.
28 *
29 * These 'compile-time allocated' memory buffers are
30 * page-sized. Use set_fixmap(idx,phys) to associate
31 * physical memory with fixmap indices.
32 *
33 */
34enum fixed_addresses {
35 FIX_HOLE,
36
37 /*
38 * Reserve a virtual window for the FDT that is 2 MB larger than the
39 * maximum supported size, and put it at the top of the fixmap region.
40 * The additional space ensures that any FDT that does not exceed
41 * MAX_FDT_SIZE can be mapped regardless of whether it crosses any
42 * 2 MB alignment boundaries.
43 *
44 * Keep this at the top so it remains 2 MB aligned.
45 */
46#define FIX_FDT_SIZE (MAX_FDT_SIZE + SZ_2M)
47 FIX_FDT_END,
48 FIX_FDT = FIX_FDT_END + FIX_FDT_SIZE / PAGE_SIZE - 1,
49
50 FIX_EARLYCON_MEM_BASE,
51 FIX_TEXT_POKE0,
52 __end_of_permanent_fixed_addresses,
53
54 /*
55 * Temporary boot-time mappings, used by early_ioremap(),
56 * before ioremap() is functional.
57 */
58#ifdef CONFIG_ARM64_64K_PAGES
59#define NR_FIX_BTMAPS 4
60#else
61#define NR_FIX_BTMAPS 64
62#endif
63#define FIX_BTMAPS_SLOTS 7
64#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
65
66 FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
67 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
68 __end_of_fixed_addresses
69};
70
71#define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
72#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
73
74#define FIXMAP_PAGE_IO __pgprot(PROT_DEVICE_nGnRE)
75
76void __init early_fixmap_init(void);
77
78#define __early_set_fixmap __set_fixmap
79
80#define __late_set_fixmap __set_fixmap
81#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
82
83extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
84
85#include <asm-generic/fixmap.h>
86
87#endif /* !__ASSEMBLY__ */
88#endif /* _ASM_ARM64_FIXMAP_H */