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 <linux/sizes.h>
21#include <asm/boot.h>
22#include <asm/page.h>
23
24/*
25 * Here we define all the compile-time 'special' virtual
26 * addresses. The point is to have a constant address at
27 * compile time, but to set the physical address only
28 * in the boot process.
29 *
30 * These 'compile-time allocated' memory buffers are
31 * page-sized. Use set_fixmap(idx,phys) to associate
32 * physical memory with fixmap indices.
33 *
34 */
35enum fixed_addresses {
36	FIX_HOLE,
37
38	/*
39	 * Reserve a virtual window for the FDT that is 2 MB larger than the
40	 * maximum supported size, and put it at the top of the fixmap region.
41	 * The additional space ensures that any FDT that does not exceed
42	 * MAX_FDT_SIZE can be mapped regardless of whether it crosses any
43	 * 2 MB alignment boundaries.
44	 *
45	 * Keep this at the top so it remains 2 MB aligned.
46	 */
47#define FIX_FDT_SIZE		(MAX_FDT_SIZE + SZ_2M)
48	FIX_FDT_END,
49	FIX_FDT = FIX_FDT_END + FIX_FDT_SIZE / PAGE_SIZE - 1,
50
51	FIX_EARLYCON_MEM_BASE,
52	FIX_TEXT_POKE0,
53	__end_of_permanent_fixed_addresses,
54
55	/*
56	 * Temporary boot-time mappings, used by early_ioremap(),
57	 * before ioremap() is functional.
58	 */
59#define NR_FIX_BTMAPS		(SZ_256K / PAGE_SIZE)
60#define FIX_BTMAPS_SLOTS	7
61#define TOTAL_FIX_BTMAPS	(NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
62
63	FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
64	FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
65	__end_of_fixed_addresses
66};
67
68#define FIXADDR_SIZE	(__end_of_permanent_fixed_addresses << PAGE_SHIFT)
69#define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)
70
71#define FIXMAP_PAGE_IO     __pgprot(PROT_DEVICE_nGnRE)
72
73void __init early_fixmap_init(void);
74
75#define __early_set_fixmap __set_fixmap
76
77#define __late_set_fixmap __set_fixmap
78#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
79
80extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
81
82#include <asm-generic/fixmap.h>
83
84#endif /* !__ASSEMBLY__ */
85#endif /* _ASM_ARM64_FIXMAP_H */
86