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#include <asm/pgtable-prot.h>
24
25/*
26 * Here we define all the compile-time 'special' virtual
27 * addresses. The point is to have a constant address at
28 * compile time, but to set the physical address only
29 * in the boot process.
30 *
31 * Each enum increment in these 'compile-time allocated'
32 * memory buffers is page-sized. Use set_fixmap(idx,phys)
33 * to associate physical memory with a fixmap index.
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
54#ifdef CONFIG_ACPI_APEI_GHES
55	/* Used for GHES mapping from assorted contexts */
56	FIX_APEI_GHES_IRQ,
57	FIX_APEI_GHES_SEA,
58#ifdef CONFIG_ARM_SDE_INTERFACE
59	FIX_APEI_GHES_SDEI_NORMAL,
60	FIX_APEI_GHES_SDEI_CRITICAL,
61#endif
62#endif /* CONFIG_ACPI_APEI_GHES */
63
64#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
65	FIX_ENTRY_TRAMP_TEXT3,
66	FIX_ENTRY_TRAMP_TEXT2,
67	FIX_ENTRY_TRAMP_TEXT1,
68	FIX_ENTRY_TRAMP_DATA,
69#define TRAMP_VALIAS		(__fix_to_virt(FIX_ENTRY_TRAMP_TEXT1))
70#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
71	__end_of_permanent_fixed_addresses,
72
73	/*
74	 * Temporary boot-time mappings, used by early_ioremap(),
75	 * before ioremap() is functional.
76	 */
77#define NR_FIX_BTMAPS		(SZ_256K / PAGE_SIZE)
78#define FIX_BTMAPS_SLOTS	7
79#define TOTAL_FIX_BTMAPS	(NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
80
81	FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
82	FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
83
84	/*
85	 * Used for kernel page table creation, so unmapped memory may be used
86	 * for tables.
87	 */
88	FIX_PTE,
89	FIX_PMD,
90	FIX_PUD,
91	FIX_PGD,
92
93	__end_of_fixed_addresses
94};
95
96#define FIXADDR_SIZE	(__end_of_permanent_fixed_addresses << PAGE_SHIFT)
97#define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)
98
99#define FIXMAP_PAGE_IO     __pgprot(PROT_DEVICE_nGnRE)
100
101void __init early_fixmap_init(void);
102
103#define __early_set_fixmap __set_fixmap
104
105#define __late_set_fixmap __set_fixmap
106#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
107
108extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
109
110#include <asm-generic/fixmap.h>
111
112#endif /* !__ASSEMBLY__ */
113#endif /* _ASM_ARM64_FIXMAP_H */
114