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/math.h>
21#include <linux/sizes.h>
22#include <asm/boot.h>
23#include <asm/page.h>
24#include <asm/pgtable-prot.h>
25
26/*
27 * Here we define all the compile-time 'special' virtual
28 * addresses. The point is to have a constant address at
29 * compile time, but to set the physical address only
30 * in the boot process.
31 *
32 * Each enum increment in these 'compile-time allocated'
33 * memory buffers is page-sized. Use set_fixmap(idx,phys)
34 * to associate physical memory with a fixmap index.
35 */
36enum fixed_addresses {
37	FIX_HOLE,
38
39	/*
40	 * Reserve a virtual window for the FDT that is a page bigger than the
41	 * maximum supported size. The additional space ensures that any FDT
42	 * that does not exceed MAX_FDT_SIZE can be mapped regardless of
43	 * whether it crosses any page boundary.
44	 */
45	FIX_FDT_END,
46	FIX_FDT = FIX_FDT_END + DIV_ROUND_UP(MAX_FDT_SIZE, PAGE_SIZE) + 1,
47
48	FIX_EARLYCON_MEM_BASE,
49	FIX_TEXT_POKE0,
50
51#ifdef CONFIG_ACPI_APEI_GHES
52	/* Used for GHES mapping from assorted contexts */
53	FIX_APEI_GHES_IRQ,
54	FIX_APEI_GHES_SEA,
55#ifdef CONFIG_ARM_SDE_INTERFACE
56	FIX_APEI_GHES_SDEI_NORMAL,
57	FIX_APEI_GHES_SDEI_CRITICAL,
58#endif
59#endif /* CONFIG_ACPI_APEI_GHES */
60
61#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
62#ifdef CONFIG_RELOCATABLE
63	FIX_ENTRY_TRAMP_TEXT4,	/* one extra slot for the data page */
64#endif
65	FIX_ENTRY_TRAMP_TEXT3,
66	FIX_ENTRY_TRAMP_TEXT2,
67	FIX_ENTRY_TRAMP_TEXT1,
68#define TRAMP_VALIAS		(__fix_to_virt(FIX_ENTRY_TRAMP_TEXT1))
69#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
70	__end_of_permanent_fixed_addresses,
71
72	/*
73	 * Temporary boot-time mappings, used by early_ioremap(),
74	 * before ioremap() is functional.
75	 */
76#define NR_FIX_BTMAPS		(SZ_256K / PAGE_SIZE)
77#define FIX_BTMAPS_SLOTS	7
78#define TOTAL_FIX_BTMAPS	(NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
79
80	FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
81	FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
82
83	/*
84	 * Used for kernel page table creation, so unmapped memory may be used
85	 * for tables.
86	 */
87	FIX_PTE,
88	FIX_PMD,
89	FIX_PUD,
90	FIX_P4D,
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#define FIXADDR_TOT_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
99#define FIXADDR_TOT_START	(FIXADDR_TOP - FIXADDR_TOT_SIZE)
100
101#define FIXMAP_PAGE_IO     __pgprot(PROT_DEVICE_nGnRE)
102
103void __init early_fixmap_init(void);
104
105#define __early_set_fixmap __set_fixmap
106
107#define __late_set_fixmap __set_fixmap
108#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
109
110extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
111
112#include <asm-generic/fixmap.h>
113
114#endif /* !__ASSEMBLY__ */
115#endif /* _ASM_ARM64_FIXMAP_H */
116