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 * These 'compile-time allocated' memory buffers are
32 * page-sized. Use set_fixmap(idx,phys) to associate
33 * physical memory with fixmap indices.
34 *
35 */
36 enum fixed_addresses {
37 FIX_HOLE,
38
39 /*
40 * Reserve a virtual window for the FDT that is 2 MB larger than the
41 * maximum supported size, and put it at the top of the fixmap region.
42 * The additional space ensures that any FDT that does not exceed
43 * MAX_FDT_SIZE can be mapped regardless of whether it crosses any
44 * 2 MB alignment boundaries.
45 *
46 * Keep this at the top so it remains 2 MB aligned.
47 */
48 #define FIX_FDT_SIZE (MAX_FDT_SIZE + SZ_2M)
49 FIX_FDT_END,
50 FIX_FDT = FIX_FDT_END + FIX_FDT_SIZE / PAGE_SIZE - 1,
51
52 FIX_EARLYCON_MEM_BASE,
53 FIX_TEXT_POKE0,
54
55 #ifdef CONFIG_ACPI_APEI_GHES
56 /* Used for GHES mapping from assorted contexts */
57 FIX_APEI_GHES_IRQ,
58 FIX_APEI_GHES_SEA,
59 #ifdef CONFIG_ARM_SDE_INTERFACE
60 FIX_APEI_GHES_SDEI_NORMAL,
61 FIX_APEI_GHES_SDEI_CRITICAL,
62 #endif
63 #endif /* CONFIG_ACPI_APEI_GHES */
64
65 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
66 FIX_ENTRY_TRAMP_DATA,
67 FIX_ENTRY_TRAMP_TEXT,
68 #define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT))
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_PGD,
91
92 __end_of_fixed_addresses
93 };
94
95 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
96 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
97
98 #define FIXMAP_PAGE_IO __pgprot(PROT_DEVICE_nGnRE)
99
100 void __init early_fixmap_init(void);
101
102 #define __early_set_fixmap __set_fixmap
103
104 #define __late_set_fixmap __set_fixmap
105 #define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
106
107 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
108
109 #include <asm-generic/fixmap.h>
110
111 #endif /* !__ASSEMBLY__ */
112 #endif /* _ASM_ARM64_FIXMAP_H */