xref: /linux/arch/arm/include/asm/fixmap.h (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_FIXMAP_H
3 #define _ASM_FIXMAP_H
4 
5 #define FIXADDR_START		0xffc00000UL
6 #define FIXADDR_END		0xfff00000UL
7 #define FIXADDR_TOP		(FIXADDR_END - PAGE_SIZE)
8 
9 #include <asm/kmap_types.h>
10 #include <asm/pgtable.h>
11 
12 enum fixed_addresses {
13 	FIX_EARLYCON_MEM_BASE,
14 	__end_of_permanent_fixed_addresses,
15 
16 	FIX_KMAP_BEGIN = __end_of_permanent_fixed_addresses,
17 	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
18 
19 	/* Support writing RO kernel text via kprobes, jump labels, etc. */
20 	FIX_TEXT_POKE0,
21 	FIX_TEXT_POKE1,
22 
23 	__end_of_fixmap_region,
24 
25 	/*
26 	 * Share the kmap() region with early_ioremap(): this is guaranteed
27 	 * not to clash since early_ioremap() is only available before
28 	 * paging_init(), and kmap() only after.
29 	 */
30 #define NR_FIX_BTMAPS		32
31 #define FIX_BTMAPS_SLOTS	7
32 #define TOTAL_FIX_BTMAPS	(NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
33 
34 	FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
35 	FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
36 	__end_of_early_ioremap_region
37 };
38 
39 static const enum fixed_addresses __end_of_fixed_addresses =
40 	__end_of_fixmap_region > __end_of_early_ioremap_region ?
41 	__end_of_fixmap_region : __end_of_early_ioremap_region;
42 
43 #define FIXMAP_PAGE_COMMON	(L_PTE_YOUNG | L_PTE_PRESENT | L_PTE_XN | L_PTE_DIRTY)
44 
45 #define FIXMAP_PAGE_NORMAL	(pgprot_kernel | L_PTE_XN)
46 #define FIXMAP_PAGE_RO		(FIXMAP_PAGE_NORMAL | L_PTE_RDONLY)
47 
48 /* Used by set_fixmap_(io|nocache), both meant for mapping a device */
49 #define FIXMAP_PAGE_IO		(FIXMAP_PAGE_COMMON | L_PTE_MT_DEV_SHARED | L_PTE_SHARED)
50 #define FIXMAP_PAGE_NOCACHE	FIXMAP_PAGE_IO
51 
52 #define __early_set_fixmap	__set_fixmap
53 
54 #ifdef CONFIG_MMU
55 
56 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
57 void __init early_fixmap_init(void);
58 
59 #include <asm-generic/fixmap.h>
60 
61 #else
62 
63 static inline void early_fixmap_init(void) { }
64 
65 #endif
66 #endif
67