xref: /linux/arch/arm/include/asm/pgtable-nommu.h (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  *  arch/arm/include/asm/pgtable-nommu.h
4  *
5  *  Copyright (C) 1995-2002 Russell King
6  *  Copyright (C) 2004  Hyok S. Choi
7  */
8 #ifndef _ASMARM_PGTABLE_NOMMU_H
9 #define _ASMARM_PGTABLE_NOMMU_H
10 
11 #ifndef __ASSEMBLY__
12 
13 #include <linux/slab.h>
14 #include <asm/processor.h>
15 #include <asm/page.h>
16 
17 /*
18  * Trivial page table functions.
19  */
20 #define pgd_present(pgd)	(1)
21 #define pgd_none(pgd)		(0)
22 #define pgd_bad(pgd)		(0)
23 #define pgd_clear(pgdp)
24 #define kern_addr_valid(addr)	(1)
25 /* FIXME */
26 /*
27  * PMD_SHIFT determines the size of the area a second-level page table can map
28  * PGDIR_SHIFT determines what a third-level page table entry can map
29  */
30 #define PGDIR_SHIFT		21
31 
32 #define PGDIR_SIZE		(1UL << PGDIR_SHIFT)
33 #define PGDIR_MASK		(~(PGDIR_SIZE-1))
34 /* FIXME */
35 
36 #define PAGE_NONE	__pgprot(0)
37 #define PAGE_SHARED	__pgprot(0)
38 #define PAGE_COPY	__pgprot(0)
39 #define PAGE_READONLY	__pgprot(0)
40 #define PAGE_KERNEL	__pgprot(0)
41 
42 #define swapper_pg_dir ((pgd_t *) 0)
43 
44 
45 typedef pte_t *pte_addr_t;
46 
47 /*
48  * ZERO_PAGE is a global shared page that is always zero: used
49  * for zero-mapped memory areas etc..
50  */
51 #define ZERO_PAGE(vaddr)	(virt_to_page(0))
52 
53 /*
54  * Mark the prot value as uncacheable and unbufferable.
55  */
56 #define pgprot_noncached(prot)	(prot)
57 #define pgprot_writecombine(prot) (prot)
58 #define pgprot_device(prot)	(prot)
59 
60 
61 /*
62  * These would be in other places but having them here reduces the diffs.
63  */
64 extern unsigned int kobjsize(const void *objp);
65 
66 /*
67  * All 32bit addresses are effectively valid for vmalloc...
68  * Sort of meaningless for non-VM targets.
69  */
70 #define	VMALLOC_START	0UL
71 #define	VMALLOC_END	0xffffffffUL
72 
73 #define FIRST_USER_ADDRESS      0UL
74 
75 #else
76 
77 /*
78  * dummy tlb and user structures.
79  */
80 #define v3_tlb_fns	(0)
81 #define v4_tlb_fns	(0)
82 #define v4wb_tlb_fns	(0)
83 #define v4wbi_tlb_fns	(0)
84 #define v6wbi_tlb_fns	(0)
85 #define v7wbi_tlb_fns	(0)
86 
87 #define v3_user_fns	(0)
88 #define v4_user_fns	(0)
89 #define v4_mc_user_fns	(0)
90 #define v4wb_user_fns	(0)
91 #define v4wt_user_fns	(0)
92 #define v6_user_fns	(0)
93 #define xscale_mc_user_fns (0)
94 
95 #endif /*__ASSEMBLY__*/
96 
97 #endif /* _ASMARM_PGTABLE_H */
98