xref: /linux/arch/arm/include/asm/pgtable-nommu.h (revision 17cfcb68af3bc7d5e8ae08779b1853310a2949f3)
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 #define	pmd_offset(a, b)	((void *)0)
26 /* FIXME */
27 /*
28  * PMD_SHIFT determines the size of the area a second-level page table can map
29  * PGDIR_SHIFT determines what a third-level page table entry can map
30  */
31 #define PGDIR_SHIFT		21
32 
33 #define PGDIR_SIZE		(1UL << PGDIR_SHIFT)
34 #define PGDIR_MASK		(~(PGDIR_SIZE-1))
35 /* FIXME */
36 
37 #define PAGE_NONE	__pgprot(0)
38 #define PAGE_SHARED	__pgprot(0)
39 #define PAGE_COPY	__pgprot(0)
40 #define PAGE_READONLY	__pgprot(0)
41 #define PAGE_KERNEL	__pgprot(0)
42 
43 #define swapper_pg_dir ((pgd_t *) 0)
44 
45 #define __swp_type(x)		(0)
46 #define __swp_offset(x)		(0)
47 #define __swp_entry(typ,off)	((swp_entry_t) { ((typ) | ((off) << 7)) })
48 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
49 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
50 
51 
52 typedef pte_t *pte_addr_t;
53 
54 /*
55  * ZERO_PAGE is a global shared page that is always zero: used
56  * for zero-mapped memory areas etc..
57  */
58 #define ZERO_PAGE(vaddr)	(virt_to_page(0))
59 
60 /*
61  * Mark the prot value as uncacheable and unbufferable.
62  */
63 #define pgprot_noncached(prot)	(prot)
64 #define pgprot_writecombine(prot) (prot)
65 #define pgprot_device(prot)	(prot)
66 
67 
68 /*
69  * These would be in other places but having them here reduces the diffs.
70  */
71 extern unsigned int kobjsize(const void *objp);
72 
73 /*
74  * All 32bit addresses are effectively valid for vmalloc...
75  * Sort of meaningless for non-VM targets.
76  */
77 #define	VMALLOC_START	0UL
78 #define	VMALLOC_END	0xffffffffUL
79 
80 #define FIRST_USER_ADDRESS      0UL
81 
82 #include <asm-generic/pgtable.h>
83 
84 #else
85 
86 /*
87  * dummy tlb and user structures.
88  */
89 #define v3_tlb_fns	(0)
90 #define v4_tlb_fns	(0)
91 #define v4wb_tlb_fns	(0)
92 #define v4wbi_tlb_fns	(0)
93 #define v6wbi_tlb_fns	(0)
94 #define v7wbi_tlb_fns	(0)
95 
96 #define v3_user_fns	(0)
97 #define v4_user_fns	(0)
98 #define v4_mc_user_fns	(0)
99 #define v4wb_user_fns	(0)
100 #define v4wt_user_fns	(0)
101 #define v6_user_fns	(0)
102 #define xscale_mc_user_fns (0)
103 
104 #endif /*__ASSEMBLY__*/
105 
106 #endif /* _ASMARM_PGTABLE_H */
107