xref: /openbmc/linux/arch/m68k/include/asm/pgtable_mm.h (revision 2c684d89)
1 #ifndef _M68K_PGTABLE_H
2 #define _M68K_PGTABLE_H
3 
4 #include <asm-generic/4level-fixup.h>
5 
6 #include <asm/setup.h>
7 
8 #ifndef __ASSEMBLY__
9 #include <asm/processor.h>
10 #include <linux/sched.h>
11 #include <linux/threads.h>
12 
13 /*
14  * This file contains the functions and defines necessary to modify and use
15  * the m68k page table tree.
16  */
17 
18 #include <asm/virtconvert.h>
19 
20 /* Certain architectures need to do special things when pte's
21  * within a page table are directly modified.  Thus, the following
22  * hook is made available.
23  */
24 #define set_pte(pteptr, pteval)					\
25 	do{							\
26 		*(pteptr) = (pteval);				\
27 	} while(0)
28 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
29 
30 
31 /* PMD_SHIFT determines the size of the area a second-level page table can map */
32 #ifdef CONFIG_SUN3
33 #define PMD_SHIFT       17
34 #else
35 #define PMD_SHIFT	22
36 #endif
37 #define PMD_SIZE	(1UL << PMD_SHIFT)
38 #define PMD_MASK	(~(PMD_SIZE-1))
39 
40 /* PGDIR_SHIFT determines what a third-level page table entry can map */
41 #ifdef CONFIG_SUN3
42 #define PGDIR_SHIFT     17
43 #elif defined(CONFIG_COLDFIRE)
44 #define PGDIR_SHIFT     22
45 #else
46 #define PGDIR_SHIFT	25
47 #endif
48 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
49 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
50 
51 /*
52  * entries per page directory level: the m68k is configured as three-level,
53  * so we do have PMD level physically.
54  */
55 #ifdef CONFIG_SUN3
56 #define PTRS_PER_PTE   16
57 #define __PAGETABLE_PMD_FOLDED
58 #define PTRS_PER_PMD   1
59 #define PTRS_PER_PGD   2048
60 #elif defined(CONFIG_COLDFIRE)
61 #define PTRS_PER_PTE	512
62 #define __PAGETABLE_PMD_FOLDED
63 #define PTRS_PER_PMD	1
64 #define PTRS_PER_PGD	1024
65 #else
66 #define PTRS_PER_PTE	1024
67 #define PTRS_PER_PMD	8
68 #define PTRS_PER_PGD	128
69 #endif
70 #define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
71 #define FIRST_USER_ADDRESS	0UL
72 
73 /* Virtual address region for use by kernel_map() */
74 #ifdef CONFIG_SUN3
75 #define KMAP_START     0x0DC00000
76 #define KMAP_END       0x0E000000
77 #elif defined(CONFIG_COLDFIRE)
78 #define KMAP_START	0xe0000000
79 #define KMAP_END	0xf0000000
80 #else
81 #define	KMAP_START	0xd0000000
82 #define	KMAP_END	0xf0000000
83 #endif
84 
85 #ifdef CONFIG_SUN3
86 extern unsigned long m68k_vmalloc_end;
87 #define VMALLOC_START 0x0f800000
88 #define VMALLOC_END m68k_vmalloc_end
89 #elif defined(CONFIG_COLDFIRE)
90 #define VMALLOC_START	0xd0000000
91 #define VMALLOC_END	0xe0000000
92 #else
93 /* Just any arbitrary offset to the start of the vmalloc VM area: the
94  * current 8MB value just means that there will be a 8MB "hole" after the
95  * physical memory until the kernel virtual memory starts.  That means that
96  * any out-of-bounds memory accesses will hopefully be caught.
97  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
98  * area for the same reason. ;)
99  */
100 #define VMALLOC_OFFSET	(8*1024*1024)
101 #define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
102 #define VMALLOC_END KMAP_START
103 #endif
104 
105 /* zero page used for uninitialized stuff */
106 extern void *empty_zero_page;
107 
108 /*
109  * ZERO_PAGE is a global shared page that is always zero: used
110  * for zero-mapped memory areas etc..
111  */
112 #define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
113 
114 /* number of bits that fit into a memory pointer */
115 #define BITS_PER_PTR			(8*sizeof(unsigned long))
116 
117 /* to align the pointer to a pointer address */
118 #define PTR_MASK			(~(sizeof(void*)-1))
119 
120 /* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */
121 /* 64-bit machines, beware!  SRB. */
122 #define SIZEOF_PTR_LOG2			       2
123 
124 extern void kernel_set_cachemode(void *addr, unsigned long size, int cmode);
125 
126 /*
127  * The m68k doesn't have any external MMU info: the kernel page
128  * tables contain all the necessary information.  The Sun3 does, but
129  * they are updated on demand.
130  */
131 static inline void update_mmu_cache(struct vm_area_struct *vma,
132 				    unsigned long address, pte_t *ptep)
133 {
134 }
135 
136 #endif /* !__ASSEMBLY__ */
137 
138 #define kern_addr_valid(addr)	(1)
139 
140 /* MMU-specific headers */
141 
142 #ifdef CONFIG_SUN3
143 #include <asm/sun3_pgtable.h>
144 #elif defined(CONFIG_COLDFIRE)
145 #include <asm/mcf_pgtable.h>
146 #else
147 #include <asm/motorola_pgtable.h>
148 #endif
149 
150 #ifndef __ASSEMBLY__
151 /*
152  * Macro to mark a page protection value as "uncacheable".
153  */
154 #ifdef CONFIG_COLDFIRE
155 # define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | CF_PAGE_NOCACHE))
156 #else
157 #ifdef SUN3_PAGE_NOCACHE
158 # define __SUN3_PAGE_NOCACHE	SUN3_PAGE_NOCACHE
159 #else
160 # define __SUN3_PAGE_NOCACHE	0
161 #endif
162 #define pgprot_noncached(prot)							\
163 	(MMU_IS_SUN3								\
164 	 ? (__pgprot(pgprot_val(prot) | __SUN3_PAGE_NOCACHE))			\
165 	 : ((MMU_IS_851 || MMU_IS_030)						\
166 	    ? (__pgprot(pgprot_val(prot) | _PAGE_NOCACHE030))			\
167 	    : (MMU_IS_040 || MMU_IS_060)					\
168 	    ? (__pgprot((pgprot_val(prot) & _CACHEMASK040) | _PAGE_NOCACHE_S))	\
169 	    : (prot)))
170 
171 #endif /* CONFIG_COLDFIRE */
172 #include <asm-generic/pgtable.h>
173 #endif /* !__ASSEMBLY__ */
174 
175 /*
176  * No page table caches to initialise
177  */
178 #define pgtable_cache_init()	do { } while (0)
179 
180 #define check_pgt_cache()	do { } while (0)
181 
182 #endif /* _M68K_PGTABLE_H */
183