xref: /openbmc/linux/arch/m68k/include/asm/pgtable_mm.h (revision ecfb9f40)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _M68K_PGTABLE_H
3 #define _M68K_PGTABLE_H
4 
5 
6 #if defined(CONFIG_SUN3) || defined(CONFIG_COLDFIRE)
7 #include <asm-generic/pgtable-nopmd.h>
8 #else
9 #include <asm-generic/pgtable-nopud.h>
10 #endif
11 
12 #include <asm/setup.h>
13 
14 #ifndef __ASSEMBLY__
15 #include <asm/processor.h>
16 #include <linux/sched.h>
17 #include <linux/threads.h>
18 
19 /*
20  * This file contains the functions and defines necessary to modify and use
21  * the m68k page table tree.
22  */
23 
24 #include <asm/virtconvert.h>
25 
26 /* Certain architectures need to do special things when pte's
27  * within a page table are directly modified.  Thus, the following
28  * hook is made available.
29  */
30 #define set_pte(pteptr, pteval)					\
31 	do{							\
32 		*(pteptr) = (pteval);				\
33 	} while(0)
34 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
35 
36 
37 /* PMD_SHIFT determines the size of the area a second-level page table can map */
38 #if CONFIG_PGTABLE_LEVELS == 3
39 #define PMD_SHIFT	18
40 #endif
41 #define PMD_SIZE	(1UL << PMD_SHIFT)
42 #define PMD_MASK	(~(PMD_SIZE-1))
43 
44 /* PGDIR_SHIFT determines what a third-level page table entry can map */
45 #ifdef CONFIG_SUN3
46 #define PGDIR_SHIFT     17
47 #elif defined(CONFIG_COLDFIRE)
48 #define PGDIR_SHIFT     22
49 #else
50 #define PGDIR_SHIFT	25
51 #endif
52 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
53 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
54 
55 /*
56  * entries per page directory level: the m68k is configured as three-level,
57  * so we do have PMD level physically.
58  */
59 #ifdef CONFIG_SUN3
60 #define PTRS_PER_PTE   16
61 #define __PAGETABLE_PMD_FOLDED 1
62 #define PTRS_PER_PMD   1
63 #define PTRS_PER_PGD   2048
64 #elif defined(CONFIG_COLDFIRE)
65 #define PTRS_PER_PTE	512
66 #define __PAGETABLE_PMD_FOLDED 1
67 #define PTRS_PER_PMD	1
68 #define PTRS_PER_PGD	1024
69 #else
70 #define PTRS_PER_PTE	64
71 #define PTRS_PER_PMD	128
72 #define PTRS_PER_PGD	128
73 #endif
74 #define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
75 
76 /* Virtual address region for use by kernel_map() */
77 #ifdef CONFIG_SUN3
78 #define KMAP_START	0x0dc00000
79 #define KMAP_END	0x0e000000
80 #elif defined(CONFIG_COLDFIRE)
81 #define KMAP_START	0xe0000000
82 #define KMAP_END	0xf0000000
83 #elif defined(CONFIG_VIRT)
84 #define	KMAP_START	0xdf000000
85 #define	KMAP_END	0xff000000
86 #else
87 #define	KMAP_START	0xd0000000
88 #define	KMAP_END	0xf0000000
89 #endif
90 
91 #ifdef CONFIG_SUN3
92 extern unsigned long m68k_vmalloc_end;
93 #define VMALLOC_START 0x0f800000
94 #define VMALLOC_END m68k_vmalloc_end
95 #elif defined(CONFIG_COLDFIRE)
96 #define VMALLOC_START	0xd0000000
97 #define VMALLOC_END	0xe0000000
98 #elif defined(CONFIG_VIRT)
99 #define VMALLOC_OFFSET	PAGE_SIZE
100 #define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
101 #define VMALLOC_END     KMAP_START
102 #else
103 /* Just any arbitrary offset to the start of the vmalloc VM area: the
104  * current 8MB value just means that there will be a 8MB "hole" after the
105  * physical memory until the kernel virtual memory starts.  That means that
106  * any out-of-bounds memory accesses will hopefully be caught.
107  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
108  * area for the same reason. ;)
109  */
110 #define VMALLOC_OFFSET	(8*1024*1024)
111 #define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
112 #define VMALLOC_END KMAP_START
113 #endif
114 
115 /* zero page used for uninitialized stuff */
116 extern void *empty_zero_page;
117 
118 /*
119  * ZERO_PAGE is a global shared page that is always zero: used
120  * for zero-mapped memory areas etc..
121  */
122 #define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
123 
124 /* number of bits that fit into a memory pointer */
125 #define BITS_PER_PTR			(8*sizeof(unsigned long))
126 
127 /* to align the pointer to a pointer address */
128 #define PTR_MASK			(~(sizeof(void*)-1))
129 
130 /* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */
131 /* 64-bit machines, beware!  SRB. */
132 #define SIZEOF_PTR_LOG2			       2
133 
134 extern void kernel_set_cachemode(void *addr, unsigned long size, int cmode);
135 
136 /*
137  * The m68k doesn't have any external MMU info: the kernel page
138  * tables contain all the necessary information.  The Sun3 does, but
139  * they are updated on demand.
140  */
141 static inline void update_mmu_cache(struct vm_area_struct *vma,
142 				    unsigned long address, pte_t *ptep)
143 {
144 }
145 
146 #endif /* !__ASSEMBLY__ */
147 
148 /* MMU-specific headers */
149 
150 #ifdef CONFIG_SUN3
151 #include <asm/sun3_pgtable.h>
152 #elif defined(CONFIG_COLDFIRE)
153 #include <asm/mcf_pgtable.h>
154 #else
155 #include <asm/motorola_pgtable.h>
156 #endif
157 
158 #ifndef __ASSEMBLY__
159 /*
160  * Macro to mark a page protection value as "uncacheable".
161  */
162 #ifdef CONFIG_COLDFIRE
163 # define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | CF_PAGE_NOCACHE))
164 #else
165 #ifdef SUN3_PAGE_NOCACHE
166 # define __SUN3_PAGE_NOCACHE	SUN3_PAGE_NOCACHE
167 #else
168 # define __SUN3_PAGE_NOCACHE	0
169 #endif
170 #define pgprot_noncached(prot)							\
171 	(MMU_IS_SUN3								\
172 	 ? (__pgprot(pgprot_val(prot) | __SUN3_PAGE_NOCACHE))			\
173 	 : ((MMU_IS_851 || MMU_IS_030)						\
174 	    ? (__pgprot(pgprot_val(prot) | _PAGE_NOCACHE030))			\
175 	    : (MMU_IS_040 || MMU_IS_060)					\
176 	    ? (__pgprot((pgprot_val(prot) & _CACHEMASK040) | _PAGE_NOCACHE_S))	\
177 	    : (prot)))
178 
179 pgprot_t pgprot_dmacoherent(pgprot_t prot);
180 #define pgprot_dmacoherent(prot)	pgprot_dmacoherent(prot)
181 
182 #endif /* CONFIG_COLDFIRE */
183 #endif /* !__ASSEMBLY__ */
184 
185 #endif /* _M68K_PGTABLE_H */
186