xref: /openbmc/linux/arch/mips/mm/pgtable-64.c (revision 4f3db074)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1999, 2000 by Silicon Graphics
7  * Copyright (C) 2003 by Ralf Baechle
8  */
9 #include <linux/init.h>
10 #include <linux/mm.h>
11 #include <asm/fixmap.h>
12 #include <asm/pgtable.h>
13 #include <asm/pgalloc.h>
14 #include <asm/tlbflush.h>
15 
16 void pgd_init(unsigned long page)
17 {
18 	unsigned long *p, *end;
19 	unsigned long entry;
20 
21 #ifdef __PAGETABLE_PMD_FOLDED
22 	entry = (unsigned long)invalid_pte_table;
23 #else
24 	entry = (unsigned long)invalid_pmd_table;
25 #endif
26 
27 	p = (unsigned long *) page;
28 	end = p + PTRS_PER_PGD;
29 
30 	do {
31 		p[0] = entry;
32 		p[1] = entry;
33 		p[2] = entry;
34 		p[3] = entry;
35 		p[4] = entry;
36 		p += 8;
37 		p[-3] = entry;
38 		p[-2] = entry;
39 		p[-1] = entry;
40 	} while (p != end);
41 }
42 
43 #ifndef __PAGETABLE_PMD_FOLDED
44 void pmd_init(unsigned long addr, unsigned long pagetable)
45 {
46 	unsigned long *p, *end;
47 
48 	p = (unsigned long *) addr;
49 	end = p + PTRS_PER_PMD;
50 
51 	do {
52 		p[0] = pagetable;
53 		p[1] = pagetable;
54 		p[2] = pagetable;
55 		p[3] = pagetable;
56 		p[4] = pagetable;
57 		p += 8;
58 		p[-3] = pagetable;
59 		p[-2] = pagetable;
60 		p[-1] = pagetable;
61 	} while (p != end);
62 }
63 #endif
64 
65 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
66 
67 void pmdp_splitting_flush(struct vm_area_struct *vma,
68 			 unsigned long address,
69 			 pmd_t *pmdp)
70 {
71 	if (!pmd_trans_splitting(*pmdp)) {
72 		pmd_t pmd = pmd_mksplitting(*pmdp);
73 		set_pmd_at(vma->vm_mm, address, pmdp, pmd);
74 	}
75 }
76 
77 #endif
78 
79 pmd_t mk_pmd(struct page *page, pgprot_t prot)
80 {
81 	pmd_t pmd;
82 
83 	pmd_val(pmd) = (page_to_pfn(page) << _PFN_SHIFT) | pgprot_val(prot);
84 
85 	return pmd;
86 }
87 
88 void set_pmd_at(struct mm_struct *mm, unsigned long addr,
89 		pmd_t *pmdp, pmd_t pmd)
90 {
91 	*pmdp = pmd;
92 	flush_tlb_all();
93 }
94 
95 void __init pagetable_init(void)
96 {
97 	unsigned long vaddr;
98 	pgd_t *pgd_base;
99 
100 	/* Initialize the entire pgd.  */
101 	pgd_init((unsigned long)swapper_pg_dir);
102 #ifndef __PAGETABLE_PMD_FOLDED
103 	pmd_init((unsigned long)invalid_pmd_table, (unsigned long)invalid_pte_table);
104 #endif
105 	pgd_base = swapper_pg_dir;
106 	/*
107 	 * Fixed mappings:
108 	 */
109 	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
110 	fixrange_init(vaddr, vaddr + FIXADDR_SIZE, pgd_base);
111 }
112