xref: /openbmc/linux/arch/mips/mm/pgtable-32.c (revision 4eb7ae7a)
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) 2003 by Ralf Baechle
7  */
8 #include <linux/init.h>
9 #include <linux/mm.h>
10 #include <linux/memblock.h>
11 #include <linux/highmem.h>
12 #include <asm/fixmap.h>
13 #include <asm/pgtable.h>
14 #include <asm/pgalloc.h>
15 #include <asm/tlbflush.h>
16 
17 void pgd_init(unsigned long page)
18 {
19 	unsigned long *p = (unsigned long *) page;
20 	int i;
21 
22 	for (i = 0; i < USER_PTRS_PER_PGD; i+=8) {
23 		p[i + 0] = (unsigned long) invalid_pte_table;
24 		p[i + 1] = (unsigned long) invalid_pte_table;
25 		p[i + 2] = (unsigned long) invalid_pte_table;
26 		p[i + 3] = (unsigned long) invalid_pte_table;
27 		p[i + 4] = (unsigned long) invalid_pte_table;
28 		p[i + 5] = (unsigned long) invalid_pte_table;
29 		p[i + 6] = (unsigned long) invalid_pte_table;
30 		p[i + 7] = (unsigned long) invalid_pte_table;
31 	}
32 }
33 
34 #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
35 pmd_t mk_pmd(struct page *page, pgprot_t prot)
36 {
37 	pmd_t pmd;
38 
39 	pmd_val(pmd) = (page_to_pfn(page) << _PFN_SHIFT) | pgprot_val(prot);
40 
41 	return pmd;
42 }
43 
44 
45 void set_pmd_at(struct mm_struct *mm, unsigned long addr,
46 		pmd_t *pmdp, pmd_t pmd)
47 {
48 	*pmdp = pmd;
49 	flush_tlb_all();
50 }
51 #endif /* defined(CONFIG_TRANSPARENT_HUGEPAGE) */
52 
53 void __init pagetable_init(void)
54 {
55 	unsigned long vaddr;
56 	pgd_t *pgd_base;
57 #ifdef CONFIG_HIGHMEM
58 	pgd_t *pgd;
59 	p4d_t *p4d;
60 	pud_t *pud;
61 	pmd_t *pmd;
62 	pte_t *pte;
63 #endif
64 
65 	/* Initialize the entire pgd.  */
66 	pgd_init((unsigned long)swapper_pg_dir);
67 	pgd_init((unsigned long)swapper_pg_dir
68 		 + sizeof(pgd_t) * USER_PTRS_PER_PGD);
69 
70 	pgd_base = swapper_pg_dir;
71 
72 	/*
73 	 * Fixed mappings:
74 	 */
75 	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1);
76 	fixrange_init(vaddr & PMD_MASK, vaddr + FIXADDR_SIZE, pgd_base);
77 
78 #ifdef CONFIG_HIGHMEM
79 	/*
80 	 * Permanent kmaps:
81 	 */
82 	vaddr = PKMAP_BASE;
83 	fixrange_init(vaddr & PMD_MASK, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
84 
85 	pgd = swapper_pg_dir + pgd_index(vaddr);
86 	p4d = p4d_offset(pgd, vaddr);
87 	pud = pud_offset(p4d, vaddr);
88 	pmd = pmd_offset(pud, vaddr);
89 	pte = pte_offset_kernel(pmd, vaddr);
90 	pkmap_page_table = pte;
91 #endif
92 }
93