xref: /linux/arch/mips/mm/pgtable-32.c (revision e21f9e2e862e9eb3dd64eaddb6256b3e5098660f)
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/bootmem.h>
11 #include <linux/highmem.h>
12 #include <asm/fixmap.h>
13 #include <asm/pgtable.h>
14 #include <asm/pgalloc.h>
15 
16 void pgd_init(unsigned long page)
17 {
18 	unsigned long *p = (unsigned long *) page;
19 	int i;
20 
21 	for (i = 0; i < USER_PTRS_PER_PGD; i+=8) {
22 		p[i + 0] = (unsigned long) invalid_pte_table;
23 		p[i + 1] = (unsigned long) invalid_pte_table;
24 		p[i + 2] = (unsigned long) invalid_pte_table;
25 		p[i + 3] = (unsigned long) invalid_pte_table;
26 		p[i + 4] = (unsigned long) invalid_pte_table;
27 		p[i + 5] = (unsigned long) invalid_pte_table;
28 		p[i + 6] = (unsigned long) invalid_pte_table;
29 		p[i + 7] = (unsigned long) invalid_pte_table;
30 	}
31 }
32 
33 void __init pagetable_init(void)
34 {
35 	unsigned long vaddr;
36 	pgd_t *pgd_base;
37 #ifdef CONFIG_HIGHMEM
38 	pgd_t *pgd;
39 	pud_t *pud;
40 	pmd_t *pmd;
41 	pte_t *pte;
42 #endif
43 
44 	/* Initialize the entire pgd.  */
45 	pgd_init((unsigned long)swapper_pg_dir);
46 	pgd_init((unsigned long)swapper_pg_dir
47 		 + sizeof(pgd_t) * USER_PTRS_PER_PGD);
48 
49 	pgd_base = swapper_pg_dir;
50 
51 	/*
52 	 * Fixed mappings:
53 	 */
54 	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1);
55 	fixrange_init(vaddr & PMD_MASK, vaddr + FIXADDR_SIZE, pgd_base);
56 
57 #ifdef CONFIG_HIGHMEM
58 	/*
59 	 * Permanent kmaps:
60 	 */
61 	vaddr = PKMAP_BASE;
62 	fixrange_init(vaddr & PMD_MASK, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
63 
64 	pgd = swapper_pg_dir + __pgd_offset(vaddr);
65 	pud = pud_offset(pgd, vaddr);
66 	pmd = pmd_offset(pud, vaddr);
67 	pte = pte_offset_kernel(pmd, vaddr);
68 	pkmap_page_table = pte;
69 #endif
70 }
71