xref: /openbmc/linux/arch/mips/mm/pgtable-32.c (revision e15a5365)
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/pgalloc.h>
14 #include <asm/tlbflush.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 #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
34 pmd_t mk_pmd(struct page *page, pgprot_t prot)
35 {
36 	pmd_t pmd;
37 
38 	pmd_val(pmd) = (page_to_pfn(page) << _PFN_SHIFT) | pgprot_val(prot);
39 
40 	return pmd;
41 }
42 
43 
44 void set_pmd_at(struct mm_struct *mm, unsigned long addr,
45 		pmd_t *pmdp, pmd_t pmd)
46 {
47 	*pmdp = pmd;
48 	flush_tlb_all();
49 }
50 #endif /* defined(CONFIG_TRANSPARENT_HUGEPAGE) */
51 
52 void __init pagetable_init(void)
53 {
54 	unsigned long vaddr;
55 	pgd_t *pgd_base;
56 #ifdef CONFIG_HIGHMEM
57 	pgd_t *pgd;
58 	p4d_t *p4d;
59 	pud_t *pud;
60 	pmd_t *pmd;
61 	pte_t *pte;
62 #endif
63 
64 	/* Initialize the entire pgd.  */
65 	pgd_init((unsigned long)swapper_pg_dir);
66 	pgd_init((unsigned long)swapper_pg_dir
67 		 + sizeof(pgd_t) * USER_PTRS_PER_PGD);
68 
69 	pgd_base = swapper_pg_dir;
70 
71 	/*
72 	 * Fixed mappings:
73 	 */
74 	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1);
75 	fixrange_init(vaddr & PMD_MASK, vaddr + FIXADDR_SIZE, pgd_base);
76 
77 #ifdef CONFIG_HIGHMEM
78 	/*
79 	 * Permanent kmaps:
80 	 */
81 	vaddr = PKMAP_BASE;
82 	fixrange_init(vaddr & PMD_MASK, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
83 
84 	pgd = swapper_pg_dir + pgd_index(vaddr);
85 	p4d = p4d_offset(pgd, vaddr);
86 	pud = pud_offset(p4d, vaddr);
87 	pmd = pmd_offset(pud, vaddr);
88 	pte = pte_offset_kernel(pmd, vaddr);
89 	pkmap_page_table = pte;
90 #endif
91 }
92