aboutsummaryrefslogtreecommitdiffstats
path: root/arch/sparc64/mm/generic.c
blob: 580b63da836bcee565fb435b6f833ac6f1eb9b70 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
/* $Id: generic.c,v 1.18 2001/12/21 04:56:15 davem Exp $
 * generic.c: Generic Sparc mm routines that are not dependent upon
 *            MMU type but are Sparc specific.
 *
 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/pagemap.h>

#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/tlbflush.h>

static inline pte_t mk_pte_io(unsigned long page, pgprot_t prot, int space)
{
	pte_t pte;
	pte_val(pte) = (((page) | pgprot_val(prot) | _PAGE_E) &
			~(unsigned long)_PAGE_CACHE);
	pte_val(pte) |= (((unsigned long)space) << 32);
	return pte;
}

/* Remap IO memory, the same way as remap_pfn_range(), but use
 * the obio memory space.
 *
 * They use a pgprot that sets PAGE_IO and does not check the
 * mem_map table as this is independent of normal memory.
 */
static inline void io_remap_pte_range(struct mm_struct *mm, pte_t * pte,
				      unsigned long address,
				      unsigned long size,
				      unsigned long offset, pgprot_t prot,
				      int space)
{
	unsigned long end;

	/* clear hack bit that was used as a write_combine side-effect flag */
	offset &= ~0x1UL;
	address &= ~PMD_MASK;
	end = address + size;
	if (end > PMD_SIZE)
		end = PMD_SIZE;
	do {
		pte_t entry;
		unsigned long curend = address + PAGE_SIZE;
		
		entry = mk_pte_io(offset, prot, space);
		if (!(address & 0xffff)) {
			if (!(address & 0x3fffff) && !(offset & 0x3ffffe) && end >= address + 0x400000) {
				entry = mk_pte_io(offset,
						  __pgprot(pgprot_val (prot) | _PAGE_SZ4MB),
						  space);
				curend = address + 0x400000;
				offset += 0x400000;
			} else if (!(address & 0x7ffff) && !(offset & 0x7fffe) && end >= address + 0x80000) {
				entry = mk_pte_io(offset,
						  __pgprot(pgprot_val (prot) | _PAGE_SZ512K),
						  space);
				curend = address + 0x80000;
				offset += 0x80000;
			} else if (!(offset & 0xfffe) && end >= address + 0x10000) {
				entry = mk_pte_io(offset,
						  __pgprot(pgprot_val (prot) | _PAGE_SZ64K),
						  space);
				curend = address + 0x10000;
				offset += 0x10000;
			} else
				offset += PAGE_SIZE;
		} else
			offset += PAGE_SIZE;

		do {
			BUG_ON(!pte_none(*pte));
			set_pte_at(mm, address, pte, entry);
			address += PAGE_SIZE;
			pte_val(entry) += PAGE_SIZE;
			pte++;
		} while (address < curend);
	} while (address < end);
}

static inline int io_remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned long address, unsigned long size,
	unsigned long offset, pgprot_t prot, int space)
{
	unsigned long end;

	address &= ~PGDIR_MASK;
	end = address + size;
	if (end > PGDIR_SIZE)
		end = PGDIR_SIZE;
	offset -= address;
	do {
		pte_t * pte = pte_alloc_map(mm, pmd, address);
		if (!pte)
			return -ENOMEM;
		io_remap_pte_range(mm, pte, address, end - address, address + offset, prot, space);
		pte_unmap(pte);
		address = (address + PMD_SIZE) & PMD_MASK;
		pmd++;
	} while (address < end);
	return 0;
}

static inline int io_remap_pud_range(struct mm_struct *mm, pud_t * pud, unsigned long address, unsigned long size,
	unsigned long offset, pgprot_t prot, int space)
{
	unsigned long end;

	address &= ~PUD_MASK;
	end = address + size;
	if (end > PUD_SIZE)
		end = PUD_SIZE;
	offset -= address;
	do {
		pmd_t *pmd = pmd_alloc(mm, pud, address);
		if (!pud)
			return -ENOMEM;
		io_remap_pmd_range(mm, pmd, address, end - address, address + offset, prot, space);
		address = (address + PUD_SIZE) & PUD_MASK;
		pud++;
	} while (address < end);
	return 0;
}

int io_remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
		unsigned long pfn, unsigned long size, pgprot_t prot)
{
	int error = 0;
	pgd_t * dir;
	unsigned long beg = from;
	unsigned long end = from + size;
	struct mm_struct *mm = vma->vm_mm;
	int space = GET_IOSPACE(pfn);
	unsigned long offset = GET_PFN(pfn) << PAGE_SHIFT;
	unsigned long phys_base;

	phys_base = offset | (((unsigned long) space) << 32UL);

	/* See comment in mm/memory.c remap_pfn_range */
	vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
	vma->vm_pgoff = phys_base >> PAGE_SHIFT;

	prot = __pgprot(pg_iobits);
	offset -= from;
	dir = pgd_offset(mm, from);
	flush_cache_range(vma, beg, end);

	while (from < end) {
		pud_t *pud = pud_alloc(mm, dir, from);
		error = -ENOMEM;
		if (!pud)
			break;
		error = io_remap_pud_range(mm, pud, from, end - from, offset + from, prot, space);
		if (error)
			break;
		from = (from + PGDIR_SIZE) & PGDIR_MASK;
		dir++;
	}

	flush_tlb_range(vma, beg, end);
	return error;
}