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
167
168
169
170
|
/*
* arch/cris/mm/ioremap.c
*
* Re-map IO memory to kernel address space so that we can access it.
* Needed for memory-mapped I/O devices mapped outside our normal DRAM
* window (that is, all memory-mapped I/O devices).
*
* (C) Copyright 1995 1996 Linus Torvalds
* CRIS-port by Axis Communications AB
*/
#include <linux/vmalloc.h>
#include <asm/io.h>
#include <asm/pgalloc.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/arch/memmap.h>
static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
unsigned long phys_addr, pgprot_t prot)
{
unsigned long end;
address &= ~PMD_MASK;
end = address + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
if (address >= end)
BUG();
do {
if (!pte_none(*pte)) {
printk("remap_area_pte: page already exists\n");
BUG();
}
set_pte(pte, mk_pte_phys(phys_addr, prot));
address += PAGE_SIZE;
phys_addr += PAGE_SIZE;
pte++;
} while (address && (address < end));
}
static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
unsigned long phys_addr, pgprot_t prot)
{
unsigned long end;
address &= ~PGDIR_MASK;
end = address + size;
if (end > PGDIR_SIZE)
end = PGDIR_SIZE;
phys_addr -= address;
if (address >= end)
BUG();
do {
pte_t * pte = pte_alloc_kernel(pmd, address);
if (!pte)
return -ENOMEM;
remap_area_pte(pte, address, end - address, address + phys_addr, prot);
address = (address + PMD_SIZE) & PMD_MASK;
pmd++;
} while (address && (address < end));
return 0;
}
static int remap_area_pages(unsigned long address, unsigned long phys_addr,
unsigned long size, pgprot_t prot)
{
int error;
pgd_t * dir;
unsigned long end = address + size;
phys_addr -= address;
dir = pgd_offset(&init_mm, address);
flush_cache_all();
if (address >= end)
BUG();
do {
pud_t *pud;
pmd_t *pmd;
error = -ENOMEM;
pud = pud_alloc(&init_mm, dir, address);
if (!pud)
break;
pmd = pmd_alloc(&init_mm, pud, address);
if (!pmd)
break;
if (remap_area_pmd(pmd, address, end - address,
phys_addr + address, prot))
break;
error = 0;
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
flush_tlb_all();
return error;
}
/*
* Generic mapping function (not visible outside):
*/
/*
* Remap an arbitrary physical address space into the kernel virtual
* address space. Needed when the kernel wants to access high addresses
* directly.
*
* NOTE! We need to allow non-page-aligned mappings too: we will obviously
* have to convert them into an offset in a page-aligned mapping, but the
* caller shouldn't need to know that small detail.
*/
void __iomem * __ioremap_prot(unsigned long phys_addr, unsigned long size, pgprot_t prot)
{
void __iomem * addr;
struct vm_struct * area;
unsigned long offset, last_addr;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
return NULL;
/*
* Mappings have to be page-aligned
*/
offset = phys_addr & ~PAGE_MASK;
phys_addr &= PAGE_MASK;
size = PAGE_ALIGN(last_addr+1) - phys_addr;
/*
* Ok, go for it..
*/
area = get_vm_area(size, VM_IOREMAP);
if (!area)
return NULL;
addr = (void __iomem *)area->addr;
if (remap_area_pages((unsigned long) addr, phys_addr, size, prot)) {
vfree((void __force *)addr);
return NULL;
}
return (void __iomem *) (offset + (char __iomem *)addr);
}
void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
{
return __ioremap_prot(phys_addr, size,
__pgprot(_PAGE_PRESENT | __READABLE |
__WRITEABLE | _PAGE_GLOBAL |
_PAGE_KERNEL | flags));
}
/**
* ioremap_nocache - map bus memory into CPU space
* @offset: bus address of the memory
* @size: size of the resource to map
*
* Must be freed with iounmap.
*/
void __iomem *ioremap_nocache (unsigned long phys_addr, unsigned long size)
{
return __ioremap(phys_addr | MEM_NON_CACHEABLE, size, 0);
}
void iounmap(volatile void __iomem *addr)
{
if (addr > high_memory)
return vfree((void *) (PAGE_MASK & (unsigned long) addr));
}
|
