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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 * (C) Copyright 1995 1996 Linus Torvalds
7 * (C) Copyright 2001, 2002 Ralf Baechle
8 */
9#include <linux/export.h>
10#include <asm/addrspace.h>
11#include <asm/byteorder.h>
12#include <linux/sched.h>
13#include <linux/slab.h>
14#include <linux/vmalloc.h>
15#include <linux/mm_types.h>
16#include <asm/cacheflush.h>
17#include <asm/io.h>
18#include <asm/tlbflush.h>
19
20static inline void remap_area_pte(pte_t * pte, unsigned long address,
21 phys_addr_t size, phys_addr_t phys_addr, unsigned long flags)
22{
23 phys_addr_t end;
24 unsigned long pfn;
25 pgprot_t pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | __READABLE
26 | __WRITEABLE | flags);
27
28 address &= ~PMD_MASK;
29 end = address + size;
30 if (end > PMD_SIZE)
31 end = PMD_SIZE;
32 BUG_ON(address >= end);
33 pfn = phys_addr >> PAGE_SHIFT;
34 do {
35 if (!pte_none(*pte)) {
36 printk("remap_area_pte: page already exists\n");
37 BUG();
38 }
39 set_pte(pte, pfn_pte(pfn, pgprot));
40 address += PAGE_SIZE;
41 pfn++;
42 pte++;
43 } while (address && (address < end));
44}
45
46static inline int remap_area_pmd(pmd_t * pmd, unsigned long address,
47 phys_addr_t size, phys_addr_t phys_addr, unsigned long flags)
48{
49 phys_addr_t end;
50
51 address &= ~PGDIR_MASK;
52 end = address + size;
53 if (end > PGDIR_SIZE)
54 end = PGDIR_SIZE;
55 phys_addr -= address;
56 BUG_ON(address >= end);
57 do {
58 pte_t * pte = pte_alloc_kernel(pmd, address);
59 if (!pte)
60 return -ENOMEM;
61 remap_area_pte(pte, address, end - address, address + phys_addr, flags);
62 address = (address + PMD_SIZE) & PMD_MASK;
63 pmd++;
64 } while (address && (address < end));
65 return 0;
66}
67
68static int remap_area_pages(unsigned long address, phys_addr_t phys_addr,
69 phys_addr_t size, unsigned long flags)
70{
71 int error;
72 pgd_t * dir;
73 unsigned long end = address + size;
74
75 phys_addr -= address;
76 dir = pgd_offset(&init_mm, address);
77 flush_cache_all();
78 BUG_ON(address >= end);
79 do {
80 pud_t *pud;
81 pmd_t *pmd;
82
83 error = -ENOMEM;
84 pud = pud_alloc(&init_mm, dir, address);
85 if (!pud)
86 break;
87 pmd = pmd_alloc(&init_mm, pud, address);
88 if (!pmd)
89 break;
90 if (remap_area_pmd(pmd, address, end - address,
91 phys_addr + address, flags))
92 break;
93 error = 0;
94 address = (address + PGDIR_SIZE) & PGDIR_MASK;
95 dir++;
96 } while (address && (address < end));
97 flush_tlb_all();
98 return error;
99}
100
101/*
102 * Generic mapping function (not visible outside):
103 */
104
105/*
106 * Remap an arbitrary physical address space into the kernel virtual
107 * address space. Needed when the kernel wants to access high addresses
108 * directly.
109 *
110 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
111 * have to convert them into an offset in a page-aligned mapping, but the
112 * caller shouldn't need to know that small detail.
113 */
114
115#define IS_LOW512(addr) (!((phys_addr_t)(addr) & (phys_addr_t) ~0x1fffffffULL))
116
117void __iomem * __ioremap(phys_addr_t phys_addr, phys_addr_t size, unsigned long flags)
118{
119 struct vm_struct * area;
120 unsigned long offset;
121 phys_addr_t last_addr;
122 void * addr;
123
124 phys_addr = fixup_bigphys_addr(phys_addr, size);
125
126 /* Don't allow wraparound or zero size */
127 last_addr = phys_addr + size - 1;
128 if (!size || last_addr < phys_addr)
129 return NULL;
130
131 /*
132 * Map uncached objects in the low 512mb of address space using KSEG1,
133 * otherwise map using page tables.
134 */
135 if (IS_LOW512(phys_addr) && IS_LOW512(last_addr) &&
136 flags == _CACHE_UNCACHED)
137 return (void __iomem *) CKSEG1ADDR(phys_addr);
138
139 /*
140 * Don't allow anybody to remap normal RAM that we're using..
141 */
142 if (phys_addr < virt_to_phys(high_memory)) {
143 char *t_addr, *t_end;
144 struct page *page;
145
146 t_addr = __va(phys_addr);
147 t_end = t_addr + (size - 1);
148
149 for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++)
150 if(!PageReserved(page))
151 return NULL;
152 }
153
154 /*
155 * Mappings have to be page-aligned
156 */
157 offset = phys_addr & ~PAGE_MASK;
158 phys_addr &= PAGE_MASK;
159 size = PAGE_ALIGN(last_addr + 1) - phys_addr;
160
161 /*
162 * Ok, go for it..
163 */
164 area = get_vm_area(size, VM_IOREMAP);
165 if (!area)
166 return NULL;
167 addr = area->addr;
168 if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
169 vunmap(addr);
170 return NULL;
171 }
172
173 return (void __iomem *) (offset + (char *)addr);
174}
175
176#define IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1)
177
178void __iounmap(const volatile void __iomem *addr)
179{
180 struct vm_struct *p;
181
182 if (IS_KSEG1(addr))
183 return;
184
185 p = remove_vm_area((void *) (PAGE_MASK & (unsigned long __force) addr));
186 if (!p)
187 printk(KERN_ERR "iounmap: bad address %p\n", addr);
188
189 kfree(p);
190}
191
192EXPORT_SYMBOL(__ioremap);
193EXPORT_SYMBOL(__iounmap);
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 * (C) Copyright 1995 1996 Linus Torvalds
7 * (C) Copyright 2001, 2002 Ralf Baechle
8 */
9#include <linux/module.h>
10#include <asm/addrspace.h>
11#include <asm/byteorder.h>
12#include <linux/sched.h>
13#include <linux/slab.h>
14#include <linux/vmalloc.h>
15#include <asm/cacheflush.h>
16#include <asm/io.h>
17#include <asm/tlbflush.h>
18
19static inline void remap_area_pte(pte_t * pte, unsigned long address,
20 phys_addr_t size, phys_addr_t phys_addr, unsigned long flags)
21{
22 phys_addr_t end;
23 unsigned long pfn;
24 pgprot_t pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | __READABLE
25 | __WRITEABLE | flags);
26
27 address &= ~PMD_MASK;
28 end = address + size;
29 if (end > PMD_SIZE)
30 end = PMD_SIZE;
31 BUG_ON(address >= end);
32 pfn = phys_addr >> PAGE_SHIFT;
33 do {
34 if (!pte_none(*pte)) {
35 printk("remap_area_pte: page already exists\n");
36 BUG();
37 }
38 set_pte(pte, pfn_pte(pfn, pgprot));
39 address += PAGE_SIZE;
40 pfn++;
41 pte++;
42 } while (address && (address < end));
43}
44
45static inline int remap_area_pmd(pmd_t * pmd, unsigned long address,
46 phys_addr_t size, phys_addr_t phys_addr, unsigned long flags)
47{
48 phys_addr_t end;
49
50 address &= ~PGDIR_MASK;
51 end = address + size;
52 if (end > PGDIR_SIZE)
53 end = PGDIR_SIZE;
54 phys_addr -= address;
55 BUG_ON(address >= end);
56 do {
57 pte_t * pte = pte_alloc_kernel(pmd, address);
58 if (!pte)
59 return -ENOMEM;
60 remap_area_pte(pte, address, end - address, address + phys_addr, flags);
61 address = (address + PMD_SIZE) & PMD_MASK;
62 pmd++;
63 } while (address && (address < end));
64 return 0;
65}
66
67static int remap_area_pages(unsigned long address, phys_addr_t phys_addr,
68 phys_addr_t size, unsigned long flags)
69{
70 int error;
71 pgd_t * dir;
72 unsigned long end = address + size;
73
74 phys_addr -= address;
75 dir = pgd_offset(&init_mm, address);
76 flush_cache_all();
77 BUG_ON(address >= end);
78 do {
79 pud_t *pud;
80 pmd_t *pmd;
81
82 error = -ENOMEM;
83 pud = pud_alloc(&init_mm, dir, address);
84 if (!pud)
85 break;
86 pmd = pmd_alloc(&init_mm, pud, address);
87 if (!pmd)
88 break;
89 if (remap_area_pmd(pmd, address, end - address,
90 phys_addr + address, flags))
91 break;
92 error = 0;
93 address = (address + PGDIR_SIZE) & PGDIR_MASK;
94 dir++;
95 } while (address && (address < end));
96 flush_tlb_all();
97 return error;
98}
99
100/*
101 * Generic mapping function (not visible outside):
102 */
103
104/*
105 * Remap an arbitrary physical address space into the kernel virtual
106 * address space. Needed when the kernel wants to access high addresses
107 * directly.
108 *
109 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
110 * have to convert them into an offset in a page-aligned mapping, but the
111 * caller shouldn't need to know that small detail.
112 */
113
114#define IS_LOW512(addr) (!((phys_addr_t)(addr) & (phys_addr_t) ~0x1fffffffULL))
115
116void __iomem * __ioremap(phys_addr_t phys_addr, phys_addr_t size, unsigned long flags)
117{
118 struct vm_struct * area;
119 unsigned long offset;
120 phys_addr_t last_addr;
121 void * addr;
122
123 phys_addr = fixup_bigphys_addr(phys_addr, size);
124
125 /* Don't allow wraparound or zero size */
126 last_addr = phys_addr + size - 1;
127 if (!size || last_addr < phys_addr)
128 return NULL;
129
130 /*
131 * Map uncached objects in the low 512mb of address space using KSEG1,
132 * otherwise map using page tables.
133 */
134 if (IS_LOW512(phys_addr) && IS_LOW512(last_addr) &&
135 flags == _CACHE_UNCACHED)
136 return (void __iomem *) CKSEG1ADDR(phys_addr);
137
138 /*
139 * Don't allow anybody to remap normal RAM that we're using..
140 */
141 if (phys_addr < virt_to_phys(high_memory)) {
142 char *t_addr, *t_end;
143 struct page *page;
144
145 t_addr = __va(phys_addr);
146 t_end = t_addr + (size - 1);
147
148 for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++)
149 if(!PageReserved(page))
150 return NULL;
151 }
152
153 /*
154 * Mappings have to be page-aligned
155 */
156 offset = phys_addr & ~PAGE_MASK;
157 phys_addr &= PAGE_MASK;
158 size = PAGE_ALIGN(last_addr + 1) - phys_addr;
159
160 /*
161 * Ok, go for it..
162 */
163 area = get_vm_area(size, VM_IOREMAP);
164 if (!area)
165 return NULL;
166 addr = area->addr;
167 if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
168 vunmap(addr);
169 return NULL;
170 }
171
172 return (void __iomem *) (offset + (char *)addr);
173}
174
175#define IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1)
176
177void __iounmap(const volatile void __iomem *addr)
178{
179 struct vm_struct *p;
180
181 if (IS_KSEG1(addr))
182 return;
183
184 p = remove_vm_area((void *) (PAGE_MASK & (unsigned long __force) addr));
185 if (!p)
186 printk(KERN_ERR "iounmap: bad address %p\n", addr);
187
188 kfree(p);
189}
190
191EXPORT_SYMBOL(__ioremap);
192EXPORT_SYMBOL(__iounmap);