diff options
Diffstat (limited to 'arch/m32r/mm/ioremap.c')
-rw-r--r-- | arch/m32r/mm/ioremap.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/arch/m32r/mm/ioremap.c b/arch/m32r/mm/ioremap.c new file mode 100644 index 000000000000..70c59055c19c --- /dev/null +++ b/arch/m32r/mm/ioremap.c | |||
@@ -0,0 +1,192 @@ | |||
1 | /* | ||
2 | * linux/arch/m32r/mm/ioremap.c | ||
3 | * | ||
4 | * Copyright (c) 2001, 2002 Hiroyuki Kondo | ||
5 | * | ||
6 | * Taken from mips version. | ||
7 | * (C) Copyright 1995 1996 Linus Torvalds | ||
8 | * (C) Copyright 2001 Ralf Baechle | ||
9 | */ | ||
10 | |||
11 | /* | ||
12 | * This file is subject to the terms and conditions of the GNU General Public | ||
13 | * License. See the file "COPYING" in the main directory of this archive | ||
14 | * for more details. | ||
15 | * | ||
16 | */ | ||
17 | |||
18 | #include <linux/module.h> | ||
19 | #include <asm/addrspace.h> | ||
20 | #include <asm/byteorder.h> | ||
21 | |||
22 | #include <linux/vmalloc.h> | ||
23 | #include <asm/io.h> | ||
24 | #include <asm/pgalloc.h> | ||
25 | #include <asm/cacheflush.h> | ||
26 | #include <asm/tlbflush.h> | ||
27 | |||
28 | static inline void | ||
29 | remap_area_pte(pte_t * pte, unsigned long address, unsigned long size, | ||
30 | unsigned long phys_addr, unsigned long flags) | ||
31 | { | ||
32 | unsigned long end; | ||
33 | unsigned long pfn; | ||
34 | pgprot_t pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_READ | ||
35 | | _PAGE_WRITE | flags); | ||
36 | |||
37 | address &= ~PMD_MASK; | ||
38 | end = address + size; | ||
39 | if (end > PMD_SIZE) | ||
40 | end = PMD_SIZE; | ||
41 | if (address >= end) | ||
42 | BUG(); | ||
43 | pfn = phys_addr >> PAGE_SHIFT; | ||
44 | do { | ||
45 | if (!pte_none(*pte)) { | ||
46 | printk("remap_area_pte: page already exists\n"); | ||
47 | BUG(); | ||
48 | } | ||
49 | set_pte(pte, pfn_pte(pfn, pgprot)); | ||
50 | address += PAGE_SIZE; | ||
51 | pfn++; | ||
52 | pte++; | ||
53 | } while (address && (address < end)); | ||
54 | } | ||
55 | |||
56 | static inline int | ||
57 | remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size, | ||
58 | unsigned long phys_addr, unsigned long flags) | ||
59 | { | ||
60 | unsigned long end; | ||
61 | |||
62 | address &= ~PGDIR_MASK; | ||
63 | end = address + size; | ||
64 | if (end > PGDIR_SIZE) | ||
65 | end = PGDIR_SIZE; | ||
66 | phys_addr -= address; | ||
67 | if (address >= end) | ||
68 | BUG(); | ||
69 | do { | ||
70 | pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address); | ||
71 | if (!pte) | ||
72 | return -ENOMEM; | ||
73 | remap_area_pte(pte, address, end - address, address + phys_addr, flags); | ||
74 | address = (address + PMD_SIZE) & PMD_MASK; | ||
75 | pmd++; | ||
76 | } while (address && (address < end)); | ||
77 | return 0; | ||
78 | } | ||
79 | |||
80 | static int | ||
81 | remap_area_pages(unsigned long address, unsigned long phys_addr, | ||
82 | unsigned long size, unsigned long flags) | ||
83 | { | ||
84 | int error; | ||
85 | pgd_t * dir; | ||
86 | unsigned long end = address + size; | ||
87 | |||
88 | phys_addr -= address; | ||
89 | dir = pgd_offset(&init_mm, address); | ||
90 | flush_cache_all(); | ||
91 | if (address >= end) | ||
92 | BUG(); | ||
93 | spin_lock(&init_mm.page_table_lock); | ||
94 | do { | ||
95 | pmd_t *pmd; | ||
96 | pmd = pmd_alloc(&init_mm, dir, address); | ||
97 | error = -ENOMEM; | ||
98 | if (!pmd) | ||
99 | break; | ||
100 | if (remap_area_pmd(pmd, address, end - address, | ||
101 | phys_addr + address, flags)) | ||
102 | break; | ||
103 | error = 0; | ||
104 | address = (address + PGDIR_SIZE) & PGDIR_MASK; | ||
105 | dir++; | ||
106 | } while (address && (address < end)); | ||
107 | spin_unlock(&init_mm.page_table_lock); | ||
108 | flush_tlb_all(); | ||
109 | return error; | ||
110 | } | ||
111 | |||
112 | /* | ||
113 | * Generic mapping function (not visible outside): | ||
114 | */ | ||
115 | |||
116 | /* | ||
117 | * Remap an arbitrary physical address space into the kernel virtual | ||
118 | * address space. Needed when the kernel wants to access high addresses | ||
119 | * directly. | ||
120 | * | ||
121 | * NOTE! We need to allow non-page-aligned mappings too: we will obviously | ||
122 | * have to convert them into an offset in a page-aligned mapping, but the | ||
123 | * caller shouldn't need to know that small detail. | ||
124 | */ | ||
125 | |||
126 | #define IS_LOW512(addr) (!((unsigned long)(addr) & ~0x1fffffffUL)) | ||
127 | |||
128 | void __iomem * | ||
129 | __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags) | ||
130 | { | ||
131 | void __iomem * addr; | ||
132 | struct vm_struct * area; | ||
133 | unsigned long offset, last_addr; | ||
134 | |||
135 | /* Don't allow wraparound or zero size */ | ||
136 | last_addr = phys_addr + size - 1; | ||
137 | if (!size || last_addr < phys_addr) | ||
138 | return NULL; | ||
139 | |||
140 | /* | ||
141 | * Map objects in the low 512mb of address space using KSEG1, otherwise | ||
142 | * map using page tables. | ||
143 | */ | ||
144 | if (IS_LOW512(phys_addr) && IS_LOW512(phys_addr + size - 1)) | ||
145 | return (void *) KSEG1ADDR(phys_addr); | ||
146 | |||
147 | /* | ||
148 | * Don't allow anybody to remap normal RAM that we're using.. | ||
149 | */ | ||
150 | if (phys_addr < virt_to_phys(high_memory)) { | ||
151 | char *t_addr, *t_end; | ||
152 | struct page *page; | ||
153 | |||
154 | t_addr = __va(phys_addr); | ||
155 | t_end = t_addr + (size - 1); | ||
156 | |||
157 | for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++) | ||
158 | if(!PageReserved(page)) | ||
159 | return NULL; | ||
160 | } | ||
161 | |||
162 | /* | ||
163 | * Mappings have to be page-aligned | ||
164 | */ | ||
165 | offset = phys_addr & ~PAGE_MASK; | ||
166 | phys_addr &= PAGE_MASK; | ||
167 | size = PAGE_ALIGN(last_addr + 1) - phys_addr; | ||
168 | |||
169 | /* | ||
170 | * Ok, go for it.. | ||
171 | */ | ||
172 | area = get_vm_area(size, VM_IOREMAP); | ||
173 | if (!area) | ||
174 | return NULL; | ||
175 | area->phys_addr = phys_addr; | ||
176 | addr = (void __iomem *) area->addr; | ||
177 | if (remap_area_pages((unsigned long)addr, phys_addr, size, flags)) { | ||
178 | vunmap((void __force *) addr); | ||
179 | return NULL; | ||
180 | } | ||
181 | |||
182 | return (void __iomem *) (offset + (char __iomem *)addr); | ||
183 | } | ||
184 | |||
185 | #define IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == KSEG1) | ||
186 | |||
187 | void iounmap(volatile void __iomem *addr) | ||
188 | { | ||
189 | if (!IS_KSEG1(addr)) | ||
190 | vfree((void *) (PAGE_MASK & (unsigned long) addr)); | ||
191 | } | ||
192 | |||