Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * arch/sh/mm/ioremap.c | |
3 | * | |
4 | * Re-map IO memory to kernel address space so that we can access it. | |
5 | * This is needed for high PCI addresses that aren't mapped in the | |
6 | * 640k-1MB IO memory area on PC's | |
7 | * | |
8 | * (C) Copyright 1995 1996 Linus Torvalds | |
b66c1a39 PM |
9 | * (C) Copyright 2005, 2006 Paul Mundt |
10 | * | |
11 | * This file is subject to the terms and conditions of the GNU General | |
12 | * Public License. See the file "COPYING" in the main directory of this | |
13 | * archive for more details. | |
1da177e4 | 14 | */ |
1da177e4 | 15 | #include <linux/vmalloc.h> |
b66c1a39 | 16 | #include <linux/module.h> |
1da177e4 | 17 | #include <linux/mm.h> |
a3e61d50 | 18 | #include <linux/pci.h> |
5b3e1a85 | 19 | #include <linux/io.h> |
1da177e4 LT |
20 | #include <asm/page.h> |
21 | #include <asm/pgalloc.h> | |
b66c1a39 | 22 | #include <asm/addrspace.h> |
1da177e4 LT |
23 | #include <asm/cacheflush.h> |
24 | #include <asm/tlbflush.h> | |
0fd14754 | 25 | #include <asm/mmu.h> |
1da177e4 | 26 | |
1da177e4 LT |
27 | /* |
28 | * Remap an arbitrary physical address space into the kernel virtual | |
29 | * address space. Needed when the kernel wants to access high addresses | |
30 | * directly. | |
31 | * | |
32 | * NOTE! We need to allow non-page-aligned mappings too: we will obviously | |
33 | * have to convert them into an offset in a page-aligned mapping, but the | |
34 | * caller shouldn't need to know that small detail. | |
35 | */ | |
bf3cdeda PM |
36 | void __iomem *__ioremap_caller(unsigned long phys_addr, unsigned long size, |
37 | unsigned long flags, void *caller) | |
1da177e4 | 38 | { |
bf3cdeda | 39 | struct vm_struct *area; |
b66c1a39 | 40 | unsigned long offset, last_addr, addr, orig_addr; |
5b3e1a85 | 41 | pgprot_t pgprot; |
1da177e4 LT |
42 | |
43 | /* Don't allow wraparound or zero size */ | |
44 | last_addr = phys_addr + size - 1; | |
45 | if (!size || last_addr < phys_addr) | |
46 | return NULL; | |
47 | ||
a3e61d50 | 48 | /* |
99f95f11 PM |
49 | * If we're in the fixed PCI memory range, mapping through page |
50 | * tables is not only pointless, but also fundamentally broken. | |
51 | * Just return the physical address instead. | |
a3e61d50 PM |
52 | * |
53 | * For boards that map a small PCI memory aperture somewhere in | |
54 | * P1/P2 space, ioremap() will already do the right thing, | |
55 | * and we'll never get this far. | |
56 | */ | |
99f95f11 | 57 | if (is_pci_memory_fixed_range(phys_addr, size)) |
a3e61d50 PM |
58 | return (void __iomem *)phys_addr; |
59 | ||
1da177e4 LT |
60 | /* |
61 | * Mappings have to be page-aligned | |
62 | */ | |
63 | offset = phys_addr & ~PAGE_MASK; | |
64 | phys_addr &= PAGE_MASK; | |
65 | size = PAGE_ALIGN(last_addr+1) - phys_addr; | |
66 | ||
67 | /* | |
68 | * Ok, go for it.. | |
69 | */ | |
bf3cdeda | 70 | area = get_vm_area_caller(size, VM_IOREMAP, caller); |
1da177e4 LT |
71 | if (!area) |
72 | return NULL; | |
73 | area->phys_addr = phys_addr; | |
b66c1a39 PM |
74 | orig_addr = addr = (unsigned long)area->addr; |
75 | ||
2f47f447 | 76 | #ifdef CONFIG_PMB |
b66c1a39 PM |
77 | /* |
78 | * First try to remap through the PMB once a valid VMA has been | |
79 | * established. Smaller allocations (or the rest of the size | |
80 | * remaining after a PMB mapping due to the size not being | |
81 | * perfectly aligned on a PMB size boundary) are then mapped | |
82 | * through the UTLB using conventional page tables. | |
83 | * | |
84 | * PMB entries are all pre-faulted. | |
85 | */ | |
2bea7ea7 | 86 | if (unlikely(phys_addr >= P1SEG)) { |
b66c1a39 PM |
87 | unsigned long mapped = pmb_remap(addr, phys_addr, size, flags); |
88 | ||
89 | if (likely(mapped)) { | |
90 | addr += mapped; | |
91 | phys_addr += mapped; | |
92 | size -= mapped; | |
93 | } | |
1da177e4 | 94 | } |
b66c1a39 PM |
95 | #endif |
96 | ||
5b3e1a85 | 97 | pgprot = __pgprot(pgprot_val(PAGE_KERNEL_NOCACHE) | flags); |
b66c1a39 | 98 | if (likely(size)) |
5b3e1a85 | 99 | if (ioremap_page_range(addr, addr + size, phys_addr, pgprot)) { |
b66c1a39 PM |
100 | vunmap((void *)orig_addr); |
101 | return NULL; | |
102 | } | |
103 | ||
104 | return (void __iomem *)(offset + (char *)orig_addr); | |
1da177e4 | 105 | } |
bf3cdeda | 106 | EXPORT_SYMBOL(__ioremap_caller); |
1da177e4 | 107 | |
78bf04fc PM |
108 | /* |
109 | * Simple checks for non-translatable mappings. | |
110 | */ | |
111 | static inline int iomapping_nontranslatable(unsigned long offset) | |
112 | { | |
113 | #ifdef CONFIG_29BIT | |
114 | /* | |
115 | * In 29-bit mode this includes the fixed P1/P2 areas, as well as | |
116 | * parts of P3. | |
117 | */ | |
118 | if (PXSEG(offset) < P3SEG || offset >= P3_ADDR_MAX) | |
119 | return 1; | |
120 | #endif | |
121 | ||
122 | if (is_pci_memory_fixed_range(offset, 0)) | |
123 | return 1; | |
124 | ||
125 | return 0; | |
126 | } | |
127 | ||
b66c1a39 | 128 | void __iounmap(void __iomem *addr) |
1da177e4 | 129 | { |
b66c1a39 PM |
130 | unsigned long vaddr = (unsigned long __force)addr; |
131 | struct vm_struct *p; | |
132 | ||
78bf04fc PM |
133 | /* |
134 | * Nothing to do if there is no translatable mapping. | |
135 | */ | |
136 | if (iomapping_nontranslatable(vaddr)) | |
b66c1a39 PM |
137 | return; |
138 | ||
2f47f447 | 139 | #ifdef CONFIG_PMB |
b66c1a39 PM |
140 | /* |
141 | * Purge any PMB entries that may have been established for this | |
142 | * mapping, then proceed with conventional VMA teardown. | |
143 | * | |
144 | * XXX: Note that due to the way that remove_vm_area() does | |
145 | * matching of the resultant VMA, we aren't able to fast-forward | |
146 | * the address past the PMB space until the end of the VMA where | |
147 | * the page tables reside. As such, unmap_vm_area() will be | |
148 | * forced to linearly scan over the area until it finds the page | |
149 | * tables where PTEs that need to be unmapped actually reside, | |
150 | * which is far from optimal. Perhaps we need to use a separate | |
151 | * VMA for the PMB mappings? | |
152 | * -- PFM. | |
153 | */ | |
154 | pmb_unmap(vaddr); | |
155 | #endif | |
156 | ||
157 | p = remove_vm_area((void *)(vaddr & PAGE_MASK)); | |
158 | if (!p) { | |
866e6b9e | 159 | printk(KERN_ERR "%s: bad address %p\n", __func__, addr); |
b66c1a39 PM |
160 | return; |
161 | } | |
162 | ||
163 | kfree(p); | |
1da177e4 | 164 | } |
b66c1a39 | 165 | EXPORT_SYMBOL(__iounmap); |