diff options
Diffstat (limited to 'arch/sh/mm/ioremap_fixed.c')
-rw-r--r-- | arch/sh/mm/ioremap_fixed.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/arch/sh/mm/ioremap_fixed.c b/arch/sh/mm/ioremap_fixed.c new file mode 100644 index 000000000000..0b78b1e20ef1 --- /dev/null +++ b/arch/sh/mm/ioremap_fixed.c | |||
@@ -0,0 +1,128 @@ | |||
1 | /* | ||
2 | * Re-map IO memory to kernel address space so that we can access it. | ||
3 | * | ||
4 | * These functions should only be used when it is necessary to map a | ||
5 | * physical address space into the kernel address space before ioremap() | ||
6 | * can be used, e.g. early in boot before paging_init(). | ||
7 | * | ||
8 | * Copyright (C) 2009 Matt Fleming | ||
9 | */ | ||
10 | |||
11 | #include <linux/vmalloc.h> | ||
12 | #include <linux/ioport.h> | ||
13 | #include <linux/module.h> | ||
14 | #include <linux/mm.h> | ||
15 | #include <linux/io.h> | ||
16 | #include <linux/bootmem.h> | ||
17 | #include <linux/proc_fs.h> | ||
18 | #include <linux/slab.h> | ||
19 | #include <asm/fixmap.h> | ||
20 | #include <asm/page.h> | ||
21 | #include <asm/pgalloc.h> | ||
22 | #include <asm/addrspace.h> | ||
23 | #include <asm/cacheflush.h> | ||
24 | #include <asm/tlbflush.h> | ||
25 | #include <asm/mmu.h> | ||
26 | #include <asm/mmu_context.h> | ||
27 | |||
28 | struct ioremap_map { | ||
29 | void __iomem *addr; | ||
30 | unsigned long size; | ||
31 | unsigned long fixmap_addr; | ||
32 | }; | ||
33 | |||
34 | static struct ioremap_map ioremap_maps[FIX_N_IOREMAPS]; | ||
35 | |||
36 | void __init ioremap_fixed_init(void) | ||
37 | { | ||
38 | struct ioremap_map *map; | ||
39 | int i; | ||
40 | |||
41 | for (i = 0; i < FIX_N_IOREMAPS; i++) { | ||
42 | map = &ioremap_maps[i]; | ||
43 | map->fixmap_addr = __fix_to_virt(FIX_IOREMAP_BEGIN + i); | ||
44 | } | ||
45 | } | ||
46 | |||
47 | void __init __iomem * | ||
48 | ioremap_fixed(resource_size_t phys_addr, unsigned long offset, | ||
49 | unsigned long size, pgprot_t prot) | ||
50 | { | ||
51 | enum fixed_addresses idx0, idx; | ||
52 | struct ioremap_map *map; | ||
53 | unsigned int nrpages; | ||
54 | int i, slot; | ||
55 | |||
56 | slot = -1; | ||
57 | for (i = 0; i < FIX_N_IOREMAPS; i++) { | ||
58 | map = &ioremap_maps[i]; | ||
59 | if (!map->addr) { | ||
60 | map->size = size; | ||
61 | slot = i; | ||
62 | break; | ||
63 | } | ||
64 | } | ||
65 | |||
66 | if (slot < 0) | ||
67 | return NULL; | ||
68 | |||
69 | /* | ||
70 | * Mappings have to fit in the FIX_IOREMAP area. | ||
71 | */ | ||
72 | nrpages = size >> PAGE_SHIFT; | ||
73 | if (nrpages > FIX_N_IOREMAPS) | ||
74 | return NULL; | ||
75 | |||
76 | /* | ||
77 | * Ok, go for it.. | ||
78 | */ | ||
79 | idx0 = FIX_IOREMAP_BEGIN + slot; | ||
80 | idx = idx0; | ||
81 | while (nrpages > 0) { | ||
82 | pgprot_val(prot) |= _PAGE_WIRED; | ||
83 | __set_fixmap(idx, phys_addr, prot); | ||
84 | phys_addr += PAGE_SIZE; | ||
85 | idx++; | ||
86 | --nrpages; | ||
87 | } | ||
88 | |||
89 | map->addr = (void __iomem *)(offset + map->fixmap_addr); | ||
90 | return map->addr; | ||
91 | } | ||
92 | |||
93 | int iounmap_fixed(void __iomem *addr) | ||
94 | { | ||
95 | enum fixed_addresses idx; | ||
96 | struct ioremap_map *map; | ||
97 | unsigned int nrpages; | ||
98 | int i, slot; | ||
99 | |||
100 | slot = -1; | ||
101 | for (i = 0; i < FIX_N_IOREMAPS; i++) { | ||
102 | map = &ioremap_maps[i]; | ||
103 | if (map->addr == addr) { | ||
104 | slot = i; | ||
105 | break; | ||
106 | } | ||
107 | } | ||
108 | |||
109 | /* | ||
110 | * If we don't match, it's not for us. | ||
111 | */ | ||
112 | if (slot < 0) | ||
113 | return -EINVAL; | ||
114 | |||
115 | nrpages = map->size >> PAGE_SHIFT; | ||
116 | |||
117 | idx = FIX_IOREMAP_BEGIN + slot + nrpages - 1; | ||
118 | while (nrpages > 0) { | ||
119 | __clear_fixmap(idx, __pgprot(_PAGE_WIRED)); | ||
120 | --idx; | ||
121 | --nrpages; | ||
122 | } | ||
123 | |||
124 | map->size = 0; | ||
125 | map->addr = NULL; | ||
126 | |||
127 | return 0; | ||
128 | } | ||