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-rw-r--r--arch/sh/mm/ioremap_fixed.c128
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
28struct ioremap_map {
29 void __iomem *addr;
30 unsigned long size;
31 unsigned long fixmap_addr;
32};
33
34static struct ioremap_map ioremap_maps[FIX_N_IOREMAPS];
35
36void __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
47void __init __iomem *
48ioremap_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
93int 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}