blob: 1725cd6db37a8f5e6a76f84192ef704838efb446 [file] [log] [blame]
Catalin Marinasfc478972012-03-05 11:49:29 +00001/*
2 * Based on arch/arm/mm/ioremap.c
3 *
4 * (C) Copyright 1995 1996 Linus Torvalds
5 * Hacked for ARM by Phil Blundell <philb@gnu.org>
6 * Hacked to allow all architectures to build, and various cleanups
7 * by Russell King
8 * Copyright (C) 2012 ARM Ltd.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 */
22
23#include <linux/export.h>
24#include <linux/mm.h>
25#include <linux/vmalloc.h>
26#include <linux/io.h>
27
28static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
29 pgprot_t prot, void *caller)
30{
31 unsigned long last_addr;
32 unsigned long offset = phys_addr & ~PAGE_MASK;
33 int err;
34 unsigned long addr;
35 struct vm_struct *area;
36
37 /*
38 * Page align the mapping address and size, taking account of any
39 * offset.
40 */
41 phys_addr &= PAGE_MASK;
42 size = PAGE_ALIGN(size + offset);
43
44 /*
45 * Don't allow wraparound, zero size or outside PHYS_MASK.
46 */
47 last_addr = phys_addr + size - 1;
48 if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK))
49 return NULL;
50
51 /*
52 * Don't allow RAM to be mapped.
53 */
54 if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))
55 return NULL;
56
57 area = get_vm_area_caller(size, VM_IOREMAP, caller);
58 if (!area)
59 return NULL;
60 addr = (unsigned long)area->addr;
61
62 err = ioremap_page_range(addr, addr + size, phys_addr, prot);
63 if (err) {
64 vunmap((void *)addr);
65 return NULL;
66 }
67
68 return (void __iomem *)(offset + addr);
69}
70
71void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
72{
73 return __ioremap_caller(phys_addr, size, prot,
74 __builtin_return_address(0));
75}
76EXPORT_SYMBOL(__ioremap);
77
78void __iounmap(volatile void __iomem *io_addr)
79{
80 void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
81
82 vunmap(addr);
83}
84EXPORT_SYMBOL(__iounmap);