| Catalin Marinas | fc47897 | 2012-03-05 11:49:29 +0000 | [diff] [blame] | 1 | /* |
| 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 | |
| 28 | static 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 | |
| 71 | void __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 | } |
| 76 | EXPORT_SYMBOL(__ioremap); |
| 77 | |
| 78 | void __iounmap(volatile void __iomem *io_addr) |
| 79 | { |
| 80 | void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr); |
| 81 | |
| 82 | vunmap(addr); |
| 83 | } |
| 84 | EXPORT_SYMBOL(__iounmap); |