projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 5f97f7f9 HS |
1 | /* |
| 2 | * Copyright (C) 2004-2006 Atmel Corporation | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License version 2 as | |
| 6 | * published by the Free Software Foundation. | |
| 7 | */ | |
| 8 | #include <linux/vmalloc.h> | |
| 27ac792c | 9 | #include <linux/mm.h> |
| 5f97f7f9 | 10 | #include <linux/module.h> |
| 86c8eb36 | 11 | #include <linux/io.h> |
| 5a0e3ad6 | 12 | #include <linux/slab.h> |
| 5f97f7f9 | 13 | |
| 5f97f7f9 | 14 | #include <asm/pgtable.h> |
| 5f97f7f9 HS |
15 | #include <asm/addrspace.h> |
| 16 | ||
| 5f97f7f9 HS |
17 | /* |
| 18 | * Re-map an arbitrary physical address space into the kernel virtual | |
| 19 | * address space. Needed when the kernel wants to access physical | |
| 20 | * memory directly. | |
| 21 | */ | |
| 22 | void __iomem *__ioremap(unsigned long phys_addr, size_t size, | |
| 23 | unsigned long flags) | |
| 24 | { | |
| 86c8eb36 | 25 | unsigned long addr; |
| 5f97f7f9 HS |
26 | struct vm_struct *area; |
| 27 | unsigned long offset, last_addr; | |
| 28 | pgprot_t prot; | |
| 29 | ||
| 30 | /* | |
| 31 | * Check if we can simply use the P4 segment. This area is | |
| 32 | * uncacheable, so if caching/buffering is requested, we can't | |
| 33 | * use it. | |
| 34 | */ | |
| 35 | if ((phys_addr >= P4SEG) && (flags == 0)) | |
| 36 | return (void __iomem *)phys_addr; | |
| 37 | ||
| 38 | /* Don't allow wraparound or zero size */ | |
| 39 | last_addr = phys_addr + size - 1; | |
| 40 | if (!size || last_addr < phys_addr) | |
| 41 | return NULL; | |
| 42 | ||
| 43 | /* | |
| 44 | * XXX: When mapping regular RAM, we'd better make damn sure | |
| 45 | * it's never used for anything else. But this is really the | |
| 46 | * caller's responsibility... | |
| 47 | */ | |
| 48 | if (PHYSADDR(P2SEGADDR(phys_addr)) == phys_addr) | |
| 49 | return (void __iomem *)P2SEGADDR(phys_addr); | |
| 50 | ||
| 51 | /* Mappings have to be page-aligned */ | |
| 52 | offset = phys_addr & ~PAGE_MASK; | |
| 53 | phys_addr &= PAGE_MASK; | |
| 54 | size = PAGE_ALIGN(last_addr + 1) - phys_addr; | |
| 55 | ||
| 86c8eb36 | 56 | prot = __pgprot(_PAGE_PRESENT | _PAGE_GLOBAL | _PAGE_RW | _PAGE_DIRTY |
| 5f97f7f9 HS |
57 | | _PAGE_ACCESSED | _PAGE_TYPE_SMALL | flags); |
| 58 | ||
| 59 | /* | |
| 60 | * Ok, go for it.. | |
| 61 | */ | |
| 62 | area = get_vm_area(size, VM_IOREMAP); | |
| 63 | if (!area) | |
| 64 | return NULL; | |
| 65 | area->phys_addr = phys_addr; | |
| 86c8eb36 HS |
66 | addr = (unsigned long )area->addr; |
| 67 | if (ioremap_page_range(addr, addr + size, phys_addr, prot)) { | |
| 68 | vunmap((void *)addr); | |
| 5f97f7f9 HS |
69 | return NULL; |
| 70 | } | |
| 71 | ||
| 72 | return (void __iomem *)(offset + (char *)addr); | |
| 73 | } | |
| 74 | EXPORT_SYMBOL(__ioremap); | |
| 75 | ||
| 76 | void __iounmap(void __iomem *addr) | |
| 77 | { | |
| 78 | struct vm_struct *p; | |
| 79 | ||
| 80 | if ((unsigned long)addr >= P4SEG) | |
| 81 | return; | |
| bee8ce80 HS |
82 | if (PXSEG(addr) == P2SEG) |
| 83 | return; | |
| 5f97f7f9 HS |
84 | |
| 85 | p = remove_vm_area((void *)(PAGE_MASK & (unsigned long __force)addr)); | |
| 86 | if (unlikely(!p)) { | |
| 87 | printk (KERN_ERR "iounmap: bad address %p\n", addr); | |
| 88 | return; | |
| 89 | } | |
| 90 | ||
| 91 | kfree (p); | |
| 92 | } | |
| 93 | EXPORT_SYMBOL(__iounmap); |