| 1 | /* |
| 2 | * arch/parisc/mm/ioremap.c |
| 3 | * |
| 4 | * (C) Copyright 1995 1996 Linus Torvalds |
| 5 | * (C) Copyright 2001-2006 Helge Deller <deller@gmx.de> |
| 6 | * (C) Copyright 2005 Kyle McMartin <kyle@parisc-linux.org> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/vmalloc.h> |
| 10 | #include <linux/errno.h> |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/io.h> |
| 13 | #include <asm/pgalloc.h> |
| 14 | |
| 15 | /* |
| 16 | * Generic mapping function (not visible outside): |
| 17 | */ |
| 18 | |
| 19 | /* |
| 20 | * Remap an arbitrary physical address space into the kernel virtual |
| 21 | * address space. |
| 22 | * |
| 23 | * NOTE! We need to allow non-page-aligned mappings too: we will obviously |
| 24 | * have to convert them into an offset in a page-aligned mapping, but the |
| 25 | * caller shouldn't need to know that small detail. |
| 26 | */ |
| 27 | void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags) |
| 28 | { |
| 29 | void __iomem *addr; |
| 30 | struct vm_struct *area; |
| 31 | unsigned long offset, last_addr; |
| 32 | pgprot_t pgprot; |
| 33 | |
| 34 | #ifdef CONFIG_EISA |
| 35 | unsigned long end = phys_addr + size - 1; |
| 36 | /* Support EISA addresses */ |
| 37 | if ((phys_addr >= 0x00080000 && end < 0x000fffff) || |
| 38 | (phys_addr >= 0x00500000 && end < 0x03bfffff)) { |
| 39 | phys_addr |= F_EXTEND(0xfc000000); |
| 40 | flags |= _PAGE_NO_CACHE; |
| 41 | } |
| 42 | #endif |
| 43 | |
| 44 | /* Don't allow wraparound or zero size */ |
| 45 | last_addr = phys_addr + size - 1; |
| 46 | if (!size || last_addr < phys_addr) |
| 47 | return NULL; |
| 48 | |
| 49 | /* |
| 50 | * Don't allow anybody to remap normal RAM that we're using.. |
| 51 | */ |
| 52 | if (phys_addr < virt_to_phys(high_memory)) { |
| 53 | char *t_addr, *t_end; |
| 54 | struct page *page; |
| 55 | |
| 56 | t_addr = __va(phys_addr); |
| 57 | t_end = t_addr + (size - 1); |
| 58 | |
| 59 | for (page = virt_to_page(t_addr); |
| 60 | page <= virt_to_page(t_end); page++) { |
| 61 | if(!PageReserved(page)) |
| 62 | return NULL; |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | pgprot = __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | |
| 67 | _PAGE_ACCESSED | flags); |
| 68 | |
| 69 | /* |
| 70 | * Mappings have to be page-aligned |
| 71 | */ |
| 72 | offset = phys_addr & ~PAGE_MASK; |
| 73 | phys_addr &= PAGE_MASK; |
| 74 | size = PAGE_ALIGN(last_addr + 1) - phys_addr; |
| 75 | |
| 76 | /* |
| 77 | * Ok, go for it.. |
| 78 | */ |
| 79 | area = get_vm_area(size, VM_IOREMAP); |
| 80 | if (!area) |
| 81 | return NULL; |
| 82 | |
| 83 | addr = (void __iomem *) area->addr; |
| 84 | if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size, |
| 85 | phys_addr, pgprot)) { |
| 86 | vfree(addr); |
| 87 | return NULL; |
| 88 | } |
| 89 | |
| 90 | return (void __iomem *) (offset + (char __iomem *)addr); |
| 91 | } |
| 92 | EXPORT_SYMBOL(__ioremap); |
| 93 | |
| 94 | void iounmap(const volatile void __iomem *addr) |
| 95 | { |
| 96 | if (addr > high_memory) |
| 97 | return vfree((void *) (PAGE_MASK & (unsigned long __force) addr)); |
| 98 | } |
| 99 | EXPORT_SYMBOL(iounmap); |