| /* |
| * Copyright (C) 2004-2006 Atmel Corporation |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| #include <linux/vmalloc.h> |
| #include <linux/module.h> |
| #include <linux/io.h> |
| |
| #include <asm/pgtable.h> |
| #include <asm/addrspace.h> |
| |
| /* |
| * Re-map an arbitrary physical address space into the kernel virtual |
| * address space. Needed when the kernel wants to access physical |
| * memory directly. |
| */ |
| void __iomem *__ioremap(unsigned long phys_addr, size_t size, |
| unsigned long flags) |
| { |
| unsigned long addr; |
| struct vm_struct *area; |
| unsigned long offset, last_addr; |
| pgprot_t prot; |
| |
| /* |
| * Check if we can simply use the P4 segment. This area is |
| * uncacheable, so if caching/buffering is requested, we can't |
| * use it. |
| */ |
| if ((phys_addr >= P4SEG) && (flags == 0)) |
| return (void __iomem *)phys_addr; |
| |
| /* Don't allow wraparound or zero size */ |
| last_addr = phys_addr + size - 1; |
| if (!size || last_addr < phys_addr) |
| return NULL; |
| |
| /* |
| * XXX: When mapping regular RAM, we'd better make damn sure |
| * it's never used for anything else. But this is really the |
| * caller's responsibility... |
| */ |
| if (PHYSADDR(P2SEGADDR(phys_addr)) == phys_addr) |
| return (void __iomem *)P2SEGADDR(phys_addr); |
| |
| /* Mappings have to be page-aligned */ |
| offset = phys_addr & ~PAGE_MASK; |
| phys_addr &= PAGE_MASK; |
| size = PAGE_ALIGN(last_addr + 1) - phys_addr; |
| |
| prot = __pgprot(_PAGE_PRESENT | _PAGE_GLOBAL | _PAGE_RW | _PAGE_DIRTY |
| | _PAGE_ACCESSED | _PAGE_TYPE_SMALL | flags); |
| |
| /* |
| * Ok, go for it.. |
| */ |
| area = get_vm_area(size, VM_IOREMAP); |
| if (!area) |
| return NULL; |
| area->phys_addr = phys_addr; |
| addr = (unsigned long )area->addr; |
| if (ioremap_page_range(addr, addr + size, phys_addr, prot)) { |
| vunmap((void *)addr); |
| return NULL; |
| } |
| |
| return (void __iomem *)(offset + (char *)addr); |
| } |
| EXPORT_SYMBOL(__ioremap); |
| |
| void __iounmap(void __iomem *addr) |
| { |
| struct vm_struct *p; |
| |
| if ((unsigned long)addr >= P4SEG) |
| return; |
| |
| p = remove_vm_area((void *)(PAGE_MASK & (unsigned long __force)addr)); |
| if (unlikely(!p)) { |
| printk (KERN_ERR "iounmap: bad address %p\n", addr); |
| return; |
| } |
| |
| kfree (p); |
| } |
| EXPORT_SYMBOL(__iounmap); |