2 * (c) Copyright 2006, 2007 Hewlett-Packard Development Company, L.P.
3 * Bjorn Helgaas <bjorn.helgaas@hp.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/compiler.h>
11 #include <linux/module.h>
12 #include <linux/efi.h>
14 #include <linux/vmalloc.h>
16 #include <asm/meminit.h>
18 static inline void __iomem *
19 __ioremap_uc(unsigned long phys_addr)
21 return (void __iomem *) (__IA64_UNCACHED_OFFSET | phys_addr);
25 early_ioremap (unsigned long phys_addr, unsigned long size)
28 attr = kern_mem_attribute(phys_addr, size);
29 if (attr & EFI_MEMORY_WB)
30 return (void __iomem *) phys_to_virt(phys_addr);
31 return __ioremap_uc(phys_addr);
35 ioremap (unsigned long phys_addr, unsigned long size)
38 struct vm_struct *area;
42 unsigned long gran_base, gran_size;
43 unsigned long page_base;
46 * For things in kern_memmap, we must use the same attribute
47 * as the rest of the kernel. For more details, see
48 * Documentation/ia64/aliasing.txt.
50 attr = kern_mem_attribute(phys_addr, size);
51 if (attr & EFI_MEMORY_WB)
52 return (void __iomem *) phys_to_virt(phys_addr);
53 else if (attr & EFI_MEMORY_UC)
54 return __ioremap_uc(phys_addr);
57 * Some chipsets don't support UC access to memory. If
58 * WB is supported for the whole granule, we prefer that.
60 gran_base = GRANULEROUNDDOWN(phys_addr);
61 gran_size = GRANULEROUNDUP(phys_addr + size) - gran_base;
62 if (efi_mem_attribute(gran_base, gran_size) & EFI_MEMORY_WB)
63 return (void __iomem *) phys_to_virt(phys_addr);
66 * WB is not supported for the whole granule, so we can't use
67 * the region 7 identity mapping. If we can safely cover the
68 * area with kernel page table mappings, we can use those
71 page_base = phys_addr & PAGE_MASK;
72 size = PAGE_ALIGN(phys_addr + size) - page_base;
73 if (efi_mem_attribute(page_base, size) & EFI_MEMORY_WB) {
77 * Mappings have to be page-aligned
79 offset = phys_addr & ~PAGE_MASK;
80 phys_addr &= PAGE_MASK;
85 area = get_vm_area(size, VM_IOREMAP);
89 area->phys_addr = phys_addr;
90 addr = (void __iomem *) area->addr;
91 if (ioremap_page_range((unsigned long) addr,
92 (unsigned long) addr + size, phys_addr, prot)) {
93 vunmap((void __force *) addr);
97 return (void __iomem *) (offset + (char __iomem *)addr);
100 return __ioremap_uc(phys_addr);
102 EXPORT_SYMBOL(ioremap);
105 ioremap_nocache (unsigned long phys_addr, unsigned long size)
107 if (kern_mem_attribute(phys_addr, size) & EFI_MEMORY_WB)
110 return __ioremap_uc(phys_addr);
112 EXPORT_SYMBOL(ioremap_nocache);
115 early_iounmap (volatile void __iomem *addr, unsigned long size)
120 iounmap (volatile void __iomem *addr)
122 if (REGION_NUMBER(addr) == RGN_GATE)
123 vunmap((void *) ((unsigned long) addr & PAGE_MASK));
125 EXPORT_SYMBOL(iounmap);