1/* 2 * (c) Copyright 2006, 2007 Hewlett-Packard Development Company, L.P. 3 * Bjorn Helgaas <bjorn.helgaas@hp.com> 4 * 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. 8 */ 9 10#include <linux/compiler.h> 11#include <linux/module.h> 12#include <linux/efi.h> 13#include <linux/io.h> 14#include <linux/vmalloc.h> 15#include <asm/io.h> 16#include <asm/meminit.h> 17 18static inline void __iomem * 19__ioremap (unsigned long phys_addr) 20{ 21 return (void __iomem *) (__IA64_UNCACHED_OFFSET | phys_addr); 22} 23 24void __iomem * 25early_ioremap (unsigned long phys_addr, unsigned long size) 26{ 27 return __ioremap(phys_addr); 28} 29 30void __iomem * 31ioremap (unsigned long phys_addr, unsigned long size) 32{ 33 void __iomem *addr; 34 struct vm_struct *area; 35 unsigned long offset; 36 pgprot_t prot; 37 u64 attr; 38 unsigned long gran_base, gran_size; 39 unsigned long page_base; 40 41 /* 42 * For things in kern_memmap, we must use the same attribute 43 * as the rest of the kernel. For more details, see 44 * Documentation/ia64/aliasing.txt. 45 */ 46 attr = kern_mem_attribute(phys_addr, size); 47 if (attr & EFI_MEMORY_WB) 48 return (void __iomem *) phys_to_virt(phys_addr); 49 else if (attr & EFI_MEMORY_UC) 50 return __ioremap(phys_addr); 51 52 /* 53 * Some chipsets don't support UC access to memory. If 54 * WB is supported for the whole granule, we prefer that. 55 */ 56 gran_base = GRANULEROUNDDOWN(phys_addr); 57 gran_size = GRANULEROUNDUP(phys_addr + size) - gran_base; 58 if (efi_mem_attribute(gran_base, gran_size) & EFI_MEMORY_WB) 59 return (void __iomem *) phys_to_virt(phys_addr); 60 61 /* 62 * WB is not supported for the whole granule, so we can't use 63 * the region 7 identity mapping. If we can safely cover the 64 * area with kernel page table mappings, we can use those 65 * instead. 66 */ 67 page_base = phys_addr & PAGE_MASK; 68 size = PAGE_ALIGN(phys_addr + size) - page_base; 69 if (efi_mem_attribute(page_base, size) & EFI_MEMORY_WB) { 70 prot = PAGE_KERNEL; 71 72 /* 73 * Mappings have to be page-aligned 74 */ 75 offset = phys_addr & ~PAGE_MASK; 76 phys_addr &= PAGE_MASK; 77 78 /* 79 * Ok, go for it.. 80 */ 81 area = get_vm_area(size, VM_IOREMAP); 82 if (!area) 83 return NULL; 84 85 area->phys_addr = phys_addr; 86 addr = (void __iomem *) area->addr; 87 if (ioremap_page_range((unsigned long) addr, 88 (unsigned long) addr + size, phys_addr, prot)) { 89 vunmap((void __force *) addr); 90 return NULL; 91 } 92 93 return (void __iomem *) (offset + (char __iomem *)addr); 94 } 95 96 return __ioremap(phys_addr); 97} 98EXPORT_SYMBOL(ioremap); 99 100void __iomem * 101ioremap_nocache (unsigned long phys_addr, unsigned long size) 102{ 103 if (kern_mem_attribute(phys_addr, size) & EFI_MEMORY_WB) 104 return NULL; 105 106 return __ioremap(phys_addr); 107} 108EXPORT_SYMBOL(ioremap_nocache); 109 110void 111early_iounmap (volatile void __iomem *addr, unsigned long size) 112{ 113} 114 115void 116iounmap (volatile void __iomem *addr) 117{ 118 if (REGION_NUMBER(addr) == RGN_GATE) 119 vunmap((void *) ((unsigned long) addr & PAGE_MASK)); 120} 121EXPORT_SYMBOL(iounmap); 122