include/linux/io.h

   1 /*
   2  * Copyright 2006 PathScale, Inc.  All Rights Reserved.
   3  *
   4  * This file is free software; you can redistribute it and/or modify
   5  * it under the terms of version 2 of the GNU General Public License
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software Foundation,
  15  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
  16  */
  17
  18 #ifndef _LINUX_IO_H
  19 #define _LINUX_IO_H
  20
  21 #include <linux/types.h>
  22 #include <linux/init.h>
  23 #include <linux/bug.h>
  24 #include <linux/err.h>
  25 #include <asm/io.h>
  26 #include <asm/page.h>
  27
  28 struct device;
  29 struct resource;
  30
  31 __visible void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
  32 void __ioread32_copy(void *to, const void __iomem *from, size_t count);
  33 void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
  34
  35 #ifdef CONFIG_MMU
  36 int ioremap_page_range(unsigned long addr, unsigned long end,
  37                        phys_addr_t phys_addr, pgprot_t prot);
  38 #else
  39 static inline int ioremap_page_range(unsigned long addr, unsigned long end,
  40                                      phys_addr_t phys_addr, pgprot_t prot)
  41 {
  42         return 0;
  43 }
  44 #endif
  45
  46 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
  47 void __init ioremap_huge_init(void);
  48 int arch_ioremap_pud_supported(void);
  49 int arch_ioremap_pmd_supported(void);
  50 #else
  51 static inline void ioremap_huge_init(void) { }
  52 #endif
  53
  54 /*
  55  * Managed iomap interface
  56  */
  57 #ifdef CONFIG_HAS_IOPORT_MAP
  58 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
  59                                unsigned int nr);
  60 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
  61 #else
  62 static inline void __iomem *devm_ioport_map(struct device *dev,
  63                                              unsigned long port,
  64                                              unsigned int nr)
  65 {
  66         return NULL;
  67 }
  68
  69 static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
  70 {
  71 }
  72 #endif
  73
  74 #define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err)
  75
  76 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
  77                            resource_size_t size);
  78 void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
  79                                    resource_size_t size);
  80 void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
  81                                    resource_size_t size);
  82 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
  83                                    resource_size_t size);
  84 void devm_iounmap(struct device *dev, void __iomem *addr);
  85 int check_signature(const volatile void __iomem *io_addr,
  86                         const unsigned char *signature, int length);
  87 void devm_ioremap_release(struct device *dev, void *res);
  88
  89 void *devm_memremap(struct device *dev, resource_size_t offset,
  90                 size_t size, unsigned long flags);
  91 void devm_memunmap(struct device *dev, void *addr);
  92
  93 void *__devm_memremap_pages(struct device *dev, struct resource *res);
  94
  95 #ifdef CONFIG_PCI
  96 /*
  97  * The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and
  98  * Posting") mandate non-posted configuration transactions. There is
  99  * no ioremap API in the kernel that can guarantee non-posted write
 100  * semantics across arches so provide a default implementation for
 101  * mapping PCI config space that defaults to ioremap_nocache(); arches
 102  * should override it if they have memory mapping implementations that
 103  * guarantee non-posted writes semantics to make the memory mapping
 104  * compliant with the PCI specification.
 105  */
 106 #ifndef pci_remap_cfgspace
 107 #define pci_remap_cfgspace pci_remap_cfgspace
 108 static inline void __iomem *pci_remap_cfgspace(phys_addr_t offset,
 109                                                size_t size)
 110 {
 111         return ioremap_nocache(offset, size);
 112 }
 113 #endif
 114 #endif
 115
 116 /*
 117  * Some systems do not have legacy ISA devices.
 118  * /dev/port is not a valid interface on these systems.
 119  * So for those archs, <asm/io.h> should define the following symbol.
 120  */
 121 #ifndef arch_has_dev_port
 122 #define arch_has_dev_port()     (1)
 123 #endif
 124
 125 /*
 126  * Some systems (x86 without PAT) have a somewhat reliable way to mark a
 127  * physical address range such that uncached mappings will actually
 128  * end up write-combining.  This facility should be used in conjunction
 129  * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
 130  * no effect if the per-page mechanisms are functional.
 131  * (On x86 without PAT, these functions manipulate MTRRs.)
 132  *
 133  * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
 134  * to have no effect.
 135  */
 136 #ifndef arch_phys_wc_add
 137 static inline int __must_check arch_phys_wc_add(unsigned long base,
 138                                                 unsigned long size)
 139 {
 140         return 0;  /* It worked (i.e. did nothing). */
 141 }
 142
 143 static inline void arch_phys_wc_del(int handle)
 144 {
 145 }
 146
 147 #define arch_phys_wc_add arch_phys_wc_add
 148 #ifndef arch_phys_wc_index
 149 static inline int arch_phys_wc_index(int handle)
 150 {
 151         return -1;
 152 }
 153 #define arch_phys_wc_index arch_phys_wc_index
 154 #endif
 155 #endif
 156
 157 enum {
 158         /* See memremap() kernel-doc for usage description... */
 159         MEMREMAP_WB = 1 << 0,
 160         MEMREMAP_WT = 1 << 1,
 161         MEMREMAP_WC = 1 << 2,
 162         MEMREMAP_ENC = 1 << 3,
 163         MEMREMAP_DEC = 1 << 4,
 164 };
 165
 166 void *memremap(resource_size_t offset, size_t size, unsigned long flags);
 167 void memunmap(void *addr);
 168
 169 /*
 170  * On x86 PAT systems we have memory tracking that keeps track of
 171  * the allowed mappings on memory ranges. This tracking works for
 172  * all the in-kernel mapping APIs (ioremap*), but where the user
 173  * wishes to map a range from a physical device into user memory
 174  * the tracking won't be updated. This API is to be used by
 175  * drivers which remap physical device pages into userspace,
 176  * and wants to make sure they are mapped WC and not UC.
 177  */
 178 #ifndef arch_io_reserve_memtype_wc
 179 static inline int arch_io_reserve_memtype_wc(resource_size_t base,
 180                                              resource_size_t size)
 181 {
 182         return 0;
 183 }
 184
 185 static inline void arch_io_free_memtype_wc(resource_size_t base,
 186                                            resource_size_t size)
 187 {
 188 }
 189 #endif
 190
 191 #endif /* _LINUX_IO_H */