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 __iowrite64_copy(void __iomem *to, const void *from, size_t count);
  33
  34 #ifdef CONFIG_MMU
  35 int ioremap_page_range(unsigned long addr, unsigned long end,
  36                        phys_addr_t phys_addr, pgprot_t prot);
  37 #else
  38 static inline int ioremap_page_range(unsigned long addr, unsigned long end,
  39                                      phys_addr_t phys_addr, pgprot_t prot)
  40 {
  41         return 0;
  42 }
  43 #endif
  44
  45 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
  46 void __init ioremap_huge_init(void);
  47 int arch_ioremap_pud_supported(void);
  48 int arch_ioremap_pmd_supported(void);
  49 #else
  50 static inline void ioremap_huge_init(void) { }
  51 #endif
  52
  53 /*
  54  * Managed iomap interface
  55  */
  56 #ifdef CONFIG_HAS_IOPORT_MAP
  57 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
  58                                unsigned int nr);
  59 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
  60 #else
  61 static inline void __iomem *devm_ioport_map(struct device *dev,
  62                                              unsigned long port,
  63                                              unsigned int nr)
  64 {
  65         return NULL;
  66 }
  67
  68 static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
  69 {
  70 }
  71 #endif
  72
  73 #define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err)
  74
  75 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
  76                            resource_size_t size);
  77 void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
  78                                    resource_size_t size);
  79 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
  80                                    resource_size_t size);
  81 void devm_iounmap(struct device *dev, void __iomem *addr);
  82 int check_signature(const volatile void __iomem *io_addr,
  83                         const unsigned char *signature, int length);
  84 void devm_ioremap_release(struct device *dev, void *res);
  85
  86 void *devm_memremap(struct device *dev, resource_size_t offset,
  87                 size_t size, unsigned long flags);
  88 void devm_memunmap(struct device *dev, void *addr);
  89
  90 void *__devm_memremap_pages(struct device *dev, struct resource *res);
  91
  92 #ifdef CONFIG_ZONE_DEVICE
  93 void *devm_memremap_pages(struct device *dev, struct resource *res);
  94 #else
  95 static inline void *devm_memremap_pages(struct device *dev, struct resource *res)
  96 {
  97         /*
  98          * Fail attempts to call devm_memremap_pages() without
  99          * ZONE_DEVICE support enabled, this requires callers to fall
 100          * back to plain devm_memremap() based on config
 101          */
 102         WARN_ON_ONCE(1);
 103         return ERR_PTR(-ENXIO);
 104 }
 105 #endif
 106
 107 /*
 108  * Some systems do not have legacy ISA devices.
 109  * /dev/port is not a valid interface on these systems.
 110  * So for those archs, <asm/io.h> should define the following symbol.
 111  */
 112 #ifndef arch_has_dev_port
 113 #define arch_has_dev_port()     (1)
 114 #endif
 115
 116 /*
 117  * Some systems (x86 without PAT) have a somewhat reliable way to mark a
 118  * physical address range such that uncached mappings will actually
 119  * end up write-combining.  This facility should be used in conjunction
 120  * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
 121  * no effect if the per-page mechanisms are functional.
 122  * (On x86 without PAT, these functions manipulate MTRRs.)
 123  *
 124  * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
 125  * to have no effect.
 126  */
 127 #ifndef arch_phys_wc_add
 128 static inline int __must_check arch_phys_wc_add(unsigned long base,
 129                                                 unsigned long size)
 130 {
 131         return 0;  /* It worked (i.e. did nothing). */
 132 }
 133
 134 static inline void arch_phys_wc_del(int handle)
 135 {
 136 }
 137
 138 #define arch_phys_wc_add arch_phys_wc_add
 139 #ifndef arch_phys_wc_index
 140 static inline int arch_phys_wc_index(int handle)
 141 {
 142         return -1;
 143 }
 144 #define arch_phys_wc_index arch_phys_wc_index
 145 #endif
 146 #endif
 147
 148 enum {
 149         /* See memremap() kernel-doc for usage description... */
 150         MEMREMAP_WB = 1 << 0,
 151         MEMREMAP_WT = 1 << 1,
 152 };
 153
 154 void *memremap(resource_size_t offset, size_t size, unsigned long flags);
 155 void memunmap(void *addr);
 156
 157 #endif /* _LINUX_IO_H */