LXR linux/lib/pci

   1/*
   2 * Implement the default iomap interfaces
   3 *
   4 * (C) Copyright 2004 Linus Torvalds
   5 */
   6#include <linux/pci.h>
   7#include <linux/io.h>
   8
   9#include <linux/export.h>
  10
  11#ifdef CONFIG_PCI
  12/**
  13 * pci_iomap_range - create a virtual mapping cookie for a PCI BAR
  14 * @dev: PCI device that owns the BAR
  15 * @bar: BAR number
  16 * @offset: map memory at the given offset in BAR
  17 * @maxlen: max length of the memory to map
  18 *
  19 * Using this function you will get a __iomem address to your device BAR.
  20 * You can access it using ioread*() and iowrite*(). These functions hide
  21 * the details if this is a MMIO or PIO address space and will just do what
  22 * you expect from them in the correct way.
  23 *
  24 * @maxlen specifies the maximum length to map. If you want to get access to
  25 * the complete BAR from offset to the end, pass %0 here.
  26 * */
  27void __iomem *pci_iomap_range(struct pci_dev *dev,
  28                              int bar,
  29                              unsigned long offset,
  30                              unsigned long maxlen)
  31{
  32        resource_size_t start = pci_resource_start(dev, bar);
  33        resource_size_t len = pci_resource_len(dev, bar);
  34        unsigned long flags = pci_resource_flags(dev, bar);
  35
  36        if (len <= offset || !start)
  37                return NULL;
  38        len -= offset;
  39        start += offset;
  40        if (maxlen && len > maxlen)
  41                len = maxlen;
  42        if (flags & IORESOURCE_IO)
  43                return __pci_ioport_map(dev, start, len);
  44        if (flags & IORESOURCE_MEM)
  45                return ioremap(start, len);
  46        /* What? */
  47        return NULL;
  48}
  49EXPORT_SYMBOL(pci_iomap_range);
  50
  51/**
  52 * pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR
  53 * @dev: PCI device that owns the BAR
  54 * @bar: BAR number
  55 * @offset: map memory at the given offset in BAR
  56 * @maxlen: max length of the memory to map
  57 *
  58 * Using this function you will get a __iomem address to your device BAR.
  59 * You can access it using ioread*() and iowrite*(). These functions hide
  60 * the details if this is a MMIO or PIO address space and will just do what
  61 * you expect from them in the correct way. When possible write combining
  62 * is used.
  63 *
  64 * @maxlen specifies the maximum length to map. If you want to get access to
  65 * the complete BAR from offset to the end, pass %0 here.
  66 * */
  67void __iomem *pci_iomap_wc_range(struct pci_dev *dev,
  68                                 int bar,
  69                                 unsigned long offset,
  70                                 unsigned long maxlen)
  71{
  72        resource_size_t start = pci_resource_start(dev, bar);
  73        resource_size_t len = pci_resource_len(dev, bar);
  74        unsigned long flags = pci_resource_flags(dev, bar);
  75
  76
  77        if (flags & IORESOURCE_IO)
  78                return NULL;
  79
  80        if (len <= offset || !start)
  81                return NULL;
  82
  83        len -= offset;
  84        start += offset;
  85        if (maxlen && len > maxlen)
  86                len = maxlen;
  87
  88        if (flags & IORESOURCE_MEM)
  89                return ioremap_wc(start, len);
  90
  91        /* What? */
  92        return NULL;
  93}
  94EXPORT_SYMBOL_GPL(pci_iomap_wc_range);
  95
  96/**
  97 * pci_iomap - create a virtual mapping cookie for a PCI BAR
  98 * @dev: PCI device that owns the BAR
  99 * @bar: BAR number
 100 * @maxlen: length of the memory to map
 101 *
 102 * Using this function you will get a __iomem address to your device BAR.
 103 * You can access it using ioread*() and iowrite*(). These functions hide
 104 * the details if this is a MMIO or PIO address space and will just do what
 105 * you expect from them in the correct way.
 106 *
 107 * @maxlen specifies the maximum length to map. If you want to get access to
 108 * the complete BAR without checking for its length first, pass %0 here.
 109 * */
 110void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
 111{
 112        return pci_iomap_range(dev, bar, 0, maxlen);
 113}
 114EXPORT_SYMBOL(pci_iomap);
 115
 116/**
 117 * pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR
 118 * @dev: PCI device that owns the BAR
 119 * @bar: BAR number
 120 * @maxlen: length of the memory to map
 121 *
 122 * Using this function you will get a __iomem address to your device BAR.
 123 * You can access it using ioread*() and iowrite*(). These functions hide
 124 * the details if this is a MMIO or PIO address space and will just do what
 125 * you expect from them in the correct way. When possible write combining
 126 * is used.
 127 *
 128 * @maxlen specifies the maximum length to map. If you want to get access to
 129 * the complete BAR without checking for its length first, pass %0 here.
 130 * */
 131void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen)
 132{
 133        return pci_iomap_wc_range(dev, bar, 0, maxlen);
 134}
 135EXPORT_SYMBOL_GPL(pci_iomap_wc);
 136#endif /* CONFIG_PCI */
 137