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		if (flags & IORESOURCE_CACHEABLE)
46			return ioremap(start, len);
47		return ioremap_nocache(start, len);
48	}
49	/* What? */
50	return NULL;
51}
52EXPORT_SYMBOL(pci_iomap_range);
53
54/**
55 * pci_iomap - create a virtual mapping cookie for a PCI BAR
56 * @dev: PCI device that owns the BAR
57 * @bar: BAR number
58 * @maxlen: length of the memory to map
59 *
60 * Using this function you will get a __iomem address to your device BAR.
61 * You can access it using ioread*() and iowrite*(). These functions hide
62 * the details if this is a MMIO or PIO address space and will just do what
63 * you expect from them in the correct way.
64 *
65 * @maxlen specifies the maximum length to map. If you want to get access to
66 * the complete BAR without checking for its length first, pass %0 here.
67 * */
68void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
69{
70	return pci_iomap_range(dev, bar, 0, maxlen);
71}
72EXPORT_SYMBOL(pci_iomap);
73#endif /* CONFIG_PCI */
74