| Michael S. Tsirkin | 66eab4d | 2011-11-24 20:45:20 +0200 | [diff] [blame] | 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 - create a virtual mapping cookie for a PCI BAR |
| 14 | * @dev: PCI device that owns the BAR |
| 15 | * @bar: BAR number |
| 16 | * @maxlen: length of the memory to map |
| 17 | * |
| 18 | * Using this function you will get a __iomem address to your device BAR. |
| 19 | * You can access it using ioread*() and iowrite*(). These functions hide |
| 20 | * the details if this is a MMIO or PIO address space and will just do what |
| 21 | * you expect from them in the correct way. |
| 22 | * |
| 23 | * @maxlen specifies the maximum length to map. If you want to get access to |
| 24 | * the complete BAR without checking for its length first, pass %0 here. |
| 25 | * */ |
| 26 | void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) |
| 27 | { |
| 28 | resource_size_t start = pci_resource_start(dev, bar); |
| 29 | resource_size_t len = pci_resource_len(dev, bar); |
| 30 | unsigned long flags = pci_resource_flags(dev, bar); |
| 31 | |
| 32 | if (!len || !start) |
| 33 | return NULL; |
| 34 | if (maxlen && len > maxlen) |
| 35 | len = maxlen; |
| 36 | if (flags & IORESOURCE_IO) |
| 37 | return ioport_map(start, len); |
| 38 | if (flags & IORESOURCE_MEM) { |
| 39 | if (flags & IORESOURCE_CACHEABLE) |
| 40 | return ioremap(start, len); |
| 41 | return ioremap_nocache(start, len); |
| 42 | } |
| 43 | /* What? */ |
| 44 | return NULL; |
| 45 | } |
| 46 | |
| 47 | EXPORT_SYMBOL(pci_iomap); |
| 48 | #endif /* CONFIG_PCI */ |