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 * */ 27 void __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 } 52 EXPORT_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 * */ 68 void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) 69 { 70 return pci_iomap_range(dev, bar, 0, maxlen); 71 } 72 EXPORT_SYMBOL(pci_iomap); 73 #endif /* CONFIG_PCI */ 74