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