49 lines
1.4 KiB
C
49 lines
1.4 KiB
C
/*
|
|
* Implement the default iomap interfaces
|
|
*
|
|
* (C) Copyright 2004 Linus Torvalds
|
|
*/
|
|
#include <linux/pci.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <linux/export.h>
|
|
|
|
#ifdef CONFIG_PCI
|
|
/**
|
|
* pci_iomap - create a virtual mapping cookie for a PCI BAR
|
|
* @dev: PCI device that owns the BAR
|
|
* @bar: BAR number
|
|
* @maxlen: length of the memory to map
|
|
*
|
|
* Using this function you will get a __iomem address to your device BAR.
|
|
* You can access it using ioread*() and iowrite*(). These functions hide
|
|
* the details if this is a MMIO or PIO address space and will just do what
|
|
* you expect from them in the correct way.
|
|
*
|
|
* @maxlen specifies the maximum length to map. If you want to get access to
|
|
* the complete BAR without checking for its length first, pass %0 here.
|
|
* */
|
|
void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
|
|
{
|
|
resource_size_t start = pci_resource_start(dev, bar);
|
|
resource_size_t len = pci_resource_len(dev, bar);
|
|
unsigned long flags = pci_resource_flags(dev, bar);
|
|
|
|
if (!len || !start)
|
|
return NULL;
|
|
if (maxlen && len > maxlen)
|
|
len = maxlen;
|
|
if (flags & IORESOURCE_IO)
|
|
return __pci_ioport_map(dev, start, len);
|
|
if (flags & IORESOURCE_MEM) {
|
|
if (flags & IORESOURCE_CACHEABLE)
|
|
return ioremap(start, len);
|
|
return ioremap_nocache(start, len);
|
|
}
|
|
/* What? */
|
|
return NULL;
|
|
}
|
|
|
|
EXPORT_SYMBOL(pci_iomap);
|
|
#endif /* CONFIG_PCI */
|