pci_iomap_wc (9) - Linux Manuals
pci_iomap_wc: create a virtual WC mapping cookie for a PCI BAR
pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR
void __iomem * pci_iomap_wc(struct pci_dev
* dev, int bar, unsigned long maxlen);
- PCI device that owns the BAR
- BAR number
- 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. When possible write combining is used.
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.
Matthew Wilcox <matthew [at] wil.cx>
Alan Cox <alan [at] lxorguk.ukuu.org.uk>