Re: Question about ioremap and io_remap_page_range

[Jonathan Corbet]

> >      VIRT_ADDR = ioremap(BUS_ADDR); to map a section of PCI memory, and
> >      X_ADDR = virt_to_phys(VIRT_ADDR);
> 
> i'd suggest to read Documentation/DMA-mapping.txt in any recent kernel
> source, the bus_to_virt()/virt_to_phys() interface is obsolete and has
> been replaced by the pci_alloc_*/pci_map_*/pci_free_*() dynamic
> DMA-mapping API.

...or, of course, _Linux_Device_Drivers_, Second Edition, available online
at http://www.xml.com/ldd/chapter/book/index.html.  The DMA chapter covers
this API as well.

</self-promotion>

jon

Jonathan Corbet
Executive editor, LWN.net
[e-mail]