On Sat, 25 Aug 2007 04:56:19 -0400
Jeff Garzik [off-list ref] wrote:

If the driver knows its MMIO, using readX/writeX after pci_iomap() is 
just fine, for all current implementations, and it makes sense that way.

There is nothing that guarantees this is permitted, any more than there
is anything saying not to use outb/outl. Some of the implementations do
quite strange things. It may happen to work but its not in the
documentation or the comments.

If you want to change this then you need to check the existing usages and
update all the docs if its safe, oh and tell the sparc64 pcmcia people to
take a hike, which is probably not a big problem.

Alan