On Tue, Jul 01, 2014 at 07:43:34PM +0100, Liviu Dudau wrote:

Introduce a default implementation for remapping PCI bus I/O resources
onto the CPU address space. Architectures with special needs may
provide their own version, but most should be able to use this one.

[...]

+/**
+ *	pci_remap_iospace - Remap the memory mapped I/O space
+ *	@res: Resource describing the I/O space
+ *	@phys_addr: physical address where the range will be mapped.
+ *
+ *	Remap the memory mapped I/O space described by the @res
+ *	into the CPU physical address space. Only architectures
+ *	that have memory mapped IO defined (and hence PCI_IOBASE)
+ *	should call this function.
+ */
+int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
+{
+	int err = -ENODEV;
+
+#ifdef PCI_IOBASE
+	if (!(res->flags & IORESOURCE_IO))
+		return -EINVAL;
+
+	if (res->end > IO_SPACE_LIMIT)
+		return -EINVAL;
+
+	err = ioremap_page_range(res->start + (unsigned long)PCI_IOBASE,
+				res->end + 1 + (unsigned long)PCI_IOBASE,
+				phys_addr, __pgprot(PROT_DEVICE_nGnRE));

Except that PROT_DEVICE_nGnRE is arm64 only. I think that's a function
that should remain arch specific.

-- 
Catalin