powerpc/PCI: Add legacy PCI access via sysfs

This patch adds support for legacy_io and legacy_mem files in
bus class directories in sysfs for powerpc

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
index ae2ea80..9047af7 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -74,6 +74,13 @@
 	unsigned long pci_io_size;
 #endif
 
+	/* Some machines have a special region to forward the ISA
+	 * "memory" cycles such as VGA memory regions. Left to 0
+	 * if unsupported
+	 */
+	resource_size_t	isa_mem_phys;
+	resource_size_t	isa_mem_size;
+
 	struct pci_ops *ops;
 	unsigned int __iomem *cfg_addr;
 	void __iomem *cfg_data;