[efi] Provide DMA operations for EFI PCI devices

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/include/ipxe/dma.h

@@ -32,6 +32,8 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 struct dma_mapping {
 	/** Device-side address */
 	physaddr_t addr;
+	/** Platform mapping token */
+	void *token;
 };
 
 /** A DMA-capable device */

src/include/ipxe/pci.h

@@ -12,6 +12,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #include <stdint.h>
 #include <ipxe/device.h>
 #include <ipxe/tables.h>
+#include <ipxe/dma.h>
 #include <ipxe/pci_io.h>
 
 /** PCI vendor ID */
@@ -187,6 +188,8 @@ struct pci_class_id {
 struct pci_device {
 	/** Generic device */
 	struct device dev;
+	/** DMA device */
+	struct dma_device dma;
 	/** Memory base
 	 *
 	 * This is the physical address of the first valid memory BAR.