pi@raspberrypi:~/ipxe/src $ make bin-arm32-efi/smsc95xx.efi
  [VERSION] bin-arm32-efi/version.smsc95xx.efi.o
  [LD] bin-arm32-efi/smsc95xx.efi.tmp
bin-arm32-efi/blib.a(uhci.o): In function `uhci_root_disable':
/home/pi/ipxe/src/drivers/usb/uhci.c:1203: undefined reference to `inw'
/home/pi/ipxe/src/drivers/usb/uhci.c:1205: undefined reference to `outw'
bin-arm32-efi/blib.a(uhci.o): In function `uhci_root_enable':
/home/pi/ipxe/src/drivers/usb/uhci.c:1161: undefined reference to `inw'
/home/pi/ipxe/src/drivers/usb/uhci.c:1163: undefined reference to `outw'
/home/pi/ipxe/src/drivers/usb/uhci.c:1166: undefined reference to `outw'
/home/pi/ipxe/src/drivers/usb/uhci.c:1171: undefined reference to `outw'
/home/pi/ipxe/src/drivers/usb/uhci.c:1178: undefined reference to `inw'
bin-arm32-efi/blib.a(uhci.o): In function `uhci_root_speed':
/home/pi/ipxe/src/drivers/usb/uhci.c:1224: undefined reference to `inw'
/home/pi/ipxe/src/drivers/usb/uhci.c:1249: undefined reference to `outw'
bin-arm32-efi/blib.a(uhci.o): In function `uhci_root_poll':
/home/pi/ipxe/src/drivers/usb/uhci.c:1285: undefined reference to `inw'
/home/pi/ipxe/src/drivers/usb/uhci.c:1292: undefined reference to `outw'
bin-arm32-efi/blib.a(uhci.o): In function `uhci_stop':
/home/pi/ipxe/src/drivers/usb/uhci.c:104: undefined reference to `inw'
/home/pi/ipxe/src/drivers/usb/uhci.c:106: undefined reference to `outw'
/home/pi/ipxe/src/drivers/usb/uhci.c:112: undefined reference to `inw'
bin-arm32-efi/blib.a(uhci.o): In function `uhci_reset':
/home/pi/ipxe/src/drivers/usb/uhci.c:144: undefined reference to `outw'
/home/pi/ipxe/src/drivers/usb/uhci.c:150: undefined reference to `inw'
bin-arm32-efi/blib.a(uhci.o): In function `uhci_bus_open':
/home/pi/ipxe/src/drivers/usb/uhci.c:1342: undefined reference to `outl'
bin-arm32-efi/blib.a(uhci.o): In function `uhci_run':
/home/pi/ipxe/src/drivers/usb/uhci.c:87: undefined reference to `inw'
/home/pi/ipxe/src/drivers/usb/uhci.c:89: undefined reference to `outw'
ld: bin-arm32-efi/smsc95xx.efi.tmp: hidden symbol `inw' isn't defined
ld: final link failed: Bad value
Makefile.housekeeping:1166: recipe for target 'bin-arm32-efi/smsc95xx.efi.tmp' failed
make: *** [bin-arm32-efi/smsc95xx.efi.tmp] Error 1
rm bin-arm32-efi/version.smsc95xx.efi.o