In file included from include/linux/skbuff.h:34:0,
from include/linux/tcp.h:21,
from drivers/net/ethernet/amd/xgbe/xgbe-drv.c:119:
include/linux/dma-mapping.h: In function 'dma_map_resource':
>> include/linux/dma-mapping.h:274:22: error: implicit declaration of function '__phys_to_pfn' [-Werror=implicit-function-declaration]
unsigned long pfn = __phys_to_pfn(phys_addr);
^~~~~~~~~~~~~
ia64 does not provide __phys_to_pfn(), use the PHYS_PFN() alias.