This patch configures Isolated Memory Regions (IMRs) to block DMA to
code and data regions that do not contain any data that needs to be
DMA-accessible.
This patch adds a simple, space-efficient driver for the Ethernet
interface built into the Intel Quark X1000. It only allocates a
single packet descriptor for each of the transmit and receive
directions, computes checksums on the CPU, and enables
store-and-forward mode for both transmit and receive directions.