CGEM_SPEC_ADDR_HI
WR4(sc, CGEM_SPEC_ADDR_HI(0), (eaddr[5] << 8) | eaddr[4]);
uint32_t high = RD4(sc, CGEM_SPEC_ADDR_HI(i)) & 0xffff;
WR4(sc, CGEM_SPEC_ADDR_HI(0), (eaddr[5] << 8) | eaddr[4]);
WR4(sc, CGEM_SPEC_ADDR_HI(i), 0);