NVRAM_FIRST
sum = rtcin(NVRAM_FIRST + CKSUM_MSB) << 8 |
rtcin(NVRAM_FIRST + CKSUM_LSB);
sum -= rtcin(NVRAM_FIRST + i);
nv_off = uio->uio_offset + NVRAM_FIRST;
if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST) {
sum += rtcin(NVRAM_FIRST + i);
writertc(NVRAM_FIRST + CKSUM_MSB, sum >> 8);
writertc(NVRAM_FIRST + CKSUM_LSB, sum);
nv_off = uio->uio_offset + NVRAM_FIRST;
if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)