SPI_CSR_BITS_8
PUTREG(sc, SPI_CSR(0), SPI_CSR_SCBR | SPI_CSR_BITS_8);
PUTREG(sc, SPI_CSR(1), SPI_CSR_SCBR | SPI_CSR_BITS_8);
PUTREG(sc, SPI_CSR(2), SPI_CSR_SCBR | SPI_CSR_BITS_8);
PUTREG(sc, SPI_CSR(3), SPI_CSR_SCBR | SPI_CSR_BITS_8);
csr |= SPI_CSR_BITS_8; /* assume 8 bit transfers */