The endianness of data exchange between tx and rx fifo is incorrect.
Earlier bytes are supposed to show up on MSB and later bytes on LSB,
ie: in big endian. The manual does not explicitly say this, but the
U-Boot and Linux driver codes have a swap on the data transferred
to tx fifo and from rx fifo.
With this change, U-Boot read from / write to SPI flash tests pass.
=> sf test 1ff000 1000
SPI flash test:
0 erase: 0 ticks, 4096000 KiB/s 32768.000 Mbps
1 check: 3 ticks, 1333 KiB/s 10.664 Mbps
2 write: 235 ticks, 17 KiB/s 0.136 Mbps
3 read: 2 ticks, 2000 KiB/s 16.000 Mbps
Test passed
0 erase: 0 ticks, 4096000 KiB/s 32768.000 Mbps
1 check: 3 ticks, 1333 KiB/s 10.664 Mbps
2 write: 235 ticks, 17 KiB/s 0.136 Mbps
3 read: 2 ticks, 2000 KiB/s 16.000 Mbps
Fixes: c906a3a01582 ("i.MX: Add the Freescale SPI Controller")
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210129132323.30946-11-bmeng.cn@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>