In no MISO case, skip SPI read so that no more write/read delay contribute to SPI inter-frame delay when data is written successively.
Update targets:
- NUMAKER_PFM_NANO130
- NUMAKER_PFM_NUC472
- NUMAKER_PFM_M453
- NUMAKER_PFM_M487/NUMAKER_IOT_M487
- NU_PFM_M2351_*
- NUMAKER_IOT_M263A
- NUMAKER_M252KG
Without free-up of peripheral pins, peripheral pins of the same peripheral may
share by multiple ports after port iteration, and this peripheral may fail with
pin interference.
Better IP initialization sequence:
1. Configure IP pins
2. Select IP clock source and then enable it
3. Reset the IP (SYS_ResetModule)
NOTE1: IP reset takes effect regardless of IP clock. So it doesn't matter if
IP clock enable is before IP reset.
NOTE2: Non-configured pins may disturb IP's state, so IP pinout first and then
IP reset.
NOTE3: IP reset at the end of IP initialization sequence can cover unexpected
situation.
1. Disable unnecessary TX/RX threshold interrupts to avoid potential trap in DMA transfer
2. Start TX/RX DMA transfer simultaneously to fit H/W spec and avoid potential RX FIFO overflow issue
There is an easy default implementation of spi_master_block_write that
just calls spi_master_write in a loop, so the default implementation
of spi_master_block_write has been added to all targets.
Chun-Chieh Li
Russ Butler
Deepika
Christopher Haster