Is it possible to use nrf_spi_mngr with EASY DMA on nrf52832?

[Anthony Ambuehl]

I've been told due to PAN 58 it is not possible to use EASY DMA with nrf52832  without switching to the deprecated SPI driver.  Is there a workaround that allows the use of nrf_spi_mngr?    Without easy DMA the SPI bus speed is incredibly slow, operating 1/8th of the expected rate.

I'm using SDK 15.0.0 with nrf52832.

[hmolesworth]

Perhaps not an answer, but PAN 58 only applies to single byte SPI transfer and it seems that single byte transfer is an extremely inefficient use of SPI; I know I see examples here and there where users indeed do single byte transfers (mostly they are extracted from Arduino-style examples), but it would seem much more efficient to do multi-byte transfers where a packet is assembled then sent as a DMA burst. Any SPI transfer requiring a command-response in any case must have at least a 2-byte transfer, so there seems no sense in splitting that into single-byte transfers. Multiple byte transfers do not have any problems with DMA.

[Anthony Ambuehl]

Unfortunately our flash chip has some single byte commands as well as multibyte commands.  It doesn't seem unreasonable for the driver's to take care of the workarounds automatically.

[haakonsh]

If you want to use DMA then you'll need to use the legacy SPI peripheral for those 1 byte transfers. 

Do you mind sharing the flash chip's datasheet, maybe there's a way to use multi byte transfers regardless.