What are the performance implications of using SPIM on the nRF52832 with anomaly-58-workaround?

Question

I am communicating with a sensor via SPIM. Without enabling `anomaly-58-workaround` I see numerous errors indicating 
 <wrn> spi_nrfx_spim: Transaction aborted since it would trigger nRF52832 PAN 58 
 All the read and write events happen with single buffers. From the description here it sounded like it applied to read/write calls with a single byte, but it seems to apply to calls with a single buffer, which is what I am using. 
 So I'm wondering: is there any benefit to using SPIM in this case, or does the single buffer case just fall back to using SPI without EasyDMA? I didn't notice any performance changes switching between the two, so I'm wondering if I'm actually just causing the MCU to work more rather than less by enabling SPIM. But I'm not sure exactly what the workaround does.

Einar Thorsrud · Accepted Answer

Hi, 
 The workaround does not work by using the SPI peripheral. Instead, it use GPIOTE via PPI to stop the SPI transaction by triggering the STOP task of the SPIM (you can see this in the implementation of anomaly_58_workaround_setup() if you are interested in the details). 
 If you have an available PPI and GPIOTE channel that is never used outside of this driver, the workaround shoudl be effective without significant side effects and this will be handled automatically as long as the workarond is enabled.

What are the performance implications of using SPIM on the nRF52832 with anomaly-58-workaround?

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