AM625: SPI0 is not accesable in AM62x SK EVM

Hi Ravi,

Ravi Kumar Vodapalli said:

I am trying to access EXP_SPI0 interface in AM62x SK EVM, i wrote user space driver accessing /dev/spidev1.0. when sending data i am not able to see the data and clock signal when i connect to Oscilloscope.

In summary...

For the basic SPI device and associated pinmux setup that's needed just follow the DTS example that exposes SPI0 through the user expansion header on the SK-AM62 board that is already part of the SDK v9.x Kernel tree, please see here https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/tree/arch/arm64/boot/dts/ti/k3-am625-sk-mcspi-loopback.dtso?h=ti-linux-6.1.y

Then, instead of your own userspace driver you should first build and use the spidev_test tool that is part of the Linux kernel. It's a proven userspace tool you can use to send/receive data which will help validate your device tree and driver setup independent of your own userspace SW. The below FAQ discusses this tool and how to use it in the context of enabling DMA for SPI transfers (you don't need to do this particular part if performance is not super critical for you).

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1356551/faq-am6x-optimizing-spi-transfer-inter-byte-gaps-using-the-dma-in-linux

There's a lot of related content regarding this here on the E2E you should be able to search/find easily.

Regards, Andreas