topic Re: Spi communication m4 core to linux user space in i.MX Processors

Spi communication m4 core to linux user space

Dhevan — Mon, 31 May 2021 05:20:54 GMT

Hi,

We are using two spi interface for sensor communication parallel we are reading two spi interface we are facing issue for data loss.

Now we are planning to m4 code one spi and linux for one spi interface.

1) How to assign one spi for linux and another spi for m4 core in device tree and necessary change ?

2) How to transfer m4 spi data to linux user space code ?

Thanks & Regards,

Vasu

igorpadykov — Mon, 31 May 2021 23:12:29 GMT

Hi Vasu

1. one can look at ecspi examples (../driver_examples/ecspi) in SDK_EVK-MIMX8MM

2. one can look at rpmsg i2c example (i2c-rpmsg-imx.c) as reference

and description in sect.2.8 Remote Processor Messaging i.MX Linux Reference Manual

Best regards
igor

Dhevan — Tue, 01 Jun 2021 17:45:43 GMT

Thanks for your response.

I have refereed rpmsg_lite_str_echo_rtos example code this code working fine.

We want to read data from m4 core without send request.

Example code flow :

echo "test" > /dev/ttyRPMSG30 // Linux

Receive message and send back message to /dev/ttyRPMSG30 // M4 core

Our Requirement flow :

Send data continuously to /dev/ttyRPMSG30 // M4 Core

Linux user space we can read /dev/ttyRPMSG30 currently available data // Linux

Compulsory we has to send some dummy request then only we will get data ?

How to achieve our requirement ?

Thanks & Regards,

Vasu