Hi, I would like to connect the LAN7430/7431 PCIe to Ethernet bridge on the PicoCore iMX8MP, but I'm missing the "CLKREQ#" pin, mandatory fro the LAN7430/7431.
How to add it?
Thanks!
mPCIe CLKREQ# pin
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The CLKREQ pin is availabe on J1.14 (UART_A_RTS) or J1.3 (I2C_B_SCL, 2.49k pull-up).
You have to configure your device tree accordingly.
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UART_A is for debug, however I don't need the RTS pin. Can I use both UART_A_TX/RX and the UART_A_RTS pin for CLKREQ concurrently?
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You need to switch UART_A_RTS signal to the CLKREQ function in the device tree. Then this pin is routed to the PCIe function in the processor.
This pin is then no longer used by the UART.
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Yes. UART_A can be used without RTS/CTS. The device tree is already prepared for this, just disable the CONFIG_PICOCOREMX8MP_UART_A_RTSCTS at the beginning.
However we don't have a setting for the CLKREQ signal, yet. So you have to add it manually. Add the following lines to the pciegrp node:
Your F&S Support Team
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Thanks, very appreciated!
